Unable to change display brightness with Function keys or Brightness and Lock application in Ubuntu 13.10

Question

I am having problem with Ubuntu 13.10 brightness control. My brightness shortcut keys (Fn + F5/F6) worked in 12.10 and 13.04 but they have stopped working in 13.10.

I am using Sony Vaio SVE15113ENB with VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09). Any help is appreciated.

I have tried following options, but none of them has worked so far:

1. Installing Additional Drivers from Software Centre
2. Finding /etc/X11/Xorg.con file for editing but it does not exist for me.
3. Visited Software & Updates > Additional Drivers tab, but it shows nothing saying 'No additional drivers available' and 'No proprietary drivers are in use'.

Thanks in advance for any help.

Answer 1

Try this.

• Execute $ sudo gedit /etc/default/grub

• Modify the line GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" to:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_backlight=vendor"

• Save the changes.

• Execute $ sudo update-grub

• Reboot.

Archlinux Wiki on brightness controls here.