Comment # 6 on bug 1180591 from Maurizio Galli

(In reply to Takashi Iwai from comment #1)
> Could you give the output of hwinfo and the output of dmesg?

See attachemnts

> Also, try to adjust the brightness by manually writing to sysfs files
> /sys/class/backlight/*/brightness.  The value ranges are found in
> /sys/class/backlight/*/max_brightness.  e.g. on my laptop, I can change it
> like
>   echo -n 200 > /sys/class/backlight/intel_backlight/brightness
> 
> There might be multiple entries in /sys/class/backlight and you can try each
> of them.

I tried and it did not help.

> 
> And, if it used to work with Leap kernel, could you try to install the
> latest Leap 15.2 kernel on the current system (with zypper install
> --oldpackage option), boot with it and test whether the brightness works?
> If Leap 15.2 kernel works, give again the output of hwinfo and dmesg from it.

I still had the Leap 15.2 kernel installed and booting into allows me to change
backlight. hwinfo and dmesg are attached. The issue only happens if I boot into
the current TW kernel 5.10