xref: /btstack/src/hci.c (revision e8c8828ea55576056ea633aba7da6f4f10c12e02)
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 /*
39  *  hci.c
40  *
41  *  Created by Matthias Ringwald on 4/29/09.
42  *
43  */
44 
45 #include "btstack_config.h"
46 
47 
48 #ifdef ENABLE_CLASSIC
49 #ifdef HAVE_EMBEDDED_TICK
50 #include "btstack_run_loop_embedded.h"
51 #endif
52 #endif
53 
54 #ifdef HAVE_PLATFORM_IPHONE_OS
55 #include "../port/ios/src/btstack_control_iphone.h"
56 #endif
57 
58 #ifdef ENABLE_BLE
59 #include "gap.h"
60 #endif
61 
62 #include <stdarg.h>
63 #include <string.h>
64 #include <stdio.h>
65 #include <inttypes.h>
66 
67 #include "btstack_debug.h"
68 #include "btstack_event.h"
69 #include "btstack_linked_list.h"
70 #include "btstack_memory.h"
71 #include "gap.h"
72 #include "hci.h"
73 #include "hci_cmd.h"
74 #include "hci_dump.h"
75 
76 
77 #define HCI_CONNECTION_TIMEOUT_MS 10000
78 #define HCI_RESET_RESEND_TIMEOUT_MS 200
79 
80 // prototypes
81 #ifdef ENABLE_CLASSIC
82 static void hci_update_scan_enable(void);
83 static void hci_emit_discoverable_enabled(uint8_t enabled);
84 static int  hci_local_ssp_activated(void);
85 static int  hci_remote_ssp_supported(hci_con_handle_t con_handle);
86 static void hci_notify_if_sco_can_send_now(void);
87 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status);
88 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection);
89 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level);
90 static void hci_connection_timeout_handler(btstack_timer_source_t *timer);
91 static void hci_connection_timestamp(hci_connection_t *connection);
92 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn);
93 #endif
94 static int  hci_power_control_on(void);
95 static void hci_power_control_off(void);
96 static void hci_state_reset(void);
97 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason);
98 static void hci_emit_nr_connections_changed(void);
99 static void hci_emit_hci_open_failed(void);
100 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status);
101 static void hci_emit_event(uint8_t * event, uint16_t size, int dump);
102 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size);
103 static void hci_run(void);
104 static int  hci_is_le_connection(hci_connection_t * connection);
105 static int  hci_number_free_acl_slots_for_connection_type( bd_addr_type_t address_type);
106 
107 #ifdef ENABLE_BLE
108 #ifdef ENABLE_LE_CENTRAL
109 // called from test/ble_client/advertising_data_parser.c
110 void le_handle_advertisement_report(uint8_t *packet, int size);
111 static void hci_remove_from_whitelist(bd_addr_type_t address_type, bd_addr_t address);
112 #endif
113 #endif
114 
115 // the STACK is here
116 #ifndef HAVE_MALLOC
117 static hci_stack_t   hci_stack_static;
118 #endif
119 static hci_stack_t * hci_stack = NULL;
120 
121 #ifdef ENABLE_CLASSIC
122 // test helper
123 static uint8_t disable_l2cap_timeouts = 0;
124 #endif
125 
126 /**
127  * create connection for given address
128  *
129  * @return connection OR NULL, if no memory left
130  */
131 static hci_connection_t * create_connection_for_bd_addr_and_type(bd_addr_t addr, bd_addr_type_t addr_type){
132     log_info("create_connection_for_addr %s, type %x", bd_addr_to_str(addr), addr_type);
133     hci_connection_t * conn = btstack_memory_hci_connection_get();
134     if (!conn) return NULL;
135     memset(conn, 0, sizeof(hci_connection_t));
136     bd_addr_copy(conn->address, addr);
137     conn->address_type = addr_type;
138     conn->con_handle = 0xffff;
139     conn->authentication_flags = AUTH_FLAGS_NONE;
140     conn->bonding_flags = 0;
141     conn->requested_security_level = LEVEL_0;
142 #ifdef ENABLE_CLASSIC
143     btstack_run_loop_set_timer_handler(&conn->timeout, hci_connection_timeout_handler);
144     btstack_run_loop_set_timer_context(&conn->timeout, conn);
145     hci_connection_timestamp(conn);
146 #endif
147     conn->acl_recombination_length = 0;
148     conn->acl_recombination_pos = 0;
149     conn->num_acl_packets_sent = 0;
150     conn->num_sco_packets_sent = 0;
151     conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
152     btstack_linked_list_add(&hci_stack->connections, (btstack_linked_item_t *) conn);
153     return conn;
154 }
155 
156 
157 /**
158  * get le connection parameter range
159 *
160  * @return le connection parameter range struct
161  */
162 void gap_get_connection_parameter_range(le_connection_parameter_range_t * range){
163     *range = hci_stack->le_connection_parameter_range;
164 }
165 
166 /**
167  * set le connection parameter range
168  *
169  */
170 
171 void gap_set_connection_parameter_range(le_connection_parameter_range_t *range){
172     hci_stack->le_connection_parameter_range = *range;
173 }
174 
175 /**
176  * get hci connections iterator
177  *
178  * @return hci connections iterator
179  */
180 
181 void hci_connections_get_iterator(btstack_linked_list_iterator_t *it){
182     btstack_linked_list_iterator_init(it, &hci_stack->connections);
183 }
184 
185 /**
186  * get connection for a given handle
187  *
188  * @return connection OR NULL, if not found
189  */
190 hci_connection_t * hci_connection_for_handle(hci_con_handle_t con_handle){
191     btstack_linked_list_iterator_t it;
192     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
193     while (btstack_linked_list_iterator_has_next(&it)){
194         hci_connection_t * item = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
195         if ( item->con_handle == con_handle ) {
196             return item;
197         }
198     }
199     return NULL;
200 }
201 
202 /**
203  * get connection for given address
204  *
205  * @return connection OR NULL, if not found
206  */
207 hci_connection_t * hci_connection_for_bd_addr_and_type(bd_addr_t  addr, bd_addr_type_t addr_type){
208     btstack_linked_list_iterator_t it;
209     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
210     while (btstack_linked_list_iterator_has_next(&it)){
211         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
212         if (connection->address_type != addr_type)  continue;
213         if (memcmp(addr, connection->address, 6) != 0) continue;
214         return connection;
215     }
216     return NULL;
217 }
218 
219 
220 #ifdef ENABLE_CLASSIC
221 
222 static void hci_connection_timeout_handler(btstack_timer_source_t *timer){
223     hci_connection_t * connection = (hci_connection_t *) btstack_run_loop_get_timer_context(timer);
224 #ifdef HAVE_EMBEDDED_TICK
225     if (btstack_run_loop_embedded_get_ticks() > connection->timestamp + btstack_run_loop_embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
226         // connections might be timed out
227         hci_emit_l2cap_check_timeout(connection);
228     }
229 #else
230     if (btstack_run_loop_get_time_ms() > connection->timestamp + HCI_CONNECTION_TIMEOUT_MS){
231         // connections might be timed out
232         hci_emit_l2cap_check_timeout(connection);
233     }
234 #endif
235 }
236 
237 static void hci_connection_timestamp(hci_connection_t *connection){
238 #ifdef HAVE_EMBEDDED_TICK
239     connection->timestamp = btstack_run_loop_embedded_get_ticks();
240 #else
241     connection->timestamp = btstack_run_loop_get_time_ms();
242 #endif
243 }
244 
245 inline static void connectionSetAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
246     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags | flags);
247 }
248 
249 
250 inline static void connectionClearAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
251     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags & ~flags);
252 }
253 
254 /**
255  * add authentication flags and reset timer
256  * @note: assumes classic connection
257  * @note: bd_addr is passed in as litle endian uint8_t * as it is called from parsing packets
258  */
259 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
260     bd_addr_t addr;
261     reverse_bd_addr(bd_addr, addr);
262     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
263     if (conn) {
264         connectionSetAuthenticationFlags(conn, flags);
265         hci_connection_timestamp(conn);
266     }
267 }
268 
269 int  hci_authentication_active_for_handle(hci_con_handle_t handle){
270     hci_connection_t * conn = hci_connection_for_handle(handle);
271     if (!conn) return 0;
272     if (conn->authentication_flags & LEGACY_PAIRING_ACTIVE) return 1;
273     if (conn->authentication_flags & SSP_PAIRING_ACTIVE) return 1;
274     return 0;
275 }
276 
277 void gap_drop_link_key_for_bd_addr(bd_addr_t addr){
278     if (!hci_stack->link_key_db) return;
279     log_info("gap_drop_link_key_for_bd_addr: %s", bd_addr_to_str(addr));
280     hci_stack->link_key_db->delete_link_key(addr);
281 }
282 
283 void gap_store_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t type){
284     if (!hci_stack->link_key_db) return;
285     log_info("gap_store_link_key_for_bd_addr: %s, type %u", bd_addr_to_str(addr), type);
286     hci_stack->link_key_db->put_link_key(addr, link_key, type);
287 }
288 #endif
289 
290 static int hci_is_le_connection(hci_connection_t * connection){
291     return  connection->address_type == BD_ADDR_TYPE_LE_PUBLIC ||
292     connection->address_type == BD_ADDR_TYPE_LE_RANDOM;
293 }
294 
295 /**
296  * count connections
297  */
298 static int nr_hci_connections(void){
299     int count = 0;
300     btstack_linked_item_t *it;
301     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next, count++);
302     return count;
303 }
304 
305 static int hci_number_free_acl_slots_for_connection_type(bd_addr_type_t address_type){
306 
307     unsigned int num_packets_sent_classic = 0;
308     unsigned int num_packets_sent_le = 0;
309 
310     btstack_linked_item_t *it;
311     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
312         hci_connection_t * connection = (hci_connection_t *) it;
313         if (connection->address_type == BD_ADDR_TYPE_CLASSIC){
314             num_packets_sent_classic += connection->num_acl_packets_sent;
315         } else {
316             num_packets_sent_le += connection->num_acl_packets_sent;
317         }
318     }
319     log_debug("ACL classic buffers: %u used of %u", num_packets_sent_classic, hci_stack->acl_packets_total_num);
320     int free_slots_classic = hci_stack->acl_packets_total_num - num_packets_sent_classic;
321     int free_slots_le = 0;
322 
323     if (free_slots_classic < 0){
324         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);
325         return 0;
326     }
327 
328     if (hci_stack->le_acl_packets_total_num){
329         // if we have LE slots, they are used
330         free_slots_le = hci_stack->le_acl_packets_total_num - num_packets_sent_le;
331         if (free_slots_le < 0){
332             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);
333             return 0;
334         }
335     } else {
336         // otherwise, classic slots are used for LE, too
337         free_slots_classic -= num_packets_sent_le;
338         if (free_slots_classic < 0){
339             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);
340             return 0;
341         }
342     }
343 
344     switch (address_type){
345         case BD_ADDR_TYPE_UNKNOWN:
346             log_error("hci_number_free_acl_slots: unknown address type");
347             return 0;
348 
349         case BD_ADDR_TYPE_CLASSIC:
350             return free_slots_classic;
351 
352         default:
353            if (hci_stack->le_acl_packets_total_num){
354                return free_slots_le;
355            }
356            return free_slots_classic;
357     }
358 }
359 
360 int hci_number_free_acl_slots_for_handle(hci_con_handle_t con_handle){
361     // get connection type
362     hci_connection_t * connection = hci_connection_for_handle(con_handle);
363     if (!connection){
364         log_error("hci_number_free_acl_slots: handle 0x%04x not in connection list", con_handle);
365         return 0;
366     }
367     return hci_number_free_acl_slots_for_connection_type(connection->address_type);
368 }
369 
370 #ifdef ENABLE_CLASSIC
371 static int hci_number_free_sco_slots(void){
372     unsigned int num_sco_packets_sent  = 0;
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         num_sco_packets_sent += connection->num_sco_packets_sent;
377     }
378     if (num_sco_packets_sent > hci_stack->sco_packets_total_num){
379         log_info("hci_number_free_sco_slots:packets (%u) > total packets (%u)", num_sco_packets_sent, hci_stack->sco_packets_total_num);
380         return 0;
381     }
382     // log_info("hci_number_free_sco_slots u", handle, num_sco_packets_sent);
383     return hci_stack->sco_packets_total_num - num_sco_packets_sent;
384 }
385 #endif
386 
387 // new functions replacing hci_can_send_packet_now[_using_packet_buffer]
388 int hci_can_send_command_packet_now(void){
389     if (hci_stack->hci_packet_buffer_reserved) return 0;
390 
391     // check for async hci transport implementations
392     if (hci_stack->hci_transport->can_send_packet_now){
393         if (!hci_stack->hci_transport->can_send_packet_now(HCI_COMMAND_DATA_PACKET)){
394             return 0;
395         }
396     }
397 
398     return hci_stack->num_cmd_packets > 0;
399 }
400 
401 static int hci_transport_can_send_prepared_packet_now(uint8_t packet_type){
402     // check for async hci transport implementations
403     if (!hci_stack->hci_transport->can_send_packet_now) return 1;
404     return hci_stack->hci_transport->can_send_packet_now(packet_type);
405 }
406 
407 static int hci_can_send_prepared_acl_packet_for_address_type(bd_addr_type_t address_type){
408     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
409     return hci_number_free_acl_slots_for_connection_type(address_type) > 0;
410 }
411 
412 int hci_can_send_acl_le_packet_now(void){
413     if (hci_stack->hci_packet_buffer_reserved) return 0;
414     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_LE_PUBLIC);
415 }
416 
417 int hci_can_send_prepared_acl_packet_now(hci_con_handle_t con_handle) {
418     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
419     return hci_number_free_acl_slots_for_handle(con_handle) > 0;
420 }
421 
422 int hci_can_send_acl_packet_now(hci_con_handle_t con_handle){
423     if (hci_stack->hci_packet_buffer_reserved) return 0;
424     return hci_can_send_prepared_acl_packet_now(con_handle);
425 }
426 
427 #ifdef ENABLE_CLASSIC
428 int hci_can_send_acl_classic_packet_now(void){
429     if (hci_stack->hci_packet_buffer_reserved) return 0;
430     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_CLASSIC);
431 }
432 
433 int hci_can_send_prepared_sco_packet_now(void){
434     if (!hci_transport_can_send_prepared_packet_now(HCI_SCO_DATA_PACKET)) return 0;
435     if (!hci_stack->synchronous_flow_control_enabled) return 1;
436     return hci_number_free_sco_slots() > 0;
437 }
438 
439 int hci_can_send_sco_packet_now(void){
440     if (hci_stack->hci_packet_buffer_reserved) return 0;
441     return hci_can_send_prepared_sco_packet_now();
442 }
443 
444 void hci_request_sco_can_send_now_event(void){
445     hci_stack->sco_waiting_for_can_send_now = 1;
446     hci_notify_if_sco_can_send_now();
447 }
448 #endif
449 
450 // used for internal checks in l2cap.c
451 int hci_is_packet_buffer_reserved(void){
452     return hci_stack->hci_packet_buffer_reserved;
453 }
454 
455 // reserves outgoing packet buffer. @returns 1 if successful
456 int hci_reserve_packet_buffer(void){
457     if (hci_stack->hci_packet_buffer_reserved) {
458         log_error("hci_reserve_packet_buffer called but buffer already reserved");
459         return 0;
460     }
461     hci_stack->hci_packet_buffer_reserved = 1;
462     return 1;
463 }
464 
465 void hci_release_packet_buffer(void){
466     hci_stack->hci_packet_buffer_reserved = 0;
467 }
468 
469 // assumption: synchronous implementations don't provide can_send_packet_now as they don't keep the buffer after the call
470 static int hci_transport_synchronous(void){
471     return hci_stack->hci_transport->can_send_packet_now == NULL;
472 }
473 
474 static int hci_send_acl_packet_fragments(hci_connection_t *connection){
475 
476     // 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);
477 
478     // max ACL data packet length depends on connection type (LE vs. Classic) and available buffers
479     uint16_t max_acl_data_packet_length = hci_stack->acl_data_packet_length;
480     if (hci_is_le_connection(connection) && hci_stack->le_data_packets_length > 0){
481         max_acl_data_packet_length = hci_stack->le_data_packets_length;
482     }
483 
484     // testing: reduce buffer to minimum
485     // max_acl_data_packet_length = 52;
486 
487     log_debug("hci_send_acl_packet_fragments entered");
488 
489     int err;
490     // multiple packets could be send on a synchronous HCI transport
491     while (1){
492 
493         log_debug("hci_send_acl_packet_fragments loop entered");
494 
495         // get current data
496         const uint16_t acl_header_pos = hci_stack->acl_fragmentation_pos - 4;
497         int current_acl_data_packet_length = hci_stack->acl_fragmentation_total_size - hci_stack->acl_fragmentation_pos;
498         int more_fragments = 0;
499 
500         // if ACL packet is larger than Bluetooth packet buffer, only send max_acl_data_packet_length
501         if (current_acl_data_packet_length > max_acl_data_packet_length){
502             more_fragments = 1;
503             current_acl_data_packet_length = max_acl_data_packet_length;
504         }
505 
506         // copy handle_and_flags if not first fragment and update packet boundary flags to be 01 (continuing fragmnent)
507         if (acl_header_pos > 0){
508             uint16_t handle_and_flags = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
509             handle_and_flags = (handle_and_flags & 0xcfff) | (1 << 12);
510             little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos, handle_and_flags);
511         }
512 
513         // update header len
514         little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos + 2, current_acl_data_packet_length);
515 
516         // count packet
517         connection->num_acl_packets_sent++;
518         log_debug("hci_send_acl_packet_fragments loop before send (more fragments %d)", more_fragments);
519 
520         // update state for next fragment (if any) as "transport done" might be sent during send_packet already
521         if (more_fragments){
522             // update start of next fragment to send
523             hci_stack->acl_fragmentation_pos += current_acl_data_packet_length;
524         } else {
525             // done
526             hci_stack->acl_fragmentation_pos = 0;
527             hci_stack->acl_fragmentation_total_size = 0;
528         }
529 
530         // send packet
531         uint8_t * packet = &hci_stack->hci_packet_buffer[acl_header_pos];
532         const int size = current_acl_data_packet_length + 4;
533         hci_dump_packet(HCI_ACL_DATA_PACKET, 0, packet, size);
534         err = hci_stack->hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
535 
536         log_debug("hci_send_acl_packet_fragments loop after send (more fragments %d)", more_fragments);
537 
538         // done yet?
