ioctl VIDIOC_ENUMINPUT
**********************
-*man VIDIOC_ENUMINPUT(2)*
+NAME
+====
-Enumerate video inputs
+VIDIOC_ENUMINPUT - Enumerate video inputs
-
-Synopsis
+SYNOPSIS
========
-.. c:function:: int ioctl( int fd, int request, struct v4l2_input *argp )
+.. cpp:function:: int ioctl( int fd, int request, struct v4l2_input *argp )
+
-Arguments
+ARGUMENTS
=========
``fd``
``argp``
-Description
+DESCRIPTION
===========
To query the attributes of a video input applications initialize the
``index`` field of struct :ref:`v4l2_input <v4l2-input>` and call the
-``VIDIOC_ENUMINPUT`` ioctl with a pointer to this structure. Drivers
-fill the rest of the structure or return an EINVAL error code when the
+:ref:`VIDIOC_ENUMINPUT` ioctl with a pointer to this structure. Drivers
+fill the rest of the structure or return an ``EINVAL`` error code when the
index is out of bounds. To enumerate all inputs applications shall begin
-at index zero, incrementing by one until the driver returns EINVAL.
+at index zero, incrementing by one until the driver returns ``EINVAL``.
.. _v4l2-input:
- ``name``\ [32]
- Name of the video input, a NUL-terminated ASCII string, for
- example: "Vin (Composite 2)". This information is intended for the
- user, preferably the connector label on the device itself.
+ example: "Vin (Composite 2)". This information is intended for the
+ user, preferably the connector label on the device itself.
- .. row 3
- ``audioset``
- Drivers can enumerate up to 32 video and audio inputs. This field
- shows which audio inputs were selectable as audio source if this
- was the currently selected video input. It is a bit mask. The LSB
- corresponds to audio input 0, the MSB to input 31. Any number of
- bits can be set, or none.
+ shows which audio inputs were selectable as audio source if this
+ was the currently selected video input. It is a bit mask. The LSB
+ corresponds to audio input 0, the MSB to input 31. Any number of
+ bits can be set, or none.
- When the driver does not enumerate audio inputs no bits must be
- set. Applications shall not interpret this as lack of audio
- support. Some drivers automatically select audio sources and do
- not enumerate them since there is no choice anyway.
+ When the driver does not enumerate audio inputs no bits must be
+ set. Applications shall not interpret this as lack of audio
+ support. Some drivers automatically select audio sources and do
+ not enumerate them since there is no choice anyway.
- For details on audio inputs and how to select the current input
- see :ref:`audio`.
+ For details on audio inputs and how to select the current input
+ see :ref:`audio`.
- .. row 5
- ``tuner``
- Capture devices can have zero or more tuners (RF demodulators).
- When the ``type`` is set to ``V4L2_INPUT_TYPE_TUNER`` this is an
- RF connector and this field identifies the tuner. It corresponds
- to struct :ref:`v4l2_tuner <v4l2-tuner>` field ``index``. For
- details on tuners see :ref:`tuner`.
+ When the ``type`` is set to ``V4L2_INPUT_TYPE_TUNER`` this is an
+ RF connector and this field identifies the tuner. It corresponds
+ to struct :ref:`v4l2_tuner <v4l2-tuner>` field ``index``. For
+ details on tuners see :ref:`tuner`.
- .. row 6
- ``std``
- Every video input supports one or more different video standards.
- This field is a set of all supported standards. For details on
- video standards and how to switch see :ref:`standard`.
+ This field is a set of all supported standards. For details on
+ video standards and how to switch see :ref:`standard`.
- .. row 7
- ``status``
- This field provides status information about the input. See
- :ref:`input-status` for flags. With the exception of the sensor
- orientation bits ``status`` is only valid when this is the current
- input.
+ :ref:`input-status` for flags. With the exception of the sensor
+ orientation bits ``status`` is only valid when this is the current
+ input.
- .. row 8
- ``capabilities``
- This field provides capabilities for the input. See
- :ref:`input-capabilities` for flags.
+ :ref:`input-capabilities` for flags.
- .. row 9
- ``reserved``\ [3]
- Reserved for future extensions. Drivers must set the array to
- zero.
+ zero.
- 2
- Analog baseband input, for example CVBS / Composite Video,
- S-Video, RGB.
+ S-Video, RGB.
- 0x00000002
- -
+ -
- .. row 4
- 0x00000004
- The hardware supports color decoding, but does not detect color
- modulation in the signal.
+ modulation in the signal.
- .. row 5
- 0x00000010
- The input is connected to a device that produces a signal that is
- flipped horizontally and does not correct this before passing the
- signal to userspace.
+ flipped horizontally and does not correct this before passing the
+ signal to userspace.
- .. row 7
- 0x00000020
- The input is connected to a device that produces a signal that is
- flipped vertically and does not correct this before passing the
- signal to userspace. Note that a 180 degree rotation is the same
- as HFLIP | VFLIP
+ flipped vertically and does not correct this before passing the
+ signal to userspace. Note that a 180 degree rotation is the same
+ as HFLIP | VFLIP
- .. row 8
- 0x00000200
- A color killer circuit automatically disables color decoding when
- it detects no color modulation. When this flag is set the color
- killer is enabled *and* has shut off color decoding.
+ it detects no color modulation. When this flag is set the color
+ killer is enabled *and* has shut off color decoding.
- .. row 11
- 0x01000000
- Macrovision is an analog copy prevention system mangling the video
- signal to confuse video recorders. When this flag is set
- Macrovision has been detected.
+ signal to confuse video recorders. When this flag is set
+ Macrovision has been detected.
- .. row 17
- 0x00000002
- This input supports setting video timings by using
- VIDIOC_S_DV_TIMINGS.
+ VIDIOC_S_DV_TIMINGS.
- .. row 2
- 0x00000004
- This input supports setting the TV standard by using
- VIDIOC_S_STD.
+ VIDIOC_S_STD.
- .. row 3
- 0x00000008
- This input supports setting the native size using the
- ``V4L2_SEL_TGT_NATIVE_SIZE`` selection target, see
- :ref:`v4l2-selections-common`.
-
+ ``V4L2_SEL_TGT_NATIVE_SIZE`` selection target, see
+ :ref:`v4l2-selections-common`.
-Return Value
+RETURN VALUE
============
On success 0 is returned, on error -1 and the ``errno`` variable is set
EINVAL
The struct :ref:`v4l2_input <v4l2-input>` ``index`` is out of
bounds.
-
-
-.. ------------------------------------------------------------------------------
-.. This file was automatically converted from DocBook-XML with the dbxml
-.. library (https://github.com/return42/sphkerneldoc). The origin XML comes
-.. from the linux kernel, refer to:
-..
-.. * https://github.com/torvalds/linux/tree/master/Documentation/DocBook
-.. ------------------------------------------------------------------------------
projects / deliverable / linux.git / blobdiff