Target fails to enumerate USB-C on KVM

[dsnet]

My symptom is similar to #38 and #62, but I'm filing a new issue since I think I have a concrete diagnosis of the problem. The host side is able to properly enumerate the USB camera and USB serial device. The target fails to enumerate any USB devices when I plug the KVM to the target via a USB-C to USB-C cable.

However, if I plug the USB-C to USB-C cable into a female USB-C to male USB-A adapter and then into a female USB-A to male USB-C adapter, then the target is able to correctly enumerate the HID device (and possibly flash storage if one is attached). I suspect there might be a hardware bug where configuration channel (CC) lines are not correctly terminated with pulldown resistors.

Unlike the NanoKVM (non-USB), I don't see the hardware schematic listed, so I cannot verify.