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_browsing_client.c" 39 40 /* 41 * avrcp_browsing_client.c 42 */ 43 44 // ***************************************************************************** 45 /* EXAMPLE_START(avrcp_browsing_client): Browse media players and media information on a remote device. 46 * 47 * @text This example demonstrates how to use the AVRCP Controller Browsing service to 48 * browse madia players and media information on a remote AVRCP Source device. 49 * 50 * @test To test with a remote device, e.g. a mobile phone, 51 * pair from the remote device with the demo, then use the UI for browsing (tap 52 * SPACE on the console to show the available AVRCP commands). 53 * 54 */ 55 // ***************************************************************************** 56 57 #include <stdint.h> 58 #include <inttypes.h> 59 #include <stdio.h> 60 #include <stdlib.h> 61 #include <string.h> 62 63 #include "btstack.h" 64 65 #ifdef HAVE_BTSTACK_STDIN 66 #include "btstack_stdin.h" 67 #endif 68 69 #define AVRCP_BROWSING_MAX_PLAYERS 10 70 #define AVRCP_BROWSING_MAX_FOLDERS 10 71 #define AVRCP_BROWSING_MAX_FOLDER_NAME_LEN 30 72 73 #ifdef HAVE_BTSTACK_STDIN 74 // mac 2011: static bd_addr_t remote = {0x04, 0x0C, 0xCE, 0xE4, 0x85, 0xD3}; 75 // pts: static bd_addr_t remote = {0x00, 0x1B, 0xDC, 0x08, 0x0A, 0xA5}; 76 // mac 2013: 77 // static const char * device_addr_string = "84:38:35:65:d1:15"; 78 // iPhone 5S: static const char * device_addr_string = "54:E4:3A:26:A2:39"; 79 // phone 2013: 80 // static const char * device_addr_string = "B0:34:95:CB:97:C4"; 81 82 static const char * device_addr_string = "B0:34:95:CB:97:C4"; 83 84 static bd_addr_t device_addr; 85 #endif 86 87 static uint16_t avrcp_cid = 0; 88 static uint8_t avrcp_connected = 0; 89 90 static uint16_t browsing_cid = 0; 91 static uint8_t avrcp_browsing_connected = 0; 92 static uint8_t sdp_avrcp_browsing_controller_service_buffer[200]; 93 94 static uint8_t browsing_query_active = 0; 95 static avrcp_media_item_context_t media_item_context; 96 97 typedef struct { 98 uint16_t charset; 99 uint8_t depth; 100 uint16_t name_len; 101 char name[AVRCP_BROWSING_MAX_FOLDER_NAME_LEN]; 102 } avrcp_browsing_root_folder_t; 103 104 typedef struct { 105 uint8_t uid[8]; 106 uint16_t name_len; 107 char name[AVRCP_BROWSING_MAX_FOLDER_NAME_LEN]; 108 } avrcp_browsing_folders_t; 109 110 static uint8_t parent_folder_set = 0; 111 static uint8_t parent_folder_uid[8]; 112 static char parent_folder_name[AVRCP_BROWSING_MAX_FOLDER_NAME_LEN]; 113 static avrcp_browsing_folders_t folders[AVRCP_BROWSING_MAX_FOLDERS]; 114 static int folder_index = -1; 115 static uint16_t players[AVRCP_BROWSING_MAX_PLAYERS]; 116 static int player_index = -1; 117 static uint16_t browsing_uid_counter = 0; 118 119 static btstack_packet_callback_registration_t hci_event_callback_registration; 120 121 static uint8_t ertm_buffer[10000]; 122 static l2cap_ertm_config_t ertm_config = { 123 1, // ertm mandatory 124 2, // max transmit, some tests require > 1 125 2000, 126 12000, 127 144, // l2cap ertm mtu 128 4, 129 4, 130 0, // No FCS 131 }; 132 133 134 static inline int next_index(int * index, int max_value){ 135 if ((*index) < max_value){ 136 (*index)++; 137 } else { 138 (*index) = 0; 139 } 140 return (*index); 141 } 142 143 static int next_folder_index(){ 144 return next_index(&folder_index, AVRCP_BROWSING_MAX_FOLDERS); 145 } 146 147 static int next_player_index(){ 148 return next_index(&player_index, AVRCP_BROWSING_MAX_PLAYERS); 149 } 150 151 152 /* @section Main Application Setup 153 * 154 * @text The Listing MainConfiguration shows how to setup AVRCP Controller Browsing service. 