xref: /btstack/src/classic/a2dp_source.c (revision 9900b7faadb8bdbe644bd320a92c25fd9bd22e02)
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 #define __BTSTACK_FILE__ "a2dp_source.c"
40 
41 #include <stdint.h>
42 #include <stdio.h>
43 #include <stdlib.h>
44 #include <string.h>
45 
46 #include "btstack.h"
47 #include "classic/avdtp.h"
48 #include "classic/avdtp_util.h"
49 #include "classic/avdtp_source.h"
50 #include "classic/a2dp_source.h"
51 
52 #define AVDTP_MEDIA_PAYLOAD_HEADER_SIZE 12
53 
54 static const char * default_a2dp_source_service_name = "BTstack A2DP Source Service";
55 static const char * default_a2dp_source_service_provider_name = "BTstack A2DP Source Service Provider";
56 static avdtp_context_t a2dp_source_context;
57 
58 static a2dp_state_t app_state = A2DP_IDLE;
59 static avdtp_stream_endpoint_context_t sc;
60 
61 static void packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
62 
63 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){
64     uint8_t* attribute;
65     de_create_sequence(service);
66 
67     // 0x0000 "Service Record Handle"
68     de_add_number(service, DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_SERVICE_RECORD_HANDLE);
69     de_add_number(service, DE_UINT, DE_SIZE_32, service_record_handle);
70 
71     // 0x0001 "Service Class ID List"
72     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_SERVICE_CLASS_ID_LIST);
73     attribute = de_push_sequence(service);
74     {
75         de_add_number(attribute, DE_UUID, DE_SIZE_16, BLUETOOTH_SERVICE_CLASS_AUDIO_SOURCE);
76     }
77     de_pop_sequence(service, attribute);
78 
79     // 0x0004 "Protocol Descriptor List"
80     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_PROTOCOL_DESCRIPTOR_LIST);
81     attribute = de_push_sequence(service);
82     {
83         uint8_t* l2cpProtocol = de_push_sequence(attribute);
84         {
85             de_add_number(l2cpProtocol,  DE_UUID, DE_SIZE_16, BLUETOOTH_PROTOCOL_L2CAP);
86             de_add_number(l2cpProtocol,  DE_UINT, DE_SIZE_16, BLUETOOTH_PROTOCOL_AVDTP);
87         }
88         de_pop_sequence(attribute, l2cpProtocol);
89 
90         uint8_t* avProtocol = de_push_sequence(attribute);
91         {
92             de_add_number(avProtocol,  DE_UUID, DE_SIZE_16, BLUETOOTH_PROTOCOL_AVDTP);  // avProtocol_service
93             de_add_number(avProtocol,  DE_UINT, DE_SIZE_16,  0x0103);  // version
94         }
95         de_pop_sequence(attribute, avProtocol);
96     }
97     de_pop_sequence(service, attribute);
98 
99     // 0x0005 "Public Browse Group"
100     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_BROWSE_GROUP_LIST); // public browse group
101     attribute = de_push_sequence(service);
102     {
103         de_add_number(attribute,  DE_UUID, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_PUBLIC_BROWSE_ROOT);
104     }
105     de_pop_sequence(service, attribute);
106 
107     // 0x0009 "Bluetooth Profile Descriptor List"
108     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_BLUETOOTH_PROFILE_DESCRIPTOR_LIST);
109     attribute = de_push_sequence(service);
110     {
111         uint8_t *a2dProfile = de_push_sequence(attribute);
112         {
113             de_add_number(a2dProfile,  DE_UUID, DE_SIZE_16, BLUETOOTH_SERVICE_CLASS_ADVANCED_AUDIO_DISTRIBUTION);
114             de_add_number(a2dProfile,  DE_UINT, DE_SIZE_16, 0x0103);
115         }
116         de_pop_sequence(attribute, a2dProfile);
117     }
118     de_pop_sequence(service, attribute);
119 
120 
121     // 0x0100 "Service Name"
122     de_add_number(service,  DE_UINT, DE_SIZE_16, 0x0100);
123     if (service_name){
