Brightness Control

[ahimmerman]

Hello,

I'm running Linux Mint 13 stock with Cinnamon on a Lenovo ThinkPad W520 4276-39U laptop with an NVIDIA Quadro M1000 GF108GL (NVIDIA driver version 295.40). The Fn+Home and Fn+End (LED brightness increase and decrease, respectively), works when in consoles; however, in Cinnamon, they don't. When those keys are clicked, the brightness slider pops up and indicates changes, though brightness doesn't change. Also, the software brightness control, under Cinnamon Settings: Brightness and Lock, also has no effect.

Not sure if it's relevant, though, while trying to work through the issue, I switched the kernel from acpi_backlight=vendor (implicit default) to acpi_backlight=thinkpad_acpi. When operating under that driver, Fn+Home and Fn+End poped the brightness slider up, yet no change was indicated (and no change occurred). Also, under that driver, unhandled HKEY events were sent to syslog. Since then, I've restored the default configuration.

Any assistance would be appreciated.

Andrew

[okko7]

Try the following: 

Code: Select all

sudo nvidia-xconfig

(if there is no xorg.conf file yet)

Then

Code: Select all

sudo gedit /etc/X11/xorg.conf

Under "Section "Screen", before "EndSection" add:

Code: Select all

Option  "RegistryDwords" "EnableBrightnessControl=1"


So that section would look something like this (yours might not be exactly the same) -

Code: Select all

Section "Screen"
    Identifier     "Screen0"
    Device         "Device0"
    Monitor        "Monitor0"
    DefaultDepth    24
    SubSection     "Display"
        Depth       24
    EndSubSection
    Option      "RegistryDwords" "EnableBrightnessControl=1"
EndSection


Then reboot.

[sharat87]

Hi okko7,

I am facing this same problem but I don't have an nvidia card. I also don't have an `xorg.conf` file. Can you tell me how I can create it or otherwise get the brightness controls working?

Thank you.

[AmneetBedi]

Facing the same problem on Acer Aspire 5749 running Linux Mint 13 cinnamon. Tried modifying xorg.conf file as suggested above, but the issue still persists.

[lunatico]

Running Linux Mint 13 Cinnamon 32-bit on a Thinkpad W520. I was also having this problem and the suggestion from okko7 did fix it for me.

Thanks!

[Lebrontron]

I did this on my Lenovo z570 with a onboard intel graphics card. After restarting i got a prompt that X server has stopped working. Then on the command line i renamed the xorg.conf file i created to xorg.conf.failsafe and i could reboot the system into cinnamon. What's the right way please suggest.

[baliiii]

@okko7
Thanks mate.

[jvb]

@okko7 works for me too.

I had recently (19th August 2012) installed the latest graphics driver from NVIDIA (file:///home/jvb/downloads/installed/NVIDIA-Linux-x86_64-304.37.run) and lost the use of the brightness keys too, probably due to overwriting xconf.org in the NVIDIA driver installatiion.

x64 Linux Mint Debian Edition

[Xethron]

@okko7 Thanks! This works great! Bookmarked!