Four steps of brightness changing after pressing a brightness key only once

[Sympy]

Binary package hint: gnome-power-manager

As recommended by Andreas Wenning in Bug #207473, I'm opening a new bug report. Although there's several similar bugs already reported, I didn't find one I could really consider a duplicate.

My laptop is Dell Vostro 1400 with a GeForce 8400M GS and I'm using Hardy. When I press one of the brightness controls keys (Fn + Up or Fn + Down), four steps of brightness changing happen instead of just one. There seems to be a consensus in Bug #207473 that the problem lies on both hal and the desktop manager software responsible for power management. They both try to adjust the brightness and they both do two steps instead of one. A fix for kde-guidance, which supposedbly reduces the number of steps to two (in other words, fixes the problem on kde side but not on the hal side, which is still being worked on) is already available in hardy-proposed.

An example of what lshal -m reports when I press Fn + Up only once:

06:53:28.008: computer_logicaldev_input_1 condition ButtonPressed = brightness-up
06:53:28.010: computer_logicaldev_input condition ButtonPressed = brightness-up
06:53:28.011: platform_i8042_i8042_KBD_port_logicaldev_input condition ButtonPressed = brightness-up
06:53:28.200: platform_i8042_i8042_KBD_port_logicaldev_input condition ButtonPressed = brightness-up

[Sympy (sympathy4no1)]

Some other observations:

1) Executing /etc/acpi/video_brightnessdown.sh or /etc/acpi/video_brightnessup.sh changes the brightness just one step, but tweaking those scripts, or even deleting them, has no effect in the bug. It seems they are not called at all when the Fn keys are pressed, I don't know if this is expected behavior.

2) Blacklisting the video module fixes the four-step behavior, but causes other problems. A brightness change pop-up does not appear anymore, the brightness applet loses sync with the current brightness and trying to change brightness through the applet causes a two-second hanging for each step.

3) hal and gnome-power manager also seem to be conflicting in automatic brightness adjustment. A quick flicker when I unplug the ac cable indicates that the brightness was adjusted twice.

[enigma_0Z (enigma-0za)]

With regards to #3, this can be partially fixed by disabling a gconf key. In particular, /apps/gnome-power-manager/backlight/enable ... Disble this and AC unplug is fixed, but brightness key still has same affect.

By the way, same hardware: Vostro 1400, nVidia 8400 GS, Ubuntu Hardy, exactly same behavior.

[Griforg (griforg)]

Same behavior on Dell 6400 n 8.04

[Sympy (sympathy4no1)]

I recently noticed that the problem does not happen only with brightness keys. See Bug #239706.

[Pedro Villavicencio (pedro)]

Thanks for taking the time to report this bug and helping to make Ubuntu better. Could you please attach the resulting log file of: gnome-power-bugreport.sh &> gpm.log and a tarball of the /proc/acpi directory to the bug report? Thanks in advance.

[OliFre (freyermuth)]

The hal-update that arrived lately (yesterday?) fixes this, it seems.
However, unblacklisting the video-module breaks FN-F8 (CRT/LCD-Switcher) for me.
Brightness-control works fine again, even with video-module loaded.

Still, it would be nice if gnome-power-manager would have prevented it.

[Sympy (sympathy4no1)]

If such fix is true, this might be useless, but here it goes anyway:

[Sympy (sympathy4no1)]

By the way, are you talking about the recent update in the hal-info package?

If you are, this update has not fixed the problem for me.

[OliFre (freyermuth)]

Sympy: Yes, I am. That was the name I had lost ^^. For me, blacklisting the video-module fixed everything, and since the hal-info-update, I tried unblacklisting video again.
Reboot proved brightness control was still working for me.
However, the FN-F8 to switch from CRT to DFP/LCD is gone.
Hardware: Dell Vostro 1500, nVidia GeForce 8600M GT.

[Sympy (sympathy4no1)]

Ok, after confirming that my hal-info is up-to-date and rebooting to be even
more sure, I can safely say that the problem is not yet fixed for me.

[Román (roman-pena-perez)]

Hi, same problem here.
(BTW I'm sorry to have filed a duplicate bug; yesterday I couldn't find this thread).

IMHO it could be a kernel problem (conflicts between modules or else). If I run "showkey -s" within a VT, I get the following output, just by pressing "brightness up" (even if not releasing the key, which has no efects at all):

    0xe0 0x54 0xe0 0x54 0xe0 0xd4 0xe0 0x54 0xe0 0xd4 0xe0 0xd4 0xe0 0x54 0xe0 0xd4

and pressing "brightness down":

    0xe0 0x4c 0xe0 0x4c 0xe0 0xcc 0xe0 0x4c 0xe0 0xcc 0xe0 0xcc 0xe0 0x4c 0xe0 0xcc

Similar results with "showkey" without -s parameter (instead of two bytes groups it gives three bytes ones).

