xref: /btstack/src/classic/a2dp_source.c (revision 83733477bbd724a2c7c0467d67f0d9c6394251c0)
1 
2 /*
3  * Copyright (C) 2016 BlueKitchen GmbH
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  *
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. Neither the name of the copyright holders nor the names of
15  *    contributors may be used to endorse or promote products derived
16  *    from this software without specific prior written permission.
17  * 4. Any redistribution, use, or modification is done solely for
18  *    personal benefit and not for any commercial purpose or for
19  *    monetary gain.
20  *
21  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
25  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
28  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
31  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  * Please inquire about commercial licensing options at
35  * [email protected]
36  *
37  */
38 
39 /**
40  * Supported use cases:
41  * - single incoming connection: sep discovery starts and stream will get setup if remote sink sep with SBC is found
42  * - single outgoing connection: see above
43  * - outgoing and incoming connection to same device:
44  *    - if outgoing is triggered first, incoming will get ignored.
45  *    - if incoming starts first, start ougoing will fail, but incoming will succeed.
46  * - outgoing and incoming connections to different devices:
47  *    - if outgoing is first, incoming gets ignored.
48  *    - if incoming starts first SEP discovery will get stopped and outgoing will succeed.
49  */
50 
51 #define BTSTACK_FILE__ "a2dp_source.c"
52 
53 #include <stdint.h>
54 #include <string.h>
55 
56 #include "bluetooth_psm.h"
57 #include "bluetooth_sdp.h"
58 #include "btstack_debug.h"
59 #include "btstack_event.h"
60 #include "classic/a2dp_source.h"
61 #include "classic/avdtp_source.h"
62 #include "classic/avdtp_util.h"
63 #include "classic/sdp_util.h"
64 #include "l2cap.h"
65 
66 #define AVDTP_MAX_SEP_NUM 10
67 #define A2DP_SET_CONFIG_DELAY_MS 150
68 
69 static const char * default_a2dp_source_service_name = "BTstack A2DP Source Service";
70 static const char * default_a2dp_source_service_provider_name = "BTstack A2DP Source Service Provider";
71 
72 static btstack_timer_source_t a2dp_source_set_config_timer;
73 
74 //
75 static bool     outgoing_active;
76 
77 // discover remote seps
78 static a2dp_state_t a2dp_source_state = A2DP_IDLE;
79 static uint16_t     a2dp_source_cid;
80 static uint16_t     num_remote_seps = 0;
81 static avdtp_sep_t  remote_seps[AVDTP_MAX_SEP_NUM];
82 
83 static bool stream_endpoint_configured = false;
84 
85 static avdtp_stream_endpoint_context_t sc;
86 static btstack_packet_handler_t a2dp_source_packet_handler_user;
87 
88 static void a2dp_source_packet_handler_internal(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
89 static void a2dp_discover_seps_with_next_waiting_connection(void);
90 
91 static void a2dp_source_streaming_emit_connection_failed(avdtp_connection_t * connection, uint8_t local_seid, uint8_t status) {
92     uint8_t event[14];
93     int pos = 0;
94     event[pos++] = HCI_EVENT_A2DP_META;
95     event[pos++] = sizeof(event) - 2;
96     event[pos++] = A2DP_SUBEVENT_STREAM_ESTABLISHED;
97     little_endian_store_16(event, pos, connection->avdtp_cid);
98     pos += 2;
99     reverse_bd_addr(connection->remote_addr, &event[pos]);
100     pos += 6;
101     event[pos++] = local_seid;
102     event[pos++] = 0;
103     event[pos++] = status;
104 
105     (*a2dp_source_packet_handler_user)(HCI_EVENT_PACKET, 0, event, sizeof(event));
106 }
107 
108 void a2dp_source_create_sdp_record(uint8_t * service, uint32_t service_record_handle, uint16_t supported_features, const char * service_name, const char * service_provider_name){
109     uint8_t* attribute;
110     de_create_sequence(service);
111 
112     // 0x0000 "Service Record Handle"
113     de_add_number(service, DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_SERVICE_RECORD_HANDLE);
114     de_add_number(service, DE_UINT, DE_SIZE_32, service_record_handle);
115 
116     // 0x0001 "Service Class ID List"
117     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_SERVICE_CLASS_ID_LIST);
118     attribute = de_push_sequence(service);
119     {
120         de_add_number(attribute, DE_UUID, DE_SIZE_16, BLUETOOTH_SERVICE_CLASS_AUDIO_SOURCE);
121     }
122     de_pop_sequence(service, attribute);
123 
124     // 0x0004 "Protocol Descriptor List"
125     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_PROTOCOL_DESCRIPTOR_LIST);
126     attribute = de_push_sequence(service);
127     {
128         uint8_t* l2cpProtocol = de_push_sequence(attribute);
129         {
130             de_add_number(l2cpProtocol,  DE_UUID, DE_SIZE_16, BLUETOOTH_PROTOCOL_L2CAP);
131             de_add_number(l2cpProtocol,  DE_UINT, DE_SIZE_16, BLUETOOTH_PSM_AVDTP);
132         }
133         de_pop_sequence(attribute, l2cpProtocol);
