How to control power of a device from sysfs ?

[Umair Khan]

On Mon, Dec 5, 2016 at 12:56 PM, Ran Shalit <ranshalit at gmail.com> wrote:
> Hello,
>
> I am trying to turn off screen using sysfs entries,
> but I'm having some difficulties with it:
>
> 1.
> command:
> echo 0 > /sys/devices/platform/s5p-dsim.0/ea8061/backlight/panel/brightness
> result:
> screen is dimmed - BUT not turned off
>
> 2.
> command:
> cat
> /sys/devices/platform/s5p-dsim.0/ea8061/backlight/panel/actual_brightness
> 20
>
> This strengthen the fast that we didn't turned off brightness completely
>
> 3. In this point I though that maybe I can turn off the whole brightness
> device
>
> ls /sys/devices/platform/s5p-dsim.0/ea8061/backlight/panel/
> actual_brightness
> auto_brightness
> bl_power
> brightness
> device
> dimming
> max_brightness
> power
> subsystem
> type
> uevent
>
> I made some trials , but didn't made it turned off yet.
> Is there any idea if it's possible to turn it off completely ?

In my opinion, you'll need to have a look into the driver's code.
See if that exposes a mechanism to turn off the screen at all.

- Umair