124         de_add_data(service,  DE_STRING, strlen(service_name), (uint8_t *) service_name);
125     } else {
126         de_add_data(service,  DE_STRING, strlen(default_a2dp_source_service_name), (uint8_t *) default_a2dp_source_service_name);
127     }
128 
129     // 0x0100 "Provider Name"
130     de_add_number(service,  DE_UINT, DE_SIZE_16, 0x0102);
131     if (service_provider_name){
132         de_add_data(service,  DE_STRING, strlen(service_provider_name), (uint8_t *) service_provider_name);
133     } else {
134         de_add_data(service,  DE_STRING, strlen(default_a2dp_source_service_provider_name), (uint8_t *) default_a2dp_source_service_provider_name);
135     }
136 
137     // 0x0311 "Supported Features"
138     de_add_number(service, DE_UINT, DE_SIZE_16, 0x0311);
139     de_add_number(service, DE_UINT, DE_SIZE_16, supported_features);
140 }
141 
142 
143 static void a2dp_streaming_emit_can_send_media_packet_now(btstack_packet_handler_t callback, uint16_t cid, uint8_t seid){
144     if (!callback) return;
145     uint8_t event[8];
146     int pos = 0;
147     event[pos++] = HCI_EVENT_A2DP_META;
148     event[pos++] = sizeof(event) - 2;
149     event[pos++] = A2DP_SUBEVENT_STREAMING_CAN_SEND_MEDIA_PACKET_NOW;
150     little_endian_store_16(event, pos, cid);
151     pos += 2;
152     event[pos++] = seid;
153     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
154 }
155 
156 static inline void a2dp_signaling_emit_media_codec_sbc(btstack_packet_handler_t callback, uint8_t * event, uint16_t event_size){
157     if (!callback) return;
158     if (event_size < 18) return;
159     event[0] = HCI_EVENT_A2DP_META;
160     event[2] = A2DP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CONFIGURATION;
161     (*callback)(HCI_EVENT_PACKET, 0, event, event_size);
162 }
163 
164 static inline void a2dp_signaling_emit_reject_cmd(btstack_packet_handler_t callback, uint8_t * event, uint16_t event_size){
165     if (!callback) return;
166     if (event_size < 18) return;
167     event[0] = HCI_EVENT_A2DP_META;
168     event[2] = A2DP_SUBEVENT_COMMAND_REJECTED;
169     (*callback)(HCI_EVENT_PACKET, 0, event, event_size);
170 }
171 
172 static void packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
173     UNUSED(channel);
174     UNUSED(size);
175 
176     uint8_t signal_identifier;
177     uint8_t status;
178     uint8_t local_seid;
179     uint8_t remote_seid;
180     uint16_t cid;
181     bd_addr_t address;
182 
183     if (packet_type != HCI_EVENT_PACKET) return;
184     if (hci_event_packet_get_type(packet) != HCI_EVENT_AVDTP_META) return;
185 
186     switch (packet[2]){
187         case AVDTP_SUBEVENT_SIGNALING_CONNECTION_ESTABLISHED:{
188             avdtp_subevent_signaling_connection_established_get_bd_addr(packet, sc.remote_addr);
189             cid = avdtp_subevent_signaling_connection_established_get_avdtp_cid(packet);
190             status = avdtp_subevent_signaling_connection_established_get_status(packet);
191 
192             if (status != 0){
193                 log_info("AVDTP_SUBEVENT_SIGNALING_CONNECTION failed status %d ---", status);
194                 a2dp_streaming_emit_connection_established(a2dp_source_context.a2dp_callback, cid, sc.remote_addr, 0, 0, status);
195                 break;
196             }
197             log_info("A2DP_SUBEVENT_SIGNALING_CONNECTION established avdtp_cid 0x%02x ---", a2dp_source_context.avdtp_cid);
198 
199             sc.active_remote_sep = NULL;
200             sc.active_remote_sep_index = 0;
201             uint8_t event[11];
202             int pos = 0;
203             event[pos++] = HCI_EVENT_A2DP_META;
204             event[pos++] = sizeof(event) - 2;
