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diff --git a/Documentation/media/uapi/v4l/vidioc-enum-framesizes.rst b/Documentation/media/uapi/v4l/vidioc-enum-framesizes.rst deleted file mode 100644 index cd97546a7122..000000000000 --- a/Documentation/media/uapi/v4l/vidioc-enum-framesizes.rst +++ /dev/null @@ -1,213 +0,0 @@ -.. 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/media/uapi/fdl-appendix.rst. -.. -.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections - -.. _VIDIOC_ENUM_FRAMESIZES: - -**************************** -ioctl VIDIOC_ENUM_FRAMESIZES -**************************** - -Name -==== - -VIDIOC_ENUM_FRAMESIZES - Enumerate frame sizes - - -Synopsis -======== - -.. c:function:: int ioctl( int fd, VIDIOC_ENUM_FRAMESIZES, struct v4l2_frmsizeenum *argp ) - :name: VIDIOC_ENUM_FRAMESIZES - - -Arguments -========= - -``fd`` - File descriptor returned by :ref:`open() <func-open>`. - -``argp`` - Pointer to struct :c:type:`v4l2_frmsizeenum` - that contains an index and pixel format and receives a frame width - and height. - - -Description -=========== - -This ioctl allows applications to enumerate all frame sizes (i. e. width -and height in pixels) that the device supports for the given pixel -format. - -The supported pixel formats can be obtained by using the -:ref:`VIDIOC_ENUM_FMT` function. - -The return value and the content of the ``v4l2_frmsizeenum.type`` field -depend on the type of frame sizes the device supports. Here are the -semantics of the function for the different cases: - -- **Discrete:** The function returns success if the given index value - (zero-based) is valid. The application should increase the index by - one for each call until ``EINVAL`` is returned. The - ``v4l2_frmsizeenum.type`` field is set to - ``V4L2_FRMSIZE_TYPE_DISCRETE`` by the driver. Of the union only the - ``discrete`` member is valid. - -- **Step-wise:** The function returns success if the given index value - is zero and ``EINVAL`` for any other index value. The - ``v4l2_frmsizeenum.type`` field is set to - ``V4L2_FRMSIZE_TYPE_STEPWISE`` by the driver. Of the union only the - ``stepwise`` member is valid. - -- **Continuous:** This is a special case of the step-wise type above. - The function returns success if the given index value is zero and - ``EINVAL`` for any other index value. The ``v4l2_frmsizeenum.type`` - field is set to ``V4L2_FRMSIZE_TYPE_CONTINUOUS`` by the driver. Of - the union only the ``stepwise`` member is valid and the - ``step_width`` and ``step_height`` values are set to 1. - -When the application calls the function with index zero, it must check -the ``type`` field to determine the type of frame size enumeration the -device supports. Only for the ``V4L2_FRMSIZE_TYPE_DISCRETE`` type does -it make sense to increase the index value to receive more frame sizes. - -.. note:: - - The order in which the frame sizes are returned has no special - meaning. In particular does it not say anything about potential default - format sizes. - -Applications can assume that the enumeration data does not change -without any interaction from the application itself. This means that the -enumeration data is consistent if the application does not perform any -other ioctl calls while it runs the frame size enumeration. - - -Structs -======= - -In the structs below, *IN* denotes a value that has to be filled in by -the application, *OUT* denotes values that the driver fills in. The -application should zero out all members except for the *IN* fields. - - -.. c:type:: v4l2_frmsize_discrete - -.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.7cm}| - -.. flat-table:: struct v4l2_frmsize_discrete - :header-rows: 0 - :stub-columns: 0 - :widths: 1 1 2 - - * - __u32 - - ``width`` - - Width of the frame [pixel]. - * - __u32 - - ``height`` - - Height of the frame [pixel]. - - - -.. c:type:: v4l2_frmsize_stepwise - -.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.7cm}| - -.. flat-table:: struct v4l2_frmsize_stepwise - :header-rows: 0 - :stub-columns: 0 - :widths: 1 1 2 - - * - __u32 - - ``min_width`` - - Minimum frame width [pixel]. - * - __u32 - - ``max_width`` - - Maximum frame width [pixel]. - * - __u32 - - ``step_width`` - - Frame width step size [pixel]. - * - __u32 - - ``min_height`` - - Minimum frame height [pixel]. - * - __u32 - - ``max_height`` - - Maximum frame height [pixel]. - * - __u32 - - ``step_height`` - - Frame height step size [pixel]. - - - -.. c:type:: v4l2_frmsizeenum - -.. tabularcolumns:: |p{1.4cm}|p{5.9cm}|p{2.3cm}|p{8.0cm}| - -.. flat-table:: struct v4l2_frmsizeenum - :header-rows: 0 - :stub-columns: 0 - - * - __u32 - - ``index`` - - IN: Index of the given frame size in the enumeration. - * - __u32 - - ``pixel_format`` - - IN: Pixel format for which the frame sizes are enumerated. - * - __u32 - - ``type`` - - OUT: Frame size type the device supports. - * - union { - - (anonymous) - - OUT: Frame size with the given index. - * - struct :c:type:`v4l2_frmsize_discrete` - - ``discrete`` - - - * - struct :c:type:`v4l2_frmsize_stepwise` - - ``stepwise`` - - - * - } - - - - - * - __u32 - - ``reserved[2]`` - - Reserved space for future use. Must be zeroed by drivers and - applications. - - - -Enums -===== - - -.. c:type:: v4l2_frmsizetypes - -.. tabularcolumns:: |p{6.6cm}|p{2.2cm}|p{8.7cm}| - -.. flat-table:: enum v4l2_frmsizetypes - :header-rows: 0 - :stub-columns: 0 - :widths: 3 1 4 - - * - ``V4L2_FRMSIZE_TYPE_DISCRETE`` - - 1 - - Discrete frame size. - * - ``V4L2_FRMSIZE_TYPE_CONTINUOUS`` - - 2 - - Continuous frame size. - * - ``V4L2_FRMSIZE_TYPE_STEPWISE`` - - 3 - - Step-wise defined frame size. - - -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. |