xref: /btstack/src/hci.c (revision 761d36a9432d3bb2c22726a49686b6da46cfed76)
1 /*
2  * Copyright (C) 2014 BlueKitchen GmbH
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the copyright holders nor the names of
14  *    contributors may be used to endorse or promote products derived
15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
17  *    personal benefit and not for any commercial purpose or for
18  *    monetary gain.
19  *
20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
24  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 #define __BTSTACK_FILE__ "hci.c"
39 
40 /*
41  *  hci.c
42  *
43  *  Created by Matthias Ringwald on 4/29/09.
44  *
45  */
46 
47 #include "btstack_config.h"
48 
49 
50 #ifdef ENABLE_CLASSIC
51 #ifdef HAVE_EMBEDDED_TICK
52 #include "btstack_run_loop_embedded.h"
53 #endif
54 #endif
55 
56 #ifdef HAVE_PLATFORM_IPHONE_OS
57 #include "../port/ios/src/btstack_control_iphone.h"
58 #endif
59 
60 #ifdef ENABLE_BLE
61 #include "gap.h"
62 #endif
63 
64 #include <stdarg.h>
65 #include <string.h>
66 #include <stdio.h>
67 #include <inttypes.h>
68 
69 #include "btstack_debug.h"
70 #include "btstack_event.h"
71 #include "btstack_linked_list.h"
72 #include "btstack_memory.h"
73 #include "bluetooth_company_id.h"
74 #include "bluetooth_data_types.h"
75 #include "gap.h"
76 #include "hci.h"
77 #include "hci_cmd.h"
78 #include "hci_dump.h"
79 #include "ad_parser.h"
80 
81 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
82 #ifndef HCI_HOST_ACL_PACKET_NUM
83 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_NUM"
84 #endif
85 #ifndef HCI_HOST_ACL_PACKET_LEN
86 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_LEN"
87 #endif
88 #ifndef HCI_HOST_SCO_PACKET_NUM
89 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_NUM"
90 #endif
91 #ifndef HCI_HOST_SCO_PACKET_LEN
92 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_LEN"
93 #endif
94 #endif
95 
96 #define HCI_CONNECTION_TIMEOUT_MS 10000
97 #define HCI_RESET_RESEND_TIMEOUT_MS 200
98 
99 // Names are arbitrarily shortened to 32 bytes if not requested otherwise
100 #ifndef GAP_INQUIRY_MAX_NAME_LEN
101 #define GAP_INQUIRY_MAX_NAME_LEN 32
102 #endif
103 
104 // GAP inquiry state: 0 = off, 0x01 - 0x30 = requested duration, 0xfe = active, 0xff = stop requested
105 #define GAP_INQUIRY_DURATION_MIN 0x01
106 #define GAP_INQUIRY_DURATION_MAX 0x30
107 #define GAP_INQUIRY_STATE_ACTIVE 0x80
108 #define GAP_INQUIRY_STATE_IDLE 0
109 #define GAP_INQUIRY_STATE_W2_CANCEL 0x81
110 #define GAP_INQUIRY_STATE_W4_CANCELLED 0x82
111 
112 // GAP Remote Name Request
113 #define GAP_REMOTE_NAME_STATE_IDLE 0
114 #define GAP_REMOTE_NAME_STATE_W2_SEND 1
115 #define GAP_REMOTE_NAME_STATE_W4_COMPLETE 2
116 
117 // GAP Pairing
118 #define GAP_PAIRING_STATE_IDLE                       0
119 #define GAP_PAIRING_STATE_SEND_PIN                   1
120 #define GAP_PAIRING_STATE_SEND_PIN_NEGATIVE          2
121 #define GAP_PAIRING_STATE_SEND_PASSKEY               3
122 #define GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE      4
123 #define GAP_PAIRING_STATE_SEND_CONFIRMATION          5
124 #define GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE 6
125 
126 
127 // prototypes
128 #ifdef ENABLE_CLASSIC
129 static void hci_update_scan_enable(void);
130 static void hci_emit_discoverable_enabled(uint8_t enabled);
131 static int  hci_local_ssp_activated(void);
132 static int  hci_remote_ssp_supported(hci_con_handle_t con_handle);
133 static void hci_notify_if_sco_can_send_now(void);
134 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status);
135 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection);
136 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level);
137 static void hci_connection_timeout_handler(btstack_timer_source_t *timer);
138 static void hci_connection_timestamp(hci_connection_t *connection);
139 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn);
140 static void gap_inquiry_explode(uint8_t * packet);
141 #endif
142 
143 static int  hci_power_control_on(void);
144 static void hci_power_control_off(void);
145 static void hci_state_reset(void);
146 static void hci_emit_transport_packet_sent(void);
147 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason);
148 static void hci_emit_nr_connections_changed(void);
149 static void hci_emit_hci_open_failed(void);
150 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status);
151 static void hci_emit_event(uint8_t * event, uint16_t size, int dump);
152 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size);
153 static void hci_run(void);
154 static int  hci_is_le_connection(hci_connection_t * connection);
155 static int  hci_number_free_acl_slots_for_connection_type( bd_addr_type_t address_type);
156 static int hci_have_usb_transport(void);
157 
158 #ifdef ENABLE_BLE
159 #ifdef ENABLE_LE_CENTRAL
160 // called from test/ble_client/advertising_data_parser.c
161 void le_handle_advertisement_report(uint8_t *packet, uint16_t size);
162 static void hci_remove_from_whitelist(bd_addr_type_t address_type, bd_addr_t address);
163 static hci_connection_t * gap_get_outgoing_connection(void);
164 #endif
165 #endif
166 
167 // the STACK is here
168 #ifndef HAVE_MALLOC
169 static hci_stack_t   hci_stack_static;
170 #endif
171 static hci_stack_t * hci_stack = NULL;
172 
173 #ifdef ENABLE_CLASSIC
174 // default name
175 static const char * default_classic_name = "BTstack 00:00:00:00:00:00";
176 
177 // test helper
178 static uint8_t disable_l2cap_timeouts = 0;
179 #endif
180 
181 /**
182  * create connection for given address
183  *
184  * @return connection OR NULL, if no memory left
185  */
186 static hci_connection_t * create_connection_for_bd_addr_and_type(bd_addr_t addr, bd_addr_type_t addr_type){
187     log_info("create_connection_for_addr %s, type %x", bd_addr_to_str(addr), addr_type);
188     hci_connection_t * conn = btstack_memory_hci_connection_get();
189     if (!conn) return NULL;
190     bd_addr_copy(conn->address, addr);
191     conn->address_type = addr_type;
192     conn->con_handle = 0xffff;
193     conn->authentication_flags = AUTH_FLAGS_NONE;
194     conn->bonding_flags = 0;
195     conn->requested_security_level = LEVEL_0;
196 #ifdef ENABLE_CLASSIC
197     btstack_run_loop_set_timer_handler(&conn->timeout, hci_connection_timeout_handler);
198     btstack_run_loop_set_timer_context(&conn->timeout, conn);
199     hci_connection_timestamp(conn);
200 #endif
201     conn->acl_recombination_length = 0;
202     conn->acl_recombination_pos = 0;
203     conn->num_packets_sent = 0;
204 
205     conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
206 #ifdef ENABLE_BLE
207     conn->le_phy_update_all_phys = 0xff;
208 #endif
209     btstack_linked_list_add(&hci_stack->connections, (btstack_linked_item_t *) conn);
210     return conn;
211 }
212 
213 
214 /**
215  * get le connection parameter range
216 *
217  * @return le connection parameter range struct
218  */
219 void gap_get_connection_parameter_range(le_connection_parameter_range_t * range){
220     *range = hci_stack->le_connection_parameter_range;
221 }
222 
223 /**
224  * set le connection parameter range
225  *
226  */
227 
228 void gap_set_connection_parameter_range(le_connection_parameter_range_t *range){
229     hci_stack->le_connection_parameter_range = *range;
230 }
231 
232 /**
233  * @brief Test if connection parameters are inside in existing rage
234  * @param conn_interval_min (unit: 1.25ms)
235  * @param conn_interval_max (unit: 1.25ms)
236  * @param conn_latency
237  * @param supervision_timeout (unit: 10ms)
238  * @returns 1 if included
239  */
240 int gap_connection_parameter_range_included(le_connection_parameter_range_t * existing_range, uint16_t le_conn_interval_min, uint16_t le_conn_interval_max, uint16_t le_conn_latency, uint16_t le_supervision_timeout){
241     if (le_conn_interval_min < existing_range->le_conn_interval_min) return 0;
242     if (le_conn_interval_max > existing_range->le_conn_interval_max) return 0;
243 
244     if (le_conn_latency < existing_range->le_conn_latency_min) return 0;
245     if (le_conn_latency > existing_range->le_conn_latency_max) return 0;
246 
247     if (le_supervision_timeout < existing_range->le_supervision_timeout_min) return 0;
248     if (le_supervision_timeout > existing_range->le_supervision_timeout_max) return 0;
249 
250     return 1;
251 }
252 
253 /**
254  * @brief Set max number of connections in LE Peripheral role (if Bluetooth Controller supports it)
255  * @note: default: 1
256  * @param max_peripheral_connections
257  */
258 #ifdef ENABLE_LE_PERIPHERAL
259 void gap_set_max_number_peripheral_connections(int max_peripheral_connections){
260     hci_stack->le_max_number_peripheral_connections = max_peripheral_connections;
261 }
262 #endif
263 
264 /**
265  * get hci connections iterator
266  *
267  * @return hci connections iterator
268  */
269 
270 void hci_connections_get_iterator(btstack_linked_list_iterator_t *it){
271     btstack_linked_list_iterator_init(it, &hci_stack->connections);
272 }
273 
274 /**
275  * get connection for a given handle
276  *
277  * @return connection OR NULL, if not found
278  */
279 hci_connection_t * hci_connection_for_handle(hci_con_handle_t con_handle){
280     btstack_linked_list_iterator_t it;
281     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
282     while (btstack_linked_list_iterator_has_next(&it)){
283         hci_connection_t * item = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
284         if ( item->con_handle == con_handle ) {
285             return item;
286         }
287     }
288     return NULL;
289 }
290 
291 /**
292  * get connection for given address
293  *
294  * @return connection OR NULL, if not found
295  */
296 hci_connection_t * hci_connection_for_bd_addr_and_type(bd_addr_t  addr, bd_addr_type_t addr_type){
297     btstack_linked_list_iterator_t it;
298     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
299     while (btstack_linked_list_iterator_has_next(&it)){
300         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
301         if (connection->address_type != addr_type)  continue;
302         if (memcmp(addr, connection->address, 6) != 0) continue;
303         return connection;
304     }
305     return NULL;
306 }
307 
308 
309 #ifdef ENABLE_CLASSIC
310 
311 #ifdef ENABLE_SCO_OVER_HCI
312 static int hci_number_sco_connections(void){
313     int connections = 0;
314     btstack_linked_list_iterator_t it;
315     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
316     while (btstack_linked_list_iterator_has_next(&it)){
317         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
318         if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
319         connections++;
320     }
321     return connections;
322 }
323 #endif
324 
325 static void hci_connection_timeout_handler(btstack_timer_source_t *timer){
326     hci_connection_t * connection = (hci_connection_t *) btstack_run_loop_get_timer_context(timer);
327 #ifdef HAVE_EMBEDDED_TICK
328     if (btstack_run_loop_embedded_get_ticks() > connection->timestamp + btstack_run_loop_embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
329         // connections might be timed out
330         hci_emit_l2cap_check_timeout(connection);
331     }
332 #else
333     if (btstack_run_loop_get_time_ms() > connection->timestamp + HCI_CONNECTION_TIMEOUT_MS){
334         // connections might be timed out
335         hci_emit_l2cap_check_timeout(connection);
336     }
337 #endif
338 }
339 
340 static void hci_connection_timestamp(hci_connection_t *connection){
341 #ifdef HAVE_EMBEDDED_TICK
342     connection->timestamp = btstack_run_loop_embedded_get_ticks();
343 #else
344     connection->timestamp = btstack_run_loop_get_time_ms();
345 #endif
346 }
347 
348 inline static void connectionSetAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
349     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags | flags);
350 }
351 
352 
353 inline static void connectionClearAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
354     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags & ~flags);
355 }
356 
357 /**
358  * add authentication flags and reset timer
359  * @note: assumes classic connection
360  * @note: bd_addr is passed in as litle endian uint8_t * as it is called from parsing packets
361  */
362 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
363     bd_addr_t addr;
364     reverse_bd_addr(bd_addr, addr);
365     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
366     if (conn) {
367         connectionSetAuthenticationFlags(conn, flags);
368         hci_connection_timestamp(conn);
369     }
370 }
371 
372 int  hci_authentication_active_for_handle(hci_con_handle_t handle){
373     hci_connection_t * conn = hci_connection_for_handle(handle);
374     if (!conn) return 0;
375     if (conn->authentication_flags & LEGACY_PAIRING_ACTIVE) return 1;
376     if (conn->authentication_flags & SSP_PAIRING_ACTIVE) return 1;
377     return 0;
378 }
379 
380 void gap_drop_link_key_for_bd_addr(bd_addr_t addr){
381     if (!hci_stack->link_key_db) return;
382     log_info("gap_drop_link_key_for_bd_addr: %s", bd_addr_to_str(addr));
383     hci_stack->link_key_db->delete_link_key(addr);
384 }
385 
386 void gap_store_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t type){
387     if (!hci_stack->link_key_db) return;
388     log_info("gap_store_link_key_for_bd_addr: %s, type %u", bd_addr_to_str(addr), type);
389     hci_stack->link_key_db->put_link_key(addr, link_key, type);
390 }
391 
392 void gap_delete_all_link_keys(void){
393     bd_addr_t  addr;
394     link_key_t link_key;
395     link_key_type_t type;
396     btstack_link_key_iterator_t it;
397     int ok = gap_link_key_iterator_init(&it);
398     if (!ok) {
399         log_error("could not initialize iterator");
400         return;
401     }
402     while (gap_link_key_iterator_get_next(&it, addr, link_key, &type)){
403         gap_drop_link_key_for_bd_addr(addr);
404     }
405     gap_link_key_iterator_done(&it);
406 }
407 
408 int gap_link_key_iterator_init(btstack_link_key_iterator_t * it){
409     if (!hci_stack->link_key_db) return 0;
410     if (!hci_stack->link_key_db->iterator_init) return 0;
411     return hci_stack->link_key_db->iterator_init(it);
412 }
413 int gap_link_key_iterator_get_next(btstack_link_key_iterator_t * it, bd_addr_t bd_addr, link_key_t link_key, link_key_type_t * type){
414     if (!hci_stack->link_key_db) return 0;
415     return hci_stack->link_key_db->iterator_get_next(it, bd_addr, link_key, type);
416 }
417 void gap_link_key_iterator_done(btstack_link_key_iterator_t * it){
418     if (!hci_stack->link_key_db) return;
419     hci_stack->link_key_db->iterator_done(it);
420 }
421 #endif
422 
423 static int hci_is_le_connection(hci_connection_t * connection){
424     switch (connection->address_type){
425         case BD_ADDR_TYPE_LE_PUBLIC:
426         case BD_ADDR_TYPE_LE_RANDOM:
427         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_PUBLIC:
428         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_RANDOM:
429             return 1;
430         default:
431             return 0;
432     }
433 }
434 
435 /**
436  * count connections
437  */
438 static int nr_hci_connections(void){
439     int count = 0;
440     btstack_linked_item_t *it;
441     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next, count++);
442     return count;
443 }
444 
445 static int hci_number_free_acl_slots_for_connection_type(bd_addr_type_t address_type){
446 
447     unsigned int num_packets_sent_classic = 0;
448     unsigned int num_packets_sent_le = 0;
449 
450     btstack_linked_item_t *it;
451     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
452         hci_connection_t * connection = (hci_connection_t *) it;
453         if (hci_is_le_connection(connection)){
454             num_packets_sent_le += connection->num_packets_sent;
455         }
456         if (connection->address_type == BD_ADDR_TYPE_CLASSIC){
457             num_packets_sent_classic += connection->num_packets_sent;
458         }
459     }
460     log_debug("ACL classic buffers: %u used of %u", num_packets_sent_classic, hci_stack->acl_packets_total_num);
461     int free_slots_classic = hci_stack->acl_packets_total_num - num_packets_sent_classic;
462     int free_slots_le = 0;
463 
464     if (free_slots_classic < 0){
465         log_error("hci_number_free_acl_slots: outgoing classic packets (%u) > total classic packets (%u)", num_packets_sent_classic, hci_stack->acl_packets_total_num);
466         return 0;
467     }
468 
469     if (hci_stack->le_acl_packets_total_num){
470         // if we have LE slots, they are used
471         free_slots_le = hci_stack->le_acl_packets_total_num - num_packets_sent_le;
472         if (free_slots_le < 0){
473             log_error("hci_number_free_acl_slots: outgoing le packets (%u) > total le packets (%u)", num_packets_sent_le, hci_stack->le_acl_packets_total_num);
474             return 0;
475         }
476     } else {
477         // otherwise, classic slots are used for LE, too
478         free_slots_classic -= num_packets_sent_le;
479         if (free_slots_classic < 0){
480             log_error("hci_number_free_acl_slots: outgoing classic + le packets (%u + %u) > total packets (%u)", num_packets_sent_classic, num_packets_sent_le, hci_stack->acl_packets_total_num);
481             return 0;
482         }
483     }
484 
485     switch (address_type){
486         case BD_ADDR_TYPE_UNKNOWN:
487             log_error("hci_number_free_acl_slots: unknown address type");
488             return 0;
489 
490         case BD_ADDR_TYPE_CLASSIC:
491             return free_slots_classic;
492 
493         default:
494            if (hci_stack->le_acl_packets_total_num){
495                return free_slots_le;
496            }
497            return free_slots_classic;
498     }
499 }
500 
501 int hci_number_free_acl_slots_for_handle(hci_con_handle_t con_handle){
502     // get connection type
503     hci_connection_t * connection = hci_connection_for_handle(con_handle);
504     if (!connection){
505         log_error("hci_number_free_acl_slots: handle 0x%04x not in connection list", con_handle);
506         return 0;
507     }
508     return hci_number_free_acl_slots_for_connection_type(connection->address_type);
509 }
510 
511 #ifdef ENABLE_CLASSIC
512 static int hci_number_free_sco_slots(void){
513     unsigned int num_sco_packets_sent  = 0;
514     btstack_linked_item_t *it;
515     if (hci_stack->synchronous_flow_control_enabled){
516         // explicit flow control
517         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
518             hci_connection_t * connection = (hci_connection_t *) it;
519             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
520             num_sco_packets_sent += connection->num_packets_sent;
521         }
522         if (num_sco_packets_sent > hci_stack->sco_packets_total_num){
523             log_info("hci_number_free_sco_slots:packets (%u) > total packets (%u)", num_sco_packets_sent, hci_stack->sco_packets_total_num);
524             return 0;
525         }
526         return hci_stack->sco_packets_total_num - num_sco_packets_sent;
527     } else {
528         // implicit flow control -- TODO
529         int num_ready = 0;
530         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
531             hci_connection_t * connection = (hci_connection_t *) it;
532             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
533             if (connection->sco_tx_ready == 0) continue;
534             num_ready++;
535         }
536         return num_ready;
537     }
538 }
539 #endif
540 
541 // only used to send HCI Host Number Completed Packets
542 static int hci_can_send_comand_packet_transport(void){
543     if (hci_stack->hci_packet_buffer_reserved) return 0;
544 
545     // check for async hci transport implementations
546     if (hci_stack->hci_transport->can_send_packet_now){
547         if (!hci_stack->hci_transport->can_send_packet_now(HCI_COMMAND_DATA_PACKET)){
548             return 0;
549         }
550     }
551     return 1;
552 }
553 
554 // new functions replacing hci_can_send_packet_now[_using_packet_buffer]
555 int hci_can_send_command_packet_now(void){
556     if (hci_can_send_comand_packet_transport() == 0) return 0;
557     return hci_stack->num_cmd_packets > 0;
558 }
559 
560 static int hci_transport_can_send_prepared_packet_now(uint8_t packet_type){
561     // check for async hci transport implementations
562     if (!hci_stack->hci_transport->can_send_packet_now) return 1;
563     return hci_stack->hci_transport->can_send_packet_now(packet_type);
564 }
565 
566 static int hci_can_send_prepared_acl_packet_for_address_type(bd_addr_type_t address_type){
567     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
568     return hci_number_free_acl_slots_for_connection_type(address_type) > 0;
569 }
570 
571 int hci_can_send_acl_le_packet_now(void){
572     if (hci_stack->hci_packet_buffer_reserved) return 0;
573     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_LE_PUBLIC);
574 }
575 
576 int hci_can_send_prepared_acl_packet_now(hci_con_handle_t con_handle) {
577     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
578     return hci_number_free_acl_slots_for_handle(con_handle) > 0;
579 }
580 
581 int hci_can_send_acl_packet_now(hci_con_handle_t con_handle){
582     if (hci_stack->hci_packet_buffer_reserved) return 0;
583     return hci_can_send_prepared_acl_packet_now(con_handle);
584 }
585 
586 #ifdef ENABLE_CLASSIC
587 int hci_can_send_acl_classic_packet_now(void){
588     if (hci_stack->hci_packet_buffer_reserved) return 0;
589     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_CLASSIC);
590 }
591 
592 int hci_can_send_prepared_sco_packet_now(void){
593     if (!hci_transport_can_send_prepared_packet_now(HCI_SCO_DATA_PACKET)) return 0;
594     if (hci_have_usb_transport()){
595         return hci_stack->sco_can_send_now;
596     } else {
597         return hci_number_free_sco_slots() > 0;
598     }
599 }
600 
601 int hci_can_send_sco_packet_now(void){
602     if (hci_stack->hci_packet_buffer_reserved) return 0;
603     return hci_can_send_prepared_sco_packet_now();
604 }
605 
606 void hci_request_sco_can_send_now_event(void){
607     hci_stack->sco_waiting_for_can_send_now = 1;
608     hci_notify_if_sco_can_send_now();
609 }
610 #endif
611 
612 // used for internal checks in l2cap.c
613 int hci_is_packet_buffer_reserved(void){
614     return hci_stack->hci_packet_buffer_reserved;
615 }
616 
617 // reserves outgoing packet buffer. @returns 1 if successful
618 int hci_reserve_packet_buffer(void){
619     if (hci_stack->hci_packet_buffer_reserved) {
620         log_error("hci_reserve_packet_buffer called but buffer already reserved");
621         return 0;
622     }
623     hci_stack->hci_packet_buffer_reserved = 1;
624     return 1;
625 }
626 
627 void hci_release_packet_buffer(void){
628     hci_stack->hci_packet_buffer_reserved = 0;
629 }
630 
631 // assumption: synchronous implementations don't provide can_send_packet_now as they don't keep the buffer after the call
632 static int hci_transport_synchronous(void){
633     return hci_stack->hci_transport->can_send_packet_now == NULL;
634 }
635 
636 static int hci_send_acl_packet_fragments(hci_connection_t *connection){
637 
638     // log_info("hci_send_acl_packet_fragments  %u/%u (con 0x%04x)", hci_stack->acl_fragmentation_pos, hci_stack->acl_fragmentation_total_size, connection->con_handle);
639 
640     // max ACL data packet length depends on connection type (LE vs. Classic) and available buffers
641     uint16_t max_acl_data_packet_length = hci_stack->acl_data_packet_length;
642     if (hci_is_le_connection(connection) && hci_stack->le_data_packets_length > 0){
643         max_acl_data_packet_length = hci_stack->le_data_packets_length;
644     }
645 
646     // testing: reduce buffer to minimum
647     // max_acl_data_packet_length = 52;
648 
649     log_debug("hci_send_acl_packet_fragments entered");
650 
651     int err;
652     // multiple packets could be send on a synchronous HCI transport
653     while (1){
654 
655         log_debug("hci_send_acl_packet_fragments loop entered");
656 
657         // get current data
658         const uint16_t acl_header_pos = hci_stack->acl_fragmentation_pos - 4;
659         int current_acl_data_packet_length = hci_stack->acl_fragmentation_total_size - hci_stack->acl_fragmentation_pos;
660         int more_fragments = 0;
661 
662         // if ACL packet is larger than Bluetooth packet buffer, only send max_acl_data_packet_length
663         if (current_acl_data_packet_length > max_acl_data_packet_length){
664             more_fragments = 1;
665             current_acl_data_packet_length = max_acl_data_packet_length;
666         }
667 
668         // copy handle_and_flags if not first fragment and update packet boundary flags to be 01 (continuing fragmnent)
669         if (acl_header_pos > 0){
670             uint16_t handle_and_flags = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
671             handle_and_flags = (handle_and_flags & 0xcfff) | (1 << 12);
672             little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos, handle_and_flags);
673         }
674 
675         // update header len
676         little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos + 2, current_acl_data_packet_length);
677 
678         // count packet
679         connection->num_packets_sent++;
680         log_debug("hci_send_acl_packet_fragments loop before send (more fragments %d)", more_fragments);
681 
682         // update state for next fragment (if any) as "transport done" might be sent during send_packet already
683         if (more_fragments){
684             // update start of next fragment to send
685             hci_stack->acl_fragmentation_pos += current_acl_data_packet_length;
686         } else {
687             // done
688             hci_stack->acl_fragmentation_pos = 0;
689             hci_stack->acl_fragmentation_total_size = 0;
690         }
691 
692         // send packet
693         uint8_t * packet = &hci_stack->hci_packet_buffer[acl_header_pos];
694         const int size = current_acl_data_packet_length + 4;
695         hci_dump_packet(HCI_ACL_DATA_PACKET, 0, packet, size);
696         hci_stack->acl_fragmentation_tx_active = 1;
697         err = hci_stack->hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
698 
699         log_debug("hci_send_acl_packet_fragments loop after send (more fragments %d)", more_fragments);
700 
701         // done yet?
