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+.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
+.. c:namespace:: V4L
+
+.. _VIDIOC_DV_TIMINGS_CAP:
+
+*********************************************************
+ioctl VIDIOC_DV_TIMINGS_CAP, VIDIOC_SUBDEV_DV_TIMINGS_CAP
+*********************************************************
+
+Name
+====
+
+VIDIOC_DV_TIMINGS_CAP - VIDIOC_SUBDEV_DV_TIMINGS_CAP - The capabilities of the Digital Video receiver/transmitter
+
+Synopsis
+========
+
+.. c:macro:: VIDIOC_DV_TIMINGS_CAP
+
+``int ioctl(int fd, VIDIOC_DV_TIMINGS_CAP, struct v4l2_dv_timings_cap *argp)``
+
+.. c:macro:: VIDIOC_SUBDEV_DV_TIMINGS_CAP
+
+``int ioctl(int fd, VIDIOC_SUBDEV_DV_TIMINGS_CAP, struct v4l2_dv_timings_cap *argp)``
+
+Arguments
+=========
+
+``fd``
+ File descriptor returned by :c:func:`open()`.
+
+``argp``
+ Pointer to struct :c:type:`v4l2_dv_timings_cap`.
+
+Description
+===========
+
+To query the capabilities of the DV receiver/transmitter applications
+initialize the ``pad`` field to 0, zero the reserved array of struct
+:c:type:`v4l2_dv_timings_cap` and call the
+``VIDIOC_DV_TIMINGS_CAP`` ioctl on a video node and the driver will fill
+in the structure.
+
+.. note::
+
+ Drivers may return different values after
+ switching the video input or output.
+
+When implemented by the driver DV capabilities of subdevices can be
+queried by calling the ``VIDIOC_SUBDEV_DV_TIMINGS_CAP`` ioctl directly
+on a subdevice node. The capabilities are specific to inputs (for DV
+receivers) or outputs (for DV transmitters), applications must specify
+the desired pad number in the struct
+:c:type:`v4l2_dv_timings_cap` ``pad`` field and
+zero the ``reserved`` array. Attempts to query capabilities on a pad
+that doesn't support them will return an ``EINVAL`` error code.
+
+.. tabularcolumns:: |p{1.2cm}|p{3.2cm}|p{12.9cm}|
+
+.. c:type:: v4l2_bt_timings_cap
+
+.. flat-table:: struct v4l2_bt_timings_cap
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 1 1 2
+
+ * - __u32
+ - ``min_width``
+ - Minimum width of the active video in pixels.
+ * - __u32
+ - ``max_width``
+ - Maximum width of the active video in pixels.
+ * - __u32
+ - ``min_height``
+ - Minimum height of the active video in lines.
+ * - __u32
+ - ``max_height``
+ - Maximum height of the active video in lines.
+ * - __u64
+ - ``min_pixelclock``
+ - Minimum pixelclock frequency in Hz.
+ * - __u64
+ - ``max_pixelclock``
+ - Maximum pixelclock frequency in Hz.
+ * - __u32
+ - ``standards``
+ - The video standard(s) supported by the hardware. See
+ :ref:`dv-bt-standards` for a list of standards.
+ * - __u32
+ - ``capabilities``
+ - Several flags giving more information about the capabilities. See
+ :ref:`dv-bt-cap-capabilities` for a description of the flags.
+ * - __u32
+ - ``reserved``\ [16]
+ - Reserved for future extensions.
+ Drivers must set the array to zero.
+
+
+.. tabularcolumns:: |p{4.4cm}|p{3.6cm}|p{9.3cm}|
+
+.. c:type:: v4l2_dv_timings_cap
+
+.. flat-table:: struct v4l2_dv_timings_cap
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 1 1 2
+
+ * - __u32
+ - ``type``
+ - Type of DV timings as listed in :ref:`dv-timing-types`.
+ * - __u32
+ - ``pad``
+ - Pad number as reported by the media controller API. This field is
+ only used when operating on a subdevice node. When operating on a
+ video node applications must set this field to zero.
+ * - __u32
+ - ``reserved``\ [2]
+ - Reserved for future extensions.
+
+ Drivers and applications must set the array to zero.
+ * - union {
+ - (anonymous)
+ * - struct :c:type:`v4l2_bt_timings_cap`
+ - ``bt``
+ - BT.656/1120 timings capabilities of the hardware.
+ * - __u32
+ - ``raw_data``\ [32]
+ * - }
+ -
+
+.. tabularcolumns:: |p{7.2cm}|p{10.3cm}|
+
+.. _dv-bt-cap-capabilities:
+
+.. flat-table:: DV BT Timing capabilities
+ :header-rows: 0
+ :stub-columns: 0
+
+ * - Flag
+ - Description
+ * -
+ -
+ * - ``V4L2_DV_BT_CAP_INTERLACED``
+ - Interlaced formats are supported.
+ * - ``V4L2_DV_BT_CAP_PROGRESSIVE``
+ - Progressive formats are supported.
+ * - ``V4L2_DV_BT_CAP_REDUCED_BLANKING``
+ - CVT/GTF specific: the timings can make use of reduced blanking
+ (CVT) or the 'Secondary GTF' curve (GTF).
+ * - ``V4L2_DV_BT_CAP_CUSTOM``
+ - Can support non-standard timings, i.e. timings not belonging to
+ the standards set in the ``standards`` field.
+
+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.