xref: /btstack/src/classic/a2dp_source.c (revision 360243be41f47158adff357b9fead2686419a2df)
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 "avdtp.h"
48 #include "avdtp_util.h"
49 #include "avdtp_source.h"
50 #include "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 static int next_remote_sep_index_to_query = 0;
61 
62 static void packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
63 
64 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){
65     uint8_t* attribute;
66     de_create_sequence(service);
67 
68     // 0x0000 "Service Record Handle"
69     de_add_number(service, DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_SERVICE_RECORD_HANDLE);
70     de_add_number(service, DE_UINT, DE_SIZE_32, service_record_handle);
71 
72     // 0x0001 "Service Class ID List"
73     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_SERVICE_CLASS_ID_LIST);
74     attribute = de_push_sequence(service);
75     {
76         de_add_number(attribute, DE_UUID, DE_SIZE_16, BLUETOOTH_SERVICE_CLASS_AUDIO_SOURCE);
77     }
78     de_pop_sequence(service, attribute);
79 
80     // 0x0004 "Protocol Descriptor List"
81     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_PROTOCOL_DESCRIPTOR_LIST);
82     attribute = de_push_sequence(service);
83     {
84         uint8_t* l2cpProtocol = de_push_sequence(attribute);
85         {
86             de_add_number(l2cpProtocol,  DE_UUID, DE_SIZE_16, BLUETOOTH_PROTOCOL_L2CAP);
87             de_add_number(l2cpProtocol,  DE_UINT, DE_SIZE_16, BLUETOOTH_PROTOCOL_AVDTP);
88         }
89         de_pop_sequence(attribute, l2cpProtocol);
90 
91         uint8_t* avProtocol = de_push_sequence(attribute);
92         {
93             de_add_number(avProtocol,  DE_UUID, DE_SIZE_16, BLUETOOTH_PROTOCOL_AVDTP);  // avProtocol_service
94             de_add_number(avProtocol,  DE_UINT, DE_SIZE_16,  0x0103);  // version
95         }
96         de_pop_sequence(attribute, avProtocol);
97     }
98     de_pop_sequence(service, attribute);
99 
100     // 0x0005 "Public Browse Group"
101     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_BROWSE_GROUP_LIST); // public browse group
102     attribute = de_push_sequence(service);
103     {
104         de_add_number(attribute,  DE_UUID, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_PUBLIC_BROWSE_ROOT);
105     }
106     de_pop_sequence(service, attribute);
107 
108     // 0x0009 "Bluetooth Profile Descriptor List"
109     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_BLUETOOTH_PROFILE_DESCRIPTOR_LIST);
110     attribute = de_push_sequence(service);
111     {
112         uint8_t *a2dProfile = de_push_sequence(attribute);
113         {
114             de_add_number(a2dProfile,  DE_UUID, DE_SIZE_16, BLUETOOTH_SERVICE_CLASS_ADVANCED_AUDIO_DISTRIBUTION);
115             de_add_number(a2dProfile,  DE_UINT, DE_SIZE_16, 0x0103);
116         }
117         de_pop_sequence(attribute, a2dProfile);
118     }
119     de_pop_sequence(service, attribute);
120 
121 
122     // 0x0100 "Service Name"
123     de_add_number(service,  DE_UINT, DE_SIZE_16, 0x0100);
124     if (service_name){
125         de_add_data(service,  DE_STRING, strlen(service_name), (uint8_t *) service_name);
126     } else {
127         de_add_data(service,  DE_STRING, strlen(default_a2dp_source_service_name), (uint8_t *) default_a2dp_source_service_name);
128     }
129 
130     // 0x0100 "Provider Name"
131     de_add_number(service,  DE_UINT, DE_SIZE_16, 0x0102);
132     if (service_provider_name){
133         de_add_data(service,  DE_STRING, strlen(service_provider_name), (uint8_t *) service_provider_name);
134     } else {
135         de_add_data(service,  DE_STRING, strlen(default_a2dp_source_service_provider_name), (uint8_t *) default_a2dp_source_service_provider_name);
136     }
137 
138     // 0x0311 "Supported Features"
