> usb/probe result: > ep5.0 255 csp 0x0000ff csp 0x0201ff vid 0x1a86 did 0x7523 none <nil> dwcotg
That's a CH341 adapter. I have a driver which should work. You can fetch an updated usb/serial command from http://www.hamnavoe.com/usbserial (use hget). If you want to build from source, updates to /sys/src/cmd/usb/serial are in http://www.hamnavoe.com/serial.tar I would put a patch on sources but the Bell Labs server is unresponsive at present.