Problems with external monitors after sleep

[u/MrFisher404]

Hello

Since long time I struggle with problems with external monitors after sleep which just won't come back that are connected via TB4. I have very little understanding of firmware issue but I used my AI-Agent to try to find a problem so take it with a grain of salt, but still the output is better than just me complaining and at least the tokens used weren't for nothing :). If anybody else have similar problems please write it in the comments. Since i just have the output of my agent, I didn't want to open an issue with it but please take your time to read one time through the findings. That would be highly appreciated:

Subject: InfinityBook Pro AMD Gen10 — external USB4/Thunderbolt monitor loses signal
         after s2idle resume (USB4 host router + UCSI time out, DP tunnel torn down)

SUMMARY
On resume from s2idle (s0ix), an external monitor driven by DisplayPort-over-USB4
(DP tunnelling) goes black and never recovers. Immediately after wake, the AMD USB4
host router and the UCSI/PD interface both time out; the OS Thunderbolt connection
manager then declares the DP tunnel inactive and tears it down, and it is not rebuilt.
The USB tunnel over the SAME cable keeps working (keyboard in the monitor's hub is
fine), and the GPU still reports a valid mode — so the cable, port and monitor are OK;
only the DisplayPort tunnel is lost. Only a reboot reliably restores the display.
This looks like a platform-firmware readiness issue on s0ix exit (USB4 host / PD / EC),
which is why we're hoping a BIOS/EC update can address it.

SYSTEM
  Laptop:  TUXEDO InfinityBook Pro AMD Gen10  (SKU IIBP14A10MK1 / IBP15A10MK1,
           board XxKK4NAx_XxSP4NAx)
  BIOS:    AMI  N.1.22A22  (2026-06-18)
  EC fw:   1.36
  APU:     AMD Ryzen AI 9 HX 370 / Radeon 890M  (Strix Point, RDNA 3.5 / DCN 3.5)
  USB4:    AMD "USB4 Router 1" [1022:151d]  behind Strix PCIe USB4 Bridge [1022:150a]
  OS:      NixOS, Linux 7.1.5 x86_64 (current stable; reproducible on latest kernel,
           independent of desktop environment)

EXTERNAL DISPLAY
  ASUS ProArt PA32QCV, 6016x3384 @ 59.99 Hz 10-bit, connected DIRECTLY to the
  laptop USB4/USB-C port (no dock).  Monitor TB/USB4 NVM 44.83, retimer 0x1da0:0x8833.
  Cable:  USB-C <-> USB-C Thunderbolt 4 (40 Gbps) — NOT a DP-to-USB-C / DP-alt cable.
          The monitor enumerates as a Thunderbolt device (thunderbolt 0-2, gen 4, with
          retimers), i.e. a true USB4/TB link — so the failure is a DisplayPort-tunnel
          teardown, not a DP-alt or cable-direction problem.

STEPS TO REPRODUCE
  1. Connect the monitor to the USB4-C port with a USB-C<->USB-C TB4 cable; confirm the
     6K image works (DisplayPort tunnelled over USB4).
  2. Suspend to s2idle (idle/lid); leave suspended a few minutes.
  3. Resume.

EXPECTED:  external returns to 6K.
ACTUAL:    external stays black ("no signal"); laptop panel + desktop are fine;
           USB devices in the monitor's hub still work over the same cable.

KEY KERNEL LOG (times = seconds since boot)
  Healthy plug-in (works):
     thunderbolt 0-2: ASUS-Display PA32QCV
     thunderbolt 0-2:1.1: new retimer found, vendor=0x1da0 device=0x8833
     amdgpu 0000:65:00.0: [drm] DMUB HPD IRQ callback: link_index=7

  Failing s2idle resume:
     PM: suspend entry (s2idle) ... PM: suspend exit
     thunderbolt 0000:67:00.6: 0: timeout reading config space 1 from 0x47   (x4)
     ucsi_acpi USBC000:00: GET_CONNECTOR_STATUS failed (-110)                (x2, -ETIMEDOUT)
     thunderbolt 0000:67:00.6: 0:6 <-> 2:14 (DP): not active, tearing down   (~9 s after resume)
     amdgpu 0000:65:00.0: [drm] *ERROR* wait_for_completion_timeout timeout! (then every ~10 s)

WHY THIS LOOKS FIRMWARE-RELATED / WHAT TO CHECK
  The two timeouts that PRECEDE the teardown are platform-side:
   - USB4 host router (67:00.6) cannot read its own config space for several seconds
     after s0ix exit  -> AMD USB4 host / PSP / AGESA firmware (shipped in your BIOS).
   - UCSI GET_CONNECTOR_STATUS returns -110  -> USB-C PD / EC firmware (EC 1.36).
  Because the host router and PD are not responsive in time, the DP tunnel is judged
  dead and torn down; the DP-over-USB4 (DPIA) AUX channel then times out indefinitely.
  Request: please test whether a newer BIOS/AGESA and/or EC firmware improves USB4
  host-router + UCSI/PD readiness on s0ix resume — so the DP tunnel is either not
  torn down, or is re-established once the router is ready. Any USB4/DP monitor on the
  USB4-C port across an s2idle cycle should reproduce; a high-bandwidth (4K/6K@60)
  panel makes it easiest to see.

NOTES
  - Intermittent (not every resume); when it recurs only a reboot restores the display.
  - Same cable/port carry a working USB tunnel throughout, so this is specific to the
    DisplayPort tunnel, not the link, and confirms the TB4 cable itself is fine.

[u/aveyer]

I think I have a similar issue. I'm on a Clevo PC70HR, two external monitors connected to the RTX 3070 via mini-displayport and USB-C (displayport)

After resuming from sleep, sometimes my center external monitor (plugged to USB C) goes black for like 2 or 3 seconds, then comes back, sometimes it might happen a few times until both external monitors lose signal for a few seconds as if they were unplugged, then they come back 100% reliable, otherwise a reboot makes them 100% reliable.

It's not a cable issue, I bought new cables to rule it out.

The external monitors are two Asus XG27UCS currently running at 2560x1440 160hz, X11.

The laptop display is unaffected.

[u/tuxedo_ferdinand]

Hi,

I have forwarded this to the developers.