media: docs: move uAPI book to userspace-api/media

Since 2017, there is an space reserved for userspace API,
created by changeset 1d596dee3862 ("docs: Create a user-space API guide").

As the media subsystem was one of the first subsystems to use
Sphinx, until this patch, we were keeping things on a separate
place.

Let's just use the new location, as having all uAPI altogether
will likely make things easier for developers.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

1 files changed, 54 insertions, 0 deletions

diff --git a/Documentation/userspace-api/media/rc/lirc-get-rec-resolution.rst b/Documentation/userspace-api/media/rc/lirc-get-rec-resolution.rst
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index 000000000000..f20b5bf41232
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+.. 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 GFDL-1.1-or-later WITH no-invariant-sections
+
+.. _lirc_get_rec_resolution:
+
+*****************************
+ioctl LIRC_GET_REC_RESOLUTION
+*****************************
+
+Name
+====
+
+LIRC_GET_REC_RESOLUTION - Obtain the value of receive resolution, in microseconds.
+
+Synopsis
+========
+
+.. c:function:: int ioctl( int fd, LIRC_GET_REC_RESOLUTION, __u32 *microseconds)
+    :name: LIRC_GET_REC_RESOLUTION
+
+Arguments
+=========
+
+``fd``
+    File descriptor returned by open().
+
+``microseconds``
+    Resolution, in microseconds.
+
+
+Description
+===========
+
+Some receivers have maximum resolution which is defined by internal
+sample rate or data format limitations. E.g. it's common that
+signals can only be reported in 50 microsecond steps.
+
+This ioctl returns the integer value with such resolution, with can be
+used by userspace applications like lircd to automatically adjust the
+tolerance value.
+
+
+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.