xref: /btstack/src/classic/avrcp_controller.c (revision 6973c35a87cc7f398c429d8942b18d0a401e28a3)
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__ "avrcp_controller.c"
39 
40 #include <stdint.h>
41 #include <stdio.h>
42 #include <stdlib.h>
43 #include <string.h>
44 #include <inttypes.h>
45 
46 #include "btstack.h"
47 #include "classic/avrcp.h"
48 #include "classic/avrcp_controller.h"
49 
50 // made public in avrcp_controller.h
51 avrcp_context_t avrcp_controller_context;
52 
53 void avrcp_controller_create_sdp_record(uint8_t * service, uint32_t service_record_handle, uint8_t browsing, uint16_t supported_features, const char * service_name, const char * service_provider_name){
54     avrcp_create_sdp_record(1, service, service_record_handle, browsing, supported_features, service_name, service_provider_name);
55 }
56 
57 static void avrcp_emit_repeat_and_shuffle_mode(btstack_packet_handler_t callback, uint16_t avrcp_cid, uint8_t ctype, avrcp_repeat_mode_t repeat_mode, avrcp_shuffle_mode_t shuffle_mode){
58     if (!callback) return;
59     uint8_t event[8];
60     int pos = 0;
61     event[pos++] = HCI_EVENT_AVRCP_META;
62     event[pos++] = sizeof(event) - 2;
63     event[pos++] = AVRCP_SUBEVENT_SHUFFLE_AND_REPEAT_MODE;
64     little_endian_store_16(event, pos, avrcp_cid);
65     pos += 2;
66     event[pos++] = ctype;
67     event[pos++] = repeat_mode;
68     event[pos++] = shuffle_mode;
69     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
70 }
71 
72 static void avrcp_emit_operation_status(btstack_packet_handler_t callback, uint8_t subevent, uint16_t avrcp_cid, uint8_t ctype, uint8_t operation_id){
73     if (!callback) return;
74     uint8_t event[7];
75     int pos = 0;
76     event[pos++] = HCI_EVENT_AVRCP_META;
77     event[pos++] = sizeof(event) - 2;
78     event[pos++] = subevent;
79     little_endian_store_16(event, pos, avrcp_cid);
80     pos += 2;
81     event[pos++] = ctype;
82     event[pos++] = operation_id;
83     (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
84 }
85 
86 static void avrcp_press_and_hold_timeout_handler(btstack_timer_source_t * timer){
87     UNUSED(timer);
88     avrcp_connection_t * connection = btstack_run_loop_get_timer_context(timer);
89     btstack_run_loop_set_timer(&connection->press_and_hold_cmd_timer, 2000); // 2 seconds timeout
90     btstack_run_loop_add_timer(&connection->press_and_hold_cmd_timer);
91     connection->state = AVCTP_W2_SEND_PRESS_COMMAND;
92     avrcp_request_can_send_now(connection, connection->l2cap_signaling_cid);
93 }
94 
95 static void avrcp_press_and_hold_timer_start(avrcp_connection_t * connection){
96     btstack_run_loop_remove_timer(&connection->press_and_hold_cmd_timer);
97     btstack_run_loop_set_timer_handler(&connection->press_and_hold_cmd_timer, avrcp_press_and_hold_timeout_handler);
98     btstack_run_loop_set_timer_context(&connection->press_and_hold_cmd_timer, connection);
99     btstack_run_loop_set_timer(&connection->press_and_hold_cmd_timer, 2000); // 2 seconds timeout
100     btstack_run_loop_add_timer(&connection->press_and_hold_cmd_timer);
101 }
102 
103 static void avrcp_press_and_hold_timer_stop(avrcp_connection_t * connection){
104     connection->continuous_fast_forward_cmd = 0;
105     btstack_run_loop_remove_timer(&connection->press_and_hold_cmd_timer);
106 }
107 
108 static uint8_t request_pass_through_release_control_cmd(avrcp_connection_t * connection){
109     connection->state = AVCTP_W2_SEND_RELEASE_COMMAND;
110     if (connection->continuous_fast_forward_cmd){
111         avrcp_press_and_hold_timer_stop(connection);
112     }
113     connection->cmd_operands[0] = 0x80 | connection->cmd_operands[0];
114     connection->transaction_label++;
115     avrcp_request_can_send_now(connection, connection->l2cap_signaling_cid);
116     return ERROR_CODE_SUCCESS;
117 }
118 
119 static inline uint8_t request_pass_through_press_control_cmd(uint16_t avrcp_cid, avrcp_operation_id_t opid, uint16_t playback_speed, uint8_t continuous_fast_forward_cmd, avrcp_context_t * context){
120     avrcp_connection_t * connection = get_avrcp_connection_for_avrcp_cid(avrcp_cid, context);
121     if (!connection){
122         log_error("avrcp: could not find a connection.");
123         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
124     }
125     if (connection->state != AVCTP_CONNECTION_OPENED) return ERROR_CODE_COMMAND_DISALLOWED;
126     connection->state = AVCTP_W2_SEND_PRESS_COMMAND;
127     connection->command_opcode =  AVRCP_CMD_OPCODE_PASS_THROUGH;
128     connection->command_type = AVRCP_CTYPE_CONTROL;
129     connection->subunit_type = AVRCP_SUBUNIT_TYPE_PANEL;
130     connection->subunit_id =   AVRCP_SUBUNIT_ID;
131     connection->cmd_operands_length = 0;
132 
133     connection->continuous_fast_forward_cmd = continuous_fast_forward_cmd;
134     connection->cmd_operands_length = 2;
135     connection->cmd_operands[0] = opid;
136     if (playback_speed > 0){
137         connection->cmd_operands[2] = playback_speed;
138         connection->cmd_operands_length++;
139     }
140     connection->cmd_operands[1] = connection->cmd_operands_length - 2;
141 
142     if (connection->continuous_fast_forward_cmd){
143         avrcp_press_and_hold_timer_start(connection);
144     }
145 
146     connection->transaction_label++;
147     avrcp_request_can_send_now(connection, connection->l2cap_signaling_cid);
148     return ERROR_CODE_SUCCESS;
149 }
150 
151 static uint8_t request_single_pass_through_press_control_cmd(uint16_t avrcp_cid, avrcp_operation_id_t opid, uint16_t playback_speed){
152     return request_pass_through_press_control_cmd(avrcp_cid, opid, playback_speed, 0, &avrcp_controller_context);
153 }
154 
155 static uint8_t request_continuous_pass_through_press_control_cmd(uint16_t avrcp_cid, avrcp_operation_id_t opid, uint16_t playback_speed){
156     return request_pass_through_press_control_cmd(avrcp_cid, opid, playback_speed, 1, &avrcp_controller_context);
157 }
158 
159 static int avrcp_send_cmd(uint16_t cid, avrcp_connection_t * connection){
160     uint8_t command[30];
161     int pos = 0;
162     // transport header
163     // Transaction label | Packet_type | C/R | IPID (1 == invalid profile identifier)
164     command[pos++] = (connection->transaction_label << 4) | (AVRCP_SINGLE_PACKET << 2) | (AVRCP_COMMAND_FRAME << 1) | 0;
165     // Profile IDentifier (PID)
166     command[pos++] = BLUETOOTH_SERVICE_CLASS_AV_REMOTE_CONTROL >> 8;
167     command[pos++] = BLUETOOTH_SERVICE_CLASS_AV_REMOTE_CONTROL & 0x00FF;
168 
169     // command_type
170     command[pos++] = connection->command_type;
171     // subunit_type | subunit ID
172     command[pos++] = (connection->subunit_type << 3) | connection->subunit_id;
173     // opcode
174     command[pos++] = (uint8_t)connection->command_opcode;
175     // operands
176     memcpy(command+pos, connection->cmd_operands, connection->cmd_operands_length);
177     pos += connection->cmd_operands_length;
178 
179     return l2cap_send(cid, command, pos);
180 }
181 
182 static int avrcp_register_notification(avrcp_connection_t * connection, avrcp_notification_event_id_t event_id){
183     if (connection->notifications_to_deregister & (1 << event_id)) return 0;
184     if (connection->notifications_enabled & (1 << event_id)) return 0;
185     if (connection->notifications_to_register & (1 << event_id)) return 0;
186     connection->notifications_to_register |= (1 << event_id);
187     avrcp_request_can_send_now(connection, connection->l2cap_signaling_cid);
188     return 1;
189 }
190 
191 static void avrcp_prepare_notification(avrcp_connection_t * connection, avrcp_notification_event_id_t event_id){
