Ubuntu – Touchpad not recognized after suspend (Ubuntu 14.04, Thinkpad T420)

14.04mousesuspendthinkpadtouchpad

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.

Best Answer

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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Ubuntu – How to config Trackpoint + Synaptics touchpad only enable clicks on Linux (Ubuntu)

Well, this is not the direct answer, but a suggestion and examples. If you run xinput, you will get list of your devices. Then run xinput list-props $id where $id is your touchpad id in the list.

You will have a list of options like this:

$ xinput list-props 13
Device 'SynPS/2 Synaptics TouchPad':
    Device Enabled (135):   1
    Coordinate Transformation Matrix (137): 1.000000, 0.000000, 0.000000, 0.000000, 1.000000, 0.000000, 0.000000, 0.000000, 1.000000
    Device Accel Profile (268): 1
    Device Accel Constant Deceleration (269):   2.500000
    Device Accel Adaptive Deceleration (270):   1.000000
    Device Accel Velocity Scaling (271):    12.500000
    Synaptics Edges (292):  1765, 5371, 1637, 4453
    Synaptics Finger (293): 25, 30, 0
    Synaptics Tap Time (294):   180
    Synaptics Tap Move (295):   234
    Synaptics Tap Durations (296):  180, 180, 100
    Synaptics ClickPad (297):   1
    [...]

You can change all of these on-the-fly with xinput set-prop $id $propId $value where $id is the device id, $propId is property id in brackets and $value is what you want it to be. For example:

xinput set-prop 13 135 0 sets Device Enabled (135) to 0 and this will disable the touchpad.

You will need descriptions of properties and a way to make your changes permanent. Descriptions can be found in man synaptics, but wait, they are in another cryptic format! Let's see why.

To make changes permanent, you need to create conf file in /etc/X11/xorg.conf.d, for example 30-tochpad.conf with contents like these:

    Section "InputClass"  # you can read more in `man xorg`
            Identifier "all touchpads"  # just a name for this config
            MatchIsTouchpad "on"  # enables this config for all detected touchpads
            Driver "synaptics"  # enables synaptics-specific options below

            # This will disable the device
            #Option "Ignore" "1"

            # There are options that are generic for input-devices or mouse-like devices, see `man evdev`:
            Option "ButtonMapping" "0 0 0 0 0 0 0"  # i disabled all buttons here, for example

            # Here go options from `man synaptics`
            Option "VertTwoFingerScroll" "1"
            Option "HorizTwoFingerScroll" "1"
            Option "PalmDetect" "1"
            Option "ClickPad" "0"                
            # ...etc...
    EndSection

So, man synaptics describes options for xorg.conf and tells how they correspond to xinput list-props output.

PS. I tried to configure trackpoint on my ThinkPad X220 to have only two-fingers-scroll enabled, without clicks or mouse movement. I failed. Maybe you will manage to do what you want (there was an option to disable everything but clicks, maybe Synaptics Off).

Sources, more examples and unicorns:

https://wiki.ubuntu.com/X/Config/Input

https://wiki.archlinux.org/index.php/Touchpad_Synaptics

Best Answer

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Ubuntu – How to config Trackpoint + Synaptics touchpad only enable clicks on Linux (Ubuntu)

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