702         if (!more_fragments) break;
703 
704         // can send more?
705         if (!hci_can_send_prepared_acl_packet_now(connection->con_handle)) return err;
706     }
707 
708     log_debug("hci_send_acl_packet_fragments loop over");
709 
710     // release buffer now for synchronous transport
711     if (hci_transport_synchronous()){
712         hci_stack->acl_fragmentation_tx_active = 0;
713         hci_release_packet_buffer();
714         hci_emit_transport_packet_sent();
715     }
716 
717     return err;
718 }
719 
720 // pre: caller has reserved the packet buffer
721 int hci_send_acl_packet_buffer(int size){
722 
723     // log_info("hci_send_acl_packet_buffer size %u", size);
724 
725     if (!hci_stack->hci_packet_buffer_reserved) {
726         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
727         return 0;
728     }
729 
730     uint8_t * packet = hci_stack->hci_packet_buffer;
731     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
732 
733     // check for free places on Bluetooth module
734     if (!hci_can_send_prepared_acl_packet_now(con_handle)) {
735         log_error("hci_send_acl_packet_buffer called but no free ACL buffers on controller");
736         hci_release_packet_buffer();
737         hci_emit_transport_packet_sent();
738         return BTSTACK_ACL_BUFFERS_FULL;
739     }
740 
741     hci_connection_t *connection = hci_connection_for_handle( con_handle);
742     if (!connection) {
743         log_error("hci_send_acl_packet_buffer called but no connection for handle 0x%04x", con_handle);
744         hci_release_packet_buffer();
745         hci_emit_transport_packet_sent();
746         return 0;
747     }
748 
749 #ifdef ENABLE_CLASSIC
750     hci_connection_timestamp(connection);
751 #endif
752 
753     // hci_dump_packet( HCI_ACL_DATA_PACKET, 0, packet, size);
754 
755     // setup data
756     hci_stack->acl_fragmentation_total_size = size;
757     hci_stack->acl_fragmentation_pos = 4;   // start of L2CAP packet
758 
759     return hci_send_acl_packet_fragments(connection);
760 }
761 
762 #ifdef ENABLE_CLASSIC
763 // pre: caller has reserved the packet buffer
764 int hci_send_sco_packet_buffer(int size){
765 
766     // log_info("hci_send_acl_packet_buffer size %u", size);
767 
768     if (!hci_stack->hci_packet_buffer_reserved) {
769         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
770         return 0;
771     }
772 
773     uint8_t * packet = hci_stack->hci_packet_buffer;
774 
775     // skip checks in loopback mode
776     if (!hci_stack->loopback_mode){
777         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);   // same for ACL and SCO
778 
779         // check for free places on Bluetooth module
780         if (!hci_can_send_prepared_sco_packet_now()) {
781             log_error("hci_send_sco_packet_buffer called but no free SCO buffers on controller");
782             hci_release_packet_buffer();
783             hci_emit_transport_packet_sent();
784             return BTSTACK_ACL_BUFFERS_FULL;
785         }
786 
787         // track send packet in connection struct
788         hci_connection_t *connection = hci_connection_for_handle( con_handle);
789         if (!connection) {
790             log_error("hci_send_sco_packet_buffer called but no connection for handle 0x%04x", con_handle);
791             hci_release_packet_buffer();
792             hci_emit_transport_packet_sent();
793             return 0;
794         }
795 
796         if (hci_have_usb_transport()){
797             // token used
798             hci_stack->sco_can_send_now = 0;
799         } else {
800             if (hci_stack->synchronous_flow_control_enabled){
801                 connection->num_packets_sent++;
802             } else {
803                 connection->sco_tx_ready--;
804             }
805         }
806     }
807 
808     hci_dump_packet( HCI_SCO_DATA_PACKET, 0, packet, size);
809     int err = hci_stack->hci_transport->send_packet(HCI_SCO_DATA_PACKET, packet, size);
810 
811     if (hci_transport_synchronous()){
812         hci_release_packet_buffer();
813         hci_emit_transport_packet_sent();
814     }
815 
816     return err;
817 }
818 #endif
819 
820 static void acl_handler(uint8_t *packet, int size){
821 
822     // log_info("acl_handler: size %u", size);
823 
824     // get info
825     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
826     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
827     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
828     uint16_t acl_length         = READ_ACL_LENGTH(packet);
829 
830     // ignore non-registered handle
831     if (!conn){
832         log_error( "hci.c: acl_handler called with non-registered handle %u!" , con_handle);
833         return;
834     }
835 
836     // assert packet is complete
837     if (acl_length + 4 != size){
838         log_error("hci.c: acl_handler called with ACL packet of wrong size %d, expected %u => dropping packet", size, acl_length + 4);
839         return;
840     }
841 
842 #ifdef ENABLE_CLASSIC
843     // update idle timestamp
844     hci_connection_timestamp(conn);
845 #endif
846 
847 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
848     hci_stack->host_completed_packets = 1;
849     conn->num_packets_completed++;
850 #endif
851 
852     // handle different packet types
853     switch (acl_flags & 0x03) {
854 
855         case 0x01: // continuation fragment
856 
857             // sanity checks
858             if (conn->acl_recombination_pos == 0) {
859                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x", con_handle);
860                 return;
861             }
862             if (conn->acl_recombination_pos + acl_length > 4 + HCI_ACL_BUFFER_SIZE){
863                 log_error( "ACL Cont Fragment to large: combined packet %u > buffer size %u for handle 0x%02x",
864                     conn->acl_recombination_pos + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
865                 conn->acl_recombination_pos = 0;
866                 return;
867             }
868 
869             // append fragment payload (header already stored)
870             memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE + conn->acl_recombination_pos], &packet[4], acl_length );
871             conn->acl_recombination_pos += acl_length;
872 
873             // log_error( "ACL Cont Fragment: acl_len %u, combined_len %u, l2cap_len %u", acl_length,
874             //        conn->acl_recombination_pos, conn->acl_recombination_length);
875 
876             // forward complete L2CAP packet if complete.
877             if (conn->acl_recombination_pos >= conn->acl_recombination_length + 4 + 4){ // pos already incl. ACL header
878                 hci_emit_acl_packet(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], conn->acl_recombination_pos);
879                 // reset recombination buffer
880                 conn->acl_recombination_length = 0;
881                 conn->acl_recombination_pos = 0;
882             }
883             break;
884 
885         case 0x02: { // first fragment
886 
887             // sanity check
888             if (conn->acl_recombination_pos) {
889                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x, dropping stale fragments", con_handle);
890                 conn->acl_recombination_pos = 0;
891             }
892 
893             // peek into L2CAP packet!
894             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
895 
896             // log_info( "ACL First Fragment: acl_len %u, l2cap_len %u", acl_length, l2cap_length);
897 
898             // compare fragment size to L2CAP packet size
899             if (acl_length >= l2cap_length + 4){
900                 // forward fragment as L2CAP packet
901                 hci_emit_acl_packet(packet, acl_length + 4);
902             } else {
903 
904                 if (acl_length > HCI_ACL_BUFFER_SIZE){
905                     log_error( "ACL First Fragment to large: fragment %u > buffer size %u for handle 0x%02x",
906                         4 + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
907                     return;
908                 }
909 
910                 // store first fragment and tweak acl length for complete package
911                 memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], packet, acl_length + 4);
912                 conn->acl_recombination_pos    = acl_length + 4;
913                 conn->acl_recombination_length = l2cap_length;
914                 little_endian_store_16(conn->acl_recombination_buffer, HCI_INCOMING_PRE_BUFFER_SIZE + 2, l2cap_length +4);
915             }
916             break;
917 
918         }
919         default:
920             log_error( "hci.c: acl_handler called with invalid packet boundary flags %u", acl_flags & 0x03);
921             return;
922     }
923 
924     // execute main loop
925     hci_run();
926 }
927 
928 static void hci_shutdown_connection(hci_connection_t *conn){
929     log_info("Connection closed: handle 0x%x, %s", conn->con_handle, bd_addr_to_str(conn->address));
930 
931 #ifdef ENABLE_CLASSIC
932 #ifdef ENABLE_SCO_OVER_HCI
933     int addr_type = conn->address_type;
934 #endif
935 #endif
936 
937     btstack_run_loop_remove_timer(&conn->timeout);
938 
939     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
940     btstack_memory_hci_connection_free( conn );
941 
942     // now it's gone
943     hci_emit_nr_connections_changed();
944 
945 #ifdef ENABLE_CLASSIC
946 #ifdef ENABLE_SCO_OVER_HCI
947     // update SCO
948     if (addr_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
949         hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
950     }
951 #endif
952 #endif
953 }
954 
955 #ifdef ENABLE_CLASSIC
956 
957 static const uint16_t packet_type_sizes[] = {
958     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
959     HCI_ACL_DH1_SIZE, 0, 0, 0,
960     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
961     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
962 };
963 static const uint8_t  packet_type_feature_requirement_bit[] = {
964      0, // 3 slot packets
965      1, // 5 slot packets
966     25, // EDR 2 mpbs
967     26, // EDR 3 mbps
968     39, // 3 slot EDR packts
969     40, // 5 slot EDR packet
970 };
971 static const uint16_t packet_type_feature_packet_mask[] = {
972     0x0f00, // 3 slot packets
973     0xf000, // 5 slot packets
974     0x1102, // EDR 2 mpbs
975     0x2204, // EDR 3 mbps
976     0x0300, // 3 slot EDR packts
977     0x3000, // 5 slot EDR packet
978 };
979 
980 static uint16_t hci_acl_packet_types_for_buffer_size_and_local_features(uint16_t buffer_size, uint8_t * local_supported_features){
981     // enable packet types based on size
982     uint16_t packet_types = 0;
983     unsigned int i;
984     for (i=0;i<16;i++){
985         if (packet_type_sizes[i] == 0) continue;
986         if (packet_type_sizes[i] <= buffer_size){
987             packet_types |= 1 << i;
988         }
989     }
990     // disable packet types due to missing local supported features
991     for (i=0;i<sizeof(packet_type_feature_requirement_bit);i++){
992         unsigned int bit_idx = packet_type_feature_requirement_bit[i];
993         int feature_set = (local_supported_features[bit_idx >> 3] & (1<<(bit_idx & 7))) != 0;
994         if (feature_set) continue;
995         log_info("Features bit %02u is not set, removing packet types 0x%04x", bit_idx, packet_type_feature_packet_mask[i]);
996         packet_types &= ~packet_type_feature_packet_mask[i];
997     }
998     // flip bits for "may not be used"
999     packet_types ^= 0x3306;
1000     return packet_types;
1001 }
1002 
1003 uint16_t hci_usable_acl_packet_types(void){
1004     return hci_stack->packet_types;
1005 }
1006 #endif
1007 
1008 uint8_t* hci_get_outgoing_packet_buffer(void){
1009     // hci packet buffer is >= acl data packet length
1010     return hci_stack->hci_packet_buffer;
1011 }
1012 
1013 uint16_t hci_max_acl_data_packet_length(void){
1014     return hci_stack->acl_data_packet_length;
1015 }
1016 
1017 #ifdef ENABLE_CLASSIC
1018 int hci_extended_sco_link_supported(void){
1019     // No. 31, byte 3, bit 7
1020     return (hci_stack->local_supported_features[3] & (1 << 7)) != 0;
1021 }
1022 #endif
1023 
1024 int hci_non_flushable_packet_boundary_flag_supported(void){
1025     // No. 54, byte 6, bit 6
1026     return (hci_stack->local_supported_features[6] & (1 << 6)) != 0;
1027 }
1028 
1029 static int gap_ssp_supported(void){
1030     // No. 51, byte 6, bit 3
1031     return (hci_stack->local_supported_features[6] & (1 << 3)) != 0;
1032 }
1033 
1034 static int hci_classic_supported(void){
1035 #ifdef ENABLE_CLASSIC
1036     // No. 37, byte 4, bit 5, = No BR/EDR Support
1037     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
1038 #else
1039     return 0;
1040 #endif
1041 }
1042 
1043 static int hci_le_supported(void){
1044 #ifdef ENABLE_BLE
1045     // No. 37, byte 4, bit 6 = LE Supported (Controller)
1046     return (hci_stack->local_supported_features[4] & (1 << 6)) != 0;
1047 #else
1048     return 0;
1049 #endif
1050 }
1051 
1052 #ifdef ENABLE_BLE
1053 
1054 /**
1055  * @brief Get addr type and address used for LE in Advertisements, Scan Responses,
1056  */
1057 void gap_le_get_own_address(uint8_t * addr_type, bd_addr_t addr){
1058     *addr_type = hci_stack->le_own_addr_type;
1059     if (hci_stack->le_own_addr_type){
1060         memcpy(addr, hci_stack->le_random_address, 6);
1061     } else {
1062         memcpy(addr, hci_stack->local_bd_addr, 6);
1063     }
1064 }
1065 
1066 #ifdef ENABLE_LE_CENTRAL
1067 void le_handle_advertisement_report(uint8_t *packet, uint16_t size){
1068 
1069     int offset = 3;
1070     int num_reports = packet[offset];
1071     offset += 1;
1072 
1073     int i;
1074     // log_info("HCI: handle adv report with num reports: %d", num_reports);
1075     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
1076     for (i=0; i<num_reports && offset < size;i++){
1077         // sanity checks on data_length:
1078         uint8_t data_length = packet[offset + 8];
1079         if (data_length > LE_ADVERTISING_DATA_SIZE) return;
1080         if (offset + 9 + data_length + 1 > size)    return;
1081         // setup event
1082         uint8_t event_size = 10 + data_length;
1083         int pos = 0;
1084         event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
1085         event[pos++] = event_size;
1086         memcpy(&event[pos], &packet[offset], 1+1+6); // event type + address type + address
1087         offset += 8;
1088         pos += 8;
1089         event[pos++] = packet[offset + 1 + data_length]; // rssi
1090         event[pos++] = data_length;
1091         offset++;
1092         memcpy(&event[pos], &packet[offset], data_length);
1093         pos +=    data_length;
1094         offset += data_length + 1; // rssi
1095         hci_emit_event(event, pos, 1);
1096     }
1097 }
1098 #endif
1099 #endif
1100 
1101 #ifdef ENABLE_BLE
1102 #ifdef ENABLE_LE_PERIPHERAL
1103 static void hci_reenable_advertisements_if_needed(void){
1104     if (!hci_stack->le_advertisements_active && hci_stack->le_advertisements_enabled){
1105         // get number of active le slave connections
1106         int num_slave_connections = 0;
1107         btstack_linked_list_iterator_t it;
1108         btstack_linked_list_iterator_init(&it, &hci_stack->connections);
1109         while (btstack_linked_list_iterator_has_next(&it)){
1110             hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
1111             log_info("state %u, role %u, le_con %u", con->state, con->role, hci_is_le_connection(con));
1112             if (con->state != OPEN) continue;
1113             if (con->role  != HCI_ROLE_SLAVE) continue;
1114             if (!hci_is_le_connection(con)) continue;
1115             num_slave_connections++;
1116         }
1117         log_info("Num LE Peripheral roles: %u of %u", num_slave_connections, hci_stack->le_max_number_peripheral_connections);
1118         if (num_slave_connections < hci_stack->le_max_number_peripheral_connections){
1119             hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
1120         }
1121     }
1122 }
1123 #endif
1124 #endif
1125 
1126 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1127 
1128 static uint32_t hci_transport_uart_get_main_baud_rate(void){
1129     if (!hci_stack->config) return 0;
1130     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1131     // Limit baud rate for Broadcom chipsets to 3 mbps
1132     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION && baud_rate > 3000000){
1133         baud_rate = 3000000;
1134     }
1135     return baud_rate;
1136 }
1137 
1138 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
1139     UNUSED(ds);
1140 
1141     switch (hci_stack->substate){
1142         case HCI_INIT_W4_SEND_RESET:
1143             log_info("Resend HCI Reset");
1144             hci_stack->substate = HCI_INIT_SEND_RESET;
1145             hci_stack->num_cmd_packets = 1;
1146             hci_run();
1147             break;
1148         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
1149             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
1150             if (hci_stack->hci_transport->reset_link){
1151                 hci_stack->hci_transport->reset_link();
1152             }
1153             // no break - explicit fallthrough to HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT
1154         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1155             log_info("Resend HCI Reset - CSR Warm Boot");
1156             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1157             hci_stack->num_cmd_packets = 1;
1158             hci_run();
1159             break;
1160         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1161             if (hci_stack->hci_transport->set_baudrate){
1162                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1163                 log_info("Local baud rate change to %"PRIu32"(timeout handler)", baud_rate);
1164                 hci_stack->hci_transport->set_baudrate(baud_rate);
1165             }
1166             // For CSR, HCI Reset is sent on new baud rate. Don't forget to reset link for H5/BCSP
1167             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
1168                 if (hci_stack->hci_transport->reset_link){
1169                     log_info("Link Reset");
1170                     hci_stack->hci_transport->reset_link();
1171                 }
1172                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1173                 hci_run();
1174             }
1175             break;
1176         case HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY:
1177             // otherwise continue
1178             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1179             hci_send_cmd(&hci_read_local_supported_commands);
1180             break;
1181         default:
1182             break;
1183     }
1184 }
1185 #endif
1186 
1187 static void hci_initializing_next_state(void){
1188     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
1189 }
1190 
1191 #if defined(ENABLE_CLASSIC) || defined(ENABLE_LE_PERIPHERAL)
1192 static void hci_replace_bd_addr_placeholder(uint8_t * data, uint16_t size){
1193     const int bd_addr_string_len = 17;
1194     int i = 0;
1195     while (i < size - bd_addr_string_len){
1196         if (memcmp(&data[i], "00:00:00:00:00:00", bd_addr_string_len)) {
1197             i++;
1198             continue;
1199         }
1200         // set real address
1201         memcpy(&data[i], bd_addr_to_str(hci_stack->local_bd_addr), bd_addr_string_len);
1202         i += bd_addr_string_len;
1203     }
1204 }
1205 #endif
1206 
1207 // assumption: hci_can_send_command_packet_now() == true
1208 static void hci_initializing_run(void){
1209     log_debug("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
1210     switch (hci_stack->substate){
1211         case HCI_INIT_SEND_RESET:
1212             hci_state_reset();
1213 
1214 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1215             // prepare reset if command complete not received in 100ms
1216             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1217             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1218             btstack_run_loop_add_timer(&hci_stack->timeout);
1219 #endif
1220             // send command
1221             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1222             hci_send_cmd(&hci_reset);
1223             break;
1224         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
1225             hci_send_cmd(&hci_read_local_version_information);
1226             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
1227             break;
1228         case HCI_INIT_SEND_READ_LOCAL_NAME:
1229             hci_send_cmd(&hci_read_local_name);
1230             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
1231             break;
1232 
1233 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1234         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1235             hci_state_reset();
1236             // prepare reset if command complete not received in 100ms
1237             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1238             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1239             btstack_run_loop_add_timer(&hci_stack->timeout);
1240             // send command
1241             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1242             hci_send_cmd(&hci_reset);
1243             break;
1244         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
1245             hci_state_reset();
1246             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1247             hci_send_cmd(&hci_reset);
1248             break;
1249         case HCI_INIT_SEND_BAUD_CHANGE: {
1250             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1251             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1252             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1253             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1254             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1255             // STLC25000D: baudrate change happens within 0.5 s after command was send,
1256             // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1257             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1258                 btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1259                 btstack_run_loop_add_timer(&hci_stack->timeout);
1260             }
1261             break;
1262         }
1263         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1264             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1265             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1266             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1267             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1268             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1269             break;
1270         }
1271         case HCI_INIT_CUSTOM_INIT:
1272             // Custom initialization
1273             if (hci_stack->chipset && hci_stack->chipset->next_command){
1274                 int valid_cmd = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1275                 if (valid_cmd){
1276                     int size = 3 + hci_stack->hci_packet_buffer[2];
1277                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1278                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1279                     switch (valid_cmd) {
1280                         case BTSTACK_CHIPSET_VALID_COMMAND:
1281                             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1282                             break;
1283                         case BTSTACK_CHIPSET_WARMSTART_REQUIRED:
1284                             // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1285                             log_info("CSR Warm Boot");
1286                             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1287                             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1288                             btstack_run_loop_add_timer(&hci_stack->timeout);
1289                             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO
1290                                 && hci_stack->config
1291                                 && hci_stack->chipset
1292                                 // && hci_stack->chipset->set_baudrate_command -- there's no such command
1293                                 && hci_stack->hci_transport->set_baudrate
1294                                 && hci_transport_uart_get_main_baud_rate()){
1295                                 hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1296                             } else {
1297                                hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1298                             }
1299                             break;
1300                         default:
1301                             // should not get here
1302                             break;
1303                     }
1304                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1305                     break;
1306                 }
1307                 log_info("Init script done");
1308 
1309                 // Init script download on Broadcom chipsets causes:
1310                 if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION
1311                 ||  hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA){
1312 
1313                     // - baud rate to reset, restore UART baud rate if needed
1314                     int need_baud_change = hci_stack->config
1315                         && hci_stack->chipset
1316                         && hci_stack->chipset->set_baudrate_command
1317                         && hci_stack->hci_transport->set_baudrate
1318                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1319                     if (need_baud_change) {
1320                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1321                         log_info("Local baud rate change to %"PRIu32" after init script (bcm)", baud_rate);
1322                         hci_stack->hci_transport->set_baudrate(baud_rate);
1323                     }
1324 
1325                     // - RTS will raise during update, but manual RTS/CTS in WICED port on RedBear Duo cannot handle this
1326                     //   -> Work around: wait a few milliseconds here.
