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diff --git a/Documentation/media/uapi/v4l/vidioc-enum-frameintervals.rst b/Documentation/media/uapi/v4l/vidioc-enum-frameintervals.rst deleted file mode 100644 index 563a67cddeca..000000000000 --- a/Documentation/media/uapi/v4l/vidioc-enum-frameintervals.rst +++ /dev/null @@ -1,203 +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_FRAMEINTERVALS: - -******************************** -ioctl VIDIOC_ENUM_FRAMEINTERVALS -******************************** - -Name -==== - -VIDIOC_ENUM_FRAMEINTERVALS - Enumerate frame intervals - - -Synopsis -======== - -.. c:function:: int ioctl( int fd, VIDIOC_ENUM_FRAMEINTERVALS, struct v4l2_frmivalenum *argp ) - :name: VIDIOC_ENUM_FRAMEINTERVALS - - -Arguments -========= - -``fd`` - File descriptor returned by :ref:`open() <func-open>`. - -``argp`` - Pointer to struct :c:type:`v4l2_frmivalenum` - that contains a pixel format and size and receives a frame interval. - - -Description -=========== - -This ioctl allows applications to enumerate all frame intervals that the -device supports for the given pixel format and frame size. - -The supported pixel formats and frame sizes can be obtained by using the -:ref:`VIDIOC_ENUM_FMT` and -:ref:`VIDIOC_ENUM_FRAMESIZES` functions. - -The return value and the content of the ``v4l2_frmivalenum.type`` field -depend on the type of frame intervals 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_frmivalenum.type` field is set to - `V4L2_FRMIVAL_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_frmivalenum.type`` field is set to - ``V4L2_FRMIVAL_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_frmivalenum.type`` - field is set to ``V4L2_FRMIVAL_TYPE_CONTINUOUS`` by the driver. Of - the union only the ``stepwise`` member is valid and the ``step`` - value is set to 1. - -When the application calls the function with index zero, it must check -the ``type`` field to determine the type of frame interval enumeration -the device supports. Only for the ``V4L2_FRMIVAL_TYPE_DISCRETE`` type -does it make sense to increase the index value to receive more frame -intervals. - -.. note:: - - The order in which the frame intervals are returned has no - special meaning. In particular does it not say anything about potential - default frame intervals. - -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 interval enumeration. - -.. note:: - - **Frame intervals and frame rates:** The V4L2 API uses frame - intervals instead of frame rates. Given the frame interval the frame - rate can be computed as follows: - - :: - - frame_rate = 1 / frame_interval - - -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_frmival_stepwise - -.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.7cm}| - -.. flat-table:: struct v4l2_frmival_stepwise - :header-rows: 0 - :stub-columns: 0 - :widths: 1 1 2 - - * - struct :c:type:`v4l2_fract` - - ``min`` - - Minimum frame interval [s]. - * - struct :c:type:`v4l2_fract` - - ``max`` - - Maximum frame interval [s]. - * - struct :c:type:`v4l2_fract` - - ``step`` - - Frame interval step size [s]. - - - -.. c:type:: v4l2_frmivalenum - -.. tabularcolumns:: |p{1.8cm}|p{4.4cm}|p{2.4cm}|p{8.9cm}| - -.. flat-table:: struct v4l2_frmivalenum - :header-rows: 0 - :stub-columns: 0 - - * - __u32 - - ``index`` - - IN: Index of the given frame interval in the enumeration. - * - __u32 - - ``pixel_format`` - - IN: Pixel format for which the frame intervals are enumerated. - * - __u32 - - ``width`` - - IN: Frame width for which the frame intervals are enumerated. - * - __u32 - - ``height`` - - IN: Frame height for which the frame intervals are enumerated. - * - __u32 - - ``type`` - - OUT: Frame interval type the device supports. - * - union { - - (anonymous) - - OUT: Frame interval with the given index. - * - struct :c:type:`v4l2_fract` - - ``discrete`` - - Frame interval [s]. - * - struct :c:type:`v4l2_frmival_stepwise` - - ``stepwise`` - - - * - } - - - - - * - __u32 - - ``reserved[2]`` - - - - Reserved space for future use. Must be zeroed by drivers and - applications. - - - -Enums -===== - - -.. c:type:: v4l2_frmivaltypes - -.. tabularcolumns:: |p{6.6cm}|p{2.2cm}|p{8.7cm}| - -.. flat-table:: enum v4l2_frmivaltypes - :header-rows: 0 - :stub-columns: 0 - :widths: 3 1 4 - - * - ``V4L2_FRMIVAL_TYPE_DISCRETE`` - - 1 - - Discrete frame interval. - * - ``V4L2_FRMIVAL_TYPE_CONTINUOUS`` - - 2 - - Continuous frame interval. - * - ``V4L2_FRMIVAL_TYPE_STEPWISE`` - - 3 - - Step-wise defined frame interval. - - -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. |