xref: /btstack/src/classic/avrcp.c (revision 94d9400d03d0b01a8edb1fd9164531e968621d16)
1 /*
2  * Copyright (C) 2016 BlueKitchen GmbH
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the copyright holders nor the names of
14  *    contributors may be used to endorse or promote products derived
15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
17  *    personal benefit and not for any commercial purpose or for
18  *    monetary gain.
19  *
20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
24  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 #define __BTSTACK_FILE__ "avrcp.c"
39 
40 #include <stdint.h>
41 #include <stdio.h>
42 #include <stdlib.h>
43 #include <string.h>
44 
45 #include "btstack.h"
46 #include "classic/avrcp.h"
47 #include "classic/avrcp_controller.h"
48 
49 #define PSM_AVCTP                       BLUETOOTH_PROTOCOL_AVCTP
50 #define PSM_AVCTP_BROWSING              0x001b
51 
52 static const char * default_avrcp_controller_service_name = "BTstack AVRCP Controller Service";
53 static const char * default_avrcp_controller_service_provider_name = "BTstack AVRCP Controller Service Provider";
54 static const char * default_avrcp_target_service_name = "BTstack AVRCP Target Service";
55 static const char * default_avrcp_target_service_provider_name = "BTstack AVRCP Target Service Provider";
56 
57 static uint16_t  avrcp_cid_counter = 0;
58 
59 static avrcp_context_t * sdp_query_context;
60 static uint8_t   attribute_value[1000];
61 static const unsigned int attribute_value_buffer_size = sizeof(attribute_value);
62 
63 static btstack_linked_list_t connections;
64 
65 static const char * avrcp_subunit_type_name[] = {
66     "MONITOR", "AUDIO", "PRINTER", "DISC", "TAPE_RECORDER_PLAYER", "TUNER",
67     "CA", "CAMERA", "RESERVED", "PANEL", "BULLETIN_BOARD", "CAMERA_STORAGE",
68     "VENDOR_UNIQUE", "RESERVED_FOR_ALL_SUBUNIT_TYPES",
69     "EXTENDED_TO_NEXT_BYTE", "UNIT", "ERROR"
70 };
71 
72 const char * avrcp_subunit2str(uint16_t index){
73     if (index <= 11) return avrcp_subunit_type_name[index];
74     if (index >= 0x1C && index <= 0x1F) return avrcp_subunit_type_name[index - 0x10];
75     return avrcp_subunit_type_name[16];
76 }
77 
78 static const char * avrcp_event_name[] = {
79     "ERROR", "PLAYBACK_STATUS_CHANGED",
80     "TRACK_CHANGED", "TRACK_REACHED_END", "TRACK_REACHED_START",
81     "PLAYBACK_POS_CHANGED", "BATT_STATUS_CHANGED", "SYSTEM_STATUS_CHANGED",
82     "PLAYER_APPLICATION_SETTING_CHANGED", "NOW_PLAYING_CONTENT_CHANGED",
83     "AVAILABLE_PLAYERS_CHANGED", "ADDRESSED_PLAYER_CHANGED", "UIDS_CHANGED", "VOLUME_CHANGED"
84 };
85 const char * avrcp_event2str(uint16_t index){
86     if (index <= 0x0d) return avrcp_event_name[index];
87     return avrcp_event_name[0];
88 }
89 
90 static const char * avrcp_operation_name[] = {
91     "NOT SUPPORTED", // 0x3B
92     "SKIP", "NOT SUPPORTED", "NOT SUPPORTED", "NOT SUPPORTED", "NOT SUPPORTED",
93     "VOLUME_UP", "VOLUME_DOWN", "MUTE", "PLAY", "STOP", "PAUSE", "NOT SUPPORTED",
94     "REWIND", "FAST_FORWARD", "NOT SUPPORTED", "FORWARD", "BACKWARD" // 0x4C
95 };
96 const char * avrcp_operation2str(uint8_t index){
97     if (index >= 0x3B && index <= 0x4C) return avrcp_operation_name[index - 0x3B];
98     return avrcp_operation_name[0];
99 }
100 
101 static const char * avrcp_media_attribute_id_name[] = {
102     "NONE", "TITLE", "ARTIST", "ALBUM", "TRACK", "TOTAL TRACKS", "GENRE", "SONG LENGTH"
103 };
104 const char * avrcp_attribute2str(uint8_t index){
105     if (index >= 1 && index <= 7) return avrcp_media_attribute_id_name[index];
106     return avrcp_media_attribute_id_name[0];
107 }
108 
109 static const char * avrcp_play_status_name[] = {
110     "STOPPED", "PLAYING", "PAUSED", "FORWARD SEEK", "REVERSE SEEK",
111     "ERROR" // 0xFF
112 };
113 const char * avrcp_play_status2str(uint8_t index){
114     if (index >= 1 && index <= 4) return avrcp_play_status_name[index];
115     return avrcp_play_status_name[5];
116 }
117 
118 static const char * avrcp_ctype_name[] = {
119     "CONTROL",
120     "STATUS",
121     "SPECIFIC_INQUIRY",
122     "NOTIFY",
123     "GENERAL_INQUIRY",
124     "RESERVED5",