539         if (!more_fragments) break;
540 
541         // can send more?
542         if (!hci_can_send_prepared_acl_packet_now(connection->con_handle)) return err;
543     }
544 
545     log_debug("hci_send_acl_packet_fragments loop over");
546 
547     // release buffer now for synchronous transport
548     if (hci_transport_synchronous()){
549         hci_release_packet_buffer();
550         // notify upper stack that it might be possible to send again
551         uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
552         hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
553     }
554 
555     return err;
556 }
557 
558 // pre: caller has reserved the packet buffer
559 int hci_send_acl_packet_buffer(int size){
560 
561     // log_info("hci_send_acl_packet_buffer size %u", size);
562 
563     if (!hci_stack->hci_packet_buffer_reserved) {
564         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
565         return 0;
566     }
567 
568     uint8_t * packet = hci_stack->hci_packet_buffer;
569     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
570 
571     // check for free places on Bluetooth module
572     if (!hci_can_send_prepared_acl_packet_now(con_handle)) {
573         log_error("hci_send_acl_packet_buffer called but no free ACL buffers on controller");
574         hci_release_packet_buffer();
575         return BTSTACK_ACL_BUFFERS_FULL;
576     }
577 
578     hci_connection_t *connection = hci_connection_for_handle( con_handle);
579     if (!connection) {
580         log_error("hci_send_acl_packet_buffer called but no connection for handle 0x%04x", con_handle);
581         hci_release_packet_buffer();
582         return 0;
583     }
584 
585 #ifdef ENABLE_CLASSIC
586     hci_connection_timestamp(connection);
587 #endif
588 
589     // hci_dump_packet( HCI_ACL_DATA_PACKET, 0, packet, size);
590 
591     // setup data
592     hci_stack->acl_fragmentation_total_size = size;
593     hci_stack->acl_fragmentation_pos = 4;   // start of L2CAP packet
594 
595     return hci_send_acl_packet_fragments(connection);
596 }
597 
598 #ifdef ENABLE_CLASSIC
599 // pre: caller has reserved the packet buffer
600 int hci_send_sco_packet_buffer(int size){
601 
602     // log_info("hci_send_acl_packet_buffer size %u", size);
603 
604     if (!hci_stack->hci_packet_buffer_reserved) {
605         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
606         return 0;
607     }
608 
609     uint8_t * packet = hci_stack->hci_packet_buffer;
610 
611     // skip checks in loopback mode
612     if (!hci_stack->loopback_mode){
613         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);   // same for ACL and SCO
614 
615         // check for free places on Bluetooth module
616         if (!hci_can_send_prepared_sco_packet_now()) {
617             log_error("hci_send_sco_packet_buffer called but no free ACL buffers on controller");
618             hci_release_packet_buffer();
619             return BTSTACK_ACL_BUFFERS_FULL;
620         }
621 
622         // track send packet in connection struct
623         hci_connection_t *connection = hci_connection_for_handle( con_handle);
624         if (!connection) {
625             log_error("hci_send_sco_packet_buffer called but no connection for handle 0x%04x", con_handle);
626             hci_release_packet_buffer();
627             return 0;
628         }
629         connection->num_sco_packets_sent++;
630     }
631 
632     hci_dump_packet( HCI_SCO_DATA_PACKET, 0, packet, size);
633     int err = hci_stack->hci_transport->send_packet(HCI_SCO_DATA_PACKET, packet, size);
634 
635     if (hci_transport_synchronous()){
636         hci_release_packet_buffer();
637         // notify upper stack that it might be possible to send again
638         uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
639         hci_emit_event(&event[0], sizeof(event), 0);    // don't dump
640     }
641 
642     return err;
643 }
644 #endif
645 
646 static void acl_handler(uint8_t *packet, int size){
647 
648     // log_info("acl_handler: size %u", size);
649 
650     // get info
651     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
652     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
653     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
654     uint16_t acl_length         = READ_ACL_LENGTH(packet);
655 
656     // ignore non-registered handle
657     if (!conn){
658         log_error( "hci.c: acl_handler called with non-registered handle %u!" , con_handle);
659         return;
660     }
661 
662     // assert packet is complete
663     if (acl_length + 4 != size){
664         log_error("hci.c: acl_handler called with ACL packet of wrong size %d, expected %u => dropping packet", size, acl_length + 4);
665         return;
666     }
667 
668 #ifdef ENABLE_CLASSIC
669     // update idle timestamp
670     hci_connection_timestamp(conn);
671 #endif
672 
673     // handle different packet types
674     switch (acl_flags & 0x03) {
675 
676         case 0x01: // continuation fragment
677 
678             // sanity checks
679             if (conn->acl_recombination_pos == 0) {
680                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x", con_handle);
681                 return;
682             }
683             if (conn->acl_recombination_pos + acl_length > 4 + HCI_ACL_BUFFER_SIZE){
684                 log_error( "ACL Cont Fragment to large: combined packet %u > buffer size %u for handle 0x%02x",
685                     conn->acl_recombination_pos + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
686                 conn->acl_recombination_pos = 0;
687                 return;
688             }
689 
690             // append fragment payload (header already stored)
691             memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE + conn->acl_recombination_pos], &packet[4], acl_length );
692             conn->acl_recombination_pos += acl_length;
693 
694             // log_error( "ACL Cont Fragment: acl_len %u, combined_len %u, l2cap_len %u", acl_length,
695             //        conn->acl_recombination_pos, conn->acl_recombination_length);
696 
697             // forward complete L2CAP packet if complete.
698             if (conn->acl_recombination_pos >= conn->acl_recombination_length + 4 + 4){ // pos already incl. ACL header
699                 hci_emit_acl_packet(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], conn->acl_recombination_pos);
700                 // reset recombination buffer
701                 conn->acl_recombination_length = 0;
702                 conn->acl_recombination_pos = 0;
703             }
704             break;
705 
706         case 0x02: { // first fragment
707 
708             // sanity check
709             if (conn->acl_recombination_pos) {
710                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x, dropping stale fragments", con_handle);
711                 conn->acl_recombination_pos = 0;
712             }
713 
714             // peek into L2CAP packet!
715             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
716 
717             // log_info( "ACL First Fragment: acl_len %u, l2cap_len %u", acl_length, l2cap_length);
718 
719             // compare fragment size to L2CAP packet size
720             if (acl_length >= l2cap_length + 4){
721                 // forward fragment as L2CAP packet
722                 hci_emit_acl_packet(packet, acl_length + 4);
723             } else {
724 
725                 if (acl_length > HCI_ACL_BUFFER_SIZE){
726                     log_error( "ACL First Fragment to large: fragment %u > buffer size %u for handle 0x%02x",
727                         4 + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
728                     return;
729                 }
730 
731                 // store first fragment and tweak acl length for complete package
732                 memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], packet, acl_length + 4);
733                 conn->acl_recombination_pos    = acl_length + 4;
734                 conn->acl_recombination_length = l2cap_length;
735                 little_endian_store_16(conn->acl_recombination_buffer, HCI_INCOMING_PRE_BUFFER_SIZE + 2, l2cap_length +4);
736             }
737             break;
738 
739         }
740         default:
741             log_error( "hci.c: acl_handler called with invalid packet boundary flags %u", acl_flags & 0x03);
742             return;
743     }
744 
745     // execute main loop
746     hci_run();
747 }
748 
749 static void hci_shutdown_connection(hci_connection_t *conn){
750     log_info("Connection closed: handle 0x%x, %s", conn->con_handle, bd_addr_to_str(conn->address));
751 
752     btstack_run_loop_remove_timer(&conn->timeout);
753 
754     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
755     btstack_memory_hci_connection_free( conn );
756 
757     // now it's gone
758     hci_emit_nr_connections_changed();
759 }
760 
761 #ifdef ENABLE_CLASSIC
762 
763 static const uint16_t packet_type_sizes[] = {
764     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
765     HCI_ACL_DH1_SIZE, 0, 0, 0,
766     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
767     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
768 };
769 static const uint8_t  packet_type_feature_requirement_bit[] = {
770      0, // 3 slot packets
771      1, // 5 slot packets
772     25, // EDR 2 mpbs
773     26, // EDR 3 mbps
774     39, // 3 slot EDR packts
775     40, // 5 slot EDR packet
776 };
777 static const uint16_t packet_type_feature_packet_mask[] = {
778     0x0f00, // 3 slot packets
779     0xf000, // 5 slot packets
780     0x1102, // EDR 2 mpbs
781     0x2204, // EDR 3 mbps
782     0x0300, // 3 slot EDR packts
783     0x3000, // 5 slot EDR packet
784 };
785 
786 static uint16_t hci_acl_packet_types_for_buffer_size_and_local_features(uint16_t buffer_size, uint8_t * local_supported_features){
787     // enable packet types based on size
788     uint16_t packet_types = 0;
789     unsigned int i;
790     for (i=0;i<16;i++){
791         if (packet_type_sizes[i] == 0) continue;
792         if (packet_type_sizes[i] <= buffer_size){
793             packet_types |= 1 << i;
794         }
795     }
796     // disable packet types due to missing local supported features
797     for (i=0;i<sizeof(packet_type_feature_requirement_bit);i++){
798         unsigned int bit_idx = packet_type_feature_requirement_bit[i];
799         int feature_set = (local_supported_features[bit_idx >> 3] & (1<<(bit_idx & 7))) != 0;
800         if (feature_set) continue;
801         log_info("Features bit %02u is not set, removing packet types 0x%04x", bit_idx, packet_type_feature_packet_mask[i]);
802         packet_types &= ~packet_type_feature_packet_mask[i];
803     }
804     // flip bits for "may not be used"
805     packet_types ^= 0x3306;
806     return packet_types;
807 }
808 
809 uint16_t hci_usable_acl_packet_types(void){
810     return hci_stack->packet_types;
811 }
812 #endif
813 
814 uint8_t* hci_get_outgoing_packet_buffer(void){
815     // hci packet buffer is >= acl data packet length
816     return hci_stack->hci_packet_buffer;
817 }
818 
819 uint16_t hci_max_acl_data_packet_length(void){
820     return hci_stack->acl_data_packet_length;
821 }
822 
823 #ifdef ENABLE_CLASSIC
824 int hci_extended_sco_link_supported(void){
825     // No. 31, byte 3, bit 7
826     return (hci_stack->local_supported_features[3] & (1 << 7)) != 0;
827 }
828 #endif
829 
830 int hci_non_flushable_packet_boundary_flag_supported(void){
831     // No. 54, byte 6, bit 6
832     return (hci_stack->local_supported_features[6] & (1 << 6)) != 0;
833 }
834 
835 static int gap_ssp_supported(void){
836     // No. 51, byte 6, bit 3
837     return (hci_stack->local_supported_features[6] & (1 << 3)) != 0;
838 }
839 
840 static int hci_classic_supported(void){
841 #ifdef ENABLE_CLASSIC
842     // No. 37, byte 4, bit 5, = No BR/EDR Support
843     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
844 #else
845     return 0;
846 #endif
847 }
848 
849 static int hci_le_supported(void){
850 #ifdef ENABLE_BLE
851     // No. 37, byte 4, bit 6 = LE Supported (Controller)
852     return (hci_stack->local_supported_features[4] & (1 << 6)) != 0;
853 #else
854     return 0;
855 #endif
856 }
857 
858 // get addr type and address used in advertisement packets
859 void gap_advertisements_get_address(uint8_t * addr_type, bd_addr_t  addr){
860     *addr_type = hci_stack->adv_addr_type;
861     if (hci_stack->adv_addr_type){
862         memcpy(addr, hci_stack->adv_address, 6);
863     } else {
864         memcpy(addr, hci_stack->local_bd_addr, 6);
865     }
866 }
867 
868 #ifdef ENABLE_BLE
869 #ifdef ENABLE_LE_CENTRAL
870 void le_handle_advertisement_report(uint8_t *packet, int size){
871 
872     UNUSED(size);
873 
874     int offset = 3;
875     int num_reports = packet[offset];
876     offset += 1;
877 
878     int i;
879     // log_info("HCI: handle adv report with num reports: %d", num_reports);
880     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
881     for (i=0; i<num_reports;i++){
882         uint8_t data_length = packet[offset + 8];
883         uint8_t event_size = 10 + data_length;
884         int pos = 0;
885         event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
886         event[pos++] = event_size;
887         memcpy(&event[pos], &packet[offset], 1+1+6); // event type + address type + address
888         offset += 8;
889         pos += 8;
890         event[pos++] = packet[offset + 1 + data_length]; // rssi
891         event[pos++] = packet[offset++]; //data_length;
892         memcpy(&event[pos], &packet[offset], data_length);
893         pos += data_length;
894         offset += data_length + 1; // rssi
895         hci_emit_event(event, pos, 1);
896     }
897 }
898 #endif
899 #endif
900 
901 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
902 
903 static uint32_t hci_transport_uart_get_main_baud_rate(void){
904     if (!hci_stack->config) return 0;
905     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
906     // Limit baud rate for Broadcom chipsets to 3 mbps
907     if (hci_stack->manufacturer == COMPANY_ID_BROADCOM_CORPORATION && baud_rate > 3000000){
908         baud_rate = 3000000;
909     }
910     return baud_rate;
911 }
912 
913 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
914     UNUSED(ds);
915 
916     switch (hci_stack->substate){
917         case HCI_INIT_W4_SEND_RESET:
918             log_info("Resend HCI Reset");
919             hci_stack->substate = HCI_INIT_SEND_RESET;
920             hci_stack->num_cmd_packets = 1;
921             hci_run();
922             break;
923         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
924             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
925             if (hci_stack->hci_transport->reset_link){
926                 hci_stack->hci_transport->reset_link();
927             }
928             // no break - explicit fallthrough to HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT
929         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
930             log_info("Resend HCI Reset - CSR Warm Boot");
931             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
932             hci_stack->num_cmd_packets = 1;
933             hci_run();
934             break;
935         case HCI_INIT_W4_SEND_BAUD_CHANGE:
936             if (hci_stack->hci_transport->set_baudrate){
937                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
938                 log_info("Local baud rate change to %"PRIu32"(timeout handler)", baud_rate);
939                 hci_stack->hci_transport->set_baudrate(baud_rate);
940             }
941             // For CSR, HCI Reset is sent on new baud rate
942             if (hci_stack->manufacturer == COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
943                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
944                 hci_run();
945             }
946             break;
947         default:
948             break;
949     }
950 }
951 #endif
952 
953 static void hci_initializing_next_state(void){
954     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
955 }
956 
957 // assumption: hci_can_send_command_packet_now() == true
958 static void hci_initializing_run(void){
959     log_debug("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
960     switch (hci_stack->substate){
961         case HCI_INIT_SEND_RESET:
962             hci_state_reset();
963 
964 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
965             // prepare reset if command complete not received in 100ms
966             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
967             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
968             btstack_run_loop_add_timer(&hci_stack->timeout);
969 #endif
970             // send command
971             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
972             hci_send_cmd(&hci_reset);
973             break;
974         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
975             hci_send_cmd(&hci_read_local_version_information);
976             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
