DisplayLink screen detected but fails to activate on Pop!_OS 22.04 with NVIDIA - (EE) modeset(G0): failed to set mode: Input/output error

System Information
Distribution: Pop!_OS 22.04 LTS
Graphics Card: NVIDIA RTX 4070 TI
Graphics Mode: NVIDIA Graphics (not hybrid or integrated)
DisplayLink Device: 10" Mimo UM-1080C-G 1280x800 (Note: This is a touchscreen display tablet, not a standard monitor).
Kernel Version: 6.12.10-76061203-generic
Display Server: X11 (echo $XDG_SESSION_TYPE returns x11)
displaylink-debian script: Latest version, installed on June 5th, 2025.

Problem Description

The display output of my DisplayLink-based touchscreen tablet fails to activate after the initial boot stage. The device is correctly detected by the system, and its touch input is registered, but the screen remains black. The system's display settings panel is unable to apply "Extend" or "Mirror" modes for the display.
The failure of the video output prevents any further configuration, such as mapping the touch input to the correct screen.

Key Symptoms & Boot Sequence Behavior

During system boot, at the disk decryption prompt (LUKS), the display is correctly mirrored to both the main monitor and the DisplayLink tablet. Both screens are active even when connected only via USB.
After successfully entering the decryption password, the DisplayLink tablet's screen goes black and stays black.
By the time the GDM login screen (user selection) appears, only the primary monitor is active.
The displaylink-driver.service is active (running).
The evdi kernel module is loaded.
xrandr correctly lists the DisplayLink tablet's display (as VGA-1-1) and shows its status as connected.

Troubleshooting Steps Taken

Verified the displaylink-driver.service is active and running.
Verified the evdi module is loaded via lsmod.
Confirmed the user session is x11, not wayland.
Created a 20-displaylink.conf file using an OutputClass section to explicitly assign a driver to the evdi device.
Tested with both Driver "modesetting" and Driver "displaylink" in the xorg.conf file. The system boots, but the screen still fails to activate.
Manual activation via xrandr --output VGA-1-1 --auto also fails without any error message in the terminal.

Key Log Output from journalctl

The journalctl log shows that everything seems to work correctly up until the final modesetting attempt. The OutputClass from our config is correctly applied, but then a critical error occurs.

Critical Error:
(EE) modeset(G0): failed to set mode: Input/output error

This error appears multiple times in the log.

Evidence that the device and configuration are being read correctly:
$ journalctl -b | grep "VGA-1-1"

(II) modeset(G0): Output VGA-1-1 has no monitor section
(II) modeset(G0): EDID for output VGA-1-1
(II) modeset(G0): Printing probed modes for output VGA-1-1

$ journalctl -b | grep -i "evdi\|displaylink"

...
(II) Applying OutputClass "DisplayLink" options to /dev/dri/card2
(II) Applying OutputClass "DisplayLink" options to /dev/dri/card3
...

The fact that the display works during the initial decryption phase (which uses a simple framebuffer driver) but fails as soon as the full graphics stack (with the NVIDIA driver) is loaded strongly suggests a driver conflict. It seems there is a fundamental incompatibility between the proprietary NVIDIA driver, the Xorg server on Pop!_OS, and the way the DisplayLink driver tries to initialize the screen. The "Input/output error" during modesetting seems to be the core of the problem.

Any help or insight would be greatly appreciated. Thank you.

Start by reproducing the transition from the working LUKS framebuffer stage to the X11/GDM session, then inspect the repeated modeset(G0) error alongside xrandr --output VGA-1-1 --auto. Done would require establishing the compatibility cause and documenting a confirmed resolution or limitation for Pop!_OS 22.04, NVIDIA RTX 4070 Ti, and the Mimo UM-1080C-G.

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