--- zzzz-none-000/linux-4.4.271/drivers/gpio/gpiolib.c	2021-06-03 06:22:09.000000000 +0000
+++ dakota-7530ac-750/linux-4.4.271/drivers/gpio/gpiolib.c	2023-01-11 09:25:41.000000000 +0000
@@ -16,6 +16,16 @@
 #include <linux/gpio/driver.h>
 #include <linux/gpio/machine.h>
 #include <linux/pinctrl/consumer.h>
+#include <linux/cdev.h>
+#include <linux/fs.h>
+#include <linux/uaccess.h>
+#include <linux/compat.h>
+#include <linux/anon_inodes.h>
+#include <linux/file.h>
+#include <linux/kfifo.h>
+#include <linux/poll.h>
+#include <linux/timekeeping.h>
+#include <uapi/linux/gpio.h>
 
 #include "gpiolib.h"
 
@@ -42,6 +52,14 @@
 #define	extra_checks	0
 #endif
 
+/* Device and char device-related information */
+static DEFINE_IDA(gpio_ida);
+static dev_t gpio_devt;
+#define GPIO_DEV_MAX 256 /* 256 GPIO chip devices supported */
+static struct bus_type gpio_bus_type = {
+	.name = "gpio",
+};
+
 /* gpio_lock prevents conflicts during gpio_desc[] table updates.
  * While any GPIO is requested, its gpio_chip is not removable;
  * each GPIO's "requested" flag serves as a lock and refcount.
@@ -50,12 +68,14 @@
 
 static DEFINE_MUTEX(gpio_lookup_lock);
 static LIST_HEAD(gpio_lookup_list);
-LIST_HEAD(gpio_chips);
-
+LIST_HEAD(gpio_devices);
 
 static void gpiochip_free_hogs(struct gpio_chip *chip);
 static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip);
+static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip);
+static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip);
 
+static bool gpiolib_initialized;
 
 static inline void desc_set_label(struct gpio_desc *d, const char *label)
 {
@@ -67,15 +87,16 @@
  */
 struct gpio_desc *gpio_to_desc(unsigned gpio)
 {
-	struct gpio_chip *chip;
+	struct gpio_device *gdev;
 	unsigned long flags;
 
 	spin_lock_irqsave(&gpio_lock, flags);
 
-	list_for_each_entry(chip, &gpio_chips, list) {
-		if (chip->base <= gpio && chip->base + chip->ngpio > gpio) {
+	list_for_each_entry(gdev, &gpio_devices, list) {
+		if (gdev->base <= gpio &&
+		    gdev->base + gdev->ngpio > gpio) {
 			spin_unlock_irqrestore(&gpio_lock, flags);
-			return &chip->desc[gpio - chip->base];
+			return &gdev->descs[gpio - gdev->base];
 		}
 	}
 
@@ -94,11 +115,14 @@
 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip,
 				    u16 hwnum)
 {
-	if (hwnum >= chip->ngpio)
+	struct gpio_device *gdev = chip->gpiodev;
+
+	if (hwnum >= gdev->ngpio)
 		return ERR_PTR(-EINVAL);
 
-	return &chip->desc[hwnum];
+	return &gdev->descs[hwnum];
 }
+EXPORT_SYMBOL_GPL(gpiochip_get_desc);
 
 /**
  * Convert a GPIO descriptor to the integer namespace.
@@ -107,7 +131,7 @@
  */
 int desc_to_gpio(const struct gpio_desc *desc)
 {
-	return desc->chip->base + (desc - &desc->chip->desc[0]);
+	return desc->gdev->base + (desc - &desc->gdev->descs[0]);
 }
 EXPORT_SYMBOL_GPL(desc_to_gpio);
 
@@ -118,23 +142,25 @@
  */
 struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
 {
-	return desc ? desc->chip : NULL;
+	if (!desc || !desc->gdev || !desc->gdev->chip)
+		return NULL;
+	return desc->gdev->chip;
 }
 EXPORT_SYMBOL_GPL(gpiod_to_chip);
 
 /* dynamic allocation of GPIOs, e.g. on a hotplugged device */
 static int gpiochip_find_base(int ngpio)
 {
-	struct gpio_chip *chip;
+	struct gpio_device *gdev;
 	int base = ARCH_NR_GPIOS - ngpio;
 
-	list_for_each_entry_reverse(chip, &gpio_chips, list) {
+	list_for_each_entry_reverse(gdev, &gpio_devices, list) {
 		/* found a free space? */
-		if (chip->base + chip->ngpio <= base)
+		if (gdev->base + gdev->ngpio <= base)
 			break;
 		else
 			/* nope, check the space right before the chip */
-			base = chip->base - ngpio;
+			base = gdev->base - ngpio;
 	}
 
 	if (gpio_is_valid(base)) {
@@ -190,39 +216,50 @@
 
 /*
  * Add a new chip to the global chips list, keeping the list of chips sorted
- * by base order.
+ * by range(means [base, base + ngpio - 1]) order.
  *
  * Return -EBUSY if the new chip overlaps with some other chip's integer
  * space.
  */
-static int gpiochip_add_to_list(struct gpio_chip *chip)
+static int gpiodev_add_to_list(struct gpio_device *gdev)
 {
-	struct list_head *pos;
-	struct gpio_chip *_chip;
-	int err = 0;
+	struct gpio_device *prev, *next;
 
-	/* find where to insert our chip */
-	list_for_each(pos, &gpio_chips) {
-		_chip = list_entry(pos, struct gpio_chip, list);
-		/* shall we insert before _chip? */
-		if (_chip->base >= chip->base + chip->ngpio)
-			break;
+	if (list_empty(&gpio_devices)) {
+		/* initial entry in list */
+		list_add_tail(&gdev->list, &gpio_devices);
+		return 0;
 	}
 
