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diff --git a/Documentation/media/uapi/v4l/vidioc-g-priority.rst b/Documentation/media/uapi/v4l/vidioc-g-priority.rst deleted file mode 100644 index 244b4dbe9df3..000000000000 --- a/Documentation/media/uapi/v4l/vidioc-g-priority.rst +++ /dev/null @@ -1,100 +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_PRIORITY: - -****************************************** -ioctl VIDIOC_G_PRIORITY, VIDIOC_S_PRIORITY -****************************************** - -Name -==== - -VIDIOC_G_PRIORITY - VIDIOC_S_PRIORITY - Query or request the access priority associated with a file descriptor - - -Synopsis -======== - -.. c:function:: int ioctl( int fd, VIDIOC_G_PRIORITY, enum v4l2_priority *argp ) - :name: VIDIOC_G_PRIORITY - -.. c:function:: int ioctl( int fd, VIDIOC_S_PRIORITY, const enum v4l2_priority *argp ) - :name: VIDIOC_S_PRIORITY - - -Arguments -========= - -``fd`` - File descriptor returned by :ref:`open() <func-open>`. - -``argp`` - Pointer to an enum :c:type:`v4l2_priority` type. - - -Description -=========== - -To query the current access priority applications call the -:ref:`VIDIOC_G_PRIORITY <VIDIOC_G_PRIORITY>` ioctl with a pointer to an enum v4l2_priority -variable where the driver stores the current priority. - -To request an access priority applications store the desired priority in -an enum v4l2_priority variable and call :ref:`VIDIOC_S_PRIORITY <VIDIOC_G_PRIORITY>` ioctl -with a pointer to this variable. - - -.. c:type:: v4l2_priority - -.. tabularcolumns:: |p{6.6cm}|p{2.2cm}|p{8.7cm}| - -.. flat-table:: enum v4l2_priority - :header-rows: 0 - :stub-columns: 0 - :widths: 3 1 4 - - * - ``V4L2_PRIORITY_UNSET`` - - 0 - - - * - ``V4L2_PRIORITY_BACKGROUND`` - - 1 - - Lowest priority, usually applications running in background, for - example monitoring VBI transmissions. A proxy application running - in user space will be necessary if multiple applications want to - read from a device at this priority. - * - ``V4L2_PRIORITY_INTERACTIVE`` - - 2 - - - * - ``V4L2_PRIORITY_DEFAULT`` - - 2 - - Medium priority, usually applications started and interactively - controlled by the user. For example TV viewers, Teletext browsers, - or just "panel" applications to change the channel or video - controls. This is the default priority unless an application - requests another. - * - ``V4L2_PRIORITY_RECORD`` - - 3 - - Highest priority. Only one file descriptor can have this priority, - it blocks any other fd from changing device properties. Usually - applications which must not be interrupted, like video recording. - - -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 requested priority value is invalid. - -EBUSY - Another application already requested higher priority. |