xref: /btstack/src/classic/a2dp_source.c (revision a512b2289142c4f61455d865a6a0db4f6ce57362)
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_packet_handler_t a2dp_source_packet_handler_user;
73 
74 // config process - singletons using sep_discovery_cid is used as mutex
75 static uint16_t                 sep_discovery_cid;
76 static uint16_t                 sep_discovery_count;
77 static uint16_t                 sep_discovery_index;
78 static avdtp_sep_t              sep_discovery_seps[AVDTP_MAX_SEP_NUM];
79 static btstack_timer_source_t   a2dp_source_set_config_timer;
80 
81 static void a2dp_source_packet_handler_internal(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
82 static void a2dp_discover_seps_with_next_waiting_connection(void);
83 
84 static void a2dp_source_streaming_emit_connection_failed(avdtp_connection_t *connection, uint8_t status) {
85     uint8_t event[14];
86     int pos = 0;
87     event[pos++] = HCI_EVENT_A2DP_META;
88     event[pos++] = sizeof(event) - 2;
89     event[pos++] = A2DP_SUBEVENT_STREAM_ESTABLISHED;
90     little_endian_store_16(event, pos, connection->avdtp_cid);
91     pos += 2;
92     reverse_bd_addr(connection->remote_addr, &event[pos]);
93     pos += 6;
94     event[pos++] = 0;
95     event[pos++] = 0;
96     event[pos++] = status;
97 
98     (*a2dp_source_packet_handler_user)(HCI_EVENT_PACKET, 0, event, sizeof(event));
99 }
100 
101 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){
102     uint8_t* attribute;
103     de_create_sequence(service);
104 
105     // 0x0000 "Service Record Handle"
106     de_add_number(service, DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_SERVICE_RECORD_HANDLE);
107     de_add_number(service, DE_UINT, DE_SIZE_32, service_record_handle);
108 
109     // 0x0001 "Service Class ID List"
110     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_SERVICE_CLASS_ID_LIST);
111     attribute = de_push_sequence(service);
112     {
113         de_add_number(attribute, DE_UUID, DE_SIZE_16, BLUETOOTH_SERVICE_CLASS_AUDIO_SOURCE);
114     }
115     de_pop_sequence(service, attribute);
116 
117     // 0x0004 "Protocol Descriptor List"
118     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_PROTOCOL_DESCRIPTOR_LIST);
119     attribute = de_push_sequence(service);
120     {
121         uint8_t* l2cpProtocol = de_push_sequence(attribute);
122         {
123             de_add_number(l2cpProtocol,  DE_UUID, DE_SIZE_16, BLUETOOTH_PROTOCOL_L2CAP);
124             de_add_number(l2cpProtocol,  DE_UINT, DE_SIZE_16, BLUETOOTH_PSM_AVDTP);
125         }
126         de_pop_sequence(attribute, l2cpProtocol);
127 
128         uint8_t* avProtocol = de_push_sequence(attribute);
129         {
130             de_add_number(avProtocol,  DE_UUID, DE_SIZE_16, BLUETOOTH_PROTOCOL_AVDTP);  // avProtocol_service
131             de_add_number(avProtocol,  DE_UINT, DE_SIZE_16,  0x0103);  // version
132         }
133         de_pop_sequence(attribute, avProtocol);
134     }
135     de_pop_sequence(service, attribute);
136 
137     // 0x0005 "Public Browse Group"
138     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_BROWSE_GROUP_LIST); // public browse group
139     attribute = de_push_sequence(service);
140     {
141         de_add_number(attribute,  DE_UUID, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_PUBLIC_BROWSE_ROOT);
142     }
143     de_pop_sequence(service, attribute);
144 
145     // 0x0009 "Bluetooth Profile Descriptor List"
146     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_BLUETOOTH_PROFILE_DESCRIPTOR_LIST);
147     attribute = de_push_sequence(service);
148     {
149         uint8_t *a2dProfile = de_push_sequence(attribute);
150         {
151             de_add_number(a2dProfile,  DE_UUID, DE_SIZE_16, BLUETOOTH_SERVICE_CLASS_ADVANCED_AUDIO_DISTRIBUTION);
152             de_add_number(a2dProfile,  DE_UINT, DE_SIZE_16, 0x0103);
153         }
154         de_pop_sequence(attribute, a2dProfile);
155     }
156     de_pop_sequence(service, attribute);
157 
158 
159     // 0x0100 "Service Name"
160     de_add_number(service,  DE_UINT, DE_SIZE_16, 0x0100);
161     if (service_name){
162         de_add_data(service,  DE_STRING, strlen(service_name), (uint8_t *) service_name);
163     } else {
164         de_add_data(service,  DE_STRING, strlen(default_a2dp_source_service_name), (uint8_t *) default_a2dp_source_service_name);
165     }
166 
167     // 0x0100 "Provider Name"
168     de_add_number(service,  DE_UINT, DE_SIZE_16, 0x0102);
169     if (service_provider_name){
170         de_add_data(service,  DE_STRING, strlen(service_provider_name), (uint8_t *) service_provider_name);
171     } else {
172         de_add_data(service,  DE_STRING, strlen(default_a2dp_source_service_provider_name), (uint8_t *) default_a2dp_source_service_provider_name);
173     }
174 
175     // 0x0311 "Supported Features"
176     de_add_number(service, DE_UINT, DE_SIZE_16, 0x0311);
177     de_add_number(service, DE_UINT, DE_SIZE_16, supported_features);
178 }
179 
180 static void a2dp_signaling_emit_reconfigured(uint16_t cid, uint8_t local_seid, uint8_t status){
181     uint8_t event[7];
182     int pos = 0;
183     event[pos++] = HCI_EVENT_A2DP_META;
184     event[pos++] = sizeof(event) - 2;
185     event[pos++] = A2DP_SUBEVENT_STREAM_RECONFIGURED;
186     little_endian_store_16(event, pos, cid);
187     pos += 2;
188     event[pos++] = local_seid;
189     event[pos++] = status;
190     (*a2dp_source_packet_handler_user)(HCI_EVENT_PACKET, 0, event, sizeof(event));
191 }
192 
193 static void a2dp_source_set_config_timer_handler(btstack_timer_source_t * timer){
194     uint16_t avdtp_cid = (uint16_t)(uintptr_t) btstack_run_loop_get_timer_context(timer);
195 	avdtp_connection_t * connection = avdtp_get_connection_for_avdtp_cid(avdtp_cid);
196 	btstack_run_loop_set_timer_context(&a2dp_source_set_config_timer, NULL);
197 
198     if (connection == NULL) {
199         log_info("a2dp_discover_seps_with_next_waiting_connection");
200         a2dp_discover_seps_with_next_waiting_connection();
201         return;
202     }
203 
204     if (connection->a2dp_source_stream_endpoint_configured) return;
205     avdtp_source_discover_stream_endpoints(avdtp_cid);
206 }
207 
208 static void a2dp_source_set_config_timer_start(uint16_t avdtp_cid){
209     log_info("a2dp_source_set_config_timer_start cid 0%02x", avdtp_cid);
210     btstack_run_loop_remove_timer(&a2dp_source_set_config_timer);
211     btstack_run_loop_set_timer_handler(&a2dp_source_set_config_timer,a2dp_source_set_config_timer_handler);