192     connection->transaction_label++;
193     connection->command_opcode = AVRCP_CMD_OPCODE_VENDOR_DEPENDENT;
194     connection->command_type = AVRCP_CTYPE_NOTIFY;
195     connection->subunit_type = AVRCP_SUBUNIT_TYPE_PANEL;
196     connection->subunit_id = AVRCP_SUBUNIT_ID;
197     int pos = 0;
198     big_endian_store_24(connection->cmd_operands, pos, BT_SIG_COMPANY_ID);
199     pos += 3;
200     connection->cmd_operands[pos++] = AVRCP_PDU_ID_REGISTER_NOTIFICATION;
201     connection->cmd_operands[pos++] = 0;                     // reserved(upper 6) | packet_type -> 0
202     big_endian_store_16(connection->cmd_operands, pos, 5);     // parameter length
203     pos += 2;
204     connection->cmd_operands[pos++] = event_id;
205     big_endian_store_32(connection->cmd_operands, pos, 0);
206     pos += 4;
207     connection->cmd_operands_length = pos;
208     // AVRCP_SPEC_V14.pdf 166
209     // answer page 61
210 }
211 
212 
213 static void avrcp_parser_reset(avrcp_connection_t * connection){
214     connection->list_offset = 0;
215     connection->num_attributes = 0;
216     connection->num_parsed_attributes = 0;
217     connection->parser_attribute_header_pos = 0;
218     connection->parser_state = AVRCP_PARSER_IDLE;
219 }
220 
221 static void avrcp_controller_emit_now_playing_info_event_done(btstack_packet_handler_t callback, uint16_t avrcp_cid, uint8_t ctype, uint8_t status){
222     uint8_t event[7];
223     int pos = 0;
224     event[pos++] = HCI_EVENT_AVRCP_META;
225     event[pos++] = sizeof(event) - 2;
226     event[pos++] = AVRCP_SUBEVENT_NOW_PLAYING_INFO_DONE;
227     little_endian_store_16(event, pos, avrcp_cid);
228     pos += 2;
229     event[pos++] = ctype;
230     event[pos++] = status;
231     // printf_hexdump(event, pos);
232     (*callback)(HCI_EVENT_PACKET, 0, event, pos);
233 }
234 
235 static void avrcp_controller_emit_now_playing_info_event(btstack_packet_handler_t callback, uint16_t avrcp_cid, uint8_t ctype, avrcp_media_attribute_id_t attr_id, uint8_t * value, uint16_t value_len){
236     uint8_t event[HCI_EVENT_BUFFER_SIZE];
237     int pos = 0;
238     event[pos++] = HCI_EVENT_AVRCP_META;
239     // reserve one byte for subevent type and data len
240     int data_len_pos = pos;
241     pos++;
242     int subevent_type_pos = pos;
243     pos++;
244     little_endian_store_16(event, pos, avrcp_cid);
245     pos += 2;
246     event[pos++] = ctype;
247 
248     switch (attr_id){
249         case AVRCP_MEDIA_ATTR_TITLE:
250             event[subevent_type_pos] = AVRCP_SUBEVENT_NOW_PLAYING_TITLE_INFO;
251             event[pos++] = value_len;
252             memcpy(event+pos, value, value_len);
253             break;
254         case AVRCP_MEDIA_ATTR_ARTIST:
255             event[subevent_type_pos] = AVRCP_SUBEVENT_NOW_PLAYING_ARTIST_INFO;
256             event[pos++] = value_len;
257             memcpy(event+pos, value, value_len);
258             break;
259         case AVRCP_MEDIA_ATTR_ALBUM:
260             event[subevent_type_pos] = AVRCP_SUBEVENT_NOW_PLAYING_ALBUM_INFO;
261             event[pos++] = value_len;
262             memcpy(event+pos, value, value_len);
263             break;
264         case AVRCP_MEDIA_ATTR_GENRE:
265             event[subevent_type_pos] = AVRCP_SUBEVENT_NOW_PLAYING_GENRE_INFO;
266             event[pos++] = value_len;
267             memcpy(event+pos, value, value_len);
268             break;
269         case AVRCP_MEDIA_ATTR_SONG_LENGTH_MS:
270             event[subevent_type_pos] = AVRCP_SUBEVENT_NOW_PLAYING_SONG_LENGTH_MS_INFO;
271             if (value){
272                 little_endian_store_32(event, pos, btstack_atoi((char *)value));
273             } else {
274                 little_endian_store_32(event, pos, 0);
275             }
276             pos += 4;
277             break;
278         case AVRCP_MEDIA_ATTR_TRACK:
279             event[subevent_type_pos] = AVRCP_SUBEVENT_NOW_PLAYING_TRACK_INFO;
280             if (value){
281                 event[pos++] = btstack_atoi((char *)value);
282             } else {
283                 event[pos++] = 0;
284             }
285             break;
286         case AVRCP_MEDIA_ATTR_TOTAL_TRACKS:
287             event[subevent_type_pos] = AVRCP_SUBEVENT_NOW_PLAYING_TOTAL_TRACKS_INFO;
288             if (value){
289                 event[pos++] = btstack_atoi((char *)value);
290             } else {
291                 event[pos++] = 0;
292             }
293             break;
294         default:
295             break;
296     }
297     event[data_len_pos] = pos - 2;
298     // printf("send attr len %d,  value %s\n", value_len, value);
299     (*callback)(HCI_EVENT_PACKET, 0, event, pos);
300 }
301 
302 static void avrcp_parser_process_byte(uint8_t byte, avrcp_connection_t * connection, avrcp_command_type_t ctype){
303     switch(connection->parser_state){
304         case AVRCP_PARSER_GET_ATTRIBUTE_HEADER:
305             if (connection->parser_attribute_header_pos < AVRCP_ATTRIBUTE_HEADER_LEN) {
306                 connection->parser_attribute_header[connection->parser_attribute_header_pos++] = byte;
307                 connection->list_offset++;
308                 break;
309             }
310             connection->attribute_value_len = btstack_min(big_endian_read_16(connection->parser_attribute_header, 6), AVRCP_MAX_ATTRIBUTTE_SIZE );
311             // printf(" attr id %d, len to read %d, total len %d  \n", big_endian_read_32(connection->parser_attribute_header, 0), connection->attribute_value_len, big_endian_read_16(connection->parser_attribute_header, 6));
312             connection->parser_state = AVRCP_PARSER_GET_ATTRIBUTE_VALUE;
313             break;
314         case AVRCP_PARSER_GET_ATTRIBUTE_VALUE:{
315             if (connection->attribute_value_offset < connection->attribute_value_len){
316                 connection->attribute_value[connection->attribute_value_offset++] = byte;
317                 connection->list_offset++;
318                 break;
319             }
320             // TODO emit event
321             uint32_t attribute_id = big_endian_read_32(connection->parser_attribute_header, 0);
322             if (attribute_id > AVRCP_MEDIA_ATTR_NONE && attribute_id <= AVRCP_MEDIA_ATTR_SONG_LENGTH_MS){
323                 avrcp_controller_emit_now_playing_info_event(avrcp_controller_context.avrcp_callback, connection->avrcp_cid, ctype, attribute_id, connection->attribute_value, connection->attribute_value_len);
324             }
325 
326             if (connection->attribute_value_offset < big_endian_read_16(connection->parser_attribute_header, 6)){
327                 // printf("parse until end of valuE, and ignore it\n");
328                 connection->parser_state = AVRCP_PARSER_IGNORE_ATTRIBUTE_VALUE;
329                 break;
330             }
331 
332             if (connection->list_offset == connection->list_size){
333                 avrcp_parser_reset(connection);
334                 avrcp_controller_emit_now_playing_info_event_done(avrcp_controller_context.avrcp_callback, connection->avrcp_cid, ctype, 0);
335                 break;
336             }
337 
338             connection->parser_state = AVRCP_PARSER_GET_ATTRIBUTE_HEADER;
339             connection->parser_attribute_header_pos = 0;
340             break;
341         }
342         case AVRCP_PARSER_IGNORE_ATTRIBUTE_VALUE:
343             if (connection->attribute_value_offset < big_endian_read_16(connection->parser_attribute_header, 6)){
344                 connection->list_offset++;
345                 connection->attribute_value_offset++;
346                 break;
347             }