205             event[pos++] = A2DP_SUBEVENT_SIGNALING_CONNECTION_ESTABLISHED;
206             little_endian_store_16(event, pos, cid);
207             pos += 2;
208             reverse_bd_addr(event+pos, sc.remote_addr);
209             pos += 6;
210             (*a2dp_source_context.a2dp_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
211             app_state = A2DP_W2_DISCOVER_SEPS;
212             avdtp_source_discover_stream_endpoints(cid);
213             break;
214         }
215         case AVDTP_SUBEVENT_SIGNALING_SEP_FOUND:
216             break;
217 
218         case AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CAPABILITY:{
219             log_info("A2DP received SBC capability.");
220             if (!sc.local_stream_endpoint) {
221                 log_error("invalid local seid %d", avdtp_subevent_signaling_media_codec_sbc_capability_get_local_seid(packet));
222                 return;
223             }
224             log_info("A2DP received SBC capability.");
225 
226             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));
227             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));
228             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));
229             uint8_t subbands = avdtp_choose_sbc_subbands(sc.local_stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_subbands_bitmap(packet));
230 
231             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));
232             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));
233             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));
234 
235             sc.local_stream_endpoint->remote_configuration.media_codec.media_codec_information[0] = (sampling_frequency << 4) | channel_mode;
236             sc.local_stream_endpoint->remote_configuration.media_codec.media_codec_information[1] = (block_length << 4) | (subbands << 2) | allocation_method;
237             sc.local_stream_endpoint->remote_configuration.media_codec.media_codec_information[2] = min_bitpool_value;
238             sc.local_stream_endpoint->remote_configuration.media_codec.media_codec_information[3] = max_bitpool_value;
239 
240             sc.local_stream_endpoint->remote_configuration_bitmap = store_bit16(sc.local_stream_endpoint->remote_configuration_bitmap, AVDTP_MEDIA_CODEC, 1);
241             sc.local_stream_endpoint->remote_configuration.media_codec.media_type = AVDTP_AUDIO;
242             sc.local_stream_endpoint->remote_configuration.media_codec.media_codec_type = AVDTP_CODEC_SBC;
243 
244             app_state = A2DP_W2_SET_CONFIGURATION;
245             break;
246         }
247         case AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_OTHER_CAPABILITY:
248             log_info("received non SBC codec. not implemented");
249             break;
250 
251         case AVDTP_SUBEVENT_SIGNALING_MEDIA_TRANSPORT_CAPABILITY:
252             log_info("received, but not forwarded: AVDTP_SUBEVENT_SIGNALING_MEDIA_TRANSPORT_CAPABILITY, remote seid %d\n", avdtp_subevent_signaling_media_transport_capability_get_remote_seid(packet));
253             break;
254         case AVDTP_SUBEVENT_SIGNALING_REPORTING_CAPABILITY:
255             log_info("received, but not forwarded: AVDTP_SUBEVENT_SIGNALING_REPORTING_CAPABILITY, remote seid %d\n", avdtp_subevent_signaling_reporting_capability_get_remote_seid(packet));
256             break;
257         case AVDTP_SUBEVENT_SIGNALING_DELAY_REPORTING_CAPABILITY:
258             log_info("received, but not forwarded: AVDTP_SUBEVENT_SIGNALING_DELAY_REPORTING_CAPABILITY, remote seid %d\n", avdtp_subevent_signaling_delay_reporting_capability_get_remote_seid(packet));
259             break;
