back light regression since 3.6.11

Joseph Salisbury joseph.salisbury at
Fri Feb 15 16:07:16 UTC 2013

On 02/14/2013 03:33 PM, Chad McKean wrote:
> using xubuntu 12.10 64bit (using raring mainline kernels/stock raring 
> kernels)
> When i login using the 3.7.7 kernel and the 3.8 rc 4 through 7 kernels 
> by backlight changes to 100% also when running xbacklight -get my 
> brightness changes (90/91 percent or 100%)
> this is not a issue on the 3.6.11 raring mainline kernel, i don't 
> recall having a issue on some of the older stock raring 3.8 kernels 
> but i also updated my bios, so i cant confirm if they still work
> i know my backlight keys worked on 3.6.3 (old bios), but they are not 
> working on the 3.6.11 kernel (new bios) at least out of the box
> backlight keys do work on the 3.8 kernel, however 
> /sys/class/backlight/acpi_video0/brightness is not updated
> Laptop: Asus A54C-NB91
> Old Bios Version: 207
> New Bios Version: 210
> at first i was thinking it was the bios, but now i think it is the 
> combination of the kernel and the bios
> I may have some useful info here
> If a specific test senario is needed just send me a email and i will 
> try it asap, same goes for any info that is needed
Hi Chad,

Thanks for reporting this issue.  It would be best if you can open a bug 
report in Launchpad.  That will provide a way to track this issue and 
review your hardware, configuration, etc.

If you are not familiar with how to open a bug, the following wiki page 
should help:



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