xref: /btstack/src/classic/avdtp_util.c (revision 6d34f98e0c6a035be904a5ac00e86a7b4f285631)
1 /*
2  * Copyright (C) 2016 BlueKitchen GmbH
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the copyright holders nor the names of
14  *    contributors may be used to endorse or promote products derived
15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
17  *    personal benefit and not for any commercial purpose or for
18  *    monetary gain.
19  *
20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
24  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 #define BTSTACK_FILE__ "avdtp_util.c"
39 
40 #include <stdint.h>
41 #include <string.h>
42 
43 #include "btstack.h"
44 #include "avdtp.h"
45 #include "avdtp_util.h"
46 
47 #define MAX_MEDIA_CODEC_INFORMATION_LENGTH 100
48 
49 
50 /*
51 
52  List of AVDTP_SUBEVENTs sorted by packet handler
53 
54 
55 Sink + Source:
56 - AVDTP_SUBEVENT_SIGNALING_CONNECTION_ESTABLISHED
57 - AVDTP_SUBEVENT_SIGNALING_CONNECTION_RELEASED
58 - AVDTP_SUBEVENT_SIGNALING_SEP_FOUND
59 - AVDTP_SUBEVENT_SIGNALING_ACCEPT
60 - AVDTP_SUBEVENT_SIGNALING_REJECT
61 - AVDTP_SUBEVENT_SIGNALING_GENERAL_REJECT
62 - AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CAPABILITY
63 - AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_OTHER_CAPABILITY
64 - AVDTP_SUBEVENT_SIGNALING_MEDIA_TRANSPORT_CAPABILITY
65 - AVDTP_SUBEVENT_SIGNALING_REPORTING_CAPABILITY
66 - AVDTP_SUBEVENT_SIGNALING_RECOVERY_CAPABILITY
67 - AVDTP_SUBEVENT_SIGNALING_CONTENT_PROTECTION_CAPABILITY
68 - AVDTP_SUBEVENT_SIGNALING_MULTIPLEXING_CAPABILITY
69 - AVDTP_SUBEVENT_SIGNALING_DELAY_REPORTING_CAPABILITY
70 - AVDTP_SUBEVENT_SIGNALING_HEADER_COMPRESSION_CAPABILITY
71 - AVDTP_SUBEVENT_SIGNALING_CAPABILITIES_DONE
72 - AVDTP_SUBEVENT_SIGNALING_SEP_DICOVERY_DONE
73 
74 Source:
75  - AVDTP_SUBEVENT_SIGNALING_DELAY_REPORT
76 
77 Sink or Source based on SEP Type:
78 - AVDTP_SUBEVENT_STREAMING_CONNECTION_ESTABLISHED
79 - AVDTP_SUBEVENT_STREAMING_CONNECTION_RELEASED
80 - AVDTP_SUBEVENT_STREAMING_CAN_SEND_MEDIA_PACKET_NOW
81 - AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CONFIGURATION
82 - AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_OTHER_CONFIGURATION
83 
84 */
85 
86 static const char * avdtp_si_name[] = {
87     "ERROR",
88     "AVDTP_SI_DISCOVER",
89     "AVDTP_SI_GET_CAPABILITIES",
90     "AVDTP_SI_SET_CONFIGURATION",
91     "AVDTP_SI_GET_CONFIGURATION",
92     "AVDTP_SI_RECONFIGURE",
93     "AVDTP_SI_OPEN",
94     "AVDTP_SI_START",
95     "AVDTP_SI_CLOSE",
96     "AVDTP_SI_SUSPEND",
97     "AVDTP_SI_ABORT",
98     "AVDTP_SI_SECURITY_CONTROL",
99     "AVDTP_SI_GET_ALL_CAPABILITIES",
100     "AVDTP_SI_DELAY_REPORT"
101 };
102 const char * avdtp_si2str(uint16_t index){
103     if ((index <= 0) || (index >= sizeof(avdtp_si_name)/sizeof(avdtp_si_name[0]) )) return avdtp_si_name[0];
104     return avdtp_si_name[index];
105 }
106 
107 void avdtp_reset_stream_endpoint(avdtp_stream_endpoint_t * stream_endpoint){
108     stream_endpoint->media_con_handle = 0;
109     stream_endpoint->l2cap_media_cid = 0;
110     stream_endpoint->l2cap_reporting_cid = 0;
111     stream_endpoint->l2cap_recovery_cid = 0;
112 
113     stream_endpoint->state = AVDTP_STREAM_ENDPOINT_IDLE;
114     stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_STREAM_CONFIG_IDLE;
115     stream_endpoint->initiator_config_state = AVDTP_INITIATOR_STREAM_CONFIG_IDLE;
116 
117     stream_endpoint->connection = NULL;
118 
119     stream_endpoint->sep.in_use = 0;
120     memset(&stream_endpoint->remote_sep, 0, sizeof(avdtp_sep_t));
121 
122     stream_endpoint->remote_capabilities_bitmap = 0;
123     memset(&stream_endpoint->remote_capabilities, 0, sizeof(avdtp_capabilities_t));
124     stream_endpoint->remote_configuration_bitmap = 0;
125     memset(&stream_endpoint->remote_configuration, 0, sizeof(avdtp_capabilities_t));
126 
127     // temporary SBC config used by A2DP Source
128     memset(stream_endpoint->media_codec_info, 0, 8);
129 
130     stream_endpoint->media_disconnect = 0;
131     stream_endpoint->media_connect = 0;
132     stream_endpoint->start_stream = 0;
133     stream_endpoint->close_stream = 0;
134     stream_endpoint->request_can_send_now = 0;
135     stream_endpoint->abort_stream = 0;
136     stream_endpoint->suspend_stream = 0;
137     stream_endpoint->sequence_number = 0;
138 }
139 
140 int get_bit16(uint16_t bitmap, int position){
141     return (bitmap >> position) & 1;
142 }
143 
144 uint16_t store_bit16(uint16_t bitmap, int position, uint8_t value){
145     if (value){
146         bitmap |= 1 << position;
147     } else {
148         bitmap &= ~ (1 << position);
149     }
150     return bitmap;
151 }
152 
153 avdtp_message_type_t avdtp_get_signaling_packet_type(uint8_t * packet){
154     return (avdtp_message_type_t) (packet[0] & 0x03);
155 }
156 
157 int avdtp_read_signaling_header(avdtp_signaling_packet_t * signaling_header, uint8_t * packet, uint16_t size){
158     int pos = 0;
159     if (size < 2) return pos;
160     signaling_header->transaction_label = packet[pos] >> 4;
161     signaling_header->packet_type = (avdtp_packet_type_t)((packet[pos] >> 2) & 0x03);
162     signaling_header->message_type = (avdtp_message_type_t) (packet[pos] & 0x03);
163     pos++;
164     memset(signaling_header->command, 0, sizeof(signaling_header->command));
165     switch (signaling_header->packet_type){
166         case AVDTP_SINGLE_PACKET:
167             signaling_header->num_packets = 0;
168             signaling_header->offset = 0;
169             signaling_header->size = 0;
170             break;
171         case AVDTP_END_PACKET:
172             signaling_header->num_packets = 0;
173             break;
174         case AVDTP_START_PACKET:
175             signaling_header->num_packets = packet[pos++];
176             signaling_header->size = 0;
177             signaling_header->offset = 0;
178             break;
179         case AVDTP_CONTINUE_PACKET:
180             if (signaling_header->num_packets <= 0) {
181                 log_info("    ERROR: wrong num fragmented packets\n");
182                 break;
183             }
184             signaling_header->num_packets--;
185             break;
186         default:
187             btstack_assert(false);
188             break;
189     }
190     signaling_header->signal_identifier = (avdtp_signal_identifier_t)(packet[pos++] & 0x3f);
191     return pos;
192 }
193 
194 static bool avdtp_is_basic_capability(int service_category){
195     return (AVDTP_MEDIA_TRANSPORT <= service_category) && (service_category <= AVDTP_MEDIA_CODEC);
196 }
197 
198 int avdtp_pack_service_capabilities(uint8_t *buffer, int size, avdtp_capabilities_t caps, avdtp_service_category_t category) {
199     UNUSED(size);
200 
201     int i;
202     // pos = 0 reserved for length
203     int pos = 1;
204     switch(category){
205         case AVDTP_MEDIA_TRANSPORT:
206         case AVDTP_REPORTING:
207         case AVDTP_DELAY_REPORTING:
208             break;
209         case AVDTP_RECOVERY:
210             buffer[pos++] = caps.recovery.recovery_type; // 0x01=RFC2733
211             buffer[pos++] = caps.recovery.maximum_recovery_window_size;
212             buffer[pos++] = caps.recovery.maximum_number_media_packets;
213             break;
214         case AVDTP_CONTENT_PROTECTION:
215             buffer[pos++] = caps.content_protection.cp_type_value_len + 2;
216             big_endian_store_16(buffer, pos, caps.content_protection.cp_type);
217             pos += 2;
218             (void)memcpy(buffer + pos, caps.content_protection.cp_type_value,
219                          caps.content_protection.cp_type_value_len);
220             pos += caps.content_protection.cp_type_value_len;
221             break;
222         case AVDTP_HEADER_COMPRESSION:
223             buffer[pos++] = (caps.header_compression.back_ch << 7) | (caps.header_compression.media << 6) | (caps.header_compression.recovery << 5);
224             break;
225         case AVDTP_MULTIPLEXING:
226             buffer[pos++] = caps.multiplexing_mode.fragmentation << 7;
227             for (i=0; i<caps.multiplexing_mode.transport_identifiers_num; i++){
228                 buffer[pos++] = caps.multiplexing_mode.transport_session_identifiers[i] << 7;
229                 buffer[pos++] = caps.multiplexing_mode.tcid[i] << 7;
230                 // media, reporting. recovery
231             }
232             break;
233         case AVDTP_MEDIA_CODEC:
234             buffer[pos++] = ((uint8_t)caps.media_codec.media_type) << 4;
