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+.. This file is dual-licensed: you can use it either under the terms
+.. of the GPL 2.0 or the GFDL 1.1+ license, at your option. Note that this
+.. dual licensing only applies to this file, and not this project as a
+.. whole.
+..
+.. a) This file is free software; you can redistribute it and/or
+..    modify it under the terms of the GNU General Public License as
+..    published by the Free Software Foundation version 2 of
+..    the License.
+..
+..    This file is distributed in the hope that it will be useful,
+..    but WITHOUT ANY WARRANTY; without even the implied warranty of
+..    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+..    GNU General Public License for more details.
+..
+.. Or, alternatively,
+..
+.. b) 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/userspace-api/media/fdl-appendix.rst.
+..
+.. TODO: replace it to GPL-2.0 OR GFDL-1.1-or-later WITH no-invariant-sections
+
+.. _media_ioc_request_alloc:
+
+*****************************
+ioctl MEDIA_IOC_REQUEST_ALLOC
+*****************************
+
+Name
+====
+
+MEDIA_IOC_REQUEST_ALLOC - Allocate a request
+
+
+Synopsis
+========
+
+.. c:function:: int ioctl( int fd, MEDIA_IOC_REQUEST_ALLOC, int *argp )
+    :name: MEDIA_IOC_REQUEST_ALLOC
+
+
+Arguments
+=========
+
+``fd``
+    File descriptor returned by :ref:`open() <media-func-open>`.
+
+``argp``
+    Pointer to an integer.
+
+
+Description
+===========
+
+If the media device supports :ref:`requests <media-request-api>`, then
+this ioctl can be used to allocate a request. If it is not supported, then
+``errno`` is set to ``ENOTTY``. A request is accessed through a file descriptor
+that is returned in ``*argp``.
+
+If the request was successfully allocated, then the request file descriptor
+can be passed to the :ref:`VIDIOC_QBUF <VIDIOC_QBUF>`,
+:ref:`VIDIOC_G_EXT_CTRLS <VIDIOC_G_EXT_CTRLS>`,
+:ref:`VIDIOC_S_EXT_CTRLS <VIDIOC_G_EXT_CTRLS>` and
+:ref:`VIDIOC_TRY_EXT_CTRLS <VIDIOC_G_EXT_CTRLS>` ioctls.
+
+In addition, the request can be queued by calling
+:ref:`MEDIA_REQUEST_IOC_QUEUE` and re-initialized by calling
+:ref:`MEDIA_REQUEST_IOC_REINIT`.
+
+Finally, the file descriptor can be :ref:`polled <request-func-poll>` to wait
+for the request to complete.
+
+The request will remain allocated until all the file descriptors associated
+with it are closed by :ref:`close() <request-func-close>` and the driver no
+longer uses the request internally. See also
+:ref:`here <media-request-life-time>` for more information.
+
+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.
+
+ENOTTY
+    The driver has no support for requests.