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+.. Permission is granted to copy, distribute and/or modify this
+.. document under the terms of the GNU Free Documentation License,
+.. Version 1.1 or any later version published by the Free Software
+.. Foundation, with no Invariant Sections, no Front-Cover Texts
+.. and no Back-Cover Texts. A copy of the license is included at
+.. Documentation/userspace-api/media/fdl-appendix.rst.
+..
+.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections
+
+.. _VIDIOC_SUBDEV_ENUM_FRAME_SIZE:
+
+***********************************
+ioctl VIDIOC_SUBDEV_ENUM_FRAME_SIZE
+***********************************
+
+Name
+====
+
+VIDIOC_SUBDEV_ENUM_FRAME_SIZE - Enumerate media bus frame sizes
+
+
+Synopsis
+========
+
+.. c:function:: int ioctl( int fd, VIDIOC_SUBDEV_ENUM_FRAME_SIZE, struct v4l2_subdev_frame_size_enum * argp )
+ :name: VIDIOC_SUBDEV_ENUM_FRAME_SIZE
+
+
+Arguments
+=========
+
+``fd``
+ File descriptor returned by :ref:`open() <func-open>`.
+
+``argp``
+ Pointer to struct :c:type:`v4l2_subdev_frame_size_enum`.
+
+
+Description
+===========
+
+This ioctl allows applications to enumerate all frame sizes supported by
+a sub-device on the given pad for the given media bus format. Supported
+formats can be retrieved with the
+:ref:`VIDIOC_SUBDEV_ENUM_MBUS_CODE`
+ioctl.
+
+To enumerate frame sizes applications initialize the ``pad``, ``which``
+, ``code`` and ``index`` fields of the struct
+:c:type:`v4l2_subdev_mbus_code_enum` and
+call the :ref:`VIDIOC_SUBDEV_ENUM_FRAME_SIZE` ioctl with a pointer to the
+structure. Drivers fill the minimum and maximum frame sizes or return an
+EINVAL error code if one of the input parameters is invalid.
+
+Sub-devices that only support discrete frame sizes (such as most
+sensors) will return one or more frame sizes with identical minimum and
+maximum values.
+
+Not all possible sizes in given [minimum, maximum] ranges need to be
+supported. For instance, a scaler that uses a fixed-point scaling ratio
+might not be able to produce every frame size between the minimum and
+maximum values. Applications must use the
+:ref:`VIDIOC_SUBDEV_S_FMT <VIDIOC_SUBDEV_G_FMT>` ioctl to try the
+sub-device for an exact supported frame size.
+
+Available frame sizes may depend on the current 'try' formats at other
+pads of the sub-device, as well as on the current active links and the
+current values of V4L2 controls. See
+:ref:`VIDIOC_SUBDEV_G_FMT` for more
+information about try formats.
+
+
+.. c:type:: v4l2_subdev_frame_size_enum
+
+.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.7cm}|
+
+.. flat-table:: struct v4l2_subdev_frame_size_enum
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 1 1 2
+
+ * - __u32
+ - ``index``
+ - Number of the format in the enumeration, set by the application.
+ * - __u32
+ - ``pad``
+ - Pad number as reported by the media controller API.
+ * - __u32
+ - ``code``
+ - The media bus format code, as defined in
+ :ref:`v4l2-mbus-format`.
+ * - __u32
+ - ``min_width``
+ - Minimum frame width, in pixels.
+ * - __u32
+ - ``max_width``
+ - Maximum frame width, in pixels.
+ * - __u32
+ - ``min_height``
+ - Minimum frame height, in pixels.
+ * - __u32
+ - ``max_height``
+ - Maximum frame height, in pixels.
+ * - __u32
+ - ``which``
+ - Frame sizes to be enumerated, from enum
+ :ref:`v4l2_subdev_format_whence <v4l2-subdev-format-whence>`.
+ * - __u32
+ - ``reserved``\ [8]
+ - Reserved for future extensions. Applications and drivers must set
+ the array to zero.
+
+
+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_subdev_frame_size_enum`
+ ``pad`` references a non-existing pad, the ``code`` is invalid for
+ the given pad or the ``index`` field is out of bounds.