139     de_add_number(service, DE_UINT, DE_SIZE_16, 0x0311);
140     de_add_number(service, DE_UINT, DE_SIZE_16, supported_features);
141 }
142 
143 
144 static void a2dp_streaming_emit_can_send_media_packet_now(btstack_packet_handler_t callback, uint16_t cid, uint8_t seid){
145     if (!callback) return;
146     uint8_t event[8];
147     int pos = 0;
148     event[pos++] = HCI_EVENT_A2DP_META;
149     event[pos++] = sizeof(event) - 2;
150     event[pos++] = A2DP_SUBEVENT_STREAMING_CAN_SEND_MEDIA_PACKET_NOW;
151     little_endian_store_16(event, pos, cid);
152     pos += 2;
153     event[pos++] = seid;
154     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
155 }
156 
157 static void packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
158     UNUSED(channel);
159     UNUSED(size);
160 
161     uint8_t signal_identifier;
162     uint8_t status;
163     uint8_t local_seid;
164     uint8_t remote_seid;
165     uint16_t cid;
166     bd_addr_t address;
167 
168     if (packet_type != HCI_EVENT_PACKET) return;
169     if (hci_event_packet_get_type(packet) != HCI_EVENT_AVDTP_META) return;
170 
171     switch (packet[2]){
172         case AVDTP_SUBEVENT_SIGNALING_CONNECTION_ESTABLISHED:
173             avdtp_subevent_signaling_connection_established_get_bd_addr(packet, sc.remote_addr);
174             cid = avdtp_subevent_signaling_connection_established_get_avdtp_cid(packet);
175             status = avdtp_subevent_signaling_connection_established_get_status(packet);
176             if (status != 0){
177                 log_info("AVDTP_SUBEVENT_SIGNALING_CONNECTION failed status %d ---", status);
178                 a2dp_streaming_emit_connection_established(a2dp_source_context.a2dp_callback, cid, sc.remote_addr, 0, 0, status);
179                 break;
180             }
181 
182             sc.active_remote_sep = NULL;
183             next_remote_sep_index_to_query = 0;
184             if (!sc.local_stream_endpoint) {
185                 app_state = A2DP_CONNECTED;
186                 uint8_t event[11];
187                 int pos = 0;
188                 event[pos++] = HCI_EVENT_A2DP_META;
189                 event[pos++] = sizeof(event) - 2;
190                 event[pos++] = A2DP_SUBEVENT_INCOMING_CONNECTION_ESTABLISHED;
191                 little_endian_store_16(event, pos, cid);
192                 pos += 2;
193                 reverse_bd_addr(event+pos, sc.remote_addr);
194                 pos += 6;
195                 (*a2dp_source_context.a2dp_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
196                 return;
197             }
198 
199             app_state = A2DP_W2_DISCOVER_SEPS;
200             avdtp_source_discover_stream_endpoints(cid);
201             break;
202 
203         case AVDTP_SUBEVENT_SIGNALING_SEP_FOUND:
204             break;
205 
206         case AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CAPABILITY:{
207             if (!sc.local_stream_endpoint) {
208                 // printf("local seid %d \n", avdtp_subevent_signaling_media_codec_sbc_capability_get_local_seid(packet));
209                 return;
210             }
211             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));
212             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));
213             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));
214             uint8_t subbands = avdtp_choose_sbc_subbands(sc.local_stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_subbands_bitmap(packet));
215 
216             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));
217             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));
218             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));
219 
220             sc.local_stream_endpoint->remote_configuration.media_codec.media_codec_information[0] = (sampling_frequency << 4) | channel_mode;
