Import BBB sd driver files from FreeBSD.

3 files changed, 1611 insertions, 0 deletions

diff --git a/freebsd/sys/dev/gpio/gpiobus.c b/freebsd/sys/dev/gpio/gpiobus.c
new file mode 100644
index 00000000..bbe8fc6c
--- /dev/null
+++ b/freebsd/sys/dev/gpio/gpiobus.c
@@ -0,0 +1,862 @@
+#include <machine/rtems-bsd-kernel-space.h>
+
+/*-
+ * Copyright (c) 2009 Oleksandr Tymoshenko <gonzo@freebsd.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/bus.h>
+#include <sys/gpio.h>
+#ifdef INTRNG
+#include <sys/intr.h>
+#endif
+#include <sys/kernel.h>
+#include <sys/malloc.h>
+#include <sys/module.h>
+
+#include <dev/gpio/gpiobusvar.h>
+
+#include <rtems/bsd/local/gpiobus_if.h>
+
+#undef GPIOBUS_DEBUG
+#ifdef GPIOBUS_DEBUG
+#define	dprintf printf
+#else
+#define	dprintf(x, arg...)
+#endif
+
+static void gpiobus_print_pins(struct gpiobus_ivar *, char *, size_t);
+static int gpiobus_parse_pins(struct gpiobus_softc *, device_t, int);
+static int gpiobus_probe(device_t);
+static int gpiobus_attach(device_t);
+static int gpiobus_detach(device_t);
+static int gpiobus_suspend(device_t);
+static int gpiobus_resume(device_t);
+static void gpiobus_probe_nomatch(device_t, device_t);
+static int gpiobus_print_child(device_t, device_t);
+static int gpiobus_child_location_str(device_t, device_t, char *, size_t);
+static int gpiobus_child_pnpinfo_str(device_t, device_t, char *, size_t);
+static device_t gpiobus_add_child(device_t, u_int, const char *, int);
+static void gpiobus_hinted_child(device_t, const char *, int);
+
+/*
+ * GPIOBUS interface
+ */
+static int gpiobus_acquire_bus(device_t, device_t, int);
+static void gpiobus_release_bus(device_t, device_t);
+static int gpiobus_pin_setflags(device_t, device_t, uint32_t, uint32_t);
+static int gpiobus_pin_getflags(device_t, device_t, uint32_t, uint32_t*);
+static int gpiobus_pin_getcaps(device_t, device_t, uint32_t, uint32_t*);
+static int gpiobus_pin_set(device_t, device_t, uint32_t, unsigned int);
+static int gpiobus_pin_get(device_t, device_t, uint32_t, unsigned int*);
+static int gpiobus_pin_toggle(device_t, device_t, uint32_t);
+
+/*
+ * XXX -> Move me to better place - gpio_subr.c?
+ * Also, this function must be changed when interrupt configuration
+ * data will be moved into struct resource.
+ */
+#ifdef INTRNG
+
+struct resource *
+gpio_alloc_intr_resource(device_t consumer_dev, int *rid, u_int alloc_flags,
+    gpio_pin_t pin, uint32_t intr_mode)
+{
+	u_int irq;
+	struct intr_map_data_gpio *gpio_data;
+	struct resource *res;
+
+	gpio_data = (struct intr_map_data_gpio *)intr_alloc_map_data(
+	    INTR_MAP_DATA_GPIO, sizeof(*gpio_data), M_WAITOK | M_ZERO);
+	gpio_data->gpio_pin_num = pin->pin;
+	gpio_data->gpio_pin_flags = pin->flags;
+	gpio_data->gpio_intr_mode = intr_mode;
+
+	irq = intr_map_irq(pin->dev, 0, (struct intr_map_data *)gpio_data);
+	res = bus_alloc_resource(consumer_dev, SYS_RES_IRQ, rid, irq, irq, 1,
+	    alloc_flags);
+	if (res == NULL) {
+		intr_free_intr_map_data((struct intr_map_data *)gpio_data);
+		return (NULL);
+	}
+	rman_set_virtual(res, gpio_data);
+	return (res);
+}
+#else
+struct resource *
+gpio_alloc_intr_resource(device_t consumer_dev, int *rid, u_int alloc_flags,
+    gpio_pin_t pin, uint32_t intr_mode)
+{
+
+	return (NULL);
+}
+#endif
+
+int
+gpio_check_flags(uint32_t caps, uint32_t flags)
+{
+
+	/* Filter unwanted flags. */
+	flags &= caps;
+
+	/* Cannot mix input/output together. */
+	if (flags & GPIO_PIN_INPUT && flags & GPIO_PIN_OUTPUT)
+		return (EINVAL);
+	/* Cannot mix pull-up/pull-down together. */
+	if (flags & GPIO_PIN_PULLUP && flags & GPIO_PIN_PULLDOWN)
+		return (EINVAL);
+
+	return (0);
+}
+
+static void
+gpiobus_print_pins(struct gpiobus_ivar *devi, char *buf, size_t buflen)
+{
+	char tmp[128];
+	int i, range_start, range_stop, need_coma;
+
+	if (devi->npins == 0)
+		return;
+
+	need_coma = 0;
+	range_start = range_stop = devi->pins[0];
+	for (i = 1; i < devi->npins; i++) {
+		if (devi->pins[i] != (range_stop + 1)) {
+			if (need_coma)
+				strlcat(buf, ",", buflen);
+			memset(tmp, 0, sizeof(tmp));
+			if (range_start != range_stop)
+				snprintf(tmp, sizeof(tmp) - 1, "%d-%d",
+				    range_start, range_stop);
+			else
+				snprintf(tmp, sizeof(tmp) - 1, "%d",
+				    range_start);
+			strlcat(buf, tmp, buflen);
+
+			range_start = range_stop = devi->pins[i];
+			need_coma = 1;
+		}
+		else
+			range_stop++;
+	}
+
+	if (need_coma)
+		strlcat(buf, ",", buflen);
+	memset(tmp, 0, sizeof(tmp));
+	if (range_start != range_stop)
+		snprintf(tmp, sizeof(tmp) - 1, "%d-%d",
+		    range_start, range_stop);
+	else
+		snprintf(tmp, sizeof(tmp) - 1, "%d",
