Created attachment 70189 [details]
kernel config, dmesg output, lspci -xxxnnvv output

Hello there,

i have a acer travelmate 
5360-B812G50 laptop, and there is a problem with brightness control, 
please take a look to the result of my communication with acer_wmi module maintainer Joey Li :

> Hi Konstantin, 
> 
> I think the intel_gpu_tools v1.3 also toggle on a specific xorg version.
> That will be better check with X-window expert.
> 
> For the 'Couldn't map MMIO region' error is also strange.
> 
> Simply say, the i915 driver create intel_brightness when detected LVDS
> exist, i915 check register 0xe1180 of intel video chip for dtect LVDS
> status:
> 
> drivers/gpu/drm/i915/intel_lvds.c::intel_lvds_init
> ...
> if (HAS_PCH_SPLIT(dev)) {	/* if have split PCH, means pch_type != 
> PCH_NONE(0), issue machine have split CougarPoint PCH*/
> 	if ((I915_READ(PCH_LVDS) & LVDS_DETECTED) == 0)	/* read PCH_LVDS 0xe1180 > ??? */
> 		return false;
> 
> That's why we need the 'intel_reg_read 0xe1180' result, simply said we
> need the result of '(I915_READ(PCH_LVDS) & LVDS_DETECTED)'.
> 
> Per my understand, PCH_LVDS register should set by vBIOS, I am not sure
> there have other easy way to know the value of this register.
> 
> I think, if you want, it's time you can ping i915 driver expert. But, I
> must say this issue is still a OEM/ODM's problem.

I've place in attachment the dmesg with 
drm.debug=6, lspci results and config of my actual kernel ( vanilla 
3.6.3 without any additional patches ). I've try  the distribution 
2.6.32-5-686 (im using debian squeeze), vanilla 3.5.x branch, 3.0.x 
branch - without any success. 

Please help me to solve this issue if its possible, if you require any 
additional tests and outputs - let me know, i will provide you as much 
as possible informations.