1327                     log_info("BCM delay after init script");
1328                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1329                     btstack_run_loop_set_timer(&hci_stack->timeout, 10);
1330                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1331                     btstack_run_loop_add_timer(&hci_stack->timeout);
1332                     break;
1333                 }
1334             }
1335             // otherwise continue
1336             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1337             hci_send_cmd(&hci_read_local_supported_commands);
1338             break;
1339         case HCI_INIT_SET_BD_ADDR:
1340             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1341             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1342             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1343             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1344             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1345             break;
1346 #endif
1347 
1348         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1349             log_info("Resend hci_read_local_supported_commands after CSR Warm Boot double reset");
1350             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1351             hci_send_cmd(&hci_read_local_supported_commands);
1352             break;
1353         case HCI_INIT_READ_BD_ADDR:
1354             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1355             hci_send_cmd(&hci_read_bd_addr);
1356             break;
1357         case HCI_INIT_READ_BUFFER_SIZE:
1358             hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1359             hci_send_cmd(&hci_read_buffer_size);
1360             break;
1361         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1362             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1363             hci_send_cmd(&hci_read_local_supported_features);
1364             break;
1365 
1366 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1367         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1368             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1369             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1370             break;
1371         case HCI_INIT_HOST_BUFFER_SIZE:
1372             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1373             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1374                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1375             break;
1376 #endif
1377 
1378         case HCI_INIT_SET_EVENT_MASK:
1379             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1380             if (hci_le_supported()){
1381                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x3FFFFFFF);
1382             } else {
1383                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1384                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x1FFFFFFF);
1385             }
1386             break;
1387 
1388 #ifdef ENABLE_CLASSIC
1389         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1390             hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1391             hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1392             break;
1393         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1394             hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1395             hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1396             break;
1397         case HCI_INIT_WRITE_DEFAULT_LINK_POLICY_SETTING:
1398             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_LINK_POLICY_SETTING;
1399             hci_send_cmd(&hci_write_default_link_policy_setting, hci_stack->default_link_policy_settings);
1400             break;
1401         case HCI_INIT_WRITE_CLASS_OF_DEVICE:
1402             hci_stack->substate = HCI_INIT_W4_WRITE_CLASS_OF_DEVICE;
1403             hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1404             break;
1405         case HCI_INIT_WRITE_LOCAL_NAME: {
1406             hci_stack->substate = HCI_INIT_W4_WRITE_LOCAL_NAME;
1407             hci_reserve_packet_buffer();
1408             uint8_t * packet = hci_stack->hci_packet_buffer;
1409             // construct HCI Command and send
1410             uint16_t opcode = hci_write_local_name.opcode;
1411             hci_stack->last_cmd_opcode = opcode;
1412             packet[0] = opcode & 0xff;
1413             packet[1] = opcode >> 8;
1414             packet[2] = DEVICE_NAME_LEN;
1415             memset(&packet[3], 0, DEVICE_NAME_LEN);
1416             memcpy(&packet[3], hci_stack->local_name, strlen(hci_stack->local_name));
1417             // expand '00:00:00:00:00:00' in name with bd_addr
1418             hci_replace_bd_addr_placeholder(&packet[3], DEVICE_NAME_LEN);
1419             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + DEVICE_NAME_LEN);
1420             break;
1421         }
1422         case HCI_INIT_WRITE_EIR_DATA: {
1423             hci_stack->substate = HCI_INIT_W4_WRITE_EIR_DATA;
1424             hci_reserve_packet_buffer();
1425             uint8_t * packet = hci_stack->hci_packet_buffer;
1426             // construct HCI Command and send
1427             uint16_t opcode = hci_write_extended_inquiry_response.opcode;
1428             hci_stack->last_cmd_opcode = opcode;
1429             packet[0] = opcode & 0xff;
1430             packet[1] = opcode >> 8;
1431             packet[2] = 1 + 240;
1432             packet[3] = 0;  // FEC not required
1433             if (hci_stack->eir_data){
1434                 memcpy(&packet[4], hci_stack->eir_data, 240);
1435             } else {
1436                 memset(&packet[4], 0, 240);
1437                 int name_len = strlen(hci_stack->local_name);
1438                 packet[4] = name_len + 1;
1439                 packet[5] = BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME;
1440                 memcpy(&packet[6], hci_stack->local_name, name_len);
1441             }
1442             // expand '00:00:00:00:00:00' in name with bd_addr
1443             hci_replace_bd_addr_placeholder(&packet[4], 240);
1444             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + 1 + 240);
1445             break;
1446         }
1447         case HCI_INIT_WRITE_INQUIRY_MODE:
1448             hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1449             hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1450             break;
1451         case HCI_INIT_WRITE_SCAN_ENABLE:
1452             hci_send_cmd(&hci_write_scan_enable, (hci_stack->connectable << 1) | hci_stack->discoverable); // page scan
1453             hci_stack->substate = HCI_INIT_W4_WRITE_SCAN_ENABLE;
1454             break;
1455         // only sent if ENABLE_SCO_OVER_HCI is defined
1456         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1457             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1458             hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1459             break;
1460         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1461             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1462             hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1463             break;
1464         // only sent if ENABLE_SCO_OVER_HCI and manufacturer is Broadcom
1465         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1466             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1467             log_info("BCM: Route SCO data via HCI transport");
1468             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1469             break;
1470 
1471 #endif
1472 #ifdef ENABLE_BLE
1473         // LE INIT
1474         case HCI_INIT_LE_READ_BUFFER_SIZE:
1475             hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1476             hci_send_cmd(&hci_le_read_buffer_size);
1477             break;
1478         case HCI_INIT_LE_SET_EVENT_MASK:
1479             hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
1480             hci_send_cmd(&hci_le_set_event_mask, 0x809FF, 0x0); // bits 0-8, 11, 19
1481             break;
1482         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1483             // LE Supported Host = 1, Simultaneous Host = 0
1484             hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1485             hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1486             break;
1487 #endif
1488 
1489 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1490         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1491             hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1492             hci_send_cmd(&hci_le_read_maximum_data_length);
1493             break;
1494         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1495             hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1496             hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1497             break;
1498 #endif
1499 
1500 #ifdef ENABLE_LE_CENTRAL
1501         case HCI_INIT_READ_WHITE_LIST_SIZE:
1502             hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1503             hci_send_cmd(&hci_le_read_white_list_size);
1504             break;
1505         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1506             // LE Scan Parameters: active scanning, 300 ms interval, 30 ms window, own address type, accept all advs
1507             hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1508             hci_send_cmd(&hci_le_set_scan_parameters, 1, 0x1e0, 0x30, hci_stack->le_own_addr_type, 0);
1509             break;
1510 #endif
1511         default:
1512             return;
1513     }
1514 }
1515 
1516 static void hci_init_done(void){
1517     // done. tell the app
1518     log_info("hci_init_done -> HCI_STATE_WORKING");
1519     hci_stack->state = HCI_STATE_WORKING;
1520     hci_emit_state();
1521     hci_run();
1522 }
1523 
1524 static void hci_initializing_event_handler(uint8_t * packet, uint16_t size){
1525 
1526     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
1527 
1528     uint8_t command_completed = 0;
1529 
1530     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1531         uint16_t opcode = little_endian_read_16(packet,3);
1532         if (opcode == hci_stack->last_cmd_opcode){
1533             command_completed = 1;
1534             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1535         } else {
1536             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1537         }
1538     }
1539 
1540     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1541         uint8_t  status = packet[2];
1542         uint16_t opcode = little_endian_read_16(packet,4);
1543         if (opcode == hci_stack->last_cmd_opcode){
1544             if (status){
1545                 command_completed = 1;
1546                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1547             } else {
1548                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1549             }
1550         } else {
1551             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1552         }
1553     }
1554 
1555 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1556 
1557     // Vendor == CSR
1558     if (hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT && hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC){
1559         // TODO: track actual command
1560         command_completed = 1;
1561     }
1562 
1563     // Vendor == Toshiba
1564     if (hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE && hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC){
1565         // TODO: track actual command
1566         command_completed = 1;
1567         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
1568         hci_stack->num_cmd_packets = 1;
1569     }
1570 
1571     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1572     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1573     //
1574     // HCI Reset
1575     // Timeout 100 ms
1576     // HCI Reset
1577     // Command Complete Reset
1578     // HCI Read Local Version Information
1579     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1580     // hang...
1581     //
1582     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1583     if (!command_completed
1584             && hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE
1585             && hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION){
1586 
1587         uint16_t opcode = little_endian_read_16(packet,3);
1588         if (opcode == hci_reset.opcode){
1589             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1590             return;
1591         }
1592     }
1593 
1594     // CSR & H5
1595     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1596     if (!command_completed
1597             && hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE
1598             && hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS){
1599 
1600         uint16_t opcode = little_endian_read_16(packet,3);
1601         if (opcode == hci_reset.opcode){
1602             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1603             return;
1604         }
1605     }
1606 
1607     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1608     // fix: Correct substate and behave as command below
1609     if (command_completed){
1610         switch (hci_stack->substate){
1611             case HCI_INIT_SEND_RESET:
1612                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1613                 break;
1614             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1615                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1616                 break;
1617             default:
1618                 break;
1619         }
1620     }
1621 
1622 #endif
1623 
1624     if (!command_completed) return;
1625 
1626     int need_baud_change = 0;
1627     int need_addr_change = 0;
1628 
1629 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1630     need_baud_change = hci_stack->config
1631                         && hci_stack->chipset
1632                         && hci_stack->chipset->set_baudrate_command
1633                         && hci_stack->hci_transport->set_baudrate
1634                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1635 
1636     need_addr_change = hci_stack->custom_bd_addr_set
1637                         && hci_stack->chipset
1638                         && hci_stack->chipset->set_bd_addr_command;
1639 #endif
1640 
1641     switch(hci_stack->substate){
1642 
1643 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1644         case HCI_INIT_SEND_RESET:
1645             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1646             // fix: just correct substate and behave as command below
1647             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1648             btstack_run_loop_remove_timer(&hci_stack->timeout);
1649             break;
1650         case HCI_INIT_W4_SEND_RESET:
1651             btstack_run_loop_remove_timer(&hci_stack->timeout);
1652             break;
1653         case HCI_INIT_W4_SEND_READ_LOCAL_NAME:
1654             log_info("Received local name, need baud change %d", need_baud_change);
1655             if (need_baud_change){
1656                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE;
1657                 return;
1658             }
1659             // skip baud change
1660             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1661             return;
1662         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1663             // for STLC2500D, baud rate change already happened.