134 
135         uint8_t* avProtocol = de_push_sequence(attribute);
136         {
137             de_add_number(avProtocol,  DE_UUID, DE_SIZE_16, BLUETOOTH_PROTOCOL_AVDTP);  // avProtocol_service
138             de_add_number(avProtocol,  DE_UINT, DE_SIZE_16,  0x0103);  // version
139         }
140         de_pop_sequence(attribute, avProtocol);
141     }
142     de_pop_sequence(service, attribute);
143 
144     // 0x0005 "Public Browse Group"
145     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_BROWSE_GROUP_LIST); // public browse group
146     attribute = de_push_sequence(service);
147     {
148         de_add_number(attribute,  DE_UUID, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_PUBLIC_BROWSE_ROOT);
149     }
150     de_pop_sequence(service, attribute);
151 
152     // 0x0009 "Bluetooth Profile Descriptor List"
153     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_BLUETOOTH_PROFILE_DESCRIPTOR_LIST);
154     attribute = de_push_sequence(service);
155     {
156         uint8_t *a2dProfile = de_push_sequence(attribute);
157         {
158             de_add_number(a2dProfile,  DE_UUID, DE_SIZE_16, BLUETOOTH_SERVICE_CLASS_ADVANCED_AUDIO_DISTRIBUTION);
159             de_add_number(a2dProfile,  DE_UINT, DE_SIZE_16, 0x0103);
160         }
161         de_pop_sequence(attribute, a2dProfile);
162     }
163     de_pop_sequence(service, attribute);
164 
165 
166     // 0x0100 "Service Name"
167     de_add_number(service,  DE_UINT, DE_SIZE_16, 0x0100);
168     if (service_name){
169         de_add_data(service,  DE_STRING, strlen(service_name), (uint8_t *) service_name);
170     } else {
171         de_add_data(service,  DE_STRING, strlen(default_a2dp_source_service_name), (uint8_t *) default_a2dp_source_service_name);
172     }
173 
174     // 0x0100 "Provider Name"
175     de_add_number(service,  DE_UINT, DE_SIZE_16, 0x0102);
176     if (service_provider_name){
177         de_add_data(service,  DE_STRING, strlen(service_provider_name), (uint8_t *) service_provider_name);
178     } else {
179         de_add_data(service,  DE_STRING, strlen(default_a2dp_source_service_provider_name), (uint8_t *) default_a2dp_source_service_provider_name);
180     }
181 
182     // 0x0311 "Supported Features"
183     de_add_number(service, DE_UINT, DE_SIZE_16, 0x0311);
184     de_add_number(service, DE_UINT, DE_SIZE_16, supported_features);
185 }
186 
187 static void a2dp_signaling_emit_reconfigured(uint16_t cid, uint8_t local_seid, uint8_t status){
188     uint8_t event[7];
189     int pos = 0;
190     event[pos++] = HCI_EVENT_A2DP_META;
191     event[pos++] = sizeof(event) - 2;
192     event[pos++] = A2DP_SUBEVENT_STREAM_RECONFIGURED;
193     little_endian_store_16(event, pos, cid);
194     pos += 2;
195     event[pos++] = local_seid;
196     event[pos++] = status;
197     (*a2dp_source_packet_handler_user)(HCI_EVENT_PACKET, 0, event, sizeof(event));
198 }
199 
200 static void a2dp_source_discover_stream_endpoints(uint16_t avdtp_cid){
201     a2dp_source_cid = avdtp_cid;
202     avdtp_source_discover_stream_endpoints(avdtp_cid);
203 }
204 
205 static void a2dp_source_set_config_timer_handler(btstack_timer_source_t * timer){
206     if (stream_endpoint_configured) return;
207 
208     uint16_t avdtp_cid = (uint16_t)(uintptr_t) btstack_run_loop_get_timer_context(timer);
209     avdtp_connection_t * connection = avdtp_get_connection_for_avdtp_cid(avdtp_cid);
210 
211     if (connection == NULL) {
212         log_info("a2dp_discover_seps_with_next_waiting_connection");
213         a2dp_discover_seps_with_next_waiting_connection();
214         return;
215     }
216 
217     a2dp_source_discover_stream_endpoints(avdtp_cid);
218 }
219 
220 static void a2dp_source_set_config_timer_start(uint16_t avdtp_cid){
221     log_info("a2dp_source_set_config_timer_start cid 0%02x", avdtp_cid);
222     btstack_run_loop_remove_timer(&a2dp_source_set_config_timer);
223     btstack_run_loop_set_timer_handler(&a2dp_source_set_config_timer,a2dp_source_set_config_timer_handler);
224     btstack_run_loop_set_timer(&a2dp_source_set_config_timer, A2DP_SET_CONFIG_DELAY_MS);
225     btstack_run_loop_set_timer_context(&a2dp_source_set_config_timer, (void *)(uintptr_t)avdtp_cid);
226     btstack_run_loop_add_timer(&a2dp_source_set_config_timer);
227 }
228 
229 static void a2dp_source_set_config_timer_stop(void){
230     log_info("a2dp_source_set_config_timer_stop");
231     btstack_run_loop_remove_timer(&a2dp_source_set_config_timer);
232 }
233 
234 static void a2dp_start_discovering_seps(avdtp_connection_t * connection){
235     a2dp_source_state = A2DP_DISCOVER_SEPS;
236     sc.active_remote_sep_index = 0;
237     num_remote_seps = 0;
238     memset(remote_seps, 0, sizeof(avdtp_sep_t) * AVDTP_MAX_SEP_NUM);
239     connection->a2dp_source_discover_seps = false;
240 
241     // if we initiated the connection, start config right away, else wait a bit to give remote a chance to do it first
