[description] dim with something like: echo 1000 > /sys/class/backlight/gta01-bl/brightness [filename] 
a c t u a l _ b r i g h t n e s s
m a x _ b r i g h t n e s s
s u b s y s t e m
u e v e n t
b r i g h t n e s s
p o w e r