235             buffer[pos++] = (uint8_t)caps.media_codec.media_codec_type;
236             for (i = 0; i<caps.media_codec.media_codec_information_len; i++){
237                 buffer[pos++] = caps.media_codec.media_codec_information[i];
238             }
239             break;
240         default:
241             break;
242     }
243     buffer[0] = pos - 1; // length
244     return pos;
245 }
246 
247 static int avdtp_unpack_service_capabilities_has_errors(avdtp_connection_t * connection, avdtp_signal_identifier_t signal_identifier, avdtp_service_category_t category, uint8_t cap_len){
248     connection->error_code = 0;
249 
250     if ((category == AVDTP_SERVICE_CATEGORY_INVALID_0) ||
251         ((category == AVDTP_SERVICE_CATEGORY_INVALID_FF) && (signal_identifier == AVDTP_SI_RECONFIGURE))){
252         log_info("    ERROR: BAD SERVICE CATEGORY %d\n", category);
253         connection->reject_service_category = category;
254         connection->error_code = BAD_SERV_CATEGORY;
255         return 1;
256     }
257 
258     if (signal_identifier == AVDTP_SI_RECONFIGURE){
259         if ( (category != AVDTP_CONTENT_PROTECTION) && (category != AVDTP_MEDIA_CODEC)){
260             log_info("    ERROR: REJECT CATEGORY, INVALID_CAPABILITIES\n");
261             connection->reject_service_category = category;
262             connection->error_code = INVALID_CAPABILITIES;
263             return 1;
264         }
265     }
266 
267     switch(category){
268         case AVDTP_MEDIA_TRANSPORT:
269             if (cap_len != 0){
270                 log_info("    ERROR: REJECT CATEGORY, BAD_MEDIA_TRANSPORT\n");
271                 connection->reject_service_category = category;
272                 connection->error_code = BAD_MEDIA_TRANSPORT_FORMAT;
273                 return 1;
274             }
275             break;
276         case AVDTP_REPORTING:
277         case AVDTP_DELAY_REPORTING:
278             if (cap_len != 0){
279                 log_info("    ERROR: REJECT CATEGORY, BAD_LENGTH\n");
280                 connection->reject_service_category = category;
281                 connection->error_code = BAD_LENGTH;
282                 return 1;
283             }
284             break;
285         case AVDTP_RECOVERY:
286             if (cap_len != 3){
287                 log_info("    ERROR: REJECT CATEGORY, BAD_MEDIA_TRANSPORT\n");
288                 connection->reject_service_category = category;
289                 connection->error_code = BAD_RECOVERY_FORMAT;
290                 return 1;
291             }
292             break;
293         case AVDTP_CONTENT_PROTECTION:
294             if (cap_len < 2){
295                 log_info("    ERROR: REJECT CATEGORY, BAD_CP_FORMAT\n");
296                 connection->reject_service_category = category;
297                 connection->error_code = BAD_CP_FORMAT;
298                 return 1;
299             }
300             break;
301         case AVDTP_HEADER_COMPRESSION:
302             // TODO: find error code for bad header compression
303             if (cap_len != 1){
304                 log_info("    ERROR: REJECT CATEGORY, BAD_HEADER_COMPRESSION\n");
305                 connection->reject_service_category = category;
306                 connection->error_code = BAD_RECOVERY_FORMAT;
307                 return 1;
308             }
309             break;
310         case AVDTP_MULTIPLEXING:
311             break;
312         case AVDTP_MEDIA_CODEC:
313             break;
314         default:
315             break;
316     }
317     return 0;
318 }
319 
320 uint16_t avdtp_unpack_service_capabilities(avdtp_connection_t * connection, avdtp_signal_identifier_t signal_identifier, avdtp_capabilities_t * caps, uint8_t * packet, uint16_t size){
321 
322     int i;
323 
324     uint16_t registered_service_categories = 0;
325     uint16_t to_process = size;
326 
327     while (to_process >= 2){
328 
329         avdtp_service_category_t category = (avdtp_service_category_t) packet[0];
330         uint8_t cap_len = packet[1];
331         packet     += 2;
332         to_process -= 2;
333 
334         if (cap_len > to_process){
335             connection->reject_service_category = category;
336             connection->error_code = BAD_LENGTH;
337             return 0;
338         }
339 
340         if (avdtp_unpack_service_capabilities_has_errors(connection, signal_identifier, category, cap_len)) return 0;
341 
342         int category_valid = 1;
343 
344         uint8_t * data = packet;
345         uint16_t  pos = 0;
346 
347         switch(category){
348             case AVDTP_RECOVERY:
349                 caps->recovery.recovery_type = data[pos++];
350                 caps->recovery.maximum_recovery_window_size = data[pos++];
351                 caps->recovery.maximum_number_media_packets = data[pos++];
352                 break;
353             case AVDTP_CONTENT_PROTECTION:
354                 caps->content_protection.cp_type = big_endian_read_16(data, 0);
355                 caps->content_protection.cp_type_value_len = cap_len - 2;
356                 // connection->reject_service_category = category;
357                 // connection->error_code = UNSUPPORTED_CONFIGURATION;
358                 // support for content protection goes here
359                 break;
360             case AVDTP_HEADER_COMPRESSION:
361                 caps->header_compression.back_ch  = (data[0] >> 7) & 1;
362                 caps->header_compression.media    = (data[0] >> 6) & 1;
363                 caps->header_compression.recovery = (data[0] >> 5) & 1;
364                 break;
365             case AVDTP_MULTIPLEXING:
366                 caps->multiplexing_mode.fragmentation = (data[pos++] >> 7) & 1;
367                 // read [tsid, tcid] for media, reporting. recovery respectively
368                 caps->multiplexing_mode.transport_identifiers_num = 3;
369                 for (i=0; i<caps->multiplexing_mode.transport_identifiers_num; i++){
370                     caps->multiplexing_mode.transport_session_identifiers[i] = (data[pos++] >> 7) & 1;
371                     caps->multiplexing_mode.tcid[i] = (data[pos++] >> 7) & 1;
372                 }
373                 break;
374             case AVDTP_MEDIA_CODEC:
375                 caps->media_codec.media_type = (avdtp_media_type_t)(data[pos++] >> 4);
376                 caps->media_codec.media_codec_type = (avdtp_media_codec_type_t)(data[pos++]);
377                 caps->media_codec.media_codec_information_len = cap_len - 2;
378                 caps->media_codec.media_codec_information = &data[pos++];
379                 break;
380             case AVDTP_MEDIA_TRANSPORT:
381             case AVDTP_REPORTING:
382             case AVDTP_DELAY_REPORTING:
383                 break;
384             default:
385                 category_valid = 0;
386                 break;
387         }
388 
389         if (category_valid) {
390             registered_service_categories = store_bit16(registered_service_categories, category, 1);
391         }
392 
393         packet     += cap_len;
394         to_process -= cap_len;
395     }
396 
397     return registered_service_categories;
398 }
399 
400 void avdtp_prepare_capabilities(avdtp_signaling_packet_t * signaling_packet, uint8_t transaction_label, uint16_t service_categories, avdtp_capabilities_t capabilities, uint8_t identifier){
401     if (signaling_packet->offset) return;
402     bool basic_capabilities_only = false;
403     signaling_packet->message_type = AVDTP_RESPONSE_ACCEPT_MSG;
404     int i;
405 
406     signaling_packet->size = 0;
407     memset(signaling_packet->command, 0 , sizeof(signaling_packet->command));
408 
409     switch (identifier) {
410         case AVDTP_SI_GET_CAPABILITIES:
411             basic_capabilities_only = true;
412             break;
413         case AVDTP_SI_GET_ALL_CAPABILITIES:
414             break;
415         case AVDTP_SI_SET_CONFIGURATION:
416             signaling_packet->command[signaling_packet->size++] = signaling_packet->acp_seid << 2;
417             signaling_packet->command[signaling_packet->size++] = signaling_packet->int_seid << 2;
418             signaling_packet->message_type = AVDTP_CMD_MSG;
419             break;
420         case AVDTP_SI_RECONFIGURE:
421             signaling_packet->command[signaling_packet->size++] = signaling_packet->acp_seid << 2;
422             signaling_packet->message_type = AVDTP_CMD_MSG;
423             break;
424         default:
425             log_error("avdtp_prepare_capabilities wrong identifier %d", identifier);