212     btstack_run_loop_set_timer(&a2dp_source_set_config_timer, A2DP_SET_CONFIG_DELAY_MS);
213     btstack_run_loop_set_timer_context(&a2dp_source_set_config_timer, (void *)(uintptr_t)avdtp_cid);
214     btstack_run_loop_add_timer(&a2dp_source_set_config_timer);
215 }
216 
217 static void a2dp_source_set_config_timer_stop(void){
218     log_info("a2dp_source_set_config_timer_stop");
219     btstack_run_loop_remove_timer(&a2dp_source_set_config_timer);
220 	btstack_run_loop_set_timer_context(&a2dp_source_set_config_timer, NULL);
221 }
222 
223 // Discover seps, both incoming and outgoing
224 static void a2dp_start_discovering_seps(avdtp_connection_t * connection){
225     connection->a2dp_source_state = A2DP_DISCOVER_SEPS;
226     connection->a2dp_source_discover_seps = false;
227 
228     sep_discovery_index = 0;
229     sep_discovery_count = 0;
230     memset(sep_discovery_seps, 0, sizeof(avdtp_sep_t) * AVDTP_MAX_SEP_NUM);
231     sep_discovery_cid = connection->avdtp_cid;
232 
233     // if we initiated the connection, start config right away, else wait a bit to give remote a chance to do it first
234     if (connection->a2dp_source_outgoing_active){
235         log_info("discover seps");
236         avdtp_source_discover_stream_endpoints(connection->avdtp_cid);
237     } else {
238         log_info("wait a bit, then discover seps");
239         a2dp_source_set_config_timer_start(connection->avdtp_cid);
240     }
241 }
242 
243 static void a2dp_discover_seps_with_next_waiting_connection(void){
244     btstack_assert(sep_discovery_cid == 0);
245     btstack_linked_list_iterator_t it;
246     btstack_linked_list_iterator_init(&it, avdtp_get_connections());
247     while (btstack_linked_list_iterator_has_next(&it)){
248         avdtp_connection_t * next_connection = (avdtp_connection_t *)btstack_linked_list_iterator_next(&it);
249         if (!next_connection->a2dp_source_discover_seps) continue;
250         a2dp_start_discovering_seps(next_connection);
251     }
252 }
253 
254 static void a2dp_source_ready_for_sep_discovery(avdtp_connection_t * connection){
255     // start discover seps now if:
256     // - outgoing active: signaling for outgoing connection
257     // - outgoing not active: incoming connection and no sep discover ongoing
258 
259     // sep discovery active?
260     if (sep_discovery_cid == 0){
261         a2dp_start_discovering_seps(connection);
262     } else {
263         // post-pone sep discovery
264         connection->a2dp_source_discover_seps = true;
265     }
266 }
267 
268 static void a2dp_handle_received_configuration(const uint8_t *packet, uint8_t local_seid) {
269     uint16_t cid = avdtp_subevent_signaling_media_codec_sbc_configuration_get_avdtp_cid(packet);
270     avdtp_connection_t *avdtp_connection = avdtp_get_connection_for_avdtp_cid(cid);
271     btstack_assert(avdtp_connection != NULL);
272     avdtp_connection->a2dp_source_local_stream_endpoint = avdtp_get_stream_endpoint_for_seid(local_seid);
273     // bail out if local seid invalid
274     if (!avdtp_connection->a2dp_source_local_stream_endpoint) return;
275 
276     // stop timer
277     if (sep_discovery_cid == cid) {
278         a2dp_source_set_config_timer_stop();
279         sep_discovery_cid = 0;
280     }
281 
282     avdtp_connection->a2dp_source_stream_endpoint_configured = true;
283 
284     switch (avdtp_connection->a2dp_source_state) {
285         case A2DP_W4_SET_CONFIGURATION:
286             // outgoing: discovery and config of remote sink sep successful, trigger stream open
287             avdtp_connection->a2dp_source_state = A2DP_W2_OPEN_STREAM_WITH_SEID;
288             break;
289         case A2DP_DISCOVER_SEPS:
290         case A2DP_GET_CAPABILITIES:
291         case A2DP_W2_GET_ALL_CAPABILITIES:
292         case A2DP_DISCOVERY_DONE:
293         case A2DP_W4_GET_CONFIGURATION:
294             // incoming: wait for stream open
295             avdtp_connection->a2dp_source_state = A2DP_W4_OPEN_STREAM_WITH_SEID;
296             break;
297         default:
298             // wait for configuration after sending reconfigure - keep state
299             break;
300     }
301 }
302 
303 static void a2dp_source_set_config(avdtp_connection_t * connection){
304     uint8_t remote_seid = connection->a2dp_source_local_stream_endpoint->set_config_remote_seid;
305     log_info("A2DP initiate set configuration locally and wait for response ... local seid 0x%02x, remote seid 0x%02x", avdtp_stream_endpoint_seid(connection->a2dp_source_local_stream_endpoint), remote_seid);
306     connection->a2dp_source_state = A2DP_W4_SET_CONFIGURATION;
307     avdtp_source_set_configuration(connection->avdtp_cid, avdtp_stream_endpoint_seid(connection->a2dp_source_local_stream_endpoint), remote_seid, connection->a2dp_source_local_stream_endpoint->remote_configuration_bitmap, connection->a2dp_source_local_stream_endpoint->remote_configuration);
308 }
309 
310 static void a2dp_source_packet_handler_internal(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
311     UNUSED(channel);
312     UNUSED(size);
313 
314     uint16_t cid;
315     avdtp_connection_t * connection;
316 
317     uint8_t signal_identifier;
318     uint8_t status;
319     uint8_t local_seid;
320     uint8_t remote_seid;
321 
322     if (packet_type != HCI_EVENT_PACKET) return;
323     if (hci_event_packet_get_type(packet) != HCI_EVENT_AVDTP_META) return;
324 
325     switch (packet[2]){
326         case AVDTP_SUBEVENT_SIGNALING_CONNECTION_ESTABLISHED:
327             cid = avdtp_subevent_signaling_connection_established_get_avdtp_cid(packet);
328             connection = avdtp_get_connection_for_avdtp_cid(cid);
329             btstack_assert(connection != NULL);
330 
331             status = avdtp_subevent_signaling_connection_established_get_status(packet);
332             if (status != ERROR_CODE_SUCCESS){
333                 // notify about connection error only if we're initiator
334                 if (connection->a2dp_source_outgoing_active){
335                     log_info("A2DP source signaling connection failed status 0x%02x", status);
336                     connection->a2dp_source_outgoing_active = false;
337                     a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_SIGNALING_CONNECTION_ESTABLISHED);
338                 }
339                 break;
340             }
341             log_info("A2DP source signaling connection established avdtp_cid 0x%02x", cid);
342             connection->a2dp_source_state = A2DP_CONNECTED;
343 
344             // notify app
345             a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_SIGNALING_CONNECTION_ESTABLISHED);
