xref: /btstack/src/hci.c (revision dcd678ba09afffc51fbac08984ef5711233a35c6)
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_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason);
147 static void hci_emit_nr_connections_changed(void);
148 static void hci_emit_hci_open_failed(void);
149 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status);
150 static void hci_emit_event(uint8_t * event, uint16_t size, int dump);
151 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size);
152 static void hci_run(void);
153 static int  hci_is_le_connection(hci_connection_t * connection);
154 static int  hci_number_free_acl_slots_for_connection_type( bd_addr_type_t address_type);
155 
156 #ifdef ENABLE_BLE
157 #ifdef ENABLE_LE_CENTRAL
158 // called from test/ble_client/advertising_data_parser.c
159 void le_handle_advertisement_report(uint8_t *packet, int size);
160 static void hci_remove_from_whitelist(bd_addr_type_t address_type, bd_addr_t address);
161 #endif
162 #endif
163 
164 // the STACK is here
165 #ifndef HAVE_MALLOC
166 static hci_stack_t   hci_stack_static;
167 #endif
168 static hci_stack_t * hci_stack = NULL;
169 
170 #ifdef ENABLE_CLASSIC
171 // test helper
172 static uint8_t disable_l2cap_timeouts = 0;
173 #endif
174 
175 /**
176  * create connection for given address
177  *
178  * @return connection OR NULL, if no memory left
179  */
180 static hci_connection_t * create_connection_for_bd_addr_and_type(bd_addr_t addr, bd_addr_type_t addr_type){
181     log_info("create_connection_for_addr %s, type %x", bd_addr_to_str(addr), addr_type);
182     hci_connection_t * conn = btstack_memory_hci_connection_get();
183     if (!conn) return NULL;
184     memset(conn, 0, sizeof(hci_connection_t));
185     bd_addr_copy(conn->address, addr);
186     conn->address_type = addr_type;
187     conn->con_handle = 0xffff;
188     conn->authentication_flags = AUTH_FLAGS_NONE;
189     conn->bonding_flags = 0;
190     conn->requested_security_level = LEVEL_0;
191 #ifdef ENABLE_CLASSIC
192     btstack_run_loop_set_timer_handler(&conn->timeout, hci_connection_timeout_handler);
193     btstack_run_loop_set_timer_context(&conn->timeout, conn);
194     hci_connection_timestamp(conn);
195 #endif
196     conn->acl_recombination_length = 0;
197     conn->acl_recombination_pos = 0;
198     conn->num_acl_packets_sent = 0;
199     conn->num_sco_packets_sent = 0;
200     conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
201     btstack_linked_list_add(&hci_stack->connections, (btstack_linked_item_t *) conn);
202     return conn;
203 }
204 
205 
206 /**
207  * get le connection parameter range
208 *
209  * @return le connection parameter range struct
210  */
211 void gap_get_connection_parameter_range(le_connection_parameter_range_t * range){
212     *range = hci_stack->le_connection_parameter_range;
213 }
214 
215 /**
216  * set le connection parameter range
217  *
218  */
219 
220 void gap_set_connection_parameter_range(le_connection_parameter_range_t *range){
221     hci_stack->le_connection_parameter_range = *range;
222 }
223 
224 /**
225  * get hci connections iterator
226  *
227  * @return hci connections iterator
228  */
229 
230 void hci_connections_get_iterator(btstack_linked_list_iterator_t *it){
231     btstack_linked_list_iterator_init(it, &hci_stack->connections);
232 }
233 
234 /**
235  * get connection for a given handle
236  *
237  * @return connection OR NULL, if not found
238  */
239 hci_connection_t * hci_connection_for_handle(hci_con_handle_t con_handle){
240     btstack_linked_list_iterator_t it;
241     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
242     while (btstack_linked_list_iterator_has_next(&it)){
243         hci_connection_t * item = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
244         if ( item->con_handle == con_handle ) {
245             return item;
246         }
247     }
248     return NULL;
249 }
250 
251 /**
252  * get connection for given address
253  *
254  * @return connection OR NULL, if not found
255  */
256 hci_connection_t * hci_connection_for_bd_addr_and_type(bd_addr_t  addr, bd_addr_type_t addr_type){
257     btstack_linked_list_iterator_t it;
258     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
259     while (btstack_linked_list_iterator_has_next(&it)){
260         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
261         if (connection->address_type != addr_type)  continue;
262         if (memcmp(addr, connection->address, 6) != 0) continue;
263         return connection;
264     }
265     return NULL;
266 }
267 
268 
269 #ifdef ENABLE_CLASSIC
270 
271 #ifdef ENABLE_SCO_OVER_HCI
272 static int hci_number_sco_connections(void){
273     int connections = 0;
274     btstack_linked_list_iterator_t it;
275     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
276     while (btstack_linked_list_iterator_has_next(&it)){
277         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
278         if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
279         connections++;
280     }
281     return connections;
282 }
283 #endif
284 
285 static void hci_connection_timeout_handler(btstack_timer_source_t *timer){
286     hci_connection_t * connection = (hci_connection_t *) btstack_run_loop_get_timer_context(timer);
287 #ifdef HAVE_EMBEDDED_TICK
288     if (btstack_run_loop_embedded_get_ticks() > connection->timestamp + btstack_run_loop_embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
289         // connections might be timed out
290         hci_emit_l2cap_check_timeout(connection);
291     }
292 #else
293     if (btstack_run_loop_get_time_ms() > connection->timestamp + HCI_CONNECTION_TIMEOUT_MS){
294         // connections might be timed out
295         hci_emit_l2cap_check_timeout(connection);
296     }
297 #endif
298 }
299 
300 static void hci_connection_timestamp(hci_connection_t *connection){
301 #ifdef HAVE_EMBEDDED_TICK
302     connection->timestamp = btstack_run_loop_embedded_get_ticks();
303 #else
304     connection->timestamp = btstack_run_loop_get_time_ms();
305 #endif
306 }
307 
308 inline static void connectionSetAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
309     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags | flags);
310 }
311 
312 
313 inline static void connectionClearAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
314     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags & ~flags);
315 }
316 
317 /**
318  * add authentication flags and reset timer
319  * @note: assumes classic connection
320  * @note: bd_addr is passed in as litle endian uint8_t * as it is called from parsing packets
321  */
322 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
323     bd_addr_t addr;
324     reverse_bd_addr(bd_addr, addr);
325     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
326     if (conn) {
327         connectionSetAuthenticationFlags(conn, flags);
328         hci_connection_timestamp(conn);
329     }
330 }
331 
332 int  hci_authentication_active_for_handle(hci_con_handle_t handle){
333     hci_connection_t * conn = hci_connection_for_handle(handle);
334     if (!conn) return 0;
335     if (conn->authentication_flags & LEGACY_PAIRING_ACTIVE) return 1;
336     if (conn->authentication_flags & SSP_PAIRING_ACTIVE) return 1;
337     return 0;
338 }
339 
340 void gap_drop_link_key_for_bd_addr(bd_addr_t addr){
341     if (!hci_stack->link_key_db) return;
342     log_info("gap_drop_link_key_for_bd_addr: %s", bd_addr_to_str(addr));
343     hci_stack->link_key_db->delete_link_key(addr);
344 }
345 
346 void gap_store_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t type){
347     if (!hci_stack->link_key_db) return;
348     log_info("gap_store_link_key_for_bd_addr: %s, type %u", bd_addr_to_str(addr), type);
349     hci_stack->link_key_db->put_link_key(addr, link_key, type);
350 }
351 #endif
352 
353 static int hci_is_le_connection(hci_connection_t * connection){
354     return  connection->address_type == BD_ADDR_TYPE_LE_PUBLIC ||
355     connection->address_type == BD_ADDR_TYPE_LE_RANDOM;
356 }
357 
358 /**
359  * count connections
360  */
361 static int nr_hci_connections(void){
362     int count = 0;
363     btstack_linked_item_t *it;
364     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next, count++);
365     return count;
366 }
367 
368 static int hci_number_free_acl_slots_for_connection_type(bd_addr_type_t address_type){
369 
370     unsigned int num_packets_sent_classic = 0;
371     unsigned int num_packets_sent_le = 0;
372 
373     btstack_linked_item_t *it;
374     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
375         hci_connection_t * connection = (hci_connection_t *) it;
376         if (connection->address_type == BD_ADDR_TYPE_CLASSIC){
377             num_packets_sent_classic += connection->num_acl_packets_sent;
378         } else {
379             num_packets_sent_le += connection->num_acl_packets_sent;
380         }
381     }
382     log_debug("ACL classic buffers: %u used of %u", num_packets_sent_classic, hci_stack->acl_packets_total_num);
383     int free_slots_classic = hci_stack->acl_packets_total_num - num_packets_sent_classic;
384     int free_slots_le = 0;
385 
386     if (free_slots_classic < 0){
387         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);
388         return 0;
389     }
390 
391     if (hci_stack->le_acl_packets_total_num){
392         // if we have LE slots, they are used
393         free_slots_le = hci_stack->le_acl_packets_total_num - num_packets_sent_le;
394         if (free_slots_le < 0){
395             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);
396             return 0;
397         }
398     } else {
399         // otherwise, classic slots are used for LE, too
400         free_slots_classic -= num_packets_sent_le;
401         if (free_slots_classic < 0){
402             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);
403             return 0;
404         }
405     }
406 
407     switch (address_type){
408         case BD_ADDR_TYPE_UNKNOWN:
409             log_error("hci_number_free_acl_slots: unknown address type");
410             return 0;
411 
412         case BD_ADDR_TYPE_CLASSIC:
413             return free_slots_classic;
414 
415         default:
416            if (hci_stack->le_acl_packets_total_num){
417                return free_slots_le;
418            }
419            return free_slots_classic;
420     }
421 }
422 
423 int hci_number_free_acl_slots_for_handle(hci_con_handle_t con_handle){
424     // get connection type
425     hci_connection_t * connection = hci_connection_for_handle(con_handle);
426     if (!connection){
427         log_error("hci_number_free_acl_slots: handle 0x%04x not in connection list", con_handle);
428         return 0;
429     }
430     return hci_number_free_acl_slots_for_connection_type(connection->address_type);
431 }
432 
433 #ifdef ENABLE_CLASSIC
434 static int hci_number_free_sco_slots(void){
435     unsigned int num_sco_packets_sent  = 0;
436     btstack_linked_item_t *it;
437     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
438         hci_connection_t * connection = (hci_connection_t *) it;
439         num_sco_packets_sent += connection->num_sco_packets_sent;
440     }
441     if (num_sco_packets_sent > hci_stack->sco_packets_total_num){
442         log_info("hci_number_free_sco_slots:packets (%u) > total packets (%u)", num_sco_packets_sent, hci_stack->sco_packets_total_num);
443         return 0;
444     }
445     // log_info("hci_number_free_sco_slots u", handle, num_sco_packets_sent);
446     return hci_stack->sco_packets_total_num - num_sco_packets_sent;
447 }
448 #endif
449 
450 // only used to send HCI Host Number Completed Packets
451 static int hci_can_send_comand_packet_transport(void){
452     if (hci_stack->hci_packet_buffer_reserved) return 0;
453 
454     // check for async hci transport implementations
455     if (hci_stack->hci_transport->can_send_packet_now){
456         if (!hci_stack->hci_transport->can_send_packet_now(HCI_COMMAND_DATA_PACKET)){
457             return 0;
458         }
459     }
460     return 1;
461 }
462 
463 // new functions replacing hci_can_send_packet_now[_using_packet_buffer]
464 int hci_can_send_command_packet_now(void){
465     if (hci_can_send_comand_packet_transport() == 0) return 0;
466     return hci_stack->num_cmd_packets > 0;
467 }
468 
469 static int hci_transport_can_send_prepared_packet_now(uint8_t packet_type){
470     // check for async hci transport implementations
471     if (!hci_stack->hci_transport->can_send_packet_now) return 1;
472     return hci_stack->hci_transport->can_send_packet_now(packet_type);
473 }
474 
475 static int hci_can_send_prepared_acl_packet_for_address_type(bd_addr_type_t address_type){
476     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
477     return hci_number_free_acl_slots_for_connection_type(address_type) > 0;
478 }
479 
480 int hci_can_send_acl_le_packet_now(void){
481     if (hci_stack->hci_packet_buffer_reserved) return 0;
482     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_LE_PUBLIC);
483 }
484 
485 int hci_can_send_prepared_acl_packet_now(hci_con_handle_t con_handle) {
486     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
487     return hci_number_free_acl_slots_for_handle(con_handle) > 0;
488 }
489 
490 int hci_can_send_acl_packet_now(hci_con_handle_t con_handle){
491     if (hci_stack->hci_packet_buffer_reserved) return 0;
492     return hci_can_send_prepared_acl_packet_now(con_handle);
493 }
494 
495 #ifdef ENABLE_CLASSIC
496 int hci_can_send_acl_classic_packet_now(void){
497     if (hci_stack->hci_packet_buffer_reserved) return 0;
498     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_CLASSIC);
499 }
500 
501 int hci_can_send_prepared_sco_packet_now(void){
502     if (!hci_transport_can_send_prepared_packet_now(HCI_SCO_DATA_PACKET)) return 0;
503     if (!hci_stack->synchronous_flow_control_enabled) return 1;
504     return hci_number_free_sco_slots() > 0;
505 }
506 
507 int hci_can_send_sco_packet_now(void){
508     if (hci_stack->hci_packet_buffer_reserved) return 0;
509     return hci_can_send_prepared_sco_packet_now();
510 }
511 
512 void hci_request_sco_can_send_now_event(void){
513     hci_stack->sco_waiting_for_can_send_now = 1;
514     hci_notify_if_sco_can_send_now();
515 }
516 #endif
517 
518 // used for internal checks in l2cap.c
519 int hci_is_packet_buffer_reserved(void){
520     return hci_stack->hci_packet_buffer_reserved;
521 }
522 
523 // reserves outgoing packet buffer. @returns 1 if successful
524 int hci_reserve_packet_buffer(void){
525     if (hci_stack->hci_packet_buffer_reserved) {
526         log_error("hci_reserve_packet_buffer called but buffer already reserved");
527         return 0;
528     }
529     hci_stack->hci_packet_buffer_reserved = 1;
530     return 1;
531 }
532 
533 void hci_release_packet_buffer(void){
534     hci_stack->hci_packet_buffer_reserved = 0;
535 }
536 
537 // assumption: synchronous implementations don't provide can_send_packet_now as they don't keep the buffer after the call
538 static int hci_transport_synchronous(void){
539     return hci_stack->hci_transport->can_send_packet_now == NULL;
540 }
541 
542 static int hci_send_acl_packet_fragments(hci_connection_t *connection){
543 
544     // 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);
545 
546     // max ACL data packet length depends on connection type (LE vs. Classic) and available buffers
547     uint16_t max_acl_data_packet_length = hci_stack->acl_data_packet_length;
548     if (hci_is_le_connection(connection) && hci_stack->le_data_packets_length > 0){
549         max_acl_data_packet_length = hci_stack->le_data_packets_length;
550     }
551 
552     // testing: reduce buffer to minimum
553     // max_acl_data_packet_length = 52;
554 
555     log_debug("hci_send_acl_packet_fragments entered");
556 
557     int err;
558     // multiple packets could be send on a synchronous HCI transport
559     while (1){
560 
561         log_debug("hci_send_acl_packet_fragments loop entered");
562 
563         // get current data
564         const uint16_t acl_header_pos = hci_stack->acl_fragmentation_pos - 4;
565         int current_acl_data_packet_length = hci_stack->acl_fragmentation_total_size - hci_stack->acl_fragmentation_pos;
566         int more_fragments = 0;
567 
568         // if ACL packet is larger than Bluetooth packet buffer, only send max_acl_data_packet_length
569         if (current_acl_data_packet_length > max_acl_data_packet_length){
570             more_fragments = 1;
571             current_acl_data_packet_length = max_acl_data_packet_length;
572         }
573 
574         // copy handle_and_flags if not first fragment and update packet boundary flags to be 01 (continuing fragmnent)
575         if (acl_header_pos > 0){
576             uint16_t handle_and_flags = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
577             handle_and_flags = (handle_and_flags & 0xcfff) | (1 << 12);
578             little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos, handle_and_flags);
579         }
580 
581         // update header len
582         little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos + 2, current_acl_data_packet_length);
583 
584         // count packet
585         connection->num_acl_packets_sent++;
586         log_debug("hci_send_acl_packet_fragments loop before send (more fragments %d)", more_fragments);
587 
588         // update state for next fragment (if any) as "transport done" might be sent during send_packet already
589         if (more_fragments){
590             // update start of next fragment to send
591             hci_stack->acl_fragmentation_pos += current_acl_data_packet_length;
592         } else {
593             // done
594             hci_stack->acl_fragmentation_pos = 0;
595             hci_stack->acl_fragmentation_total_size = 0;
596         }
597 
598         // send packet
599         uint8_t * packet = &hci_stack->hci_packet_buffer[acl_header_pos];
600         const int size = current_acl_data_packet_length + 4;
601         hci_dump_packet(HCI_ACL_DATA_PACKET, 0, packet, size);
602         err = hci_stack->hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
603 
604         log_debug("hci_send_acl_packet_fragments loop after send (more fragments %d)", more_fragments);
605 
606         // done yet?
607         if (!more_fragments) break;
608 
609         // can send more?
