I have an Acer 6935G. When I change the brightness with the function keys, it does register in both /sys/devices/platform/acer-wmi/backlight/acer-wmi/{actual_brightness,brightness}, but it doesn't have any effect on the screen's actual brightness until the screen is turned off and on again with FN+F6. I believe this might be a regression, since I think I can remember it used to work at some point. But I have tried lots of different kernel versions and I can't find one where it worked, so maybe I imagined this. If I echo 9 > brightness, the screen brightness does not change even if I toggle the screen's brightness.
please attach the acpidump output.
please attach the output of "tree /sys/class/backlight"
Created attachment 23316 [details] acpidump output
Created attachment 23317 [details] tree -lL 3 /sys/class/backlight
this looks like an acer-wmi issue to me. reassign to Carlos.
This seems to have stalled?
i don't know, but we need to ping Carlos Corbacho...
please build a vanilla 2.6.32 kernel with CONFIG_ACPI_VIDEO=y. please attach the output of "grep . /sys/class/backlight/*/*" in the new kernel.
there is also ACPI video support on this laptop. so let's see if we can control the backlight via ACPI video driver instead of acer-wmi first.
ping...
close this bug report as there is no response for more than 1 month.