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linux_old1/Documentation/media/uapi/mediactl/media-ioc-setup-link.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 -*-
.. _media-ioc-setup-link:
**************************
ioctl MEDIA_IOC_SETUP_LINK
**************************
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
MEDIA_IOC_SETUP_LINK - Modify the properties of a link
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, struct media_link_desc *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() <media-func-open>`.
``request``
MEDIA_IOC_SETUP_LINK
``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
===========
To change link properties applications fill a struct
:ref:`media_link_desc <media-link-desc>` with link identification
information (source and sink pad) and the new requested link flags. They
then call the MEDIA_IOC_SETUP_LINK ioctl with a pointer to that
structure.
The only configurable property is the ``ENABLED`` link flag to
enable/disable a link. Links marked with the ``IMMUTABLE`` link flag can
not be enabled or disabled.
Link configuration has no side effect on other links. If an enabled link
at the sink pad prevents the link from being enabled, the driver returns
doc-rst: linux_tv: Error codes should be const All error codes should be const. Most are, but there are lots of places where we forgot to add <constant> at the DocBook. Fix those via this small script: for i in $(git grep -lE "\s+E[A-Z]+\b" Documentation/linux_tv/); do perl -ne 's,([^\`])\b(E[A-Z]+)\b,\1``\2``,g; print $_' <$i >a && mv a $i; done As there are false positives, we needed to merge only the changes that make sense, skipping the c blocks and skipping things like EDID, EN, ETS that were also converted by the above code. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-07-03 22:53:09 +08:00
with an ``EBUSY`` error code.
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
Only links marked with the ``DYNAMIC`` link flag can be enabled/disabled
while streaming media data. Attempting to enable or disable a streaming
doc-rst: linux_tv: Error codes should be const All error codes should be const. Most are, but there are lots of places where we forgot to add <constant> at the DocBook. Fix those via this small script: for i in $(git grep -lE "\s+E[A-Z]+\b" Documentation/linux_tv/); do perl -ne 's,([^\`])\b(E[A-Z]+)\b,\1``\2``,g; print $_' <$i >a && mv a $i; done As there are false positives, we needed to merge only the changes that make sense, skipping the c blocks and skipping things like EDID, EN, ETS that were also converted by the above code. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-07-03 22:53:09 +08:00
non-dynamic link will return an ``EBUSY`` error code.
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: Error codes should be const All error codes should be const. Most are, but there are lots of places where we forgot to add <constant> at the DocBook. Fix those via this small script: for i in $(git grep -lE "\s+E[A-Z]+\b" Documentation/linux_tv/); do perl -ne 's,([^\`])\b(E[A-Z]+)\b,\1``\2``,g; print $_' <$i >a && mv a $i; done As there are false positives, we needed to merge only the changes that make sense, skipping the c blocks and skipping things like EDID, EN, ETS that were also converted by the above code. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-07-03 22:53:09 +08:00
If the specified link can't be found the driver returns with an ``EINVAL``
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
error code.
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.
EINVAL
The struct :ref:`media_link_desc <media-link-desc>` references a
non-existing link, or the link is immutable and an attempt to modify
its configuration was made.