Documentation/linux_tv/media/dvb/audio_function_calls.rst

   1 .. -*- coding: utf-8; mode: rst -*-
   2
   3 .. _audio_function_calls:
   4
   5 ********************
   6 Audio Function Calls
   7 ********************
   8
   9
  10 .. _audio_fopen:
  11
  12 DVB audio open()
  13 ================
  14
  15 Description
  16 -----------
  17
  18 This system call opens a named audio device (e.g.
  19 /dev/dvb/adapter0/audio0) for subsequent use. When an open() call has
  20 succeeded, the device will be ready for use. The significance of
  21 blocking or non-blocking mode is described in the documentation for
  22 functions where there is a difference. It does not affect the semantics
  23 of the open() call itself. A device opened in blocking mode can later be
  24 put into non-blocking mode (and vice versa) using the F_SETFL command
  25 of the fcntl system call. This is a standard system call, documented in
  26 the Linux manual page for fcntl. Only one user can open the Audio Device
  27 in O_RDWR mode. All other attempts to open the device in this mode will
  28 fail, and an error code will be returned. If the Audio Device is opened
  29 in O_RDONLY mode, the only ioctl call that can be used is
  30 AUDIO_GET_STATUS. All other call will return with an error code.
  31
  32 Synopsis
  33 --------
  34
  35 .. c:function:: int  open(const char *deviceName, int flags)
  36
  37 Arguments
  38 ----------
  39
  40
  41
  42 .. flat-table::
  43     :header-rows:  0
  44     :stub-columns: 0
  45
  46
  47     -  .. row 1
  48
  49        -  const char \*deviceName
  50
  51        -  Name of specific audio device.
  52
  53     -  .. row 2
  54
  55        -  int flags
  56
  57        -  A bit-wise OR of the following flags:
  58
  59     -  .. row 3
  60
  61        -
  62        -  O_RDONLY read-only access
  63
  64     -  .. row 4
  65
  66        -
  67        -  O_RDWR read/write access
  68
  69     -  .. row 5
  70
  71        -
  72        -  O_NONBLOCK open in non-blocking mode
  73
  74     -  .. row 6
  75
  76        -
  77        -  (blocking mode is the default)
  78
  79
  80 Return Value
  81 ------------
  82
  83
  84
  85 .. flat-table::
  86     :header-rows:  0
  87     :stub-columns: 0
  88
  89
  90     -  .. row 1
  91
  92        -  ``ENODEV``
  93
  94        -  Device driver not loaded/available.
  95
  96     -  .. row 2
  97
  98        -  ``EBUSY``
  99
 100        -  Device or resource busy.
 101
 102     -  .. row 3
 103
 104        -  ``EINVAL``
 105
 106        -  Invalid argument.
 107
 108
 109
 110 .. _audio_fclose:
 111
 112 DVB audio close()
 113 =================
 114
 115 Description
 116 -----------
 117
 118 This system call closes a previously opened audio device.
 119
 120 Synopsis
 121 --------
 122
 123 .. c:function:: int  close(int fd)
 124
 125 Arguments
 126 ----------
 127
 128
 129
 130 .. flat-table::
 131     :header-rows:  0
 132     :stub-columns: 0
 133
 134
 135     -  .. row 1
 136
 137        -  int fd
 138
 139        -  File descriptor returned by a previous call to open().
 140
 141
 142 Return Value
 143 ------------
 144
 145
 146
 147 .. flat-table::
 148     :header-rows:  0
 149     :stub-columns: 0
 150
 151
 152     -  .. row 1
 153
 154        -  ``EBADF``
 155
 156        -  fd is not a valid open file descriptor.
 157
 158
 159
 160 .. _audio_fwrite:
 161
 162 DVB audio write()
 163 =================
 164
 165 Description
 166 -----------
 167
 168 This system call can only be used if AUDIO_SOURCE_MEMORY is selected
 169 in the ioctl call AUDIO_SELECT_SOURCE. The data provided shall be in
 170 PES format. If O_NONBLOCK is not specified the function will block
 171 until buffer space is available. The amount of data to be transferred is
 172 implied by count.