125     "RESERVED6",
126     "RESERVED7",
127     "NOT IMPLEMENTED IN REMOTE",
128     "ACCEPTED BY REMOTE",
129     "REJECTED BY REMOTE",
130     "IN_TRANSITION",
131     "IMPLEMENTED_STABLE",
132     "CHANGED_STABLE",
133     "RESERVED",
134     "INTERIM"
135 };
136 const char * avrcp_ctype2str(uint8_t index){
137     if (index < sizeof(avrcp_ctype_name)){
138         return avrcp_ctype_name[index];
139     }
140     return "NONE";
141 }
142 
143 static const char * avrcp_shuffle_mode_name[] = {
144     "SHUFFLE OFF",
145     "SHUFFLE ALL TRACKS",
146     "SHUFFLE GROUP"
147 };
148 
149 const char * avrcp_shuffle2str(uint8_t index){
150     if (index >= 1 && index <= 3) return avrcp_shuffle_mode_name[index-1];
151     return "NONE";
152 }
153 
154 static const char * avrcp_repeat_mode_name[] = {
155     "REPEAT OFF",
156     "REPEAT SINGLE TRACK",
157     "REPEAT ALL TRACKS",
158     "REPEAT GROUP"
159 };
160 
161 const char * avrcp_repeat2str(uint8_t index){
162     if (index >= 1 && index <= 4) return avrcp_repeat_mode_name[index-1];
163     return "NONE";
164 }
165 
166 uint8_t avrcp_cmd_opcode(uint8_t *packet, uint16_t size){
167     uint8_t cmd_opcode_index = 5;
168     if (cmd_opcode_index > size) return AVRCP_CMD_OPCODE_UNDEFINED;
169     return packet[cmd_opcode_index];
170 }
171 
172 void avrcp_create_sdp_record(uint8_t controller, uint8_t * service, uint32_t service_record_handle, uint8_t browsing, uint16_t supported_features,
173     const char * service_name, const char * service_provider_name){
174     uint8_t* attribute;
175     de_create_sequence(service);
176 
177     // 0x0000 "Service Record Handle"
178     de_add_number(service, DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_SERVICE_RECORD_HANDLE);
179     de_add_number(service, DE_UINT, DE_SIZE_32, service_record_handle);
180 
181     // 0x0001 "Service Class ID List"
182     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_SERVICE_CLASS_ID_LIST);
183     attribute = de_push_sequence(service);
184     {
185         if (controller){
186             de_add_number(attribute, DE_UUID, DE_SIZE_16, BLUETOOTH_SERVICE_CLASS_AV_REMOTE_CONTROL);
187             de_add_number(attribute, DE_UUID, DE_SIZE_16, BLUETOOTH_SERVICE_CLASS_AV_REMOTE_CONTROL_CONTROLLER);
188         } else {
189             de_add_number(attribute, DE_UUID, DE_SIZE_16, BLUETOOTH_SERVICE_CLASS_AV_REMOTE_CONTROL_TARGET);
190         }
191     }
192     de_pop_sequence(service, attribute);
193 
194     // 0x0004 "Protocol Descriptor List"
195     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_PROTOCOL_DESCRIPTOR_LIST);
196     attribute = de_push_sequence(service);
197     {
198         uint8_t* l2cpProtocol = de_push_sequence(attribute);
199         {
200             de_add_number(l2cpProtocol,  DE_UUID, DE_SIZE_16, BLUETOOTH_PROTOCOL_L2CAP);
201             de_add_number(l2cpProtocol,  DE_UINT, DE_SIZE_16, BLUETOOTH_PROTOCOL_AVCTP);
202         }
203         de_pop_sequence(attribute, l2cpProtocol);
204 
205         uint8_t* avctpProtocol = de_push_sequence(attribute);
206         {
207             de_add_number(avctpProtocol,  DE_UUID, DE_SIZE_16, BLUETOOTH_PROTOCOL_AVCTP);  // avctpProtocol_service
208             de_add_number(avctpProtocol,  DE_UINT, DE_SIZE_16,  0x0103);    // version
209         }
210         de_pop_sequence(attribute, avctpProtocol);
211     }
212     de_pop_sequence(service, attribute);
213 
214     // 0x0005 "Public Browse Group"
215     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_BROWSE_GROUP_LIST); // public browse group
216     attribute = de_push_sequence(service);
217     {
218         de_add_number(attribute,  DE_UUID, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_PUBLIC_BROWSE_ROOT);
219     }
220     de_pop_sequence(service, attribute);
221 
222     // 0x0009 "Bluetooth Profile Descriptor List"
223     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_BLUETOOTH_PROFILE_DESCRIPTOR_LIST);
224     attribute = de_push_sequence(service);
225     {
226         uint8_t *avrcProfile = de_push_sequence(attribute);
227         {
