2 files changed, 910 insertions, 67 deletions

diff --git a/sys/dev/gpio/gpiobus.c b/sys/dev/gpio/gpiobus.c
index bd0bae96b1df..e1f74d81955e 100644
--- a/sys/dev/gpio/gpiobus.c
+++ b/sys/dev/gpio/gpiobus.c
@@ -143,6 +143,15 @@ gpio_check_flags(uint32_t caps, uint32_t flags)
 	/* Cannot mix pull-up/pull-down together. */
 	if (flags & GPIO_PIN_PULLUP && flags & GPIO_PIN_PULLDOWN)
 		return (EINVAL);
+	/* Cannot mix output and interrupt flags together */
+	if (flags & GPIO_PIN_OUTPUT && flags & GPIO_INTR_MASK)
+		return (EINVAL);
+	/* Only one interrupt flag can be defined at once */
+	if ((flags & GPIO_INTR_MASK) & ((flags & GPIO_INTR_MASK) - 1))
+		return (EINVAL);
+	/* The interrupt attached flag cannot be set */
+	if (flags & GPIO_INTR_ATTACHED)
+		return (EINVAL);
 
 	return (0);
 }
diff --git a/sys/dev/gpio/gpioc.c b/sys/dev/gpio/gpioc.c
index dfa421ed49af..727b07a70589 100644
--- a/sys/dev/gpio/gpioc.c
+++ b/sys/dev/gpio/gpioc.c
@@ -35,8 +35,15 @@ __FBSDID("$FreeBSD$");
 #include <sys/conf.h>
 #include <sys/gpio.h>
 #include <sys/ioccom.h>
+#include <sys/filio.h>
+#include <sys/fcntl.h>
+#include <sys/sigio.h>
+#include <sys/signalvar.h>
 #include <sys/kernel.h>
 #include <sys/malloc.h>
+#include <sys/uio.h>
+#include <sys/poll.h>
+#include <sys/selinfo.h>
 #include <sys/module.h>
 
 #include <dev/gpio/gpiobusvar.h>
@@ -47,29 +54,509 @@ __FBSDID("$FreeBSD$");
 #undef GPIOC_DEBUG
 #ifdef GPIOC_DEBUG
 #define dprintf printf
+#define ddevice_printf device_printf
 #else
 #define dprintf(x, arg...)
+#define ddevice_printf(dev, x, arg...)
 #endif
 
-static int gpioc_probe(device_t dev);
-static int gpioc_attach(device_t dev);
-static int gpioc_detach(device_t dev);
+struct gpioc_softc {
+	device_t		sc_dev;		/* gpiocX dev */
+	device_t		sc_pdev;	/* gpioX dev */
+	struct cdev		*sc_ctl_dev;	/* controller device */
+	int			sc_unit;
+	int			sc_npins;
+	struct gpioc_pin_intr	*sc_pin_intr;
+};
+
+struct gpioc_pin_intr {
+	struct gpioc_softc				*sc;
+	gpio_pin_t					pin;
+	bool						config_locked;
+	int						intr_rid;
+	struct resource					*intr_res;
+	void						*intr_cookie;
+	struct mtx					mtx;
+	SLIST_HEAD(gpioc_privs_list, gpioc_privs)	privs;
+};
+
+
+struct gpioc_cdevpriv {
+	struct gpioc_softc			*sc;
+	struct selinfo				selinfo;
+	bool					async;
+	uint8_t					report_option;
+	struct sigio				*sigio;
+	struct mtx				mtx;
+	struct gpioc_pin_event			*events;
+	int					numevents;
+	int					evidx_head;
+	int					evidx_tail;
+	SLIST_HEAD(gpioc_pins_list, gpioc_pins)	pins;
+};
+
+struct gpioc_privs {
+	struct gpioc_cdevpriv		*priv;
+	SLIST_ENTRY(gpioc_privs)	next;
+};
+
+struct gpioc_pins {
+	struct gpioc_pin_intr	*pin;
+	int			eventcount;
+	int			firstevent;
+	SLIST_ENTRY(gpioc_pins)	next;
+};
+
+struct gpioc_pin_event {
+	struct gpioc_pins	*privpin;
+	sbintime_t		event_time;
+	bool			event_pin_state;
+};
+
+static MALLOC_DEFINE(M_GPIOC, "gpioc", "gpioc device data");
 
+static int	gpioc_allocate_pin_intr(struct gpioc_pin_intr*, uint32_t);
+static int	gpioc_release_pin_intr(struct gpioc_pin_intr*);
+static int	gpioc_attach_priv_pin(struct gpioc_cdevpriv*,
+		    struct gpioc_pin_intr*);
+static int	gpioc_detach_priv_pin(struct gpioc_cdevpriv*,
+		    struct gpioc_pin_intr*);
+static bool	gpioc_intr_reconfig_allowed(struct gpioc_cdevpriv*,
+		    struct gpioc_pin_intr *intr_conf);
+static uint32_t	gpioc_get_intr_config(struct gpioc_softc*,
+		    struct gpioc_cdevpriv*, uint32_t pin);
+static int	gpioc_set_intr_config(struct gpioc_softc*,
+		    struct gpioc_cdevpriv*, uint32_t, uint32_t);
+static void	gpioc_interrupt_handler(void*);
+
+static int	gpioc_kqread(struct knote*, long);
+static void	gpioc_kqdetach(struct knote*);
+
+static int	gpioc_probe(device_t dev);
+static int	gpioc_attach(device_t dev);
+static int	gpioc_detach(device_t dev);
+
+static void	gpioc_cdevpriv_dtor(void*);
+
+static d_open_t		gpioc_open;
+static d_read_t		gpioc_read;
 static d_ioctl_t	gpioc_ioctl;
+static d_poll_t		gpioc_poll;
+static d_kqfilter_t	gpioc_kqfilter;
 