155 * To announce AVRCP Controller Browsing service, you need to create corresponding 156 * SDP record and register it with the SDP service. 157 * You'll also need to register several packet handlers: 158 * - stdin_process callback - used to trigger AVRCP commands, such are get media players, playlists, albums, etc. Requires HAVE_BTSTACK_STDIN. 159 * - avrcp_browsing_controller_packet_handler - used to receive answers for AVRCP commands. 160 * 161 */ 162 163 /* LISTING_START(MainConfiguration): Setup Audio Sink and AVRCP Controller services */ 164 static void avrcp_browsing_controller_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size); 165 #ifdef HAVE_BTSTACK_STDIN 166 static void stdin_process(char cmd); 167 #endif 168 169 #define BROWSING_ENABLED 1 170 171 int btstack_main(int argc, const char * argv[]); 172 int btstack_main(int argc, const char * argv[]){ 173 (void)argc; 174 (void)argv; 175 176 // Initialize L2CAP. 177 l2cap_init(); 178 179 // Initialize AVRCP Controller. 180 avrcp_controller_init(); 181 182 // Initialize AVRCP Browsing Controller, HCI events will be sent to the AVRCP Controller callback. 183 avrcp_browsing_controller_init(); 184 // // Register AVRCP for HCI events. 185 avrcp_browsing_controller_register_packet_handler(&avrcp_browsing_controller_packet_handler); 186 187 // Initialize SDP. 188 sdp_init(); 189 190 // Create AVRCP service record and register it with SDP. 191 memset(sdp_avrcp_browsing_controller_service_buffer, 0, sizeof(sdp_avrcp_browsing_controller_service_buffer)); 192 avrcp_controller_create_sdp_record(sdp_avrcp_browsing_controller_service_buffer, 0x10001, BROWSING_ENABLED, 1, NULL, NULL); 193 sdp_register_service(sdp_avrcp_browsing_controller_service_buffer); 194 195 // Set local name with a template Bluetooth address, that will be automatically 196 // replaced with a actual address once it is available, i.e. when BTstack boots 197 // up and starts talking to a Bluetooth module. 198 gap_set_local_name("AVRCP Browsing Client 00:00:00:00:00:00"); 199 gap_discoverable_control(1); 200 gap_set_class_of_device(0x200408); 201 202 // Register for HCI events. 203 hci_event_callback_registration.callback = &avrcp_browsing_controller_packet_handler; 204 hci_add_event_handler(&hci_event_callback_registration); 205 206 // Register for AVRCP events. 207 avrcp_controller_register_packet_handler(&avrcp_browsing_controller_packet_handler); 208 209 210 #ifdef HAVE_BTSTACK_STDIN 211 // Parse human readable Bluetooth address. 212 sscanf_bd_addr(device_addr_string, device_addr); 213 btstack_stdin_setup(stdin_process); 214 #endif 215 printf("Starting BTstack ...