228             de_add_number(avrcProfile,  DE_UUID, DE_SIZE_16, BLUETOOTH_SERVICE_CLASS_AV_REMOTE_CONTROL);
229             de_add_number(avrcProfile,  DE_UINT, DE_SIZE_16, 0x0105);
230         }
231         de_pop_sequence(attribute, avrcProfile);
232     }
233     de_pop_sequence(service, attribute);
234 
235     // 0x000d "Additional Bluetooth Profile Descriptor List"
236     if (browsing){
237         de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_ADDITIONAL_PROTOCOL_DESCRIPTOR_LISTS);
238         attribute = de_push_sequence(service);
239         {
240             uint8_t * des = de_push_sequence(attribute);
241             {
242                 uint8_t* browsing_l2cpProtocol = de_push_sequence(des);
243                 {
244                     de_add_number(browsing_l2cpProtocol,  DE_UUID, DE_SIZE_16, BLUETOOTH_PROTOCOL_L2CAP);
245                     de_add_number(browsing_l2cpProtocol,  DE_UINT, DE_SIZE_16, PSM_AVCTP_BROWSING);
246                 }
247                 de_pop_sequence(des, browsing_l2cpProtocol);
248 
249                 uint8_t* browsing_avctpProtocol = de_push_sequence(des);
250                 {
251                     de_add_number(browsing_avctpProtocol,  DE_UUID, DE_SIZE_16, BLUETOOTH_PROTOCOL_AVCTP);  // browsing_avctpProtocol_service
252                     de_add_number(browsing_avctpProtocol,  DE_UINT, DE_SIZE_16,  0x0103);    // version
253                 }
254                 de_pop_sequence(des, browsing_avctpProtocol);
255             }
256             de_pop_sequence(attribute, des);
257         }
258         de_pop_sequence(service, attribute);
259     }
260 
261 
262     // 0x0100 "Service Name"
263     de_add_number(service,  DE_UINT, DE_SIZE_16, 0x0100);
264     if (service_name){
265         de_add_data(service,  DE_STRING, strlen(service_name), (uint8_t *) service_name);
266     } else {
267         if (controller){
268             de_add_data(service,  DE_STRING, strlen(default_avrcp_controller_service_name), (uint8_t *) default_avrcp_controller_service_name);
269         } else {
270             de_add_data(service,  DE_STRING, strlen(default_avrcp_target_service_name), (uint8_t *) default_avrcp_target_service_name);
271         }
272     }
273 
274     // 0x0100 "Provider Name"
275     de_add_number(service,  DE_UINT, DE_SIZE_16, 0x0102);
276     if (service_provider_name){
277         de_add_data(service,  DE_STRING, strlen(service_provider_name), (uint8_t *) service_provider_name);
278     } else {
279         if (controller){
280             de_add_data(service,  DE_STRING, strlen(default_avrcp_controller_service_provider_name), (uint8_t *) default_avrcp_controller_service_provider_name);
281         } else {
282             de_add_data(service,  DE_STRING, strlen(default_avrcp_target_service_provider_name), (uint8_t *) default_avrcp_target_service_provider_name);
283         }
284     }
285 
286     // 0x0311 "Supported Features"
287     de_add_number(service, DE_UINT, DE_SIZE_16, 0x0311);
288     de_add_number(service, DE_UINT, DE_SIZE_16, supported_features);
289 }
290 
291 avrcp_connection_t * get_avrcp_connection_for_bd_addr(avrcp_role_t role, bd_addr_t addr){
292     btstack_linked_list_iterator_t it;
293     btstack_linked_list_iterator_init(&it, (btstack_linked_list_t *) &connections);
294     while (btstack_linked_list_iterator_has_next(&it)){
295         avrcp_connection_t * connection = (avrcp_connection_t *)btstack_linked_list_iterator_next(&it);
296         if (connection->role != role) continue;
297         if (memcmp(addr, connection->remote_addr, 6) != 0) continue;
298         return connection;
299     }
300     return NULL;
301 }
302 
303 avrcp_connection_t * get_avrcp_connection_for_l2cap_signaling_cid(avrcp_role_t role, uint16_t l2cap_cid){
304     btstack_linked_list_iterator_t it;
305     btstack_linked_list_iterator_init(&it, (btstack_linked_list_t *) &connections);
306     while (btstack_linked_list_iterator_has_next(&it)){
307         avrcp_connection_t * connection = (avrcp_connection_t *)btstack_linked_list_iterator_next(&it);
308         if (connection->role != role) continue;
309         if (connection->l2cap_signaling_cid != l2cap_cid) continue;
