Linux doesn't have any driver for the "RP2040" in the abstract - you have to design the USB device you want (which you could implement on any other USB capable

Linux doesn't have any driver for the "RP2040" in the abstract - you have to design the USB device you want (which you could implement on any other USB capable microcontroller as well usually.) You can use the standard USB CDC classes with the RP2040 to obtain Linux support without writing your own driver - but you still have to build this. You can only access the USB boot ROM after programming if you are able to toggle the boot selection pins with the host CPU's GPIO - no idea if that's connected here.