\n"); 216 hci_power_control(HCI_POWER_ON); 217 return 0; 218 } 219 /* LISTING_END */ 220 221 static void avrcp_browsing_controller_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 222 UNUSED(channel); 223 int pos; 224 225 switch(packet_type){ 226 case AVRCP_BROWSING_DATA_PACKET: 227 pos = 0; 228 browsing_query_active = 1; 229 avrcp_browsing_item_type_t data_type = (avrcp_browsing_item_type_t)packet[pos++]; 230 pos += 2; // length 231 232 switch (data_type){ 233 case AVRCP_BROWSING_MEDIA_ROOT_FOLDER:{ 234 avrcp_browsing_root_folder_t root_folder; 235 root_folder.charset = big_endian_read_16(packet, pos); 236 pos += 2; 237 root_folder.depth = packet[pos++]; 238 root_folder.name_len = big_endian_read_16(packet, pos); 239 pos += 2; 240 241 memset(root_folder.name, 0, AVRCP_BROWSING_MAX_FOLDER_NAME_LEN); 242 root_folder.name_len = btstack_min(big_endian_read_16(packet, pos), AVRCP_BROWSING_MAX_FOLDER_NAME_LEN - 1); 243 memcpy(root_folder.name, packet+pos, root_folder.name_len); 244 printf("Found root folder: name %s, depth %d \n", (char *)root_folder.name, root_folder.depth); 245 break; 246 } 247 case AVRCP_BROWSING_MEDIA_PLAYER_ITEM:{ 248 printf("Received media player: "); 249 uint16_t player_id = big_endian_read_16(packet, pos); 250 pos += 2; 251 avrcp_browsing_media_player_major_type_t major_type = packet[pos++]; 252 avrcp_browsing_media_player_subtype_t subtype = big_endian_read_32(packet, pos); 253 pos += 4; 254 uint8_t status = packet[pos++]; 255 uint8_t feature_bitmask[16]; 256 memcpy(feature_bitmask, packet, 16); 257 pos += 16; 258 printf("player ID 0x%04x, major_type %d, subtype %d, status %d\n", player_id, major_type, subtype, status); 259 players[next_player_index()] = player_id; 260 break; 261 } 262 case AVRCP_BROWSING_FOLDER_ITEM:{ 263 int index = next_folder_index(); 264 // printf("Found folder [%d]: ", index); 265 memcpy(folders[index].uid, packet+pos, 8); 266 uint32_t folder_uid_high = big_endian_read_32(packet, pos); 267 pos += 4; 268 uint32_t folder_uid_low = big_endian_read_32(packet, pos); 269 pos += 4; 270 avrcp_browsing_folder_type_t folder_type = packet[pos++]; 271 uint8_t is_playable = packet[pos++]; 272 uint16_t charset = big_endian_read_16(packet, pos); 273 pos += 2; 274 uint16_t displayable_name_length = big_endian_read_16(packet, pos); 275 pos += 2; 276 277 char value[AVRCP_BROWSING_MAX_FOLDER_NAME_LEN]; 278 279 memset(value, 0, AVRCP_BROWSING_MAX_FOLDER_NAME_LEN); 280 uint16_t value_len = btstack_min(displayable_name_length, AVRCP_BROWSING_MAX_FOLDER_NAME_LEN - 1); 281 memcpy(value, packet+pos, value_len); 282 283 printf("UID 0x%08" PRIx32 "%08" PRIx32 ", type 0x%02x, is_playable %d, charset 0x%02x, name %s\n", 284 folder_uid_high, folder_uid_low, folder_type, is_playable, charset, value); 285 memcpy(folders[index].name, value, value_len); 286 folders[index].name_len = value_len; 287 break; 288 } 289 case AVRCP_BROWSING_MEDIA_ELEMENT_ITEM:{ 290 printf("Found media: "); 291 292 uint32_t media_uid_high = big_endian_read_32(packet, pos); 293 pos += 4; 294 uint32_t media_uid_low = big_endian_read_32(packet, pos+4); 295 pos += 4; 296 avrcp_browsing_media_type_t media_type = packet[pos++]; 297 uint16_t charset = big_endian_read_16(packet, pos); 298 pos += 2; 299 uint16_t displayable_name_length = big_endian_read_16(packet, pos); 