Arch Linux

meta_inf

Member

Registered: 2013-05-06

Posts: 5

Latitude E7440: TrackPoint occasionally gets out of control

Hi,

I've been using Arch on this laptop for months and the trackpoint occasionally gets out of control when moving cursor with it.

In a common scenario, the cursor accelerates abnormally and generates random clicks without my action. The 'xinput test' command shows that unmatched button release event is triggered.

Configuration of the trackpoint is listed below.

~ % xinput list-props 12                                                                                                  [0]
Device 'DualPoint Stick':
        Device Enabled (134):   1
        Coordinate Transformation Matrix (136): 1.000000, 0.000000, 0.000000, 0.000000, 1.000000, 0.000000, 0.000000, 0.000000, 1.000000
        Device Accel Profile (256):     0
        Device Accel Constant Deceleration (257):       1.000000
        Device Accel Adaptive Deceleration (258):       1.000000
        Device Accel Velocity Scaling (259):    10.000000
        Device Product ID (252):        2, 8
        Device Node (253):      "/dev/input/event12"
        Evdev Axis Inversion (260):     0, 0
        Evdev Axes Swap (262):  0
        Axis Labels (263):      "Rel X" (144), "Rel Y" (145)
        Button Labels (264):    "Button Left" (137), "Button Middle" (138), "Button Right" (139), "Button Wheel Up" (140), "Button Wheel Down" (141)
        Evdev Middle Button Emulation (265):    0
        Evdev Middle Button Timeout (266):      50
        Evdev Third Button Emulation (267):     0
        Evdev Third Button Emulation Timeout (268):     1000
        Evdev Third Button Emulation Button (269):      3
        Evdev Third Button Emulation Threshold (270):   20
        Evdev Wheel Emulation (271):    1
        Evdev Wheel Emulation Axes (272):       0, 0, 4, 5
        Evdev Wheel Emulation Inertia (273):    10
        Evdev Wheel Emulation Timeout (274):    200
        Evdev Wheel Emulation Button (275):     2
        Evdev Drag Lock Buttons (276):  0

Thanks in advance.

gtrak

Member

Registered: 2014-09-17

Posts: 1

Re: Latitude E7440: TrackPoint occasionally gets out of control

This happens to me regularly on ubuntu 14.04 with a Dell e7440 ever since I got it.  Looks like a software bug.  I'd be happy to help debug any way possible? (past arch user)

Specifically, I'd describe the behavior as the cursor jumping around incredibly quickly while randomly clicking the middle button, resulting in spammed pastes.  Clicking the middle button myself usually gets it unstuck.  The touchpad is disabled, and I use an external mouse at work with no problem.

Last edited by gtrak (2014-09-17 12:50:14)

gps1539

Member

From: Los Gatos, CA

Registered: 2013-11-06

Posts: 134

Re: Latitude E7440: TrackPoint occasionally gets out of control

Does this sound to be the same issue? If so a fix may be coming.

https://bugzilla.redhat.com/show_bug.cgi?id=1145954

BTW.
At my new company I have a choice of macbook or Dell E7440. Apart from the trackpoint issue, would you recommend the Dell?

gps1539

Member

From: Los Gatos, CA

Registered: 2013-11-06

Posts: 134

Re: Latitude E7440: TrackPoint occasionally gets out of control

Any fixes for this?

TE

Member

Registered: 2014-06-21

Posts: 78

Re: Latitude E7440: TrackPoint occasionally gets out of control

I "fixed" this problem for the most part by forcing the E7440 trackpad into a dumber mode (you don't get the dual-finger stuff) like so:

/etc/modprobe.d/touchpad.conf

options psmouse proto=imps

Unload/reload the psmouse module (w/ modprobe, or just reboot) and the jumping randomly random-key input goes away for the most part. Every once in awhile I still get a "stuck" key (typing, press 'x' and start getting 'xxxxxxxxxxxxxxxxxxxxxxxxxx....' until you force a backspace key).