Input

Revision 18 as of 2011-05-20 07:23:16

Clear message

Ubuntu supports input-hotplug. With this functionality, it's likely that you won't need to do any configuration at all to make your devices work, assuming they're recognized and set up by the kernel. However, if you do need to do adjust things, read on.

Dynamic Input Configuration with xinput

The xinput command line tool can be used for some on-the-fly configuration adjustments.

To view a listing of the input devices X sees, run: 

$ xinput list
⎡ Virtual core pointer                          id=2    [master pointer  (3)]
⎜   ↳ Virtual core XTEST pointer                id=4    [slave  pointer  (2)]
⎜   ↳ SynPS/2 Synaptics TouchPad                id=8    [slave  pointer  (2)]
⎜   ↳ Logitech USB Receiver                     id=9    [slave  pointer  (2)]
⎣ Virtual core keyboard                         id=3    [master keyboard (2)]
    ↳ Virtual core XTEST keyboard               id=5    [slave  keyboard (3)]
    ↳ Power Button                              id=6    [slave  keyboard (3)]
    ↳ Lite-On Technology Corp. ThinkPad USB Keyboard with TrackPoint    id=7    [slave  keyboard (3)]

Individual devices can be queried for more details by using the numerical id or the name: 

$ xinput query-state 9
2 classes :
ButtonClass
        button[1]=up
        button[2]=up
        button[3]=up
        button[4]=up
        button[5]=up
        button[6]=up
        button[7]=up
        button[8]=up
        button[9]=up
        button[10]=up
        button[11]=up
        button[12]=up
        button[13]=up
        button[14]=up
        button[15]=up
        button[16]=up
        button[17]=up
        button[18]=up
        button[19]=up
        button[20]=up
        button[21]=up
        button[22]=up
        button[23]=up
        button[24]=up
ValuatorClass Mode=Relative Proximity=In
        valuator[0]=66
        valuator[1]=925

xinput can also be used to alter the button mappings on mice and adjust the acceleration and feedback settings.

Different input drivers may also expose arbitrary properties for applications to set. Synaptics touchpads are particularly configurable like this, but other devices have some more general properties. 

$ xinput list-props 8
Device 'SynPS/2 Synaptics TouchPad':
        Device Enabled:         1
        Synaptics Edges:                1632, 5312, 1575, 4281
        Synaptics Finger:               25, 30, 256
        Synaptics Tap Time:             180
        Synaptics Tap Move:             220
        Synaptics Tap Durations:                180, 180, 100
        Synaptics Tap FastTap:          0
[...]

$ xinput set-int-prop 8 "Device Enabled" 8 0
$ xinput list-props 8
Device 'SynPS/2 Synaptics TouchPad':
        Device Enabled:         0
        Synaptics Edges:                1632, 5312, 1575, 4281
        Synaptics Finger:               25, 30, 256
        Synaptics Tap Time:             180
        Synaptics Tap Move:             220
        Synaptics Tap Durations:                180, 180, 100
        Synaptics Tap FastTap:          0
[...]

Input Configuration with InputClass sections

TODO

Example: Disabling middle-mouse button paste on a scrollwheel mouse

Scrollwheel mice support a middle-button click event when pressing the scrollwheel. This is a great feature, but you may find it irritating. Fortunately it can be disabled.

First, you need to know the id of the mouse, like this: 

$ xinput list | grep 'id='

"Virtual core pointer"  id=0    [XPointer]
"Virtual core keyboard" id=1    [XKeyboard]
"AT Translated Set 2 keyboard"  id=2    [XExtensionKeyboard]
"Macintosh mouse button emulation"      id=3    [XExtensionPointer]
"Logitech USB-PS/2 Optical Mouse"       id=4    [XExtensionPointer]

My mouse has the Logitech logo printed on it, so I gather I need the last entry.

I can view the current button mapping thusly: 

$ xinput get-button-map 4

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 10

Really, only the first three numbers have meaning for me. They represent the left, middle, and right mouse buttons. 

$ xinput get-button-map 4

I can turn the middle mouse button off by setting it to 0: 

$ xinput set-button-map 4 1 0 3

Or I can turn the middle-mouse button into a left-mouse button by setting it to 1: 

$ xinput set-button-map 4 1 1 3

To make this set on a per-user basis, I can plug that line into my ~/.xstartup or other init file. It can also be done via configuring a matching InputClass section on xorg.conf.

Troubleshooting

Custom settings are restored to default when a device is hotplugged, so if you mess up mouse button behavior just unplug it and plug it back in. No need to reboot. Wink ;-)

Contributed Documentation

The following documentation was provided by various people in the past. Generally, much of it was written for pre-InputHotplug X, so may or may not still work in Intrepid.

Keyboard Config

Mouse Config

Tablet Config

Touchpad Config

Game Controller Config