From 528222d853f9283110f0118dd71d9f0ad686d586 Mon Sep 17 00:00:00 2001
From: Sean Young <sean@mess.org>
Date: Sun, 23 Aug 2020 19:23:05 +0200
Subject: media: rc: harmonize infrared durations to microseconds
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rc-core kapi uses nanoseconds for infrared durations for receiving, and
microseconds for sending. The uapi already uses microseconds for both,
so this patch does not change the uapi.

Infrared durations do not need nanosecond resolution. IR protocols do not
have durations shorter than about 100 microseconds. Some IR hardware offers
250 microseconds resolution, which is sufficient for most protocols.
Better hardware has 50 microsecond resolution and is enough for every
protocol I am aware off.

Unify on microseconds everywhere. This simplifies the code since less
conversion between microseconds and nanoseconds needs to be done.

This affects:
 - rx_resolution member of struct rc_dev
 - timeout member of struct rc_dev
 - duration member in struct ir_raw_event

Cc: "Bruno Prémont" <bonbons@linux-vserver.org>
Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Cc: Maxim Levitsky <maximlevitsky@gmail.com>
Cc: Patrick Lerda <patrick9876@free.fr>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: Jerome Brunet <jbrunet@baylibre.com>
Cc: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Cc: Sean Wang <sean.wang@mediatek.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Patrice Chotard <patrice.chotard@st.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: "David Härdeman" <david@hardeman.nu>
Cc: Benjamin Valentin <benpicco@googlemail.com>
Cc: Antti Palosaari <crope@iki.fi>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
---
 drivers/media/pci/cx23885/cx23888-ir.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'drivers/media/pci/cx23885')

diff --git a/drivers/media/pci/cx23885/cx23888-ir.c b/drivers/media/pci/cx23885/cx23888-ir.c
index ad7f8ccad526..ddfd2eb37484 100644
--- a/drivers/media/pci/cx23885/cx23888-ir.c
+++ b/drivers/media/pci/cx23885/cx23888-ir.c
@@ -663,7 +663,7 @@ static int cx23888_ir_rx_read(struct v4l2_subdev *sd, u8 *buf, size_t count,
 		}
 
 		v = (unsigned) pulse_width_count_to_ns(
-				  (u16) (p->hw_fifo_data & FIFO_RXTX), divider);
+				  (u16)(p->hw_fifo_data & FIFO_RXTX), divider) / 1000;
 		if (v > IR_MAX_DURATION)
 			v = IR_MAX_DURATION;
 
-- 
cgit