I've recently bought DisplayLink device. According to , it
might/should work under OpenBSD so I gived it a try. My results are:
1) Not detected USB PID - I've added it as new device to kernel's udl
2) Conflict with bulit-in Intel HD graphics card.
I spent some time debugging why xf86-video-wsudl is not detecting my
DL-165 adapter. After downloading xenocara I was debugging wsudl and
what I found:
driver/xf86-video-wsudl/src/wsudl_driver.c:309 calls xf86ClaimFbSlot()
xserver/hw/xfree86/common/xf86fbBus.c:62 checks if pciSlotClaimed is
And, unfortunately, on my platform pciSlotClaimed == 1, because of
intel driver. However, things started to work when before calling
xf86ClaimFbSlot() I've set pciSlotClaimed to 0.
3) UDL device does not get auto-detected
I had to define UDL device manually in xorg.conf and connect screens
using Xinerama to make it working
4) Resolution problems with Intel - maybe because of hacking from point
2 in random situations intel driver fails and messes up resolution on
one of the screens - about 3/4 of screen become unusable. No idea
how to explain it.
What I've found:  - so more or less It will not work, no
way. But under Linux there are no performance issues at all. I can
even play video (but not in fullscreen), 1080p works great. Where's
the bottleneck in OpenBSD? I am not even able to move window on the
desktop smoothly, in idle Xorg process consumes 5-10% of CPU with
peaks up to 40%.
Further informations about my platform:
- Lenovo ThinkPad t420s with Intel i7.
- 2× BENQ G2420HD
- i-tec 2.0 TRIO USB to DVI (DisplayLink DL-165 inside)
Unfortunately, I am really newbie in both OpenBSD and kernel
development, so I am afraid that debugging like this is everything I am
able to. Are there any active developers of wsudl driver? Issues 4 and 5
are fatal to me, I need two displays - do you have any ideas how to move
things forward here?
 - http://www.i-tec-europe.eu/?t=3v=130
 - http://libdlo.freedesktop.org/wiki/
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