260         case AVDTP_SUBEVENT_SIGNALING_RECOVERY_CAPABILITY:
261             log_info("received, but not forwarded: AVDTP_SUBEVENT_SIGNALING_RECOVERY_CAPABILITY, remote seid %d\n", avdtp_subevent_signaling_recovery_capability_get_remote_seid(packet));
262             break;
263         case AVDTP_SUBEVENT_SIGNALING_CONTENT_PROTECTION_CAPABILITY:
264             log_info("received, but not forwarded: AVDTP_SUBEVENT_SIGNALING_CONTENT_PROTECTION_CAPABILITY, remote seid %d\n", avdtp_subevent_signaling_content_protection_capability_get_remote_seid(packet));
265             break;
266         case AVDTP_SUBEVENT_SIGNALING_HEADER_COMPRESSION_CAPABILITY:
267             log_info("received, but not forwarded: AVDTP_SUBEVENT_SIGNALING_HEADER_COMPRESSION_CAPABILITY, remote seid %d\n", avdtp_subevent_signaling_header_compression_capability_get_remote_seid(packet));
268             break;
269         case AVDTP_SUBEVENT_SIGNALING_MULTIPLEXING_CAPABILITY:
270             log_info("received, but not forwarded: AVDTP_SUBEVENT_SIGNALING_MULTIPLEXING_CAPABILITY, remote seid %d\n", avdtp_subevent_signaling_multiplexing_capability_get_remote_seid(packet));
271             break;
272         case AVDTP_SUBEVENT_SIGNALING_CAPABILITY_DONE:
273             break;
274 
275         case AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CONFIGURATION:{
276             // TODO check cid
277             sc.sampling_frequency = avdtp_subevent_signaling_media_codec_sbc_configuration_get_sampling_frequency(packet);
278             sc.block_length = avdtp_subevent_signaling_media_codec_sbc_configuration_get_block_length(packet);
279             sc.subbands = avdtp_subevent_signaling_media_codec_sbc_configuration_get_subbands(packet);
280             sc.allocation_method = avdtp_subevent_signaling_media_codec_sbc_configuration_get_allocation_method(packet) - 1;
281             sc.max_bitpool_value = avdtp_subevent_signaling_media_codec_sbc_configuration_get_max_bitpool_value(packet);
282             sc.channel_mode = avdtp_subevent_signaling_media_codec_sbc_configuration_get_channel_mode(packet);
283             // TODO: deal with reconfigure: avdtp_subevent_signaling_media_codec_sbc_configuration_get_reconfigure(packet);
284             log_info("A2DP received SBC Config: sample rate %u, max bitpool %u.", sc.sampling_frequency, sc.max_bitpool_value);
285             app_state = A2DP_W2_OPEN_STREAM_WITH_SEID;
286             a2dp_signaling_emit_media_codec_sbc(a2dp_source_context.a2dp_callback, packet, size);
287             break;
288         }
289 
290         case AVDTP_SUBEVENT_STREAMING_CAN_SEND_MEDIA_PACKET_NOW:
291             cid = avdtp_subevent_streaming_can_send_media_packet_now_get_avdtp_cid(packet);
292             a2dp_streaming_emit_can_send_media_packet_now(a2dp_source_context.a2dp_callback, cid, 0);
293             break;
294 
295         case AVDTP_SUBEVENT_STREAMING_CONNECTION_ESTABLISHED:
296             avdtp_subevent_streaming_connection_established_get_bd_addr(packet, address);
297             status = avdtp_subevent_streaming_connection_established_get_status(packet);
298             cid = avdtp_subevent_streaming_connection_established_get_avdtp_cid(packet);
299             remote_seid = avdtp_subevent_streaming_connection_established_get_remote_seid(packet);
300             local_seid  = avdtp_subevent_streaming_connection_established_get_local_seid(packet);
301             if (status != 0){
302                 log_info("AVDTP_SUBEVENT_STREAMING_CONNECTION could not be established, status %d ---", status);
303                 a2dp_streaming_emit_connection_established(a2dp_source_context.a2dp_callback, cid, address, local_seid, remote_seid, status);