221             sc.local_stream_endpoint->remote_configuration.media_codec.media_codec_information[1] = (block_length << 4) | (subbands << 2) | allocation_method;
222             sc.local_stream_endpoint->remote_configuration.media_codec.media_codec_information[2] = min_bitpool_value;
223             sc.local_stream_endpoint->remote_configuration.media_codec.media_codec_information[3] = max_bitpool_value;
224 
225             sc.local_stream_endpoint->remote_configuration_bitmap = store_bit16(sc.local_stream_endpoint->remote_configuration_bitmap, AVDTP_MEDIA_CODEC, 1);
226             sc.local_stream_endpoint->remote_configuration.media_codec.media_type = AVDTP_AUDIO;
227             sc.local_stream_endpoint->remote_configuration.media_codec.media_codec_type = AVDTP_CODEC_SBC;
228 
229             app_state = A2DP_W2_SET_CONFIGURATION;
230             break;
231         }
232         case AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_OTHER_CAPABILITY:
233             log_info("received non SBC codec. not implemented");
234             break;
235 
236         case AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CONFIGURATION:{
237             // TODO check cid
238             sc.sampling_frequency = avdtp_subevent_signaling_media_codec_sbc_configuration_get_sampling_frequency(packet);
239             sc.block_length = avdtp_subevent_signaling_media_codec_sbc_configuration_get_block_length(packet);
240             sc.subbands = avdtp_subevent_signaling_media_codec_sbc_configuration_get_subbands(packet);
241             sc.allocation_method = avdtp_subevent_signaling_media_codec_sbc_configuration_get_allocation_method(packet) - 1;
242             sc.max_bitpool_value = avdtp_subevent_signaling_media_codec_sbc_configuration_get_max_bitpool_value(packet);
243             sc.channel_mode = avdtp_subevent_signaling_media_codec_sbc_configuration_get_channel_mode(packet);
244             // TODO: deal with reconfigure: avdtp_subevent_signaling_media_codec_sbc_configuration_get_reconfigure(packet);
245             break;
246         }
247         case AVDTP_SUBEVENT_STREAMING_CAN_SEND_MEDIA_PACKET_NOW:
248             cid = avdtp_subevent_streaming_can_send_media_packet_now_get_avdtp_cid(packet);
249             a2dp_streaming_emit_can_send_media_packet_now(a2dp_source_context.a2dp_callback, cid, 0);
250             break;
251 
252         case AVDTP_SUBEVENT_STREAMING_CONNECTION_ESTABLISHED:
253             avdtp_subevent_streaming_connection_established_get_bd_addr(packet, address);
254             status = avdtp_subevent_streaming_connection_established_get_status(packet);
255             cid = avdtp_subevent_streaming_connection_established_get_avdtp_cid(packet);
256             remote_seid = avdtp_subevent_streaming_connection_established_get_remote_seid(packet);
257             local_seid  = avdtp_subevent_streaming_connection_established_get_local_seid(packet);
258             if (status != 0){
259                 log_info("AVDTP_SUBEVENT_STREAMING_CONNECTION could not be established, status %d ---", status);
260                 a2dp_streaming_emit_connection_established(a2dp_source_context.a2dp_callback, cid, address, local_seid, remote_seid, status);
261                 break;
262             }
263 
264             app_state = A2DP_STREAMING_OPENED;
265             a2dp_streaming_emit_connection_established(a2dp_source_context.a2dp_callback, cid, address, local_seid, remote_seid, 0);
266             log_info("AVDTP_SUBEVENT_STREAMING_CONNECTION_ESTABLISHED --- avdtp_cid 0x%02x, local seid %d, remote seid %d", cid, local_seid, remote_seid);
267             break;
268 
269         case AVDTP_SUBEVENT_SIGNALING_ACCEPT:
270             // TODO check cid
