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Date: Tue, 17 Feb 2015 00:05:26 +0000
From: Gary Palmer <gpalmer@freebsd.org>
To: Hans Petter Selasky <hps@selasky.org>
Subject: Re: Pluggable frame buffer devices
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Cc: freebsd-current@freebsd.org, Shawn Webb <lattera@gmail.com>
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On Mon, Feb 16, 2015 at 06:10:22PM +0100, Hans Petter Selasky wrote:
> On 02/16/15 16:39, Shawn Webb wrote:
> > On Sunday, February 15, 2015 11:14:47 PM Hans Petter Selasky wrote:
> >> Hi,
> >>
> >> I've added support for USB display link adapters to FreeBSD-11-current,
> >> but the kernel panics once "vt_fb_attach(info)" is called from
> >> "fbd_register(struct fb_info* info)" when the USB device is plugged or
> >> udl.ko is loaded. Is this a known issue?
> >>
> >> REF: https://svnweb.freebsd.org/base/head/sys/dev/usb/video/udl.c
> >>
> >> --HPS
> >
> > I personally can't answer your question. But I'd love to help test this,
> > especially since Haswell graphics isn't supported, yet, and my laptop is
> > running Haswell. What would be a good USB display device to buy to help test
> > this awesome work out?
> 
> Hi Shawn,
> 
> I think any USB device that uses the brand name "DisplayLink" will work.

Hi HPS,

I thought the later generations, especially the ones with USB3 support,
used a propretary encryption between the host and the adapter that was
not currently supported by any F/OSS operating system?  

If you look on the DisplayLink forums there are angry threads about
the lack of Linux support for the later generation dongles.

e.g.

http://displaylink.org/forum/showthread.php?s=77a3ad0ad0f21031f0996325f249f584&t=61689

(there's a much longer thread somewhere which is more angry, but I've lost
 the link)

Regards,

Gary