Re: pvfb: Absolute vs relative mouse tracking mystery

[John Haxby <john.haxby@oracle.com>]

  On 04/08/10 01:35, Joshua West wrote:
> Ahh... So then if we get the PVFB going with 1024x768 resolution, 
> instead of wonderful 1990's 800x600, we're all set ;-)
>

Did you ever have one of those plastic pantographs when you were a kid?  
I remember having a couple and they were rubbish, the enlarged (or 
reduced) drawing looked nothing like the original.   The mapping from 
absolute to relative in mousedev has the same sort of problem, although 
if I'm feeling really generous it might just be rounding errors (though 
I doubt it).

> I've been testing with evdev driver as well (Option "Device" 
> "/dev/input/event1" for me), but that has not worked.  I see what 
> you're saying though - I can see two entries in 
> /proc/bus/input/devices, and my mouse handlers are "mouse0 event1 
> ts0", but both the keyboard and mouse physical device is the same: 
> "xen/device/vkbd/0".  And this is all with linux-2.6.18-xen.hg.

Hmm.  It should work.  I don't have a linux-2.6.18-xen.hg handy, but if 
you send me your xorg.conf and /proc/bus/input/devices (off list) I'll 
take a look.

>
> I'm looking forward to your custom RHEL/CentOS driver to get this going.

Sorting it out now.

>
> One last question -- even if using linux-2.6.18-xen.hg, are you saying 
> we still need request-abs-pointer kernel argument?  Wasn't that just 
> to enable absolute pointer mode in the RHEL mouse driver if using RHEL 
> 5.5 and their Xen kernel (looked that way from their patch)?  Or is 
> RHEL's Xorg somehow also looking for this directive?

It's just in the Red Hat/CentOS 5.5 kernels, you don't need it for any 
of the others.  And it's just to get the xenkbd front end to set 
request-abs-pointer in xenstore.  For my money, it would be better to 
have absolute pointers by default and have guests ask for relative ones 
if they really really want them.  I think this was propose a little 
while ago, but I don't recall what happened.

jch