+		    range_start);
+	strlcat(buf, tmp, buflen);
+}
+
+device_t
+gpiobus_attach_bus(device_t dev)
+{
+	device_t busdev;
+
+	busdev = device_add_child(dev, "gpiobus", -1);
+	if (busdev == NULL)
+		return (NULL);
+	if (device_add_child(dev, "gpioc", -1) == NULL) {
+		device_delete_child(dev, busdev);
+		return (NULL);
+	}
+#ifdef FDT
+	ofw_gpiobus_register_provider(dev);
+#endif
+	bus_generic_attach(dev);
+
+	return (busdev);
+}
+
+int
+gpiobus_detach_bus(device_t dev)
+{
+	int err;
+
+#ifdef FDT
+	ofw_gpiobus_unregister_provider(dev);
+#endif
+	err = bus_generic_detach(dev);
+	if (err != 0)
+		return (err);
+
+	return (device_delete_children(dev));
+}
+
+int
+gpiobus_init_softc(device_t dev)
+{
+	struct gpiobus_softc *sc;
+
+	sc = GPIOBUS_SOFTC(dev);
+	sc->sc_busdev = dev;
+	sc->sc_dev = device_get_parent(dev);
+	sc->sc_intr_rman.rm_type = RMAN_ARRAY;
+	sc->sc_intr_rman.rm_descr = "GPIO Interrupts";
+	if (rman_init(&sc->sc_intr_rman) != 0 ||
+	    rman_manage_region(&sc->sc_intr_rman, 0, ~0) != 0)
+		panic("%s: failed to set up rman.", __func__);
+
+	if (GPIO_PIN_MAX(sc->sc_dev, &sc->sc_npins) != 0)
+		return (ENXIO);
+
+	KASSERT(sc->sc_npins >= 0, ("GPIO device with no pins"));
+
+	/* Pins = GPIO_PIN_MAX() + 1 */
+	sc->sc_npins++;
+
+	sc->sc_pins = malloc(sizeof(*sc->sc_pins) * sc->sc_npins, M_DEVBUF,
+	    M_NOWAIT | M_ZERO);
+	if (sc->sc_pins == NULL)
+		return (ENOMEM);
+
+	/* Initialize the bus lock. */
+	GPIOBUS_LOCK_INIT(sc);
+
+	return (0);
+}
+
+int
+gpiobus_alloc_ivars(struct gpiobus_ivar *devi)
+{
+
+	/* Allocate pins and flags memory. */
+	devi->pins = malloc(sizeof(uint32_t) * devi->npins, M_DEVBUF,
+	    M_NOWAIT | M_ZERO);
+	if (devi->pins == NULL)
+		return (ENOMEM);
+	devi->flags = malloc(sizeof(uint32_t) * devi->npins, M_DEVBUF,
+	    M_NOWAIT | M_ZERO);
+	if (devi->flags == NULL) {
+		free(devi->pins, M_DEVBUF);
+		return (ENOMEM);
+	}
+
+	return (0);
+}
+
+void
+gpiobus_free_ivars(struct gpiobus_ivar *devi)
+{
+
+	if (devi->flags) {
+		free(devi->flags, M_DEVBUF);
+		devi->flags = NULL;
+	}
+	if (devi->pins) {
+		free(devi->pins, M_DEVBUF);
+		devi->pins = NULL;
+	}
+}
+
+int
+gpiobus_acquire_pin(device_t bus, uint32_t pin)
+{
+	struct gpiobus_softc *sc;
+
+	sc = device_get_softc(bus);
+	/* Consistency check. */
+	if (pin >= sc->sc_npins) {
+		device_printf(bus,
+		    "invalid pin %d, max: %d\n", pin, sc->sc_npins - 1);
+		return (-1);
+	}
+	/* Mark pin as mapped and give warning if it's already mapped. */
+	if (sc->sc_pins[pin].mapped) {
+		device_printf(bus, "warning: pin %d is already mapped\n", pin);
+		return (-1);
+	}
+	sc->sc_pins[pin].mapped = 1;
+
+	return (0);
+}
+
+/* Release mapped pin */
+int
+gpiobus_release_pin(device_t bus, uint32_t pin)
+{
+	struct gpiobus_softc *sc;
+
+	sc = device_get_softc(bus);
+	/* Consistency check. */
+	if (pin >= sc->sc_npins) {
+		device_printf(bus,
+		    "gpiobus_acquire_pin: invalid pin %d, max=%d\n",
+		    pin, sc->sc_npins - 1);
+		return (-1);
+	}
+
+	if (!sc->sc_pins[pin].mapped) {
+		device_printf(bus, "gpiobus_acquire_pin: pin %d is not mapped\n", pin);
+		return (-1);
+	}
+	sc->sc_pins[pin].mapped = 0;
+
+	return (0);
+}
+
+static int
+gpiobus_parse_pins(struct gpiobus_softc *sc, device_t child, int mask)
+{
+	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
+	int i, npins;
+
+	npins = 0;
+	for (i = 0; i < 32; i++) {
+		if (mask & (1 << i))
+			npins++;
+	}
+	if (npins == 0) {
+		device_printf(child, "empty pin mask\n");
+		return (EINVAL);
+	}
+	devi->npins = npins;
+	if (gpiobus_alloc_ivars(devi) != 0) {
+		device_printf(child, "cannot allocate device ivars\n");
+		return (EINVAL);
+	}
+	npins = 0;
+	for (i = 0; i < 32; i++) {
+		if ((mask & (1 << i)) == 0)
+			continue;
+		/* Reserve the GPIO pin. */
+		if (gpiobus_acquire_pin(sc->sc_busdev, i) != 0) {
+			gpiobus_free_ivars(devi);
+			return (EINVAL);
+		}
+		devi->pins[npins++] = i;
+		/* Use the child name as pin name. */
+		GPIOBUS_PIN_SETNAME(sc->sc_busdev, i,
+		    device_get_nameunit(child));
+	}
+
+	return (0);
+}
+
+static int
+gpiobus_probe(device_t dev)
+{
+	device_set_desc(dev, "GPIO bus");
+
+	return (BUS_PROBE_GENERIC);
+}
+
+static int
+gpiobus_attach(device_t dev)
+{
+	int err;
+
+	err = gpiobus_init_softc(dev);
+	if (err != 0)
+		return (err);
+
+	/*
+	 * Get parent's pins and mark them as unmapped
+	 */
+	bus_generic_probe(dev);
+	bus_enumerate_hinted_children(dev);
+
+	return (bus_generic_attach(dev));
+}
+
+/*
+ * Since this is not a self-enumerating bus, and since we always add
+ * children in attach, we have to always delete children here.
