linux_dsm_epyc7002/Documentation/media/uapi/v4l/vidioc-g-frequency.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

105 lines
3.3 KiB
ReStructuredText

.. -*- coding: utf-8; mode: rst -*-
.. _VIDIOC_G_FREQUENCY:
********************************************
ioctl VIDIOC_G_FREQUENCY, VIDIOC_S_FREQUENCY
********************************************
Name
====
VIDIOC_G_FREQUENCY - VIDIOC_S_FREQUENCY - Get or set tuner or modulator radio frequency
Synopsis
========
.. c:function:: int ioctl( int fd, VIDIOC_G_FREQUENCY, struct v4l2_frequency *argp )
:name: VIDIOC_G_FREQUENCY
.. c:function:: int ioctl( int fd, VIDIOC_S_FREQUENCY, const struct v4l2_frequency *argp )
:name: VIDIOC_S_FREQUENCY
Arguments
=========
``fd``
File descriptor returned by :ref:`open() <func-open>`.
``argp``
Description
===========
To get the current tuner or modulator radio frequency applications set
the ``tuner`` field of a struct
:c:type:`v4l2_frequency` to the respective tuner or
modulator number (only input devices have tuners, only output devices
have modulators), zero out the ``reserved`` array and call the
:ref:`VIDIOC_G_FREQUENCY <VIDIOC_G_FREQUENCY>` ioctl with a pointer to this structure. The
driver stores the current frequency in the ``frequency`` field.
To change the current tuner or modulator radio frequency applications
initialize the ``tuner``, ``type`` and ``frequency`` fields, and the
``reserved`` array of a struct :c:type:`v4l2_frequency`
and call the :ref:`VIDIOC_S_FREQUENCY <VIDIOC_G_FREQUENCY>` ioctl with a pointer to this
structure. When the requested frequency is not possible the driver
assumes the closest possible value. However :ref:`VIDIOC_S_FREQUENCY <VIDIOC_G_FREQUENCY>` is a
write-only ioctl, it does not return the actual new frequency.
.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.7cm}|
.. c:type:: v4l2_frequency
.. flat-table:: struct v4l2_frequency
:header-rows: 0
:stub-columns: 0
:widths: 1 1 2
* - __u32
- ``tuner``
- The tuner or modulator index number. This is the same value as in
the struct :c:type:`v4l2_input` ``tuner`` field and
the struct :c:type:`v4l2_tuner` ``index`` field, or
the struct :c:type:`v4l2_output` ``modulator`` field
and the struct :c:type:`v4l2_modulator` ``index``
field.
* - __u32
- ``type``
- The tuner type. This is the same value as in the struct
:c:type:`v4l2_tuner` ``type`` field. The type must be
set to ``V4L2_TUNER_RADIO`` for ``/dev/radioX`` device nodes, and
to ``V4L2_TUNER_ANALOG_TV`` for all others. Set this field to
``V4L2_TUNER_RADIO`` for modulators (currently only radio
modulators are supported). See :c:type:`v4l2_tuner_type`
* - __u32
- ``frequency``
- Tuning frequency in units of 62.5 kHz, or if the struct
:c:type:`v4l2_tuner` or struct
:c:type:`v4l2_modulator` ``capability`` flag
``V4L2_TUNER_CAP_LOW`` is set, in units of 62.5 Hz. A 1 Hz unit is
used when the ``capability`` flag ``V4L2_TUNER_CAP_1HZ`` is set.
* - __u32
- ``reserved``\ [8]
- 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
The ``tuner`` index is out of bounds or the value in the ``type``
field is wrong.
EBUSY
A hardware seek is in progress.