I have a laptop with a USB-C port, where I am trying to use a BENFEI USB-C to HDMI adapter in order to display something on an external monitor. However, even though my USB-C port definitely supports DP (it worked at an office a few months ago), it is no longer working for me.
The output of lsusb shows something called a "USB Type-C Digital AV Adapter":
Bus 004 Device 002: ID 0bda:0316 Realtek Semiconductor Corp. USB3.0-CRW
Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 003 Device 003: ID 343c:0000 xxxxxxxx USB Type-C Digital AV Adapter
Bus 003 Device 002: ID 04d9:a067 Holtek Semiconductor, Inc. USB Gaming Mouse
Bus 003 Device 006: ID 8087:0026 Intel Corp.
Bus 003 Device 005: ID 04f2:b71a Chicony Electronics Co., Ltd HD Webcam
Bus 003 Device 004: ID 048d:6004 Integrated Technology Express, Inc. ITE Device(8291)
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
And here is the output of xrandr:
Screen 0: minimum 8 x 8, current 2560 x 1440, maximum 32767 x 32767
DP-0 disconnected (normal left inverted right x axis y axis)
DP-1 disconnected (normal left inverted right x axis y axis)
DP-2 disconnected (normal left inverted right x axis y axis)
DP-3 disconnected (normal left inverted right x axis y axis)
HDMI-0 disconnected (normal left inverted right x axis y axis)
DP-4 connected primary 2560x1440+0+0 (normal left inverted right x axis y axis) 344mm x 194mm
2560x1440 40.00*+ 165.00
nvidia-smi returns NVIDIA-SMI 525.105.17 Driver Version: 525.105.17 CUDA Version: 12.0, and sudo prime-select query returns nvidia, though changing that to intel doesn't make a difference.
journalctl displays the following when the adapter is plugged in:
Jun 20 11:08:45 morin-y kernel: usb 3-5: new low-speed USB device number 7 using xhci_hcd
Jun 20 11:08:46 morin-y kernel: usb 3-5: No LPM exit latency info found, disabling LPM.
Jun 20 11:08:46 morin-y kernel: usb 3-5: New USB device found, idVendor=343c, idProduct=0000, bcdDevice= 0.00
Jun 20 11:08:46 morin-y kernel: usb 3-5: New USB device strings: Mfr=1, Product=2, SerialNumber=3
Jun 20 11:08:46 morin-y kernel: usb 3-5: Product: USB Type-C Digital AV Adapter
Jun 20 11:08:46 morin-y kernel: usb 3-5: Manufacturer: xxxxxxxx
Jun 20 11:08:46 morin-y kernel: usb 3-5: SerialNumber: 000000000000
I attempted editing nvidia-kms.conf as mentioned here, with no success. Is there anything else I can try?