 static struct cdevsw gpioc_cdevsw = {
 	.d_version	= D_VERSION,
+	.d_open		= gpioc_open,
+	.d_read		= gpioc_read,
 	.d_ioctl	= gpioc_ioctl,
+	.d_poll		= gpioc_poll,
+	.d_kqfilter	= gpioc_kqfilter,
 	.d_name		= "gpioc",
 };
 
-struct gpioc_softc {
-	device_t	sc_dev;		/* gpiocX dev */
-	device_t	sc_pdev;	/* gpioX dev */
-	struct cdev	*sc_ctl_dev;	/* controller device */
-	int		sc_unit;
+static struct filterops gpioc_read_filterops = {
+	.f_isfd =	true,
+	.f_attach =	NULL,
+	.f_detach =	gpioc_kqdetach,
+	.f_event =	gpioc_kqread,
+	.f_touch =	NULL
 };
 
+static struct gpioc_pin_event *
+next_head_event(struct gpioc_cdevpriv *priv)
+{
+	struct gpioc_pin_event *rv;
+
+	rv = &priv->events[priv->evidx_head++];
+	if (priv->evidx_head == priv->numevents)
+		priv->evidx_head = 0;
+	return (rv);
+}
+
+static struct gpioc_pin_event *
+next_tail_event(struct gpioc_cdevpriv *priv)
+{
+	struct gpioc_pin_event *rv;
+
+	rv = &priv->events[priv->evidx_tail++];
+	if (priv->evidx_tail == priv->numevents)
+		priv->evidx_tail = 0;
+	return (rv);
+}
+
+static size_t
+number_of_events(struct gpioc_cdevpriv *priv)
+{
+	if (priv->evidx_head >= priv->evidx_tail)
+		return (priv->evidx_head - priv->evidx_tail);
+	else
+		return (priv->numevents + priv->evidx_head - priv->evidx_tail);
+}
+
+static int
+gpioc_allocate_pin_intr(struct gpioc_pin_intr *intr_conf, uint32_t flags)
+{
+	int err;
+
+	intr_conf->config_locked = true;
+	mtx_unlock(&intr_conf->mtx);
+
+	intr_conf->intr_res = gpio_alloc_intr_resource(intr_conf->pin->dev,
+	    &intr_conf->intr_rid, RF_ACTIVE, intr_conf->pin, flags);
+	if (intr_conf->intr_res == NULL) {
+		err = ENXIO;
+		goto error_exit;
+	}
+
+	err = bus_setup_intr(intr_conf->pin->dev, intr_conf->intr_res,
+	    INTR_TYPE_MISC | INTR_MPSAFE, NULL, gpioc_interrupt_handler,
+	    intr_conf, &intr_conf->intr_cookie);
+	if (err != 0)
+		goto error_exit;
+
+	intr_conf->pin->flags = flags;
+
+error_exit:
+	mtx_lock(&intr_conf->mtx);
+	intr_conf->config_locked = false;
+	wakeup(&intr_conf->config_locked);
+
+	return (err);
+}
+
+static int
+gpioc_release_pin_intr(struct gpioc_pin_intr *intr_conf)
+{
+	int err;
+
+	intr_conf->config_locked = true;
+	mtx_unlock(&intr_conf->mtx);
+
+	if (intr_conf->intr_cookie != NULL) {
+		err = bus_teardown_intr(intr_conf->pin->dev,
+		    intr_conf->intr_res, intr_conf->intr_cookie);
+		if (err != 0)
+			goto error_exit;
+		else
+			intr_conf->intr_cookie = NULL;
+	}
+
+	if (intr_conf->intr_res != NULL) {
+		err = bus_release_resource(intr_conf->pin->dev, SYS_RES_IRQ,
+		    intr_conf->intr_rid, intr_conf->intr_res);
+		if (err != 0)
+			goto error_exit;
+		else {
+			intr_conf->intr_rid = 0;
+			intr_conf->intr_res = NULL;
+		}
+	}
+
+	intr_conf->pin->flags = 0;
+	err = 0;
+
+error_exit:
+	mtx_lock(&intr_conf->mtx);
+	intr_conf->config_locked = false;
+	wakeup(&intr_conf->config_locked);
+
+	return (err);
+}
+
+static int
+gpioc_attach_priv_pin(struct gpioc_cdevpriv *priv,
+    struct gpioc_pin_intr *intr_conf)
+{
+	struct gpioc_privs	*priv_link;
+	struct gpioc_pins	*pin_link;
+	unsigned int		consistency_a, consistency_b;
+
+	consistency_a = 0;
+	consistency_b = 0;
+	mtx_assert(&intr_conf->mtx, MA_OWNED);
+	mtx_lock(&priv->mtx);
+	SLIST_FOREACH(priv_link, &intr_conf->privs, next) {
+		if (priv_link->priv == priv)
+			consistency_a++;
+	}
+	KASSERT(consistency_a <= 1,
+	    ("inconsistent links between pin config and cdevpriv"));
+	SLIST_FOREACH(pin_link, &priv->pins, next) {
+		if (pin_link->pin == intr_conf)
+			consistency_b++;
+	}
+	KASSERT(consistency_a == consistency_b,
+	    ("inconsistent links between pin config and cdevpriv"));
+	if (consistency_a == 1 && consistency_b == 1) {
+		mtx_unlock(&priv->mtx);
+		return (EEXIST);
+	}
+	priv_link = malloc(sizeof(struct gpioc_privs), M_GPIOC,
+	    M_NOWAIT | M_ZERO);
+	if (priv_link == NULL)
+	{
+		mtx_unlock(&priv->mtx);
+		return (ENOMEM);
+	}
+	pin_link = malloc(sizeof(struct gpioc_pins), M_GPIOC,
+	    M_NOWAIT | M_ZERO);
+	if (pin_link == NULL) {
+		mtx_unlock(&priv->mtx);
+		return (ENOMEM);
+	}
+	priv_link->priv = priv;
