xref: /btstack/example/a2dp_sink_demo.c (revision dbf84c8a4e5f19f37bf9128db249cb40829b9966)
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 BLUEKITCHEN
24  * GMBH 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__ "a2dp_sink_demo.c"
39 
40 /*
41  * a2dp_sink_demo.c
42  */
43 
44 // *****************************************************************************
45 /* EXAMPLE_START(a2dp_sink_demo): A2DP Sink - Receive Audio Stream and Control Playback
46  *
47  * @text This A2DP Sink example demonstrates how to use the A2DP Sink service to
48  * receive an audio data stream from a remote A2DP Source device. In addition,
49  * the AVRCP Controller is used to get information on currently played media,
50  * such are title, artist and album, as well as to control the playback,
51  * i.e. to play, stop, repeat, etc. If HAVE_BTSTACK_STDIN is set, press SPACE on
52  * the console to show the available AVDTP and AVRCP commands.
53  *
54  * @text To test with a remote device, e.g. a mobile phone,
55  * pair from the remote device with the demo, then start playing music on the remote device.
56  * Alternatively, set the device_addr_string to the Bluetooth address of your
57  * remote device in the code, and call connect from the UI.
58  *
59  * @text For more info on BTstack audio, see our blog post
60  * [A2DP Sink and Source on STM32 F4 Discovery Board](http://bluekitchen-gmbh.com/a2dp-sink-and-source-on-stm32-f4-discovery-board/).
61  *
62  */
63 // *****************************************************************************
64 
65 #include <inttypes.h>
66 #include <stdint.h>
67 #include <stdio.h>
68 #include <stdlib.h>
69 #include <string.h>
70 
71 #include "btstack.h"
72 #include "btstack_resample.h"
73 
74 //#define AVRCP_BROWSING_ENABLED
75 
76 // if volume control not supported by btstack_audio_sink, you can try to disable volume change notification
77 // to force the A2DP Source to reduce volume by attenuating the audio stream
78 #define SUPPORT_VOLUME_CHANGE_NOTIFICATION
79 
80 #ifdef HAVE_BTSTACK_STDIN
81 #include "btstack_stdin.h"
82 #endif
83 
84 #include "btstack_ring_buffer.h"
85 
86 #ifdef HAVE_POSIX_FILE_IO
87 #include "wav_util.h"
88 #define STORE_TO_SBC_FILE
89 #define STORE_TO_WAV_FILE
90 #endif
91 
92 #define NUM_CHANNELS 2
93 #define BYTES_PER_FRAME     (2*NUM_CHANNELS)
94 #define MAX_SBC_FRAME_SIZE 120
95 
96 // SBC Decoder for WAV file or live playback
97 static btstack_sbc_decoder_state_t state;
98 static btstack_sbc_mode_t mode = SBC_MODE_STANDARD;
99 
100 // ring buffer for SBC Frames
101 // below 30: add samples, 30-40: fine, above 40: drop samples
102 #define OPTIMAL_FRAMES_MIN 30
103 #define OPTIMAL_FRAMES_MAX 40
104 #define ADDITIONAL_FRAMES  20
105 static uint8_t sbc_frame_storage[(OPTIMAL_FRAMES_MAX + ADDITIONAL_FRAMES) * MAX_SBC_FRAME_SIZE];
106 static btstack_ring_buffer_t sbc_frame_ring_buffer;
107 static unsigned int sbc_frame_size;
108 
109 // rest buffer for not fully used sbc frames, with additional frames for resampling
110 static uint8_t decoded_audio_storage[(128+16) * BYTES_PER_FRAME];
111 static btstack_ring_buffer_t decoded_audio_ring_buffer;
112 
113 static int audio_stream_started;
114 
115 // temp storage of lower-layer request
116 static int16_t * request_buffer;
117 static int       request_frames;
118 
119 #define STORE_FROM_PLAYBACK
120 
121 // WAV File
122 #ifdef STORE_TO_WAV_FILE
123 static uint32_t audio_frame_count = 0;
124 static char * wav_filename = "a2dp_sink_demo.wav";
125 #endif
126 
127 #ifdef STORE_TO_SBC_FILE
128 static FILE * sbc_file;
129 static char * sbc_filename = "av2dp_sink_demo.sbc";
130 #endif
131 
132 typedef struct {
133     int reconfigure;
134 
135     int num_channels;
136     int sampling_frequency;
137     int block_length;
138     int subbands;
139     int min_bitpool_value;
140     int max_bitpool_value;
141     btstack_sbc_channel_mode_t      channel_mode;
142     btstack_sbc_allocation_method_t allocation_method;
143 } media_codec_configuration_sbc_t;
144 
145 static media_codec_configuration_sbc_t sbc_configuration;
146 static int volume_percentage = 0;
147 static avrcp_battery_status_t battery_status = AVRCP_BATTERY_STATUS_WARNING;
148 
149 #ifdef HAVE_BTSTACK_STDIN
150 // pts:
151 static const char * device_addr_string = "5C:F3:70:60:7B:87";
152 // mac 2013:  static const char * device_addr_string = "84:38:35:65:d1:15";
153 // iPhone 5S: static const char * device_addr_string = "54:E4:3A:26:A2:39";
154 static bd_addr_t device_addr;
155 #endif
156 
157 static btstack_packet_callback_registration_t hci_event_callback_registration;
158 
159 static uint8_t  sdp_avdtp_sink_service_buffer[150];
160 static uint8_t  sdp_avrcp_target_service_buffer[150];
161 static uint8_t  sdp_avrcp_controller_service_buffer[200];
162 static uint8_t  device_id_sdp_service_buffer[100];
163 
164 static uint16_t a2dp_cid = 0;
165 static uint8_t  a2dp_local_seid = 0;
166 
167 static uint16_t avrcp_cid = 0;
168 static uint8_t  avrcp_connected = 0;
169 static uint8_t  avrcp_subevent_value[255];
170 
171 static uint8_t media_sbc_codec_capabilities[] = {
172     0xFF,//(AVDTP_SBC_44100 << 4) | AVDTP_SBC_STEREO,
173     0xFF,//(AVDTP_SBC_BLOCK_LENGTH_16 << 4) | (AVDTP_SBC_SUBBANDS_8 << 2) | AVDTP_SBC_ALLOCATION_METHOD_LOUDNESS,
174     2, 53
175 };
176 
177 static uint8_t media_sbc_codec_configuration[4];
178 
179 static int media_initialized = 0;
180 static btstack_resample_t resample_instance;
181 
182 /* @section Main Application Setup
183  *
184  * @text The Listing MainConfiguration shows how to setup AD2P Sink and AVRCP services.