426             break;
427     }
428 
429     for (i = AVDTP_MEDIA_TRANSPORT; i <= AVDTP_DELAY_REPORTING; i++){
430         int registered_category = get_bit16(service_categories, i);
431         if (!registered_category && (identifier == AVDTP_SI_SET_CONFIGURATION)){
432             // TODO: introduce bitmap of mandatory categories
433             if (i == AVDTP_MEDIA_TRANSPORT){
434                 registered_category = true;
435             }
436         }
437         // AVDTP_SI_GET_CAPABILITIES reports only basic capabilities (i.e., it skips non-basic categories)
438         if (basic_capabilities_only && !avdtp_is_basic_capability(i)){
439             registered_category = false;
440         }
441 
442         if (registered_category){
443             // service category
444             signaling_packet->command[signaling_packet->size++] = i;
445             signaling_packet->size += avdtp_pack_service_capabilities(signaling_packet->command + signaling_packet->size,
446                     sizeof(signaling_packet->command) - signaling_packet->size, capabilities, (avdtp_service_category_t) i);
447         }
448     }
449     signaling_packet->signal_identifier = (avdtp_signal_identifier_t)identifier;
450     signaling_packet->transaction_label = transaction_label;
451 }
452 
453 int avdtp_signaling_create_fragment(uint16_t cid, avdtp_signaling_packet_t * signaling_packet, uint8_t * out_buffer) {
454     int mtu = l2cap_get_remote_mtu_for_local_cid(cid);
455     int data_len = 0;
456 
457     uint16_t offset = signaling_packet->offset;
458     uint16_t pos = 1;
459 
460     if (offset == 0){
461         if (signaling_packet->size <= (mtu - 2)){
462             signaling_packet->packet_type = AVDTP_SINGLE_PACKET;
463             out_buffer[pos++] = signaling_packet->signal_identifier;
464             data_len = signaling_packet->size;
465         } else {
466             signaling_packet->packet_type = AVDTP_START_PACKET;
467             out_buffer[pos++] = (mtu + signaling_packet->size)/ (mtu-1);
468             out_buffer[pos++] = signaling_packet->signal_identifier;
469             data_len = mtu - 3;
470             signaling_packet->offset = data_len;
471         }
472     } else {
473         int remaining_bytes = signaling_packet->size - offset;
474         if (remaining_bytes <= (mtu - 1)){
475             signaling_packet->packet_type = AVDTP_END_PACKET;
476             data_len = remaining_bytes;
477             signaling_packet->offset = 0;
478         } else{
479             signaling_packet->packet_type = AVDTP_CONTINUE_PACKET;
480             data_len = mtu - 1;
481             signaling_packet->offset += data_len;
482         }
483     }
484     out_buffer[0] = avdtp_header(signaling_packet->transaction_label, signaling_packet->packet_type, signaling_packet->message_type);
485     (void)memcpy(out_buffer + pos, signaling_packet->command + offset,
486                  data_len);
487     pos += data_len;
488     return pos;
489 }
490 
491 
492 void avdtp_signaling_emit_connection_established(uint16_t avdtp_cid, bd_addr_t addr, hci_con_handle_t con_handle, uint8_t status) {
493     uint8_t event[14];
494     int pos = 0;
495     event[pos++] = HCI_EVENT_AVDTP_META;
496     event[pos++] = sizeof(event) - 2;
497     event[pos++] = AVDTP_SUBEVENT_SIGNALING_CONNECTION_ESTABLISHED;
498     little_endian_store_16(event, pos, avdtp_cid);
499     pos += 2;
500     reverse_bd_addr(addr,&event[pos]);
501     pos += 6;
502     little_endian_store_16(event, pos, con_handle);
503     pos += 2;
504     event[pos++] = status;
505     avdtp_emit_sink_and_source(event, pos);
506 }
507 
508 void avdtp_signaling_emit_connection_released(uint16_t avdtp_cid) {
509     uint8_t event[5];
510     int pos = 0;
511     event[pos++] = HCI_EVENT_AVDTP_META;
512     event[pos++] = sizeof(event) - 2;
513     event[pos++] = AVDTP_SUBEVENT_SIGNALING_CONNECTION_RELEASED;
514     little_endian_store_16(event, pos, avdtp_cid);
515     pos += 2;
516     avdtp_emit_sink_and_source(event, pos);
517 }
518 
519 void avdtp_signaling_emit_sep(uint16_t avdtp_cid, avdtp_sep_t sep) {
520     uint8_t event[9];
521     int pos = 0;
522     event[pos++] = HCI_EVENT_AVDTP_META;
523     event[pos++] = sizeof(event) - 2;
524     event[pos++] = AVDTP_SUBEVENT_SIGNALING_SEP_FOUND;
525     little_endian_store_16(event, pos, avdtp_cid);
526     pos += 2;
527     event[pos++] = sep.seid;
528     event[pos++] = sep.in_use;
529     event[pos++] = sep.media_type;
530     event[pos++] = sep.type;
531     avdtp_emit_sink_and_source(event, pos);
532 }
533 
534 void avdtp_signaling_emit_sep_done(uint16_t avdtp_cid) {
535     uint8_t event[5];
536     int pos = 0;
537     event[pos++] = HCI_EVENT_AVDTP_META;
538     event[pos++] = sizeof(event) - 2;
539     event[pos++] = AVDTP_SUBEVENT_SIGNALING_SEP_DICOVERY_DONE;
540     little_endian_store_16(event, pos, avdtp_cid);
541     pos += 2;
542     avdtp_emit_sink_and_source(event, pos);
543 }
544 
545 void avdtp_signaling_emit_accept(uint16_t avdtp_cid, uint8_t local_seid, avdtp_signal_identifier_t identifier, bool is_initiator) {
546     uint8_t event[8];
547     int pos = 0;
548     event[pos++] = HCI_EVENT_AVDTP_META;
549     event[pos++] = sizeof(event) - 2;
550     event[pos++] = AVDTP_SUBEVENT_SIGNALING_ACCEPT;
551     little_endian_store_16(event, pos, avdtp_cid);
552     pos += 2;
553     event[pos++] = local_seid;
554     event[pos++] = is_initiator ? 1 : 0;
555     event[pos++] = identifier;
556     avdtp_emit_sink_and_source(event, pos);
557 }
558 
559 void avdtp_signaling_emit_accept_for_stream_endpoint(avdtp_stream_endpoint_t * stream_endpoint, uint8_t local_seid,  avdtp_signal_identifier_t identifier, bool is_initiator){
560     uint8_t event[8];
561     int pos = 0;
562     event[pos++] = HCI_EVENT_AVDTP_META;
563     event[pos++] = sizeof(event) - 2;
564     event[pos++] = AVDTP_SUBEVENT_SIGNALING_ACCEPT;
565     little_endian_store_16(event, pos, stream_endpoint->connection->avdtp_cid);
566     pos += 2;
567     event[pos++] = local_seid;
568     event[pos++] = is_initiator ? 1 : 0;
569     event[pos++] = identifier;
570 
571     btstack_packet_handler_t packet_handler = avdtp_packet_handler_for_stream_endpoint(stream_endpoint);
572     (*packet_handler)(HCI_EVENT_PACKET, 0, event, pos);
573 }
574 
575 void avdtp_signaling_emit_reject(uint16_t avdtp_cid, uint8_t local_seid, avdtp_signal_identifier_t identifier, bool is_initiator) {
576     uint8_t event[8];
577     int pos = 0;
578     event[pos++] = HCI_EVENT_AVDTP_META;
579     event[pos++] = sizeof(event) - 2;
580     event[pos++] = AVDTP_SUBEVENT_SIGNALING_REJECT;
581     little_endian_store_16(event, pos, avdtp_cid);
582     pos += 2;
583     event[pos++] = local_seid;
584     event[pos++] = is_initiator ? 1 : 0;
585     event[pos++] = identifier;
586     avdtp_emit_sink_and_source(event, pos);
587 }
588 
589 void avdtp_signaling_emit_general_reject(uint16_t avdtp_cid, uint8_t local_seid, avdtp_signal_identifier_t identifier, bool is_initiator) {
590     uint8_t event[8];
591     int pos = 0;
592     event[pos++] = HCI_EVENT_AVDTP_META;
593     event[pos++] = sizeof(event) - 2;
594     event[pos++] = AVDTP_SUBEVENT_SIGNALING_GENERAL_REJECT;
595     little_endian_store_16(event, pos, avdtp_cid);
596     pos += 2;
597     event[pos++] = local_seid;
598     event[pos++] = is_initiator ? 1 : 0;
599     event[pos++] = identifier;
600     avdtp_emit_sink_and_source(event, pos);
601 }
602 
603 static inline void
604 avdtp_signaling_emit_capability(uint8_t capability_subevent_id, uint16_t avdtp_cid, uint8_t remote_seid) {
605     uint8_t event[6];
606     int pos = 0;
607     event[pos++] = HCI_EVENT_AVDTP_META;
608     event[pos++] = sizeof(event) - 2;
609     event[pos++] = capability_subevent_id;
610     little_endian_store_16(event, pos, avdtp_cid);
611     pos += 2;
612     event[pos++] = remote_seid;
613     avdtp_emit_sink_and_source(event, pos);
614 }
615 
616 static void avdtp_signaling_emit_media_codec_sbc_capability(uint16_t avdtp_cid, uint8_t remote_seid, adtvp_media_codec_capabilities_t media_codec) {
617     const uint8_t * media_codec_information = media_codec.media_codec_information;
618     uint8_t event[14];
619     int pos = 0;
620     event[pos++] = HCI_EVENT_AVDTP_META;
621     event[pos++] = sizeof(event) - 2;
622     event[pos++] = AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CAPABILITY;
623     little_endian_store_16(event, pos, avdtp_cid);
624     pos += 2;