346 
347             // continue
348             a2dp_source_ready_for_sep_discovery(connection);
349             break;
350 
351         case AVDTP_SUBEVENT_SIGNALING_SEP_FOUND:
352             cid = avdtp_subevent_signaling_sep_found_get_avdtp_cid(packet);
353             connection = avdtp_get_connection_for_avdtp_cid(cid);
354             btstack_assert(connection != NULL);
355 
356             if (connection->a2dp_source_state == A2DP_DISCOVER_SEPS) {
357                 avdtp_sep_t sep;
358                 memset(&sep, 0, sizeof(avdtp_sep_t));
359                 sep.seid       = avdtp_subevent_signaling_sep_found_get_remote_seid(packet);;
360                 sep.in_use     = avdtp_subevent_signaling_sep_found_get_in_use(packet);
361                 sep.media_type = (avdtp_media_type_t) avdtp_subevent_signaling_sep_found_get_media_type(packet);
362                 sep.type       = (avdtp_sep_type_t) avdtp_subevent_signaling_sep_found_get_sep_type(packet);
363                 log_info("A2DP Found sep: remote seid 0x%02x, in_use %d, media type %d, sep type %s, index %d",
364                          sep.seid, sep.in_use, sep.media_type, sep.type == AVDTP_SOURCE ? "source" : "sink",
365                          sep_discovery_count);
366                 if ((sep.type == AVDTP_SINK) && (sep.in_use == false)) {
367                     sep_discovery_seps[sep_discovery_count++] = sep;
368                 }
369             }
370             break;
371 
372         case AVDTP_SUBEVENT_SIGNALING_SEP_DICOVERY_DONE:
373             cid = avdtp_subevent_signaling_sep_dicovery_done_get_avdtp_cid(packet);
374             connection = avdtp_get_connection_for_avdtp_cid(cid);
375             btstack_assert(connection != NULL);
376 
377             if (connection->a2dp_source_state != A2DP_DISCOVER_SEPS) break;
378 
379             if (sep_discovery_count > 0){
380                 connection->a2dp_source_state = A2DP_GET_CAPABILITIES;
381                 sep_discovery_index = 0;
382                 connection->a2dp_source_have_config = false;
383             } else {
384                 if (connection->a2dp_source_outgoing_active){
385                     connection->a2dp_source_outgoing_active = false;
386                     connection = avdtp_get_connection_for_avdtp_cid(cid);
387                     btstack_assert(connection != NULL);
388                     a2dp_source_streaming_emit_connection_failed(connection, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_NO_SUITABLE_CHANNEL_FOUND);
389                 }
390 
391                 // continue
392                 connection->a2dp_source_state = A2DP_CONNECTED;
393                 sep_discovery_cid = 0;
394                 a2dp_discover_seps_with_next_waiting_connection();
395             }
396             break;
397 
398         case AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CAPABILITY:
399             cid = avdtp_subevent_signaling_media_codec_sbc_capability_get_avdtp_cid(packet);
400             connection = avdtp_get_connection_for_avdtp_cid(cid);
401             btstack_assert(connection != NULL);
402 
403             if (connection->a2dp_source_state != A2DP_GET_CAPABILITIES) break;
404 
405             // forward codec capability
406             a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CAPABILITY);
407 
408 #ifndef ENABLE_A2DP_SOURCE_EXPLICIT_CONFIG
409             // select SEP if none configured yet
410             if (connection->a2dp_source_have_config == false){
411                 // find SBC stream endpoint
412                 avdtp_stream_endpoint_t * stream_endpoint = avdtp_get_source_stream_endpoint_for_media_codec(AVDTP_CODEC_SBC);
413                 if (stream_endpoint != NULL){
414                     // choose SBC config params
415                     avdtp_configuration_sbc_t configuration;
416                     configuration.sampling_frequency = avdtp_choose_sbc_sampling_frequency(stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_sampling_frequency_bitmap(packet));
417                     configuration.channel_mode       = avdtp_choose_sbc_channel_mode(stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_channel_mode_bitmap(packet));
418                     configuration.block_length       = avdtp_choose_sbc_block_length(stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_block_length_bitmap(packet));
419                     configuration.subbands           = avdtp_choose_sbc_subbands(stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_subbands_bitmap(packet));
420                     configuration.allocation_method  = avdtp_choose_sbc_allocation_method(stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_allocation_method_bitmap(packet));
421                     configuration.max_bitpool_value  = avdtp_choose_sbc_max_bitpool_value(stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_max_bitpool_value(packet));
422                     configuration.min_bitpool_value  = avdtp_choose_sbc_min_bitpool_value(stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_min_bitpool_value(packet));
423 
424                     // and pre-select this endpoint
425                     local_seid = avdtp_stream_endpoint_seid(stream_endpoint);
426                     remote_seid = avdtp_subevent_signaling_media_codec_sbc_capability_get_remote_seid(packet);
427                     a2dp_source_set_config_sbc(cid, local_seid, remote_seid, &configuration);
428                 }
429             }
430 #endif
431             break;
432 
433         // forward codec capability
434         case AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_MPEG_AUDIO_CAPABILITY:
435             cid = avdtp_subevent_signaling_media_codec_mpeg_audio_capability_get_avdtp_cid(packet);
436             connection = avdtp_get_connection_for_avdtp_cid(cid);
437             btstack_assert(connection != NULL);
438 
439             if (connection->a2dp_source_state != A2DP_GET_CAPABILITIES) break;
440             a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_SIGNALING_MEDIA_CODEC_MPEG_AUDIO_CAPABILITY);
441             break;
442         case AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_MPEG_AAC_CAPABILITY:
443             cid = avdtp_subevent_signaling_media_codec_mpeg_aac_capability_get_avdtp_cid(packet);
444             connection = avdtp_get_connection_for_avdtp_cid(cid);
445             btstack_assert(connection != NULL);
446 
447             if (connection->a2dp_source_state != A2DP_GET_CAPABILITIES) break;
448             a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_SIGNALING_MEDIA_CODEC_MPEG_AAC_CAPABILITY);
