xref: /btstack/src/hci.c (revision e691bb38f1811f4008ddf4b0f77f32b9dc785a39)
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 #ifdef ENABLE_BLE
859 
860 /**
861  * @brief Get addr type and address used for LE in Advertisements, Scan Responses,
862  */
863 void gap_le_get_own_address(uint8_t * addr_type, bd_addr_t addr){
864     *addr_type = hci_stack->le_own_addr_type;
865     if (hci_stack->le_own_addr_type){
866         memcpy(addr, hci_stack->le_random_address, 6);
867     } else {
868         memcpy(addr, hci_stack->local_bd_addr, 6);
869     }
870 }
871 
872 #ifdef ENABLE_LE_CENTRAL
873 void le_handle_advertisement_report(uint8_t *packet, int size){
874 
875     UNUSED(size);
876 
877     int offset = 3;
878     int num_reports = packet[offset];
879     offset += 1;
880 
881     int i;
882     // log_info("HCI: handle adv report with num reports: %d", num_reports);
883     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
884     for (i=0; i<num_reports;i++){
885         uint8_t data_length = packet[offset + 8];
886         uint8_t event_size = 10 + data_length;
887         int pos = 0;
888         event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
889         event[pos++] = event_size;
890         memcpy(&event[pos], &packet[offset], 1+1+6); // event type + address type + address
891         offset += 8;
892         pos += 8;
893         event[pos++] = packet[offset + 1 + data_length]; // rssi
894         event[pos++] = packet[offset++]; //data_length;
895         memcpy(&event[pos], &packet[offset], data_length);
896         pos += data_length;
897         offset += data_length + 1; // rssi
898         hci_emit_event(event, pos, 1);
899     }
900 }
901 #endif
902 #endif
903 
904 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
905 
906 static uint32_t hci_transport_uart_get_main_baud_rate(void){
907     if (!hci_stack->config) return 0;
908     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
909     // Limit baud rate for Broadcom chipsets to 3 mbps
910     if (hci_stack->manufacturer == COMPANY_ID_BROADCOM_CORPORATION && baud_rate > 3000000){
911         baud_rate = 3000000;
912     }
913     return baud_rate;
914 }
915 
916 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
917     UNUSED(ds);
918 
919     switch (hci_stack->substate){
920         case HCI_INIT_W4_SEND_RESET:
921             log_info("Resend HCI Reset");
922             hci_stack->substate = HCI_INIT_SEND_RESET;
923             hci_stack->num_cmd_packets = 1;
924             hci_run();
925             break;
926         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
927             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
928             if (hci_stack->hci_transport->reset_link){
929                 hci_stack->hci_transport->reset_link();
930             }
931             // no break - explicit fallthrough to HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT
932         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
933             log_info("Resend HCI Reset - CSR Warm Boot");
934             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
935             hci_stack->num_cmd_packets = 1;
936             hci_run();
937             break;
938         case HCI_INIT_W4_SEND_BAUD_CHANGE:
939             if (hci_stack->hci_transport->set_baudrate){
940                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
941                 log_info("Local baud rate change to %"PRIu32"(timeout handler)", baud_rate);
942                 hci_stack->hci_transport->set_baudrate(baud_rate);
943             }
944             // For CSR, HCI Reset is sent on new baud rate
945             if (hci_stack->manufacturer == COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
946                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
947                 hci_run();
948             }
949             break;
950         default:
951             break;
952     }
953 }
954 #endif
955 
956 static void hci_initializing_next_state(void){
957     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
958 }
959 
960 // assumption: hci_can_send_command_packet_now() == true
961 static void hci_initializing_run(void){
962     log_debug("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
963     switch (hci_stack->substate){
964         case HCI_INIT_SEND_RESET:
965             hci_state_reset();
966 
967 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
968             // prepare reset if command complete not received in 100ms
969             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
970             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
971             btstack_run_loop_add_timer(&hci_stack->timeout);
972 #endif
973             // send command
974             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
975             hci_send_cmd(&hci_reset);
976             break;
977         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
978             hci_send_cmd(&hci_read_local_version_information);
979             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
980             break;
981         case HCI_INIT_SEND_READ_LOCAL_NAME:
982             hci_send_cmd(&hci_read_local_name);
983             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
984             break;
985 
986 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
987         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
988             hci_state_reset();
989             // prepare reset if command complete not received in 100ms
990             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
991             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
992             btstack_run_loop_add_timer(&hci_stack->timeout);
993             // send command
994             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
995             hci_send_cmd(&hci_reset);
996             break;
997         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
998             hci_state_reset();
999             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1000             hci_send_cmd(&hci_reset);
1001             break;
1002         case HCI_INIT_SEND_BAUD_CHANGE: {
1003             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1004             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1005             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1006             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1007             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1008             // STLC25000D: baudrate change happens within 0.5 s after command was send,
1009             // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1010             if (hci_stack->manufacturer == COMPANY_ID_ST_MICROELECTRONICS){
1011                 btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1012                 btstack_run_loop_add_timer(&hci_stack->timeout);
1013             }
1014             break;
1015         }
1016         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1017             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1018             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1019             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1020             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1021             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1022             break;
1023         }
1024         case HCI_INIT_CUSTOM_INIT:
1025             // Custom initialization
1026             if (hci_stack->chipset && hci_stack->chipset->next_command){
1027                 int valid_cmd = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1028                 if (valid_cmd){
1029                     int size = 3 + hci_stack->hci_packet_buffer[2];
1030                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1031                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1032                     switch (valid_cmd) {
1033                         case 1:
1034                         default:
1035                             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1036                             break;
1037                         case 2: // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1038                             log_info("CSR Warm Boot");
1039                             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1040                             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1041                             btstack_run_loop_add_timer(&hci_stack->timeout);
1042                             if (hci_stack->manufacturer == COMPANY_ID_CAMBRIDGE_SILICON_RADIO
1043                                 && hci_stack->config
1044                                 && hci_stack->chipset
1045                                 // && hci_stack->chipset->set_baudrate_command -- there's no such command
1046                                 && hci_stack->hci_transport->set_baudrate
1047                                 && hci_transport_uart_get_main_baud_rate()){
1048                                 hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1049                             } else {
1050                                hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1051                             }
1052                             break;
1053                     }
1054                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1055                     break;
1056                 }
1057                 log_info("Init script done");
1058 
1059                 // Init script download causes baud rate to reset on Broadcom chipsets, restore UART baud rate if needed
1060                 if (hci_stack->manufacturer == COMPANY_ID_BROADCOM_CORPORATION){
1061                     int need_baud_change = hci_stack->config
1062                         && hci_stack->chipset
1063                         && hci_stack->chipset->set_baudrate_command
1064                         && hci_stack->hci_transport->set_baudrate
1065                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1066                     if (need_baud_change) {
1067                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1068                         log_info("Local baud rate change to %"PRIu32" after init script (bcm)", baud_rate);
1069                         hci_stack->hci_transport->set_baudrate(baud_rate);
1070                     }
1071                 }
1072             }
1073             // otherwise continue
1074             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1075             hci_send_cmd(&hci_read_local_supported_commands);
1076             break;
1077         case HCI_INIT_SET_BD_ADDR:
1078             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1079             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1080             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1081             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1082             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1083             break;
1084 #endif
1085 
1086         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1087             log_info("Resend hci_read_local_supported_commands after CSR Warm Boot double reset");
1088             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1089             hci_send_cmd(&hci_read_local_supported_commands);
1090             break;
1091         case HCI_INIT_READ_BD_ADDR:
1092             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1093             hci_send_cmd(&hci_read_bd_addr);
1094             break;
1095         case HCI_INIT_READ_BUFFER_SIZE:
1096             hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1097             hci_send_cmd(&hci_read_buffer_size);
1098             break;
1099         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1100             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1101             hci_send_cmd(&hci_read_local_supported_features);
1102             break;
1103         case HCI_INIT_SET_EVENT_MASK:
1104             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1105             if (hci_le_supported()){
1106                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x3FFFFFFF);
1107             } else {
1108                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1109                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x1FFFFFFF);
1110             }
1111             break;
1112 #ifdef ENABLE_CLASSIC
1113         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1114             hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1115             hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1116             break;
1117         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1118             hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1119             hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1120             break;
1121         case HCI_INIT_WRITE_CLASS_OF_DEVICE:
1122             hci_stack->substate = HCI_INIT_W4_WRITE_CLASS_OF_DEVICE;
1123             hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1124             break;
1125         case HCI_INIT_WRITE_LOCAL_NAME:
1126             hci_stack->substate = HCI_INIT_W4_WRITE_LOCAL_NAME;
1127             if (hci_stack->local_name){
1128                 hci_send_cmd(&hci_write_local_name, hci_stack->local_name);
1129             } else {
1130                 char local_name[8+17+1];
1131                 // BTstack 11:22:33:44:55:66
1132                 memcpy(local_name, "BTstack ", 8);
1133                 memcpy(&local_name[8], bd_addr_to_str(hci_stack->local_bd_addr), 17);   // strlen(bd_addr_to_str(...)) = 17
1134                 local_name[8+17] = '\0';
1135                 log_info("---> Name %s", local_name);
1136                 hci_send_cmd(&hci_write_local_name, local_name);
1137             }
1138             break;
1139         case HCI_INIT_WRITE_EIR_DATA:
1140             hci_stack->substate = HCI_INIT_W4_WRITE_EIR_DATA;
1141             hci_send_cmd(&hci_write_extended_inquiry_response, 0, hci_stack->eir_data);
1142             break;
1143         case HCI_INIT_WRITE_INQUIRY_MODE:
1144             hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1145             hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1146             break;
1147         case HCI_INIT_WRITE_SCAN_ENABLE:
1148             hci_send_cmd(&hci_write_scan_enable, (hci_stack->connectable << 1) | hci_stack->discoverable); // page scan
1149             hci_stack->substate = HCI_INIT_W4_WRITE_SCAN_ENABLE;
1150             break;
1151         // only sent if ENABLE_SCO_OVER_HCI is defined
1152         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1153             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1154             hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1155             break;
1156         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1157             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1158             hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1159             break;
1160 #endif
1161 #ifdef ENABLE_BLE
1162         // LE INIT
1163         case HCI_INIT_LE_READ_BUFFER_SIZE:
1164             hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1165             hci_send_cmd(&hci_le_read_buffer_size);
1166             break;
1167         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1168             // LE Supported Host = 1, Simultaneous Host = 0
1169             hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1170             hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1171             break;
1172 #ifdef ENABLE_LE_CENTRAL
1173         case HCI_INIT_READ_WHITE_LIST_SIZE:
1174             hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1175             hci_send_cmd(&hci_le_read_white_list_size);
1176             break;
1177         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1178             // LE Scan Parameters: active scanning, 300 ms interval, 30 ms window, own address type, accept all advs
1179             hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1180             hci_send_cmd(&hci_le_set_scan_parameters, 1, 0x1e0, 0x30, hci_stack->le_own_addr_type, 0);
1181             break;
1182 #endif
1183 #endif
1184         default:
1185             return;
1186     }
1187 }
1188 
1189 static void hci_init_done(void){
1190     // done. tell the app
1191     log_info("hci_init_done -> HCI_STATE_WORKING");
1192     hci_stack->state = HCI_STATE_WORKING;
1193     hci_emit_state();
1194     hci_run();
1195 }
1196 
1197 static void hci_initializing_event_handler(uint8_t * packet, uint16_t size){
1198     UNUSED(size);
1199 
1200     uint8_t command_completed = 0;
1201 
1202     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1203         uint16_t opcode = little_endian_read_16(packet,3);
1204         if (opcode == hci_stack->last_cmd_opcode){
1205             command_completed = 1;
1206             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1207         } else {
1208             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1209         }
1210     }
1211 
1212     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1213         uint8_t  status = packet[2];
1214         uint16_t opcode = little_endian_read_16(packet,4);
1215         if (opcode == hci_stack->last_cmd_opcode){
1216             if (status){
1217                 command_completed = 1;
1218                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1219             } else {
1220                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1221             }
1222         } else {
1223             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1224         }
1225     }
1226 
1227 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1228 
1229     // Vendor == CSR
1230     if (hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT && hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC){
1231         // TODO: track actual command
1232         command_completed = 1;
1233     }
1234 
1235     // Vendor == Toshiba
1236     if (hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE && hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC){
1237         // TODO: track actual command
1238         command_completed = 1;
1239     }
1240 
1241     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1242     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1243     //
1244     // HCI Reset
1245     // Timeout 100 ms
1246     // HCI Reset
1247     // Command Complete Reset
1248     // HCI Read Local Version Information
1249     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1250     // hang...