-	/* are we stepping on the chip right before? */
-	if (pos != &gpio_chips && pos->prev != &gpio_chips) {
-		_chip = list_entry(pos->prev, struct gpio_chip, list);
-		if (_chip->base + _chip->ngpio > chip->base) {
-			dev_err(chip->dev,
-			       "GPIO integer space overlap, cannot add chip\n");
-			err = -EBUSY;
-		}
+	next = list_entry(gpio_devices.next, struct gpio_device, list);
+	if (gdev->base + gdev->ngpio <= next->base) {
+		/* add before first entry */
+		list_add(&gdev->list, &gpio_devices);
+		return 0;
 	}
 
-	if (!err)
-		list_add_tail(&chip->list, pos);
+	prev = list_entry(gpio_devices.prev, struct gpio_device, list);
+	if (prev->base + prev->ngpio <= gdev->base) {
+		/* add behind last entry */
+		list_add_tail(&gdev->list, &gpio_devices);
+		return 0;
+	}
+
+	list_for_each_entry_safe(prev, next, &gpio_devices, list) {
+		/* at the end of the list */
+		if (&next->list == &gpio_devices)
+			break;
 
-	return err;
+		/* add between prev and next */
+		if (prev->base + prev->ngpio <= gdev->base
+				&& gdev->base + gdev->ngpio <= next->base) {
+			list_add(&gdev->list, &prev->list);
+			return 0;
+		}
+	}
+
+	dev_err(&gdev->dev, "GPIO integer space overlap, cannot add chip\n");
+	return -EBUSY;
 }
 
 /**
@@ -230,23 +267,23 @@
  */
 static struct gpio_desc *gpio_name_to_desc(const char * const name)
 {
-	struct gpio_chip *chip;
+	struct gpio_device *gdev;
 	unsigned long flags;
 
 	spin_lock_irqsave(&gpio_lock, flags);
 
-	list_for_each_entry(chip, &gpio_chips, list) {
+	list_for_each_entry(gdev, &gpio_devices, list) {
 		int i;
 
-		for (i = 0; i != chip->ngpio; ++i) {
-			struct gpio_desc *gpio = &chip->desc[i];
+		for (i = 0; i != gdev->ngpio; ++i) {
+			struct gpio_desc *desc = &gdev->descs[i];
 
-			if (!gpio->name || !name)
+			if (!desc->name || !name)
 				continue;
 
-			if (!strcmp(gpio->name, name)) {
+			if (!strcmp(desc->name, name)) {
 				spin_unlock_irqrestore(&gpio_lock, flags);
-				return gpio;
+				return desc;
 			}
 		}
 	}
@@ -264,6 +301,7 @@
  */
 static int gpiochip_set_desc_names(struct gpio_chip *gc)
 {
+	struct gpio_device *gdev = gc->gpiodev;
 	int i;
 
 	if (!gc->names)
@@ -275,20 +313,784 @@
 
 		gpio = gpio_name_to_desc(gc->names[i]);
 		if (gpio)
-			dev_warn(gc->dev, "Detected name collision for "
-				 "GPIO name '%s'\n",
+			dev_warn(&gdev->dev,
+				 "Detected name collision for GPIO name '%s'\n",
 				 gc->names[i]);
 	}
 
