Comment # 21 on bug 1180749 from Antony J.R

(In reply to Takashi Iwai from comment #20)
> Thanks.  Then I misunderstood situation as if the backlight control didn't
> take any effect.
> 

I mean the backlight is constantly at maximum brightness and I can't decrease
or control it. The only thing works is the brightness slider in OpenSUSE and
the brightness value is only reflected in
/sys/class/backlight/amdgpu_bl0/brightness file but the backlight does not
change at all. I think I misled you saying "Here the brightness changed when
changed the brightness but actual_brightness is stuck at 311 constantly.", Here
I said /sys/class/backlight/amdgpu_bl0/brightness changes when I change the
brightness slider in the OS (or Fn Keys) but the backlight still remains at
maximum brightness. 

> Now I refreshed the OBS KMP repo to contain the possible fix.  It's being
> rebuilt, and please give it a try later.  The rpm changelog should contain
> the entry like:
> - Add a proper fix (attempt):
>   0001-drm-amd-display-Fix-the-brightness-read-via-aux.patch
> 
> At first, uninstall the previous KMP, just do "zypper rm
> amdgpu-dbg-kmp-default"
> Then re-install the new rpm, run mkinitrd and retest.  This doesn't contain
> the debug prints, so report back whether it works or not.

I will report back ASAP.