Re: Bug Report - [Acer Aspire V5-122P] Unable to adjust screen brightness

Aaron Lu
2014-05-23T01:35:21Z

On 05/21/2014 09:02 PM, Lewis Toohey wrote:
> Hi Aaron
>
> I followed your instructions and can report some limited success. I
> have two interfaces listed in /sys/class/backlight namely:
> acpi_video0 radeon_bl0
>
> max_brightness for acpi_video0 is 11. Echo-ing new values to
> brightness appears to have no effect.
>
> max_brightness for radeon_bl0 is 255. Echo-ing new values to
> brightness does adjust the screen brightness as you would expect.
>
> Results are the same on both battery and powered.
>
> I hope that is useful.

I think Hans' patchset should solve your problem, can you please give it
a try? You will need to pass the video.use_native_backlight=1 to kernel
cmdline when testing, thanks.

[PATCH resend 0/4] Make video.use_native_backlight=1 work properly with nouveau
http://www.spinics.net/lists/dri-devel/msg59941.html

-Aaron