1251     //
1252     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1253     if (!command_completed
1254             && hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE
1255             && hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION){
1256 
1257         uint16_t opcode = little_endian_read_16(packet,3);
1258         if (opcode == hci_reset.opcode){
1259             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1260             return;
1261         }
1262     }
1263 
1264     // CSR & H5
1265     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1266     if (!command_completed
1267             && hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE
1268             && hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS){
1269 
1270         uint16_t opcode = little_endian_read_16(packet,3);
1271         if (opcode == hci_reset.opcode){
1272             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1273             return;
1274         }
1275     }
1276 
1277     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1278     // fix: Correct substate and behave as command below
1279     if (command_completed){
1280         switch (hci_stack->substate){
1281             case HCI_INIT_SEND_RESET:
1282                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1283                 break;
1284             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1285                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1286                 break;
1287             default:
1288                 break;
1289         }
1290     }
1291 
1292 #endif
1293 
1294     if (!command_completed) return;
1295 
1296     int need_baud_change = 0;
1297     int need_addr_change = 0;
1298 
1299 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1300     need_baud_change = hci_stack->config
1301                         && hci_stack->chipset
1302                         && hci_stack->chipset->set_baudrate_command
1303                         && hci_stack->hci_transport->set_baudrate
1304                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1305 
1306     need_addr_change = hci_stack->custom_bd_addr_set
1307                         && hci_stack->chipset
1308                         && hci_stack->chipset->set_bd_addr_command;
1309 #endif
1310 
1311     switch(hci_stack->substate){
1312 
1313 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1314         case HCI_INIT_SEND_RESET:
1315             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1316             // fix: just correct substate and behave as command below
1317             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1318             btstack_run_loop_remove_timer(&hci_stack->timeout);
1319             break;
1320         case HCI_INIT_W4_SEND_RESET:
1321             btstack_run_loop_remove_timer(&hci_stack->timeout);
1322             break;
1323         case HCI_INIT_W4_SEND_READ_LOCAL_NAME:
1324             log_info("Received local name, need baud change %d", need_baud_change);
1325             if (need_baud_change){
1326                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE;
1327                 return;
1328             }
1329             // skip baud change
1330             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1331             return;
1332         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1333             // for STLC2500D, baud rate change already happened.
1334             // for others, baud rate gets changed now
1335             if ((hci_stack->manufacturer != COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1336                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1337                 log_info("Local baud rate change to %"PRIu32"(w4_send_baud_change)", baud_rate);
1338                 hci_stack->hci_transport->set_baudrate(baud_rate);
1339             }
1340             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1341             return;
1342         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1343             btstack_run_loop_remove_timer(&hci_stack->timeout);
1344             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1345             return;
1346         case HCI_INIT_W4_CUSTOM_INIT:
1347             // repeat custom init
1348             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1349             return;
1350 #else
1351         case HCI_INIT_W4_SEND_RESET:
1352             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1353             return ;
1354 #endif
1355 
1356         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1357             if (need_baud_change && hci_stack->manufacturer == COMPANY_ID_BROADCOM_CORPORATION){
1358                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1359                 return;
1360             }
1361             if (need_addr_change){
1362                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1363                 return;
1364             }
1365             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1366             return;
1367 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1368         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1369             if (need_baud_change){
1370                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1371                 log_info("Local baud rate change to %"PRIu32"(w4_send_baud_change_bcm))", baud_rate);
1372                 hci_stack->hci_transport->set_baudrate(baud_rate);
1373             }
1374             if (need_addr_change){
1375                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1376                 return;
1377             }
1378             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1379             return;
1380         case HCI_INIT_W4_SET_BD_ADDR:
1381             // for STLC2500D, bd addr change only gets active after sending reset command
1382             if (hci_stack->manufacturer == COMPANY_ID_ST_MICROELECTRONICS){
1383                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1384                 return;
1385             }
1386             // skipping st warm boot
1387             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1388             return;
1389         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
1390             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1391             return;
1392 #endif
1393         case HCI_INIT_W4_READ_BD_ADDR:
1394             // only read buffer size if supported
1395             if (hci_stack->local_supported_commands[0] & 0x01) {
1396                 hci_stack->substate = HCI_INIT_READ_BUFFER_SIZE;
1397                 return;
1398             }
1399             // skipping read buffer size
1400             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES;
1401             return;
1402         case HCI_INIT_W4_SET_EVENT_MASK:
1403             // skip Classic init commands for LE only chipsets
1404             if (!hci_classic_supported()){
1405                 if (hci_le_supported()){
1406                     hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE; // skip all classic command
1407                     return;
1408                 } else {
1409                     log_error("Neither BR/EDR nor LE supported");
1410                     hci_init_done();
1411                     return;
1412                 }
1413             }
1414             if (!gap_ssp_supported()){
1415                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1416                 return;
1417             }
1418             break;
1419         case HCI_INIT_W4_LE_READ_BUFFER_SIZE:
1420             // skip write le host if not supported (e.g. on LE only EM9301)
1421             if (hci_stack->local_supported_commands[0] & 0x02) break;
1422             hci_stack->substate = HCI_INIT_LE_SET_SCAN_PARAMETERS;
1423             return;
1424         case HCI_INIT_W4_WRITE_LOCAL_NAME:
1425             // skip write eir data if no eir data set
1426             if (hci_stack->eir_data) break;
1427             hci_stack->substate = HCI_INIT_WRITE_INQUIRY_MODE;
1428             return;
1429 
1430 #ifdef ENABLE_SCO_OVER_HCI
1431         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1432             // skip write synchronous flow control if not supported
1433             if (hci_stack->local_supported_commands[0] & 0x04) break;
1434             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1435             // explicit fall through to reduce repetitions
1436 
1437         case HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1438             // skip write default erroneous data reporting if not supported
1439             if (hci_stack->local_supported_commands[0] & 0x08) break;
1440             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1441             // explicit fall through to reduce repetitions
1442 
1443         case HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1444             if (!hci_le_supported()){
1445                 // SKIP LE init for Classic only configuration
1446                 hci_init_done();
1447                 return;
1448             }
1449             break;
1450 #else
1451         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1452             if (!hci_le_supported()){
1453                 // SKIP LE init for Classic only configuration
1454                 hci_init_done();
1455                 return;
1456             }
1457 #endif
1458             break;
1459         // Response to command before init done state -> init done
1460         case (HCI_INIT_DONE-1):
1461             hci_init_done();
1462             return;
1463 
1464         default:
1465             break;
1466     }
1467     hci_initializing_next_state();
1468 }
1469 
1470 static void event_handler(uint8_t *packet, int size){
1471 
1472     uint16_t event_length = packet[1];
1473 
1474     // assert packet is complete
1475     if (size != event_length + 2){
1476         log_error("hci.c: event_handler called with event packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
1477         return;
1478     }
1479 
1480     bd_addr_t addr;
1481     bd_addr_type_t addr_type;
1482     uint8_t link_type;
1483     hci_con_handle_t handle;
1484     hci_connection_t * conn;
1485     int i;
1486 
1487     // warnings
1488     (void) link_type;
1489 
1490     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
1491 
1492     switch (hci_event_packet_get_type(packet)) {
1493 
1494         case HCI_EVENT_COMMAND_COMPLETE:
1495             // get num cmd packets - limit to 1 to reduce complexity
1496             hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
1497 
1498             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_name)){
1499                 if (packet[5]) break;
1500                 // terminate, name 248 chars
1501                 packet[6+248] = 0;
1502                 log_info("local name: %s", &packet[6]);
1503             }
1504             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_buffer_size)){
1505                 // from offset 5
1506                 // status
1507                 // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
1508                 hci_stack->acl_data_packet_length = little_endian_read_16(packet, 6);
1509                 hci_stack->sco_data_packet_length = packet[8];
1510                 hci_stack->acl_packets_total_num  = little_endian_read_16(packet, 9);
1511                 hci_stack->sco_packets_total_num  = little_endian_read_16(packet, 11);
1512 
1513                 if (hci_stack->state == HCI_STATE_INITIALIZING){
1514                     // determine usable ACL payload size
1515                     if (HCI_ACL_PAYLOAD_SIZE < hci_stack->acl_data_packet_length){
1516                         hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
1517                     }
1518                     log_info("hci_read_buffer_size: acl used size %u, count %u / sco size %u, count %u",
1519                              hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
1520                              hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
1521                 }
1522             }
1523 #ifdef ENABLE_BLE
1524             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_buffer_size)){
1525                 hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
1526                 hci_stack->le_acl_packets_total_num  = packet[8];
1527                     // determine usable ACL payload size
1528                     if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
1529                         hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
1530                     }
1531                 log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
1532             }
1533 #ifdef ENABLE_LE_CENTRAL
1534             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_white_list_size)){
1535                 hci_stack->le_whitelist_capacity = packet[6];
1536                 log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
1537             }
1538 #endif
1539 #endif
1540             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_bd_addr)) {
1541                 reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1],
1542 				hci_stack->local_bd_addr);
1543                 log_info("Local Address, Status: 0x%02x: Addr: %s",
1544                     packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE], bd_addr_to_str(hci_stack->local_bd_addr));
1545 #ifdef ENABLE_CLASSIC
1546                 if (hci_stack->link_key_db){
1547                     hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
1548                 }
1549 #endif
1550             }
1551 #ifdef ENABLE_CLASSIC
1552             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)){
1553                 hci_emit_discoverable_enabled(hci_stack->discoverable);
1554             }
1555 #endif
1556 
1557             // Note: HCI init checks
1558             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_supported_features)){
1559                 memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 8);
1560 
1561 #ifdef ENABLE_CLASSIC
1562                 // determine usable ACL packet types based on host buffer size and supported features
1563                 hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
1564                 log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
1565 #endif
1566                 // Classic/LE
1567                 log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
1568             }
1569             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_version_information)){
1570                 // hci_stack->hci_version    = little_endian_read_16(packet, 4);
1571                 // hci_stack->hci_revision   = little_endian_read_16(packet, 6);
1572                 // hci_stack->lmp_version    = little_endian_read_16(packet, 8);
1573                 hci_stack->manufacturer   = little_endian_read_16(packet, 10);
1574                 // hci_stack->lmp_subversion = little_endian_read_16(packet, 12);
1575                 log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
1576             }
1577             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_supported_commands)){
1578                 hci_stack->local_supported_commands[0] =
1579                     (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+14] & 0x80) >> 7 |  // bit 0 = Octet 14, bit 7
1580                     (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+24] & 0x40) >> 5 |  // bit 1 = Octet 24, bit 6
1581                     (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+10] & 0x10) >> 2 |  // bit 2 = Octet 10, bit 4
1582                     (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+18] & 0x08);        // bit 3 = Octet 18, bit 3
1583                     log_info("Local supported commands summary 0x%02x", hci_stack->local_supported_commands[0]);
1584             }
1585 #ifdef ENABLE_CLASSIC
1586             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_synchronous_flow_control_enable)){
1587                 if (packet[5] == 0){
1588                     hci_stack->synchronous_flow_control_enabled = 1;
1589                 }
1590             }
1591 #endif
1592             break;
1593 
1594         case HCI_EVENT_COMMAND_STATUS:
1595             // get num cmd packets - limit to 1 to reduce complexity
1596             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
1597             break;
1598 
1599         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
1600             int offset = 3;
1601             for (i=0; i<packet[2];i++){
1602                 handle = little_endian_read_16(packet, offset);
1603                 offset += 2;
1604                 uint16_t num_packets = little_endian_read_16(packet, offset);
1605                 offset += 2;
1606 
1607                 conn = hci_connection_for_handle(handle);
1608                 if (!conn){
