No, I think Thomas is correct that we do need an open() routine, and we
might as well make the NULL case an error. For example, the dummy driver
actually _had_ an open routine, but it was enabled only when compiled as
a module. That's against the ideas of modules - I much prefer it if all
the drivers are the same regardless of whether they are compiled as
modules or not (that way there are no surprises).
pre-2.0.6 should have the dummy driver working again, as well as the
alias setup. Addign an open routine for alias makes sense anyway, in case
we ever want to have that as a module in which case the open routine is
needed for reference counting.
Linus