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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/media/uapi/fdl-appendix.rst.
+..
+.. TODO: replace it to GPL-2.0 OR GFDL-1.1-or-later WITH no-invariant-sections
+
+.. _media_request_ioc_reinit:
+
+******************************
+ioctl MEDIA_REQUEST_IOC_REINIT
+******************************
+
+Name
+====
+
+MEDIA_REQUEST_IOC_REINIT - Re-initialize a request
+
+
+Synopsis
+========
+
+.. c:function:: int ioctl( int request_fd, MEDIA_REQUEST_IOC_REINIT )
+ :name: MEDIA_REQUEST_IOC_REINIT
+
+
+Arguments
+=========
+
+``request_fd``
+ File descriptor returned by :ref:`MEDIA_IOC_REQUEST_ALLOC`.
+
+Description
+===========
+
+If the media device supports :ref:`requests <media-request-api>`, then
+this request ioctl can be used to re-initialize a previously allocated
+request.
+
+Re-initializing a request will clear any existing data from the request.
+This avoids having to :ref:`close() <request-func-close>` a completed
+request and allocate a new request. Instead the completed request can just
+be re-initialized and it is ready to be used again.
+
+A request can only be re-initialized if it either has not been queued
+yet, or if it was queued and completed. Otherwise it will set ``errno``
+to ``EBUSY``. No other error codes can be returned.
+
+Return Value
+============
+
+On success 0 is returned, on error -1 and the ``errno`` variable is set
+appropriately.
+
+EBUSY
+ The request is queued but not yet completed.