625     event[pos++] = remote_seid;
626     event[pos++] = media_codec.media_type;
627     event[pos++] = media_codec_information[0] >> 4;
628     event[pos++] = media_codec_information[0] & 0x0F;
629     event[pos++] = media_codec_information[1] >> 4;
630     event[pos++] = (media_codec_information[1] & 0x0F) >> 2;
631     event[pos++] = media_codec_information[1] & 0x03;
632     event[pos++] = media_codec_information[2];
633     event[pos++] = media_codec_information[3];
634     avdtp_emit_sink_and_source(event, pos);
635 }
636 
637 static void avdtp_signaling_emit_media_codec_mpeg_audio_capability(uint16_t avdtp_cid, uint8_t remote_seid, adtvp_media_codec_capabilities_t media_codec) {
638     const uint8_t * media_codec_information = media_codec.media_codec_information;
639     uint8_t event[15];
640     int pos = 0;
641     event[pos++] = HCI_EVENT_AVDTP_META;
642     event[pos++] = sizeof(event) - 2;
643     event[pos++] = AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_MPEG_AUDIO_CAPABILITY;
644     little_endian_store_16(event, pos, avdtp_cid);
645     pos += 2;
646     event[pos++] = remote_seid;
647     event[pos++] = media_codec.media_type;
648 
649     uint8_t layer_bitmap              =   media_codec_information[0] >> 5;
650     uint8_t crc                       =  (media_codec_information[0] >> 4) & 0x01;
651     uint8_t channel_mode_bitmap       =   media_codec_information[0] & 0x07;
652     uint8_t mpf                       =  (media_codec_information[1] >> 6) & 0x01;
653     uint8_t sampling_frequency_bitmap =   media_codec_information[1] & 0x3F;
654     uint8_t vbr                       =  (media_codec_information[2] >> 7) & 0x01;
655     uint16_t bit_rate_index_bitmap    = ((media_codec_information[3] & 0x3f) << 8) | media_codec.media_codec_information[4];
656 
657     event[pos++] = layer_bitmap;
658     event[pos++] = crc;
659     event[pos++] = channel_mode_bitmap;
660     event[pos++] = mpf;
661     event[pos++] = sampling_frequency_bitmap;
662     event[pos++] = vbr;
663     little_endian_store_16(event, pos, bit_rate_index_bitmap);           // bit rate index
664     pos += 2;
665     avdtp_emit_sink_and_source(event, pos);
666 }
667 
668 static void avdtp_signaling_emit_media_codec_mpeg_aac_capability(uint16_t avdtp_cid, uint8_t remote_seid, adtvp_media_codec_capabilities_t media_codec) {
669     const uint8_t * media_codec_information = media_codec.media_codec_information;
670     uint8_t event[15];
671     int pos = 0;
672     event[pos++] = HCI_EVENT_AVDTP_META;
673     event[pos++] = sizeof(event) - 2;
674     event[pos++] = AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_MPEG_AAC_CAPABILITY;
675     little_endian_store_16(event, pos, avdtp_cid);
676     pos += 2;
677     event[pos++] = remote_seid;
678     event[pos++] =  media_codec.media_type;
679 
680     uint8_t  object_type_bitmap        =   media_codec_information[0];
681     uint16_t sampling_frequency_bitmap =  (media_codec_information[1] << 4) | (media_codec_information[2] >> 4);
682     uint8_t  channels_bitmap           =  (media_codec_information[2] >> 2) & 0x03;
683     uint32_t bit_rate_bitmap           = ((media_codec_information[3] & 0x7f) << 16) | (media_codec_information[4] << 8) | media_codec_information[5];
684     uint8_t  vbr                       =   media_codec_information[3] >> 7;
685 
686     event[pos++] =  object_type_bitmap;
687     little_endian_store_16(event, pos, sampling_frequency_bitmap);
688     pos += 2;
689     event[pos++] = channels_bitmap;
690     little_endian_store_24(event, pos, bit_rate_bitmap);
691     pos += 3;
692     event[pos++] = vbr;
693 
694     avdtp_emit_sink_and_source(event, pos);
695 }
696 
697 static void avdtp_signaling_emit_media_codec_atrac_capability(uint16_t avdtp_cid, uint8_t remote_seid, adtvp_media_codec_capabilities_t media_codec) {
698     const uint8_t * media_codec_information = media_codec.media_codec_information;
699     uint8_t event[16];
700     int pos = 0;
701     event[pos++] = HCI_EVENT_AVDTP_META;
702     event[pos++] = sizeof(event) - 2;
703     event[pos++] = AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_ATRAC_CAPABILITY;
704     little_endian_store_16(event, pos, avdtp_cid);
705     pos += 2;
706     event[pos++] = remote_seid;
707     event[pos++] = media_codec.media_type;
708 
709     uint8_t  version                   =  media_codec_information[0] >> 5;
710     uint8_t  channel_mode_bitmap       = (media_codec_information[0] >> 2) & 0x07;
711     uint16_t sampling_frequency_bitmap = (media_codec_information[1] >> 4) & 0x03;
712     uint8_t  vbr                       = (media_codec_information[1] >> 3) & 0x01;
713     uint16_t bit_rate_index_bitmap     = ((media_codec_information[1]) & 0x07) << 16 | (media_codec_information[2] << 8) | media_codec_information[3];
714     uint16_t maximum_sul               = (media_codec_information[4] << 8) | media_codec_information[5];
715 
716     event[pos++] = version;
717     event[pos++] = channel_mode_bitmap;
718     event[pos++] = sampling_frequency_bitmap;
719     event[pos++] = vbr;
720     little_endian_store_24(event, pos, bit_rate_index_bitmap);
721     pos += 3;
722     little_endian_store_16(event, pos, maximum_sul);
723 
724     avdtp_emit_sink_and_source(event, pos);
725 }
726 
727 static void avdtp_signaling_emit_media_codec_other_capability(uint16_t avdtp_cid, uint8_t remote_seid, adtvp_media_codec_capabilities_t media_codec) {
728     uint8_t event[MAX_MEDIA_CODEC_INFORMATION_LENGTH + 11];
729     int pos = 0;
730     event[pos++] = HCI_EVENT_AVDTP_META;
731     event[pos++] = sizeof(event) - 2;
732     event[pos++] = AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_OTHER_CAPABILITY;
733     little_endian_store_16(event, pos, avdtp_cid);
734     pos += 2;
735     event[pos++] = remote_seid;
736     event[pos++] = media_codec.media_type;
737     little_endian_store_16(event, pos, media_codec.media_codec_type);
738     pos += 2;
739     little_endian_store_16(event, pos, media_codec.media_codec_information_len);
740     pos += 2;
741     (void)memcpy(event + pos, media_codec.media_codec_information,
742                  btstack_min(media_codec.media_codec_information_len, MAX_MEDIA_CODEC_INFORMATION_LENGTH));
743     avdtp_emit_sink_and_source(event, pos);
744 }
745 
746 static void
747 avdtp_signaling_emit_media_transport_capability(uint16_t avdtp_cid, uint8_t remote_seid) {
748 	avdtp_signaling_emit_capability(AVDTP_SUBEVENT_SIGNALING_MEDIA_TRANSPORT_CAPABILITY, avdtp_cid,
749 									remote_seid);
750 }
751 
752 static void avdtp_signaling_emit_reporting_capability(uint16_t avdtp_cid, uint8_t remote_seid) {
753 	avdtp_signaling_emit_capability(AVDTP_SUBEVENT_SIGNALING_REPORTING_CAPABILITY, avdtp_cid, remote_seid);
754 }
755 
756 static void
757 avdtp_signaling_emit_delay_reporting_capability(uint16_t avdtp_cid, uint8_t remote_seid) {
758 	avdtp_signaling_emit_capability(AVDTP_SUBEVENT_SIGNALING_DELAY_REPORTING_CAPABILITY, avdtp_cid,
759 									remote_seid);
760 }
761 
762 static void avdtp_signaling_emit_recovery_capability(uint16_t avdtp_cid, uint8_t remote_seid, avdtp_recovery_capabilities_t *recovery) {
763     uint8_t event[9];
764     int pos = 0;
765     event[pos++] = HCI_EVENT_AVDTP_META;
766     event[pos++] = sizeof(event) - 2;
767     event[pos++] = AVDTP_SUBEVENT_SIGNALING_RECOVERY_CAPABILITY;
768     little_endian_store_16(event, pos, avdtp_cid);
769     pos += 2;
770     event[pos++] = remote_seid;
771     event[pos++] = recovery->recovery_type;
772     event[pos++] = recovery->maximum_recovery_window_size;
773     event[pos++] = recovery->maximum_number_media_packets;
774     avdtp_emit_sink_and_source(event, pos);
775 }
776 
777 static void
778 avdtp_signaling_emit_content_protection_capability(uint16_t avdtp_cid, uint8_t remote_seid, adtvp_content_protection_t *content_protection) {
779     uint8_t event[21];
780     int pos = 0;
781     event[pos++] = HCI_EVENT_AVDTP_META;
782     event[pos++] = sizeof(event) - 2;
783     event[pos++] = AVDTP_SUBEVENT_SIGNALING_CONTENT_PROTECTION_CAPABILITY;
784     little_endian_store_16(event, pos, avdtp_cid);
785     pos += 2;
786     event[pos++] = remote_seid;
787 
788     little_endian_store_16(event, pos, content_protection->cp_type);
789     pos += 2;
790     little_endian_store_16(event, pos, content_protection->cp_type_value_len);
791     pos += 2;
792 
793     //TODO: reserve place for value
794     if (content_protection->cp_type_value_len < 10){
795         (void)memcpy(event + pos, content_protection->cp_type_value,