310         return connection;
311     }
312     return NULL;
313 }
314 
315 avrcp_connection_t * get_avrcp_connection_for_avrcp_cid(avrcp_role_t role, uint16_t avrcp_cid){
316     btstack_linked_list_iterator_t it;
317     btstack_linked_list_iterator_init(&it, (btstack_linked_list_t *) &connections);
318     while (btstack_linked_list_iterator_has_next(&it)){
319         avrcp_connection_t * connection = (avrcp_connection_t *)btstack_linked_list_iterator_next(&it);
320         if (connection->role != role) continue;
321         if (connection->avrcp_cid != avrcp_cid) continue;
322         return connection;
323     }
324     return NULL;
325 }
326 
327 avrcp_connection_t * get_avrcp_connection_for_browsing_cid(avrcp_role_t role, uint16_t browsing_cid){
328     btstack_linked_list_iterator_t it;
329     btstack_linked_list_iterator_init(&it, (btstack_linked_list_t *) &connections);
330     while (btstack_linked_list_iterator_has_next(&it)){
331         avrcp_connection_t * connection = (avrcp_connection_t *)btstack_linked_list_iterator_next(&it);
332         if (connection->role != role) continue;
333         if (connection->avrcp_browsing_cid != browsing_cid) continue;
334         return connection;
335     }
336     return NULL;
337 }
338 
339 avrcp_connection_t * get_avrcp_connection_for_browsing_l2cap_cid(avrcp_role_t role, uint16_t browsing_l2cap_cid){
340     btstack_linked_list_iterator_t it;
341     btstack_linked_list_iterator_init(&it, (btstack_linked_list_t *) &connections);
342     while (btstack_linked_list_iterator_has_next(&it)){
343         avrcp_connection_t * connection = (avrcp_connection_t *)btstack_linked_list_iterator_next(&it);
344         if (connection->role != role) continue;
345         if (connection->browsing_connection &&  connection->browsing_connection->l2cap_browsing_cid != browsing_l2cap_cid) continue;
346         return connection;
347     }
348     return NULL;
349 }
350 
351 avrcp_browsing_connection_t * get_avrcp_browsing_connection_for_l2cap_cid(avrcp_role_t role, uint16_t l2cap_cid){
352     btstack_linked_list_iterator_t it;
353     btstack_linked_list_iterator_init(&it, (btstack_linked_list_t *) &connections);
354     while (btstack_linked_list_iterator_has_next(&it)){
355         avrcp_connection_t * connection = (avrcp_connection_t *)btstack_linked_list_iterator_next(&it);
356         if (connection->role != role) continue;
357         if (connection->browsing_connection && connection->browsing_connection->l2cap_browsing_cid != l2cap_cid) continue;
358         return connection->browsing_connection;
359     }
360     return NULL;
361 }
362 
363 void avrcp_request_can_send_now(avrcp_connection_t * connection, uint16_t l2cap_cid){
364     connection->wait_to_send = 1;
365     l2cap_request_can_send_now_event(l2cap_cid);
366 }
367 
368 
369 uint16_t avrcp_get_next_cid(void){
370     avrcp_cid_counter++;
371     if (avrcp_cid_counter == 0){
372         avrcp_cid_counter = 1;
373     }
374     return avrcp_cid_counter;
375 }
376 
377 static avrcp_connection_t * avrcp_create_connection(avrcp_role_t role, bd_addr_t remote_addr){
378     avrcp_connection_t * connection = btstack_memory_avrcp_connection_get();
379     if (!connection){
380         log_error("avrcp: not enough memory to create connection");
381         return NULL;
382     }
383     connection->role = role;
384     connection->state = AVCTP_CONNECTION_IDLE;
385     connection->transaction_label = 0xFF;
386     connection->max_num_fragments = 0xFF;
387     connection->avrcp_cid = avrcp_get_next_cid();
388     memcpy(connection->remote_addr, remote_addr, 6);
389     btstack_linked_list_add(&connections, (btstack_linked_item_t *) connection);
390     return connection;
391 }
392 
393 static void avrcp_finalize_connection(avrcp_connection_t * connection){
394     btstack_linked_list_remove(&connections, (btstack_linked_item_t*) connection);
395     btstack_memory_avrcp_connection_free(connection);
396 }
397 
398 void avrcp_emit_connection_established(btstack_packet_handler_t callback, uint16_t avrcp_cid, bd_addr_t addr, uint8_t status){
399     if (!callback) return;