+ */
+static int
+gpiobus_detach(device_t dev)
+{
+	struct gpiobus_softc *sc;
+	struct gpiobus_ivar *devi;
+	device_t *devlist;
+	int i, err, ndevs;
+
+	sc = GPIOBUS_SOFTC(dev);
+	KASSERT(mtx_initialized(&sc->sc_mtx),
+	    ("gpiobus mutex not initialized"));
+	GPIOBUS_LOCK_DESTROY(sc);
+
+	if ((err = bus_generic_detach(dev)) != 0)
+		return (err);
+
+	if ((err = device_get_children(dev, &devlist, &ndevs)) != 0)
+		return (err);
+	for (i = 0; i < ndevs; i++) {
+		devi = GPIOBUS_IVAR(devlist[i]);
+		gpiobus_free_ivars(devi);
+		resource_list_free(&devi->rl);
+		free(devi, M_DEVBUF);
+		device_delete_child(dev, devlist[i]);
+	}
+	free(devlist, M_TEMP);
+	rman_fini(&sc->sc_intr_rman);
+	if (sc->sc_pins) {
+		for (i = 0; i < sc->sc_npins; i++) {
+			if (sc->sc_pins[i].name != NULL)
+				free(sc->sc_pins[i].name, M_DEVBUF);
+			sc->sc_pins[i].name = NULL;
+		}
+		free(sc->sc_pins, M_DEVBUF);
+		sc->sc_pins = NULL;
+	}
+
+	return (0);
+}
+
+static int
+gpiobus_suspend(device_t dev)
+{
+
+	return (bus_generic_suspend(dev));
+}
+
+static int
+gpiobus_resume(device_t dev)
+{
+
+	return (bus_generic_resume(dev));
+}
+
+static void
+gpiobus_probe_nomatch(device_t dev, device_t child)
+{
+	char pins[128];
+	struct gpiobus_ivar *devi;
+
+	devi = GPIOBUS_IVAR(child);
+	memset(pins, 0, sizeof(pins));
+	gpiobus_print_pins(devi, pins, sizeof(pins));
+	if (devi->npins > 1)
+		device_printf(dev, "<unknown device> at pins %s", pins);
+	else
+		device_printf(dev, "<unknown device> at pin %s", pins);
+	resource_list_print_type(&devi->rl, "irq", SYS_RES_IRQ, "%jd");
+	printf("\n");
+}
+
+static int
+gpiobus_print_child(device_t dev, device_t child)
+{
+	char pins[128];
+	int retval = 0;
+	struct gpiobus_ivar *devi;
+
+	devi = GPIOBUS_IVAR(child);
+	memset(pins, 0, sizeof(pins));
+	retval += bus_print_child_header(dev, child);
+	if (devi->npins > 0) {
+		if (devi->npins > 1)
+			retval += printf(" at pins ");
+		else
+			retval += printf(" at pin ");
+		gpiobus_print_pins(devi, pins, sizeof(pins));
+		retval += printf("%s", pins);
+	}
+	resource_list_print_type(&devi->rl, "irq", SYS_RES_IRQ, "%jd");
+	retval += bus_print_child_footer(dev, child);
+
+	return (retval);
+}
+
+static int
+gpiobus_child_location_str(device_t bus, device_t child, char *buf,
+    size_t buflen)
+{
+	struct gpiobus_ivar *devi;
+
+	devi = GPIOBUS_IVAR(child);
+	if (devi->npins > 1)
+		strlcpy(buf, "pins=", buflen);
+	else
+		strlcpy(buf, "pin=", buflen);
+	gpiobus_print_pins(devi, buf, buflen);
+
+	return (0);
+}
+
+static int
+gpiobus_child_pnpinfo_str(device_t bus, device_t child, char *buf,
+    size_t buflen)
+{
+
+	*buf = '\0';
+	return (0);
+}
+
+static device_t
+gpiobus_add_child(device_t dev, u_int order, const char *name, int unit)
+{
+	device_t child;
+	struct gpiobus_ivar *devi;
+
+	child = device_add_child_ordered(dev, order, name, unit);
+	if (child == NULL) 
+		return (child);
+	devi = malloc(sizeof(struct gpiobus_ivar), M_DEVBUF, M_NOWAIT | M_ZERO);
+	if (devi == NULL) {
+		device_delete_child(dev, child);
+		return (NULL);
+	}
+	resource_list_init(&devi->rl);
+	device_set_ivars(child, devi);
+
+	return (child);
+}
+
+static void
+gpiobus_hinted_child(device_t bus, const char *dname, int dunit)
+{
+	struct gpiobus_softc *sc = GPIOBUS_SOFTC(bus);
+	struct gpiobus_ivar *devi;
+	device_t child;
+	int irq, pins;
+
+	child = BUS_ADD_CHILD(bus, 0, dname, dunit);
+	devi = GPIOBUS_IVAR(child);
+	resource_int_value(dname, dunit, "pins", &pins);
+	if (gpiobus_parse_pins(sc, child, pins)) {
+		resource_list_free(&devi->rl);
+		free(devi, M_DEVBUF);
+		device_delete_child(bus, child);
+	}
+	if (resource_int_value(dname, dunit, "irq", &irq) == 0) {
+		if (bus_set_resource(child, SYS_RES_IRQ, 0, irq, 1) != 0)
+			device_printf(bus,
+			    "warning: bus_set_resource() failed\n");
+	}
+}
+
+static int
+gpiobus_set_resource(device_t dev, device_t child, int type, int rid,
+    rman_res_t start, rman_res_t count)
+{
+	struct gpiobus_ivar *devi;
+	struct resource_list_entry *rle;
+
+	dprintf("%s: entry (%p, %p, %d, %d, %p, %ld)\n",
+	    __func__, dev, child, type, rid, (void *)(intptr_t)start, count);
+	devi = GPIOBUS_IVAR(child);
+	rle = resource_list_add(&devi->rl, type, rid, start,
+	    start + count - 1, count);
+	if (rle == NULL)
+		return (ENXIO);
+
+	return (0);
+}
+
+static struct resource *
+gpiobus_alloc_resource(device_t bus, device_t child, int type, int *rid,
+    rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
+{
+	struct gpiobus_softc *sc;
+	struct resource *rv;
+	struct resource_list *rl;
+	struct resource_list_entry *rle;
+	int isdefault;
+
+	if (type != SYS_RES_IRQ)
+		return (NULL);
+	isdefault = (RMAN_IS_DEFAULT_RANGE(start, end) && count == 1);
+	rle = NULL;
+	if (isdefault) {
+		rl = BUS_GET_RESOURCE_LIST(bus, child);
+		if (rl == NULL)
+			return (NULL);
+		rle = resource_list_find(rl, type, *rid);
+		if (rle == NULL)
+			return (NULL);
+		if (rle->res != NULL)
+			panic("%s: resource entry is busy", __func__);
+		start = rle->start;
+		count = rle->count;
+		end = rle->end;
+	}
+	sc = device_get_softc(bus);
+	rv = rman_reserve_resource(&sc->sc_intr_rman, start, end, count, flags,
+	    child);
+	if (rv == NULL)
+		return (NULL);
+	rman_set_rid(rv, *rid);
+	if ((flags & RF_ACTIVE) != 0 &&
+	    bus_activate_resource(child, type, *rid, rv) != 0) {
+		rman_release_resource(rv);
+		return (NULL);
+	}
+
+	return (rv);
+}
+
+static int
+gpiobus_release_resource(device_t bus __unused, device_t child, int type,
+    int rid, struct resource *r)
+{
+	int error;
+
+	if (rman_get_flags(r) & RF_ACTIVE) {
+		error = bus_deactivate_resource(child, type, rid, r);
+		if (error)
+			return (error);
+	}
+
+	return (rman_release_resource(r));
+}
+
+static struct resource_list *
+gpiobus_get_resource_list(device_t bus __unused, device_t child)
+{
+	struct gpiobus_ivar *ivar;
+
+	ivar = GPIOBUS_IVAR(child);
+