977             break;
978         case HCI_INIT_SEND_READ_LOCAL_NAME:
979             hci_send_cmd(&hci_read_local_name);
980             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
981             break;
982 
983 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
984         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
985             hci_state_reset();
986             // prepare reset if command complete not received in 100ms
987             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
988             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
989             btstack_run_loop_add_timer(&hci_stack->timeout);
990             // send command
991             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
992             hci_send_cmd(&hci_reset);
993             break;
994         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
995             hci_state_reset();
996             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
997             hci_send_cmd(&hci_reset);
998             break;
999         case HCI_INIT_SEND_BAUD_CHANGE: {
1000             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1001             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1002             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1003             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1004             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1005             // STLC25000D: baudrate change happens within 0.5 s after command was send,
1006             // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1007             if (hci_stack->manufacturer == COMPANY_ID_ST_MICROELECTRONICS){
1008                 btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1009                 btstack_run_loop_add_timer(&hci_stack->timeout);
1010             }
1011             break;
1012         }
1013         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1014             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1015             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1016             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1017             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1018             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1019             break;
1020         }
1021         case HCI_INIT_CUSTOM_INIT:
1022             // Custom initialization
1023             if (hci_stack->chipset && hci_stack->chipset->next_command){
1024                 int valid_cmd = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1025                 if (valid_cmd){
1026                     int size = 3 + hci_stack->hci_packet_buffer[2];
1027                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1028                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1029                     switch (valid_cmd) {
1030                         case 1:
1031                         default:
1032                             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1033                             break;
1034                         case 2: // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1035                             log_info("CSR Warm Boot");
1036                             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1037                             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1038                             btstack_run_loop_add_timer(&hci_stack->timeout);
1039                             if (hci_stack->manufacturer == COMPANY_ID_CAMBRIDGE_SILICON_RADIO
1040                                 && hci_stack->config
1041                                 && hci_stack->chipset
1042                                 // && hci_stack->chipset->set_baudrate_command -- there's no such command
1043                                 && hci_stack->hci_transport->set_baudrate
1044                                 && hci_transport_uart_get_main_baud_rate()){
1045                                 hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1046                             } else {
1047                                hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1048                             }
1049                             break;
1050                     }
1051                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1052                     break;
1053                 }
1054                 log_info("Init script done");
1055 
1056                 // Init script download causes baud rate to reset on Broadcom chipsets, restore UART baud rate if needed
1057                 if (hci_stack->manufacturer == COMPANY_ID_BROADCOM_CORPORATION){
1058                     int need_baud_change = hci_stack->config
1059                         && hci_stack->chipset
1060                         && hci_stack->chipset->set_baudrate_command
1061                         && hci_stack->hci_transport->set_baudrate
1062                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1063                     if (need_baud_change) {
1064                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1065                         log_info("Local baud rate change to %"PRIu32" after init script (bcm)", baud_rate);
1066                         hci_stack->hci_transport->set_baudrate(baud_rate);
1067                     }
1068                 }
1069             }
1070             // otherwise continue
1071             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1072             hci_send_cmd(&hci_read_local_supported_commands);
1073             break;
1074         case HCI_INIT_SET_BD_ADDR:
1075             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1076             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1077             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1078             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1079             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1080             break;
1081 #endif
1082 
1083         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1084             log_info("Resend hci_read_local_supported_commands after CSR Warm Boot double reset");
1085             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1086             hci_send_cmd(&hci_read_local_supported_commands);
1087             break;
1088         case HCI_INIT_READ_BD_ADDR:
1089             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1090             hci_send_cmd(&hci_read_bd_addr);
1091             break;
1092         case HCI_INIT_READ_BUFFER_SIZE:
1093             hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1094             hci_send_cmd(&hci_read_buffer_size);
1095             break;
1096         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1097             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1098             hci_send_cmd(&hci_read_local_supported_features);
1099             break;
1100         case HCI_INIT_SET_EVENT_MASK:
1101             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1102             if (hci_le_supported()){
1103                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x3FFFFFFF);
1104             } else {
1105                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1106                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x1FFFFFFF);
1107             }
1108             break;
1109 #ifdef ENABLE_CLASSIC
1110         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1111             hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1112             hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1113             break;
1114         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1115             hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1116             hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1117             break;
1118         case HCI_INIT_WRITE_CLASS_OF_DEVICE:
1119             hci_stack->substate = HCI_INIT_W4_WRITE_CLASS_OF_DEVICE;
1120             hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1121             break;
1122         case HCI_INIT_WRITE_LOCAL_NAME:
1123             hci_stack->substate = HCI_INIT_W4_WRITE_LOCAL_NAME;
1124             if (hci_stack->local_name){
1125                 hci_send_cmd(&hci_write_local_name, hci_stack->local_name);
1126             } else {
1127                 char local_name[8+17+1];
1128                 // BTstack 11:22:33:44:55:66
1129                 memcpy(local_name, "BTstack ", 8);
1130                 memcpy(&local_name[8], bd_addr_to_str(hci_stack->local_bd_addr), 17);   // strlen(bd_addr_to_str(...)) = 17
1131                 local_name[8+17] = '\0';
1132                 log_info("---> Name %s", local_name);
1133                 hci_send_cmd(&hci_write_local_name, local_name);
1134             }
1135             break;
1136         case HCI_INIT_WRITE_EIR_DATA:
1137             hci_stack->substate = HCI_INIT_W4_WRITE_EIR_DATA;
1138             hci_send_cmd(&hci_write_extended_inquiry_response, 0, hci_stack->eir_data);
1139             break;
1140         case HCI_INIT_WRITE_INQUIRY_MODE:
1141             hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1142             hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1143             break;
1144         case HCI_INIT_WRITE_SCAN_ENABLE:
1145             hci_send_cmd(&hci_write_scan_enable, (hci_stack->connectable << 1) | hci_stack->discoverable); // page scan
1146             hci_stack->substate = HCI_INIT_W4_WRITE_SCAN_ENABLE;
1147             break;
1148         // only sent if ENABLE_SCO_OVER_HCI is defined
1149         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1150             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1151             hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1152             break;
1153         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1154             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1155             hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1156             break;
1157 #endif
1158 #ifdef ENABLE_BLE
1159         // LE INIT
1160         case HCI_INIT_LE_READ_BUFFER_SIZE:
1161             hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1162             hci_send_cmd(&hci_le_read_buffer_size);
1163             break;
1164         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1165             // LE Supported Host = 1, Simultaneous Host = 0
1166             hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1167             hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1168             break;
1169         case HCI_INIT_READ_WHITE_LIST_SIZE:
1170             hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1171             hci_send_cmd(&hci_le_read_white_list_size);
1172             break;
1173         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1174             // LE Scan Parameters: active scanning, 300 ms interval, 30 ms window, public address, accept all advs
1175             hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1176             hci_send_cmd(&hci_le_set_scan_parameters, 1, 0x1e0, 0x30, 0, 0);
1177             break;
1178 #endif
1179         default:
1180             return;
1181     }
1182 }
1183 
1184 static void hci_init_done(void){
1185     // done. tell the app
1186     log_info("hci_init_done -> HCI_STATE_WORKING");
1187     hci_stack->state = HCI_STATE_WORKING;
1188     hci_emit_state();
1189     hci_run();
1190 }
1191 
1192 static void hci_initializing_event_handler(uint8_t * packet, uint16_t size){
1193     UNUSED(size);
1194 
1195     uint8_t command_completed = 0;
1196 
1197     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1198         uint16_t opcode = little_endian_read_16(packet,3);
1199         if (opcode == hci_stack->last_cmd_opcode){
1200             command_completed = 1;
1201             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1202         } else {
1203             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1204         }
1205     }
1206 
1207     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1208         uint8_t  status = packet[2];
1209         uint16_t opcode = little_endian_read_16(packet,4);
1210         if (opcode == hci_stack->last_cmd_opcode){
1211             if (status){
1212                 command_completed = 1;
1213                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1214             } else {
1215                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1216             }
1217         } else {
1218             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1219         }
1220     }
1221 
1222 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1223 
1224     // Vendor == CSR
1225     if (hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT && hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC){
1226         // TODO: track actual command
1227         command_completed = 1;
1228     }
1229 
1230     // Vendor == Toshiba
1231     if (hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE && hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC){
1232         // TODO: track actual command
1233         command_completed = 1;
1234     }
1235 
1236     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1237     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1238     //
1239     // HCI Reset
1240     // Timeout 100 ms
1241     // HCI Reset
1242     // Command Complete Reset
1243     // HCI Read Local Version Information
1244     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1245     // hang...
1246     //
1247     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1248     if (!command_completed
1249             && hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE
1250             && hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION){
1251 
1252         uint16_t opcode = little_endian_read_16(packet,3);
1253         if (opcode == hci_reset.opcode){
1254             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1255             return;
1256         }
1257     }
1258 
1259     // CSR & H5
1260     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1261     if (!command_completed
1262             && hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE
1263             && hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS){
1264 
1265         uint16_t opcode = little_endian_read_16(packet,3);
1266         if (opcode == hci_reset.opcode){
1267             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1268             return;
1269         }
1270     }
1271 
1272     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1273     // fix: Correct substate and behave as command below
1274     if (command_completed){
1275         switch (hci_stack->substate){
1276             case HCI_INIT_SEND_RESET:
1277                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1278                 break;
1279             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1280                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1281                 break;
1282             default:
1283                 break;
1284         }
1285     }
1286 
1287 #endif
1288 
1289     if (!command_completed) return;
1290 
1291     int need_baud_change = 0;
1292     int need_addr_change = 0;
1293 
1294 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1295     need_baud_change = hci_stack->config
1296                         && hci_stack->chipset
1297                         && hci_stack->chipset->set_baudrate_command
1298                         && hci_stack->hci_transport->set_baudrate
1299                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1300 
1301     need_addr_change = hci_stack->custom_bd_addr_set
1302                         && hci_stack->chipset
1303                         && hci_stack->chipset->set_bd_addr_command;
1304 #endif
1305 
1306     switch(hci_stack->substate){
1307 
1308 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1309         case HCI_INIT_SEND_RESET:
1310             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1311             // fix: just correct substate and behave as command below
1312             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1313             btstack_run_loop_remove_timer(&hci_stack->timeout);
1314             break;
1315         case HCI_INIT_W4_SEND_RESET:
1316             btstack_run_loop_remove_timer(&hci_stack->timeout);
1317             break;
1318         case HCI_INIT_W4_SEND_READ_LOCAL_NAME:
1319             log_info("Received local name, need baud change %d", need_baud_change);
1320             if (need_baud_change){
1321                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE;
1322                 return;
1323             }
1324             // skip baud change
1325             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1326             return;
1327         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1328             // for STLC2500D, baud rate change already happened.