400     uint8_t event[12];
401     int pos = 0;
402     event[pos++] = HCI_EVENT_AVRCP_META;
403     event[pos++] = sizeof(event) - 2;
404     event[pos++] = AVRCP_SUBEVENT_CONNECTION_ESTABLISHED;
405     event[pos++] = status;
406     reverse_bd_addr(addr,&event[pos]);
407     pos += 6;
408     little_endian_store_16(event, pos, avrcp_cid);
409     pos += 2;
410     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
411 }
412 
413 void avrcp_emit_connection_closed(btstack_packet_handler_t callback, uint16_t avrcp_cid){
414     if (!callback) return;
415     uint8_t event[5];
416     int pos = 0;
417     event[pos++] = HCI_EVENT_AVRCP_META;
418     event[pos++] = sizeof(event) - 2;
419     event[pos++] = AVRCP_SUBEVENT_CONNECTION_RELEASED;
420     little_endian_store_16(event, pos, avrcp_cid);
421     pos += 2;
422     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
423 }
424 
425 void avrcp_handle_sdp_client_query_result(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
426     avrcp_connection_t * connection = get_avrcp_connection_for_avrcp_cid(sdp_query_context->role, sdp_query_context->avrcp_cid);
427     if (!connection) return;
428     if (connection->state != AVCTP_CONNECTION_W4_SDP_QUERY_COMPLETE) return;
429 
430     UNUSED(packet_type);
431     UNUSED(channel);
432     UNUSED(size);
433     uint8_t status;
434     des_iterator_t des_list_it;
435     des_iterator_t prot_it;
436     // uint32_t avdtp_remote_uuid    = 0;
437 
438     switch (hci_event_packet_get_type(packet)){
439         case SDP_EVENT_QUERY_ATTRIBUTE_VALUE:
440             // Handle new SDP record
441             if (sdp_event_query_attribute_byte_get_record_id(packet) != sdp_query_context->record_id) {
442                 sdp_query_context->record_id = sdp_event_query_attribute_byte_get_record_id(packet);
443                 sdp_query_context->parse_sdp_record = 0;
444                 // log_info("SDP Record: Nr: %d", record_id);
445             }
446 
447             if (sdp_event_query_attribute_byte_get_attribute_length(packet) <= attribute_value_buffer_size) {
448                 attribute_value[sdp_event_query_attribute_byte_get_data_offset(packet)] = sdp_event_query_attribute_byte_get_data(packet);
449 
450                 if ((uint16_t)(sdp_event_query_attribute_byte_get_data_offset(packet)+1) == sdp_event_query_attribute_byte_get_attribute_length(packet)) {
451                     switch(sdp_event_query_attribute_byte_get_attribute_id(packet)) {
452                         case BLUETOOTH_ATTRIBUTE_SERVICE_CLASS_ID_LIST:
453                             if (de_get_element_type(attribute_value) != DE_DES) break;
454                             for (des_iterator_init(&des_list_it, attribute_value); des_iterator_has_more(&des_list_it); des_iterator_next(&des_list_it)) {
455                                 uint8_t * element = des_iterator_get_element(&des_list_it);
456                                 if (de_get_element_type(element) != DE_UUID) continue;
457                                 uint32_t uuid = de_get_uuid32(element);
458                                 switch (uuid){
459                                     case BLUETOOTH_SERVICE_CLASS_AV_REMOTE_CONTROL_TARGET:
460                                         if (sdp_query_context->role == AVRCP_CONTROLLER) {
461                                             sdp_query_context->parse_sdp_record = 1;
462                                             break;
463                                         }
464                                         break;
465                                     case BLUETOOTH_SERVICE_CLASS_AV_REMOTE_CONTROL:
466                                     case BLUETOOTH_SERVICE_CLASS_AV_REMOTE_CONTROL_CONTROLLER:
467                                         if (sdp_query_context->role == AVRCP_TARGET) {
468                                             sdp_query_context->parse_sdp_record = 1;
469                                             break;
470                                         }
471                                         break;
472                                     default:
473                                         break;