304                 break;
305             }
306             log_info("AVDTP_SUBEVENT_STREAMING_CONNECTION_ESTABLISHED --- avdtp_cid 0x%02x, local seid %d, remote seid %d", cid, local_seid, remote_seid);
307             app_state = A2DP_STREAMING_OPENED;
308             a2dp_streaming_emit_connection_established(a2dp_source_context.a2dp_callback, cid, address, local_seid, remote_seid, 0);
309             break;
310 
311         case AVDTP_SUBEVENT_SIGNALING_ACCEPT:
312             // TODO check cid
313             signal_identifier = avdtp_subevent_signaling_accept_get_signal_identifier(packet);
314             cid = avdtp_subevent_signaling_accept_get_avdtp_cid(packet);
315             log_info("A2DP Accepted %d, state %d", signal_identifier, app_state);
316 
317             switch (app_state){
318                 case A2DP_W2_DISCOVER_SEPS:
319                 case A2DP_W2_GET_CAPABILITIES:
320                 case A2DP_W2_GET_ALL_CAPABILITIES:
321                     app_state = A2DP_W2_GET_ALL_CAPABILITIES;
322                     sc.active_remote_sep = avdtp_source_remote_sep(cid, sc.active_remote_sep_index++);
323                     if (!sc.active_remote_sep) {
324                         app_state = A2DP_IDLE;
325                         a2dp_streaming_emit_connection_established(a2dp_source_context.a2dp_callback, cid, sc.remote_addr, 0, 0, AVDTP_SEID_DOES_NOT_EXIST);
326                         break;
327                     }
328                     avdtp_source_get_capabilities(cid, sc.active_remote_sep->seid);
329                     break;
330                 case A2DP_W2_SET_CONFIGURATION:{
331                     if (!sc.local_stream_endpoint) return;
332                     log_info("A2DP initiate set configuration locally and wait for response ... ");
333                     app_state = A2DP_IDLE;
334                     avdtp_source_set_configuration(cid, avdtp_stream_endpoint_seid(sc.local_stream_endpoint), sc.active_remote_sep->seid, sc.local_stream_endpoint->remote_configuration_bitmap, sc.local_stream_endpoint->remote_configuration);
335                     break;
336                 }
337                 case A2DP_W2_OPEN_STREAM_WITH_SEID:{
338                     log_info("A2DP open stream ");
339                     app_state = A2DP_W4_OPEN_STREAM_WITH_SEID;
340                     avdtp_source_open_stream(cid, avdtp_stream_endpoint_seid(sc.local_stream_endpoint), sc.active_remote_sep->seid);
341                     break;
342                 }
343                 case A2DP_STREAMING_OPENED:
344                     if (!a2dp_source_context.a2dp_callback) return;
345                     switch (signal_identifier){
346                         case  AVDTP_SI_START:{
347                             uint8_t event[6];
348                             int pos = 0;
349                             event[pos++] = HCI_EVENT_A2DP_META;
350                             event[pos++] = sizeof(event) - 2;
351                             event[pos++] = A2DP_SUBEVENT_STREAM_STARTED;
352                             little_endian_store_16(event, pos, cid);
353                             pos += 2;
354                             event[pos++] = avdtp_stream_endpoint_seid(sc.local_stream_endpoint);
355                             (*a2dp_source_context.a2dp_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
356                             break;
357                         }
358                         case AVDTP_SI_SUSPEND:{
359                             uint8_t event[6];
360                             int pos = 0;
361                             event[pos++] = HCI_EVENT_A2DP_META;
