mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-29 07:34:06 +08:00
bff8ff6528
The V4L2_INPUT_TYPE_CAMERA and V4L2_OUTPUT_TYPE_ANALOG descriptions were hopelessly out of date. Fix this, and also fix a few style issues in these documents. Finally add the missing documentation for V4L2_OUTPUT_TYPE_ANALOGVGAOVERLAY (only used by the zoran driver). Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
158 lines
4.4 KiB
ReStructuredText
158 lines
4.4 KiB
ReStructuredText
.. -*- coding: utf-8; mode: rst -*-
|
|
|
|
.. _VIDIOC_ENUMOUTPUT:
|
|
|
|
***********************
|
|
ioctl VIDIOC_ENUMOUTPUT
|
|
***********************
|
|
|
|
Name
|
|
====
|
|
|
|
VIDIOC_ENUMOUTPUT - Enumerate video outputs
|
|
|
|
|
|
Synopsis
|
|
========
|
|
|
|
.. c:function:: int ioctl( int fd, VIDIOC_ENUMOUTPUT, struct v4l2_output *argp )
|
|
:name: VIDIOC_ENUMOUTPUT
|
|
|
|
|
|
Arguments
|
|
=========
|
|
|
|
``fd``
|
|
File descriptor returned by :ref:`open() <func-open>`.
|
|
|
|
``argp``
|
|
|
|
|
|
Description
|
|
===========
|
|
|
|
To query the attributes of a video outputs applications initialize the
|
|
``index`` field of struct :c:type:`v4l2_output` and call
|
|
the :ref:`VIDIOC_ENUMOUTPUT` with a pointer to this structure.
|
|
Drivers fill the rest of the structure or return an ``EINVAL`` error code
|
|
when the index is out of bounds. To enumerate all outputs applications
|
|
shall begin at index zero, incrementing by one until the driver returns
|
|
``EINVAL``.
|
|
|
|
|
|
.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.7cm}|
|
|
|
|
.. c:type:: v4l2_output
|
|
|
|
.. flat-table:: struct v4l2_output
|
|
:header-rows: 0
|
|
:stub-columns: 0
|
|
:widths: 1 1 2
|
|
|
|
* - __u32
|
|
- ``index``
|
|
- Identifies the output, set by the application.
|
|
* - __u8
|
|
- ``name``\ [32]
|
|
- Name of the video output, a NUL-terminated ASCII string, for
|
|
example: "Vout". This information is intended for the user,
|
|
preferably the connector label on the device itself.
|
|
* - __u32
|
|
- ``type``
|
|
- Type of the output, see :ref:`output-type`.
|
|
* - __u32
|
|
- ``audioset``
|
|
- Drivers can enumerate up to 32 video and audio outputs. This field
|
|
shows which audio outputs were selectable as the current output if
|
|
this was the currently selected video output. It is a bit mask.
|
|
The LSB corresponds to audio output 0, the MSB to output 31. Any
|
|
number of bits can be set, or none.
|
|
|
|
When the driver does not enumerate audio outputs no bits must be
|
|
set. Applications shall not interpret this as lack of audio
|
|
support. Drivers may automatically select audio outputs without
|
|
enumerating them.
|
|
|
|
For details on audio outputs and how to select the current output
|
|
see :ref:`audio`.
|
|
* - __u32
|
|
- ``modulator``
|
|
- Output devices can have zero or more RF modulators. When the
|
|
``type`` is ``V4L2_OUTPUT_TYPE_MODULATOR`` this is an RF connector
|
|
and this field identifies the modulator. It corresponds to struct
|
|
:c:type:`v4l2_modulator` field ``index``. For
|
|
details on modulators see :ref:`tuner`.
|
|
* - :ref:`v4l2_std_id <v4l2-std-id>`
|
|
- ``std``
|
|
- Every video output supports one or more different video standards.
|
|
This field is a set of all supported standards. For details on
|
|
video standards and how to switch see :ref:`standard`.
|
|
* - __u32
|
|
- ``capabilities``
|
|
- This field provides capabilities for the output. See
|
|
:ref:`output-capabilities` for flags.
|
|
* - __u32
|
|
- ``reserved``\ [3]
|
|
- Reserved for future extensions. Drivers must set the array to
|
|
zero.
|
|
|
|
|
|
|
|
.. tabularcolumns:: |p{7.0cm}|p{1.8cm}|p{8.7cm}|
|
|
|
|
.. _output-type:
|
|
|
|
.. flat-table:: Output Type
|
|
:header-rows: 0
|
|
:stub-columns: 0
|
|
:widths: 3 1 4
|
|
|
|
* - ``V4L2_OUTPUT_TYPE_MODULATOR``
|
|
- 1
|
|
- This output is an analog TV modulator.
|
|
* - ``V4L2_OUTPUT_TYPE_ANALOG``
|
|
- 2
|
|
- Any non-modulator video output, for example Composite Video,
|
|
S-Video, HDMI. The naming as ``_TYPE_ANALOG`` is historical,
|
|
today we would have called it ``_TYPE_VIDEO``.
|
|
* - ``V4L2_OUTPUT_TYPE_ANALOGVGAOVERLAY``
|
|
- 3
|
|
- The video output will be copied to a :ref:`video overlay <overlay>`.
|
|
|
|
|
|
|
|
.. tabularcolumns:: |p{6.6cm}|p{2.2cm}|p{8.7cm}|
|
|
|
|
.. _output-capabilities:
|
|
|
|
.. flat-table:: Output capabilities
|
|
:header-rows: 0
|
|
:stub-columns: 0
|
|
:widths: 3 1 4
|
|
|
|
* - ``V4L2_OUT_CAP_DV_TIMINGS``
|
|
- 0x00000002
|
|
- This output supports setting video timings by using
|
|
``VIDIOC_S_DV_TIMINGS``.
|
|
* - ``V4L2_OUT_CAP_STD``
|
|
- 0x00000004
|
|
- This output supports setting the TV standard by using
|
|
``VIDIOC_S_STD``.
|
|
* - ``V4L2_OUT_CAP_NATIVE_SIZE``
|
|
- 0x00000008
|
|
- This output supports setting the native size using the
|
|
``V4L2_SEL_TGT_NATIVE_SIZE`` selection target, see
|
|
:ref:`v4l2-selections-common`.
|
|
|
|
|
|
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
|
|
The struct :c:type:`v4l2_output` ``index`` is out of
|
|
bounds.
|