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OpenCloudOS-Kernel/Documentation/media/uapi/v4l/vidioc-querystd.rst

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doc-rst: linux_tv DocBook to reST migration (docs-next) This is the restructuredText (reST) migration of the ``media`` DocBook-XML set from the linux_tv project. Signed-off-by: Markus Heiser <markus.heiser@darmarIT.de> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-06-30 21:18:56 +08:00
.. -*- coding: utf-8; mode: rst -*-
doc-rst: linux_tv: Replace reference names to match ioctls Due to a limitation at the DocBook language, the references were using lowercase and slashes, instead of the name of the ioctls. On ReST, make them identical. This will hopefully help to cleanup the code a little bit. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-07-02 00:42:29 +08:00
.. _VIDIOC_QUERYSTD:
doc-rst: linux_tv DocBook to reST migration (docs-next) This is the restructuredText (reST) migration of the ``media`` DocBook-XML set from the linux_tv project. Signed-off-by: Markus Heiser <markus.heiser@darmarIT.de> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-06-30 21:18:56 +08:00
*********************
ioctl VIDIOC_QUERYSTD
*********************
doc-rst: linux_tv: don't use uppercases for syscall sections On the syscall conversions, we used uppercase for the sections, but this is too bold. So, convert them to Camel Case, as it looks visually better. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-07-06 02:14:35 +08:00
Name
doc-rst: linux_tv: reformat all syscall pages The syscall pages are written to be used also as man-pages. However, they don't match the format used by kernel-doc generated pages from DocBook. Rewrite them to match it. One side effect is that now all such pages at the book will have the same format, reducing the format differences between DVB and the other parts of the book. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-07-05 18:58:48 +08:00
====
doc-rst: linux_tv DocBook to reST migration (docs-next) This is the restructuredText (reST) migration of the ``media`` DocBook-XML set from the linux_tv project. Signed-off-by: Markus Heiser <markus.heiser@darmarIT.de> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-06-30 21:18:56 +08:00
doc-rst: linux_tv: reformat all syscall pages The syscall pages are written to be used also as man-pages. However, they don't match the format used by kernel-doc generated pages from DocBook. Rewrite them to match it. One side effect is that now all such pages at the book will have the same format, reducing the format differences between DVB and the other parts of the book. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-07-05 18:58:48 +08:00
VIDIOC_QUERYSTD - Sense the video standard received by the current input
doc-rst: linux_tv DocBook to reST migration (docs-next) This is the restructuredText (reST) migration of the ``media`` DocBook-XML set from the linux_tv project. Signed-off-by: Markus Heiser <markus.heiser@darmarIT.de> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-06-30 21:18:56 +08:00
doc-rst: linux_tv: don't use uppercases for syscall sections On the syscall conversions, we used uppercase for the sections, but this is too bold. So, convert them to Camel Case, as it looks visually better. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-07-06 02:14:35 +08:00
Synopsis
doc-rst: linux_tv DocBook to reST migration (docs-next) This is the restructuredText (reST) migration of the ``media`` DocBook-XML set from the linux_tv project. Signed-off-by: Markus Heiser <markus.heiser@darmarIT.de> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-06-30 21:18:56 +08:00
========
doc-rst: linux_tv: supress lots of warnings The c language parser checks if there are duplicated object definitions. That causes lots of warnings like: WARNING: duplicate C object description of ioctl Let's remove those by telling Sphinx that the language for those objects are c++. The look of the descriptions will be close, and the warnings will be gone. Please notice that we had to keep a few of them as C, as the c++ parser seems to be broken when it finds an enum. Yet, this reduced from 219 warnings to 143, with is a good thing. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-07-02 20:49:16 +08:00
.. cpp:function:: int ioctl( int fd, int request, v4l2_std_id *argp )
doc-rst: linux_tv DocBook to reST migration (docs-next) This is the restructuredText (reST) migration of the ``media`` DocBook-XML set from the linux_tv project. Signed-off-by: Markus Heiser <markus.heiser@darmarIT.de> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-06-30 21:18:56 +08:00
doc-rst: linux_tv: reformat all syscall pages The syscall pages are written to be used also as man-pages. However, they don't match the format used by kernel-doc generated pages from DocBook. Rewrite them to match it. One side effect is that now all such pages at the book will have the same format, reducing the format differences between DVB and the other parts of the book. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-07-05 18:58:48 +08:00
doc-rst: linux_tv: don't use uppercases for syscall sections On the syscall conversions, we used uppercase for the sections, but this is too bold. So, convert them to Camel Case, as it looks visually better. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-07-06 02:14:35 +08:00
Arguments
doc-rst: linux_tv DocBook to reST migration (docs-next) This is the restructuredText (reST) migration of the ``media`` DocBook-XML set from the linux_tv project. Signed-off-by: Markus Heiser <markus.heiser@darmarIT.de> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-06-30 21:18:56 +08:00
=========
``fd``
File descriptor returned by :ref:`open() <func-open>`.