 	/* Then add all names to the GPIO descriptors */
 	for (i = 0; i != gc->ngpio; ++i)
-		gc->desc[i].name = gc->names[i];
+		gdev->descs[i].name = gc->names[i];
+
+	return 0;
+}
+
+/*
+ * GPIO line handle management
+ */
+
+/**
+ * struct linehandle_state - contains the state of a userspace handle
+ * @gdev: the GPIO device the handle pertains to
+ * @label: consumer label used to tag descriptors
+ * @descs: the GPIO descriptors held by this handle
+ * @numdescs: the number of descriptors held in the descs array
+ */
+struct linehandle_state {
+	struct gpio_device *gdev;
+	const char *label;
+	struct gpio_desc *descs[GPIOHANDLES_MAX];
+	u32 numdescs;
+};
+
+#define GPIOHANDLE_REQUEST_VALID_FLAGS \
+	(GPIOHANDLE_REQUEST_INPUT | \
+	GPIOHANDLE_REQUEST_OUTPUT | \
+	GPIOHANDLE_REQUEST_ACTIVE_LOW | \
+	GPIOHANDLE_REQUEST_OPEN_DRAIN | \
+	GPIOHANDLE_REQUEST_OPEN_SOURCE)
+
+static long linehandle_ioctl(struct file *filep, unsigned int cmd,
+			     unsigned long arg)
+{
+	struct linehandle_state *lh = filep->private_data;
+	void __user *ip = (void __user *)arg;
+	struct gpiohandle_data ghd;
+	int i;
+
+	if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) {
+		int val;
+
+		memset(&ghd, 0, sizeof(ghd));
+
+		/* TODO: check if descriptors are really input */
+		for (i = 0; i < lh->numdescs; i++) {
+			val = gpiod_get_value_cansleep(lh->descs[i]);
+			if (val < 0)
+				return val;
+			ghd.values[i] = val;
+		}
+
+		if (copy_to_user(ip, &ghd, sizeof(ghd)))
+			return -EFAULT;
+
+		return 0;
+	} else if (cmd == GPIOHANDLE_SET_LINE_VALUES_IOCTL) {
+		int vals[GPIOHANDLES_MAX];
+
+		/* TODO: check if descriptors are really output */
+		if (copy_from_user(&ghd, ip, sizeof(ghd)))
+			return -EFAULT;
+
+		/* Clamp all values to [0,1] */
+		for (i = 0; i < lh->numdescs; i++)
+			vals[i] = !!ghd.values[i];
+
+		/* Reuse the array setting function */
+		gpiod_set_array_value_complex(false,
+					      true,
+					      lh->numdescs,
+					      lh->descs,
+					      vals);
+		return 0;
+	}
+	return -EINVAL;
+}
+
+#ifdef CONFIG_COMPAT
+static long linehandle_ioctl_compat(struct file *filep, unsigned int cmd,
+			     unsigned long arg)
+{
+	return linehandle_ioctl(filep, cmd, (unsigned long)compat_ptr(arg));
+}
+#endif
+
+static int linehandle_release(struct inode *inode, struct file *filep)
+{
+	struct linehandle_state *lh = filep->private_data;
+	struct gpio_device *gdev = lh->gdev;
+	int i;
+
+	for (i = 0; i < lh->numdescs; i++)
+		gpiod_free(lh->descs[i]);
+	kfree(lh->label);
+	kfree(lh);
+	put_device(&gdev->dev);
+	return 0;
+}
+
+static const struct file_operations linehandle_fileops = {
+	.release = linehandle_release,
+	.owner = THIS_MODULE,
+	.llseek = noop_llseek,
+	.unlocked_ioctl = linehandle_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl = linehandle_ioctl_compat,
+#endif
+};
+
+static int linehandle_create(struct gpio_device *gdev, void __user *ip)
+{
+	struct gpiohandle_request handlereq;
+	struct linehandle_state *lh;
+	struct file *file;
+	int fd, i, ret;
+
+	if (copy_from_user(&handlereq, ip, sizeof(handlereq)))
+		return -EFAULT;
+	if ((handlereq.lines == 0) || (handlereq.lines > GPIOHANDLES_MAX))
+		return -EINVAL;
+
+	lh = kzalloc(sizeof(*lh), GFP_KERNEL);
+	if (!lh)
+		return -ENOMEM;
+	lh->gdev = gdev;
+	get_device(&gdev->dev);
+
+	/* Make sure this is terminated */
+	handlereq.consumer_label[sizeof(handlereq.consumer_label)-1] = '\0';
+	if (strlen(handlereq.consumer_label)) {
+		lh->label = kstrdup(handlereq.consumer_label,
+				    GFP_KERNEL);
+		if (!lh->label) {
+			ret = -ENOMEM;
+			goto out_free_lh;
+		}
+	}
+
+	/* Request each GPIO */
+	for (i = 0; i < handlereq.lines; i++) {
+		u32 offset = handlereq.lineoffsets[i];
+		u32 lflags = handlereq.flags;
+		struct gpio_desc *desc;
+
+		if (offset >= gdev->ngpio) {
+			ret = -EINVAL;
+			goto out_free_descs;
+		}
+
+		/* Return an error if a unknown flag is set */
+		if (lflags & ~GPIOHANDLE_REQUEST_VALID_FLAGS) {
+			ret = -EINVAL;
+			goto out_free_descs;
+		}
+
+		desc = &gdev->descs[offset];
+		ret = gpiod_request(desc, lh->label);
+		if (ret)
+			goto out_free_descs;
+		lh->descs[i] = desc;
+
+		if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW)
+			set_bit(FLAG_ACTIVE_LOW, &desc->flags);
+		if (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN)
+			set_bit(FLAG_OPEN_DRAIN, &desc->flags);
+		if (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)
+			set_bit(FLAG_OPEN_SOURCE, &desc->flags);
+
+		/*
+		 * Lines have to be requested explicitly for input
+		 * or output, else the line will be treated "as is".
+		 */
+		if (lflags & GPIOHANDLE_REQUEST_OUTPUT) {
+			int val = !!handlereq.default_values[i];
+
+			ret = gpiod_direction_output(desc, val);
+			if (ret)
+				goto out_free_descs;
+		} else if (lflags & GPIOHANDLE_REQUEST_INPUT) {
+			ret = gpiod_direction_input(desc);
+			if (ret)
+				goto out_free_descs;
+		}
+		dev_dbg(&gdev->dev, "registered chardev handle for line %d\n",
+			offset);
+	}
+	/* Let i point at the last handle */
+	i--;
+	lh->numdescs = handlereq.lines;
+
+	fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);
+	if (fd < 0) {
+		ret = fd;
+		goto out_free_descs;
+	}
+
+	file = anon_inode_getfile("gpio-linehandle",
+				  &linehandle_fileops,
+				  lh,
+				  O_RDONLY | O_CLOEXEC);
+	if (IS_ERR(file)) {
+		ret = PTR_ERR(file);
+		goto out_put_unused_fd;
+	}
+
+	handlereq.fd = fd;
+	if (copy_to_user(ip, &handlereq, sizeof(handlereq))) {
+		/*
+		 * fput() will trigger the release() callback, so do not go onto
+		 * the regular error cleanup path here.
+		 */
+		fput(file);
+		put_unused_fd(fd);
+		return -EFAULT;
+	}
+
+	fd_install(fd, file);
+
+	dev_dbg(&gdev->dev, "registered chardev handle for %d lines\n",
+		lh->numdescs);
+
+	return 0;
+
+out_put_unused_fd:
+	put_unused_fd(fd);
+out_free_descs:
+	for (; i >= 0; i--)
+		gpiod_free(lh->descs[i]);
+	kfree(lh->label);
+out_free_lh:
+	kfree(lh);
+	put_device(&gdev->dev);
+	return ret;
+}
+
+/*
+ * GPIO line event management
+ */
+
+/**
+ * struct lineevent_state - contains the state of a userspace event
+ * @gdev: the GPIO device the event pertains to
+ * @label: consumer label used to tag descriptors
+ * @desc: the GPIO descriptor held by this event
+ * @eflags: the event flags this line was requested with
+ * @irq: the interrupt that trigger in response to events on this GPIO
+ * @wait: wait queue that handles blocking reads of events
+ * @events: KFIFO for the GPIO events
+ * @read_lock: mutex lock to protect reads from colliding with adding
+ * new events to the FIFO
+ */
+struct lineevent_state {
+	struct gpio_device *gdev;
+	const char *label;
+	struct gpio_desc *desc;
+	u32 eflags;
+	int irq;
+	wait_queue_head_t wait;
+	DECLARE_KFIFO(events, struct gpioevent_data, 16);
+	struct mutex read_lock;
+};
+
+#define GPIOEVENT_REQUEST_VALID_FLAGS \
+	(GPIOEVENT_REQUEST_RISING_EDGE | \
+	GPIOEVENT_REQUEST_FALLING_EDGE)
+
+static unsigned int lineevent_poll(struct file *filep,
+				   struct poll_table_struct *wait)
+{
+	struct lineevent_state *le = filep->private_data;
+	unsigned int events = 0;
+
+	poll_wait(filep, &le->wait, wait);
+
+	if (!kfifo_is_empty(&le->events))
+		events = POLLIN | POLLRDNORM;
+
+	return events;
+}
+
+
+static ssize_t lineevent_read(struct file *filep,
+			      char __user *buf,
+			      size_t count,
+			      loff_t *f_ps)
+{
+	struct lineevent_state *le = filep->private_data;
+	unsigned int copied;
+	int ret;
+
+	if (count < sizeof(struct gpioevent_data))
+		return -EINVAL;
+
+	do {
+		if (kfifo_is_empty(&le->events)) {
+			if (filep->f_flags & O_NONBLOCK)
+				return -EAGAIN;
+
+			ret = wait_event_interruptible(le->wait,
+					!kfifo_is_empty(&le->events));
+			if (ret)
+				return ret;
+		}
+
+		if (mutex_lock_interruptible(&le->read_lock))
+			return -ERESTARTSYS;
+		ret = kfifo_to_user(&le->events, buf, count, &copied);
+		mutex_unlock(&le->read_lock);
+
+		if (ret)
+			return ret;
+
+		/*
+		 * If we couldn't read anything from the fifo (a different
+		 * thread might have been faster) we either return -EAGAIN if
+		 * the file descriptor is non-blocking, otherwise we go back to
+		 * sleep and wait for more data to arrive.
+		 */
+		if (copied == 0 && (filep->f_flags & O_NONBLOCK))
+			return -EAGAIN;
+
+	} while (copied == 0);
+
+	return copied;
+}
+
+static int lineevent_release(struct inode *inode, struct file *filep)
+{
+	struct lineevent_state *le = filep->private_data;
+	struct gpio_device *gdev = le->gdev;
+
+	free_irq(le->irq, le);
+	gpiod_free(le->desc);
+	kfree(le->label);
+	kfree(le);
+	put_device(&gdev->dev);
+	return 0;
+}
 