242     if (outgoing_active && (a2dp_source_cid == connection->avdtp_cid)){
243         log_info("discover seps");
244         a2dp_source_discover_stream_endpoints(connection->avdtp_cid);
245     } else {
246         log_info("wait a bit, then discover seps");
247         a2dp_source_set_config_timer_start(connection->avdtp_cid);
248     }
249 }
250 
251 static void a2dp_discover_seps_with_next_waiting_connection(void){
252     a2dp_source_state = A2DP_IDLE;
253 
254     btstack_linked_list_iterator_t it;
255     btstack_linked_list_iterator_init(&it, avdtp_get_connections());
256     while (btstack_linked_list_iterator_has_next(&it)){
257         avdtp_connection_t * next_connection = (avdtp_connection_t *)btstack_linked_list_iterator_next(&it);
258         if (!next_connection->a2dp_source_discover_seps) continue;
259         a2dp_start_discovering_seps(next_connection);
260     }
261 }
262 
263 static void a2dp_source_packet_handler_internal(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
264     UNUSED(channel);
265     UNUSED(size);
266 
267     uint16_t cid;
268     avdtp_connection_t * connection;
269 
270     uint8_t signal_identifier;
271     uint8_t status;
272     uint8_t local_seid;
273     uint8_t remote_seid;
274     bd_addr_t address;
275 
276     if (packet_type != HCI_EVENT_PACKET) return;
277     if (hci_event_packet_get_type(packet) != HCI_EVENT_AVDTP_META) return;
278 
279     switch (packet[2]){
280         case AVDTP_SUBEVENT_SIGNALING_CONNECTION_ESTABLISHED:
281             if (sc.local_stream_endpoint == NULL) return;
282 
283             cid = avdtp_subevent_signaling_connection_established_get_avdtp_cid(packet);
284             connection = avdtp_get_connection_for_avdtp_cid(cid);
285             btstack_assert(connection != NULL);
286 
287             avdtp_subevent_signaling_connection_established_get_bd_addr(packet, address);
288 
289             status = avdtp_subevent_signaling_connection_established_get_status(packet);
290             if (status != ERROR_CODE_SUCCESS){
291                 // notify about connection error only if we're initiator
292                 if (outgoing_active && (a2dp_source_cid == cid)){
293                     log_info("A2DP source signaling connection failed status 0x%02x", status);
294                     outgoing_active = false;
295                     a2dp_emit_signaling_connection_established(a2dp_source_packet_handler_user, packet, size, status);
296                 }
297                 break;
298             }
299             log_info("A2DP source signaling connection established avdtp_cid 0x%02x", cid);
300 
301             // notify app
302             a2dp_emit_signaling_connection_established(a2dp_source_packet_handler_user, packet, size, status);
303 
304             // we already have a valid setup
305             if (stream_endpoint_configured) return;
306 
307             // start discover seps now if:
308             // - outgoing active: signaling for outgoing connection
309             // - outgoing not active: incoming connection and no sep discover ongoing
310             log_info("outgoing_active %d, a2dp_source_cid 0x%02x, cid  0x%02x, a2dp_source_state %d", outgoing_active, a2dp_source_cid, cid, a2dp_source_state);
311             if ((outgoing_active && (a2dp_source_cid == cid)) || (!outgoing_active && (a2dp_source_state == A2DP_IDLE))){
312                 a2dp_start_discovering_seps(connection);
313             } else {
314                 // post-pone sep discovery
315                 connection->a2dp_source_discover_seps = true;
316             }
317             break;
318 
319         case AVDTP_SUBEVENT_SIGNALING_SEP_FOUND:
320             cid = avdtp_subevent_signaling_sep_found_get_avdtp_cid(packet);
321             if (a2dp_source_cid != cid) break;
322             if (a2dp_source_state == A2DP_DISCOVER_SEPS) {
323                 avdtp_sep_t sep;
324                 sep.seid       = avdtp_subevent_signaling_sep_found_get_remote_seid(packet);;
325                 sep.in_use     = avdtp_subevent_signaling_sep_found_get_in_use(packet);
326                 sep.media_type = (avdtp_media_type_t) avdtp_subevent_signaling_sep_found_get_media_type(packet);
327                 sep.type       = (avdtp_sep_type_t) avdtp_subevent_signaling_sep_found_get_sep_type(packet);
328                 log_info("A2DP Found sep: remote seid 0x%02x, in_use %d, media type %d, sep type %s, index %d",
329                          sep.seid, sep.in_use, sep.media_type, sep.type == AVDTP_SOURCE ? "source" : "sink",
330                          num_remote_seps);
331                 if (sep.type == AVDTP_SINK) {
332                     remote_seps[num_remote_seps++] = sep;
333                 }
334             }
335             break;
336 
337         case AVDTP_SUBEVENT_SIGNALING_SEP_DICOVERY_DONE:
338             cid = avdtp_subevent_signaling_sep_dicovery_done_get_avdtp_cid(packet);
339             if (a2dp_source_cid != cid) break;
340             if (a2dp_source_state != A2DP_DISCOVER_SEPS) break;
341 
342             connection = avdtp_get_connection_for_avdtp_cid(cid);
343             btstack_assert(connection != NULL);
344 
345             if (num_remote_seps > 0){
346                 a2dp_source_state = A2DP_GET_CAPABILITIES;
347                 connection->supported_codecs_bitmap = 0;
348                 sc.active_remote_sep_index = 0;
349             } else {
350                 if (outgoing_active){
351                     outgoing_active = false;
352                     connection = avdtp_get_connection_for_avdtp_cid(cid);
353                     btstack_assert(connection != NULL);
354                     a2dp_source_streaming_emit_connection_failed(connection, sc.local_stream_endpoint->sep.seid, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_NO_SUITABLE_CHANNEL_FOUND);
355                 }
356 
357                 // continue
358                 a2dp_discover_seps_with_next_waiting_connection();
359             }
360             break;
361 
362         case AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CAPABILITY:
363             cid = avdtp_subevent_signaling_media_codec_sbc_capability_get_avdtp_cid(packet);
364             if (a2dp_source_cid != cid) break;
365             if (a2dp_source_state == A2DP_GET_CAPABILITIES) {
366 
367                 log_info("A2DP received SBC capability, received: local seid 0x%02x, remote seid 0x%02x, expected: local seid 0x%02x, remote seid 0x%02x",
368                     avdtp_subevent_signaling_media_codec_sbc_capability_get_local_seid(packet),
369                     avdtp_subevent_signaling_media_codec_sbc_capability_get_remote_seid(packet),
370                     avdtp_stream_endpoint_seid(sc.local_stream_endpoint), remote_seps[sc.active_remote_sep_index].seid );
371 
372                 connection = avdtp_get_connection_for_avdtp_cid(cid);
373                 btstack_assert(connection != NULL);
374 
375                 uint8_t sampling_frequency = avdtp_choose_sbc_sampling_frequency(sc.local_stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_sampling_frequency_bitmap(packet));
376                 uint8_t channel_mode = avdtp_choose_sbc_channel_mode(sc.local_stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_channel_mode_bitmap(packet));
377                 uint8_t block_length = avdtp_choose_sbc_block_length(sc.local_stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_block_length_bitmap(packet));
378                 uint8_t subbands = avdtp_choose_sbc_subbands(sc.local_stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_subbands_bitmap(packet));
379 
380                 uint8_t allocation_method = avdtp_choose_sbc_allocation_method(sc.local_stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_allocation_method_bitmap(packet));
381                 uint8_t max_bitpool_value = avdtp_choose_sbc_max_bitpool_value(sc.local_stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_max_bitpool_value(packet));
382                 uint8_t min_bitpool_value = avdtp_choose_sbc_min_bitpool_value(sc.local_stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_min_bitpool_value(packet));
383 
384                 sc.local_stream_endpoint->remote_configuration.media_codec.media_codec_information[0] = (sampling_frequency << 4) | channel_mode;
385                 sc.local_stream_endpoint->remote_configuration.media_codec.media_codec_information[1] = (block_length << 4) | (subbands << 2) | allocation_method;
386                 sc.local_stream_endpoint->remote_configuration.media_codec.media_codec_information[2] = min_bitpool_value;
387                 sc.local_stream_endpoint->remote_configuration.media_codec.media_codec_information[3] = max_bitpool_value;
388 
389                 sc.local_stream_endpoint->remote_configuration_bitmap = store_bit16(sc.local_stream_endpoint->remote_configuration_bitmap, AVDTP_MEDIA_CODEC, 1);
390                 sc.local_stream_endpoint->remote_configuration.media_codec.media_type = AVDTP_AUDIO;
391                 sc.local_stream_endpoint->remote_configuration.media_codec.media_codec_type = AVDTP_CODEC_SBC;
392 
393                 // suitable Sink SEP found, configure SEP
394                 a2dp_source_state = A2DP_SET_CONFIGURATION;
395                 connection->supported_codecs_bitmap |= (1 << AVDTP_CODEC_SBC);
396             }
397             break;
398 
399         case AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_OTHER_CAPABILITY:
400             log_info("received non SBC codec. not implemented");
401             break;
402 
403         case AVDTP_SUBEVENT_SIGNALING_MEDIA_TRANSPORT_CAPABILITY:
404             log_info("received, but not forwarded: AVDTP_SUBEVENT_SIGNALING_MEDIA_TRANSPORT_CAPABILITY, remote seid 0x%02x", avdtp_subevent_signaling_media_transport_capability_get_remote_seid(packet));
