Of course, looking at the device tree, rapidio is a device, not a bus,
because it does not have a device_type and it does not have any 
children
of its own.

It's a device _of course_, but it's also a bus parent, since
it has a "#address-cells" not equal to zero (and, if this used
real OF, it would have decode-unit and encode-unit methods).
A quite empty bus perhaps heh (in this device tree, anyway).


Segher