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mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-22 20:23:57 +08:00
linux-next/Documentation/media/uapi/v4l/vidioc-g-audioout.rst
Laurent Pinchart c2b66cafdf [media] v4l: doc: Remove row numbers from tables
Shorten the tables by removing row numbers in comments, allowing for
later insertion of rows with minimal diffs.

All changes have been generated by the following script.

import io
import re
import sys

def process_table(fname, data):
	if fname.endswith('hist-v4l2.rst'):
		data = re.sub(u'\n{1,2}\t( ?)  -( ?) ?', u'\n\t\\1 -\\2', data, flags = re.MULTILINE)
		data = re.sub(u'\n(\t|       )-  \.\. row [0-9]+\n\t  ?-( ?) ?', u'\\1* -\\2', data, flags = re.MULTILINE)
	else:
		data = re.sub(u'\n{1,2}       -( ?) ?', u'\n      -\\1', data, flags = re.MULTILINE)
		data = re.sub(u'(\n?)(\n\n    -  \.\. row 1\n)', u'\n\\2', data, flags = re.MULTILINE)
		data = re.sub(u'\n    -  \.\. row [0-9]+\n      -( ?) ?', u'    * -\\1', data, flags = re.MULTILINE)
		data = re.sub(u'\n    -  \.\. row [0-9]+\n       \.\. (_[A-Z0-9_`-]*:)', u'\n    -  .. \\1', data, flags = re.MULTILINE)
		data = re.sub(u'\n    -  \.\. (_[A-Z0-9_`-]*:)\n      -', u'    * .. \\1\n\n      -', data, flags = re.MULTILINE)
		data = re.sub(u'^       - ', u'      -', data, flags = re.MULTILINE)
		data = re.sub(u'^(\t{1,2})  ', u'\\1', data, flags = re.MULTILINE)

	return data

def process_file(fname, data):
	buf = io.StringIO(data)
	output = ''
	in_table = False
	table_separator = 0

	for line in buf.readlines():
		if line.find('.. flat-table::') != -1:
			in_table = True
			table = ''
		elif in_table and not re.match('^[\t\n]|(    )', line):
			in_table = False
			output += process_table(fname, table)

		if in_table:
			table += line
		else:
			output += line

	if in_table:
		in_table = False
		output += process_table(fname, table)

	return output

fname = sys.argv[1]

data = file(fname, 'rb').read().decode('utf-8')
data = process_file(fname, data)
file(fname, 'wb').write(data.encode('utf-8'))

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2016-09-22 07:03:14 -03:00

101 lines
2.9 KiB
ReStructuredText

.. -*- coding: utf-8; mode: rst -*-
.. _VIDIOC_G_AUDOUT:
**************************************
ioctl VIDIOC_G_AUDOUT, VIDIOC_S_AUDOUT
**************************************
Name
====
VIDIOC_G_AUDOUT - VIDIOC_S_AUDOUT - Query or select the current audio output
Synopsis
========
.. c:function:: int ioctl( int fd, VIDIOC_G_AUDOUT, struct v4l2_audioout *argp )
:name: VIDIOC_G_AUDOUT
.. c:function:: int ioctl( int fd, VIDIOC_S_AUDOUT, const struct v4l2_audioout *argp )
:name: VIDIOC_S_AUDOUT
Arguments
=========
``fd``
File descriptor returned by :ref:`open() <func-open>`.
``argp``
Description
===========
To query the current audio output applications zero out the ``reserved``
array of a struct :c:type:`v4l2_audioout` and call the
``VIDIOC_G_AUDOUT`` 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
output.
Audio outputs have no writable properties. Nevertheless, to select the
current audio output applications can initialize the ``index`` field and
``reserved`` array (which in the future may contain writable properties)
of a struct :c:type:`v4l2_audioout` structure and call the
``VIDIOC_S_AUDOUT`` ioctl. Drivers switch to the requested output or
return the ``EINVAL`` error code when the index is out of bounds. This is a
write-only ioctl, it does not return the current audio output attributes
as ``VIDIOC_G_AUDOUT`` does.
.. note::
Connectors on a TV card to loop back the received audio signal
to a sound card are not audio outputs in this sense.
.. c:type:: v4l2_audioout
.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.7cm}|
.. flat-table:: struct v4l2_audioout
:header-rows: 0
:stub-columns: 0
:widths: 1 1 2
* - __u32
- ``index``
- Identifies the audio output, set by the driver or application.
* - __u8
- ``name``\ [32]
- Name of the audio output, a NUL-terminated ASCII string, for
example: "Line Out". This information is intended for the user,
preferably the connector label on the device itself.
* - __u32
- ``capability``
- Audio capability flags, none defined yet. Drivers must set this
field to zero.
* - __u32
- ``mode``
- Audio mode, none defined yet. Drivers and applications (on
``VIDIOC_S_AUDOUT``) must set this field to zero.
* - __u32
- ``reserved``\ [2]
- Reserved for future extensions. Drivers and applications must set
the array to zero.
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 outputs combine with the current video output, or the
number of the selected audio output is out of bounds or it does not
combine.