185  * Besides calling init() method for each service, you'll also need to register several packet handlers:
186  * - hci_packet_handler - handles legacy pairing, here by using fixed '0000' pin code.
187  * - a2dp_sink_packet_handler - handles events on stream connection status (established, released), the media codec configuration, and, the status of the stream itself (opened, paused, stopped).
188  * - handle_l2cap_media_data_packet - used to receive streaming data. If STORE_TO_WAV_FILE directive (check btstack_config.h) is used, the SBC decoder will be used to decode the SBC data into PCM frames. The resulting PCM frames are then processed in the SBC Decoder callback.
189  * - avrcp_packet_handler - receives connect/disconnect event.
190  * - avrcp_controller_packet_handler - receives answers for sent AVRCP commands.
191  * - avrcp_target_packet_handler - receives AVRCP commands, and registered notifications.
192  * - stdin_process - used to trigger AVRCP commands to the A2DP Source device, such are get now playing info, start, stop, volume control. Requires HAVE_BTSTACK_STDIN.
193  *
194  * @text To announce A2DP Sink and AVRCP services, you need to create corresponding
195  * SDP records and register them with the SDP service.
196  *
197  * @text Note, currently only the SBC codec is supported.
198  * If you want to store the audio data in a file, you'll need to define STORE_TO_WAV_FILE.
199  * If STORE_TO_WAV_FILE directive is defined, the SBC decoder needs to get initialized when a2dp_sink_packet_handler receives event A2DP_SUBEVENT_STREAM_STARTED.
200  * The initialization of the SBC decoder requires a callback that handles PCM data:
201  * - handle_pcm_data - handles PCM audio frames. Here, they are stored a in wav file if STORE_TO_WAV_FILE is defined, and/or played using the audio library.
202  */
203 
204 /* LISTING_START(MainConfiguration): Setup Audio Sink and AVRCP services */
205 static void hci_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
206 static void a2dp_sink_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t * event, uint16_t event_size);
207 static void handle_l2cap_media_data_packet(uint8_t seid, uint8_t *packet, uint16_t size);
208 static void avrcp_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
209 static void avrcp_controller_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
210 static void avrcp_target_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
211 #ifdef HAVE_BTSTACK_STDIN
212 static void stdin_process(char cmd);
213 #endif
214 
215 static int a2dp_and_avrcp_setup(void){
216 
217     l2cap_init();
218 
219 #ifdef ENABLE_BLE
220     // Initialize LE Security Manager. Needed for cross-transport key derivation
221     sm_init();
222 #endif
223 
224     // Initialize AVDTP Sink
225     a2dp_sink_init();
226     a2dp_sink_register_packet_handler(&a2dp_sink_packet_handler);
227     a2dp_sink_register_media_handler(&handle_l2cap_media_data_packet);
228 
229     // Create stream endpoint
230     avdtp_stream_endpoint_t * local_stream_endpoint = a2dp_sink_create_stream_endpoint(AVDTP_AUDIO,
231         AVDTP_CODEC_SBC, media_sbc_codec_capabilities, sizeof(media_sbc_codec_capabilities),
232         media_sbc_codec_configuration, sizeof(media_sbc_codec_configuration));
233     if (!local_stream_endpoint){
234         printf("A2DP Sink: not enough memory to create local stream endpoint\n");
235         return 1;
236     }
237 
238     // Store stream enpoint's SEP ID, as it is used by A2DP API to indentify the stream endpoint
239     a2dp_local_seid = avdtp_local_seid(local_stream_endpoint);
240 
241     // Initialize AVRCP service
242     avrcp_init();
243     avrcp_register_packet_handler(&avrcp_packet_handler);
244 
245     // Initialize AVRCP Controller
246     avrcp_controller_init();
247     avrcp_controller_register_packet_handler(&avrcp_controller_packet_handler);
248 
249      // Initialize AVRCP Target
250     avrcp_target_init();
251     avrcp_target_register_packet_handler(&avrcp_target_packet_handler);
252 
253     // Initialize SDP
254     sdp_init();
255 
256     // Create A2DP Sink service record and register it with SDP
257     memset(sdp_avdtp_sink_service_buffer, 0, sizeof(sdp_avdtp_sink_service_buffer));
258     a2dp_sink_create_sdp_record(sdp_avdtp_sink_service_buffer, 0x10001, AVDTP_SINK_FEATURE_MASK_HEADPHONE, NULL, NULL);
259     sdp_register_service(sdp_avdtp_sink_service_buffer);
260 
261     // Create AVRCP Controller service record and register it with SDP. We send Category 1 commands to the media player, e.g. play/pause
262     memset(sdp_avrcp_controller_service_buffer, 0, sizeof(sdp_avrcp_controller_service_buffer));
263     uint16_t controller_supported_features = AVRCP_FEATURE_MASK_CATEGORY_PLAYER_OR_RECORDER;
264 #ifdef AVRCP_BROWSING_ENABLED
265     controller_supported_features |= AVRCP_FEATURE_MASK_BROWSING;
266 #endif
267     avrcp_controller_create_sdp_record(sdp_avrcp_controller_service_buffer, 0x10002, controller_supported_features, NULL, NULL);
268     sdp_register_service(sdp_avrcp_controller_service_buffer);
269 
270     // Create AVRCP Target service record and register it with SDP. We receive Category 2 commands from the media player, e.g. volume up/down
271     memset(sdp_avrcp_target_service_buffer, 0, sizeof(sdp_avrcp_target_service_buffer));
272     uint16_t target_supported_features = AVRCP_FEATURE_MASK_CATEGORY_MONITOR_OR_AMPLIFIER;
273     avrcp_target_create_sdp_record(sdp_avrcp_target_service_buffer, 0x10003, target_supported_features, NULL, NULL);
274     sdp_register_service(sdp_avrcp_target_service_buffer);
275 
276     // Create Device ID (PnP) service record and register it with SDP
277     memset(device_id_sdp_service_buffer, 0, sizeof(device_id_sdp_service_buffer));
278     device_id_create_sdp_record(device_id_sdp_service_buffer, 0x10004, DEVICE_ID_VENDOR_ID_SOURCE_BLUETOOTH, BLUETOOTH_COMPANY_ID_BLUEKITCHEN_GMBH, 1, 1);
279     sdp_register_service(device_id_sdp_service_buffer);
280 
281     // Set local name with a template Bluetooth address, that will be automatically
282     // replaced with a actual address once it is available, i.e. when BTstack boots
283     // up and starts talking to a Bluetooth module.
