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My Thinkpad T420 has had problems with recognizing the touchpad since I updated to Ubuntu 14.04. Immediately after logging in, it can recognize the touchpad, and all is fine. However, if I suspend, the touchpad stops being recognized about 30 seconds-1 min after resuming and rarely gets recognized again unless I log out and back in or restart the computer. But sometimes it can unexpectedly start working for a while--it's intermittent and hard to say exactly when it goes out. When I say it stops being recognized, I mean it stops showing up in "xinput list." When the touchpad is working, I get this output:

⎡ Virtual core pointer                      id=2    [master pointer  (3)]
⎜   ↳ Virtual core XTEST pointer                id=4    [slave  pointer  (2)]
⎜   ↳ Logitech USB Receiver                     id=9    [slave  pointer  (2)]
⎜   ↳ SynPS/2 Synaptics TouchPad                id=12   [slave  pointer  (2)]
⎜   ↳ TPPS/2 IBM TrackPoint                     id=13   [slave  pointer  (2)]
When not working, I get this output:
⎡ Virtual core pointer                      id=2    [master pointer  (3)]
⎜   ↳ Virtual core XTEST pointer                id=4    [slave  pointer  (2)]
⎜   ↳ Logitech USB Receiver                     id=9    [slave  pointer  (2)]

The Logitech USB Receiver is my external mouse, which works fine. Whenever the touchpad is not recognized, the Thinkpad Trackpoint also goes out simultaneously, which is really mysterious.

Any idea what the problem could be? Thanks.

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  • Not an answer to your question, but it may be quicker to try this as root, modprobe -r psmouse and then modprobe psmouse. Might be quicker than reboot to get working again when it stops on you.
    – geoffmcc
    Commented Jan 1, 2015 at 19:20
  • I'm familiar with this fix. Sometimes it works, but more often than not it doesn't. Thanks though.
    – sgbowen
    Commented Jan 1, 2015 at 23:19
  • You can try the linked answer regarding Dell Inspiron.
    – Pilot6
    Commented May 15, 2015 at 14:37

1 Answer 1

Reset to default
0

I found a fix that works for my computer.

In terminal, 

sudo vim /etc/modprobe.d/blacklist.conf

Enter a new line

blacklist i2c_hid

Save and reboot

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