362                             event[pos++] = sizeof(event) - 2;
363                             event[pos++] = A2DP_SUBEVENT_STREAM_SUSPENDED;
364                             little_endian_store_16(event, pos, cid);
365                             pos += 2;
366                             event[pos++] = avdtp_stream_endpoint_seid(sc.local_stream_endpoint);
367                             (*a2dp_source_context.a2dp_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
368                             break;
369                         }
370                         case AVDTP_SI_ABORT:
371                         case AVDTP_SI_CLOSE:{
372                             uint8_t event[6];
373                             int pos = 0;
374                             event[pos++] = HCI_EVENT_A2DP_META;
375                             event[pos++] = sizeof(event) - 2;
376                             event[pos++] = A2DP_SUBEVENT_STREAM_STOPPED;
377                             little_endian_store_16(event, pos, cid);
378                             pos += 2;
379                             event[pos++] = avdtp_stream_endpoint_seid(sc.local_stream_endpoint);
380                             (*a2dp_source_context.a2dp_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
381                             break;
382                         }
383                         default:
384                             break;
385                     }
386                     break;
387                 default:
388                     app_state = A2DP_IDLE;
389                     break;
390             }
391 
392             break;
393         case AVDTP_SUBEVENT_SIGNALING_REJECT:
394         case AVDTP_SUBEVENT_SIGNALING_GENERAL_REJECT:
395             app_state = A2DP_IDLE;
396             a2dp_signaling_emit_reject_cmd(a2dp_source_context.a2dp_callback, packet, size);
397             break;
398         case AVDTP_SUBEVENT_SIGNALING_CONNECTION_RELEASED:{
399             app_state = A2DP_IDLE;
400             uint8_t event[6];
401             int pos = 0;
402             event[pos++] = HCI_EVENT_A2DP_META;
403             event[pos++] = sizeof(event) - 2;
404             event[pos++] = A2DP_SUBEVENT_SIGNALING_CONNECTION_RELEASED;
405             little_endian_store_16(event, pos, avdtp_subevent_streaming_connection_released_get_avdtp_cid(packet));
406             pos += 2;
407             event[pos++] = avdtp_subevent_streaming_connection_released_get_local_seid(packet);
408             (*a2dp_source_context.a2dp_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
409             break;
410         }
411         case AVDTP_SUBEVENT_STREAMING_CONNECTION_RELEASED:{
412             app_state = A2DP_IDLE;
413             uint8_t event[6];
414             int pos = 0;
415             event[pos++] = HCI_EVENT_A2DP_META;
416             event[pos++] = sizeof(event) - 2;
417             event[pos++] = A2DP_SUBEVENT_STREAM_RELEASED;
418             little_endian_store_16(event, pos, avdtp_subevent_streaming_connection_released_get_avdtp_cid(packet));
419             pos += 2;
420             event[pos++] = avdtp_subevent_streaming_connection_released_get_local_seid(packet);
421             (*a2dp_source_context.a2dp_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
422             break;
423         }
424         default:
425             app_state = A2DP_IDLE;
426             log_info("not implemented");
427             break;
428     }
429 }
430 void a2dp_source_register_packet_handler(btstack_packet_handler_t callback){
431     if (callback == NULL){
432         log_error("a2dp_source_register_packet_handler called with NULL callback");