+	return (&ivar->rl);
+}
+
+static int
+gpiobus_acquire_bus(device_t busdev, device_t child, int how)
+{
+	struct gpiobus_softc *sc;
+
+	sc = device_get_softc(busdev);
+	GPIOBUS_ASSERT_UNLOCKED(sc);
+	GPIOBUS_LOCK(sc);
+	if (sc->sc_owner != NULL) {
+		if (sc->sc_owner == child)
+			panic("%s: %s still owns the bus.",
+			    device_get_nameunit(busdev),
+			    device_get_nameunit(child));
+		if (how == GPIOBUS_DONTWAIT) {
+			GPIOBUS_UNLOCK(sc);
+			return (EWOULDBLOCK);
+		}
+		while (sc->sc_owner != NULL)
+			mtx_sleep(sc, &sc->sc_mtx, 0, "gpiobuswait", 0);
+	}
+	sc->sc_owner = child;
+	GPIOBUS_UNLOCK(sc);
+
+	return (0);
+}
+
+static void
+gpiobus_release_bus(device_t busdev, device_t child)
+{
+	struct gpiobus_softc *sc;
+
+	sc = device_get_softc(busdev);
+	GPIOBUS_ASSERT_UNLOCKED(sc);
+	GPIOBUS_LOCK(sc);
+	if (sc->sc_owner == NULL)
+		panic("%s: %s releasing unowned bus.",
+		    device_get_nameunit(busdev),
+		    device_get_nameunit(child));
+	if (sc->sc_owner != child)
+		panic("%s: %s trying to release bus owned by %s",
+		    device_get_nameunit(busdev),
+		    device_get_nameunit(child),
+		    device_get_nameunit(sc->sc_owner));
+	sc->sc_owner = NULL;
+	wakeup(sc);
+	GPIOBUS_UNLOCK(sc);
+}
+
+static int
+gpiobus_pin_setflags(device_t dev, device_t child, uint32_t pin, 
+    uint32_t flags)
+{
+	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
+	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
+	uint32_t caps;
+
+	if (pin >= devi->npins)
+		return (EINVAL);
+	if (GPIO_PIN_GETCAPS(sc->sc_dev, devi->pins[pin], &caps) != 0)
+		return (EINVAL);
+	if (gpio_check_flags(caps, flags) != 0)
+		return (EINVAL);
+
+	return (GPIO_PIN_SETFLAGS(sc->sc_dev, devi->pins[pin], flags));
+}
+
+static int
+gpiobus_pin_getflags(device_t dev, device_t child, uint32_t pin, 
+    uint32_t *flags)
+{
+	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
+	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
+
+	if (pin >= devi->npins)
+		return (EINVAL);
+
+	return GPIO_PIN_GETFLAGS(sc->sc_dev, devi->pins[pin], flags);
+}
+
+static int
+gpiobus_pin_getcaps(device_t dev, device_t child, uint32_t pin, 
+    uint32_t *caps)
+{
+	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
+	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
+
+	if (pin >= devi->npins)
+		return (EINVAL);
+
+	return GPIO_PIN_GETCAPS(sc->sc_dev, devi->pins[pin], caps);
+}
+
+static int
+gpiobus_pin_set(device_t dev, device_t child, uint32_t pin, 
+    unsigned int value)
+{
+	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
+	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
+
+	if (pin >= devi->npins)
+		return (EINVAL);
+
+	return GPIO_PIN_SET(sc->sc_dev, devi->pins[pin], value);
+}
+
+static int
+gpiobus_pin_get(device_t dev, device_t child, uint32_t pin, 
+    unsigned int *value)
+{
+	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
+	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
+
+	if (pin >= devi->npins)
+		return (EINVAL);
+
+	return GPIO_PIN_GET(sc->sc_dev, devi->pins[pin], value);
+}
+
+static int
+gpiobus_pin_toggle(device_t dev, device_t child, uint32_t pin)
+{
+	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
+	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
+
+	if (pin >= devi->npins)
+		return (EINVAL);
+
+	return GPIO_PIN_TOGGLE(sc->sc_dev, devi->pins[pin]);
+}
+
+static int
+gpiobus_pin_getname(device_t dev, uint32_t pin, char *name)
+{
+	struct gpiobus_softc *sc;
+
+	sc = GPIOBUS_SOFTC(dev);
+	if (pin > sc->sc_npins)
+		return (EINVAL);
+	/* Did we have a name for this pin ? */
+	if (sc->sc_pins[pin].name != NULL) {
+		memcpy(name, sc->sc_pins[pin].name, GPIOMAXNAME);
+		return (0);
+	}
+
+	/* Return the default pin name. */
+	return (GPIO_PIN_GETNAME(device_get_parent(dev), pin, name));
+}
+
+static int
+gpiobus_pin_setname(device_t dev, uint32_t pin, const char *name)
+{
+	struct gpiobus_softc *sc;
+
+	sc = GPIOBUS_SOFTC(dev);
+	if (pin > sc->sc_npins)
+		return (EINVAL);
+	if (name == NULL)
+		return (EINVAL);
+	/* Save the pin name. */
+	if (sc->sc_pins[pin].name == NULL)
+		sc->sc_pins[pin].name = malloc(GPIOMAXNAME, M_DEVBUF,
+		    M_WAITOK | M_ZERO);
+	strlcpy(sc->sc_pins[pin].name, name, GPIOMAXNAME);
+
+	return (0);
+}
+
+static device_method_t gpiobus_methods[] = {
+	/* Device interface */
+	DEVMETHOD(device_probe,		gpiobus_probe),
+	DEVMETHOD(device_attach,	gpiobus_attach),
+	DEVMETHOD(device_detach,	gpiobus_detach),
+	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
+	DEVMETHOD(device_suspend,	gpiobus_suspend),
+	DEVMETHOD(device_resume,	gpiobus_resume),
+
+	/* Bus interface */
+	DEVMETHOD(bus_setup_intr,	bus_generic_setup_intr),
+	DEVMETHOD(bus_config_intr,	bus_generic_config_intr),
+	DEVMETHOD(bus_teardown_intr,	bus_generic_teardown_intr),
+	DEVMETHOD(bus_set_resource,	gpiobus_set_resource),
+	DEVMETHOD(bus_alloc_resource,	gpiobus_alloc_resource),
+	DEVMETHOD(bus_release_resource,	gpiobus_release_resource),
+	DEVMETHOD(bus_activate_resource,	bus_generic_activate_resource),
+	DEVMETHOD(bus_deactivate_resource,	bus_generic_deactivate_resource),
+	DEVMETHOD(bus_get_resource_list,	gpiobus_get_resource_list),
+	DEVMETHOD(bus_add_child,	gpiobus_add_child),
+	DEVMETHOD(bus_probe_nomatch,	gpiobus_probe_nomatch),
+	DEVMETHOD(bus_print_child,	gpiobus_print_child),
+	DEVMETHOD(bus_child_pnpinfo_str, gpiobus_child_pnpinfo_str),
+	DEVMETHOD(bus_child_location_str, gpiobus_child_location_str),
+	DEVMETHOD(bus_hinted_child,	gpiobus_hinted_child),
+
+	/* GPIO protocol */
+	DEVMETHOD(gpiobus_acquire_bus,	gpiobus_acquire_bus),
+	DEVMETHOD(gpiobus_release_bus,	gpiobus_release_bus),
+	DEVMETHOD(gpiobus_pin_getflags,	gpiobus_pin_getflags),
+	DEVMETHOD(gpiobus_pin_getcaps,	gpiobus_pin_getcaps),
+	DEVMETHOD(gpiobus_pin_setflags,	gpiobus_pin_setflags),
+	DEVMETHOD(gpiobus_pin_get,	gpiobus_pin_get),
+	DEVMETHOD(gpiobus_pin_set,	gpiobus_pin_set),