+	pin_link->pin = intr_conf;
+	SLIST_INSERT_HEAD(&intr_conf->privs, priv_link, next);
+	SLIST_INSERT_HEAD(&priv->pins, pin_link, next);
+	mtx_unlock(&priv->mtx);
+
+	return (0);
+}
+
+static int
+gpioc_detach_priv_pin(struct gpioc_cdevpriv *priv,
+    struct gpioc_pin_intr *intr_conf)
+{
+	struct gpioc_privs	*priv_link, *priv_link_temp;
+	struct gpioc_pins	*pin_link, *pin_link_temp;
+	unsigned int		consistency_a, consistency_b;
+
+	consistency_a = 0;
+	consistency_b = 0;
+	mtx_assert(&intr_conf->mtx, MA_OWNED);
+	mtx_lock(&priv->mtx);
+	SLIST_FOREACH_SAFE(priv_link, &intr_conf->privs, next, priv_link_temp) {
+		if (priv_link->priv == priv) {
+			SLIST_REMOVE(&intr_conf->privs, priv_link, gpioc_privs,
+			    next);
+			free(priv_link, M_GPIOC);
+			consistency_a++;
+		}
+	}
+	KASSERT(consistency_a <= 1,
+	    ("inconsistent links between pin config and cdevpriv"));
+	SLIST_FOREACH_SAFE(pin_link, &priv->pins, next, pin_link_temp) {
+		if (pin_link->pin == intr_conf) {
+			/*
+			 * If the pin we're removing has events in the priv's
+			 * event fifo, we can't leave dangling pointers from
+			 * those events to the gpioc_pins struct we're about to
+			 * free.  We also can't remove random items and leave
+			 * holes in the events fifo, so just empty it out.
+			 */
+			if (pin_link->eventcount > 0) {
+				priv->evidx_head = priv->evidx_tail = 0;
+			}
+			SLIST_REMOVE(&priv->pins, pin_link, gpioc_pins, next);
+			free(pin_link, M_GPIOC);
+			consistency_b++;
+		}
+	}
+	KASSERT(consistency_a == consistency_b,
+	    ("inconsistent links between pin config and cdevpriv"));
+	mtx_unlock(&priv->mtx);
+
+	return (0);
+}
+
+static bool
+gpioc_intr_reconfig_allowed(struct gpioc_cdevpriv *priv,
+    struct gpioc_pin_intr *intr_conf)
+{
+	struct gpioc_privs	*priv_link;
+
+	mtx_assert(&intr_conf->mtx, MA_OWNED);
+
+	if (SLIST_EMPTY(&intr_conf->privs))
+		return (true);
+
+	SLIST_FOREACH(priv_link, &intr_conf->privs, next) {
+		if (priv_link->priv != priv)
+			return (false);
+	}
+
+	return (true);
+}
+
+
+static uint32_t
+gpioc_get_intr_config(struct gpioc_softc *sc, struct gpioc_cdevpriv *priv,
+    uint32_t pin)
+{
+	struct gpioc_pin_intr	*intr_conf = &sc->sc_pin_intr[pin];
+	struct gpioc_privs	*priv_link;
+	uint32_t		flags;
+
+	flags = intr_conf->pin->flags;
+
+	if (flags == 0)
+		return (0);
+
+	mtx_lock(&intr_conf->mtx);
+	SLIST_FOREACH(priv_link, &intr_conf->privs, next) {
+		if (priv_link->priv == priv) {
+			flags |= GPIO_INTR_ATTACHED;
+			break;
+		}
+	}
+	mtx_unlock(&intr_conf->mtx);
+
+	return (flags);
+}
+
+static int
+gpioc_set_intr_config(struct gpioc_softc *sc, struct gpioc_cdevpriv *priv,
+    uint32_t pin, uint32_t flags)
+{
+	struct gpioc_pin_intr *intr_conf = &sc->sc_pin_intr[pin];
+	int res;
+
+	res = 0;
+	if (intr_conf->pin->flags == 0 && flags == 0) {
+		/* No interrupt configured and none requested: Do nothing. */
+		return (0);
+	}
+	mtx_lock(&intr_conf->mtx);
+	while (intr_conf->config_locked == true)
+		mtx_sleep(&intr_conf->config_locked, &intr_conf->mtx, 0,
+		    "gpicfg", 0);
+	if (intr_conf->pin->flags == 0 && flags != 0) {
+		/*
+		 * No interrupt is configured, but one is requested: Allocate
+		 * and setup interrupt on the according pin.
+		 */
+		res = gpioc_allocate_pin_intr(intr_conf, flags);
+		if (res == 0)
+			res = gpioc_attach_priv_pin(priv, intr_conf);
+		if (res == EEXIST)
+			res = 0;
+	} else if (intr_conf->pin->flags == flags) {
+		/*
+		 * Same interrupt requested as already configured: Attach the
+		 * cdevpriv to the corresponding pin.
+		 */
+		res = gpioc_attach_priv_pin(priv, intr_conf);
+		if (res == EEXIST)
+			res = 0;
+	} else if (intr_conf->pin->flags != 0 && flags == 0) {
+		/*
+		 * Interrupt configured, but none requested: Teardown and
+		 * release the pin when no other cdevpriv is attached. Otherwise
+		 * just detach pin and cdevpriv from each other.
+		 */
+		if (gpioc_intr_reconfig_allowed(priv, intr_conf)) {
+			res = gpioc_release_pin_intr(intr_conf);
+		}
+		if (res == 0)
+			res = gpioc_detach_priv_pin(priv, intr_conf);
+	} else {
+		/*
