That is easy: plug the USB/Serial CP210x in your Linux machine and run:
# udevadm info -a -n /dev/ttyUSB0 | grep '{serial}' | head -n1
If it is original you will see a complete Unique ID:
# udevadm info -a -n /dev/ttyUSB0 | grep '{serial}' | head -n1
ATTRS{serial}=="201794XXXXXXXa11b392c201cf25bb41"
# udevadm info -a -n /dev/ttyUSB0 | grep '{serial}' | head -n1
ATTRS{serial}=="fe5e32XXXXXXXa119dec3a1dcf25bb41"
If it is fake probably you will see “0001” as Unique ID:
# udevadm info -a -n /dev/ttyUSB0 | grep '{serial}' | head -n1
ATTRS{serial}=="0001"
Thank you. Unfortunately fake chips are proliferating, especially is less sophisticated ICs like the CP2102
Yes, that is true! If you want to make sure it is not fake you need to buy from a certified distributor.
Sorry, this is only true for new CP2102N. Old CP2102 devices were delivered with serial 001 (see datasheet: https://www.silabs.com/documents/public/data-sheets/CP2102-9.pdf, page 17)
Nice! Thanks for explanation Juergen!