1664             // for others, baud rate gets changed now
1665             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1666                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1667                 log_info("Local baud rate change to %"PRIu32"(w4_send_baud_change)", baud_rate);
1668                 hci_stack->hci_transport->set_baudrate(baud_rate);
1669             }
1670             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1671             return;
1672         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1673             btstack_run_loop_remove_timer(&hci_stack->timeout);
1674             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1675             return;
1676         case HCI_INIT_W4_CUSTOM_INIT:
1677             // repeat custom init
1678             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1679             return;
1680 #else
1681         case HCI_INIT_W4_SEND_RESET:
1682             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1683             return ;
1684 #endif
1685 
1686         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1687             if (need_baud_change &&
1688               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
1689                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
1690                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1691                 return;
1692             }
1693             if (need_addr_change){
1694                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1695                 return;
1696             }
1697             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1698             return;
1699 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1700         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1701             if (need_baud_change){
1702                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1703                 log_info("Local baud rate change to %"PRIu32"(w4_send_baud_change_bcm))", baud_rate);
1704                 hci_stack->hci_transport->set_baudrate(baud_rate);
1705             }
1706             if (need_addr_change){
1707                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1708                 return;
1709             }
1710             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1711             return;
1712         case HCI_INIT_W4_SET_BD_ADDR:
1713             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
1714             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
1715             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
1716                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1717                 return;
1718             }
1719             // skipping st warm boot
1720             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1721             return;
1722         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
1723             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1724             return;
1725 #endif
1726         case HCI_INIT_W4_READ_BD_ADDR:
1727             // only read buffer size if supported
1728             if (hci_stack->local_supported_commands[0] & 0x01) {
1729                 hci_stack->substate = HCI_INIT_READ_BUFFER_SIZE;
1730                 return;
1731             }
1732             // skipping read buffer size
1733             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES;
1734             return;
1735         case HCI_INIT_W4_SET_EVENT_MASK:
1736             // skip Classic init commands for LE only chipsets
1737             if (!hci_classic_supported()){
1738 #ifdef ENABLE_BLE
1739                 if (hci_le_supported()){
1740                     hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE; // skip all classic command
1741                     return;
1742                 }
1743 #endif
1744                 log_error("Neither BR/EDR nor LE supported");
1745                 hci_init_done();
1746                 return;
1747             }
1748             if (!gap_ssp_supported()){
1749                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1750                 return;
1751             }
1752             break;
1753 #ifdef ENABLE_BLE
1754         case HCI_INIT_W4_LE_READ_BUFFER_SIZE:
1755             // skip write le host if not supported (e.g. on LE only EM9301)
1756             if (hci_stack->local_supported_commands[0] & 0x02) break;
1757             hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1758             return;
1759 
1760 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1761         case HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED:
1762             log_info("Supported commands %x", hci_stack->local_supported_commands[0] & 0x30);
1763             if ((hci_stack->local_supported_commands[0] & 0x30) == 0x30){
1764                 hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1765                 return;
1766             }
1767             // explicit fall through to reduce repetitions
1768 
1769 #ifdef ENABLE_LE_CENTRAL
1770             hci_stack->substate = HCI_INIT_READ_WHITE_LIST_SIZE;
1771 #else
1772             hci_init_done();
1773 #endif
1774             return;
1775 #endif  /* ENABLE_LE_DATA_LENGTH_EXTENSION */
1776 
1777 #endif  /* ENABLE_BLE */
1778 
1779 #ifdef ENABLE_SCO_OVER_HCI
1780         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1781             // skip write synchronous flow control if not supported
1782             if (hci_stack->local_supported_commands[0] & 0x04) break;
1783             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1784             // explicit fall through to reduce repetitions
1785 
1786         case HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1787             // skip write default erroneous data reporting if not supported
1788             if (hci_stack->local_supported_commands[0] & 0x08) break;
1789             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1790             // explicit fall through to reduce repetitions
1791 
1792         case HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1793             // skip bcm set sco pcm config on non-Broadcom chipsets
1794             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) break;
1795             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1796             // explicit fall through to reduce repetitions
1797 
1798         case HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT:
1799             if (!hci_le_supported()){
1800                 // SKIP LE init for Classic only configuration
1801                 hci_init_done();
1802                 return;
1803             }
1804             break;
1805 
1806 #else /* !ENABLE_SCO_OVER_HCI */
1807 
1808         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1809 #ifdef ENABLE_BLE
1810             if (hci_le_supported()){
1811                 hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE;
1812                 return;
1813             }
1814 #endif
1815             // SKIP LE init for Classic only configuration
1816             hci_init_done();
1817             return;
1818 #endif /* ENABLE_SCO_OVER_HCI */
1819 
1820 // avoid compile error due to duplicate cases: HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT == HCI_INIT_DONE-1
1821 #if defined(ENABLE_BLE) || defined(ENABLE_LE_DATA_LENGTH_EXTENSION) || defined(ENABLE_LE_CENTRAL)
1822         // Response to command before init done state -> init done
1823         case (HCI_INIT_DONE-1):
1824             hci_init_done();
1825             return;
1826 #endif
1827 
1828         default:
1829             break;
1830     }
1831     hci_initializing_next_state();
1832 }
1833 
1834 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
1835     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
1836     bd_addr_t bd_address;
1837     memcpy(&bd_address, conn->address, 6);
1838 
1839 #ifdef ENABLE_CLASSIC
1840     // cache needed data
1841     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
1842 #endif
1843 
1844     // connection failed, remove entry
1845     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1846     btstack_memory_hci_connection_free( conn );
1847 
1848 #ifdef ENABLE_CLASSIC
1849     // notify client if dedicated bonding
1850     if (notify_dedicated_bonding_failed){
1851         log_info("hci notify_dedicated_bonding_failed");
1852         hci_emit_dedicated_bonding_result(bd_address, status);
1853     }
1854 
1855     // if authentication error, also delete link key
1856     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
1857         gap_drop_link_key_for_bd_addr(bd_address);
1858     }
1859 #endif
1860 }
1861 
1862 static void event_handler(uint8_t *packet, int size){
1863 
1864     uint16_t event_length = packet[1];
1865 
1866     // assert packet is complete
1867     if (size != event_length + 2){
1868         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
1869         return;
1870     }
1871 
1872     bd_addr_t addr;
1873     bd_addr_type_t addr_type;
1874     hci_con_handle_t handle;
1875     hci_connection_t * conn;
1876     int i;
1877     int create_connection_cmd;
1878 
1879 #ifdef ENABLE_CLASSIC
1880     uint8_t link_type;
1881 #endif
1882 
1883     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
1884 
1885     switch (hci_event_packet_get_type(packet)) {
1886 
1887         case HCI_EVENT_COMMAND_COMPLETE:
1888             // get num cmd packets - limit to 1 to reduce complexity
1889             hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
1890 
1891             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_name)){
1892                 if (packet[5]) break;
1893                 // terminate, name 248 chars
1894                 packet[6+248] = 0;
1895                 log_info("local name: %s", &packet[6]);
1896             }
1897             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_buffer_size)){
1898                 // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
1899                 if (hci_stack->state == HCI_STATE_INITIALIZING){
1900                     uint16_t acl_len = little_endian_read_16(packet, 6);
1901                     uint16_t sco_len = packet[8];
1902 
1903                     // determine usable ACL/SCO payload size
1904                     hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
1905                     hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
1906 
1907                     hci_stack->acl_packets_total_num  = little_endian_read_16(packet, 9);
1908                     hci_stack->sco_packets_total_num  = little_endian_read_16(packet, 11);
1909 
1910                     log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
1911                              acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
1912                              hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
1913                 }
1914             }
1915 #ifdef ENABLE_BLE
1916             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_buffer_size)){
1917                 hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
1918                 hci_stack->le_acl_packets_total_num  = packet[8];
1919                 // determine usable ACL payload size
1920                 if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
1921                     hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
1922                 }
1923                 log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
1924             }
1925 #endif
1926 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1927             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_maximum_data_length)){
1928                 hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
1929                 hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
1930                 log_info("hci_le_read_maximum_data_length: tx octets %u, tx time %u us", hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1931             }
1932 #endif
1933 #ifdef ENABLE_LE_CENTRAL
1934             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_white_list_size)){
1935                 hci_stack->le_whitelist_capacity = packet[6];
1936                 log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
1937             }
1938 #endif
1939             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_bd_addr)) {
1940                 reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1],
1941 				hci_stack->local_bd_addr);
1942                 log_info("Local Address, Status: 0x%02x: Addr: %s",
1943                     packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE], bd_addr_to_str(hci_stack->local_bd_addr));
1944 #ifdef ENABLE_CLASSIC
1945                 if (hci_stack->link_key_db){
1946                     hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
1947                 }
1948 #endif
1949             }
1950 #ifdef ENABLE_CLASSIC
1951             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)){
1952                 hci_emit_discoverable_enabled(hci_stack->discoverable);
1953             }
1954             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_inquiry_cancel)){
1955                 if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
1956                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
1957                     uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
1958                     hci_emit_event(event, sizeof(event), 1);
1959                 }
1960             }
1961 #endif
1962 
1963             // Note: HCI init checks
1964             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_supported_features)){
1965                 memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 8);
1966 
1967 #ifdef ENABLE_CLASSIC
1968                 // determine usable ACL packet types based on host buffer size and supported features
1969                 hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
1970                 log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
1971 #endif
1972                 // Classic/LE
1973                 log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
1974             }
1975             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_version_information)){
1976                 // hci_stack->hci_version    = little_endian_read_16(packet, 4);
1977                 // hci_stack->hci_revision   = little_endian_read_16(packet, 6);
1978                 // hci_stack->lmp_version    = little_endian_read_16(packet, 8);
1979                 hci_stack->manufacturer   = little_endian_read_16(packet, 10);
1980                 // hci_stack->lmp_subversion = little_endian_read_16(packet, 12);
1981                 log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
1982             }
1983             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_supported_commands)){
1984                 hci_stack->local_supported_commands[0] =
1985                     (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+14] & 0x80) >> 7 |  // bit 0 = Octet 14, bit 7 / Read Buffer Size
1986                     (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+24] & 0x40) >> 5 |  // bit 1 = Octet 24, bit 6 / Write Le Host Supported
1987                     (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+10] & 0x10) >> 2 |  // bit 2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
1988                     (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+18] & 0x08)      |  // bit 3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
1989                     (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+34] & 0x01) << 4 |  // bit 4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
1990                     (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+35] & 0x08) << 2 |  // bit 5 = Octet 35, bit 3 / LE Read Maximum Data Length
1991                     (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+35] & 0x20) << 1;   // bit 6 = Octet 35, bit 5 / LE Set Default PHY
1992                     log_info("Local supported commands summary 0x%02x", hci_stack->local_supported_commands[0]);
1993             }
1994 #ifdef ENABLE_CLASSIC
1995             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_synchronous_flow_control_enable)){
1996                 if (packet[5] == 0){
1997                     hci_stack->synchronous_flow_control_enabled = 1;
1998                 }
1999             }
2000 #endif
2001             break;
2002 
2003         case HCI_EVENT_COMMAND_STATUS:
2004             // get num cmd packets - limit to 1 to reduce complexity
2005             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2006 
2007             // check command status to detected failed outgoing connections
2008             create_connection_cmd = 0;
2009 #ifdef ENABLE_CLASSIC
2010             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2011                 create_connection_cmd = 1;
2012             }
2013 #endif
2014 #ifdef ENABLE_LE_CENTRAL
2015             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2016                 create_connection_cmd = 1;
2017             }
2018 #endif
2019             if (create_connection_cmd) {
2020                 uint8_t status = hci_event_command_status_get_status(packet);
2021                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, hci_stack->outgoing_addr_type);
2022                 log_info("command status (create connection), status %x, connection %p, addr %s, type %x", status, conn, bd_addr_to_str(hci_stack->outgoing_addr), hci_stack->outgoing_addr_type);
2023 
2024                 // reset outgoing address info
2025                 memset(hci_stack->outgoing_addr, 0, 6);
2026                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2027 
2028                 // error => outgoing connection failed
2029                 if ((conn != NULL) && (status != 0)){
2030                     hci_handle_connection_failed(conn, status);
2031                 }
2032             }
2033             break;
2034 
2035         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2036             int offset = 3;
2037             for (i=0; i<packet[2];i++){
2038                 handle = little_endian_read_16(packet, offset) & 0x0fff;
2039                 offset += 2;
2040                 uint16_t num_packets = little_endian_read_16(packet, offset);
2041                 offset += 2;
2042 
2043                 conn = hci_connection_for_handle(handle);
2044                 if (!conn){
2045                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2046                     continue;
2047                 }
2048 
2049                 if (conn->num_packets_sent >= num_packets){
2050                     conn->num_packets_sent -= num_packets;
2051                 } else {
2052                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2053                     conn->num_packets_sent = 0;
2054                 }
2055                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2056 
2057 #ifdef ENABLE_CLASSIC
2058                 // For SCO, we do the can_send_now_check here
2059                 hci_notify_if_sco_can_send_now();
2060 #endif
2061             }
2062             break;
2063         }
2064 
2065 #ifdef ENABLE_CLASSIC
2066         case HCI_EVENT_INQUIRY_COMPLETE:
2067             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2068                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2069                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2070                 hci_emit_event(event, sizeof(event), 1);
2071             }
2072             break;
2073         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2074             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2075                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2076             }
2077             break;
2078         case HCI_EVENT_CONNECTION_REQUEST:
2079             reverse_bd_addr(&packet[2], addr);
2080             // TODO: eval COD 8-10
2081             link_type = packet[11];
2082             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), link_type);
2083             addr_type = link_type == 1 ? BD_ADDR_TYPE_CLASSIC : BD_ADDR_TYPE_SCO;
2084             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2085             if (!conn) {
2086                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2087             }
2088             if (!conn) {
2089                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2090                 hci_stack->decline_reason = 0x0d;
2091                 bd_addr_copy(hci_stack->decline_addr, addr);
2092                 break;
2093             }
2094             conn->role  = HCI_ROLE_SLAVE;
2095             conn->state = RECEIVED_CONNECTION_REQUEST;
2096             // store info about eSCO
2097             if (link_type == 0x02){
2098                 conn->remote_supported_feature_eSCO = 1;
2099             }
2100             hci_run();
2101             break;
2102 
2103         case HCI_EVENT_CONNECTION_COMPLETE:
2104             // Connection management
2105             reverse_bd_addr(&packet[5], addr);
2106             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2107             addr_type = BD_ADDR_TYPE_CLASSIC;
2108             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2109             if (conn) {
2110                 if (!packet[2]){
2111                     conn->state = OPEN;
2112                     conn->con_handle = little_endian_read_16(packet, 3);
2113                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES;
2114 
2115                     // restart timer
2116                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2117                     btstack_run_loop_add_timer(&conn->timeout);
2118 
2119                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2120 
2121                     hci_emit_nr_connections_changed();
2122                 } else {
2123                     // connection failed
2124                     hci_handle_connection_failed(conn, packet[2]);
2125                 }
2126             }
2127             break;
2128 
2129         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2130             reverse_bd_addr(&packet[5], addr);
2131             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2132             if (packet[2]){
2133                 // connection failed
2134                 break;
2135             }
2136             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2137             if (!conn) {
2138                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2139             }
2140             if (!conn) {
2141                 break;
2142             }
2143             conn->state = OPEN;
2144             conn->con_handle = little_endian_read_16(packet, 3);
2145 
2146 #ifdef ENABLE_SCO_OVER_HCI
2147             // update SCO
2148             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2149                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2150             }
2151             // trigger can send now
2152             if (hci_have_usb_transport()){
2153                 hci_stack->sco_can_send_now = 1;
2154             }
2155 #endif
2156             break;
2157 
2158         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2159             handle = little_endian_read_16(packet, 3);
2160             conn = hci_connection_for_handle(handle);
2161             if (!conn) break;
2162             if (!packet[2]){
2163                 uint8_t * features = &packet[5];
2164                 if (features[6] & (1 << 3)){
2165                     conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP;
2166                 }
2167                 if (features[3] & (1<<7)){
2168                     conn->remote_supported_feature_eSCO = 1;
2169                 }
2170             }
2171             conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
2172             log_info("HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE, bonding flags %x, eSCO %u", conn->bonding_flags, conn->remote_supported_feature_eSCO);
2173             if (conn->bonding_flags & BONDING_DEDICATED){
2174                 conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2175             }
2176             break;
2177 
2178         case HCI_EVENT_LINK_KEY_REQUEST:
2179             log_info("HCI_EVENT_LINK_KEY_REQUEST");
2180             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_REQUEST);
2181             // non-bondable mode: link key negative reply will be sent by HANDLE_LINK_KEY_REQUEST
2182             if (hci_stack->bondable && !hci_stack->link_key_db) break;
2183             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], HANDLE_LINK_KEY_REQUEST);
2184             hci_run();
2185             // request handled by hci_run() as HANDLE_LINK_KEY_REQUEST gets set
2186             return;
2187 
2188         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2189             reverse_bd_addr(&packet[2], addr);
2190             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
2191             if (!conn) break;
2192             conn->authentication_flags |= RECV_LINK_KEY_NOTIFICATION;
2193             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2194             // Change Connection Encryption keeps link key type
2195             if (link_key_type != CHANGED_COMBINATION_KEY){
2196                 conn->link_key_type = link_key_type;
2197             }
2198             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2199             // still forward event to allow dismiss of pairing dialog
2200             break;
2201         }
2202 
2203         case HCI_EVENT_PIN_CODE_REQUEST:
2204             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], LEGACY_PAIRING_ACTIVE);
2205             // non-bondable mode: pin code negative reply will be sent
2206             if (!hci_stack->bondable){
2207                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], DENY_PIN_CODE_REQUEST);
2208                 hci_run();
2209                 return;
2210             }
2211             // PIN CODE REQUEST means the link key request didn't succee -> delete stored link key
2212             if (!hci_stack->link_key_db) break;
2213             hci_event_pin_code_request_get_bd_addr(packet, addr);
2214             hci_stack->link_key_db->delete_link_key(addr);
2215             break;
2216 
2217         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2218             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_IO_CAPABILITIES_REQUEST);
2219             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_IO_CAPABILITIES_REPLY);
2220             break;
2221 
2222         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2223             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2224             if (!hci_stack->ssp_auto_accept) break;
2225             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_CONFIRM_REPLY);
2226             break;
2227 
2228         case HCI_EVENT_USER_PASSKEY_REQUEST:
2229             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2230             if (!hci_stack->ssp_auto_accept) break;
2231             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_PASSKEY_REPLY);
2232             break;
2233         case HCI_EVENT_MODE_CHANGE:
2234             handle = hci_event_mode_change_get_handle(packet);
2235             conn = hci_connection_for_handle(handle);
2236             if (!conn) break;
2237             conn->connection_mode = hci_event_mode_change_get_mode(packet);
2238             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
2239             break;
2240 #endif
2241 
2242         case HCI_EVENT_ENCRYPTION_CHANGE:
2243             handle = little_endian_read_16(packet, 3);
2244             conn = hci_connection_for_handle(handle);
2245             if (!conn) break;
2246             if (packet[2] == 0) {
2247                 if (packet[5]){
2248                     conn->authentication_flags |= CONNECTION_ENCRYPTED;
2249                 } else {
2250                     conn->authentication_flags &= ~CONNECTION_ENCRYPTED;
2251                 }
2252             }
2253 #ifdef ENABLE_CLASSIC
2254             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2255 #endif
2256             break;
2257 
2258 #ifdef ENABLE_CLASSIC
2259         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
2260             handle = little_endian_read_16(packet, 3);
2261             conn = hci_connection_for_handle(handle);
2262             if (!conn) break;
2263 
2264             // dedicated bonding: send result and disconnect
2265             if (conn->bonding_flags & BONDING_DEDICATED){
2266                 conn->bonding_flags &= ~BONDING_DEDICATED;
2267                 conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
2268                 conn->bonding_status = packet[2];
2269                 break;
2270             }
2271 
2272             if (packet[2] == 0 && gap_security_level_for_link_key_type(conn->link_key_type) >= conn->requested_security_level){
2273                 // link key sufficient for requested security
2274                 conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
2275                 break;
2276             }
2277             // not enough
2278             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2279             break;
2280 #endif
2281 
2282         // HCI_EVENT_DISCONNECTION_COMPLETE
2283         // has been split, to first notify stack before shutting connection down
2284         // see end of function, too.
2285         case HCI_EVENT_DISCONNECTION_COMPLETE:
2286             if (packet[2]) break;   // status != 0
2287             handle = little_endian_read_16(packet, 3);
2288             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
2289             if (hci_stack->acl_fragmentation_total_size > 0) {
2290                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
2291                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0;
2292                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
2293                     hci_stack->acl_fragmentation_total_size = 0;
2294                     hci_stack->acl_fragmentation_pos = 0;
2295                     if (release_buffer){
2296                         hci_release_packet_buffer();
2297                     }
2298                 }
2299             }
2300 
2301             // re-enable advertisements for le connections if active
2302             conn = hci_connection_for_handle(handle);
2303             if (!conn) break;
2304             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
2305 #ifdef ENABLE_BLE
2306 #ifdef ENABLE_LE_PERIPHERAL
2307             if (hci_is_le_connection(conn)){
2308                 hci_reenable_advertisements_if_needed();
2309             }
2310 #endif
2311 #endif
2312             break;
2313 
2314         case HCI_EVENT_HARDWARE_ERROR:
2315             log_error("Hardware Error: 0x%02x", packet[2]);
2316             if (hci_stack->hardware_error_callback){
2317                 (*hci_stack->hardware_error_callback)(packet[2]);
2318             } else {
2319                 // if no special requests, just reboot stack
2320                 hci_power_control_off();
2321                 hci_power_control_on();
2322             }
2323             break;
2324 
2325 #ifdef ENABLE_CLASSIC
2326         case HCI_EVENT_ROLE_CHANGE:
2327             if (packet[2]) break;   // status != 0
2328             reverse_bd_addr(&packet[3], addr);
2329             addr_type = BD_ADDR_TYPE_CLASSIC;
2330             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2331             if (!conn) break;
2332             conn->role = packet[9];
2333             break;
2334 #endif
2335 
2336         case HCI_EVENT_TRANSPORT_PACKET_SENT:
2337             // release packet buffer only for asynchronous transport and if there are not further fragements
2338             if (hci_transport_synchronous()) {
2339                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
2340                 return; // instead of break: to avoid re-entering hci_run()
2341             }
2342             hci_stack->acl_fragmentation_tx_active = 0;
2343             if (hci_stack->acl_fragmentation_total_size) break;
2344             hci_release_packet_buffer();
2345 
2346             // L2CAP receives this event via the hci_emit_event below
2347 
2348 #ifdef ENABLE_CLASSIC
2349             // For SCO, we do the can_send_now_check here
2350             hci_notify_if_sco_can_send_now();
2351 #endif
2352             break;
2353 
2354 #ifdef ENABLE_CLASSIC
2355         case HCI_EVENT_SCO_CAN_SEND_NOW:
2356             // For SCO, we do the can_send_now_check here
2357             hci_stack->sco_can_send_now = 1;
2358             hci_notify_if_sco_can_send_now();
2359             return;
2360 
2361         // explode inquriy results for easier consumption
2362         case HCI_EVENT_INQUIRY_RESULT:
2363         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
2364         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
2365             gap_inquiry_explode(packet);
2366             break;
2367 #endif
2368 
2369 #ifdef ENABLE_BLE
2370         case HCI_EVENT_LE_META:
2371             switch (packet[2]){
2372 #ifdef ENABLE_LE_CENTRAL
2373                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
2374                     // log_info("advertising report received");
2375                     if (!hci_stack->le_scanning_enabled) break;
2376                     le_handle_advertisement_report(packet, size);
2377                     break;
2378 #endif
2379                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
2380                     // Connection management
2381                     reverse_bd_addr(&packet[8], addr);
2382                     addr_type = (bd_addr_type_t)packet[7];
2383                     log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2384                     conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2385 
2386 #ifdef ENABLE_LE_CENTRAL
2387                     // if auto-connect, remove from whitelist in both roles
2388                     if (hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST){
2389                         hci_remove_from_whitelist(addr_type, addr);
2390                     }
2391                     // handle error: error is reported only to the initiator -> outgoing connection
2392                     if (packet[3]){
2393 
2394                         // handle cancelled outgoing connection
2395                         // "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2396                         //  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2397                         //  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2398                         if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2399                             conn = gap_get_outgoing_connection();
2400                         }
2401 
2402                         // outgoing connection establishment is done
2403                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2404                         // remove entry
2405                         if (conn){
2406                             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2407                             btstack_memory_hci_connection_free( conn );
2408                         }
2409                         break;
2410                     }
2411 #endif
2412                     // on success, both hosts receive connection complete event
2413                     if (packet[6] == HCI_ROLE_MASTER){
2414 #ifdef ENABLE_LE_CENTRAL
2415                         // if we're master, it was an outgoing connection and we're done with it
2416                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2417 #endif
2418                     } else {
2419 #ifdef ENABLE_LE_PERIPHERAL
2420                         // if we're slave, it was an incoming connection, advertisements have stopped
2421                         hci_stack->le_advertisements_active = 0;
2422 #endif
2423                     }
2424                     // LE connections are auto-accepted, so just create a connection if there isn't one already
2425                     if (!conn){
2426                         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2427                     }
2428                     // no memory, sorry.
