USB 2.0 UGA Display UBUNTU 20.10

[Anderson Costa]

Goodnight. I am inexperienced for installations at UBUNTU.

I have on my notebook the Ububtu 20.10 + a Monitor via HDMI and I was able to install the Displaylink driver to use another monitor, Ubuntu recognizes the USB Display Adapter, however the 3rd monitor does not appear in the settings.

I've done several tests without success. can anybody help me?

Boa noite. Sou inexperiente para intalações no UBUNTU.

Tenho no meu notebook o Ububtu 20.10 + um Monitor via HDMI e consegui instalar o driver do Displaylink para usar mais um monitor, o Ubuntu reconhece o USB Display Adapter, porém não aparece o 3º monitor nas configurações.

Já fiz vários testes sem sucesso. Alguém poderia me ajudar?

[CangHousehold]

Hello there.

I spent 4 hours yesterday and today researching solutions for using DisplayLink (Pluggable man.) UGA-165 as a VGA output alongside an onboard HDMI output for my Raspberry Pi 4. It turns out, DL-165 Chipset is natively supported (given the pivotal udl package is pre-installed) by my Pi and can work flawlessly to extend the onboard HDMI output.

First of all, I can tell you the experience is tough. It wasn't plug-n-play, and I expected this. It was more like research, code, research, code, reboot, code, research, and finally get it to work. You may say the Raspberry Pi 4 is not applicable to your instance, but given they are both Debian derivatives and even use the same default windows server and manager. My setup should be relevant to you.

Since your post's title is USB2.0 UGA display, I am assuming it has DL-1x5 chipset.

Before you start, make sure you have the SSH on your Ubuntu enabled. In case the setup went awry and the displays are all blank, you can still interact with your machine, including using sudo.

1) probe the existence of udl package.

lsmod | grep "udl"

This package should come with the Linux kernel. You need to install it if you don't have this package.
2) locate X11 configuration and create xorg.conf if necessary. For Pi, I found it in /etc/X11, Ubuntu should be the same. xorg.conf file may not exist in this folder. Mine did not exist. So I created this file in the /etc/X11 directory. During a normal boot-up, the system will search for displays and apply default drivers for them. Certainly the DisplayLink driver is not a norm. By having a xorg.conf, I believe it would override the automatic mechanism and render the GUI Display settings to be useless. So, avoid using GUI Display settings after configuring xorg.conf. You can change any settings in xorg.conf.

I used vi to edit the settings. You can use nano or vim. I would suggest a command line-ready text editor in case you need to change this setting through SSH if the screens all have failed.

cd /etc/X11 # locate X11 configuration, this is only a part of the configuration
# root privilege required
sudo vi xorg.conf

You may need to type in the following with modifications. Be careful, if you feel uncertain, always check the xorg manual before proceeding.

# how screens are arranged
Section "ServerLayout"
        Identifier "MyServerLayout" # name customizable
        Screen 0 "BuiltInScr" 0 0 # define origin, main screen, name customizable
        Screen 1 "HDMIScr" RightOf "BuiltInScr" # define HDMI output, right of laptop screen. Allowed positioning values are LeftOf, RightOf, Above, and Below. You can use coordinates system too for more flexibility. Please see manual for this setup.
        Screen 2 "DisplayLinkScr" RightOf "HDMISrc"
        Option "Xinerama" "true" # important, allow window system to use multiple screens as one large display
EndSection

Section "Files"
        ModulePath "/usr/lib/xorg/modules" # you may need to look around to find your fbdev and fbturbo drivers. This is a hard part.
        # add other ModulePath if drivers are stored at more than one places.
EndSection

Section "Device"
        Identifier "BuiltInDev" # name customizable
        Driver "fbturbo"
        Option "fbdev" "/dev/fb0" # locate your devices. Since you have three displays, in /dev folder, there should be fb0, fb1, fb2. You need to run dmesg, or check the Xorg.0.log in /var/log/xorg to correspond each fb* to all three screens. Another hard part.
EndSection

Section "Device"
        Identifier "HDMIDev" # name customizable
        Driver "fbturbo"
        Option "fbdev" "/dev/fb1"
EndSection

Section "Device"
        Identifier "DisplayLinkDev" # name customizable
        Driver "fbturbo"
        Option "fbdev" "/dev/fb2"
EndSection

Section "Monitor"
        Identifier "BuiltInMon"
EndSection

Section "Monitor"
        Identifier "HDMIMon"
EndSection

Section "Monitor"
        Identifier "DisplayLinkMon"
EndSection

Section "Screen"
        Identifier "BuiltInSrc"
        Device "BuiltInDev"
        Monitor "BuiltInMon"
        # subsection probably unnecessary for the built-in screen
        SubSection "Display"
                Modes "1920x1080"
        EndSubSection
EndSection

Section "Screen"
        Identifier "HDMISrc"
        Device "HDMIDev"
        Monitor "HDMIMon"
        SubSection "Display"
                Modes "1920x1080" # your HDMI monitor resolution, probably unnecessary too.
        EndSubSection
EndSection

Section "Screen"
        Identifier "DisplayLinkScr"
        Device "DisplayLinkDev"
        Monitor "DisplayLinkMon"
        SubSection "Display"
                Depth 16 # highest is 16 I believe
                Modes "1440x900" # your DL monitor resolution, probably 1920x1080. I have an old VGA monitor.
        EndSubSection
EndSection

After finishing typing these, :wq in vi. Then reboot the machine.

I tried to restart the window manager service, and it reloads the screen configuration without rebooting.

sudo service lightdm restart

I hope you have success in configuring the screens. I do have another UGA-165 in the closet. I am going to try two simultaneous DL devices in the future. My Pi has two built-in 4K HDMI, so plenty of screens already. I may consider building a monitor wall. I checked htop when running both an onboard HDMI and the DL dongle. The CPU consumption on my Pi is 2.2% 0% 0% 0% (4 core). So using the DL should not drag your machine's performance down. Your computer must have a better CPU than the BCM2711 in the Pi.

Sorry for this wall of text. This may be a documentation for others and myself, in case I need to tweak some settings or add more screens.