출처 : http://centos.org/modules/newbb/viewtopic.php?topic_id=12665&forum=39

The Ultranav Trackpoint on Thinkpads has a great middle button scrolling ability. Some distros [read: Ubuntu, openSUSE] have little to no problem configuring it because, unlike Fedora and CentOS, they have decided to keep the /dev/psaux device instead of completely using the /dev/input/ devices. I searched around and could not find a good way to configure the scrolling in CentOS. Finally, I did some detective work and this is what I found. This is using a IBM ThinkPad T42, but should probably work on must UltraNav equipped ThinkPads.

The default CentOS 5 install configures a single input device using the Synaptics driver. This will give you some 99% of the functionality, but will not allow you to configure Trackpoint scrolling. Here is what it looks like.

Section "InputDevice"
Identifier "Synaptics"
Driver "synaptics"
Option "Device" "/dev/input/mice"
Option "Protocol" "auto-dev"
Option "Emulate3Buttons" "yes"
EndSection

What we need to do is have two sections; one for the Synaptics touchpad and another for the Trackpoint. Since /dev/psaux does not exist, we need to find out where the specific touchpad device file is.


[msiner@luigi Desktop]$ cat /var/log/Xorg.0.log | grep Synaptics
(**) |-->Input Device "Synaptics"
(II) Synaptics touchpad driver version 0.14.4 (1404)
(--) Synaptics auto-dev sets device to /dev/input/event1
(--) Synaptics touchpad found
(**) Synaptics: always reports core events
...


Since it is at /dev/input/event1 (use that command on your own machine because yours may be different), we can configure the trackpoint at /dev/input/mice and the touchpad at /dev/input/event1. The last trick we need is to also use the "SendCoreEvents" option to make sure both of them work. Here is my xorg.conf configuration for the device. Notice that I included the ServerLayout section as it had to be changed.

Section "ServerLayout"
Identifier "Default Layout"
Screen 0 "Screen0" 0 0
InputDevice "Keyboard0" "CoreKeyboard"
InputDevice "Trackpoint"
InputDevice "Synaptics"
EndSection

...

Section "InputDevice"
Identifier "Trackpoint"
Driver "mouse"
Option "CorePointer"
Option "Device" "/dev/input/mice"
Option "Protocol" "ImPS/2"
Option "ZAxisMapping" "4 5"
Option "EmulateWheel" "true"
Option "EmulateWheelButton" "2"
EndSection

Section "InputDevice"
Identifier "Synaptics"
Driver "synaptics"
Option "SendCoreEvents" "true"
Option "Device" "/dev/input/event1"
Option "Protocol" "auto-dev"
Option "Emulate3Buttons" "yes"
Option "SHMConfig" "on"
EndSection

...

This setup has worked for me and I hope this post helps somebody else who is having trouble with this or had just accepted the sad fate of not having Trackpoint scrolling. Some of you might have figured this out already, but I cound not find any info through Google or even ThinkWiki.