Samsung SyncMaster U70

[bab1ch]

Hi,

I'm trying to get SyncMaster U70 working with Manjaro distribution, and I have managed to do so once by following Arch DisplayLink Wiki (https://wiki.archlinux.org/index.php/DisplayLink). With some messing and USB reconnect xrandr --listproviders returned 2 providers and it worked well until reboot. I couldn't make it work again since. If I try to reload the udl module, machine often hangs. I'm not sure if U70 is DL-1xxx device?

/etc/modprobe.d/blacklist.conf
blacklist udlfb

uname -r
4.10.12-1-MANJARO

lsusb
Bus 001 Device 002: ID 17e9:0103 DisplayLink

lsmod | grep udl
udl 28672 0
drm_kms_helper 126976 2 udl,radeon
drm 303104 9 udl,radeon,ttm,drm_kms_helper
usbcore 208896 9 udl,uvcvideo,usbhid,ehci_hcd,ohci_pci,xhci_pci,ohc i_hcd,xhci_hcd,ehci_pci

dmesg | grep udl
[ 13.113255] [drm:udl_driver_load [udl]] *ERROR* Unrecognized vendor firmware descriptor
[ 13.272194] udl 1-1:1.0: fb1: udldrmfb frame buffer device
[ 13.272209] [drm] Initialized udl on minor 1
[ 13.272261] usbcore: registered new interface driver udl

xrandr --listproviders
Providers: number : 1
Provider 0: id: 0x54 cap: 0xf, Source Output, Sink Output, Source Offload, Sink Offload crtcs: 2 outputs: 3 associated providers: 0 name:ATI RV730 PRO [Radeon HD 4650] @ pci:0000:01:00.0

[bab1ch]

So the problem is that udl module is loaded to soon during boot and display is not recognized.
Solution is to blacklist the module:

sudo /etc/modprobe.d/blacklist.conf
Add following lines:

blacklist udlfb
blacklist udl


Than after you login manually load udl module:

sudo modprobe udl

After that

xrandr --listproviders

returns 2 providers:


Providers: number : 2
Provider 0: id: 0x54 cap: 0xf, Source Output, Sink Output, Source Offload, Sink Offload crtcs: 2 outputs: 3 associated providers: 1 name:ATI RV730 PRO [Radeon HD 4650] @ pci:0000:01:00.0
Provider 1: id: 0x4f2 cap: 0x2, Sink Output crtcs: 1 outputs: 1 associated providers: 1 name:modesetting


Now you can use arandr or xrandr to configure your displays.