610         if (!hci_can_send_prepared_acl_packet_now(connection->con_handle)) return err;
611     }
612 
613     log_debug("hci_send_acl_packet_fragments loop over");
614 
615     // release buffer now for synchronous transport
616     if (hci_transport_synchronous()){
617         hci_release_packet_buffer();
618         // notify upper stack that it might be possible to send again
619         uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
620         hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
621     }
622 
623     return err;
624 }
625 
626 // pre: caller has reserved the packet buffer
627 int hci_send_acl_packet_buffer(int size){
628 
629     // log_info("hci_send_acl_packet_buffer size %u", size);
630 
631     if (!hci_stack->hci_packet_buffer_reserved) {
632         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
633         return 0;
634     }
635 
636     uint8_t * packet = hci_stack->hci_packet_buffer;
637     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
638 
639     // check for free places on Bluetooth module
640     if (!hci_can_send_prepared_acl_packet_now(con_handle)) {
641         log_error("hci_send_acl_packet_buffer called but no free ACL buffers on controller");
642         hci_release_packet_buffer();
643         return BTSTACK_ACL_BUFFERS_FULL;
644     }
645 
646     hci_connection_t *connection = hci_connection_for_handle( con_handle);
647     if (!connection) {
648         log_error("hci_send_acl_packet_buffer called but no connection for handle 0x%04x", con_handle);
649         hci_release_packet_buffer();
650         return 0;
651     }
652 
653 #ifdef ENABLE_CLASSIC
654     hci_connection_timestamp(connection);
655 #endif
656 
657     // hci_dump_packet( HCI_ACL_DATA_PACKET, 0, packet, size);
658 
659     // setup data
660     hci_stack->acl_fragmentation_total_size = size;
661     hci_stack->acl_fragmentation_pos = 4;   // start of L2CAP packet
662 
663     return hci_send_acl_packet_fragments(connection);
664 }
665 
666 #ifdef ENABLE_CLASSIC
667 // pre: caller has reserved the packet buffer
668 int hci_send_sco_packet_buffer(int size){
669 
670     // log_info("hci_send_acl_packet_buffer size %u", size);
671 
672     if (!hci_stack->hci_packet_buffer_reserved) {
673         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
674         return 0;
675     }
676 
677     uint8_t * packet = hci_stack->hci_packet_buffer;
678 
679     // skip checks in loopback mode
680     if (!hci_stack->loopback_mode){
681         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);   // same for ACL and SCO
682 
683         // check for free places on Bluetooth module
684         if (!hci_can_send_prepared_sco_packet_now()) {
685             log_error("hci_send_sco_packet_buffer called but no free ACL buffers on controller");
686             hci_release_packet_buffer();
687             return BTSTACK_ACL_BUFFERS_FULL;
688         }
689 
690         // track send packet in connection struct
691         hci_connection_t *connection = hci_connection_for_handle( con_handle);
692         if (!connection) {
693             log_error("hci_send_sco_packet_buffer called but no connection for handle 0x%04x", con_handle);
694             hci_release_packet_buffer();
695             return 0;
696         }
697         connection->num_sco_packets_sent++;
698     }
699 
700     hci_dump_packet( HCI_SCO_DATA_PACKET, 0, packet, size);
701     int err = hci_stack->hci_transport->send_packet(HCI_SCO_DATA_PACKET, packet, size);
702 
703     if (hci_transport_synchronous()){
704         hci_release_packet_buffer();
705         // notify upper stack that it might be possible to send again
706         uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
707         hci_emit_event(&event[0], sizeof(event), 0);    // don't dump
708     }
709 
710     return err;
711 }
712 #endif
713 
714 static void acl_handler(uint8_t *packet, int size){
715 
716     // log_info("acl_handler: size %u", size);
717 
718     // get info
719     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
720     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
721     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
722     uint16_t acl_length         = READ_ACL_LENGTH(packet);
723 
724     // ignore non-registered handle
725     if (!conn){
726         log_error( "hci.c: acl_handler called with non-registered handle %u!" , con_handle);
727         return;
728     }
729 
730     // assert packet is complete
731     if (acl_length + 4 != size){
732         log_error("hci.c: acl_handler called with ACL packet of wrong size %d, expected %u => dropping packet", size, acl_length + 4);
733         return;
734     }
735 
736 #ifdef ENABLE_CLASSIC
737     // update idle timestamp
738     hci_connection_timestamp(conn);
739 #endif
740 
741 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
742     hci_stack->host_completed_packets = 1;
743     conn->num_packets_completed++;
744 #endif
745 
746     // handle different packet types
747     switch (acl_flags & 0x03) {
748 
749         case 0x01: // continuation fragment
750 
751             // sanity checks
752             if (conn->acl_recombination_pos == 0) {
753                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x", con_handle);
754                 return;
755             }
756             if (conn->acl_recombination_pos + acl_length > 4 + HCI_ACL_BUFFER_SIZE){
757                 log_error( "ACL Cont Fragment to large: combined packet %u > buffer size %u for handle 0x%02x",
758                     conn->acl_recombination_pos + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
759                 conn->acl_recombination_pos = 0;
760                 return;
761             }
762 
763             // append fragment payload (header already stored)
764             memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE + conn->acl_recombination_pos], &packet[4], acl_length );
765             conn->acl_recombination_pos += acl_length;
766 
767             // log_error( "ACL Cont Fragment: acl_len %u, combined_len %u, l2cap_len %u", acl_length,
768             //        conn->acl_recombination_pos, conn->acl_recombination_length);
769 
770             // forward complete L2CAP packet if complete.
771             if (conn->acl_recombination_pos >= conn->acl_recombination_length + 4 + 4){ // pos already incl. ACL header
772                 hci_emit_acl_packet(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], conn->acl_recombination_pos);
773                 // reset recombination buffer
774                 conn->acl_recombination_length = 0;
775                 conn->acl_recombination_pos = 0;
776             }
777             break;
778 
779         case 0x02: { // first fragment
780 
781             // sanity check
782             if (conn->acl_recombination_pos) {
783                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x, dropping stale fragments", con_handle);
784                 conn->acl_recombination_pos = 0;
785             }
786 
787             // peek into L2CAP packet!
788             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
789 
790             // log_info( "ACL First Fragment: acl_len %u, l2cap_len %u", acl_length, l2cap_length);
791 
792             // compare fragment size to L2CAP packet size
793             if (acl_length >= l2cap_length + 4){
794                 // forward fragment as L2CAP packet
795                 hci_emit_acl_packet(packet, acl_length + 4);
796             } else {
797 
798                 if (acl_length > HCI_ACL_BUFFER_SIZE){
799                     log_error( "ACL First Fragment to large: fragment %u > buffer size %u for handle 0x%02x",
800                         4 + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
801                     return;
802                 }
803 
804                 // store first fragment and tweak acl length for complete package
805                 memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], packet, acl_length + 4);
806                 conn->acl_recombination_pos    = acl_length + 4;
807                 conn->acl_recombination_length = l2cap_length;
808                 little_endian_store_16(conn->acl_recombination_buffer, HCI_INCOMING_PRE_BUFFER_SIZE + 2, l2cap_length +4);
809             }
810             break;
811 
812         }
813         default:
814             log_error( "hci.c: acl_handler called with invalid packet boundary flags %u", acl_flags & 0x03);
815             return;
816     }
817 
818     // execute main loop
819     hci_run();
820 }
821 
822 static void hci_shutdown_connection(hci_connection_t *conn){
823     log_info("Connection closed: handle 0x%x, %s", conn->con_handle, bd_addr_to_str(conn->address));
824 
825 #ifdef ENABLE_CLASSIC
826 #ifdef ENABLE_SCO_OVER_HCI
827     int addr_type = conn->address_type;
828 #endif
829 #endif
830 
831     btstack_run_loop_remove_timer(&conn->timeout);
832 
833     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
834     btstack_memory_hci_connection_free( conn );
835 
836     // now it's gone
837     hci_emit_nr_connections_changed();
838 
839 #ifdef ENABLE_CLASSIC
840 #ifdef ENABLE_SCO_OVER_HCI
841     // update SCO
842     if (addr_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
843         hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
844     }
845 #endif
846 #endif
847 }
848 
849 #ifdef ENABLE_CLASSIC
850 
851 static const uint16_t packet_type_sizes[] = {
852     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
853     HCI_ACL_DH1_SIZE, 0, 0, 0,
854     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
855     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
856 };
857 static const uint8_t  packet_type_feature_requirement_bit[] = {
858      0, // 3 slot packets
859      1, // 5 slot packets
860     25, // EDR 2 mpbs
861     26, // EDR 3 mbps
862     39, // 3 slot EDR packts
863     40, // 5 slot EDR packet
864 };
865 static const uint16_t packet_type_feature_packet_mask[] = {
866     0x0f00, // 3 slot packets
867     0xf000, // 5 slot packets
868     0x1102, // EDR 2 mpbs
869     0x2204, // EDR 3 mbps
870     0x0300, // 3 slot EDR packts
871     0x3000, // 5 slot EDR packet
872 };
873 
874 static uint16_t hci_acl_packet_types_for_buffer_size_and_local_features(uint16_t buffer_size, uint8_t * local_supported_features){
875     // enable packet types based on size
876     uint16_t packet_types = 0;
877     unsigned int i;
878     for (i=0;i<16;i++){
879         if (packet_type_sizes[i] == 0) continue;
880         if (packet_type_sizes[i] <= buffer_size){
881             packet_types |= 1 << i;
882         }
883     }
884     // disable packet types due to missing local supported features
885     for (i=0;i<sizeof(packet_type_feature_requirement_bit);i++){
886         unsigned int bit_idx = packet_type_feature_requirement_bit[i];
887         int feature_set = (local_supported_features[bit_idx >> 3] & (1<<(bit_idx & 7))) != 0;
888         if (feature_set) continue;
889         log_info("Features bit %02u is not set, removing packet types 0x%04x", bit_idx, packet_type_feature_packet_mask[i]);
890         packet_types &= ~packet_type_feature_packet_mask[i];
891     }
892     // flip bits for "may not be used"
893     packet_types ^= 0x3306;
894     return packet_types;
895 }
896 
897 uint16_t hci_usable_acl_packet_types(void){
898     return hci_stack->packet_types;
899 }
900 #endif
901 
902 uint8_t* hci_get_outgoing_packet_buffer(void){
903     // hci packet buffer is >= acl data packet length
904     return hci_stack->hci_packet_buffer;
905 }
906 
907 uint16_t hci_max_acl_data_packet_length(void){
908     return hci_stack->acl_data_packet_length;
909 }
910 
911 #ifdef ENABLE_CLASSIC
912 int hci_extended_sco_link_supported(void){
913     // No. 31, byte 3, bit 7
914     return (hci_stack->local_supported_features[3] & (1 << 7)) != 0;
915 }
916 #endif
917 
918 int hci_non_flushable_packet_boundary_flag_supported(void){
919     // No. 54, byte 6, bit 6
920     return (hci_stack->local_supported_features[6] & (1 << 6)) != 0;
921 }
922 
923 static int gap_ssp_supported(void){
924     // No. 51, byte 6, bit 3
925     return (hci_stack->local_supported_features[6] & (1 << 3)) != 0;
926 }
927 
928 static int hci_classic_supported(void){
929 #ifdef ENABLE_CLASSIC
930     // No. 37, byte 4, bit 5, = No BR/EDR Support
931     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
932 #else
933     return 0;
934 #endif
935 }
936 
937 static int hci_le_supported(void){
938 #ifdef ENABLE_BLE
939     // No. 37, byte 4, bit 6 = LE Supported (Controller)
940     return (hci_stack->local_supported_features[4] & (1 << 6)) != 0;
941 #else
942     return 0;
943 #endif
944 }
945 
946 #ifdef ENABLE_BLE
947 
948 /**
949  * @brief Get addr type and address used for LE in Advertisements, Scan Responses,
950  */
951 void gap_le_get_own_address(uint8_t * addr_type, bd_addr_t addr){
952     *addr_type = hci_stack->le_own_addr_type;
953     if (hci_stack->le_own_addr_type){
954         memcpy(addr, hci_stack->le_random_address, 6);
955     } else {
956         memcpy(addr, hci_stack->local_bd_addr, 6);
957     }
958 }
959 
960 #ifdef ENABLE_LE_CENTRAL
961 void le_handle_advertisement_report(uint8_t *packet, int size){
962 
963     UNUSED(size);
964 
965     int offset = 3;
966     int num_reports = packet[offset];
967     offset += 1;
968 
969     int i;
970     // log_info("HCI: handle adv report with num reports: %d", num_reports);
971     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
972     for (i=0; i<num_reports;i++){
973         uint8_t data_length = packet[offset + 8];
974         uint8_t event_size = 10 + data_length;
975         int pos = 0;
976         event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
977         event[pos++] = event_size;
978         memcpy(&event[pos], &packet[offset], 1+1+6); // event type + address type + address
979         offset += 8;
980         pos += 8;
981         event[pos++] = packet[offset + 1 + data_length]; // rssi
982         event[pos++] = packet[offset++]; //data_length;
983         memcpy(&event[pos], &packet[offset], data_length);
984         pos += data_length;
985         offset += data_length + 1; // rssi
986         hci_emit_event(event, pos, 1);
987     }
988 }
989 #endif
990 #endif
991 
992 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
993 
994 static uint32_t hci_transport_uart_get_main_baud_rate(void){
995     if (!hci_stack->config) return 0;
996     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
997     // Limit baud rate for Broadcom chipsets to 3 mbps
998     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION && baud_rate > 3000000){
999         baud_rate = 3000000;
1000     }
1001     return baud_rate;
1002 }
1003 
1004 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
1005     UNUSED(ds);
1006 
1007     switch (hci_stack->substate){
1008         case HCI_INIT_W4_SEND_RESET:
1009             log_info("Resend HCI Reset");
1010             hci_stack->substate = HCI_INIT_SEND_RESET;
1011             hci_stack->num_cmd_packets = 1;
1012             hci_run();
1013             break;
1014         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
1015             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
1016             if (hci_stack->hci_transport->reset_link){
1017                 hci_stack->hci_transport->reset_link();
1018             }
1019             // no break - explicit fallthrough to HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT
1020         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1021             log_info("Resend HCI Reset - CSR Warm Boot");
1022             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1023             hci_stack->num_cmd_packets = 1;
1024             hci_run();
1025             break;
1026         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1027             if (hci_stack->hci_transport->set_baudrate){
1028                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1029                 log_info("Local baud rate change to %"PRIu32"(timeout handler)", baud_rate);
1030                 hci_stack->hci_transport->set_baudrate(baud_rate);
1031             }
1032             // For CSR, HCI Reset is sent on new baud rate. Don't forget to reset link for H5/BCSP
1033             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
1034                 if (hci_stack->hci_transport->reset_link){
1035                     log_info("Link Reset");
1036                     hci_stack->hci_transport->reset_link();
1037                 }
1038                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1039                 hci_run();
1040             }
1041             break;
1042         case HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY:
1043             // otherwise continue
1044             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1045             hci_send_cmd(&hci_read_local_supported_commands);
1046             break;
1047         default:
1048             break;
1049     }
1050 }
1051 #endif
1052 
1053 static void hci_initializing_next_state(void){
1054     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
1055 }
1056 
1057 // assumption: hci_can_send_command_packet_now() == true
1058 static void hci_initializing_run(void){
1059     log_debug("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
1060     switch (hci_stack->substate){
1061         case HCI_INIT_SEND_RESET:
1062             hci_state_reset();
1063 
1064 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1065             // prepare reset if command complete not received in 100ms
1066             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1067             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1068             btstack_run_loop_add_timer(&hci_stack->timeout);
1069 #endif
1070             // send command
1071             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1072             hci_send_cmd(&hci_reset);
1073             break;
1074         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
1075             hci_send_cmd(&hci_read_local_version_information);
1076             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
1077             break;
1078         case HCI_INIT_SEND_READ_LOCAL_NAME:
1079             hci_send_cmd(&hci_read_local_name);
1080             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
1081             break;
1082 
1083 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1084         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1085             hci_state_reset();
1086             // prepare reset if command complete not received in 100ms
1087             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1088             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1089             btstack_run_loop_add_timer(&hci_stack->timeout);
1090             // send command
1091             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1092             hci_send_cmd(&hci_reset);
1093             break;
1094         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
1095             hci_state_reset();
1096             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1097             hci_send_cmd(&hci_reset);
1098             break;
1099         case HCI_INIT_SEND_BAUD_CHANGE: {
1100             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1101             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1102             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1103             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1104             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1105             // STLC25000D: baudrate change happens within 0.5 s after command was send,
1106             // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1107             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1108                 btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1109                 btstack_run_loop_add_timer(&hci_stack->timeout);
1110             }
1111             break;
1112         }
1113         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1114             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1115             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1116             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1117             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1118             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1119             break;
1120         }
1121         case HCI_INIT_CUSTOM_INIT:
1122             // Custom initialization
1123             if (hci_stack->chipset && hci_stack->chipset->next_command){
1124                 int valid_cmd = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1125                 if (valid_cmd){
1126                     int size = 3 + hci_stack->hci_packet_buffer[2];
1127                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1128                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1129                     switch (valid_cmd) {
1130                         case 1:
1131                         default:
1132                             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1133                             break;
1134                         case 2: // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1135                             log_info("CSR Warm Boot");
1136                             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1137                             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1138                             btstack_run_loop_add_timer(&hci_stack->timeout);
1139                             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO
1140                                 && hci_stack->config
1141                                 && hci_stack->chipset
1142                                 // && hci_stack->chipset->set_baudrate_command -- there's no such command
1143                                 && hci_stack->hci_transport->set_baudrate
1144                                 && hci_transport_uart_get_main_baud_rate()){
1145                                 hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1146                             } else {
1147                                hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1148                             }
1149                             break;
1150                     }
1151                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1152                     break;
1153                 }
1154                 log_info("Init script done");
1155 
1156                 // Init script download on Broadcom chipsets causes:
1157                 if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION){
1158                     // - baud rate to reset, restore UART baud rate if needed
1159                     int need_baud_change = hci_stack->config
1160                         && hci_stack->chipset
1161                         && hci_stack->chipset->set_baudrate_command
1162                         && hci_stack->hci_transport->set_baudrate
1163                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1164                     if (need_baud_change) {
1165                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1166                         log_info("Local baud rate change to %"PRIu32" after init script (bcm)", baud_rate);
1167                         hci_stack->hci_transport->set_baudrate(baud_rate);
1168                     }
1169 
1170                     // - RTS will raise during update, but manual RTS/CTS in WICED port on RedBear Duo cannot handle this
1171                     //   -> Work around: wait a few milliseconds here.
