xrandr providers and offloading to displaylink usb card

[Sam Lanning]

On 07/01/13 07:03, Dave Airlie wrote:
> On Mon, Jan 7, 2013 at 10:23 AM, Sam Lanning <sam at samlanning.com> wrote:
>> Hi There,
>>
>> I have a displaylink usb adapter which i have been trying to get working
>> with my setup for a while.
>>
>> when i run
>>
>>> xrandr --listproviders
>> i get the output
>>
>>> Providers: number : 2
>>> Provider 0: id: 106 cap: 0xb, Source Output, Sink Output, Sink Offload
>>> crtcs: 2 outputs: 4 associated providers: 1 name:Intel
>>> Provider 1: id: 68 cap: 0x2, Sink Output crtcs: 2 outputs: 3 associated
>>> providers: 1 name:modesetting
>> and after running the command
>>
>>> xrandr --setprovideroutputsource 68 106
>> I get 3 new outputs added to xrandr:
>>
>>> LVDS-0 disconnected
>>> VGA-0 disconnected
>>> HDMI-0 disconnected
> that doesn't seem like displaylink to me, the driver will never create
> LVDS outputs.
>
> Might want to confirm with a copy of the log file.
>
> Dave.
Hey,

It's been a while (busy with academia) but now i have some time to try
and get this working again.

I'm running on a laptop with optimus, i believe that the second provider
listed above is actually my nvidia card. Now i am aware that the hdmi
port is connected only to the nvidia card, this would match up nicely
with what i have above, i.e. i activated my nvidia card, hence
activating my hdmi output, along with the outputs of the other display
ports (which are connected to both cards)

So it seems my problem at the moment is this:

I have (what i believe to be) the latest display link drivers installed.
When i plug in my usb gpu, i have a new device listed under lsusb:

> Bus 002 Device 008: ID 17e9:01d7 DisplayLink

And a new corresponding framebuffer device /dev/fbx appears (although
interestingly it is fb1 sometimes if plugged in at boot).

So my question is, why is it not appearing after calling xrandr
--listproviders (which shows only my integrated and nvidia cards). Any
help would be greatly appreciated.

Many Thanks,
Sam.