diff options
Diffstat (limited to 'Documentation/media/uapi/v4l/vidioc-g-audio.rst')
| -rw-r--r-- | Documentation/media/uapi/v4l/vidioc-g-audio.rst | 125 |
1 files changed, 45 insertions, 80 deletions
diff --git a/Documentation/media/uapi/v4l/vidioc-g-audio.rst b/Documentation/media/uapi/v4l/vidioc-g-audio.rst index cccbcdb8c463..5b67e81a0db6 100644 --- a/Documentation/media/uapi/v4l/vidioc-g-audio.rst +++ b/Documentation/media/uapi/v4l/vidioc-g-audio.rst @@ -15,9 +15,11 @@ VIDIOC_G_AUDIO - VIDIOC_S_AUDIO - Query or select the current audio input and it Synopsis ======== -.. cpp:function:: int ioctl( int fd, int request, struct v4l2_audio *argp ) +.. c:function:: int ioctl( int fd, VIDIOC_G_AUDIO, struct v4l2_audio *argp ) + :name: VIDIOC_G_AUDIO -.. cpp:function:: int ioctl( int fd, int request, const struct v4l2_audio *argp ) +.. c:function:: int ioctl( int fd, VIDIOC_S_AUDIO, const struct v4l2_audio *argp ) + :name: VIDIOC_S_AUDIO Arguments @@ -26,9 +28,6 @@ Arguments ``fd`` File descriptor returned by :ref:`open() <func-open>`. -``request`` - VIDIOC_G_AUDIO, VIDIOC_S_AUDIO - ``argp`` @@ -36,7 +35,7 @@ Description =========== To query the current audio input applications zero out the ``reserved`` -array of a struct :ref:`v4l2_audio <v4l2-audio>` and call the +array of a struct :c:type:`v4l2_audio` and call the :ref:`VIDIOC_G_AUDIO <VIDIOC_G_AUDIO>` ioctl with a pointer to this structure. Drivers fill the rest of the structure or return an ``EINVAL`` error code when the device has no audio inputs, or none which combine with the current video input. @@ -44,65 +43,44 @@ has no audio inputs, or none which combine with the current video input. Audio inputs have one writable property, the audio mode. To select the current audio input *and* change the audio mode, applications initialize the ``index`` and ``mode`` fields, and the ``reserved`` array of a -:ref:`struct v4l2_audio <v4l2-audio>` structure and call the :ref:`VIDIOC_S_AUDIO <VIDIOC_G_AUDIO>` +struct :c:type:`v4l2_audio` structure and call the :ref:`VIDIOC_S_AUDIO <VIDIOC_G_AUDIO>` ioctl. Drivers may switch to a different audio mode if the request cannot be satisfied. However, this is a write-only ioctl, it does not return the actual new audio mode. -.. _v4l2-audio: +.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.7cm}| + +.. c:type:: v4l2_audio .. flat-table:: struct v4l2_audio :header-rows: 0 :stub-columns: 0 :widths: 1 1 2 - - - .. row 1 - - - __u32 - - - ``index`` - - - Identifies the audio input, set by the driver or application. - - - .. row 2 - - - __u8 - - - ``name``\ [32] - - - Name of the audio input, a NUL-terminated ASCII string, for - example: "Line In". This information is intended for the user, - preferably the connector label on the device itself. - - - .. row 3 - - - __u32 - - - ``capability`` - - - Audio capability flags, see :ref:`audio-capability`. - - - .. row 4 - - - __u32 - - - ``mode`` - - - Audio mode flags set by drivers and applications (on - :ref:`VIDIOC_S_AUDIO <VIDIOC_G_AUDIO>` ioctl), see :ref:`audio-mode`. - - - .. row 5 - - - __u32 - - - ``reserved``\ [2] - - - Reserved for future extensions. Drivers and applications must set - the array to zero. - - + * - __u32 + - ``index`` + - Identifies the audio input, set by the driver or application. + * - __u8 + - ``name``\ [32] + - Name of the audio input, a NUL-terminated ASCII string, for + example: "Line In". This information is intended for the user, + preferably the connector label on the device itself. + * - __u32 + - ``capability`` + - Audio capability flags, see :ref:`audio-capability`. + * - __u32 + - ``mode`` + - Audio mode flags set by drivers and applications (on + :ref:`VIDIOC_S_AUDIO <VIDIOC_G_AUDIO>` ioctl), see :ref:`audio-mode`. + * - __u32 + - ``reserved``\ [2] + - Reserved for future extensions. Drivers and applications must set + the array to zero. + + + +.. tabularcolumns:: |p{6.6cm}|p{2.2cm}|p{8.7cm}| .. _audio-capability: @@ -111,27 +89,19 @@ return the actual new audio mode. :stub-columns: 0 :widths: 3 1 4 + * - ``V4L2_AUDCAP_STEREO`` + - 0x00001 + - This is a stereo input. The flag is intended to automatically + disable stereo recording etc. when the signal is always monaural. + The API provides no means to detect if stereo is *received*, + unless the audio input belongs to a tuner. + * - ``V4L2_AUDCAP_AVL`` + - 0x00002 + - Automatic Volume Level mode is supported. - - .. row 1 - - - ``V4L2_AUDCAP_STEREO`` - - - 0x00001 - - - This is a stereo input. The flag is intended to automatically - disable stereo recording etc. when the signal is always monaural. - The API provides no means to detect if stereo is *received*, - unless the audio input belongs to a tuner. - - - .. row 2 - - - ``V4L2_AUDCAP_AVL`` - - - 0x00002 - - - Automatic Volume Level mode is supported. +.. tabularcolumns:: |p{6.6cm}|p{2.2cm}|p{8.7cm}| .. _audio-mode: @@ -140,14 +110,9 @@ return the actual new audio mode. :stub-columns: 0 :widths: 3 1 4 - - - .. row 1 - - - ``V4L2_AUDMODE_AVL`` - - - 0x00001 - - - AVL mode is on. + * - ``V4L2_AUDMODE_AVL`` + - 0x00001 + - AVL mode is on. Return Value |