796                      content_protection->cp_type_value_len);
797     }
798     avdtp_emit_sink_and_source(event, pos);
799 }
800 
801 
802 static void
803 avdtp_signaling_emit_header_compression_capability(uint16_t avdtp_cid, uint8_t remote_seid, avdtp_header_compression_capabilities_t *header_compression) {
804     uint8_t event[9];
805     int pos = 0;
806     event[pos++] = HCI_EVENT_AVDTP_META;
807     event[pos++] = sizeof(event) - 2;
808     event[pos++] = AVDTP_SUBEVENT_SIGNALING_HEADER_COMPRESSION_CAPABILITY;
809     little_endian_store_16(event, pos, avdtp_cid);
810     pos += 2;
811     event[pos++] = remote_seid;
812     event[pos++] = header_compression->back_ch;
813     event[pos++] = header_compression->media;
814     event[pos++] = header_compression->recovery;
815     avdtp_emit_sink_and_source(event, pos);
816 }
817 
818 static void
819 avdtp_signaling_emit_content_multiplexing_capability(uint16_t avdtp_cid, uint8_t remote_seid, avdtp_multiplexing_mode_capabilities_t *multiplexing_mode) {
820     uint8_t event[14];
821     int pos = 0;
822     event[pos++] = HCI_EVENT_AVDTP_META;
823     event[pos++] = sizeof(event) - 2;
824     event[pos++] = AVDTP_SUBEVENT_SIGNALING_MULTIPLEXING_CAPABILITY;
825     little_endian_store_16(event, pos, avdtp_cid);
826     pos += 2;
827     event[pos++] = remote_seid;
828 
829     event[pos++] = multiplexing_mode->fragmentation;
830     event[pos++] = multiplexing_mode->transport_identifiers_num;
831 
832     int i;
833     for (i = 0; i < 3; i++){
834         event[pos++] = multiplexing_mode->transport_session_identifiers[i];
835     }
836     for (i = 0; i < 3; i++){
837         event[pos++] = multiplexing_mode->tcid[i];
838     }
839     avdtp_emit_sink_and_source(event, pos);
840 }
841 
842 static void avdtp_signaling_emit_capability_done(uint16_t avdtp_cid, uint8_t remote_seid) {
843     uint8_t event[6];
844     int pos = 0;
845     event[pos++] = HCI_EVENT_AVDTP_META;
846     event[pos++] = sizeof(event) - 2;
847     event[pos++] = AVDTP_SUBEVENT_SIGNALING_CAPABILITIES_DONE;
848     little_endian_store_16(event, pos, avdtp_cid);
849     pos += 2;
850     event[pos++] = remote_seid;
851     avdtp_emit_sink_and_source(event, pos);
852 }
853 
854 // emit events for all capabilities incl. final done event
855 void avdtp_signaling_emit_capabilities(uint16_t avdtp_cid, uint8_t remote_seid, avdtp_capabilities_t *capabilities,
856 									   uint16_t registered_service_categories) {
857     if (get_bit16(registered_service_categories, AVDTP_MEDIA_CODEC)){
858         switch (capabilities->media_codec.media_codec_type){
859             case AVDTP_CODEC_SBC:
860 				avdtp_signaling_emit_media_codec_sbc_capability(avdtp_cid, remote_seid, capabilities->media_codec);
861                 break;
862             case AVDTP_CODEC_MPEG_1_2_AUDIO:
863                 avdtp_signaling_emit_media_codec_mpeg_audio_capability(avdtp_cid, remote_seid, capabilities->media_codec);
864                 break;
865             case AVDTP_CODEC_MPEG_2_4_AAC:
866                 avdtp_signaling_emit_media_codec_mpeg_aac_capability(avdtp_cid, remote_seid, capabilities->media_codec);
867                 break;
868             case AVDTP_CODEC_ATRAC_FAMILY:
869                 avdtp_signaling_emit_media_codec_atrac_capability(avdtp_cid, remote_seid, capabilities->media_codec);
870                 break;
871             default:
872 				avdtp_signaling_emit_media_codec_other_capability(avdtp_cid, remote_seid, capabilities->media_codec);
873                 break;
874         }
875     }
876 
877     if (get_bit16(registered_service_categories, AVDTP_MEDIA_TRANSPORT)){
878 		avdtp_signaling_emit_media_transport_capability(avdtp_cid, remote_seid);
879     }
880     if (get_bit16(registered_service_categories, AVDTP_REPORTING)){
881 		avdtp_signaling_emit_reporting_capability(avdtp_cid, remote_seid);
882     }
883     if (get_bit16(registered_service_categories, AVDTP_RECOVERY)){
884 		avdtp_signaling_emit_recovery_capability(avdtp_cid, remote_seid, &capabilities->recovery);
885     }
886     if (get_bit16(registered_service_categories, AVDTP_CONTENT_PROTECTION)){
887 		avdtp_signaling_emit_content_protection_capability(avdtp_cid, remote_seid,
888 														   &capabilities->content_protection);
889     }
890     if (get_bit16(registered_service_categories, AVDTP_HEADER_COMPRESSION)){
891 		avdtp_signaling_emit_header_compression_capability(avdtp_cid, remote_seid,
892 														   &capabilities->header_compression);
893     }
894     if (get_bit16(registered_service_categories, AVDTP_MULTIPLEXING)){
895 		avdtp_signaling_emit_content_multiplexing_capability(avdtp_cid, remote_seid,
896 															 &capabilities->multiplexing_mode);
897     }
898     if (get_bit16(registered_service_categories, AVDTP_DELAY_REPORTING)){
899 		avdtp_signaling_emit_delay_reporting_capability(avdtp_cid, remote_seid);
900     }
901 	avdtp_signaling_emit_capability_done(avdtp_cid, remote_seid);
902 }
903 
904 static void
905 avdtp_signaling_emit_media_codec_sbc(avdtp_stream_endpoint_t *stream_endpoint, uint16_t avdtp_cid, uint8_t reconfigure,
906                                      avdtp_media_type_t media_type, const uint8_t *media_codec_information) {
907 
908     btstack_packet_handler_t packet_handler = avdtp_packet_handler_for_stream_endpoint(stream_endpoint);
909     uint8_t local_seid = avdtp_local_seid(stream_endpoint);
910     uint8_t remote_seid = avdtp_remote_seid(stream_endpoint);
911 
912     uint8_t event[16 + 2];
913     int pos = 0;
914     event[pos++] = HCI_EVENT_AVDTP_META;
915     event[pos++] = sizeof(event) - 2;
916 
917     event[pos++] = AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CONFIGURATION;
918     little_endian_store_16(event, pos, avdtp_cid);
919     pos += 2;
920     event[pos++] = local_seid;
921     event[pos++] = remote_seid;
922     event[pos++] = reconfigure;
923 
924 
925     uint8_t sampling_frequency_bitmap = media_codec_information[0] >> 4;
926     uint8_t channel_mode_bitmap = media_codec_information[0] & 0x0F;
927     uint8_t block_length_bitmap = media_codec_information[1] >> 4;
928     uint8_t subbands_bitmap = (media_codec_information[1] & 0x0F) >> 2;
929 
930     uint8_t num_channels = 0;
931     avdtp_channel_mode_t channel_mode;
932 
933     if (channel_mode_bitmap & AVDTP_SBC_JOINT_STEREO){
934         channel_mode = AVDTP_CHANNEL_MODE_JOINT_STEREO;
935         num_channels = 2;
936     } else if (channel_mode_bitmap & AVDTP_SBC_STEREO){
937         channel_mode = AVDTP_CHANNEL_MODE_STEREO;
938         num_channels = 2;
939     } else if (channel_mode_bitmap & AVDTP_SBC_DUAL_CHANNEL){
940         channel_mode = AVDTP_CHANNEL_MODE_DUAL_CHANNEL;
941         num_channels = 2;
942     } else {
943         channel_mode = AVDTP_CHANNEL_MODE_MONO;
944         num_channels = 1;
945     }
946 
947     uint16_t sampling_frequency = 0;
948     if (sampling_frequency_bitmap & AVDTP_SBC_48000) {
949         sampling_frequency = 48000;
950     } else if (sampling_frequency_bitmap & AVDTP_SBC_44100) {
951         sampling_frequency = 44100;
952     } else if (sampling_frequency_bitmap & AVDTP_SBC_32000) {
953         sampling_frequency = 32000;
954     } else if (sampling_frequency_bitmap & AVDTP_SBC_16000) {
955         sampling_frequency = 16000;
956     }
957 
958     uint8_t subbands = 0;
959     if (subbands_bitmap & AVDTP_SBC_SUBBANDS_8){
960         subbands = 8;
961     } else if (subbands_bitmap & AVDTP_SBC_SUBBANDS_4){
962         subbands = 4;
963     }
964 
965     uint8_t block_length = 0;
966     if (block_length_bitmap & AVDTP_SBC_BLOCK_LENGTH_16){
967         block_length = 16;
968     } else if (block_length_bitmap & AVDTP_SBC_BLOCK_LENGTH_12){
969         block_length = 12;
970     } else if (block_length_bitmap & AVDTP_SBC_BLOCK_LENGTH_8){
971         block_length = 8;
972     } else if (block_length_bitmap & AVDTP_SBC_BLOCK_LENGTH_4){
973         block_length = 4;
974     }
975 
976     event[pos++] = media_type;
977     little_endian_store_16(event, pos, sampling_frequency);
978     pos += 2;
979 
980     event[pos++] = (uint8_t) channel_mode;
981     event[pos++] = num_channels;
982     event[pos++] = block_length;
983     event[pos++] = subbands;
984     event[pos++] = media_codec_information[1] & 0x03;
985     event[pos++] = media_codec_information[2];
986     event[pos++] = media_codec_information[3];
987     (*packet_handler)(HCI_EVENT_PACKET, 0, event, pos);
988 }
989 
990 static void
