Bug#477631: gnome-power-manager: g-p-m keeps resetting brightness

[Jan Echternach]

I have the same problem on a Dell Latitude D630.  Brightness seems to be
set through hardware (stopping acpid has no effect, and stopping hal just
prevents the brightness bar from appearing on the screen when I press the
brightness keys).

Brightness reset is triggered by gnome-screensaver.  Messages printed
by gnome-screensaver --no-daemon --debug when the brightness reset happens:

[power_timer] gs-watcher-x11.c:1080 (00:37:00):  in power timer
[power_timer] gs-watcher-x11.c:1098 (00:37:00):  Setting power notice elapsed: 30003
[watcher_power_notice_cb] gs-monitor.c:139 (00:37:00):   Power notice signal detected: 1
[_gs_watcher_set_session_power_notice] gs-watcher-x11.c:478 (00:37:00):  Changing power notice state: 1

I'm currently using "killall gnome-screensaver" as a workaround, but the
bug seems to be that g-p-m doesn't pick up any brightness changes made via
the keyboard unless I manually click on the brightness applet icon.  If I
do that, the gconf value of /apps/gnome-power-manager/backlight/brightness_ac
is updated, and the brightness is not reset later.

This kind of problem has already been reported multiple times to upstream,
see http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=467264#38.

BTW, I'd really like to have a checkbox labeled "Don't EVER automatically
change display brightness" in the g-p-m prefs dialog until all that
g-p-m brightness mess has been cleaned up.  It would save me from choosing
between dysfunctional brightness keys and a dysfunctional gnome-screensaver.