I am looking for an easy way to retrieve the OpenFirmware node (phandle)
of a struct device * I get passed in device_register(). Is there any magic
way to store them in the device properties early?

I'm trying to avoid code like this:

void
device_register(struct device *dev, void *aux)
{
	struct device * parent = device_parent(dev);
	int node

	if (parent == NULL) {
		/* handle mainbus devices ... */
	} else if (device_is_a(parent, "pci")) {
		struct pci_attach_args *pa = aux;
		/* MD way to extract OF node from pa->pa_tag */
		node = ..
	} else if ....

	/* do something with node */
}

Is there some better way than adding the property in various ${bus}_machdep
functions? How could I do it for things like scsibus or atapibus?

Martin