devclass_t
extern devclass_t firewire_devclass;
devclass_t pci, pcib;
devclass_t dc;
devclass_t pci;
devclass_t pci_devclass;
static devclass_t an_isa_devclass;
static devclass_t an_pccard_devclass;
extern devclass_t miibus_devclass;
devclass_t device_get_devclass(device_t dev);
devclass_t devclass_find(const char *classname);
device_t devclass_get_device(devclass_t dc, int unit);
int devclass_get_maxunit(devclass_t dc);
devclass_t miibus_devclass;
devclass_t