433         return;
434     }
435     avdtp_source_register_packet_handler(&packet_handler);
436     a2dp_source_context.a2dp_callback = callback;
437 }
438 
439 void a2dp_source_init(void){
440     avdtp_source_init(&a2dp_source_context);
441     l2cap_register_service(&packet_handler, BLUETOOTH_PROTOCOL_AVDTP, 0xffff, LEVEL_0);
442 }
443 
444 avdtp_stream_endpoint_t * a2dp_source_create_stream_endpoint(avdtp_media_type_t media_type, avdtp_media_codec_type_t media_codec_type,
445     uint8_t * codec_capabilities, uint16_t codec_capabilities_len,
446     uint8_t * media_codec_info, uint16_t media_codec_info_len){
447     avdtp_stream_endpoint_t * local_stream_endpoint = avdtp_source_create_stream_endpoint(AVDTP_SOURCE, media_type);
448     if (!local_stream_endpoint){
449         return NULL;
450     }
451     avdtp_source_register_media_transport_category(avdtp_stream_endpoint_seid(local_stream_endpoint));
452     avdtp_source_register_media_codec_category(avdtp_stream_endpoint_seid(local_stream_endpoint), media_type, media_codec_type,
453         codec_capabilities, codec_capabilities_len);
454     local_stream_endpoint->remote_configuration.media_codec.media_codec_information     = media_codec_info;
455     local_stream_endpoint->remote_configuration.media_codec.media_codec_information_len = media_codec_info_len;
456     sc.local_stream_endpoint = local_stream_endpoint;
457     return local_stream_endpoint;
458 }
459 
460 uint8_t a2dp_source_establish_stream(bd_addr_t remote_addr, uint8_t loc_seid, uint16_t * a2dp_cid){
461     sc.local_stream_endpoint = avdtp_stream_endpoint_for_seid(loc_seid, &a2dp_source_context);
462     if (!sc.local_stream_endpoint){
463         log_error(" no local_stream_endpoint for seid %d", loc_seid);
464         return AVDTP_SEID_DOES_NOT_EXIST;
465     }
466     memcpy(sc.remote_addr, remote_addr, 6);
467     return avdtp_source_connect(remote_addr, a2dp_cid);
468 }
469 
470 uint8_t a2dp_source_disconnect(uint16_t a2dp_cid){
471     return avdtp_disconnect(a2dp_cid, &a2dp_source_context);
472 }
473 
474 uint8_t a2dp_source_start_stream(uint16_t a2dp_cid, uint8_t local_seid){
475     return avdtp_start_stream(a2dp_cid, local_seid, &a2dp_source_context);
476 }
477 
478 uint8_t a2dp_source_pause_stream(uint16_t a2dp_cid, uint8_t local_seid){
479     return avdtp_suspend_stream(a2dp_cid, local_seid, &a2dp_source_context);
480 }
481 
482 static void a2dp_source_setup_media_header(uint8_t * media_packet, int size, int *offset, uint8_t marker, uint16_t sequence_number){
483     if (size < AVDTP_MEDIA_PAYLOAD_HEADER_SIZE){
484         log_error("small outgoing buffer");
485         return;
486     }
487 
488     uint8_t  rtp_version = 2;
489     uint8_t  padding = 0;
490     uint8_t  extension = 0;
491     uint8_t  csrc_count = 0;
492     uint8_t  payload_type = 0x60;
493     // uint16_t sequence_number = stream_endpoint->sequence_number;
494     uint32_t timestamp = btstack_run_loop_get_time_ms();
495     uint32_t ssrc = 0x11223344;
496 
497     // rtp header (min size 12B)
498     int pos = 0;
499     // int mtu = l2cap_get_remote_mtu_for_local_cid(stream_endpoint->l2cap_media_cid);
500 
501     media_packet[pos++] = (rtp_version << 6) | (padding << 5) | (extension << 4) | csrc_count;
502     media_packet[pos++] = (marker << 1) | payload_type;
503     big_endian_store_16(media_packet, pos, sequence_number);
504     pos += 2;
505     big_endian_store_32(media_packet, pos, timestamp);
506     pos += 4;
507     big_endian_store_32(media_packet, pos, ssrc); // only used for multicast
508     pos += 4;
509     *offset = pos;
510 }
511 