348             // printf("read %d, total %d\n", connection->attribute_value_offset, big_endian_read_16(connection->parser_attribute_header, 6));
349 
350             if (connection->list_offset == connection->list_size){
351                 avrcp_parser_reset(connection);
352                 avrcp_controller_emit_now_playing_info_event_done(avrcp_controller_context.avrcp_callback, connection->avrcp_cid, ctype, 0);
353                 break;
354             }
355             connection->parser_state = AVRCP_PARSER_GET_ATTRIBUTE_HEADER;
356             connection->parser_attribute_header_pos = 0;
357             break;
358         default:
359             break;
360     }
361 }
362 
363 static void avrcp_source_parse_and_emit_element_attrs(uint8_t * packet, uint16_t num_bytes_to_read, avrcp_connection_t * connection, avrcp_command_type_t ctype){
364     int i;
365     for (i=0;i<num_bytes_to_read;i++){
366         avrcp_parser_process_byte(packet[i], connection, ctype);
367     }
368 }
369 
370 static uint8_t avrcp_controller_request_abort_continuation(avrcp_connection_t * connection){
371     connection->state = AVCTP_W2_SEND_COMMAND;
372     connection->transaction_label++;
373     connection->command_opcode = AVRCP_CMD_OPCODE_VENDOR_DEPENDENT;
374     connection->command_type = AVRCP_CTYPE_CONTROL;
375     connection->subunit_type = AVRCP_SUBUNIT_TYPE_PANEL;
376     connection->subunit_id = AVRCP_SUBUNIT_ID;
377     int pos = 0;
378     big_endian_store_24(connection->cmd_operands, pos, BT_SIG_COMPANY_ID);
379     pos += 3;
380     connection->cmd_operands[pos++] = AVRCP_PDU_ID_REQUEST_ABORT_CONTINUING_RESPONSE; // PDU ID
381     connection->cmd_operands[pos++] = 0;
382     // Parameter Length
383     connection->cmd_operands_length = 8;
384     big_endian_store_16(connection->cmd_operands, pos, 1);
385     pos += 2;
386     connection->cmd_operands[pos++] = AVRCP_PDU_ID_GET_ELEMENT_ATTRIBUTES;
387     avrcp_request_can_send_now(connection, connection->l2cap_signaling_cid);
388     return ERROR_CODE_SUCCESS;
389 }
390 
391 
392 static uint8_t avrcp_controller_request_continue_response(avrcp_connection_t * connection){
393     connection->state = AVCTP_W2_SEND_COMMAND;
394     connection->transaction_label++;
395     connection->command_opcode = AVRCP_CMD_OPCODE_VENDOR_DEPENDENT;
396     connection->command_type = AVRCP_CTYPE_CONTROL;
397     connection->subunit_type = AVRCP_SUBUNIT_TYPE_PANEL;
398     connection->subunit_id = AVRCP_SUBUNIT_ID;
399     int pos = 0;
400     big_endian_store_24(connection->cmd_operands, pos, BT_SIG_COMPANY_ID);
401     pos += 3;
402     connection->cmd_operands[pos++] = AVRCP_PDU_ID_REQUEST_CONTINUING_RESPONSE; // PDU ID
403     connection->cmd_operands[pos++] = 0;
404     // Parameter Length
405     connection->cmd_operands_length = 8;
406     big_endian_store_16(connection->cmd_operands, pos, 1);
407     pos += 2;
408     connection->cmd_operands[pos++] = AVRCP_PDU_ID_GET_ELEMENT_ATTRIBUTES;
409     avrcp_request_can_send_now(connection, connection->l2cap_signaling_cid);
410     return ERROR_CODE_SUCCESS;
411 }
412 
413 static void avrcp_handle_l2cap_data_packet_for_signaling_connection(avrcp_connection_t * connection, uint8_t *packet, uint16_t size){
414     uint8_t operands[20];
415     uint8_t opcode;
416     int     pos = 3;
417     // uint8_t transport_header = packet[0];
418     // uint8_t transaction_label = transport_header >> 4;
419     // uint8_t packet_type = (transport_header & 0x0F) >> 2;
420     // uint8_t frame_type = (transport_header & 0x03) >> 1;
421     // uint8_t ipid = transport_header & 0x01;
422     // uint8_t byte_value = packet[2];
423     // uint16_t pid = (byte_value << 8) | packet[2];
424 
425     avrcp_command_type_t ctype = (avrcp_command_type_t) packet[pos++];
426     uint8_t byte_value = packet[pos++];
427     avrcp_subunit_type_t subunit_type = (avrcp_subunit_type_t) (byte_value >> 3);
428     avrcp_subunit_type_t subunit_id = (avrcp_subunit_type_t)   (byte_value & 0x07);
429     opcode = packet[pos++];
430 
431     // printf("    Transport header 0x%02x (transaction_label %d, packet_type %d, frame_type %d, ipid %d), pid 0x%4x\n",
432     //     transport_header, transaction_label, packet_type, frame_type, ipid, pid);
433     // // printf_hexdump(packet+pos, size-pos);
434 
435     uint8_t pdu_id;
436     uint16_t param_length;
437     switch (avrcp_cmd_opcode(packet,size)){
438         case AVRCP_CMD_OPCODE_SUBUNIT_INFO:{
439             if (connection->state != AVCTP_W2_RECEIVE_RESPONSE) return;
440             connection->state = AVCTP_CONNECTION_OPENED;
441             // operands:
442             memcpy(operands, packet+pos, 5);
443             uint8_t unit_type = operands[1] >> 3;
444             uint8_t max_subunit_ID = operands[1] & 0x07;
445             log_info("    SUBUNIT INFO response: ctype 0x%02x (0C), subunit_type 0x%02x (1F), subunit_id 0x%02x (07), opcode 0x%02x (30), unit_type 0x%02x, max_subunit_ID %d", ctype, subunit_type, subunit_id, opcode, unit_type, max_subunit_ID);
446             break;
447         }
448         case AVRCP_CMD_OPCODE_UNIT_INFO:{
449             if (connection->state != AVCTP_W2_RECEIVE_RESPONSE) return;
450             connection->state = AVCTP_CONNECTION_OPENED;
451             // operands:
452             memcpy(operands, packet+pos, 5);
453             uint8_t unit_type = operands[1] >> 3;
454             uint8_t unit = operands[1] & 0x07;
455             uint32_t company_id = operands[2] << 16 | operands[3] << 8 | operands[4];
456             log_info("    UNIT INFO response: ctype 0x%02x (0C), subunit_type 0x%02x (1F), subunit_id 0x%02x (07), opcode 0x%02x (30), unit_type 0x%02x, unit %d, company_id 0x%06" PRIx32,
457                 ctype, subunit_type, subunit_id, opcode, unit_type, unit, company_id);
458             break;
459         }
460         case AVRCP_CMD_OPCODE_VENDOR_DEPENDENT:
461             if (size - pos < 7) {
462                 log_error("avrcp: wrong packet size");
463                 return;
464             };
465             // operands:
466             memcpy(operands, packet+pos, 7);
467             pos += 7;
468             // uint32_t company_id = operands[0] << 16 | operands[1] << 8 | operands[2];
469             pdu_id = operands[3];
470 
471             if (connection->state != AVCTP_W2_RECEIVE_RESPONSE && pdu_id != AVRCP_PDU_ID_REGISTER_NOTIFICATION){
472                 log_info("AVRCP_CMD_OPCODE_VENDOR_DEPENDENT state %d", connection->state);
473                 return;
474             }
475             connection->state = AVCTP_CONNECTION_OPENED;
476 
477 
478             // uint8_t unit_type = operands[4] >> 3;
479             // uint8_t unit = operands[4] & 0x07;
480             param_length = big_endian_read_16(operands, 5);
481 
482             // printf("    VENDOR DEPENDENT response: ctype 0x%02x (0C), subunit_type 0x%02x (1F), subunit_id 0x%02x (07), opcode 0x%02x (30), unit_type 0x%02x, unit %d, company_id 0x%06x\n",
483             //     ctype, subunit_type, subunit_id, opcode, unit_type, unit, company_id );
484 
485             // if (ctype == AVRCP_CTYPE_RESPONSE_INTERIM) return;
486             log_info("        VENDOR DEPENDENT response: pdu id 0x%02x, param_length %d, status %s", pdu_id, param_length, avrcp_ctype2str(ctype));
487             switch (pdu_id){
488                 case AVRCP_PDU_ID_GetCurrentPlayerApplicationSettingValue:{
489                     uint8_t num_attributes = packet[pos++];
490                     int i;
491                     avrcp_repeat_mode_t  repeat_mode =  AVRCP_REPEAT_MODE_INVALID;
492                     avrcp_shuffle_mode_t shuffle_mode = AVRCP_SHUFFLE_MODE_INVALID;