405             break;
406         case AVDTP_SUBEVENT_SIGNALING_REPORTING_CAPABILITY:
407             log_info("received, but not forwarded: AVDTP_SUBEVENT_SIGNALING_REPORTING_CAPABILITY, remote seid 0x%02x", avdtp_subevent_signaling_reporting_capability_get_remote_seid(packet));
408             break;
409         case AVDTP_SUBEVENT_SIGNALING_RECOVERY_CAPABILITY:
410             log_info("received, but not forwarded: AVDTP_SUBEVENT_SIGNALING_RECOVERY_CAPABILITY, remote seid 0x%02x", avdtp_subevent_signaling_recovery_capability_get_remote_seid(packet));
411             break;
412         case AVDTP_SUBEVENT_SIGNALING_CONTENT_PROTECTION_CAPABILITY:
413             log_info("received, but not forwarded: AVDTP_SUBEVENT_SIGNALING_CONTENT_PROTECTION_CAPABILITY, remote seid 0x%02x", avdtp_subevent_signaling_content_protection_capability_get_remote_seid(packet));
414             break;
415         case AVDTP_SUBEVENT_SIGNALING_HEADER_COMPRESSION_CAPABILITY:
416             log_info("received, but not forwarded: AVDTP_SUBEVENT_SIGNALING_HEADER_COMPRESSION_CAPABILITY, remote seid 0x%02x", avdtp_subevent_signaling_header_compression_capability_get_remote_seid(packet));
417             break;
418         case AVDTP_SUBEVENT_SIGNALING_MULTIPLEXING_CAPABILITY:
419             log_info("received, but not forwarded: AVDTP_SUBEVENT_SIGNALING_MULTIPLEXING_CAPABILITY, remote seid 0x%02x", avdtp_subevent_signaling_multiplexing_capability_get_remote_seid(packet));
420             break;
421 
422         case AVDTP_SUBEVENT_SIGNALING_DELAY_REPORTING_CAPABILITY:
423             cid = avdtp_subevent_signaling_delay_reporting_capability_get_avdtp_cid(packet);
424             if (a2dp_source_cid != cid) break;
425             if (a2dp_source_state != A2DP_GET_CAPABILITIES) break;
426 
427             sc.local_stream_endpoint->remote_configuration_bitmap = store_bit16(sc.local_stream_endpoint->remote_configuration_bitmap, AVDTP_DELAY_REPORTING, 1);
428             a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_SIGNALING_DELAY_REPORTING_CAPABILITY);
429             break;
430 
431         case AVDTP_SUBEVENT_SIGNALING_CAPABILITIES_DONE:
432             cid = avdtp_subevent_signaling_capabilities_done_get_avdtp_cid(packet);
433             if (a2dp_source_cid != cid) break;
434             if (a2dp_source_state != A2DP_GET_CAPABILITIES) break;
435 
436             // endpoint was not suitable, check next one
437             sc.active_remote_sep_index++;
438             if (sc.active_remote_sep_index >= num_remote_seps){
439                 // we didn't find a suitable SBC stream endpoint, sorry.
440                 if (outgoing_active){
441                     outgoing_active = false;
442                     connection = avdtp_get_connection_for_avdtp_cid(cid);
443                     btstack_assert(connection != NULL);
444                     a2dp_source_streaming_emit_connection_failed(connection, sc.local_stream_endpoint->sep.seid, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_NO_SUITABLE_CHANNEL_FOUND);
445                 }
446                 a2dp_discover_seps_with_next_waiting_connection();
447             }
448             break;
449 
450         case AVDTP_SUBEVENT_SIGNALING_DELAY_REPORT:
451             cid = avdtp_subevent_signaling_delay_report_get_avdtp_cid(packet);
452             if (a2dp_source_cid != cid) break;
453             a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_SIGNALING_DELAY_REPORT);
454             break;
455 
456         case AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CONFIGURATION:
457             cid = avdtp_subevent_signaling_media_codec_sbc_configuration_get_avdtp_cid(packet);
458             if (a2dp_source_cid != cid) break;
459 
460             switch (a2dp_source_state){
461                 case A2DP_W4_SET_CONFIGURATION:
462                     // discovery and config of remote sink sep successful
463                     stream_endpoint_configured = true;
464                     a2dp_source_set_config_timer_stop();
465 
466                     a2dp_source_state = A2DP_W2_OPEN_STREAM_WITH_SEID;
467                     break;
468                 default:
469                     return;
470             }
471 
472             sc.sampling_frequency = avdtp_subevent_signaling_media_codec_sbc_configuration_get_sampling_frequency(packet);
473             sc.channel_mode = avdtp_subevent_signaling_media_codec_sbc_configuration_get_channel_mode(packet);
474             sc.block_length = avdtp_subevent_signaling_media_codec_sbc_configuration_get_block_length(packet);
475             sc.subbands = avdtp_subevent_signaling_media_codec_sbc_configuration_get_subbands(packet);
476             sc.allocation_method = avdtp_subevent_signaling_media_codec_sbc_configuration_get_allocation_method(packet);
477             sc.max_bitpool_value = avdtp_subevent_signaling_media_codec_sbc_configuration_get_max_bitpool_value(packet);
