linuxdebug/Documentation/userspace-api/media/rc/lirc-set-rec-carrier-range.rst

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.. SPDX-License-Identifier: GPL-2.0 OR GFDL-1.1-no-invariants-or-later
.. c:namespace:: RC
.. _lirc_set_rec_carrier_range:
********************************
ioctl LIRC_SET_REC_CARRIER_RANGE
********************************
Name
====
LIRC_SET_REC_CARRIER_RANGE - Set lower bound of the carrier used to modulate
IR receive.
Synopsis
========
.. c:macro:: LIRC_SET_REC_CARRIER_RANGE
``int ioctl(int fd, LIRC_SET_REC_CARRIER_RANGE, __u32 *frequency)``
Arguments
=========
``fd``
File descriptor returned by open().
``frequency``
Frequency of the carrier that modulates PWM data, in Hz.
Description
===========
This ioctl sets the upper range of carrier frequency that will be recognized
by the IR receiver.
.. note::
To set a range use :ref:`LIRC_SET_REC_CARRIER_RANGE
<LIRC_SET_REC_CARRIER_RANGE>` with the lower bound first and later call
:ref:`LIRC_SET_REC_CARRIER <LIRC_SET_REC_CARRIER>` with the upper bound.
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.