Ubuntu
linux package

  1. Bug #1178205
  2. Comment #5

Comment 5 for bug 1178205

Revision history for this message
Jens (jens-launchpad-net) wrote : Re: Screen brightness not changable via applet or hotkeys in Ubuntu 12.04 on Toshiba R850 notebook

After further testing:

With "acpi_backlight=vendor", brightness is adjustable in about 20 steps until the first suspend, the minimum setting switches the display off completely. After resume, the "brightness" file in /sys says "7" (max value) but the screen backlight is off. This is irrespective of an external monitor connected to my notebook.

Without "acpi_backlight=vendor", the brightness is adjustable in 8 steps until the first suspend, the minimum setting sets the screen very dark, but still readable. After resume, "actual_brightness" is 0, "brightness" is 7, the hotkeys show a popup window with an adjustable brightness bar, but the actual brightness of the screen is fixed to the value it had before suspending, and is not changeable any more with the hotkeys.