Change brightness on Asus laptop

I believe it's a big question among asus users, cause i've found tons of questions about "why do my backlight don't change with fn keys??".

Well... after to much researching and testing (I'm a linux noob btw :P), I found that the Fn keys change the value of the file /sys/class/backlight/asus_laptop/brightness. But, to change correctly the brightness, the file /sys/class/backlight/intel_backlight/brightness must be changed.

I even created a script to change it through bash, works alright and stuff... i just type ./brightness 50, where 50 means the % of the maximum brightness... but i still miss my Fn keys, for God's sake!!

Then I tried to simply change the symlinks that redirects the folders (asus_laptop and intel_backlight are symlinks to very opposed directions), but not even sudo was capable to change these symlinks...

In resume, I'm asking help to re-enable my Fn keys to work with the backlight brightness.

Thanks!

Ok, I think I found it. Edit your /etc/default/grub file:

sudo nano /etc/default/grub

Change the following line:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

to say this instead:

GRUB_CMDLINE_LINUX_DEFAULT="acpi_osi=! acpi_backlight=native idle=nomwait quiet splash"

Press CTRL + o and then press ENTER to save the file. Press CTRL + x to exit nano.

Finally, update grub and then reboot:

sudo update-grub

source