+static long lineevent_ioctl(struct file *filep, unsigned int cmd,
+			    unsigned long arg)
+{
+	struct lineevent_state *le = filep->private_data;
+	void __user *ip = (void __user *)arg;
+	struct gpiohandle_data ghd;
+
+	/*
+	 * We can get the value for an event line but not set it,
+	 * because it is input by definition.
+	 */
+	if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) {
+		int val;
+
+		memset(&ghd, 0, sizeof(ghd));
+
+		val = gpiod_get_value_cansleep(le->desc);
+		if (val < 0)
+			return val;
+		ghd.values[0] = val;
+
+		if (copy_to_user(ip, &ghd, sizeof(ghd)))
+			return -EFAULT;
+
+		return 0;
+	}
+	return -EINVAL;
+}
+
+#ifdef CONFIG_COMPAT
+static long lineevent_ioctl_compat(struct file *filep, unsigned int cmd,
+				   unsigned long arg)
+{
+	return lineevent_ioctl(filep, cmd, (unsigned long)compat_ptr(arg));
+}
+#endif
+
+static const struct file_operations lineevent_fileops = {
+	.release = lineevent_release,
+	.read = lineevent_read,
+	.poll = lineevent_poll,
+	.owner = THIS_MODULE,
+	.llseek = noop_llseek,
+	.unlocked_ioctl = lineevent_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl = lineevent_ioctl_compat,
+#endif
+};
+
+static irqreturn_t lineevent_irq_thread(int irq, void *p)
+{
+	struct lineevent_state *le = p;
+	struct gpioevent_data ge;
+	int ret;
+
+	ge.timestamp = ktime_get_real_ns();
+
+	if (le->eflags & GPIOEVENT_REQUEST_BOTH_EDGES) {
+		int level = gpiod_get_value_cansleep(le->desc);
+
+		if (level)
+			/* Emit low-to-high event */
+			ge.id = GPIOEVENT_EVENT_RISING_EDGE;
+		else
+			/* Emit high-to-low event */
+			ge.id = GPIOEVENT_EVENT_FALLING_EDGE;
+	} else if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE) {
+		/* Emit low-to-high event */
+		ge.id = GPIOEVENT_EVENT_RISING_EDGE;
+	} else if (le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE) {
+		/* Emit high-to-low event */
+		ge.id = GPIOEVENT_EVENT_FALLING_EDGE;
+	} else {
+		return IRQ_NONE;
+	}
+
+	ret = kfifo_put(&le->events, ge);
+	if (ret != 0)
+		wake_up_poll(&le->wait, POLLIN);
+
+	return IRQ_HANDLED;
+}
+
+static int lineevent_create(struct gpio_device *gdev, void __user *ip)
+{
+	struct gpioevent_request eventreq;
+	struct lineevent_state *le;
+	struct gpio_desc *desc;
+	struct file *file;
+	u32 offset;
+	u32 lflags;
+	u32 eflags;
+	int fd;
+	int ret;
+	int irqflags = 0;
+
+	if (copy_from_user(&eventreq, ip, sizeof(eventreq)))
+		return -EFAULT;
+
+	le = kzalloc(sizeof(*le), GFP_KERNEL);
+	if (!le)
+		return -ENOMEM;
+	le->gdev = gdev;
+	get_device(&gdev->dev);
+
+	/* Make sure this is terminated */
+	eventreq.consumer_label[sizeof(eventreq.consumer_label)-1] = '\0';
+	if (strlen(eventreq.consumer_label)) {
+		le->label = kstrdup(eventreq.consumer_label,
+				    GFP_KERNEL);
+		if (!le->label) {
+			ret = -ENOMEM;
+			goto out_free_le;
+		}
+	}
+
+	offset = eventreq.lineoffset;
+	lflags = eventreq.handleflags;
+	eflags = eventreq.eventflags;
+
+	if (offset >= gdev->ngpio) {
+		ret = -EINVAL;
+		goto out_free_label;
+	}
+
+	/* Return an error if a unknown flag is set */
+	if ((lflags & ~GPIOHANDLE_REQUEST_VALID_FLAGS) ||
+	    (eflags & ~GPIOEVENT_REQUEST_VALID_FLAGS)) {
+		ret = -EINVAL;
+		goto out_free_label;
+	}
+
+	/* This is just wrong: we don't look for events on output lines */
+	if (lflags & GPIOHANDLE_REQUEST_OUTPUT) {
+		ret = -EINVAL;
+		goto out_free_label;
+	}
+
+	desc = &gdev->descs[offset];
+	ret = gpiod_request(desc, le->label);
+	if (ret)
+		goto out_free_desc;
+	le->desc = desc;
+	le->eflags = eflags;
+
+	if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW)
+		set_bit(FLAG_ACTIVE_LOW, &desc->flags);
+	if (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN)
+		set_bit(FLAG_OPEN_DRAIN, &desc->flags);
+	if (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)
+		set_bit(FLAG_OPEN_SOURCE, &desc->flags);
+
+	ret = gpiod_direction_input(desc);
+	if (ret)
+		goto out_free_desc;
+
+	le->irq = gpiod_to_irq(desc);
+	if (le->irq <= 0) {
+		ret = -ENODEV;
+		goto out_free_desc;
+	}
+
+	if (eflags & GPIOEVENT_REQUEST_RISING_EDGE)
+		irqflags |= IRQF_TRIGGER_RISING;
+	if (eflags & GPIOEVENT_REQUEST_FALLING_EDGE)
+		irqflags |= IRQF_TRIGGER_FALLING;
+	irqflags |= IRQF_ONESHOT;
+	irqflags |= IRQF_SHARED;
+
+	INIT_KFIFO(le->events);
+	init_waitqueue_head(&le->wait);
+	mutex_init(&le->read_lock);
+
+	/* Request a thread to read the events */
+	ret = request_threaded_irq(le->irq,
