Ubuntu – How to change the screen brightness on Zenbook UX305 with media-buttons

asuslaptopshortcut-keys

The keys fn+F5 and fn+F6 do not change the brightness on my Asus Zenbook UX305.
I can change the brightness from the command line with this command:

xrandr --output eDP1 --brightness 0.5

This example reduces the brightness to 50% of the rather bright default on the UX305.

But how can I use the default keys (see above) to change the brightness?

_{Warning: Do not use a brightness value greater than 1.0. Damage to your screen or eyes may result.}

Hardware: Asus Zenbook UX305, UX303UA, …
Ubuntu: 14.04, 16.04

Best Answer

I am having the same problem with the newer UX305CA. Apparently it is really common since the hardware is not recognized, so I just assigned a new shortcut. Following this answer:

sudo apt-get install xbacklight

Then assign new shortcut:

Settings > Keyboard > Shortcuts > Custom Shortcuts > +

Add those two:

Brightness up: xbacklight -inc 10
Brightness down: xbacklight -dec 10

Then click on each of the Disabled and select the new shortcut. In my case I used Alt+F5 and Alt+F6 (since I use Ctrl+F5 for web dev).

If you want, you can also mess with the boot options to fix it:

Hi,

I have the same problem. there is a workaround although.

add "acpi_osi=" at the and of the kernel boot parameters.

to permanently do this edit /etc/default/grub as root and add "acpi_osi=" at the end of GRUB_CMDLINE_LINUX_DEFAULT then run "update-grub" as root

after that brightness and all other hotkeys work but the ambient light sensor is no longer detected. But this is not a big problem since there is no standard ambient light regulation of screen brightness anyway

Related Solutions

Ubuntu – Brightness in ubuntu 12.04

Well this might be a workaround

Edit you rc.local file which will run on each startup,

sudo gedit /etc/rc.local

to write there something like,

echo 100 > /sys/class/backlight/intel_backlight/brightness

echo 100 > /sys/class/backlight/acpi_video0/brightness

depending on what defines your system brightness.

you can find out which brightness value is best for you by looking in the "actual_brightness" file. Then change the 100 for that number.

Laptop – Enable Brightness Buttons on Zenbook with acpi_osi in Grub

Add the option acpi_osi without value in the parameter GRUB_CMDLINE_LINUX_DEFAULT of your /etc/default/grub file, like in the body

# guillaume-desclaux https://ubuntuforums.org/showthread.php?t=2243162
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi="

Edit /usr/share/X11/xorg.conf.d/20-intel.conf and add the following there

# http://askubuntu.com/a/536618/25388
Section "Device"
        Identifier "card0"
        Driver "intel"
        Option "Backlight" "intel_backlight"
        BusID "PCI:0:2:0"
EndSection

Run sudo update-grub.

Output: brightness control works as expected now.

Best Answer

Related Solutions

Ubuntu – Brightness in ubuntu 12.04

Laptop – Enable Brightness Buttons on Zenbook with acpi_osi in Grub

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