1172                     log_info("BCM delay after init script");
1173                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1174                     btstack_run_loop_set_timer(&hci_stack->timeout, 10);
1175                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1176                     btstack_run_loop_add_timer(&hci_stack->timeout);
1177                     break;
1178                 }
1179                         }
1180             // otherwise continue
1181             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1182             hci_send_cmd(&hci_read_local_supported_commands);
1183             break;
1184         case HCI_INIT_SET_BD_ADDR:
1185             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1186             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1187             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1188             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1189             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1190             break;
1191 #endif
1192 
1193         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1194             log_info("Resend hci_read_local_supported_commands after CSR Warm Boot double reset");
1195             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1196             hci_send_cmd(&hci_read_local_supported_commands);
1197             break;
1198         case HCI_INIT_READ_BD_ADDR:
1199             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1200             hci_send_cmd(&hci_read_bd_addr);
1201             break;
1202         case HCI_INIT_READ_BUFFER_SIZE:
1203             hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1204             hci_send_cmd(&hci_read_buffer_size);
1205             break;
1206         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1207             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1208             hci_send_cmd(&hci_read_local_supported_features);
1209             break;
1210 
1211 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1212         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1213             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1214             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1215             break;
1216         case HCI_INIT_HOST_BUFFER_SIZE:
1217             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1218             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1219                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1220             break;
1221 #endif
1222 
1223         case HCI_INIT_SET_EVENT_MASK:
1224             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1225             if (hci_le_supported()){
1226                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x3FFFFFFF);
1227             } else {
1228                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1229                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x1FFFFFFF);
1230             }
1231             break;
1232 
1233 #ifdef ENABLE_CLASSIC
1234         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1235             hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1236             hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1237             break;
1238         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1239             hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1240             hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1241             break;
1242         case HCI_INIT_WRITE_CLASS_OF_DEVICE:
1243             hci_stack->substate = HCI_INIT_W4_WRITE_CLASS_OF_DEVICE;
1244             hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1245             break;
1246         case HCI_INIT_WRITE_LOCAL_NAME:
1247             hci_stack->substate = HCI_INIT_W4_WRITE_LOCAL_NAME;
1248             if (hci_stack->local_name){
1249                 hci_send_cmd(&hci_write_local_name, hci_stack->local_name);
1250             } else {
1251                 char local_name[8+17+1];
1252                 // BTstack 11:22:33:44:55:66
1253                 memcpy(local_name, "BTstack ", 8);
1254                 memcpy(&local_name[8], bd_addr_to_str(hci_stack->local_bd_addr), 17);   // strlen(bd_addr_to_str(...)) = 17
1255                 local_name[8+17] = '\0';
1256                 log_info("---> Name %s", local_name);
1257                 hci_send_cmd(&hci_write_local_name, local_name);
1258             }
1259             break;
1260         case HCI_INIT_WRITE_EIR_DATA:
1261             hci_stack->substate = HCI_INIT_W4_WRITE_EIR_DATA;
1262             hci_send_cmd(&hci_write_extended_inquiry_response, 0, hci_stack->eir_data);
1263             break;
1264         case HCI_INIT_WRITE_INQUIRY_MODE:
1265             hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1266             hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1267             break;
1268         case HCI_INIT_WRITE_SCAN_ENABLE:
1269             hci_send_cmd(&hci_write_scan_enable, (hci_stack->connectable << 1) | hci_stack->discoverable); // page scan
1270             hci_stack->substate = HCI_INIT_W4_WRITE_SCAN_ENABLE;
1271             break;
1272         // only sent if ENABLE_SCO_OVER_HCI is defined
1273         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1274             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1275             hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1276             break;
1277         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1278             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1279             hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1280             break;
1281         // only sent if ENABLE_SCO_OVER_HCI and manufacturer is Broadcom
1282         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1283             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1284             log_info("BCM: Route SCO data via HCI transport");
1285             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1286             break;
1287 
1288 #endif
1289 #ifdef ENABLE_BLE
1290         // LE INIT
1291         case HCI_INIT_LE_READ_BUFFER_SIZE:
1292             hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1293             hci_send_cmd(&hci_le_read_buffer_size);
1294             break;
1295         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1296             // LE Supported Host = 1, Simultaneous Host = 0
1297             hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1298             hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1299             break;
1300         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1301             hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1302             hci_send_cmd(&hci_le_read_maximum_data_length);
1303             break;
1304         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1305             hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1306             // TODO: use values from read max data length
1307             hci_send_cmd(&hci_le_write_suggested_default_data_length, 251, 2120);
1308             break;
1309 #ifdef ENABLE_LE_CENTRAL
1310         case HCI_INIT_READ_WHITE_LIST_SIZE:
1311             hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1312             hci_send_cmd(&hci_le_read_white_list_size);
1313             break;
1314         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1315             // LE Scan Parameters: active scanning, 300 ms interval, 30 ms window, own address type, accept all advs
1316             hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1317             hci_send_cmd(&hci_le_set_scan_parameters, 1, 0x1e0, 0x30, hci_stack->le_own_addr_type, 0);
1318             break;
1319 #endif
1320 #endif
1321         default:
1322             return;
1323     }
1324 }
1325 
1326 static void hci_init_done(void){
1327     // done. tell the app
1328     log_info("hci_init_done -> HCI_STATE_WORKING");
1329     hci_stack->state = HCI_STATE_WORKING;
1330     hci_emit_state();
1331     hci_run();
1332 }
1333 
1334 static void hci_initializing_event_handler(uint8_t * packet, uint16_t size){
1335     UNUSED(size);
1336 
1337     uint8_t command_completed = 0;
1338 
1339     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1340         uint16_t opcode = little_endian_read_16(packet,3);
1341         if (opcode == hci_stack->last_cmd_opcode){
1342             command_completed = 1;
1343             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1344         } else {
1345             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1346         }
1347     }
1348 
1349     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1350         uint8_t  status = packet[2];
1351         uint16_t opcode = little_endian_read_16(packet,4);
1352         if (opcode == hci_stack->last_cmd_opcode){
1353             if (status){
1354                 command_completed = 1;
1355                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1356             } else {
1357                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1358             }
1359         } else {
1360             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1361         }
1362     }
1363 
1364 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1365 
1366     // Vendor == CSR
1367     if (hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT && hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC){
1368         // TODO: track actual command
1369         command_completed = 1;
1370     }
1371 
1372     // Vendor == Toshiba
1373     if (hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE && hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC){
1374         // TODO: track actual command
1375         command_completed = 1;
1376     }
1377 
1378     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1379     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1380     //
1381     // HCI Reset
1382     // Timeout 100 ms
1383     // HCI Reset
1384     // Command Complete Reset
1385     // HCI Read Local Version Information
1386     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1387     // hang...
1388     //
1389     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1390     if (!command_completed
1391             && hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE
1392             && hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION){
1393 
1394         uint16_t opcode = little_endian_read_16(packet,3);
1395         if (opcode == hci_reset.opcode){
1396             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1397             return;
1398         }
1399     }
1400 
1401     // CSR & H5
1402     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1403     if (!command_completed
1404             && hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE
1405             && hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS){
1406 
1407         uint16_t opcode = little_endian_read_16(packet,3);
1408         if (opcode == hci_reset.opcode){
1409             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1410             return;
1411         }
1412     }
1413 
1414     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1415     // fix: Correct substate and behave as command below
1416     if (command_completed){
1417         switch (hci_stack->substate){
1418             case HCI_INIT_SEND_RESET:
1419                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1420                 break;
1421             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1422                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1423                 break;
1424             default:
1425                 break;
1426         }
1427     }
1428 
1429 #endif
1430 
1431     if (!command_completed) return;
1432 
1433     int need_baud_change = 0;
1434     int need_addr_change = 0;
1435 
1436 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1437     need_baud_change = hci_stack->config
1438                         && hci_stack->chipset
1439                         && hci_stack->chipset->set_baudrate_command
1440                         && hci_stack->hci_transport->set_baudrate
1441                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1442 
1443     need_addr_change = hci_stack->custom_bd_addr_set
1444                         && hci_stack->chipset
1445                         && hci_stack->chipset->set_bd_addr_command;
1446 #endif
1447 
1448     switch(hci_stack->substate){
1449 
1450 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1451         case HCI_INIT_SEND_RESET:
1452             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1453             // fix: just correct substate and behave as command below
1454             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1455             btstack_run_loop_remove_timer(&hci_stack->timeout);
1456             break;
1457         case HCI_INIT_W4_SEND_RESET:
1458             btstack_run_loop_remove_timer(&hci_stack->timeout);
1459             break;
1460         case HCI_INIT_W4_SEND_READ_LOCAL_NAME:
1461             log_info("Received local name, need baud change %d", need_baud_change);
1462             if (need_baud_change){
1463                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE;
1464                 return;
1465             }
1466             // skip baud change
1467             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1468             return;
1469         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1470             // for STLC2500D, baud rate change already happened.
1471             // for others, baud rate gets changed now
1472             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1473                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1474                 log_info("Local baud rate change to %"PRIu32"(w4_send_baud_change)", baud_rate);
1475                 hci_stack->hci_transport->set_baudrate(baud_rate);
1476             }
1477             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1478             return;
1479         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1480             btstack_run_loop_remove_timer(&hci_stack->timeout);
1481             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1482             return;
1483         case HCI_INIT_W4_CUSTOM_INIT:
1484             // repeat custom init
1485             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1486             return;
1487 #else
1488         case HCI_INIT_W4_SEND_RESET:
1489             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1490             return ;
1491 #endif
1492 
1493         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1494             if (need_baud_change && hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION){
1495                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1496                 return;
1497             }
1498             if (need_addr_change){
1499                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1500                 return;
1501             }
1502             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1503             return;
1504 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1505         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1506             if (need_baud_change){
1507                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1508                 log_info("Local baud rate change to %"PRIu32"(w4_send_baud_change_bcm))", baud_rate);
1509                 hci_stack->hci_transport->set_baudrate(baud_rate);
1510             }
1511             if (need_addr_change){
1512                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1513                 return;
1514             }
1515             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1516             return;
1517         case HCI_INIT_W4_SET_BD_ADDR:
1518             // for STLC2500D, bd addr change only gets active after sending reset command
1519             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1520                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1521                 return;
1522             }
1523             // skipping st warm boot
1524             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1525             return;
1526         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
1527             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1528             return;
1529 #endif
1530         case HCI_INIT_W4_READ_BD_ADDR:
1531             // only read buffer size if supported
1532             if (hci_stack->local_supported_commands[0] & 0x01) {
1533                 hci_stack->substate = HCI_INIT_READ_BUFFER_SIZE;
1534                 return;
1535             }
1536             // skipping read buffer size
1537             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES;
1538             return;
1539         case HCI_INIT_W4_SET_EVENT_MASK:
1540             // skip Classic init commands for LE only chipsets
1541             if (!hci_classic_supported()){
1542 #ifdef ENABLE_BLE
1543                 if (hci_le_supported()){
1544                     hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE; // skip all classic command
1545                     return;
1546                 }
1547 #endif
1548                 log_error("Neither BR/EDR nor LE supported");
1549                 hci_init_done();
1550                 return;
1551             }
1552             if (!gap_ssp_supported()){
1553                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1554                 return;
1555             }
1556             break;
1557 #ifdef ENABLE_BLE
1558         case HCI_INIT_W4_LE_READ_BUFFER_SIZE:
1559             // skip write le host if not supported (e.g. on LE only EM9301)
1560             if (hci_stack->local_supported_commands[0] & 0x02) break;
1561 #ifdef ENABLE_LE_CENTRAL
1562             hci_stack->substate = HCI_INIT_LE_READ_MAX_DATA_LENGTH;
1563 #else
1564             hci_init_done();
1565 #endif
1566             return;
1567 #endif
1568         case HCI_INIT_W4_WRITE_LOCAL_NAME:
1569             // skip write eir data if no eir data set
1570             if (hci_stack->eir_data) break;
1571             hci_stack->substate = HCI_INIT_WRITE_INQUIRY_MODE;
1572             return;
1573 
1574 #ifdef ENABLE_SCO_OVER_HCI
1575         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1576             // skip write synchronous flow control if not supported
1577             if (hci_stack->local_supported_commands[0] & 0x04) break;
1578             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1579             // explicit fall through to reduce repetitions
1580 
1581         case HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1582             // skip write default erroneous data reporting if not supported
1583             if (hci_stack->local_supported_commands[0] & 0x08) break;
1584             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1585             // explicit fall through to reduce repetitions
1586 
1587         case HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1588             // skip bcm set sco pcm config on non-Broadcom chipsets
1589             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) break;
1590             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1591             // explicit fall through to reduce repetitions
1592 
1593         case HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT:
1594             if (!hci_le_supported()){
1595                 // SKIP LE init for Classic only configuration
1596                 hci_init_done();
1597                 return;
1598             }
1599             break;
1600 
1601 #else /* !ENABLE_SCO_OVER_HCI */
1602 
1603         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1604 #ifdef ENABLE_BLE
1605             if (hci_le_supported()){
1606                 hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE;
1607                 return;
1608             }
1609 #endif
1610             // SKIP LE init for Classic only configuration
1611             hci_init_done();
1612             return;
1613 #endif /* ENABLE_SCO_OVER_HCI */
1614 
1615         // Response to command before init done state -> init done
1616         case (HCI_INIT_DONE-1):
1617             hci_init_done();
1618             return;
1619 
1620         default:
1621             break;
1622     }
1623     hci_initializing_next_state();
1624 }
1625 
1626 static void event_handler(uint8_t *packet, int size){
1627 
1628     uint16_t event_length = packet[1];
1629 
1630     // assert packet is complete
1631     if (size != event_length + 2){
1632         log_error("hci.c: event_handler called with event packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
1633         return;
1634     }
1635 
1636     bd_addr_t addr;
1637     bd_addr_type_t addr_type;
1638     hci_con_handle_t handle;
1639     hci_connection_t * conn;
1640     int i;
1641 #ifdef ENABLE_CLASSIC
1642     uint8_t link_type;
1643 #endif
1644 
1645     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
1646 
1647     switch (hci_event_packet_get_type(packet)) {
1648 
1649         case HCI_EVENT_COMMAND_COMPLETE:
1650             // get num cmd packets - limit to 1 to reduce complexity
1651             hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
1652 
1653             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_name)){
1654                 if (packet[5]) break;
1655                 // terminate, name 248 chars
1656                 packet[6+248] = 0;
1657                 log_info("local name: %s", &packet[6]);
1658             }
1659             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_buffer_size)){
1660                 // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
1661                 if (hci_stack->state == HCI_STATE_INITIALIZING){
1662                     uint16_t acl_len = little_endian_read_16(packet, 6);
1663                     uint16_t sco_len = packet[8];
1664 
1665                     // determine usable ACL/SCO payload size
1666                     hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
1667                     hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
1668 
1669                     hci_stack->acl_packets_total_num  = little_endian_read_16(packet, 9);
1670                     hci_stack->sco_packets_total_num  = little_endian_read_16(packet, 11);
1671 
1672                     log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
1673                              acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
1674                              hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
1675                 }
1676             }
1677 #ifdef ENABLE_BLE
1678             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_buffer_size)){
1679                 hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
1680                 hci_stack->le_acl_packets_total_num  = packet[8];
1681                 // determine usable ACL payload size
1682                 if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
1683                     hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
1684                 }
1685                 log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
1686             }
1687             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_maximum_data_length)){
1688                 hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
1689                 hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
1690                 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);
1691             }
1692 #ifdef ENABLE_LE_CENTRAL
1693             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_white_list_size)){
1694                 hci_stack->le_whitelist_capacity = packet[6];
1695                 log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
1696             }
1697 #endif
1698 #endif
1699             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_bd_addr)) {
1700                 reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1],
1701 				hci_stack->local_bd_addr);
1702                 log_info("Local Address, Status: 0x%02x: Addr: %s",
1703                     packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE], bd_addr_to_str(hci_stack->local_bd_addr));
1704 #ifdef ENABLE_CLASSIC
1705                 if (hci_stack->link_key_db){
1706                     hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
1707                 }
1708 #endif
1709             }
1710 #ifdef ENABLE_CLASSIC
1711             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)){
1712                 hci_emit_discoverable_enabled(hci_stack->discoverable);
1713             }
1714             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_inquiry_cancel)){
1715                 if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
1716                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
1717                     uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
1718                     hci_emit_event(event, sizeof(event), 1);
