dmesg -w 

[ 1999.689678] usb 2-4: new full-speed USB device number 3 using ohci-pci
[ 1999.919763] usb 2-4: New USB device found, idVendor=067b, idProduct=2303, bcdDevice=5d.ca
[ 1999.919772] usb 2-4: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[ 1999.919775] usb 2-4: Product: USB-Serial Controller
[ 1999.919777] usb 2-4: Manufacturer: Prolific Technology Inc.
[ 1999.923348] pl2303 2-4:1.0: pl2303 converter detected
[ 1999.923365] pl2303 2-4:1.0: unknown device type, please report to linux-usb@vger.kernel.org