271             signal_identifier = avdtp_subevent_signaling_accept_get_signal_identifier(packet);
272             cid = avdtp_subevent_signaling_accept_get_avdtp_cid(packet);
273             log_info("Accepted %d", signal_identifier);
274 
275             switch (app_state){
276                 case A2DP_W2_DISCOVER_SEPS:
277                     app_state = A2DP_W2_GET_ALL_CAPABILITIES;
278 
279                     sc.active_remote_sep = avdtp_source_remote_sep(cid, next_remote_sep_index_to_query++);
280                     if (!sc.active_remote_sep) {
281                         app_state = A2DP_IDLE;
282                         a2dp_streaming_emit_connection_established(a2dp_source_context.a2dp_callback, cid, sc.remote_addr, 0, 0, AVDTP_SEID_DOES_NOT_EXIST);
283                         break;
284                     }
285                     // printf("Query get caps for seid %d\n", sc.active_remote_sep->seid);
286                     avdtp_source_get_capabilities(cid, sc.active_remote_sep->seid);
287                     break;
288                 case A2DP_W2_GET_CAPABILITIES:
289                 case A2DP_W2_GET_ALL_CAPABILITIES:
290                     if (next_remote_sep_index_to_query < avdtp_source_remote_seps_num(cid)){
291                         sc.active_remote_sep = avdtp_source_remote_sep(cid, next_remote_sep_index_to_query++);
292                         // printf("Query get caps for seid %d\n", sc.active_remote_sep->seid);
293                         avdtp_source_get_capabilities(cid, sc.active_remote_sep->seid);
294                     } else {
295                         // printf("No more remote seps found\n");
296                         app_state = A2DP_IDLE;
297                         a2dp_streaming_emit_connection_established(a2dp_source_context.a2dp_callback, cid, sc.remote_addr, 0, 0, AVDTP_SEID_DOES_NOT_EXIST);
298                     }
299                     break;
300                 case A2DP_W2_SET_CONFIGURATION:{
301                     if (!sc.local_stream_endpoint) return;
302                     app_state = A2DP_W2_GET_CONFIGURATION;
303                     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);
304                     break;
305                 }
306                 case A2DP_W2_GET_CONFIGURATION:
307                     app_state = A2DP_W2_OPEN_STREAM_WITH_SEID;
308                     avdtp_source_get_configuration(cid, sc.active_remote_sep->seid);
309                     break;
310                 case A2DP_W2_OPEN_STREAM_WITH_SEID:{
311                     app_state = A2DP_W4_OPEN_STREAM_WITH_SEID;
312                     btstack_sbc_encoder_init(&sc.sbc_encoder_state, SBC_MODE_STANDARD,
313                         sc.block_length, sc.subbands,
314                         sc.allocation_method, sc.sampling_frequency,
315                         sc.max_bitpool_value,
316                         sc.channel_mode);
317                     avdtp_source_open_stream(cid, avdtp_stream_endpoint_seid(sc.local_stream_endpoint), sc.active_remote_sep->seid);
318                     break;
319                 }
320                 case A2DP_STREAMING_OPENED:
321                     if (!a2dp_source_context.a2dp_callback) return;
322                     switch (signal_identifier){
323                         case  AVDTP_SI_START:{
324                             uint8_t event[6];
325                             int pos = 0;
326                             event[pos++] = HCI_EVENT_A2DP_META;
327                             event[pos++] = sizeof(event) - 2;
328                             event[pos++] = A2DP_SUBEVENT_STREAM_STARTED;
329                             little_endian_store_16(event, pos, cid);
330                             pos += 2;
331                             event[pos++] = avdtp_stream_endpoint_seid(sc.local_stream_endpoint);
