Function kernel::drivers::usb_serial::setup_usb_uart

pub fn setup_usb_uart(
    dev: AUsbDevice, 
    ser: ASerialPort
) -> Result<UsbUartParts, ()>

Obtain the “userspace” and “interrupt” portions of the USB-Serial driver

This only returns Ok once, as this driver is a singleton. Subsequent calls will return an Err.