xref: /btstack/src/classic/a2dp_source.c (revision 64697164ef72f7897f172a22b7b13afea33d105c)
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 void packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
165     UNUSED(channel);
166     UNUSED(size);
167 
168     uint8_t signal_identifier;
169     uint8_t status;
170     uint8_t local_seid;
171     uint8_t remote_seid;
172     uint16_t cid;
173     bd_addr_t address;
174 
175     if (packet_type != HCI_EVENT_PACKET) return;
176     if (hci_event_packet_get_type(packet) != HCI_EVENT_AVDTP_META) return;
177 
178     switch (packet[2]){
179         case AVDTP_SUBEVENT_SIGNALING_CONNECTION_ESTABLISHED:{
180             avdtp_subevent_signaling_connection_established_get_bd_addr(packet, sc.remote_addr);
181             cid = avdtp_subevent_signaling_connection_established_get_avdtp_cid(packet);
182             status = avdtp_subevent_signaling_connection_established_get_status(packet);
183 
184             if (status != 0){
185                 log_info("AVDTP_SUBEVENT_SIGNALING_CONNECTION failed status %d ---", status);
186                 a2dp_streaming_emit_connection_established(a2dp_source_context.a2dp_callback, cid, sc.remote_addr, 0, 0, status);
187                 break;
188             }
189 
190             sc.active_remote_sep = NULL;
191             sc.active_remote_sep_index = 0;
192             uint8_t event[11];
193             int pos = 0;
194             event[pos++] = HCI_EVENT_A2DP_META;
195             event[pos++] = sizeof(event) - 2;
196             event[pos++] = A2DP_SUBEVENT_SIGNALING_CONNECTION_ESTABLISHED;
197             little_endian_store_16(event, pos, cid);
198             pos += 2;
199             reverse_bd_addr(event+pos, sc.remote_addr);
200             pos += 6;
201             (*a2dp_source_context.a2dp_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
202 
203             log_info("A2DP_SUBEVENT_SIGNALING_CONNECTION established avdtp_cid 0x%02x ---", a2dp_source_context.avdtp_cid);
204 
205             app_state = A2DP_W2_DISCOVER_SEPS;
206             avdtp_source_discover_stream_endpoints(cid);
207             break;
208         }
209         case AVDTP_SUBEVENT_SIGNALING_SEP_FOUND:
210             break;
211 
212         case AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CAPABILITY:{
213             log_info("A2DP received SBC capability.");
214             if (!sc.local_stream_endpoint) {
215                 printf("local seid %d \n", avdtp_subevent_signaling_media_codec_sbc_capability_get_local_seid(packet));
216                 return;
217             }
218             log_info("A2DP received SBC capability.");
219 
220             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));
221             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));
222             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));
223             uint8_t subbands = avdtp_choose_sbc_subbands(sc.local_stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_subbands_bitmap(packet));
224 
225             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));
226             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));
227             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));
228 
229             sc.local_stream_endpoint->remote_configuration.media_codec.media_codec_information[0] = (sampling_frequency << 4) | channel_mode;
230             sc.local_stream_endpoint->remote_configuration.media_codec.media_codec_information[1] = (block_length << 4) | (subbands << 2) | allocation_method;
231             sc.local_stream_endpoint->remote_configuration.media_codec.media_codec_information[2] = min_bitpool_value;
232             sc.local_stream_endpoint->remote_configuration.media_codec.media_codec_information[3] = max_bitpool_value;
233 