1609                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
1610                     continue;
1611                 }
1612 
1613                 if (conn->address_type == BD_ADDR_TYPE_SCO){
1614 #ifdef ENABLE_CLASSIC
1615                     if (conn->num_sco_packets_sent >= num_packets){
1616                         conn->num_sco_packets_sent -= num_packets;
1617                     } else {
1618                         log_error("hci_number_completed_packets, more sco slots freed then sent.");
1619                         conn->num_sco_packets_sent = 0;
1620                     }
1621                     hci_notify_if_sco_can_send_now();
1622 #endif
1623                 } else {
1624                     if (conn->num_acl_packets_sent >= num_packets){
1625                         conn->num_acl_packets_sent -= num_packets;
1626                     } else {
1627                         log_error("hci_number_completed_packets, more acl slots freed then sent.");
1628                         conn->num_acl_packets_sent = 0;
1629                     }
1630                 }
1631                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_acl_packets_sent);
1632             }
1633             break;
1634         }
1635 
1636 #ifdef ENABLE_CLASSIC
1637         case HCI_EVENT_CONNECTION_REQUEST:
1638             reverse_bd_addr(&packet[2], addr);
1639             // TODO: eval COD 8-10
1640             link_type = packet[11];
1641             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), link_type);
1642             addr_type = link_type == 1 ? BD_ADDR_TYPE_CLASSIC : BD_ADDR_TYPE_SCO;
1643             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
1644             if (!conn) {
1645                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
1646             }
1647             if (!conn) {
1648                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
1649                 hci_stack->decline_reason = 0x0d;
1650                 bd_addr_copy(hci_stack->decline_addr, addr);
1651                 break;
1652             }
1653             conn->role  = HCI_ROLE_SLAVE;
1654             conn->state = RECEIVED_CONNECTION_REQUEST;
1655             // store info about eSCO
1656             if (link_type == 0x02){
1657                 conn->remote_supported_feature_eSCO = 1;
1658             }
1659             hci_run();
1660             break;
1661 
1662         case HCI_EVENT_CONNECTION_COMPLETE:
1663             // Connection management
1664             reverse_bd_addr(&packet[5], addr);
1665             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
1666             addr_type = BD_ADDR_TYPE_CLASSIC;
1667             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
1668             if (conn) {
1669                 if (!packet[2]){
1670                     conn->state = OPEN;
1671                     conn->con_handle = little_endian_read_16(packet, 3);
1672                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES;
1673 
1674                     // restart timer
1675                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
1676                     btstack_run_loop_add_timer(&conn->timeout);
1677 
1678                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
1679 
1680                     hci_emit_nr_connections_changed();
1681                 } else {
1682                     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
1683                     uint8_t status = packet[2];
1684                     bd_addr_t bd_address;
1685                     memcpy(&bd_address, conn->address, 6);
1686 
1687                     // connection failed, remove entry
1688                     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1689                     btstack_memory_hci_connection_free( conn );
1690 
1691                     // notify client if dedicated bonding
1692                     if (notify_dedicated_bonding_failed){
1693                         log_info("hci notify_dedicated_bonding_failed");
1694                         hci_emit_dedicated_bonding_result(bd_address, status);
1695                     }
1696 
1697                     // if authentication error, also delete link key
1698                     if (packet[2] == 0x05) {
1699                         gap_drop_link_key_for_bd_addr(addr);
1700                     }
1701                 }
1702             }
1703             break;
1704 
1705         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
1706             reverse_bd_addr(&packet[5], addr);
1707             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
1708             if (packet[2]){
1709                 // connection failed
1710                 break;
1711             }
1712             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
1713             if (!conn) {
1714                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
1715             }
1716             if (!conn) {
1717                 break;
1718             }
1719             conn->state = OPEN;
1720             conn->con_handle = little_endian_read_16(packet, 3);
1721             break;
1722 
1723         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
1724             handle = little_endian_read_16(packet, 3);
1725             conn = hci_connection_for_handle(handle);
1726             if (!conn) break;
1727             if (!packet[2]){
1728                 uint8_t * features = &packet[5];
1729                 if (features[6] & (1 << 3)){
1730                     conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP;
1731                 }
1732                 if (features[3] & (1<<7)){
1733                     conn->remote_supported_feature_eSCO = 1;
1734                 }
1735             }
1736             conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
1737             log_info("HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE, bonding flags %x, eSCO %u", conn->bonding_flags, conn->remote_supported_feature_eSCO);
1738             if (conn->bonding_flags & BONDING_DEDICATED){
1739                 conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
1740             }
1741             break;
1742 
1743         case HCI_EVENT_LINK_KEY_REQUEST:
1744             log_info("HCI_EVENT_LINK_KEY_REQUEST");
1745             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_REQUEST);
1746             // non-bondable mode: link key negative reply will be sent by HANDLE_LINK_KEY_REQUEST
1747             if (hci_stack->bondable && !hci_stack->link_key_db) break;
1748             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], HANDLE_LINK_KEY_REQUEST);
1749             hci_run();
1750             // request handled by hci_run() as HANDLE_LINK_KEY_REQUEST gets set
1751             return;
1752 
1753         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
1754             reverse_bd_addr(&packet[2], addr);
1755             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
1756             if (!conn) break;
1757             conn->authentication_flags |= RECV_LINK_KEY_NOTIFICATION;
1758             link_key_type_t link_key_type = (link_key_type_t)packet[24];
1759             // Change Connection Encryption keeps link key type
1760             if (link_key_type != CHANGED_COMBINATION_KEY){
1761                 conn->link_key_type = link_key_type;
1762             }
1763             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
1764             // still forward event to allow dismiss of pairing dialog
1765             break;
1766         }
1767 
1768         case HCI_EVENT_PIN_CODE_REQUEST:
1769             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], LEGACY_PAIRING_ACTIVE);
1770             // non-bondable mode: pin code negative reply will be sent
1771             if (!hci_stack->bondable){
1772                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], DENY_PIN_CODE_REQUEST);
1773                 hci_run();
1774                 return;
1775             }
1776             // PIN CODE REQUEST means the link key request didn't succee -> delete stored link key
1777             if (!hci_stack->link_key_db) break;
1778             hci_event_pin_code_request_get_bd_addr(packet, addr);
1779             hci_stack->link_key_db->delete_link_key(addr);
1780             break;
1781 
1782         case HCI_EVENT_IO_CAPABILITY_REQUEST:
1783             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_IO_CAPABILITIES_REQUEST);
1784             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_IO_CAPABILITIES_REPLY);
1785             break;
1786 
1787         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
1788             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
1789             if (!hci_stack->ssp_auto_accept) break;
1790             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_CONFIRM_REPLY);
1791             break;
1792 
1793         case HCI_EVENT_USER_PASSKEY_REQUEST:
1794             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
1795             if (!hci_stack->ssp_auto_accept) break;
1796             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_PASSKEY_REPLY);
1797             break;
1798 #endif
1799 
1800         case HCI_EVENT_ENCRYPTION_CHANGE:
1801             handle = little_endian_read_16(packet, 3);
1802             conn = hci_connection_for_handle(handle);
1803             if (!conn) break;
1804             if (packet[2] == 0) {
1805                 if (packet[5]){
1806                     conn->authentication_flags |= CONNECTION_ENCRYPTED;
1807                 } else {
1808                     conn->authentication_flags &= ~CONNECTION_ENCRYPTED;
1809                 }
1810             }
1811 #ifdef ENABLE_CLASSIC
1812             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
1813 #endif
1814             break;
1815 
1816 #ifdef ENABLE_CLASSIC
1817         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
1818             handle = little_endian_read_16(packet, 3);
1819             conn = hci_connection_for_handle(handle);
1820             if (!conn) break;
1821 
1822             // dedicated bonding: send result and disconnect
1823             if (conn->bonding_flags & BONDING_DEDICATED){
1824                 conn->bonding_flags &= ~BONDING_DEDICATED;
1825                 conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
1826                 conn->bonding_status = packet[2];
1827                 break;
1828             }
1829 
1830             if (packet[2] == 0 && gap_security_level_for_link_key_type(conn->link_key_type) >= conn->requested_security_level){
1831                 // link key sufficient for requested security
1832                 conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
1833                 break;
1834             }
1835             // not enough
1836             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
1837             break;
1838 #endif
1839 
1840         // HCI_EVENT_DISCONNECTION_COMPLETE
1841         // has been split, to first notify stack before shutting connection down
1842         // see end of function, too.
1843         case HCI_EVENT_DISCONNECTION_COMPLETE:
1844             if (packet[2]) break;   // status != 0
1845             handle = little_endian_read_16(packet, 3);
1846             // drop outgoing ACL fragments if it is for closed connection
1847             if (hci_stack->acl_fragmentation_total_size > 0) {
1848                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
1849                     log_info("hci: drop fragmented ACL data for closed connection");
1850                      hci_stack->acl_fragmentation_total_size = 0;
1851                      hci_stack->acl_fragmentation_pos = 0;
1852                 }
1853             }
1854 
1855             // re-enable advertisements for le connections if active
1856             conn = hci_connection_for_handle(handle);
1857             if (!conn) break;
1858 #ifdef ENABLE_BLE
1859 #ifdef ENABLE_LE_PERIPHERAL
1860             if (hci_is_le_connection(conn) && hci_stack->le_advertisements_enabled){
1861                 hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
1862             }
1863 #endif
1864 #endif
1865             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
1866             break;
1867 
1868         case HCI_EVENT_HARDWARE_ERROR:
1869             log_error("Hardware Error: 0x%02x", packet[2]);
1870             if (hci_stack->hardware_error_callback){
1871                 (*hci_stack->hardware_error_callback)(packet[2]);
1872             } else {
1873                 // if no special requests, just reboot stack
1874                 hci_power_control_off();
1875                 hci_power_control_on();
1876             }
1877             break;
1878 
1879 #ifdef ENABLE_CLASSIC
1880         case HCI_EVENT_ROLE_CHANGE:
1881             if (packet[2]) break;   // status != 0
1882             handle = little_endian_read_16(packet, 3);
1883             conn = hci_connection_for_handle(handle);
1884             if (!conn) break;       // no conn
1885             conn->role = packet[9];
1886             break;
1887 #endif
1888 
1889         case HCI_EVENT_TRANSPORT_PACKET_SENT:
1890             // release packet buffer only for asynchronous transport and if there are not further fragements
1891             if (hci_transport_synchronous()) {
1892                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
1893                 return; // instead of break: to avoid re-entering hci_run()
1894             }
1895             if (hci_stack->acl_fragmentation_total_size) break;
1896             hci_release_packet_buffer();
1897 
1898             // L2CAP receives this event via the hci_emit_event below
1899 
1900 #ifdef ENABLE_CLASSIC
1901             // For SCO, we do the can_send_now_check here
1902             hci_notify_if_sco_can_send_now();
1903 #endif
1904             break;
1905 
1906 #ifdef ENABLE_CLASSIC
1907         case HCI_EVENT_SCO_CAN_SEND_NOW:
1908             // For SCO, we do the can_send_now_check here
1909             hci_notify_if_sco_can_send_now();
1910             return;
1911 #endif
1912 
1913 #ifdef ENABLE_BLE
1914         case HCI_EVENT_LE_META:
1915             switch (packet[2]){
1916 #ifdef ENABLE_LE_CENTRAL
1917                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
1918                     // log_info("advertising report received");
1919                     if (hci_stack->le_scanning_state != LE_SCANNING) break;
1920                     le_handle_advertisement_report(packet, size);
1921                     break;
1922 #endif
1923                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
1924                     // Connection management
1925                     reverse_bd_addr(&packet[8], addr);
1926                     addr_type = (bd_addr_type_t)packet[7];
1927                     log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
1928                     conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
1929 #ifdef ENABLE_LE_CENTRAL
1930                     // if auto-connect, remove from whitelist in both roles
1931                     if (hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST){
1932                         hci_remove_from_whitelist(addr_type, addr);
1933                     }
1934                     // handle error: error is reported only to the initiator -> outgoing connection
1935                     if (packet[3]){
1936                         // outgoing connection establishment is done
1937                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
1938                         // remove entry
1939                         if (conn){
1940                             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1941                             btstack_memory_hci_connection_free( conn );
1942                         }
1943                         break;
1944                     }
1945 #endif
1946                     // on success, both hosts receive connection complete event
1947                     if (packet[6] == HCI_ROLE_MASTER){
1948 #ifdef ENABLE_LE_CENTRAL
1949                         // if we're master, it was an outgoing connection and we're done with it
1950                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
1951 #endif
1952                     } else {
1953 #ifdef ENABLE_LE_PERIPHERAL
1954                         // if we're slave, it was an incoming connection, advertisements have stopped
1955                         hci_stack->le_advertisements_active = 0;
1956                         // try to re-enable them
1957                         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
1958 #endif
1959                     }
1960                     // LE connections are auto-accepted, so just create a connection if there isn't one already
1961                     if (!conn){
1962                         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
1963                     }
1964                     // no memory, sorry.
