I have a Toshiba Satellite R830 laptop with Ubuntu 13.04.1 64 bit. The Fn + F6 and Fn + F7 buttons adjust brightness until I put my laptop on sleep.
On wakeup they don't work any longer.
On Ubuntu 12.04 and 12.10 I had the same issue but I solved it by modifying the
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" to
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi=Linux acpi_backlight=vendor"
This is no longer working on 13.04.
I noticed that before I put my laptop on sleep I can change the brightness by manually changing the value of the
/sys/class/backlight/toshiba/brightness file with the
echo 4 | sudo tee /sys/class/backlight/toshiba/brightness command. Values are 0 to 7.
I can also change the brightness manually by using the
echo 400 | sudo tee /sys/class/backlight/intel_backlight/brightness command. Values are much higher. I don't know the maximum or minimum, but setting it to 300 is very low and 4000 is very high.
After I put my laptop on sleep and wake it up again, the latter continue to work but not the former. It seems the shortcut keys and brightness control settings are bound to the
Is there a way to go solve this problem by pointing the shortcut keys to the
../intel_backlight/brightness value? or in some other way?
I would like to avoid using an old kernel if possible.