mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2025-01-24 01:09:52 +07:00
fa92b04d98
Sphinx is really pedantic with respect to the order where table tags and references are created. Putting things at the wrong order causes troubles. The order that seems to work is: .. raw:: latex .. tabularcolumns:: .. _foo_name: .. cssclass: longtable .. flat-table:: Reorder the tags to the above order, to avoid troubles, and fix remaining warnings introduced by media recent patches. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
126 lines
3.5 KiB
ReStructuredText
126 lines
3.5 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
|
|
========
|
|
|
|
.. cpp:function:: int ioctl( int fd, int request, struct v4l2_frequency *argp )
|
|
|
|
.. cpp:function:: int ioctl( int fd, int request, const struct v4l2_frequency *argp )
|
|
|
|
|
|
Arguments
|
|
=========
|
|
|
|
``fd``
|
|
File descriptor returned by :ref:`open() <func-open>`.
|
|
|
|
``request``
|
|
VIDIOC_G_FREQUENCY, VIDIOC_S_FREQUENCY
|
|
|
|
``argp``
|
|
|
|
|
|
Description
|
|
===========
|
|
|
|
To get the current tuner or modulator radio frequency applications set
|
|
the ``tuner`` field of a struct
|
|
:ref:`v4l2_frequency <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 :ref:`v4l2_frequency <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}|
|
|
|
|
.. _v4l2-frequency:
|
|
|
|
.. flat-table:: struct v4l2_frequency
|
|
:header-rows: 0
|
|
:stub-columns: 0
|
|
:widths: 1 1 2
|
|
|
|
|
|
- .. row 1
|
|
|
|
- __u32
|
|
|
|
- ``tuner``
|
|
|
|
- The tuner or modulator index number. This is the same value as in
|
|
the struct :ref:`v4l2_input <v4l2-input>` ``tuner`` field and
|
|
the struct :ref:`v4l2_tuner <v4l2-tuner>` ``index`` field, or
|
|
the struct :ref:`v4l2_output <v4l2-output>` ``modulator`` field
|
|
and the struct :ref:`v4l2_modulator <v4l2-modulator>` ``index``
|
|
field.
|
|
|
|
- .. row 2
|
|
|
|
- __u32
|
|
|
|
- ``type``
|
|
|
|
- The tuner type. This is the same value as in the struct
|
|
:ref:`v4l2_tuner <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 :ref:`v4l2-tuner-type`
|
|
|
|
- .. row 3
|
|
|
|
- __u32
|
|
|
|
- ``frequency``
|
|
|
|
- Tuning frequency in units of 62.5 kHz, or if the struct
|
|
:ref:`v4l2_tuner <v4l2-tuner>` or struct
|
|
:ref:`v4l2_modulator <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.
|
|
|
|
- .. row 4
|
|
|
|
- __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.
|