1965                     if (!conn){
1966                         break;
1967                     }
1968 
1969                     conn->state = OPEN;
1970                     conn->role  = packet[6];
1971                     conn->con_handle = little_endian_read_16(packet, 4);
1972 
1973                     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
1974 
1975                     // restart timer
1976                     // btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
1977                     // btstack_run_loop_add_timer(&conn->timeout);
1978 
1979                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
1980 
1981                     hci_emit_nr_connections_changed();
1982                     break;
1983 
1984             // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
1985 
1986                 default:
1987                     break;
1988             }
1989             break;
1990 #endif
1991         default:
1992             break;
1993     }
1994 
1995     // handle BT initialization
1996     if (hci_stack->state == HCI_STATE_INITIALIZING){
1997         hci_initializing_event_handler(packet, size);
1998     }
1999 
2000     // help with BT sleep
2001     if (hci_stack->state == HCI_STATE_FALLING_ASLEEP
2002         && hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE
2003         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)){
2004         hci_initializing_next_state();
2005     }
2006 
2007     // notify upper stack
2008 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
2009 
2010     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
2011     if (hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE){
2012         if (!packet[2]){
2013             handle = little_endian_read_16(packet, 3);
2014             hci_connection_t * aConn = hci_connection_for_handle(handle);
2015             if (aConn) {
2016                 uint8_t status = aConn->bonding_status;
2017                 uint16_t flags = aConn->bonding_flags;
2018                 bd_addr_t bd_address;
2019                 memcpy(&bd_address, aConn->address, 6);
2020                 hci_shutdown_connection(aConn);
2021                 // connection struct is gone, don't access anymore
2022                 if (flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
2023                     hci_emit_dedicated_bonding_result(bd_address, status);
2024                 }
2025             }
2026         }
2027     }
2028 
2029 	// execute main loop
2030 	hci_run();
2031 }
2032 
2033 #ifdef ENABLE_CLASSIC
2034 static void sco_handler(uint8_t * packet, uint16_t size){
2035     if (!hci_stack->sco_packet_handler) return;
2036     hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
2037 }
2038 #endif
2039 
2040 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
2041     hci_dump_packet(packet_type, 1, packet, size);
2042     switch (packet_type) {
2043         case HCI_EVENT_PACKET:
2044             event_handler(packet, size);
2045             break;
2046         case HCI_ACL_DATA_PACKET:
2047             acl_handler(packet, size);
2048             break;
2049 #ifdef ENABLE_CLASSIC
2050         case HCI_SCO_DATA_PACKET:
2051             sco_handler(packet, size);
2052             break;
2053 #endif
2054         default:
2055             break;
2056     }
2057 }
2058 
2059 /**
2060  * @brief Add event packet handler.
2061  */
2062 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
2063     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
2064 }
2065 
2066 
2067 /** Register HCI packet handlers */
2068 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
2069     hci_stack->acl_packet_handler = handler;
2070 }
2071 
2072 #ifdef ENABLE_CLASSIC
2073 /**
2074  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
2075  */
2076 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
2077     hci_stack->sco_packet_handler = handler;
2078 }
2079 #endif
2080 
2081 static void hci_state_reset(void){
2082     // no connections yet
2083     hci_stack->connections = NULL;
2084 
2085     // keep discoverable/connectable as this has been requested by the client(s)
2086     // hci_stack->discoverable = 0;
2087     // hci_stack->connectable = 0;
2088     // hci_stack->bondable = 1;
2089     // hci_stack->own_addr_type = 0;
2090 
2091     // buffer is free
2092     hci_stack->hci_packet_buffer_reserved = 0;
2093 
2094     // no pending cmds
2095     hci_stack->decline_reason = 0;
2096     hci_stack->new_scan_enable_value = 0xff;
2097 
2098     // LE
2099 #ifdef ENABLE_BLE
2100     memset(hci_stack->le_random_address, 0, 6);
2101     hci_stack->le_random_address_set = 0;
2102 #endif
2103 #ifdef ENABLE_LE_CENTRAL
2104     hci_stack->le_scanning_state = LE_SCAN_IDLE;
2105     hci_stack->le_scan_type = 0xff;
2106     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2107     hci_stack->le_whitelist = 0;
2108     hci_stack->le_whitelist_capacity = 0;
2109 #endif
2110 
2111     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
2112     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
2113     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
2114     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
2115     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
2116     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
2117 }
2118 
2119 #ifdef ENABLE_CLASSIC
2120 /**
2121  * @brief Configure Bluetooth hardware control. Has to be called before power on.
2122  */
2123 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
2124     // store and open remote device db
2125     hci_stack->link_key_db = link_key_db;
2126     if (hci_stack->link_key_db) {
2127         hci_stack->link_key_db->open();
2128     }
2129 }
2130 #endif
2131 
2132 void hci_init(const hci_transport_t *transport, const void *config){
2133 
2134 #ifdef HAVE_MALLOC
2135     if (!hci_stack) {
2136         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
2137     }
2138 #else
2139     hci_stack = &hci_stack_static;
2140 #endif
2141     memset(hci_stack, 0, sizeof(hci_stack_t));
2142 
2143     // reference to use transport layer implementation
2144     hci_stack->hci_transport = transport;
2145 
2146     // reference to used config
2147     hci_stack->config = config;
2148 
2149     // setup pointer for outgoing packet buffer
2150     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
2151 
2152     // max acl payload size defined in config.h
2153     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
2154 
2155     // register packet handlers with transport
2156     transport->register_packet_handler(&packet_handler);
2157 
2158     hci_stack->state = HCI_STATE_OFF;
2159 
2160     // class of device
2161     hci_stack->class_of_device = 0x007a020c; // Smartphone
2162 
2163     // bondable by default
2164     hci_stack->bondable = 1;
2165 
2166     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
2167     hci_stack->ssp_enable = 1;
2168     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
2169     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
2170     hci_stack->ssp_auto_accept = 1;
2171 
2172     // voice setting - signed 8 bit pcm data with CVSD over the air
2173     hci_stack->sco_voice_setting = 0x40;
2174 
2175     hci_state_reset();
2176 }
2177 
2178 /**
2179  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
2180  */
2181 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
2182     hci_stack->chipset = chipset_driver;
2183 
2184     // reset chipset driver - init is also called on power_up
2185     if (hci_stack->chipset && hci_stack->chipset->init){
2186         hci_stack->chipset->init(hci_stack->config);
2187     }
2188 }
2189 
2190 /**
2191  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
2192  */
2193 void hci_set_control(const btstack_control_t *hardware_control){
2194     // references to used control implementation
2195     hci_stack->control = hardware_control;
2196     // init with transport config
2197     hardware_control->init(hci_stack->config);
2198 }
2199 
2200 void hci_close(void){
2201     // close remote device db
2202     if (hci_stack->link_key_db) {
2203         hci_stack->link_key_db->close();
2204     }
2205 
2206     btstack_linked_list_iterator_t lit;
2207     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
2208     while (btstack_linked_list_iterator_has_next(&lit)){
2209         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
2210         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
2211         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
2212         hci_shutdown_connection(connection);
2213     }
2214 
2215     hci_power_control(HCI_POWER_OFF);
2216 
2217 #ifdef HAVE_MALLOC
2218     free(hci_stack);
2219 #endif
2220     hci_stack = NULL;
2221 }
2222 
2223 #ifdef ENABLE_CLASSIC
2224 void gap_set_class_of_device(uint32_t class_of_device){
2225     hci_stack->class_of_device = class_of_device;
2226 }
2227 
2228 void hci_disable_l2cap_timeout_check(void){
2229     disable_l2cap_timeouts = 1;
2230 }
2231 #endif
2232 
2233 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
2234 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
2235 void hci_set_bd_addr(bd_addr_t addr){
2236     memcpy(hci_stack->custom_bd_addr, addr, 6);
2237     hci_stack->custom_bd_addr_set = 1;
2238 }
2239 #endif
2240 
2241 // State-Module-Driver overview
2242 // state                    module  low-level
2243 // HCI_STATE_OFF             off      close
2244 // HCI_STATE_INITIALIZING,   on       open
2245 // HCI_STATE_WORKING,        on       open
2246 // HCI_STATE_HALTING,        on       open
2247 // HCI_STATE_SLEEPING,    off/sleep   close
2248 // HCI_STATE_FALLING_ASLEEP  on       open
2249 
2250 static int hci_power_control_on(void){
2251 
2252     // power on
2253     int err = 0;
2254     if (hci_stack->control && hci_stack->control->on){
2255         err = (*hci_stack->control->on)();
2256     }
2257     if (err){
2258         log_error( "POWER_ON failed");
2259         hci_emit_hci_open_failed();
2260         return err;
2261     }
2262 
2263     // int chipset driver
2264     if (hci_stack->chipset && hci_stack->chipset->init){
2265         hci_stack->chipset->init(hci_stack->config);
2266     }
2267 
2268     // init transport
2269     if (hci_stack->hci_transport->init){
2270         hci_stack->hci_transport->init(hci_stack->config);
2271     }
2272 
2273     // open transport
2274     err = hci_stack->hci_transport->open();
2275     if (err){
2276         log_error( "HCI_INIT failed, turning Bluetooth off again");
2277         if (hci_stack->control && hci_stack->control->off){
2278             (*hci_stack->control->off)();
2279         }
2280         hci_emit_hci_open_failed();
2281         return err;
2282     }
2283     return 0;
2284 }
2285 
2286 static void hci_power_control_off(void){
2287 
2288     log_info("hci_power_control_off");
2289 
2290     // close low-level device
2291     hci_stack->hci_transport->close();
2292 
2293     log_info("hci_power_control_off - hci_transport closed");
2294 
2295     // power off
2296     if (hci_stack->control && hci_stack->control->off){
2297         (*hci_stack->control->off)();
2298     }
2299 
2300     log_info("hci_power_control_off - control closed");
2301 
2302     hci_stack->state = HCI_STATE_OFF;
2303 }
2304 
2305 static void hci_power_control_sleep(void){
2306 
2307     log_info("hci_power_control_sleep");
2308 
2309 #if 0
2310     // don't close serial port during sleep
2311 
2312     // close low-level device
2313     hci_stack->hci_transport->close(hci_stack->config);
2314 #endif
2315 
2316     // sleep mode
2317     if (hci_stack->control && hci_stack->control->sleep){
2318         (*hci_stack->control->sleep)();
2319     }
2320 
2321     hci_stack->state = HCI_STATE_SLEEPING;
2322 }
2323 
2324 static int hci_power_control_wake(void){
2325 
2326     log_info("hci_power_control_wake");
2327 
2328     // wake on
2329     if (hci_stack->control && hci_stack->control->wake){
2330         (*hci_stack->control->wake)();
2331     }
2332 
2333 #if 0
2334     // open low-level device
2335     int err = hci_stack->hci_transport->open(hci_stack->config);
2336     if (err){
2337         log_error( "HCI_INIT failed, turning Bluetooth off again");
2338         if (hci_stack->control && hci_stack->control->off){
2339             (*hci_stack->control->off)();
2340         }
2341         hci_emit_hci_open_failed();
2342         return err;
2343     }
2344 #endif
2345 
2346     return 0;
2347 }
2348 
2349 static void hci_power_transition_to_initializing(void){
2350     // set up state machine
2351     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
2352     hci_stack->hci_packet_buffer_reserved = 0;
2353     hci_stack->state = HCI_STATE_INITIALIZING;
2354     hci_stack->substate = HCI_INIT_SEND_RESET;
2355 }
2356 
2357 int hci_power_control(HCI_POWER_MODE power_mode){
2358 
2359     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
2360 
2361     int err = 0;
2362     switch (hci_stack->state){
2363 
2364         case HCI_STATE_OFF:
2365             switch (power_mode){
2366                 case HCI_POWER_ON:
2367                     err = hci_power_control_on();
2368                     if (err) {
2369                         log_error("hci_power_control_on() error %d", err);
2370                         return err;
2371                     }
2372                     hci_power_transition_to_initializing();
2373                     break;
2374                 case HCI_POWER_OFF:
2375                     // do nothing
2376                     break;
2377                 case HCI_POWER_SLEEP:
2378                     // do nothing (with SLEEP == OFF)
2379                     break;
2380             }
2381             break;
2382 
2383         case HCI_STATE_INITIALIZING:
2384             switch (power_mode){
2385                 case HCI_POWER_ON:
2386                     // do nothing
2387                     break;
2388                 case HCI_POWER_OFF:
2389                     // no connections yet, just turn it off
2390                     hci_power_control_off();
2391                     break;
2392                 case HCI_POWER_SLEEP:
2393                     // no connections yet, just turn it off
2394                     hci_power_control_sleep();
2395                     break;
2396             }
2397             break;
2398 
2399         case HCI_STATE_WORKING:
2400             switch (power_mode){
2401                 case HCI_POWER_ON:
2402                     // do nothing
2403                     break;
2404                 case HCI_POWER_OFF:
2405                     // see hci_run
2406                     hci_stack->state = HCI_STATE_HALTING;
2407                     break;
