Monitor does not get a signal via USB-C (DP)

chhe · April 5, 2021, 4:58pm

Hello all

I have a Medion notebook E4253 and a Dell monitor U2720Q. The notebook has a USB-C with DisplayPort port and I would like to use the Dell monitor with it. But unfortunately I get no signal when I connect the USB-C cable that comes with the monitor. The monitor also has an integrated HUB, which is recognized by the operating system without a problem as soon as I connect the notebook with the USB-C cable.

lspci | grep VGA
VGA compatible controller: Intel Corporation GeminiLake [UHD Graphics 605] (rev 03)

lscpu | grep -E ‘(odel|amily)’
Intel(R) Pentium(R) Silver N5000 CPU @ 1.10GHz

lsusb without connected USB-C cabel
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 004: ID 8087:0aaa Intel Corp. Bluetooth 9460/9560 Jefferson Peak (JfP)
Bus 001 Device 003: ID 058f:3822 Alcor Micro Corp. USB 2.0 Camera
Bus 001 Device 002: ID 0bda:0129 Realtek Semiconductor Corp. RTS5129 Card Reader Controller
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

lsusb with connected USB-C cabel
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 004: ID 8087:0aaa Intel Corp. Bluetooth 9460/9560 Jefferson Peak (JfP)
Bus 001 Device 003: ID 058f:3822 Alcor Micro Corp. USB 2.0 Camera
Bus 001 Device 002: ID 0bda:0129 Realtek Semiconductor Corp. RTS5129 Card Reader Controller
Bus 001 Device 016: ID 0451:82ff Texas Instruments, Inc.
Bus 001 Device 015: ID 0451:8442 Texas Instruments, Inc.
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

The window manager is wayland.

Currently, after much google, I unfortunately do not know what to do and I could not fix the problem. I would rule out a defect in the cable and monitor, since I still have a MacBook and here everything works plug & play.

I am very grateful for your help
Many greetings

nickavem · April 5, 2021, 5:25pm

The window manager is wayland.

Does it work on X?

chhe · April 5, 2021, 7:06pm

Unfortunately no. Changing the window manager to X was the first thing I tried.

tjdoyle · April 5, 2021, 8:51pm

Hi,

With the USB-C cable connected, whats the output of usb-devices ?

Thanks Tom.

sampsonf · April 6, 2021, 4:24am

Can you try, at the Monitor end, disable auto detect of input source by manually setting input to usb-c port?

Sometimes when both ends are auto detecting, the end result is not the best.

chhe · April 6, 2021, 10:36am

@tjdoyle here is the output:
T: Bus=01 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#= 1 Spd=480 MxCh= 9
D: Ver= 2.00 Cls=09(hub ) Sub=00 Prot=01 MxPS=64 #Cfgs= 1
P: Vendor=1d6b ProdID=0002 Rev=05.11
S: Manufacturer=Linux 5.11.10-200.fc33.x86_64 xhci-hcd
S: Product=xHCI Host Controller
S: SerialNumber=0000:00:15.0
C: #Ifs= 1 Cfg#= 1 Atr=e0 MxPwr=0mA
I: If#=0x0 Alt= 0 #EPs= 1 Cls=09(hub ) Sub=00 Prot=00 Driver=hub

T: Bus=01 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#= 21 Spd=480 MxCh= 6
D: Ver= 2.10 Cls=09(hub ) Sub=00 Prot=02 MxPS=64 #Cfgs= 1
P: Vendor=0451 ProdID=8442 Rev=01.00
S: SerialNumber=B701008983CB
C: #Ifs= 1 Cfg#= 1 Atr=e0 MxPwr=0mA
I: If#=0x0 Alt= 1 #EPs= 1 Cls=09(hub ) Sub=00 Prot=02 Driver=hub

T: Bus=01 Lev=02 Prnt=21 Port=04 Cnt=01 Dev#= 22 Spd=480 MxCh= 0
D: Ver= 2.01 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs= 1
P: Vendor=0451 ProdID=82ff Rev=02.00
C: #Ifs= 1 Cfg#= 1 Atr=c0 MxPwr=0mA
I: If#=0x0 Alt= 0 #EPs= 1 Cls=03(HID ) Sub=00 Prot=00 Driver=usbhid