234             sc.local_stream_endpoint->remote_configuration_bitmap = store_bit16(sc.local_stream_endpoint->remote_configuration_bitmap, AVDTP_MEDIA_CODEC, 1);
235             sc.local_stream_endpoint->remote_configuration.media_codec.media_type = AVDTP_AUDIO;
236             sc.local_stream_endpoint->remote_configuration.media_codec.media_codec_type = AVDTP_CODEC_SBC;
237 
238             app_state = A2DP_W2_SET_CONFIGURATION;
239             break;
240         }
241         case AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_OTHER_CAPABILITY:
242             log_info("received non SBC codec. not implemented");
243             break;
244 
245         case AVDTP_SUBEVENT_SIGNALING_MEDIA_TRANSPORT_CAPABILITY:
246             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));
247             break;
248         case AVDTP_SUBEVENT_SIGNALING_REPORTING_CAPABILITY:
249             log_info("received, but not forwarded: AVDTP_SUBEVENT_SIGNALING_REPORTING_CAPABILITY, remote seid %d\n", avdtp_subevent_signaling_reporting_capability_get_remote_seid(packet));
250             break;
251         case AVDTP_SUBEVENT_SIGNALING_DELAY_REPORTING_CAPABILITY:
252             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));
253             break;
254         case AVDTP_SUBEVENT_SIGNALING_RECOVERY_CAPABILITY:
255             log_info("received, but not forwarded: AVDTP_SUBEVENT_SIGNALING_RECOVERY_CAPABILITY, remote seid %d\n", avdtp_subevent_signaling_recovery_capability_get_remote_seid(packet));
256             break;
257         case AVDTP_SUBEVENT_SIGNALING_CONTENT_PROTECTION_CAPABILITY:
258             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));
259             break;
260         case AVDTP_SUBEVENT_SIGNALING_HEADER_COMPRESSION_CAPABILITY:
261             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));
262             break;
263         case AVDTP_SUBEVENT_SIGNALING_MULTIPLEXING_CAPABILITY:
264             log_info("received, but not forwarded: AVDTP_SUBEVENT_SIGNALING_MULTIPLEXING_CAPABILITY, remote seid %d\n", avdtp_subevent_signaling_multiplexing_capability_get_remote_seid(packet));
265             break;
266         case AVDTP_SUBEVENT_SIGNALING_CAPABILITY_DONE:
267             break;
268 
269         case AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CONFIGURATION:{
270             // TODO check cid
271             sc.sampling_frequency = avdtp_subevent_signaling_media_codec_sbc_configuration_get_sampling_frequency(packet);
272             sc.block_length = avdtp_subevent_signaling_media_codec_sbc_configuration_get_block_length(packet);
273             sc.subbands = avdtp_subevent_signaling_media_codec_sbc_configuration_get_subbands(packet);
274             sc.allocation_method = avdtp_subevent_signaling_media_codec_sbc_configuration_get_allocation_method(packet) - 1;
275             sc.max_bitpool_value = avdtp_subevent_signaling_media_codec_sbc_configuration_get_max_bitpool_value(packet);
276             sc.channel_mode = avdtp_subevent_signaling_media_codec_sbc_configuration_get_channel_mode(packet);
277             // TODO: deal with reconfigure: avdtp_subevent_signaling_media_codec_sbc_configuration_get_reconfigure(packet);
278             log_info("A2DP received SBC Config: sample rate %u, max bitpool %u.", sc.sampling_frequency, sc.max_bitpool_value);
279             app_state = A2DP_W2_OPEN_STREAM_WITH_SEID;
280             a2dp_signaling_emit_media_codec_sbc(a2dp_source_context.a2dp_callback, packet, size);
281             break;
282         }
283 
284         case AVDTP_SUBEVENT_STREAMING_CAN_SEND_MEDIA_PACKET_NOW:
285             cid = avdtp_subevent_streaming_can_send_media_packet_now_get_avdtp_cid(packet);
286             a2dp_streaming_emit_can_send_media_packet_now(a2dp_source_context.a2dp_callback, cid, 0);
287             break;
288 
289         case AVDTP_SUBEVENT_STREAMING_CONNECTION_ESTABLISHED:
290             avdtp_subevent_streaming_connection_established_get_bd_addr(packet, address);
291             status = avdtp_subevent_streaming_connection_established_get_status(packet);
292             cid = avdtp_subevent_streaming_connection_established_get_avdtp_cid(packet);
293             remote_seid = avdtp_subevent_streaming_connection_established_get_remote_seid(packet);
294             local_seid  = avdtp_subevent_streaming_connection_established_get_local_seid(packet);
295             if (status != 0){
296                 log_info("AVDTP_SUBEVENT_STREAMING_CONNECTION could not be established, status %d ---", status);
297                 a2dp_streaming_emit_connection_established(a2dp_source_context.a2dp_callback, cid, address, local_seid, remote_seid, status);
298                 break;
299             }
300 
301             app_state = A2DP_STREAMING_OPENED;
302             a2dp_streaming_emit_connection_established(a2dp_source_context.a2dp_callback, cid, address, local_seid, remote_seid, 0);
303             log_info("AVDTP_SUBEVENT_STREAMING_CONNECTION_ESTABLISHED --- avdtp_cid 0x%02x, local seid %d, remote seid %d", cid, local_seid, remote_seid);
304             break;
305 
306         case AVDTP_SUBEVENT_SIGNALING_ACCEPT:
307             // TODO check cid
308             signal_identifier = avdtp_subevent_signaling_accept_get_signal_identifier(packet);
309             cid = avdtp_subevent_signaling_accept_get_avdtp_cid(packet);
310             log_info("A2DP Accepted %d, state %d", signal_identifier, app_state);
311 
312             switch (app_state){
313                 case A2DP_W2_DISCOVER_SEPS:
314                 case A2DP_W2_GET_CAPABILITIES:
315                 case A2DP_W2_GET_ALL_CAPABILITIES:
316                     app_state = A2DP_W2_GET_ALL_CAPABILITIES;
317                     sc.active_remote_sep = avdtp_source_remote_sep(cid, sc.active_remote_sep_index++);
318                     if (!sc.active_remote_sep) {
319                         app_state = A2DP_IDLE;
320                         a2dp_streaming_emit_connection_established(a2dp_source_context.a2dp_callback, cid, sc.remote_addr, 0, 0, AVDTP_SEID_DOES_NOT_EXIST);
321                         break;
322                     }
323                     avdtp_source_get_capabilities(cid, sc.active_remote_sep->seid);
324                     break;
325                 case A2DP_W2_SET_CONFIGURATION:{
326                     if (!sc.local_stream_endpoint) return;
327                     app_state = A2DP_IDLE;
328                     log_info("A2DP initiate set configuration locally and wait for response ... ");
329                     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);
330                     break;
331                 }
332                 case A2DP_W2_OPEN_STREAM_WITH_SEID:{
333                     log_info("A2DP open stream ");
334                     app_state = A2DP_W4_OPEN_STREAM_WITH_SEID;
335                     avdtp_source_open_stream(cid, avdtp_stream_endpoint_seid(sc.local_stream_endpoint), sc.active_remote_sep->seid);
336                     break;
337                 }
338                 case A2DP_STREAMING_OPENED:
339                     if (!a2dp_source_context.a2dp_callback) return;
340                     switch (signal_identifier){
341                         case  AVDTP_SI_START:{
342                             uint8_t event[6];
343                             int pos = 0;
344                             event[pos++] = HCI_EVENT_A2DP_META;
345                             event[pos++] = sizeof(event) - 2;
346                             event[pos++] = A2DP_SUBEVENT_STREAM_STARTED;
347                             little_endian_store_16(event, pos, cid);
348                             pos += 2;
349                             event[pos++] = avdtp_stream_endpoint_seid(sc.local_stream_endpoint);
