Ubuntu
gnome-power-manager package

  1. Bug #818826
  2. Comment #6

Comment 6 for bug 818826

Revision history for this message
kapouer (kapouer) wrote :

ACPI DSDT has actually two paths for changing backlight.
One is simple to understand and is using SMI Command Port B2, but only works when booting with BIOS.
The other is quite complicated (for me acpi noob) and is using a ressource called "smbus-ddcblc".
I don't know if the backlight acpi is failing because it doesn't follow the right code path (in which case acpi
think it's bios where it isn't) or because memory is not mapped as acpi thinks it should be, or... ?