Accepted xresprobe 0.4.24ubuntu1 (source)

[Matt Zimmerman]

On Thu, Mar 08, 2007 at 12:14:05PM +0200, Timo Aaltonen wrote:
> On Wed, 7 Mar 2007, Matt Zimmerman wrote:
> > Does this provide us with any useful information?  Does the VESA BIOS
> > accurately report the size of an attached LCD?
> 
> No it doesn't, but the server autoprobes the best values it can use.

How does it probe this when it's using the VESA driver, if not by way of the
BIOS?

> > No, I don't think it can.  The beta freeze is next week, and the beta
> > release the week after.  I don't think this can be credibly tested before
> > then.  We simply won't know whether it breaks too much until huge numbers of
> > people try the beta.
> 
> That's correct.. we can narrow the change:
> 
> >> The old version probes with a config that has a 'Mode "1024x768"' set,
> >> which means that the string I'm trying to match with vesa would be just
> >> that (->no progress).
> >
> > There were no bug numbers included in the changelog, so it isn't clear what
> > problem you're attempting to solve.  Perhaps if you discuss it here on the
> > list, we can come to a consensus about the best way to proceed.
> 
> Well, we can make it to only use autoprobing when the driver is vesa. 
> Like this (xprobe.sh):
> 
> if [ "$DRIVER" = "vesa" ]; then
>    /usr/bin/Xorg :67 -ac -probeonly -logfile "$TMPLOG" > "$TMPOUT" 2>&1
> else
>    /usr/bin/Xorg :67 -ac -probeonly -logfile "$TMPLOG" -config "$TMPCONF" > "$TMPOUT" 2>&1
> fi
> 
> Note that all of this is only for laptop owners which have to use the 
> vesa-driver (newer ATI chips, for instance). If it's not a laptop, a 
> different method is used to probe the resolution (=ddcprobe).

We should only be changing this part of the infrastructure at this point in
the release cycle in very well-defined and predictable ways, and hardware
detection is especially tricky.  The change should definitely be limited
to cases known to be handled incorrectly if that is possible, and they
should also be scrutinized to ensure that they're improving the situation.

Again, can you describe the problem this change is meant to solve?  Are
there bug reports which are relevant to this problem?  How did you decide to
make this change?

-- 
 - mdz