350                             (*a2dp_source_context.a2dp_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
351                             break;
352                         }
353                         case AVDTP_SI_SUSPEND:{
354                             uint8_t event[6];
355                             int pos = 0;
356                             event[pos++] = HCI_EVENT_A2DP_META;
357                             event[pos++] = sizeof(event) - 2;
358                             event[pos++] = A2DP_SUBEVENT_STREAM_SUSPENDED;
359                             little_endian_store_16(event, pos, cid);
360                             pos += 2;
361                             event[pos++] = avdtp_stream_endpoint_seid(sc.local_stream_endpoint);
362                             (*a2dp_source_context.a2dp_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
363                             break;
364                         }
365                         case AVDTP_SI_ABORT:
366                         case AVDTP_SI_CLOSE:{
367                             uint8_t event[6];
368                             int pos = 0;
369                             event[pos++] = HCI_EVENT_A2DP_META;
370                             event[pos++] = sizeof(event) - 2;
371                             event[pos++] = A2DP_SUBEVENT_STREAM_STOPPED;
372                             little_endian_store_16(event, pos, cid);
373                             pos += 2;
374                             log_info("send A2DP_SUBEVENT_STREAM_RELEASED to app");
375                             event[pos++] = avdtp_stream_endpoint_seid(sc.local_stream_endpoint);
376                             (*a2dp_source_context.a2dp_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
377                             break;
378                         }
379                         default:
380                             break;
381                     }
382                     break;
383                 default:
384                     app_state = A2DP_IDLE;
385                     break;
386             }
387 
388             break;
389         case AVDTP_SUBEVENT_SIGNALING_REJECT:
390             app_state = A2DP_IDLE;
391             signal_identifier = avdtp_subevent_signaling_reject_get_signal_identifier(packet);
392             log_info("A2DP Rejected %d", signal_identifier);
393             break;
394         case AVDTP_SUBEVENT_SIGNALING_GENERAL_REJECT:
395             app_state = A2DP_IDLE;
396             signal_identifier = avdtp_subevent_signaling_general_reject_get_signal_identifier(packet);
397             log_info("A2DP Rejected %d", signal_identifier);
398             break;
399         case AVDTP_SUBEVENT_SIGNALING_CONNECTION_RELEASED:{
400             app_state = A2DP_IDLE;
401             uint8_t event[6];
402             int pos = 0;
403             event[pos++] = HCI_EVENT_A2DP_META;
404             event[pos++] = sizeof(event) - 2;
405             event[pos++] = A2DP_SUBEVENT_SIGNALING_CONNECTION_RELEASED;
406             little_endian_store_16(event, pos, avdtp_subevent_streaming_connection_released_get_avdtp_cid(packet));
407             pos += 2;
408             event[pos++] = avdtp_subevent_streaming_connection_released_get_local_seid(packet);
409             (*a2dp_source_context.a2dp_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
410             break;
411         }
412         case AVDTP_SUBEVENT_STREAMING_CONNECTION_RELEASED:{
413             app_state = A2DP_IDLE;
414             uint8_t event[6];
415             int pos = 0;
416             event[pos++] = HCI_EVENT_A2DP_META;
417             event[pos++] = sizeof(event) - 2;
418             event[pos++] = A2DP_SUBEVENT_STREAM_RELEASED;
419             little_endian_store_16(event, pos, avdtp_subevent_streaming_connection_released_get_avdtp_cid(packet));
