RandR isn't exactly verbose in specifying, what an output actually is.
So far, two interpretations have been used, with one limitation or
another.
Most drivers interpret outputs to be connectors (a), so they have
outputs named like
VGA-1
DVI-1
radeonhd instead uses signal routes as outputs (b), so the same set as
above is specified as 3 outputs, named
VGA-1
DVI-I_1/analog
DVI-I_1/digital
The advantage of a) is that this is much more user friendly due to the
short names. The disadvantages (and main reason for radonhd to be
implemented differently) are
1) that there is little metainformation on the connectors
2) you can (theoretically) drive both the analog and digital lines on a
DVI port, even with different signals - which cannot be realized with
scheme a) at all
The disadvantage of b) is mainly that the names are awkward to use, and
having the same connector listed twice leads to confusion.
Regarding a)'s disadvantages 1) can be sort-of removed by presenting the
meta information over properties (something to be standardized with
RandR 1.3), and 2) is theoretically possible, but typically
impracticable, and also not really supported (there's only one DDC line
per DVI connector). DMS-59 connectors would fit in this scheme, but are
already represented as two DVI connectors nowadays.
So the question is with the property system in place (some corrections
need to be applied) is whether to keep the old style, or whether to
convert to the apparently standard style other drivers have used so far.
I remember a discussion with Alex Deucher, after which both of us were
basically convinced, that the solution of the other one (respectively)
is the right one :-P
I'd like to ask for reasons for one approach or the other, and for the
general feeling about this issue. Maybe we have a strong majority for
one of the two solutions. Somehow, I guess we will be closer to 50:50,
though :-]
So please post your conclusion, especially if you can back it up with
experience or configurations that would work well in one of the
scenarios, but not in the other.
Thanks
Matthias
--
Matthias Hopf