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Re: Dell XT2 and Calibration (RHEL6)

 

On 12/05/2010 10:10 PM, Ray Van Dolson wrote:
> Hey all;
> 
> Recently went through a great saga getting the touch screen (don't have
> a stylus) working on a Dell XT2 under RHEL6+errata.
> 
> Huge thanks to Fafux[1] for lots of help.
> 
> My last remaining issue is calibration.
> 
> When I start up X, the touch is nearly unusable.  I have to tap
> multiple times to get clicks to register and the cursor appears nowhere
> near my finger as I drag.
> 
> I'm using 9600/7200 as my BottomX/BottomY values respectively (and have
> also tried 9500 for BottomX) per suggestion.  Really no difference
> though.
> 
> The main thing that _did_ help was this program[2].  After running
> this, everything works _flawlessly_ in the mtview program and much,
> much better in X itself.
> 
> However, the acceleration still seems off -- I'm trying to figure out
> how I should adjust this?  Perhaps via the normal Xorg xset tool?  Why
> would it be flawless in mtview but not in X?

Can you explain more what you mean here? There shouldn't be any pointer
acceleration since the device isn't a touchpad. Where you touch should
be where the pointer is.

> In addition, I'd like to figure out if whatever the n-trig calibtation
> tool does could be done automatically in the driver or in my X
> configuration so I don't have to run this every time I reboot the
> system...

That's odd... I don't think any of us need to run the calibration tool
that often. I've never had to run it on my Dell Studio 17, and I think
Duncan has run it once to fix issues.

I think there are many things that could be done to make this easier,
but it really depends on how bad the problem is :). Our hope was that
having a tool that *may* need to be run once would be good enough. We
don't even package it up in Ubuntu proper. However, we may need to look
into this again.

I worry also about auto-calibration. One isn't supposed to touch the
screen during calibration, and we don't want to flash the screen with
"HANDS OFF!" every time one boots into Ubuntu :).

> Many thanks,
> Ray
> 
> PS: I do hope to write up a HOWTO for all this on RHEL6 and identify
> what things need to be packaged up.

Awesoem! Do note that the driver in Ubuntu 10.10 is vastly different
than what's in the upstream kernel right now. Late in our development
cycle we were basically in an "all hands on deck" mode trying to make
ntrig work well. Thus, the Ubuntu driver has been modified heavily for
Ubuntu.

Henrik Rydberg, the upstream kernel MT maintainer and uTouch team
member, will be working to push things up, but I believe he needs to get
more MT foundational code into the kernel first.

-- Chase



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