478             sc.min_bitpool_value = avdtp_subevent_signaling_media_codec_sbc_configuration_get_min_bitpool_value(packet);
479 
480             log_info("A2DP received SBC Config: sample rate %u, max bitpool %u., remote seid 0x%02x", sc.sampling_frequency, sc.max_bitpool_value, avdtp_subevent_signaling_media_codec_sbc_configuration_get_remote_seid(packet));
481             a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CONFIGURATION);
482             break;
483 
484         case AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_OTHER_CONFIGURATION:
485             break;
486 
487         case AVDTP_SUBEVENT_STREAMING_CAN_SEND_MEDIA_PACKET_NOW:
488             a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_STREAMING_CAN_SEND_MEDIA_PACKET_NOW);
489             break;
490 
491         case AVDTP_SUBEVENT_STREAMING_CONNECTION_ESTABLISHED:
492             cid = avdtp_subevent_streaming_connection_established_get_avdtp_cid(packet);
493             if (a2dp_source_cid != cid) break;
494             if (a2dp_source_state != A2DP_W4_OPEN_STREAM_WITH_SEID) break;
495 
496             if (outgoing_active){
497                 outgoing_active = false;
498             }
499 
500             remote_seid = avdtp_subevent_streaming_connection_established_get_remote_seid(packet);
501             local_seid  = avdtp_subevent_streaming_connection_established_get_local_seid(packet);
502             status = avdtp_subevent_streaming_connection_established_get_status(packet);
503             if (status != ERROR_CODE_SUCCESS){
504                 log_info("A2DP source streaming connection could not be established, avdtp_cid 0x%02x, status 0x%02x ---", cid, status);
505                 a2dp_emit_streaming_connection_established(a2dp_source_packet_handler_user, packet, size, status);
506                 break;
507             }
508 
509             log_info("A2DP source streaming connection established --- avdtp_cid 0x%02x, local seid 0x%02x, remote seid 0x%02x", cid, local_seid, remote_seid);
510             a2dp_source_state = A2DP_STREAMING_OPENED;
511             a2dp_emit_streaming_connection_established(a2dp_source_packet_handler_user, packet, size, status);
512             break;
513 
514         case AVDTP_SUBEVENT_SIGNALING_ACCEPT:
515             cid = avdtp_subevent_signaling_accept_get_avdtp_cid(packet);
516             if (a2dp_source_cid != cid) break;
517 
518             if (avdtp_subevent_signaling_accept_get_is_initiator(packet) == 0) break;
519 
520             signal_identifier = avdtp_subevent_signaling_accept_get_signal_identifier(packet);
521 
522             log_info("A2DP cmd %s accepted, global state %d, is_initiator %u, cid 0x%2x, local seid 0x%02x", avdtp_si2str(signal_identifier), a2dp_source_state,
523                      avdtp_subevent_signaling_accept_get_is_initiator(packet), cid, avdtp_subevent_signaling_accept_get_local_seid(packet));
524 
525             switch (a2dp_source_state){
526                 case A2DP_GET_CAPABILITIES:
527                     remote_seid = remote_seps[sc.active_remote_sep_index].seid;
528                     log_info("A2DP get capabilities for remote seid 0x%02x", remote_seid);
529                     avdtp_source_get_all_capabilities(cid, remote_seid);
530                     return;
531 
532                 case A2DP_SET_CONFIGURATION:
533                     remote_seid = remote_seps[sc.active_remote_sep_index].seid;
534                     log_info("A2DP initiate set configuration locally and wait for response ... local seid 0x%02x, remote seid 0x%02x", avdtp_stream_endpoint_seid(sc.local_stream_endpoint), remote_seid);
535                     a2dp_source_state = A2DP_W4_SET_CONFIGURATION;
536                     avdtp_source_set_configuration(cid, avdtp_stream_endpoint_seid(sc.local_stream_endpoint), remote_seid, sc.local_stream_endpoint->remote_configuration_bitmap, sc.local_stream_endpoint->remote_configuration);
537                     return;
538 
539                 case A2DP_W2_OPEN_STREAM_WITH_SEID:
540                     log_info("A2DP open stream ... local seid 0x%02x, active remote seid 0x%02x", avdtp_stream_endpoint_seid(sc.local_stream_endpoint), sc.local_stream_endpoint->remote_sep.seid);
541                     a2dp_source_state = A2DP_W4_OPEN_STREAM_WITH_SEID;
542                     avdtp_source_open_stream(cid, avdtp_stream_endpoint_seid(sc.local_stream_endpoint), sc.local_stream_endpoint->remote_sep.seid);
543                     break;
544 
545                 case A2DP_W2_RECONFIGURE_WITH_SEID:
546                     log_info("A2DP reconfigured ... local seid 0x%02x, active remote seid 0x%02x", avdtp_stream_endpoint_seid(sc.local_stream_endpoint), sc.local_stream_endpoint->remote_sep.seid);
547                     a2dp_signaling_emit_reconfigured(cid, avdtp_stream_endpoint_seid(sc.local_stream_endpoint), ERROR_CODE_SUCCESS);
