I needed a small USB to TTL serial converter (1.5 x 2 cm). i found one with a CP2102, but dat dit not work very well with linux. That's why i made a new one with the FT I chip FT232RL Schematic is designed using TinyCAD and for the PCB i used FreePCB PCB is now being made by OSHpark.com.
You must have a very old kernel or something, the Linux driver has been in the kernel sources since 2.6.12. https://www.silabs.com/community/interface/knowledge-base.entry.html/2012/12/21/cp210x_driver_inthe-Ojpw