PROBLEM: Laptop kills USB-C hubs

[Alex Deucher]

On Thu, Oct 21, 2021 at 6:55 PM Gabriel <git at gabscap.de> wrote:
>
> [1.] One line summary of the problem:
>
> Laptop kills USB-C hubs.
>
>
> [2.] Full description of the problem/report:
>
> I own a ThinkPad T14s (AMD) and used a USB-C Hub [a] without any
> problems for half a year. Then, I bought a new ThinkPad E15 Gen3 (AMD)
> and used it with my USB-C hub, which worked fine at the beginning. After
> a few days, the USB-C hub stopped working. I thought nothing of it and
> ordered a new one [b].
> The new one worked fine for 1-2 days, until the HDMI ports stopped
> working while being connected to the new laptop. USB/Ethernet ports
> continued to work.
> I ordered the USB-C hub [b] again. Same story, except it died
> completely. All ports stopped working.
>
> I noticed a kernel warning [6.], which is the same for all three USB-C
> hub deaths. This only happened after the system woke up from susped mode.
>
> I dont't know if this is a hardware or kernel issue. Unfortunately I
> can't debug this any further, because I don't have any excess USB-C hubs
> to brick.

There was a recent regression in the driver related to USB-C DP
alt-mode not working after resume from suspend in some cases.  You can
find more details and the fix on this bug:
https://gitlab.freedesktop.org/drm/amd/-/issues/1735
I haven't heard of any damage to hardware however.

Alex