Subject: Re: making tpcalib MI
To: TAKEMURA Shin Takemura <>
From: Matthew Orgass <>
List: tech-kern
Date: 05/30/2004 21:50:00
On 2004-05-30 wrote:
> Please note that a root file system might be shared by two or more
> machines if root device is removable. For example, I have dozen MIPS
> base handhelds with touch panels and only one micro drive for root FS.
> Ideally, the GETID returns GUID (global unique ID) for the touch
> panel. The current implementation returns magic string, which contains
> model name and serial number. If serial number is not available on the
> machine, zero will be used instead. That is the reason the GETID seems
> to just returns model name.

  What happens if you want to share two of the same machine with different
calibrations or use multiple calibrations on a single machine?  What if
you want to change more than just calibration between the different
models?  I think machine selection for calibration should be done in rc
files by sysctl values, not a special case for calibration.  Currently,
nothing has a real serial number.  Even if it did, unless it is a touch
panel specific serial number it should IMO be available and used as a
sysctl value so that other aspects of system configuration can be selected
on it as well.  If there are touch panel specific serial numbers available
this could be provided through GETID and made available in userland by
wsconsctl so that it could also be used generally if desired.  Currently,
use of system model instead of driver identifier would make a touch panel
specific serial number not unique, so I guess you mean system serial
number.  I don't think this information belongs in a mouse ioctl.  If
tpctl uses a user supplied name to select the calibration to use,
compatability with existing calibration files can be maintained by
supplying the same value that is currently used by means of sysctl. I
don't think this needs to be changed immediatly, but I do think the
current system is broken and should be changed at some point (and sooner
would likely be easier than later).

Matthew Orgass