332                             (*a2dp_source_context.a2dp_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
333                             break;
334                         }
335                         case AVDTP_SI_SUSPEND:{
336                             uint8_t event[6];
337                             int pos = 0;
338                             event[pos++] = HCI_EVENT_A2DP_META;
339                             event[pos++] = sizeof(event) - 2;
340                             event[pos++] = A2DP_SUBEVENT_STREAM_SUSPENDED;
341                             little_endian_store_16(event, pos, cid);
342                             pos += 2;
343                             event[pos++] = avdtp_stream_endpoint_seid(sc.local_stream_endpoint);
344                             (*a2dp_source_context.a2dp_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
345                             break;
346                         }
347                         case AVDTP_SI_ABORT:
348                         case AVDTP_SI_CLOSE:{
349                             uint8_t event[6];
350                             int pos = 0;
351                             event[pos++] = HCI_EVENT_A2DP_META;
352                             event[pos++] = sizeof(event) - 2;
353                             event[pos++] = A2DP_SUBEVENT_STREAM_STOPPED;
354                             little_endian_store_16(event, pos, cid);
355                             pos += 2;
356                             log_info("send A2DP_SUBEVENT_STREAM_RELEASED to app");
357                             event[pos++] = avdtp_stream_endpoint_seid(sc.local_stream_endpoint);
358                             (*a2dp_source_context.a2dp_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
359                             break;
360                         }
361                         default:
362                             break;
363                     }
364                     break;
365                 default:
366                     app_state = A2DP_IDLE;
367                     break;
368             }
369 
370             break;
371         case AVDTP_SUBEVENT_SIGNALING_REJECT:
372             app_state = A2DP_IDLE;
373             signal_identifier = avdtp_subevent_signaling_reject_get_signal_identifier(packet);
374             log_info("Rejected %d", signal_identifier);
375             break;
376         case AVDTP_SUBEVENT_SIGNALING_GENERAL_REJECT:
377             app_state = A2DP_IDLE;
378             signal_identifier = avdtp_subevent_signaling_general_reject_get_signal_identifier(packet);
379             log_info("Rejected %d", signal_identifier);
380             break;
381         case AVDTP_SUBEVENT_SIGNALING_CONNECTION_RELEASED:{
382             app_state = A2DP_IDLE;
383             uint8_t event[6];
384             int pos = 0;
385             event[pos++] = HCI_EVENT_A2DP_META;
386             event[pos++] = sizeof(event) - 2;
387             event[pos++] = A2DP_SUBEVENT_SIGNALING_CONNECTION_RELEASED;
388             little_endian_store_16(event, pos, avdtp_subevent_streaming_connection_released_get_avdtp_cid(packet));
389             pos += 2;
390             event[pos++] = avdtp_subevent_streaming_connection_released_get_local_seid(packet);
391             (*a2dp_source_context.a2dp_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
392             break;
393         }
394         case AVDTP_SUBEVENT_STREAMING_CONNECTION_RELEASED:{
395             app_state = A2DP_IDLE;
396             uint8_t event[6];
397             int pos = 0;
398             event[pos++] = HCI_EVENT_A2DP_META;
399             event[pos++] = sizeof(event) - 2;
400             event[pos++] = A2DP_SUBEVENT_STREAM_RELEASED;
401             little_endian_store_16(event, pos, avdtp_subevent_streaming_connection_released_get_avdtp_cid(packet));
