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diff --git a/Documentation/media/uapi/v4l/vidioc-g-edid.rst b/Documentation/media/uapi/v4l/vidioc-g-edid.rst deleted file mode 100644 index e55b349a0c7e..000000000000 --- a/Documentation/media/uapi/v4l/vidioc-g-edid.rst +++ /dev/null @@ -1,154 +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_G_EDID: - -****************************************************************************** -ioctl VIDIOC_G_EDID, VIDIOC_S_EDID, VIDIOC_SUBDEV_G_EDID, VIDIOC_SUBDEV_S_EDID -****************************************************************************** - -Name -==== - -VIDIOC_G_EDID - VIDIOC_S_EDID - VIDIOC_SUBDEV_G_EDID - VIDIOC_SUBDEV_S_EDID - Get or set the EDID of a video receiver/transmitter - - -Synopsis -======== - -.. c:function:: int ioctl( int fd, VIDIOC_G_EDID, struct v4l2_edid *argp ) - :name: VIDIOC_G_EDID - -.. c:function:: int ioctl( int fd, VIDIOC_S_EDID, struct v4l2_edid *argp ) - :name: VIDIOC_S_EDID - - -.. c:function:: int ioctl( int fd, VIDIOC_SUBDEV_G_EDID, struct v4l2_edid *argp ) - :name: VIDIOC_SUBDEV_G_EDID - -.. c:function:: int ioctl( int fd, VIDIOC_SUBDEV_S_EDID, struct v4l2_edid *argp ) - :name: VIDIOC_SUBDEV_S_EDID - - -Arguments -========= - -``fd`` - File descriptor returned by :ref:`open() <func-open>`. - -``argp`` - Pointer to struct :c:type:`v4l2_edid`. - - -Description -=========== - -These ioctls can be used to get or set an EDID associated with an input -from a receiver or an output of a transmitter device. They can be used -with subdevice nodes (/dev/v4l-subdevX) or with video nodes -(/dev/videoX). - -When used with video nodes the ``pad`` field represents the input (for -video capture devices) or output (for video output devices) index as is -returned by :ref:`VIDIOC_ENUMINPUT` and -:ref:`VIDIOC_ENUMOUTPUT` respectively. When used -with subdevice nodes the ``pad`` field represents the input or output -pad of the subdevice. If there is no EDID support for the given ``pad`` -value, then the ``EINVAL`` error code will be returned. - -To get the EDID data the application has to fill in the ``pad``, -``start_block``, ``blocks`` and ``edid`` fields, zero the ``reserved`` -array and call :ref:`VIDIOC_G_EDID <VIDIOC_G_EDID>`. The current EDID from block -``start_block`` and of size ``blocks`` will be placed in the memory -``edid`` points to. The ``edid`` pointer must point to memory at least -``blocks`` * 128 bytes large (the size of one block is 128 bytes). - -If there are fewer blocks than specified, then the driver will set -``blocks`` to the actual number of blocks. If there are no EDID blocks -available at all, then the error code ``ENODATA`` is set. - -If blocks have to be retrieved from the sink, then this call will block -until they have been read. - -If ``start_block`` and ``blocks`` are both set to 0 when -:ref:`VIDIOC_G_EDID <VIDIOC_G_EDID>` is called, then the driver will set ``blocks`` to the -total number of available EDID blocks and it will return 0 without -copying any data. This is an easy way to discover how many EDID blocks -there are. - -.. note:: - - If there are no EDID blocks available at all, then - the driver will set ``blocks`` to 0 and it returns 0. - -To set the EDID blocks of a receiver the application has to fill in the -``pad``, ``blocks`` and ``edid`` fields, set ``start_block`` to 0 and -zero the ``reserved`` array. It is not possible to set part of an EDID, -it is always all or nothing. Setting the EDID data is only valid for -receivers as it makes no sense for a transmitter. - -The driver assumes that the full EDID is passed in. If there are more -EDID blocks than the hardware can handle then the EDID is not written, -but instead the error code ``E2BIG`` is set and ``blocks`` is set to the -maximum that the hardware supports. If ``start_block`` is any value -other than 0 then the error code ``EINVAL`` is set. - -To disable an EDID you set ``blocks`` to 0. Depending on the hardware -this will drive the hotplug pin low and/or block the source from reading -the EDID data in some way. In any case, the end result is the same: the -EDID is no longer available. - - -.. c:type:: v4l2_edid - -.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.7cm}| - -.. flat-table:: struct v4l2_edid - :header-rows: 0 - :stub-columns: 0 - :widths: 1 1 2 - - * - __u32 - - ``pad`` - - Pad for which to get/set the EDID blocks. When used with a video - device node the pad represents the input or output index as - returned by :ref:`VIDIOC_ENUMINPUT` and - :ref:`VIDIOC_ENUMOUTPUT` respectively. - * - __u32 - - ``start_block`` - - Read the EDID from starting with this block. Must be 0 when - setting the EDID. - * - __u32 - - ``blocks`` - - The number of blocks to get or set. Must be less or equal to 256 - (the maximum number of blocks as defined by the standard). When - you set the EDID and ``blocks`` is 0, then the EDID is disabled or - erased. - * - __u32 - - ``reserved``\ [5] - - Reserved for future extensions. Applications and drivers must set - the array to zero. - * - __u8 * - - ``edid`` - - Pointer to memory that contains the EDID. The minimum size is - ``blocks`` * 128. - - -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. - -``ENODATA`` - The EDID data is not available. - -``E2BIG`` - The EDID data you provided is more than the hardware can handle. |