2429                     if (!conn){
2430                         break;
2431                     }
2432 
2433                     conn->state = OPEN;
2434                     conn->role  = packet[6];
2435                     conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2436                     conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2437 
2438 #ifdef ENABLE_LE_PERIPHERAL
2439                     if (packet[6] == HCI_ROLE_SLAVE){
2440                         hci_reenable_advertisements_if_needed();
2441                     }
2442 #endif
2443 
2444                     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2445 
2446                     // restart timer
2447                     // btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2448                     // btstack_run_loop_add_timer(&conn->timeout);
2449 
2450                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2451 
2452                     hci_emit_nr_connections_changed();
2453                     break;
2454 
2455                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
2456                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
2457                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
2458                     conn = hci_connection_for_handle(handle);
2459                     if (!conn) break;
2460                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
2461                     break;
2462 
2463                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
2464                     // connection
2465                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
2466                     conn = hci_connection_for_handle(handle);
2467                     if (conn) {
2468                         // read arguments
2469                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
2470                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
2471                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
2472                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
2473 
2474                         // validate against current connection parameter range
2475                         le_connection_parameter_range_t existing_range;
2476                         gap_get_connection_parameter_range(&existing_range);
2477                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
2478                         if (update_parameter){
2479                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
2480                             conn->le_conn_interval_min = le_conn_interval_min;
2481                             conn->le_conn_interval_max = le_conn_interval_max;
2482                             conn->le_conn_latency = le_conn_latency;
2483                             conn->le_supervision_timeout = le_supervision_timeout;
2484                         } else {
2485                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_DENY;
2486                         }
2487                     }
2488                     break;
2489                 default:
2490                     break;
2491             }
2492             break;
2493 #endif
2494         case HCI_EVENT_VENDOR_SPECIFIC:
2495             // Vendor specific commands often create vendor specific event instead of num completed packets
2496             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
2497             switch (hci_stack->manufacturer){
2498                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
2499                     hci_stack->num_cmd_packets = 1;
2500                     break;
2501                 default:
2502                     break;
2503             }
2504             break;
2505         default:
2506             break;
2507     }
2508 
2509     // handle BT initialization
2510     if (hci_stack->state == HCI_STATE_INITIALIZING){
2511         hci_initializing_event_handler(packet, size);
2512     }
2513 
2514     // help with BT sleep
2515     if (hci_stack->state == HCI_STATE_FALLING_ASLEEP
2516         && hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE
2517         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)){
2518         hci_initializing_next_state();
2519     }
2520 
2521     // notify upper stack
2522 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
2523 
2524     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
2525     if (hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE){
2526         if (!packet[2]){
2527             handle = little_endian_read_16(packet, 3);
2528             hci_connection_t * aConn = hci_connection_for_handle(handle);
2529             if (aConn) {
2530                 uint8_t status = aConn->bonding_status;
2531                 uint16_t flags = aConn->bonding_flags;
2532                 bd_addr_t bd_address;
2533                 memcpy(&bd_address, aConn->address, 6);
2534                 hci_shutdown_connection(aConn);
2535                 // connection struct is gone, don't access anymore
2536                 if (flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
2537                     hci_emit_dedicated_bonding_result(bd_address, status);
2538                 }
2539             }
2540         }
2541     }
2542 
2543 	// execute main loop
2544 	hci_run();
2545 }
2546 
2547 #ifdef ENABLE_CLASSIC
2548 
2549 #define SCO_TX_AFTER_RX_MS 5
2550 
2551 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
2552 static void sco_schedule_tx(hci_connection_t * conn);
2553 
2554 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
2555     log_info("SCO TX Timeout");
2556     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
2557     hci_connection_t * conn = hci_connection_for_handle(con_handle);
2558     if (!conn) return;
2559 
2560     // schedule next
2561     sco_schedule_tx(conn);
2562     conn->sco_tx_count++;
2563 
2564     // trigger send
2565     conn->sco_tx_ready = 1;
2566     // extra packet if CVSD but SCO buffer is too short
2567     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && hci_stack->sco_data_packet_length < 123){
2568         conn->sco_tx_ready++;
2569     }
2570     hci_notify_if_sco_can_send_now();
2571 }
2572 
2573 static void sco_schedule_tx(hci_connection_t * conn){
2574     // find next time to send
2575     uint32_t now = btstack_run_loop_get_time_ms();
2576     uint32_t tx_ms;
2577     int time_delta_ms;
2578     while (1){
2579         // packet delay: count(rx) - count(tx)
2580         int packet_offset = (int8_t) (conn->sco_tx_count - conn->sco_rx_count);
2581         tx_ms = conn->sco_rx_ms + ((packet_offset * 15) >> 1) + SCO_TX_AFTER_RX_MS;
2582         time_delta_ms = (int) (tx_ms - now);
2583         if (time_delta_ms >= 3){
2584             break;
2585         }
2586         // skip packet
2587         conn->sco_tx_count++;
2588     }
2589     //
2590     log_info("SCO TX at %u in %u", (int) tx_ms, time_delta_ms);
2591     btstack_run_loop_set_timer(&conn->timeout, time_delta_ms);
2592     btstack_run_loop_set_timer_context(&conn->timeout, (void *) (uintptr_t) conn->con_handle);
2593     btstack_run_loop_set_timer_handler(&conn->timeout, &sco_tx_timeout_handler);
2594     btstack_run_loop_add_timer(&conn->timeout);
2595 }
2596 
2597 static void sco_handler(uint8_t * packet, uint16_t size){
2598     // lookup connection struct
2599     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
2600     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
2601     if (!conn) return;
2602 
2603     int notify_sco = 0;
2604 
2605     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
2606     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
2607         if (size == 83 && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
2608             packet[2] = 0x3c;
2609             memmove(&packet[3], &packet[23], 63);
2610             size = 63;
2611         }
2612     }
2613 
2614     if (hci_have_usb_transport()){
2615         // Nothing to do
2616     } else {
2617         // log_debug("sco flow %u, handle 0x%04x, packets sent %u, bytes send %u", hci_stack->synchronous_flow_control_enabled, (int) con_handle, conn->num_packets_sent, conn->num_sco_bytes_sent);
2618         if (hci_stack->synchronous_flow_control_enabled == 0){
2619             uint32_t now = btstack_run_loop_get_time_ms();
2620             if (conn->sco_rx_valid){
2621                 conn->sco_rx_count++;
2622                 // expected arrival timme
2623                 conn->sco_rx_ms += 7;
2624                 int delta = (int32_t) (now - conn->sco_rx_ms);
2625                 if (delta <= 0){
2626                     log_info("SCO NOW - EXP = %d, use +7 ms", delta);
2627                 } else {
2628                     conn->sco_rx_ms++;
2629                     log_info("SCO NOW > EXP = %d, use +8 ms", delta);
2630                 }
2631             } else {
2632                 // use first timestamp as is
2633                 conn->sco_rx_ms = now;
2634                 conn->sco_rx_valid = 1;
2635                 log_info("SCO first rx");
2636                 sco_schedule_tx(conn);
2637             }
2638         }
2639     }
2640     // deliver to app
2641     if (hci_stack->sco_packet_handler) {
2642         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
2643     }
2644 
2645     // notify app if it can send again
2646     if (notify_sco){
2647         hci_notify_if_sco_can_send_now();
2648     }
2649 
2650 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
2651     conn->num_packets_completed++;
2652     hci_stack->host_completed_packets = 1;
2653     hci_run();
2654 #endif
2655 }
2656 #endif
2657 
2658 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
2659     hci_dump_packet(packet_type, 1, packet, size);
2660     switch (packet_type) {
2661         case HCI_EVENT_PACKET:
2662             event_handler(packet, size);
2663             break;
2664         case HCI_ACL_DATA_PACKET:
2665             acl_handler(packet, size);
2666             break;
2667 #ifdef ENABLE_CLASSIC
2668         case HCI_SCO_DATA_PACKET:
2669             sco_handler(packet, size);
2670             break;
2671 #endif
2672         default:
2673             break;
2674     }
2675 }
2676 
2677 /**
2678  * @brief Add event packet handler.
2679  */
2680 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
2681     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
2682 }
2683 
2684 
2685 /** Register HCI packet handlers */
2686 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
2687     hci_stack->acl_packet_handler = handler;
2688 }
2689 
2690 #ifdef ENABLE_CLASSIC
2691 /**
2692  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
2693  */
2694 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
2695     hci_stack->sco_packet_handler = handler;
2696 }
2697 #endif
2698 
2699 static void hci_state_reset(void){
2700     // no connections yet
2701     hci_stack->connections = NULL;
2702 
2703     // keep discoverable/connectable as this has been requested by the client(s)
2704     // hci_stack->discoverable = 0;
2705     // hci_stack->connectable = 0;
2706     // hci_stack->bondable = 1;
2707     // hci_stack->own_addr_type = 0;
2708 
2709     // buffer is free
2710     hci_stack->hci_packet_buffer_reserved = 0;
2711 
2712     // no pending cmds
2713     hci_stack->decline_reason = 0;
2714     hci_stack->new_scan_enable_value = 0xff;
2715 
2716     // LE
2717 #ifdef ENABLE_BLE
2718     memset(hci_stack->le_random_address, 0, 6);
2719     hci_stack->le_random_address_set = 0;
2720 #endif
2721 #ifdef ENABLE_LE_CENTRAL
2722     hci_stack->le_scanning_active  = 0;
2723     hci_stack->le_scan_type = 0xff;
2724     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2725     hci_stack->le_whitelist = 0;
2726     hci_stack->le_whitelist_capacity = 0;
2727 #endif
2728 }
2729 
2730 #ifdef ENABLE_CLASSIC
2731 /**
2732  * @brief Configure Bluetooth hardware control. Has to be called before power on.
2733  */
2734 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
2735     // store and open remote device db
2736     hci_stack->link_key_db = link_key_db;
2737     if (hci_stack->link_key_db) {
2738         hci_stack->link_key_db->open();
2739     }
2740 }
2741 #endif
2742 
2743 void hci_init(const hci_transport_t *transport, const void *config){
2744 
2745 #ifdef HAVE_MALLOC
2746     if (!hci_stack) {
2747         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
2748     }
2749 #else
2750     hci_stack = &hci_stack_static;
2751 #endif
2752     memset(hci_stack, 0, sizeof(hci_stack_t));
2753 
2754     // reference to use transport layer implementation
2755     hci_stack->hci_transport = transport;
2756 
2757     // reference to used config
2758     hci_stack->config = config;
2759 
2760     // setup pointer for outgoing packet buffer
2761     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
2762 
2763     // max acl payload size defined in config.h
2764     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
2765 
2766     // register packet handlers with transport
2767     transport->register_packet_handler(&packet_handler);
2768 
2769     hci_stack->state = HCI_STATE_OFF;
2770 
2771     // class of device
2772     hci_stack->class_of_device = 0x007a020c; // Smartphone
2773 
2774     // bondable by default
2775     hci_stack->bondable = 1;
2776 
2777 #ifdef ENABLE_CLASSIC
2778     // classic name
2779     hci_stack->local_name = default_classic_name;
2780 
2781     // Master slave policy
2782     hci_stack->master_slave_policy = 1;
2783 #endif
2784 
2785     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
2786     hci_stack->ssp_enable = 1;
2787     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
2788     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
2789     hci_stack->ssp_auto_accept = 1;
2790 
2791     // voice setting - signed 16 bit pcm data with CVSD over the air
2792     hci_stack->sco_voice_setting = 0x60;
2793 
2794 #ifdef ENABLE_LE_CENTRAL
2795     // connection parameter to use for outgoing connections
2796     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
2797     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
2798     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
2799     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
2800     hci_stack->le_connection_latency      = 4;         // 4
2801     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
2802     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
2803     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
2804 #endif
2805 
2806 #ifdef ENABLE_LE_PERIPHERAL
2807     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
2808 #endif
2809 
2810     // connection parameter range used to answer connection parameter update requests in l2cap
2811     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
2812     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
2813     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
2814     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
2815     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
2816     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
2817 
2818     hci_state_reset();
2819 }
2820 
2821 /**
2822  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
2823  */
2824 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
2825     hci_stack->chipset = chipset_driver;
2826 
2827     // reset chipset driver - init is also called on power_up
2828     if (hci_stack->chipset && hci_stack->chipset->init){
2829         hci_stack->chipset->init(hci_stack->config);
2830     }
2831 }
2832 
2833 /**
2834  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
2835  */
2836 void hci_set_control(const btstack_control_t *hardware_control){
2837     // references to used control implementation
2838     hci_stack->control = hardware_control;
2839     // init with transport config
2840     hardware_control->init(hci_stack->config);
2841 }
2842 
2843 void hci_close(void){
2844     // close remote device db
2845     if (hci_stack->link_key_db) {
2846         hci_stack->link_key_db->close();
2847     }
2848 
2849     btstack_linked_list_iterator_t lit;
2850     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
2851     while (btstack_linked_list_iterator_has_next(&lit)){
2852         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
2853         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
2854         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
2855         hci_shutdown_connection(connection);
2856     }
2857 
2858     hci_power_control(HCI_POWER_OFF);
2859 
2860 #ifdef HAVE_MALLOC
2861     free(hci_stack);
2862 #endif
2863     hci_stack = NULL;
2864 }
2865 
2866 #ifdef ENABLE_CLASSIC
2867 void gap_set_class_of_device(uint32_t class_of_device){
2868     hci_stack->class_of_device = class_of_device;
2869 }
2870 
2871 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
2872     hci_stack->default_link_policy_settings = default_link_policy_settings;
2873 }
2874 
2875 void hci_disable_l2cap_timeout_check(void){
2876     disable_l2cap_timeouts = 1;
2877 }
2878 #endif
2879 
2880 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
2881 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
2882 void hci_set_bd_addr(bd_addr_t addr){
2883     memcpy(hci_stack->custom_bd_addr, addr, 6);
2884     hci_stack->custom_bd_addr_set = 1;
2885 }
2886 #endif
2887 
2888 // State-Module-Driver overview
2889 // state                    module  low-level
2890 // HCI_STATE_OFF             off      close
2891 // HCI_STATE_INITIALIZING,   on       open
2892 // HCI_STATE_WORKING,        on       open
2893 // HCI_STATE_HALTING,        on       open
2894 // HCI_STATE_SLEEPING,    off/sleep   close
2895 // HCI_STATE_FALLING_ASLEEP  on       open
2896 
2897 static int hci_power_control_on(void){
2898 
2899     // power on
2900     int err = 0;
2901     if (hci_stack->control && hci_stack->control->on){
2902         err = (*hci_stack->control->on)();
2903     }
2904     if (err){
2905         log_error( "POWER_ON failed");
2906         hci_emit_hci_open_failed();
2907         return err;
2908     }
2909 
2910     // int chipset driver
2911     if (hci_stack->chipset && hci_stack->chipset->init){
2912         hci_stack->chipset->init(hci_stack->config);
2913     }
2914 
2915     // init transport
2916     if (hci_stack->hci_transport->init){
2917         hci_stack->hci_transport->init(hci_stack->config);
2918     }
2919 
2920     // open transport
2921     err = hci_stack->hci_transport->open();
2922     if (err){
2923         log_error( "HCI_INIT failed, turning Bluetooth off again");
2924         if (hci_stack->control && hci_stack->control->off){
2925             (*hci_stack->control->off)();
2926         }
2927         hci_emit_hci_open_failed();
2928         return err;
2929     }
2930     return 0;
2931 }
2932 
2933 static void hci_power_control_off(void){
2934 
2935     log_info("hci_power_control_off");
2936 
2937     // close low-level device
2938     hci_stack->hci_transport->close();
2939 
2940     log_info("hci_power_control_off - hci_transport closed");
2941 
2942     // power off
2943     if (hci_stack->control && hci_stack->control->off){
2944         (*hci_stack->control->off)();
2945     }
2946 
2947     log_info("hci_power_control_off - control closed");
2948 
2949     hci_stack->state = HCI_STATE_OFF;
2950 }
2951 
2952 static void hci_power_control_sleep(void){
2953 
2954     log_info("hci_power_control_sleep");
2955 
2956 #if 0
2957     // don't close serial port during sleep
2958 
2959     // close low-level device
2960     hci_stack->hci_transport->close(hci_stack->config);
2961 #endif
2962 
2963     // sleep mode
2964     if (hci_stack->control && hci_stack->control->sleep){
2965         (*hci_stack->control->sleep)();
2966     }
2967 
2968     hci_stack->state = HCI_STATE_SLEEPING;
2969 }
2970 
2971 static int hci_power_control_wake(void){
2972 
2973     log_info("hci_power_control_wake");
2974 
2975     // wake on
2976     if (hci_stack->control && hci_stack->control->wake){
2977         (*hci_stack->control->wake)();
2978     }
2979 
2980 #if 0
2981     // open low-level device
2982     int err = hci_stack->hci_transport->open(hci_stack->config);
2983     if (err){
2984         log_error( "HCI_INIT failed, turning Bluetooth off again");
2985         if (hci_stack->control && hci_stack->control->off){
2986             (*hci_stack->control->off)();
2987         }
2988         hci_emit_hci_open_failed();
2989         return err;
2990     }
2991 #endif
2992 
2993     return 0;
2994 }
2995 
2996 static void hci_power_transition_to_initializing(void){
2997     // set up state machine
2998     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
2999     hci_stack->hci_packet_buffer_reserved = 0;
3000     hci_stack->state = HCI_STATE_INITIALIZING;
3001     hci_stack->substate = HCI_INIT_SEND_RESET;
3002 }
3003 
3004 int hci_power_control(HCI_POWER_MODE power_mode){
3005 
3006     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
3007 
3008     int err = 0;
3009     switch (hci_stack->state){
3010 
3011         case HCI_STATE_OFF:
3012             switch (power_mode){
3013                 case HCI_POWER_ON:
3014                     err = hci_power_control_on();
3015                     if (err) {
3016                         log_error("hci_power_control_on() error %d", err);
3017                         return err;
3018                     }
3019                     hci_power_transition_to_initializing();
3020                     break;
3021                 case HCI_POWER_OFF:
3022                     // do nothing
3023                     break;
3024                 case HCI_POWER_SLEEP:
3025                     // do nothing (with SLEEP == OFF)
3026                     break;
3027             }
3028             break;
3029 
3030         case HCI_STATE_INITIALIZING:
3031             switch (power_mode){
3032                 case HCI_POWER_ON:
3033                     // do nothing
3034                     break;
3035                 case HCI_POWER_OFF:
3036                     // no connections yet, just turn it off
3037                     hci_power_control_off();
3038                     break;
3039                 case HCI_POWER_SLEEP:
3040                     // no connections yet, just turn it off
3041                     hci_power_control_sleep();
3042                     break;
3043             }
3044             break;
3045 
3046         case HCI_STATE_WORKING:
3047             switch (power_mode){
3048                 case HCI_POWER_ON:
3049                     // do nothing
3050                     break;
3051                 case HCI_POWER_OFF:
3052                     // see hci_run
3053                     hci_stack->state = HCI_STATE_HALTING;
3054                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3055                     break;
3056                 case HCI_POWER_SLEEP:
3057                     // see hci_run
3058                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3059                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3060                     break;
3061             }
3062             break;
3063 
3064         case HCI_STATE_HALTING:
3065             switch (power_mode){
3066                 case HCI_POWER_ON:
3067                     hci_power_transition_to_initializing();
3068                     break;
3069                 case HCI_POWER_OFF:
3070                     // do nothing
3071                     break;
3072                 case HCI_POWER_SLEEP:
3073                     // see hci_run
3074                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3075                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3076                     break;
3077             }
3078             break;
3079 
3080         case HCI_STATE_FALLING_ASLEEP:
3081             switch (power_mode){
3082                 case HCI_POWER_ON:
3083 
3084 #ifdef HAVE_PLATFORM_IPHONE_OS
3085                     // nothing to do, if H4 supports power management
3086                     if (btstack_control_iphone_power_management_enabled()){
3087                         hci_stack->state = HCI_STATE_INITIALIZING;
3088                         hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;   // init after sleep
3089                         break;
3090                     }
3091 #endif
3092                     hci_power_transition_to_initializing();
3093                     break;
3094                 case HCI_POWER_OFF:
3095                     // see hci_run
3096                     hci_stack->state = HCI_STATE_HALTING;
3097                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3098                     break;
3099                 case HCI_POWER_SLEEP:
3100                     // do nothing
3101                     break;
3102             }
3103             break;
3104 
3105         case HCI_STATE_SLEEPING:
3106             switch (power_mode){
3107                 case HCI_POWER_ON:
3108 
3109 #ifdef HAVE_PLATFORM_IPHONE_OS
3110                     // nothing to do, if H4 supports power management
3111                     if (btstack_control_iphone_power_management_enabled()){
3112                         hci_stack->state = HCI_STATE_INITIALIZING;
3113                         hci_stack->substate = HCI_INIT_AFTER_SLEEP;
3114                         hci_update_scan_enable();
3115                         break;
3116                     }
3117 #endif
3118                     err = hci_power_control_wake();
3119                     if (err) return err;
3120                     hci_power_transition_to_initializing();
3121                     break;
3122                 case HCI_POWER_OFF:
3123                     hci_stack->state = HCI_STATE_HALTING;
3124                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3125                     break;
3126                 case HCI_POWER_SLEEP:
3127                     // do nothing
3128                     break;
3129             }
3130             break;
3131     }
3132 
3133     // create internal event
3134 	hci_emit_state();
3135 
3136 	// trigger next/first action
3137 	hci_run();
3138 
3139     return 0;
3140 }
3141 
3142 
3143 #ifdef ENABLE_CLASSIC
3144 
3145 static void hci_update_scan_enable(void){
3146     // 2 = page scan, 1 = inq scan
3147     hci_stack->new_scan_enable_value  = hci_stack->connectable << 1 | hci_stack->discoverable;
3148     hci_run();
3149 }
3150 
3151 void gap_discoverable_control(uint8_t enable){
3152     if (enable) enable = 1; // normalize argument
3153 
3154     if (hci_stack->discoverable == enable){
3155         hci_emit_discoverable_enabled(hci_stack->discoverable);
3156         return;
3157     }
3158 
3159     hci_stack->discoverable = enable;
3160     hci_update_scan_enable();
3161 }
3162 
3163 void gap_connectable_control(uint8_t enable){
3164     if (enable) enable = 1; // normalize argument
3165 
3166     // don't emit event
3167     if (hci_stack->connectable == enable) return;
3168 
3169     hci_stack->connectable = enable;
3170     hci_update_scan_enable();
3171 }
3172 #endif
3173 
3174 void gap_local_bd_addr(bd_addr_t address_buffer){
3175     memcpy(address_buffer, hci_stack->local_bd_addr, 6);
3176 }
3177 
3178 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3179 static void hci_host_num_completed_packets(void){
3180 
3181     // create packet manually as arrays are not supported and num_commands should not get reduced
3182     hci_reserve_packet_buffer();
3183     uint8_t * packet = hci_get_outgoing_packet_buffer();
3184 
3185     uint16_t size = 0;
3186     uint16_t num_handles = 0;
3187     packet[size++] = 0x35;
3188     packet[size++] = 0x0c;
3189     size++;  // skip param len
3190     size++;  // skip num handles
3191 
3192     // add { handle, packets } entries
3193     btstack_linked_item_t * it;
3194     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
3195         hci_connection_t * connection = (hci_connection_t *) it;
3196         if (connection->num_packets_completed){
3197             little_endian_store_16(packet, size, connection->con_handle);
3198             size += 2;
3199             little_endian_store_16(packet, size, connection->num_packets_completed);
3200             size += 2;
3201             //
3202             num_handles++;
3203             connection->num_packets_completed = 0;
3204         }
3205     }
3206 
3207     packet[2] = size - 3;
3208     packet[3] = num_handles;
3209 
3210     hci_stack->host_completed_packets = 0;
3211 
3212     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
3213     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
3214 
3215     // release packet buffer for synchronous transport implementations
3216     if (hci_transport_synchronous()){
3217         hci_release_packet_buffer();
3218         hci_emit_transport_packet_sent();
3219     }
3220 }
3221 #endif
3222 
3223 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
