xref: /OK3568_Linux_fs/kernel/Documentation/userspace-api/media/dvb/audio-channel-select.rst (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
2*4882a593Smuzhiyun.. c:namespace:: DTV.audio
3*4882a593Smuzhiyun
4*4882a593Smuzhiyun.. _AUDIO_CHANNEL_SELECT:
5*4882a593Smuzhiyun
6*4882a593Smuzhiyun====================
7*4882a593SmuzhiyunAUDIO_CHANNEL_SELECT
8*4882a593Smuzhiyun====================
9*4882a593Smuzhiyun
10*4882a593SmuzhiyunName
11*4882a593Smuzhiyun----
12*4882a593Smuzhiyun
13*4882a593SmuzhiyunAUDIO_CHANNEL_SELECT
14*4882a593Smuzhiyun
15*4882a593Smuzhiyun.. attention:: This ioctl is deprecated
16*4882a593Smuzhiyun
17*4882a593SmuzhiyunSynopsis
18*4882a593Smuzhiyun--------
19*4882a593Smuzhiyun
20*4882a593Smuzhiyun.. c:macro:: AUDIO_CHANNEL_SELECT
21*4882a593Smuzhiyun
22*4882a593Smuzhiyun``int ioctl(int fd, AUDIO_CHANNEL_SELECT, struct audio_channel_select *select)``
23*4882a593Smuzhiyun
24*4882a593SmuzhiyunArguments
25*4882a593Smuzhiyun---------
26*4882a593Smuzhiyun
27*4882a593Smuzhiyun.. flat-table::
28*4882a593Smuzhiyun    :header-rows:  0
29*4882a593Smuzhiyun    :stub-columns: 0
30*4882a593Smuzhiyun
31*4882a593Smuzhiyun    -
32*4882a593Smuzhiyun
33*4882a593Smuzhiyun       -  int fd
34*4882a593Smuzhiyun
35*4882a593Smuzhiyun       -  File descriptor returned by a previous call to open().
36*4882a593Smuzhiyun
37*4882a593Smuzhiyun    -
38*4882a593Smuzhiyun
39*4882a593Smuzhiyun       -  audio_channel_select_t ch
40*4882a593Smuzhiyun
41*4882a593Smuzhiyun       -  Select the output format of the audio (mono left/right, stereo).
42*4882a593Smuzhiyun
43*4882a593SmuzhiyunDescription
44*4882a593Smuzhiyun-----------
45*4882a593Smuzhiyun
46*4882a593SmuzhiyunThis ioctl is for Digital TV devices only. To control a V4L2 decoder use the
47*4882a593SmuzhiyunV4L2 ``V4L2_CID_MPEG_AUDIO_DEC_PLAYBACK`` control instead.
48*4882a593Smuzhiyun
49*4882a593SmuzhiyunThis ioctl call asks the Audio Device to select the requested channel if
50*4882a593Smuzhiyunpossible.
51*4882a593Smuzhiyun
52*4882a593SmuzhiyunReturn Value
53*4882a593Smuzhiyun------------
54*4882a593Smuzhiyun
55*4882a593SmuzhiyunOn success 0 is returned, on error -1 and the ``errno`` variable is set
56*4882a593Smuzhiyunappropriately. The generic error codes are described at the
57*4882a593Smuzhiyun:ref:`Generic Error Codes <gen-errors>` chapter.
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