284     gap_set_local_name("A2DP Sink Demo 00:00:00:00:00:00");
285 
286     // allot to show up in Bluetooth inquiry
287     gap_discoverable_control(1);
288 
289     // Service Class: Audio, Major Device Class: Audio, Minor: Loudspeaker
290     gap_set_class_of_device(0x200414);
291 
292     // allow for role switch in general and sniff mode
293     gap_set_default_link_policy_settings( LM_LINK_POLICY_ENABLE_ROLE_SWITCH | LM_LINK_POLICY_ENABLE_SNIFF_MODE );
294 
295     // allow for role switch on outgoing connections - this allows A2DP Source, e.g. smartphone, to become master when we re-connect to it
296     gap_set_allow_role_switch(true);
297 
298     // Register for HCI events
299     hci_event_callback_registration.callback = &hci_packet_handler;
300     hci_add_event_handler(&hci_event_callback_registration);
301 
302 #ifdef HAVE_POSIX_FILE_IO
303     if (!btstack_audio_sink_get_instance()){
304         printf("No audio playback.\n");
305     } else {
306         printf("Audio playback supported.\n");
307     }
308 #ifdef STORE_TO_WAV_FILE
309    printf("Audio will be stored to \'%s\' file.\n",  wav_filename);
310 #endif
311 #endif
312     return 0;
313 }
314 /* LISTING_END */
315 
316 static void playback_handler(int16_t * buffer, uint16_t num_audio_frames){
317 
318 #ifdef STORE_TO_WAV_FILE
319     int       wav_samples = num_audio_frames * NUM_CHANNELS;
320     int16_t * wav_buffer  = buffer;
321 #endif
322 
323     // called from lower-layer but guaranteed to be on main thread
324     if (sbc_frame_size == 0){
325         memset(buffer, 0, num_audio_frames * BYTES_PER_FRAME);
326         return;
327     }
328 
329     // first fill from resampled audio
330     uint32_t bytes_read;
331     btstack_ring_buffer_read(&decoded_audio_ring_buffer, (uint8_t *) buffer, num_audio_frames * BYTES_PER_FRAME, &bytes_read);
332     buffer          += bytes_read / NUM_CHANNELS;
333     num_audio_frames   -= bytes_read / BYTES_PER_FRAME;
334 
335     // then start decoding sbc frames using request_* globals
336     request_buffer = buffer;
337     request_frames = num_audio_frames;
338     while (request_frames && btstack_ring_buffer_bytes_available(&sbc_frame_ring_buffer) >= sbc_frame_size){
339         // decode frame
340         uint8_t sbc_frame[MAX_SBC_FRAME_SIZE];
341         btstack_ring_buffer_read(&sbc_frame_ring_buffer, sbc_frame, sbc_frame_size, &bytes_read);
342         btstack_sbc_decoder_process_data(&state, 0, sbc_frame, sbc_frame_size);
343     }
344 
345 #ifdef STORE_TO_WAV_FILE
346     audio_frame_count += num_audio_frames;
347     wav_writer_write_int16(wav_samples, wav_buffer);
348 #endif
349 }
350 
351 static void handle_pcm_data(int16_t * data, int num_audio_frames, int num_channels, int sample_rate, void * context){
352     UNUSED(sample_rate);
353     UNUSED(context);
354     UNUSED(num_channels);   // must be stereo == 2
355 
356     const btstack_audio_sink_t * audio_sink = btstack_audio_sink_get_instance();
357     if (!audio_sink){
358 #ifdef STORE_TO_WAV_FILE
359         audio_frame_count += num_audio_frames;
360         wav_writer_write_int16(num_audio_frames * NUM_CHANNELS, data);
361 #endif
362         return;
363     }
364 
365     // resample into request buffer - add some additional space for resampling
366     int16_t  output_buffer[(128+16) * NUM_CHANNELS]; // 16 * 8 * 2
367     uint32_t resampled_frames = btstack_resample_block(&resample_instance, data, num_audio_frames, output_buffer);
368 
369     // store data in btstack_audio buffer first
370     int frames_to_copy = btstack_min(resampled_frames, request_frames);
371     memcpy(request_buffer, output_buffer, frames_to_copy * BYTES_PER_FRAME);
372     request_frames  -= frames_to_copy;
373     request_buffer  += frames_to_copy * NUM_CHANNELS;
374 
375     // and rest in ring buffer
376     int frames_to_store = resampled_frames - frames_to_copy;
377     if (frames_to_store){
378         int status = btstack_ring_buffer_write(&decoded_audio_ring_buffer, (uint8_t *)&output_buffer[frames_to_copy * NUM_CHANNELS], frames_to_store * BYTES_PER_FRAME);
379         if (status){
380             printf("Error storing samples in PCM ring buffer!!!\n");
381         }
382     }
383 }
384 
385 static int media_processing_init(media_codec_configuration_sbc_t configuration){
386     if (media_initialized) return 0;
387 
388     btstack_sbc_decoder_init(&state, mode, handle_pcm_data, NULL);
389 
390 #ifdef STORE_TO_WAV_FILE
391     wav_writer_open(wav_filename, configuration.num_channels, configuration.sampling_frequency);
392 #endif
393 
394 #ifdef STORE_TO_SBC_FILE
395    sbc_file = fopen(sbc_filename, "wb");
396 #endif
397 
398     btstack_ring_buffer_init(&sbc_frame_ring_buffer, sbc_frame_storage, sizeof(sbc_frame_storage));
399     btstack_ring_buffer_init(&decoded_audio_ring_buffer, decoded_audio_storage, sizeof(decoded_audio_storage));
400     btstack_resample_init(&resample_instance, configuration.num_channels);
401 
402     // setup audio playback
403     const btstack_audio_sink_t * audio = btstack_audio_sink_get_instance();
404     if (audio){
405         audio->init(NUM_CHANNELS, configuration.sampling_frequency, &playback_handler);
406     }
407 
408     audio_stream_started = 0;
409     media_initialized = 1;
410     return 0;
411 }
412 
413 static void media_processing_start(void){
414     if (!media_initialized) return;
415     // setup audio playback
416     const btstack_audio_sink_t * audio = btstack_audio_sink_get_instance();
417     if (audio){
418         audio->start_stream();
419     }
420     audio_stream_started = 1;
421 }
422 
423 static void media_processing_pause(void){
424     if (!media_initialized) return;
425     // stop audio playback
426     audio_stream_started = 0;
427     const btstack_audio_sink_t * audio = btstack_audio_sink_get_instance();
428     if (audio){
429         audio->stop_stream();
430     }
431 }
432 
433 static void media_processing_close(void){
434     if (!media_initialized) return;
435     media_initialized = 0;
436     audio_stream_started = 0;
437     sbc_frame_size = 0;
438 
439 #ifdef STORE_TO_WAV_FILE
440     wav_writer_close();
441     uint32_t total_frames_nr = state.good_frames_nr + state.bad_frames_nr + state.zero_frames_nr;
442 
443     printf("WAV Writer: Decoding done. Processed %u SBC frames:\n - %d good\n - %d bad\n", total_frames_nr, state.good_frames_nr, total_frames_nr - state.good_frames_nr);
444     printf("WAV Writer: Wrote %u audio frames to wav file: %s\n", audio_frame_count, wav_filename);
445 #endif
446 
447 #ifdef STORE_TO_SBC_FILE
448     fclose(sbc_file);
449 #endif
450 
451     // stop audio playback
452     const btstack_audio_sink_t * audio = btstack_audio_sink_get_instance();
453     if (audio){
454         printf("close stream\n");
455         audio->close();
456     }
457 }
458 
459 /* @section Handle Media Data Packet
460  *
461  * @text Here the audio data, are received through the handle_l2cap_media_data_packet callback.
