Bug 2029965

Summary:	MST Docking station, how to configure, who talks to the Billboard device?
Product:	[Fedora] Fedora	Reporter:	GroovieMan <christian.groove>
Component:	gnome-monitor-config	Assignee:	Jeremy Newton <alexjnewt>
Status:	CLOSED NOTABUG	QA Contact:	Fedora Extras Quality Assurance <extras-qa>
Severity:	high	Docs Contact:
Priority:	unspecified
Version:	35	CC:	alexjnewt
Target Milestone:	---
Target Release:	---
Hardware:	x86_64
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	---
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2022-01-02 10:47:00 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description GroovieMan 2021-12-07 16:57:28 UTC

Description of problem:
i am using ThinkBook P16 with 2 USB-C (with Alt-DP 1.4 Support). A connected MST docking station fails to display the monitors, because (thats what i think) nobody talks to the Billboard device, that can be accessed via USB (see ID 2109:8888). The device uses the correct classId=0x11, so the gnome monitor config tools shall be capable to enable it, but it does not!

$ lsusb
Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 003 Device 003: ID 048d:c916 Integrated Technology Express, Inc. ITE Device(8296)
.....
Bus 001 Device 004: ID 04f3:0c4b Elan Microelectronics Corp. ELAN:Fingerprint
Bus 001 Device 003: ID 8087:0029 Intel Corp. AX200 Bluetooth
Bus 001 Device 007: ID 2109:8888 VIA Labs, Inc. USB Billboard Device
Bus 001 Device 009: ID 046d:0825 Logitech, Inc. Webcam C270
Bus 001 Device 011: ID 0557:2407 ATEN International Co., Ltd USB 2.0 Peripheral Switch
...
I would assume, that the configuration-center does parse the usb-tree and configure the attached external monitors talking to the Billboad Service.

Version-Release number of selected component (if applicable):
gnome-control-center-41.1-1.fc35

How reproducible:
Nothing to reproduce, it simply does not work.

Steps to Reproduce:
1. start config center and there is no way to enable the external monitors
2.
3.

Actual results:
The external monitors can not be accessed.

Expected results:
A tool, that allows me to configure external displays via a docking station, because der driver supports DP-Alt.

Additional info:

Comment 1 GroovieMan 2021-12-07 21:02:22 UTC

I placed a question in gnomes-gitlab:
https://gitlab.gnome.org/GNOME/mutter/-/issues/1391

Comment 2 GroovieMan 2021-12-19 11:53:14 UTC

Yesterday i found out, that the MST-dock attached monitors are beeing noticed by the kernel/udev.
The question is, why the control-center or maybe mutter is not able to offer the for configuration
in the video settings menu? (see issue Bug 2028365)


1) Check out available monitors via CLI, because there is no running desktop here:

[cgroove@foreman ~]$ ls -l /sys/class/drm
insgesamt 0
lrwxrwxrwx. 1 root root    0 18. Dez 2021  card0 -> ../../devices/pci0000:00/0000:00:01.1/0000:01:00.0/drm/card0
lrwxrwxrwx. 1 root root    0 18. Dez 2021  card0-DP-1 -> ../../devices/pci0000:00/0000:00:01.1/0000:01:00.0/drm/card0/card0-DP-1
lrwxrwxrwx. 1 root root    0 18. Dez 2021  card0-DP-2 -> ../../devices/pci0000:00/0000:00:01.1/0000:01:00.0/drm/card0/card0-DP-2
lrwxrwxrwx. 1 root root    0 18. Dez 2021  card0-DP-3 -> ../../devices/pci0000:00/0000:00:01.1/0000:01:00.0/drm/card0/card0-DP-3
lrwxrwxrwx. 1 root root    0 18. Dez 2021  card0-DP-6 -> ../../devices/pci0000:00/0000:00:01.1/0000:01:00.0/drm/card0/card0-DP-6
lrwxrwxrwx. 1 root root    0 18. Dez 2021  card0-DP-7 -> ../../devices/pci0000:00/0000:00:01.1/0000:01:00.0/drm/card0/card0-DP-7
lrwxrwxrwx. 1 root root    0 18. Dez 2021  card0-eDP-1 -> ../../devices/pci0000:00/0000:00:01.1/0000:01:00.0/drm/card0/card0-eDP-1
lrwxrwxrwx. 1 root root    0 18. Dez 2021  card1 -> ../../devices/pci0000:00/0000:00:08.1/0000:06:00.0/drm/card1
lrwxrwxrwx. 1 root root    0 18. Dez 2021  card1-DP-4 -> ../../devices/pci0000:00/0000:00:08.1/0000:06:00.0/drm/card1/card1-DP-4
lrwxrwxrwx. 1 root root    0 18. Dez 2021  card1-DP-5 -> ../../devices/pci0000:00/0000:00:08.1/0000:06:00.0/drm/card1/card1-DP-5
lrwxrwxrwx. 1 root root    0 18. Dez 2021  card1-eDP-2 -> ../../devices/pci0000:00/0000:00:08.1/0000:06:00.0/drm/card1/card1-eDP-2
lrwxrwxrwx. 1 root root    0 18. Dez 2021  renderD128 -> ../../devices/pci0000:00/0000:00:01.1/0000:01:00.0/drm/renderD128
lrwxrwxrwx. 1 root root    0 18. Dez 2021  renderD129 -> ../../devices/pci0000:00/0000:00:08.1/0000:06:00.0/drm/renderD129

and let's check out, what is behind card0-DP-7 (yepp this is one attached monitor)
[cgroove@foreman ~]$ cat /sys/class/drm/card0-DP-7/modes 
3840x2160
3840x2160
2560x1440
1920x1080
1920x1080
1920x1080
1600x900
1280x1024
1280x800
1280x720
1280x720
1280x720
1024x768
800x600
720x480
720x480
640x480
640x480
640x480

Comment 3 GroovieMan 2022-01-02 10:48:15 UTC

This bug is a nuveau issue. There is another one around controld-center with the nvidia bug