 173
 174 Synopsis
 175 --------
 176
 177 .. c:function:: size_t write(int fd, const void *buf, size_t count)
 178
 179 Arguments
 180 ----------
 181
 182
 183
 184 .. flat-table::
 185     :header-rows:  0
 186     :stub-columns: 0
 187
 188
 189     -  .. row 1
 190
 191        -  int fd
 192
 193        -  File descriptor returned by a previous call to open().
 194
 195     -  .. row 2
 196
 197        -  void \*buf
 198
 199        -  Pointer to the buffer containing the PES data.
 200
 201     -  .. row 3
 202
 203        -  size_t count
 204
 205        -  Size of buf.
 206
 207
 208 Return Value
 209 ------------
 210
 211
 212
 213 .. flat-table::
 214     :header-rows:  0
 215     :stub-columns: 0
 216
 217
 218     -  .. row 1
 219
 220        -  ``EPERM``
 221
 222        -  Mode AUDIO_SOURCE_MEMORY not selected.
 223
 224     -  .. row 2
 225
 226        -  ``ENOMEM``
 227
 228        -  Attempted to write more data than the internal buffer can hold.
 229
 230     -  .. row 3
 231
 232        -  ``EBADF``
 233
 234        -  fd is not a valid open file descriptor.
 235
 236
 237
 238 .. _AUDIO_STOP:
 239
 240 AUDIO_STOP
 241 ==========
 242
 243 Description
 244 -----------
 245
 246 This ioctl call asks the Audio Device to stop playing the current
 247 stream.
 248
 249 Synopsis
 250 --------
 251
 252 .. c:function:: int ioctl(int fd, int request = AUDIO_STOP)
 253
 254 Arguments
 255 ----------
 256
 257
 258
 259 .. flat-table::
 260     :header-rows:  0
 261     :stub-columns: 0
 262
 263
 264     -  .. row 1
 265
 266        -  int fd
 267
 268        -  File descriptor returned by a previous call to open().
 269
 270     -  .. row 2
 271
 272        -  int request
 273
 274        -  Equals AUDIO_STOP for this command.
 275
 276
 277 Return Value
 278 ------------
 279
 280 On success 0 is returned, on error -1 and the ``errno`` variable is set
 281 appropriately. The generic error codes are described at the
 282 :ref:`Generic Error Codes <gen-errors>` chapter.
 283
 284
 285 .. _AUDIO_PLAY:
 286
 287 AUDIO_PLAY
 288 ==========
 289
 290 Description
 291 -----------
 292
 293 This ioctl call asks the Audio Device to start playing an audio stream
 294 from the selected source.
 295
 296 Synopsis
 297 --------
 298
 299 .. c:function:: int  ioctl(int fd, int request = AUDIO_PLAY)
 300
 301 Arguments
 302 ----------
 303
 304
 305
 306 .. flat-table::
 307     :header-rows:  0
 308     :stub-columns: 0
 309
 310
 311     -  .. row 1
 312
 313        -  int fd
 314
 315        -  File descriptor returned by a previous call to open().
 316
 317     -  .. row 2
 318
 319        -  int request
 320
 321        -  Equals AUDIO_PLAY for this command.
 322
 323
 324 Return Value
 325 ------------
 326
 327 On success 0 is returned, on error -1 and the ``errno`` variable is set
 328 appropriately. The generic error codes are described at the
 329 :ref:`Generic Error Codes <gen-errors>` chapter.
 330
 331
 332 .. _AUDIO_PAUSE:
 333
 334 AUDIO_PAUSE
 335 ===========
 336
 337 Description
 338 -----------
 339
 340 This ioctl call suspends the audio stream being played. Decoding and
 341 playing are paused. It is then possible to restart again decoding and
 342 playing process of the audio stream using AUDIO_CONTINUE command.
 343
 344 Synopsis
 345 --------
 346
 347 .. c:function:: int  ioctl(int fd, int request = AUDIO_PAUSE)
 348
 349 Arguments
 350 ----------
 351
 352
 353
 354 .. flat-table::
 355     :header-rows:  0
 356     :stub-columns: 0
 357
 358
 359     -  .. row 1
 360
 361        -  int fd
 362
 363        -  File descriptor returned by a previous call to open().
 364
 365     -  .. row 2
 366
 367        -  int request
 368
 369        -  Equals AUDIO_PAUSE for this command.