420             pos += 2;
421             event[pos++] = avdtp_subevent_streaming_connection_released_get_local_seid(packet);
422             (*a2dp_source_context.a2dp_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
423             break;
424         }
425         default:
426             app_state = A2DP_IDLE;
427             log_info("not implemented");
428             break;
429     }
430 }
431 void a2dp_source_register_packet_handler(btstack_packet_handler_t callback){
432     if (callback == NULL){
433         log_error("a2dp_source_register_packet_handler called with NULL callback");
434         return;
435     }
436     avdtp_source_register_packet_handler(&packet_handler);
437     a2dp_source_context.a2dp_callback = callback;
438 }
439 
440 void a2dp_source_init(void){
441     avdtp_source_init(&a2dp_source_context);
442     l2cap_register_service(&packet_handler, BLUETOOTH_PROTOCOL_AVDTP, 0xffff, LEVEL_0);
443 }
444 
445 avdtp_stream_endpoint_t * a2dp_source_create_stream_endpoint(avdtp_media_type_t media_type, avdtp_media_codec_type_t media_codec_type,
446     uint8_t * codec_capabilities, uint16_t codec_capabilities_len,
447     uint8_t * media_codec_info, uint16_t media_codec_info_len){
448     avdtp_stream_endpoint_t * local_stream_endpoint = avdtp_source_create_stream_endpoint(AVDTP_SOURCE, media_type);
449     if (!local_stream_endpoint){
450         return NULL;
451     }
452     avdtp_source_register_media_transport_category(avdtp_stream_endpoint_seid(local_stream_endpoint));
453     avdtp_source_register_media_codec_category(avdtp_stream_endpoint_seid(local_stream_endpoint), media_type, media_codec_type,
454         codec_capabilities, codec_capabilities_len);
455     local_stream_endpoint->remote_configuration.media_codec.media_codec_information     = media_codec_info;
456     local_stream_endpoint->remote_configuration.media_codec.media_codec_information_len = media_codec_info_len;
457     sc.local_stream_endpoint = local_stream_endpoint;
458     return local_stream_endpoint;
459 }
460 
461 uint8_t a2dp_source_establish_stream(bd_addr_t remote_addr, uint8_t loc_seid, uint16_t * a2dp_cid){
462     sc.local_stream_endpoint = avdtp_stream_endpoint_for_seid(loc_seid, &a2dp_source_context);
463     if (!sc.local_stream_endpoint){
464         log_error(" no local_stream_endpoint for seid %d", loc_seid);
465         return AVDTP_SEID_DOES_NOT_EXIST;
466     }
467     memcpy(sc.remote_addr, remote_addr, 6);
468     return avdtp_source_connect(remote_addr, a2dp_cid);
469 }
470 
471 uint8_t a2dp_source_disconnect(uint16_t a2dp_cid){
472     return avdtp_disconnect(a2dp_cid, &a2dp_source_context);
473 }
474 
475 uint8_t a2dp_source_start_stream(uint16_t a2dp_cid, uint8_t local_seid){
476     return avdtp_start_stream(a2dp_cid, local_seid, &a2dp_source_context);
477 }
478 
479 uint8_t a2dp_source_pause_stream(uint16_t a2dp_cid, uint8_t local_seid){
480     return avdtp_suspend_stream(a2dp_cid, local_seid, &a2dp_source_context);
481 }
482 
483 static void a2dp_source_setup_media_header(uint8_t * media_packet, int size, int *offset, uint8_t marker, uint16_t sequence_number){
484     if (size < AVDTP_MEDIA_PAYLOAD_HEADER_SIZE){
485         log_error("small outgoing buffer");
486         return;
487     }
488 
489     uint8_t  rtp_version = 2;
490     uint8_t  padding = 0;
491     uint8_t  extension = 0;
492     uint8_t  csrc_count = 0;
493     uint8_t  payload_type = 0x60;
494     // uint16_t sequence_number = stream_endpoint->sequence_number;
495     uint32_t timestamp = btstack_run_loop_get_time_ms();
496     uint32_t ssrc = 0x11223344;
497 
498     // rtp header (min size 12B)
499     int pos = 0;
500     // int mtu = l2cap_get_remote_mtu_for_local_cid(stream_endpoint->l2cap_media_cid);
501 
502     media_packet[pos++] = (rtp_version << 6) | (padding << 5) | (extension << 4) | csrc_count;
