Hi,
I managed to get a driver less IAD device working on one of my projects, so I though I should share the config as it's really convenient.
Basically I use and IAD (composite) device with 2 CDC interface, but the second one is declared as custom (bInterfaceClass set to 0) so that windows does not attach it to a serial port.
That way I can use it directly from the software using the GUID.
On the ChibiOS side I use 2 SDU devices.
Code is here:
https://github.com/fpoussin/MotoLink/bl ... b_config.c