Bug 42182

Summary: Screen brightness is still set to MINIMUM and am unable to change it
Product: Drivers Reporter: Victor Marin (vms367)
Component: Video(DRI - non Intel)Assignee: drivers_video-dri
Status: RESOLVED OBSOLETE    
Severity: high CC: alan, alexdeucher
Priority: P1    
Hardware: All   
OS: Linux   
Kernel Version: 2.6.38 and up Subsystem:
Regression: Yes Bisected commit-id:

Description Victor Marin 2011-09-01 16:20:46 UTC
Hello,

Since the 2.6.38 Linux kernel version I am unable to modify the brightness of the screen and, what's worse, it goes to minimum bright automatically on start; The brightness panel applet does not work, neither to press Fn key + F9 nor Fn + F10.

I have a laptop HP 6735b with a ZM80 Turion X2 Ultra64 processor and an ATI HD 3200 graphics card.

So, I have re-installed Ubuntu 10.10, because Ubuntu 11.04 surprised me with a barely visible, not modifiable screen brightness.

This problem is in ALL Linux distributions with kernels 2.6.38, 2.6.39 and also with the new kernel 3.0., and above. 

Hence, I call your attention that I couldn't install any new or current Linux distro from Ubuntu 11.04 to Fedora 15, Linux Mint 11, Mandriva 2011 or even the just released Chakra Edn, as a few examples. And, likely many other users have the same problem.

Perhaps it has something to do with: 
http://www.phoronix.com/scan.php?page=news_item&px=OTYwMQ
Although, there they refer to battery duration problems.

I think, Linux shouldn't keep this screen brightness problem for much longer, as the laptop market is huge, even growing over the pc market and Windows, Mac or Google are out there as a huge competition.

Thanks in advance.

Regards,
Victor
Comment 1 Alex Deucher 2012-08-30 13:46:33 UTC
Is this still an issue with a newer kernel?  Make sure your kernel has the acpi backlight controls included.  My drm-next queue for 3.7 has support for native backlight control (assuming the OEM uses the on chip backlight controller) if you can't get the acpi backlight controls working.

http://cgit.freedesktop.org/~agd5f/linux/log/?h=drm-next-3.7-wip