1719                 }
1720             }
1721 #endif
1722 
1723             // Note: HCI init checks
1724             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_supported_features)){
1725                 memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 8);
1726 
1727 #ifdef ENABLE_CLASSIC
1728                 // determine usable ACL packet types based on host buffer size and supported features
1729                 hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
1730                 log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
1731 #endif
1732                 // Classic/LE
1733                 log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
1734             }
1735             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_version_information)){
1736                 // hci_stack->hci_version    = little_endian_read_16(packet, 4);
1737                 // hci_stack->hci_revision   = little_endian_read_16(packet, 6);
1738                 // hci_stack->lmp_version    = little_endian_read_16(packet, 8);
1739                 hci_stack->manufacturer   = little_endian_read_16(packet, 10);
1740                 // hci_stack->lmp_subversion = little_endian_read_16(packet, 12);
1741                 log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
1742             }
1743             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_supported_commands)){
1744                 hci_stack->local_supported_commands[0] =
1745                     (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+14] & 0x80) >> 7 |  // bit 0 = Octet 14, bit 7
1746                     (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+24] & 0x40) >> 5 |  // bit 1 = Octet 24, bit 6
1747                     (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+10] & 0x10) >> 2 |  // bit 2 = Octet 10, bit 4
1748                     (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+18] & 0x08)      |  // bit 3 = Octet 18, bit 3
1749                     (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+34] & 0x01) << 4 |  // bit 4 = Octet 34, bit 0
1750                     (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+35] & 0x08) << 2;   // bit 5 = Octet 35, bit 3
1751                     log_info("Local supported commands summary 0x%02x", hci_stack->local_supported_commands[0]);
1752             }
1753 #ifdef ENABLE_CLASSIC
1754             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_synchronous_flow_control_enable)){
1755                 if (packet[5] == 0){
1756                     hci_stack->synchronous_flow_control_enabled = 1;
1757                 }
1758             }
1759 #endif
1760             break;
1761 
1762         case HCI_EVENT_COMMAND_STATUS:
1763             // get num cmd packets - limit to 1 to reduce complexity
1764             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
1765             break;
1766 
1767         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
1768             int offset = 3;
1769             for (i=0; i<packet[2];i++){
1770                 handle = little_endian_read_16(packet, offset);
1771                 offset += 2;
1772                 uint16_t num_packets = little_endian_read_16(packet, offset);
1773                 offset += 2;
1774 
1775                 conn = hci_connection_for_handle(handle);
1776                 if (!conn){
1777                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
1778                     continue;
1779                 }
1780 
1781                 if (conn->address_type == BD_ADDR_TYPE_SCO){
1782 #ifdef ENABLE_CLASSIC
1783                     if (conn->num_sco_packets_sent >= num_packets){
1784                         conn->num_sco_packets_sent -= num_packets;
1785                     } else {
1786                         log_error("hci_number_completed_packets, more sco slots freed then sent.");
1787                         conn->num_sco_packets_sent = 0;
1788                     }
1789                     hci_notify_if_sco_can_send_now();
1790 #endif
1791                 } else {
1792                     if (conn->num_acl_packets_sent >= num_packets){
1793                         conn->num_acl_packets_sent -= num_packets;
1794                     } else {
1795                         log_error("hci_number_completed_packets, more acl slots freed then sent.");
1796                         conn->num_acl_packets_sent = 0;
1797                     }
1798                 }
1799                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_acl_packets_sent);
1800             }
1801             break;
1802         }
1803 
1804 #ifdef ENABLE_CLASSIC
1805         case HCI_EVENT_INQUIRY_COMPLETE:
1806             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
1807                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
1808                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
1809                 hci_emit_event(event, sizeof(event), 1);
1810             }
1811             break;
1812         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
1813             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
1814                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
1815             }
1816             break;
1817         case HCI_EVENT_CONNECTION_REQUEST:
1818             reverse_bd_addr(&packet[2], addr);
1819             // TODO: eval COD 8-10
1820             link_type = packet[11];
1821             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), link_type);
1822             addr_type = link_type == 1 ? BD_ADDR_TYPE_CLASSIC : BD_ADDR_TYPE_SCO;
1823             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
1824             if (!conn) {
1825                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
1826             }
1827             if (!conn) {
1828                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
1829                 hci_stack->decline_reason = 0x0d;
1830                 bd_addr_copy(hci_stack->decline_addr, addr);
1831                 break;
1832             }
1833             conn->role  = HCI_ROLE_SLAVE;
1834             conn->state = RECEIVED_CONNECTION_REQUEST;
1835             // store info about eSCO
1836             if (link_type == 0x02){
1837                 conn->remote_supported_feature_eSCO = 1;
1838             }
1839             hci_run();
1840             break;
1841 
1842         case HCI_EVENT_CONNECTION_COMPLETE:
1843             // Connection management
1844             reverse_bd_addr(&packet[5], addr);
1845             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
1846             addr_type = BD_ADDR_TYPE_CLASSIC;
1847             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
1848             if (conn) {
1849                 if (!packet[2]){
1850                     conn->state = OPEN;
1851                     conn->con_handle = little_endian_read_16(packet, 3);
1852                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES;
1853 
1854                     // restart timer
1855                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
1856                     btstack_run_loop_add_timer(&conn->timeout);
1857 
1858                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
1859 
1860                     hci_emit_nr_connections_changed();
1861                 } else {
1862                     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
1863                     uint8_t status = packet[2];
1864                     bd_addr_t bd_address;
1865                     memcpy(&bd_address, conn->address, 6);
1866 
1867                     // connection failed, remove entry
1868                     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1869                     btstack_memory_hci_connection_free( conn );
1870 
1871                     // notify client if dedicated bonding
1872                     if (notify_dedicated_bonding_failed){
1873                         log_info("hci notify_dedicated_bonding_failed");
1874                         hci_emit_dedicated_bonding_result(bd_address, status);
1875                     }
1876 
1877                     // if authentication error, also delete link key
1878                     if (packet[2] == 0x05) {
1879                         gap_drop_link_key_for_bd_addr(addr);
1880                     }
1881                 }
1882             }
1883             break;
1884 
1885         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
1886             reverse_bd_addr(&packet[5], addr);
1887             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
1888             if (packet[2]){
1889                 // connection failed
1890                 break;
1891             }
1892             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
1893             if (!conn) {
1894                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
1895             }
1896             if (!conn) {
1897                 break;
1898             }
1899             conn->state = OPEN;
1900             conn->con_handle = little_endian_read_16(packet, 3);
1901 
1902 #ifdef ENABLE_SCO_OVER_HCI
1903             // update SCO
1904             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
1905                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
1906             }
1907 #endif
1908             break;
1909 
1910         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
1911             handle = little_endian_read_16(packet, 3);
1912             conn = hci_connection_for_handle(handle);
1913             if (!conn) break;
1914             if (!packet[2]){
1915                 uint8_t * features = &packet[5];
1916                 if (features[6] & (1 << 3)){
1917                     conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP;
1918                 }
1919                 if (features[3] & (1<<7)){
1920                     conn->remote_supported_feature_eSCO = 1;
1921                 }
1922             }
1923             conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
1924             log_info("HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE, bonding flags %x, eSCO %u", conn->bonding_flags, conn->remote_supported_feature_eSCO);
1925             if (conn->bonding_flags & BONDING_DEDICATED){
1926                 conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
1927             }
1928             break;
1929 
1930         case HCI_EVENT_LINK_KEY_REQUEST:
1931             log_info("HCI_EVENT_LINK_KEY_REQUEST");
1932             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_REQUEST);
1933             // non-bondable mode: link key negative reply will be sent by HANDLE_LINK_KEY_REQUEST
1934             if (hci_stack->bondable && !hci_stack->link_key_db) break;
1935             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], HANDLE_LINK_KEY_REQUEST);
1936             hci_run();
1937             // request handled by hci_run() as HANDLE_LINK_KEY_REQUEST gets set
1938             return;
1939 
1940         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
1941             reverse_bd_addr(&packet[2], addr);
1942             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
1943             if (!conn) break;
1944             conn->authentication_flags |= RECV_LINK_KEY_NOTIFICATION;
1945             link_key_type_t link_key_type = (link_key_type_t)packet[24];
1946             // Change Connection Encryption keeps link key type
1947             if (link_key_type != CHANGED_COMBINATION_KEY){
1948                 conn->link_key_type = link_key_type;
1949             }
1950             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
1951             // still forward event to allow dismiss of pairing dialog
1952             break;
1953         }
1954 
1955         case HCI_EVENT_PIN_CODE_REQUEST:
1956             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], LEGACY_PAIRING_ACTIVE);
1957             // non-bondable mode: pin code negative reply will be sent
1958             if (!hci_stack->bondable){
1959                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], DENY_PIN_CODE_REQUEST);
1960                 hci_run();
1961                 return;
1962             }
1963             // PIN CODE REQUEST means the link key request didn't succee -> delete stored link key
1964             if (!hci_stack->link_key_db) break;
1965             hci_event_pin_code_request_get_bd_addr(packet, addr);
1966             hci_stack->link_key_db->delete_link_key(addr);
1967             break;
1968 
1969         case HCI_EVENT_IO_CAPABILITY_REQUEST:
1970             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_IO_CAPABILITIES_REQUEST);
1971             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_IO_CAPABILITIES_REPLY);
1972             break;
1973 
1974         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
1975             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
1976             if (!hci_stack->ssp_auto_accept) break;
1977             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_CONFIRM_REPLY);
1978             break;
1979 
1980         case HCI_EVENT_USER_PASSKEY_REQUEST:
1981             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
1982             if (!hci_stack->ssp_auto_accept) break;
1983             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_PASSKEY_REPLY);
1984             break;
1985 #endif
1986 
1987         case HCI_EVENT_ENCRYPTION_CHANGE:
1988             handle = little_endian_read_16(packet, 3);
1989             conn = hci_connection_for_handle(handle);
1990             if (!conn) break;
1991             if (packet[2] == 0) {
1992                 if (packet[5]){
1993                     conn->authentication_flags |= CONNECTION_ENCRYPTED;
1994                 } else {
1995                     conn->authentication_flags &= ~CONNECTION_ENCRYPTED;
1996                 }
1997             }
1998 #ifdef ENABLE_CLASSIC
1999             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2000 #endif
2001             break;
2002 
2003 #ifdef ENABLE_CLASSIC
2004         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
2005             handle = little_endian_read_16(packet, 3);
2006             conn = hci_connection_for_handle(handle);
2007             if (!conn) break;
2008 
2009             // dedicated bonding: send result and disconnect
2010             if (conn->bonding_flags & BONDING_DEDICATED){
2011                 conn->bonding_flags &= ~BONDING_DEDICATED;
2012                 conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
2013                 conn->bonding_status = packet[2];
2014                 break;
2015             }
2016 
2017             if (packet[2] == 0 && gap_security_level_for_link_key_type(conn->link_key_type) >= conn->requested_security_level){
2018                 // link key sufficient for requested security
2019                 conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
2020                 break;
2021             }
2022             // not enough
2023             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2024             break;
2025 #endif
2026 
2027         // HCI_EVENT_DISCONNECTION_COMPLETE
2028         // has been split, to first notify stack before shutting connection down
2029         // see end of function, too.
2030         case HCI_EVENT_DISCONNECTION_COMPLETE:
2031             if (packet[2]) break;   // status != 0
2032             handle = little_endian_read_16(packet, 3);
2033             // drop outgoing ACL fragments if it is for closed connection
2034             if (hci_stack->acl_fragmentation_total_size > 0) {
2035                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
2036                     log_info("hci: drop fragmented ACL data for closed connection");
2037                      hci_stack->acl_fragmentation_total_size = 0;
2038                      hci_stack->acl_fragmentation_pos = 0;
2039                 }
2040             }
2041 
2042             // re-enable advertisements for le connections if active
2043             conn = hci_connection_for_handle(handle);
2044             if (!conn) break;
2045 #ifdef ENABLE_BLE
2046 #ifdef ENABLE_LE_PERIPHERAL
2047             if (hci_is_le_connection(conn) && hci_stack->le_advertisements_enabled){
2048                 hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
2049             }
2050 #endif
2051 #endif
2052             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
2053             break;
2054 
2055         case HCI_EVENT_HARDWARE_ERROR:
2056             log_error("Hardware Error: 0x%02x", packet[2]);
2057             if (hci_stack->hardware_error_callback){
2058                 (*hci_stack->hardware_error_callback)(packet[2]);
2059             } else {
2060                 // if no special requests, just reboot stack
2061                 hci_power_control_off();
2062                 hci_power_control_on();
2063             }
2064             break;
2065 
2066 #ifdef ENABLE_CLASSIC
2067         case HCI_EVENT_ROLE_CHANGE:
2068             if (packet[2]) break;   // status != 0
2069             handle = little_endian_read_16(packet, 3);
2070             conn = hci_connection_for_handle(handle);
2071             if (!conn) break;       // no conn
2072             conn->role = packet[9];
2073             break;
2074 #endif
2075 
2076         case HCI_EVENT_TRANSPORT_PACKET_SENT:
2077             // release packet buffer only for asynchronous transport and if there are not further fragements
2078             if (hci_transport_synchronous()) {
2079                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
2080                 return; // instead of break: to avoid re-entering hci_run()
2081             }
2082             if (hci_stack->acl_fragmentation_total_size) break;
2083             hci_release_packet_buffer();
2084 
2085             // L2CAP receives this event via the hci_emit_event below
2086 
2087 #ifdef ENABLE_CLASSIC
2088             // For SCO, we do the can_send_now_check here
2089             hci_notify_if_sco_can_send_now();
2090 #endif
2091             break;
2092 
2093 #ifdef ENABLE_CLASSIC
2094         case HCI_EVENT_SCO_CAN_SEND_NOW:
2095             // For SCO, we do the can_send_now_check here
2096             hci_notify_if_sco_can_send_now();
2097             return;
2098 
2099         // explode inquriy results for easier consumption
2100         case HCI_EVENT_INQUIRY_RESULT:
2101         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
2102         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
2103             gap_inquiry_explode(packet);
2104             break;
2105 #endif
2106 
2107 #ifdef ENABLE_BLE
2108         case HCI_EVENT_LE_META:
2109             switch (packet[2]){
2110 #ifdef ENABLE_LE_CENTRAL
2111                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
2112                     // log_info("advertising report received");
2113                     if (hci_stack->le_scanning_state != LE_SCANNING) break;
2114                     le_handle_advertisement_report(packet, size);
2115                     break;
2116 #endif
2117                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
2118                     // Connection management
2119                     reverse_bd_addr(&packet[8], addr);
2120                     addr_type = (bd_addr_type_t)packet[7];
2121                     log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2122                     conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2123 #ifdef ENABLE_LE_CENTRAL
2124                     // if auto-connect, remove from whitelist in both roles
2125                     if (hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST){
2126                         hci_remove_from_whitelist(addr_type, addr);
2127                     }
2128                     // handle error: error is reported only to the initiator -> outgoing connection
2129                     if (packet[3]){
2130                         // outgoing connection establishment is done
2131                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2132                         // remove entry
2133                         if (conn){
2134                             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2135                             btstack_memory_hci_connection_free( conn );
2136                         }
2137                         break;
2138                     }
2139 #endif
2140                     // on success, both hosts receive connection complete event
2141                     if (packet[6] == HCI_ROLE_MASTER){
2142 #ifdef ENABLE_LE_CENTRAL
2143                         // if we're master, it was an outgoing connection and we're done with it
2144                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2145 #endif
2146                     } else {
2147 #ifdef ENABLE_LE_PERIPHERAL
2148                         // if we're slave, it was an incoming connection, advertisements have stopped
2149                         hci_stack->le_advertisements_active = 0;
2150                         // try to re-enable them
2151                         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
2152 #endif
2153                     }
2154                     // LE connections are auto-accepted, so just create a connection if there isn't one already
2155                     if (!conn){
2156                         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2157                     }
2158                     // no memory, sorry.
2159                     if (!conn){
2160                         break;
2161                     }
2162 
2163                     conn->state = OPEN;
2164                     conn->role  = packet[6];
2165                     conn->con_handle = little_endian_read_16(packet, 4);
2166 
2167                     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2168 
2169                     // restart timer
2170                     // btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2171                     // btstack_run_loop_add_timer(&conn->timeout);
2172 
2173                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2174 
2175                     hci_emit_nr_connections_changed();
2176                     break;
2177 
2178             // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
2179 
2180                 default:
2181                     break;
2182             }
2183             break;
2184 #endif
2185         default:
2186             break;
2187     }
2188 
2189     // handle BT initialization
2190     if (hci_stack->state == HCI_STATE_INITIALIZING){
2191         hci_initializing_event_handler(packet, size);
2192     }
2193 
2194     // help with BT sleep
2195     if (hci_stack->state == HCI_STATE_FALLING_ASLEEP
2196         && hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE
2197         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)){
2198         hci_initializing_next_state();
2199     }
2200 
2201     // notify upper stack
2202 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
2203 
2204     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
2205     if (hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE){
2206         if (!packet[2]){
2207             handle = little_endian_read_16(packet, 3);
2208             hci_connection_t * aConn = hci_connection_for_handle(handle);
2209             if (aConn) {
2210                 uint8_t status = aConn->bonding_status;
2211                 uint16_t flags = aConn->bonding_flags;
2212                 bd_addr_t bd_address;
2213                 memcpy(&bd_address, aConn->address, 6);
2214                 hci_shutdown_connection(aConn);
2215                 // connection struct is gone, don't access anymore
2216                 if (flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
2217                     hci_emit_dedicated_bonding_result(bd_address, status);
2218                 }
2219             }
2220         }
2221     }
2222 
2223 	// execute main loop
2224 	hci_run();
2225 }
2226 
2227 #ifdef ENABLE_CLASSIC
2228 static void sco_handler(uint8_t * packet, uint16_t size){
2229     if (!hci_stack->sco_packet_handler) return;
2230     hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
2231 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
2232     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
2233     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
2234     if (conn){
2235         conn->num_packets_completed++;
2236         hci_stack->host_completed_packets = 1;
2237         hci_run();
2238     }
2239 #endif
2240 }
2241 #endif
2242 
2243 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
2244     hci_dump_packet(packet_type, 1, packet, size);
2245     switch (packet_type) {
2246         case HCI_EVENT_PACKET:
2247             event_handler(packet, size);
2248             break;
2249         case HCI_ACL_DATA_PACKET:
2250             acl_handler(packet, size);
2251             break;
2252 #ifdef ENABLE_CLASSIC
2253         case HCI_SCO_DATA_PACKET:
2254             sco_handler(packet, size);
2255             break;
2256 #endif
2257         default:
2258             break;
2259     }
2260 }
2261 
2262 /**
2263  * @brief Add event packet handler.