2408                 case HCI_POWER_SLEEP:
2409                     // see hci_run
2410                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
2411                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
2412                     break;
2413             }
2414             break;
2415 
2416         case HCI_STATE_HALTING:
2417             switch (power_mode){
2418                 case HCI_POWER_ON:
2419                     hci_power_transition_to_initializing();
2420                     break;
2421                 case HCI_POWER_OFF:
2422                     // do nothing
2423                     break;
2424                 case HCI_POWER_SLEEP:
2425                     // see hci_run
2426                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
2427                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
2428                     break;
2429             }
2430             break;
2431 
2432         case HCI_STATE_FALLING_ASLEEP:
2433             switch (power_mode){
2434                 case HCI_POWER_ON:
2435 
2436 #ifdef HAVE_PLATFORM_IPHONE_OS
2437                     // nothing to do, if H4 supports power management
2438                     if (btstack_control_iphone_power_management_enabled()){
2439                         hci_stack->state = HCI_STATE_INITIALIZING;
2440                         hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;   // init after sleep
2441                         break;
2442                     }
2443 #endif
2444                     hci_power_transition_to_initializing();
2445                     break;
2446                 case HCI_POWER_OFF:
2447                     // see hci_run
2448                     hci_stack->state = HCI_STATE_HALTING;
2449                     break;
2450                 case HCI_POWER_SLEEP:
2451                     // do nothing
2452                     break;
2453             }
2454             break;
2455 
2456         case HCI_STATE_SLEEPING:
2457             switch (power_mode){
2458                 case HCI_POWER_ON:
2459 
2460 #ifdef HAVE_PLATFORM_IPHONE_OS
2461                     // nothing to do, if H4 supports power management
2462                     if (btstack_control_iphone_power_management_enabled()){
2463                         hci_stack->state = HCI_STATE_INITIALIZING;
2464                         hci_stack->substate = HCI_INIT_AFTER_SLEEP;
2465                         hci_update_scan_enable();
2466                         break;
2467                     }
2468 #endif
2469                     err = hci_power_control_wake();
2470                     if (err) return err;
2471                     hci_power_transition_to_initializing();
2472                     break;
2473                 case HCI_POWER_OFF:
2474                     hci_stack->state = HCI_STATE_HALTING;
2475                     break;
2476                 case HCI_POWER_SLEEP:
2477                     // do nothing
2478                     break;
2479             }
2480             break;
2481     }
2482 
2483     // create internal event
2484 	hci_emit_state();
2485 
2486 	// trigger next/first action
2487 	hci_run();
2488 
2489     return 0;
2490 }
2491 
2492 
2493 #ifdef ENABLE_CLASSIC
2494 
2495 static void hci_update_scan_enable(void){
2496     // 2 = page scan, 1 = inq scan
2497     hci_stack->new_scan_enable_value  = hci_stack->connectable << 1 | hci_stack->discoverable;
2498     hci_run();
2499 }
2500 
2501 void gap_discoverable_control(uint8_t enable){
2502     if (enable) enable = 1; // normalize argument
2503 
2504     if (hci_stack->discoverable == enable){
2505         hci_emit_discoverable_enabled(hci_stack->discoverable);
2506         return;
2507     }
2508 
2509     hci_stack->discoverable = enable;
2510     hci_update_scan_enable();
2511 }
2512 
2513 void gap_connectable_control(uint8_t enable){
2514     if (enable) enable = 1; // normalize argument
2515 
2516     // don't emit event
2517     if (hci_stack->connectable == enable) return;
2518 
2519     hci_stack->connectable = enable;
2520     hci_update_scan_enable();
2521 }
2522 #endif
2523 
2524 void gap_local_bd_addr(bd_addr_t address_buffer){
2525     memcpy(address_buffer, hci_stack->local_bd_addr, 6);
2526 }
2527 
2528 static void hci_run(void){
2529 
2530     // log_info("hci_run: entered");
2531     btstack_linked_item_t * it;
2532 
2533     // send continuation fragments first, as they block the prepared packet buffer
2534     if (hci_stack->acl_fragmentation_total_size > 0) {
2535         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
2536         hci_connection_t *connection = hci_connection_for_handle(con_handle);
2537         if (connection) {
2538             if (hci_can_send_prepared_acl_packet_now(con_handle)){
2539                 hci_send_acl_packet_fragments(connection);
2540                 return;
2541             }
2542         } else {
2543             // connection gone -> discard further fragments
2544             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
2545             hci_stack->acl_fragmentation_total_size = 0;
2546             hci_stack->acl_fragmentation_pos = 0;
2547         }
2548     }
2549 
2550     if (!hci_can_send_command_packet_now()) return;
2551 
2552     // global/non-connection oriented commands
2553 
2554 #ifdef ENABLE_CLASSIC
2555     // decline incoming connections
2556     if (hci_stack->decline_reason){
2557         uint8_t reason = hci_stack->decline_reason;
2558         hci_stack->decline_reason = 0;
2559         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
2560         return;
2561     }
2562 
2563     // send scan enable
2564     if (hci_stack->state == HCI_STATE_WORKING && hci_stack->new_scan_enable_value != 0xff && hci_classic_supported()){
2565         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
2566         hci_stack->new_scan_enable_value = 0xff;
2567         return;
2568     }
2569 #endif
2570 
2571 #ifdef ENABLE_BLE
2572     // advertisements, active scanning, and creating connections requires randaom address to be set if using private address
2573     if ((hci_stack->state == HCI_STATE_WORKING)
2574     && (hci_stack->le_own_addr_type == BD_ADDR_TYPE_LE_PUBLIC || hci_stack->le_random_address_set)){
2575 
2576 #ifdef ENABLE_LE_CENTRAL
2577         // handle le scan
2578         switch(hci_stack->le_scanning_state){
2579             case LE_START_SCAN:
2580                 hci_stack->le_scanning_state = LE_SCANNING;
2581                 hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
2582                 return;
2583 
2584             case LE_STOP_SCAN:
2585                 hci_stack->le_scanning_state = LE_SCAN_IDLE;
2586                 hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
2587                 return;
2588             default:
2589                 break;
2590         }
2591         if (hci_stack->le_scan_type != 0xff){
2592             // defaults: active scanning, accept all advertisement packets
2593             int scan_type = hci_stack->le_scan_type;
2594             hci_stack->le_scan_type = 0xff;
2595             hci_send_cmd(&hci_le_set_scan_parameters, scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window, hci_stack->le_own_addr_type, 0);
2596             return;
2597         }
2598 #endif
2599 #ifdef ENABLE_LE_PERIPHERAL
2600         // le advertisement control
2601         if (hci_stack->le_advertisements_todo){
2602             log_info("hci_run: gap_le: adv todo: %x", hci_stack->le_advertisements_todo );
2603         }
2604         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_DISABLE){
2605             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_DISABLE;
2606             hci_send_cmd(&hci_le_set_advertise_enable, 0);
2607             return;
2608         }
2609         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
2610             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
2611             hci_send_cmd(&hci_le_set_advertising_parameters,
2612                  hci_stack->le_advertisements_interval_min,
2613                  hci_stack->le_advertisements_interval_max,
2614                  hci_stack->le_advertisements_type,
2615                  hci_stack->le_own_addr_type,
2616                  hci_stack->le_advertisements_direct_address_type,
2617                  hci_stack->le_advertisements_direct_address,
2618                  hci_stack->le_advertisements_channel_map,
2619                  hci_stack->le_advertisements_filter_policy);
2620             return;
2621         }
2622         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
2623             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
2624             hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, hci_stack->le_advertisements_data);
2625             return;
2626         }
2627         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
2628             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
2629             hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len,
2630                 hci_stack->le_scan_response_data);
2631             return;
2632         }
2633         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_ENABLE){
2634             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_ENABLE;
2635             hci_send_cmd(&hci_le_set_advertise_enable, 1);
2636             return;
2637         }
2638 #endif
2639 
2640 #ifdef ENABLE_LE_CENTRAL
2641         //
2642         // LE Whitelist Management
2643         //
2644 
2645         // check if whitelist needs modification
2646         btstack_linked_list_iterator_t lit;
2647         int modification_pending = 0;
2648         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
2649         while (btstack_linked_list_iterator_has_next(&lit)){
2650             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
2651             if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
2652                 modification_pending = 1;
2653                 break;
2654             }
2655         }
2656 
2657         if (modification_pending){
2658             // stop connnecting if modification pending
2659             if (hci_stack->le_connecting_state != LE_CONNECTING_IDLE){
2660                 hci_send_cmd(&hci_le_create_connection_cancel);
2661                 return;
2662             }
2663 
2664             // add/remove entries
2665             btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
2666             while (btstack_linked_list_iterator_has_next(&lit)){
2667                 whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
2668                 if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
2669                     entry->state = LE_WHITELIST_ON_CONTROLLER;
2670                     hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
2671                     return;
2672 
2673                 }
2674                 if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
2675                     bd_addr_t address;
2676                     bd_addr_type_t address_type = entry->address_type;
2677                     memcpy(address, entry->address, 6);
2678                     btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
2679                     btstack_memory_whitelist_entry_free(entry);
2680                     hci_send_cmd(&hci_le_remove_device_from_white_list, address_type, address);
2681                     return;
2682                 }
2683             }
2684         }
2685 
2686         // start connecting
2687         if ( hci_stack->le_connecting_state == LE_CONNECTING_IDLE &&
2688             !btstack_linked_list_empty(&hci_stack->le_whitelist)){
2689             bd_addr_t null_addr;
2690             memset(null_addr, 0, 6);
2691             hci_send_cmd(&hci_le_create_connection,
2692                  0x0060,    // scan interval: 60 ms
2693                  0x0030,    // scan interval: 30 ms
2694                  1,         // use whitelist
2695                  0,         // peer address type
2696                  null_addr, // peer bd addr
2697                  hci_stack->le_own_addr_type, // our addr type:
2698                  0x0008,    // conn interval min
2699                  0x0018,    // conn interval max
2700                  0,         // conn latency
2701                  0x0048,    // supervision timeout
2702                  0x0001,    // min ce length
2703                  0x0001     // max ce length
2704                  );
2705             return;
2706         }
2707 #endif
2708     }
2709 #endif
2710 
2711     // send pending HCI commands
2712     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
2713         hci_connection_t * connection = (hci_connection_t *) it;
2714 
2715         switch(connection->state){
2716             case SEND_CREATE_CONNECTION:
2717                 switch(connection->address_type){
2718 #ifdef ENABLE_CLASSIC
2719                     case BD_ADDR_TYPE_CLASSIC:
2720                         log_info("sending hci_create_connection");
2721                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, 1);
2722                         break;
2723 #endif
2724                     default:
2725 #ifdef ENABLE_BLE
2726 #ifdef ENABLE_LE_CENTRAL
2727                         log_info("sending hci_le_create_connection");
2728                         hci_send_cmd(&hci_le_create_connection,
2729                                      0x0060,    // scan interval: 60 ms
2730                                      0x0030,    // scan interval: 30 ms
2731                                      0,         // don't use whitelist
2732                                      connection->address_type, // peer address type
2733                                      connection->address,      // peer bd addr
2734                                      hci_stack->le_own_addr_type,  // our addr type:
2735                                      0x0008,    // conn interval min
2736                                      0x0018,    // conn interval max
2737                                      0,         // conn latency
2738                                      0x0048,    // supervision timeout
2739                                      0x0001,    // min ce length
2740                                      0x0001     // max ce length
2741                                      );
2742 
2743                         connection->state = SENT_CREATE_CONNECTION;
2744 #endif
2745 #endif
2746                         break;
2747                 }
2748                 return;
2749 
2750 #ifdef ENABLE_CLASSIC
2751             case RECEIVED_CONNECTION_REQUEST:
2752                 log_info("sending hci_accept_connection_request, remote eSCO %u", connection->remote_supported_feature_eSCO);