449             break;
450         case AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_ATRAC_CAPABILITY:
451             cid = avdtp_subevent_signaling_media_codec_atrac_capability_get_avdtp_cid(packet);
452             connection = avdtp_get_connection_for_avdtp_cid(cid);
453             btstack_assert(connection != NULL);
454 
455             if (connection->a2dp_source_state != A2DP_GET_CAPABILITIES) break;
456             a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_SIGNALING_MEDIA_CODEC_ATRAC_CAPABILITY);
457             break;
458         case AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_OTHER_CAPABILITY:
459             cid = avdtp_subevent_signaling_media_codec_other_capability_get_avdtp_cid(packet);
460             connection = avdtp_get_connection_for_avdtp_cid(cid);
461             btstack_assert(connection != NULL);
462 
463             if (connection->a2dp_source_state != A2DP_GET_CAPABILITIES) break;
464             a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_SIGNALING_MEDIA_CODEC_OTHER_CAPABILITY);
465             break;
466 
467         // not forwarded
468         case AVDTP_SUBEVENT_SIGNALING_MEDIA_TRANSPORT_CAPABILITY:
469         case AVDTP_SUBEVENT_SIGNALING_REPORTING_CAPABILITY:
470         case AVDTP_SUBEVENT_SIGNALING_RECOVERY_CAPABILITY:
471         case AVDTP_SUBEVENT_SIGNALING_CONTENT_PROTECTION_CAPABILITY:
472         case AVDTP_SUBEVENT_SIGNALING_HEADER_COMPRESSION_CAPABILITY:
473         case AVDTP_SUBEVENT_SIGNALING_MULTIPLEXING_CAPABILITY:
474             break;
475 
476         case AVDTP_SUBEVENT_SIGNALING_DELAY_REPORTING_CAPABILITY:
477             cid = avdtp_subevent_signaling_delay_reporting_capability_get_avdtp_cid(packet);
478             connection = avdtp_get_connection_for_avdtp_cid(cid);
479             btstack_assert(connection != NULL);
480             log_info("received AVDTP_SUBEVENT_SIGNALING_DELAY_REPORTING_CAPABILITY, cid 0x%02x, state %d", cid, connection->a2dp_source_state);
481 
482             if (connection->a2dp_source_state != A2DP_GET_CAPABILITIES) break;
483 
484             // store delay reporting capability
485             sep_discovery_seps[sep_discovery_index].registered_service_categories |= 1 << AVDTP_DELAY_REPORTING;
486 
487             a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_SIGNALING_DELAY_REPORTING_CAPABILITY);
488             break;
489 
490         case AVDTP_SUBEVENT_SIGNALING_CAPABILITIES_DONE:
491             cid = avdtp_subevent_signaling_capabilities_done_get_avdtp_cid(packet);
492             connection = avdtp_get_connection_for_avdtp_cid(cid);
493             btstack_assert(connection != NULL);
494 
495             if (connection->a2dp_source_state != A2DP_GET_CAPABILITIES) break;
496 
497             // forward capabilities done for endpoint
498             a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_SIGNALING_CAPABILITIES_DONE);
499 
500             // endpoint was not suitable, check next one
501             sep_discovery_index++;
502             if (sep_discovery_index >= sep_discovery_count){
503 
504                 // emit 'all capabilities for all seps reported'
505                 uint8_t event[6];
506                 uint8_t pos = 0;
507                 event[pos++] = HCI_EVENT_A2DP_META;
508                 event[pos++] = sizeof(event) - 2;
509                 event[pos++] = A2DP_SUBEVENT_SIGNALING_CAPABILITIES_COMPLETE;
510                 little_endian_store_16(event, pos, cid);
511                 (*a2dp_source_packet_handler_user)(HCI_EVENT_PACKET, 0, event, sizeof(event));
512 
513                 // do we have a valid config?
514                 if (connection->a2dp_source_have_config){
515                     connection->a2dp_source_state = A2DP_SET_CONFIGURATION;
516                     connection->a2dp_source_have_config = false;
517                     break;
518                 }
519 
520 #ifdef ENABLE_A2DP_SOURCE_EXPLICIT_CONFIG
521                 connection->a2dp_source_state = A2DP_DISCOVERY_DONE;
522                 // TODO call a2dp_discover_seps_with_next_waiting_connection?
523                 break;
524 #else
525                 // we didn't find a suitable SBC stream endpoint, sorry.
526                 if (connection->a2dp_source_outgoing_active){
527                     connection->a2dp_source_outgoing_active = false;
528                     connection = avdtp_get_connection_for_avdtp_cid(cid);
529                     btstack_assert(connection != NULL);
530                     a2dp_source_streaming_emit_connection_failed(connection, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_NO_SUITABLE_CHANNEL_FOUND);
531                 }
532                 connection->a2dp_source_state = A2DP_CONNECTED;
533                 sep_discovery_cid = 0;
534                 a2dp_discover_seps_with_next_waiting_connection();
535 #endif
536             }
537             break;
538 
539         case AVDTP_SUBEVENT_SIGNALING_DELAY_REPORT:
540             cid = avdtp_subevent_signaling_delay_report_get_avdtp_cid(packet);
541             connection = avdtp_get_connection_for_avdtp_cid(cid);
542             btstack_assert(connection != NULL);
543 
544             a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_SIGNALING_DELAY_REPORT);
545             break;
546 
547             // forward codec configuration
548         case AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CONFIGURATION:
549             local_seid = avdtp_subevent_signaling_media_codec_sbc_configuration_get_local_seid(packet);
550             a2dp_handle_received_configuration(packet, local_seid);
551             a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CONFIGURATION);
552             break;
553         case AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_MPEG_AUDIO_CONFIGURATION:
554             local_seid = avdtp_subevent_signaling_media_codec_mpeg_audio_configuration_get_local_seid(packet);
555             a2dp_handle_received_configuration(packet, local_seid);
556             a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_SIGNALING_MEDIA_CODEC_MPEG_AUDIO_CONFIGURATION);
557             break;
558         case AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_MPEG_AAC_CONFIGURATION:
559             local_seid = avdtp_subevent_signaling_media_codec_mpeg_aac_configuration_get_local_seid(packet);
560             a2dp_handle_received_configuration(packet, local_seid);
561             a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_SIGNALING_MEDIA_CODEC_MPEG_AAC_CONFIGURATION);
