I'm having trouble getting brightness to work on a late 2010 MBP, when I hit F1 and F2 the notification pops up showing the brightness bar changing but the screen stays at 100% even going into settings and changing the brightness slider does nothing. This only started happening after I used the update manager to install all new updates (I installed mint 14 yesterday so I cant narrow down which update it was.
I tried xbrightness, didn't work
pommed, didn't work
I found a forum saying to add acpi_brightness=vendor right before "quiet splash" but when i loaded the kernel at boot I couldn't find quiet splash, I added it anyways and it didn't help
also many forums reference /etc/default/grub but I don't have a file named grub in that directory.
Is there something wrong with my mint installation? When I boot from a USB drive that doesn't have any updates installed everything works fine.