linksys kvm usb ps2 adaptors and wild mouse pointer

[Scot L. Harris]

On Sat, 2004-09-11 at 23:56, John McBride wrote:
> Some of our kvms, notably linksys, started having real problems with FC2 
> as soon as people started plugging in wireless mice (usually the 
> Microsoft Explorer  wireless mouse). They are using the little usb to 
> ps2 adapters to do this. The mouse just goes crazy in console/gpm 
> (runlevel 3) or X, jumping all over the screen, issuing wild text 
> commands to the command prompt, etc.
> 
> I found the fix over on linuxquestions.org. There is a kernel option to 
> add to /etc/grub.conf:
> psmouse.proto=imps
> (also "bare" or "exps", possibly others).
> 
>  From what I can see:
> "bare" provides a generic 2 button mouse, with 3rd button emulation.
> "imps" lets the explorer wheel act like a third button.
> "exps" should enable the wheel, but actually left the thing hosed (as 
> before).
> 
> On a couple machines, after adding this boot option, I had to run 
> system-config-mouse to set up the mouse, then move the 
> /etc/X11/xorg.conf and run system-config-display under X to get 
> everything cleaned up. Console mode (runlevel 3) was very useful for 
> testing though.
> 
> While I was fooling around with the boot options on one FC2 box, I used 
> Windows 2K on another port. This was a little interesting--the green 
> light on the wireless mouse receiver blinks when changing ports, and 
> also when W2K was just about to launch the greeter, during bootup, right 
> when the display blanks. They are resetting the mouse, I think, while 
> going graphical.
> 
> I've noticed the green light blinks when linux boots, once, but very 
> early on. Right around the first ACPI probes. The mouse driver must be 
> setting up for "exps" and that's borked somehow--exps breaks the 
> explorer mouse, at least with this hardware configuration. If the mouse 
> is plugged directly into the ps2 port, it is fine, so it's a 
> combination/stack of hw causing this.
> 
> Restarting gpm does not blink the light, and I didn't see it blink while 
> starting or running X either. I wonder...is there a way to reset the 
> mouse in FC2, such that the light blinks? I ask because after switching 
> between ports for 20 minutes or so, trying to debug this while doing web 
> searches, I saw the mouse freeze under W2K for a second, and then then 
> the receiver light blinked. Could it be that somehow MS is detecting 
> that the mouse is haywire, freezing the cursor by ignoring it, and then 
> resetting the mouse? What an awful thing for software to go through, but 
> with this particular hw stack maybe such a thing is necessary?
> 
> Regards,
> John

There have been a number of threads concerning mice and KVM problems. 
The fix you found has worked for many people.  There was one thread that
discussed a patch that needed to be tested.  I believe that patch looked
for odd values (which sounded like it caused the wild movements) and
reset the mouse.  I do not remember reading any results of this patch
being used.  Check back about 2 or 3 months in the archives for that
discussion.

-- 
Scot L. Harris
webid at cfl.rr.com

A man of genius makes no mistakes.
His errors are volitional and are the portals of discovery.
		-- James Joyce, "Ulysses"