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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_request_ioc_queue:
+
+*****************************
+ioctl MEDIA_REQUEST_IOC_QUEUE
+*****************************
+
+Name
+====
+
+MEDIA_REQUEST_IOC_QUEUE - Queue a request
+
+
+Synopsis
+========
+
+.. c:function:: int ioctl( int request_fd, MEDIA_REQUEST_IOC_QUEUE )
+    :name: MEDIA_REQUEST_IOC_QUEUE
+
+
+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 queue a previously allocated request.
+
+If the request was successfully queued, then the file descriptor can be
+:ref:`polled <request-func-poll>` to wait for the request to complete.
+
+If the request was already queued before, then ``EBUSY`` is returned.
+Other errors can be returned if the contents of the request contained
+invalid or inconsistent data, see the next section for a list of
+common error codes. On error both the request and driver state are unchanged.
+
+Once a request is queued, then the driver is required to gracefully handle
+errors that occur when the request is applied to the hardware. The
+exception is the ``EIO`` error which signals a fatal error that requires
+the application to stop streaming to reset the hardware state.
+
+It is not allowed to mix queuing requests with queuing buffers directly
+(without a request). ``EBUSY`` will be returned if the first buffer was
+queued directly and you next try to queue a request, or vice versa.
+
+A request must contain at least one buffer, otherwise this ioctl will
+return an ``ENOENT`` error.
+
+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.
+
+EBUSY
+    The request was already queued or the application queued the first
+    buffer directly, but later attempted to use a request. It is not permitted
+    to mix the two APIs.
+ENOENT
+    The request did not contain any buffers. All requests are required
+    to have at least one buffer. This can also be returned if some required
+    configuration is missing in the request.
+ENOMEM
+    Out of memory when allocating internal data structures for this
+    request.
+EINVAL
+    The request has invalid data.
+EIO
+    The hardware is in a bad state. To recover, the application needs to
+    stop streaming to reset the hardware state and then try to restart
+    streaming.