On Tue, Aug 14, 2012 at 10:31:24AM +0200, Alexis de BRUYN wrote: > On 13.08.2012 23:34, Matthieu Herrb wrote: > > On Sun, Aug 12, 2012 at 10:04:17PM +0200, Alexis de BRUYN wrote: > >> On 11.08.2012 23:33, Alexis de BRUYN wrote: > >> I still have my previous issue, but I have another one : while the > >> in-board display device is actived through my xorg.conf, the udl devices > >> are not working too. > > > > Yes, this is a know issue. The OpenBSD-specific part of Xorg has no > > way to handle a dual-screen setup between udl and one (or more) > > regular VGA card(s) on most architectures. > > Thanks Matthieu for your answer. However can it handle multi-screens > with *only* udl devices (without configuring the regular VGA card in > xorg.conf) ? I didn't succeed.
Right now, I don't see a reason why 2 udl devices wouldn't work, but I'm not sure I ever tried it. > > > Fixing this require quite a bit of worg though. > > Can you tell me a bit more please ? Why it is not supported ? On i386 and amd64, when the X server is talking to a VGA card it bypasses the kernel completely and talks to the hardware directly. When multiple video cards are used, there is still no interactions with the kernel. All interaction is done through one single file descriptor (pointing to the aperture driver xf86(4)). Otoh, drivers like xf86-video-wsudl or xf86-video-wsfb use a specific file descriptor (pointing to the wsdisplay device /dev/tty[CDE..]0) per card. The 2 driver models can currently not co-exist in the server. The current work done upstreams on switching all drivers to KMS (Kernel side Mode Settings) will eventually clean up the current mess. Just don't hold your breath, since porting KMS to OpenBSD is only making very slow progress. > > Regards, > > -- > Alexis de BRUYN -- Matthieu Herrb
