Bug 17863

Summary: BACKLIGHT property on Dell Inspiron 630m (with i915) is strange
Product: xorg Reporter: William Grant <wgrant>
Component: Server/GeneralAssignee: Xorg Project Team <xorg-team>
Status: RESOLVED INVALID QA Contact: Xorg Project Team <xorg-team>
Severity: normal    
Priority: medium CC: kenyon
Version: 7.4 (2008.09)   
Hardware: x86 (IA32)   
OS: Linux (All)   
Whiteboard:
i915 platform: i915 features:

Description William Grant 2008-10-01 18:34:41 UTC 
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.
Comment 1 Adam Jackson 2018-06-12 18:43:50 UTC 
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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