562             break;
563         case AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_ATRAC_CONFIGURATION:
564             local_seid = avdtp_subevent_signaling_media_codec_atrac_configuration_get_local_seid(packet);
565             a2dp_handle_received_configuration(packet, local_seid);
566             a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_SIGNALING_MEDIA_CODEC_ATRAC_CONFIGURATION);
567             break;
568         case AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_OTHER_CONFIGURATION:
569             local_seid = avdtp_subevent_signaling_media_codec_sbc_configuration_get_local_seid(packet);
570             a2dp_handle_received_configuration(packet, local_seid);
571             a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_SIGNALING_MEDIA_CODEC_OTHER_CONFIGURATION);
572             break;
573 
574         case AVDTP_SUBEVENT_STREAMING_CAN_SEND_MEDIA_PACKET_NOW:
575             a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_STREAMING_CAN_SEND_MEDIA_PACKET_NOW);
576             break;
577 
578         case AVDTP_SUBEVENT_STREAMING_CONNECTION_ESTABLISHED:
579             cid = avdtp_subevent_streaming_connection_established_get_avdtp_cid(packet);
580             connection = avdtp_get_connection_for_avdtp_cid(cid);
581             btstack_assert(connection != NULL);
582 
583             if (connection->a2dp_source_state != A2DP_W4_OPEN_STREAM_WITH_SEID) break;
584 
585             connection->a2dp_source_outgoing_active = false;
586             status = avdtp_subevent_streaming_connection_established_get_status(packet);
587             if (status != ERROR_CODE_SUCCESS){
588                 log_info("A2DP source streaming connection could not be established, avdtp_cid 0x%02x, status 0x%02x ---", cid, status);
589                 a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_STREAM_ESTABLISHED);
590                 break;
591             }
592 
593             log_info("A2DP source streaming connection established --- avdtp_cid 0x%02x, local seid 0x%02x, remote seid 0x%02x", cid,
594                 avdtp_subevent_streaming_connection_established_get_local_seid(packet),
595                 avdtp_subevent_streaming_connection_established_get_remote_seid(packet));
596             connection->a2dp_source_state = A2DP_STREAMING_OPENED;
597             a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_STREAM_ESTABLISHED);
598             break;
599 
600         case AVDTP_SUBEVENT_SIGNALING_ACCEPT:
601             cid = avdtp_subevent_signaling_accept_get_avdtp_cid(packet);
602             connection = avdtp_get_connection_for_avdtp_cid(cid);
603             btstack_assert(connection != NULL);
604 
605 			// reset discovery timer while remote is active for current cid
606 			if ((avdtp_subevent_signaling_accept_get_is_initiator(packet) == 0) && (cid == sep_discovery_cid)){
607 				log_info("Reset discovery timer");
608 				a2dp_source_set_config_timer_start(sep_discovery_cid);
609 				break;
610 			}
611 
612             signal_identifier = avdtp_subevent_signaling_accept_get_signal_identifier(packet);
613 
614             log_info("A2DP cmd %s accepted, global state %d, cid 0x%02x", avdtp_si2str(signal_identifier), connection->a2dp_source_state, cid);
615 
616             switch (connection->a2dp_source_state){
617                 case A2DP_GET_CAPABILITIES:
618                     remote_seid = sep_discovery_seps[sep_discovery_index].seid;
619                     log_info("A2DP get capabilities for remote seid 0x%02x", remote_seid);
620                     avdtp_source_get_all_capabilities(cid, remote_seid);
621                     return;
622 
623                 case A2DP_SET_CONFIGURATION:
624                     a2dp_source_set_config(connection);
625                     return;
626 
627                 case A2DP_W2_OPEN_STREAM_WITH_SEID:
628                     log_info("A2DP open stream ... local seid 0x%02x, active remote seid 0x%02x", avdtp_stream_endpoint_seid(connection->a2dp_source_local_stream_endpoint), connection->a2dp_source_local_stream_endpoint->remote_sep.seid);
629                     connection->a2dp_source_state = A2DP_W4_OPEN_STREAM_WITH_SEID;
630                     avdtp_source_open_stream(cid, avdtp_stream_endpoint_seid(connection->a2dp_source_local_stream_endpoint), connection->a2dp_source_local_stream_endpoint->remote_sep.seid);
631                     break;
632 
633                 case A2DP_W2_RECONFIGURE_WITH_SEID:
634                     log_info("A2DP reconfigured ... local seid 0x%02x, active remote seid 0x%02x", avdtp_stream_endpoint_seid(connection->a2dp_source_local_stream_endpoint), connection->a2dp_source_local_stream_endpoint->remote_sep.seid);
635                     a2dp_signaling_emit_reconfigured(cid, avdtp_stream_endpoint_seid(connection->a2dp_source_local_stream_endpoint), ERROR_CODE_SUCCESS);
636                     connection->a2dp_source_state = A2DP_STREAMING_OPENED;
637                     break;
638 
639                 case A2DP_STREAMING_OPENED:
640                     switch (signal_identifier){
641                         case  AVDTP_SI_START:
642                             a2dp_emit_stream_event(a2dp_source_packet_handler_user, cid, avdtp_stream_endpoint_seid(connection->a2dp_source_local_stream_endpoint), A2DP_SUBEVENT_STREAM_STARTED);
643                             break;
644                         case AVDTP_SI_SUSPEND:
645                             a2dp_emit_stream_event(a2dp_source_packet_handler_user, cid, avdtp_stream_endpoint_seid(connection->a2dp_source_local_stream_endpoint), A2DP_SUBEVENT_STREAM_SUSPENDED);
646                             break;
647                         case AVDTP_SI_ABORT:
648                         case AVDTP_SI_CLOSE:
649                             a2dp_emit_stream_event(a2dp_source_packet_handler_user, cid, avdtp_stream_endpoint_seid(connection->a2dp_source_local_stream_endpoint), A2DP_SUBEVENT_STREAM_STOPPED);
650                             break;
651                         default:
652                             break;
653                     }
654                     break;
655 
656                 default:
657                     break;
658             }
659             break;
660 
661         case AVDTP_SUBEVENT_SIGNALING_REJECT:
662             cid = avdtp_subevent_signaling_reject_get_avdtp_cid(packet);
663             connection = avdtp_get_connection_for_avdtp_cid(cid);
664             btstack_assert(connection != NULL);
665 
666             if (avdtp_subevent_signaling_reject_get_is_initiator(packet) == 0) break;
