Backlight can't be set, although possible using "xbacklight"

[FriedChicken]

On Jaunty I'm not able to set the backlight on my Samsung NC10 netbook although this is posssible using the command line tool "xbacklight".

I don't know how KDE 4/Solid tries to set the backlight, but I think xbacklight sets the brightness over XRandR.

I think setting the backlight is an essential function on a netbook as it has a big impact on the battery usage and the aimed user groups of netbooks are surely not only people who know the xbacklight-trick.

[Adam (lolicjusz)]

KDE4 probably tries to detect acpi method of brightess control, kpowersave on KDE3.5 do the same I think.
On Samsung NC10 there is no acpi method for brightness control, but Gnome uses xrandr to communicate with hal to control display. Kpowersave says there is no brightness control, and it's the same with powerdevil on KDE4. Adding xrandr support to powerdevil would do the trick.

[Andreas Schildbach (schildbach)]

Probably related to bug 313231?

[Jonathan Thomas (echidnaman)]

There seems to be some work for a fallback xrandr-based brightness control for KDE's hardware management layer going on here: http://websvn.kde.org/branches/work/coolos_backlight/

Dunno if it'll make it into KDE any time soon though.

[FriedChicken (domlyons)]

As I noticed today it's working on Jaunty.

Maybe someone can change the status oon kde-bugs.

[Rich Johnson (nixternal)]

Assigning to Linux, and then marking it a duplicate of #438763 since the issues are similar, a fix has been found, and it has been confirmed.