ASUS gaming laptops users, I need you

Hi everybody.
Since I’ve started to using linux on my ASUS-FX503VD-E4082 my Fn key combos have never worked except volume control.
Had anyone solved this issue?
I have applied different patches from the same related topics on bugzilla, but nothing helps.
I am ready to modify hid driver, but I don’t know where to start. Could anyone recommend any useful docs? Cuz i have’nt found any.