493                     for (i = 0; i < num_attributes; i++){
494                         uint8_t attribute_id    = packet[pos++];
495                         uint8_t value = packet[pos++];
496                         switch (attribute_id){
497                             case 0x02:
498                                 repeat_mode = (avrcp_repeat_mode_t) value;
499                                 break;
500                             case 0x03:
501                                 shuffle_mode = (avrcp_shuffle_mode_t) value;
502                                 break;
503                             default:
504                                 break;
505                         }
506                     }
507                     avrcp_emit_repeat_and_shuffle_mode(avrcp_controller_context.avrcp_callback, connection->avrcp_cid, ctype, repeat_mode, shuffle_mode);
508                     break;
509                 }
510                 case AVRCP_PDU_ID_SetPlayerApplicationSettingValue:{
511                     uint8_t event[6];
512                     int offset = 0;
513                     event[offset++] = HCI_EVENT_AVRCP_META;
514                     event[offset++] = sizeof(event) - 2;
515                     event[offset++] = AVRCP_SUBEVENT_PLAYER_APPLICATION_VALUE_RESPONSE;
516                     little_endian_store_16(event, offset, connection->avrcp_cid);
517                     offset += 2;
518                     event[offset++] = ctype;
519                     (*avrcp_controller_context.avrcp_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
520                     break;
521                 }
522                 case AVRCP_PDU_ID_SET_ABSOLUTE_VOLUME:{
523                     uint8_t event[7];
524                     int offset = 0;
525                     event[offset++] = HCI_EVENT_AVRCP_META;
526                     event[offset++] = sizeof(event) - 2;
527                     event[offset++] = AVRCP_SUBEVENT_SET_ABSOLUTE_VOLUME_RESPONSE;
528                     little_endian_store_16(event, offset, connection->avrcp_cid);
529                     offset += 2;
530                     event[offset++] = ctype;
531                     event[offset++] = packet[pos++];
532                     (*avrcp_controller_context.avrcp_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
533                     break;
534                 }
535                 case AVRCP_PDU_ID_GET_CAPABILITIES:{
536                     avrcp_capability_id_t capability_id = (avrcp_capability_id_t) packet[pos++];
537                     uint8_t capability_count = packet[pos++];
538                     int i;
539                     switch (capability_id){
540                         case AVRCP_CAPABILITY_ID_COMPANY:
541                             // log_info("Supported companies %d: ", capability_count);
542                             for (i = 0; i < capability_count; i++){
543                                 uint32_t company_id = big_endian_read_24(packet, pos);
544                                 pos += 3;
545                                 log_info("  0x%06" PRIx32 ", ", company_id);
546                             }
547                             break;
548                         case AVRCP_CAPABILITY_ID_EVENT:
549                             // log_info("Supported events %d: ", capability_count);
550                             for (i = 0; i < capability_count; i++){
551                                 uint8_t event_id = packet[pos++];
552                                 log_info("  0x%02x %s", event_id, avrcp_event2str(event_id));
553                             }
554                             break;
555                     }
556                     break;
557                 }
558                 case AVRCP_PDU_ID_GET_PLAY_STATUS:{
559                     uint32_t song_length = big_endian_read_32(packet, pos);
560                     pos += 4;
561                     uint32_t song_position = big_endian_read_32(packet, pos);
562                     pos += 4;
563                     uint8_t play_status = packet[pos];
564                     // log_info("        GET_PLAY_STATUS length 0x%04X, position 0x%04X, status %s", song_length, song_position, avrcp_play_status2str(play_status));
565 
566                     uint8_t event[15];
567                     int offset = 0;
568                     event[offset++] = HCI_EVENT_AVRCP_META;
569                     event[offset++] = sizeof(event) - 2;
570                     event[offset++] = AVRCP_SUBEVENT_PLAY_STATUS;
571                     little_endian_store_16(event, offset, connection->avrcp_cid);
572                     offset += 2;
573                     event[offset++] = ctype;
574                     little_endian_store_32(event, offset, song_length);
575                     offset += 4;
576                     little_endian_store_32(event, offset, song_position);
577                     offset += 4;
578                     event[offset++] = play_status;
579                     (*avrcp_controller_context.avrcp_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
580                     break;
581                 }
582                 case AVRCP_PDU_ID_REGISTER_NOTIFICATION:{
583                     avrcp_notification_event_id_t  event_id = (avrcp_notification_event_id_t) packet[pos++];
584                     uint16_t event_mask = (1 << event_id);
585                     uint16_t reset_event_mask = ~event_mask;
586                     switch (ctype){
587                         case AVRCP_CTYPE_RESPONSE_INTERIM:
588                             // register as enabled
589                             connection->notifications_enabled |= event_mask;
590                             // printf("INTERIM notifications_enabled 0x%2x, notifications_to_register 0x%2x\n", connection->notifications_enabled,  connection->notifications_to_register);
591                             break;
592                         case AVRCP_CTYPE_RESPONSE_CHANGED_STABLE:
593                             // received change, event is considered deregistered
594                             // we are re-enabling it automatically, if it is not
595                             // explicitly disabled
596                             connection->notifications_enabled &= reset_event_mask;
597                             if (! (connection->notifications_to_deregister & event_mask)){
598                                 avrcp_register_notification(connection, event_id);
599                                 // printf("CHANGED_STABLE notifications_enabled 0x%2x, notifications_to_register 0x%2x\n", connection->notifications_enabled,  connection->notifications_to_register);
600                             } else {
601                                 connection->notifications_to_deregister &= reset_event_mask;
602                             }
603                             break;
604                         default:
605                             connection->notifications_to_register &= reset_event_mask;
606                             connection->notifications_enabled &= reset_event_mask;
607                             connection->notifications_to_deregister &= reset_event_mask;
608                             break;
609                     }
610 
611                     switch (event_id){
612                         case AVRCP_NOTIFICATION_EVENT_PLAYBACK_STATUS_CHANGED:{
613                             uint8_t event[7];
614                             int offset = 0;
615                             event[offset++] = HCI_EVENT_AVRCP_META;
616                             event[offset++] = sizeof(event) - 2;