503     media_packet[pos++] = (marker << 1) | payload_type;
504     big_endian_store_16(media_packet, pos, sequence_number);
505     pos += 2;
506     big_endian_store_32(media_packet, pos, timestamp);
507     pos += 4;
508     big_endian_store_32(media_packet, pos, ssrc); // only used for multicast
509     pos += 4;
510     *offset = pos;
511 }
512 
513 void a2dp_source_stream_endpoint_request_can_send_now(uint16_t a2dp_cid, uint8_t local_seid){
514     avdtp_stream_endpoint_t * stream_endpoint = avdtp_stream_endpoint_for_seid(local_seid, &a2dp_source_context);
515     if (!stream_endpoint) {
516         log_error("A2DP source: no stream_endpoint with seid %d", local_seid);
517         return;
518     }
519     if (a2dp_source_context.avdtp_cid != a2dp_cid){
520         log_error("A2DP source: a2dp cid 0x%02x not known, expected 0x%02x", a2dp_cid, a2dp_source_context.avdtp_cid);
521         return;
522     }
523     stream_endpoint->send_stream = 1;
524     avdtp_request_can_send_now_initiator(stream_endpoint->connection, stream_endpoint->l2cap_media_cid);
525 }
526 
527 int a2dp_max_media_payload_size(uint16_t a2dp_cid, uint8_t local_seid){
528     avdtp_stream_endpoint_t * stream_endpoint = avdtp_stream_endpoint_for_seid(local_seid, &a2dp_source_context);
529     if (!stream_endpoint) {
530         log_error("A2DP source: no stream_endpoint with seid %d", local_seid);
531         return 0;
532     }
533     if (a2dp_source_context.avdtp_cid != a2dp_cid){
534         log_error("A2DP source: a2dp cid 0x%02x not known, expected 0x%02x", a2dp_cid, a2dp_source_context.avdtp_cid);
535         return 0;
536     }
537 
538     if (stream_endpoint->l2cap_media_cid == 0){
539         log_error("A2DP source: no media connection for seid %d", local_seid);
540         return 0;
541     }
542     return l2cap_get_remote_mtu_for_local_cid(stream_endpoint->l2cap_media_cid) - AVDTP_MEDIA_PAYLOAD_HEADER_SIZE;
543 }
544 
545 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){
546     if (size < num_bytes_to_copy + 1){
547         log_error("small outgoing buffer: buffer size %u, but need %u", size, num_bytes_to_copy + 1);
548         return;
549     }
550 
551     int pos = *offset;
552     media_packet[pos++] = num_frames; // (fragmentation << 7) | (starting_packet << 6) | (last_packet << 5) | num_frames;
553     memcpy(media_packet + pos, storage, num_bytes_to_copy);
554     pos += num_bytes_to_copy;
555     *offset = pos;
556 }
557 
558 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){
559     avdtp_stream_endpoint_t * stream_endpoint = avdtp_stream_endpoint_for_seid(local_seid, &a2dp_source_context);
560     if (!stream_endpoint) {
561         log_error("A2DP source: no stream_endpoint with seid %d", local_seid);
562         return 0;
563     }
564     if (a2dp_source_context.avdtp_cid != a2dp_cid){
565         log_error("A2DP source: a2dp cid 0x%02x not known, expected 0x%02x", a2dp_cid, a2dp_source_context.avdtp_cid);
566         return 0;
567     }
568 
569     if (stream_endpoint->l2cap_media_cid == 0){
570         log_error("A2DP source: no media connection for seid %d", local_seid);
571         return 0;
572     }
573 
574     int size = l2cap_get_remote_mtu_for_local_cid(stream_endpoint->l2cap_media_cid);
575     int offset = 0;
576 
577     l2cap_reserve_packet_buffer();
578     uint8_t * media_packet = l2cap_get_outgoing_buffer();
579     //int size = l2cap_get_remote_mtu_for_local_cid(stream_endpoint->l2cap_media_cid);
580     a2dp_source_setup_media_header(media_packet, size, &offset, marker, stream_endpoint->sequence_number);
581     a2dp_source_copy_media_payload(media_packet, size, &offset, storage, num_bytes_to_copy, num_frames);
582     stream_endpoint->sequence_number++;
583     l2cap_send_prepared(stream_endpoint->l2cap_media_cid, offset);
584     return size;
585 }
586