+		 * Other flag requested than configured: Reconfigure when no
+		 * other cdevpriv is are attached to the pin.
+		 */
+		if (!gpioc_intr_reconfig_allowed(priv, intr_conf))
+			res = EBUSY;
+		else {
+			res = gpioc_release_pin_intr(intr_conf);
+			if (res == 0)
+				res = gpioc_allocate_pin_intr(intr_conf, flags);
+			if (res == 0)
+				res = gpioc_attach_priv_pin(priv, intr_conf);
+			if (res == EEXIST)
+				res = 0;
+		}
+	}
+	mtx_unlock(&intr_conf->mtx);
+
+	return (res);
+}
+
+static void
+gpioc_interrupt_handler(void *arg)
+{
+	struct gpioc_pin_intr *intr_conf;
+	struct gpioc_privs *privs;
+	struct gpioc_softc *sc;
+	sbintime_t evtime;
+	uint32_t pin_state;
+
+	intr_conf = arg;
+	sc = intr_conf->sc;
+
+	/* Capture time and pin state first. */
+	evtime = sbinuptime();
+	if (intr_conf->pin->flags & GPIO_INTR_EDGE_BOTH)
+		GPIO_PIN_GET(sc->sc_pdev, intr_conf->pin->pin, &pin_state);
+	else if (intr_conf->pin->flags & GPIO_INTR_EDGE_RISING)
+		pin_state = true;
+	else
+		pin_state = false;
+
+	mtx_lock(&intr_conf->mtx);
+
+	if (intr_conf->config_locked == true) {
+		ddevice_printf(sc->sc_dev, "Interrupt configuration in "
+		    "progress. Discarding interrupt on pin %d.\n",
+		    intr_conf->pin->pin);
+		mtx_unlock(&intr_conf->mtx);
+		return;
+	}
+
+	if (SLIST_EMPTY(&intr_conf->privs)) {
+		ddevice_printf(sc->sc_dev, "No file descriptor associated with "
+		    "occurred interrupt on pin %d.\n", intr_conf->pin->pin);
+		mtx_unlock(&intr_conf->mtx);
+		return;
+	}
+
+	SLIST_FOREACH(privs, &intr_conf->privs, next) {
+		struct gpioc_cdevpriv *priv = privs->priv;
+		struct gpioc_pins *privpin;
+		struct gpioc_pin_event *event;
+		mtx_lock(&priv->mtx);
+		SLIST_FOREACH(privpin, &priv->pins, next) {
+			if (privpin->pin == intr_conf)
+				break;
+		}
+		if (privpin == NULL) {
+			/* Should be impossible. */
+			ddevice_printf(sc->sc_dev, "Cannot find privpin\n");
+			mtx_unlock(&priv->mtx);
+			continue;
+		}
+
+		if (priv->report_option == GPIO_EVENT_REPORT_DETAIL) {
+			event = next_head_event(priv);
+			/* If head is overtaking tail, advance tail. */
+			if (priv->evidx_head == priv->evidx_tail)
+				next_tail_event(priv);
+		} else {
+			if (privpin->eventcount > 0)
+				event = &priv->events[privpin->firstevent + 1];
+			else {
+				privpin->firstevent = priv->evidx_head;
+				event = next_head_event(priv);
+				event->privpin = privpin;
+				event->event_time = evtime;
+				event->event_pin_state = pin_state;
+				event = next_head_event(priv);
+			}
+			++privpin->eventcount;
+		}
+		event->privpin = privpin;
+		event->event_time = evtime;
+		event->event_pin_state = pin_state;
+		wakeup(priv);
+		selwakeup(&priv->selinfo);
+		KNOTE_LOCKED(&priv->selinfo.si_note, 0);
+		if (priv->async == true && priv->sigio != NULL)
+			pgsigio(&priv->sigio, SIGIO, 0);
+		mtx_unlock(&priv->mtx);
+	}
+
+	mtx_unlock(&intr_conf->mtx);
+}
+
 static int
 gpioc_probe(device_t dev)
 {
@@ -88,6 +575,23 @@ gpioc_attach(device_t dev)
 	sc->sc_dev = dev;
 	sc->sc_pdev = device_get_parent(dev);
 	sc->sc_unit = device_get_unit(dev);
+
+	err = GPIO_PIN_MAX(sc->sc_pdev, &sc->sc_npins);
+	sc->sc_npins++; /* Number of pins is one more than max pin number. */
+	if (err != 0)
+		return (err);
+	sc->sc_pin_intr = malloc(sizeof(struct gpioc_pin_intr) * sc->sc_npins,
+	    M_GPIOC, M_WAITOK | M_ZERO);
+	for (int i = 0; i <= sc->sc_npins; i++) {
+		sc->sc_pin_intr[i].pin = malloc(sizeof(struct gpiobus_pin),
+		    M_GPIOC, M_WAITOK | M_ZERO);
+		sc->sc_pin_intr[i].sc = sc;
+		sc->sc_pin_intr[i].pin->pin = i;
+		sc->sc_pin_intr[i].pin->dev = sc->sc_pdev;
+		mtx_init(&sc->sc_pin_intr[i].mtx, "gpioc pin", NULL, MTX_DEF);
+		SLIST_INIT(&sc->sc_pin_intr[i].privs);
+	}
+
 	make_dev_args_init(&devargs);
 	devargs.mda_devsw = &gpioc_cdevsw;
 	devargs.mda_uid = UID_ROOT;
@@ -96,7 +600,7 @@ gpioc_attach(device_t dev)
 	devargs.mda_si_drv1 = sc;
 	err = make_dev_s(&devargs, &sc->sc_ctl_dev, "gpioc%d", sc->sc_unit);
 	if (err != 0) {
-		printf("Failed to create gpioc%d", sc->sc_unit);
+		device_printf(dev, "Failed to create gpioc%d", sc->sc_unit);
 		return (ENXIO);
 	}
 