462  * Currently, only the SBC media codec is supported. Hence, the media data consists of the media packet header and the SBC packet.
463  * The SBC frame will be stored in a ring buffer for later processing (instead of decoding it to PCM right away which would require a much larger buffer).
464  * If the audio stream wasn't started already and there are enough SBC frames in the ring buffer, start playback.
465  */
466 
467 static int read_media_data_header(uint8_t * packet, int size, int * offset, avdtp_media_packet_header_t * media_header);
468 static int read_sbc_header(uint8_t * packet, int size, int * offset, avdtp_sbc_codec_header_t * sbc_header);
469 
470 static void handle_l2cap_media_data_packet(uint8_t seid, uint8_t *packet, uint16_t size){
471     UNUSED(seid);
472     int pos = 0;
473 
474     avdtp_media_packet_header_t media_header;
475     if (!read_media_data_header(packet, size, &pos, &media_header)) return;
476 
477     avdtp_sbc_codec_header_t sbc_header;
478     if (!read_sbc_header(packet, size, &pos, &sbc_header)) return;
479 
480 #ifdef STORE_TO_SBC_FILE
481     fwrite(packet+pos, size-pos, 1, sbc_file);
482 #endif
483 
484     const btstack_audio_sink_t * audio = btstack_audio_sink_get_instance();
485     // process data right away if there's no audio implementation active, e.g. on posix systems to store as .wav
486     if (!audio){
487         btstack_sbc_decoder_process_data(&state, 0, packet+pos, size-pos);
488         return;
489     }
490 
491     // store sbc frame size for buffer management
492     sbc_frame_size = (size-pos)/ sbc_header.num_frames;
493 
494     int status = btstack_ring_buffer_write(&sbc_frame_ring_buffer, packet+pos, size-pos);
495     if (status != ERROR_CODE_SUCCESS){
496         printf("Error storing samples in SBC ring buffer!!!\n");
497     }
498 
499     // decide on audio sync drift based on number of sbc frames in queue
500     int sbc_frames_in_buffer = btstack_ring_buffer_bytes_available(&sbc_frame_ring_buffer) / sbc_frame_size;
501     uint32_t resampling_factor;
502 
503     // nomimal factor (fixed-point 2^16) and compensation offset
504     uint32_t nomimal_factor = 0x10000;
505     uint32_t compensation   = 0x00100;
506 
507     if (sbc_frames_in_buffer < OPTIMAL_FRAMES_MIN){
508     	resampling_factor = nomimal_factor - compensation;    // stretch samples
509     } else if (sbc_frames_in_buffer <= OPTIMAL_FRAMES_MAX){
510     	resampling_factor = nomimal_factor;                   // nothing to do
511     } else {
512     	resampling_factor = nomimal_factor + compensation;    // compress samples
513     }
514 
515     btstack_resample_set_factor(&resample_instance, resampling_factor);
516 
517     // start stream if enough frames buffered
518     if (!audio_stream_started && sbc_frames_in_buffer >= OPTIMAL_FRAMES_MIN){
519         media_processing_start();
520     }
521 }
522 
523 static int read_sbc_header(uint8_t * packet, int size, int * offset, avdtp_sbc_codec_header_t * sbc_header){
524     int sbc_header_len = 12; // without crc
525     int pos = *offset;
526 
527     if (size - pos < sbc_header_len){
528         printf("Not enough data to read SBC header, expected %d, received %d\n", sbc_header_len, size-pos);
529         return 0;
530     }
531 
532     sbc_header->fragmentation = get_bit16(packet[pos], 7);
533     sbc_header->starting_packet = get_bit16(packet[pos], 6);
534     sbc_header->last_packet = get_bit16(packet[pos], 5);
535     sbc_header->num_frames = packet[pos] & 0x0f;
536     pos++;
537     *offset = pos;
538     return 1;
539 }
540 
541 static int read_media_data_header(uint8_t *packet, int size, int *offset, avdtp_media_packet_header_t *media_header){
542     int media_header_len = 12; // without crc
543     int pos = *offset;
544 
545     if (size - pos < media_header_len){
546         printf("Not enough data to read media packet header, expected %d, received %d\n", media_header_len, size-pos);
547         return 0;
548     }
549 
550     media_header->version = packet[pos] & 0x03;
551     media_header->padding = get_bit16(packet[pos],2);
552     media_header->extension = get_bit16(packet[pos],3);
553     media_header->csrc_count = (packet[pos] >> 4) & 0x0F;
554     pos++;
555 
556     media_header->marker = get_bit16(packet[pos],0);
557     media_header->payload_type  = (packet[pos] >> 1) & 0x7F;
558     pos++;
559 
560     media_header->sequence_number = big_endian_read_16(packet, pos);
561     pos+=2;
562 
563     media_header->timestamp = big_endian_read_32(packet, pos);
564     pos+=4;
565 
566     media_header->synchronization_source = big_endian_read_32(packet, pos);
567     pos+=4;
568     *offset = pos;
569     return 1;
570 }
571 
572 static void dump_sbc_configuration(media_codec_configuration_sbc_t configuration){
573     printf("    - num_channels: %d\n", configuration.num_channels);
574     printf("    - sampling_frequency: %d\n", configuration.sampling_frequency);
575     printf("    - channel_mode: %d\n", configuration.channel_mode);
576     printf("    - block_length: %d\n", configuration.block_length);
577     printf("    - subbands: %d\n", configuration.subbands);
578     printf("    - allocation_method: %d\n", configuration.allocation_method);
579     printf("    - bitpool_value [%d, %d] \n", configuration.min_bitpool_value, configuration.max_bitpool_value);
580     printf("\n");
581 }
582 
583 static void avrcp_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
584     UNUSED(channel);
585     UNUSED(size);
586     uint16_t local_cid;
587     uint8_t  status;
588     bd_addr_t address;
589 
590     if (packet_type != HCI_EVENT_PACKET) return;
591     if (hci_event_packet_get_type(packet) != HCI_EVENT_AVRCP_META) return;
592     switch (packet[2]){
593         case AVRCP_SUBEVENT_CONNECTION_ESTABLISHED: {
594             local_cid = avrcp_subevent_connection_established_get_avrcp_cid(packet);
595             status = avrcp_subevent_connection_established_get_status(packet);
596             if (status != ERROR_CODE_SUCCESS){
597                 printf("AVRCP: Connection failed: status 0x%02x\n", status);