2264  */
2265 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
2266     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
2267 }
2268 
2269 
2270 /** Register HCI packet handlers */
2271 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
2272     hci_stack->acl_packet_handler = handler;
2273 }
2274 
2275 #ifdef ENABLE_CLASSIC
2276 /**
2277  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
2278  */
2279 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
2280     hci_stack->sco_packet_handler = handler;
2281 }
2282 #endif
2283 
2284 static void hci_state_reset(void){
2285     // no connections yet
2286     hci_stack->connections = NULL;
2287 
2288     // keep discoverable/connectable as this has been requested by the client(s)
2289     // hci_stack->discoverable = 0;
2290     // hci_stack->connectable = 0;
2291     // hci_stack->bondable = 1;
2292     // hci_stack->own_addr_type = 0;
2293 
2294     // buffer is free
2295     hci_stack->hci_packet_buffer_reserved = 0;
2296 
2297     // no pending cmds
2298     hci_stack->decline_reason = 0;
2299     hci_stack->new_scan_enable_value = 0xff;
2300 
2301     // LE
2302 #ifdef ENABLE_BLE
2303     memset(hci_stack->le_random_address, 0, 6);
2304     hci_stack->le_random_address_set = 0;
2305 #endif
2306 #ifdef ENABLE_LE_CENTRAL
2307     hci_stack->le_scanning_state = LE_SCAN_IDLE;
2308     hci_stack->le_scan_type = 0xff;
2309     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2310     hci_stack->le_whitelist = 0;
2311     hci_stack->le_whitelist_capacity = 0;
2312 
2313     // connection parameter to use for outgoing connections
2314     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
2315     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
2316     hci_stack->le_connection_latency      = 4;         // 4
2317     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
2318     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
2319     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
2320 #endif
2321 
2322     // connection parameter range used to answer connection parameter update requests in l2cap
2323     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
2324     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
2325     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
2326     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
2327     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
2328     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
2329 }
2330 
2331 #ifdef ENABLE_CLASSIC
2332 /**
2333  * @brief Configure Bluetooth hardware control. Has to be called before power on.
2334  */
2335 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
2336     // store and open remote device db
2337     hci_stack->link_key_db = link_key_db;
2338     if (hci_stack->link_key_db) {
2339         hci_stack->link_key_db->open();
2340     }
2341 }
2342 #endif
2343 
2344 void hci_init(const hci_transport_t *transport, const void *config){
2345 
2346 #ifdef HAVE_MALLOC
2347     if (!hci_stack) {
2348         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
2349     }
2350 #else
2351     hci_stack = &hci_stack_static;
2352 #endif
2353     memset(hci_stack, 0, sizeof(hci_stack_t));
2354 
2355     // reference to use transport layer implementation
2356     hci_stack->hci_transport = transport;
2357 
2358     // reference to used config
2359     hci_stack->config = config;
2360 
2361     // setup pointer for outgoing packet buffer
2362     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
2363 
2364     // max acl payload size defined in config.h
2365     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
2366 
2367     // register packet handlers with transport
2368     transport->register_packet_handler(&packet_handler);
2369 
2370     hci_stack->state = HCI_STATE_OFF;
2371 
2372     // class of device
2373     hci_stack->class_of_device = 0x007a020c; // Smartphone
2374 
2375     // bondable by default
2376     hci_stack->bondable = 1;
2377 
2378     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
2379     hci_stack->ssp_enable = 1;
2380     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
2381     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
2382     hci_stack->ssp_auto_accept = 1;
2383 
2384     // voice setting - signed 16 bit pcm data with CVSD over the air
2385     hci_stack->sco_voice_setting = 0x60;
2386 
2387     hci_state_reset();
2388 }
2389 
2390 /**
2391  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
2392  */
2393 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
2394     hci_stack->chipset = chipset_driver;
2395 
2396     // reset chipset driver - init is also called on power_up
2397     if (hci_stack->chipset && hci_stack->chipset->init){
2398         hci_stack->chipset->init(hci_stack->config);
2399     }
2400 }
2401 
2402 /**
2403  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
2404  */
2405 void hci_set_control(const btstack_control_t *hardware_control){
2406     // references to used control implementation
2407     hci_stack->control = hardware_control;
2408     // init with transport config
2409     hardware_control->init(hci_stack->config);
2410 }
2411 
2412 void hci_close(void){
2413     // close remote device db
2414     if (hci_stack->link_key_db) {
2415         hci_stack->link_key_db->close();
2416     }
2417 
2418     btstack_linked_list_iterator_t lit;
2419     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
2420     while (btstack_linked_list_iterator_has_next(&lit)){
2421         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
2422         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
2423         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
2424         hci_shutdown_connection(connection);
2425     }
2426 
2427     hci_power_control(HCI_POWER_OFF);
2428 
2429 #ifdef HAVE_MALLOC
2430     free(hci_stack);
2431 #endif
2432     hci_stack = NULL;
2433 }
2434 
2435 #ifdef ENABLE_CLASSIC
2436 void gap_set_class_of_device(uint32_t class_of_device){
2437     hci_stack->class_of_device = class_of_device;
2438 }
2439 
2440 void hci_disable_l2cap_timeout_check(void){
2441     disable_l2cap_timeouts = 1;
2442 }
2443 #endif
2444 
2445 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
2446 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
2447 void hci_set_bd_addr(bd_addr_t addr){
2448     memcpy(hci_stack->custom_bd_addr, addr, 6);
2449     hci_stack->custom_bd_addr_set = 1;
2450 }
2451 #endif
2452 
2453 // State-Module-Driver overview
2454 // state                    module  low-level
2455 // HCI_STATE_OFF             off      close
2456 // HCI_STATE_INITIALIZING,   on       open
2457 // HCI_STATE_WORKING,        on       open
2458 // HCI_STATE_HALTING,        on       open
2459 // HCI_STATE_SLEEPING,    off/sleep   close
2460 // HCI_STATE_FALLING_ASLEEP  on       open
2461 
2462 static int hci_power_control_on(void){
2463 
2464     // power on
2465     int err = 0;
2466     if (hci_stack->control && hci_stack->control->on){
2467         err = (*hci_stack->control->on)();
2468     }
2469     if (err){
2470         log_error( "POWER_ON failed");
2471         hci_emit_hci_open_failed();
2472         return err;
2473     }
2474 
2475     // int chipset driver
2476     if (hci_stack->chipset && hci_stack->chipset->init){
2477         hci_stack->chipset->init(hci_stack->config);
2478     }
2479 
2480     // init transport
2481     if (hci_stack->hci_transport->init){
2482         hci_stack->hci_transport->init(hci_stack->config);
2483     }
2484 
2485     // open transport
2486     err = hci_stack->hci_transport->open();
2487     if (err){
2488         log_error( "HCI_INIT failed, turning Bluetooth off again");
2489         if (hci_stack->control && hci_stack->control->off){
2490             (*hci_stack->control->off)();
2491         }
2492         hci_emit_hci_open_failed();
2493         return err;
2494     }
2495     return 0;
2496 }
2497 
2498 static void hci_power_control_off(void){
2499 
2500     log_info("hci_power_control_off");
2501 
2502     // close low-level device
2503     hci_stack->hci_transport->close();
2504 
2505     log_info("hci_power_control_off - hci_transport closed");
2506 
2507     // power off
2508     if (hci_stack->control && hci_stack->control->off){
2509         (*hci_stack->control->off)();
2510     }
2511 
2512     log_info("hci_power_control_off - control closed");
2513 
2514     hci_stack->state = HCI_STATE_OFF;
2515 }
2516 
2517 static void hci_power_control_sleep(void){
2518 
2519     log_info("hci_power_control_sleep");
2520 
2521 #if 0
2522     // don't close serial port during sleep
2523 
2524     // close low-level device
2525     hci_stack->hci_transport->close(hci_stack->config);
2526 #endif
2527 
2528     // sleep mode
2529     if (hci_stack->control && hci_stack->control->sleep){
2530         (*hci_stack->control->sleep)();
2531     }
2532 
2533     hci_stack->state = HCI_STATE_SLEEPING;
2534 }
2535 
2536 static int hci_power_control_wake(void){
2537 
2538     log_info("hci_power_control_wake");
2539 
2540     // wake on
2541     if (hci_stack->control && hci_stack->control->wake){
2542         (*hci_stack->control->wake)();
2543     }
2544 
2545 #if 0
2546     // open low-level device
2547     int err = hci_stack->hci_transport->open(hci_stack->config);
2548     if (err){
2549         log_error( "HCI_INIT failed, turning Bluetooth off again");
2550         if (hci_stack->control && hci_stack->control->off){
2551             (*hci_stack->control->off)();
2552         }
2553         hci_emit_hci_open_failed();
2554         return err;
2555     }
2556 #endif
2557 
2558     return 0;
2559 }
2560 
2561 static void hci_power_transition_to_initializing(void){
2562     // set up state machine
2563     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
2564     hci_stack->hci_packet_buffer_reserved = 0;
2565     hci_stack->state = HCI_STATE_INITIALIZING;
2566     hci_stack->substate = HCI_INIT_SEND_RESET;
2567 }
2568 
2569 int hci_power_control(HCI_POWER_MODE power_mode){
2570 
2571     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
2572 
2573     int err = 0;
2574     switch (hci_stack->state){
2575 
2576         case HCI_STATE_OFF:
2577             switch (power_mode){
2578                 case HCI_POWER_ON:
2579                     err = hci_power_control_on();
2580                     if (err) {
2581                         log_error("hci_power_control_on() error %d", err);
2582                         return err;
2583                     }
2584                     hci_power_transition_to_initializing();
2585                     break;
2586                 case HCI_POWER_OFF:
2587                     // do nothing
2588                     break;
2589                 case HCI_POWER_SLEEP:
2590                     // do nothing (with SLEEP == OFF)
2591                     break;
2592             }
2593             break;
2594 
2595         case HCI_STATE_INITIALIZING:
2596             switch (power_mode){
2597                 case HCI_POWER_ON:
2598                     // do nothing
2599                     break;
2600                 case HCI_POWER_OFF:
2601                     // no connections yet, just turn it off
2602                     hci_power_control_off();
2603                     break;
2604                 case HCI_POWER_SLEEP:
2605                     // no connections yet, just turn it off
2606                     hci_power_control_sleep();
2607                     break;
2608             }
2609             break;
2610 
2611         case HCI_STATE_WORKING:
2612             switch (power_mode){
2613                 case HCI_POWER_ON:
2614                     // do nothing
2615                     break;
2616                 case HCI_POWER_OFF:
2617                     // see hci_run
2618                     hci_stack->state = HCI_STATE_HALTING;
2619                     break;
2620                 case HCI_POWER_SLEEP:
2621                     // see hci_run
2622                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
2623                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
2624                     break;
2625             }
2626             break;
2627 
2628         case HCI_STATE_HALTING:
2629             switch (power_mode){
2630                 case HCI_POWER_ON:
2631                     hci_power_transition_to_initializing();
2632                     break;
2633                 case HCI_POWER_OFF:
2634                     // do nothing
2635                     break;
2636                 case HCI_POWER_SLEEP:
2637                     // see hci_run
2638                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
2639                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
2640                     break;
2641             }
2642             break;
2643 
2644         case HCI_STATE_FALLING_ASLEEP:
2645             switch (power_mode){
2646                 case HCI_POWER_ON:
2647 
2648 #ifdef HAVE_PLATFORM_IPHONE_OS
2649                     // nothing to do, if H4 supports power management
2650                     if (btstack_control_iphone_power_management_enabled()){
2651                         hci_stack->state = HCI_STATE_INITIALIZING;
2652                         hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;   // init after sleep
2653                         break;
2654                     }
2655 #endif
2656                     hci_power_transition_to_initializing();
2657                     break;
2658                 case HCI_POWER_OFF:
2659                     // see hci_run
2660                     hci_stack->state = HCI_STATE_HALTING;
2661                     break;
2662                 case HCI_POWER_SLEEP:
2663                     // do nothing
2664                     break;
2665             }
2666             break;
2667 
2668         case HCI_STATE_SLEEPING:
2669             switch (power_mode){
2670                 case HCI_POWER_ON:
2671 
2672 #ifdef HAVE_PLATFORM_IPHONE_OS
2673                     // nothing to do, if H4 supports power management
2674                     if (btstack_control_iphone_power_management_enabled()){
2675                         hci_stack->state = HCI_STATE_INITIALIZING;
2676                         hci_stack->substate = HCI_INIT_AFTER_SLEEP;
2677                         hci_update_scan_enable();
2678                         break;
2679                     }
2680 #endif
2681                     err = hci_power_control_wake();
2682                     if (err) return err;
2683                     hci_power_transition_to_initializing();
2684                     break;
2685                 case HCI_POWER_OFF:
2686                     hci_stack->state = HCI_STATE_HALTING;
2687                     break;
2688                 case HCI_POWER_SLEEP:
2689                     // do nothing
2690                     break;
2691             }
2692             break;
2693     }
2694 
2695     // create internal event
2696 	hci_emit_state();
2697 
2698 	// trigger next/first action
2699 	hci_run();
2700 
2701     return 0;
2702 }
2703 
2704 
2705 #ifdef ENABLE_CLASSIC
2706 
2707 static void hci_update_scan_enable(void){
2708     // 2 = page scan, 1 = inq scan
2709     hci_stack->new_scan_enable_value  = hci_stack->connectable << 1 | hci_stack->discoverable;
2710     hci_run();
2711 }
2712 
2713 void gap_discoverable_control(uint8_t enable){
2714     if (enable) enable = 1; // normalize argument
2715 
2716     if (hci_stack->discoverable == enable){
2717         hci_emit_discoverable_enabled(hci_stack->discoverable);
2718         return;
2719     }
2720 
2721     hci_stack->discoverable = enable;
2722     hci_update_scan_enable();
2723 }
2724 
2725 void gap_connectable_control(uint8_t enable){
2726     if (enable) enable = 1; // normalize argument
2727 
2728     // don't emit event
2729     if (hci_stack->connectable == enable) return;
2730 
2731     hci_stack->connectable = enable;
2732     hci_update_scan_enable();
2733 }
2734 #endif
2735 
2736 void gap_local_bd_addr(bd_addr_t address_buffer){
2737     memcpy(address_buffer, hci_stack->local_bd_addr, 6);
2738 }
2739 
2740 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
2741 static void hci_host_num_completed_packets(void){
2742 
2743     // create packet manually as arrays are not supported and num_commands should not get reduced
2744     hci_reserve_packet_buffer();
2745     uint8_t * packet = hci_get_outgoing_packet_buffer();
2746 
2747     uint16_t size = 0;
2748     uint16_t num_handles = 0;
2749     packet[size++] = 0x35;
2750     packet[size++] = 0x0c;
2751     size++;  // skip param len
2752     size++;  // skip num handles
2753 
2754     // add { handle, packets } entries
2755     btstack_linked_item_t * it;
2756     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
2757         hci_connection_t * connection = (hci_connection_t *) it;
2758         if (connection->num_packets_completed){
2759             little_endian_store_16(packet, size, connection->con_handle);
2760             size += 2;
2761             little_endian_store_16(packet, size, connection->num_packets_completed);
2762             size += 2;
2763             //
2764             num_handles++;
2765             connection->num_packets_completed = 0;
2766         }
2767     }
2768 
2769     packet[2] = size - 3;
2770     packet[3] = num_handles;
2771 
2772     hci_stack->host_completed_packets = 0;
2773 
2774     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
2775     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
2776 
2777     // release packet buffer for synchronous transport implementations
2778     if (hci_transport_synchronous()){
2779         hci_stack->hci_packet_buffer_reserved = 0;
2780     }
2781 }
2782 #endif
2783 
2784 static void hci_run(void){
2785 
2786     // log_info("hci_run: entered");
2787     btstack_linked_item_t * it;
2788 
2789     // send continuation fragments first, as they block the prepared packet buffer
2790     if (hci_stack->acl_fragmentation_total_size > 0) {
2791         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
2792         hci_connection_t *connection = hci_connection_for_handle(con_handle);
2793         if (connection) {
2794             if (hci_can_send_prepared_acl_packet_now(con_handle)){
2795                 hci_send_acl_packet_fragments(connection);
2796                 return;
2797             }
2798         } else {
2799             // connection gone -> discard further fragments
2800             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
2801             hci_stack->acl_fragmentation_total_size = 0;
2802             hci_stack->acl_fragmentation_pos = 0;
2803         }
2804     }
2805 
2806 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
2807     // send host num completed packets next as they don't require num_cmd_packets > 0
2808     if (!hci_can_send_comand_packet_transport()) return;
2809     if (hci_stack->host_completed_packets){
2810         hci_host_num_completed_packets();
2811         return;
2812     }
2813 #endif
2814 
2815     if (!hci_can_send_command_packet_now()) return;
2816 
2817     // global/non-connection oriented commands
2818 
2819 #ifdef ENABLE_CLASSIC
2820     // decline incoming connections
2821     if (hci_stack->decline_reason){
2822         uint8_t reason = hci_stack->decline_reason;
2823         hci_stack->decline_reason = 0;
2824         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
2825         return;
2826     }
2827     // send scan enable
2828     if (hci_stack->state == HCI_STATE_WORKING && hci_stack->new_scan_enable_value != 0xff && hci_classic_supported()){
2829         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
2830         hci_stack->new_scan_enable_value = 0xff;
2831         return;
2832     }
2833     // start/stop inquiry
2834     if (hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN && hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX){
2835         uint8_t duration = hci_stack->inquiry_state;
2836         hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
2837         hci_send_cmd(&hci_inquiry, HCI_INQUIRY_LAP, duration, 0);
2838         return;
2839     }
2840     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
2841         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
2842         hci_send_cmd(&hci_inquiry_cancel);
2843         return;
2844     }
2845     // remote name request
2846     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
2847         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
2848         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
2849             hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
2850         return;
2851     }
2852     // pairing
2853     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
2854         uint8_t state = hci_stack->gap_pairing_state;
2855         hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
2856         switch (state){
2857             case GAP_PAIRING_STATE_SEND_PIN:
2858                 hci_send_cmd(&hci_pin_code_request_reply, hci_stack->gap_pairing_addr, strlen(hci_stack->gap_pairing_pin), hci_stack->gap_pairing_pin);
2859                 break;
2860             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
2861                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
2862                 break;
2863             case GAP_PAIRING_STATE_SEND_PASSKEY:
2864                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_passkey);
2865                 break;
2866             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
2867                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
2868                 break;
2869             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
2870                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
2871                 break;
2872             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
2873                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
2874                 break;
2875             default:
2876                 break;
2877         }
2878         return;
2879     }
2880 #endif
2881 
2882 #ifdef ENABLE_BLE
2883     // advertisements, active scanning, and creating connections requires randaom address to be set if using private address
2884     if ((hci_stack->state == HCI_STATE_WORKING)
2885     && (hci_stack->le_own_addr_type == BD_ADDR_TYPE_LE_PUBLIC || hci_stack->le_random_address_set)){
2886 
2887 #ifdef ENABLE_LE_CENTRAL
2888         // handle le scan
2889         switch(hci_stack->le_scanning_state){
2890             case LE_START_SCAN:
2891                 hci_stack->le_scanning_state = LE_SCANNING;
2892                 hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
2893                 return;
2894 
2895             case LE_STOP_SCAN:
2896                 hci_stack->le_scanning_state = LE_SCAN_IDLE;
2897                 hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
2898                 return;
2899             default:
2900                 break;
2901         }
2902         if (hci_stack->le_scan_type != 0xff){
2903             // defaults: active scanning, accept all advertisement packets