+			NULL,
+			lineevent_irq_thread,
+			irqflags,
+			le->label,
+			le);
+	if (ret)
+		goto out_free_desc;
+
+	fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);
+	if (fd < 0) {
+		ret = fd;
+		goto out_free_irq;
+	}
+
+	file = anon_inode_getfile("gpio-event",
+				  &lineevent_fileops,
+				  le,
+				  O_RDONLY | O_CLOEXEC);
+	if (IS_ERR(file)) {
+		ret = PTR_ERR(file);
+		goto out_put_unused_fd;
+	}
+
+	eventreq.fd = fd;
+	if (copy_to_user(ip, &eventreq, sizeof(eventreq))) {
+		/*
+		 * fput() will trigger the release() callback, so do not go onto
+		 * the regular error cleanup path here.
+		 */
+		fput(file);
+		put_unused_fd(fd);
+		return -EFAULT;
+	}
+
+	fd_install(fd, file);
+
+	return 0;
+
+out_put_unused_fd:
+	put_unused_fd(fd);
+out_free_irq:
+	free_irq(le->irq, le);
+out_free_desc:
+	gpiod_free(le->desc);
+out_free_label:
+	kfree(le->label);
+out_free_le:
+	kfree(le);
+	put_device(&gdev->dev);
+	return ret;
+}
+
+/**
+ * gpio_ioctl() - ioctl handler for the GPIO chardev
+ */
+static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+{
+	struct gpio_device *gdev = filp->private_data;
+	struct gpio_chip *chip = gdev->chip;
+	void __user *ip = (void __user *)arg;
+
+	/* We fail any subsequent ioctl():s when the chip is gone */
+	if (!chip)
+		return -ENODEV;
+
+	/* Fill in the struct and pass to userspace */
+	if (cmd == GPIO_GET_CHIPINFO_IOCTL) {
+		struct gpiochip_info chipinfo;
+
+		memset(&chipinfo, 0, sizeof(chipinfo));
+
+		strncpy(chipinfo.name, dev_name(&gdev->dev),
+			sizeof(chipinfo.name));
+		chipinfo.name[sizeof(chipinfo.name)-1] = '\0';
+		strncpy(chipinfo.label, gdev->label,
+			sizeof(chipinfo.label));
+		chipinfo.label[sizeof(chipinfo.label)-1] = '\0';
+		chipinfo.lines = gdev->ngpio;
+		if (copy_to_user(ip, &chipinfo, sizeof(chipinfo)))
+			return -EFAULT;
+		return 0;
+	} else if (cmd == GPIO_GET_LINEINFO_IOCTL) {
+		struct gpioline_info lineinfo;
+		struct gpio_desc *desc;
+
+		if (copy_from_user(&lineinfo, ip, sizeof(lineinfo)))
+			return -EFAULT;
+		if (lineinfo.line_offset >= gdev->ngpio)
+			return -EINVAL;
+
+		desc = &gdev->descs[lineinfo.line_offset];
+		if (desc->name) {
+			strncpy(lineinfo.name, desc->name,
+				sizeof(lineinfo.name));
+			lineinfo.name[sizeof(lineinfo.name)-1] = '\0';
+		} else {
+			lineinfo.name[0] = '\0';
+		}
+		if (desc->label) {
+			strncpy(lineinfo.consumer, desc->label,
+				sizeof(lineinfo.consumer));
+			lineinfo.consumer[sizeof(lineinfo.consumer)-1] = '\0';
+		} else {
+			lineinfo.consumer[0] = '\0';
+		}
+
+		/*
+		 * Userspace only need to know that the kernel is using
+		 * this GPIO so it can't use it.
+		 */
+		lineinfo.flags = 0;
+		if (test_bit(FLAG_REQUESTED, &desc->flags) ||
+		    test_bit(FLAG_IS_HOGGED, &desc->flags) ||
+		    test_bit(FLAG_USED_AS_IRQ, &desc->flags) ||
+		    test_bit(FLAG_EXPORT, &desc->flags) ||
+		    test_bit(FLAG_SYSFS, &desc->flags))
+			lineinfo.flags |= GPIOLINE_FLAG_KERNEL;
+		if (test_bit(FLAG_IS_OUT, &desc->flags))
+			lineinfo.flags |= GPIOLINE_FLAG_IS_OUT;
+		if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
+			lineinfo.flags |= GPIOLINE_FLAG_ACTIVE_LOW;
+		if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
+			lineinfo.flags |= GPIOLINE_FLAG_OPEN_DRAIN;
+		if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
+			lineinfo.flags |= GPIOLINE_FLAG_OPEN_SOURCE;
+
+		if (copy_to_user(ip, &lineinfo, sizeof(lineinfo)))
+			return -EFAULT;
+		return 0;
+	} else if (cmd == GPIO_GET_LINEHANDLE_IOCTL) {
+		return linehandle_create(gdev, ip);
+	} else if (cmd == GPIO_GET_LINEEVENT_IOCTL) {
+		return lineevent_create(gdev, ip);
+	}
+	return -EINVAL;
+}
+
+#ifdef CONFIG_COMPAT
+static long gpio_ioctl_compat(struct file *filp, unsigned int cmd,
+			      unsigned long arg)
+{
+	return gpio_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
+}
+#endif
+
+/**
+ * gpio_chrdev_open() - open the chardev for ioctl operations
+ * @inode: inode for this chardev
+ * @filp: file struct for storing private data
+ * Returns 0 on success
+ */
+static int gpio_chrdev_open(struct inode *inode, struct file *filp)
+{
+	struct gpio_device *gdev = container_of(inode->i_cdev,
+					      struct gpio_device, chrdev);
+
+	/* Fail on open if the backing gpiochip is gone */
+	if (!gdev || !gdev->chip)
+		return -ENODEV;
+	get_device(&gdev->dev);
+	filp->private_data = gdev;
 	return 0;
 }
 
