gnome-power-manager brightness control is crazy

[thbone]

Binary package hint: gnome-power-manager

I have a P35 Laptop and everytime after each restart the monitor starts to jitter and I have no brightness control also the problem shows up after five-ten minutes.

I can see the brightness control box but it seems frozen. The brighntess of the monitor goes endless up and down with no user control and the monitor jitters

the brightness control with "fn" button doesn't work.

only solution I found was to kill the gnome-power-manager - then I have control over brightness back and
the "fn" button works again

version installed: gnome power manager 2.20.0-0ubuntu3

[Nikolaus Filus (nfilus)]

BIG FAT ACK! I have here also a Samsung P35

I'm also the reporter of bug #136346 - g-p-m is still absolutely broken. The procedure looks like follows:

reboot
gnome, log in
while true; do
    killall gnome-power-manager
    rm -rf ~/.gconf/apps/gnome-power-manager
done

more issues:
 - brightness control with Fn+Up or +Down only one level each time or g-p-m burns CPU with endless change events
   seen with

dbus-monitor --system
  signal sender=:1.3 -> dest=(null destination) path=/org/freedesktop/Hal/devices/platform_i8042_i8042_KBD_port_logicaldev_input;
  interface=org.freedesktop.Hal.Device; member=Condition
   string "ButtonPressed"
   string "brightness-down"
  ..... repeat .....

and lshal -m
  21:25:55.541: platform_i8042_i8042_KBD_port_logicaldev_input condition ButtonPressed = brightness-up
  21:25:55.748: platform_i8042_i8042_KBD_port_logicaldev_input condition ButtonPressed = brightness-up
  ..... repeat .....

 - dim display when idle when on battery causes brightness go down to 0% and back to 100%
   (or flashes display and burns CPU)

[thbone (rabo69)]

addition: I found out that the bug shows always up if I boot the laptop connected to the powerline.
                 If the laptop is booted in battery mode without connection to the powerline it seems
                 to work without the crazy behaviour.

[thbone (rabo69)]

additiion: I found out that the P35 has a BIOS option "BOOT / Brightness Control" and I swichted it to "User Control" from "Auto-Dim"
                and it seems that the problem happend now only just after login - but then it works.

                In Edgy and Feisty the gnome-power-manager works without a BIOS change.

[Peter Meiser (meiser79)]

Hi,

I also own a P35. The problem is not gnome-power-manager, but a broken DSDT.

When g-p-m changes the brightness through the backlight sysfs (/sys/class/backlight/asus/brightness), there's also an ACPI event generated as if the user pressed the the Fn keys.

The workaround is not to kill g-p-m, but to comment out the acpi_fakekey command in /etc/acpi/asus-brn-down.sh and /etc/acpi/asus-brn-up.sh

But I agree, a solution would be great to have the OSD and the g-p-m features.

Best regards,
Whoopie

[thbone (rabo69)]

Whoopie - thx for the Tip.

after my last synaptic update "auto-dim" off solution didn't work anymore - the brightness control problem is back

[Nikolaus Filus (nfilus)]

Whoopie's workaround works, but then no OSD is shown for brightness changes with the Fn keys.

As far as I understand his explanation the current setup produces a loop of acpi events. But it seems, there is
also a bug in processing this events in g-p-m. I think g-p-m tries to control the brightness at every moment
and checks the value in the wrong place (?).

BTW: my brightness control in BIOS was always set to "user control".

[philipp beitz (philippbeitz)]

https://bugs.launchpad.net/ubuntu/+source/gnome-power-manager/+bug/145131
https://bugs.launchpad.net/ubuntu/+source/hal/+bug/151675

[Peter Meiser (meiser79)]

Hi,

I found another workaround. I applied the patch from bug 137598 (http://launchpadlibrarian.net/9690288/gpm-backlight.c.diff) and disabled "auto-dimming on AC/battery while idle" in g-p-m preferences.

Now, you can have an OSD, but not auto-dimming.

Best regards,
Whoopie

[Hfr (hfre)]

Hello

thanks for having looked for a solution formerly - I dare say it could not be up again.

I've this problem never seen using Ubuntu 9.04 but now with Ubuntu 9.10 Beta.

My hardware:

Netbook „MSI Wind U100-1616XP Luxury Edition 0011221-SKU201" (gekauft 31.3.09)

I 've seen another related topic:
https://bugs.launchpad.net/ubuntu/+source/gnome-power-manager/+bug/415023

Is someone looking after this topic?

Best Regards from Munich (Germany)

[Hfr (hfre)]

Oops:
I dare say it could be up again.

[rinaldo (rinaldo-forte)]

i have found this workaround
remove this line:

KEY_BRIGHTNESSDOWN=224
KEY_BRIGHTNESSUP=225

from /usr/share/acpi-support/key-constants

it work in my netbook

[Pavel Nazarov (alsvartr)]

I've found this workaround for the Samsung n210 netbook:

1. Add this to GRUB_CMDLINE_LINUX_DEFAULT line in /etc/default/grub:
"quiet splash acpi_backlight=vendor intel_idle.max_cstate=0"
2. update-grub
3. update-initramfs -u