1329             // for others, baud rate gets changed now
1330             if ((hci_stack->manufacturer != COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1331                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1332                 log_info("Local baud rate change to %"PRIu32"(w4_send_baud_change)", baud_rate);
1333                 hci_stack->hci_transport->set_baudrate(baud_rate);
1334             }
1335             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1336             return;
1337         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1338             btstack_run_loop_remove_timer(&hci_stack->timeout);
1339             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1340             return;
1341         case HCI_INIT_W4_CUSTOM_INIT:
1342             // repeat custom init
1343             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1344             return;
1345 #else
1346         case HCI_INIT_W4_SEND_RESET:
1347             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1348             return ;
1349 #endif
1350 
1351         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1352             if (need_baud_change && hci_stack->manufacturer == COMPANY_ID_BROADCOM_CORPORATION){
1353                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1354                 return;
1355             }
1356             if (need_addr_change){
1357                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1358                 return;
1359             }
1360             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1361             return;
1362 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1363         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1364             if (need_baud_change){
1365                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1366                 log_info("Local baud rate change to %"PRIu32"(w4_send_baud_change_bcm))", baud_rate);
1367                 hci_stack->hci_transport->set_baudrate(baud_rate);
1368             }
1369             if (need_addr_change){
1370                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1371                 return;
1372             }
1373             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1374             return;
1375         case HCI_INIT_W4_SET_BD_ADDR:
1376             // for STLC2500D, bd addr change only gets active after sending reset command
1377             if (hci_stack->manufacturer == COMPANY_ID_ST_MICROELECTRONICS){
1378                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1379                 return;
1380             }
1381             // skipping st warm boot
1382             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1383             return;
1384         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
1385             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1386             return;
1387 #endif
1388         case HCI_INIT_W4_READ_BD_ADDR:
1389             // only read buffer size if supported
1390             if (hci_stack->local_supported_commands[0] & 0x01) {
1391                 hci_stack->substate = HCI_INIT_READ_BUFFER_SIZE;
1392                 return;
1393             }
1394             // skipping read buffer size
1395             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES;
1396             return;
1397         case HCI_INIT_W4_SET_EVENT_MASK:
1398             // skip Classic init commands for LE only chipsets
1399             if (!hci_classic_supported()){
1400                 if (hci_le_supported()){
1401                     hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE; // skip all classic command
1402                     return;
1403                 } else {
1404                     log_error("Neither BR/EDR nor LE supported");
1405                     hci_init_done();
1406                     return;
1407                 }
1408             }
1409             if (!gap_ssp_supported()){
1410                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1411                 return;
1412             }
1413             break;
1414         case HCI_INIT_W4_LE_READ_BUFFER_SIZE:
1415             // skip write le host if not supported (e.g. on LE only EM9301)
1416             if (hci_stack->local_supported_commands[0] & 0x02) break;
1417             hci_stack->substate = HCI_INIT_LE_SET_SCAN_PARAMETERS;
1418             return;
1419         case HCI_INIT_W4_WRITE_LOCAL_NAME:
1420             // skip write eir data if no eir data set
1421             if (hci_stack->eir_data) break;
1422             hci_stack->substate = HCI_INIT_WRITE_INQUIRY_MODE;
1423             return;
1424 
1425 #ifdef ENABLE_SCO_OVER_HCI
1426         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1427             // skip write synchronous flow control if not supported
1428             if (hci_stack->local_supported_commands[0] & 0x04) break;
1429             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1430             // explicit fall through to reduce repetitions
1431 
1432         case HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1433             // skip write default erroneous data reporting if not supported
1434             if (hci_stack->local_supported_commands[0] & 0x08) break;
1435             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1436             // explicit fall through to reduce repetitions
1437 
1438         case HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1439             if (!hci_le_supported()){
1440                 // SKIP LE init for Classic only configuration
1441                 hci_init_done();
1442                 return;
1443             }
1444             break;
1445 #else
1446         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1447             if (!hci_le_supported()){
1448                 // SKIP LE init for Classic only configuration
1449                 hci_init_done();
1450                 return;
1451             }
1452 #endif
1453             break;
1454         // Response to command before init done state -> init done
1455         case (HCI_INIT_DONE-1):
1456             hci_init_done();
1457             return;
1458 
1459         default:
1460             break;
1461     }
1462     hci_initializing_next_state();
1463 }
1464 
1465 static void event_handler(uint8_t *packet, int size){
1466 
1467     uint16_t event_length = packet[1];
1468 
1469     // assert packet is complete
1470     if (size != event_length + 2){
1471         log_error("hci.c: event_handler called with event packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
1472         return;
1473     }
1474 
1475     bd_addr_t addr;
1476     bd_addr_type_t addr_type;
1477     uint8_t link_type;
1478     hci_con_handle_t handle;
1479     hci_connection_t * conn;
1480     int i;
1481 
1482     // warnings
1483     (void) link_type;
1484 
1485     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
1486 
1487     switch (hci_event_packet_get_type(packet)) {
1488 
1489         case HCI_EVENT_COMMAND_COMPLETE:
1490             // get num cmd packets - limit to 1 to reduce complexity
1491             hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
1492 
1493             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_name)){
1494                 if (packet[5]) break;
1495                 // terminate, name 248 chars
1496                 packet[6+248] = 0;
1497                 log_info("local name: %s", &packet[6]);
1498             }
1499             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_buffer_size)){
1500                 // from offset 5
1501                 // status
1502                 // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
1503                 hci_stack->acl_data_packet_length = little_endian_read_16(packet, 6);
1504                 hci_stack->sco_data_packet_length = packet[8];
1505                 hci_stack->acl_packets_total_num  = little_endian_read_16(packet, 9);
1506                 hci_stack->sco_packets_total_num  = little_endian_read_16(packet, 11);
1507 
1508                 if (hci_stack->state == HCI_STATE_INITIALIZING){
1509                     // determine usable ACL payload size
1510                     if (HCI_ACL_PAYLOAD_SIZE < hci_stack->acl_data_packet_length){
1511                         hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
1512                     }
1513                     log_info("hci_read_buffer_size: acl used size %u, count %u / sco size %u, count %u",
1514                              hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
1515                              hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
1516                 }
1517             }
1518 #ifdef ENABLE_BLE
1519             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_buffer_size)){
1520                 hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
1521                 hci_stack->le_acl_packets_total_num  = packet[8];
1522                     // determine usable ACL payload size
1523                     if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
1524                         hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
1525                     }
1526                 log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
1527             }
1528 #ifdef ENABLE_LE_CENTRAL
1529             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_white_list_size)){
1530                 hci_stack->le_whitelist_capacity = little_endian_read_16(packet, 6);
1531                 log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
1532             }
1533 #endif
1534 #endif
1535             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_bd_addr)) {
1536                 reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1],
1537 				hci_stack->local_bd_addr);
1538                 log_info("Local Address, Status: 0x%02x: Addr: %s",
1539                     packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE], bd_addr_to_str(hci_stack->local_bd_addr));
1540 #ifdef ENABLE_CLASSIC
1541                 if (hci_stack->link_key_db){
1542                     hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
1543                 }
1544 #endif
1545             }
1546 #ifdef ENABLE_CLASSIC
1547             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)){
1548                 hci_emit_discoverable_enabled(hci_stack->discoverable);
1549             }
1550 #endif
1551 
1552             // Note: HCI init checks
1553             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_supported_features)){
1554                 memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 8);
1555 
1556 #ifdef ENABLE_CLASSIC
1557                 // determine usable ACL packet types based on host buffer size and supported features
1558                 hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
1559                 log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
1560 #endif
1561                 // Classic/LE
1562                 log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
1563             }
1564             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_version_information)){
1565                 // hci_stack->hci_version    = little_endian_read_16(packet, 4);
1566                 // hci_stack->hci_revision   = little_endian_read_16(packet, 6);
1567                 // hci_stack->lmp_version    = little_endian_read_16(packet, 8);
1568                 hci_stack->manufacturer   = little_endian_read_16(packet, 10);
1569                 // hci_stack->lmp_subversion = little_endian_read_16(packet, 12);
1570                 log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
1571             }
1572             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_supported_commands)){
1573                 hci_stack->local_supported_commands[0] =
1574                     (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+14] & 0x80) >> 7 |  // bit 0 = Octet 14, bit 7
1575                     (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+24] & 0x40) >> 5 |  // bit 1 = Octet 24, bit 6
1576                     (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+10] & 0x10) >> 2 |  // bit 2 = Octet 10, bit 4
1577                     (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+18] & 0x08);        // bit 3 = Octet 18, bit 3
1578                     log_info("Local supported commands summary 0x%02x", hci_stack->local_supported_commands[0]);
1579             }
1580 #ifdef ENABLE_CLASSIC
1581             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_synchronous_flow_control_enable)){
1582                 if (packet[5] == 0){
1583                     hci_stack->synchronous_flow_control_enabled = 1;
1584                 }
1585             }
1586 #endif
1587             break;
1588 
1589         case HCI_EVENT_COMMAND_STATUS:
1590             // get num cmd packets - limit to 1 to reduce complexity
1591             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
1592             break;
1593 
1594         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
1595             int offset = 3;
1596             for (i=0; i<packet[2];i++){
1597                 handle = little_endian_read_16(packet, offset);
1598                 offset += 2;
1599                 uint16_t num_packets = little_endian_read_16(packet, offset);
1600                 offset += 2;
1601 
1602                 conn = hci_connection_for_handle(handle);
1603                 if (!conn){
1604                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
1605                     continue;
1606                 }
1607 
1608                 if (conn->address_type == BD_ADDR_TYPE_SCO){
1609 #ifdef ENABLE_CLASSIC
1610                     if (conn->num_sco_packets_sent >= num_packets){
1611                         conn->num_sco_packets_sent -= num_packets;
1612                     } else {
1613                         log_error("hci_number_completed_packets, more sco slots freed then sent.");
1614                         conn->num_sco_packets_sent = 0;
1615                     }
1616                     hci_notify_if_sco_can_send_now();
1617 #endif
1618                 } else {
1619                     if (conn->num_acl_packets_sent >= num_packets){
1620                         conn->num_acl_packets_sent -= num_packets;
1621                     } else {
1622                         log_error("hci_number_completed_packets, more acl slots freed then sent.");
1623                         conn->num_acl_packets_sent = 0;
1624                     }
1625                 }
1626                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_acl_packets_sent);
1627             }
1628             break;
1629         }
1630 
1631 #ifdef ENABLE_CLASSIC
1632         case HCI_EVENT_CONNECTION_REQUEST:
1633             reverse_bd_addr(&packet[2], addr);
1634             // TODO: eval COD 8-10
1635             link_type = packet[11];
1636             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), link_type);
1637             addr_type = link_type == 1 ? BD_ADDR_TYPE_CLASSIC : BD_ADDR_TYPE_SCO;
1638             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
1639             if (!conn) {
1640                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
1641             }
1642             if (!conn) {
1643                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
1644                 hci_stack->decline_reason = 0x0d;
1645                 bd_addr_copy(hci_stack->decline_addr, addr);
1646                 break;
1647             }
1648             conn->role  = HCI_ROLE_SLAVE;
1649             conn->state = RECEIVED_CONNECTION_REQUEST;
1650             // store info about eSCO
1651             if (link_type == 0x02){
1652                 conn->remote_supported_feature_eSCO = 1;
1653             }
1654             hci_run();
1655             break;
1656 
1657         case HCI_EVENT_CONNECTION_COMPLETE:
1658             // Connection management
1659             reverse_bd_addr(&packet[5], addr);
1660             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
1661             addr_type = BD_ADDR_TYPE_CLASSIC;
1662             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
1663             if (conn) {
1664                 if (!packet[2]){
1665                     conn->state = OPEN;
1666                     conn->con_handle = little_endian_read_16(packet, 3);
1667                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES;
1668 
1669                     // restart timer
1670                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
1671                     btstack_run_loop_add_timer(&conn->timeout);
1672 
1673                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
1674 
1675                     hci_emit_nr_connections_changed();
1676                 } else {
1677                     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
1678                     uint8_t status = packet[2];
1679                     bd_addr_t bd_address;
1680                     memcpy(&bd_address, conn->address, 6);
1681 
1682                     // connection failed, remove entry
1683                     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1684                     btstack_memory_hci_connection_free( conn );
1685 
1686                     // notify client if dedicated bonding
1687                     if (notify_dedicated_bonding_failed){
1688                         log_info("hci notify_dedicated_bonding_failed");
1689                         hci_emit_dedicated_bonding_result(bd_address, status);
1690                     }
1691 
1692                     // if authentication error, also delete link key
1693                     if (packet[2] == 0x05) {
1694                         gap_drop_link_key_for_bd_addr(addr);
1695                     }
1696                 }
1697             }
1698             break;
1699 
1700         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
1701             reverse_bd_addr(&packet[5], addr);
1702             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
1703             if (packet[2]){
1704                 // connection failed
1705                 break;
1706             }
1707             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
1708             if (!conn) {
1709                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
1710             }
1711             if (!conn) {
1712                 break;
1713             }
1714             conn->state = OPEN;
1715             conn->con_handle = little_endian_read_16(packet, 3);
1716             break;
1717 
1718         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
1719             handle = little_endian_read_16(packet, 3);
1720             conn = hci_connection_for_handle(handle);
1721             if (!conn) break;
1722             if (!packet[2]){
1723                 uint8_t * features = &packet[5];
1724                 if (features[6] & (1 << 3)){
1725                     conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP;
1726                 }
1727                 if (features[3] & (1<<7)){
1728                     conn->remote_supported_feature_eSCO = 1;
1729                 }
1730             }
1731             conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
1732             log_info("HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE, bonding flags %x, eSCO %u", conn->bonding_flags, conn->remote_supported_feature_eSCO);
1733             if (conn->bonding_flags & BONDING_DEDICATED){
1734                 conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
1735             }
1736             break;
1737 
1738         case HCI_EVENT_LINK_KEY_REQUEST:
1739             log_info("HCI_EVENT_LINK_KEY_REQUEST");
1740             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_REQUEST);
1741             // non-bondable mode: link key negative reply will be sent by HANDLE_LINK_KEY_REQUEST
1742             if (hci_stack->bondable && !hci_stack->link_key_db) break;
1743             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], HANDLE_LINK_KEY_REQUEST);
1744             hci_run();
1745             // request handled by hci_run() as HANDLE_LINK_KEY_REQUEST gets set
1746             return;
1747 
1748         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
1749             reverse_bd_addr(&packet[2], addr);
1750             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
1751             if (!conn) break;
1752             conn->authentication_flags |= RECV_LINK_KEY_NOTIFICATION;
1753             link_key_type_t link_key_type = (link_key_type_t)packet[24];
1754             // Change Connection Encryption keeps link key type
1755             if (link_key_type != CHANGED_COMBINATION_KEY){
1756                 conn->link_key_type = link_key_type;
1757             }
1758             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
1759             // still forward event to allow dismiss of pairing dialog
1760             break;
1761         }
1762 
1763         case HCI_EVENT_PIN_CODE_REQUEST:
1764             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], LEGACY_PAIRING_ACTIVE);
1765             // non-bondable mode: pin code negative reply will be sent
1766             if (!hci_stack->bondable){
1767                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], DENY_PIN_CODE_REQUEST);
1768                 hci_run();
1769                 return;
1770             }
1771             // PIN CODE REQUEST means the link key request didn't succee -> delete stored link key
1772             if (!hci_stack->link_key_db) break;
1773             hci_event_pin_code_request_get_bd_addr(packet, addr);
1774             hci_stack->link_key_db->delete_link_key(addr);
1775             break;
1776 
1777         case HCI_EVENT_IO_CAPABILITY_REQUEST:
1778             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_IO_CAPABILITIES_REQUEST);
1779             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_IO_CAPABILITIES_REPLY);
1780             break;
1781 
1782         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
1783             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
1784             if (!hci_stack->ssp_auto_accept) break;
1785             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_CONFIRM_REPLY);
1786             break;
1787 
1788         case HCI_EVENT_USER_PASSKEY_REQUEST:
1789             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
1790             if (!hci_stack->ssp_auto_accept) break;
1791             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_PASSKEY_REPLY);
1792             break;
1793 #endif
1794 
1795         case HCI_EVENT_ENCRYPTION_CHANGE:
1796             handle = little_endian_read_16(packet, 3);
1797             conn = hci_connection_for_handle(handle);
1798             if (!conn) break;
1799             if (packet[2] == 0) {
1800                 if (packet[5]){
1801                     conn->authentication_flags |= CONNECTION_ENCRYPTED;
1802                 } else {
1803                     conn->authentication_flags &= ~CONNECTION_ENCRYPTED;
1804                 }
1805             }
1806 #ifdef ENABLE_CLASSIC
1807             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
1808 #endif
1809             break;
1810 
1811 #ifdef ENABLE_CLASSIC
1812         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
1813             handle = little_endian_read_16(packet, 3);
1814             conn = hci_connection_for_handle(handle);
1815             if (!conn) break;
1816 
1817             // dedicated bonding: send result and disconnect
1818             if (conn->bonding_flags & BONDING_DEDICATED){
1819                 conn->bonding_flags &= ~BONDING_DEDICATED;
1820                 conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
1821                 conn->bonding_status = packet[2];
1822                 break;
1823             }
1824 
1825             if (packet[2] == 0 && gap_security_level_for_link_key_type(conn->link_key_type) >= conn->requested_security_level){
1826                 // link key sufficient for requested security
1827                 conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
1828                 break;
1829             }
1830             // not enough
1831             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
1832             break;
1833 #endif
1834 
1835         // HCI_EVENT_DISCONNECTION_COMPLETE
1836         // has been split, to first notify stack before shutting connection down
1837         // see end of function, too.
1838         case HCI_EVENT_DISCONNECTION_COMPLETE:
1839             if (packet[2]) break;   // status != 0
1840             handle = little_endian_read_16(packet, 3);
1841             // drop outgoing ACL fragments if it is for closed connection
1842             if (hci_stack->acl_fragmentation_total_size > 0) {
1843                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
1844                     log_info("hci: drop fragmented ACL data for closed connection");
1845                      hci_stack->acl_fragmentation_total_size = 0;
1846                      hci_stack->acl_fragmentation_pos = 0;
1847                 }
1848             }
1849 
1850             // re-enable advertisements for le connections if active
1851             conn = hci_connection_for_handle(handle);
1852             if (!conn) break;
1853 #ifdef ENABLE_BLE
1854 #ifdef ENABLE_LE_PERIPHERAL
1855             if (hci_is_le_connection(conn) && hci_stack->le_advertisements_enabled){
1856                 hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
1857             }
1858 #endif
1859 #endif
1860             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
1861             break;
1862 
1863         case HCI_EVENT_HARDWARE_ERROR:
1864             log_error("Hardware Error: 0x%02x", packet[2]);
1865             if (hci_stack->hardware_error_callback){
1866                 (*hci_stack->hardware_error_callback)(packet[2]);
1867             } else {
1868                 // if no special requests, just reboot stack
1869                 hci_power_control_off();
1870                 hci_power_control_on();
1871             }
1872             break;
1873 
1874 #ifdef ENABLE_CLASSIC
1875         case HCI_EVENT_ROLE_CHANGE:
1876             if (packet[2]) break;   // status != 0
1877             handle = little_endian_read_16(packet, 3);
1878             conn = hci_connection_for_handle(handle);
1879             if (!conn) break;       // no conn
1880             conn->role = packet[9];
1881             break;
1882 #endif
1883 
1884         case HCI_EVENT_TRANSPORT_PACKET_SENT:
1885             // release packet buffer only for asynchronous transport and if there are not further fragements
1886             if (hci_transport_synchronous()) {
1887                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
1888                 return; // instead of break: to avoid re-entering hci_run()
1889             }
1890             if (hci_stack->acl_fragmentation_total_size) break;
1891             hci_release_packet_buffer();
1892 
1893             // L2CAP receives this event via the hci_emit_event below
1894 
1895 #ifdef ENABLE_CLASSIC
1896             // For SCO, we do the can_send_now_check here
1897             hci_notify_if_sco_can_send_now();
1898 #endif
1899             break;
1900 
1901 #ifdef ENABLE_CLASSIC
1902         case HCI_EVENT_SCO_CAN_SEND_NOW:
1903             // For SCO, we do the can_send_now_check here
1904             hci_notify_if_sco_can_send_now();
1905             return;
1906 #endif
1907 
1908 #ifdef ENABLE_BLE
1909         case HCI_EVENT_LE_META:
1910             switch (packet[2]){
1911 #ifdef ENABLE_LE_CENTRAL
1912                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
1913                     // log_info("advertising report received");
1914                     if (hci_stack->le_scanning_state != LE_SCANNING) break;
1915                     le_handle_advertisement_report(packet, size);
1916                     break;
1917 #endif
1918                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
1919                     // Connection management
1920                     reverse_bd_addr(&packet[8], addr);
1921                     addr_type = (bd_addr_type_t)packet[7];
1922                     log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
1923                     conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
1924 #ifdef ENABLE_LE_CENTRAL
1925                     // if auto-connect, remove from whitelist in both roles
1926                     if (hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST){
1927                         hci_remove_from_whitelist(addr_type, addr);
1928                     }
1929                     // handle error: error is reported only to the initiator -> outgoing connection
1930                     if (packet[3]){
1931                         // outgoing connection establishment is done
1932                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
1933                         // remove entry
1934                         if (conn){
1935                             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1936                             btstack_memory_hci_connection_free( conn );
1937                         }
1938                         break;
1939                     }
1940 #endif
1941                     // on success, both hosts receive connection complete event
1942                     if (packet[6] == HCI_ROLE_MASTER){
1943 #ifdef ENABLE_LE_CENTRAL
1944                         // if we're master, it was an outgoing connection and we're done with it
1945                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
1946 #endif
1947                     } else {
1948 #ifdef ENABLE_LE_PERIPHERAL
1949                         // if we're slave, it was an incoming connection, advertisements have stopped
1950                         hci_stack->le_advertisements_active = 0;
1951                         // try to re-enable them
1952                         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
1953 #endif
1954                     }
1955                     // LE connections are auto-accepted, so just create a connection if there isn't one already
1956                     if (!conn){
1957                         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
1958                     }
1959                     // no memory, sorry.