 370
 371
 372 Return Value
 373 ------------
 374
 375 On success 0 is returned, on error -1 and the ``errno`` variable is set
 376 appropriately. The generic error codes are described at the
 377 :ref:`Generic Error Codes <gen-errors>` chapter.
 378
 379
 380 .. _AUDIO_CONTINUE:
 381
 382 AUDIO_CONTINUE
 383 ==============
 384
 385 Description
 386 -----------
 387
 388 This ioctl restarts the decoding and playing process previously paused
 389 with AUDIO_PAUSE command.
 390
 391 Synopsis
 392 --------
 393
 394 .. c:function:: int  ioctl(int fd, int request = AUDIO_CONTINUE)
 395
 396 Arguments
 397 ----------
 398
 399
 400
 401 .. flat-table::
 402     :header-rows:  0
 403     :stub-columns: 0
 404
 405
 406     -  .. row 1
 407
 408        -  int fd
 409
 410        -  File descriptor returned by a previous call to open().
 411
 412     -  .. row 2
 413
 414        -  int request
 415
 416        -  Equals AUDIO_CONTINUE for this command.
 417
 418
 419 Return Value
 420 ------------
 421
 422 On success 0 is returned, on error -1 and the ``errno`` variable is set
 423 appropriately. The generic error codes are described at the
 424 :ref:`Generic Error Codes <gen-errors>` chapter.
 425
 426
 427 .. _AUDIO_SELECT_SOURCE:
 428
 429 AUDIO_SELECT_SOURCE
 430 ===================
 431
 432 Description
 433 -----------
 434
 435 This ioctl call informs the audio device which source shall be used for
 436 the input data. The possible sources are demux or memory. If
 437 AUDIO_SOURCE_MEMORY is selected, the data is fed to the Audio Device
 438 through the write command.
 439
 440 Synopsis
 441 --------
 442
 443 .. c:function:: int ioctl(int fd, int request = AUDIO_SELECT_SOURCE, audio_stream_source_t source)
 444
 445 Arguments
 446 ----------
 447
 448
 449
 450 .. flat-table::
 451     :header-rows:  0
 452     :stub-columns: 0
 453
 454
 455     -  .. row 1
 456
 457        -  int fd
 458
 459        -  File descriptor returned by a previous call to open().
 460
 461     -  .. row 2
 462
 463        -  int request
 464
 465        -  Equals AUDIO_SELECT_SOURCE for this command.
 466
 467     -  .. row 3
 468
 469        -  audio_stream_source_t source
 470
 471        -  Indicates the source that shall be used for the Audio stream.
 472
 473
 474 Return Value
 475 ------------
 476
 477 On success 0 is returned, on error -1 and the ``errno`` variable is set
 478 appropriately. The generic error codes are described at the
 479 :ref:`Generic Error Codes <gen-errors>` chapter.
 480
 481
 482 .. _AUDIO_SET_MUTE:
 483
 484 AUDIO_SET_MUTE
 485 ==============
 486
 487 Description
 488 -----------
 489
 490 This ioctl is for DVB devices only. To control a V4L2 decoder use the
 491 V4L2 :ref:`VIDIOC_DECODER_CMD` with the
 492 ``V4L2_DEC_CMD_START_MUTE_AUDIO`` flag instead.
 493
 494 This ioctl call asks the audio device to mute the stream that is
 495 currently being played.
 496
 497 Synopsis
 498 --------
 499
 500 .. c:function:: int  ioctl(int fd, int request = AUDIO_SET_MUTE, boolean state)
 501
 502 Arguments
 503 ----------
 504
 505
 506
 507 .. flat-table::
 508     :header-rows:  0
 509     :stub-columns: 0
 510
 511
 512     -  .. row 1
 513
 514        -  int fd
 515
 516        -  File descriptor returned by a previous call to open().
 517
 518     -  .. row 2
 519
 520        -  int request
 521
 522        -  Equals AUDIO_SET_MUTE for this command.
 523
 524     -  .. row 3
 525
 526        -  boolean state
 527
 528        -  Indicates if audio device shall mute or not.
 529
 530     -  .. row 4
 531
 532        -
 533        -  TRUE Audio Mute
 534
 535     -  .. row 5
 536
 537        -
 538        -  FALSE Audio Un-mute
 539
 540
 541 Return Value
 542 ------------
 543
 544 On success 0 is returned, on error -1 and the ``errno`` variable is set
 545 appropriately. The generic error codes are described at the
 546 :ref:`Generic Error Codes <gen-errors>` chapter.
