linux/drivers/media/usb/em28xx
Hans Verkuil 3aab15af9a media: add tuner standby op, use where needed
The v4l2_subdev core s_power op was used for two different things: power on/off
sensors or video decoders/encoders and to put a tuner in standby (and only the
tuner!). There is no 'tuner wakeup' op, that's done automatically when the tuner
is accessed.

The danger with calling (s_power, 0) to put a tuner into standby is that it is
usually broadcast for all subdevs. So a video receiver subdev that supports
s_power will also be powered off, and since there is no corresponding (s_power, 1)
they will never be powered on again.

In addition, this is specifically meant for tuners only since they draw the most
current.

This patch adds a new tuner op called 'standby' and replaces all calls to
(core, s_power, 0) by (tuner, standby). This prevents confusion between the two
uses of s_power. Note that there is no overlap: bridge drivers either just want
to put the tuner into standby, or they deal with powering on/off sensors. Never
both.

This also makes it easier to replace s_power for the remaining bridge drivers
with some PM code later.

Whether we want something cleaner for tuners in the future is a separate topic.
There is a lot of legacy code surrounding tuners, and I am very hesitant about
making changes there.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2018-03-21 12:05:39 -04:00
..
em28xx-audio.c media: em28xx-audio: fix coding style issues 2018-03-06 05:54:53 -05:00
em28xx-camera.c media: em28xx-camera: fix coding style issues 2018-03-06 05:54:53 -05:00
em28xx-cards.c media: em28xx-cards: fix em28xx_duplicate_dev() 2018-03-08 06:06:51 -05:00
em28xx-core.c media: em28xx: Change hex to lower case 2018-03-07 03:59:18 -05:00
em28xx-dvb.c media: em28xx: Enable inversion for Solo/Dual HD DVB models 2018-03-06 07:47:30 -05:00
em28xx-i2c.c media: em28xx-i2c: fix most coding style issues 2018-03-06 05:54:55 -05:00
em28xx-input.c media: em28xx-input: fix most coding style issues 2018-03-06 05:54:56 -05:00
em28xx-reg.h media: em28xx-reg.h: Fix coding style issues 2018-03-06 05:54:52 -05:00
em28xx-v4l.h media: em28xx: Add SPDX license tags where needed 2018-03-06 05:54:52 -05:00
em28xx-vbi.c media: em28xx: Add SPDX license tags where needed 2018-03-06 05:54:52 -05:00
em28xx-video.c media: add tuner standby op, use where needed 2018-03-21 12:05:39 -04:00
em28xx.h media: em28xx.h: Fix most coding style issues 2018-03-06 05:54:52 -05:00
Kconfig media: fix usage of whitespaces and on indentation 2018-01-04 13:12:01 -05:00
Makefile media: don't include drivers/media/i2c at cflags 2017-12-28 14:14:09 -05:00