 /**
- * gpiochip_add() - register a gpio_chip
+ * gpio_chrdev_release() - close chardev after ioctl operations
+ * @inode: inode for this chardev
+ * @filp: file struct for storing private data
+ * Returns 0 on success
+ */
+static int gpio_chrdev_release(struct inode *inode, struct file *filp)
+{
+	struct gpio_device *gdev = container_of(inode->i_cdev,
+					      struct gpio_device, chrdev);
+
+	if (!gdev)
+		return -ENODEV;
+	put_device(&gdev->dev);
+	return 0;
+}
+
+
+static const struct file_operations gpio_fileops = {
+	.release = gpio_chrdev_release,
+	.open = gpio_chrdev_open,
+	.owner = THIS_MODULE,
+	.llseek = noop_llseek,
+	.unlocked_ioctl = gpio_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl = gpio_ioctl_compat,
+#endif
+};
+
+static void gpiodevice_release(struct device *dev)
+{
+	struct gpio_device *gdev = dev_get_drvdata(dev);
+
+	list_del(&gdev->list);
+	ida_simple_remove(&gpio_ida, gdev->id);
+	kfree(gdev->label);
+	kfree(gdev->descs);
+	kfree(gdev);
+}
+
+static int gpiochip_setup_dev(struct gpio_device *gdev)
+{
+	int status;
+
+	cdev_init(&gdev->chrdev, &gpio_fileops);
+	gdev->chrdev.owner = THIS_MODULE;
+	gdev->chrdev.kobj.parent = &gdev->dev.kobj;
+	gdev->dev.devt = MKDEV(MAJOR(gpio_devt), gdev->id);
+	status = cdev_add(&gdev->chrdev, gdev->dev.devt, 1);
+	if (status < 0)
+		chip_warn(gdev->chip, "failed to add char device %d:%d\n",
+			  MAJOR(gpio_devt), gdev->id);
+	else
+		chip_dbg(gdev->chip, "added GPIO chardev (%d:%d)\n",
+			 MAJOR(gpio_devt), gdev->id);
+	status = device_add(&gdev->dev);
+	if (status)
+		goto err_remove_chardev;
+
+	status = gpiochip_sysfs_register(gdev);
+	if (status)
+		goto err_remove_device;
+
+	/* From this point, the .release() function cleans up gpio_device */
+	gdev->dev.release = gpiodevice_release;
+	pr_debug("%s: registered GPIOs %d to %d on device: %s (%s)\n",
+		 __func__, gdev->base, gdev->base + gdev->ngpio - 1,
+		 dev_name(&gdev->dev), gdev->chip->label ? : "generic");
+
+	return 0;
+
+err_remove_device:
+	device_del(&gdev->dev);
+err_remove_chardev:
+	cdev_del(&gdev->chrdev);
+	return status;
+}
+
+static void gpiochip_setup_devs(void)
+{
+	struct gpio_device *gdev;
+	int err;
+
+	list_for_each_entry(gdev, &gpio_devices, list) {
+		err = gpiochip_setup_dev(gdev);
+		if (err)
+			pr_err("%s: Failed to initialize gpio device (%d)\n",
+			       dev_name(&gdev->dev), err);
+	}
+}
+
+/**
+ * gpiochip_add_data() - register a gpio_chip
  * @chip: the chip to register, with chip->base initialized
  * Context: potentially before irqs will work
  *
@@ -296,48 +1098,124 @@
  * because the chip->base is invalid or already associated with a
  * different chip.  Otherwise it returns zero as a success code.
  *
- * When gpiochip_add() is called very early during boot, so that GPIOs
- * can be freely used, the chip->dev device must be registered before
+ * When gpiochip_add_data() is called very early during boot, so that GPIOs
+ * can be freely used, the chip->parent device must be registered before
  * the gpio framework's arch_initcall().  Otherwise sysfs initialization
  * for GPIOs will fail rudely.
  *
+ * gpiochip_add_data() must only be called after gpiolib initialization,
+ * ie after core_initcall().
+ *
  * If chip->base is negative, this requests dynamic assignment of
  * a range of valid GPIOs.
  */
-int gpiochip_add(struct gpio_chip *chip)
+int gpiochip_add_data(struct gpio_chip *chip, void *data)
 {
 	unsigned long	flags;
 	int		status = 0;
-	unsigned	id;
+	unsigned	i;
 	int		base = chip->base;
-	struct gpio_desc *descs;
+	struct gpio_device *gdev;
 