3224     UNUSED(ds);
3225     hci_stack->substate = HCI_HALTING_CLOSE;
3226     // allow packet handlers to defer final shutdown
3227     hci_emit_state();
3228     hci_run();
3229 }
3230 
3231 static void hci_run(void){
3232 
3233     // log_info("hci_run: entered");
3234     btstack_linked_item_t * it;
3235 
3236     // send continuation fragments first, as they block the prepared packet buffer
3237     if (hci_stack->acl_fragmentation_total_size > 0) {
3238         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
3239         hci_connection_t *connection = hci_connection_for_handle(con_handle);
3240         if (connection) {
3241             if (hci_can_send_prepared_acl_packet_now(con_handle)){
3242                 hci_send_acl_packet_fragments(connection);
3243                 return;
3244             }
3245         } else {
3246             // connection gone -> discard further fragments
3247             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
3248             hci_stack->acl_fragmentation_total_size = 0;
3249             hci_stack->acl_fragmentation_pos = 0;
3250         }
3251     }
3252 
3253 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3254     // send host num completed packets next as they don't require num_cmd_packets > 0
3255     if (!hci_can_send_comand_packet_transport()) return;
3256     if (hci_stack->host_completed_packets){
3257         hci_host_num_completed_packets();
3258         return;
3259     }
3260 #endif
3261 
3262     if (!hci_can_send_command_packet_now()) return;
3263 
3264     // global/non-connection oriented commands
3265 
3266 #ifdef ENABLE_CLASSIC
3267     // decline incoming connections
3268     if (hci_stack->decline_reason){
3269         uint8_t reason = hci_stack->decline_reason;
3270         hci_stack->decline_reason = 0;
3271         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
3272         return;
3273     }
3274     // send scan enable
3275     if (hci_stack->state == HCI_STATE_WORKING && hci_stack->new_scan_enable_value != 0xff && hci_classic_supported()){
3276         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
3277         hci_stack->new_scan_enable_value = 0xff;
3278         return;
3279     }
3280     // start/stop inquiry
3281     if (hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN && hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX){
3282         uint8_t duration = hci_stack->inquiry_state;
3283         hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
3284         hci_send_cmd(&hci_inquiry, GAP_IAC_GENERAL_INQUIRY, duration, 0);
3285         return;
3286     }
3287     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
3288         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
3289         hci_send_cmd(&hci_inquiry_cancel);
3290         return;
3291     }
3292     // remote name request
3293     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
3294         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
3295         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
3296             hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
3297         return;
3298     }
3299     // pairing
3300     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
3301         uint8_t state = hci_stack->gap_pairing_state;
3302         hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
3303         switch (state){
3304             case GAP_PAIRING_STATE_SEND_PIN:
3305                 hci_send_cmd(&hci_pin_code_request_reply, hci_stack->gap_pairing_addr, strlen(hci_stack->gap_pairing_input.gap_pairing_pin), hci_stack->gap_pairing_input.gap_pairing_pin);
3306                 break;
3307             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
3308                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
3309                 break;
3310             case GAP_PAIRING_STATE_SEND_PASSKEY:
3311                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
3312                 break;
3313             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
3314                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
3315                 break;
3316             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
3317                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
3318                 break;
3319             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
3320                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
3321                 break;
3322             default:
3323                 break;
3324         }
3325         return;
3326     }
3327 #endif
3328 
3329 #ifdef ENABLE_BLE
3330     // advertisements, active scanning, and creating connections requires randaom address to be set if using private address
3331     if ((hci_stack->state == HCI_STATE_WORKING)
3332     && (hci_stack->le_own_addr_type == BD_ADDR_TYPE_LE_PUBLIC || hci_stack->le_random_address_set)){
3333 
3334 #ifdef ENABLE_LE_CENTRAL
3335         // handle le scan
3336         if ((hci_stack->le_scanning_enabled != hci_stack->le_scanning_active)){
3337             hci_stack->le_scanning_active = hci_stack->le_scanning_enabled;
3338             hci_send_cmd(&hci_le_set_scan_enable, hci_stack->le_scanning_enabled, 0);
3339             return;
3340         }
3341         if (hci_stack->le_scan_type != 0xff){
3342             // defaults: active scanning, accept all advertisement packets
3343             int scan_type = hci_stack->le_scan_type;
3344             hci_stack->le_scan_type = 0xff;
3345             hci_send_cmd(&hci_le_set_scan_parameters, scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window, hci_stack->le_own_addr_type, 0);
3346             return;
3347         }
3348 #endif
3349 #ifdef ENABLE_LE_PERIPHERAL
3350         // le advertisement control
3351         if (hci_stack->le_advertisements_todo){
3352             log_info("hci_run: gap_le: adv todo: %x", hci_stack->le_advertisements_todo );
3353         }
3354         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_DISABLE){
3355             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_DISABLE;
3356             hci_send_cmd(&hci_le_set_advertise_enable, 0);
3357             return;
3358         }
3359         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
3360             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3361             hci_send_cmd(&hci_le_set_advertising_parameters,
3362                  hci_stack->le_advertisements_interval_min,
3363                  hci_stack->le_advertisements_interval_max,
3364                  hci_stack->le_advertisements_type,
3365                  hci_stack->le_own_addr_type,
3366                  hci_stack->le_advertisements_direct_address_type,
3367                  hci_stack->le_advertisements_direct_address,
3368                  hci_stack->le_advertisements_channel_map,
3369                  hci_stack->le_advertisements_filter_policy);
3370             return;
3371         }
3372         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
3373             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3374             uint8_t adv_data_clean[31];
3375             memset(adv_data_clean, 0, sizeof(adv_data_clean));
3376             memcpy(adv_data_clean, hci_stack->le_advertisements_data, hci_stack->le_advertisements_data_len);
3377             hci_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len);
3378             hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
3379             return;
3380         }
3381         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
3382             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
3383             uint8_t scan_data_clean[31];
3384             memset(scan_data_clean, 0, sizeof(scan_data_clean));
3385             memcpy(scan_data_clean, hci_stack->le_scan_response_data, hci_stack->le_scan_response_data_len);
3386             hci_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len);
3387             hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, hci_stack->le_scan_response_data);
3388             return;
3389         }
3390         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_ENABLE){
3391             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_ENABLE;
3392             hci_send_cmd(&hci_le_set_advertise_enable, 1);
3393             return;
3394         }
3395 #endif
3396 
3397 #ifdef ENABLE_LE_CENTRAL
3398         //
3399         // LE Whitelist Management
3400         //
3401 
3402         // check if whitelist needs modification
3403         btstack_linked_list_iterator_t lit;
3404         int modification_pending = 0;
3405         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3406         while (btstack_linked_list_iterator_has_next(&lit)){
3407             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3408             if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
3409                 modification_pending = 1;
3410                 break;
3411             }
3412         }
3413 
3414         if (modification_pending){
3415             // stop connnecting if modification pending
3416             if (hci_stack->le_connecting_state != LE_CONNECTING_IDLE){
3417                 hci_send_cmd(&hci_le_create_connection_cancel);
3418                 return;
3419             }
3420 
3421             // add/remove entries
3422             btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3423             while (btstack_linked_list_iterator_has_next(&lit)){
3424                 whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3425                 if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
3426                     entry->state = LE_WHITELIST_ON_CONTROLLER;
3427                     hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
3428                     return;
3429 
3430                 }
3431                 if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
3432                     bd_addr_t address;
3433                     bd_addr_type_t address_type = entry->address_type;
3434                     memcpy(address, entry->address, 6);
3435                     btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
3436                     btstack_memory_whitelist_entry_free(entry);
3437                     hci_send_cmd(&hci_le_remove_device_from_white_list, address_type, address);
3438                     return;
3439                 }
3440             }
3441         }
3442 
3443         // start connecting
3444         if ( hci_stack->le_connecting_state == LE_CONNECTING_IDLE &&
3445             !btstack_linked_list_empty(&hci_stack->le_whitelist)){
3446             bd_addr_t null_addr;
3447             memset(null_addr, 0, 6);
3448             hci_send_cmd(&hci_le_create_connection,
3449                 hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
3450                 hci_stack->le_connection_scan_window,    // scan interval: 30 ms
3451                  1,         // use whitelist
3452                  0,         // peer address type
3453                  null_addr, // peer bd addr
3454                  hci_stack->le_own_addr_type, // our addr type:
3455                  hci_stack->le_connection_interval_min,    // conn interval min
3456                  hci_stack->le_connection_interval_max,    // conn interval max
3457                  hci_stack->le_connection_latency,         // conn latency
3458                  hci_stack->le_supervision_timeout,        // conn latency
3459                  hci_stack->le_minimum_ce_length,          // min ce length
3460                  hci_stack->le_maximum_ce_length           // max ce length
3461                 );
3462             return;
3463         }
3464 #endif
3465     }
3466 #endif
3467 
3468     // send pending HCI commands
3469     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
3470         hci_connection_t * connection = (hci_connection_t *) it;
3471 
3472         switch(connection->state){
3473             case SEND_CREATE_CONNECTION:
3474                 switch(connection->address_type){
3475 #ifdef ENABLE_CLASSIC
3476                     case BD_ADDR_TYPE_CLASSIC:
3477                         log_info("sending hci_create_connection");
3478                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, 1);
3479                         break;
3480 #endif
3481                     default:
3482 #ifdef ENABLE_BLE
3483 #ifdef ENABLE_LE_CENTRAL
3484                         // track outgoing connection
3485                         hci_stack->outgoing_addr_type = connection->address_type;
3486                         memcpy(hci_stack->outgoing_addr, connection->address, 6);
3487                         log_info("sending hci_le_create_connection");
3488                         hci_send_cmd(&hci_le_create_connection,
3489                              hci_stack->le_connection_scan_interval,    // conn scan interval
3490                              hci_stack->le_connection_scan_window,      // conn scan windows
3491                              0,         // don't use whitelist
3492                              connection->address_type, // peer address type
3493                              connection->address,      // peer bd addr
3494                              hci_stack->le_own_addr_type, // our addr type:
3495                              hci_stack->le_connection_interval_min,    // conn interval min
3496                              hci_stack->le_connection_interval_max,    // conn interval max
3497                              hci_stack->le_connection_latency,         // conn latency
3498                              hci_stack->le_supervision_timeout,        // conn latency
3499                              hci_stack->le_minimum_ce_length,          // min ce length
3500                              hci_stack->le_maximum_ce_length          // max ce length
3501                              );
3502                         connection->state = SENT_CREATE_CONNECTION;
3503 #endif
3504 #endif
3505                         break;
3506                 }
3507                 return;
3508 
3509 #ifdef ENABLE_CLASSIC
3510             case RECEIVED_CONNECTION_REQUEST:
3511                 connection->role  = HCI_ROLE_SLAVE;
3512                 if (connection->address_type == BD_ADDR_TYPE_CLASSIC){
3513                     log_info("sending hci_accept_connection_request, remote eSCO %u", connection->remote_supported_feature_eSCO);
3514                     connection->state = ACCEPTED_CONNECTION_REQUEST;
3515                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
3516                 }
3517                 return;
3518 #endif
3519 
3520 #ifdef ENABLE_BLE
3521 #ifdef ENABLE_LE_CENTRAL
3522             case SEND_CANCEL_CONNECTION:
3523                 connection->state = SENT_CANCEL_CONNECTION;
3524                 hci_send_cmd(&hci_le_create_connection_cancel);
3525                 return;
3526 #endif
3527 #endif
3528             case SEND_DISCONNECT:
3529                 connection->state = SENT_DISCONNECT;
3530                 hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13); // remote closed connection
3531                 return;
3532 
3533             default:
3534                 break;
3535         }
3536 
3537         // no further commands if connection is about to get shut down
3538         if (connection->state == SENT_DISCONNECT) continue;
3539 
3540 #ifdef ENABLE_CLASSIC
3541         if (connection->authentication_flags & HANDLE_LINK_KEY_REQUEST){
3542             log_info("responding to link key request");
3543             connectionClearAuthenticationFlags(connection, HANDLE_LINK_KEY_REQUEST);
3544             link_key_t link_key;
3545             link_key_type_t link_key_type;
3546             if ( hci_stack->link_key_db
3547               && hci_stack->link_key_db->get_link_key(connection->address, link_key, &link_key_type)
3548               && gap_security_level_for_link_key_type(link_key_type) >= connection->requested_security_level){
3549                connection->link_key_type = link_key_type;
3550                hci_send_cmd(&hci_link_key_request_reply, connection->address, &link_key);
3551             } else {
3552                hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
3553             }
3554             return;
3555         }
3556 
3557         if (connection->authentication_flags & DENY_PIN_CODE_REQUEST){
3558             log_info("denying to pin request");
3559             connectionClearAuthenticationFlags(connection, DENY_PIN_CODE_REQUEST);
3560             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
3561             return;
3562         }
3563 
3564         if (connection->authentication_flags & SEND_IO_CAPABILITIES_REPLY){
3565             connectionClearAuthenticationFlags(connection, SEND_IO_CAPABILITIES_REPLY);
3566             log_info("IO Capability Request received, stack bondable %u, io cap %u", hci_stack->bondable, hci_stack->ssp_io_capability);
3567             if (hci_stack->bondable && (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN)){
3568                 // tweak authentication requirements
3569                 uint8_t authreq = hci_stack->ssp_authentication_requirement;
3570                 if (connection->bonding_flags & BONDING_DEDICATED){
3571                     authreq = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
3572                 }
3573                 if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
3574                     authreq |= 1;
3575                 }
3576                 hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, NULL, authreq);
3577             } else {
3578                 hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
3579             }
3580             return;
3581         }
3582 
3583         if (connection->authentication_flags & SEND_USER_CONFIRM_REPLY){
3584             connectionClearAuthenticationFlags(connection, SEND_USER_CONFIRM_REPLY);
3585             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
3586             return;
3587         }
3588 
3589         if (connection->authentication_flags & SEND_USER_PASSKEY_REPLY){
3590             connectionClearAuthenticationFlags(connection, SEND_USER_PASSKEY_REPLY);
3591             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
3592             return;
3593         }
3594 
3595         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES){
3596             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES;
3597             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
3598             return;
3599         }
3600 
3601         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
3602             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
3603             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
3604             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // authentication done
3605             return;
3606         }
3607 
3608         if (connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST){
3609             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
3610             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
3611             return;
3612         }
3613 
3614         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
3615             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
3616             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
3617             return;
3618         }
3619 #endif
3620 
3621         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
3622             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
3623             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x0005);  // authentication failure
3624             return;
3625         }
3626 
3627 #ifdef ENABLE_CLASSIC
3628         uint16_t sniff_min_interval;
3629         switch (connection->sniff_min_interval){
3630             case 0:
3631                 break;
3632             case 0xffff:
3633                 connection->sniff_min_interval = 0;
3634                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
3635                 return;
3636             default:
3637                 sniff_min_interval = connection->sniff_min_interval;
3638                 connection->sniff_min_interval = 0;
3639                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
3640                 return;
3641         }
3642 #endif
3643 
3644 #ifdef ENABLE_BLE
3645         switch (connection->le_con_parameter_update_state){
3646             // response to L2CAP CON PARAMETER UPDATE REQUEST
3647             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
3648                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
3649                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
3650                     connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
3651                     0x0000, 0xffff);
3652                 return;
3653             case CON_PARAMETER_UPDATE_REPLY:
3654                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
3655                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
3656                     connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
3657                     0x0000, 0xffff);
3658                 return;
3659             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
3660                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
3661                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
3662                 return;
3663             default:
3664                 break;
3665         }
3666         if (connection->le_phy_update_all_phys != 0xff){
3667             uint8_t all_phys = connection->le_phy_update_all_phys;
3668             connection->le_phy_update_all_phys = 0xff;
3669             hci_send_cmd(&hci_le_set_phy, connection->con_handle, all_phys, connection->le_phy_update_tx_phys, connection->le_phy_update_rx_phys, connection->le_phy_update_phy_options);
3670             return;
3671         }
3672 #endif
3673     }
3674 
3675     hci_connection_t * connection;
3676     switch (hci_stack->state){
3677         case HCI_STATE_INITIALIZING:
3678             hci_initializing_run();
3679             break;
3680 
3681         case HCI_STATE_HALTING:
3682 
3683             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
3684             switch (hci_stack->substate){
3685                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
3686                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
3687 
3688 #ifdef ENABLE_BLE
3689 #ifdef ENABLE_LE_CENTRAL
3690                     // free whitelist entries
3691                     {
3692                         btstack_linked_list_iterator_t lit;
3693                         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3694                         while (btstack_linked_list_iterator_has_next(&lit)){
3695                             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3696                             btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
3697                             btstack_memory_whitelist_entry_free(entry);
3698                         }
3699                     }
3700 #endif
3701 #endif
3702                     // close all open connections
3703                     connection =  (hci_connection_t *) hci_stack->connections;
3704                     if (connection){
3705                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
3706                         if (!hci_can_send_command_packet_now()) return;
3707 
3708                         // check state
3709                         if (connection->state == SENT_DISCONNECT) return;
3710                         connection->state = SENT_DISCONNECT;
3711 
3712                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
3713 
3714                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
3715                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
3716 
3717                         // ... which would be ignored anyway as we shutdown (free) the connection now
3718                         hci_shutdown_connection(connection);
3719 
3720                         // finally, send the disconnect command
3721                         hci_send_cmd(&hci_disconnect, con_handle, 0x13);  // remote closed connection
3722                         return;
3723                     }
3724 
3725                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
3726                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
3727                         log_info("HCI_STATE_HALTING: wait 50 ms");
3728                         hci_stack->substate = HCI_HALTING_W4_TIMER;
3729                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
3730                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
3731                         btstack_run_loop_add_timer(&hci_stack->timeout);
3732                         break;
3733                     }
3734 
3735                     /* explicit fall-through */
3736 
3737                 case HCI_HALTING_CLOSE:
3738                     log_info("HCI_STATE_HALTING, calling off");
3739 
3740                     // switch mode
3741                     hci_power_control_off();
3742 
3743                     log_info("HCI_STATE_HALTING, emitting state");
3744                     hci_emit_state();
3745                     log_info("HCI_STATE_HALTING, done");
3746                     break;
3747 
3748                 case HCI_HALTING_W4_TIMER:
3749                     // keep waiting
3750 
3751                     break;
3752                 default:
3753                     break;
3754             }
3755 
3756             break;
3757 
3758         case HCI_STATE_FALLING_ASLEEP:
3759             switch(hci_stack->substate) {
3760                 case HCI_FALLING_ASLEEP_DISCONNECT:
3761                     log_info("HCI_STATE_FALLING_ASLEEP");
3762                     // close all open connections
3763                     connection =  (hci_connection_t *) hci_stack->connections;
3764 
3765 #ifdef HAVE_PLATFORM_IPHONE_OS
3766                     // don't close connections, if H4 supports power management
3767                     if (btstack_control_iphone_power_management_enabled()){
3768                         connection = NULL;
3769                     }
3770 #endif
3771                     if (connection){
3772 
3773                         // send disconnect
3774                         if (!hci_can_send_command_packet_now()) return;
3775 
3776                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
3777                         hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // remote closed connection
3778 
3779                         // send disconnected event right away - causes higher layer connections to get closed, too.
3780                         hci_shutdown_connection(connection);
3781                         return;
3782                     }
3783 
3784                     if (hci_classic_supported()){
3785                         // disable page and inquiry scan
3786                         if (!hci_can_send_command_packet_now()) return;
3787 
3788                         log_info("HCI_STATE_HALTING, disabling inq scans");
3789                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
3790 
3791                         // continue in next sub state
3792                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
3793                         break;
3794                     }
3795                     // no break - fall through for ble-only chips
3796 
3797                 case HCI_FALLING_ASLEEP_COMPLETE:
3798                     log_info("HCI_STATE_HALTING, calling sleep");
3799 #ifdef HAVE_PLATFORM_IPHONE_OS
3800                     // don't actually go to sleep, if H4 supports power management
3801                     if (btstack_control_iphone_power_management_enabled()){
3802                         // SLEEP MODE reached
3803                         hci_stack->state = HCI_STATE_SLEEPING;
3804                         hci_emit_state();
3805                         break;
3806                     }
3807 #endif
3808                     // switch mode
3809                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
3810                     hci_emit_state();
3811                     break;
3812 
3813                 default:
3814                     break;
3815             }
3816             break;
3817 
3818         default:
3819             break;
3820     }
3821 }
3822 
3823 int hci_send_cmd_packet(uint8_t *packet, int size){
3824     // house-keeping
3825 
3826     if (IS_COMMAND(packet, hci_write_loopback_mode)){
3827         hci_stack->loopback_mode = packet[3];
3828     }
3829 
3830 #ifdef ENABLE_CLASSIC
3831     bd_addr_t addr;
3832     hci_connection_t * conn;
3833 
3834     // create_connection?