@@ -112,12 +616,160 @@ gpioc_detach(device_t dev)
 	if (sc->sc_ctl_dev)
 		destroy_dev(sc->sc_ctl_dev);
 
+	for (int i = 0; i <= sc->sc_npins; i++) {
+		mtx_destroy(&sc->sc_pin_intr[i].mtx);
+		free(&sc->sc_pin_intr[i].pin, M_GPIOC);
+	}
+	free(sc->sc_pin_intr, M_GPIOC);
+
 	if ((err = bus_generic_detach(dev)) != 0)
 		return (err);
 
 	return (0);
 }
 
+static void
+gpioc_cdevpriv_dtor(void *data)
+{
+	struct gpioc_cdevpriv	*priv;
+	struct gpioc_privs	*priv_link, *priv_link_temp;
+	struct gpioc_pins	*pin_link, *pin_link_temp;
+	unsigned int		consistency;
+
+	priv = data;
+
+	SLIST_FOREACH_SAFE(pin_link, &priv->pins, next, pin_link_temp) {
+		consistency = 0;
+		mtx_lock(&pin_link->pin->mtx);
+		while (pin_link->pin->config_locked == true)
+			mtx_sleep(&pin_link->pin->config_locked,
+			    &pin_link->pin->mtx, 0, "gpicfg", 0);
+		SLIST_FOREACH_SAFE(priv_link, &pin_link->pin->privs, next,
+		    priv_link_temp) {
+			if (priv_link->priv == priv) {
+				SLIST_REMOVE(&pin_link->pin->privs, priv_link,
+				    gpioc_privs, next);
+				free(priv_link, M_GPIOC);
+				consistency++;
+			}
+		}
+		KASSERT(consistency == 1,
+		    ("inconsistent links between pin config and cdevpriv"));
+		if (gpioc_intr_reconfig_allowed(priv, pin_link->pin)) {
+			gpioc_release_pin_intr(pin_link->pin);
+		}
+		mtx_unlock(&pin_link->pin->mtx);
+		SLIST_REMOVE(&priv->pins, pin_link, gpioc_pins, next);
+		free(pin_link, M_GPIOC);
+	}
+
+	wakeup(&priv);
+	knlist_clear(&priv->selinfo.si_note, 0);
+	seldrain(&priv->selinfo);
+	knlist_destroy(&priv->selinfo.si_note);
+	funsetown(&priv->sigio);
+
+	mtx_destroy(&priv->mtx);
+	free(priv->events, M_GPIOC);
+	free(data, M_GPIOC);
+}
+
+static int
+gpioc_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
+{
+	struct gpioc_cdevpriv *priv;
+	int err;
+
+	priv = malloc(sizeof(*priv), M_GPIOC, M_WAITOK | M_ZERO);
+	priv->sc = dev->si_drv1;
+	priv->report_option = GPIO_EVENT_REPORT_DETAIL;
+	err = devfs_set_cdevpriv(priv, gpioc_cdevpriv_dtor);
+	if (err != 0) {
+		gpioc_cdevpriv_dtor(priv);
+		return (err);
+	}
+	mtx_init(&priv->mtx, "gpioc priv", NULL, MTX_DEF);
+	knlist_init_mtx(&priv->selinfo.si_note, &priv->mtx);
+
+	/*
+	 * Allocate a circular buffer for events.  The scheme we use for summary
+	 * reporting assumes there will always be a pair of events available to
+	 * record the first/last events on any pin, so we allocate 2 * npins.
+	 * Even though we actually default to detailed event reporting, 2 *
+	 * npins isn't a horrible fifo size for that either.
+	 */
+	priv->numevents = priv->sc->sc_npins * 2;
+	priv->events = malloc(priv->numevents * sizeof(struct gpio_event_detail),
+	    M_GPIOC, M_WAITOK | M_ZERO);
+
+	return (0);
+}
+
+static int
+gpioc_read(struct cdev *dev, struct uio *uio, int ioflag)
+{
+	struct gpioc_cdevpriv *priv;
+	struct gpioc_pin_event *event;
+	union {
+		struct gpio_event_summary sum;
+		struct gpio_event_detail  evt;
+		uint8_t 		  data[1];
+	} recbuf;
+	size_t recsize;
+	int err;
+
+	if ((err = devfs_get_cdevpriv((void **)&priv)) != 0)
+		return (err);
+
+	if (priv->report_option == GPIO_EVENT_REPORT_SUMMARY)
+		recsize = sizeof(struct gpio_event_summary);
+	else
+		recsize = sizeof(struct gpio_event_detail);
+
+	if (uio->uio_resid < recsize)
+		return (EINVAL);
+
+	mtx_lock(&priv->mtx);
+	while (priv->evidx_head == priv->evidx_tail) {
+		if (SLIST_EMPTY(&priv->pins)) {
+			err = ENXIO;
+			break;
+		} else if (ioflag & O_NONBLOCK) {
+			err = EWOULDBLOCK;
+			break;
+		} else {
+			err = mtx_sleep(priv, &priv->mtx, PCATCH, "gpintr", 0);
+			if (err != 0)
+				break;
+		}
+	}
+
+	while (err == 0 && uio->uio_resid >= recsize &&
+           priv->evidx_tail != priv->evidx_head) {
+		event = next_tail_event(priv);
+		if (priv->report_option == GPIO_EVENT_REPORT_SUMMARY) {
+			recbuf.sum.gp_first_time = event->event_time;
+			recbuf.sum.gp_pin = event->privpin->pin->pin->pin;
+			recbuf.sum.gp_count = event->privpin->eventcount;
+			recbuf.sum.gp_first_state = event->event_pin_state;
+			event = next_tail_event(priv);
+			recbuf.sum.gp_last_time = event->event_time;
+			recbuf.sum.gp_last_state = event->event_pin_state;
+			event->privpin->eventcount = 0;
+			event->privpin->firstevent = 0;
+		} else {
+			recbuf.evt.gp_time = event->event_time;
+			recbuf.evt.gp_pin = event->privpin->pin->pin->pin;
+			recbuf.evt.gp_pinstate = event->event_pin_state;
+		}
+		mtx_unlock(&priv->mtx);
+		err = uiomove(recbuf.data, recsize, uio);
+		mtx_lock(&priv->mtx);
+	}
+	mtx_unlock(&priv->mtx);
+	return (err);
+}
+
 static int 
 gpioc_ioctl(struct cdev *cdev, u_long cmd, caddr_t arg, int fflag, 
     struct thread *td)
@@ -125,88 +777,270 @@ gpioc_ioctl(struct cdev *cdev, u_long cmd, caddr_t arg, int fflag,
 	device_t bus;
 	int max_pin, res;
 	struct gpioc_softc *sc = cdev->si_drv1;
+	struct gpioc_cdevpriv *priv;
 	struct gpio_pin pin;
 	struct gpio_req req;
 	struct gpio_access_32 *a32;
 	struct gpio_config_32 *c32;
-	uint32_t caps;
+	struct gpio_event_config *evcfg;
+	uint32_t caps, intrflags;
 
