Re: Lenovo T16 Gen 3 touchpad/trackpoint problem (7.9/amd64)

Hi Ulf and Kihaguru,

On Sun, Aug 09, 2026 at 01:57:37PM +0200, Ulf Brosziewski wrote:
> I try to summarize what I have read in this thread.  You are dealing with
> two problems, which may be related, or simply co-occur:
> - Inputs from devices that report relative coordinates - that is, the
>   trackpoint, and the touchpad in "non-native" mode - cause cursor jumps
>   (only at the start of a movement, did I get that right?).
> - Occasionally, typing triggers a motion event (I assume that this, in
>   turn, triggers a cursor jump because of the first problem).

That's close to correct, but not quite:
I *only* see jumps when typing.  I.e., just moving my fingers on the
touchpad never triggers a jump.


> it might be useful to start testing with a minimal setup.  You could
> delete or rename your xorg.conf, reboot the laptop, and disable ims and
> pms in the kernel:
> 
> At the boot prompt, enter
>   > boot -c
> and at the UKC prompt:
>   UKC> disable ims
>   UKC> disable pms
>   UKC> quit
> (The changes to the kernel configuration are temporary.)


For my first test I overlooked your suggestion to delete or rename
xorg.conf, and tested using
--- begin /etc/X11/xorg.conf ---
Section "InputClass"
	Identifier "wsmouse touchpad"
	Driver "synaptics"
	MatchIsTouchpad "on"
EndSection

Section "InputDevice"
	Identifier "TrackPoint and buttons"
	Driver "ws"
	Option "Device" "/dev/wsmouse2"
	Option "AutoServerLayout" "true"
EndSection
--- end /etc/X11/xorg.conf ---

The result of rebooting and disabling both ims and pms as you suggest is:
* the touchpad works fine
* the mechanical touchpad buttons don't work (pressing them doesn't seem
  to have any effect)
* clicking anywhere along the bottom of the touchpad produces the same
  actions I have bound to the left touchpad button
* the cursor no longer jumps!!  I've been typing for an hour or so
  (writing & debugging a small perl utility, then writing this message),
  and no jumps at all!!

Next I'll try rebooting and disabling both ims and pms, with xorg.conf
renamed.....

ciao,
-- 
-- "Jonathan Thornburg [remove -color to reply]" <[email protected]>
   he/him; on the west coast of Canada; https://www.bkis-orchard.net/
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