T: Bus=01 Lev=01 Prnt=01 Port=02 Cnt=02 Dev#= 2 Spd=480 MxCh= 0
D: Ver= 2.00 Cls=ff(vend.) Sub=ff Prot=ff MxPS=64 #Cfgs= 1
P: Vendor=0bda ProdID=0129 Rev=39.60
S: Manufacturer=Generic
S: Product=USB2.0-CRW
S: SerialNumber=20100201396000000
C: #Ifs= 1 Cfg#= 1 Atr=a0 MxPwr=500mA
I: If#=0x0 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=06 Prot=50 Driver=rtsx_usb

T: Bus=01 Lev=01 Prnt=01 Port=05 Cnt=03 Dev#= 3 Spd=480 MxCh= 0
D: Ver= 2.00 Cls=ef(misc ) Sub=02 Prot=01 MxPS=64 #Cfgs= 1
P: Vendor=058f ProdID=3822 Rev=06.00
S: Product=USB 2.0 Camera
C: #Ifs= 2 Cfg#= 1 Atr=80 MxPwr=200mA
I: If#=0x0 Alt= 0 #EPs= 1 Cls=0e(video) Sub=01 Prot=00 Driver=uvcvideo
I: If#=0x1 Alt= 0 #EPs= 0 Cls=0e(video) Sub=02 Prot=00 Driver=uvcvideo

T: Bus=01 Lev=01 Prnt=01 Port=08 Cnt=04 Dev#= 4 Spd=12 MxCh= 0
D: Ver= 2.00 Cls=e0(wlcon) Sub=01 Prot=01 MxPS=64 #Cfgs= 1
P: Vendor=8087 ProdID=0aaa Rev=00.02
C: #Ifs= 2 Cfg#= 1 Atr=e0 MxPwr=100mA
I: If#=0x0 Alt= 0 #EPs= 3 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
I: If#=0x1 Alt= 0 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb

T: Bus=02 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#= 1 Spd=5000 MxCh= 7
D: Ver= 3.00 Cls=09(hub ) Sub=00 Prot=03 MxPS= 9 #Cfgs= 1
P: Vendor=1d6b ProdID=0003 Rev=05.11
S: Manufacturer=Linux 5.11.10-200.fc33.x86_64 xhci-hcd
S: Product=xHCI Host Controller
S: SerialNumber=0000:00:15.0
C: #Ifs= 1 Cfg#= 1 Atr=e0 MxPwr=0mA
I: If#=0x0 Alt= 0 #EPs= 1 Cls=09(hub ) Sub=00 Prot=00 Driver=hub

@SampsonF I have turned off auto detect, but without success

sampsonf · April 6, 2021, 2:24pm

If you have a type-C to display port adapter on hand to test with, it should help further to isolate if it is a hardware of software issue.

Sometimes system Firmware are controlling the functions of multi-function ports. Please do check the System Firmware settings and if firmware updates are available or not.

tjdoyle · April 6, 2021, 5:14pm

Hi,

Doesn’t look like the display is being detected, only reporting the hub & and an input device. Maybe easier to use via the display port.

Thanks Tom.

chhe · April 18, 2021, 9:44am

@tjdoyle @SampsonF

A little update on this issue:
I have now ordered a USB-C to DisplayPort cable. After trying it out, I have now unfortunately encountered another problem.

if I plug in the cable while the computer is running, both screens go black. If I unplug the cable again, then the screen of the notebook remains black and I have to restart the notebook via the power button to geht ist back working.
If the cable is plugged in during the boot process, everything works fine - only the integrated hub is not recognized. But, I don’t care about that for now.

One more thing: I read again in the specifications of the notebook. It says that a second display via the USB-C port only works with a corresponding USB-C to DisplayPort adapter. My original issue is a hardware problem and not a problem with Linux or Fedora!

sampsonf · April 18, 2021, 10:39am

So with a USB-C to DP cable, it works with cold plug but not with hot plug.

It indicates the firmware & driver combination is not mature enough.

chhe · April 18, 2021, 3:53pm

Strange, when I test Fedora as a live system, connecting the screen also works while the system is running (hot plug)

sampsonf · April 18, 2021, 4:49pm

Try install the same version of kernel of the LiveCD to your installed Fedora Linux and see if it helps.

chhe · April 18, 2021, 5:40pm

Ok, it really seems to be a kernel problem. With the currently installed kernel 5.11.14-200.fc33.x86_64 hot plug does not work — only soft plug. If I change to kernel 5.8.15-301.fc33.x86_64 soft and hot plug is working

sampsonf · April 18, 2021, 6:56pm

If you file a bug report about this regression, it will help the kernel team to fix this issue.