-	descs = kcalloc(chip->ngpio, sizeof(descs[0]), GFP_KERNEL);
-	if (!descs)
+	/*
+	 * First: allocate and populate the internal stat container, and
+	 * set up the struct device.
+	 */
+	gdev = kzalloc(sizeof(*gdev), GFP_KERNEL);
+	if (!gdev)
 		return -ENOMEM;
+	gdev->dev.bus = &gpio_bus_type;
+	gdev->chip = chip;
+	chip->gpiodev = gdev;
+	if (chip->parent) {
+		gdev->dev.parent = chip->parent;
+		gdev->dev.of_node = chip->parent->of_node;
+	}
+
+#ifdef CONFIG_OF_GPIO
+	/* If the gpiochip has an assigned OF node this takes precedence */
+	if (chip->of_node)
+		gdev->dev.of_node = chip->of_node;
+#endif
+
+	gdev->id = ida_simple_get(&gpio_ida, 0, 0, GFP_KERNEL);
+	if (gdev->id < 0) {
+		status = gdev->id;
+		goto err_free_gdev;
+	}
+	dev_set_name(&gdev->dev, "gpiochip%d", gdev->id);
+	device_initialize(&gdev->dev);
+	dev_set_drvdata(&gdev->dev, gdev);
+	if (chip->parent && chip->parent->driver)
+		gdev->owner = chip->parent->driver->owner;
+	else if (chip->owner)
+		/* TODO: remove chip->owner */
+		gdev->owner = chip->owner;
+	else
+		gdev->owner = THIS_MODULE;
+
+	gdev->descs = kcalloc(chip->ngpio, sizeof(gdev->descs[0]), GFP_KERNEL);
+	if (!gdev->descs) {
+		status = -ENOMEM;
+		goto err_free_gdev;
+	}
+
+	if (chip->ngpio == 0) {
+		chip_err(chip, "tried to insert a GPIO chip with zero lines\n");
+		status = -EINVAL;
+		goto err_free_descs;
+	}
+
+	if (chip->label)
+		gdev->label = kstrdup(chip->label, GFP_KERNEL);
+	else
+		gdev->label = kstrdup("unknown", GFP_KERNEL);
+	if (!gdev->label) {
+		status = -ENOMEM;
+		goto err_free_descs;
+	}
+
+	gdev->ngpio = chip->ngpio;
+	gdev->data = data;
 