598                 avrcp_cid = 0;
599                 return;
600             }
601 
602             avrcp_cid = local_cid;
603             avrcp_connected = 1;
604             avrcp_subevent_connection_established_get_bd_addr(packet, address);
605             printf("AVRCP: Connected to %s, cid 0x%02x\n", bd_addr_to_str(address), avrcp_cid);
606 
607             avrcp_target_support_event(avrcp_cid, AVRCP_NOTIFICATION_EVENT_VOLUME_CHANGED);
608             avrcp_target_support_event(avrcp_cid, AVRCP_NOTIFICATION_EVENT_BATT_STATUS_CHANGED);
609             avrcp_target_battery_status_changed(avrcp_cid, battery_status);
610 
611             // automatically enable notifications
612             avrcp_controller_enable_notification(avrcp_cid, AVRCP_NOTIFICATION_EVENT_PLAYBACK_STATUS_CHANGED);
613             avrcp_controller_enable_notification(avrcp_cid, AVRCP_NOTIFICATION_EVENT_NOW_PLAYING_CONTENT_CHANGED);
614             avrcp_controller_enable_notification(avrcp_cid, AVRCP_NOTIFICATION_EVENT_TRACK_CHANGED);
615             return;
616         }
617 
618         case AVRCP_SUBEVENT_CONNECTION_RELEASED:
619             printf("AVRCP: Channel released: cid 0x%02x\n", avrcp_subevent_connection_released_get_avrcp_cid(packet));
620             avrcp_cid = 0;
621             avrcp_connected = 0;
622             return;
623         default:
624             break;
625     }
626 }
627 
628 static void avrcp_controller_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
629     UNUSED(channel);
630     UNUSED(size);
631 
632     if (packet_type != HCI_EVENT_PACKET) return;
633     if (hci_event_packet_get_type(packet) != HCI_EVENT_AVRCP_META) return;
634     if (!avrcp_cid) return;
635 
636     memset(avrcp_subevent_value, 0, sizeof(avrcp_subevent_value));
637     switch (packet[2]){
638         case AVRCP_SUBEVENT_NOTIFICATION_PLAYBACK_POS_CHANGED:
639             printf("AVRCP Controller: Playback position changed, position %d ms\n", (unsigned int) avrcp_subevent_notification_playback_pos_changed_get_playback_position_ms(packet));
640             break;
641         case AVRCP_SUBEVENT_NOTIFICATION_PLAYBACK_STATUS_CHANGED:
642             printf("AVRCP Controller: Playback status changed %s\n", avrcp_play_status2str(avrcp_subevent_notification_playback_status_changed_get_play_status(packet)));
643             return;
644         case AVRCP_SUBEVENT_NOTIFICATION_NOW_PLAYING_CONTENT_CHANGED:
645             printf("AVRCP Controller: Playing content changed\n");
646             return;
647         case AVRCP_SUBEVENT_NOTIFICATION_TRACK_CHANGED:
648             printf("AVRCP Controller: Track changed\n");
649             return;
650         case AVRCP_SUBEVENT_NOTIFICATION_AVAILABLE_PLAYERS_CHANGED:
651             printf("AVRCP Controller: Changed\n");
652             return;
653         case AVRCP_SUBEVENT_SHUFFLE_AND_REPEAT_MODE:{
654             uint8_t shuffle_mode = avrcp_subevent_shuffle_and_repeat_mode_get_shuffle_mode(packet);
655             uint8_t repeat_mode  = avrcp_subevent_shuffle_and_repeat_mode_get_repeat_mode(packet);
656             printf("AVRCP Controller: %s, %s\n", avrcp_shuffle2str(shuffle_mode), avrcp_repeat2str(repeat_mode));
657             break;
658         }
659         case AVRCP_SUBEVENT_NOW_PLAYING_TRACK_INFO:
660             printf("AVRCP Controller:     Track: %d\n", avrcp_subevent_now_playing_track_info_get_track(packet));
661             break;
662 
663         case AVRCP_SUBEVENT_NOW_PLAYING_TOTAL_TRACKS_INFO:
664             printf("AVRCP Controller:     Total Tracks: %d\n", avrcp_subevent_now_playing_total_tracks_info_get_total_tracks(packet));
665             break;
666 
667         case AVRCP_SUBEVENT_NOW_PLAYING_TITLE_INFO:
668             if (avrcp_subevent_now_playing_title_info_get_value_len(packet) > 0){
669                 memcpy(avrcp_subevent_value, avrcp_subevent_now_playing_title_info_get_value(packet), avrcp_subevent_now_playing_title_info_get_value_len(packet));
670                 printf("AVRCP Controller:     Title: %s\n", avrcp_subevent_value);
671             }
672             break;
673 
674         case AVRCP_SUBEVENT_NOW_PLAYING_ARTIST_INFO:
675             if (avrcp_subevent_now_playing_artist_info_get_value_len(packet) > 0){
676                 memcpy(avrcp_subevent_value, avrcp_subevent_now_playing_artist_info_get_value(packet), avrcp_subevent_now_playing_artist_info_get_value_len(packet));
677                 printf("AVRCP Controller:     Artist: %s\n", avrcp_subevent_value);
678             }
679             break;
680 
681         case AVRCP_SUBEVENT_NOW_PLAYING_ALBUM_INFO:
682             if (avrcp_subevent_now_playing_album_info_get_value_len(packet) > 0){
683                 memcpy(avrcp_subevent_value, avrcp_subevent_now_playing_album_info_get_value(packet), avrcp_subevent_now_playing_album_info_get_value_len(packet));
684                 printf("AVRCP Controller:     Album: %s\n", avrcp_subevent_value);
685             }
686             break;
687 
688         case AVRCP_SUBEVENT_NOW_PLAYING_GENRE_INFO:
689             if (avrcp_subevent_now_playing_genre_info_get_value_len(packet) > 0){
690                 memcpy(avrcp_subevent_value, avrcp_subevent_now_playing_genre_info_get_value(packet), avrcp_subevent_now_playing_genre_info_get_value_len(packet));
691                 printf("AVRCP Controller:     Genre: %s\n", avrcp_subevent_value);
692             }
693             break;
694 
695         case AVRCP_SUBEVENT_PLAY_STATUS:
696             printf("AVRCP Controller: Song length %"PRIu32" ms, Song position %"PRIu32" ms, Play status %s\n",
697                 avrcp_subevent_play_status_get_song_length(packet),
698                 avrcp_subevent_play_status_get_song_position(packet),
699                 avrcp_play_status2str(avrcp_subevent_play_status_get_play_status(packet)));
700             break;
701 
702         case AVRCP_SUBEVENT_OPERATION_COMPLETE:
703             printf("AVRCP Controller: %s complete\n", avrcp_operation2str(avrcp_subevent_operation_complete_get_operation_id(packet)));
704             break;
705 
706         case AVRCP_SUBEVENT_OPERATION_START:
707             printf("AVRCP Controller: %s start\n", avrcp_operation2str(avrcp_subevent_operation_start_get_operation_id(packet)));
708             break;
709 
710         case AVRCP_SUBEVENT_NOTIFICATION_EVENT_TRACK_REACHED_END:
711             printf("AVRCP Controller: Track reached end\n");
712             break;
713 
714         case AVRCP_SUBEVENT_PLAYER_APPLICATION_VALUE_RESPONSE:
715             printf("AVRCP Controller: Set Player App Value %s\n", avrcp_ctype2str(avrcp_subevent_player_application_value_response_get_command_type(packet)));
716             break;
717 
718         default:
719             break;
720     }
721 }
722 
723 static void avrcp_volume_changed(uint8_t volume){
724     const btstack_audio_sink_t * audio = btstack_audio_sink_get_instance();
725     if (audio){
726         audio->set_volume(volume);
727     }
728 }
729 
730 static void avrcp_target_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
731     UNUSED(channel);
732     UNUSED(size);
733 
734     if (packet_type != HCI_EVENT_PACKET) return;
735     if (hci_event_packet_get_type(packet) != HCI_EVENT_AVRCP_META) return;
736 
737     uint8_t volume;
738     char const * button_state;
739     avrcp_operation_id_t operation_id;
740 
741     switch (packet[2]){
742         case AVRCP_SUBEVENT_NOTIFICATION_VOLUME_CHANGED:
743             volume = avrcp_subevent_notification_volume_changed_get_absolute_volume(packet);
744             volume_percentage = volume * 100 / 127;
745             printf("AVRCP Target    : Volume set to %d%% (%d)\n", volume_percentage, volume);
746             avrcp_volume_changed(volume);
747             break;
748 
749         case AVRCP_SUBEVENT_OPERATION:
750             operation_id = avrcp_subevent_operation_get_operation_id(packet);
751             button_state = avrcp_subevent_operation_get_button_pressed(packet) > 0 ? "PRESS" : "RELEASE";
752             switch (operation_id){
753                 case AVRCP_OPERATION_ID_VOLUME_UP:
754                     printf("AVRCP Target    : VOLUME UP (%s)\n", button_state);
755                     break;
756                 case AVRCP_OPERATION_ID_VOLUME_DOWN:
757                     printf("AVRCP Target    : VOLUME UP (%s)\n", button_state);
758                     break;
759                 default:
760                     return;
761             }
762             break;
763         default:
764             printf("AVRCP Target    : Event 0x%02x is not parsed\n", packet[2]);
765             break;
766     }
767 }
768 
769 static void hci_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
770     UNUSED(channel);
771     UNUSED(size);
772     if (packet_type != HCI_EVENT_PACKET) return;
773     if (hci_event_packet_get_type(packet) == HCI_EVENT_PIN_CODE_REQUEST) {
774         bd_addr_t address;
775         printf("Pin code request - using '0000'\n");
776         hci_event_pin_code_request_get_bd_addr(packet, address);
777         gap_pin_code_response(address, "0000");
778     }
779 }
780 
781 static void a2dp_sink_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
782     UNUSED(channel);
783     UNUSED(size);
784     bd_addr_t address;
785     uint8_t status;
786 
787     uint8_t allocation_method;
788 
789     if (packet_type != HCI_EVENT_PACKET) return;
790     if (hci_event_packet_get_type(packet) != HCI_EVENT_A2DP_META) return;
791 
792     switch (packet[2]){
793         case A2DP_SUBEVENT_SIGNALING_MEDIA_CODEC_OTHER_CONFIGURATION:
794             printf("A2DP  Sink      : Received non SBC codec - not implemented\n");
795             break;
796         case A2DP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CONFIGURATION:{
797             printf("A2DP  Sink      : Received SBC codec configuration\n");
798             sbc_configuration.reconfigure = a2dp_subevent_signaling_media_codec_sbc_configuration_get_reconfigure(packet);
799             sbc_configuration.num_channels = a2dp_subevent_signaling_media_codec_sbc_configuration_get_num_channels(packet);
800             sbc_configuration.sampling_frequency = a2dp_subevent_signaling_media_codec_sbc_configuration_get_sampling_frequency(packet);
801             sbc_configuration.block_length = a2dp_subevent_signaling_media_codec_sbc_configuration_get_block_length(packet);
802             sbc_configuration.subbands = a2dp_subevent_signaling_media_codec_sbc_configuration_get_subbands(packet);
803             sbc_configuration.min_bitpool_value = a2dp_subevent_signaling_media_codec_sbc_configuration_get_min_bitpool_value(packet);
804             sbc_configuration.max_bitpool_value = a2dp_subevent_signaling_media_codec_sbc_configuration_get_max_bitpool_value(packet);
805 
806             allocation_method = a2dp_subevent_signaling_media_codec_sbc_configuration_get_allocation_method(packet);
807 
808             // Adapt Bluetooth spec definition to SBC Encoder expected input
809             sbc_configuration.allocation_method = (btstack_sbc_allocation_method_t)(allocation_method - 1);
810 
811             switch (a2dp_subevent_signaling_media_codec_sbc_configuration_get_channel_mode(packet)){
812                 case AVDTP_CHANNEL_MODE_JOINT_STEREO:
813                     sbc_configuration.channel_mode = SBC_CHANNEL_MODE_JOINT_STEREO;
814                     break;
815                 case AVDTP_CHANNEL_MODE_STEREO:
816                     sbc_configuration.channel_mode = SBC_CHANNEL_MODE_STEREO;
817                     break;
818                 case AVDTP_CHANNEL_MODE_DUAL_CHANNEL:
819                     sbc_configuration.channel_mode = SBC_CHANNEL_MODE_DUAL_CHANNEL;
820                     break;
821                 case AVDTP_CHANNEL_MODE_MONO:
822                     sbc_configuration.channel_mode = SBC_CHANNEL_MODE_MONO;
823                     break;
824                 default:
825                     btstack_assert(false);
826                     break;
827             }
828             dump_sbc_configuration(sbc_configuration);
829 
830             if (sbc_configuration.reconfigure){
831                 media_processing_close();
832             }
833             // prepare media processing
