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diff --git a/Documentation/media/uapi/v4l/vidioc-g-audio.rst b/Documentation/media/uapi/v4l/vidioc-g-audio.rst deleted file mode 100644 index 7af4fe478ba4..000000000000 --- a/Documentation/media/uapi/v4l/vidioc-g-audio.rst +++ /dev/null @@ -1,135 +0,0 @@ -.. Permission is granted to copy, distribute and/or modify this -.. document under the terms of the GNU Free Documentation License, -.. Version 1.1 or any later version published by the Free Software -.. Foundation, with no Invariant Sections, no Front-Cover Texts -.. and no Back-Cover Texts. A copy of the license is included at -.. Documentation/media/uapi/fdl-appendix.rst. -.. -.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections - -.. _VIDIOC_G_AUDIO: - -************************************ -ioctl VIDIOC_G_AUDIO, VIDIOC_S_AUDIO -************************************ - -Name -==== - -VIDIOC_G_AUDIO - VIDIOC_S_AUDIO - Query or select the current audio input and its attributes - - -Synopsis -======== - -.. c:function:: int ioctl( int fd, VIDIOC_G_AUDIO, struct v4l2_audio *argp ) - :name: VIDIOC_G_AUDIO - -.. c:function:: int ioctl( int fd, VIDIOC_S_AUDIO, const struct v4l2_audio *argp ) - :name: VIDIOC_S_AUDIO - - -Arguments -========= - -``fd`` - File descriptor returned by :ref:`open() <func-open>`. - -``argp`` - Pointer to struct :c:type:`v4l2_audio`. - - -Description -=========== - -To query the current audio input applications zero out the ``reserved`` -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. - -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 -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. - - -.. 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 - - * - __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: - -.. flat-table:: Audio Capability Flags - :header-rows: 0 - :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. - - - -.. tabularcolumns:: |p{6.6cm}|p{2.2cm}|p{8.7cm}| - -.. _audio-mode: - -.. flat-table:: Audio Mode Flags - :header-rows: 0 - :stub-columns: 0 - :widths: 3 1 4 - - * - ``V4L2_AUDMODE_AVL`` - - 0x00001 - - AVL mode is on. - - -Return Value -============ - -On success 0 is returned, on error -1 and the ``errno`` variable is set -appropriately. The generic error codes are described at the -:ref:`Generic Error Codes <gen-errors>` chapter. - -EINVAL - No audio inputs combine with the current video input, or the number - of the selected audio input is out of bounds or it does not combine. |