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+.. -*- coding: utf-8; mode: rst -*-
+
+.. _VIDIOC_SUBDEV_ENUM_FRAME_SIZE:
+
+***********************************
+ioctl VIDIOC_SUBDEV_ENUM_FRAME_SIZE
+***********************************
+
+Name
+====
+
+VIDIOC_SUBDEV_ENUM_FRAME_SIZE - Enumerate media bus frame sizes
+
+
+Synopsis
+========
+
+.. cpp:function:: int ioctl( int fd, int request, struct v4l2_subdev_frame_size_enum * argp )
+
+
+Arguments
+=========
+
+``fd``
+    File descriptor returned by :ref:`open() <func-open>`.
+
+``request``
+    VIDIOC_SUBDEV_ENUM_FRAME_SIZE
+
+``argp``
+
+
+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
+:ref:`v4l2_subdev_mbus_code_enum <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.
+
+
+.. _v4l2-subdev-frame-size-enum:
+
+.. flat-table:: struct v4l2_subdev_frame_size_enum
+    :header-rows:  0
+    :stub-columns: 0
+    :widths:       1 1 2
+
+
+    -  .. row 1
+
+       -  __u32
+
+       -  ``index``
+
+       -  Number of the format in the enumeration, set by the application.
+
+    -  .. row 2
+
+       -  __u32
+
+       -  ``pad``
+
+       -  Pad number as reported by the media controller API.
+
+    -  .. row 3
+
+       -  __u32
+
+       -  ``code``
+
+       -  The media bus format code, as defined in
+	  :ref:`v4l2-mbus-format`.
+
+    -  .. row 4
+
+       -  __u32
+
+       -  ``min_width``
+
+       -  Minimum frame width, in pixels.
+
+    -  .. row 5
+
+       -  __u32
+
+       -  ``max_width``
+
+       -  Maximum frame width, in pixels.
+
+    -  .. row 6
+
+       -  __u32
+
+       -  ``min_height``
+
+       -  Minimum frame height, in pixels.
+
+    -  .. row 7
+
+       -  __u32
+
+       -  ``max_height``
+
+       -  Maximum frame height, in pixels.
+
+    -  .. row 8
+
+       -  __u32
+
+       -  ``which``
+
+       -  Frame sizes to be enumerated, from enum
+	  :ref:`v4l2_subdev_format_whence <v4l2-subdev-format-whence>`.
+
+    -  .. row 9
+
+       -  __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
+    :ref:`v4l2_subdev_frame_size_enum <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.