The BACKLIGHT XRandR property on my Inspiron 630m operates rather strangely. I believe that the hardware normally controls brightness, but X seems to be able to do it too, albeit slowly: william@irranat:~$ xrandr --prop | grep -i light BACKLIGHT_CONTROL: combination BACKLIGHT: 15000 (0x00003a98) range: (0,15125) william@irranat:~$ xrandr --output LVDS --set BACKLIGHT 0 william@irranat:~$ # Over the next minute, the backlight will decrease slowly. william@irranat:~$ xrandr --output LVDS --set BACKLIGHT 15000 william@irranat:~$ # And now it will increase to maximum, similarly slowly. Both the slowness and the range are strange and confuse things like gnome-power-manager.
Mass closure: This bug has been untouched for more than six years, and is not obviously still valid. Please file a new report if you continue to experience issues with a current server.
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