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linux-next/Documentation/media/uapi/v4l/vidioc-g-std.rst
Mauro Carvalho Chehab fc78c7c7a1 [media] docs-rst: simplify c:type: cross references
Instead of using c:type:`struct foo <foo>`, use:
	struct c:type:`foo`

This patch was generated via this shell script:

	for i in `find Documentation/media -type f`; do perl -ne 'if (m/\:c\:type\:\`struct\s+(\S+)\s*\<(\S+)\>\`/) { $s=$1; $r=$2; if ($s eq $r) { s/\:c\:type\:\`struct\s+(\S+)\s*\<(\S+)\>\`/struct :c:type:`$2`/; s/struct\s+struct/struct/;  s/(struct\s+\:c\:type\:\`\S+\`)\s+structure/$1/;  }} print $_' <$i >a && mv a $i; done

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-09-09 09:54:54 -03:00

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ReStructuredText

.. -*- coding: utf-8; mode: rst -*-
.. _VIDIOC_G_STD:
********************************
ioctl VIDIOC_G_STD, VIDIOC_S_STD
********************************
Name
====
VIDIOC_G_STD - VIDIOC_S_STD - Query or select the video standard of the current input
Synopsis
========
.. c:function:: int ioctl( int fd, VIDIOC_G_STD, v4l2_std_id *argp )
:name: VIDIOC_G_STD
.. c:function:: int ioctl( int fd, VIDIOC_S_STD, const v4l2_std_id *argp )
:name: VIDIOC_S_STD
Arguments
=========
``fd``
File descriptor returned by :ref:`open() <func-open>`.
``argp``
Description
===========
To query and select the current video standard applications use the
:ref:`VIDIOC_G_STD <VIDIOC_G_STD>` and :ref:`VIDIOC_S_STD <VIDIOC_G_STD>` ioctls which take a pointer to a
:ref:`v4l2_std_id <v4l2-std-id>` type as argument. :ref:`VIDIOC_G_STD <VIDIOC_G_STD>`
can return a single flag or a set of flags as in struct
:c:type:`v4l2_standard` field ``id``. The flags must be
unambiguous such that they appear in only one enumerated
struct :c:type:`v4l2_standard` structure.
:ref:`VIDIOC_S_STD <VIDIOC_G_STD>` accepts one or more flags, being a write-only ioctl it
does not return the actual new standard as :ref:`VIDIOC_G_STD <VIDIOC_G_STD>` does. When
no flags are given or the current input does not support the requested
standard the driver returns an ``EINVAL`` error code. When the standard set
is ambiguous drivers may return ``EINVAL`` or choose any of the requested
standards. If the current input or output does not support standard
video timings (e.g. if :ref:`VIDIOC_ENUMINPUT`
does not set the ``V4L2_IN_CAP_STD`` flag), then ``ENODATA`` error code is
returned.
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 :ref:`VIDIOC_S_STD <VIDIOC_G_STD>` parameter was unsuitable.
ENODATA
Standard video timings are not supported for this input or output.