Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 47 insertions, 0 deletions

diff --git a/Documentation/media/uapi/rc/lirc-get-rec-resolution.rst b/Documentation/media/uapi/rc/lirc-get-rec-resolution.rst
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+.. -*- coding: utf-8; mode: rst -*-
+
+.. _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.