Laptop doesn't detect unplugged AC power, special keys stop working

Bug #82681 reported by Matej Kenda
42
Affects Status Importance Assigned to Milestone
linux-source-2.6.20 (Ubuntu)
Fix Released
Medium
Ben Collins

Bug Description

I have noticed that after I use the computer for some time the system isn't able to detect that the power cord was unplugged.
Power Manager's icon doesn't change and doesn't switch into powersave mode.

At the same time, the special keys on the laptop stop working (mute, volume up, volume down).

I have power on password set in the laptop's BIOS and occasionally the situation goes so bad that the keyboard is not functioning at startup and I am unable to enter the password.

To resolve this situation, I have to shut down the computer, unplug the power cord and remove the battery.

This workaround helps until the next reboot. It seems that this problem is triggered at shutdown.

I have searched the (k)ubuntu pages and googled around and found out that other people have similar problems. They seem to be related to a kernel module psmouse.

http://www.ubuntuforums.org/showthread.php?t=326491

I tried a workaround to unload the kernel module psmouse on shutdown which seems to resolve the problem.

Hardware details of HP Compaq nw8440:

$ cat /var/lib/acpi-support/*-*
68YVD Ver. F.0F
Hewlett-Packard
HP Compaq nw8440 (RH415EA#ABB)
F.0F

Kernel version:

$ uname -a
Linux mk 2.6.20-6-generic #2 SMP Wed Jan 31 20:53:39 UTC 2007 i686 GNU/Linux

$ dpkg -l | grep linux-image
ii linux-image-2.6.20-6-generic 2.6.20-6.11 Linux kernel image for version 2.6.20 on x86
ii linux-image-generic 2.6.20.6 Generic Linux kernel image

I am running Kubuntu Feisty Fawn with packages as of 1st February 2007.

Revision history for this message
Matej Kenda (matejken) wrote :
Revision history for this message
Igor Lautar (igorl) wrote :

I confirm the similar behaviour on HP nc8430. Problems only start after rebooting, solved only by removing AC and battery. It seams to be a problem with most newer HP laptops.

It does not happen when removing psmouse module before reboot/shutdown.

It happens to me in both dapper and edgy.

Changed in linux-source-2.6.20:
assignee: nobody → ben-collins
importance: Undecided → Medium
status: Unconfirmed → Fix Committed
Revision history for this message
Matej Kenda (matejken) wrote :

I tested the kernel from Ubuntu git containing the fix:

http://zeus2.kernel.org/git/?p=linux/kernel/git/bcollins/ubuntu-2.6.git;a=commit;h=29f0b9969512eb7b312b0760d7bea7e652e8764e

Fix confirmed: problem doesn't appear any more.

Changed in linux-source-2.6.20:
status: Fix Committed → Fix Released
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