2753                 connection->state = ACCEPTED_CONNECTION_REQUEST;
2754                 connection->role  = HCI_ROLE_SLAVE;
2755                 if (connection->address_type == BD_ADDR_TYPE_CLASSIC){
2756                     hci_send_cmd(&hci_accept_connection_request, connection->address, 1);
2757                 }
2758                 return;
2759 #endif
2760 
2761 #ifdef ENABLE_BLE
2762 #ifdef ENABLE_LE_CENTRAL
2763             case SEND_CANCEL_CONNECTION:
2764                 connection->state = SENT_CANCEL_CONNECTION;
2765                 hci_send_cmd(&hci_le_create_connection_cancel);
2766                 return;
2767 #endif
2768 #endif
2769             case SEND_DISCONNECT:
2770                 connection->state = SENT_DISCONNECT;
2771                 hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13); // remote closed connection
2772                 return;
2773 
2774             default:
2775                 break;
2776         }
2777 
2778 #ifdef ENABLE_CLASSIC
2779         if (connection->authentication_flags & HANDLE_LINK_KEY_REQUEST){
2780             log_info("responding to link key request");
2781             connectionClearAuthenticationFlags(connection, HANDLE_LINK_KEY_REQUEST);
2782             link_key_t link_key;
2783             link_key_type_t link_key_type;
2784             if ( hci_stack->link_key_db
2785               && hci_stack->link_key_db->get_link_key(connection->address, link_key, &link_key_type)
2786               && gap_security_level_for_link_key_type(link_key_type) >= connection->requested_security_level){
2787                connection->link_key_type = link_key_type;
2788                hci_send_cmd(&hci_link_key_request_reply, connection->address, &link_key);
2789             } else {
2790                hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
2791             }
2792             return;
2793         }
2794 
2795         if (connection->authentication_flags & DENY_PIN_CODE_REQUEST){
2796             log_info("denying to pin request");
2797             connectionClearAuthenticationFlags(connection, DENY_PIN_CODE_REQUEST);
2798             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
2799             return;
2800         }
2801 
2802         if (connection->authentication_flags & SEND_IO_CAPABILITIES_REPLY){
2803             connectionClearAuthenticationFlags(connection, SEND_IO_CAPABILITIES_REPLY);
2804             log_info("IO Capability Request received, stack bondable %u, io cap %u", hci_stack->bondable, hci_stack->ssp_io_capability);
2805             if (hci_stack->bondable && (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN)){
2806                 // tweak authentication requirements
2807                 uint8_t authreq = hci_stack->ssp_authentication_requirement;
2808                 if (connection->bonding_flags & BONDING_DEDICATED){
2809                     authreq = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
2810                 }
2811                 if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
2812                     authreq |= 1;
2813                 }
2814                 hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, NULL, authreq);
2815             } else {
2816                 hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
2817             }
2818             return;
2819         }
2820 
2821         if (connection->authentication_flags & SEND_USER_CONFIRM_REPLY){
2822             connectionClearAuthenticationFlags(connection, SEND_USER_CONFIRM_REPLY);
2823             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
2824             return;
2825         }
2826 
2827         if (connection->authentication_flags & SEND_USER_PASSKEY_REPLY){
2828             connectionClearAuthenticationFlags(connection, SEND_USER_PASSKEY_REPLY);
2829             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
2830             return;
2831         }
2832 
2833         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES){
2834             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES;
2835             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
2836             return;
2837         }
2838 
2839         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
2840             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
2841             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
2842             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // authentication done
2843             return;
2844         }
2845 
2846         if (connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST){
2847             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
2848             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
2849             return;
2850         }
2851 
2852         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
2853             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
2854             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
2855             return;
2856         }
2857 #endif
2858 
2859         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
2860             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
2861             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x0005);  // authentication failure
2862             return;
2863         }
2864 
2865 #ifdef ENABLE_BLE
2866         if (connection->le_con_parameter_update_state == CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS){
2867             connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
2868 
2869             uint16_t connection_interval_min = connection->le_conn_interval_min;
2870             connection->le_conn_interval_min = 0;
2871             hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection_interval_min,
2872                 connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
2873                 0x0000, 0xffff);
2874         }
2875 #endif
2876     }
2877 
2878     hci_connection_t * connection;
2879     switch (hci_stack->state){
2880         case HCI_STATE_INITIALIZING:
2881             hci_initializing_run();
2882             break;
2883 
2884         case HCI_STATE_HALTING:
2885 
2886             log_info("HCI_STATE_HALTING");
2887 
2888             // free whitelist entries
2889 #ifdef ENABLE_BLE
2890 #ifdef ENABLE_LE_CENTRAL
2891             {
2892                 btstack_linked_list_iterator_t lit;
2893                 btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
2894                 while (btstack_linked_list_iterator_has_next(&lit)){
2895                     whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
2896                     btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
2897                     btstack_memory_whitelist_entry_free(entry);
2898                 }
2899             }
2900 #endif
2901 #endif
2902             // close all open connections
2903             connection =  (hci_connection_t *) hci_stack->connections;
2904             if (connection){
2905                 hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
2906                 if (!hci_can_send_command_packet_now()) return;
2907 
2908                 log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
2909 
2910                 // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
2911                 hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
2912 
2913                 // ... which would be ignored anyway as we shutdown (free) the connection now
2914                 hci_shutdown_connection(connection);
2915 
2916                 // finally, send the disconnect command
2917                 hci_send_cmd(&hci_disconnect, con_handle, 0x13);  // remote closed connection
2918                 return;
2919             }
2920             log_info("HCI_STATE_HALTING, calling off");
2921 
2922             // switch mode
2923             hci_power_control_off();
2924 
2925             log_info("HCI_STATE_HALTING, emitting state");
2926             hci_emit_state();
2927             log_info("HCI_STATE_HALTING, done");
2928             break;
2929 
2930         case HCI_STATE_FALLING_ASLEEP:
2931             switch(hci_stack->substate) {
2932                 case HCI_FALLING_ASLEEP_DISCONNECT:
2933                     log_info("HCI_STATE_FALLING_ASLEEP");
2934                     // close all open connections
2935                     connection =  (hci_connection_t *) hci_stack->connections;
2936 
2937 #ifdef HAVE_PLATFORM_IPHONE_OS
2938                     // don't close connections, if H4 supports power management
2939                     if (btstack_control_iphone_power_management_enabled()){
2940                         connection = NULL;
2941                     }
2942 #endif
2943                     if (connection){
2944 
2945                         // send disconnect
2946                         if (!hci_can_send_command_packet_now()) return;
2947 
2948                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
2949                         hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // remote closed connection
2950 
2951                         // send disconnected event right away - causes higher layer connections to get closed, too.
2952                         hci_shutdown_connection(connection);
2953                         return;
2954                     }
2955 
2956                     if (hci_classic_supported()){
2957                         // disable page and inquiry scan
2958                         if (!hci_can_send_command_packet_now()) return;
2959 
2960                         log_info("HCI_STATE_HALTING, disabling inq scans");
2961                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
2962 
2963                         // continue in next sub state
2964                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
2965                         break;
2966                     }
2967                     // no break - fall through for ble-only chips
2968 
2969                 case HCI_FALLING_ASLEEP_COMPLETE:
2970                     log_info("HCI_STATE_HALTING, calling sleep");
2971 #ifdef HAVE_PLATFORM_IPHONE_OS
2972                     // don't actually go to sleep, if H4 supports power management
2973                     if (btstack_control_iphone_power_management_enabled()){
2974                         // SLEEP MODE reached
2975                         hci_stack->state = HCI_STATE_SLEEPING;
2976                         hci_emit_state();
2977                         break;
2978                     }
2979 #endif
2980                     // switch mode
2981                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
2982                     hci_emit_state();
2983                     break;
2984 
2985                 default:
2986                     break;
2987             }
2988             break;
2989 
2990         default:
2991             break;
2992     }
2993 }
2994 
2995 int hci_send_cmd_packet(uint8_t *packet, int size){
2996     // house-keeping
2997 
2998     if (IS_COMMAND(packet, hci_write_loopback_mode)){
2999         hci_stack->loopback_mode = packet[3];
3000     }
3001 
3002 #ifdef ENABLE_CLASSIC
3003     bd_addr_t addr;
3004     hci_connection_t * conn;
3005 
3006     // create_connection?
3007     if (IS_COMMAND(packet, hci_create_connection)){
3008         reverse_bd_addr(&packet[3], addr);
3009         log_info("Create_connection to %s", bd_addr_to_str(addr));
3010 
3011         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
3012         if (!conn){
3013             conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
3014             if (!conn){
3015                 // notify client that alloc failed
3016                 hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
3017                 return 0; // don't sent packet to controller
3018             }
3019             conn->state = SEND_CREATE_CONNECTION;
3020         }
3021         log_info("conn state %u", conn->state);
3022         switch (conn->state){
3023             // if connection active exists
3024             case OPEN:
3025                 // and OPEN, emit connection complete command, don't send to controller
3026                 hci_emit_connection_complete(addr, conn->con_handle, 0);
3027                 return 0;
3028             case SEND_CREATE_CONNECTION:
3029                 // connection created by hci, e.g. dedicated bonding
3030                 break;
3031             default:
3032                 // otherwise, just ignore as it is already in the open process
3033                 return 0;
3034         }
3035         conn->state = SENT_CREATE_CONNECTION;
3036     }
3037 
3038     if (IS_COMMAND(packet, hci_link_key_request_reply)){
3039         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
3040     }
3041     if (IS_COMMAND(packet, hci_link_key_request_negative_reply)){
3042         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
3043     }
3044 
3045     if (IS_COMMAND(packet, hci_delete_stored_link_key)){
3046         if (hci_stack->link_key_db){
3047             reverse_bd_addr(&packet[3], addr);
3048             hci_stack->link_key_db->delete_link_key(addr);
3049         }
3050     }
3051 
3052     if (IS_COMMAND(packet, hci_pin_code_request_negative_reply)
3053     ||  IS_COMMAND(packet, hci_pin_code_request_reply)){
3054         reverse_bd_addr(&packet[3], addr);
3055         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
3056         if (conn){
3057             connectionClearAuthenticationFlags(conn, LEGACY_PAIRING_ACTIVE);
3058         }
3059     }
3060 
3061     if (IS_COMMAND(packet, hci_user_confirmation_request_negative_reply)
3062     ||  IS_COMMAND(packet, hci_user_confirmation_request_reply)
3063     ||  IS_COMMAND(packet, hci_user_passkey_request_negative_reply)
3064     ||  IS_COMMAND(packet, hci_user_passkey_request_reply)) {
3065         reverse_bd_addr(&packet[3], addr);
3066         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
3067         if (conn){
3068             connectionClearAuthenticationFlags(conn, SSP_PAIRING_ACTIVE);
3069         }
3070     }
3071 #endif
3072 
3073 #ifdef ENABLE_BLE
3074 #ifdef ENABLE_LE_PERIPHERAL
3075     if (IS_COMMAND(packet, hci_le_set_random_address)){
3076         hci_stack->le_random_address_set = 1;
3077         reverse_bd_addr(&packet[3], hci_stack->le_random_address);
3078     }
3079     if (IS_COMMAND(packet, hci_le_set_advertise_enable)){
3080         hci_stack->le_advertisements_active = packet[3];
3081     }
3082 #endif
3083 #ifdef ENABLE_LE_CENTRAL
3084     if (IS_COMMAND(packet, hci_le_create_connection)){
3085         // white list used?
