[Bug 2081786] Re: Fix blank screen on external display after reconnecting the USB type-C

This bug is awaiting verification that the linux/6.8.0-50.51 kernel in
-proposed solves the problem. Please test the kernel and update this bug
with the results. If the problem is solved, change the tag
'verification-needed-noble-linux' to 'verification-done-noble-linux'. If
the problem still exists, change the tag 'verification-needed-noble-
linux' to 'verification-failed-noble-linux'.


If verification is not done by 5 working days from today, this fix will
be dropped from the source code, and this bug will be closed.


See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how
to enable and use -proposed. Thank you!


** Tags added: kernel-spammed-noble-linux-v2 verification-needed-noble-linux

--
You received this bug notification because you are subscribed to linux
in Ubuntu.
Matching subscriptions: Bgg, Bmail, Nb
https://bugs.launchpad.net/bugs/2081786

Title:
Fix blank screen on external display after reconnecting the USB type-C

Status in HWE Next:
New
Status in linux package in Ubuntu:
New
Status in linux source package in Noble:
Fix Committed

Bug description:
[SRU Justification]

[Impact]
The laptop of Intel RPL platform connects the external display via the HDMI/DisplayPort on a USB Type-C interfaced dock with dual type-C cable connected (WD19DC). The external display will stay blank after re-connect the docking station. It was observed on WD19DC with monitor 4K@60fps mode.

[Fix]
The upstream fix in kernel 6.11 594cf78dc36f ("drm/i915/dp_mst: Fix MST state after a sink reset") and its dependency are required.

[Test Case]
1. Connect the external monitor via the WD19DC docking station to the Intel powered laptop
2. Switch the monitor to 4K resolution and maximum refresh rate (>= 60fps)cul
3. Re-plug the WD19DC and check if the external display comes back in blank or normal.

[Where problems could occur]
Only observed on particular docking station and monitor. The risk should be low.

To manage notifications about this bug go to:
https://bugs.launchpad.net/hwe-next/+bug/2081786/+subscriptions