Bug 2303709 - Monitors not recognized correctly through CalDigit TS4 dock on AMD 7840U
Summary: Monitors not recognized correctly through CalDigit TS4 dock on AMD 7840U
Keywords:
Status: CLOSED EOL
Alias: None
Product: Fedora
Classification: Fedora
Component: wayland
Version: 40
Hardware: x86_64
OS: Linux
unspecified
medium
Target Milestone: ---
Assignee: Adam Jackson
QA Contact: Fedora Extras Quality Assurance
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2024-08-08 15:46 UTC by keawade
Modified: 2025-05-30 21:17 UTC (History)
7 users (show)

Fixed In Version:
Clone Of:
Environment:
Last Closed: 2025-05-20 19:23:25 UTC
Type: ---
Embargoed:


Attachments (Terms of Use)

Description keawade 2024-08-08 15:46:46 UTC
On a Framework laptop with the AMD 7840U mainboard:

Under wayland external displays connect but aren’t correctly identified and are instead listed as “Unknown display” with the only available resolution being 640x480.

Xorg behaves the same way. However I was able to implement a janky workaround by manually configuring Xorg display modes for the monitors.

# Use cvt to get the modeline
cvt 2560 1440
# Use the modeline to create a new mode
xrandr --newmode "2560x1440_60.00"  312.25  2560 2752 3024 3488  1440 1443 1448 1493 -hsync +vsync
# Add the new mode to the displays
xrandr --addmode DisplayPort-4 "2560x1440_60.00"
xrandr --addmode DisplayPort-5 "2560x1440_60.00"
# Use the new modes on the displays
xrandr --output DisplayPort-4 --mode "2560x1440_60.00"
xrandr --output DisplayPort-5 --mode "2560x1440_60.00"

This got the monitors working temporarily but unplugging the dock and plugging it back in results in the monitors going back to a default 640x480. At this point I don’t have to add the display modes again but I do have to open the Display Settings panel and set their resolution and positions correctly which is a huge hassle.

If I plug the monitors into the laptop directly via DisplayPort expansion cards they are immediately correctly recognized without issue.

More info and users reporting similar behavior can be found in the Framework forum thread here: https://community.frame.work/t/responded-amd-mainboard-caldigit-ts4-dock-monitors-not-identified/39228

Reproducible: Always

Steps to Reproduce:
1. Connect external monitor(s) to a CalDigit TS4 dock
2. Connect CalDigit TS4 dock to Framework laptop with an AMD 7840U mainboard
Actual Results:  
Monitors are recognized and display signal is sent but the monitors are not properly identified and instead are identified as "Unknown display" and only sent 640x480 display signal.

Expected Results:  
Monitors should be correctly identified and able to select supported display modes.

Comment 1 Olivier Fourdan 2024-08-08 17:11:04 UTC
Wayland is just a protocol specification in XML and the low-level C library that deals with the protocol.

This issue here is a bug not with the protocol itself but with either the kernel driver, your compositor or desktop environment's implementation of the Wayland protocol and surrounding functionality.

But definitely to Wayland.

Comment 2 Olivier Fourdan 2024-08-08 17:18:36 UTC
(In reply to Olivier Fourdan from comment #1)
> But definitely to Wayland.

Typo there, I mean, definitely _not_ Wayland.

Comment 3 keawade 2024-08-08 17:39:58 UTC
Okay that makes sense. Sorry I'm not entirely sure what specific component to list it under. For example there are many kernel components available in the components list but I don't know what the majority of them are to be able to categorize it myself. Are you able to recommend a specific component or is that something that is done as part of normal triage?

Comment 4 Daniel Power 2024-08-08 19:20:41 UTC
I'm affected by this issue as well. It occurs on both Wayland and Xorg, so I don't believe it's a bug with Wayland.

I am also using a Caldigit TS4 with an Amd 7840U Framework laptop. In my testing of two monitors, the bug only occurs with one of them. Both monitors work fine in the same configuration but with a Macbook, so I am confident the monitor is not defective.

I found this upstream bug report which appears to be relevant: https://gitlab.freedesktop.org/drm/amd/-/issues/3050

Comment 5 zeddiexx 2024-08-10 19:49:59 UTC
Just to add, this is also happening with other docking stations.  I can confirm this is also happening with a Dell Thunderbolt Laptop Computer Dock - WD22TB4 and someone also mentioned it is happening with a UGREEN Revodok Max 313.

To note, I can confirm both the Dell WD22TB4 and the CalDigit TS4 behaves correctly in Windows 11 with my Framework Laptop 16 AMD Ryzen 7 7840HS.

https://community.frame.work/t/responded-amd-mainboard-caldigit-ts4-dock-monitors-not-identified
https://community.frame.work/t/guide-ugreen-revodok-max-313
https://community.frame.work/t/usb-c-thunderbolt-dock-megathread/1460/492

Comment 6 Aoife Moloney 2025-04-28 13:37:30 UTC
This message is a reminder that Fedora Linux 40 is nearing its end of life.
Fedora will stop maintaining and issuing updates for Fedora Linux 40 on 2025-05-13.
It is Fedora's policy to close all bug reports from releases that are no longer
maintained. At that time this bug will be closed as EOL if it remains open with a
'version' of '40'.

Package Maintainer: If you wish for this bug to remain open because you
plan to fix it in a currently maintained version, change the 'version' 
to a later Fedora Linux version. Note that the version field may be hidden.
Click the "Show advanced fields" button if you do not see it.

Thank you for reporting this issue and we are sorry that we were not 
able to fix it before Fedora Linux 40 is end of life. If you would still like 
to see this bug fixed and are able to reproduce it against a later version 
of Fedora Linux, you are encouraged to change the 'version' to a later version
prior to this bug being closed.

Comment 7 zeddiexx 2025-04-28 18:45:20 UTC
Logged in just to see if I have the ability to change the version number, but when I did, I didn't see a version field to change.

Comment 8 zeddiexx 2025-04-28 18:47:19 UTC
Oh, I see the field now - had to click on Show advanced fields button.  However, it doesn't look like I can change the version #.  Maybe the original poster (keawade) does.

Comment 9 Aoife Moloney 2025-05-20 19:23:25 UTC
Fedora Linux 40 entered end-of-life (EOL) status on 2025-05-13.

Fedora Linux 40 is no longer maintained, which means that it
will not receive any further security or bug fix updates. As a result we
are closing this bug.

If you can reproduce this bug against a currently maintained version of Fedora Linux
please feel free to reopen this bug against that version. Note that the version
field may be hidden. Click the "Show advanced fields" button if you do not see
the version field.

If you are unable to reopen this bug, please file a new report against an
active release.

Thank you for reporting this bug and we are sorry it could not be fixed.

Comment 10 jack 2025-05-30 21:17:09 UTC
I had a similar issue on my AMD Framework, and this seems to be fixed in kernel 6.14.8-300.fc42. Hooray!


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