Monitor Not Detected when Connected to Belkin Docking Station via DisplayPort on Ubuntu

[Vinoth]

Dear Ubuntu Bug Tracking Team,

I hope this message finds you well. I am writing to report an issue I have encountered while using Ubuntu.

Issue Description:
When connecting my BenQ monitor to a Belkin docking station via DisplayPort, Ubuntu fails to detect the monitor. Other monitor connected to same docking station via hdmi is working

Thank you for your attention to this matter.

ProblemType: Bug
DistroRelease: Ubuntu 22.04
Package: xorg 1:7.7+23ubuntu2
ProcVersionSignature: Ubuntu 6.5.0-17.17~22.04.1-generic 6.5.8
Uname: Linux 6.5.0-17-generic x86_64
ApportVersion: 2.20.11-0ubuntu82.5
Architecture: amd64
BootLog: Error: [Errno 13] Permission denied: '/var/log/boot.log'
CasperMD5CheckResult: unknown
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: None
CurrentDesktop: ubuntu:GNOME
Date: Sat Feb 17 12:33:13 2024
DistUpgraded: 2022-09-23 16:50:19,545 DEBUG Running PostInstallScript: '/usr/lib/ubuntu-advantage/upgrade_lts_contract.py'
DistroCodename: jammy
DistroVariant: ubuntu
DkmsStatus: nct6687d/20240204-100005, 6.5.0-17-generic, x86_64: installed
ExtraDebuggingInterest: I just need to know a workaround
GraphicsCard:
 Intel Corporation CometLake-U GT2 [UHD Graphics] [8086:9b41] (rev 02) (prog-if 00 [VGA controller])
   Subsystem: Lenovo CometLake-U GT2 [UHD Graphics] [17aa:22ac]
InstallationDate: Installed on 2020-06-01 (1355 days ago)
InstallationMedia: Ubuntu 20.04 LTS "Focal Fossa" - Release amd64 (20200423)
MachineType: LENOVO 20SDCTO1WW
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-6.5.0-17-generic root=UUID=b6e3b307-fcfb-4b70-ba21-5b72784f279c ro quiet splash vt.handoff=7
SourcePackage: xorg
UpgradeStatus: Upgraded to jammy on 2022-09-23 (511 days ago)
dmi.bios.date: 07/17/2023
dmi.bios.release: 1.25
dmi.bios.vendor: LENOVO
dmi.bios.version: N2SET31W (1.25 )
dmi.board.asset.tag: Not Available
dmi.board.name: 20SDCTO1WW
dmi.board.vendor: LENOVO
dmi.board.version: SDK0J40709 WIN
dmi.chassis.asset.tag: No Asset Information
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: None
dmi.ec.firmware.release: 1.6
dmi.modalias: dmi:bvnLENOVO:bvrN2SET31W(1.25):bd07/17/2023:br1.25:efr1.6:svnLENOVO:pn20SDCTO1WW:pvrThinkPadX390:rvnLENOVO:rn20SDCTO1WW:rvrSDK0J40709WIN:cvnLENOVO:ct10:cvrNone:skuLENOVO_MT_20SD_BU_Think_FM_ThinkPadX390:
dmi.product.family: ThinkPad X390
dmi.product.name: 20SDCTO1WW
dmi.product.sku: LENOVO_MT_20SD_BU_Think_FM_ThinkPad X390
dmi.product.version: ThinkPad X390
dmi.sys.vendor: LENOVO
version.compiz: compiz N/A
version.libdrm2: libdrm2 2.4.113-2~ubuntu0.22.04.1
version.libgl1-mesa-dri: libgl1-mesa-dri 23.2.1-1ubuntu3.1~22.04.2
version.libgl1-mesa-glx: libgl1-mesa-glx 23.0.4-0ubuntu1~22.04.1
version.xserver-xorg-core: xserver-xorg-core 2:21.1.4-2ubuntu1.7~22.04.8
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:19.1.0-2ubuntu1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20210115-1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.17-2build1

[Daniel van Vugt (vanvugt)]

I wonder if the Belkin docking station has enough bandwidth to drive multiple monitors simultaneously. Have you tried unplugging everything from the dock and just plugging in a monitor to the DisplayPort alone?

Also next time the bug occurs, please run:

  journalctl -b0 > journal.txt

and attach the resulting text file here.

[Daniel van Vugt (vanvugt)]

Also the specs for the Lenovo X390 suggest only one of the USB-C ports supports Thunderbolt, so it might be worth checking to see the dock is plugged into that port for the best performance.

[Launchpad Janitor (janitor)]

[Expired for linux-hwe-6.5 (Ubuntu) because there has been no activity for 60 days.]