linux/Documentation/userspace-api/media/rc/lirc-get-rec-resolution.rst
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   1.. SPDX-License-Identifier: GPL-2.0 OR GFDL-1.1-no-invariants-or-later
   2.. c:namespace:: RC
   3
   4.. _lirc_get_rec_resolution:
   5
   6*****************************
   7ioctl LIRC_GET_REC_RESOLUTION
   8*****************************
   9
  10Name
  11====
  12
  13LIRC_GET_REC_RESOLUTION - Obtain the value of receive resolution, in microseconds.
  14
  15Synopsis
  16========
  17
  18.. c:macro:: LIRC_GET_REC_RESOLUTION
  19
  20``int ioctl(int fd, LIRC_GET_REC_RESOLUTION, __u32 *microseconds)``
  21
  22Arguments
  23=========
  24
  25``fd``
  26    File descriptor returned by open().
  27
  28``microseconds``
  29    Resolution, in microseconds.
  30
  31Description
  32===========
  33
  34Some receivers have maximum resolution which is defined by internal
  35sample rate or data format limitations. E.g. it's common that
  36signals can only be reported in 50 microsecond steps.
  37
  38This ioctl returns the integer value with such resolution, with can be
  39used by userspace applications like lircd to automatically adjust the
  40tolerance value.
  41
  42Return Value
  43============
  44
  45On success 0 is returned, on error -1 and the ``errno`` variable is set
  46appropriately. The generic error codes are described at the
  47:ref:`Generic Error Codes <gen-errors>` chapter.
  48