 547
 548
 549 .. _AUDIO_SET_AV_SYNC:
 550
 551 AUDIO_SET_AV_SYNC
 552 =================
 553
 554 Description
 555 -----------
 556
 557 This ioctl call asks the Audio Device to turn ON or OFF A/V
 558 synchronization.
 559
 560 Synopsis
 561 --------
 562
 563 .. c:function:: int  ioctl(int fd, int request = AUDIO_SET_AV_SYNC, boolean state)
 564
 565 Arguments
 566 ----------
 567
 568
 569
 570 .. flat-table::
 571     :header-rows:  0
 572     :stub-columns: 0
 573
 574
 575     -  .. row 1
 576
 577        -  int fd
 578
 579        -  File descriptor returned by a previous call to open().
 580
 581     -  .. row 2
 582
 583        -  int request
 584
 585        -  Equals AUDIO_AV_SYNC for this command.
 586
 587     -  .. row 3
 588
 589        -  boolean state
 590
 591        -  Tells the DVB subsystem if A/V synchronization shall be ON or OFF.
 592
 593     -  .. row 4
 594
 595        -
 596        -  TRUE AV-sync ON
 597
 598     -  .. row 5
 599
 600        -
 601        -  FALSE AV-sync OFF
 602
 603
 604 Return Value
 605 ------------
 606
 607 On success 0 is returned, on error -1 and the ``errno`` variable is set
 608 appropriately. The generic error codes are described at the
 609 :ref:`Generic Error Codes <gen-errors>` chapter.
 610
 611
 612 .. _AUDIO_SET_BYPASS_MODE:
 613
 614 AUDIO_SET_BYPASS_MODE
 615 =====================
 616
 617 Description
 618 -----------
 619
 620 This ioctl call asks the Audio Device to bypass the Audio decoder and
 621 forward the stream without decoding. This mode shall be used if streams
 622 that can’t be handled by the DVB system shall be decoded. Dolby
 623 DigitalTM streams are automatically forwarded by the DVB subsystem if
 624 the hardware can handle it.
 625
 626 Synopsis
 627 --------
 628
 629 .. c:function:: int ioctl(int fd, int request = AUDIO_SET_BYPASS_MODE, boolean mode)
 630
 631 Arguments
 632 ----------
 633
 634
 635
 636 .. flat-table::
 637     :header-rows:  0
 638     :stub-columns: 0
 639
 640
 641     -  .. row 1
 642
 643        -  int fd
 644
 645        -  File descriptor returned by a previous call to open().
 646
 647     -  .. row 2
 648
 649        -  int request
 650
 651        -  Equals AUDIO_SET_BYPASS_MODE for this command.
 652
 653     -  .. row 3
 654
 655        -  boolean mode
 656
 657        -  Enables or disables the decoding of the current Audio stream in
 658           the DVB subsystem.
 659
 660     -  .. row 4
 661
 662        -
 663        -  TRUE Bypass is disabled
 664
 665     -  .. row 5
 666
 667        -
 668        -  FALSE Bypass is enabled
 669
 670
 671 Return Value
 672 ------------
 673
 674 On success 0 is returned, on error -1 and the ``errno`` variable is set
 675 appropriately. The generic error codes are described at the
 676 :ref:`Generic Error Codes <gen-errors>` chapter.
 677
 678
 679 .. _AUDIO_CHANNEL_SELECT:
 680
 681 AUDIO_CHANNEL_SELECT
 682 ====================
 683
 684 Description
 685 -----------
 686
 687 This ioctl is for DVB devices only. To control a V4L2 decoder use the
 688 V4L2 ``V4L2_CID_MPEG_AUDIO_DEC_PLAYBACK`` control instead.
 689
 690 This ioctl call asks the Audio Device to select the requested channel if
 691 possible.
 692
 693 Synopsis
 694 --------
 695
 696 .. c:function:: int ioctl(int fd, int request = AUDIO_CHANNEL_SELECT, audio_channel_select_t)
 697
 698 Arguments
 699 ----------
 700
 701
 702
 703 .. flat-table::
 704     :header-rows:  0
 705     :stub-columns: 0
 706
 707
 708     -  .. row 1
 709
 710        -  int fd
 711
 712        -  File descriptor returned by a previous call to open().