617                             event[offset++] = AVRCP_SUBEVENT_NOTIFICATION_PLAYBACK_STATUS_CHANGED;
618                             little_endian_store_16(event, offset, connection->avrcp_cid);
619                             offset += 2;
620                             event[offset++] = ctype;
621                             event[offset++] = packet[pos];
622                             (*avrcp_controller_context.avrcp_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
623                             break;
624                         }
625                         case AVRCP_NOTIFICATION_EVENT_TRACK_CHANGED:{
626                             uint8_t event[6];
627                             int offset = 0;
628                             event[offset++] = HCI_EVENT_AVRCP_META;
629                             event[offset++] = sizeof(event) - 2;
630                             event[offset++] = AVRCP_SUBEVENT_NOTIFICATION_TRACK_CHANGED;
631                             little_endian_store_16(event, offset, connection->avrcp_cid);
632                             offset += 2;
633                             event[offset++] = ctype;
634                             (*avrcp_controller_context.avrcp_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
635                             break;
636                         }
637                         case AVRCP_NOTIFICATION_EVENT_NOW_PLAYING_CONTENT_CHANGED:{
638                             uint8_t event[6];
639                             int offset = 0;
640                             event[offset++] = HCI_EVENT_AVRCP_META;
641                             event[offset++] = sizeof(event) - 2;
642                             event[offset++] = AVRCP_SUBEVENT_NOTIFICATION_NOW_PLAYING_CONTENT_CHANGED;
643                             little_endian_store_16(event, offset, connection->avrcp_cid);
644                             offset += 2;
645                             event[offset++] = ctype;
646                             (*avrcp_controller_context.avrcp_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
647                             break;
648                         }
649                         case AVRCP_NOTIFICATION_EVENT_AVAILABLE_PLAYERS_CHANGED:{
650                             uint8_t event[6];
651                             int offset = 0;
652                             event[offset++] = HCI_EVENT_AVRCP_META;
653                             event[offset++] = sizeof(event) - 2;
654                             event[offset++] = AVRCP_SUBEVENT_NOTIFICATION_AVAILABLE_PLAYERS_CHANGED;
655                             little_endian_store_16(event, offset, connection->avrcp_cid);
656                             offset += 2;
657                             event[offset++] = ctype;
658                             (*avrcp_controller_context.avrcp_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
659                             break;
660                         }
661                         case AVRCP_NOTIFICATION_EVENT_VOLUME_CHANGED:{
662                             uint8_t event[7];
663                             int offset = 0;
664                             event[offset++] = HCI_EVENT_AVRCP_META;
665                             event[offset++] = sizeof(event) - 2;
666                             event[offset++] = AVRCP_SUBEVENT_NOTIFICATION_VOLUME_CHANGED;
667                             little_endian_store_16(event, offset, connection->avrcp_cid);
668                             offset += 2;
669                             event[offset++] = ctype;
670                             event[offset++] = packet[pos++] & 0x7F;
671                             (*avrcp_controller_context.avrcp_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
672                             break;
673                         }
674                         // case AVRCP_NOTIFICATION_EVENT_PLAYER_APPLICATION_SETTING_CHANGED:{
675                         //     uint8_t num_PlayerApplicationSettingAttributes = packet[pos++];
676                         //     int i;
677                         //     for (i = 0; i < num_PlayerApplicationSettingAttributes; i++){
678                         //         uint8_t PlayerApplicationSetting_AttributeID = packet[pos++];
679                         //         uint8_t PlayerApplicationSettingValueID = packet[pos++];
680                         //     }
681                         //     break;
682                         // }
683                         // case AVRCP_NOTIFICATION_EVENT_ADDRESSED_PLAYER_CHANGED:
684                         //     uint16_t player_id = big_endian_read_16(packet, pos);
685                         //     pos += 2;
686                         //     uint16_t uid_counter = big_endian_read_16(packet, pos);
687                         //     pos += 2;
688                         //     break;
689                         // case AVRCP_NOTIFICATION_EVENT_UIDS_CHANGED:
690                         //     uint16_t uid_counter = big_endian_read_16(packet, pos);
691                         //     pos += 2;
692                         //     break;
693                         default:
694                             log_info("avrcp: not implemented");
695                             break;
696                     }
697                     if (connection->notifications_to_register != 0){
698                         avrcp_request_can_send_now(connection, connection->l2cap_signaling_cid);
699                     }
700                     break;
701                 }
702 
703                 case AVRCP_PDU_ID_GET_ELEMENT_ATTRIBUTES:{
704                     avrcp_packet_type_t packet_type = operands[4] & 0x03;
705                     switch (packet_type){
706                         case AVRCP_START_PACKET:
707                         case AVRCP_SINGLE_PACKET:
708                             avrcp_parser_reset(connection);
709                             connection->list_size = param_length;
710                             connection->num_attributes = packet[pos++];
711                             // printf("AVRCP_PDU_ID_GET_ELEMENT_ATTRIBUTES num_attributes %d, total size %d, packet type 0x%02x \n", connection->num_attributes, connection->list_size, operands[4] & 0x03);
712                             connection->parser_state = AVRCP_PARSER_GET_ATTRIBUTE_HEADER;
713                             avrcp_source_parse_and_emit_element_attrs(packet+pos, size-pos, connection, ctype);
714 
715                             if (packet_type == AVRCP_START_PACKET){
716                                 if (connection->num_attributes == 1 && connection->parser_state == AVRCP_PARSER_IGNORE_ATTRIBUTE_VALUE){
717                                     avrcp_controller_request_abort_continuation(connection);
718                                 } else {
719                                     avrcp_controller_request_continue_response(connection);
720                                 }
721                             }
722                             break;
723                         case AVRCP_CONTINUE_PACKET:
724                             avrcp_source_parse_and_emit_element_attrs(packet+pos, size-pos, connection, ctype);
725                             avrcp_controller_request_continue_response(connection);
726                             break;
727                         case AVRCP_END_PACKET:
728                             avrcp_source_parse_and_emit_element_attrs(packet+pos, size-pos, connection, ctype);
729                             break;
730                     }
731                 }
732                 default:
733                     break;
