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+.. -*- coding: utf-8; mode: rst -*-
+
+.. _VIDIOC_ENUMINPUT:
+
+**********************
+ioctl VIDIOC_ENUMINPUT
+**********************
+
+Name
+====
+
+VIDIOC_ENUMINPUT - Enumerate video inputs
+
+
+Synopsis
+========
+
+.. cpp:function:: int ioctl( int fd, int request, struct v4l2_input *argp )
+
+
+Arguments
+=========
+
+``fd``
+ File descriptor returned by :ref:`open() <func-open>`.
+
+``request``
+ VIDIOC_ENUMINPUT
+
+``argp``
+
+
+Description
+===========
+
+To query the attributes of a video input applications initialize the
+``index`` field of struct :ref:`v4l2_input <v4l2-input>` and call 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``.
+
+
+.. _v4l2-input:
+
+.. flat-table:: struct v4l2_input
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 1 1 2
+
+
+ - .. row 1
+
+ - __u32
+
+ - ``index``
+
+ - Identifies the input, set by the application.
+
+ - .. row 2
+
+ - __u8
+
+ - ``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.
+
+ - .. row 3
+
+ - __u32
+
+ - ``type``
+
+ - Type of the input, see :ref:`input-type`.
+
+ - .. row 4
+
+ - __u32
+
+ - ``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.
+
+ 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`.
+
+ - .. row 5
+
+ - __u32
+
+ - ``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`.
+
+ - .. row 6
+
+ - :ref:`v4l2_std_id <v4l2-std-id>`
+
+ - ``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`.
+
+ - .. row 7
+
+ - __u32
+
+ - ``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.
+
+ - .. row 8
+
+ - __u32
+
+ - ``capabilities``
+
+ - This field provides capabilities for the input. See
+ :ref:`input-capabilities` for flags.
+
+ - .. row 9
+
+ - __u32
+
+ - ``reserved``\ [3]
+
+ - Reserved for future extensions. Drivers must set the array to
+ zero.
+
+
+
+.. _input-type:
+
+.. flat-table:: Input Types
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 3 1 4
+
+
+ - .. row 1
+
+ - ``V4L2_INPUT_TYPE_TUNER``
+
+ - 1
+
+ - This input uses a tuner (RF demodulator).
+
+ - .. row 2
+
+ - ``V4L2_INPUT_TYPE_CAMERA``
+
+ - 2
+
+ - Analog baseband input, for example CVBS / Composite Video,
+ S-Video, RGB.
+
+
+
+.. _input-status:
+
+.. flat-table:: Input Status Flags
+ :header-rows: 0
+ :stub-columns: 0
+
+
+ - .. row 1
+
+ - :cspan:`2` General
+
+ - .. row 2
+
+ - ``V4L2_IN_ST_NO_POWER``
+
+ - 0x00000001
+
+ - Attached device is off.
+
+ - .. row 3
+
+ - ``V4L2_IN_ST_NO_SIGNAL``
+
+ - 0x00000002
+
+ -
+
+ - .. row 4
+
+ - ``V4L2_IN_ST_NO_COLOR``
+
+ - 0x00000004
+
+ - The hardware supports color decoding, but does not detect color
+ modulation in the signal.
+
+ - .. row 5
+
+ - :cspan:`2` Sensor Orientation
+
+ - .. row 6
+
+ - ``V4L2_IN_ST_HFLIP``
+
+ - 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.
+
+ - .. row 7
+
+ - ``V4L2_IN_ST_VFLIP``
+
+ - 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:: A 180 degree rotation is the same as HFLIP | VFLIP
+
+ - .. row 8
+
+ - :cspan:`2` Analog Video
+
+ - .. row 9
+
+ - ``V4L2_IN_ST_NO_H_LOCK``
+
+ - 0x00000100
+
+ - No horizontal sync lock.
+
+ - .. row 10
+
+ - ``V4L2_IN_ST_COLOR_KILL``
+
+ - 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.
+
+ - .. row 11
+
+ - :cspan:`2` Digital Video
+
+ - .. row 12
+
+ - ``V4L2_IN_ST_NO_SYNC``
+
+ - 0x00010000
+
+ - No synchronization lock.
+
+ - .. row 13
+
+ - ``V4L2_IN_ST_NO_EQU``
+
+ - 0x00020000
+
+ - No equalizer lock.
+
+ - .. row 14
+
+ - ``V4L2_IN_ST_NO_CARRIER``
+
+ - 0x00040000
+
+ - Carrier recovery failed.
+
+ - .. row 15
+
+ - :cspan:`2` VCR and Set-Top Box
+
+ - .. row 16
+
+ - ``V4L2_IN_ST_MACROVISION``
+
+ - 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.
+
+ - .. row 17
+
+ - ``V4L2_IN_ST_NO_ACCESS``
+
+ - 0x02000000
+
+ - Conditional access denied.
+
+ - .. row 18
+
+ - ``V4L2_IN_ST_VTR``
+
+ - 0x04000000
+
+ - VTR time constant. [?]
+
+
+
+.. _input-capabilities:
+
+.. flat-table:: Input capabilities
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 3 1 4
+
+
+ - .. row 1
+
+ - ``V4L2_IN_CAP_DV_TIMINGS``
+
+ - 0x00000002
+
+ - This input supports setting video timings by using
+ VIDIOC_S_DV_TIMINGS.
+
+ - .. row 2
+
+ - ``V4L2_IN_CAP_STD``
+
+ - 0x00000004
+
+ - This input supports setting the TV standard by using
+ VIDIOC_S_STD.
+
+ - .. row 3
+
+ - ``V4L2_IN_CAP_NATIVE_SIZE``
+
+ - 0x00000008
+
+ - This input supports setting the native size using the
+ ``V4L2_SEL_TGT_NATIVE_SIZE`` selection target, see
+ :ref:`v4l2-selections-common`.
+
+
+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 struct :ref:`v4l2_input <v4l2-input>` ``index`` is out of
+ bounds.