where to put USB IDs to?

F.e., a Powercom UPS (0x0d9f:0x0002).  It's
defined in drivers/usb/serial/cypress_m8.h
(and used in drivers/usb/serial/cypress_m8.c)
for now, I'd like to add it to hid blacklist
at drivers/hid/hid-core.c.  So it belongs
to some common place.  The question is which
one.

Thanks.

/mjt