734             }
735             break;
736         case AVRCP_CMD_OPCODE_PASS_THROUGH:{
737             // 0x80 | connection->cmd_operands[0]
738             uint8_t operation_id = packet[pos++];
739             switch (connection->state){
740                 case AVCTP_W2_RECEIVE_PRESS_RESPONSE:
741                     if (connection->continuous_fast_forward_cmd){
742                         connection->state = AVCTP_W4_STOP;
743                     } else {
744                         connection->state = AVCTP_W2_SEND_RELEASE_COMMAND;
745                     }
746                     break;
747                 case AVCTP_W2_RECEIVE_RESPONSE:
748                     connection->state = AVCTP_CONNECTION_OPENED;
749                     break;
750                 default:
751                     // check for notifications? move state transition down
752                     // log_info("AVRCP_CMD_OPCODE_PASS_THROUGH state %d\n", connection->state);
753                     break;
754             }
755             if (connection->state == AVCTP_W4_STOP){
756                 avrcp_emit_operation_status(avrcp_controller_context.avrcp_callback, AVRCP_SUBEVENT_OPERATION_START, connection->avrcp_cid, ctype, operation_id);
757             }
758             if (connection->state == AVCTP_CONNECTION_OPENED) {
759                 // RELEASE response
760                 operation_id = operation_id & 0x7F;
761                 avrcp_emit_operation_status(avrcp_controller_context.avrcp_callback, AVRCP_SUBEVENT_OPERATION_COMPLETE, connection->avrcp_cid, ctype, operation_id);
762             }
763             if (connection->state == AVCTP_W2_SEND_RELEASE_COMMAND){
764                 // PRESS response
765                 request_pass_through_release_control_cmd(connection);
766             }
767             break;
768         }
769         default:
770             break;
771     }
772 }
773 
774 static void avrcp_controller_handle_can_send_now(avrcp_connection_t * connection){
775     int i;
776     switch (connection->state){
777         case AVCTP_W2_SEND_PRESS_COMMAND:
778             connection->state = AVCTP_W2_RECEIVE_PRESS_RESPONSE;
779             avrcp_send_cmd(connection->l2cap_signaling_cid, connection);
780             break;
781         case AVCTP_W2_SEND_COMMAND:
782         case AVCTP_W2_SEND_RELEASE_COMMAND:
783             connection->state = AVCTP_W2_RECEIVE_RESPONSE;
784             avrcp_send_cmd(connection->l2cap_signaling_cid, connection);
785             break;
786         case AVCTP_CONNECTION_OPENED:
787             if (connection->notifications_to_register != 0){
788                 for (i = 1; i <= AVRCP_NOTIFICATION_EVENT_VOLUME_CHANGED; i++){
789                     if (connection->notifications_to_register & (1<<i)){
790                         connection->notifications_to_register &= ~ (1 << i);
791                         avrcp_prepare_notification(connection, (avrcp_notification_event_id_t) i);
792                         connection->state = AVCTP_W2_RECEIVE_RESPONSE;
793                         avrcp_send_cmd(connection->l2cap_signaling_cid, connection);
794                         return;
795                     }
796                 }
797             }
798             return;
799         default:
800             return;
801     }
802 }
803 
804 static void avrcp_controller_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
805     avrcp_connection_t * connection;
806 
807     switch (packet_type) {
808         case L2CAP_DATA_PACKET:
809             connection = get_avrcp_connection_for_l2cap_signaling_cid(channel, &avrcp_controller_context);
810             if (!connection) break;
811             avrcp_handle_l2cap_data_packet_for_signaling_connection(connection, packet, size);
812             break;
813         case HCI_EVENT_PACKET:
814             switch (hci_event_packet_get_type(packet)){
815                 case L2CAP_EVENT_CAN_SEND_NOW:
816                     connection = get_avrcp_connection_for_l2cap_signaling_cid(channel, &avrcp_controller_context);
817                     if (!connection) break;
818                     avrcp_controller_handle_can_send_now(connection);
819                     break;
820             default:
821                 avrcp_packet_handler(packet_type, channel, packet, size, &avrcp_controller_context);
822                 break;
823         }
824         default:
825             break;
826     }
827 }
828 
829 void avrcp_controller_init(void){
830     avrcp_controller_context.role = AVRCP_CONTROLLER;
831     avrcp_controller_context.connections = NULL;
832     avrcp_controller_context.packet_handler = avrcp_controller_packet_handler;
833     l2cap_register_service(&avrcp_controller_packet_handler, BLUETOOTH_PROTOCOL_AVCTP, 0xffff, LEVEL_0);
834 }
835 
836 void avrcp_controller_register_packet_handler(btstack_packet_handler_t callback){
837     if (callback == NULL){
838         log_error("avrcp_register_packet_handler called with NULL callback");
839         return;
840     }
841     avrcp_controller_context.avrcp_callback = callback;
842 }
843 
844 uint8_t avrcp_controller_connect(bd_addr_t bd_addr, uint16_t * avrcp_cid){
845     return avrcp_connect(bd_addr, &avrcp_controller_context, avrcp_cid);
846 }
847 
848 uint8_t avrcp_controller_unit_info(uint16_t avrcp_cid){
849     avrcp_connection_t * connection = get_avrcp_connection_for_avrcp_cid(avrcp_cid, &avrcp_controller_context);
850     if (!connection){
851         log_error("avrcp_unit_info: could not find a connection.");
852         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
853     }
854     if (connection->state != AVCTP_CONNECTION_OPENED) return ERROR_CODE_COMMAND_DISALLOWED;
855     connection->state = AVCTP_W2_SEND_COMMAND;
856 
857     connection->transaction_label++;
858     connection->command_opcode = AVRCP_CMD_OPCODE_UNIT_INFO;
859     connection->command_type = AVRCP_CTYPE_STATUS;
860     connection->subunit_type = AVRCP_SUBUNIT_TYPE_UNIT; //vendor unique
861     connection->subunit_id =   AVRCP_SUBUNIT_ID_IGNORE;
862     memset(connection->cmd_operands, 0xFF, connection->cmd_operands_length);
863     connection->cmd_operands_length = 5;
864     avrcp_request_can_send_now(connection, connection->l2cap_signaling_cid);
865     return ERROR_CODE_SUCCESS;
866 }
867 
868 uint8_t avrcp_controller_subunit_info(uint16_t avrcp_cid){
869     avrcp_connection_t * connection = get_avrcp_connection_for_avrcp_cid(avrcp_cid, &avrcp_controller_context);
870     if (!connection){
871         log_error("avrcp_unit_info: could not find a connection.");
872         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
873     }
874     if (connection->state != AVCTP_CONNECTION_OPENED) return ERROR_CODE_COMMAND_DISALLOWED;
875     connection->state = AVCTP_W2_SEND_COMMAND;
876 
877     connection->transaction_label++;
878     connection->command_opcode = AVRCP_CMD_OPCODE_SUBUNIT_INFO;
879     connection->command_type = AVRCP_CTYPE_STATUS;
880     connection->subunit_type = AVRCP_SUBUNIT_TYPE_UNIT; //vendor unique
881     connection->subunit_id =   AVRCP_SUBUNIT_ID_IGNORE;
882     memset(connection->cmd_operands, 0xFF, connection->cmd_operands_length);
883     connection->cmd_operands[0] = 7; // page: 0, extention_code: 7
884     connection->cmd_operands_length = 5;
885     avrcp_request_can_send_now(connection, connection->l2cap_signaling_cid);
886     return ERROR_CODE_SUCCESS;
887 }
888 
889 static uint8_t avrcp_controller_get_capabilities(uint16_t avrcp_cid, uint8_t capability_id){
890     avrcp_connection_t * connection = get_avrcp_connection_for_avrcp_cid(avrcp_cid, &avrcp_controller_context);
