Hi Martin,
Thanks for the suggestion but I was able to work with our friends at ADI to get the spec. for the USBi USB protocol. Using these documents I was able to use libusb (under both Linux and Windows) to duplicate the functionality that is provided through Sigma Studio. I've written a Python package that runs under Linux that provides access through the USBi adapter for I2C and theoretically SPI (although SPI remains untested). We've integrated it into our tooling to provide some of the same functions to read/write to/from nodes and peripherals. I actually prototyped discovery on my Linux laptop with a short Python script using this approach and ADI's evaluation boards.
I understand from Lars that ADI is reluctant to release the USBi protocol spec. to the general public due to support concerns. If, however, you or your colleagues are interested in the Python source code, just let me know. I suspect in scenarios where Sigma Studio might not be appropriate and an Aardvark is not available, it might be a useful tool.
Thanks,
Glenn