14.04 Asus g56jr Fn + Brightness control

I have recently installed Ubuntu on my new Asus G56Jr laptop. I noticed that despite all the other Fn+fX keys are working, the screen brightness does not.

I have already tried editing the grub, as many here earlier advised, with no result. Also I tried using various drivers. ATM I am using the NVidia binary driver 331.38 and my grub file looks like this:

GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash pcie_aspm=force acpi_backlight=vendor"
GRUB_CMDLINE_LINUX=""

I know this has been already asked plenty of times, but I couldn' t find any working solution.

edit

Unlike many others I can actually set the brightess in Settings.

Solution 1:

I have an ASUS G56JK and had the same problem. It is now fixed for me.

In the terminal:

sudo gedit /etc/default/grub

Change

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

to

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi="

Save, then

sudo update-grub

Restart computer.

The function keys (fn+F5/F6) should now be active.

Solution 2:

The most generic option is to control brightness through the /sys class file as below echo 150 > /sys/class/backlight/intel_backlight/brightness. The highest value of this file is 946.

In addition, you can create a file /usr/share/X11/xorg.conf.d/20-intel-conf and put the below value:

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

Not sure if the below step is required, but i had used it prior to the above step, Edit /etc/default/grub and put the GRUB_CMDLINE_LINUX_DEFAULT as

 
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash pcie_aspm=force"
#GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_backlight=vendor"
GRUB_CMDLINE_LINUX=""

Then I did a sudo update-grub

You could also use the utility xbacklight and set-up keyboard shortcuts in unity/ Compiz to call it. Setting shortcut:
xbacklight -dec 5 to decrease by 5 units
xbacklight -inc 5 to increase.

While, the xbacklight will not solve "fn" keys, but it would give you a simple keyboard shortcut nonetheless.

Solution 3:

On my ASUS GL552vw with ubuntu 16.04:

Just working by adding acpi_backlight=native in /etc/default/grub:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash pcie_aspm=force acpi_osi= acpi_backlight=native"

EDIT 1

Don't forgett to update grub !

sudo update-grub