 713
 714     -  .. row 2
 715
 716        -  int request
 717
 718        -  Equals AUDIO_CHANNEL_SELECT for this command.
 719
 720     -  .. row 3
 721
 722        -  audio_channel_select_t ch
 723
 724        -  Select the output format of the audio (mono left/right, stereo).
 725
 726
 727 Return Value
 728 ------------
 729
 730 On success 0 is returned, on error -1 and the ``errno`` variable is set
 731 appropriately. The generic error codes are described at the
 732 :ref:`Generic Error Codes <gen-errors>` chapter.
 733
 734
 735 .. _AUDIO_BILINGUAL_CHANNEL_SELECT:
 736
 737 AUDIO_BILINGUAL_CHANNEL_SELECT
 738 ==============================
 739
 740 Description
 741 -----------
 742
 743 This ioctl is obsolete. Do not use in new drivers. It has been replaced
 744 by the V4L2 ``V4L2_CID_MPEG_AUDIO_DEC_MULTILINGUAL_PLAYBACK`` control
 745 for MPEG decoders controlled through V4L2.
 746
 747 This ioctl call asks the Audio Device to select the requested channel
 748 for bilingual streams if possible.
 749
 750 Synopsis
 751 --------
 752
 753 .. c:function:: int ioctl(int fd, int request = AUDIO_BILINGUAL_CHANNEL_SELECT, audio_channel_select_t)
 754
 755 Arguments
 756 ----------
 757
 758
 759
 760 .. flat-table::
 761     :header-rows:  0
 762     :stub-columns: 0
 763
 764
 765     -  .. row 1
 766
 767        -  int fd
 768
 769        -  File descriptor returned by a previous call to open().
 770
 771     -  .. row 2
 772
 773        -  int request
 774
 775        -  Equals AUDIO_BILINGUAL_CHANNEL_SELECT for this command.
 776
 777     -  .. row 3
 778
 779        -  audio_channel_select_t ch
 780
 781        -  Select the output format of the audio (mono left/right, stereo).
 782
 783
 784 Return Value
 785 ------------
 786
 787 On success 0 is returned, on error -1 and the ``errno`` variable is set
 788 appropriately. The generic error codes are described at the
 789 :ref:`Generic Error Codes <gen-errors>` chapter.
 790
 791
 792 .. _AUDIO_GET_PTS:
 793
 794 AUDIO_GET_PTS
 795 =============
 796
 797 Description
 798 -----------
 799
 800 This ioctl is obsolete. Do not use in new drivers. If you need this
 801 functionality, then please contact the linux-media mailing list
 802 (`https://linuxtv.org/lists.php <https://linuxtv.org/lists.php>`__).
 803
 804 This ioctl call asks the Audio Device to return the current PTS
 805 timestamp.
 806
 807 Synopsis
 808 --------
 809
 810 .. c:function:: int ioctl(int fd, int request = AUDIO_GET_PTS, __u64 *pts)
 811
 812 Arguments
 813 ----------
 814
 815
 816
 817 .. flat-table::
 818     :header-rows:  0
 819     :stub-columns: 0
 820
 821
 822     -  .. row 1
 823
 824        -  int fd
 825
 826        -  File descriptor returned by a previous call to open().
 827
 828     -  .. row 2
 829
 830        -  int request
 831
 832        -  Equals AUDIO_GET_PTS for this command.
 833
 834     -  .. row 3
 835
 836        -  __u64 \*pts
 837
 838        -  Returns the 33-bit timestamp as defined in ITU T-REC-H.222.0 /
 839           ISO/IEC 13818-1.
 840
 841           The PTS should belong to the currently played frame if possible,
 842           but may also be a value close to it like the PTS of the last
 843           decoded frame or the last PTS extracted by the PES parser.
 844
 845
 846 Return Value
 847 ------------
 848
 849 On success 0 is returned, on error -1 and the ``errno`` variable is set
 850 appropriately. The generic error codes are described at the
 851 :ref:`Generic Error Codes <gen-errors>` chapter.