991 avdtp_signaling_emit_media_codec_mpeg_audio_configuration(avdtp_stream_endpoint_t *stream_endpoint, uint16_t avdtp_cid,
992                                                           uint8_t reconfigure, avdtp_media_type_t media_type,
993                                                           const uint8_t *media_codec_information) {
994 
995     btstack_packet_handler_t packet_handler = avdtp_packet_handler_for_stream_endpoint(stream_endpoint);
996     uint8_t local_seid = avdtp_local_seid(stream_endpoint);
997     uint8_t remote_seid = avdtp_remote_seid(stream_endpoint);
998 
999     uint8_t event[18];
1000     int pos = 0;
1001     event[pos++] = HCI_EVENT_AVDTP_META;
1002     event[pos++] = sizeof(event) - 2;
1003 
1004     event[pos++] = AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_MPEG_AUDIO_CONFIGURATION;
1005     little_endian_store_16(event, pos, avdtp_cid);
1006     pos += 2;
1007     event[pos++] = local_seid;
1008     event[pos++] = remote_seid;
1009     event[pos++] = reconfigure;
1010 
1011     uint8_t layer_bitmap              =   media_codec_information[0] >> 5;
1012     uint8_t crc                       =  (media_codec_information[0] >> 4) & 0x01;
1013     uint8_t channel_mode_bitmap       =  (media_codec_information[0] & 0x07);
1014     uint8_t mpf                       =  (media_codec_information[1] >> 6) & 0x01;
1015     uint8_t sampling_frequency_bitmap =  (media_codec_information[1] & 0x3F);
1016     uint8_t vbr                       =  (media_codec_information[2] >> 7) & 0x01;
1017     uint16_t bit_rate_index_bitmap    = ((media_codec_information[2] & 0x3f) << 8) | media_codec_information[3];
1018 
1019     uint8_t layer = 0;
1020     if (layer_bitmap & 0x04){
1021         layer = AVDTP_MPEG_LAYER_1;
1022     } else if (layer_bitmap & 0x02){
1023         layer = AVDTP_MPEG_LAYER_2;
1024     } else if (layer_bitmap & 0x01){
1025         layer = AVDTP_MPEG_LAYER_3;
1026     }
1027 
1028     uint8_t num_channels = 0;
1029     avdtp_channel_mode_t channel_mode = AVDTP_CHANNEL_MODE_JOINT_STEREO;
1030     if (channel_mode_bitmap & 0x08){
1031         num_channels = 1;
1032         channel_mode = AVDTP_CHANNEL_MODE_MONO;
1033     } else if (channel_mode_bitmap & 0x04){
1034         num_channels = 2;
1035         channel_mode = AVDTP_CHANNEL_MODE_DUAL_CHANNEL;
1036     } else if (channel_mode_bitmap & 0x02){
1037         num_channels = 2;
1038         channel_mode = AVDTP_CHANNEL_MODE_STEREO;
1039     } else if (channel_mode_bitmap & 0x02){
1040         num_channels = 2;
1041         channel_mode = AVDTP_CHANNEL_MODE_JOINT_STEREO;
1042     }
1043 
1044     uint16_t sampling_frequency = 0;
1045     if (sampling_frequency_bitmap & 0x01) {
1046         sampling_frequency = 48000;
1047     } else if (sampling_frequency_bitmap & 0x02) {
1048         sampling_frequency = 44100;
1049     } else if (sampling_frequency_bitmap & 0x04) {
1050         sampling_frequency = 32000;
1051     } else if (sampling_frequency_bitmap & 0x08) {
1052         sampling_frequency = 24000;
1053     } else if (sampling_frequency_bitmap & 0x10) {
1054         sampling_frequency = 22050;
1055     } else if (sampling_frequency_bitmap & 0x20) {
1056         sampling_frequency = 16000;
1057     }
1058 
1059     uint8_t bitrate_index = 0;
1060     uint8_t i;
1061     for (i=0;i<14;i++){
1062         if (bit_rate_index_bitmap & (1U << i)) {
1063             bitrate_index = i;
1064         }
1065     }
1066 
1067     event[pos++] = media_type;
1068     event[pos++] = (uint8_t) layer;
1069     event[pos++] = crc;
1070     event[pos++] = (uint8_t) channel_mode;
1071     event[pos++] = num_channels;
1072     event[pos++] = mpf;
1073     little_endian_store_16(event, pos, sampling_frequency);
1074     pos += 2;
1075     event[pos++] = vbr;
1076     event[pos++] = bitrate_index;
1077 
1078     (*packet_handler)(HCI_EVENT_PACKET, 0, event, pos);
1079 }
1080 
1081 
1082 static void
1083 avdtp_signaling_emit_media_codec_mpeg_aac_configuration(avdtp_stream_endpoint_t *stream_endpoint, uint16_t avdtp_cid,
1084                                                         uint8_t reconfigure, avdtp_media_type_t media_type,
1085                                                         const uint8_t *media_codec_information) {
1086 
1087     btstack_packet_handler_t packet_handler = avdtp_packet_handler_for_stream_endpoint(stream_endpoint);
1088     uint8_t local_seid = avdtp_local_seid(stream_endpoint);
1089     uint8_t remote_seid = avdtp_remote_seid(stream_endpoint);
1090 
1091     uint8_t event[18];
1092     int pos = 0;
1093     event[pos++] = HCI_EVENT_AVDTP_META;
1094     event[pos++] = sizeof(event) - 2;
1095 
1096     event[pos++] = AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_MPEG_AAC_CONFIGURATION;
1097     little_endian_store_16(event, pos, avdtp_cid);
1098     pos += 2;
1099     event[pos++] = local_seid;
1100     event[pos++] = remote_seid;
1101     event[pos++] = reconfigure;
1102 
1103     uint8_t  object_type_bitmap        =   media_codec_information[0];
1104     uint16_t sampling_frequency_bitmap =  (media_codec_information[1] << 4) | (media_codec_information[2] >> 4);
1105     uint8_t  channels_bitmap           =  (media_codec_information[2] >> 2) & 0x03;
1106     uint8_t  vbr                       =   media_codec_information[3] >> 7;
1107     uint32_t bit_rate                  = ((media_codec_information[3] & 0x7f) << 16) | (media_codec_information[4] << 8) | media_codec_information[5];
1108 
1109     uint8_t object_type = 0;
1110     if (object_type_bitmap & 0x80){
1111         object_type = AVDTP_AAC_MPEG2_LC;
1112     } else if (object_type_bitmap & 0x40){
1113         object_type = AVDTP_AAC_MPEG4_LC;
1114     } else if (object_type_bitmap & 0x020){
1115         object_type = AVDTP_AAC_MPEG4_LTP;
1116     } else if (object_type_bitmap & 0x010){
1117         object_type = AVDTP_AAC_MPEG4_SCALABLE;
1118     }
1119 
1120     uint32_t sampling_frequency = 0;
1121     uint8_t i;
1122     const uint32_t aac_sampling_frequency_table[] = {
1123         96000, 88200, 64000, 48000, 44100, 32000, 24000, 22050, 16000, 12000, 11025, 8000
1124     };
1125     for (i=0;i<12;i++){
1126         if (sampling_frequency_bitmap & (1U << i)) {
1127             sampling_frequency = aac_sampling_frequency_table[i];
1128         }
1129     }
1130 
1131     uint8_t num_channels = 0;
1132     if (channels_bitmap & 0x02){
1133         num_channels = 1;
1134     } else if (channels_bitmap & 0x01){
1135         num_channels = 2;
1136     }
1137 
1138     event[pos++] = media_type;
1139     event[pos++] = object_type;
1140     little_endian_store_24(event, pos, sampling_frequency);
1141     pos += 3;
1142     event[pos++] = num_channels;
1143     little_endian_store_24(event, pos, bit_rate);
1144     pos += 3;
1145     event[pos++] = vbr;
1146 
1147     (*packet_handler)(HCI_EVENT_PACKET, 0, event, pos);
1148 }
1149 
1150 static void
1151 avdtp_signaling_emit_media_codec_atrac_configuration(avdtp_stream_endpoint_t *stream_endpoint, uint16_t avdtp_cid,
1152                                                      uint8_t reconfigure, avdtp_media_type_t media_type,
1153                                                      const uint8_t *media_codec_information) {
1154 
1155     btstack_packet_handler_t packet_handler = avdtp_packet_handler_for_stream_endpoint(stream_endpoint);
1156     uint8_t local_seid = avdtp_local_seid(stream_endpoint);
1157     uint8_t remote_seid = avdtp_remote_seid(stream_endpoint);
1158 
1159     uint8_t event[18];
1160     int pos = 0;
1161     event[pos++] = HCI_EVENT_AVDTP_META;
1162     event[pos++] = sizeof(event) - 2;
1163 
1164     event[pos++] = AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_ATRAC_CONFIGURATION;
1165     little_endian_store_16(event, pos, avdtp_cid);
1166     pos += 2;
1167     event[pos++] = local_seid;
1168     event[pos++] = remote_seid;
1169     event[pos++] = reconfigure;
1170 
1171     avdtp_atrac_version_t  version     = (avdtp_atrac_version_t) (media_codec_information[0] >> 5);
1172     uint8_t  channel_mode_bitmap       = (media_codec_information[0] >> 2) & 0x07;
1173     uint16_t sampling_frequency_bitmap = (media_codec_information[1] >> 4) & 0x03;
1174     uint8_t  vbr                       = (media_codec_information[1] >> 3) & 0x01;
1175     uint16_t bit_rate_index_bitmap     = ((media_codec_information[1]) & 0x07) << 16 | (media_codec_information[2] << 8) | media_codec_information[3];
1176     uint16_t maximum_sul               = (media_codec_information[4] << 8) | media_codec_information[5];
