driver_intr_t
driver_intr_t an_intr;
driver_intr_t, void *arg, const char *name);
driver_filter_t filter, driver_intr_t handler, void *arg,
driver_filter_t filter, void *filter_arg, driver_intr_t handler, void *arg, const char *name)
driver_filter_t* filter, driver_intr_t handler, void *arg, void **_cookie)
driver_intr_t *handler;
driver_filter_t* filter, driver_intr_t handler, void *arg, void **_cookie);
bus_setup_intr(dev, irq, flags, NULL, (driver_intr_t*)func, arg, &ihp);