My system is a Dell Inspiron 9400, Ubuntu 8.04 LTS x86_64, up to date.

[Gabriel Rota (gabriel-rota)]

Same behavior on Dell Inspiron 6400 8.04.1
I use brightness applet.
Linux grota-laptop 2.6.24-21-generic #1 SMP Mon Aug 25 16:57:51 UTC 2008 x86_64 GNU/Linux

[Griforg (griforg)]

Still there in 8.10.

[EricDHH (ericdhh)]

Linux calliope 2.6.28-11-generic #42-Ubuntu SMP Fri Apr 17 01:57:59 UTC 2009 i686 GNU/Linux
ii gnome-power-ma 2.24.2-2ubuntu

Thinkpad T42. The brightness is switched down by gpm 3 or 4 steps, but only 2 steps up. This happens in AC mode and on battery, every few minutes the user has to lighten up the display. The osd shows the step when gpm control the backlight down. Saves lot of energy, but is extremly annoying. Thanks for tips to disable this completely.

Bye
Eric

[gracie (gracieatex)]

i am completely and utterly clueless . Dont know anything about computers and i've no idea what any of you are saying.

But the brightness on my laptop has gone weird and it seems really dull.I think i broke it. Has anyone got any suggestions ...in layman's terms - just for an indication -when i say laymans , i mean i can actually only use messengers and the internet. I have ubuntu... and dell inspiron 6400.

anything (other than abuse) would be helpful (=

thanks

[ethanay (ethan-y-us)]

running fresh install of 9.10 on Dell M1330

isn't there supposed to be just one step per actual button press? if so, i'm getting two...

11:07:03.785: platform_i8042_i8042_KBD_port_logicaldev_input condition ButtonPressed = brightness-up
11:07:03.799: computer_logicaldev_input condition ButtonPressed = brightness-up

11:07:05.477: computer_logicaldev_input condition ButtonPressed = brightness-down
11:07:05.477: platform_i8042_i8042_KBD_port_logicaldev_input condition ButtonPressed = brightness-down

This is an improvement over Hardy, no doubt, but still does not give me access to every brightness setting on the laptop!

[Román (roman-pena-perez)]

2009/11/2 ethanay <email address hidden>:
> running fresh install of 9.10 on Dell M1330
>
> isn't there supposed to be just one step per actual button press?  if
> so, i'm getting two...
>
> 11:07:03.785: platform_i8042_i8042_KBD_port_logicaldev_input condition ButtonPressed = brightness-up
> 11:07:03.799: computer_logicaldev_input condition ButtonPressed = brightness-up
>
> 11:07:05.477: computer_logicaldev_input condition ButtonPressed = brightness-down
> 11:07:05.477: platform_i8042_i8042_KBD_port_logicaldev_input condition ButtonPressed = brightness-down
>
> This is an improvement over Hardy, no doubt, but still does not give me
> access to every brightness setting on the laptop!
>
> --

 Yes, it improved to two key presses since 8.10 (Intrepid), but no
changes after that. I guess they solved just one duplication but
there's one more left.
 BTW, my machine has an odd number (7) of levels of brightness, so I
can get them all: start with the top one and then lower by one key
press at a time to get the odd levels, until you get to level 1, so
the next will be 0. Going up from there will give you the even ones,
until you get to 6, so the next will be 7, the top level, and you can
start all over again. I also used to have around the brightness applet
as a fall-back. Hope this helps.

  Román

[xteejx (xteejx)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. The issue that you reported is one that should be reproducible with the live environment of the Desktop CD of the development release - Lucid Lynx. It would help us greatly if you could test with it so we can work on getting it fixed in the next release of Ubuntu. You can find out more about the development release at http://www.ubuntu.com/testing/.
If this is still a problem in Lucid, please execute the following command, as it will automatically gather debugging information, in a terminal:
apport-collect 239413
This will help us to find and resolve the problem. Bear in mind that you may need to install the python-launchpadlib package from the universe repository. Additionally, when prompted to give apport-collect permissions for Launchpad you will need to give it at least the ability to "Change Non-Private" data as it will be adding information to your bug report. Thanks in advance!

[Román (roman-pena-perez)]

 Hi, I've recently updated to 9.10, and the problem no longer exists
for me. BTW I'm not going to try Lucid anytime soon, I'm sorry; maybe
others can report on that.

 Thank you for solving this issue,
 Román.

[xteejx (xteejx)]

This bug report is being closed due to your last comment regarding this being fixed with an update. For future reference you can manage the status of your own bugs by clicking on the current status in the yellow line and then choosing a new status in the revealed drop down box. You can learn more about bug statuses at https://wiki.ubuntu.com/Bugs/Status. Thank you again for taking the time to report this bug and helping to make Ubuntu better. Please submit any future bugs you may find.