2904             int scan_type = hci_stack->le_scan_type;
2905             hci_stack->le_scan_type = 0xff;
2906             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);
2907             return;
2908         }
2909 #endif
2910 #ifdef ENABLE_LE_PERIPHERAL
2911         // le advertisement control
2912         if (hci_stack->le_advertisements_todo){
2913             log_info("hci_run: gap_le: adv todo: %x", hci_stack->le_advertisements_todo );
2914         }
2915         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_DISABLE){
2916             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_DISABLE;
2917             hci_send_cmd(&hci_le_set_advertise_enable, 0);
2918             return;
2919         }
2920         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
2921             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
2922             hci_send_cmd(&hci_le_set_advertising_parameters,
2923                  hci_stack->le_advertisements_interval_min,
2924                  hci_stack->le_advertisements_interval_max,
2925                  hci_stack->le_advertisements_type,
2926                  hci_stack->le_own_addr_type,
2927                  hci_stack->le_advertisements_direct_address_type,
2928                  hci_stack->le_advertisements_direct_address,
2929                  hci_stack->le_advertisements_channel_map,
2930                  hci_stack->le_advertisements_filter_policy);
2931             return;
2932         }
2933         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
2934             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
2935             hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, hci_stack->le_advertisements_data);
2936             return;
2937         }
2938         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
2939             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
2940             hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len,
2941                 hci_stack->le_scan_response_data);
2942             return;
2943         }
2944         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_ENABLE){
2945             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_ENABLE;
2946             hci_send_cmd(&hci_le_set_advertise_enable, 1);
2947             return;
2948         }
2949 #endif
2950 
2951 #ifdef ENABLE_LE_CENTRAL
2952         //
2953         // LE Whitelist Management
2954         //
2955 
2956         // check if whitelist needs modification
2957         btstack_linked_list_iterator_t lit;
2958         int modification_pending = 0;
2959         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
2960         while (btstack_linked_list_iterator_has_next(&lit)){
2961             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
2962             if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
2963                 modification_pending = 1;
2964                 break;
2965             }
2966         }
2967 
2968         if (modification_pending){
2969             // stop connnecting if modification pending
2970             if (hci_stack->le_connecting_state != LE_CONNECTING_IDLE){
2971                 hci_send_cmd(&hci_le_create_connection_cancel);
2972                 return;
2973             }
2974 
2975             // add/remove entries
2976             btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
2977             while (btstack_linked_list_iterator_has_next(&lit)){
2978                 whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
2979                 if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
2980                     entry->state = LE_WHITELIST_ON_CONTROLLER;
2981                     hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
2982                     return;
2983 
2984                 }
2985                 if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
2986                     bd_addr_t address;
2987                     bd_addr_type_t address_type = entry->address_type;
2988                     memcpy(address, entry->address, 6);
2989                     btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
2990                     btstack_memory_whitelist_entry_free(entry);
2991                     hci_send_cmd(&hci_le_remove_device_from_white_list, address_type, address);
2992                     return;
2993                 }
2994             }
2995         }
2996 
2997         // start connecting
2998         if ( hci_stack->le_connecting_state == LE_CONNECTING_IDLE &&
2999             !btstack_linked_list_empty(&hci_stack->le_whitelist)){
3000             bd_addr_t null_addr;
3001             memset(null_addr, 0, 6);
3002             hci_send_cmd(&hci_le_create_connection,
3003                  0x0060,    // scan interval: 60 ms
3004                  0x0030,    // scan interval: 30 ms
3005                  1,         // use whitelist
3006                  0,         // peer address type
3007                  null_addr, // peer bd addr
3008                  hci_stack->le_own_addr_type, // our addr type:
3009                  hci_stack->le_connection_interval_min,    // conn interval min
3010                  hci_stack->le_connection_interval_max,    // conn interval max
3011                  hci_stack->le_connection_latency,         // conn latency
3012                  hci_stack->le_supervision_timeout,        // conn latency
3013                  hci_stack->le_minimum_ce_length,          // min ce length
3014                  hci_stack->le_maximum_ce_length           // max ce length
3015                 );
3016             return;
3017         }
3018 #endif
3019     }
3020 #endif
3021 
3022     // send pending HCI commands
3023     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
3024         hci_connection_t * connection = (hci_connection_t *) it;
3025 
3026         switch(connection->state){
3027             case SEND_CREATE_CONNECTION:
3028                 switch(connection->address_type){
3029 #ifdef ENABLE_CLASSIC
3030                     case BD_ADDR_TYPE_CLASSIC:
3031                         log_info("sending hci_create_connection");
3032                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, 1);
3033                         break;
3034 #endif
3035                     default:
3036 #ifdef ENABLE_BLE
3037 #ifdef ENABLE_LE_CENTRAL
3038                         log_info("sending hci_le_create_connection");
3039                         hci_send_cmd(&hci_le_create_connection,
3040                              0x0060,    // scan interval: 60 ms
3041                              0x0030,    // scan interval: 30 ms
3042                              0,         // don't use whitelist
3043                              connection->address_type, // peer address type
3044                              connection->address,      // peer bd addr
3045                              hci_stack->le_own_addr_type, // our addr type:
3046                              hci_stack->le_connection_interval_min,    // conn interval min
3047                              hci_stack->le_connection_interval_max,    // conn interval max
3048                              hci_stack->le_connection_latency,         // conn latency
3049                              hci_stack->le_supervision_timeout,        // conn latency
3050                              hci_stack->le_minimum_ce_length,          // min ce length
3051                              hci_stack->le_maximum_ce_length          // max ce length
3052                              );
3053                         connection->state = SENT_CREATE_CONNECTION;
3054 #endif
3055 #endif
3056                         break;
3057                 }
3058                 return;
3059 
3060 #ifdef ENABLE_CLASSIC
3061             case RECEIVED_CONNECTION_REQUEST:
3062                 log_info("sending hci_accept_connection_request, remote eSCO %u", connection->remote_supported_feature_eSCO);
3063                 connection->state = ACCEPTED_CONNECTION_REQUEST;
3064                 connection->role  = HCI_ROLE_SLAVE;
3065                 if (connection->address_type == BD_ADDR_TYPE_CLASSIC){
3066                     hci_send_cmd(&hci_accept_connection_request, connection->address, 1);
3067                 }
3068                 return;
3069 #endif
3070 
3071 #ifdef ENABLE_BLE
3072 #ifdef ENABLE_LE_CENTRAL
3073             case SEND_CANCEL_CONNECTION:
3074                 connection->state = SENT_CANCEL_CONNECTION;
3075                 hci_send_cmd(&hci_le_create_connection_cancel);
3076                 return;
3077 #endif
3078 #endif
3079             case SEND_DISCONNECT:
3080                 connection->state = SENT_DISCONNECT;
3081                 hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13); // remote closed connection
3082                 return;
3083 
3084             default:
3085                 break;
3086         }
3087 
3088 #ifdef ENABLE_CLASSIC
3089         if (connection->authentication_flags & HANDLE_LINK_KEY_REQUEST){
3090             log_info("responding to link key request");
3091             connectionClearAuthenticationFlags(connection, HANDLE_LINK_KEY_REQUEST);
3092             link_key_t link_key;
3093             link_key_type_t link_key_type;
3094             if ( hci_stack->link_key_db
3095               && hci_stack->link_key_db->get_link_key(connection->address, link_key, &link_key_type)
3096               && gap_security_level_for_link_key_type(link_key_type) >= connection->requested_security_level){
3097                connection->link_key_type = link_key_type;
3098                hci_send_cmd(&hci_link_key_request_reply, connection->address, &link_key);
3099             } else {
3100                hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
3101             }
3102             return;
3103         }
3104 
3105         if (connection->authentication_flags & DENY_PIN_CODE_REQUEST){
3106             log_info("denying to pin request");
3107             connectionClearAuthenticationFlags(connection, DENY_PIN_CODE_REQUEST);
3108             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
3109             return;
3110         }
3111 
3112         if (connection->authentication_flags & SEND_IO_CAPABILITIES_REPLY){
3113             connectionClearAuthenticationFlags(connection, SEND_IO_CAPABILITIES_REPLY);
3114             log_info("IO Capability Request received, stack bondable %u, io cap %u", hci_stack->bondable, hci_stack->ssp_io_capability);
3115             if (hci_stack->bondable && (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN)){
3116                 // tweak authentication requirements
3117                 uint8_t authreq = hci_stack->ssp_authentication_requirement;
3118                 if (connection->bonding_flags & BONDING_DEDICATED){
3119                     authreq = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
3120                 }
3121                 if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
3122                     authreq |= 1;
3123                 }
3124                 hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, NULL, authreq);
3125             } else {
3126                 hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
3127             }
3128             return;
3129         }
3130 
3131         if (connection->authentication_flags & SEND_USER_CONFIRM_REPLY){
3132             connectionClearAuthenticationFlags(connection, SEND_USER_CONFIRM_REPLY);
3133             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
3134             return;
3135         }
3136 
3137         if (connection->authentication_flags & SEND_USER_PASSKEY_REPLY){
3138             connectionClearAuthenticationFlags(connection, SEND_USER_PASSKEY_REPLY);
3139             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
3140             return;
3141         }
3142 
3143         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES){
3144             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES;
3145             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
3146             return;
3147         }
3148 
3149         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
3150             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
3151             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
3152             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // authentication done
3153             return;
3154         }
3155 
3156         if (connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST){
3157             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
3158             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
3159             return;
3160         }
3161 
3162         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
3163             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
3164             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
3165             return;
3166         }
3167 #endif
3168 
3169         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
3170             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
3171             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x0005);  // authentication failure
3172             return;
3173         }
3174 
3175 #ifdef ENABLE_BLE
3176         if (connection->le_con_parameter_update_state == CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS){
3177             connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
3178 
3179             uint16_t connection_interval_min = connection->le_conn_interval_min;
3180             connection->le_conn_interval_min = 0;
3181             hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection_interval_min,
3182                 connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
3183                 0x0000, 0xffff);
3184         }
3185 #endif
3186     }
3187 
3188     hci_connection_t * connection;
3189     switch (hci_stack->state){
3190         case HCI_STATE_INITIALIZING:
3191             hci_initializing_run();
3192             break;
3193 
3194         case HCI_STATE_HALTING:
3195 
3196             log_info("HCI_STATE_HALTING");
3197 
3198             // free whitelist entries
3199 #ifdef ENABLE_BLE
3200 #ifdef ENABLE_LE_CENTRAL
3201             {
3202                 btstack_linked_list_iterator_t lit;
3203                 btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3204                 while (btstack_linked_list_iterator_has_next(&lit)){
3205                     whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3206                     btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
3207                     btstack_memory_whitelist_entry_free(entry);
3208                 }
3209             }
3210 #endif
3211 #endif
3212             // close all open connections
3213             connection =  (hci_connection_t *) hci_stack->connections;
3214             if (connection){
3215                 hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
3216                 if (!hci_can_send_command_packet_now()) return;
3217 
3218                 log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
3219 
3220                 // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
3221                 hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
3222 
3223                 // ... which would be ignored anyway as we shutdown (free) the connection now
3224                 hci_shutdown_connection(connection);
3225 
3226                 // finally, send the disconnect command
3227                 hci_send_cmd(&hci_disconnect, con_handle, 0x13);  // remote closed connection
3228                 return;
3229             }
3230             log_info("HCI_STATE_HALTING, calling off");
3231 
3232             // switch mode
3233             hci_power_control_off();
3234 
3235             log_info("HCI_STATE_HALTING, emitting state");
3236             hci_emit_state();
3237             log_info("HCI_STATE_HALTING, done");
3238             break;
3239 
3240         case HCI_STATE_FALLING_ASLEEP:
3241             switch(hci_stack->substate) {
3242                 case HCI_FALLING_ASLEEP_DISCONNECT:
3243                     log_info("HCI_STATE_FALLING_ASLEEP");
3244                     // close all open connections
3245                     connection =  (hci_connection_t *) hci_stack->connections;
3246 
3247 #ifdef HAVE_PLATFORM_IPHONE_OS
3248                     // don't close connections, if H4 supports power management
3249                     if (btstack_control_iphone_power_management_enabled()){
3250                         connection = NULL;
3251                     }
3252 #endif
3253                     if (connection){
3254 
3255                         // send disconnect
3256                         if (!hci_can_send_command_packet_now()) return;
3257 
3258                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
3259                         hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // remote closed connection
3260 
3261                         // send disconnected event right away - causes higher layer connections to get closed, too.
3262                         hci_shutdown_connection(connection);
3263                         return;
3264                     }
3265 
3266                     if (hci_classic_supported()){
3267                         // disable page and inquiry scan
3268                         if (!hci_can_send_command_packet_now()) return;
3269 
3270                         log_info("HCI_STATE_HALTING, disabling inq scans");
3271                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
3272 
3273                         // continue in next sub state
3274                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
3275                         break;
3276                     }
3277                     // no break - fall through for ble-only chips
3278 
3279                 case HCI_FALLING_ASLEEP_COMPLETE:
3280                     log_info("HCI_STATE_HALTING, calling sleep");
3281 #ifdef HAVE_PLATFORM_IPHONE_OS
3282                     // don't actually go to sleep, if H4 supports power management
3283                     if (btstack_control_iphone_power_management_enabled()){
3284                         // SLEEP MODE reached
3285                         hci_stack->state = HCI_STATE_SLEEPING;
3286                         hci_emit_state();
3287                         break;
3288                     }
3289 #endif
3290                     // switch mode
3291                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
3292                     hci_emit_state();
3293                     break;
3294 
3295                 default:
3296                     break;
3297             }
3298             break;
3299 
3300         default:
3301             break;
3302     }
3303 }
3304 
3305 int hci_send_cmd_packet(uint8_t *packet, int size){
3306     // house-keeping
3307 
3308     if (IS_COMMAND(packet, hci_write_loopback_mode)){
3309         hci_stack->loopback_mode = packet[3];
3310     }
3311 
3312 #ifdef ENABLE_CLASSIC
3313     bd_addr_t addr;
3314     hci_connection_t * conn;
3315 
3316     // create_connection?
3317     if (IS_COMMAND(packet, hci_create_connection)){
3318         reverse_bd_addr(&packet[3], addr);
3319         log_info("Create_connection to %s", bd_addr_to_str(addr));
3320 
3321         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
3322         if (!conn){
3323             conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
3324             if (!conn){
3325                 // notify client that alloc failed
3326                 hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
3327                 return 0; // don't sent packet to controller
3328             }
3329             conn->state = SEND_CREATE_CONNECTION;
3330         }
3331         log_info("conn state %u", conn->state);
3332         switch (conn->state){
3333             // if connection active exists
3334             case OPEN:
3335                 // and OPEN, emit connection complete command, don't send to controller
3336                 hci_emit_connection_complete(addr, conn->con_handle, 0);
3337                 return 0;
3338             case SEND_CREATE_CONNECTION:
3339                 // connection created by hci, e.g. dedicated bonding
3340                 break;
3341             default:
3342                 // otherwise, just ignore as it is already in the open process
3343                 return 0;
3344         }
3345         conn->state = SENT_CREATE_CONNECTION;
3346     }
3347 
3348     if (IS_COMMAND(packet, hci_link_key_request_reply)){
3349         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
3350     }
3351     if (IS_COMMAND(packet, hci_link_key_request_negative_reply)){
3352         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
3353     }
3354 
3355     if (IS_COMMAND(packet, hci_delete_stored_link_key)){
3356         if (hci_stack->link_key_db){
3357             reverse_bd_addr(&packet[3], addr);
3358             hci_stack->link_key_db->delete_link_key(addr);
3359         }
3360     }
3361 
3362     if (IS_COMMAND(packet, hci_pin_code_request_negative_reply)
3363     ||  IS_COMMAND(packet, hci_pin_code_request_reply)){
3364         reverse_bd_addr(&packet[3], addr);
3365         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
3366         if (conn){
3367             connectionClearAuthenticationFlags(conn, LEGACY_PAIRING_ACTIVE);
3368         }
3369     }
3370 
3371     if (IS_COMMAND(packet, hci_user_confirmation_request_negative_reply)
3372     ||  IS_COMMAND(packet, hci_user_confirmation_request_reply)
3373     ||  IS_COMMAND(packet, hci_user_passkey_request_negative_reply)
3374     ||  IS_COMMAND(packet, hci_user_passkey_request_reply)) {
3375         reverse_bd_addr(&packet[3], addr);
3376         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
3377         if (conn){
3378             connectionClearAuthenticationFlags(conn, SSP_PAIRING_ACTIVE);
3379         }
3380     }
3381 
3382 #ifdef ENABLE_SCO_OVER_HCI
3383     // setup_synchronous_connection? Voice setting at offset 22
3384     if (IS_COMMAND(packet, hci_setup_synchronous_connection)){
3385         // TODO: compare to current setting if sco connection already active
3386         hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
3387     }
3388     // accept_synchronus_connection? Voice setting at offset 18
3389     if (IS_COMMAND(packet, hci_accept_synchronous_connection)){
3390         // TODO: compare to current setting if sco connection already active
3391         hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
3392     }
3393 #endif
3394 #endif
3395 
3396 #ifdef ENABLE_BLE
3397 #ifdef ENABLE_LE_PERIPHERAL
3398     if (IS_COMMAND(packet, hci_le_set_random_address)){
3399         hci_stack->le_random_address_set = 1;
3400         reverse_bd_addr(&packet[3], hci_stack->le_random_address);
3401     }
3402     if (IS_COMMAND(packet, hci_le_set_advertise_enable)){
3403         hci_stack->le_advertisements_active = packet[3];
3404     }
3405 #endif
3406 #ifdef ENABLE_LE_CENTRAL
3407     if (IS_COMMAND(packet, hci_le_create_connection)){
3408         // white list used?