891     if (!connection){
892         log_error("avrcp_get_capabilities: could not find a connection.");
893         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
894     }
895     if (connection->state != AVCTP_CONNECTION_OPENED) return ERROR_CODE_COMMAND_DISALLOWED;
896     connection->state = AVCTP_W2_SEND_COMMAND;
897 
898     connection->transaction_label++;
899     connection->command_opcode = AVRCP_CMD_OPCODE_VENDOR_DEPENDENT;
900     connection->command_type = AVRCP_CTYPE_STATUS;
901     connection->subunit_type = AVRCP_SUBUNIT_TYPE_PANEL;
902     connection->subunit_id = AVRCP_SUBUNIT_ID;
903     big_endian_store_24(connection->cmd_operands, 0, BT_SIG_COMPANY_ID);
904     connection->cmd_operands[3] = AVRCP_PDU_ID_GET_CAPABILITIES; // PDU ID
905     connection->cmd_operands[4] = 0;
906     big_endian_store_16(connection->cmd_operands, 5, 1); // parameter length
907     connection->cmd_operands[7] = capability_id;                  // capability ID
908     connection->cmd_operands_length = 8;
909     avrcp_request_can_send_now(connection, connection->l2cap_signaling_cid);
910     return ERROR_CODE_SUCCESS;
911 }
912 
913 uint8_t avrcp_controller_get_supported_company_ids(uint16_t avrcp_cid){
914     return avrcp_controller_get_capabilities(avrcp_cid, AVRCP_CAPABILITY_ID_COMPANY);
915 }
916 
917 uint8_t avrcp_controller_get_supported_events(uint16_t avrcp_cid){
918     return avrcp_controller_get_capabilities(avrcp_cid, AVRCP_CAPABILITY_ID_EVENT);
919 }
920 
921 
922 uint8_t avrcp_controller_play(uint16_t avrcp_cid){
923     return request_single_pass_through_press_control_cmd(avrcp_cid, AVRCP_OPERATION_ID_PLAY, 0);
924 }
925 
926 uint8_t avrcp_controller_stop(uint16_t avrcp_cid){
927     return request_single_pass_through_press_control_cmd(avrcp_cid, AVRCP_OPERATION_ID_STOP, 0);
928 }
929 
930 uint8_t avrcp_controller_pause(uint16_t avrcp_cid){
931     return request_single_pass_through_press_control_cmd(avrcp_cid, AVRCP_OPERATION_ID_PAUSE, 0);
932 }
933 
934 uint8_t avrcp_controller_forward(uint16_t avrcp_cid){
935     return request_single_pass_through_press_control_cmd(avrcp_cid, AVRCP_OPERATION_ID_FORWARD, 0);
936 }
937 
938 uint8_t avrcp_controller_backward(uint16_t avrcp_cid){
939     return request_single_pass_through_press_control_cmd(avrcp_cid, AVRCP_OPERATION_ID_BACKWARD, 0);
940 }
941 
942 uint8_t avrcp_controller_start_rewind(uint16_t avrcp_cid){
943     return request_continuous_pass_through_press_control_cmd(avrcp_cid, AVRCP_OPERATION_ID_REWIND, 0);
944 }
945 
946 uint8_t avrcp_controller_volume_up(uint16_t avrcp_cid){
947     return request_single_pass_through_press_control_cmd(avrcp_cid, AVRCP_OPERATION_ID_VOLUME_UP, 0);
948 }
949 
950 uint8_t avrcp_controller_volume_down(uint16_t avrcp_cid){
951     return request_single_pass_through_press_control_cmd(avrcp_cid, AVRCP_OPERATION_ID_VOLUME_DOWN, 0);
952 }
953 
954 uint8_t avrcp_controller_mute(uint16_t avrcp_cid){
955     return request_single_pass_through_press_control_cmd(avrcp_cid, AVRCP_OPERATION_ID_MUTE, 0);
956 }
957 
958 uint8_t avrcp_controller_skip(uint16_t avrcp_cid){
959     return request_single_pass_through_press_control_cmd(avrcp_cid, AVRCP_OPERATION_ID_SKIP, 0);
960 }
961 
962 uint8_t avrcp_controller_stop_rewind(uint16_t avrcp_cid){
963     avrcp_connection_t * connection = get_avrcp_connection_for_avrcp_cid(avrcp_cid, &avrcp_controller_context);
964     if (!connection){
965         log_error("avrcp_stop_rewind: could not find a connection.");
966         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
967     }
968     if (connection->state != AVCTP_W4_STOP) return ERROR_CODE_COMMAND_DISALLOWED;
969     return request_pass_through_release_control_cmd(connection);
970 }
971 
972 uint8_t avrcp_controller_start_fast_forward(uint16_t avrcp_cid){
973     return request_continuous_pass_through_press_control_cmd(avrcp_cid, AVRCP_OPERATION_ID_FAST_FORWARD, 0);
974 }
975 
976 uint8_t avrcp_controller_fast_forward(uint16_t avrcp_cid){
977     return request_single_pass_through_press_control_cmd(avrcp_cid, AVRCP_OPERATION_ID_FAST_FORWARD, 0);
978 }
979 
980 uint8_t avrcp_controller_rewind(uint16_t avrcp_cid){
981     return request_single_pass_through_press_control_cmd(avrcp_cid, AVRCP_OPERATION_ID_REWIND, 0);
982 }
983 
984 
985 uint8_t avrcp_controller_stop_fast_forward(uint16_t avrcp_cid){
986     avrcp_connection_t * connection = get_avrcp_connection_for_avrcp_cid(avrcp_cid, &avrcp_controller_context);
987     if (!connection){
988         log_error("avrcp_stop_fast_forward: could not find a connection.");
989         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
990     }
991     if (connection->state != AVCTP_W4_STOP) return ERROR_CODE_COMMAND_DISALLOWED;
992     return request_pass_through_release_control_cmd(connection);
993 }
994 
995 uint8_t avrcp_controller_get_play_status(uint16_t avrcp_cid){
996     avrcp_connection_t * connection = get_avrcp_connection_for_avrcp_cid(avrcp_cid, &avrcp_controller_context);
997     if (!connection){
998         log_error("avrcp_get_play_status: could not find a connection.");
999         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
1000     }
1001     if (connection->state != AVCTP_CONNECTION_OPENED) return ERROR_CODE_COMMAND_DISALLOWED;
1002     connection->state = AVCTP_W2_SEND_COMMAND;
1003     connection->transaction_label++;
1004     connection->command_opcode = AVRCP_CMD_OPCODE_VENDOR_DEPENDENT;
1005     connection->command_type = AVRCP_CTYPE_STATUS;
1006     connection->subunit_type = AVRCP_SUBUNIT_TYPE_PANEL;
1007     connection->subunit_id = AVRCP_SUBUNIT_ID;
1008     big_endian_store_24(connection->cmd_operands, 0, BT_SIG_COMPANY_ID);
1009     connection->cmd_operands[3] = AVRCP_PDU_ID_GET_PLAY_STATUS;
1010     connection->cmd_operands[4] = 0;                     // reserved(upper 6) | packet_type -> 0
1011     big_endian_store_16(connection->cmd_operands, 5, 0); // parameter length
1012     connection->cmd_operands_length = 7;
1013     avrcp_request_can_send_now(connection, connection->l2cap_signaling_cid);
1014     return ERROR_CODE_SUCCESS;
1015 }
1016 
1017 uint8_t avrcp_controller_enable_notification(uint16_t avrcp_cid, avrcp_notification_event_id_t event_id){
1018     avrcp_connection_t * connection = get_avrcp_connection_for_avrcp_cid(avrcp_cid, &avrcp_controller_context);
1019     if (!connection){
1020         log_error("avrcp_get_play_status: could not find a connection.");
1021         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
1022     }
1023     avrcp_register_notification(connection, event_id);
1024     return ERROR_CODE_SUCCESS;
1025 }
1026 
1027 uint8_t avrcp_controller_disable_notification(uint16_t avrcp_cid, avrcp_notification_event_id_t event_id){
1028     avrcp_connection_t * connection = get_avrcp_connection_for_avrcp_cid(avrcp_cid, &avrcp_controller_context);
1029     if (!connection){
1030         log_error("avrcp_get_play_status: could not find a connection.");
1031         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
1032     }
1033     connection->notifications_to_deregister |= (1 << event_id);
1034     return ERROR_CODE_SUCCESS;
1035 }
1036 
1037 
1038 uint8_t avrcp_controller_get_now_playing_info(uint16_t avrcp_cid){
1039     avrcp_connection_t * connection = get_avrcp_connection_for_avrcp_cid(avrcp_cid, &avrcp_controller_context);
1040     if (!connection){
1041         log_error("avrcp_get_capabilities: could not find a connection.");
1042         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
1043     }
1044     if (connection->state != AVCTP_CONNECTION_OPENED) return ERROR_CODE_COMMAND_DISALLOWED;
