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1.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later2.. c:namespace:: V4L3 4.. _VIDIOC_ENUM_DV_TIMINGS:5 6***********************************************************7ioctl VIDIOC_ENUM_DV_TIMINGS, VIDIOC_SUBDEV_ENUM_DV_TIMINGS8***********************************************************9 10Name11====12 13VIDIOC_ENUM_DV_TIMINGS - VIDIOC_SUBDEV_ENUM_DV_TIMINGS - Enumerate supported Digital Video timings14 15Synopsis16========17 18.. c:macro:: VIDIOC_ENUM_DV_TIMINGS19 20``int ioctl(int fd, VIDIOC_ENUM_DV_TIMINGS, struct v4l2_enum_dv_timings *argp)``21 22.. c:macro:: VIDIOC_SUBDEV_ENUM_DV_TIMINGS23 24``int ioctl(int fd, VIDIOC_SUBDEV_ENUM_DV_TIMINGS, struct v4l2_enum_dv_timings *argp)``25 26Arguments27=========28 29``fd``30 File descriptor returned by :c:func:`open()`.31 32``argp``33 Pointer to struct :c:type:`v4l2_enum_dv_timings`.34 35Description36===========37 38While some DV receivers or transmitters support a wide range of timings,39others support only a limited number of timings. With this ioctl40applications can enumerate a list of known supported timings. Call41:ref:`VIDIOC_DV_TIMINGS_CAP` to check if it42also supports other standards or even custom timings that are not in43this list.44 45To query the available timings, applications initialize the ``index``46field, set the ``pad`` field to 0, zero the reserved array of struct47:c:type:`v4l2_enum_dv_timings` and call the48``VIDIOC_ENUM_DV_TIMINGS`` ioctl on a video node with a pointer to this49structure. Drivers fill the rest of the structure or return an ``EINVAL``50error code when the index is out of bounds. To enumerate all supported51DV timings, applications shall begin at index zero, incrementing by one52until the driver returns ``EINVAL``.53 54.. note::55 56 Drivers may enumerate a different set of DV timings after57 switching the video input or output.58 59When implemented by the driver DV timings of subdevices can be queried60by calling the ``VIDIOC_SUBDEV_ENUM_DV_TIMINGS`` ioctl directly on a61subdevice node. The DV timings are specific to inputs (for DV receivers)62or outputs (for DV transmitters), applications must specify the desired63pad number in the struct64:c:type:`v4l2_enum_dv_timings` ``pad`` field.65Attempts to enumerate timings on a pad that doesn't support them will66return an ``EINVAL`` error code.67 68.. c:type:: v4l2_enum_dv_timings69 70.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.5cm}|71 72.. flat-table:: struct v4l2_enum_dv_timings73 :header-rows: 074 :stub-columns: 075 :widths: 1 1 276 77 * - __u3278 - ``index``79 - Number of the DV timings, set by the application.80 * - __u3281 - ``pad``82 - Pad number as reported by the media controller API. This field is83 only used when operating on a subdevice node. When operating on a84 video node applications must set this field to zero.85 * - __u3286 - ``reserved``\ [2]87 - Reserved for future extensions. Drivers and applications must set88 the array to zero.89 * - struct :c:type:`v4l2_dv_timings`90 - ``timings``91 - The timings.92 93Return Value94============95 96On success 0 is returned, on error -1 and the ``errno`` variable is set97appropriately. The generic error codes are described at the98:ref:`Generic Error Codes <gen-errors>` chapter.99 100EINVAL101 The struct :c:type:`v4l2_enum_dv_timings`102 ``index`` is out of bounds or the ``pad`` number is invalid.103 104ENODATA105 Digital video presets are not supported for this input or output.106