512 void a2dp_source_stream_endpoint_request_can_send_now(uint16_t a2dp_cid, uint8_t local_seid){
513     avdtp_stream_endpoint_t * stream_endpoint = avdtp_stream_endpoint_for_seid(local_seid, &a2dp_source_context);
514     if (!stream_endpoint) {
515         log_error("A2DP source: no stream_endpoint with seid %d", local_seid);
516         return;
517     }
518     if (a2dp_source_context.avdtp_cid != a2dp_cid){
519         log_error("A2DP source: a2dp cid 0x%02x not known, expected 0x%02x", a2dp_cid, a2dp_source_context.avdtp_cid);
520         return;
521     }
522     stream_endpoint->send_stream = 1;
523     avdtp_request_can_send_now_initiator(stream_endpoint->connection, stream_endpoint->l2cap_media_cid);
524 }
525 
526 int a2dp_max_media_payload_size(uint16_t a2dp_cid, uint8_t local_seid){
527     avdtp_stream_endpoint_t * stream_endpoint = avdtp_stream_endpoint_for_seid(local_seid, &a2dp_source_context);
528     if (!stream_endpoint) {
529         log_error("A2DP source: no stream_endpoint with seid %d", local_seid);
530         return 0;
531     }
532     if (a2dp_source_context.avdtp_cid != a2dp_cid){
533         log_error("A2DP source: a2dp cid 0x%02x not known, expected 0x%02x", a2dp_cid, a2dp_source_context.avdtp_cid);
534         return 0;
535     }
536 
537     if (stream_endpoint->l2cap_media_cid == 0){
538         log_error("A2DP source: no media connection for seid %d", local_seid);
539         return 0;
540     }
541     return l2cap_get_remote_mtu_for_local_cid(stream_endpoint->l2cap_media_cid) - AVDTP_MEDIA_PAYLOAD_HEADER_SIZE;
542 }
543 
544 static void a2dp_source_copy_media_payload(uint8_t * media_packet, int size, int * offset, uint8_t * storage, int num_bytes_to_copy, uint8_t num_frames){
545     if (size < num_bytes_to_copy + 1){
546         log_error("small outgoing buffer: buffer size %u, but need %u", size, num_bytes_to_copy + 1);
547         return;
548     }
549 
550     int pos = *offset;
551     media_packet[pos++] = num_frames; // (fragmentation << 7) | (starting_packet << 6) | (last_packet << 5) | num_frames;
552     memcpy(media_packet + pos, storage, num_bytes_to_copy);
553     pos += num_bytes_to_copy;
554     *offset = pos;
555 }
556 
557 int a2dp_source_stream_send_media_payload(uint16_t a2dp_cid, uint8_t local_seid, uint8_t * storage, int num_bytes_to_copy, uint8_t num_frames, uint8_t marker){
558     avdtp_stream_endpoint_t * stream_endpoint = avdtp_stream_endpoint_for_seid(local_seid, &a2dp_source_context);
559     if (!stream_endpoint) {
560         log_error("A2DP source: no stream_endpoint with seid %d", local_seid);
561         return 0;
562     }
563     if (a2dp_source_context.avdtp_cid != a2dp_cid){
564         log_error("A2DP source: a2dp cid 0x%02x not known, expected 0x%02x", a2dp_cid, a2dp_source_context.avdtp_cid);
565         return 0;
566     }
567 
568     if (stream_endpoint->l2cap_media_cid == 0){
569         log_error("A2DP source: no media connection for seid %d", local_seid);
570         return 0;
571     }
572 
573     int size = l2cap_get_remote_mtu_for_local_cid(stream_endpoint->l2cap_media_cid);
574     int offset = 0;
575 
576     l2cap_reserve_packet_buffer();
577     uint8_t * media_packet = l2cap_get_outgoing_buffer();
578     //int size = l2cap_get_remote_mtu_for_local_cid(stream_endpoint->l2cap_media_cid);
579     a2dp_source_setup_media_header(media_packet, size, &offset, marker, stream_endpoint->sequence_number);
580     a2dp_source_copy_media_payload(media_packet, size, &offset, storage, num_bytes_to_copy, num_frames);
581     stream_endpoint->sequence_number++;
582     l2cap_send_prepared(stream_endpoint->l2cap_media_cid, offset);
583     return size;
584 }
585