3835     if (IS_COMMAND(packet, hci_create_connection)){
3836         reverse_bd_addr(&packet[3], addr);
3837         log_info("Create_connection to %s", bd_addr_to_str(addr));
3838 
3839         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
3840         if (!conn){
3841             conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
3842             if (!conn){
3843                 // notify client that alloc failed
3844                 hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
3845                 return -1; // packet not sent to controller
3846             }
3847             conn->state = SEND_CREATE_CONNECTION;
3848         }
3849         log_info("conn state %u", conn->state);
3850         switch (conn->state){
3851             // if connection active exists
3852             case OPEN:
3853                 // and OPEN, emit connection complete command
3854                 hci_emit_connection_complete(addr, conn->con_handle, 0);
3855                 return -1; // packet not sent to controller
3856             case SEND_CREATE_CONNECTION:
3857                 // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
3858                 break;
3859             default:
3860                 // otherwise, just ignore as it is already in the open process
3861                 return -1; // packet not sent to controller
3862         }
3863         conn->state = SENT_CREATE_CONNECTION;
3864 
3865         // track outgoing connection
3866         hci_stack->outgoing_addr_type = BD_ADDR_TYPE_CLASSIC;
3867         memcpy(hci_stack->outgoing_addr, addr, 6);
3868     }
3869 
3870     if (IS_COMMAND(packet, hci_link_key_request_reply)){
3871         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
3872     }
3873     if (IS_COMMAND(packet, hci_link_key_request_negative_reply)){
3874         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
3875     }
3876 
3877     if (IS_COMMAND(packet, hci_delete_stored_link_key)){
3878         if (hci_stack->link_key_db){
3879             reverse_bd_addr(&packet[3], addr);
3880             hci_stack->link_key_db->delete_link_key(addr);
3881         }
3882     }
3883 
3884     if (IS_COMMAND(packet, hci_pin_code_request_negative_reply)
3885     ||  IS_COMMAND(packet, hci_pin_code_request_reply)){
3886         reverse_bd_addr(&packet[3], addr);
3887         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
3888         if (conn){
3889             connectionClearAuthenticationFlags(conn, LEGACY_PAIRING_ACTIVE);
3890         }
3891     }
3892 
3893     if (IS_COMMAND(packet, hci_user_confirmation_request_negative_reply)
3894     ||  IS_COMMAND(packet, hci_user_confirmation_request_reply)
3895     ||  IS_COMMAND(packet, hci_user_passkey_request_negative_reply)
3896     ||  IS_COMMAND(packet, hci_user_passkey_request_reply)) {
3897         reverse_bd_addr(&packet[3], addr);
3898         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
3899         if (conn){
3900             connectionClearAuthenticationFlags(conn, SSP_PAIRING_ACTIVE);
3901         }
3902     }
3903 
3904 #ifdef ENABLE_SCO_OVER_HCI
3905     // setup_synchronous_connection? Voice setting at offset 22
3906     if (IS_COMMAND(packet, hci_setup_synchronous_connection)){
3907         // TODO: compare to current setting if sco connection already active
3908         hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
3909     }
3910     // accept_synchronus_connection? Voice setting at offset 18
3911     if (IS_COMMAND(packet, hci_accept_synchronous_connection)){
3912         // TODO: compare to current setting if sco connection already active
3913         hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
3914     }
3915 #endif
3916 #endif
3917 
3918 #ifdef ENABLE_BLE
3919 #ifdef ENABLE_LE_PERIPHERAL
3920     if (IS_COMMAND(packet, hci_le_set_random_address)){
3921         hci_stack->le_random_address_set = 1;
3922         reverse_bd_addr(&packet[3], hci_stack->le_random_address);
3923     }
3924     if (IS_COMMAND(packet, hci_le_set_advertise_enable)){
3925         hci_stack->le_advertisements_active = packet[3];
3926     }
3927 #endif
3928 #ifdef ENABLE_LE_CENTRAL
3929     if (IS_COMMAND(packet, hci_le_create_connection)){
3930         // white list used?
3931         uint8_t initiator_filter_policy = packet[7];
3932         switch (initiator_filter_policy){
3933             case 0:
3934                 // whitelist not used
3935                 hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
3936                 break;
3937             case 1:
3938                 hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
3939                 break;
3940             default:
3941                 log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
3942                 break;
3943         }
3944     }
3945     if (IS_COMMAND(packet, hci_le_create_connection_cancel)){
3946         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
3947     }
3948 #endif
3949 #endif
3950 
3951     hci_stack->num_cmd_packets--;
3952 
3953     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
3954     return hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
3955 }
3956 
3957 // disconnect because of security block
3958 void hci_disconnect_security_block(hci_con_handle_t con_handle){
3959     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3960     if (!connection) return;
3961     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
3962 }
3963 
3964 
3965 // Configure Secure Simple Pairing
3966 
3967 #ifdef ENABLE_CLASSIC
3968 
3969 // enable will enable SSP during init
3970 void gap_ssp_set_enable(int enable){
3971     hci_stack->ssp_enable = enable;
3972 }
3973 
3974 static int hci_local_ssp_activated(void){
3975     return gap_ssp_supported() && hci_stack->ssp_enable;
3976 }
3977 
3978 // if set, BTstack will respond to io capability request using authentication requirement
3979 void gap_ssp_set_io_capability(int io_capability){
3980     hci_stack->ssp_io_capability = io_capability;
3981 }
3982 void gap_ssp_set_authentication_requirement(int authentication_requirement){
3983     hci_stack->ssp_authentication_requirement = authentication_requirement;
3984 }
3985 
3986 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
3987 void gap_ssp_set_auto_accept(int auto_accept){
3988     hci_stack->ssp_auto_accept = auto_accept;
3989 }
3990 #endif
3991 
3992 // va_list part of hci_send_cmd
3993 int hci_send_cmd_va_arg(const hci_cmd_t *cmd, va_list argptr){
3994     if (!hci_can_send_command_packet_now()){
3995         log_error("hci_send_cmd called but cannot send packet now");
3996         return 0;
3997     }
3998 
3999     // for HCI INITIALIZATION
4000     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
4001     hci_stack->last_cmd_opcode = cmd->opcode;
4002 
4003     hci_reserve_packet_buffer();
4004     uint8_t * packet = hci_stack->hci_packet_buffer;
4005     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
4006     int err = hci_send_cmd_packet(packet, size);
4007 
4008     // release packet buffer for synchronous transport implementations
4009     if (hci_transport_synchronous()){
4010         hci_release_packet_buffer();
4011         hci_emit_transport_packet_sent();
4012     }
4013 
4014     return err;
4015 }
4016 
4017 /**
4018  * pre: numcmds >= 0 - it's allowed to send a command to the controller
4019  */
4020 int hci_send_cmd(const hci_cmd_t *cmd, ...){
4021     va_list argptr;
4022     va_start(argptr, cmd);
4023     int res = hci_send_cmd_va_arg(cmd, argptr);
4024     va_end(argptr);
4025     return res;
4026 }
4027 
4028 // Create various non-HCI events.
4029 // TODO: generalize, use table similar to hci_create_command
4030 
4031 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
4032     // dump packet
4033     if (dump) {
4034         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
4035     }
4036 
4037     // dispatch to all event handlers
4038     btstack_linked_list_iterator_t it;
4039     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
4040     while (btstack_linked_list_iterator_has_next(&it)){
4041         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
4042         entry->callback(HCI_EVENT_PACKET, 0, event, size);
4043     }
4044 }
4045 
4046 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
4047     if (!hci_stack->acl_packet_handler) return;
4048     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
4049 }
4050 
4051 #ifdef ENABLE_CLASSIC
4052 static void hci_notify_if_sco_can_send_now(void){
4053     // notify SCO sender if waiting
4054     if (!hci_stack->sco_waiting_for_can_send_now) return;
4055     if (hci_can_send_sco_packet_now()){
4056         hci_stack->sco_waiting_for_can_send_now = 0;
4057         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
4058         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
4059         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
4060     }
4061 }
4062 
4063 // parsing end emitting has been merged to reduce code size
4064 static void gap_inquiry_explode(uint8_t * packet){
4065     uint8_t event[19+GAP_INQUIRY_MAX_NAME_LEN];
4066 
4067     uint8_t * eir_data;
4068     ad_context_t context;
4069     const uint8_t * name;
4070     uint8_t         name_len;
4071 
4072     int event_type = hci_event_packet_get_type(packet);
4073     int num_reserved_fields = event_type == HCI_EVENT_INQUIRY_RESULT ? 2 : 1;    // 2 for old event, 1 otherwise
4074     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
4075 
4076     // event[1] is set at the end
4077     int i;
4078     for (i=0; i<num_responses;i++){
4079         memset(event, 0, sizeof(event));
4080         event[0] = GAP_EVENT_INQUIRY_RESULT;
4081         uint8_t event_size = 18;    // if name is not set by EIR
4082 
4083         memcpy(&event[2],  &packet[3 +                                             i*6], 6); // bd_addr
4084         event[8] =          packet[3 + num_responses*(6)                         + i*1];     // page_scan_repetition_mode
4085         memcpy(&event[9],  &packet[3 + num_responses*(6+1+num_reserved_fields)   + i*3], 3); // class of device
4086         memcpy(&event[12], &packet[3 + num_responses*(6+1+num_reserved_fields+3) + i*2], 2); // clock offset
4087 
4088         switch (event_type){
4089             case HCI_EVENT_INQUIRY_RESULT:
4090                 // 14,15,16,17 = 0, size 18
4091                 break;
4092             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
4093                 event[14] = 1;
4094                 event[15] = packet [3 + num_responses*(6+1+num_reserved_fields+3+2) + i*1]; // rssi
4095                 // 16,17 = 0, size 18
4096                 break;
4097             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
4098                 event[14] = 1;
4099                 event[15] = packet [3 + num_responses*(6+1+num_reserved_fields+3+2) + i*1]; // rssi
4100                 // for EIR packets, there is only one reponse in it
4101                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
4102                 name = NULL;
4103                 // EIR data is 240 bytes in EIR event
4104                 for (ad_iterator_init(&context, 240, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
4105                     uint8_t data_type    = ad_iterator_get_data_type(&context);
4106                     uint8_t data_size    = ad_iterator_get_data_len(&context);
4107                     const uint8_t * data = ad_iterator_get_data(&context);
4108                     // Prefer Complete Local Name over Shortend Local Name
4109                     switch (data_type){
4110                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
4111                             if (name) continue;
4112                             /* explicit fall-through */
4113                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
4114                             name = data;
4115                             name_len = data_size;
4116                             break;
4117                         default:
4118                             break;
4119                     }
4120                 }
4121                 if (name){
4122                     event[16] = 1;
4123                     // truncate name if needed
4124                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
4125                     event[17] = len;
4126                     memcpy(&event[18], name, len);
4127                     event_size += len;
4128                 }
4129                 break;
4130         }
4131         event[1] = event_size - 2;
4132         hci_emit_event(event, event_size, 1);
4133     }
4134 }
4135 #endif
4136 
4137 void hci_emit_state(void){
4138     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
4139     uint8_t event[3];
4140     event[0] = BTSTACK_EVENT_STATE;
4141     event[1] = sizeof(event) - 2;
4142     event[2] = hci_stack->state;
4143     hci_emit_event(event, sizeof(event), 1);
4144 }
4145 
4146 #ifdef ENABLE_CLASSIC
4147 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
4148     uint8_t event[13];
4149     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
4150     event[1] = sizeof(event) - 2;
4151     event[2] = status;
4152     little_endian_store_16(event, 3, con_handle);
4153     reverse_bd_addr(address, &event[5]);
4154     event[11] = 1; // ACL connection
4155     event[12] = 0; // encryption disabled
4156     hci_emit_event(event, sizeof(event), 1);
4157 }
4158 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
4159     if (disable_l2cap_timeouts) return;
4160     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
4161     uint8_t event[4];
4162     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
4163     event[1] = sizeof(event) - 2;
4164     little_endian_store_16(event, 2, conn->con_handle);
4165     hci_emit_event(event, sizeof(event), 1);
4166 }
4167 #endif
4168 
4169 #ifdef ENABLE_BLE
4170 #ifdef ENABLE_LE_CENTRAL
4171 static void hci_emit_le_connection_complete(uint8_t address_type, bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
4172     uint8_t event[21];
4173     event[0] = HCI_EVENT_LE_META;
4174     event[1] = sizeof(event) - 2;
4175     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
4176     event[3] = status;
4177     little_endian_store_16(event, 4, con_handle);
4178     event[6] = 0; // TODO: role
4179     event[7] = address_type;
4180     reverse_bd_addr(address, &event[8]);
4181     little_endian_store_16(event, 14, 0); // interval
4182     little_endian_store_16(event, 16, 0); // latency
4183     little_endian_store_16(event, 18, 0); // supervision timeout
4184     event[20] = 0; // master clock accuracy
4185     hci_emit_event(event, sizeof(event), 1);
4186 }
4187 #endif
4188 #endif
4189 
4190 static void hci_emit_transport_packet_sent(void){
4191     // notify upper stack that it might be possible to send again
4192     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
4193     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
4194 }
4195 
4196 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
4197     uint8_t event[6];
4198     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
4199     event[1] = sizeof(event) - 2;
4200     event[2] = 0; // status = OK
4201     little_endian_store_16(event, 3, con_handle);
4202     event[5] = reason;
4203     hci_emit_event(event, sizeof(event), 1);
4204 }
4205 
4206 static void hci_emit_nr_connections_changed(void){
4207     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
4208     uint8_t event[3];
4209     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
4210     event[1] = sizeof(event) - 2;
4211     event[2] = nr_hci_connections();
4212     hci_emit_event(event, sizeof(event), 1);
4213 }
4214 
4215 static void hci_emit_hci_open_failed(void){
4216     log_info("BTSTACK_EVENT_POWERON_FAILED");
4217     uint8_t event[2];
4218     event[0] = BTSTACK_EVENT_POWERON_FAILED;
4219     event[1] = sizeof(event) - 2;
4220     hci_emit_event(event, sizeof(event), 1);
4221 }
4222 
4223 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
4224     log_info("hci_emit_dedicated_bonding_result %u ", status);
4225     uint8_t event[9];
4226     int pos = 0;
4227     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
4228     event[pos++] = sizeof(event) - 2;
4229     event[pos++] = status;
4230     reverse_bd_addr(address, &event[pos]);
4231     hci_emit_event(event, sizeof(event), 1);
4232 }
4233 
4234 
4235 #ifdef ENABLE_CLASSIC
4236 
4237 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
4238     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
4239     uint8_t event[5];
4240     int pos = 0;
4241     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
4242     event[pos++] = sizeof(event) - 2;
4243     little_endian_store_16(event, 2, con_handle);
4244     pos += 2;
4245     event[pos++] = level;
4246     hci_emit_event(event, sizeof(event), 1);
4247 }
4248 
4249 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
4250     if (!connection) return LEVEL_0;
4251     if ((connection->authentication_flags & CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
4252     return gap_security_level_for_link_key_type(connection->link_key_type);
4253 }
4254 
4255 static void hci_emit_discoverable_enabled(uint8_t enabled){
4256     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
4257     uint8_t event[3];
4258     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
4259     event[1] = sizeof(event) - 2;
4260     event[2] = enabled;
4261     hci_emit_event(event, sizeof(event), 1);
4262 }
4263 
4264 #ifdef ENABLE_CLASSIC
4265 // query if remote side supports eSCO
4266 int hci_remote_esco_supported(hci_con_handle_t con_handle){
4267     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4268     if (!connection) return 0;
4269     return connection->remote_supported_feature_eSCO;
4270 }
4271 
4272 // query if remote side supports SSP
4273 int hci_remote_ssp_supported(hci_con_handle_t con_handle){
4274     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4275     if (!connection) return 0;
4276     return (connection->bonding_flags & BONDING_REMOTE_SUPPORTS_SSP) ? 1 : 0;
4277 }
4278 
4279 int gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
4280     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
4281 }
4282 #endif
4283 
4284 // GAP API
4285 /**
4286  * @bbrief enable/disable bonding. default is enabled
4287  * @praram enabled
4288  */
4289 void gap_set_bondable_mode(int enable){
4290     hci_stack->bondable = enable ? 1 : 0;
4291 }
4292 /**
4293  * @brief Get bondable mode.
4294  * @return 1 if bondable
4295  */
4296 int gap_get_bondable_mode(void){
4297     return hci_stack->bondable;
4298 }
4299 
4300 /**
4301  * @brief map link keys to security levels
4302  */
4303 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
4304     switch (link_key_type){
4305         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4306             return LEVEL_4;
4307         case COMBINATION_KEY:
4308         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
4309             return LEVEL_3;
4310         default:
4311             return LEVEL_2;
4312     }
4313 }
4314 
4315 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
4316     log_info("gap_mitm_protection_required_for_security_level %u", level);
4317     return level > LEVEL_2;
4318 }
4319 
4320 /**
4321  * @brief get current security level
4322  */
4323 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
4324     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4325     if (!connection) return LEVEL_0;
4326     return gap_security_level_for_connection(connection);
4327 }
4328 
4329 /**
4330  * @brief request connection to device to
4331  * @result GAP_AUTHENTICATION_RESULT
4332  */
4333 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
4334     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4335     if (!connection){
4336         hci_emit_security_level(con_handle, LEVEL_0);
4337         return;
4338     }
4339     gap_security_level_t current_level = gap_security_level(con_handle);
4340     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
4341         requested_level, connection->requested_security_level, current_level);
4342 
4343     // assumption: earlier requested security higher than current level => security request is active
4344     if (current_level < connection->requested_security_level){
4345         if (connection->requested_security_level < requested_level){
4346             // increase requested level as new level is higher
4347 
4348             // TODO: handle re-authentication when done
4349 
4350             connection->requested_security_level = requested_level;
4351         }
4352         return;
4353     }
4354 
4355     // no request active, notify if security sufficient
4356     if (requested_level <= current_level){
4357         hci_emit_security_level(con_handle, current_level);
4358         return;
4359     }
4360 
4361     // start pairing to increase security level
4362     connection->requested_security_level = requested_level;
4363 
4364 #if 0
4365     // sending encryption request without a link key results in an error.
4366     // TODO: figure out how to use it properly
4367 
4368     // would enabling ecnryption suffice (>= LEVEL_2)?
