Brightness controls not working on a Sony Vaio VPCEH38FN

Question

I have ubuntu 12.04 installed on windows 7. When I use the Fn alongside the key to reduce brightness, or even using the system settings, I am not being able to reduce the screen brightness. What is the problem?

Solution 1

Run:

sudo gedit /etc/default/grub

Update these lines:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
GRUB_CMDLINE_LINUX=""

... with the following arguments:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_backlight=vendor"
GRUB_CMDLINE_LINUX="acpi_osi=Linux"

Then run sudo update-grub and reboot.

Solution 2

I have a SONY VPCEG Vaio and to manipulate brightness in Ubuntu. Based on a article that I lost, I use this:

https://github.com/ricardodani/sony-vpc-brightness-linux/blob/master/bright.py

Solution 3

Here's how i fixed mine :

LCD Brightness Control

Once you have installed the proprietary Nvidia drivers as suggested above, you may notice that your brightness control keys do not work properly. This is fixable by editing one's xorg.conf file. Open a terminal window and type the following:

sudo nano /etc/X11/xorg.conf

This will open your X server configuration (after prompting for your password). You should see a section titled "Device" that looks as follows:

Section "Device"
        Identifier      "Default Device"
        Driver  "nvidia"
        Option  "NoLogo"        "True"
EndSection

Append a line so it appears like this:

Section "Device"
        Identifier      "Default Device"
        Driver  "nvidia"
        Option  "NoLogo"        "True"
        Option "RegistryDwords" "EnableBrightnessControl=1"
EndSection

You will need to restart your graphical server (or reboot) for this change to take effect.

Comments

[Admin]

@JorgeCastro it is sony vaio VPCEH38FN, but i dont know how it shud help

[Admin]

possible duplicate of Brightness doesn't change on Sony laptop

[Patrick Doyle]

hey..this is not working for me..Instead my Fn key has completely stoppd working, first it showed the brightness bar, but the brightness just didnt reduce..Now, it is not even showing the brightness level when I press the Fn key alongside key to reduce brigtness.

[deostroll]

Can you post the screenshots elsewhere and link here...so someone eventually come and modify this post to include it in your answer

[Admin]

hey christos, this is not working for me..i did exactly wt u said, but nothing is happening..

[Abhishek Kumar]

but u dont have the option to reduce or increase the brightness in this app..

[deostroll]

I've edited the answer with a pic...you can see the brightness slider...

[Abhishek Kumar]

is this in 12.04, cause i am not being able to see one...

[deostroll]

post the screenshot of your system settings on some image service like imgur...post that link here

[Abhishek Kumar]

OK. Hold on deostroll.

[deostroll]

May be you should update your post citing this difference...and regtag your post with 12.04, driver and support. Mention is a sony and publish its configuration out here.

[Eliah Kagan]

@christos If you post a comment with link(s) to screenshot(s), and you ping me in the comment (by including the string @EliahKagan), I'll put them in this answer for you.

[Peachy]

While this link may answer the question, it is better to include the essential parts of the answer here and provide the link for reference. Link-only answers can become invalid if the linked page changes.

[thorstorm]

It worked on my system with the 2 modifications on one line: GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi=Linux acpi_backlight=vendor"