667 
668             switch (connection->a2dp_source_state) {
669                 case A2DP_W2_RECONFIGURE_WITH_SEID:
670                     log_info("A2DP reconfigure failed ... local seid 0x%02x, active remote seid 0x%02x", avdtp_stream_endpoint_seid(connection->a2dp_source_local_stream_endpoint), connection->a2dp_source_local_stream_endpoint->remote_sep.seid);
671                     a2dp_signaling_emit_reconfigured(cid, avdtp_stream_endpoint_seid(connection->a2dp_source_local_stream_endpoint), ERROR_CODE_UNSPECIFIED_ERROR);
672                     connection->a2dp_source_state = A2DP_STREAMING_OPENED;
673                     break;
674                 default:
675                     connection->a2dp_source_state = A2DP_CONNECTED;
676                     break;
677             }
678 
679             a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_COMMAND_REJECTED);
680             break;
681 
682         case AVDTP_SUBEVENT_SIGNALING_GENERAL_REJECT:
683             cid = avdtp_subevent_signaling_general_reject_get_avdtp_cid(packet);
684             connection = avdtp_get_connection_for_avdtp_cid(cid);
685             btstack_assert(connection != NULL);
686 
687             if (avdtp_subevent_signaling_general_reject_get_is_initiator(packet) == 0) break;
688 
689             connection->a2dp_source_state = A2DP_CONNECTED;
690             a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_COMMAND_REJECTED);
691             break;
692 
693         case AVDTP_SUBEVENT_STREAMING_CONNECTION_RELEASED:
694             cid = avdtp_subevent_streaming_connection_released_get_avdtp_cid(packet);
695             connection = avdtp_get_connection_for_avdtp_cid(cid);
696             btstack_assert(connection != NULL);
697 
698             connection->a2dp_source_state = A2DP_CONFIGURED;
699             a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_STREAM_RELEASED);
700             break;
701 
702         case AVDTP_SUBEVENT_SIGNALING_CONNECTION_RELEASED:
703             cid = avdtp_subevent_signaling_connection_released_get_avdtp_cid(packet);
704             connection = avdtp_get_connection_for_avdtp_cid(cid);
705             btstack_assert(connection != NULL);
706 
707             // connect/release are passed on to app
708             if (sep_discovery_cid == cid){
709                 a2dp_source_set_config_timer_stop();
710                 connection->a2dp_source_stream_endpoint_configured = false;
711                 connection->a2dp_source_local_stream_endpoint = NULL;
712 
713                 connection->a2dp_source_state = A2DP_IDLE;
714                 sep_discovery_cid = 0;
715             }
716             a2dp_replace_subevent_id_and_emit_cmd(a2dp_source_packet_handler_user, packet, size, A2DP_SUBEVENT_SIGNALING_CONNECTION_RELEASED);
717             break;
718 
719         default:
720             break;
721     }
722 }
723 void a2dp_source_register_packet_handler(btstack_packet_handler_t callback){
724     btstack_assert(callback != NULL);
725 
726     avdtp_source_register_packet_handler(&a2dp_source_packet_handler_internal);
727     a2dp_source_packet_handler_user = callback;
728 }
729 
730 void a2dp_source_init(void){
731     avdtp_source_init();
732 }
733 
734 void a2dp_source_deinit(void){
735     avdtp_source_deinit();
736     sep_discovery_count = 0;
737 }
738 
739 avdtp_stream_endpoint_t * a2dp_source_create_stream_endpoint(avdtp_media_type_t media_type, avdtp_media_codec_type_t media_codec_type,
740                                                              const uint8_t *codec_capabilities, uint16_t codec_capabilities_len,
741                                                              uint8_t * codec_configuration, uint16_t codec_configuration_len){
742     avdtp_stream_endpoint_t * stream_endpoint = avdtp_source_create_stream_endpoint(AVDTP_SOURCE, media_type);
743     if (!stream_endpoint){
744         return NULL;
745     }
746     avdtp_source_register_media_transport_category(avdtp_stream_endpoint_seid(stream_endpoint));
747     avdtp_source_register_media_codec_category(avdtp_stream_endpoint_seid(stream_endpoint), media_type, media_codec_type,
748                                                codec_capabilities, codec_capabilities_len);
749 	avdtp_source_register_delay_reporting_category(avdtp_stream_endpoint_seid(stream_endpoint));
750 
751 	// store user codec configuration buffer
752 	stream_endpoint->media_codec_type = media_codec_type;
753 	stream_endpoint->media_codec_configuration_info = codec_configuration;
754     stream_endpoint->media_codec_configuration_len  = codec_configuration_len;
755 
756     return stream_endpoint;
757 }
758 
759 void a2dp_source_finalize_stream_endpoint(avdtp_stream_endpoint_t * stream_endpoint){
760     avdtp_source_finalize_stream_endpoint(stream_endpoint);
761 }
762 
763 uint8_t a2dp_source_establish_stream(bd_addr_t remote_addr, uint16_t *avdtp_cid) {
764 
765     uint16_t outgoing_cid;
766 
767     avdtp_connection_t * connection = avdtp_get_connection_for_bd_addr(remote_addr);
768     if (connection == NULL){
769         uint8_t status = avdtp_source_connect(remote_addr, &outgoing_cid);
770         if (status != ERROR_CODE_SUCCESS) {
771             // if there's already a connection for for remote addr, avdtp_source_connect fails,
772             // but the stream will get set-up nevertheless
773             return status;
774         }
775         connection = avdtp_get_connection_for_avdtp_cid(outgoing_cid);
776         btstack_assert(connection != NULL);
777 
778         // setup state
779         connection->a2dp_source_outgoing_active = true;
780         connection->a2dp_source_state = A2DP_W4_CONNECTED;
781         *avdtp_cid = outgoing_cid;
782 
783     } else {
784         if (connection->a2dp_source_outgoing_active || connection->a2dp_source_stream_endpoint_configured) {
785             return ERROR_CODE_COMMAND_DISALLOWED;
786         }
787 
788         // check state
789         switch (connection->a2dp_source_state){
790             case A2DP_IDLE:
791             case A2DP_CONNECTED:
792                 // restart process e.g. if there no suitable stream endpoints or they had been in use
793                 connection->a2dp_source_outgoing_active = true;
794                 *avdtp_cid = connection->avdtp_cid;
795                 a2dp_source_ready_for_sep_discovery(connection);
796                 break;
797             default:
798                 return ERROR_CODE_COMMAND_DISALLOWED;
799         }
800     }
801     return ERROR_CODE_SUCCESS;
802 }
803 
