[Libdlo] Only greenscreen ----searching for suggestions a long time

[Mike Jager]

On 06/02/10 13:57, Bernie Thompson wrote:

> Anyone else having any success with extended desktop scenario on 
> Ubuntu 9.10? Any definitive instructions?

Sort of.

I've got 2 HP DL adapters attached to my Dell Vostro 1310 for use when 
I'm at home. I'm using the udlfb driver that's bundled with the Ubuntu 
9.10 kernel (2.6.31-17-generic). This gives me the green screen as soon 
as the DL adapters are attached.

This is combined with udev to ensure that the FB devices get consistent 
naming under /dev:

cat /etc/udev/rules.d/99-displaylink.rules
ATTRS{product}=="HP USB Graphics Adap", ATTRS{serial}=="101050", 
SYMLINK="fbhp0"
ATTRS{product}=="HP USB Graphics Adap", ATTRS{serial}=="101217", 
SYMLINK="fbhp1"

I'm using version 0.3 of xf86-driver-displaylink - the one bundled in 
udlfb-0.2.3_and_xf86-video-displaylink-0.3.tar.gz. Prior to compilation, 
I comment out line 548 of src/displaylink.c, which is 
"xf86CrtcScreenInit (pScreen);". This is as per the suggestion in 
http://lists.freedesktop.org/archives/libdlo/2009-June/000234.html to 
disable RandR.

This driver then gets installed (usual ./configure ; make ; sudo make 
install) into /usr/local/lib/xorg/modules/drivers. I can't remember 
exactly what packages I had to install prior to compilation, but from 
memory there was nothing out of the ordinary - xorg-dev, libusb-dev, 
build-essential, and their dependencies.

My xorg.conf looks like this:

Section "Files"
         ModulePath      "/usr/lib/xorg/modules"
         ModulePath      "/usr/local/lib/xorg/modules"
EndSection

Section "ServerFlags"
	Option		"DontZap" "off"
	Option		"EnableRandR12" "false"
EndSection

Section "Device"
	Identifier	"dl0"
	Driver		"displaylink"
	Option		"fbdev" "/dev/fbhp0"
EndSection

Section "Device"
	Identifier	"dl1"
	Driver		"displaylink"
	Option		"fbdev" "/dev/fbhp1"
EndSection

Section "Monitor"
	Identifier	"philips0"
EndSection

Section "Monitor"
	Identifier	"philips1"
EndSection

Section "Screen"
	Identifier	"screen0"
	Device		"dl1"
	Monitor		"philips0"
	SubSection "Display"
		Depth	24
		Modes	"1280x1024"
	EndSubSection
EndSection

Section "Screen"
	Identifier	"screen1"
	Device		"dl0"
	Monitor		"philips1"
	SubSection "Display"
		Depth	24
		Modes	"1280x1024"
	EndSubSection
EndSection

Section "ServerLayout"
	Identifier	"multihead"
	Screen		0 "screen0" 0 0
	Screen		1 "screen1" LeftOf "screen0"
	Option		"Xinerama" "on"
	Option		"Clone" "off"
EndSection

All of this gives me something that's definitely usable on a day-to-day 
basis. It doesn't win any awards at displaying full-screen video, but it 
meets my requirements. I couldn't get my laptop screen (Intel graphics) 
working for a triple-head setup in Ubuntu 9.04, and I haven't bothered 
trying for 9.10. I use vbetool to turn off my laptop's screen while it's 
"docked" to the external monitors.

I may have butchered something horribly in getting this working, but 
like I say, it Works For Me. Feedback's welcome, and I hope this helps 
someone else get their DL adapters working. Thanks to the various people 
that have gotten the Linux DL support to this state, and long may it 
continue!

-Mike