3409         uint8_t initiator_filter_policy = packet[7];
3410         switch (initiator_filter_policy){
3411             case 0:
3412                 // whitelist not used
3413                 hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
3414                 break;
3415             case 1:
3416                 hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
3417                 break;
3418             default:
3419                 log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
3420                 break;
3421         }
3422     }
3423     if (IS_COMMAND(packet, hci_le_create_connection_cancel)){
3424         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
3425     }
3426 #endif
3427 #endif
3428 
3429     hci_stack->num_cmd_packets--;
3430 
3431     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
3432     int err = hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
3433 
3434     // release packet buffer for synchronous transport implementations
3435     if (hci_transport_synchronous() && (packet == hci_stack->hci_packet_buffer)){
3436         hci_stack->hci_packet_buffer_reserved = 0;
3437     }
3438 
3439     return err;
3440 }
3441 
3442 // disconnect because of security block
3443 void hci_disconnect_security_block(hci_con_handle_t con_handle){
3444     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3445     if (!connection) return;
3446     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
3447 }
3448 
3449 
3450 // Configure Secure Simple Pairing
3451 
3452 #ifdef ENABLE_CLASSIC
3453 
3454 // enable will enable SSP during init
3455 void gap_ssp_set_enable(int enable){
3456     hci_stack->ssp_enable = enable;
3457 }
3458 
3459 static int hci_local_ssp_activated(void){
3460     return gap_ssp_supported() && hci_stack->ssp_enable;
3461 }
3462 
3463 // if set, BTstack will respond to io capability request using authentication requirement
3464 void gap_ssp_set_io_capability(int io_capability){
3465     hci_stack->ssp_io_capability = io_capability;
3466 }
3467 void gap_ssp_set_authentication_requirement(int authentication_requirement){
3468     hci_stack->ssp_authentication_requirement = authentication_requirement;
3469 }
3470 
3471 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
3472 void gap_ssp_set_auto_accept(int auto_accept){
3473     hci_stack->ssp_auto_accept = auto_accept;
3474 }
3475 #endif
3476 
3477 // va_list part of hci_send_cmd
3478 int hci_send_cmd_va_arg(const hci_cmd_t *cmd, va_list argptr){
3479     if (!hci_can_send_command_packet_now()){
3480         log_error("hci_send_cmd called but cannot send packet now");
3481         return 0;
3482     }
3483 
3484     // for HCI INITIALIZATION
3485     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
3486     hci_stack->last_cmd_opcode = cmd->opcode;
3487 
3488     hci_reserve_packet_buffer();
3489     uint8_t * packet = hci_stack->hci_packet_buffer;
3490     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
3491     return hci_send_cmd_packet(packet, size);
3492 }
3493 
3494 /**
3495  * pre: numcmds >= 0 - it's allowed to send a command to the controller
3496  */
3497 int hci_send_cmd(const hci_cmd_t *cmd, ...){
3498     va_list argptr;
3499     va_start(argptr, cmd);
3500     int res = hci_send_cmd_va_arg(cmd, argptr);
3501     va_end(argptr);
3502     return res;
3503 }
3504 
3505 // Create various non-HCI events.
3506 // TODO: generalize, use table similar to hci_create_command
3507 
3508 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
3509     // dump packet
3510     if (dump) {
3511         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
3512     }
3513 
3514     // dispatch to all event handlers
3515     btstack_linked_list_iterator_t it;
3516     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
3517     while (btstack_linked_list_iterator_has_next(&it)){
3518         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
3519         entry->callback(HCI_EVENT_PACKET, 0, event, size);
3520     }
3521 }
3522 
3523 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
3524     if (!hci_stack->acl_packet_handler) return;
3525     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
3526 }
3527 
3528 #ifdef ENABLE_CLASSIC
3529 static void hci_notify_if_sco_can_send_now(void){
3530     // notify SCO sender if waiting
3531     if (!hci_stack->sco_waiting_for_can_send_now) return;
3532     if (hci_can_send_sco_packet_now()){
3533         hci_stack->sco_waiting_for_can_send_now = 0;
3534         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
3535         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
3536         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
3537     }
3538 }
3539 
3540 // parsing end emitting has been merged to reduce code size
3541 static void gap_inquiry_explode(uint8_t * packet){
3542     uint8_t event[15+GAP_INQUIRY_MAX_NAME_LEN];
3543 
3544     uint8_t * eir_data;
3545     ad_context_t context;
3546     const uint8_t * name;
3547     uint8_t         name_len;
3548 
3549     int event_type = hci_event_packet_get_type(packet);
3550     int num_reserved_fields = event_type == HCI_EVENT_INQUIRY_RESULT ? 2 : 1;    // 2 for old event, 1 otherwise
3551     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
3552 
3553     // event[1] is set at the end
3554     int i;
3555     for (i=0; i<num_responses;i++){
3556         memset(event, 0, sizeof(event));
3557         event[0] = GAP_EVENT_INQUIRY_RESULT;
3558         uint8_t event_size = 18;    // if name is not set by EIR
3559 
3560         memcpy(&event[2],  &packet[3 +                                             i*6], 6); // bd_addr
3561         event[8] =          packet[3 + num_responses*(6)                         + i*1];     // page_scan_repetition_mode
3562         memcpy(&event[9],  &packet[3 + num_responses*(6+1+num_reserved_fields)   + i*3], 3); // class of device
3563         memcpy(&event[12], &packet[3 + num_responses*(6+1+num_reserved_fields+3) + i*2], 2); // clock offset
3564 
3565         switch (event_type){
3566             case HCI_EVENT_INQUIRY_RESULT:
3567                 // 14,15,16,17 = 0, size 18
3568                 break;
3569             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
3570                 event[14] = 1;
3571                 event[15] = packet [3 + num_responses*(6+1+num_reserved_fields+3+2) + i*1]; // rssi
3572                 // 16,17 = 0, size 18
3573                 break;
3574             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
3575                 event[14] = 1;
3576                 event[15] = packet [3 + num_responses*(6+1+num_reserved_fields+3+2) + i*1]; // rssi
3577                 // for EIR packets, there is only one reponse in it
3578                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
3579                 name = NULL;
3580                 // EIR data is 240 bytes in EIR event
3581                 for (ad_iterator_init(&context, 240, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
3582                     uint8_t data_type    = ad_iterator_get_data_type(&context);
3583                     uint8_t data_size    = ad_iterator_get_data_len(&context);
3584                     const uint8_t * data = ad_iterator_get_data(&context);
3585                     // Prefer Complete Local Name over Shortend Local Name
3586                     switch (data_type){
3587                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
3588                             if (name) continue;
3589                             /* explicit fall-through */
3590                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
3591                             name = data;
3592                             name_len = data_size;
3593                             break;
3594                         default:
3595                             break;
3596                     }
3597                 }
3598                 if (name){
3599                     event[16] = 1;
3600                     // truncate name if needed
3601                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
3602                     event[17] = len;
3603                     memcpy(&event[18], name, len);
3604                     event_size += len;
3605                 }
3606                 break;
3607         }
3608         event[1] = event_size - 2;
3609         hci_emit_event(event, event_size, 1);
3610     }
3611 }
3612 #endif
3613 
3614 void hci_emit_state(void){
3615     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
3616     uint8_t event[3];
3617     event[0] = BTSTACK_EVENT_STATE;
3618     event[1] = sizeof(event) - 2;
3619     event[2] = hci_stack->state;
3620     hci_emit_event(event, sizeof(event), 1);
3621 }
3622 
3623 #ifdef ENABLE_CLASSIC
3624 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
3625     uint8_t event[13];
3626     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
3627     event[1] = sizeof(event) - 2;
3628     event[2] = status;
3629     little_endian_store_16(event, 3, con_handle);
3630     reverse_bd_addr(address, &event[5]);
3631     event[11] = 1; // ACL connection
3632     event[12] = 0; // encryption disabled
3633     hci_emit_event(event, sizeof(event), 1);
3634 }
3635 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
3636     if (disable_l2cap_timeouts) return;
3637     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
3638     uint8_t event[4];
3639     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
3640     event[1] = sizeof(event) - 2;
3641     little_endian_store_16(event, 2, conn->con_handle);
3642     hci_emit_event(event, sizeof(event), 1);
3643 }
3644 #endif
3645 
3646 #ifdef ENABLE_BLE
3647 #ifdef ENABLE_LE_CENTRAL
3648 static void hci_emit_le_connection_complete(uint8_t address_type, bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
3649     uint8_t event[21];
3650     event[0] = HCI_EVENT_LE_META;
3651     event[1] = sizeof(event) - 2;
3652     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
3653     event[3] = status;
3654     little_endian_store_16(event, 4, con_handle);
3655     event[6] = 0; // TODO: role
3656     event[7] = address_type;
3657     reverse_bd_addr(address, &event[8]);
3658     little_endian_store_16(event, 14, 0); // interval
3659     little_endian_store_16(event, 16, 0); // latency
3660     little_endian_store_16(event, 18, 0); // supervision timeout
3661     event[20] = 0; // master clock accuracy
3662     hci_emit_event(event, sizeof(event), 1);
3663 }
3664 #endif
3665 #endif
3666 
3667 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
3668     uint8_t event[6];
3669     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
3670     event[1] = sizeof(event) - 2;
3671     event[2] = 0; // status = OK
3672     little_endian_store_16(event, 3, con_handle);
3673     event[5] = reason;
3674     hci_emit_event(event, sizeof(event), 1);
3675 }
3676 
3677 static void hci_emit_nr_connections_changed(void){
3678     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
3679     uint8_t event[3];
3680     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
3681     event[1] = sizeof(event) - 2;
3682     event[2] = nr_hci_connections();
3683     hci_emit_event(event, sizeof(event), 1);
3684 }
3685 
3686 static void hci_emit_hci_open_failed(void){
3687     log_info("BTSTACK_EVENT_POWERON_FAILED");
3688     uint8_t event[2];
3689     event[0] = BTSTACK_EVENT_POWERON_FAILED;
3690     event[1] = sizeof(event) - 2;
3691     hci_emit_event(event, sizeof(event), 1);
3692 }
3693 
3694 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
3695     log_info("hci_emit_dedicated_bonding_result %u ", status);
3696     uint8_t event[9];
3697     int pos = 0;
3698     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
3699     event[pos++] = sizeof(event) - 2;
3700     event[pos++] = status;
3701     reverse_bd_addr(address, &event[pos]);
3702     hci_emit_event(event, sizeof(event), 1);
3703 }
3704 
3705 
3706 #ifdef ENABLE_CLASSIC
3707 
3708 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
3709     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
3710     uint8_t event[5];
3711     int pos = 0;
3712     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
3713     event[pos++] = sizeof(event) - 2;
3714     little_endian_store_16(event, 2, con_handle);
3715     pos += 2;
3716     event[pos++] = level;
3717     hci_emit_event(event, sizeof(event), 1);
3718 }
3719 
3720 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
3721     if (!connection) return LEVEL_0;
3722     if ((connection->authentication_flags & CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
3723     return gap_security_level_for_link_key_type(connection->link_key_type);
3724 }
3725 
3726 static void hci_emit_discoverable_enabled(uint8_t enabled){
3727     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
3728     uint8_t event[3];
3729     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
3730     event[1] = sizeof(event) - 2;
3731     event[2] = enabled;
3732     hci_emit_event(event, sizeof(event), 1);
3733 }
3734 
3735 #ifdef ENABLE_CLASSIC
3736 // query if remote side supports eSCO
3737 int hci_remote_esco_supported(hci_con_handle_t con_handle){
3738     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3739     if (!connection) return 0;
3740     return connection->remote_supported_feature_eSCO;
3741 }
3742 
3743 // query if remote side supports SSP
3744 int hci_remote_ssp_supported(hci_con_handle_t con_handle){
3745     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3746     if (!connection) return 0;
3747     return (connection->bonding_flags & BONDING_REMOTE_SUPPORTS_SSP) ? 1 : 0;
3748 }
3749 
3750 int gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
3751     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
3752 }
3753 #endif
3754 
3755 // GAP API
3756 /**
3757  * @bbrief enable/disable bonding. default is enabled
3758  * @praram enabled
3759  */
3760 void gap_set_bondable_mode(int enable){
3761     hci_stack->bondable = enable ? 1 : 0;
3762 }
3763 /**
3764  * @brief Get bondable mode.
3765  * @return 1 if bondable
3766  */
3767 int gap_get_bondable_mode(void){
3768     return hci_stack->bondable;
3769 }
3770 
3771 /**
3772  * @brief map link keys to security levels
3773  */
3774 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
3775     switch (link_key_type){
3776         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
3777             return LEVEL_4;
3778         case COMBINATION_KEY:
3779         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
3780             return LEVEL_3;
3781         default:
3782             return LEVEL_2;
3783     }
3784 }
3785 
3786 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
3787     log_info("gap_mitm_protection_required_for_security_level %u", level);
3788     return level > LEVEL_2;
3789 }
3790 
3791 /**
3792  * @brief get current security level
3793  */
3794 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
3795     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3796     if (!connection) return LEVEL_0;
3797     return gap_security_level_for_connection(connection);
3798 }
3799 
3800 /**
3801  * @brief request connection to device to
3802  * @result GAP_AUTHENTICATION_RESULT
3803  */
3804 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
3805     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3806     if (!connection){
3807         hci_emit_security_level(con_handle, LEVEL_0);
3808         return;
3809     }
3810     gap_security_level_t current_level = gap_security_level(con_handle);
3811     log_info("gap_request_security_level %u, current level %u", requested_level, current_level);
3812     if (current_level >= requested_level){
3813         hci_emit_security_level(con_handle, current_level);
3814         return;
3815     }
3816 
3817     connection->requested_security_level = requested_level;
3818 
3819 #if 0
3820     // sending encryption request without a link key results in an error.
3821     // TODO: figure out how to use it properly
3822 
3823     // would enabling ecnryption suffice (>= LEVEL_2)?