1960                     if (!conn){
1961                         break;
1962                     }
1963 
1964                     conn->state = OPEN;
1965                     conn->role  = packet[6];
1966                     conn->con_handle = little_endian_read_16(packet, 4);
1967 
1968                     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
1969 
1970                     // restart timer
1971                     // btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
1972                     // btstack_run_loop_add_timer(&conn->timeout);
1973 
1974                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
1975 
1976                     hci_emit_nr_connections_changed();
1977                     break;
1978 
1979             // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
1980 
1981                 default:
1982                     break;
1983             }
1984             break;
1985 #endif
1986         default:
1987             break;
1988     }
1989 
1990     // handle BT initialization
1991     if (hci_stack->state == HCI_STATE_INITIALIZING){
1992         hci_initializing_event_handler(packet, size);
1993     }
1994 
1995     // help with BT sleep
1996     if (hci_stack->state == HCI_STATE_FALLING_ASLEEP
1997         && hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE
1998         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)){
1999         hci_initializing_next_state();
2000     }
2001 
2002     // notify upper stack
2003 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
2004 
2005     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
2006     if (hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE){
2007         if (!packet[2]){
2008             handle = little_endian_read_16(packet, 3);
2009             hci_connection_t * aConn = hci_connection_for_handle(handle);
2010             if (aConn) {
2011                 uint8_t status = aConn->bonding_status;
2012                 uint16_t flags = aConn->bonding_flags;
2013                 bd_addr_t bd_address;
2014                 memcpy(&bd_address, aConn->address, 6);
2015                 hci_shutdown_connection(aConn);
2016                 // connection struct is gone, don't access anymore
2017                 if (flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
2018                     hci_emit_dedicated_bonding_result(bd_address, status);
2019                 }
2020             }
2021         }
2022     }
2023 
2024 	// execute main loop
2025 	hci_run();
2026 }
2027 
2028 #ifdef ENABLE_CLASSIC
2029 static void sco_handler(uint8_t * packet, uint16_t size){
2030     if (!hci_stack->sco_packet_handler) return;
2031     hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
2032 }
2033 #endif
2034 
2035 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
2036     hci_dump_packet(packet_type, 1, packet, size);
2037     switch (packet_type) {
2038         case HCI_EVENT_PACKET:
2039             event_handler(packet, size);
2040             break;
2041         case HCI_ACL_DATA_PACKET:
2042             acl_handler(packet, size);
2043             break;
2044 #ifdef ENABLE_CLASSIC
2045         case HCI_SCO_DATA_PACKET:
2046             sco_handler(packet, size);
2047             break;
2048 #endif
2049         default:
2050             break;
2051     }
2052 }
2053 
2054 /**
2055  * @brief Add event packet handler.
2056  */
2057 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
2058     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
2059 }
2060 
2061 
2062 /** Register HCI packet handlers */
2063 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
2064     hci_stack->acl_packet_handler = handler;
2065 }
2066 
2067 #ifdef ENABLE_CLASSIC
2068 /**
2069  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
2070  */
2071 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
2072     hci_stack->sco_packet_handler = handler;
2073 }
2074 #endif
2075 
2076 static void hci_state_reset(void){
2077     // no connections yet
2078     hci_stack->connections = NULL;
2079 
2080     // keep discoverable/connectable as this has been requested by the client(s)
2081     // hci_stack->discoverable = 0;
2082     // hci_stack->connectable = 0;
2083     // hci_stack->bondable = 1;
2084 
2085     // buffer is free
2086     hci_stack->hci_packet_buffer_reserved = 0;
2087 
2088     // no pending cmds
2089     hci_stack->decline_reason = 0;
2090     hci_stack->new_scan_enable_value = 0xff;
2091 
2092     // LE
2093 #ifdef ENABLE_LE_PERIPHERAL
2094     hci_stack->adv_addr_type = 0;
2095     hci_stack->le_advertisements_random_address_set = 0;
2096     memset(hci_stack->adv_address, 0, 6);
2097 #endif
2098 #ifdef ENABLE_LE_CENTRAL
2099     hci_stack->le_scanning_state = LE_SCAN_IDLE;
2100     hci_stack->le_scan_type = 0xff;
2101     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2102     hci_stack->le_whitelist = 0;
2103     hci_stack->le_whitelist_capacity = 0;
2104 #endif
2105 
2106     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
2107     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
2108     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
2109     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
2110     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
2111     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
2112 }
2113 
2114 #ifdef ENABLE_CLASSIC
2115 /**
2116  * @brief Configure Bluetooth hardware control. Has to be called before power on.
2117  */
2118 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
2119     // store and open remote device db
2120     hci_stack->link_key_db = link_key_db;
2121     if (hci_stack->link_key_db) {
2122         hci_stack->link_key_db->open();
2123     }
2124 }
2125 #endif
2126 
2127 void hci_init(const hci_transport_t *transport, const void *config){
2128 
2129 #ifdef HAVE_MALLOC
2130     if (!hci_stack) {
2131         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
2132     }
2133 #else
2134     hci_stack = &hci_stack_static;
2135 #endif
2136     memset(hci_stack, 0, sizeof(hci_stack_t));
2137 
2138     // reference to use transport layer implementation
2139     hci_stack->hci_transport = transport;
2140 
2141     // reference to used config
2142     hci_stack->config = config;
2143 
2144     // setup pointer for outgoing packet buffer
2145     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
2146 
2147     // max acl payload size defined in config.h
2148     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
2149 
2150     // register packet handlers with transport
2151     transport->register_packet_handler(&packet_handler);
2152 
2153     hci_stack->state = HCI_STATE_OFF;
2154 
2155     // class of device
2156     hci_stack->class_of_device = 0x007a020c; // Smartphone
2157 
2158     // bondable by default
2159     hci_stack->bondable = 1;
2160 
2161     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
2162     hci_stack->ssp_enable = 1;
2163     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
2164     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
2165     hci_stack->ssp_auto_accept = 1;
2166 
2167     // voice setting - signed 8 bit pcm data with CVSD over the air
2168     hci_stack->sco_voice_setting = 0x40;
2169 
2170     hci_state_reset();
2171 }
2172 
2173 /**
2174  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
2175  */
2176 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
2177     hci_stack->chipset = chipset_driver;
2178 
2179     // reset chipset driver - init is also called on power_up
2180     if (hci_stack->chipset && hci_stack->chipset->init){
2181         hci_stack->chipset->init(hci_stack->config);
2182     }
2183 }
2184 
2185 /**
2186  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
2187  */
2188 void hci_set_control(const btstack_control_t *hardware_control){
2189     // references to used control implementation
2190     hci_stack->control = hardware_control;
2191     // init with transport config
2192     hardware_control->init(hci_stack->config);
2193 }
2194 
2195 void hci_close(void){
2196     // close remote device db
2197     if (hci_stack->link_key_db) {
2198         hci_stack->link_key_db->close();
2199     }
2200 
2201     btstack_linked_list_iterator_t lit;
2202     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
2203     while (btstack_linked_list_iterator_has_next(&lit)){
2204         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
2205         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
2206         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
2207         hci_shutdown_connection(connection);
2208     }
2209 
2210     hci_power_control(HCI_POWER_OFF);
2211 
2212 #ifdef HAVE_MALLOC
2213     free(hci_stack);
2214 #endif
2215     hci_stack = NULL;
2216 }
2217 
2218 #ifdef ENABLE_CLASSIC
2219 void gap_set_class_of_device(uint32_t class_of_device){
2220     hci_stack->class_of_device = class_of_device;
2221 }
2222 
2223 void hci_disable_l2cap_timeout_check(void){
2224     disable_l2cap_timeouts = 1;
2225 }
2226 #endif
2227 
2228 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
2229 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
2230 void hci_set_bd_addr(bd_addr_t addr){
2231     memcpy(hci_stack->custom_bd_addr, addr, 6);
2232     hci_stack->custom_bd_addr_set = 1;
2233 }
2234 #endif
2235 
2236 // State-Module-Driver overview
2237 // state                    module  low-level
2238 // HCI_STATE_OFF             off      close
2239 // HCI_STATE_INITIALIZING,   on       open
2240 // HCI_STATE_WORKING,        on       open
2241 // HCI_STATE_HALTING,        on       open
2242 // HCI_STATE_SLEEPING,    off/sleep   close
2243 // HCI_STATE_FALLING_ASLEEP  on       open
2244 
2245 static int hci_power_control_on(void){
2246 
2247     // power on
2248     int err = 0;
2249     if (hci_stack->control && hci_stack->control->on){
2250         err = (*hci_stack->control->on)();
2251     }
2252     if (err){
2253         log_error( "POWER_ON failed");
2254         hci_emit_hci_open_failed();
2255         return err;
2256     }
2257 
2258     // int chipset driver
2259     if (hci_stack->chipset && hci_stack->chipset->init){
2260         hci_stack->chipset->init(hci_stack->config);
2261     }
2262 
2263     // init transport
2264     if (hci_stack->hci_transport->init){
2265         hci_stack->hci_transport->init(hci_stack->config);
2266     }
2267 
2268     // open transport
2269     err = hci_stack->hci_transport->open();
2270     if (err){
2271         log_error( "HCI_INIT failed, turning Bluetooth off again");
2272         if (hci_stack->control && hci_stack->control->off){
2273             (*hci_stack->control->off)();
2274         }
2275         hci_emit_hci_open_failed();
2276         return err;
2277     }
2278     return 0;
2279 }
2280 
2281 static void hci_power_control_off(void){
2282 
2283     log_info("hci_power_control_off");
2284 
2285     // close low-level device
2286     hci_stack->hci_transport->close();
2287 
2288     log_info("hci_power_control_off - hci_transport closed");
2289 
2290     // power off
2291     if (hci_stack->control && hci_stack->control->off){
2292         (*hci_stack->control->off)();
2293     }
2294 
2295     log_info("hci_power_control_off - control closed");
2296 
2297     hci_stack->state = HCI_STATE_OFF;
2298 }
2299 
2300 static void hci_power_control_sleep(void){
2301 
2302     log_info("hci_power_control_sleep");
2303 
2304 #if 0
2305     // don't close serial port during sleep
2306 
2307     // close low-level device
2308     hci_stack->hci_transport->close(hci_stack->config);
2309 #endif
2310 
2311     // sleep mode
2312     if (hci_stack->control && hci_stack->control->sleep){
2313         (*hci_stack->control->sleep)();
2314     }
2315 
2316     hci_stack->state = HCI_STATE_SLEEPING;
2317 }
2318 
2319 static int hci_power_control_wake(void){
2320 
2321     log_info("hci_power_control_wake");
2322 
2323     // wake on
2324     if (hci_stack->control && hci_stack->control->wake){
2325         (*hci_stack->control->wake)();
2326     }
2327 
2328 #if 0
2329     // open low-level device
2330     int err = hci_stack->hci_transport->open(hci_stack->config);
2331     if (err){
2332         log_error( "HCI_INIT failed, turning Bluetooth off again");
2333         if (hci_stack->control && hci_stack->control->off){
2334             (*hci_stack->control->off)();
2335         }
2336         hci_emit_hci_open_failed();
2337         return err;
2338     }
2339 #endif
2340 
2341     return 0;
2342 }
2343 
2344 static void hci_power_transition_to_initializing(void){
2345     // set up state machine
2346     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
2347     hci_stack->hci_packet_buffer_reserved = 0;
2348     hci_stack->state = HCI_STATE_INITIALIZING;
2349     hci_stack->substate = HCI_INIT_SEND_RESET;
2350 }
2351 
2352 int hci_power_control(HCI_POWER_MODE power_mode){
2353 
2354     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
2355 
2356     int err = 0;
2357     switch (hci_stack->state){
2358 
2359         case HCI_STATE_OFF:
2360             switch (power_mode){
2361                 case HCI_POWER_ON:
2362                     err = hci_power_control_on();
2363                     if (err) {
2364                         log_error("hci_power_control_on() error %d", err);
2365                         return err;
2366                     }
2367                     hci_power_transition_to_initializing();
2368                     break;
2369                 case HCI_POWER_OFF:
2370                     // do nothing
2371                     break;
2372                 case HCI_POWER_SLEEP:
2373                     // do nothing (with SLEEP == OFF)
2374                     break;
2375             }
2376             break;
2377 
2378         case HCI_STATE_INITIALIZING:
2379             switch (power_mode){
2380                 case HCI_POWER_ON:
2381                     // do nothing
2382                     break;
2383                 case HCI_POWER_OFF:
2384                     // no connections yet, just turn it off
2385                     hci_power_control_off();
2386                     break;
2387                 case HCI_POWER_SLEEP:
2388                     // no connections yet, just turn it off
2389                     hci_power_control_sleep();
2390                     break;
2391             }
2392             break;
2393 
2394         case HCI_STATE_WORKING:
2395             switch (power_mode){
2396                 case HCI_POWER_ON:
2397                     // do nothing
2398                     break;
2399                 case HCI_POWER_OFF:
2400                     // see hci_run
2401                     hci_stack->state = HCI_STATE_HALTING;
2402                     break;
2403                 case HCI_POWER_SLEEP:
2404                     // see hci_run
2405                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
2406                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
2407                     break;
2408             }
2409             break;
2410 
2411         case HCI_STATE_HALTING:
2412             switch (power_mode){
2413                 case HCI_POWER_ON:
2414                     hci_power_transition_to_initializing();
2415                     break;
2416                 case HCI_POWER_OFF:
2417                     // do nothing
2418                     break;
2419                 case HCI_POWER_SLEEP:
2420                     // see hci_run
2421                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
2422                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
2423                     break;
2424             }
2425             break;
2426 
2427         case HCI_STATE_FALLING_ASLEEP:
2428             switch (power_mode){
2429                 case HCI_POWER_ON:
2430 
2431 #ifdef HAVE_PLATFORM_IPHONE_OS
2432                     // nothing to do, if H4 supports power management
2433                     if (btstack_control_iphone_power_management_enabled()){
2434                         hci_stack->state = HCI_STATE_INITIALIZING;
2435                         hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;   // init after sleep
2436                         break;
2437                     }
2438 #endif
2439                     hci_power_transition_to_initializing();
2440                     break;
2441                 case HCI_POWER_OFF:
2442                     // see hci_run
2443                     hci_stack->state = HCI_STATE_HALTING;
2444                     break;
2445                 case HCI_POWER_SLEEP:
2446                     // do nothing
2447                     break;
2448             }
2449             break;
2450 
2451         case HCI_STATE_SLEEPING:
2452             switch (power_mode){
2453                 case HCI_POWER_ON:
2454 
2455 #ifdef HAVE_PLATFORM_IPHONE_OS
2456                     // nothing to do, if H4 supports power management
2457                     if (btstack_control_iphone_power_management_enabled()){
2458                         hci_stack->state = HCI_STATE_INITIALIZING;
2459                         hci_stack->substate = HCI_INIT_AFTER_SLEEP;
2460                         hci_update_scan_enable();
2461                         break;
2462                     }
2463 #endif
2464                     err = hci_power_control_wake();
2465                     if (err) return err;
2466                     hci_power_transition_to_initializing();
2467                     break;
2468                 case HCI_POWER_OFF:
2469                     hci_stack->state = HCI_STATE_HALTING;
2470                     break;
2471                 case HCI_POWER_SLEEP:
2472                     // do nothing
2473                     break;
2474             }
2475             break;
2476     }
2477 
2478     // create internal event
2479 	hci_emit_state();
2480 
2481 	// trigger next/first action
2482 	hci_run();
2483 
2484     return 0;
2485 }
2486 
2487 
2488 #ifdef ENABLE_CLASSIC
2489 
2490 static void hci_update_scan_enable(void){
2491     // 2 = page scan, 1 = inq scan
2492     hci_stack->new_scan_enable_value  = hci_stack->connectable << 1 | hci_stack->discoverable;
2493     hci_run();
2494 }
2495 
2496 void gap_discoverable_control(uint8_t enable){
2497     if (enable) enable = 1; // normalize argument
2498 
2499     if (hci_stack->discoverable == enable){
2500         hci_emit_discoverable_enabled(hci_stack->discoverable);
2501         return;
2502     }
2503 
2504     hci_stack->discoverable = enable;
2505     hci_update_scan_enable();
2506 }
2507 
2508 void gap_connectable_control(uint8_t enable){
2509     if (enable) enable = 1; // normalize argument
2510 
2511     // don't emit event
2512     if (hci_stack->connectable == enable) return;
2513 
2514     hci_stack->connectable = enable;
2515     hci_update_scan_enable();
2516 }
2517 #endif
2518 
2519 void gap_local_bd_addr(bd_addr_t address_buffer){
2520     memcpy(address_buffer, hci_stack->local_bd_addr, 6);
2521 }
2522 
2523 static void hci_run(void){
2524 
2525     // log_info("hci_run: entered");
2526     btstack_linked_item_t * it;
2527 
2528     // send continuation fragments first, as they block the prepared packet buffer
2529     if (hci_stack->acl_fragmentation_total_size > 0) {
2530         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
2531         hci_connection_t *connection = hci_connection_for_handle(con_handle);