402             pos += 2;
403             event[pos++] = avdtp_subevent_streaming_connection_released_get_local_seid(packet);
404             (*a2dp_source_context.a2dp_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
405             break;
406         }
407         default:
408             app_state = A2DP_IDLE;
409             log_info("not implemented");
410             break;
411     }
412 }
413 void a2dp_source_register_packet_handler(btstack_packet_handler_t callback){
414     if (callback == NULL){
415         log_error("a2dp_source_register_packet_handler called with NULL callback");
416         return;
417     }
418     avdtp_source_register_packet_handler(&packet_handler);
419     a2dp_source_context.a2dp_callback = callback;
420 }
421 
422 void a2dp_source_init(void){
423     avdtp_source_init(&a2dp_source_context);
424     l2cap_register_service(&packet_handler, BLUETOOTH_PROTOCOL_AVDTP, 0xffff, LEVEL_0);
425 }
426 
427 avdtp_stream_endpoint_t * a2dp_source_create_stream_endpoint(avdtp_media_type_t media_type, avdtp_media_codec_type_t media_codec_type,
428     uint8_t * codec_capabilities, uint16_t codec_capabilities_len,
429     uint8_t * media_codec_info, uint16_t media_codec_info_len){
430     avdtp_stream_endpoint_t * local_stream_endpoint = avdtp_source_create_stream_endpoint(AVDTP_SOURCE, media_type);
431     if (!local_stream_endpoint){
432         return NULL;
433     }
434     avdtp_source_register_media_transport_category(avdtp_stream_endpoint_seid(local_stream_endpoint));
435     avdtp_source_register_media_codec_category(avdtp_stream_endpoint_seid(local_stream_endpoint), media_type, media_codec_type,
436         codec_capabilities, codec_capabilities_len);
437     local_stream_endpoint->remote_configuration.media_codec.media_codec_information     = media_codec_info;
438     local_stream_endpoint->remote_configuration.media_codec.media_codec_information_len = media_codec_info_len;
439 
440     return local_stream_endpoint;
441 }
442 
443 uint8_t a2dp_source_establish_stream(bd_addr_t remote_addr, uint8_t loc_seid, uint16_t * a2dp_cid){
444     sc.local_stream_endpoint = avdtp_stream_endpoint_for_seid(loc_seid, &a2dp_source_context);
445     if (!sc.local_stream_endpoint){
446         log_error(" no local_stream_endpoint for seid %d", loc_seid);
447         return AVDTP_SEID_DOES_NOT_EXIST;
448     }
449     memcpy(sc.remote_addr, remote_addr, 6);
450     return avdtp_source_connect(remote_addr, a2dp_cid);
451 }
452 
453 uint8_t a2dp_source_disconnect(uint16_t a2dp_cid){
454     return avdtp_disconnect(a2dp_cid, &a2dp_source_context);
455 }
456 
457 uint8_t a2dp_source_start_stream(uint16_t a2dp_cid, uint8_t local_seid){
458     return avdtp_start_stream(a2dp_cid, local_seid, &a2dp_source_context);
459 }
460 
461 uint8_t a2dp_source_pause_stream(uint16_t a2dp_cid, uint8_t local_seid){
462     return avdtp_suspend_stream(a2dp_cid, local_seid, &a2dp_source_context);
463 }
464 
465 static void a2dp_source_setup_media_header(uint8_t * media_packet, int size, int *offset, uint8_t marker, uint16_t sequence_number){
466     if (size < AVDTP_MEDIA_PAYLOAD_HEADER_SIZE){
467         log_error("small outgoing buffer");
468         return;
469     }
470 
471     uint8_t  rtp_version = 2;
472     uint8_t  padding = 0;
473     uint8_t  extension = 0;
474     uint8_t  csrc_count = 0;
475     uint8_t  payload_type = 0x60;
476     // uint16_t sequence_number = stream_endpoint->sequence_number;
477     uint32_t timestamp = btstack_run_loop_get_time_ms();
478     uint32_t ssrc = 0x11223344;
479 
480     // rtp header (min size 12B)
481     int pos = 0;
482     // int mtu = l2cap_get_remote_mtu_for_local_cid(stream_endpoint->l2cap_media_cid);
483 
484     media_packet[pos++] = (rtp_version << 6) | (padding << 5) | (extension << 4) | csrc_count;
