Originally Posted by lonestar_italy
The biggest issue is I have to previously "rmmod sony-laptop" on my Vaio VPCCW1, for nvidiabl to work.
Seems like there is a sort of priority in how udev/upower see backlight devices, and they always use /sys/class/backlight/sony when it's present, instead of /sys/class/backlight/nvidia_backlight
Unfortunately sony-laptop does other things besides (trying to) handle backlight on a Sony, and keeping it blacklisted is a bad option. I haven't found any option to disable its backlight handling functions either
Is there any way to have both modules loaded at same time and KDE4 pick the correct backlight interface?
I had found a solution with hal by means of a configuration in /etc/hal/fdi/policy, but this is no longer possible with udev/upower.
The only solution I have found is to recompile kdebase-workspace after editing powerdevil/daemon/backends/upower/backlighthelper.cpp. Find the section:
interfaces << "nv_backlight" << "asus_laptop" << "toshiba"
<< "eeepc" << "thinkpad_screen" << "acpi_video0"
<< "mbp_backlight" << "acpi_video1"
<< "fujitsu-laptop" << "sony" << "samsung"
and move "nvidia_backlight" anywhere before "sony".
In this bug report https://bugs.kde.org/show_bug.cgi?id=257948
I have asked the maintainer to change the order in the original code, but he hasn't answered yet.