2532         if (connection) {
2533             if (hci_can_send_prepared_acl_packet_now(con_handle)){
2534                 hci_send_acl_packet_fragments(connection);
2535                 return;
2536             }
2537         } else {
2538             // connection gone -> discard further fragments
2539             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
2540             hci_stack->acl_fragmentation_total_size = 0;
2541             hci_stack->acl_fragmentation_pos = 0;
2542         }
2543     }
2544 
2545     if (!hci_can_send_command_packet_now()) return;
2546 
2547     // global/non-connection oriented commands
2548 
2549 #ifdef ENABLE_CLASSIC
2550     // decline incoming connections
2551     if (hci_stack->decline_reason){
2552         uint8_t reason = hci_stack->decline_reason;
2553         hci_stack->decline_reason = 0;
2554         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
2555         return;
2556     }
2557 
2558     // send scan enable
2559     if (hci_stack->state == HCI_STATE_WORKING && hci_stack->new_scan_enable_value != 0xff && hci_classic_supported()){
2560         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
2561         hci_stack->new_scan_enable_value = 0xff;
2562         return;
2563     }
2564 #endif
2565 
2566 #ifdef ENABLE_BLE
2567     if (hci_stack->state == HCI_STATE_WORKING){
2568 
2569 #ifdef ENABLE_LE_CENTRAL
2570         // handle le scan
2571         switch(hci_stack->le_scanning_state){
2572             case LE_START_SCAN:
2573                 hci_stack->le_scanning_state = LE_SCANNING;
2574                 hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
2575                 return;
2576 
2577             case LE_STOP_SCAN:
2578                 hci_stack->le_scanning_state = LE_SCAN_IDLE;
2579                 hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
2580                 return;
2581             default:
2582                 break;
2583         }
2584         if (hci_stack->le_scan_type != 0xff){
2585             // defaults: active scanning, accept all advertisement packets
2586             int scan_type = hci_stack->le_scan_type;
2587             hci_stack->le_scan_type = 0xff;
2588             hci_send_cmd(&hci_le_set_scan_parameters, scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window, hci_stack->adv_addr_type, 0);
2589             return;
2590         }
2591 #endif
2592 #ifdef ENABLE_LE_PERIPHERAL
2593         // le advertisement control
2594         if (hci_stack->le_advertisements_todo){
2595             log_info("hci_run: gap_le: adv todo: %x", hci_stack->le_advertisements_todo );
2596         }
2597         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_DISABLE){
2598             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_DISABLE;
2599             hci_send_cmd(&hci_le_set_advertise_enable, 0);
2600             return;
2601         }
2602         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
2603             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
2604             hci_send_cmd(&hci_le_set_advertising_parameters,
2605                  hci_stack->le_advertisements_interval_min,
2606                  hci_stack->le_advertisements_interval_max,
2607                  hci_stack->le_advertisements_type,
2608                  hci_stack->le_advertisements_own_address_type,
2609                  hci_stack->le_advertisements_direct_address_type,
2610                  hci_stack->le_advertisements_direct_address,
2611                  hci_stack->le_advertisements_channel_map,
2612                  hci_stack->le_advertisements_filter_policy);
2613             return;
2614         }
2615         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
2616             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
2617             hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len,
2618                 hci_stack->le_advertisements_data);
2619             return;
2620         }
2621         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
2622             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
2623             hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len,
2624                 hci_stack->le_scan_response_data);
2625             return;
2626         }
2627         // Random address needs to be set before enabling advertisements
2628         if ((hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_ENABLE)
2629         &&  (hci_stack->le_advertisements_own_address_type == 0 || hci_stack->le_advertisements_random_address_set)){
2630             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_ENABLE;
2631             hci_send_cmd(&hci_le_set_advertise_enable, 1);
2632             return;
2633         }
2634 #endif
2635 
2636 #ifdef ENABLE_LE_CENTRAL
2637         //
2638         // LE Whitelist Management
2639         //
2640 
2641         // check if whitelist needs modification
2642         btstack_linked_list_iterator_t lit;
2643         int modification_pending = 0;
2644         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
2645         while (btstack_linked_list_iterator_has_next(&lit)){
2646             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
2647             if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
2648                 modification_pending = 1;
2649                 break;
2650             }
2651         }
2652 
2653         if (modification_pending){
2654             // stop connnecting if modification pending
2655             if (hci_stack->le_connecting_state != LE_CONNECTING_IDLE){
2656                 hci_send_cmd(&hci_le_create_connection_cancel);
2657                 return;
2658             }
2659 
2660             // add/remove entries
2661             btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
2662             while (btstack_linked_list_iterator_has_next(&lit)){
2663                 whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
2664                 if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
2665                     entry->state = LE_WHITELIST_ON_CONTROLLER;
2666                     hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
2667                     return;
2668 
2669                 }
2670                 if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
2671                     bd_addr_t address;
2672                     bd_addr_type_t address_type = entry->address_type;
2673                     memcpy(address, entry->address, 6);
2674                     btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
2675                     btstack_memory_whitelist_entry_free(entry);
2676                     hci_send_cmd(&hci_le_remove_device_from_white_list, address_type, address);
2677                     return;
2678                 }
2679             }
2680         }
2681 
2682         // start connecting
2683         if ( hci_stack->le_connecting_state == LE_CONNECTING_IDLE &&
2684             !btstack_linked_list_empty(&hci_stack->le_whitelist)){
2685             bd_addr_t null_addr;
2686             memset(null_addr, 0, 6);
2687             hci_send_cmd(&hci_le_create_connection,
2688                  0x0060,    // scan interval: 60 ms
2689                  0x0030,    // scan interval: 30 ms
2690                  1,         // use whitelist
2691                  0,         // peer address type
2692                  null_addr,      // peer bd addr
2693                  hci_stack->adv_addr_type, // our addr type:
2694                  0x0008,    // conn interval min
2695                  0x0018,    // conn interval max
2696                  0,         // conn latency
2697                  0x0048,    // supervision timeout
2698                  0x0001,    // min ce length
2699                  0x0001     // max ce length
2700                  );
2701             return;
2702         }
2703 #endif
2704     }
2705 #endif
2706 
2707     // send pending HCI commands
2708     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
2709         hci_connection_t * connection = (hci_connection_t *) it;
2710 
2711         switch(connection->state){
2712             case SEND_CREATE_CONNECTION:
2713                 switch(connection->address_type){
2714 #ifdef ENABLE_CLASSIC
2715                     case BD_ADDR_TYPE_CLASSIC:
2716                         log_info("sending hci_create_connection");
2717                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, 1);
2718                         break;
2719 #endif
2720                     default:
2721 #ifdef ENABLE_BLE
2722 #ifdef ENABLE_LE_CENTRAL
2723                         log_info("sending hci_le_create_connection");
2724                         hci_send_cmd(&hci_le_create_connection,
2725                                      0x0060,    // scan interval: 60 ms
2726                                      0x0030,    // scan interval: 30 ms
2727                                      0,         // don't use whitelist
2728                                      connection->address_type, // peer address type
2729                                      connection->address,      // peer bd addr
2730                                      hci_stack->adv_addr_type, // our addr type:
2731                                      0x0008,    // conn interval min
2732                                      0x0018,    // conn interval max
2733                                      0,         // conn latency
2734                                      0x0048,    // supervision timeout
2735                                      0x0001,    // min ce length
2736                                      0x0001     // max ce length
2737                                      );
2738 
2739                         connection->state = SENT_CREATE_CONNECTION;
2740 #endif
2741 #endif
2742                         break;
2743                 }
2744                 return;
2745 
2746 #ifdef ENABLE_CLASSIC
2747             case RECEIVED_CONNECTION_REQUEST:
2748                 log_info("sending hci_accept_connection_request, remote eSCO %u", connection->remote_supported_feature_eSCO);
2749                 connection->state = ACCEPTED_CONNECTION_REQUEST;
2750                 connection->role  = HCI_ROLE_SLAVE;
2751                 if (connection->address_type == BD_ADDR_TYPE_CLASSIC){
2752                     hci_send_cmd(&hci_accept_connection_request, connection->address, 1);
2753                 }
2754                 return;
2755 #endif
2756 
2757 #ifdef ENABLE_BLE
2758 #ifdef ENABLE_LE_CENTRAL
2759             case SEND_CANCEL_CONNECTION:
2760                 connection->state = SENT_CANCEL_CONNECTION;
2761                 hci_send_cmd(&hci_le_create_connection_cancel);
2762                 return;
2763 #endif
2764 #endif
2765             case SEND_DISCONNECT:
2766                 connection->state = SENT_DISCONNECT;
2767                 hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13); // remote closed connection
2768                 return;
2769 
2770             default:
2771                 break;
2772         }
2773 
2774 #ifdef ENABLE_CLASSIC
2775         if (connection->authentication_flags & HANDLE_LINK_KEY_REQUEST){
2776             log_info("responding to link key request");
2777             connectionClearAuthenticationFlags(connection, HANDLE_LINK_KEY_REQUEST);
2778             link_key_t link_key;
2779             link_key_type_t link_key_type;
2780             if ( hci_stack->link_key_db
2781               && hci_stack->link_key_db->get_link_key(connection->address, link_key, &link_key_type)
2782               && gap_security_level_for_link_key_type(link_key_type) >= connection->requested_security_level){
2783                connection->link_key_type = link_key_type;
2784                hci_send_cmd(&hci_link_key_request_reply, connection->address, &link_key);
2785             } else {
2786                hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
2787             }
2788             return;
2789         }
2790 
2791         if (connection->authentication_flags & DENY_PIN_CODE_REQUEST){
2792             log_info("denying to pin request");
2793             connectionClearAuthenticationFlags(connection, DENY_PIN_CODE_REQUEST);
2794             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
2795             return;
2796         }
2797 
2798         if (connection->authentication_flags & SEND_IO_CAPABILITIES_REPLY){
2799             connectionClearAuthenticationFlags(connection, SEND_IO_CAPABILITIES_REPLY);
2800             log_info("IO Capability Request received, stack bondable %u, io cap %u", hci_stack->bondable, hci_stack->ssp_io_capability);
2801             if (hci_stack->bondable && (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN)){
2802                 // tweak authentication requirements
2803                 uint8_t authreq = hci_stack->ssp_authentication_requirement;
2804                 if (connection->bonding_flags & BONDING_DEDICATED){
2805                     authreq = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
2806                 }
2807                 if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
2808                     authreq |= 1;
2809                 }
2810                 hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, NULL, authreq);
2811             } else {
2812                 hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
2813             }
2814             return;
2815         }
2816 
2817         if (connection->authentication_flags & SEND_USER_CONFIRM_REPLY){
2818             connectionClearAuthenticationFlags(connection, SEND_USER_CONFIRM_REPLY);
2819             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
2820             return;
2821         }
2822 
2823         if (connection->authentication_flags & SEND_USER_PASSKEY_REPLY){
2824             connectionClearAuthenticationFlags(connection, SEND_USER_PASSKEY_REPLY);
2825             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
2826             return;
2827         }
2828 
2829         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES){
2830             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES;
2831             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
2832             return;
2833         }
2834 
2835         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
2836             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
2837             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
2838             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // authentication done
2839             return;
2840         }
2841 
2842         if (connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST){
2843             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
2844             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
2845             return;
2846         }
2847 
2848         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
2849             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
2850             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
2851             return;
2852         }
2853 #endif
2854 
2855         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
2856             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
2857             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x0005);  // authentication failure
2858             return;
2859         }
2860 
2861 #ifdef ENABLE_BLE
2862         if (connection->le_con_parameter_update_state == CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS){
2863             connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
2864 
2865             uint16_t connection_interval_min = connection->le_conn_interval_min;
2866             connection->le_conn_interval_min = 0;
2867             hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection_interval_min,
2868                 connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
2869                 0x0000, 0xffff);
2870         }
2871 #endif
2872     }
2873 
2874     hci_connection_t * connection;
2875     switch (hci_stack->state){
2876         case HCI_STATE_INITIALIZING:
2877             hci_initializing_run();
2878             break;
2879 
2880         case HCI_STATE_HALTING:
2881 
2882             log_info("HCI_STATE_HALTING");
2883 
2884             // free whitelist entries
2885 #ifdef ENABLE_BLE
2886 #ifdef ENABLE_LE_CENTRAL
2887             {
2888                 btstack_linked_list_iterator_t lit;
2889                 btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
2890                 while (btstack_linked_list_iterator_has_next(&lit)){
2891                     whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
2892                     btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
2893                     btstack_memory_whitelist_entry_free(entry);
2894                 }
2895             }
2896 #endif
2897 #endif
2898             // close all open connections
2899             connection =  (hci_connection_t *) hci_stack->connections;
2900             if (connection){
2901                 hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
2902                 if (!hci_can_send_command_packet_now()) return;
2903 
2904                 log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
2905 
2906                 // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
2907                 hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
2908 
2909                 // ... which would be ignored anyway as we shutdown (free) the connection now
2910                 hci_shutdown_connection(connection);
2911 
2912                 // finally, send the disconnect command
2913                 hci_send_cmd(&hci_disconnect, con_handle, 0x13);  // remote closed connection
2914                 return;
2915             }
2916             log_info("HCI_STATE_HALTING, calling off");
2917 
2918             // switch mode
2919             hci_power_control_off();
2920 
2921             log_info("HCI_STATE_HALTING, emitting state");
2922             hci_emit_state();
2923             log_info("HCI_STATE_HALTING, done");
2924             break;
2925 
2926         case HCI_STATE_FALLING_ASLEEP:
2927             switch(hci_stack->substate) {
2928                 case HCI_FALLING_ASLEEP_DISCONNECT:
2929                     log_info("HCI_STATE_FALLING_ASLEEP");
2930                     // close all open connections
2931                     connection =  (hci_connection_t *) hci_stack->connections;
2932 
2933 #ifdef HAVE_PLATFORM_IPHONE_OS
2934                     // don't close connections, if H4 supports power management
2935                     if (btstack_control_iphone_power_management_enabled()){
2936                         connection = NULL;
2937                     }
2938 #endif
2939                     if (connection){
2940 
2941                         // send disconnect
2942                         if (!hci_can_send_command_packet_now()) return;
2943 
2944                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
2945                         hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // remote closed connection
2946 
2947                         // send disconnected event right away - causes higher layer connections to get closed, too.
