Comment 52 for bug 935778

Martin: With acpi_backlight=vendor and writing to toshiba/brightness after resume the backlight actually turns on, but leaves me with an empty screen. Xorg shows the following log entries:

[ 211.813] (WW) intel(0): flip queue failed: Invalid argument
[ 211.813] (WW) intel(0): Page flip failed: Invalid argument

I can change to a still working console and back to X, but X stays blank. By killing X I get back a working X server. The Fn-F6/7 keys still manipulate the intel_backlight interface and the screen brightness is changed thereby.

Seth: Without acpi_backlight=vendor nothing has changed. There isn't any difference between writing to toshiba/brightness manually or by script. The behaviour of the three interfaces is the same as before, see comment #33.