 	bus = GPIO_GET_BUS(sc->sc_pdev);
 	if (bus == NULL)
 		return (EINVAL);
 	switch (cmd) {
-		case GPIOMAXPIN:
-			max_pin = -1;
-			res = GPIO_PIN_MAX(sc->sc_pdev, &max_pin);
-			bcopy(&max_pin, arg, sizeof(max_pin));
+	case GPIOMAXPIN:
+		max_pin = -1;
+		res = GPIO_PIN_MAX(sc->sc_pdev, &max_pin);
+		bcopy(&max_pin, arg, sizeof(max_pin));
+		break;
+	case GPIOGETCONFIG:
+		bcopy(arg, &pin, sizeof(pin));
+		dprintf("get config pin %d\n", pin.gp_pin);
+		res = GPIO_PIN_GETFLAGS(sc->sc_pdev, pin.gp_pin,
+		    &pin.gp_flags);
+		/* Fail early */
+		if (res)
 			break;
-		case GPIOGETCONFIG:
-			bcopy(arg, &pin, sizeof(pin));
-			dprintf("get config pin %d\n", pin.gp_pin);
-			res = GPIO_PIN_GETFLAGS(sc->sc_pdev, pin.gp_pin,
-			    &pin.gp_flags);
-			/* Fail early */
-			if (res)
-				break;
-			GPIO_PIN_GETCAPS(sc->sc_pdev, pin.gp_pin, &pin.gp_caps);
-			GPIOBUS_PIN_GETNAME(bus, pin.gp_pin, pin.gp_name);
-			bcopy(&pin, arg, sizeof(pin));
+		res = devfs_get_cdevpriv((void **)&priv);
+		if (res)
 			break;
-		case GPIOSETCONFIG:
-			bcopy(arg, &pin, sizeof(pin));
-			dprintf("set config pin %d\n", pin.gp_pin);
-			res = GPIO_PIN_GETCAPS(sc->sc_pdev, pin.gp_pin, &caps);
-			if (res == 0)
-				res = gpio_check_flags(caps, pin.gp_flags);
-			if (res == 0)
-				res = GPIO_PIN_SETFLAGS(sc->sc_pdev, pin.gp_pin,
-				    pin.gp_flags);
+		pin.gp_flags |= gpioc_get_intr_config(sc, priv,
+		    pin.gp_pin);
+		GPIO_PIN_GETCAPS(sc->sc_pdev, pin.gp_pin, &pin.gp_caps);
+		GPIOBUS_PIN_GETNAME(bus, pin.gp_pin, pin.gp_name);
+		bcopy(&pin, arg, sizeof(pin));
+		break;
+	case GPIOSETCONFIG:
+		bcopy(arg, &pin, sizeof(pin));
+		dprintf("set config pin %d\n", pin.gp_pin);
+		res = devfs_get_cdevpriv((void **)&priv);
+		if (res != 0)
 			break;
-		case GPIOGET:
-			bcopy(arg, &req, sizeof(req));
-			res = GPIO_PIN_GET(sc->sc_pdev, req.gp_pin,
-			    &req.gp_value);
-			dprintf("read pin %d -> %d\n", 
-			    req.gp_pin, req.gp_value);
-			bcopy(&req, arg, sizeof(req));
+		res = GPIO_PIN_GETCAPS(sc->sc_pdev, pin.gp_pin, &caps);
+		if (res != 0)
 			break;
-		case GPIOSET:
-			bcopy(arg, &req, sizeof(req));
-			res = GPIO_PIN_SET(sc->sc_pdev, req.gp_pin, 
-			    req.gp_value);
-			dprintf("write pin %d -> %d\n", 
-			    req.gp_pin, req.gp_value);
+		res = gpio_check_flags(caps, pin.gp_flags);
+		if (res != 0)
 			break;
-		case GPIOTOGGLE:
-			bcopy(arg, &req, sizeof(req));
-			dprintf("toggle pin %d\n", 
-			    req.gp_pin);
-			res = GPIO_PIN_TOGGLE(sc->sc_pdev, req.gp_pin);
+		intrflags = pin.gp_flags & GPIO_INTR_MASK;
+		/*
+		 * We can do only edge interrupts, and only if the
+		 * hardware supports that interrupt type on that pin.
+		 */
+		switch (intrflags) {
+		case GPIO_INTR_NONE:
 			break;
-		case GPIOSETNAME:
-			bcopy(arg, &pin, sizeof(pin));
-			dprintf("set name on pin %d\n", pin.gp_pin);
-			res = GPIOBUS_PIN_SETNAME(bus, pin.gp_pin,
-			    pin.gp_name);
+		case GPIO_INTR_EDGE_RISING:
+		case GPIO_INTR_EDGE_FALLING:
+		case GPIO_INTR_EDGE_BOTH:
+			if ((intrflags & caps) == 0)
+				res = EOPNOTSUPP;
 			break;
-		case GPIOACCESS32:
-			a32 = (struct gpio_access_32 *)arg;
-			res = GPIO_PIN_ACCESS_32(sc->sc_pdev, a32->first_pin,
-			    a32->clear_pins, a32->change_pins, &a32->orig_pins);
+		default:
+			res = EINVAL;
 			break;
-		case GPIOCONFIG32:
-			c32 = (struct gpio_config_32 *)arg;
-			res = GPIO_PIN_CONFIG_32(sc->sc_pdev, c32->first_pin,
-			    c32->num_pins, c32->pin_flags);
+		}
+		if (res != 0)
 			break;
-		default:
-			return (ENOTTY);
+		res = GPIO_PIN_SETFLAGS(sc->sc_pdev, pin.gp_pin,
+		    (pin.gp_flags & ~GPIO_INTR_MASK));
+		if (res != 0)
+			break;
+		res = gpioc_set_intr_config(sc, priv, pin.gp_pin,
+		    intrflags);
+		break;
+	case GPIOGET:
+		bcopy(arg, &req, sizeof(req));
+		res = GPIO_PIN_GET(sc->sc_pdev, req.gp_pin,
+		    &req.gp_value);
+		dprintf("read pin %d -> %d\n", 
+		    req.gp_pin, req.gp_value);
+		bcopy(&req, arg, sizeof(req));
+		break;
+	case GPIOSET:
+		bcopy(arg, &req, sizeof(req));
+		res = GPIO_PIN_SET(sc->sc_pdev, req.gp_pin, 
+		    req.gp_value);
+		dprintf("write pin %d -> %d\n", 
+		    req.gp_pin, req.gp_value);
+		break;
+	case GPIOTOGGLE:
+		bcopy(arg, &req, sizeof(req));
+		dprintf("toggle pin %d\n", 
+		    req.gp_pin);
+		res = GPIO_PIN_TOGGLE(sc->sc_pdev, req.gp_pin);
+		break;
+	case GPIOSETNAME:
+		bcopy(arg, &pin, sizeof(pin));
+		dprintf("set name on pin %d\n", pin.gp_pin);
+		res = GPIOBUS_PIN_SETNAME(bus, pin.gp_pin,
+		    pin.gp_name);
+		break;
+	case GPIOACCESS32:
+		a32 = (struct gpio_access_32 *)arg;
+		res = GPIO_PIN_ACCESS_32(sc->sc_pdev, a32->first_pin,
+		    a32->clear_pins, a32->change_pins, &a32->orig_pins);
+		break;
+	case GPIOCONFIG32:
+		c32 = (struct gpio_config_32 *)arg;
+		res = GPIO_PIN_CONFIG_32(sc->sc_pdev, c32->first_pin,
+		    c32->num_pins, c32->pin_flags);
+		break;
+	case GPIOCONFIGEVENTS:
+		evcfg = (struct gpio_event_config *)arg;
+		res = devfs_get_cdevpriv((void **)&priv);
+		if (res != 0)
+			break;
+		/* If any pins have been configured, changes aren't allowed. */
+		if (!SLIST_EMPTY(&priv->pins)) {
+			res = EINVAL;
+			break;
+		}
+		if (evcfg->gp_report_type != GPIO_EVENT_REPORT_DETAIL &&
+		    evcfg->gp_report_type != GPIO_EVENT_REPORT_SUMMARY) {
+			res = EINVAL;
 			break;
+		}
+		priv->report_option = evcfg->gp_report_type;
+		/* Reallocate the events buffer if the user wants it bigger. */
+		if (priv->report_option == GPIO_EVENT_REPORT_DETAIL &&
+		    priv->numevents < evcfg->gp_fifo_size) {
+			free(priv->events, M_GPIOC);
+			priv->numevents = evcfg->gp_fifo_size;
+			priv->events = malloc(priv->numevents *
+			    sizeof(struct gpio_event_detail), M_GPIOC,
+			    M_WAITOK | M_ZERO);
+			priv->evidx_head = priv->evidx_tail = 0;
+		}
+		break;
+	case FIONBIO:
+		/*
+		 * This dummy handler is necessary to prevent fcntl()
+		 * from failing. The actual handling of non-blocking IO
+		 * is done using the O_NONBLOCK ioflag passed to the
+		 * read() syscall.
+		 */
+		res = 0;
+		break;
+	case FIOASYNC:
+		res = devfs_get_cdevpriv((void **)&priv);
+		if (res == 0) {
+			if (*(int *)arg == FASYNC)
+				priv->async = true;
+			else
+				priv->async = false;
+		}
+		break;
+	case FIOGETOWN:
+		res = devfs_get_cdevpriv((void **)&priv);
+		if (res == 0)
+			*(int *)arg = fgetown(&priv->sigio);
+		break;
+	case FIOSETOWN:
+		res = devfs_get_cdevpriv((void **)&priv);
+		if (res == 0)
+			res = fsetown(*(int *)arg, &priv->sigio);
+		break;
+	default:
+		return (ENOTTY);
+		break;
 	}
 
