[Intel-gfx] i915 backlight

Aaron Lu aaron.lu at intel.com
Fri Aug 2 08:36:35 CEST 2013


On 08/02/2013 02:25 PM, Josep Lladonosa wrote:
> Hello,
> 
> I am using a Lenovo Edge E530 and, with kernel 3.11.0-rc3, I had to
> change to this parameter to the kernel boot:
> 
> 
> GRUB_CMDLINE_LINUX="acpi_osi=\"!Windows 2012\""

What if you remove the above from kernel command line, and add
video.brightness_switch_enabled=0 to kernel command line, then set the
following in xorg.conf:
$ cat /etc/X11/xorg.conf
Section "Device"
        Option     "Backlight"	"intel_backlight"
	Identifier  "Card0"
	Driver      "intel"
	BusID       "PCI:0:2:0"
EndSection

Does everything work?

If not, please test if manually change brightness level through sysfs
works:
# cd /sys/calss/backlight/intel_backlight
# echo xxx > brightness

And also test if hotkey event is sent out or not by running acpi_listen
and then press the hotkey.

Thanks,
Aaron

> 
> 
> instead of previous
> 
> GRUB_CMDLINE_LINUX="acpi_osi=Linux acpi_backlight=vendor"
> 
> to be able to change brightness. In some kernel versions before, it
> worked, but with 15 levels, but in graphical system brightness bar was
> not moving.
> 
> 
> Now I have, though, 8 possible values for brightness and brightness
> bar shows its correct position.
> 
> Josep
> 
> On 2 August 2013 08:00, Aaron Lu <aaron.lu at intel.com> wrote:
>> On 08/01/2013 04:07 PM, Borislav Petkov wrote:
>>> On Wed, Jul 31, 2013 at 11:16:52PM +0200, Rafael J. Wysocki wrote:
>>>> Does reverting efaa14c help?
>>>
>>> Nope.
>>>
>>> But see my other reply to Aaron.
>>
>> Assume you have specified to use intel_backlight in xorg.conf, does
>> booting with video.brightness_switch_enabled=0 help?
>>
>> Thanks,
>> Aaron
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to majordomo at vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at  http://www.tux.org/lkml/
> 
> 
> 




More information about the Intel-gfx mailing list