300 pos += 2; 301 pos += displayable_name_length; 302 printf("Media UID: 0x%08" PRIx32 "%08" PRIx32 ", media_type 0x%02x, charset 0x%02x, displayable_name_length %d\n", media_uid_high, media_uid_low, media_type, charset, displayable_name_length); 303 304 uint8_t num_attributes = packet[pos++]; 305 printf("Num media attributes %d\n", num_attributes); 306 307 for (avrcp_media_item_iterator_init(&media_item_context, size-pos, packet+pos); avrcp_media_item_iterator_has_more(&media_item_context); avrcp_media_item_iterator_next(&media_item_context)){ 308 uint32_t attr_id = avrcp_media_item_iterator_get_attr_id(&media_item_context); 309 uint16_t attr_charset = avrcp_media_item_iterator_get_attr_charset(&media_item_context); 310 uint16_t attr_value_length = avrcp_media_item_iterator_get_attr_value_len(&media_item_context); 311 const uint8_t * attr_value = avrcp_media_item_iterator_get_attr_value(&media_item_context); 312 313 printf("Attr ID 0x%08" PRIx32 ", charset %d, attr_value_length %d, value %s", attr_id, attr_charset, attr_value_length, attr_value); 314 } 315 break; 316 } 317 318 default: 319 log_error("AVRCP browsing: unknown browsable item type 0%02x", data_type); 320 break; 321 } 322 break; 323 case HCI_EVENT_PACKET: 324 if (hci_event_packet_get_type(packet) != HCI_EVENT_AVRCP_META) return; 325 uint16_t local_cid; 326 uint8_t status = 0xFF; 327 bd_addr_t address; 328 329 if (packet[0] != HCI_EVENT_AVRCP_META) break; 330 switch (packet[2]){ 331 case AVRCP_SUBEVENT_CONNECTION_ESTABLISHED: { 332 local_cid = avrcp_subevent_connection_established_get_avrcp_cid(packet); 333 printf("AVRCP_SUBEVENT_CONNECTION_ESTABLISHED cid 0x%02x\n", local_cid); 334 335 if (avrcp_cid != 0 && avrcp_cid != local_cid) { 336 printf("AVRCP Controller connection failed, expected 0x%02X l2cap cid, received 0x%02X\n", avrcp_cid, local_cid); 337 return; 338 } 339 340 status = avrcp_subevent_connection_established_get_status(packet); 341 if (status != ERROR_CODE_SUCCESS){ 342 printf("AVRCP Controller connection failed: status 0x%02x\n", status); 343 avrcp_cid = 0; 344 return; 345 } 346 347 avrcp_cid = local_cid; 348 avrcp_connected = 1; 349 avrcp_subevent_connection_established_get_bd_addr(packet, address); 350 printf("AVRCP Controller connected.\n"); 351 return; 352 } 353 case AVRCP_SUBEVENT_CONNECTION_RELEASED: 354 printf("AVRCP Controller Client released.\n"); 355 avrcp_cid = 0; 356 avrcp_browsing_connected = 0; 357 folder_index = 0; 358 memset(folders, 0, sizeof(folders)); 359 return; 360 361 case AVRCP_SUBEVENT_INCOMING_BROWSING_CONNECTION: 362 local_cid = avrcp_subevent_incoming_browsing_connection_get_browsing_cid(packet); 363 printf("AVRCP_SUBEVENT_INCOMING_BROWSING_CONNECTION cid 0x%02x\n", local_cid); 364 if (browsing_cid != 0 && browsing_cid != local_cid) { 365 printf("AVRCP Browsing Client connection failed, expected 0x%02X l2cap cid, received 0x%02X\n", browsing_cid, local_cid); 366 avrcp_browsing_controller_decline_incoming_connection(browsing_cid); 367 return; 368 } 369 browsing_cid = local_cid; 370 printf("AVRCP Browsing Client configure incoming connection, browsing cid 0x%02x\n", browsing_cid); 371 