834             media_processing_init(sbc_configuration);
835             break;
836         }
837         case A2DP_SUBEVENT_STREAM_ESTABLISHED:
838             a2dp_subevent_stream_established_get_bd_addr(packet, address);
839             status = a2dp_subevent_stream_established_get_status(packet);
840             if (status != ERROR_CODE_SUCCESS){
841                 printf("A2DP  Sink      : Streaming connection failed, status 0x%02x\n", status);
842                 break;
843             }
844 
845             a2dp_cid = a2dp_subevent_stream_established_get_a2dp_cid(packet);
846             printf("A2DP  Sink      : Streaming connection is established, address %s, cid 0x%02X, local seid %d\n", bd_addr_to_str(address), a2dp_cid, a2dp_local_seid);
847 #ifdef HAVE_BTSTACK_STDIN
848             // use address for outgoing connections
849             memcpy(device_addr, address, 6);
850 #endif
851             break;
852 
853 #ifdef ENABLE_AVDTP_ACCEPTOR_EXPLICIT_START_STREAM_CONFIRMATION
854         case A2DP_SUBEVENT_START_STREAM_REQUESTED:
855             printf("A2DP  Sink      : Explicit Accept to start stream, local_seid 0x%02x\n", a2dp_subevent_start_stream_requested_get_local_seid(packet));
856             a2dp_sink_start_stream_accept(a2dp_cid, a2dp_local_seid);
857             break;
858 #endif
859         case A2DP_SUBEVENT_STREAM_STARTED:
860             printf("A2DP  Sink      : Stream started\n");
861             // audio stream is started when buffer reaches minimal level
862             break;
863 
864         case A2DP_SUBEVENT_STREAM_SUSPENDED:
865             printf("A2DP  Sink      : Stream paused\n");
866             media_processing_pause();
867             break;
868 
869         case A2DP_SUBEVENT_STREAM_RELEASED:
870             printf("A2DP  Sink      : Stream released\n");
871             media_processing_close();
872             break;
873 
874         case A2DP_SUBEVENT_SIGNALING_CONNECTION_RELEASED:
875             printf("A2DP  Sink      : Signaling connection released\n");
876             media_processing_close();
877             break;
878 
879         default:
880             break;
881     }
882 }
883 
884 #ifdef HAVE_BTSTACK_STDIN
885 static void show_usage(void){
886     bd_addr_t      iut_address;
887     gap_local_bd_addr(iut_address);
888     printf("\n--- Bluetooth AVDTP Sink/AVRCP Connection Test Console %s ---\n", bd_addr_to_str(iut_address));
889     printf("b      - AVDTP Sink create  connection to addr %s\n", bd_addr_to_str(device_addr));
890     printf("B      - AVDTP Sink disconnect\n");
891     printf("c      - AVRCP create connection to addr %s\n", bd_addr_to_str(device_addr));
892     printf("C      - AVRCP disconnect\n");
893 
894     printf("w - delay report\n");
895 
896     printf("\n--- Bluetooth AVRCP Commands %s ---\n", bd_addr_to_str(iut_address));
897     printf("O - get play status\n");
898     printf("j - get now playing info\n");
899     printf("k - play\n");
900     printf("K - stop\n");
901     printf("L - pause\n");
902     printf("u - start fast forward\n");
903     printf("U - stop  fast forward\n");
904     printf("n - start rewind\n");
905     printf("N - stop rewind\n");
906     printf("i - forward\n");
907     printf("I - backward\n");
908     printf("M - mute\n");
909     printf("r - skip\n");
910     printf("q - query repeat and shuffle mode\n");
911     printf("v - repeat single track\n");
912     printf("x - repeat all tracks\n");
913     printf("X - disable repeat mode\n");
914     printf("z - shuffle all tracks\n");
915     printf("Z - disable shuffle mode\n");
916 
917     printf("a/A - register/deregister TRACK_CHANGED\n");
918     printf("R/P - register/deregister PLAYBACK_POS_CHANGED\n");
919 
920     printf("s/S - send/release long button press REWIND\n");
921 
922     printf("\n--- Volume and Battery Control ---\n");
923     printf("t - volume up   for 10 percent\n");
924     printf("T - volume down for 10 percent\n");
925     printf("V - toggle Battery status from AVRCP_BATTERY_STATUS_NORMAL to AVRCP_BATTERY_STATUS_FULL_CHARGE\n");
926     printf("---\n");
927 }
928 #endif
929 
930 #ifdef HAVE_BTSTACK_STDIN
931 static void stdin_process(char cmd){
932     uint8_t status = ERROR_CODE_SUCCESS;
933     uint8_t volume;
934     avrcp_battery_status_t old_battery_status;
935 
936     switch (cmd){
937         case 'b':
938             status = a2dp_sink_establish_stream(device_addr, a2dp_local_seid, &a2dp_cid);
939             printf(" - Create AVDTP connection to addr %s, and local seid %d, expected cid 0x%02x.\n", bd_addr_to_str(device_addr), a2dp_local_seid, a2dp_cid);
940             break;
941         case 'B':
942             printf(" - AVDTP disconnect from addr %s.\n", bd_addr_to_str(device_addr));
943             a2dp_sink_disconnect(a2dp_cid);
944             break;
945         case 'c':
946             printf(" - Create AVRCP connection to addr %s.\n", bd_addr_to_str(device_addr));
947             status = avrcp_connect(device_addr, &avrcp_cid);
948             break;
949         case 'C':
950             printf(" - AVRCP disconnect from addr %s.\n", bd_addr_to_str(device_addr));
951             status = avrcp_disconnect(avrcp_cid);
952             break;
953 
954         case '\n':
955         case '\r':
956             break;
957         case 'w':
958             printf("Send delay report\n");
959             avdtp_sink_delay_report(a2dp_cid, a2dp_local_seid, 100);
960             break;
961         // Volume Control
962         case 't':
963             volume_percentage = volume_percentage <= 90 ? volume_percentage + 10 : 100;
964             volume = volume_percentage * 127 / 100;
965             printf(" - volume up   for 10 percent, %d%% (%d) \n", volume_percentage, volume);
966             status = avrcp_target_volume_changed(avrcp_cid, volume);
967             avrcp_volume_changed(volume);
968             break;
969         case 'T':
970             volume_percentage = volume_percentage >= 10 ? volume_percentage - 10 : 0;
971             volume = volume_percentage * 127 / 100;
972             printf(" - volume down for 10 percent, %d%% (%d) \n", volume_percentage, volume);
