[media] doc-rst: document LIRC set carrier ioctls

Put each ioctl on its own page and improve documentation, adding
cross-references for LIRC_SET_REC_CARRIER_RANGE and LIRC_SET_REC_CARRIER,
with can be used together to set a carrier frequency range.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

1 files changed, 49 insertions, 0 deletions

diff --git a/Documentation/media/uapi/rc/lirc-set-rec-carrier-range.rst b/Documentation/media/uapi/rc/lirc-set-rec-carrier-range.rst
new file mode 100644
index 000000000000..7cce9c8ba361
--- /dev/null
+++ b/Documentation/media/uapi/rc/lirc-set-rec-carrier-range.rst
@@ -0,0 +1,49 @@
+.. -*- coding: utf-8; mode: rst -*-
+
+.. _lirc_set_rec_carrier_range:
+
+********************************
+ioctl LIRC_SET_REC_CARRIER_RANGE
+********************************
+
+Name
+====
+
+LIRC_SET_REC_CARRIER_RANGE - Set lower bond of the carrier used to modulate
+IR receive.
+
+Synopsis
+========
+
+.. cpp:function:: int ioctl( int fd, int request, __u32 *frequency )
+
+Arguments
+=========
+
+``fd``
+    File descriptor returned by open().
+
+``request``
+    LIRC_SET_REC_CARRIER_RANGE
+
+``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.