media: rc: harmonize infrared durations to microseconds

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" <[email protected]>
Cc: Hans Verkuil <[email protected]>
Cc: Maxim Levitsky <[email protected]>
Cc: Patrick Lerda <[email protected]>
Cc: Kevin Hilman <[email protected]>
Cc: Neil Armstrong <[email protected]>
Cc: Jerome Brunet <[email protected]>
Cc: Martin Blumenstingl <[email protected]>
Cc: Sean Wang <[email protected]>
Cc: Matthias Brugger <[email protected]>
Cc: Patrice Chotard <[email protected]>
Cc: Maxime Ripard <[email protected]>
Cc: Chen-Yu Tsai <[email protected]>
Cc: "David Härdeman" <[email protected]>
Cc: Benjamin Valentin <[email protected]>
Cc: Antti Palosaari <[email protected]>
Signed-off-by: Sean Young <[email protected]>
Signed-off-by: Mauro Carvalho Chehab <[email protected]>

0 files changed, 0 insertions, 0 deletions