548                     a2dp_source_state = A2DP_STREAMING_OPENED;
549                     break;
550 
551                 case A2DP_STREAMING_OPENED:
552                     switch (signal_identifier){
553                         case  AVDTP_SI_START:
554                             a2dp_emit_stream_event(a2dp_source_packet_handler_user, cid, avdtp_stream_endpoint_seid(sc.local_stream_endpoint), A2DP_SUBEVENT_STREAM_STARTED);
555                             break;
556                         case AVDTP_SI_SUSPEND:
557                             a2dp_emit_stream_event(a2dp_source_packet_handler_user, cid, avdtp_stream_endpoint_seid(sc.local_stream_endpoint), A2DP_SUBEVENT_STREAM_SUSPENDED);
558                             break;
559                         case AVDTP_SI_ABORT:
560                         case AVDTP_SI_CLOSE:
561                             a2dp_emit_stream_event(a2dp_source_packet_handler_user, cid, avdtp_stream_endpoint_seid(sc.local_stream_endpoint), A2DP_SUBEVENT_STREAM_STOPPED);
562                             break;
563                         default:
564                             break;
565                     }
566                     break;
567 
568                 default:
569                     break;
570             }
571             break;
572 
573         case AVDTP_SUBEVENT_SIGNALING_REJECT:
574             cid = avdtp_subevent_signaling_reject_get_avdtp_cid(packet);
575             if (a2dp_source_cid != cid) break;
576             if (avdtp_subevent_signaling_reject_get_is_initiator(packet) == 0) break;
577 
578             a2dp_source_state = A2DP_CONNECTED;
579             a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_COMMAND_REJECTED);
580             break;
581 
582         case AVDTP_SUBEVENT_SIGNALING_GENERAL_REJECT:
583             cid = avdtp_subevent_signaling_general_reject_get_avdtp_cid(packet);
584             if (a2dp_source_cid != cid) break;
585             if (avdtp_subevent_signaling_general_reject_get_is_initiator(packet) == 0) break;
586 
587             a2dp_source_state = A2DP_CONNECTED;
588             a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_COMMAND_REJECTED);
589             break;
590 
591         case AVDTP_SUBEVENT_STREAMING_CONNECTION_RELEASED:
592             cid = avdtp_subevent_streaming_connection_released_get_avdtp_cid(packet);
593             if (a2dp_source_cid != cid) break;
594 
595             a2dp_source_state = A2DP_CONFIGURED;
596             a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_STREAM_RELEASED);
597             break;
598 
599         case AVDTP_SUBEVENT_SIGNALING_CONNECTION_RELEASED:
600             cid = avdtp_subevent_signaling_connection_released_get_avdtp_cid(packet);
601             // connect/release are passed on to app
602             if (a2dp_source_cid == cid){
603                 stream_endpoint_configured = false;
604                 a2dp_source_state = A2DP_IDLE;
605                 a2dp_source_cid = 0;
606             }
607             a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_SIGNALING_CONNECTION_RELEASED);
608             break;
609 
610         default:
611             break;
612     }
613 }
614 void a2dp_source_register_packet_handler(btstack_packet_handler_t callback){
615     btstack_assert(callback != NULL);
616 
617     avdtp_source_register_packet_handler(&a2dp_source_packet_handler_internal);
618     a2dp_source_packet_handler_user = callback;
619 }
620 
621 void a2dp_source_init(void){
622     avdtp_source_init();
623 }
624 
625 avdtp_stream_endpoint_t * a2dp_source_create_stream_endpoint(avdtp_media_type_t media_type, avdtp_media_codec_type_t media_codec_type,
626     uint8_t * codec_capabilities, uint16_t codec_capabilities_len,
627     uint8_t * media_codec_info, uint16_t media_codec_info_len){
628     avdtp_stream_endpoint_t * local_stream_endpoint = avdtp_source_create_stream_endpoint(AVDTP_SOURCE, media_type);
629     if (!local_stream_endpoint){
630         return NULL;
631     }
632     avdtp_source_register_media_transport_category(avdtp_stream_endpoint_seid(local_stream_endpoint));
633     avdtp_source_register_media_codec_category(avdtp_stream_endpoint_seid(local_stream_endpoint), media_type, media_codec_type,
634         codec_capabilities, codec_capabilities_len);
635 
636     local_stream_endpoint->remote_configuration.media_codec.media_codec_information     = media_codec_info;
637     local_stream_endpoint->remote_configuration.media_codec.media_codec_information_len = media_codec_info_len;
638     sc.local_stream_endpoint = local_stream_endpoint;
639     avdtp_source_register_delay_reporting_category(avdtp_stream_endpoint_seid(local_stream_endpoint));
640     return local_stream_endpoint;
641 }
642 
643 void a2dp_source_finalize_stream_endpoint(avdtp_stream_endpoint_t * stream_endpoint){
644     avdtp_source_finalize_stream_endpoint(stream_endpoint);
645 }
646 
