I am using Toshiba Portege R835-P70 and function keys work as expected on Windows but they do not on Ubuntu 12.04. For e.g. Fn+F6 and Fn+F7 are supposed to change screen brightness but do not work.
What is the solution for this issue?
I tried adding
GRUB_CMDLINE_LINUX_DEFAULT=”quiet splash acpi_backlight=vendor“ to
/etc/default/grub, but it introduces an additional problem in that the laptop wakes up to a faintly visible dark screen from hibernation.
I know this is an old issue, but if it is so common, why isn't there a simple solution to it and why isn't it incorporated in latest versions of Ubuntu?