第二台显示器无法通过 USB-C 工作

Question

当我在网上搜索时，我看到了几个类似的问题，但大多数都与 Dock station 有关。我没有使用扩展坞，而是使用 HDMI 转 USB-C 电缆。HDMI 部分连接到外部显示器，USB-C 连接到我的笔记本电脑 (Thinkpad X1 Extreme Gen 2)。该电缆适用于 Windows 操作系统，没有任何问题，但不适用于 Ubuntu。显示器与 HDMI 转 HDMI 电缆配合使用，因此显示器可以正常工作。

我使用了输出journalctl -b，这是插入 USB-C 时的输出；

Mar 31 22:38:11 aydin kernel: usb 1-7: new full-speed USB device number 9 using xhci_hcd
Mar 31 22:38:11 aydin kernel: usb 1-7: not running at top speed; connect to a high speed hub
Mar 31 22:38:11 aydin kernel: usb 1-7: New USB device found, idVendor=25a4, idProduct=9311, bcdDevice= 2.01
Mar 31 22:38:11 aydin kernel: usb 1-7: New USB device strings: Mfr=1, Product=2, SerialNumber=3
Mar 31 22:38:11 aydin kernel: usb 1-7: Product: USB C Video Adaptor      
Mar 31 22:38:11 aydin kernel: usb 1-7: Manufacturer: USB C  
Mar 31 22:38:11 aydin kernel: usb 1-7: SerialNumber: 000000000001
Mar 31 22:38:11 aydin mtp-probe[32822]: checking bus 1, device 9: "/sys/devices/pci0000:00/0000:00:14.0/usb1/1-7"
Mar 31 22:38:11 aydin mtp-probe[32822]: bus: 1, device: 9 was not an MTP device
Mar 31 22:38:11 aydin mtp-probe[32829]: checking bus 1, device 9: "/sys/devices/pci0000:00/0000:00:14.0/usb1/1-7"
Mar 31 22:38:11 aydin mtp-probe[32829]: bus: 1, device: 9 was not an MTP device
Mar 31 22:38:15 aydin kernel: ucsi_acpi USBC000:00: UCSI_GET_PDOS returned 0 bytes

我的xrand输出：

DVI-I-5-4 disconnected (normal left inverted right x axis y axis)
DVI-I-4-3 disconnected (normal left inverted right x axis y axis)
DVI-I-3-2 disconnected (normal left inverted right x axis y axis)
DVI-I-2-1 disconnected (normal left inverted right x axis y axis)
eDP-1-2 disconnected (normal left inverted right x axis y axis)
HDMI-1-1 disconnected (normal left inverted right x axis y axis)
DP-1-1 disconnected (normal left inverted right x axis y axis)
DP-1-2 disconnected (normal left inverted right x axis y axis)
eDP-1 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 344mm x 193mm
   1920x1080     60.01 +  60.01*   59.97    59.96    59.93  
   1680x1050     59.95    59.88  
   1600x1024     60.17  
   1400x1050     59.98  
   1600x900      59.99    59.94    59.95    59.82  
   1280x1024     60.02  
   1440x900      59.89  
   1400x900      59.96    59.88  
   1280x960      60.00  
   1440x810      60.00    59.97  
   1368x768      59.88    59.85  
   1360x768      59.80    59.96  
   1280x800      59.99    59.97    59.81    59.91  
   1152x864      60.00  
   1280x720      60.00    59.99    59.86    59.74  
   1024x768      60.04    60.00  

并且，lshw -C display输出是；

 *-display                 
       description: VGA compatible controller
       product: TU117M [GeForce GTX 1650 Mobile / Max-Q]
       vendor: NVIDIA Corporation
       physical id: 0
       bus info: pci@0000:01:00.0
       version: a1
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress vga_controller bus_master cap_list rom
       configuration: driver=nouveau latency=0
       resources: irq:166 memory:ed000000-edffffff memory:c0000000-cfffffff memory:d0000000-d1ffffff ioport:3000(size=128) memory:ee080000-ee0fffff
  *-display
       description: VGA compatible controller
       product: UHD Graphics 630 (Mobile)
       vendor: Intel Corporation
       physical id: 2
       bus info: pci@0000:00:02.0
       logical name: /dev/fb0
       version: 00
       width: 64 bits
       clock: 33MHz
       capabilities: pciexpress msi pm vga_controller bus_master cap_list fb
       configuration: depth=32 driver=i915 latency=0 mode=1920x1080 visual=truecolor xres=1920 yres=1080
       resources: iomemory:600-5ff iomemory:400-3ff irq:167 memory:6040000000-6040ffffff memory:4000000000-400fffffff ioport:4000(size=64) memory:c0000-dffff

最后，lsusb输出是；

Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 005: ID 06cb:00bd Synaptics, Inc. 
Bus 001 Device 004: ID 04f2:b67d Chicony Electronics Co., Ltd Integrated Camera
Bus 001 Device 009: ID 25a4:9311 USB C   USB C Video Adaptor      
Bus 001 Device 002: ID 1532:005c Razer USA, Ltd Razer DeathAdder Elite
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

正如你所看到的， Bus 001 Device 009: ID 25a4:9311 USB C USB C Video Adaptor Ubuntu 将 USB 识别为视频适配器（我猜），但我在 xrandr 上看不到它。是否可以将 USB-C 添加到 xrandr？可能是什么问题？也许我找不到答案，但我只是想尝试一下:)

Answer 1

我终于找到了解决方案 https://askubuntu.com/a/1134579/1185670

正如“thomasbangels”在那篇文章中提到的，用 nano 编辑该行；

sudo nano /lib/modprobe.d/nvidia-kms.conf

并评论

# This file was generated by nvidia-prime
# Set value to 0 to disable modesetting
# options nvidia-drm modeset=1

然后改变sudo prime-select nvidia就解决了问题。