 852
 853
 854 .. _AUDIO_GET_STATUS:
 855
 856 AUDIO_GET_STATUS
 857 ================
 858
 859 Description
 860 -----------
 861
 862 This ioctl call asks the Audio Device to return the current state of the
 863 Audio Device.
 864
 865 Synopsis
 866 --------
 867
 868 .. c:function:: int ioctl(int fd, int request = AUDIO_GET_STATUS, struct audio_status *status)
 869
 870 Arguments
 871 ----------
 872
 873
 874
 875 .. flat-table::
 876     :header-rows:  0
 877     :stub-columns: 0
 878
 879
 880     -  .. row 1
 881
 882        -  int fd
 883
 884        -  File descriptor returned by a previous call to open().
 885
 886     -  .. row 2
 887
 888        -  int request
 889
 890        -  Equals AUDIO_GET_STATUS for this command.
 891
 892     -  .. row 3
 893
 894        -  struct audio_status \*status
 895
 896        -  Returns the current state of Audio Device.
 897
 898
 899 Return Value
 900 ------------
 901
 902 On success 0 is returned, on error -1 and the ``errno`` variable is set
 903 appropriately. The generic error codes are described at the
 904 :ref:`Generic Error Codes <gen-errors>` chapter.
 905
 906
 907 .. _AUDIO_GET_CAPABILITIES:
 908
 909 AUDIO_GET_CAPABILITIES
 910 ======================
 911
 912 Description
 913 -----------
 914
 915 This ioctl call asks the Audio Device to tell us about the decoding
 916 capabilities of the audio hardware.
 917
 918 Synopsis
 919 --------
 920
 921 .. c:function:: int ioctl(int fd, int request = AUDIO_GET_CAPABILITIES, unsigned int *cap)
 922
 923 Arguments
 924 ----------
 925
 926
 927
 928 .. flat-table::
 929     :header-rows:  0
 930     :stub-columns: 0
 931
 932
 933     -  .. row 1
 934
 935        -  int fd
 936
 937        -  File descriptor returned by a previous call to open().
 938
 939     -  .. row 2
 940
 941        -  int request
 942
 943        -  Equals AUDIO_GET_CAPABILITIES for this command.
 944
 945     -  .. row 3
 946
 947        -  unsigned int \*cap
 948
 949        -  Returns a bit array of supported sound formats.
 950
 951
 952 Return Value
 953 ------------
 954
 955 On success 0 is returned, on error -1 and the ``errno`` variable is set
 956 appropriately. The generic error codes are described at the
 957 :ref:`Generic Error Codes <gen-errors>` chapter.
 958
 959
 960 .. _AUDIO_CLEAR_BUFFER:
 961
 962 AUDIO_CLEAR_BUFFER
 963 ==================
 964
 965 Description
 966 -----------
 967
 968 This ioctl call asks the Audio Device to clear all software and hardware
 969 buffers of the audio decoder device.
 970
 971 Synopsis
 972 --------
 973
 974 .. c:function:: int  ioctl(int fd, int request = AUDIO_CLEAR_BUFFER)
 975
 976 Arguments
 977 ----------
 978
 979
 980
 981 .. flat-table::
 982     :header-rows:  0
 983     :stub-columns: 0
 984
 985
 986     -  .. row 1
 987
 988        -  int fd
 989
 990        -  File descriptor returned by a previous call to open().
 991
 992     -  .. row 2
 993
 994        -  int request
 995
 996        -  Equals AUDIO_CLEAR_BUFFER for this command.
 997
 998
 999 Return Value
1000 ------------
1001
1002 On success 0 is returned, on error -1 and the ``errno`` variable is set
1003 appropriately. The generic error codes are described at the
1004 :ref:`Generic Error Codes <gen-errors>` chapter.
1005
1006
1007 .. _AUDIO_SET_ID:
1008
1009 AUDIO_SET_ID
1010 ============
1011
1012 Description
1013 -----------
1014
1015 This ioctl selects which sub-stream is to be decoded if a program or
1016 system stream is sent to the video device. If no audio stream type is
1017 set the id has to be in [0xC0,0xDF] for MPEG sound, in [0x80,0x87] for
1018 AC3 and in [0xA0,0xA7] for LPCM. More specifications may follow for
1019 other stream types. If the stream type is set the id just specifies the
1020 substream id of the audio stream and only the first 5 bits are
1021 recognized.
