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Re: Dell XT2 and Calibration (RHEL6)

 

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've run it on your studio 17 (just to test the routine, not because it was responding poorly), but that's besides the point.

Ray, please confirm the frequency and conditions of your recalibrations. If you have to calibrate on every boot, but its stable for long periods during a normal boot then something is definitely very strange and I'm going to ask you to collect various samples for analysis.


There are a number of factors which I've specifically seen effect the rate of decay. Off the top of my head:
- device power supply
- grounding
- temperature
- humidity (and ambient static)

I have also suspected imperfect firmware installs might occur, but that's a hard one to verify.

You also mentioned having a newer firmware than anyone else has reported. So you may have the honor of discovering new bugs :)

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.

Releasing the kernel calibration code is still on my todo list. Once in place it will provide a simpler approach. If you think such a tool is a priority, then I'll clean that up and ask you (Chase) to look it over.

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 :).

This has come up in discussion several times. I still don't have a sure answer to whether the ntrig calibration is incremental/cumulative or if it gets completely reset every time you run it. My experience suggests its incremental, in which case contact during a short partial calibration would mostly result in a very slight alteration of sensitivity and only where the user is touching. It think there are many opportunities to freshen up calibration slightly. For example, when the lid is closed and the machine is either going to sleep or blank the screen, or after the machine is idle for a while.

Anyway, that's another conversation. Incremental calibration is likely not relevant if the device is completely messed up on every boot.


Rafi



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