avrcp_browsing_controller_configure_incoming_connection(browsing_cid, ertm_buffer, sizeof(ertm_buffer), &ertm_config); 372 break; 373 374 case AVRCP_SUBEVENT_BROWSING_CONNECTION_ESTABLISHED: { 375 local_cid = avrcp_subevent_browsing_connection_established_get_browsing_cid(packet); 376 printf("AVRCP_SUBEVENT_BROWSING_CONNECTION_ESTABLISHED cid 0x%02x\n", local_cid); 377 if (browsing_cid != 0 && browsing_cid != local_cid) { 378 printf("AVRCP Browsing Client connection failed, expected 0x%02X l2cap cid, received 0x%02X\n", browsing_cid, local_cid); 379 return; 380 } 381 382 status = avrcp_subevent_browsing_connection_established_get_status(packet); 383 if (status != ERROR_CODE_SUCCESS){ 384 printf("AVRCP Browsing Client connection failed: status 0x%02x\n", status); 385 browsing_cid = 0; 386 return; 387 } 388 389 browsing_cid = local_cid; 390 avrcp_browsing_connected = 1; 391 avrcp_subevent_browsing_connection_established_get_bd_addr(packet, address); 392 printf("AVRCP Browsing Client connected\n"); 393 return; 394 } 395 case AVRCP_SUBEVENT_BROWSING_CONNECTION_RELEASED: 396 printf("AVRCP Browsing Controller released\n"); 397 browsing_cid = 0; 398 avrcp_browsing_connected = 0; 399 return; 400 401 case AVRCP_SUBEVENT_BROWSING_DONE: 402 browsing_query_active = 0; 403 browsing_uid_counter = 0; 404 if (avrcp_subevent_browsing_done_get_browsing_status(packet) != AVRCP_BROWSING_ERROR_CODE_SUCCESS){ 405 printf("AVRCP Browsing query done with browsing status 0x%02x, bluetooth status 0x%02x.\n", 406 avrcp_subevent_browsing_done_get_browsing_status(packet), 407 avrcp_subevent_browsing_done_get_bluetooth_status(packet)); 408 break; 409 } 410 browsing_uid_counter = avrcp_subevent_browsing_done_get_uid_counter(packet); 411 printf("DONE, browsing_uid_counter %d.\n", browsing_uid_counter); 412 break; 413 414 default: 415 break; 416 } 417 break; 418 419 default: 420 break; 421 } 422 423 } 424 425 #ifdef HAVE_BTSTACK_STDIN 426 static void show_usage(void){ 427 bd_addr_t iut_address; 428 gap_local_bd_addr(iut_address); 429 printf("\n--- Bluetooth AVRCP Controller Connection Test Console %s ---\n", bd_addr_to_str(iut_address)); 430 printf("c - AVRCP Controller create connection to addr %s\n", bd_addr_to_str(device_addr)); 431 printf("e - AVRCP Browsing Controller create connection to addr %s\n", bd_addr_to_str(device_addr)); 432 printf("E - AVRCP Browsing Controller disconnect\n"); 433 printf("C - AVRCP Controller disconnect\n"); 434 435 printf("I - Set first found player as addressed player\n"); 436 printf("O - Set first found player as browsed player\n"); 437 438 printf("p - Get media players\n"); 439 printf("Q - Browse folders\n"); 440 printf("P - Go up one level\n"); 441 printf("W - Go down one level\n"); 442 printf("T - Browse media items\n"); 443 printf("---\n"); 444 } 445 #endif 446 447 448 #ifdef HAVE_BTSTACK_STDIN 449 static void stdin_process(char cmd){ 450 uint8_t status = ERROR_CODE_SUCCESS; 451 452 if (cmd != 'a' && cmd != 'A' && cmd != 'c' && cmd != 'C'){ 453 if (browsing_query_active){ 454 printf("Query active, try later!\n"); 455 return; 456 } 457 } 458 459 switch (cmd){ 460 case 'c': 461 printf(" - Create AVRCP connection for control to addr %s.