4369     if (hci_stack->link_key_db){
4370         link_key_type_t link_key_type;
4371         link_key_t      link_key;
4372         if (hci_stack->link_key_db->get_link_key( &connection->address, &link_key, &link_key_type)){
4373             if (gap_security_level_for_link_key_type(link_key_type) >= requested_level){
4374                 connection->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
4375                 return;
4376             }
4377         }
4378     }
4379 #endif
4380 
4381     // start to authenticate connection
4382     connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
4383     hci_run();
4384 }
4385 
4386 /**
4387  * @brief start dedicated bonding with device. disconnect after bonding
4388  * @param device
4389  * @param request MITM protection
4390  * @result GAP_DEDICATED_BONDING_COMPLETE
4391  */
4392 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
4393 
4394     // create connection state machine
4395     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_CLASSIC);
4396 
4397     if (!connection){
4398         return BTSTACK_MEMORY_ALLOC_FAILED;
4399     }
4400 
4401     // delete linkn key
4402     gap_drop_link_key_for_bd_addr(device);
4403 
4404     // configure LEVEL_2/3, dedicated bonding
4405     connection->state = SEND_CREATE_CONNECTION;
4406     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
4407     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
4408     connection->bonding_flags = BONDING_DEDICATED;
4409 
4410     // wait for GAP Security Result and send GAP Dedicated Bonding complete
4411 
4412     // handle: connnection failure (connection complete != ok)
4413     // handle: authentication failure
4414     // handle: disconnect on done
4415 
4416     hci_run();
4417 
4418     return 0;
4419 }
4420 #endif
4421 
4422 void gap_set_local_name(const char * local_name){
4423     hci_stack->local_name = local_name;
4424 }
4425 
4426 
4427 #ifdef ENABLE_BLE
4428 
4429 #ifdef ENABLE_LE_CENTRAL
4430 void gap_start_scan(void){
4431     hci_stack->le_scanning_enabled = 1;
4432     hci_run();
4433 }
4434 
4435 void gap_stop_scan(void){
4436     hci_stack->le_scanning_enabled = 0;
4437     hci_run();
4438 }
4439 
4440 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
4441     hci_stack->le_scan_type     = scan_type;
4442     hci_stack->le_scan_interval = scan_interval;
4443     hci_stack->le_scan_window   = scan_window;
4444     hci_run();
4445 }
4446 
4447 uint8_t gap_connect(bd_addr_t addr, bd_addr_type_t addr_type){
4448     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
4449     if (!conn){
4450         log_info("gap_connect: no connection exists yet, creating context");
4451         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
4452         if (!conn){
4453             // notify client that alloc failed
4454             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
4455             log_info("gap_connect: failed to alloc hci_connection_t");
4456             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
4457         }
4458         conn->state = SEND_CREATE_CONNECTION;
4459         log_info("gap_connect: send create connection next");
4460         hci_run();
4461         return 0;
4462     }
4463 
4464     if (!hci_is_le_connection(conn) ||
4465         conn->state == SEND_CREATE_CONNECTION ||
4466         conn->state == SENT_CREATE_CONNECTION) {
4467         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
4468         log_error("gap_connect: classic connection or connect is already being created");
4469         return GATT_CLIENT_IN_WRONG_STATE;
4470     }
4471 
4472     log_info("gap_connect: context exists with state %u", conn->state);
4473     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, 0);
4474     hci_run();
4475     return 0;
4476 }
4477 
4478 // @assumption: only a single outgoing LE Connection exists
4479 static hci_connection_t * gap_get_outgoing_connection(void){
4480     btstack_linked_item_t *it;
4481     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
4482         hci_connection_t * conn = (hci_connection_t *) it;
4483         if (!hci_is_le_connection(conn)) continue;
4484         switch (conn->state){
4485             case SEND_CREATE_CONNECTION:
4486             case SENT_CREATE_CONNECTION:
4487             case SENT_CANCEL_CONNECTION:
4488                 return conn;
4489             default:
4490                 break;
4491         };
4492     }
4493     return NULL;
4494 }
4495 
4496 uint8_t gap_connect_cancel(void){
4497     hci_connection_t * conn = gap_get_outgoing_connection();
4498     if (!conn) return 0;
4499     switch (conn->state){
4500         case SEND_CREATE_CONNECTION:
4501             // skip sending create connection and emit event instead
4502             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
4503             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
4504             btstack_memory_hci_connection_free( conn );
4505             break;
4506         case SENT_CREATE_CONNECTION:
4507             // request to send cancel connection
4508             conn->state = SEND_CANCEL_CONNECTION;
4509             hci_run();
4510             break;
4511         default:
4512             break;
4513     }
4514     return 0;
4515 }
4516 #endif
4517 
4518 #ifdef ENABLE_LE_CENTRAL
4519 /**
4520  * @brief Set connection parameters for outgoing connections
4521  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
4522  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
4523  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
4524  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
4525  * @param conn_latency, default: 4
4526  * @param supervision_timeout (unit: 10ms), default: 720 ms
4527  * @param min_ce_length (unit: 0.625ms), default: 10 ms
4528  * @param max_ce_length (unit: 0.625ms), default: 30 ms
4529  */
4530 
4531 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
4532     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
4533     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
4534     hci_stack->le_connection_scan_interval = conn_scan_interval;
4535     hci_stack->le_connection_scan_window = conn_scan_window;
4536     hci_stack->le_connection_interval_min = conn_interval_min;
4537     hci_stack->le_connection_interval_max = conn_interval_max;
4538     hci_stack->le_connection_latency = conn_latency;
4539     hci_stack->le_supervision_timeout = supervision_timeout;
4540     hci_stack->le_minimum_ce_length = min_ce_length;
4541     hci_stack->le_maximum_ce_length = max_ce_length;
4542 }
4543 #endif
4544 
4545 /**
4546  * @brief Updates the connection parameters for a given LE connection
4547  * @param handle
4548  * @param conn_interval_min (unit: 1.25ms)
4549  * @param conn_interval_max (unit: 1.25ms)
4550  * @param conn_latency
4551  * @param supervision_timeout (unit: 10ms)
4552  * @returns 0 if ok
4553  */
4554 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
4555     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
4556     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4557     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
4558     connection->le_conn_interval_min = conn_interval_min;
4559     connection->le_conn_interval_max = conn_interval_max;
4560     connection->le_conn_latency = conn_latency;
4561     connection->le_supervision_timeout = supervision_timeout;
4562     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
4563     hci_run();
4564     return 0;
4565 }
4566 
4567 /**
4568  * @brief Request an update of the connection parameter for a given LE connection
4569  * @param handle
4570  * @param conn_interval_min (unit: 1.25ms)
4571  * @param conn_interval_max (unit: 1.25ms)
4572  * @param conn_latency
4573  * @param supervision_timeout (unit: 10ms)
4574  * @returns 0 if ok
4575  */
4576 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
4577     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
4578     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4579     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
4580     connection->le_conn_interval_min = conn_interval_min;
4581     connection->le_conn_interval_max = conn_interval_max;
4582     connection->le_conn_latency = conn_latency;
4583     connection->le_supervision_timeout = supervision_timeout;
4584     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
4585     hci_run();
4586     return 0;
4587 }
4588 
4589 #ifdef ENABLE_LE_PERIPHERAL
4590 
4591 static void gap_advertisments_changed(void){
4592     // disable advertisements before updating adv, scan data, or adv params
4593     if (hci_stack->le_advertisements_active){
4594         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE | LE_ADVERTISEMENT_TASKS_ENABLE;
4595     }
4596     hci_run();
4597 }
4598 
4599 /**
4600  * @brief Set Advertisement Data
4601  * @param advertising_data_length
4602  * @param advertising_data (max 31 octets)
4603  * @note data is not copied, pointer has to stay valid
4604  */
4605 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
4606     hci_stack->le_advertisements_data_len = advertising_data_length;
4607     hci_stack->le_advertisements_data = advertising_data;
4608     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
4609     gap_advertisments_changed();
4610 }
4611 
4612 /**
4613  * @brief Set Scan Response Data
4614  * @param advertising_data_length
4615  * @param advertising_data (max 31 octets)
4616  * @note data is not copied, pointer has to stay valid
4617  */
4618 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
4619     hci_stack->le_scan_response_data_len = scan_response_data_length;
4620     hci_stack->le_scan_response_data = scan_response_data;
4621     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
4622     gap_advertisments_changed();
4623 }
4624 
4625 /**
4626  * @brief Set Advertisement Parameters
4627  * @param adv_int_min
4628  * @param adv_int_max
4629  * @param adv_type
4630  * @param direct_address_type
4631  * @param direct_address
4632  * @param channel_map
4633  * @param filter_policy
4634  *
4635  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
4636  */
4637  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
4638     uint8_t direct_address_typ, bd_addr_t direct_address,
4639     uint8_t channel_map, uint8_t filter_policy) {
4640 
4641     hci_stack->le_advertisements_interval_min = adv_int_min;
4642     hci_stack->le_advertisements_interval_max = adv_int_max;
4643     hci_stack->le_advertisements_type = adv_type;
4644     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
4645     hci_stack->le_advertisements_channel_map = channel_map;
4646     hci_stack->le_advertisements_filter_policy = filter_policy;
4647     memcpy(hci_stack->le_advertisements_direct_address, direct_address, 6);
4648 
4649     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
4650     gap_advertisments_changed();
4651  }
4652 
4653 /**
4654  * @brief Enable/Disable Advertisements
4655  * @param enabled
4656  */
4657 void gap_advertisements_enable(int enabled){
4658     hci_stack->le_advertisements_enabled = enabled;
4659     if (enabled && !hci_stack->le_advertisements_active){
4660         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
4661     }
4662     if (!enabled && hci_stack->le_advertisements_active){
4663         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE;
4664     }
4665     hci_run();
4666 }
4667 
4668 #endif
4669 
4670 void hci_le_set_own_address_type(uint8_t own_address_type){
4671     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
4672     if (own_address_type == hci_stack->le_own_addr_type) return;
4673     hci_stack->le_own_addr_type = own_address_type;
4674 
4675 #ifdef ENABLE_LE_PERIPHERAL
4676     // update advertisement parameters, too
4677     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
4678     gap_advertisments_changed();
4679 #endif
4680 #ifdef ENABLE_LE_CENTRAL
4681     // note: we don't update scan parameters or modify ongoing connection attempts
4682 #endif
4683 }
4684 
4685 #endif
4686 
4687 uint8_t gap_disconnect(hci_con_handle_t handle){
4688     hci_connection_t * conn = hci_connection_for_handle(handle);
4689     if (!conn){
4690         hci_emit_disconnection_complete(handle, 0);
4691         return 0;
4692     }
4693     // ignore if already disconnected
4694     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
4695         return 0;
4696     }
4697     conn->state = SEND_DISCONNECT;
4698     hci_run();
4699     return 0;
4700 }
4701 
4702 /**
4703  * @brief Get connection type
4704  * @param con_handle
4705  * @result connection_type
4706  */
4707 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
4708     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
4709     if (!conn) return GAP_CONNECTION_INVALID;
4710     switch (conn->address_type){
4711         case BD_ADDR_TYPE_LE_PUBLIC:
4712         case BD_ADDR_TYPE_LE_RANDOM:
4713             return GAP_CONNECTION_LE;
4714         case BD_ADDR_TYPE_SCO:
4715             return GAP_CONNECTION_SCO;
4716         case BD_ADDR_TYPE_CLASSIC:
4717             return GAP_CONNECTION_ACL;
4718         default:
4719             return GAP_CONNECTION_INVALID;
4720     }
4721 }
4722 
4723 #ifdef ENABLE_BLE
4724 
4725 uint8_t gap_le_set_phy(hci_con_handle_t connection_handle, uint8_t all_phys, uint8_t tx_phys, uint8_t rx_phys, uint8_t phy_options){
4726     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
4727     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
4728 
4729     conn->le_phy_update_all_phys    = all_phys;
4730     conn->le_phy_update_tx_phys     = tx_phys;
4731     conn->le_phy_update_rx_phys     = rx_phys;
4732     conn->le_phy_update_phy_options = phy_options;
4733 
4734     hci_run();
4735 
4736     return 0;
4737 }
4738 
4739 #ifdef ENABLE_LE_CENTRAL
4740 /**
4741  * @brief Auto Connection Establishment - Start Connecting to device
4742  * @param address_typ
4743  * @param address
4744  * @returns 0 if ok
4745  */
4746 int gap_auto_connection_start(bd_addr_type_t address_type, bd_addr_t address){
4747     // check capacity
4748     int num_entries = btstack_linked_list_count(&hci_stack->le_whitelist);
4749     if (num_entries >= hci_stack->le_whitelist_capacity) return ERROR_CODE_MEMORY_CAPACITY_EXCEEDED;
4750     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
4751     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
4752     entry->address_type = address_type;
4753     memcpy(entry->address, address, 6);
4754     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
4755     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
4756     hci_run();
4757     return 0;
4758 }
4759 
4760 static void hci_remove_from_whitelist(bd_addr_type_t address_type, bd_addr_t address){
4761     btstack_linked_list_iterator_t it;
4762     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
4763     while (btstack_linked_list_iterator_has_next(&it)){
4764         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
4765         if (entry->address_type != address_type) continue;
4766         if (memcmp(entry->address, address, 6) != 0) continue;
4767         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
4768             // remove from controller if already present
4769             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
4770             continue;
4771         }
4772         // direclty remove entry from whitelist
4773         btstack_linked_list_iterator_remove(&it);
4774         btstack_memory_whitelist_entry_free(entry);
4775     }
4776 }
4777 
4778 /**
4779  * @brief Auto Connection Establishment - Stop Connecting to device
4780  * @param address_typ
4781  * @param address
4782  * @returns 0 if ok
4783  */
4784 int gap_auto_connection_stop(bd_addr_type_t address_type, bd_addr_t address){
4785     hci_remove_from_whitelist(address_type, address);
4786     hci_run();
4787     return 0;
4788 }
4789 
4790 /**
4791  * @brief Auto Connection Establishment - Stop everything
4792  * @note  Convenience function to stop all active auto connection attempts
4793  */
4794 void gap_auto_connection_stop_all(void){
4795     btstack_linked_list_iterator_t it;
4796     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
4797     while (btstack_linked_list_iterator_has_next(&it)){
4798         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
4799         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
4800             // remove from controller if already present
4801             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
4802             continue;
4803         }
4804         // directly remove entry from whitelist
4805         btstack_linked_list_iterator_remove(&it);
4806         btstack_memory_whitelist_entry_free(entry);
4807     }
4808     hci_run();
4809 }
4810 
4811 uint16_t gap_le_connection_interval(hci_con_handle_t connection_handle){
4812     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
4813     if (!conn) return 0;
4814     return conn->le_connection_interval;
4815 }
4816 #endif
4817 #endif
4818 
4819 #ifdef ENABLE_CLASSIC
4820 /**
4821  * @brief Set Extended Inquiry Response data
4822  * @param eir_data size 240 bytes, is not copied make sure memory is accessible during stack startup
4823  * @note has to be done before stack starts up
4824  */
4825 void gap_set_extended_inquiry_response(const uint8_t * data){
4826     hci_stack->eir_data = data;
4827 }
4828 
4829 /**
4830  * @brief Start GAP Classic Inquiry
4831  * @param duration in 1.28s units
4832  * @return 0 if ok
4833  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
4834  */
4835 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
4836     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
4837     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
4838     if (duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN || duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX){
4839         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
4840     }
4841     hci_stack->inquiry_state = duration_in_1280ms_units;
4842     hci_run();
4843     return 0;
4844 }
4845 
4846 /**
4847  * @brief Stop GAP Classic Inquiry
4848  * @returns 0 if ok
4849  */
4850 int gap_inquiry_stop(void){
4851     if (hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN && hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX) {
4852         // emit inquiry complete event, before it even started
4853         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
4854         hci_emit_event(event, sizeof(event), 1);
4855         return 0;
4856     }
4857     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
4858     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
4859     hci_run();
4860     return 0;
4861 }
4862 
4863 
4864 /**
4865  * @brief Remote Name Request
4866  * @param addr
4867  * @param page_scan_repetition_mode
4868  * @param clock_offset only used when bit 15 is set
4869  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
4870  */
4871 int gap_remote_name_request(bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
4872     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
4873     memcpy(hci_stack->remote_name_addr, addr, 6);
4874     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
4875     hci_stack->remote_name_clock_offset = clock_offset;
4876     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
4877     hci_run();
4878     return 0;
4879 }
4880 
4881 static int gap_pairing_set_state_and_run(bd_addr_t addr, uint8_t state){
4882     hci_stack->gap_pairing_state = state;
4883     memcpy(hci_stack->gap_pairing_addr, addr, 6);
4884     hci_run();
4885     return 0;
4886 }
4887 
4888 /**
4889  * @brief Legacy Pairing Pin Code Response
4890  * @param addr
4891  * @param pin
4892  * @return 0 if ok
4893  */
4894 int gap_pin_code_response(bd_addr_t addr, const char * pin){
4895     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
4896     hci_stack->gap_pairing_input.gap_pairing_pin = pin;
4897     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
4898 }
4899 
4900 /**
4901  * @brief Abort Legacy Pairing
4902  * @param addr
4903  * @param pin
4904  * @return 0 if ok
4905  */
4906 int gap_pin_code_negative(bd_addr_t addr){
4907     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
4908     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
4909 }
4910 
4911 /**
4912  * @brief SSP Passkey Response
4913  * @param addr
4914  * @param passkey
4915  * @return 0 if ok
4916  */
4917 int gap_ssp_passkey_response(bd_addr_t addr, uint32_t passkey){
4918     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
4919     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
4920     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
4921 }
4922 
4923 /**
4924  * @brief Abort SSP Passkey Entry/Pairing
4925  * @param addr
4926  * @param pin
4927  * @return 0 if ok
4928  */
4929 int gap_ssp_passkey_negative(bd_addr_t addr){
4930     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
4931     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
4932 }
4933 
4934 /**
4935  * @brief Accept SSP Numeric Comparison
4936  * @param addr
4937  * @param passkey
4938  * @return 0 if ok
4939  */
4940 int gap_ssp_confirmation_response(bd_addr_t addr){
4941     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
4942     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
4943 }
4944 
4945 /**
4946  * @brief Abort SSP Numeric Comparison/Pairing
4947  * @param addr
4948  * @param pin
4949  * @return 0 if ok
4950  */
4951 int gap_ssp_confirmation_negative(bd_addr_t addr){
4952     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
4953     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
4954 }
4955 
4956 /**
4957  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
4958  * @param inquiry_mode see bluetooth_defines.h
4959  */
4960 void hci_set_inquiry_mode(inquiry_mode_t mode){
4961     hci_stack->inquiry_mode = mode;
4962 }
4963 
4964 /**
4965  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
4966  */
4967 void hci_set_sco_voice_setting(uint16_t voice_setting){
4968     hci_stack->sco_voice_setting = voice_setting;
4969 }
4970 
4971 /**
4972  * @brief Get SCO Voice Setting
4973  * @return current voice setting
4974  */
4975 uint16_t hci_get_sco_voice_setting(void){
4976     return hci_stack->sco_voice_setting;
4977 }
4978 
4979 #ifdef ENABLE_CLASSIC
4980 static int hci_have_usb_transport(void){
4981     if (!hci_stack->hci_transport) return 0;
4982     const char * transport_name = hci_stack->hci_transport->name;
4983     if (!transport_name) return 0;
4984     return (transport_name[0] == 'H') && (transport_name[1] == '2');
4985 }
4986 #endif
4987 
4988 /** @brief Get SCO packet length for current SCO Voice setting
4989  *  @note  Using SCO packets of the exact length is required for USB transfer
4990  *  @return Length of SCO packets in bytes (not audio frames)
4991  */
4992 int hci_get_sco_packet_length(void){
4993     int sco_packet_length = 0;
4994 
4995 #ifdef ENABLE_CLASSIC
4996 #ifdef ENABLE_SCO_OVER_HCI
4997 
4998     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
4999     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
5000 
5001     if (hci_have_usb_transport()){
5002         // see Core Spec for H2 USB Transfer.
5003         // 3 byte SCO header + 24 bytes per connection
5004         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
5005         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
5006     } else {
5007         // 3 byte SCO header + SCO packet size over the air (60 bytes)
5008         sco_packet_length = 3 + 60 * multiplier;
5009         // assert that it still fits inside an SCO buffer
5010         if (sco_packet_length > hci_stack->sco_data_packet_length){
5011             sco_packet_length = 3 + 60;
5012         }
5013     }
5014 #endif
5015 #endif
5016     return sco_packet_length;
5017 }
5018 
5019 /**
5020 * @brief Sets the master/slave policy
5021 * @param policy (0: attempt to become master, 1: let connecting device decide)
5022 */
5023 void hci_set_master_slave_policy(uint8_t policy){
5024     hci_stack->master_slave_policy = policy;
5025 }
5026 
5027 #endif
5028 
5029 HCI_STATE hci_get_state(void){
5030     return hci_stack->state;
5031 }
5032 
5033 
5034 /**
5035  * @brief Set callback for Bluetooth Hardware Error
5036  */
5037 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
5038     hci_stack->hardware_error_callback = fn;
5039 }
5040 
5041 void hci_disconnect_all(void){
5042     btstack_linked_list_iterator_t it;
5043     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
5044     while (btstack_linked_list_iterator_has_next(&it)){
5045         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
5046         if (con->state == SENT_DISCONNECT) continue;
5047         con->state = SEND_DISCONNECT;
5048     }
5049     hci_run();
5050 }
5051 
5052 uint16_t hci_get_manufacturer(void){
5053     return hci_stack->manufacturer;
5054 }
5055 
5056 #ifdef ENABLE_BLE
5057 
5058 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
5059     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
5060     if (!hci_con) return NULL;
5061     return &hci_con->sm_connection;
5062 }
5063 
5064 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
5065 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
5066 
5067 int gap_encryption_key_size(hci_con_handle_t con_handle){
5068     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
5069     if (!sm_conn) return 0;     // wrong connection
5070     if (!sm_conn->sm_connection_encrypted) return 0;
5071     return sm_conn->sm_actual_encryption_key_size;
5072 }
5073 
5074 int gap_authenticated(hci_con_handle_t con_handle){
5075     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
5076     if (!sm_conn) return 0;     // wrong connection
5077     if (!sm_conn->sm_connection_encrypted) return 0; // unencrypted connection cannot be authenticated
5078     return sm_conn->sm_connection_authenticated;
5079 }
5080 
5081 int gap_secure_connection(hci_con_handle_t con_handle){
5082     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
5083     if (!sm_conn) return 0;     // wrong connection
5084     if (!sm_conn->sm_connection_encrypted) return 0; // unencrypted connection cannot be authenticated
5085     return sm_conn->sm_connection_sc;
5086 }
5087 
5088 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
5089     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
5090     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
5091     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
5092     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
5093     return sm_conn->sm_connection_authorization_state;
5094 }
5095 #endif
5096 
5097 #ifdef ENABLE_CLASSIC
5098 uint8_t gap_sniff_mode_enter(hci_con_handle_t con_handle, uint16_t sniff_min_interval, uint16_t sniff_max_interval, uint16_t sniff_attempt, uint16_t sniff_timeout){
5099     hci_connection_t * conn = hci_connection_for_handle(con_handle);
5100     if (!conn) return GAP_CONNECTION_INVALID;
5101     conn->sniff_min_interval = sniff_min_interval;
5102     conn->sniff_max_interval = sniff_max_interval;
5103     conn->sniff_attempt = sniff_attempt;
5104     conn->sniff_timeout = sniff_timeout;
5105     hci_run();
5106     return 0;
5107 }
5108 
5109 /**
5110  * @brief Exit Sniff mode
5111  * @param con_handle
5112  @ @return 0 if ok
5113  */
5114 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
5115     hci_connection_t * conn = hci_connection_for_handle(con_handle);
5116     if (!conn) return GAP_CONNECTION_INVALID;
5117     conn->sniff_min_interval = 0xffff;
5118     hci_run();
5119     return 0;
5120 }
5121 #endif
5122 
5123 void hci_halting_defer(void){
5124     if (hci_stack->state != HCI_STATE_HALTING) return;
5125     switch (hci_stack->substate){
5126         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
5127         case HCI_HALTING_CLOSE:
5128             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
5129             break;
5130         default:
5131             break;
5132     }
5133 }
5134