+	DEVMETHOD(gpiobus_pin_toggle,	gpiobus_pin_toggle),
+	DEVMETHOD(gpiobus_pin_getname,	gpiobus_pin_getname),
+	DEVMETHOD(gpiobus_pin_setname,	gpiobus_pin_setname),
+
+	DEVMETHOD_END
+};
+
+driver_t gpiobus_driver = {
+	"gpiobus",
+	gpiobus_methods,
+	sizeof(struct gpiobus_softc)
+};
+
+devclass_t	gpiobus_devclass;
+
+EARLY_DRIVER_MODULE(gpiobus, gpio, gpiobus_driver, gpiobus_devclass, 0, 0,
+    BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE);
+MODULE_VERSION(gpiobus, 1);
diff --git a/freebsd/sys/dev/gpio/gpiobusvar.h b/freebsd/sys/dev/gpio/gpiobusvar.h
new file mode 100644
index 00000000..9eee5a03
--- /dev/null
+++ b/freebsd/sys/dev/gpio/gpiobusvar.h
@@ -0,0 +1,156 @@
+/*-
+ * Copyright (c) 2009 Oleksandr Tymoshenko <gonzo@freebsd.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ *
+ */
+
+#ifndef	__GPIOBUS_H__
+#define	__GPIOBUS_H__
+
+#include <rtems/bsd/local/opt_platform.h>
+
+#include <sys/lock.h>
+#include <sys/mutex.h>
+#include <sys/rman.h>
+
+#ifdef FDT
+#include <dev/ofw/ofw_bus_subr.h>
+#endif
+
+#ifdef	INTRNG
+#include <sys/intr.h>
+#endif
+
+#include <rtems/bsd/local/gpio_if.h>
+
+#ifdef FDT
+#define	GPIOBUS_IVAR(d) (struct gpiobus_ivar *)				\
+	&((struct ofw_gpiobus_devinfo *)device_get_ivars(d))->opd_dinfo
+#else
+#define	GPIOBUS_IVAR(d) (struct gpiobus_ivar *) device_get_ivars(d)
+#endif
+#define	GPIOBUS_SOFTC(d) (struct gpiobus_softc *) device_get_softc(d)
+#define	GPIOBUS_LOCK(_sc) mtx_lock(&(_sc)->sc_mtx)
+#define	GPIOBUS_UNLOCK(_sc) mtx_unlock(&(_sc)->sc_mtx)
+#define	GPIOBUS_LOCK_INIT(_sc) mtx_init(&_sc->sc_mtx,			\
+	    device_get_nameunit(_sc->sc_dev), "gpiobus", MTX_DEF)
+#define	GPIOBUS_LOCK_DESTROY(_sc) mtx_destroy(&_sc->sc_mtx)
+#define	GPIOBUS_ASSERT_LOCKED(_sc) mtx_assert(&_sc->sc_mtx, MA_OWNED)
+#define	GPIOBUS_ASSERT_UNLOCKED(_sc) mtx_assert(&_sc->sc_mtx, MA_NOTOWNED)
+
+#define	GPIOBUS_WAIT		1
+#define	GPIOBUS_DONTWAIT	2
+
+/* Use default interrupt mode -  for gpio_alloc_intr_resource */
+#define GPIO_INTR_CONFORM	GPIO_INTR_NONE
+
+struct gpiobus_pin_data
+{
+	int		mapped;		/* pin is mapped/reserved. */
+	char		*name;		/* pin name. */
+};
+
+#ifdef INTRNG
+struct intr_map_data_gpio {
+	struct intr_map_data	hdr;
+	u_int			gpio_pin_num;
+	u_int			gpio_pin_flags;
+	u_int		 	gpio_intr_mode;
+};
+#endif
+
+struct gpiobus_softc
+{
+	struct mtx	sc_mtx;		/* bus mutex */
+	struct rman	sc_intr_rman;	/* isr resources */
+	device_t	sc_busdev;	/* bus device */
+	device_t	sc_owner;	/* bus owner */
+	device_t	sc_dev;		/* driver device */
+	int		sc_npins;	/* total pins on bus */
+	struct gpiobus_pin_data	*sc_pins; /* pin data */
+};
+
+struct gpiobus_pin
+{
+	device_t	dev;	/* gpio device */
+	uint32_t	flags;	/* pin flags */
+	uint32_t	pin;	/* pin number */
+};
+typedef struct gpiobus_pin *gpio_pin_t;
+
+struct gpiobus_ivar
+{
+	struct resource_list	rl;	/* isr resource list */
+	uint32_t	npins;	/* pins total */
+	uint32_t	*flags;	/* pins flags */
+	uint32_t	*pins;	/* pins map */
+};
+
+#ifdef FDT
+struct ofw_gpiobus_devinfo {
+	struct gpiobus_ivar	opd_dinfo;
+	struct ofw_bus_devinfo	opd_obdinfo;
+};
+
+static __inline int
+gpio_map_gpios(device_t bus, phandle_t dev, phandle_t gparent, int gcells,
+    pcell_t *gpios, uint32_t *pin, uint32_t *flags)
+{
+	return (GPIO_MAP_GPIOS(bus, dev, gparent, gcells, gpios, pin, flags));
+}
+
+device_t ofw_gpiobus_add_fdt_child(device_t, const char *, phandle_t);
+int ofw_gpiobus_parse_gpios(device_t, char *, struct gpiobus_pin **);
+void ofw_gpiobus_register_provider(device_t);
+void ofw_gpiobus_unregister_provider(device_t);
+
+/* Consumers interface. */
+int gpio_pin_get_by_ofw_name(device_t consumer, phandle_t node,
+    char *name, gpio_pin_t *gpio);
+int gpio_pin_get_by_ofw_idx(device_t consumer, phandle_t node,
+    int idx, gpio_pin_t *gpio);
+int gpio_pin_get_by_ofw_property(device_t consumer, phandle_t node,
+    char *name, gpio_pin_t *gpio);
+void gpio_pin_release(gpio_pin_t gpio);
+int gpio_pin_getcaps(gpio_pin_t pin, uint32_t *caps);
+int gpio_pin_is_active(gpio_pin_t pin, bool *active);
+int gpio_pin_set_active(gpio_pin_t pin, bool active);
+int gpio_pin_setflags(gpio_pin_t pin, uint32_t flags);
+#endif
+struct resource *gpio_alloc_intr_resource(device_t consumer_dev, int *rid,
+    u_int alloc_flags, gpio_pin_t pin, uint32_t intr_mode);
+int gpio_check_flags(uint32_t, uint32_t);
+device_t gpiobus_attach_bus(device_t);
+int gpiobus_detach_bus(device_t);
+int gpiobus_init_softc(device_t);
+int gpiobus_alloc_ivars(struct gpiobus_ivar *);
+void gpiobus_free_ivars(struct gpiobus_ivar *);
+int gpiobus_acquire_pin(device_t, uint32_t);
+int gpiobus_release_pin(device_t, uint32_t);
+
+extern driver_t gpiobus_driver;
+
+#endif	/* __GPIOBUS_H__ */
diff --git a/freebsd/sys/dev/gpio/ofw_gpiobus.c b/freebsd/sys/dev/gpio/ofw_gpiobus.c
new file mode 100644
index 00000000..24e9477c
--- /dev/null
+++ b/freebsd/sys/dev/gpio/ofw_gpiobus.c
@@ -0,0 +1,593 @@
+#include <machine/rtems-bsd-kernel-space.h>
+
+/*-
+ * Copyright (c) 2009, Nathan Whitehorn <nwhitehorn@FreeBSD.org>
+ * Copyright (c) 2013, Luiz Otavio O Souza <loos@FreeBSD.org>
+ * Copyright (c) 2013 The FreeBSD Foundation
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice unmodified, this list of conditions, and the following
+ *    disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/bus.h>
+#include <sys/kernel.h>
+#include <sys/malloc.h>
+#include <sys/module.h>
+
+#include <dev/gpio/gpiobusvar.h>
+#include <dev/ofw/ofw_bus.h>
+
+#include <rtems/bsd/local/gpiobus_if.h>
+
+#define	GPIO_ACTIVE_LOW		1
+
+static struct ofw_gpiobus_devinfo *ofw_gpiobus_setup_devinfo(device_t,
+	device_t, phandle_t);
+static void ofw_gpiobus_destroy_devinfo(device_t, struct ofw_gpiobus_devinfo *);
+static int ofw_gpiobus_parse_gpios_impl(device_t, phandle_t, char *,
+	struct gpiobus_softc *, struct gpiobus_pin **);
+
+/*
+ * Utility functions for easier handling of OFW GPIO pins.