2948                         hci_shutdown_connection(connection);
2949                         return;
2950                     }
2951 
2952                     if (hci_classic_supported()){
2953                         // disable page and inquiry scan
2954                         if (!hci_can_send_command_packet_now()) return;
2955 
2956                         log_info("HCI_STATE_HALTING, disabling inq scans");
2957                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
2958 
2959                         // continue in next sub state
2960                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
2961                         break;
2962                     }
2963                     // no break - fall through for ble-only chips
2964 
2965                 case HCI_FALLING_ASLEEP_COMPLETE:
2966                     log_info("HCI_STATE_HALTING, calling sleep");
2967 #ifdef HAVE_PLATFORM_IPHONE_OS
2968                     // don't actually go to sleep, if H4 supports power management
2969                     if (btstack_control_iphone_power_management_enabled()){
2970                         // SLEEP MODE reached
2971                         hci_stack->state = HCI_STATE_SLEEPING;
2972                         hci_emit_state();
2973                         break;
2974                     }
2975 #endif
2976                     // switch mode
2977                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
2978                     hci_emit_state();
2979                     break;
2980 
2981                 default:
2982                     break;
2983             }
2984             break;
2985 
2986         default:
2987             break;
2988     }
2989 }
2990 
2991 int hci_send_cmd_packet(uint8_t *packet, int size){
2992     // house-keeping
2993 
2994     if (IS_COMMAND(packet, hci_write_loopback_mode)){
2995         hci_stack->loopback_mode = packet[3];
2996     }
2997 
2998 #ifdef ENABLE_CLASSIC
2999     bd_addr_t addr;
3000     hci_connection_t * conn;
3001 
3002     // create_connection?
3003     if (IS_COMMAND(packet, hci_create_connection)){
3004         reverse_bd_addr(&packet[3], addr);
3005         log_info("Create_connection to %s", bd_addr_to_str(addr));
3006 
3007         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
3008         if (!conn){
3009             conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
3010             if (!conn){
3011                 // notify client that alloc failed
3012                 hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
3013                 return 0; // don't sent packet to controller
3014             }
3015             conn->state = SEND_CREATE_CONNECTION;
3016         }
3017         log_info("conn state %u", conn->state);
3018         switch (conn->state){
3019             // if connection active exists
3020             case OPEN:
3021                 // and OPEN, emit connection complete command, don't send to controller
3022                 hci_emit_connection_complete(addr, conn->con_handle, 0);
3023                 return 0;
3024             case SEND_CREATE_CONNECTION:
3025                 // connection created by hci, e.g. dedicated bonding
3026                 break;
3027             default:
3028                 // otherwise, just ignore as it is already in the open process
3029                 return 0;
3030         }
3031         conn->state = SENT_CREATE_CONNECTION;
3032     }
3033 
3034     if (IS_COMMAND(packet, hci_link_key_request_reply)){
3035         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
3036     }
3037     if (IS_COMMAND(packet, hci_link_key_request_negative_reply)){
3038         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
3039     }
3040 
3041     if (IS_COMMAND(packet, hci_delete_stored_link_key)){
3042         if (hci_stack->link_key_db){
3043             reverse_bd_addr(&packet[3], addr);
3044             hci_stack->link_key_db->delete_link_key(addr);
3045         }
3046     }
3047 
3048     if (IS_COMMAND(packet, hci_pin_code_request_negative_reply)
3049     ||  IS_COMMAND(packet, hci_pin_code_request_reply)){
3050         reverse_bd_addr(&packet[3], addr);
3051         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
3052         if (conn){
3053             connectionClearAuthenticationFlags(conn, LEGACY_PAIRING_ACTIVE);
3054         }
3055     }
3056 
3057     if (IS_COMMAND(packet, hci_user_confirmation_request_negative_reply)
3058     ||  IS_COMMAND(packet, hci_user_confirmation_request_reply)
3059     ||  IS_COMMAND(packet, hci_user_passkey_request_negative_reply)
3060     ||  IS_COMMAND(packet, hci_user_passkey_request_reply)) {
3061         reverse_bd_addr(&packet[3], addr);
3062         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
3063         if (conn){
3064             connectionClearAuthenticationFlags(conn, SSP_PAIRING_ACTIVE);
3065         }
3066     }
3067 #endif
3068 
3069 #ifdef ENABLE_BLE
3070 #ifdef ENABLE_LE_PERIPHERAL
3071     if (IS_COMMAND(packet, hci_le_set_random_address)){
3072         hci_stack->le_advertisements_random_address_set = 1;
3073         reverse_bd_addr(&packet[3], hci_stack->adv_address);
3074     }
3075     if (IS_COMMAND(packet, hci_le_set_advertising_parameters)){
3076         hci_stack->adv_addr_type = packet[8];
3077     }
3078     if (IS_COMMAND(packet, hci_le_set_advertise_enable)){
3079         hci_stack->le_advertisements_active = packet[3];
3080     }
3081 #endif
3082 #ifdef ENABLE_LE_CENTRAL
3083     if (IS_COMMAND(packet, hci_le_create_connection)){
3084         // white list used?
3085         uint8_t initiator_filter_policy = packet[7];
3086         switch (initiator_filter_policy){
3087             case 0:
3088                 // whitelist not used
3089                 hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
3090                 break;
3091             case 1:
3092                 hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
3093                 break;
3094             default:
3095                 log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
3096                 break;
3097         }
3098     }
3099     if (IS_COMMAND(packet, hci_le_create_connection_cancel)){
3100         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
3101     }
3102 #endif
3103 #endif
3104 
3105     hci_stack->num_cmd_packets--;
3106 
3107     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
3108     int err = hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
3109 
3110     // release packet buffer for synchronous transport implementations
3111     if (hci_transport_synchronous() && (packet == hci_stack->hci_packet_buffer)){
3112         hci_stack->hci_packet_buffer_reserved = 0;
3113     }
3114 
3115     return err;
3116 }
3117 
3118 // disconnect because of security block
3119 void hci_disconnect_security_block(hci_con_handle_t con_handle){
3120     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3121     if (!connection) return;
3122     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
3123 }
3124 
3125 
3126 // Configure Secure Simple Pairing
3127 
3128 #ifdef ENABLE_CLASSIC
3129 
3130 // enable will enable SSP during init
3131 void gap_ssp_set_enable(int enable){
3132     hci_stack->ssp_enable = enable;
3133 }
3134 
3135 static int hci_local_ssp_activated(void){
3136     return gap_ssp_supported() && hci_stack->ssp_enable;
3137 }
3138 
3139 // if set, BTstack will respond to io capability request using authentication requirement
3140 void gap_ssp_set_io_capability(int io_capability){
3141     hci_stack->ssp_io_capability = io_capability;
3142 }
3143 void gap_ssp_set_authentication_requirement(int authentication_requirement){
3144     hci_stack->ssp_authentication_requirement = authentication_requirement;
3145 }
3146 
3147 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
3148 void gap_ssp_set_auto_accept(int auto_accept){
3149     hci_stack->ssp_auto_accept = auto_accept;
3150 }
3151 #endif
3152 
3153 // va_list part of hci_send_cmd
3154 int hci_send_cmd_va_arg(const hci_cmd_t *cmd, va_list argptr){
3155     if (!hci_can_send_command_packet_now()){
3156         log_error("hci_send_cmd called but cannot send packet now");
3157         return 0;
3158     }
3159 
3160     // for HCI INITIALIZATION
3161     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
3162     hci_stack->last_cmd_opcode = cmd->opcode;
3163 
3164     hci_reserve_packet_buffer();
3165     uint8_t * packet = hci_stack->hci_packet_buffer;
3166     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
3167     return hci_send_cmd_packet(packet, size);
3168 }
3169 
3170 /**
3171  * pre: numcmds >= 0 - it's allowed to send a command to the controller
3172  */
3173 int hci_send_cmd(const hci_cmd_t *cmd, ...){
3174     va_list argptr;
3175     va_start(argptr, cmd);
3176     int res = hci_send_cmd_va_arg(cmd, argptr);
3177     va_end(argptr);
3178     return res;
3179 }
3180 
3181 // Create various non-HCI events.
3182 // TODO: generalize, use table similar to hci_create_command
3183 
3184 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
3185     // dump packet
3186     if (dump) {
3187         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
3188     }
3189 
3190     // dispatch to all event handlers
3191     btstack_linked_list_iterator_t it;
3192     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
3193     while (btstack_linked_list_iterator_has_next(&it)){
3194         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
3195         entry->callback(HCI_EVENT_PACKET, 0, event, size);
3196     }
3197 }
3198 
3199 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
3200     if (!hci_stack->acl_packet_handler) return;
3201     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
3202 }
3203 
3204 #ifdef ENABLE_CLASSIC
3205 static void hci_notify_if_sco_can_send_now(void){
3206     // notify SCO sender if waiting
3207     if (!hci_stack->sco_waiting_for_can_send_now) return;
3208     if (hci_can_send_sco_packet_now()){
3209         hci_stack->sco_waiting_for_can_send_now = 0;
3210         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
3211         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
3212         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
3213     }
3214 }
3215 #endif
3216 
3217 void hci_emit_state(void){
3218     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
3219     uint8_t event[3];
3220     event[0] = BTSTACK_EVENT_STATE;
3221     event[1] = sizeof(event) - 2;
3222     event[2] = hci_stack->state;
3223     hci_emit_event(event, sizeof(event), 1);
3224 }
3225 
3226 #ifdef ENABLE_CLASSIC
3227 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
3228     uint8_t event[13];
3229     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
3230     event[1] = sizeof(event) - 2;
3231     event[2] = status;
3232     little_endian_store_16(event, 3, con_handle);
3233     reverse_bd_addr(address, &event[5]);
3234     event[11] = 1; // ACL connection
3235     event[12] = 0; // encryption disabled
3236     hci_emit_event(event, sizeof(event), 1);
3237 }
3238 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
3239     if (disable_l2cap_timeouts) return;
3240     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
3241     uint8_t event[4];
3242     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
3243     event[1] = sizeof(event) - 2;
3244     little_endian_store_16(event, 2, conn->con_handle);
3245     hci_emit_event(event, sizeof(event), 1);
3246 }
3247 #endif
3248 
3249 #ifdef ENABLE_BLE
3250 #ifdef ENABLE_LE_CENTRAL
3251 static void hci_emit_le_connection_complete(uint8_t address_type, bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
3252     uint8_t event[21];
3253     event[0] = HCI_EVENT_LE_META;
3254     event[1] = sizeof(event) - 2;
3255     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
3256     event[3] = status;
3257     little_endian_store_16(event, 4, con_handle);
3258     event[6] = 0; // TODO: role
3259     event[7] = address_type;
3260     reverse_bd_addr(address, &event[8]);
3261     little_endian_store_16(event, 14, 0); // interval
3262     little_endian_store_16(event, 16, 0); // latency
3263     little_endian_store_16(event, 18, 0); // supervision timeout
3264     event[20] = 0; // master clock accuracy
3265     hci_emit_event(event, sizeof(event), 1);
3266 }
3267 #endif
3268 #endif
3269 
3270 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
3271     uint8_t event[6];
3272     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
3273     event[1] = sizeof(event) - 2;
3274     event[2] = 0; // status = OK
3275     little_endian_store_16(event, 3, con_handle);
3276     event[5] = reason;
3277     hci_emit_event(event, sizeof(event), 1);
3278 }
3279 
3280 static void hci_emit_nr_connections_changed(void){
3281     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
3282     uint8_t event[3];
3283     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
3284     event[1] = sizeof(event) - 2;
3285     event[2] = nr_hci_connections();
3286     hci_emit_event(event, sizeof(event), 1);
3287 }
3288 
3289 static void hci_emit_hci_open_failed(void){
3290     log_info("BTSTACK_EVENT_POWERON_FAILED");
3291     uint8_t event[2];
3292     event[0] = BTSTACK_EVENT_POWERON_FAILED;
3293     event[1] = sizeof(event) - 2;
3294     hci_emit_event(event, sizeof(event), 1);
3295 }
3296 
3297 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
3298     log_info("hci_emit_dedicated_bonding_result %u ", status);
3299     uint8_t event[9];
3300     int pos = 0;
3301     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
3302     event[pos++] = sizeof(event) - 2;
3303     event[pos++] = status;
3304     reverse_bd_addr(address, &event[pos]);
3305     hci_emit_event(event, sizeof(event), 1);
3306 }
3307 
3308 
3309 #ifdef ENABLE_CLASSIC
3310 
3311 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
3312     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
3313     uint8_t event[5];
3314     int pos = 0;
3315     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
3316     event[pos++] = sizeof(event) - 2;
3317     little_endian_store_16(event, 2, con_handle);
3318     pos += 2;
3319     event[pos++] = level;
3320     hci_emit_event(event, sizeof(event), 1);
3321 }
3322 
3323 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
3324     if (!connection) return LEVEL_0;
3325     if ((connection->authentication_flags & CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
3326     return gap_security_level_for_link_key_type(connection->link_key_type);
3327 }
3328 
3329 static void hci_emit_discoverable_enabled(uint8_t enabled){
3330     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
3331     uint8_t event[3];
3332     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
3333     event[1] = sizeof(event) - 2;
3334     event[2] = enabled;
3335     hci_emit_event(event, sizeof(event), 1);
3336 }
3337 
3338 #ifdef ENABLE_CLASSIC
3339 // query if remote side supports eSCO
3340 int hci_remote_esco_supported(hci_con_handle_t con_handle){
3341     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3342     if (!connection) return 0;
3343     return connection->remote_supported_feature_eSCO;
3344 }
3345 
3346 // query if remote side supports SSP
3347 int hci_remote_ssp_supported(hci_con_handle_t con_handle){
3348     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3349     if (!connection) return 0;
3350     return (connection->bonding_flags & BONDING_REMOTE_SUPPORTS_SSP) ? 1 : 0;
3351 }
3352 
3353 int gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
3354     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
3355 }
3356 #endif
3357 
3358 // GAP API
3359 /**
3360  * @bbrief enable/disable bonding. default is enabled
3361  * @praram enabled
3362  */
3363 void gap_set_bondable_mode(int enable){
3364     hci_stack->bondable = enable ? 1 : 0;
3365 }
3366 /**
3367  * @brief Get bondable mode.