1177 
1178     uint8_t num_channels = 0;
1179     avdtp_channel_mode_t channel_mode = AVDTP_CHANNEL_MODE_JOINT_STEREO;
1180     if (channel_mode_bitmap & 0x04){
1181         num_channels = 1;
1182         channel_mode = AVDTP_CHANNEL_MODE_MONO;
1183     } else if (channel_mode_bitmap & 0x02){
1184         num_channels = 2;
1185         channel_mode = AVDTP_CHANNEL_MODE_DUAL_CHANNEL;
1186     } else if (channel_mode_bitmap & 0x01){
1187         num_channels = 2;
1188         channel_mode = AVDTP_CHANNEL_MODE_JOINT_STEREO;
1189     }
1190 
1191     uint16_t sampling_frequency = 0;
1192     if (sampling_frequency_bitmap & 0x02){
1193         sampling_frequency = 44100;
1194     } else if (sampling_frequency_bitmap & 0x01){
1195         sampling_frequency = 48000;
1196     }
1197 
1198     // bit 0 = index 0x18, bit 19 = index 0
1199     uint8_t bit_rate_index = 0;
1200     uint8_t i;
1201     for (i=0;i <= 19;i++){
1202         if (bit_rate_index_bitmap & (1U << i)) {
1203             bit_rate_index = 18 - i;
1204         }
1205     }
1206 
1207     event[pos++] = media_type;
1208     event[pos++] = (uint8_t) version;
1209     event[pos++] = (uint8_t) channel_mode;
1210     event[pos++] = num_channels;
1211     little_endian_store_16(event, pos, sampling_frequency);
1212     pos += 2;
1213     event[pos++] = vbr;
1214     event[pos++] = bit_rate_index;
1215     little_endian_store_16(event, pos, maximum_sul);
1216     pos += 2;
1217 
1218     (*packet_handler)(HCI_EVENT_PACKET, 0, event, pos);
1219 }
1220 
1221 static void avdtp_signaling_emit_media_codec_other_configuration(avdtp_stream_endpoint_t *stream_endpoint, uint16_t avdtp_cid,
1222                                                    uint8_t reconfigure, adtvp_media_codec_capabilities_t *media_codec) {
1223 
1224     btstack_packet_handler_t packet_handler = avdtp_packet_handler_for_stream_endpoint(stream_endpoint);
1225     uint8_t local_seid = avdtp_local_seid(stream_endpoint);
1226     uint8_t remote_seid = avdtp_remote_seid(stream_endpoint);
1227 
1228     uint8_t event[MAX_MEDIA_CODEC_INFORMATION_LENGTH + 13];
1229     int pos = 0;
1230     event[pos++] = HCI_EVENT_AVDTP_META;
1231     event[pos++] = sizeof(event) - 2;
1232     event[pos++] = AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_OTHER_CONFIGURATION;
1233     little_endian_store_16(event, pos, avdtp_cid);
1234     pos += 2;
1235     event[pos++] = local_seid;
1236     event[pos++] = remote_seid;
1237     event[pos++] = reconfigure;
1238     event[pos++] = media_codec->media_type;
1239     little_endian_store_16(event, pos, media_codec->media_codec_type);
1240     pos += 2;
1241     little_endian_store_16(event, pos, media_codec->media_codec_information_len);
1242     pos += 2;
1243 
1244     int media_codec_len = btstack_min(MAX_MEDIA_CODEC_INFORMATION_LENGTH, media_codec->media_codec_information_len);
1245     (void)memcpy(event + pos, media_codec->media_codec_information, media_codec_len);
1246 
1247     (*packet_handler)(HCI_EVENT_PACKET, 0, event, sizeof(event));
1248 }
1249 
1250 void avdtp_signaling_emit_delay(uint16_t avdtp_cid, uint8_t local_seid, uint16_t delay) {
1251     uint8_t event[8];
1252     int pos = 0;
1253     event[pos++] = HCI_EVENT_AVDTP_META;
1254     event[pos++] = sizeof(event) - 2;
1255     event[pos++] = AVDTP_SUBEVENT_SIGNALING_DELAY_REPORT;
1256     little_endian_store_16(event, pos, avdtp_cid);
1257     pos += 2;
1258     event[pos++] = local_seid;
1259     little_endian_store_16(event, pos, delay);
1260     pos += 2;
1261     avdtp_emit_source(event, sizeof(event));
1262 }
1263 
1264 void avdtp_signaling_emit_configuration(avdtp_stream_endpoint_t *stream_endpoint, uint16_t avdtp_cid, uint8_t reconfigure,
1265                                    avdtp_capabilities_t *configuration, uint16_t configured_service_categories) {
1266 
1267     if (get_bit16(configured_service_categories, AVDTP_MEDIA_CODEC)){
1268         switch (configuration->media_codec.media_codec_type){
1269             case AVDTP_CODEC_SBC: {
1270                 avdtp_signaling_emit_media_codec_sbc(stream_endpoint, avdtp_cid, reconfigure,
1271                                                      configuration->media_codec.media_type,
1272                                                      configuration->media_codec.media_codec_information);
1273             }
1274                 break;
1275             case AVDTP_CODEC_MPEG_1_2_AUDIO:
1276                 avdtp_signaling_emit_media_codec_mpeg_audio_configuration(
1277                         stream_endpoint, avdtp_cid, reconfigure,
1278                         configuration->media_codec.media_type,
1279                         configuration->media_codec.media_codec_information);
1280                 break;
1281             case AVDTP_CODEC_MPEG_2_4_AAC:
1282                 avdtp_signaling_emit_media_codec_mpeg_aac_configuration(
1283                         stream_endpoint, avdtp_cid, reconfigure,
1284                         configuration->media_codec.media_type,
1285                         configuration->media_codec.media_codec_information);
1286                 break;
1287             case AVDTP_CODEC_ATRAC_FAMILY:
1288                 avdtp_signaling_emit_media_codec_atrac_configuration(
1289                         stream_endpoint, avdtp_cid, reconfigure,
1290                         configuration->media_codec.media_type,
1291                         configuration->media_codec.media_codec_information);
1292                 break;
1293             default:
1294                 avdtp_signaling_emit_media_codec_other_configuration(stream_endpoint, avdtp_cid, reconfigure, &configuration->media_codec);
1295                 break;
1296         }
1297     }
1298 }
1299 
1300 void avdtp_streaming_emit_connection_established(avdtp_stream_endpoint_t *stream_endpoint, uint8_t status) {
1301     uint8_t event[14];
1302     int pos = 0;
1303     event[pos++] = HCI_EVENT_AVDTP_META;
1304     event[pos++] = sizeof(event) - 2;
1305     event[pos++] = AVDTP_SUBEVENT_STREAMING_CONNECTION_ESTABLISHED;
1306     little_endian_store_16(event, pos, stream_endpoint->connection->avdtp_cid);
1307     pos += 2;
1308     reverse_bd_addr(stream_endpoint->connection->remote_addr, &event[pos]);
1309     pos += 6;
1310     event[pos++] = avdtp_local_seid(stream_endpoint);
1311     event[pos++] = avdtp_remote_seid(stream_endpoint);
1312     event[pos++] = status;
1313 
1314     btstack_packet_handler_t packet_handler = avdtp_packet_handler_for_stream_endpoint(stream_endpoint);
1315     (*packet_handler)(HCI_EVENT_PACKET, 0, event, sizeof(event));
1316 }
1317 
1318 void avdtp_streaming_emit_connection_released(avdtp_stream_endpoint_t *stream_endpoint, uint16_t avdtp_cid, uint8_t local_seid) {
1319     uint8_t event[6];
1320     int pos = 0;
1321     event[pos++] = HCI_EVENT_AVDTP_META;
1322     event[pos++] = sizeof(event) - 2;
1323     event[pos++] = AVDTP_SUBEVENT_STREAMING_CONNECTION_RELEASED;
1324     little_endian_store_16(event, pos, avdtp_cid);
1325     pos += 2;
1326     event[pos++] = local_seid;
1327 
1328     btstack_packet_handler_t packet_handler = avdtp_packet_handler_for_stream_endpoint(stream_endpoint);
1329     (*packet_handler)(HCI_EVENT_PACKET, 0, event, sizeof(event));
1330 }
1331 
1332 void avdtp_streaming_emit_can_send_media_packet_now(avdtp_stream_endpoint_t *stream_endpoint, uint16_t sequence_number) {
1333     uint8_t event[8];
1334     int pos = 0;
1335     event[pos++] = HCI_EVENT_AVDTP_META;
1336     event[pos++] = sizeof(event) - 2;
1337     event[pos++] = AVDTP_SUBEVENT_STREAMING_CAN_SEND_MEDIA_PACKET_NOW;
1338     little_endian_store_16(event, pos, stream_endpoint->connection->avdtp_cid);
1339     pos += 2;
1340     event[pos++] = avdtp_local_seid(stream_endpoint);
1341     little_endian_store_16(event, pos, sequence_number);
1342     pos += 2;
1343 
1344     btstack_packet_handler_t packet_handler = avdtp_packet_handler_for_stream_endpoint(stream_endpoint);
1345     (*packet_handler)(HCI_EVENT_PACKET, 0, event, sizeof(event));
1346 }
1347 
1348 uint8_t avdtp_request_can_send_now_acceptor(avdtp_connection_t *connection) {
1349     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
1350     connection->wait_to_send_acceptor = true;
1351     l2cap_request_can_send_now_event(connection->l2cap_signaling_cid);
1352     return ERROR_CODE_SUCCESS;
1353 }
1354 
1355 uint8_t avdtp_request_can_send_now_initiator(avdtp_connection_t *connection) {