``request``
VIDIOC_QUERYSTD
``argp``
doc-rst: linux_tv: don't use uppercases for syscall sections On the syscall conversions, we used uppercase for the sections, but this is too bold. So, convert them to Camel Case, as it looks visually better. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-07-06 02:14:35 +08:00
Description
doc-rst: linux_tv DocBook to reST migration (docs-next) This is the restructuredText (reST) migration of the ``media`` DocBook-XML set from the linux_tv project. Signed-off-by: Markus Heiser <markus.heiser@darmarIT.de> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-06-30 21:18:56 +08:00
===========
The hardware may be able to detect the current video standard
doc-rst: linux_tv: convert lots of consts to references There were lots of consts at the media docbook that should be, instead, references. Convert the ones that can easily be done by an automatic script. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-07-02 01:33:56 +08:00
automatically. To do so, applications call :ref:`VIDIOC_QUERYSTD` with a
doc-rst: linux_tv DocBook to reST migration (docs-next) This is the restructuredText (reST) migration of the ``media`` DocBook-XML set from the linux_tv project. Signed-off-by: Markus Heiser <markus.heiser@darmarIT.de> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-06-30 21:18:56 +08:00
pointer to a :ref:`v4l2_std_id <v4l2-std-id>` type. The driver
stores here a set of candidates, this can be a single flag or a set of
supported standards if for example the hardware can only distinguish
between 50 and 60 Hz systems. If no signal was detected, then the driver
will return V4L2_STD_UNKNOWN. When detection is not possible or fails,
the set must contain all standards supported by the current video input
or output.
[media] doc-rst: improve display of notes and warnings There are several notes and warning mesages in the middle of the media docbook. Use the ReST tags for that, as it makes them visually better and hightlights them. While here, modify a few ones to make them clearer. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-07-10 22:57:43 +08:00
.. note:: Drivers shall *not* switch the video standard
automatically if a new video standard is detected. Instead, drivers
should send the ``V4L2_EVENT_SOURCE_CHANGE`` event (if they support
this) and expect that userspace will take action by calling
:ref:`VIDIOC_QUERYSTD`. The reason is that a new video standard can mean
different buffer sizes as well, and you cannot change buffer sizes on
the fly. In general, applications that receive the Source Change event
will have to call :ref:`VIDIOC_QUERYSTD`, and if the detected video
standard is valid they will have to stop streaming, set the new
standard, allocate new buffers and start streaming again.
doc-rst: linux_tv DocBook to reST migration (docs-next) This is the restructuredText (reST) migration of the ``media`` DocBook-XML set from the linux_tv project. Signed-off-by: Markus Heiser <markus.heiser@darmarIT.de> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-06-30 21:18:56 +08:00
doc-rst: linux_tv: don't use uppercases for syscall sections On the syscall conversions, we used uppercase for the sections, but this is too bold. So, convert them to Camel Case, as it looks visually better. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-07-06 02:14:35 +08:00
Return Value
doc-rst: linux_tv DocBook to reST migration (docs-next) This is the restructuredText (reST) migration of the ``media`` DocBook-XML set from the linux_tv project. Signed-off-by: Markus Heiser <markus.heiser@darmarIT.de> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-06-30 21:18:56 +08:00
============
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.
ENODATA
Standard video timings are not supported for this input or output.