3086         uint8_t initiator_filter_policy = packet[7];
3087         switch (initiator_filter_policy){
3088             case 0:
3089                 // whitelist not used
3090                 hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
3091                 break;
3092             case 1:
3093                 hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
3094                 break;
3095             default:
3096                 log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
3097                 break;
3098         }
3099     }
3100     if (IS_COMMAND(packet, hci_le_create_connection_cancel)){
3101         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
3102     }
3103 #endif
3104 #endif
3105 
3106     hci_stack->num_cmd_packets--;
3107 
3108     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
3109     int err = hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
3110 
3111     // release packet buffer for synchronous transport implementations
3112     if (hci_transport_synchronous() && (packet == hci_stack->hci_packet_buffer)){
3113         hci_stack->hci_packet_buffer_reserved = 0;
3114     }
3115 
3116     return err;
3117 }
3118 
3119 // disconnect because of security block
3120 void hci_disconnect_security_block(hci_con_handle_t con_handle){
3121     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3122     if (!connection) return;
3123     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
3124 }
3125 
3126 
3127 // Configure Secure Simple Pairing
3128 
3129 #ifdef ENABLE_CLASSIC
3130 
3131 // enable will enable SSP during init
3132 void gap_ssp_set_enable(int enable){
3133     hci_stack->ssp_enable = enable;
3134 }
3135 
3136 static int hci_local_ssp_activated(void){
3137     return gap_ssp_supported() && hci_stack->ssp_enable;
3138 }
3139 
3140 // if set, BTstack will respond to io capability request using authentication requirement
3141 void gap_ssp_set_io_capability(int io_capability){
3142     hci_stack->ssp_io_capability = io_capability;
3143 }
3144 void gap_ssp_set_authentication_requirement(int authentication_requirement){
3145     hci_stack->ssp_authentication_requirement = authentication_requirement;
3146 }
3147 
3148 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
3149 void gap_ssp_set_auto_accept(int auto_accept){
3150     hci_stack->ssp_auto_accept = auto_accept;
3151 }
3152 #endif
3153 
3154 // va_list part of hci_send_cmd
3155 int hci_send_cmd_va_arg(const hci_cmd_t *cmd, va_list argptr){
3156     if (!hci_can_send_command_packet_now()){
3157         log_error("hci_send_cmd called but cannot send packet now");
3158         return 0;
3159     }
3160 
3161     // for HCI INITIALIZATION
3162     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
3163     hci_stack->last_cmd_opcode = cmd->opcode;
3164 
3165     hci_reserve_packet_buffer();
3166     uint8_t * packet = hci_stack->hci_packet_buffer;
3167     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
3168     return hci_send_cmd_packet(packet, size);
3169 }
3170 
3171 /**
3172  * pre: numcmds >= 0 - it's allowed to send a command to the controller
3173  */
3174 int hci_send_cmd(const hci_cmd_t *cmd, ...){
3175     va_list argptr;
3176     va_start(argptr, cmd);
3177     int res = hci_send_cmd_va_arg(cmd, argptr);
3178     va_end(argptr);
3179     return res;
3180 }
3181 
3182 // Create various non-HCI events.
3183 // TODO: generalize, use table similar to hci_create_command
3184 
3185 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
3186     // dump packet
3187     if (dump) {
3188         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
3189     }
3190 
3191     // dispatch to all event handlers
3192     btstack_linked_list_iterator_t it;
3193     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
3194     while (btstack_linked_list_iterator_has_next(&it)){
3195         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
3196         entry->callback(HCI_EVENT_PACKET, 0, event, size);
3197     }
3198 }
3199 
3200 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
3201     if (!hci_stack->acl_packet_handler) return;
3202     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
3203 }
3204 
3205 #ifdef ENABLE_CLASSIC
3206 static void hci_notify_if_sco_can_send_now(void){
3207     // notify SCO sender if waiting
3208     if (!hci_stack->sco_waiting_for_can_send_now) return;
3209     if (hci_can_send_sco_packet_now()){
3210         hci_stack->sco_waiting_for_can_send_now = 0;
3211         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
3212         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
3213         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
3214     }
3215 }
3216 #endif
3217 
3218 void hci_emit_state(void){
3219     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
3220     uint8_t event[3];
3221     event[0] = BTSTACK_EVENT_STATE;
3222     event[1] = sizeof(event) - 2;
3223     event[2] = hci_stack->state;
3224     hci_emit_event(event, sizeof(event), 1);
3225 }
3226 
3227 #ifdef ENABLE_CLASSIC
3228 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
3229     uint8_t event[13];
3230     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
3231     event[1] = sizeof(event) - 2;
3232     event[2] = status;
3233     little_endian_store_16(event, 3, con_handle);
3234     reverse_bd_addr(address, &event[5]);
3235     event[11] = 1; // ACL connection
3236     event[12] = 0; // encryption disabled
3237     hci_emit_event(event, sizeof(event), 1);
3238 }
3239 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
3240     if (disable_l2cap_timeouts) return;
3241     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
3242     uint8_t event[4];
3243     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
3244     event[1] = sizeof(event) - 2;
3245     little_endian_store_16(event, 2, conn->con_handle);
3246     hci_emit_event(event, sizeof(event), 1);
3247 }
3248 #endif
3249 
3250 #ifdef ENABLE_BLE
3251 #ifdef ENABLE_LE_CENTRAL
3252 static void hci_emit_le_connection_complete(uint8_t address_type, bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
3253     uint8_t event[21];
3254     event[0] = HCI_EVENT_LE_META;
3255     event[1] = sizeof(event) - 2;
3256     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
3257     event[3] = status;
3258     little_endian_store_16(event, 4, con_handle);
3259     event[6] = 0; // TODO: role
3260     event[7] = address_type;
3261     reverse_bd_addr(address, &event[8]);
3262     little_endian_store_16(event, 14, 0); // interval
3263     little_endian_store_16(event, 16, 0); // latency
3264     little_endian_store_16(event, 18, 0); // supervision timeout
3265     event[20] = 0; // master clock accuracy
3266     hci_emit_event(event, sizeof(event), 1);
3267 }
3268 #endif
3269 #endif
3270 
3271 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
3272     uint8_t event[6];
3273     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
3274     event[1] = sizeof(event) - 2;
3275     event[2] = 0; // status = OK
3276     little_endian_store_16(event, 3, con_handle);
3277     event[5] = reason;
3278     hci_emit_event(event, sizeof(event), 1);
3279 }
3280 
3281 static void hci_emit_nr_connections_changed(void){
3282     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
3283     uint8_t event[3];
3284     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
3285     event[1] = sizeof(event) - 2;
3286     event[2] = nr_hci_connections();
3287     hci_emit_event(event, sizeof(event), 1);
3288 }
3289 
3290 static void hci_emit_hci_open_failed(void){
3291     log_info("BTSTACK_EVENT_POWERON_FAILED");
3292     uint8_t event[2];
3293     event[0] = BTSTACK_EVENT_POWERON_FAILED;
3294     event[1] = sizeof(event) - 2;
3295     hci_emit_event(event, sizeof(event), 1);
3296 }
3297 
3298 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
3299     log_info("hci_emit_dedicated_bonding_result %u ", status);
3300     uint8_t event[9];
3301     int pos = 0;
3302     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
3303     event[pos++] = sizeof(event) - 2;
3304     event[pos++] = status;
3305     reverse_bd_addr(address, &event[pos]);
3306     hci_emit_event(event, sizeof(event), 1);
3307 }
3308 
3309 
3310 #ifdef ENABLE_CLASSIC
3311 
3312 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
3313     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
3314     uint8_t event[5];
3315     int pos = 0;
3316     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
3317     event[pos++] = sizeof(event) - 2;
3318     little_endian_store_16(event, 2, con_handle);
3319     pos += 2;
3320     event[pos++] = level;
3321     hci_emit_event(event, sizeof(event), 1);
3322 }
3323 
3324 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
3325     if (!connection) return LEVEL_0;
3326     if ((connection->authentication_flags & CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
3327     return gap_security_level_for_link_key_type(connection->link_key_type);
3328 }
3329 
3330 static void hci_emit_discoverable_enabled(uint8_t enabled){
3331     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
3332     uint8_t event[3];
3333     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
3334     event[1] = sizeof(event) - 2;
3335     event[2] = enabled;
3336     hci_emit_event(event, sizeof(event), 1);
3337 }
3338 
3339 #ifdef ENABLE_CLASSIC
3340 // query if remote side supports eSCO
3341 int hci_remote_esco_supported(hci_con_handle_t con_handle){
3342     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3343     if (!connection) return 0;
3344     return connection->remote_supported_feature_eSCO;
3345 }
3346 
3347 // query if remote side supports SSP
3348 int hci_remote_ssp_supported(hci_con_handle_t con_handle){
3349     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3350     if (!connection) return 0;
3351     return (connection->bonding_flags & BONDING_REMOTE_SUPPORTS_SSP) ? 1 : 0;
3352 }
3353 
3354 int gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
3355     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
3356 }
3357 #endif
3358 
3359 // GAP API
3360 /**
3361  * @bbrief enable/disable bonding. default is enabled
3362  * @praram enabled
3363  */
3364 void gap_set_bondable_mode(int enable){
3365     hci_stack->bondable = enable ? 1 : 0;
3366 }
3367 /**
3368  * @brief Get bondable mode.
3369  * @return 1 if bondable
3370  */
3371 int gap_get_bondable_mode(void){
3372     return hci_stack->bondable;
3373 }
3374 
3375 /**
3376  * @brief map link keys to security levels
3377  */
3378 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
3379     switch (link_key_type){
3380         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
3381             return LEVEL_4;
3382         case COMBINATION_KEY:
3383         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
3384             return LEVEL_3;
3385         default:
3386             return LEVEL_2;
3387     }
3388 }
3389 
3390 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
3391     log_info("gap_mitm_protection_required_for_security_level %u", level);
3392     return level > LEVEL_2;
3393 }
3394 
3395 /**
3396  * @brief get current security level
3397  */
3398 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
3399     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3400     if (!connection) return LEVEL_0;
3401     return gap_security_level_for_connection(connection);
3402 }
3403 
3404 /**
3405  * @brief request connection to device to
3406  * @result GAP_AUTHENTICATION_RESULT
3407  */
3408 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
3409     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3410     if (!connection){
3411         hci_emit_security_level(con_handle, LEVEL_0);
3412         return;
3413     }
3414     gap_security_level_t current_level = gap_security_level(con_handle);
3415     log_info("gap_request_security_level %u, current level %u", requested_level, current_level);
3416     if (current_level >= requested_level){
3417         hci_emit_security_level(con_handle, current_level);
3418         return;
3419     }
3420 
3421     connection->requested_security_level = requested_level;
3422 
3423 #if 0
3424     // sending encryption request without a link key results in an error.
3425     // TODO: figure out how to use it properly
3426 
3427     // would enabling ecnryption suffice (>= LEVEL_2)?
