diff --git a/sys/arm/arm/nexus.c b/sys/arm/arm/nexus.c
--- a/sys/arm/arm/nexus.c
+++ b/sys/arm/arm/nexus.c
@@ -45,20 +45,20 @@
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/bus.h>
+#include <sys/interrupt.h>
 #include <sys/kernel.h>
 #include <sys/malloc.h>
 #include <sys/module.h>
-#include <machine/bus.h>
 #include <sys/rman.h>
-#include <sys/interrupt.h>
 
-#include <machine/vmparam.h>
-#include <machine/pcb.h>
 #include <vm/vm.h>
 #include <vm/pmap.h>
 
-#include <machine/resource.h>
+#include <machine/bus.h>
+#include <machine/pcb.h>
 #include <machine/intr.h>
+#include <machine/resource.h>
+#include <machine/vmparam.h>
 
 #include <arm/arm/nexusvar.h>
 
@@ -79,37 +79,31 @@
 static struct rman mem_rman;
 static struct rman irq_rman;
 
-static	int nexus_probe(device_t);
-static	int nexus_attach(device_t);
-static	int nexus_print_child(device_t, device_t);
-static	device_t nexus_add_child(device_t, u_int, const char *, int);
-static	struct resource *nexus_alloc_resource(device_t, device_t, int, int *,
-    rman_res_t, rman_res_t, rman_res_t, u_int);
-static	int nexus_activate_resource(device_t, device_t, int, int,
-    struct resource *);
-static	int nexus_adjust_resource(device_t, device_t, int, struct resource *,
-    rman_res_t, rman_res_t);
-static bus_space_tag_t nexus_get_bus_tag(device_t, device_t);
-static bus_dma_tag_t nexus_get_dma_tag(device_t dev, device_t child);
+static device_probe_t		nexus_probe;
+static device_attach_t		nexus_attach;
+
+static bus_add_child_t		nexus_add_child;
+static bus_print_child_t	nexus_print_child;
+
+static bus_activate_resource_t	nexus_activate_resource;
+static bus_adjust_resource_t	nexus_adjust_resource;
+static bus_alloc_resource_t	nexus_alloc_resource;
+static bus_deactivate_resource_t nexus_deactivate_resource;
+static bus_release_resource_t	nexus_release_resource;
+
 #ifdef SMP
-static	int nexus_bind_intr(device_t, device_t, struct resource *, int);
+static bus_bind_intr_t		nexus_bind_intr;
 #endif
-static int nexus_config_intr(device_t dev, int irq, enum intr_trigger trig,
-    enum intr_polarity pol);
-static	int nexus_describe_intr(device_t dev, device_t child,
-    struct resource *irq, void *cookie, const char *descr);
-static	int nexus_deactivate_resource(device_t, device_t, int, int,
-    struct resource *);
-static int nexus_release_resource(device_t, device_t, int, int,
-    struct resource *);
-
-static int nexus_setup_intr(device_t dev, device_t child, struct resource *res,
-    int flags, driver_filter_t *filt, driver_intr_t *intr, void *arg, void **cookiep);
-static int nexus_teardown_intr(device_t, device_t, struct resource *, void *);
+static bus_config_intr_t	nexus_config_intr;
+static bus_describe_intr_t	nexus_describe_intr;
+static bus_setup_intr_t		nexus_setup_intr;
+static bus_teardown_intr_t	nexus_teardown_intr;
+
+static bus_get_bus_tag_t	nexus_get_bus_tag;
+static bus_get_dma_tag_t	nexus_get_dma_tag;
 
 #ifdef FDT
-static int nexus_ofw_map_intr(device_t dev, device_t child, phandle_t iparent,
-    int icells, pcell_t *intr);
+static ofw_bus_map_intr_t	nexus_ofw_map_intr;
 #endif
 
 /*
@@ -123,27 +117,29 @@
 	/* Device interface */
 	DEVMETHOD(device_probe,		nexus_probe),
 	DEVMETHOD(device_attach,	nexus_attach),
+
 	/* Bus interface */
-	DEVMETHOD(bus_print_child,	nexus_print_child),
 	DEVMETHOD(bus_add_child,	nexus_add_child),
-	DEVMETHOD(bus_alloc_resource,	nexus_alloc_resource),
-	DEVMETHOD(bus_activate_resource,	nexus_activate_resource),
+	DEVMETHOD(bus_print_child,	nexus_print_child),
+	DEVMETHOD(bus_activate_resource, nexus_activate_resource),
 	DEVMETHOD(bus_adjust_resource,	nexus_adjust_resource),
-	DEVMETHOD(bus_config_intr,	nexus_config_intr),
-	DEVMETHOD(bus_deactivate_resource,	nexus_deactivate_resource),
+	DEVMETHOD(bus_alloc_resource,	nexus_alloc_resource),
+	DEVMETHOD(bus_deactivate_resource, nexus_deactivate_resource),
 	DEVMETHOD(bus_release_resource,	nexus_release_resource),
+#ifdef SMP
+	DEVMETHOD(bus_bind_intr,	nexus_bind_intr),
+#endif
+	DEVMETHOD(bus_config_intr,	nexus_config_intr),
+	DEVMETHOD(bus_describe_intr,	nexus_describe_intr),
 	DEVMETHOD(bus_setup_intr,	nexus_setup_intr),
 	DEVMETHOD(bus_teardown_intr,	nexus_teardown_intr),
 	DEVMETHOD(bus_get_bus_tag,	nexus_get_bus_tag),
 	DEVMETHOD(bus_get_dma_tag,	nexus_get_dma_tag),
-	DEVMETHOD(bus_describe_intr,	nexus_describe_intr),
-#ifdef SMP
-	DEVMETHOD(bus_bind_intr,	nexus_bind_intr),
-#endif
 #ifdef FDT
+	/* ofw_bus interface */
 	DEVMETHOD(ofw_bus_map_intr,	nexus_ofw_map_intr),
 #endif
-	{ 0, 0 }
+	DEVMETHOD_END
 };
 
 static driver_t nexus_driver = {
@@ -218,7 +214,6 @@
 
 	child = device_add_child_ordered(bus, order, name, unit);
 
-	/* should we free this in nexus_child_detached? */
 	device_set_ivars(child, ndev);
 
 	return (child);
@@ -227,7 +222,6 @@
 /*
  * Allocate a resource on behalf of child.  NB: child is usually going to be a
  * child of one of our descendants, not a direct child of nexus0.
- * (Exceptions include footbridge.)
  */
 static struct resource *
 nexus_alloc_resource(device_t bus, device_t child, int type, int *rid,
@@ -309,9 +303,9 @@
 {
 
 #ifdef FDT
-		return(fdtbus_bs_tag);
+	return (fdtbus_bs_tag);
 #else
-		return((void *)1);
+	return ((void *)1);
 #endif
 }
 
@@ -319,7 +313,7 @@
 nexus_get_dma_tag(device_t dev, device_t child)
 {
 
-	return nexus_dma_tag;
+	return (nexus_dma_tag);
 }
 
 void
@@ -348,7 +342,7 @@
 	if ((rman_get_flags(res) & RF_SHAREABLE) == 0)
 		flags |= INTR_EXCL;
 
-	return(intr_setup_irq(child, res, filt, intr, arg, flags, cookiep));
+	return (intr_setup_irq(child, res, filt, intr, arg, flags, cookiep));
 }
 
 static int