3824     if (hci_stack->link_key_db){
3825         link_key_type_t link_key_type;
3826         link_key_t      link_key;
3827         if (hci_stack->link_key_db->get_link_key( &connection->address, &link_key, &link_key_type)){
3828             if (gap_security_level_for_link_key_type(link_key_type) >= requested_level){
3829                 connection->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
3830                 return;
3831             }
3832         }
3833     }
3834 #endif
3835 
3836     // try to authenticate connection
3837     connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
3838     hci_run();
3839 }
3840 
3841 /**
3842  * @brief start dedicated bonding with device. disconnect after bonding
3843  * @param device
3844  * @param request MITM protection
3845  * @result GAP_DEDICATED_BONDING_COMPLETE
3846  */
3847 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
3848 
3849     // create connection state machine
3850     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_CLASSIC);
3851 
3852     if (!connection){
3853         return BTSTACK_MEMORY_ALLOC_FAILED;
3854     }
3855 
3856     // delete linkn key
3857     gap_drop_link_key_for_bd_addr(device);
3858 
3859     // configure LEVEL_2/3, dedicated bonding
3860     connection->state = SEND_CREATE_CONNECTION;
3861     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
3862     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
3863     connection->bonding_flags = BONDING_DEDICATED;
3864 
3865     // wait for GAP Security Result and send GAP Dedicated Bonding complete
3866 
3867     // handle: connnection failure (connection complete != ok)
3868     // handle: authentication failure
3869     // handle: disconnect on done
3870 
3871     hci_run();
3872 
3873     return 0;
3874 }
3875 #endif
3876 
3877 void gap_set_local_name(const char * local_name){
3878     hci_stack->local_name = local_name;
3879 }
3880 
3881 
3882 #ifdef ENABLE_BLE
3883 
3884 #ifdef ENABLE_LE_CENTRAL
3885 void gap_start_scan(void){
3886     if (hci_stack->le_scanning_state == LE_SCANNING) return;
3887     hci_stack->le_scanning_state = LE_START_SCAN;
3888     hci_run();
3889 }
3890 
3891 void gap_stop_scan(void){
3892     if ( hci_stack->le_scanning_state == LE_SCAN_IDLE) return;
3893     hci_stack->le_scanning_state = LE_STOP_SCAN;
3894     hci_run();
3895 }
3896 
3897 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
3898     hci_stack->le_scan_type     = scan_type;
3899     hci_stack->le_scan_interval = scan_interval;
3900     hci_stack->le_scan_window   = scan_window;
3901     hci_run();
3902 }
3903 
3904 uint8_t gap_connect(bd_addr_t addr, bd_addr_type_t addr_type){
3905     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
3906     if (!conn){
3907         log_info("gap_connect: no connection exists yet, creating context");
3908         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
3909         if (!conn){
3910             // notify client that alloc failed
3911             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
3912             log_info("gap_connect: failed to alloc hci_connection_t");
3913             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
3914         }
3915         conn->state = SEND_CREATE_CONNECTION;
3916         log_info("gap_connect: send create connection next");
3917         hci_run();
3918         return 0;
3919     }
3920 
3921     if (!hci_is_le_connection(conn) ||
3922         conn->state == SEND_CREATE_CONNECTION ||
3923         conn->state == SENT_CREATE_CONNECTION) {
3924         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
3925         log_error("gap_connect: classic connection or connect is already being created");
3926         return GATT_CLIENT_IN_WRONG_STATE;
3927     }
3928 
3929     log_info("gap_connect: context exists with state %u", conn->state);
3930     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, 0);
3931     hci_run();
3932     return 0;
3933 }
3934 
3935 // @assumption: only a single outgoing LE Connection exists
3936 static hci_connection_t * gap_get_outgoing_connection(void){
3937     btstack_linked_item_t *it;
3938     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
3939         hci_connection_t * conn = (hci_connection_t *) it;
3940         if (!hci_is_le_connection(conn)) continue;
3941         switch (conn->state){
3942             case SEND_CREATE_CONNECTION:
3943             case SENT_CREATE_CONNECTION:
3944                 return conn;
3945             default:
3946                 break;
3947         };
3948     }
3949     return NULL;
3950 }
3951 
3952 uint8_t gap_connect_cancel(void){
3953     hci_connection_t * conn = gap_get_outgoing_connection();
3954     if (!conn) return 0;
3955     switch (conn->state){
3956         case SEND_CREATE_CONNECTION:
3957             // skip sending create connection and emit event instead
3958             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
3959             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
3960             btstack_memory_hci_connection_free( conn );
3961             break;
3962         case SENT_CREATE_CONNECTION:
3963             // request to send cancel connection
3964             conn->state = SEND_CANCEL_CONNECTION;
3965             hci_run();
3966             break;
3967         default:
3968             break;
3969     }
3970     return 0;
3971 }
3972 #endif
3973 
3974 #ifdef ENABLE_LE_CENTRAL
3975 /**
3976  * @brief Set connection parameters for outgoing connections
3977  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
3978  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
3979  * @param conn_latency, default: 4
3980  * @param supervision_timeout (unit: 10ms), default: 720 ms
3981  * @param min_ce_length (unit: 0.625ms), default: 10 ms
3982  * @param max_ce_length (unit: 0.625ms), default: 30 ms
3983  */
3984 
3985 void gap_set_connection_parameters(uint16_t conn_interval_min, uint16_t conn_interval_max,
3986     uint16_t conn_latency, uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
3987     hci_stack->le_connection_interval_min = conn_interval_min;
3988     hci_stack->le_connection_interval_max = conn_interval_max;
3989     hci_stack->le_connection_latency = conn_latency;
3990     hci_stack->le_supervision_timeout = supervision_timeout;
3991     hci_stack->le_minimum_ce_length = min_ce_length;
3992     hci_stack->le_maximum_ce_length = max_ce_length;
3993 }
3994 #endif
3995 
3996 /**
3997  * @brief Updates the connection parameters for a given LE connection
3998  * @param handle
3999  * @param conn_interval_min (unit: 1.25ms)
4000  * @param conn_interval_max (unit: 1.25ms)
4001  * @param conn_latency
4002  * @param supervision_timeout (unit: 10ms)
4003  * @returns 0 if ok
4004  */
4005 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
4006     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
4007     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4008     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
4009     connection->le_conn_interval_min = conn_interval_min;
4010     connection->le_conn_interval_max = conn_interval_max;
4011     connection->le_conn_latency = conn_latency;
4012     connection->le_supervision_timeout = supervision_timeout;
4013     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
4014     hci_run();
4015     return 0;
4016 }
4017 
4018 /**
4019  * @brief Request an update of the connection parameter for a given LE connection
4020  * @param handle
4021  * @param conn_interval_min (unit: 1.25ms)
4022  * @param conn_interval_max (unit: 1.25ms)
4023  * @param conn_latency
4024  * @param supervision_timeout (unit: 10ms)
4025  * @returns 0 if ok
4026  */
4027 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
4028     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
4029     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4030     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
4031     connection->le_conn_interval_min = conn_interval_min;
4032     connection->le_conn_interval_max = conn_interval_max;
4033     connection->le_conn_latency = conn_latency;
4034     connection->le_supervision_timeout = supervision_timeout;
4035     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
4036     hci_run();
4037     return 0;
4038 }
4039 
4040 #ifdef ENABLE_LE_PERIPHERAL
4041 
4042 static void gap_advertisments_changed(void){
4043     // disable advertisements before updating adv, scan data, or adv params
4044     if (hci_stack->le_advertisements_active){
4045         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE | LE_ADVERTISEMENT_TASKS_ENABLE;
4046     }
4047     hci_run();
4048 }
4049 
4050 /**
4051  * @brief Set Advertisement Data
4052  * @param advertising_data_length
4053  * @param advertising_data (max 31 octets)
4054  * @note data is not copied, pointer has to stay valid
4055  */
4056 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
4057     hci_stack->le_advertisements_data_len = advertising_data_length;
4058     hci_stack->le_advertisements_data = advertising_data;
4059     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
4060     gap_advertisments_changed();
4061 }
4062 
4063 /**
4064  * @brief Set Scan Response Data
4065  * @param advertising_data_length
4066  * @param advertising_data (max 31 octets)
4067  * @note data is not copied, pointer has to stay valid
4068  */
4069 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
4070     hci_stack->le_scan_response_data_len = scan_response_data_length;
4071     hci_stack->le_scan_response_data = scan_response_data;
4072     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
4073     gap_advertisments_changed();
4074 }
4075 
4076 /**
4077  * @brief Set Advertisement Parameters
4078  * @param adv_int_min
4079  * @param adv_int_max
4080  * @param adv_type
4081  * @param direct_address_type
4082  * @param direct_address
4083  * @param channel_map
4084  * @param filter_policy
4085  *
4086  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
4087  */
4088  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
4089     uint8_t direct_address_typ, bd_addr_t direct_address,
4090     uint8_t channel_map, uint8_t filter_policy) {
4091 
4092     hci_stack->le_advertisements_interval_min = adv_int_min;
4093     hci_stack->le_advertisements_interval_max = adv_int_max;
4094     hci_stack->le_advertisements_type = adv_type;
4095     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
4096     hci_stack->le_advertisements_channel_map = channel_map;
4097     hci_stack->le_advertisements_filter_policy = filter_policy;
4098     memcpy(hci_stack->le_advertisements_direct_address, direct_address, 6);
4099 
4100     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
4101     gap_advertisments_changed();
4102  }
4103 
4104 /**
4105  * @brief Enable/Disable Advertisements
4106  * @param enabled
4107  */
4108 void gap_advertisements_enable(int enabled){
4109     hci_stack->le_advertisements_enabled = enabled;
4110     if (enabled && !hci_stack->le_advertisements_active){
4111         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
4112     }
4113     if (!enabled && hci_stack->le_advertisements_active){
4114         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE;
4115     }
4116     hci_run();
4117 }
4118 
4119 #endif
4120 
4121 void hci_le_set_own_address_type(uint8_t own_address_type){
4122     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
4123     if (own_address_type == hci_stack->le_own_addr_type) return;
4124     hci_stack->le_own_addr_type = own_address_type;
4125 
4126 #ifdef ENABLE_LE_PERIPHERAL
4127     // update advertisement parameters, too
4128     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
4129     gap_advertisments_changed();
4130 #endif
4131 #ifdef ENABLE_LE_CENTRAL
4132     // note: we don't update scan parameters or modify ongoing connection attempts
4133 #endif
4134 }
4135 
4136 #endif
4137 
4138 uint8_t gap_disconnect(hci_con_handle_t handle){
4139     hci_connection_t * conn = hci_connection_for_handle(handle);
4140     if (!conn){
4141         hci_emit_disconnection_complete(handle, 0);
4142         return 0;
4143     }
4144     conn->state = SEND_DISCONNECT;
4145     hci_run();
4146     return 0;
4147 }
4148 
4149 /**
4150  * @brief Get connection type
4151  * @param con_handle
4152  * @result connection_type
4153  */
4154 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
4155     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
4156     if (!conn) return GAP_CONNECTION_INVALID;
4157     switch (conn->address_type){
4158         case BD_ADDR_TYPE_LE_PUBLIC:
4159         case BD_ADDR_TYPE_LE_RANDOM:
4160             return GAP_CONNECTION_LE;
4161         case BD_ADDR_TYPE_SCO:
4162             return GAP_CONNECTION_SCO;
4163         case BD_ADDR_TYPE_CLASSIC:
4164             return GAP_CONNECTION_ACL;
4165         default:
4166             return GAP_CONNECTION_INVALID;
4167     }
4168 }
4169 
4170 #ifdef ENABLE_BLE
4171 
4172 #ifdef ENABLE_LE_CENTRAL
4173 /**
4174  * @brief Auto Connection Establishment - Start Connecting to device
4175  * @param address_typ
4176  * @param address
4177  * @returns 0 if ok
4178  */
4179 int gap_auto_connection_start(bd_addr_type_t address_type, bd_addr_t address){
4180     // check capacity
4181     int num_entries = btstack_linked_list_count(&hci_stack->le_whitelist);
4182     if (num_entries >= hci_stack->le_whitelist_capacity) return ERROR_CODE_MEMORY_CAPACITY_EXCEEDED;
4183     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
4184     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
4185     entry->address_type = address_type;
4186     memcpy(entry->address, address, 6);
4187     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
4188     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
4189     hci_run();
4190     return 0;
4191 }
4192 
4193 static void hci_remove_from_whitelist(bd_addr_type_t address_type, bd_addr_t address){
4194     btstack_linked_list_iterator_t it;
4195     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
4196     while (btstack_linked_list_iterator_has_next(&it)){
4197         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
4198         if (entry->address_type != address_type) continue;
4199         if (memcmp(entry->address, address, 6) != 0) continue;
4200         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
4201             // remove from controller if already present
4202             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
4203             continue;
4204         }
4205         // direclty remove entry from whitelist
4206         btstack_linked_list_iterator_remove(&it);
4207         btstack_memory_whitelist_entry_free(entry);
4208     }
4209 }
4210 
4211 /**
4212  * @brief Auto Connection Establishment - Stop Connecting to device
4213  * @param address_typ
4214  * @param address
4215  * @returns 0 if ok
4216  */
4217 int gap_auto_connection_stop(bd_addr_type_t address_type, bd_addr_t address){
4218     hci_remove_from_whitelist(address_type, address);
4219     hci_run();
4220     return 0;
4221 }
4222 
4223 /**
4224  * @brief Auto Connection Establishment - Stop everything
4225  * @note  Convenience function to stop all active auto connection attempts
4226  */
4227 void gap_auto_connection_stop_all(void){
4228     btstack_linked_list_iterator_t it;
4229     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
4230     while (btstack_linked_list_iterator_has_next(&it)){
4231         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
4232         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
4233             // remove from controller if already present
4234             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
4235             continue;
4236         }
4237         // directly remove entry from whitelist
4238         btstack_linked_list_iterator_remove(&it);
4239         btstack_memory_whitelist_entry_free(entry);
4240     }
4241     hci_run();
4242 }
4243 #endif
4244 #endif
4245 
4246 #ifdef ENABLE_CLASSIC
4247 /**
4248  * @brief Set Extended Inquiry Response data
4249  * @param eir_data size 240 bytes, is not copied make sure memory is accessible during stack startup
4250  * @note has to be done before stack starts up
4251  */
4252 void gap_set_extended_inquiry_response(const uint8_t * data){
4253     hci_stack->eir_data = data;
4254 }
4255 
4256 /**
4257  * @brief Start GAP Classic Inquiry
4258  * @param duration in 1.28s units
4259  * @return 0 if ok
4260  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
4261  */
4262 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
4263     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
4264     if (duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN || duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX){
4265         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
4266     }
4267     hci_stack->inquiry_state = duration_in_1280ms_units;
4268     hci_run();
4269     return 0;
4270 }
4271 
4272 /**
4273  * @brief Stop GAP Classic Inquiry
4274  * @returns 0 if ok
4275  */
4276 int gap_inquiry_stop(void){
4277     if (hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN || hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX) {
4278         // emit inquiry complete event, before it even started
4279         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
4280         hci_emit_event(event, sizeof(event), 1);
4281         return 0;
4282     }
4283     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
4284     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
4285     hci_run();
4286     return 0;
4287 }
4288 
4289 
4290 /**
4291  * @brief Remote Name Request
4292  * @param addr
4293  * @param page_scan_repetition_mode
4294  * @param clock_offset only used when bit 15 is set
4295  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
4296  */
4297 int gap_remote_name_request(bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
4298     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
4299     memcpy(hci_stack->remote_name_addr, addr, 6);
4300     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
4301     hci_stack->remote_name_clock_offset = clock_offset;
4302     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
4303     hci_run();
4304     return 0;
4305 }
4306 
4307 static int gap_pairing_set_state_and_run(bd_addr_t addr, uint8_t state){
4308     hci_stack->gap_pairing_state = state;
4309     memcpy(hci_stack->gap_pairing_addr, addr, 6);
4310     hci_run();
4311     return 0;
4312 }
4313 
4314 /**
4315  * @brief Legacy Pairing Pin Code Response
4316  * @param addr
4317  * @param pin
4318  * @return 0 if ok
4319  */
4320 int gap_pin_code_response(bd_addr_t addr, const char * pin){
4321     if (hci_stack->gap_pairing_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
4322     hci_stack->gap_pairing_pin = pin;
4323     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
4324 }
4325 
4326 /**
4327  * @brief Abort Legacy Pairing
4328  * @param addr
4329  * @param pin
4330  * @return 0 if ok
4331  */
4332 int gap_pin_code_negative(bd_addr_t addr){
4333     if (hci_stack->gap_pairing_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
4334     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
4335 }
4336 
4337 /**
4338  * @brief SSP Passkey Response
4339  * @param addr
4340  * @param passkey
4341  * @return 0 if ok
4342  */
4343 int gap_ssp_passkey_response(bd_addr_t addr, uint32_t passkey){
4344     if (hci_stack->gap_pairing_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
4345     hci_stack->gap_pairing_passkey = passkey;
4346     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
4347 }
4348 
4349 /**
4350  * @brief Abort SSP Passkey Entry/Pairing
4351  * @param addr
4352  * @param pin
4353  * @return 0 if ok
4354  */
4355 int gap_ssp_passkey_negative(bd_addr_t addr){
4356     if (hci_stack->gap_pairing_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
4357     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
4358 }
4359 
4360 /**
4361  * @brief Accept SSP Numeric Comparison
4362  * @param addr
4363  * @param passkey
4364  * @return 0 if ok
4365  */
4366 int gap_ssp_confirmation_response(bd_addr_t addr){
4367     if (hci_stack->gap_pairing_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
4368     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
4369 }
4370 
4371 /**
4372  * @brief Abort SSP Numeric Comparison/Pairing
4373  * @param addr
4374  * @param pin
4375  * @return 0 if ok
4376  */
4377 int gap_ssp_confirmation_negative(bd_addr_t addr){
4378     if (hci_stack->gap_pairing_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
4379     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
4380 }
4381 
4382 /**
4383  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
4384  * @param inquiry_mode see bluetooth_defines.h
4385  */
4386 void hci_set_inquiry_mode(inquiry_mode_t mode){
4387     hci_stack->inquiry_mode = mode;
4388 }
4389 
4390 /**
4391  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
4392  */
4393 void hci_set_sco_voice_setting(uint16_t voice_setting){
4394     hci_stack->sco_voice_setting = voice_setting;
4395 }
4396 
4397 /**
4398  * @brief Get SCO Voice Setting
4399  * @return current voice setting
4400  */
4401 uint16_t hci_get_sco_voice_setting(void){
4402     return hci_stack->sco_voice_setting;
4403 }
4404 
4405 /** @brief Get SCO packet length for current SCO Voice setting
4406  *  @note  Using SCO packets of the exact length is required for USB transfer
4407  *  @return Length of SCO packets in bytes (not audio frames)
4408  */
4409 int hci_get_sco_packet_length(void){
4410     // see Core Spec for H2 USB Transfer.
4411     if (hci_stack->sco_voice_setting & 0x0020) return 51;
4412     return 27;
4413 }
4414 #endif
4415 
4416 
4417 HCI_STATE hci_get_state(void){
4418     return hci_stack->state;
4419 }
4420 
4421 
4422 /**
4423  * @brief Set callback for Bluetooth Hardware Error
4424  */
4425 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
4426     hci_stack->hardware_error_callback = fn;
4427 }
4428 
4429 void hci_disconnect_all(void){
4430     btstack_linked_list_iterator_t it;
4431     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
4432     while (btstack_linked_list_iterator_has_next(&it)){
4433         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
4434         if (con->state == SENT_DISCONNECT) continue;
4435         con->state = SEND_DISCONNECT;
4436     }
4437     hci_run();
4438 }
4439 
4440 uint16_t hci_get_manufacturer(void){
4441     return hci_stack->manufacturer;
4442 }
4443