804 uint8_t a2dp_source_disconnect(uint16_t avdtp_cid){
805     return avdtp_disconnect(avdtp_cid);
806 }
807 
808 
809 uint8_t a2dp_source_start_stream(uint16_t avdtp_cid, uint8_t local_seid){
810     return avdtp_start_stream(avdtp_cid, local_seid);
811 }
812 
813 uint8_t a2dp_source_pause_stream(uint16_t avdtp_cid, uint8_t local_seid){
814     return avdtp_suspend_stream(avdtp_cid, local_seid);
815 }
816 
817 void a2dp_source_stream_endpoint_request_can_send_now(uint16_t avdtp_cid, uint8_t local_seid){
818     avdtp_source_stream_endpoint_request_can_send_now(avdtp_cid, local_seid);
819 }
820 
821 int a2dp_max_media_payload_size(uint16_t avdtp_cid, uint8_t local_seid){
822     return avdtp_max_media_payload_size(avdtp_cid, local_seid);
823 }
824 
825 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){
826     return avdtp_source_stream_send_media_payload(avdtp_cid, local_seid, storage, num_bytes_to_copy, num_frames, marker);
827 }
828 
829 uint8_t a2dp_source_stream_send_media_payload_rtp(uint16_t a2dp_cid, uint8_t local_seid, uint8_t marker, uint8_t * payload, uint16_t payload_size){
830     return avdtp_source_stream_send_media_payload_rtp(a2dp_cid, local_seid, marker, payload, payload_size);
831 }
832 
833 uint8_t	a2dp_source_stream_send_media_packet(uint16_t a2dp_cid, uint8_t local_seid, const uint8_t * packet, uint16_t size){
834     return avdtp_source_stream_send_media_packet(a2dp_cid, local_seid, packet, size);
835 }
836 
837 static uint8_t a2dp_source_config_init(avdtp_connection_t *connection, uint8_t local_seid, uint8_t remote_seid,
838                                        avdtp_media_codec_type_t codec_type) {
839 
840     // check state
841     switch (connection->a2dp_source_state){
842         case A2DP_DISCOVERY_DONE:
843         case A2DP_GET_CAPABILITIES:
844             break;
845         default:
846             return ERROR_CODE_COMMAND_DISALLOWED;
847     }
848 
849     // lookup local stream endpoint
850     avdtp_stream_endpoint_t * stream_endpoint = avdtp_get_stream_endpoint_for_seid(local_seid);
851     if (stream_endpoint == NULL){
852         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
853     }
854 
855     // lookup remote stream endpoint
856     avdtp_sep_t * remote_sep = NULL;
857     uint8_t i;
858     for (i=0; i < sep_discovery_count; i++){
859         if (sep_discovery_seps[i].seid == remote_seid){
860             remote_sep = &sep_discovery_seps[i];
861         }
862     }
863     if (remote_sep == NULL){
864         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
865     }
866 
867     // set media configuration
868     stream_endpoint->remote_configuration_bitmap = store_bit16(stream_endpoint->remote_configuration_bitmap, AVDTP_MEDIA_CODEC, 1);
869     stream_endpoint->remote_configuration.media_codec.media_type = AVDTP_AUDIO;
870     stream_endpoint->remote_configuration.media_codec.media_codec_type = codec_type;
871     // remote seid to use
872     stream_endpoint->set_config_remote_seid = remote_seid;
873     // enable delay reporting if supported
874     if (remote_sep->registered_service_categories & (1<<AVDTP_DELAY_REPORTING)){
875         stream_endpoint->remote_configuration_bitmap = store_bit16(stream_endpoint->remote_configuration_bitmap, AVDTP_DELAY_REPORTING, 1);
876     }
877 
878     // suitable Sink stream endpoint found, configure it
879     connection->a2dp_source_local_stream_endpoint = stream_endpoint;
880     connection->a2dp_source_have_config = true;
881 
882 #ifdef ENABLE_A2DP_SOURCE_EXPLICIT_CONFIG
883     // continue outgoing configuration
884     if (connection->a2dp_source_state == A2DP_DISCOVERY_DONE){
885         connection->a2dp_source_state = A2DP_SET_CONFIGURATION;
886     }
887 #endif
888 
889     return ERROR_CODE_SUCCESS;
890 }
891 
892 uint8_t a2dp_source_set_config_sbc(uint16_t a2dp_cid, uint8_t local_seid, uint8_t remote_seid, const avdtp_configuration_sbc_t * configuration){
893     avdtp_connection_t * connection = avdtp_get_connection_for_avdtp_cid(a2dp_cid);
894     if (connection == NULL){
895         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
896     }
897 
898     uint8_t status = a2dp_source_config_init(connection, local_seid, remote_seid, AVDTP_CODEC_SBC);
899     if (status != 0) {
900         return status;
901     }
902     // set config in reserved buffer
903     connection->a2dp_source_local_stream_endpoint->remote_configuration.media_codec.media_codec_information = (uint8_t *) connection->a2dp_source_local_stream_endpoint->media_codec_info;
904     connection->a2dp_source_local_stream_endpoint->remote_configuration.media_codec.media_codec_information_len = 4;
905     avdtp_config_sbc_store(connection->a2dp_source_local_stream_endpoint->remote_configuration.media_codec.media_codec_information, configuration);
906 
907 #ifdef ENABLE_A2DP_SOURCE_EXPLICIT_CONFIG
908     a2dp_source_set_config(connection);
909 #endif
910 
911     return ERROR_CODE_SUCCESS;
912 }
913 
914 uint8_t a2dp_source_set_config_mpeg_audio(uint16_t a2dp_cid, uint8_t local_seid, uint8_t remote_seid, const avdtp_configuration_mpeg_audio_t * configuration){
915     avdtp_connection_t * connection = avdtp_get_connection_for_avdtp_cid(a2dp_cid);
916     if (connection == NULL){
917         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
918     }
919 
920     uint8_t status = a2dp_source_config_init(connection, local_seid, remote_seid, AVDTP_CODEC_MPEG_1_2_AUDIO);
921     if (status != 0) {
922         return status;
923     }
924 
925     // set config in reserved buffer
926     connection->a2dp_source_local_stream_endpoint->remote_configuration.media_codec.media_codec_information = (uint8_t *)connection->a2dp_source_local_stream_endpoint->media_codec_info;
927     connection->a2dp_source_local_stream_endpoint->remote_configuration.media_codec.media_codec_information_len = 4;
928     avdtp_config_mpeg_audio_store( connection->a2dp_source_local_stream_endpoint->remote_configuration.media_codec.media_codec_information, configuration);
929 
930 #ifdef ENABLE_A2DP_SOURCE_EXPLICIT_CONFIG
931     a2dp_source_set_config(connection);
932 #endif
933 
934     return ERROR_CODE_SUCCESS;
935 }
936 
937 uint8_t a2dp_source_set_config_mpeg_aac(uint16_t a2dp_cid,  uint8_t local_seid,  uint8_t remote_seid, const avdtp_configuration_mpeg_aac_t * configuration){
938     avdtp_connection_t * connection = avdtp_get_connection_for_avdtp_cid(a2dp_cid);
939     if (connection == NULL){
940         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
941     }
942 
943     uint8_t status = a2dp_source_config_init(connection, local_seid, remote_seid, AVDTP_CODEC_MPEG_2_4_AAC);