474                                 }
475                             }
476                             break;
477 
478                         case BLUETOOTH_ATTRIBUTE_PROTOCOL_DESCRIPTOR_LIST: {
479                                 if (!sdp_query_context->parse_sdp_record) break;
480                                 // log_info("SDP Attribute: 0x%04x", sdp_event_query_attribute_byte_get_attribute_id(packet));
481                                 for (des_iterator_init(&des_list_it, attribute_value); des_iterator_has_more(&des_list_it); des_iterator_next(&des_list_it)) {
482                                     uint8_t       *des_element;
483                                     uint8_t       *element;
484                                     uint32_t       uuid;
485 
486                                     if (des_iterator_get_type(&des_list_it) != DE_DES) continue;
487 
488                                     des_element = des_iterator_get_element(&des_list_it);
489                                     des_iterator_init(&prot_it, des_element);
490                                     element = des_iterator_get_element(&prot_it);
491 
492                                     if (de_get_element_type(element) != DE_UUID) continue;
493 
494                                     uuid = de_get_uuid32(element);
495                                     des_iterator_next(&prot_it);
496                                     switch (uuid){
497                                         case BLUETOOTH_PROTOCOL_L2CAP:
498                                             if (!des_iterator_has_more(&prot_it)) continue;
499                                             de_element_get_uint16(des_iterator_get_element(&prot_it), &sdp_query_context->avrcp_l2cap_psm);
500                                             break;
501                                         case BLUETOOTH_PROTOCOL_AVCTP:
502                                             if (!des_iterator_has_more(&prot_it)) continue;
503                                             de_element_get_uint16(des_iterator_get_element(&prot_it), &sdp_query_context->avrcp_version);
504                                             break;
505                                         default:
506                                             break;
507                                     }
508                                 }
509                             }
510                             break;
511                         case BLUETOOTH_ATTRIBUTE_ADDITIONAL_PROTOCOL_DESCRIPTOR_LISTS: {
512                                 // log_info("SDP Attribute: 0x%04x", sdp_event_query_attribute_byte_get_attribute_id(packet));
513                                 if (!sdp_query_context->parse_sdp_record) break;
514                                 if (de_get_element_type(attribute_value) != DE_DES) break;
515 
516                                 des_iterator_t des_list_0_it;
517                                 uint8_t       *element_0;
518 
519                                 des_iterator_init(&des_list_0_it, attribute_value);
520                                 element_0 = des_iterator_get_element(&des_list_0_it);
521 
522                                 for (des_iterator_init(&des_list_it, element_0); des_iterator_has_more(&des_list_it); des_iterator_next(&des_list_it)) {
523                                     uint8_t       *des_element;
524                                     uint8_t       *element;
525                                     uint32_t       uuid;
526 
527                                     if (des_iterator_get_type(&des_list_it) != DE_DES) continue;
528 
529                                     des_element = des_iterator_get_element(&des_list_it);
530                                     des_iterator_init(&prot_it, des_element);
531                                     element = des_iterator_get_element(&prot_it);
532 
533                                     if (de_get_element_type(element) != DE_UUID) continue;
534 
535                                     uuid = de_get_uuid32(element);
536                                     des_iterator_next(&prot_it);