\n", bd_addr_to_str(device_addr)); 462 status = avrcp_controller_connect(device_addr, &avrcp_cid); 463 break; 464 case 'C': 465 if (avrcp_connected){ 466 printf(" - AVRCP Controller disconnect from addr %s.\n", bd_addr_to_str(device_addr)); 467 status = avrcp_controller_disconnect(avrcp_cid); 468 break; 469 } 470 printf("AVRCP Controller already disconnected\n"); 471 break; 472 473 case 'e': 474 if (!avrcp_connected) { 475 printf(" You must first create AVRCP connection for control to addr %s.\n", bd_addr_to_str(device_addr)); 476 break; 477 } 478 printf(" - Create AVRCP connection for browsing to addr %s.\n", bd_addr_to_str(device_addr)); 479 status = avrcp_browsing_controller_connect(device_addr, ertm_buffer, sizeof(ertm_buffer), &ertm_config, &browsing_cid); 480 break; 481 case 'E': 482 if (avrcp_browsing_connected){ 483 printf(" - AVRCP Browsing Controller disconnect from addr %s.\n", bd_addr_to_str(device_addr)); 484 status = avrcp_browsing_controller_disconnect(browsing_cid); 485 break; 486 } 487 printf("AVRCP Browsing Controller already disconnected\n"); 488 break; 489 case '\n': 490 case '\r': 491 break; 492 493 default: 494 if (!avrcp_browsing_connected){ 495 show_usage(); 496 printf("Please connect the AVRCP Browsing client\n"); 497 break; 498 } 499 500 switch (cmd) { 501 case 'I': 502 if (player_index < 0) { 503 printf("Get media players first\n"); 504 break; 505 } 506 printf("Set addressed player\n"); 507 status = avrcp_controller_set_addressed_player(avrcp_cid, players[0]); 508 break; 509 case 'O': 510 if (player_index < 0) { 511 printf("Get media players first\n"); 512 break; 513 } 514 printf("Set browsed player\n"); 515 status = avrcp_browsing_controller_set_browsed_player(browsing_cid, players[0]); 516 break; 517 case 'p': 518 printf("AVRCP Browsing: get media players\n"); 519 player_index = -1; 520 status = avrcp_browsing_controller_get_media_players(browsing_cid, 0, 0xFFFFFFFF, AVRCP_MEDIA_ATTR_ALL); 521 break; 522 case 'Q': 523 printf("AVRCP Browsing: browse folders\n"); 524 folder_index = -1; 525 status = avrcp_browsing_controller_browse_file_system(browsing_cid, 0, 0xFFFFFFFF, AVRCP_MEDIA_ATTR_ALL); 526 break; 527 case 'P': 528 printf("AVRCP Browsing: browse media items\n"); 529 avrcp_browsing_controller_browse_media(browsing_cid, 0, 0xFFFFFFFF, AVRCP_MEDIA_ATTR_ALL); 530 break; 531 case 'W': 532 printf("AVRCP Browsing: go up one level\n"); 533 status = avrcp_browsing_controller_go_up_one_level(browsing_cid); 534 folder_index = -1; 535 break; 536 case 'T': 537 if (folder_index < 0 && !parent_folder_set){ 538 printf("AVRCP Browsing: no folders available\n"); 539 break; 540 } 541 if (!parent_folder_set){ 542 parent_folder_set = 1; 543 memcpy(parent_folder_name, folders[0].name, folders[0].name_len); 544 memcpy(parent_folder_uid, folders[0].uid, 8); 545 } 546 printf("AVRCP Browsing: go down one level of %s\n", (char *)parent_folder_name); 547 status = avrcp_browsing_controller_go_down_one_level(browsing_cid, parent_folder_uid); 548 folder_index = -1; 549 break; 550 default: 551 show_usage(); 552 break; 553 } 554 break; 555 } 556 557 if (status != ERROR_CODE_SUCCESS){ 558 printf("Could not perform command, status 0x%2x\n", status); 559 } 560 } 561 #endif 562 /* EXAMPLE_END */ 563