485     media_packet[pos++] = (marker << 1) | payload_type;
486     big_endian_store_16(media_packet, pos, sequence_number);
487     pos += 2;
488     big_endian_store_32(media_packet, pos, timestamp);
489     pos += 4;
490     big_endian_store_32(media_packet, pos, ssrc); // only used for multicast
491     pos += 4;
492     *offset = pos;
493 }
494 
495 void a2dp_source_stream_endpoint_request_can_send_now(uint16_t a2dp_cid, uint8_t local_seid){
496     avdtp_stream_endpoint_t * stream_endpoint = avdtp_stream_endpoint_for_seid(local_seid, &a2dp_source_context);
497     if (!stream_endpoint) {
498         log_error("A2DP source: no stream_endpoint with seid %d", local_seid);
499         return;
500     }
501     if (a2dp_source_context.avdtp_cid != a2dp_cid){
502         log_error("A2DP source: a2dp cid 0x%02x not known, expected 0x%02x", a2dp_cid, a2dp_source_context.avdtp_cid);
503         return;
504     }
505     stream_endpoint->send_stream = 1;
506     avdtp_request_can_send_now_initiator(stream_endpoint->connection, stream_endpoint->l2cap_media_cid);
507 }
508 
509 int a2dp_max_media_payload_size(uint16_t a2dp_cid, uint8_t local_seid){
510     avdtp_stream_endpoint_t * stream_endpoint = avdtp_stream_endpoint_for_seid(local_seid, &a2dp_source_context);
511     if (!stream_endpoint) {
512         log_error("A2DP source: no stream_endpoint with seid %d", local_seid);
513         return 0;
514     }
515     if (a2dp_source_context.avdtp_cid != a2dp_cid){
516         log_error("A2DP source: a2dp cid 0x%02x not known, expected 0x%02x", a2dp_cid, a2dp_source_context.avdtp_cid);
517         return 0;
518     }
519 
520     if (stream_endpoint->l2cap_media_cid == 0){
521         log_error("A2DP source: no media connection for seid %d", local_seid);
522         return 0;
523     }
524     return l2cap_get_remote_mtu_for_local_cid(stream_endpoint->l2cap_media_cid) - AVDTP_MEDIA_PAYLOAD_HEADER_SIZE;
525 }
526 
527 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){
528     if (size < num_bytes_to_copy + 1){
529         log_error("small outgoing buffer: buffer size %u, but need %u", size, num_bytes_to_copy + 1);
530         return;
531     }
532 
533     int pos = *offset;
534     media_packet[pos++] = num_frames; // (fragmentation << 7) | (starting_packet << 6) | (last_packet << 5) | num_frames;
535     memcpy(media_packet + pos, storage, num_bytes_to_copy);
536     pos += num_bytes_to_copy;
537     *offset = pos;
538 }
539 
540 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){
541     avdtp_stream_endpoint_t * stream_endpoint = avdtp_stream_endpoint_for_seid(local_seid, &a2dp_source_context);
542     if (!stream_endpoint) {
543         log_error("A2DP source: no stream_endpoint with seid %d", local_seid);
544         return 0;
545     }
546     if (a2dp_source_context.avdtp_cid != a2dp_cid){
547         log_error("A2DP source: a2dp cid 0x%02x not known, expected 0x%02x", a2dp_cid, a2dp_source_context.avdtp_cid);
548         return 0;
549     }
550 
551     if (stream_endpoint->l2cap_media_cid == 0){
552         log_error("A2DP source: no media connection for seid %d", local_seid);
553         return 0;
554     }
555 
556     int size = l2cap_get_remote_mtu_for_local_cid(stream_endpoint->l2cap_media_cid);
557     int offset = 0;
558 
559     l2cap_reserve_packet_buffer();
560     uint8_t * media_packet = l2cap_get_outgoing_buffer();
561     //int size = l2cap_get_remote_mtu_for_local_cid(stream_endpoint->l2cap_media_cid);
562     a2dp_source_setup_media_header(media_packet, size, &offset, marker, stream_endpoint->sequence_number);
563     a2dp_source_copy_media_payload(media_packet, size, &offset, storage, num_bytes_to_copy, num_frames);
564     stream_endpoint->sequence_number++;
565     l2cap_send_prepared(stream_endpoint->l2cap_media_cid, offset);
566     return size;
567 }
568