537                                     switch (uuid){
538                                         case BLUETOOTH_PROTOCOL_L2CAP:
539                                             if (!des_iterator_has_more(&prot_it)) continue;
540                                             de_element_get_uint16(des_iterator_get_element(&prot_it), &connection->browsing_l2cap_psm);
541                                             break;
542                                         case BLUETOOTH_PROTOCOL_AVCTP:
543                                             if (!des_iterator_has_more(&prot_it)) continue;
544                                             de_element_get_uint16(des_iterator_get_element(&prot_it), &connection->browsing_version);
545                                             break;
546                                         default:
547                                             break;
548                                     }
549                                 }
550                             }
551                             break;
552                         default:
553                             break;
554                     }
555                 }
556             } else {
557                 log_error("SDP attribute value buffer size exceeded: available %d, required %d", attribute_value_buffer_size, sdp_event_query_attribute_byte_get_attribute_length(packet));
558             }
559             break;
560 
561         case SDP_EVENT_QUERY_COMPLETE:{
562             status = sdp_event_query_complete_get_status(packet);
563 
564             if (status != ERROR_CODE_SUCCESS){
565                 log_info("AVRCP: SDP query failed with status 0x%02x.", status);
566                 avrcp_emit_connection_established(sdp_query_context->avrcp_callback, connection->avrcp_cid, connection->remote_addr, status);
567                 avrcp_finalize_connection(connection);
568                 break;
569             }
570 
571             if (!sdp_query_context->avrcp_l2cap_psm){
572                 connection->state = AVCTP_CONNECTION_IDLE;
573                 log_info("AVRCP: no suitable service found");
574                 avrcp_emit_connection_established(sdp_query_context->avrcp_callback, connection->avrcp_cid, connection->remote_addr, SDP_SERVICE_NOT_FOUND);
575                 avrcp_finalize_connection(connection);
576                 break;
577             }
578             connection->state = AVCTP_CONNECTION_W4_L2CAP_CONNECTED;
579             l2cap_create_channel(sdp_query_context->packet_handler, connection->remote_addr, sdp_query_context->avrcp_l2cap_psm, l2cap_max_mtu(), NULL);
580             break;
581         }
582     }
583 }
584 
585 void avrcp_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size, avrcp_context_t * context){
586     UNUSED(channel);
587     UNUSED(size);
588     bd_addr_t event_addr;
589     uint16_t local_cid;
590     uint8_t  status;
591     avrcp_connection_t * connection = NULL;
592     uint16_t psm;
593 
594     if (packet_type != HCI_EVENT_PACKET) return;
595 
596     switch (hci_event_packet_get_type(packet)) {
597         case HCI_EVENT_DISCONNECTION_COMPLETE:
598             avrcp_emit_connection_closed(context->avrcp_callback, 0);
599             break;
600         case L2CAP_EVENT_INCOMING_CONNECTION:
601             l2cap_event_incoming_connection_get_address(packet, event_addr);
602             local_cid = l2cap_event_incoming_connection_get_local_cid(packet);
603             connection = avrcp_create_connection(context->role, event_addr);
604             if (!connection) {
605                 log_error("Failed to alloc connection structure");
606                 l2cap_decline_connection(local_cid);
607                 break;
608             }
609 
610             psm = l2cap_event_incoming_connection_get_psm(packet);
611             if (psm == PSM_AVCTP){
612                 if (!connection->l2cap_signaling_cid){
613                     connection->state = AVCTP_CONNECTION_W4_L2CAP_CONNECTED;
614                     connection->l2cap_signaling_cid = local_cid;
615                     log_info("L2CAP_EVENT_INCOMING_CONNECTION avrcp_cid 0x%02x, l2cap_signaling_cid 0x%02x", connection->avrcp_cid, connection->l2cap_signaling_cid);
