The next step that I'd like to take here is to look at what is in
"/sys/class/backlight", both without using the boot param
"acpi_backlight=vendor" and with it . To see what we might need to do in
order to get one backlight interface working, we need to know what
others exist. Without the boot param, I'd expect that we'd see
intel_backlight, possibly an nvidia brightness, and acpi_video0. With
the boot param, acpi_video0 should be replaced with a vendor specific
backlight.

Another quick thing that would be very helpful in guiding us to the root
of the problem is to try running the following as root "/bin/echo 0 >
/sys/class/backlight/intel_backlight/brightness" this will possibly
cause acpi_video0 to function properly, and therefore the brightness
keys should also function as expected. If this fixes the issue, it will
need to be reentered after a shutdown or a wake from suspend, but I
think there is an upstart script somewhere that could be tweaked to do
that.

Also, as a last thought for right now, what version of either nouveau or
the proprietary nvidia drivers are you using?

-- 
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.
https://bugs.launchpad.net/bugs/1218547

Title:
  Clevo W350ST brightness keys don't work on Kubuntu

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1218547/+subscriptions

-- 
ubuntu-bugs mailing list
ubuntu-bugs@lists.ubuntu.com
https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs

Reply via email to