- If the atkbdc device is assigned an IRQ resource by ACPI or the PnPBIOS,

allow the child atkbd device to reuse that IRQ resource instead of
  reallocating the same IRQ from the parent bus inside the atkbd driver.
- Don't allocate a shared IRQ for the atkbd driver.  For AT keyboard
  devices on an ISA bus the IRQ is not shareable.  Instead, the bus driver
  should mark the IRQ shareable if the bus supports shared IRQs.
- Don't identify child devices until after the atkbdc device itself has
  attached.

sys/dev/atkbdc/atkbd_atkbdc.c

@@ -94,8 +94,7 @@ atkbdprobe(device_t dev)
 
 	/* see if IRQ is available */
 	rid = KBDC_RID_KBD;
-	res = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid,
-				     RF_SHAREABLE | RF_ACTIVE);
+	res = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid, RF_ACTIVE);
 	if (res == NULL) {
 		if (bootverbose)
 			device_printf(dev, "unable to allocate IRQ\n");
@@ -132,8 +131,7 @@ atkbdattach(device_t dev)
 		return error;
 
 	/* declare our interrupt handler */
-	sc->intr = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid,
-					  RF_SHAREABLE | RF_ACTIVE);
+	sc->intr = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid, RF_ACTIVE);
 	if (sc->intr == NULL)
 		return ENXIO;
 	error = bus_setup_intr(dev, sc->intr, INTR_TYPE_TTY, NULL, atkbdintr,

sys/dev/atkbdc/atkbdc_isa.c

@@ -49,6 +49,11 @@ static int	atkbdc_isa_probe(device_t dev);
 static int	atkbdc_isa_attach(device_t dev);
 static device_t	atkbdc_isa_add_child(device_t bus, u_int order, const char *name,
 		    int unit);
+static struct resource *atkbdc_isa_alloc_resource(device_t dev, device_t child,
+		    int type, int *rid, u_long start, u_long end,
+		    u_long count, u_int flags);
+static int	atkbdc_isa_release_resource(device_t dev, device_t child,
+		    int type, int rid, struct resource *r);
 
 static device_method_t atkbdc_isa_methods[] = {
 	DEVMETHOD(device_probe,		atkbdc_isa_probe),
@@ -61,8 +66,8 @@ static device_method_t atkbdc_isa_methods[] = {
 	DEVMETHOD(bus_read_ivar,	atkbdc_read_ivar),
 	DEVMETHOD(bus_write_ivar,	atkbdc_write_ivar),
 	DEVMETHOD(bus_get_resource_list,atkbdc_get_resource_list),
-	DEVMETHOD(bus_alloc_resource,	bus_generic_rl_alloc_resource),
-	DEVMETHOD(bus_release_resource,	bus_generic_rl_release_resource),
+	DEVMETHOD(bus_alloc_resource,	atkbdc_isa_alloc_resource),
+	DEVMETHOD(bus_release_resource,	atkbdc_isa_release_resource),
 	DEVMETHOD(bus_activate_resource, bus_generic_activate_resource),
 	DEVMETHOD(bus_deactivate_resource, bus_generic_deactivate_resource),
 	DEVMETHOD(bus_get_resource,	bus_generic_rl_get_resource),
@@ -170,8 +175,6 @@ atkbdc_isa_probe(device_t dev)
 	device_verbose(dev);
 
 	error = atkbdc_probe_unit(device_get_unit(dev), port0, port1);
-	if (error == 0)
-		bus_generic_probe(dev);
 
 	bus_release_resource(dev, SYS_RES_IOPORT, 0, port0);
 	bus_release_resource(dev, SYS_RES_IOPORT, 1, port1);
@@ -216,14 +219,25 @@ atkbdc_isa_attach(device_t dev)
 		return ENXIO;
 	}
 