+ *
+ * !!! BEWARE !!!
+ * GPIOBUS uses children's IVARs, so we cannot use this interface for cross
+ * tree consumers.
+ *
+ */
+static int
+gpio_pin_get_by_ofw_impl(device_t consumer, phandle_t cnode,
+    char *prop_name, int idx, gpio_pin_t *out_pin)
+{
+	phandle_t xref;
+	pcell_t *cells;
+	device_t busdev;
+	struct gpiobus_pin pin;
+	int ncells, rv;
+
+	KASSERT(consumer != NULL && cnode > 0,
+	    ("both consumer and cnode required"));
+
+	rv = ofw_bus_parse_xref_list_alloc(cnode, prop_name, "#gpio-cells",
+	    idx, &xref, &ncells, &cells);
+	if (rv != 0)
+		return (rv);
+
+	/* Translate provider to device. */
+	pin.dev = OF_device_from_xref(xref);
+	if (pin.dev == NULL) {
+		OF_prop_free(cells);
+		return (ENODEV);
+	}
+
+	/* Test if GPIO bus already exist. */
+	busdev = GPIO_GET_BUS(pin.dev);
+	if (busdev == NULL) {
+		OF_prop_free(cells);
+		return (ENODEV);
+	}
+
+	/* Map GPIO pin. */
+	rv = gpio_map_gpios(pin.dev, cnode, OF_node_from_xref(xref), ncells,
+	    cells, &pin.pin, &pin.flags);
+	OF_prop_free(cells);
+	if (rv != 0)
+		return (ENXIO);
+
+	/* Reserve GPIO pin. */
+	rv = gpiobus_acquire_pin(busdev, pin.pin);
+	if (rv != 0)
+		return (EBUSY);
+
+	*out_pin = malloc(sizeof(struct gpiobus_pin), M_DEVBUF,
+	    M_WAITOK | M_ZERO);
+	**out_pin = pin;
+	return (0);
+}
+
+int
+gpio_pin_get_by_ofw_idx(device_t consumer, phandle_t node,
+    int idx, gpio_pin_t *pin)
+{
+
+	return (gpio_pin_get_by_ofw_impl(consumer, node, "gpios", idx, pin));
+}
+
+int
+gpio_pin_get_by_ofw_property(device_t consumer, phandle_t node,
+    char *name, gpio_pin_t *pin)
+{
+
+	return (gpio_pin_get_by_ofw_impl(consumer, node, name, 0, pin));
+}
+
+int
+gpio_pin_get_by_ofw_name(device_t consumer, phandle_t node,
+    char *name, gpio_pin_t *pin)
+{
+	int rv, idx;
+
+	KASSERT(consumer != NULL && node > 0,
+	    ("both consumer and node required"));
+
+	rv = ofw_bus_find_string_index(node, "gpio-names", name, &idx);
+	if (rv != 0)
+		return (rv);
+	return (gpio_pin_get_by_ofw_idx(consumer, node, idx, pin));
+}
+
+void
+gpio_pin_release(gpio_pin_t gpio)
+{
+	device_t busdev;
+
+	if (gpio == NULL)
+		return;
+
+	KASSERT(gpio->dev != NULL, ("invalid pin state"));
+
+	busdev = GPIO_GET_BUS(gpio->dev);
+	if (busdev != NULL)
+		gpiobus_release_pin(busdev, gpio->pin);
+
+	/* XXXX Unreserve pin. */
+	free(gpio, M_DEVBUF);
+}
+
+int
+gpio_pin_getcaps(gpio_pin_t pin, uint32_t *caps)
+{
+
+	KASSERT(pin != NULL, ("GPIO pin is NULL."));
+	KASSERT(pin->dev != NULL, ("GPIO pin device is NULL."));
+	return (GPIO_PIN_GETCAPS(pin->dev, pin->pin, caps));
+}
+
+int
+gpio_pin_is_active(gpio_pin_t pin, bool *active)
+{
+	int rv;
+	uint32_t tmp;
+
+	KASSERT(pin != NULL, ("GPIO pin is NULL."));
+	KASSERT(pin->dev != NULL, ("GPIO pin device is NULL."));
+	rv = GPIO_PIN_GET(pin->dev, pin->pin, &tmp);
+	if (rv  != 0) {
+		return (rv);
+	}
+
+	if (pin->flags & GPIO_ACTIVE_LOW)
+		*active = tmp == 0;
+	else
+		*active = tmp != 0;
+	return (0);
+}
+
+int
+gpio_pin_set_active(gpio_pin_t pin, bool active)
+{
+	int rv;
+	uint32_t tmp;
+
+	if (pin->flags & GPIO_ACTIVE_LOW)
+		tmp = active ? 0 : 1;
+	else
+		tmp = active ? 1 : 0;
+
+	KASSERT(pin != NULL, ("GPIO pin is NULL."));
+	KASSERT(pin->dev != NULL, ("GPIO pin device is NULL."));
+	rv = GPIO_PIN_SET(pin->dev, pin->pin, tmp);
+	return (rv);
+}
+
+int
+gpio_pin_setflags(gpio_pin_t pin, uint32_t flags)
+{
+	int rv;
+
+	KASSERT(pin != NULL, ("GPIO pin is NULL."));
+	KASSERT(pin->dev != NULL, ("GPIO pin device is NULL."));
+
+	rv = GPIO_PIN_SETFLAGS(pin->dev, pin->pin, flags);
+	return (rv);
+}
+
+/*
+ * OFW_GPIOBUS driver.
