Toshiba L840 Brightness Control Function Keys

[chperry]

I just installed Linux Mint Cinnamon on a new Toshiba L840. So far everything I have tested is working with the exception of the function keys (f2 and f3) to control screen brightness. I can control brightness with the settings application, just not with the keys. I seem to remember a change to a grub file adding a reference to a energy management control file that fixed this on some dells. Is there a similar fix for my Toshiba that I can try? I am new to Mint.

I did search the forums but did not find what I was looking for.

Thanks

[chperry]

I tried the following with NO SUCCESS:

$sudo gedit /etc/default/grub
modify line to read:
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_backlight=vendor"
$sudo update-grub

Then shut down and restart. Still no brightness control via function keys.

The instructions above were posted to a few ubuntu blogs/forums for various notebooks (Dell, Asus). However, this did not work for my Toshiba.