 	return (res);
 }
 
+static int
+gpioc_poll(struct cdev *dev, int events, struct thread *td)
+{
+	struct gpioc_cdevpriv *priv;
+	int err;
+	int revents;
+
+	revents = 0;
+
+	err = devfs_get_cdevpriv((void **)&priv);
+	if (err != 0) {
+		revents = POLLERR;
+		return (revents);
+	}
+
+	if (SLIST_EMPTY(&priv->pins)) {
+		revents = POLLHUP;
+		return (revents);
+	}
+
+	if (events & (POLLIN | POLLRDNORM)) {
+		if (priv->evidx_head != priv->evidx_tail)
+			revents |= events & (POLLIN | POLLRDNORM);
+		else
+			selrecord(td, &priv->selinfo);
+	}
+
+	return (revents);
+}
+
+static int
+gpioc_kqfilter(struct cdev *dev, struct knote *kn)
+{
+	struct gpioc_cdevpriv *priv;
+	struct knlist *knlist;
+	int err;
+
+	err = devfs_get_cdevpriv((void **)&priv);
+	if (err != 0)
+		return err;
+
+	if (SLIST_EMPTY(&priv->pins))
+		return (ENXIO);
+
+	switch(kn->kn_filter) {
+	case EVFILT_READ:
+		kn->kn_fop = &gpioc_read_filterops;
+		kn->kn_hook = (void *)priv;
+		break;
+	default:
+		return (EOPNOTSUPP);
+	}
+
+	knlist = &priv->selinfo.si_note;
+	knlist_add(knlist, kn, 0);
+
+	return (0);
+}
+
+static int
+gpioc_kqread(struct knote *kn, long hint)
+{
+	struct gpioc_cdevpriv *priv = kn->kn_hook;
+	size_t recsize;
+
+
+	if (SLIST_EMPTY(&priv->pins)) {
+		kn->kn_flags |= EV_EOF;
+		return (1);
+	} else {
+		if (priv->evidx_head != priv->evidx_tail) {
+			if (priv->report_option == GPIO_EVENT_REPORT_SUMMARY)
+				recsize = sizeof(struct gpio_event_summary);
+			else
+				recsize = sizeof(struct gpio_event_detail);
+			kn->kn_data = recsize * number_of_events(priv);
+			return (1);
+		}
+	}
+	return (0);
+}
+
+static void
+gpioc_kqdetach(struct knote *kn)
+{
+	struct gpioc_cdevpriv *priv = kn->kn_hook;
+	struct knlist *knlist = &priv->selinfo.si_note;
+
+	knlist_remove(knlist, kn, 0);
+}
+
 static device_method_t gpioc_methods[] = {
 	/* Device interface */
 	DEVMETHOD(device_probe,		gpioc_probe),