1045     connection->state = AVCTP_W2_SEND_COMMAND;
1046 
1047     connection->transaction_label++;
1048     connection->command_opcode = AVRCP_CMD_OPCODE_VENDOR_DEPENDENT;
1049     connection->command_type = AVRCP_CTYPE_STATUS;
1050     connection->subunit_type = AVRCP_SUBUNIT_TYPE_PANEL;
1051     connection->subunit_id = AVRCP_SUBUNIT_ID;
1052     int pos = 0;
1053     big_endian_store_24(connection->cmd_operands, pos, BT_SIG_COMPANY_ID);
1054     pos += 3;
1055     connection->cmd_operands[pos++] = AVRCP_PDU_ID_GET_ELEMENT_ATTRIBUTES; // PDU ID
1056     connection->cmd_operands[pos++] = 0;
1057 
1058     // Parameter Length
1059     big_endian_store_16(connection->cmd_operands, pos, 9);
1060     pos += 2;
1061 
1062     // write 8 bytes value
1063     memset(connection->cmd_operands + pos, 0, 8); // identifier: PLAYING
1064     pos += 8;
1065 
1066     connection->cmd_operands[pos++] = 0; // attribute count, if 0 get all attributes
1067     // every attribute is 4 bytes long
1068 
1069     connection->cmd_operands_length = pos;
1070     avrcp_request_can_send_now(connection, connection->l2cap_signaling_cid);
1071     return ERROR_CODE_SUCCESS;
1072 }
1073 
1074 uint8_t avrcp_controller_set_absolute_volume(uint16_t avrcp_cid, uint8_t volume){
1075      avrcp_connection_t * connection = get_avrcp_connection_for_avrcp_cid(avrcp_cid, &avrcp_controller_context);
1076     if (!connection){
1077         log_error("avrcp_get_capabilities: could not find a connection.");
1078         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
1079     }
1080     if (connection->state != AVCTP_CONNECTION_OPENED) return ERROR_CODE_COMMAND_DISALLOWED;
1081     connection->state = AVCTP_W2_SEND_COMMAND;
1082 
1083     connection->transaction_label++;
1084     connection->command_opcode = AVRCP_CMD_OPCODE_VENDOR_DEPENDENT;
1085     connection->command_type = AVRCP_CTYPE_CONTROL;
1086     connection->subunit_type = AVRCP_SUBUNIT_TYPE_PANEL;
1087     connection->subunit_id = AVRCP_SUBUNIT_ID;
1088     int pos = 0;
1089     big_endian_store_24(connection->cmd_operands, pos, BT_SIG_COMPANY_ID);
1090     pos += 3;
1091     connection->cmd_operands[pos++] = AVRCP_PDU_ID_SET_ABSOLUTE_VOLUME; // PDU ID
1092     connection->cmd_operands[pos++] = 0;
1093 
1094     // Parameter Length
1095     big_endian_store_16(connection->cmd_operands, pos, 1);
1096     pos += 2;
1097     connection->cmd_operands[pos++] = volume;
1098 
1099     connection->cmd_operands_length = pos;
1100     avrcp_request_can_send_now(connection, connection->l2cap_signaling_cid);
1101     return ERROR_CODE_SUCCESS;
1102 }
1103 
1104 uint8_t avrcp_controller_query_shuffle_and_repeat_modes(uint16_t avrcp_cid){
1105     avrcp_connection_t * connection = get_avrcp_connection_for_avrcp_cid(avrcp_cid, &avrcp_controller_context);
1106     if (!connection){
1107         log_error("avrcp_get_capabilities: could not find a connection.");
1108         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
1109     }
1110     if (connection->state != AVCTP_CONNECTION_OPENED) return ERROR_CODE_COMMAND_DISALLOWED;
1111     connection->state = AVCTP_W2_SEND_COMMAND;
1112 
1113     connection->transaction_label++;
1114     connection->command_opcode = AVRCP_CMD_OPCODE_VENDOR_DEPENDENT;
1115     connection->command_type = AVRCP_CTYPE_STATUS;
1116     connection->subunit_type = AVRCP_SUBUNIT_TYPE_PANEL;
1117     connection->subunit_id = AVRCP_SUBUNIT_ID;
1118     big_endian_store_24(connection->cmd_operands, 0, BT_SIG_COMPANY_ID);
1119     connection->cmd_operands[3] = AVRCP_PDU_ID_GetCurrentPlayerApplicationSettingValue; // PDU ID
1120     connection->cmd_operands[4] = 0;
1121     big_endian_store_16(connection->cmd_operands, 5, 5); // parameter length
1122     connection->cmd_operands[7] = 4;                     // NumPlayerApplicationSettingAttributeID
1123     // PlayerApplicationSettingAttributeID1 AVRCP Spec, Appendix F, 133
1124     connection->cmd_operands[8]  = 0x01;    // equalizer  (1-OFF, 2-ON)
1125     connection->cmd_operands[9]  = 0x02;    // repeat     (1-off, 2-single track, 3-all tracks, 4-group repeat)
1126     connection->cmd_operands[10] = 0x03;    // shuffle    (1-off, 2-all tracks, 3-group shuffle)
1127     connection->cmd_operands[11] = 0x04;    // scan       (1-off, 2-all tracks, 3-group scan)
1128     connection->cmd_operands_length = 12;
1129     avrcp_request_can_send_now(connection, connection->l2cap_signaling_cid);
1130     return ERROR_CODE_SUCCESS;
1131 }
1132 
1133 static uint8_t avrcp_controller_set_current_player_application_setting_value(uint16_t avrcp_cid, uint8_t attr_id, uint8_t attr_value){
1134     avrcp_connection_t * connection = get_avrcp_connection_for_avrcp_cid(avrcp_cid, &avrcp_controller_context);
1135     if (!connection){
1136         log_error("avrcp_get_capabilities: could not find a connection.");
1137         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
1138     }
1139     if (connection->state != AVCTP_CONNECTION_OPENED) return ERROR_CODE_COMMAND_DISALLOWED;
1140     connection->state = AVCTP_W2_SEND_COMMAND;
1141 
1142     connection->transaction_label++;
1143     connection->command_opcode = AVRCP_CMD_OPCODE_VENDOR_DEPENDENT;
1144     connection->command_type = AVRCP_CTYPE_CONTROL;
1145     connection->subunit_type = AVRCP_SUBUNIT_TYPE_PANEL;
1146     connection->subunit_id = AVRCP_SUBUNIT_ID;
1147     int pos = 0;
1148     big_endian_store_24(connection->cmd_operands, pos, BT_SIG_COMPANY_ID);
1149     pos += 3;
1150     connection->cmd_operands[pos++] = AVRCP_PDU_ID_SetPlayerApplicationSettingValue; // PDU ID
1151     connection->cmd_operands[pos++] = 0;
1152     // Parameter Length
1153     big_endian_store_16(connection->cmd_operands, pos, 3);
1154     pos += 2;
1155     connection->cmd_operands[pos++] = 2;
1156     connection->cmd_operands_length = pos;
1157     connection->cmd_operands[pos++]  = attr_id;
1158     connection->cmd_operands[pos++]  = attr_value;
1159     connection->cmd_operands_length = pos;
1160     avrcp_request_can_send_now(connection, connection->l2cap_signaling_cid);
1161     return ERROR_CODE_SUCCESS;
1162 }
1163 
1164 uint8_t avrcp_controller_set_shuffle_mode(uint16_t avrcp_cid, avrcp_shuffle_mode_t mode){
1165     if (mode < AVRCP_SHUFFLE_MODE_OFF || mode > AVRCP_SHUFFLE_MODE_GROUP) return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
1166     return avrcp_controller_set_current_player_application_setting_value(avrcp_cid, 0x03, mode);
1167 }
1168 
1169 uint8_t avrcp_controller_set_repeat_mode(uint16_t avrcp_cid, avrcp_repeat_mode_t mode){
1170     if (mode < AVRCP_REPEAT_MODE_OFF || mode > AVRCP_REPEAT_MODE_GROUP) return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
1171     return avrcp_controller_set_current_player_application_setting_value(avrcp_cid, 0x02, mode);
1172 }
1173 
1174 uint8_t avrcp_controller_disconnect(uint16_t avrcp_cid){
1175     avrcp_connection_t * connection = get_avrcp_connection_for_avrcp_cid(avrcp_cid, &avrcp_controller_context);
1176     if (!connection){
1177         log_error("avrcp_get_capabilities: could not find a connection.");
1178         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
1179     }
1180     if (connection->state != AVCTP_CONNECTION_OPENED) return ERROR_CODE_COMMAND_DISALLOWED;
1181     if (connection->browsing_connection){
1182         if (connection->browsing_connection->state != AVCTP_CONNECTION_OPENED) return ERROR_CODE_COMMAND_DISALLOWED;
1183         l2cap_disconnect(connection->browsing_connection->l2cap_browsing_cid, 0);
1184     }
1185     l2cap_disconnect(connection->l2cap_signaling_cid, 0);
1186     return ERROR_CODE_SUCCESS;
1187 }
1188