Brightness Control – Unable to Change Brightness on Lenovo Laptop

brightnessintel graphicskubuntulaptoplenovo

Brightness adjustment keys <Fn + /> have no effect (although they are recognized by the environment), and I can't change the brightness using GUI tools as well. This seems like a problem in Linux itself, not the desktop environment.

I can change the brightness in Windows OS, so it's not some kind of hardware fault.

Details:
          Lenovo B570 (Model Name: 20093)
          Integrated Intel HD graphics card
          Kubuntu 11.04 (Linux 2.6.38-10-generic, KDE 4.7.0), everything up to date
          No proprietary graphics drivers (only Wi-Fi one)

What I've tried:

  • Edit /etc/default/grubGRUB_CMDLINE_LINUX_DEFAULT: acpi_osi=Linux, acpi_backlight=vendor, nomodeset. And yes, I did update-grub
  • Edit /etc/X11/xorg.conf (no such file, even after sudo dpkg-reconfigure xserver-xorg)
  • Edit /proc/acpi/video/VGA/LCD/brightness (no such file)
  • sudo setpci -s 00:02.0 F4.B=XX (no effect)
  • xbacklight -set XX ("No outputs have backlight property")

How can I fix this issue?

Best Answer

Try this. It worked for my Ubuntu 14, Lenovo B570, Intel Graphics.

Open a terminal and create the following configuration file, if it does not exist:

sudo touch /usr/share/X11/xorg.conf.d/20-intel.conf

Now we need to edit this file. You can use any editor be it a terminal one or graphical.

sudo gedit /usr/share/X11/xorg.conf.d/20-intel.conf

Add the following lines to this file:

Section "Device"
        Identifier  "card0"
        Driver      "intel"
        Option      "Backlight"  "intel_backlight"
        BusID       "PCI:0:2:0"

EndSection

Save it. Log out and log in back.