3368  * @return 1 if bondable
3369  */
3370 int gap_get_bondable_mode(void){
3371     return hci_stack->bondable;
3372 }
3373 
3374 /**
3375  * @brief map link keys to security levels
3376  */
3377 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
3378     switch (link_key_type){
3379         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
3380             return LEVEL_4;
3381         case COMBINATION_KEY:
3382         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
3383             return LEVEL_3;
3384         default:
3385             return LEVEL_2;
3386     }
3387 }
3388 
3389 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
3390     log_info("gap_mitm_protection_required_for_security_level %u", level);
3391     return level > LEVEL_2;
3392 }
3393 
3394 /**
3395  * @brief get current security level
3396  */
3397 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
3398     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3399     if (!connection) return LEVEL_0;
3400     return gap_security_level_for_connection(connection);
3401 }
3402 
3403 /**
3404  * @brief request connection to device to
3405  * @result GAP_AUTHENTICATION_RESULT
3406  */
3407 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
3408     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3409     if (!connection){
3410         hci_emit_security_level(con_handle, LEVEL_0);
3411         return;
3412     }
3413     gap_security_level_t current_level = gap_security_level(con_handle);
3414     log_info("gap_request_security_level %u, current level %u", requested_level, current_level);
3415     if (current_level >= requested_level){
3416         hci_emit_security_level(con_handle, current_level);
3417         return;
3418     }
3419 
3420     connection->requested_security_level = requested_level;
3421 
3422 #if 0
3423     // sending encryption request without a link key results in an error.
3424     // TODO: figure out how to use it properly
3425 
3426     // would enabling ecnryption suffice (>= LEVEL_2)?
3427     if (hci_stack->link_key_db){
3428         link_key_type_t link_key_type;
3429         link_key_t      link_key;
3430         if (hci_stack->link_key_db->get_link_key( &connection->address, &link_key, &link_key_type)){
3431             if (gap_security_level_for_link_key_type(link_key_type) >= requested_level){
3432                 connection->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
3433                 return;
3434             }
3435         }
3436     }
3437 #endif
3438 
3439     // try to authenticate connection
3440     connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
3441     hci_run();
3442 }
3443 
3444 /**
3445  * @brief start dedicated bonding with device. disconnect after bonding
3446  * @param device
3447  * @param request MITM protection
3448  * @result GAP_DEDICATED_BONDING_COMPLETE
3449  */
3450 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
3451 
3452     // create connection state machine
3453     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_CLASSIC);
3454 
3455     if (!connection){
3456         return BTSTACK_MEMORY_ALLOC_FAILED;
3457     }
3458 
3459     // delete linkn key
3460     gap_drop_link_key_for_bd_addr(device);
3461 
3462     // configure LEVEL_2/3, dedicated bonding
3463     connection->state = SEND_CREATE_CONNECTION;
3464     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
3465     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
3466     connection->bonding_flags = BONDING_DEDICATED;
3467 
3468     // wait for GAP Security Result and send GAP Dedicated Bonding complete
3469 
3470     // handle: connnection failure (connection complete != ok)
3471     // handle: authentication failure
3472     // handle: disconnect on done
3473 
3474     hci_run();
3475 
3476     return 0;
3477 }
3478 #endif
3479 
3480 void gap_set_local_name(const char * local_name){
3481     hci_stack->local_name = local_name;
3482 }
3483 
3484 
3485 #ifdef ENABLE_BLE
3486 
3487 #ifdef ENABLE_LE_CENTRAL
3488 void gap_start_scan(void){
3489     if (hci_stack->le_scanning_state == LE_SCANNING) return;
3490     hci_stack->le_scanning_state = LE_START_SCAN;
3491     hci_run();
3492 }
3493 
3494 void gap_stop_scan(void){
3495     if ( hci_stack->le_scanning_state == LE_SCAN_IDLE) return;
3496     hci_stack->le_scanning_state = LE_STOP_SCAN;
3497     hci_run();
3498 }
3499 
3500 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
3501     hci_stack->le_scan_type     = scan_type;
3502     hci_stack->le_scan_interval = scan_interval;
3503     hci_stack->le_scan_window   = scan_window;
3504     hci_run();
3505 }
3506 
3507 uint8_t gap_connect(bd_addr_t addr, bd_addr_type_t addr_type){
3508     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
3509     if (!conn){
3510         log_info("gap_connect: no connection exists yet, creating context");
3511         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
3512         if (!conn){
3513             // notify client that alloc failed
3514             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
3515             log_info("gap_connect: failed to alloc hci_connection_t");
3516             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
3517         }
3518         conn->state = SEND_CREATE_CONNECTION;
3519         log_info("gap_connect: send create connection next");
3520         hci_run();
3521         return 0;
3522     }
3523 
3524     if (!hci_is_le_connection(conn) ||
3525         conn->state == SEND_CREATE_CONNECTION ||
3526         conn->state == SENT_CREATE_CONNECTION) {
3527         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
3528         log_error("gap_connect: classic connection or connect is already being created");
3529         return GATT_CLIENT_IN_WRONG_STATE;
3530     }
3531 
3532     log_info("gap_connect: context exists with state %u", conn->state);
3533     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, 0);
3534     hci_run();
3535     return 0;
3536 }
3537 
3538 // @assumption: only a single outgoing LE Connection exists
3539 static hci_connection_t * gap_get_outgoing_connection(void){
3540     btstack_linked_item_t *it;
3541     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
3542         hci_connection_t * conn = (hci_connection_t *) it;
3543         if (!hci_is_le_connection(conn)) continue;
3544         switch (conn->state){
3545             case SEND_CREATE_CONNECTION:
3546             case SENT_CREATE_CONNECTION:
3547                 return conn;
3548             default:
3549                 break;
3550         };
3551     }
3552     return NULL;
3553 }
3554 
3555 uint8_t gap_connect_cancel(void){
3556     hci_connection_t * conn = gap_get_outgoing_connection();
3557     if (!conn) return 0;
3558     switch (conn->state){
3559         case SEND_CREATE_CONNECTION:
3560             // skip sending create connection and emit event instead
3561             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
3562             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
3563             btstack_memory_hci_connection_free( conn );
3564             break;
3565         case SENT_CREATE_CONNECTION:
3566             // request to send cancel connection
3567             conn->state = SEND_CANCEL_CONNECTION;
3568             hci_run();
3569             break;
3570         default:
3571             break;
3572     }
3573     return 0;
3574 }
3575 #endif
3576 
3577 /**
3578  * @brief Updates the connection parameters for a given LE connection
3579  * @param handle
3580  * @param conn_interval_min (unit: 1.25ms)
3581  * @param conn_interval_max (unit: 1.25ms)
3582  * @param conn_latency
3583  * @param supervision_timeout (unit: 10ms)
3584  * @returns 0 if ok
3585  */
3586 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
3587     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
3588     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3589     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3590     connection->le_conn_interval_min = conn_interval_min;
3591     connection->le_conn_interval_max = conn_interval_max;
3592     connection->le_conn_latency = conn_latency;
3593     connection->le_supervision_timeout = supervision_timeout;
3594     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
3595     hci_run();
3596     return 0;
3597 }
3598 
3599 /**
3600  * @brief Request an update of the connection parameter for a given LE connection
3601  * @param handle
3602  * @param conn_interval_min (unit: 1.25ms)
3603  * @param conn_interval_max (unit: 1.25ms)
3604  * @param conn_latency
3605  * @param supervision_timeout (unit: 10ms)
3606  * @returns 0 if ok
3607  */
3608 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
3609     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
3610     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3611     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3612     connection->le_conn_interval_min = conn_interval_min;
3613     connection->le_conn_interval_max = conn_interval_max;
3614     connection->le_conn_latency = conn_latency;
3615     connection->le_supervision_timeout = supervision_timeout;
3616     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
3617     hci_run();
3618     return 0;
3619 }
3620 
3621 #ifdef ENABLE_LE_PERIPHERAL
3622 
3623 static void gap_advertisments_changed(void){
3624     // disable advertisements before updating adv, scan data, or adv params
3625     if (hci_stack->le_advertisements_active){
3626         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE | LE_ADVERTISEMENT_TASKS_ENABLE;
3627     }
3628     hci_run();
3629 }
3630 
3631 /**
3632  * @brief Set Advertisement Data
3633  * @param advertising_data_length
3634  * @param advertising_data (max 31 octets)
3635  * @note data is not copied, pointer has to stay valid
3636  */
3637 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
3638     hci_stack->le_advertisements_data_len = advertising_data_length;
3639     hci_stack->le_advertisements_data = advertising_data;
3640     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3641     gap_advertisments_changed();
3642 }
3643 
3644 /**
3645  * @brief Set Scan Response Data
3646  * @param advertising_data_length
3647  * @param advertising_data (max 31 octets)
3648  * @note data is not copied, pointer has to stay valid
3649  */
3650 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
3651     hci_stack->le_scan_response_data_len = scan_response_data_length;
3652     hci_stack->le_scan_response_data = scan_response_data;
3653     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
3654     gap_advertisments_changed();
3655 }
3656 
3657 /**
3658  * @brief Set Advertisement Parameters
3659  * @param adv_int_min
3660  * @param adv_int_max
3661  * @param adv_type
3662  * @param own_address_type
3663  * @param direct_address_type
3664  * @param direct_address
3665  * @param channel_map
3666  * @param filter_policy
3667  *
3668  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
3669  */
3670  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
3671     uint8_t own_address_type, uint8_t direct_address_typ, bd_addr_t direct_address,
3672     uint8_t channel_map, uint8_t filter_policy) {
3673 
3674     hci_stack->le_advertisements_interval_min = adv_int_min;
3675     hci_stack->le_advertisements_interval_max = adv_int_max;
3676     hci_stack->le_advertisements_type = adv_type;
3677     hci_stack->le_advertisements_own_address_type = own_address_type;
3678     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
3679     hci_stack->le_advertisements_channel_map = channel_map;
3680     hci_stack->le_advertisements_filter_policy = filter_policy;
3681     memcpy(hci_stack->le_advertisements_direct_address, direct_address, 6);
3682 
3683     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3684     gap_advertisments_changed();
3685  }
3686 
3687 void hci_le_advertisements_set_own_address_type(uint8_t own_address_type){
3688     hci_stack->le_advertisements_own_address_type = own_address_type;
3689     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3690     gap_advertisments_changed();
3691 }
3692 
3693 /**
3694  * @brief Enable/Disable Advertisements
3695  * @param enabled
3696  */
3697 void gap_advertisements_enable(int enabled){
3698     hci_stack->le_advertisements_enabled = enabled;
3699     if (enabled && !hci_stack->le_advertisements_active){
3700         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
3701     }
3702     if (!enabled && hci_stack->le_advertisements_active){
3703         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE;
3704     }
3705     hci_run();
3706 }
3707 
3708 #endif
3709 #endif
3710 
3711 uint8_t gap_disconnect(hci_con_handle_t handle){
3712     hci_connection_t * conn = hci_connection_for_handle(handle);
3713     if (!conn){
3714         hci_emit_disconnection_complete(handle, 0);
3715         return 0;
3716     }
3717     conn->state = SEND_DISCONNECT;
3718     hci_run();
3719     return 0;
3720 }
3721 
3722 /**
3723  * @brief Get connection type
3724  * @param con_handle
3725  * @result connection_type
3726  */
3727 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
3728     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
3729     if (!conn) return GAP_CONNECTION_INVALID;
3730     switch (conn->address_type){
3731         case BD_ADDR_TYPE_LE_PUBLIC:
3732         case BD_ADDR_TYPE_LE_RANDOM:
3733             return GAP_CONNECTION_LE;
3734         case BD_ADDR_TYPE_SCO:
3735             return GAP_CONNECTION_SCO;
3736         case BD_ADDR_TYPE_CLASSIC:
3737             return GAP_CONNECTION_ACL;
3738         default:
3739             return GAP_CONNECTION_INVALID;
3740     }
3741 }
3742 
3743 #ifdef ENABLE_BLE
3744 
3745 #ifdef ENABLE_LE_CENTRAL
3746 /**
3747  * @brief Auto Connection Establishment - Start Connecting to device
3748  * @param address_typ
3749  * @param address
3750  * @returns 0 if ok
3751  */
3752 int gap_auto_connection_start(bd_addr_type_t address_type, bd_addr_t address){
3753     // check capacity
3754     int num_entries = btstack_linked_list_count(&hci_stack->le_whitelist);
3755     if (num_entries >= hci_stack->le_whitelist_capacity) return ERROR_CODE_MEMORY_CAPACITY_EXCEEDED;
3756     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
3757     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
3758     entry->address_type = address_type;
3759     memcpy(entry->address, address, 6);
3760     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
3761     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
3762     hci_run();
3763     return 0;
3764 }
3765 
3766 static void hci_remove_from_whitelist(bd_addr_type_t address_type, bd_addr_t address){
3767     btstack_linked_list_iterator_t it;
3768     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
3769     while (btstack_linked_list_iterator_has_next(&it)){
3770         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
3771         if (entry->address_type != address_type) continue;
3772         if (memcmp(entry->address, address, 6) != 0) continue;
3773         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
3774             // remove from controller if already present
3775             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
3776             continue;
3777         }
3778         // direclty remove entry from whitelist
3779         btstack_linked_list_iterator_remove(&it);
3780         btstack_memory_whitelist_entry_free(entry);
3781     }
3782 }
3783 
3784 /**
3785  * @brief Auto Connection Establishment - Stop Connecting to device
3786  * @param address_typ
3787  * @param address
3788  * @returns 0 if ok
3789  */
3790 int gap_auto_connection_stop(bd_addr_type_t address_type, bd_addr_t address){
3791     hci_remove_from_whitelist(address_type, address);
3792     hci_run();
3793     return 0;
3794 }
3795 
3796 /**
3797  * @brief Auto Connection Establishment - Stop everything
3798  * @note  Convenience function to stop all active auto connection attempts
3799  */
3800 void gap_auto_connection_stop_all(void){
3801     btstack_linked_list_iterator_t it;
3802     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
3803     while (btstack_linked_list_iterator_has_next(&it)){
3804         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
3805         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
3806             // remove from controller if already present
3807             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
3808             continue;
3809         }
3810         // directly remove entry from whitelist
3811         btstack_linked_list_iterator_remove(&it);
3812         btstack_memory_whitelist_entry_free(entry);
3813     }
3814     hci_run();
3815 }
3816 #endif
3817 #endif
3818 
3819 #ifdef ENABLE_CLASSIC
3820 /**
3821  * @brief Set Extended Inquiry Response data
3822  * @param eir_data size 240 bytes, is not copied make sure memory is accessible during stack startup
3823  * @note has to be done before stack starts up
3824  */
3825 void gap_set_extended_inquiry_response(const uint8_t * data){
3826     hci_stack->eir_data = data;
3827 }
3828 
3829 /**
3830  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
3831  * @param inquriy_mode see bluetooth_defines.h
3832  */
3833 void hci_set_inquiry_mode(inquiry_mode_t mode){
3834     hci_stack->inquiry_mode = mode;
3835 }
3836 
3837 /**
3838  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
3839  */
3840 void hci_set_sco_voice_setting(uint16_t voice_setting){
3841     hci_stack->sco_voice_setting = voice_setting;
3842 }
3843 
3844 /**
3845  * @brief Get SCO Voice Setting
3846  * @return current voice setting
3847  */
3848 uint16_t hci_get_sco_voice_setting(void){
3849     return hci_stack->sco_voice_setting;
3850 }
3851 
3852 /** @brief Get SCO packet length for current SCO Voice setting
3853  *  @note  Using SCO packets of the exact length is required for USB transfer
3854  *  @return Length of SCO packets in bytes (not audio frames)
3855  */
3856 int hci_get_sco_packet_length(void){
3857     // see Core Spec for H2 USB Transfer.
3858     if (hci_stack->sco_voice_setting & 0x0020) return 51;
3859     return 27;
3860 }
3861 #endif
3862 
3863 /**
3864  * @brief Set callback for Bluetooth Hardware Error
3865  */
3866 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
3867     hci_stack->hardware_error_callback = fn;
3868 }
3869 
3870 void hci_disconnect_all(void){
3871     btstack_linked_list_iterator_t it;
3872     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
3873     while (btstack_linked_list_iterator_has_next(&it)){
3874         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
3875         if (con->state == SENT_DISCONNECT) continue;
3876         con->state = SEND_DISCONNECT;
3877     }
3878     hci_run();
3879 }
3880 
3881 uint16_t hci_get_manufacturer(void){
3882     return hci_stack->manufacturer;
3883 }
3884