[lug] X11 mouse config, ExplorerPS/2 protocol?

Matt Thompson thompsma at jilau1.colorado.edu
Sat Feb 17 12:48:46 MST 2007

The heavens stretched forth and D. Stimits decreed the following on or 
about 2/17/2007 12:03 PM:
> ...
>> This is what I added to xorg.conf for mine.  (And then you add EvMouse
>> as an input device in the ServerLayout.)
>> Section "InputDevice"
>>        Identifier  "EvMouse"
>>        Driver      "evdev"
>>        Option      "evBits" "+0-2 -3"
>> EndSection
>> The evBits tells the driver what capability bits to match on.  That's
>> how it knows what's a mouse and what isn't.  This reads the value that
>> you can see in /sys/class/input/input*/capabilities/ev
> I'm trying to get this working, so far I have not. I belive the xorg 
> server version 6.8.2 is supposed to support the event interface, but it 
> might be different from the more current versions. I updated the kernel 
> to the most recent FC4 kernel, 2.6.17-1.2142, and I now have /dev/input/ 
> files event0 (the keyboard) through event5. It appears though that both 
> event1 and event2 are the usb receiver for this one mouse...apparently 
> the usb receiver for the mouse has two event streams. One of those, from 
> the /sys/.../capabilities/ev file shows value "7" (event1), the other 
> has value "f" (event2). Is there any clue I can get from decoding the 
> hex "7" or "f" bits? Why two event streams? I can guess that perhaps the 
> mouse uses a separate set of events for reporting connect, disconnect, 
> and battery status, but I don't know...and if so, which stream is the 
> right one for the mouse? Is there a mapping of this value to the evBits, 
> which would make me need to modify option evBits?

In my evdev config, I don't identify on the evBits thing.  I pick 
another udev property to focus on.  I usually go for the product:

Section "InputDevice"
         Identifier  "Intellimouse"
         Driver      "evdev"
         Option      "Device" "/dev/input/event2"
         Option      "product" "008c"
         Option      "CorePointer"
         Option      "Buttons" "7"
         Option      "ZAxisMapping" "6 7 5 4"
         Option      "Emulate3Buttons" "no"

Now, this isn't the best way to do evdev.  If the mouse ever moved USB 
ports, the eventN would probably changes.  But I didn't want to do all 
the udev rule writing jazz.


Time's Person of the Year, 2006
    Matt Thompson -- http://ucsub.colorado.edu/~thompsma/
    440 UCB, Boulder, CO  80309-0440
    JILA A510, 303-492-4662

More information about the LUG mailing list