973             status = avrcp_target_volume_changed(avrcp_cid, volume);
974             avrcp_volume_changed(volume);
975             break;
976         case 'V':
977             old_battery_status = battery_status;
978 
979             if (battery_status < AVRCP_BATTERY_STATUS_FULL_CHARGE){
980                 battery_status = (avrcp_battery_status_t)((uint8_t) battery_status + 1);
981             } else {
982                 battery_status = AVRCP_BATTERY_STATUS_NORMAL;
983             }
984             printf(" - toggle battery value, old %d, new %d\n", old_battery_status, battery_status);
985             status = avrcp_target_battery_status_changed(avrcp_cid, battery_status);
986             break;
987         case 'O':
988             printf(" - get play status\n");
989             status = avrcp_controller_get_play_status(avrcp_cid);
990             break;
991         case 'j':
992             printf(" - get now playing info\n");
993             status = avrcp_controller_get_now_playing_info(avrcp_cid);
994             break;
995         case 'k':
996             printf(" - play\n");
997             status = avrcp_controller_play(avrcp_cid);
998             break;
999         case 'K':
1000             printf(" - stop\n");
1001             status = avrcp_controller_stop(avrcp_cid);
1002             break;
1003         case 'L':
1004             printf(" - pause\n");
1005             status = avrcp_controller_pause(avrcp_cid);
1006             break;
1007         case 'u':
1008             printf(" - start fast forward\n");
1009             status = avrcp_controller_press_and_hold_fast_forward(avrcp_cid);
1010             break;
1011         case 'U':
1012             printf(" - stop fast forward\n");
1013             status = avrcp_controller_release_press_and_hold_cmd(avrcp_cid);
1014             break;
1015         case 'n':
1016             printf(" - start rewind\n");
1017             status = avrcp_controller_press_and_hold_rewind(avrcp_cid);
1018             break;
1019         case 'N':
1020             printf(" - stop rewind\n");
1021             status = avrcp_controller_release_press_and_hold_cmd(avrcp_cid);
1022             break;
1023         case 'i':
1024             printf(" - forward\n");
1025             status = avrcp_controller_forward(avrcp_cid);
1026             break;
1027         case 'I':
1028             printf(" - backward\n");
1029             status = avrcp_controller_backward(avrcp_cid);
1030             break;
1031         case 'M':
1032             printf(" - mute\n");
1033             status = avrcp_controller_mute(avrcp_cid);
1034             break;
1035         case 'r':
1036             printf(" - skip\n");
1037             status = avrcp_controller_skip(avrcp_cid);
1038             break;
1039         case 'q':
1040             printf(" - query repeat and shuffle mode\n");
1041             status = avrcp_controller_query_shuffle_and_repeat_modes(avrcp_cid);
1042             break;
1043         case 'v':
1044             printf(" - repeat single track\n");
1045             status = avrcp_controller_set_repeat_mode(avrcp_cid, AVRCP_REPEAT_MODE_SINGLE_TRACK);
1046             break;
1047         case 'x':
1048             printf(" - repeat all tracks\n");
1049             status = avrcp_controller_set_repeat_mode(avrcp_cid, AVRCP_REPEAT_MODE_ALL_TRACKS);
1050             break;
1051         case 'X':
1052             printf(" - disable repeat mode\n");
1053             status = avrcp_controller_set_repeat_mode(avrcp_cid, AVRCP_REPEAT_MODE_OFF);
1054             break;
1055         case 'z':
1056             printf(" - shuffle all tracks\n");
1057             status = avrcp_controller_set_shuffle_mode(avrcp_cid, AVRCP_SHUFFLE_MODE_ALL_TRACKS);
1058             break;
1059         case 'Z':
1060             printf(" - disable shuffle mode\n");
1061             status = avrcp_controller_set_shuffle_mode(avrcp_cid, AVRCP_SHUFFLE_MODE_OFF);
1062             break;
1063         case 'a':
1064             printf("AVRCP: enable notification TRACK_CHANGED\n");
1065             avrcp_controller_enable_notification(avrcp_cid, AVRCP_NOTIFICATION_EVENT_TRACK_CHANGED);
1066             break;
1067         case 'A':
1068             printf("AVRCP: disable notification TRACK_CHANGED\n");
1069             avrcp_controller_disable_notification(avrcp_cid, AVRCP_NOTIFICATION_EVENT_TRACK_CHANGED);
1070             break;
1071         case 'R':
1072             printf("AVRCP: enable notification PLAYBACK_POS_CHANGED\n");
1073             avrcp_controller_enable_notification(avrcp_cid, AVRCP_NOTIFICATION_EVENT_PLAYBACK_POS_CHANGED);
1074             break;
1075         case 'P':
1076             printf("AVRCP: disable notification PLAYBACK_POS_CHANGED\n");
1077             avrcp_controller_disable_notification(avrcp_cid, AVRCP_NOTIFICATION_EVENT_PLAYBACK_POS_CHANGED);
1078             break;
1079          case 's':
1080             printf("AVRCP: send long button press REWIND\n");
1081             avrcp_controller_start_press_and_hold_cmd(avrcp_cid, AVRCP_OPERATION_ID_REWIND);
1082             break;
1083         case 'S':
1084             printf("AVRCP: release long button press REWIND\n");
1085             avrcp_controller_release_press_and_hold_cmd(avrcp_cid);
1086             break;
1087         default:
1088             show_usage();
1089             return;
1090     }
1091     if (status != ERROR_CODE_SUCCESS){
1092         printf("Could not perform command, status 0x%02x\n", status);
1093     }
1094 }
1095 #endif
1096 
1097 int btstack_main(int argc, const char * argv[]);
1098 int btstack_main(int argc, const char * argv[]){
1099     UNUSED(argc);
1100     (void)argv;
1101 
1102     a2dp_and_avrcp_setup();
1103 
1104 #ifdef HAVE_BTSTACK_STDIN
1105     // parse human readable Bluetooth address
1106     sscanf_bd_addr(device_addr_string, device_addr);
1107     btstack_stdin_setup(stdin_process);
1108 #endif
1109 
1110     // turn on!
1111     printf("Starting BTstack ...\n");
1112     hci_power_control(HCI_POWER_ON);
1113     return 0;
1114 }
1115 /* EXAMPLE_END */
1116