1022
1023 Synopsis
1024 --------
1025
1026 .. c:function:: int  ioctl(int fd, int request = AUDIO_SET_ID, int id)
1027
1028 Arguments
1029 ----------
1030
1031
1032
1033 .. flat-table::
1034     :header-rows:  0
1035     :stub-columns: 0
1036
1037
1038     -  .. row 1
1039
1040        -  int fd
1041
1042        -  File descriptor returned by a previous call to open().
1043
1044     -  .. row 2
1045
1046        -  int request
1047
1048        -  Equals AUDIO_SET_ID for this command.
1049
1050     -  .. row 3
1051
1052        -  int id
1053
1054        -  audio sub-stream id
1055
1056
1057 Return Value
1058 ------------
1059
1060 On success 0 is returned, on error -1 and the ``errno`` variable is set
1061 appropriately. The generic error codes are described at the
1062 :ref:`Generic Error Codes <gen-errors>` chapter.
1063
1064
1065 .. _AUDIO_SET_MIXER:
1066
1067 AUDIO_SET_MIXER
1068 ===============
1069
1070 Description
1071 -----------
1072
1073 This ioctl lets you adjust the mixer settings of the audio decoder.
1074
1075 Synopsis
1076 --------
1077
1078 .. c:function:: int ioctl(int fd, int request = AUDIO_SET_MIXER, audio_mixer_t *mix)
1079
1080 Arguments
1081 ----------
1082
1083
1084
1085 .. flat-table::
1086     :header-rows:  0
1087     :stub-columns: 0
1088
1089
1090     -  .. row 1
1091
1092        -  int fd
1093
1094        -  File descriptor returned by a previous call to open().
1095
1096     -  .. row 2
1097
1098        -  int request
1099
1100        -  Equals AUDIO_SET_ID for this command.
1101
1102     -  .. row 3
1103
1104        -  audio_mixer_t \*mix
1105
1106        -  mixer settings.
1107
1108
1109 Return Value
1110 ------------
1111
1112 On success 0 is returned, on error -1 and the ``errno`` variable is set
1113 appropriately. The generic error codes are described at the
1114 :ref:`Generic Error Codes <gen-errors>` chapter.
1115
1116
1117 .. _AUDIO_SET_STREAMTYPE:
1118
1119 AUDIO_SET_STREAMTYPE
1120 ====================
1121
1122 Description
1123 -----------
1124
1125 This ioctl tells the driver which kind of audio stream to expect. This
1126 is useful if the stream offers several audio sub-streams like LPCM and
1127 AC3.
1128
1129 Synopsis
1130 --------
1131
1132 .. c:function:: int  ioctl(fd, int request = AUDIO_SET_STREAMTYPE, int type)
1133
1134 Arguments
1135 ----------
1136
1137
1138
1139 .. flat-table::
1140     :header-rows:  0
1141     :stub-columns: 0
1142
1143
1144     -  .. row 1
1145
1146        -  int fd
1147
1148        -  File descriptor returned by a previous call to open().
1149
1150     -  .. row 2
1151
1152        -  int request
1153
1154        -  Equals AUDIO_SET_STREAMTYPE for this command.
1155
1156     -  .. row 3
1157
1158        -  int type
1159
1160        -  stream type
1161
1162
1163 Return Value
1164 ------------
1165
1166 On success 0 is returned, on error -1 and the ``errno`` variable is set
1167 appropriately. The generic error codes are described at the
1168 :ref:`Generic Error Codes <gen-errors>` chapter.
1169
1170
1171
1172 .. flat-table::
1173     :header-rows:  0
1174     :stub-columns: 0
1175
1176
1177     -  .. row 1
1178
1179        -  ``EINVAL``
1180
1181        -  type is not a valid or supported stream type.
1182
1183
1184
1185 .. _AUDIO_SET_EXT_ID:
1186
1187 AUDIO_SET_EXT_ID
1188 ================
1189
1190 Description
1191 -----------
1192
1193 This ioctl can be used to set the extension id for MPEG streams in DVD
1194 playback. Only the first 3 bits are recognized.
