Hi,

I'm not sure if I have posted in the correct forum. Please move or point me where to ask.

I have a new Asus Zenbook UX32A with Debian Wheezy 7.1 amd64 and KDE 4.8.4 installed. There is a strange problem regarding screen dimming and power management. I have found no relevant articles/discussions on it.

How to reproduce:
1) Start Debian, wait for KDE to start (do not login);
2) Plug AC Adapter in and then plug it out and as a result no bad things happen;
3) Log in to a KDE session;
4) Plug AC Adapter in. As a result display turns off.
5) Plug AC Adapter out. Display turns on!
6) Open Energy Saving Settings, change state of "Dim display" checkbox for current mode, press "Apply" button. Display turns off!
7) Plug AC Adapter in. Display turns on!

Additionally when AC Adapter is plugged the following records are appearing in the dmesg:

Sat Sep 28 01:38:55 2013 asus_wmi: Unknown key 58 pressed
Sat Sep 28 01:39:04 2013 asus_wmi: Unknown key 57 pressed

I figured out that the following records are appearing in log when the screen is turning off:

Sep 28 01:38:45 windj-zen dbus 2600 : system Activating service name='org.kde.powerdevil.backlighthelper' (using servicehelper)
Sep 28 01:38:45 windj-zen dbus 2600: [system Successfully activated service 'org.kde.powerdevil.backlighthelper'

Kernel args (pcie*, acpi* were added in attempts to solve this problem, they have changed nothing):

ro root=/dev/sda5 pcie_aspm=force acpi_osi=Linux acpi_backlight=vendor

Buttons that are to control the brightness of the display (Fn+F5 and Fn+F6) don't work but the Fn+F7 button turns display on and off as it should do.

Obviously killing upowerd solves the problem but it's undesirable to disable energy saving on laptop.

Is it a known bug and I just have not found it?
Is there a workaround without disabling entire power management subsystem?

I think there was a bug regarding displays in this version of powerdevil / KDE workspace. Unfortunately the version shipped by Debian is very old (we're at 4.11 now), so that means it's hard to tell if this issue was fixed or not.

Thank you for the answer! I bypassed this problem by upgrading my Debian installation to current testing branch (Jessie). The upgrade also solved a number of other issues (soft keys, touchpad, sound etc.). My previous notebook (Asus EeePC 1015PX) also had issues with Debian stable (then it was Squeeze) and the solution was also to upgrade to testing.

The topic may be considered to be closed.