Brightness key not working.

[Alice Wang]

Hi guys,

I got some problem with brightness key.

My laptop is CLEVO w255cz, I build and install Chromium on it.

After boot, I try volume key(F9/F10) is working, but brightness function is not working when I press F6/F7.

I can see the brightness bubble, but LED brightness does not change.

Use Fn+brightness(F8/F9), brightness no change, and no brightness bubble.

I google, found some information:

In Ubuntu terminal, input: sudo gedit /etc/default/grub

find 

     GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

and change to

     GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_os_name=Linux"

close it, and update grub

So, I edit build_kernel_image.sh, and add "acpi_os_name=Linux" on command area.

And rebuild, reinstall, try again F6/F7, still got same problem.

Fn+brightness key looks okay, LED brightness has change, but still no brightness bubble :' (

Any ideas? Thanks!

[Brian Gaskell]

Hey, 

  I know that this isn't a fix for the issue at hand, however, i found that if i adjust my brightness in the CMOS using the FN+F5, it increased it also when its booted.