1356     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
1357     connection->wait_to_send_initiator = true;
1358     l2cap_request_can_send_now_event(connection->l2cap_signaling_cid);
1359     return ERROR_CODE_SUCCESS;
1360 }
1361 
1362 uint8_t avdtp_local_seid(avdtp_stream_endpoint_t * stream_endpoint){
1363     if (!stream_endpoint) return 0;
1364     return stream_endpoint->sep.seid;
1365 
1366 }
1367 
1368 uint8_t avdtp_remote_seid(avdtp_stream_endpoint_t * stream_endpoint){
1369     if (!stream_endpoint) return AVDTP_INVALID_SEP_SEID;
1370     return stream_endpoint->remote_sep.seid;
1371 }
1372 
1373 // helper for A2DP
1374 
1375 void a2dp_replace_subevent_id_and_emit_cmd(btstack_packet_handler_t callback, uint8_t * packet, uint16_t size, uint8_t subevent_id){
1376     UNUSED(size);
1377     btstack_assert(callback != NULL);
1378     // cache orig event and subevent id
1379     uint8_t orig_event_id    = packet[0];
1380     uint8_t orig_subevent_id = packet[2];
1381     // execute callback
1382     packet[0] = HCI_EVENT_A2DP_META;
1383     packet[2] = subevent_id;
1384     (*callback)(HCI_EVENT_PACKET, 0, packet, size);
1385     // restore id
1386     packet[0] = orig_event_id;
1387     packet[2] = orig_subevent_id;
1388 }
1389 
1390 void a2dp_emit_stream_event(btstack_packet_handler_t callback, uint16_t cid, uint8_t local_seid, uint8_t subevent_id){
1391     uint8_t event[6];
1392     int pos = 0;
1393     event[pos++] = HCI_EVENT_A2DP_META;
1394     event[pos++] = sizeof(event) - 2;
1395     event[pos++] = subevent_id;
1396     little_endian_store_16(event, pos, cid);
1397     pos += 2;
1398     event[pos++] = local_seid;
1399     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
1400 }
1401 
1402 // helper to set/get configuration
1403 void avdtp_config_sbc_set_sampling_frequency(uint8_t * config, uint16_t sampling_frequency_hz){
1404     avdtp_sbc_sampling_frequency_t sampling_frequency;
1405     switch (sampling_frequency_hz){
1406         case 16000:
1407             sampling_frequency = AVDTP_SBC_16000;
1408             break;
1409         case 32000:
1410             sampling_frequency = AVDTP_SBC_32000;
1411             break;
1412         case 48000:
1413             sampling_frequency = AVDTP_SBC_48000;
1414             break;
1415         default:
1416             sampling_frequency = AVDTP_SBC_44100;
1417             break;
1418     }
1419     config[0] = (((uint8_t) sampling_frequency) << 4) | (config[0] & 0x0f);
1420 }
1421 
1422 void avdtp_config_sbc_store(uint8_t * config, uint16_t sampling_frequency_hz, avdtp_channel_mode_t channel_mode, uint8_t block_length, uint8_t subbands,
1423                                    avdtp_sbc_allocation_method_t  allocation_method, uint8_t min_bitpool_value, uint8_t max_bitpool_value) {
1424     avdtp_sbc_channel_mode_t sbc_channel_mode;
1425     switch (channel_mode){
1426         case AVDTP_CHANNEL_MODE_MONO:
1427             sbc_channel_mode = AVDTP_SBC_MONO;
1428             break;
1429         case AVDTP_CHANNEL_MODE_DUAL_CHANNEL:
1430             sbc_channel_mode = AVDTP_SBC_DUAL_CHANNEL;
1431             break;
1432         case AVDTP_CHANNEL_MODE_STEREO:
1433             sbc_channel_mode = AVDTP_SBC_STEREO;
1434             break;
1435         default:
1436             sbc_channel_mode = AVDTP_SBC_JOINT_STEREO;
1437             break;
1438     }
1439     config[0] = (uint8_t) sbc_channel_mode;
1440     config[1] = (block_length << 4) | (subbands << 2) | allocation_method;
1441     config[2] = min_bitpool_value;
1442     config[3] = max_bitpool_value;
1443     avdtp_config_sbc_set_sampling_frequency(config, sampling_frequency_hz);
1444 }
1445 
1446 void avdtp_config_mpeg_audio_set_sampling_frequency(uint8_t * config, uint16_t sampling_frequency_hz) {
1447     uint8_t sampling_frequency_index = 0;
1448     switch (sampling_frequency_hz){
1449         case 16000:
1450             sampling_frequency_index = 5;
1451             break;
1452         case 22040:
1453             sampling_frequency_index = 4;
1454             break;
1455         case 24000:
1456             sampling_frequency_index = 3;
1457             break;
1458         case 32000:
1459             sampling_frequency_index = 2;
1460             break;
1461         case 44100:
1462             sampling_frequency_index = 1;
1463             break;
1464         case 48000:
1465             sampling_frequency_index = 0;
1466             break;
1467     }
1468     config[1] = (config[1] & 0xC0) | (1 << sampling_frequency_index);
1469 }
1470 
1471 void avdtp_config_mpeg_audio_store(uint8_t * config, avdtp_mpeg_layer_t layer, uint8_t crc, avdtp_channel_mode_t channel_mode, uint8_t media_payload_format,
1472                                           uint16_t sampling_frequency, uint8_t vbr, uint8_t bit_rate_index){
1473 
1474     config[0] = (1 << (7 - (layer - AVDTP_MPEG_LAYER_1))) | ((crc & 0x01) << 4) | (1 << (channel_mode - AVDTP_CHANNEL_MODE_MONO));
1475     config[1] = ((media_payload_format & 0x01) << 6) ;
1476     uint16_t bit_rate_mask = 1 << bit_rate_index;
1477     config[2] = ((vbr & 0x01) << 7) | ((bit_rate_mask >> 8) & 0x3f);
1478     config[3] = bit_rate_mask & 0xff;
1479     avdtp_config_mpeg_audio_set_sampling_frequency(config, sampling_frequency);
1480 }
1481 
1482 
1483 void avdtp_config_mpeg_aac_set_sampling_frequency(uint8_t * config, uint16_t sampling_frequency_hz) {
1484     uint16_t sampling_frequency_bitmap = 0;
1485     uint8_t i;
1486     const uint32_t aac_sampling_frequency_table[] = {
1487             96000, 88200, 64000, 48000, 44100, 32000, 24000, 22050, 16000, 12000, 11025, 8000
1488     };
1489     for (i=0;i<12;i++){
1490         if (sampling_frequency_hz == aac_sampling_frequency_table[i]){
1491             sampling_frequency_bitmap = 1 << i;
1492             break;
1493         }
1494     }
1495     config[1] = sampling_frequency_bitmap >> 4;
1496     config[2] = ((sampling_frequency_bitmap & 0x0f) << 4) | (config[2] & 0x0f);
1497 }
1498 
1499 void avdtp_config_mpeg_aac_store(uint8_t * config,  avdtp_aac_object_type_t object_type, uint32_t sampling_frequency, uint8_t channels, uint32_t bit_rate, uint8_t vbr) {
1500     config[0] = 1 << (7 -(object_type - AVDTP_AAC_MPEG2_LC));
1501     uint8_t channels_bitmap = 0;
1502     switch (channels){
1503         case 1:
1504             channels_bitmap = 0x02;
1505             break;
1506         case 2:
1507             channels_bitmap = 0x01;
1508             break;
1509         default:
1510             break;
1511     }
1512     config[2] = channels_bitmap << 2;
1513     config[3] = ((vbr & 0x01) << 7) | ((bit_rate >> 16) & 0x7f);
1514     config[4] = (bit_rate >> 8) & 0xff;
1515     config[5] =  bit_rate & 0xff;
1516     avdtp_config_mpeg_aac_set_sampling_frequency(config, sampling_frequency);
1517 }
1518 
1519 void avdtp_config_atrac_set_sampling_frequency(uint8_t * config, uint16_t sampling_frequency_hz) {
1520     uint8_t fs_bitmap = 0;
1521     switch (sampling_frequency_hz){
1522         case 44100:
1523             fs_bitmap = 2;
1524             break;
1525         case 48000:
1526             fs_bitmap = 1;
1527             break;
1528         default:
1529             break;
1530     }
1531     config[1] = (fs_bitmap << 4) | (config[1] & 0x0F);
1532 }
1533 
1534 void avdtp_config_atrac_store(uint8_t * config, avdtp_atrac_version_t version, avdtp_channel_mode_t channel_mode, uint16_t sampling_frequency, uint8_t vbr,
1535                                      uint8_t bit_rate_index, uint16_t maximum_sul) {
1536     uint8_t channel_mode_bitmap = 0;
1537     switch (channel_mode){
1538         case AVDTP_CHANNEL_MODE_MONO:
1539             channel_mode_bitmap = 4;
1540             break;
1541         case AVDTP_CHANNEL_MODE_DUAL_CHANNEL:
1542             channel_mode_bitmap = 2;
1543             break;
1544         case AVDTP_CHANNEL_MODE_JOINT_STEREO:
1545             channel_mode_bitmap = 1;
1546             break;
1547         default:
1548             break;
1549     }
1550     config[0] = ((version - AVDTP_ATRAC_VERSION_1 + 1) << 5) | (channel_mode_bitmap << 2);
1551     uint32_t bit_rate_bitmap = 1 << (0x18 - bit_rate_index);
1552     config[1] = ((vbr & 0x01) << 3) | ((bit_rate_bitmap >> 16) & 0x07);
1553     config[2] = (bit_rate_bitmap >> 8) & 0xff;
1554     config[3] = bit_rate_bitmap & 0xff;
1555     config[4] = maximum_sul >> 8;
1556     config[5] = maximum_sul & 0xff;
1557     config[6] = 0;
1558     avdtp_config_atrac_set_sampling_frequency(config, sampling_frequency);
1559 }
1560