3428     if (hci_stack->link_key_db){
3429         link_key_type_t link_key_type;
3430         link_key_t      link_key;
3431         if (hci_stack->link_key_db->get_link_key( &connection->address, &link_key, &link_key_type)){
3432             if (gap_security_level_for_link_key_type(link_key_type) >= requested_level){
3433                 connection->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
3434                 return;
3435             }
3436         }
3437     }
3438 #endif
3439 
3440     // try to authenticate connection
3441     connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
3442     hci_run();
3443 }
3444 
3445 /**
3446  * @brief start dedicated bonding with device. disconnect after bonding
3447  * @param device
3448  * @param request MITM protection
3449  * @result GAP_DEDICATED_BONDING_COMPLETE
3450  */
3451 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
3452 
3453     // create connection state machine
3454     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_CLASSIC);
3455 
3456     if (!connection){
3457         return BTSTACK_MEMORY_ALLOC_FAILED;
3458     }
3459 
3460     // delete linkn key
3461     gap_drop_link_key_for_bd_addr(device);
3462 
3463     // configure LEVEL_2/3, dedicated bonding
3464     connection->state = SEND_CREATE_CONNECTION;
3465     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
3466     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
3467     connection->bonding_flags = BONDING_DEDICATED;
3468 
3469     // wait for GAP Security Result and send GAP Dedicated Bonding complete
3470 
3471     // handle: connnection failure (connection complete != ok)
3472     // handle: authentication failure
3473     // handle: disconnect on done
3474 
3475     hci_run();
3476 
3477     return 0;
3478 }
3479 #endif
3480 
3481 void gap_set_local_name(const char * local_name){
3482     hci_stack->local_name = local_name;
3483 }
3484 
3485 
3486 #ifdef ENABLE_BLE
3487 
3488 #ifdef ENABLE_LE_CENTRAL
3489 void gap_start_scan(void){
3490     if (hci_stack->le_scanning_state == LE_SCANNING) return;
3491     hci_stack->le_scanning_state = LE_START_SCAN;
3492     hci_run();
3493 }
3494 
3495 void gap_stop_scan(void){
3496     if ( hci_stack->le_scanning_state == LE_SCAN_IDLE) return;
3497     hci_stack->le_scanning_state = LE_STOP_SCAN;
3498     hci_run();
3499 }
3500 
3501 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
3502     hci_stack->le_scan_type     = scan_type;
3503     hci_stack->le_scan_interval = scan_interval;
3504     hci_stack->le_scan_window   = scan_window;
3505     hci_run();
3506 }
3507 
3508 uint8_t gap_connect(bd_addr_t addr, bd_addr_type_t addr_type){
3509     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
3510     if (!conn){
3511         log_info("gap_connect: no connection exists yet, creating context");
3512         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
3513         if (!conn){
3514             // notify client that alloc failed
3515             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
3516             log_info("gap_connect: failed to alloc hci_connection_t");
3517             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
3518         }
3519         conn->state = SEND_CREATE_CONNECTION;
3520         log_info("gap_connect: send create connection next");
3521         hci_run();
3522         return 0;
3523     }
3524 
3525     if (!hci_is_le_connection(conn) ||
3526         conn->state == SEND_CREATE_CONNECTION ||
3527         conn->state == SENT_CREATE_CONNECTION) {
3528         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
3529         log_error("gap_connect: classic connection or connect is already being created");
3530         return GATT_CLIENT_IN_WRONG_STATE;
3531     }
3532 
3533     log_info("gap_connect: context exists with state %u", conn->state);
3534     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, 0);
3535     hci_run();
3536     return 0;
3537 }
3538 
3539 // @assumption: only a single outgoing LE Connection exists
3540 static hci_connection_t * gap_get_outgoing_connection(void){
3541     btstack_linked_item_t *it;
3542     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
3543         hci_connection_t * conn = (hci_connection_t *) it;
3544         if (!hci_is_le_connection(conn)) continue;
3545         switch (conn->state){
3546             case SEND_CREATE_CONNECTION:
3547             case SENT_CREATE_CONNECTION:
3548                 return conn;
3549             default:
3550                 break;
3551         };
3552     }
3553     return NULL;
3554 }
3555 
3556 uint8_t gap_connect_cancel(void){
3557     hci_connection_t * conn = gap_get_outgoing_connection();
3558     if (!conn) return 0;
3559     switch (conn->state){
3560         case SEND_CREATE_CONNECTION:
3561             // skip sending create connection and emit event instead
3562             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
3563             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
3564             btstack_memory_hci_connection_free( conn );
3565             break;
3566         case SENT_CREATE_CONNECTION:
3567             // request to send cancel connection
3568             conn->state = SEND_CANCEL_CONNECTION;
3569             hci_run();
3570             break;
3571         default:
3572             break;
3573     }
3574     return 0;
3575 }
3576 #endif
3577 
3578 /**
3579  * @brief Updates the connection parameters for a given LE connection
3580  * @param handle
3581  * @param conn_interval_min (unit: 1.25ms)
3582  * @param conn_interval_max (unit: 1.25ms)
3583  * @param conn_latency
3584  * @param supervision_timeout (unit: 10ms)
3585  * @returns 0 if ok
3586  */
3587 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
3588     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
3589     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3590     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3591     connection->le_conn_interval_min = conn_interval_min;
3592     connection->le_conn_interval_max = conn_interval_max;
3593     connection->le_conn_latency = conn_latency;
3594     connection->le_supervision_timeout = supervision_timeout;
3595     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
3596     hci_run();
3597     return 0;
3598 }
3599 
3600 /**
3601  * @brief Request an update of the connection parameter for a given LE connection
3602  * @param handle
3603  * @param conn_interval_min (unit: 1.25ms)
3604  * @param conn_interval_max (unit: 1.25ms)
3605  * @param conn_latency
3606  * @param supervision_timeout (unit: 10ms)
3607  * @returns 0 if ok
3608  */
3609 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
3610     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
3611     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3612     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3613     connection->le_conn_interval_min = conn_interval_min;
3614     connection->le_conn_interval_max = conn_interval_max;
3615     connection->le_conn_latency = conn_latency;
3616     connection->le_supervision_timeout = supervision_timeout;
3617     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
3618     hci_run();
3619     return 0;
3620 }
3621 
3622 #ifdef ENABLE_LE_PERIPHERAL
3623 
3624 static void gap_advertisments_changed(void){
3625     // disable advertisements before updating adv, scan data, or adv params
3626     if (hci_stack->le_advertisements_active){
3627         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE | LE_ADVERTISEMENT_TASKS_ENABLE;
3628     }
3629     hci_run();
3630 }
3631 
3632 /**
3633  * @brief Set Advertisement Data
3634  * @param advertising_data_length
3635  * @param advertising_data (max 31 octets)
3636  * @note data is not copied, pointer has to stay valid
3637  */
3638 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
3639     hci_stack->le_advertisements_data_len = advertising_data_length;
3640     hci_stack->le_advertisements_data = advertising_data;
3641     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3642     gap_advertisments_changed();
3643 }
3644 
3645 /**
3646  * @brief Set Scan Response Data
3647  * @param advertising_data_length
3648  * @param advertising_data (max 31 octets)
3649  * @note data is not copied, pointer has to stay valid
3650  */
3651 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
3652     hci_stack->le_scan_response_data_len = scan_response_data_length;
3653     hci_stack->le_scan_response_data = scan_response_data;
3654     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
3655     gap_advertisments_changed();
3656 }
3657 
3658 /**
3659  * @brief Set Advertisement Parameters
3660  * @param adv_int_min
3661  * @param adv_int_max
3662  * @param adv_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 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_direct_address_type = direct_address_typ;
3678     hci_stack->le_advertisements_channel_map = channel_map;
3679     hci_stack->le_advertisements_filter_policy = filter_policy;
3680     memcpy(hci_stack->le_advertisements_direct_address, direct_address, 6);
3681 
3682     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3683     gap_advertisments_changed();
3684  }
3685 
3686 void hci_le_set_own_address_type(uint8_t own_address_type){
3687     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
3688     if (own_address_type == hci_stack->le_own_addr_type) return;
3689     hci_stack->le_own_addr_type = own_address_type;
3690 
3691     // update advertisement parameters, too
3692     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3693     gap_advertisments_changed();
3694     // note: we don't update scan parameters or modify ongoing connection attempts
3695 }
3696 
3697 /**
3698  * @brief Enable/Disable Advertisements
3699  * @param enabled
3700  */
3701 void gap_advertisements_enable(int enabled){
3702     hci_stack->le_advertisements_enabled = enabled;
3703     if (enabled && !hci_stack->le_advertisements_active){
3704         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
3705     }
3706     if (!enabled && hci_stack->le_advertisements_active){
3707         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE;
3708     }
3709     hci_run();
3710 }
3711 
3712 #endif
3713 #endif
3714 
3715 uint8_t gap_disconnect(hci_con_handle_t handle){
3716     hci_connection_t * conn = hci_connection_for_handle(handle);
3717     if (!conn){
3718         hci_emit_disconnection_complete(handle, 0);
3719         return 0;
3720     }
3721     conn->state = SEND_DISCONNECT;
3722     hci_run();
3723     return 0;
3724 }
3725 
3726 /**
3727  * @brief Get connection type
3728  * @param con_handle
3729  * @result connection_type
3730  */
3731 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
3732     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
3733     if (!conn) return GAP_CONNECTION_INVALID;
3734     switch (conn->address_type){
3735         case BD_ADDR_TYPE_LE_PUBLIC:
3736         case BD_ADDR_TYPE_LE_RANDOM:
3737             return GAP_CONNECTION_LE;
3738         case BD_ADDR_TYPE_SCO:
3739             return GAP_CONNECTION_SCO;
3740         case BD_ADDR_TYPE_CLASSIC:
3741             return GAP_CONNECTION_ACL;
3742         default:
3743             return GAP_CONNECTION_INVALID;
3744     }
3745 }
3746 
3747 #ifdef ENABLE_BLE
3748 
3749 #ifdef ENABLE_LE_CENTRAL
3750 /**
3751  * @brief Auto Connection Establishment - Start Connecting to device
3752  * @param address_typ
3753  * @param address
3754  * @returns 0 if ok
3755  */
3756 int gap_auto_connection_start(bd_addr_type_t address_type, bd_addr_t address){
3757     // check capacity
3758     int num_entries = btstack_linked_list_count(&hci_stack->le_whitelist);
3759     if (num_entries >= hci_stack->le_whitelist_capacity) return ERROR_CODE_MEMORY_CAPACITY_EXCEEDED;
3760     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
3761     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
3762     entry->address_type = address_type;
3763     memcpy(entry->address, address, 6);
3764     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
3765     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
3766     hci_run();
3767     return 0;
3768 }
3769 
3770 static void hci_remove_from_whitelist(bd_addr_type_t address_type, bd_addr_t address){
3771     btstack_linked_list_iterator_t it;
3772     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
3773     while (btstack_linked_list_iterator_has_next(&it)){
3774         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
3775         if (entry->address_type != address_type) continue;
3776         if (memcmp(entry->address, address, 6) != 0) continue;
3777         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
3778             // remove from controller if already present
3779             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
3780             continue;
3781         }
3782         // direclty remove entry from whitelist
3783         btstack_linked_list_iterator_remove(&it);
3784         btstack_memory_whitelist_entry_free(entry);
3785     }
3786 }
3787 
3788 /**
3789  * @brief Auto Connection Establishment - Stop Connecting to device
3790  * @param address_typ
3791  * @param address
3792  * @returns 0 if ok
3793  */
3794 int gap_auto_connection_stop(bd_addr_type_t address_type, bd_addr_t address){
3795     hci_remove_from_whitelist(address_type, address);
3796     hci_run();
3797     return 0;
3798 }
3799 
3800 /**
3801  * @brief Auto Connection Establishment - Stop everything
3802  * @note  Convenience function to stop all active auto connection attempts
3803  */
3804 void gap_auto_connection_stop_all(void){
3805     btstack_linked_list_iterator_t it;
3806     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
3807     while (btstack_linked_list_iterator_has_next(&it)){
3808         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
3809         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
3810             // remove from controller if already present
3811             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
3812             continue;
3813         }
3814         // directly remove entry from whitelist
3815         btstack_linked_list_iterator_remove(&it);
3816         btstack_memory_whitelist_entry_free(entry);
3817     }
3818     hci_run();
3819 }
3820 #endif
3821 #endif
3822 
3823 #ifdef ENABLE_CLASSIC
3824 /**
3825  * @brief Set Extended Inquiry Response data
3826  * @param eir_data size 240 bytes, is not copied make sure memory is accessible during stack startup
3827  * @note has to be done before stack starts up
3828  */
3829 void gap_set_extended_inquiry_response(const uint8_t * data){
3830     hci_stack->eir_data = data;
3831 }
3832 
3833 /**
3834  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
3835  * @param inquriy_mode see bluetooth_defines.h
3836  */
3837 void hci_set_inquiry_mode(inquiry_mode_t mode){
3838     hci_stack->inquiry_mode = mode;
3839 }
3840 
3841 /**
3842  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
3843  */
3844 void hci_set_sco_voice_setting(uint16_t voice_setting){
3845     hci_stack->sco_voice_setting = voice_setting;
3846 }
3847 
3848 /**
3849  * @brief Get SCO Voice Setting
3850  * @return current voice setting
3851  */
3852 uint16_t hci_get_sco_voice_setting(void){
3853     return hci_stack->sco_voice_setting;
3854 }
3855 
3856 /** @brief Get SCO packet length for current SCO Voice setting
3857  *  @note  Using SCO packets of the exact length is required for USB transfer
3858  *  @return Length of SCO packets in bytes (not audio frames)
3859  */
3860 int hci_get_sco_packet_length(void){
3861     // see Core Spec for H2 USB Transfer.
3862     if (hci_stack->sco_voice_setting & 0x0020) return 51;
3863     return 27;
3864 }
3865 #endif
3866 
3867 /**
3868  * @brief Set callback for Bluetooth Hardware Error
3869  */
3870 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
3871     hci_stack->hardware_error_callback = fn;
3872 }
3873 
3874 void hci_disconnect_all(void){
3875     btstack_linked_list_iterator_t it;
3876     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
3877     while (btstack_linked_list_iterator_has_next(&it)){
3878         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
3879         if (con->state == SENT_DISCONNECT) continue;
3880         con->state = SEND_DISCONNECT;
3881     }
3882     hci_run();
3883 }
3884 
3885 uint16_t hci_get_manufacturer(void){
3886     return hci_stack->manufacturer;
3887 }
3888