1195
1196 Synopsis
1197 --------
1198
1199 .. c:function:: int  ioctl(fd, int request = AUDIO_SET_EXT_ID, int id)
1200
1201 Arguments
1202 ----------
1203
1204
1205
1206 .. flat-table::
1207     :header-rows:  0
1208     :stub-columns: 0
1209
1210
1211     -  .. row 1
1212
1213        -  int fd
1214
1215        -  File descriptor returned by a previous call to open().
1216
1217     -  .. row 2
1218
1219        -  int request
1220
1221        -  Equals AUDIO_SET_EXT_ID for this command.
1222
1223     -  .. row 3
1224
1225        -  int id
1226
1227        -  audio sub_stream_id
1228
1229
1230 Return Value
1231 ------------
1232
1233 On success 0 is returned, on error -1 and the ``errno`` variable is set
1234 appropriately. The generic error codes are described at the
1235 :ref:`Generic Error Codes <gen-errors>` chapter.
1236
1237
1238
1239 .. flat-table::
1240     :header-rows:  0
1241     :stub-columns: 0
1242
1243
1244     -  .. row 1
1245
1246        -  ``EINVAL``
1247
1248        -  id is not a valid id.
1249
1250
1251
1252 .. _AUDIO_SET_ATTRIBUTES:
1253
1254 AUDIO_SET_ATTRIBUTES
1255 ====================
1256
1257 Description
1258 -----------
1259
1260 This ioctl is intended for DVD playback and allows you to set certain
1261 information about the audio stream.
1262
1263 Synopsis
1264 --------
1265
1266 .. c:function:: int ioctl(fd, int request = AUDIO_SET_ATTRIBUTES, audio_attributes_t attr )
1267
1268 Arguments
1269 ----------
1270
1271
1272
1273 .. flat-table::
1274     :header-rows:  0
1275     :stub-columns: 0
1276
1277
1278     -  .. row 1
1279
1280        -  int fd
1281
1282        -  File descriptor returned by a previous call to open().
1283
1284     -  .. row 2
1285
1286        -  int request
1287
1288        -  Equals AUDIO_SET_ATTRIBUTES for this command.
1289
1290     -  .. row 3
1291
1292        -  audio_attributes_t attr
1293
1294        -  audio attributes according to section ??
1295
1296
1297 Return Value
1298 ------------
1299
1300 On success 0 is returned, on error -1 and the ``errno`` variable is set
1301 appropriately. The generic error codes are described at the
1302 :ref:`Generic Error Codes <gen-errors>` chapter.
1303
1304
1305
1306 .. flat-table::
1307     :header-rows:  0
1308     :stub-columns: 0
1309
1310
1311     -  .. row 1
1312
1313        -  ``EINVAL``
1314
1315        -  attr is not a valid or supported attribute setting.
1316
1317
1318
1319 .. _AUDIO_SET_KARAOKE:
1320
1321 AUDIO_SET_KARAOKE
1322 =================
1323
1324 Description
1325 -----------
1326
1327 This ioctl allows one to set the mixer settings for a karaoke DVD.
1328
1329 Synopsis
1330 --------
1331
1332 .. c:function:: int ioctl(fd, int request = AUDIO_SET_KARAOKE, audio_karaoke_t *karaoke)
1333
1334 Arguments
1335 ----------
1336
1337
1338
1339 .. flat-table::
1340     :header-rows:  0
1341     :stub-columns: 0
1342
1343
1344     -  .. row 1
1345
1346        -  int fd
1347
1348        -  File descriptor returned by a previous call to open().
1349
1350     -  .. row 2
1351
1352        -  int request
1353
1354        -  Equals AUDIO_SET_KARAOKE for this command.
1355
1356     -  .. row 3
1357
1358        -  audio_karaoke_t \*karaoke
1359
1360        -  karaoke settings according to section ??.
1361
1362
1363 Return Value
1364 ------------
1365
1366 On success 0 is returned, on error -1 and the ``errno`` variable is set
1367 appropriately. The generic error codes are described at the
1368 :ref:`Generic Error Codes <gen-errors>` chapter.
1369
1370
1371
1372 .. flat-table::
1373     :header-rows:  0
1374     :stub-columns: 0
1375
1376
1377     -  .. row 1
1378
1379        -  ``EINVAL``
1380
1381        -  karaoke is not a valid or supported karaoke setting.