+	/*
+	 * If the device is not created by the PnP BIOS or ACPI, then
+	 * the hint for the IRQ is on the child atkbd device, not the
+	 * keyboard controller, so this can fail.
+	 */
+	rid = 0;
+	sc->irq = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid, RF_ACTIVE);
+
 	error = atkbdc_attach_unit(unit, sc, sc->port0, sc->port1);
 	if (error) {
 		bus_release_resource(dev, SYS_RES_IOPORT, 0, sc->port0);
 		bus_release_resource(dev, SYS_RES_IOPORT, 1, sc->port1);
+		if (sc->irq != NULL)
+			bus_release_resource(dev, SYS_RES_IRQ, 0, sc->irq);
 		return error;
 	}
 	*(atkbdc_softc_t **)device_get_softc(dev) = sc;
 
+	bus_generic_probe(dev);
 	bus_generic_attach(dev);
 
 	return 0;
@@ -233,9 +247,11 @@ static device_t
 atkbdc_isa_add_child(device_t bus, u_int order, const char *name, int unit)
 {
 	atkbdc_device_t	*ivar;
+	atkbdc_softc_t	*sc;
 	device_t	child;
 	int		t;
 
+	sc = *(atkbdc_softc_t **)device_get_softc(bus);
 	ivar = malloc(sizeof(struct atkbdc_device), M_ATKBDDEV,
 		M_NOWAIT | M_ZERO);
 	if (!ivar)
@@ -251,15 +267,16 @@ atkbdc_isa_add_child(device_t bus, u_int order, const char *name, int unit)
 	ivar->rid = order;
 
 	/*
-	 * If the device is not created by the PnP BIOS or ACPI,
-	 * refer to device hints for IRQ.
+	 * If the device is not created by the PnP BIOS or ACPI, refer
+	 * to device hints for IRQ.  We always populate the resource
+	 * list entry so we can use a standard bus_get_resource()
+	 * method.
 	 */
-	if (ISA_PNP_PROBE(device_get_parent(bus), bus, atkbdc_ids) != 0) {
+	if (sc->irq == NULL) {
 		if (resource_int_value(name, unit, "irq", &t) != 0)
 			t = -1;
-	} else {
-		t = bus_get_resource_start(bus, SYS_RES_IRQ, ivar->rid);
-	}
+	} else
+		t = rman_get_start(sc->irq);
 	if (t > 0)
 		resource_list_add(&ivar->resources, SYS_RES_IRQ, ivar->rid,
 				  t, t, 1);
@@ -272,5 +289,30 @@ atkbdc_isa_add_child(device_t bus, u_int order, const char *name, int unit)
 	return child;
 }
 
+struct resource *
+atkbdc_isa_alloc_resource(device_t dev, device_t child, int type, int *rid,
+    u_long start, u_long end, u_long count, u_int flags)
+{
+	atkbdc_softc_t	*sc;
+	
+	sc = *(atkbdc_softc_t **)device_get_softc(dev);
+	if (type == SYS_RES_IRQ && *rid == KBDC_RID_KBD && sc->irq != NULL)
+		return (sc->irq);
+	return (bus_generic_rl_alloc_resource(dev, child, type, rid, start,
+	    end, count, flags));
+}
+
+static int
+atkbdc_isa_release_resource(device_t dev, device_t child, int type, int rid,
+    struct resource *r)
+{
+	atkbdc_softc_t	*sc;
+	
+	sc = *(atkbdc_softc_t **)device_get_softc(dev);
+	if (type == SYS_RES_IRQ && rid == KBDC_RID_KBD && r == sc->irq)
+		return (0);
+	return (bus_generic_rl_release_resource(dev, child, type, rid, r));
+}
+
 DRIVER_MODULE(atkbdc, isa, atkbdc_isa_driver, atkbdc_devclass, 0, 0);
 DRIVER_MODULE(atkbdc, acpi, atkbdc_isa_driver, atkbdc_devclass, 0, 0);

sys/dev/atkbdc/atkbdcreg.h

@@ -192,6 +192,7 @@ struct resource;
 typedef struct atkbdc_softc {
     struct resource *port0;	/* data port */
     struct resource *port1;	/* status port */
+    struct resource *irq;
     bus_space_tag_t iot;
     bus_space_handle_t ioh0;
     bus_space_handle_t ioh1;