647 uint8_t a2dp_source_establish_stream(bd_addr_t remote_addr, uint8_t loc_seid, uint16_t * avdtp_cid){
648     if (outgoing_active || stream_endpoint_configured) {
649         return ERROR_CODE_COMMAND_DISALLOWED;
650     }
651 
652     sc.local_stream_endpoint = avdtp_get_stream_endpoint_for_seid(loc_seid);
653     if (!sc.local_stream_endpoint){
654         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
655     }
656 
657     uint16_t outgoing_cid;
658 
659     outgoing_active = true;
660     uint8_t status = avdtp_source_connect(remote_addr, &outgoing_cid);
661     if (status != ERROR_CODE_SUCCESS) {
662         // if there's already a connection for for remote addr, avdtp_source_connect fails,
663         // but the stream will get set-up nevertheless
664         outgoing_active = false;
665         return status;
666     }
667 
668     // stop sep discovery for other
669     if (a2dp_source_state != A2DP_IDLE){
670         avdtp_connection_t * connection = avdtp_get_connection_for_avdtp_cid(a2dp_source_cid);
671         if (connection != NULL){
672             // sdp discovery has started: post-pone action, reserve sep discovery mechanism
673             connection->a2dp_source_discover_seps = true;
674         }
675     }
676 
677     // setup state
678     a2dp_source_state = A2DP_W4_CONNECTED;
679     a2dp_source_cid   = outgoing_cid;
680     *avdtp_cid = outgoing_cid;
681 
682     return ERROR_CODE_SUCCESS;
683 }
684 
685 uint8_t a2dp_source_disconnect(uint16_t avdtp_cid){
686     return avdtp_disconnect(avdtp_cid);
687 }
688 
689 uint8_t a2dp_source_reconfigure_stream_sampling_frequency(uint16_t avdtp_cid, uint32_t sampling_frequency){
690     btstack_assert(sc.local_stream_endpoint != NULL);
691 
692     if (a2dp_source_cid != avdtp_cid){
693         return ERROR_CODE_COMMAND_DISALLOWED;
694     }
695 
696     avdtp_connection_t * connection = avdtp_get_connection_for_avdtp_cid(avdtp_cid);
697     if (connection == NULL){
698         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
699     }
700 
701     if (a2dp_source_state != A2DP_STREAMING_OPENED) {
702         return ERROR_CODE_COMMAND_DISALLOWED;
703     }
704 
705     log_info("Reconfigure avdtp_cid 0x%02x", avdtp_cid);
706 
707     (void)memcpy(sc.local_stream_endpoint->reconfigure_media_codec_sbc_info,
708                  sc.local_stream_endpoint->remote_sep.configuration.media_codec.media_codec_information,
709                  4);
710 
711     // update sampling frequency
712     uint8_t config = sc.local_stream_endpoint->reconfigure_media_codec_sbc_info[0] & 0x0f;
713     switch (sampling_frequency){
714         case 48000:
715             config |= (AVDTP_SBC_48000 << 4);
716             break;
717         case 44100:
718             config |= (AVDTP_SBC_44100 << 4);
719             break;
720         case 32000:
721             config |= (AVDTP_SBC_32000 << 4);
722             break;
723         case 16000:
724             config |= (AVDTP_SBC_16000 << 4);
725             break;
726         default:
727             log_error("Unsupported sampling frequency %u", sampling_frequency);
728             return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
729     }
730     sc.local_stream_endpoint->reconfigure_media_codec_sbc_info[0] = config;
731 
732     avdtp_capabilities_t new_configuration;
733     new_configuration.media_codec.media_type = AVDTP_AUDIO;
734     new_configuration.media_codec.media_codec_type = AVDTP_CODEC_SBC;
735     new_configuration.media_codec.media_codec_information_len = 4;
736     new_configuration.media_codec.media_codec_information = sc.local_stream_endpoint->reconfigure_media_codec_sbc_info;
737 
738     // start reconfigure
739     a2dp_source_state = A2DP_W2_RECONFIGURE_WITH_SEID;
740 
741     return avdtp_source_reconfigure(
742         avdtp_cid,
743         avdtp_stream_endpoint_seid(sc.local_stream_endpoint),
744         sc.local_stream_endpoint->remote_sep.seid,
745         1 << AVDTP_MEDIA_CODEC,
746         new_configuration
747     );
748 }
749 
750 uint8_t a2dp_source_start_stream(uint16_t avdtp_cid, uint8_t local_seid){
751     return avdtp_start_stream(avdtp_cid, local_seid);
752 }
753 
754 uint8_t a2dp_source_pause_stream(uint16_t avdtp_cid, uint8_t local_seid){
755     return avdtp_suspend_stream(avdtp_cid, local_seid);
756 }
757 
758 void a2dp_source_stream_endpoint_request_can_send_now(uint16_t avdtp_cid, uint8_t local_seid){
759     avdtp_source_stream_endpoint_request_can_send_now(avdtp_cid, local_seid);
760 }
761 
762 int a2dp_max_media_payload_size(uint16_t avdtp_cid, uint8_t local_seid){
763     return avdtp_max_media_payload_size(avdtp_cid, local_seid);
764 }
765 
766 int a2dp_source_stream_send_media_payload(uint16_t avdtp_cid, uint8_t local_seid, uint8_t * storage, int num_bytes_to_copy, uint8_t num_frames, uint8_t marker){
767     return avdtp_source_stream_send_media_payload(avdtp_cid, local_seid, storage, num_bytes_to_copy, num_frames, marker);
768 }
769