[Libdlo] Testing a Displaylink adapter. Works with custom driver, but not with standard "fbdev" ?

[ericf at operamail.com]

Hello,

I just got an offer to buy a barely used DisplayLink USB to DVI adapter
[Pluggable Model UGA-2K-A] at < 1/2 off.  Being cheap, I'm interested
:-D

Before I shell out for it I'm testing it.  Bunch of stuff doesn't seem
to work quite right with it.  Probly config. But could be useful as a
backup to have lying around. Just wanted to clear one thing up first.

I'm running a Linux v3.1.0 64-bit kernel.  It looks like the "udlfb"
kernel driver this needs is included with the kernel's modules.  But
which X11 driver do we have to use for this thing?

I tried it with the "fbdev" driver that comes with the distro, setting
it in my xorg.conf, but I just get a black screen when I "startx".

I got the source for a "displaylink" driver from a repo at the vendor's
site [http://git.plugable.com/webdav/xf-video-udlfb/] and built it.  If
I swap the "displaylink" driver in place of the "fbdev" driver I
eventually get my X desktop to display.

I thought these DisplayLink adapters were supposed to be supported in
current kernels if you just use the "fbdev" driver the kernel comes
with.

Do I have to depend on this non-standard X driver and build it every
time I upgrade the kernel to use this adapter?

Eric