1 files changed, 105 insertions, 0 deletions
diff --git a/Documentation/userspace-api/media/v4l/vidioc-enum-dv-timings.rst b/Documentation/userspace-api/media/v4l/vidioc-enum-dv-timings.rst
new file mode 100644
index 000000000..a91c1a3f0
--- /dev/null
+++ b/Documentation/userspace-api/media/v4l/vidioc-enum-dv-timings.rst
@@ -0,0 +1,105 @@
+.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
+.. c:namespace:: V4L
+
+.. _VIDIOC_ENUM_DV_TIMINGS:
+
+***********************************************************
+ioctl VIDIOC_ENUM_DV_TIMINGS, VIDIOC_SUBDEV_ENUM_DV_TIMINGS
+***********************************************************
+
+Name
+====
+
+VIDIOC_ENUM_DV_TIMINGS - VIDIOC_SUBDEV_ENUM_DV_TIMINGS - Enumerate supported Digital Video timings
+
+Synopsis
+========
+
+.. c:macro:: VIDIOC_ENUM_DV_TIMINGS
+
+``int ioctl(int fd, VIDIOC_ENUM_DV_TIMINGS, struct v4l2_enum_dv_timings *argp)``
+
+.. c:macro:: VIDIOC_SUBDEV_ENUM_DV_TIMINGS
+
+``int ioctl(int fd, VIDIOC_SUBDEV_ENUM_DV_TIMINGS, struct v4l2_enum_dv_timings *argp)``
+
+Arguments
+=========
+
+``fd``
+    File descriptor returned by :c:func:`open()`.
+
+``argp``
+    Pointer to struct :c:type:`v4l2_enum_dv_timings`.
+
+Description
+===========
+
+While some DV receivers or transmitters support a wide range of timings,
+others support only a limited number of timings. With this ioctl
+applications can enumerate a list of known supported timings. Call
+:ref:`VIDIOC_DV_TIMINGS_CAP` to check if it
+also supports other standards or even custom timings that are not in
+this list.
+
+To query the available timings, applications initialize the ``index``
+field, set the ``pad`` field to 0, zero the reserved array of struct
+:c:type:`v4l2_enum_dv_timings` and call the
+``VIDIOC_ENUM_DV_TIMINGS`` ioctl on a video node 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 supported
+DV timings, applications shall begin at index zero, incrementing by one
+until the driver returns ``EINVAL``.
+
+.. note::
+
+   Drivers may enumerate a different set of DV timings after
+   switching the video input or output.
+
+When implemented by the driver DV timings of subdevices can be queried
+by calling the ``VIDIOC_SUBDEV_ENUM_DV_TIMINGS`` ioctl directly on a
+subdevice node. The DV timings 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_enum_dv_timings` ``pad`` field.
+Attempts to enumerate timings on a pad that doesn't support them will
+return an ``EINVAL`` error code.
+
+.. c:type:: v4l2_enum_dv_timings
+
+.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.5cm}|
+
+.. flat-table:: struct v4l2_enum_dv_timings
+    :header-rows:  0
+    :stub-columns: 0
+    :widths:       1 1 2
+
+    * - __u32
+      - ``index``
+      - Number of the DV timings, set by the application.
+    * - __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.
+    * - struct :c:type:`v4l2_dv_timings`
+      - ``timings``
+      - The timings.
+
+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_enum_dv_timings`
+    ``index`` is out of bounds or the ``pad`` number is invalid.
+
+ENODATA
+    Digital video presets are not supported for this input or output.