+ */
+device_t
+ofw_gpiobus_add_fdt_child(device_t bus, const char *drvname, phandle_t child)
+{
+	device_t childdev;
+	int i;
+	struct gpiobus_ivar *devi;
+	struct ofw_gpiobus_devinfo *dinfo;
+
+	/*
+	 * Check to see if we already have a child for @p child, and if so
+	 * return it.
+	 */
+	childdev = ofw_bus_find_child_device_by_phandle(bus, child);
+	if (childdev != NULL)
+		return (childdev);
+
+	/*
+	 * Set up the GPIO child and OFW bus layer devinfo and add it to bus.
+	 */
+	childdev = device_add_child(bus, drvname, -1);
+	if (childdev == NULL)
+		return (NULL);
+	dinfo = ofw_gpiobus_setup_devinfo(bus, childdev, child);
+	if (dinfo == NULL) {
+		device_delete_child(bus, childdev);
+		return (NULL);
+	}
+	if (device_probe_and_attach(childdev) != 0) {
+		ofw_gpiobus_destroy_devinfo(bus, dinfo);
+		device_delete_child(bus, childdev);
+		return (NULL);
+	}
+	/* Use the child name as pin name. */
+	devi = &dinfo->opd_dinfo;
+	for (i = 0; i < devi->npins; i++)
+		GPIOBUS_PIN_SETNAME(bus, devi->pins[i],
+		    device_get_nameunit(childdev));
+
+	return (childdev);
+}
+
+int
+ofw_gpiobus_parse_gpios(device_t consumer, char *pname,
+	struct gpiobus_pin **pins)
+{
+
+	return (ofw_gpiobus_parse_gpios_impl(consumer,
+	    ofw_bus_get_node(consumer), pname, NULL, pins));
+}
+
+void
+ofw_gpiobus_register_provider(device_t provider)
+{
+	phandle_t node;
+
+	node = ofw_bus_get_node(provider);
+	OF_device_register_xref(OF_xref_from_node(node), provider);
+}
+
+void
+ofw_gpiobus_unregister_provider(device_t provider)
+{
+	phandle_t node;
+
+	node = ofw_bus_get_node(provider);
+	OF_device_register_xref(OF_xref_from_node(node), NULL);
+}
+
+static struct ofw_gpiobus_devinfo *
+ofw_gpiobus_setup_devinfo(device_t bus, device_t child, phandle_t node)
+{
+	int i, npins;
+	struct gpiobus_ivar *devi;
+	struct gpiobus_pin *pins;
+	struct gpiobus_softc *sc;
+	struct ofw_gpiobus_devinfo *dinfo;
+
+	sc = device_get_softc(bus);
+	dinfo = malloc(sizeof(*dinfo), M_DEVBUF, M_NOWAIT | M_ZERO);
+	if (dinfo == NULL)
+		return (NULL);
+	if (ofw_bus_gen_setup_devinfo(&dinfo->opd_obdinfo, node) != 0) {
+		free(dinfo, M_DEVBUF);
+		return (NULL);
+	}
+	/* Parse the gpios property for the child. */
+	npins = ofw_gpiobus_parse_gpios_impl(child, node, "gpios", sc, &pins);
+	if (npins <= 0) {
+		ofw_bus_gen_destroy_devinfo(&dinfo->opd_obdinfo);
+		free(dinfo, M_DEVBUF);
+		return (NULL);
+	}
+	/* Initialize the irq resource list. */
+	resource_list_init(&dinfo->opd_dinfo.rl);
+	/* Allocate the child ivars and copy the parsed pin data. */
+	devi = &dinfo->opd_dinfo;
+	devi->npins = (uint32_t)npins;
+	if (gpiobus_alloc_ivars(devi) != 0) {
+		free(pins, M_DEVBUF);
+		ofw_gpiobus_destroy_devinfo(bus, dinfo);
+		return (NULL);
+	}
+	for (i = 0; i < devi->npins; i++) {
+		devi->flags[i] = pins[i].flags;
+		devi->pins[i] = pins[i].pin;
+	}
+	free(pins, M_DEVBUF);
+	/* Parse the interrupt resources. */
+	if (ofw_bus_intr_to_rl(bus, node, &dinfo->opd_dinfo.rl, NULL) != 0) {
+		ofw_gpiobus_destroy_devinfo(bus, dinfo);
+		return (NULL);
+	}
+	device_set_ivars(child, dinfo);
+
+	return (dinfo);
+}
+
+static void
+ofw_gpiobus_destroy_devinfo(device_t bus, struct ofw_gpiobus_devinfo *dinfo)
+{
+	int i;
+	struct gpiobus_ivar *devi;
+	struct gpiobus_softc *sc;
+
+	sc = device_get_softc(bus);
+	devi = &dinfo->opd_dinfo;
+	for (i = 0; i < devi->npins; i++) {
+		if (devi->pins[i] > sc->sc_npins)
+			continue;
+		sc->sc_pins[devi->pins[i]].mapped = 0;
+	}
+	gpiobus_free_ivars(devi);
+	resource_list_free(&dinfo->opd_dinfo.rl);
+	ofw_bus_gen_destroy_devinfo(&dinfo->opd_obdinfo);
+	free(dinfo, M_DEVBUF);
+}
+
+static int
+ofw_gpiobus_parse_gpios_impl(device_t consumer, phandle_t cnode, char *pname,
+	struct gpiobus_softc *bussc, struct gpiobus_pin **pins)
+{
+	int gpiocells, i, j, ncells, npins;
+	pcell_t *gpios;
+	phandle_t gpio;
+
+	ncells = OF_getencprop_alloc(cnode, pname, sizeof(*gpios),
+            (void **)&gpios);
+	if (ncells == -1) {
+		device_printf(consumer,
+		    "Warning: No %s specified in fdt data; "
+		    "device may not function.\n", pname);
+		return (-1);
+	}
+	/*
+	 * The gpio-specifier is controller independent, the first pcell has
+	 * the reference to the GPIO controller phandler.
+	 * Count the number of encoded gpio-specifiers on the first pass.
+	 */
+	i = 0;
+	npins = 0;
+	while (i < ncells) {
+		/* Allow NULL specifiers. */
+		if (gpios[i] == 0) {
+			npins++;
+			i++;
+			continue;
+		}
+		gpio = OF_node_from_xref(gpios[i]);
+		/* If we have bussc, ignore devices from other gpios. */
+		if (bussc != NULL)
+			if (ofw_bus_get_node(bussc->sc_dev) != gpio)
+				return (0);
+		/*
+		 * Check for gpio-controller property and read the #gpio-cells
+		 * for this GPIO controller.