944     if (status != 0) {
945         return status;
946     }
947     connection->a2dp_source_local_stream_endpoint->remote_configuration.media_codec.media_codec_information = (uint8_t *) connection->a2dp_source_local_stream_endpoint->media_codec_info;
948     connection->a2dp_source_local_stream_endpoint->remote_configuration.media_codec.media_codec_information_len = 6;
949     avdtp_config_mpeg_aac_store( connection->a2dp_source_local_stream_endpoint->remote_configuration.media_codec.media_codec_information, configuration);
950 
951 #ifdef ENABLE_A2DP_SOURCE_EXPLICIT_CONFIG
952     a2dp_source_set_config(connection);
953 #endif
954 
955     return ERROR_CODE_SUCCESS;
956 }
957 
958 uint8_t a2dp_source_set_config_atrac(uint16_t a2dp_cid, uint8_t local_seid, uint8_t remote_seid, const avdtp_configuration_atrac_t * configuration){
959     avdtp_connection_t * connection = avdtp_get_connection_for_avdtp_cid(a2dp_cid);
960     if (connection == NULL){
961         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
962     }
963 
964     uint8_t status = a2dp_source_config_init(connection, local_seid, remote_seid, AVDTP_CODEC_ATRAC_FAMILY);
965     if (status != 0) {
966         return status;
967     }
968 
969     connection->a2dp_source_local_stream_endpoint->remote_configuration.media_codec.media_codec_information = (uint8_t *) connection->a2dp_source_local_stream_endpoint->media_codec_info;
970     connection->a2dp_source_local_stream_endpoint->remote_configuration.media_codec.media_codec_information_len = 7;
971     avdtp_config_atrac_store( connection->a2dp_source_local_stream_endpoint->remote_configuration.media_codec.media_codec_information, configuration);
972 
973 #ifdef ENABLE_A2DP_SOURCE_EXPLICIT_CONFIG
974     a2dp_source_set_config(connection);
975 #endif
976 
977     return ERROR_CODE_SUCCESS;
978 }
979 
980 uint8_t a2dp_source_set_config_other(uint16_t a2dp_cid,  uint8_t local_seid, uint8_t remote_seid,
981                                      const uint8_t * media_codec_information, uint8_t media_codec_information_len){
982     avdtp_connection_t * connection = avdtp_get_connection_for_avdtp_cid(a2dp_cid);
983     if (connection == NULL){
984         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
985     }
986 
987     uint8_t status = a2dp_source_config_init(connection, local_seid, remote_seid, AVDTP_CODEC_NON_A2DP);
988     if (status != 0) {
989         return status;
990     }
991 
992     connection->a2dp_source_local_stream_endpoint->remote_configuration.media_codec.media_codec_information = (uint8_t *) media_codec_information;
993     connection->a2dp_source_local_stream_endpoint->remote_configuration.media_codec.media_codec_information_len = media_codec_information_len;
994 
995 #ifdef ENABLE_A2DP_SOURCE_EXPLICIT_CONFIG
996     a2dp_source_set_config(connection);
997 #endif
998 
999     return status;
1000 }
1001 
1002 uint8_t a2dp_source_reconfigure_stream_sampling_frequency(uint16_t avdtp_cid, uint32_t sampling_frequency){
1003     avdtp_connection_t * connection = avdtp_get_connection_for_avdtp_cid(avdtp_cid);
1004     if (connection == NULL){
1005         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
1006     }
1007 
1008     if (connection->a2dp_source_state != A2DP_STREAMING_OPENED) {
1009         return ERROR_CODE_COMMAND_DISALLOWED;
1010     }
1011 
1012     btstack_assert(connection->a2dp_source_local_stream_endpoint != NULL);
1013 
1014     log_info("Reconfigure avdtp_cid 0x%02x", avdtp_cid);
1015 
1016     avdtp_media_codec_type_t codec_type = connection->a2dp_source_local_stream_endpoint->sep.capabilities.media_codec.media_codec_type;
1017     uint8_t codec_info_len;
1018     switch (codec_type){
1019         case AVDTP_CODEC_SBC:
1020             codec_info_len = 4;
1021             (void)memcpy(connection->a2dp_source_local_stream_endpoint->media_codec_info, connection->a2dp_source_local_stream_endpoint->remote_sep.configuration.media_codec.media_codec_information, codec_info_len);
1022             avdtp_config_sbc_set_sampling_frequency(connection->a2dp_source_local_stream_endpoint->media_codec_info, sampling_frequency);
1023             break;
1024         case AVDTP_CODEC_MPEG_1_2_AUDIO:
1025             codec_info_len = 4;
1026             (void)memcpy(connection->a2dp_source_local_stream_endpoint->media_codec_info, connection->a2dp_source_local_stream_endpoint->remote_sep.configuration.media_codec.media_codec_information, codec_info_len);
1027             avdtp_config_mpeg_audio_set_sampling_frequency(connection->a2dp_source_local_stream_endpoint->media_codec_info, sampling_frequency);
1028             break;
1029         case AVDTP_CODEC_MPEG_2_4_AAC:
1030             codec_info_len = 6;
1031             (void)memcpy(connection->a2dp_source_local_stream_endpoint->media_codec_info, connection->a2dp_source_local_stream_endpoint->remote_sep.configuration.media_codec.media_codec_information, codec_info_len);
1032             avdtp_config_mpeg_aac_set_sampling_frequency(connection->a2dp_source_local_stream_endpoint->media_codec_info, sampling_frequency);
1033             break;
1034         case AVDTP_CODEC_ATRAC_FAMILY:
1035             codec_info_len = 7;
1036             (void)memcpy(connection->a2dp_source_local_stream_endpoint->media_codec_info, connection->a2dp_source_local_stream_endpoint->remote_sep.configuration.media_codec.media_codec_information, codec_info_len);
1037             avdtp_config_atrac_set_sampling_frequency(connection->a2dp_source_local_stream_endpoint->media_codec_info, sampling_frequency);
1038             break;
1039         default:
1040             return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
1041     }
1042 
1043     avdtp_capabilities_t new_configuration;
1044     new_configuration.media_codec.media_type = AVDTP_AUDIO;
1045     new_configuration.media_codec.media_codec_type = codec_type;
1046     new_configuration.media_codec.media_codec_information_len = codec_info_len;
1047     new_configuration.media_codec.media_codec_information = connection->a2dp_source_local_stream_endpoint->media_codec_info;
1048 
1049     // start reconfigure
1050     connection->a2dp_source_state = A2DP_W2_RECONFIGURE_WITH_SEID;
1051 
1052     return avdtp_source_reconfigure(
1053             avdtp_cid,
1054             avdtp_stream_endpoint_seid(connection->a2dp_source_local_stream_endpoint),
1055             connection->a2dp_source_local_stream_endpoint->remote_sep.seid,
1056             1 << AVDTP_MEDIA_CODEC,
1057             new_configuration
1058     );
1059 }
1060