Wednesday, 12 November 2014

Double brightness events


For years, Ubuntu has had this bug where a lot of laptops react to
brightness adjustment in steps of 2 (or even 3). I believe this is not
by design (correct me if wrong).

It seems that the brightness keypress is handled in multiple places.
Possibly the OS does the adjustment, but does not consume the event and
then BIOS does another adjustment.

Some machines can be fixed with this trick:
# echo N > /sys/module/video/parameters/brightness_switch_enabled

Are there plans to fix this bug? It's quite obvious one and immediately
strikes you when you install and start using Ubuntu on a laptop.

Some affected laptops: Dell E4300, Asus F200CA, HP 6910p, Fujitsu E751...

Joonas Saarinen

ubuntu-devel mailing list
Modify settings or unsubscribe at: