External Monitor not available after Suspend/Sleep

Dear all,

since many Nvidia driver versions (currently I am running 470.63), I am experiencing the issues that the external monitor (connected via DP-1-1.2 Thinkpad Thunderbolt 3 Workstation Dock Gen2 - latest Dock Firmware 3.1.70).
Connecting the external monitor directly to the notebook (either by USB-C or HDMI - without docking station), Suspend/Sleep works as expected.

The Dock itself is authorised and other devices connected or present via the dock are recognised after wake from sleep. Only external monitors are not recognized/available after wake from sleep.
System:
Lenovo Thinkpad P1 Gen2
Graphics: Nvidia Quadro T2000
OS: all versions up to Fedora 34
Docking: Thinkpad Thunderbolt 3 Workstation Dock Gen2 (I have it since summer spring 2020)

I had the hope, that this issue is somehow connected with the static noise issue (White noise/static with Quadro T2000 mobile and external monitor and will be fixed soon). So far it wasn’t.

What seems interesting is the fact that when removing the Nvidia driver and using the nouveau driver the external monitor (Thinkvision P27u) is available and activated after suspend/sleep.

But when running the Nvidia driver (no matter which version) the external monitor is not even recognized, so not available to the system. The only workaround the works so far is:

  1. wake from sleep
  2. disconnect external monitor from the thunderbolt dock (It does not matter if the monitor is disconnected before or after wake from sleep.)
  3. wait 5 to 10 seconds
  4. connect external monitor to the thunderbolt dock

Instead of disconnecting the external monitor it also works to disconnect and reconnect the whole dock while the monitor is connected to the dock.

This is only an issue when running the Nvidia driver.
Using the Nouveau driver sleep and wake from sleep works as expected.
Also in Windows sleep and wake from sleep with the dock works as it should.

Also in case the external monitor is directly connected to the Thinkpad P1 (either by USB-C or HDMI) (without docking station), Suspend/Sleep works as expected.

I generated the nvidia bug report 2 times:
Bug report after sleep, dock and external monitor still connected: after_sleep_nvidia-bug-report.log.gz (1.1 MB)

Bug report after sleep, external monitor disconnected and reconnected: disconnected-connected_nvidia-bug-report.log.gz (1.1 MB)

@amrits and NVIDIA_Team: Do you have any ideas? Is this a known issue?

Anyone else experiencing the same issue?