616                     l2cap_accept_connection(local_cid);
617                     break;
618                 }
619             }
620             log_info("L2CAP_EVENT_INCOMING_CONNECTION local_cid 0x%02x, psm 0x%2x, decline connection", local_cid, psm);
621             l2cap_decline_connection(local_cid);
622             break;
623 
624         case L2CAP_EVENT_CHANNEL_OPENED:
625             l2cap_event_channel_opened_get_address(packet, event_addr);
626             status = l2cap_event_channel_opened_get_status(packet);
627             local_cid = l2cap_event_channel_opened_get_local_cid(packet);
628 
629             connection = get_avrcp_connection_for_bd_addr(context->role, event_addr);
630             if (!connection){
631                 // TODO: validate if this cannot happen. If not,  drop disconnect call
632                 log_error("AVRCP connection lookup failed");
633                 l2cap_disconnect(local_cid, 0); // reason isn't used
634                 break;
635             }
636             if (status != ERROR_CODE_SUCCESS){
637                 log_info("L2CAP connection to connection %s failed. status code 0x%02x", bd_addr_to_str(event_addr), status);
638                 avrcp_emit_connection_established(context->avrcp_callback, connection->avrcp_cid, event_addr, status);
639                 avrcp_finalize_connection(connection);
640                 break;
641             }
642 
643             psm = l2cap_event_channel_opened_get_psm(packet);
644             if (psm == PSM_AVCTP){
645                 connection->l2cap_signaling_cid = local_cid;
646                 connection->l2cap_mtu = l2cap_event_channel_opened_get_remote_mtu(packet);
647                 connection->song_length_ms = 0xFFFFFFFF;
648                 connection->song_position_ms = 0xFFFFFFFF;
649                 connection->playback_status = AVRCP_PLAYBACK_STATUS_ERROR;
650 
651                 log_info("L2CAP_EVENT_CHANNEL_OPENED avrcp_cid 0x%02x, l2cap_signaling_cid 0x%02x", connection->avrcp_cid, connection->l2cap_signaling_cid);
652                 connection->state = AVCTP_CONNECTION_OPENED;
653                 avrcp_emit_connection_established(context->avrcp_callback, connection->avrcp_cid, event_addr, ERROR_CODE_SUCCESS);
654             }
655             break;
656 
657         case L2CAP_EVENT_CHANNEL_CLOSED:
658             // data: event (8), len(8), channel (16)
659             local_cid = l2cap_event_channel_closed_get_local_cid(packet);
660             connection = get_avrcp_connection_for_l2cap_signaling_cid(context->role, local_cid);
661             if (connection){
662                 avrcp_emit_connection_closed(context->avrcp_callback, connection->avrcp_cid);
663                 avrcp_finalize_connection(connection);
664                 break;
665             }
666             break;
667         default:
668             break;
669     }
670 }
671 
672 uint8_t avrcp_connect(avrcp_role_t role, bd_addr_t bd_addr, avrcp_context_t * context, uint16_t * avrcp_cid){
673     avrcp_connection_t * connection = get_avrcp_connection_for_bd_addr(context->role, bd_addr);
674     if (connection) return ERROR_CODE_COMMAND_DISALLOWED;
675 
676     if (!sdp_client_ready()) return ERROR_CODE_COMMAND_DISALLOWED;
677 
678     connection = avrcp_create_connection(role, bd_addr);
679     if (!connection){
680         log_error("avrcp: could not allocate connection struct.");
681         return BTSTACK_MEMORY_ALLOC_FAILED;
682     }
683 
684     if (avrcp_cid){
685         *avrcp_cid = connection->avrcp_cid;
686     }
687 
688     context->avrcp_l2cap_psm = 0;
689     context->avrcp_version = 0;
690     context->avrcp_cid = connection->avrcp_cid;
691     connection->browsing_l2cap_psm = 0;
692     connection->state = AVCTP_CONNECTION_W4_SDP_QUERY_COMPLETE;
693 
694     sdp_query_context = context;
695     sdp_client_query_uuid16(&avrcp_handle_sdp_client_query_result, connection->remote_addr, BLUETOOTH_PROTOCOL_AVCTP);
696     return ERROR_CODE_SUCCESS;
697 }
698 
699 void avrcp_init(void){
700     connections = NULL;
701 }
702