+		 */
+		if (!OF_hasprop(gpio, "gpio-controller") ||
+		    OF_getencprop(gpio, "#gpio-cells", &gpiocells,
+		    sizeof(gpiocells)) < 0) {
+			device_printf(consumer,
+			    "gpio reference is not a gpio-controller.\n");
+			OF_prop_free(gpios);
+			return (-1);
+		}
+		if (ncells - i < gpiocells + 1) {
+			device_printf(consumer,
+			    "%s cells doesn't match #gpio-cells.\n", pname);
+			return (-1);
+		}
+		npins++;
+		i += gpiocells + 1;
+	}
+	if (npins == 0 || pins == NULL) {
+		if (npins == 0)
+			device_printf(consumer, "no pin specified in %s.\n",
+			    pname);
+		OF_prop_free(gpios);
+		return (npins);
+	}
+	*pins = malloc(sizeof(struct gpiobus_pin) * npins, M_DEVBUF,
+	    M_NOWAIT | M_ZERO);
+	if (*pins == NULL) {
+		OF_prop_free(gpios);
+		return (-1);
+	}
+	/* Decode the gpio specifier on the second pass. */
+	i = 0;
+	j = 0;
+	while (i < ncells) {
+		/* Allow NULL specifiers. */
+		if (gpios[i] == 0) {
+			j++;
+			i++;
+			continue;
+		}
+		gpio = OF_node_from_xref(gpios[i]);
+		/* Read gpio-cells property for this GPIO controller. */
+		if (OF_getencprop(gpio, "#gpio-cells", &gpiocells,
+		    sizeof(gpiocells)) < 0) {
+			device_printf(consumer,
+			    "gpio does not have the #gpio-cells property.\n");
+			goto fail;
+		}
+		/* Return the device reference for the GPIO controller. */
+		(*pins)[j].dev = OF_device_from_xref(gpios[i]);
+		if ((*pins)[j].dev == NULL) {
+			device_printf(consumer,
+			    "no device registered for the gpio controller.\n");
+			goto fail;
+		}
+		/*
+		 * If the gpiobus softc is NULL we use the GPIO_GET_BUS() to
+		 * retrieve it.  The GPIO_GET_BUS() method is only valid after
+		 * the child is probed and attached.
+		 */
+		if (bussc == NULL) {
+			if (GPIO_GET_BUS((*pins)[j].dev) == NULL) {
+				device_printf(consumer,
+				    "no gpiobus reference for %s.\n",
+				    device_get_nameunit((*pins)[j].dev));
+				goto fail;
+			}
+			bussc = device_get_softc(GPIO_GET_BUS((*pins)[j].dev));
+		}
+		/* Get the GPIO pin number and flags. */
+		if (gpio_map_gpios((*pins)[j].dev, cnode, gpio, gpiocells,
+		    &gpios[i + 1], &(*pins)[j].pin, &(*pins)[j].flags) != 0) {
+			device_printf(consumer,
+			    "cannot map the gpios specifier.\n");
+			goto fail;
+		}
+		/* Reserve the GPIO pin. */
+		if (gpiobus_acquire_pin(bussc->sc_busdev, (*pins)[j].pin) != 0)
+			goto fail;
+		j++;
+		i += gpiocells + 1;
+	}
+	OF_prop_free(gpios);
+
+	return (npins);
+
+fail:
+	OF_prop_free(gpios);
+	free(*pins, M_DEVBUF);
+	return (-1);
+}
+
+static int
+ofw_gpiobus_probe(device_t dev)
+{
+
+	if (ofw_bus_get_node(dev) == -1)
+		return (ENXIO);
+	device_set_desc(dev, "OFW GPIO bus");
+
+	return (0);
+}
+
+static int
+ofw_gpiobus_attach(device_t dev)
+{
+	int err;
+	phandle_t child;
+
+	err = gpiobus_init_softc(dev);
+	if (err != 0)
+		return (err);
+	bus_generic_probe(dev);
+	bus_enumerate_hinted_children(dev);
+	/*
+	 * Attach the children represented in the device tree.
+	 */
+	for (child = OF_child(ofw_bus_get_node(dev)); child != 0;
+	    child = OF_peer(child)) {
+		if (!OF_hasprop(child, "gpios"))
+			continue;
+		if (ofw_gpiobus_add_fdt_child(dev, NULL, child) == NULL)
+			continue;
+	}
+
+	return (bus_generic_attach(dev));
+}
+
+static device_t
+ofw_gpiobus_add_child(device_t dev, u_int order, const char *name, int unit)
+{
+	device_t child;
+	struct ofw_gpiobus_devinfo *devi;
+
+	child = device_add_child_ordered(dev, order, name, unit);
+	if (child == NULL)
+		return (child);
+	devi = malloc(sizeof(struct ofw_gpiobus_devinfo), M_DEVBUF,
+	    M_NOWAIT | M_ZERO);
+	if (devi == NULL) {
+		device_delete_child(dev, child);
+		return (0);
+	}
+
+	/*
+	 * NULL all the OFW-related parts of the ivars for non-OFW
+	 * children.
+	 */
+	devi->opd_obdinfo.obd_node = -1;
+	devi->opd_obdinfo.obd_name = NULL;
+	devi->opd_obdinfo.obd_compat = NULL;
+	devi->opd_obdinfo.obd_type = NULL;
+	devi->opd_obdinfo.obd_model = NULL;
+
+	device_set_ivars(child, devi);
+
+	return (child);
+}
+
+static const struct ofw_bus_devinfo *
+ofw_gpiobus_get_devinfo(device_t bus, device_t dev)
+{
+	struct ofw_gpiobus_devinfo *dinfo;
+
+	dinfo = device_get_ivars(dev);
+
+	return (&dinfo->opd_obdinfo);
+}
+
+static device_method_t ofw_gpiobus_methods[] = {
+	/* Device interface */
+	DEVMETHOD(device_probe,		ofw_gpiobus_probe),
+	DEVMETHOD(device_attach,	ofw_gpiobus_attach),
+
+	/* Bus interface */
+	DEVMETHOD(bus_child_pnpinfo_str,	ofw_bus_gen_child_pnpinfo_str),
+	DEVMETHOD(bus_add_child,	ofw_gpiobus_add_child),
+
+	/* ofw_bus interface */
+	DEVMETHOD(ofw_bus_get_devinfo,	ofw_gpiobus_get_devinfo),
+	DEVMETHOD(ofw_bus_get_compat,	ofw_bus_gen_get_compat),
+	DEVMETHOD(ofw_bus_get_model,	ofw_bus_gen_get_model),
+	DEVMETHOD(ofw_bus_get_name,	ofw_bus_gen_get_name),
+	DEVMETHOD(ofw_bus_get_node,	ofw_bus_gen_get_node),
+	DEVMETHOD(ofw_bus_get_type,	ofw_bus_gen_get_type),
+
+	DEVMETHOD_END
+};
+
+devclass_t ofwgpiobus_devclass;
+
+DEFINE_CLASS_1(gpiobus, ofw_gpiobus_driver, ofw_gpiobus_methods,
+    sizeof(struct gpiobus_softc), gpiobus_driver);
+EARLY_DRIVER_MODULE(ofw_gpiobus, gpio, ofw_gpiobus_driver, ofwgpiobus_devclass,
+    0, 0, BUS_PASS_BUS);
+MODULE_VERSION(ofw_gpiobus, 1);
+MODULE_DEPEND(ofw_gpiobus, gpiobus, 1, 1, 1);