ThinkPad T61: num lock key generates an input event when turning on, but not off
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
linux (Ubuntu) |
Fix Released
|
Medium
|
Lee Jones |
Bug Description
As originally reported as part of bug 280646 (with some further analysis there), there seems to be no input event generated when the user presses the num lock key to turn it off. This is a problem because num lock state is tracked in software, and becomes out of sync with the hardware state.
Some places where this problem can be observed include:
1. GNOME: turn num lock on and then off. gconftool-2 --get /desktop/
2. X modifier state: Run xkbwatch, turn num lock on and then off. The num lock modifier remains lit (should turn off)
3. Kernel input layer: Using input-events from input-utils, watch events on the AT keyboard device (must be done on the console). Key press events are seen (for the Fn and num lock keys) the first time num lock is activated, but not the second time.
It's been suggested that this may be a hardware or BIOS issue, but seems to need further investigation.
ProblemType: Bug
Architecture: amd64
DistroRelease: Ubuntu 8.10
Package: linux-image-
ProcCmdLine: root=UUID=
ProcEnviron:
LC_COLLATE=C
PATH=/
LANG=en_US.UTF-8
SHELL=/bin/zsh
ProcVersionSign
SourcePackage: linux
Changed in linux: | |
assignee: | nobody → ubuntu-kernel-team |
importance: | Undecided → Medium |
status: | New → Triaged |
tags: | added: lucid |
Changed in linux (Ubuntu): | |
assignee: | nobody → Lee Jones (lag) |
Changed in linux (Ubuntu): | |
status: | New → In Progress |
Bryce Harrington says in bug 280646:
"On the Thinkpad T61 specific issue, I discussed it with Peter Hutterer. It seems to be that on this hardware, the numlock key doesn't actually send events when the fn is pressed so we have no way of knowing that it is pressed. This was verified via gdb on the xserver. Scroll lock and numlock are shared, so fn has to be pressed to trigger numlock.
So it seems to be either a hardware or kernel bug."
This doesn't seem quite accurate: I do (at least sometimes) see key events for the Fn key. Also, shift+numlock also activates num lock, and shift definitely does show key events.