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+.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
+.. c:namespace:: V4L
+
+.. _VIDIOC_ENUMINPUT:
+
+**********************
+ioctl VIDIOC_ENUMINPUT
+**********************
+
+Name
+====
+
+VIDIOC_ENUMINPUT - Enumerate video inputs
+
+Synopsis
+========
+
+.. c:macro:: VIDIOC_ENUMINPUT
+
+``int ioctl(int fd, VIDIOC_ENUMINPUT, struct v4l2_input *argp)``
+
+Arguments
+=========
+
+``fd``
+ File descriptor returned by :c:func:`open()`.
+
+``argp``
+ Pointer to struct :c:type:`v4l2_input`.
+
+Description
+===========
+
+To query the attributes of a video input applications initialize the
+``index`` field of struct :c:type:`v4l2_input` and call the
+:ref:`VIDIOC_ENUMINPUT` 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``.
+
+.. tabularcolumns:: |p{3.0cm}|p{3.5cm}|p{10.8cm}|
+
+.. c:type:: v4l2_input
+
+.. flat-table:: struct v4l2_input
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 1 1 2
+
+ * - __u32
+ - ``index``
+ - Identifies the input, set by the application.
+ * - __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.
+ * - __u32
+ - ``type``
+ - Type of the input, see :ref:`input-type`.
+ * - __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`.
+ * - __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 :c:type:`v4l2_tuner` field ``index``. For
+ details on tuners see :ref:`tuner`.
+ * - :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`.
+ * - __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.
+ * - __u32
+ - ``capabilities``
+ - This field provides capabilities for the input. See
+ :ref:`input-capabilities` for flags.
+ * - __u32
+ - ``reserved``\ [3]
+ - Reserved for future extensions. Drivers must set the array to
+ zero.
+
+
+.. tabularcolumns:: |p{6.6cm}|p{1.0cm}|p{9.7cm}|
+
+.. _input-type:
+
+.. flat-table:: Input Types
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 3 1 4
+
+ * - ``V4L2_INPUT_TYPE_TUNER``
+ - 1
+ - This input uses a tuner (RF demodulator).
+ * - ``V4L2_INPUT_TYPE_CAMERA``
+ - 2
+ - Any non-tuner video input, for example Composite Video,
+ S-Video, HDMI, camera sensor. The naming as ``_TYPE_CAMERA`` is historical,
+ today we would have called it ``_TYPE_VIDEO``.
+ * - ``V4L2_INPUT_TYPE_TOUCH``
+ - 3
+ - This input is a touch device for capturing raw touch data.
+
+
+.. tabularcolumns:: |p{5.6cm}|p{2.6cm}|p{9.1cm}|
+
+.. _input-status:
+
+.. flat-table:: Input Status Flags
+ :header-rows: 0
+ :stub-columns: 0
+
+ * - :cspan:`2` General
+ * - ``V4L2_IN_ST_NO_POWER``
+ - 0x00000001
+ - Attached device is off.
+ * - ``V4L2_IN_ST_NO_SIGNAL``
+ - 0x00000002
+ -
+ * - ``V4L2_IN_ST_NO_COLOR``
+ - 0x00000004
+ - The hardware supports color decoding, but does not detect color
+ modulation in the signal.
+ * - :cspan:`2` Sensor Orientation
+ * - ``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.
+ * - ``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
+ * - :cspan:`2` Analog Video
+ * - ``V4L2_IN_ST_NO_H_LOCK``
+ - 0x00000100
+ - No horizontal sync lock.
+ * - ``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.
+ * - ``V4L2_IN_ST_NO_V_LOCK``
+ - 0x00000400
+ - No vertical sync lock.
+ * - ``V4L2_IN_ST_NO_STD_LOCK``
+ - 0x00000800
+ - No standard format lock in case of auto-detection format
+ by the component.
+ * - :cspan:`2` Digital Video
+ * - ``V4L2_IN_ST_NO_SYNC``
+ - 0x00010000
+ - No synchronization lock.
+ * - ``V4L2_IN_ST_NO_EQU``
+ - 0x00020000
+ - No equalizer lock.
+ * - ``V4L2_IN_ST_NO_CARRIER``
+ - 0x00040000
+ - Carrier recovery failed.
+ * - :cspan:`2` VCR and Set-Top Box
+ * - ``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.
+ * - ``V4L2_IN_ST_NO_ACCESS``
+ - 0x02000000
+ - Conditional access denied.
+ * - ``V4L2_IN_ST_VTR``
+ - 0x04000000
+ - VTR time constant. [?]
+
+
+.. tabularcolumns:: |p{6.6cm}|p{2.4cm}|p{8.3cm}|
+
+.. _input-capabilities:
+
+.. flat-table:: Input capabilities
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 3 1 4
+
+ * - ``V4L2_IN_CAP_DV_TIMINGS``
+ - 0x00000002
+ - This input supports setting video timings by using
+ ``VIDIOC_S_DV_TIMINGS``.
+ * - ``V4L2_IN_CAP_STD``
+ - 0x00000004
+ - This input supports setting the TV standard by using
+ ``VIDIOC_S_STD``.
+ * - ``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 :c:type:`v4l2_input` ``index`` is out of
+ bounds.