 	spin_lock_irqsave(&gpio_lock, flags);
 
+	/*
+	 * TODO: this allocates a Linux GPIO number base in the global
+	 * GPIO numberspace for this chip. In the long run we want to
+	 * get *rid* of this numberspace and use only descriptors, but
+	 * it may be a pipe dream. It will not happen before we get rid
+	 * of the sysfs interface anyways.
+	 */
 	if (base < 0) {
 		base = gpiochip_find_base(chip->ngpio);
 		if (base < 0) {
 			status = base;
 			spin_unlock_irqrestore(&gpio_lock, flags);
-			goto err_free_descs;
+			goto err_free_label;
 		}
+		/*
+		 * TODO: it should not be necessary to reflect the assigned
+		 * base outside of the GPIO subsystem. Go over drivers and
+		 * see if anyone makes use of this, else drop this and assign
+		 * a poison instead.
+		 */
 		chip->base = base;
 	}
+	gdev->base = base;
 
-	status = gpiochip_add_to_list(chip);
+	status = gpiodev_add_to_list(gdev);
 	if (status) {
 		spin_unlock_irqrestore(&gpio_lock, flags);
-		goto err_free_descs;
+		goto err_free_label;
 	}
 
-	for (id = 0; id < chip->ngpio; id++) {
-		struct gpio_desc *desc = &descs[id];
+	spin_unlock_irqrestore(&gpio_lock, flags);
+
+	for (i = 0; i < chip->ngpio; i++) {
+		struct gpio_desc *desc = &gdev->descs[i];
 
-		desc->chip = chip;
+		desc->gdev = gdev;
 
 		/* REVISIT: most hardware initializes GPIOs as inputs (often
 		 * with pullups enabled) so power usage is minimized. Linux
@@ -348,56 +1226,71 @@
 		desc->flags = !chip->direction_input ? (1 << FLAG_IS_OUT) : 0;
 	}
 
-	chip->desc = descs;
-
-	spin_unlock_irqrestore(&gpio_lock, flags);
-
 #ifdef CONFIG_PINCTRL
-	INIT_LIST_HEAD(&chip->pin_ranges);
+	INIT_LIST_HEAD(&gdev->pin_ranges);
 #endif
 
-	if (!chip->owner && chip->dev && chip->dev->driver)
-		chip->owner = chip->dev->driver->owner;
-
 	status = gpiochip_set_desc_names(chip);
 	if (status)
 		goto err_remove_from_list;
 
-	status = of_gpiochip_add(chip);
+	status = gpiochip_irqchip_init_valid_mask(chip);
 	if (status)
-		goto err_remove_chip;
-
-	acpi_gpiochip_add(chip);
+		goto err_remove_from_list;
 
-	status = gpiochip_sysfs_register(chip);
+	status = of_gpiochip_add(chip);
 	if (status)
 		goto err_remove_chip;
 
-	pr_debug("%s: registered GPIOs %d to %d on device: %s\n", __func__,
-		chip->base, chip->base + chip->ngpio - 1,
-		chip->label ? : "generic");
+	acpi_gpiochip_add(chip);
 
+	/*
+	 * By first adding the chardev, and then adding the device,
+	 * we get a device node entry in sysfs under
+	 * /sys/bus/gpio/devices/gpiochipN/dev that can be used for
+	 * coldplug of device nodes and other udev business.
+	 * We can do this only if gpiolib has been initialized.
+	 * Otherwise, defer until later.
+	 */
+	if (gpiolib_initialized) {
+		status = gpiochip_setup_dev(gdev);
+		if (status)
+			goto err_remove_chip;
+	}
 	return 0;
 
 err_remove_chip:
 	acpi_gpiochip_remove(chip);
 	gpiochip_free_hogs(chip);
 	of_gpiochip_remove(chip);
+	gpiochip_irqchip_free_valid_mask(chip);
 err_remove_from_list:
 	spin_lock_irqsave(&gpio_lock, flags);
-	list_del(&chip->list);
+	list_del(&gdev->list);
 	spin_unlock_irqrestore(&gpio_lock, flags);
-	chip->desc = NULL;
+err_free_label:
+	kfree(gdev->label);
 err_free_descs:
-	kfree(descs);
-
+	kfree(gdev->descs);
+err_free_gdev:
+	ida_simple_remove(&gpio_ida, gdev->id);
 	/* failures here can mean systems won't boot... */
 	pr_err("%s: GPIOs %d..%d (%s) failed to register\n", __func__,
-		chip->base, chip->base + chip->ngpio - 1,
-		chip->label ? : "generic");
+	       gdev->base, gdev->base + gdev->ngpio - 1,
+	       chip->label ? : "generic");
+	kfree(gdev);
 	return status;
 }
-EXPORT_SYMBOL_GPL(gpiochip_add);
+EXPORT_SYMBOL_GPL(gpiochip_add_data);
+
+/**
+ * gpiochip_get_data() - get per-subdriver data for the chip
+ */
+void *gpiochip_get_data(struct gpio_chip *chip)
+{
+	return chip->gpiodev->data;
+}
+EXPORT_SYMBOL_GPL(gpiochip_get_data);
 
 /**
  * gpiochip_remove() - unregister a gpio_chip
@@ -407,38 +1300,125 @@
  */
 void gpiochip_remove(struct gpio_chip *chip)
 {
+	struct gpio_device *gdev = chip->gpiodev;
 	struct gpio_desc *desc;
 	unsigned long	flags;
-	unsigned	id;
+	unsigned	i;
 	bool		requested = false;
 
-	gpiochip_sysfs_unregister(chip);
-
+	/* FIXME: should the legacy sysfs handling be moved to gpio_device? */
+	gpiochip_sysfs_unregister(gdev);
+	/* Numb the device, cancelling all outstanding operations */
+	gdev->chip = NULL;
 	gpiochip_irqchip_remove(chip);
-
 	acpi_gpiochip_remove(chip);
 	gpiochip_remove_pin_ranges(chip);
 	gpiochip_free_hogs(chip);
 	of_gpiochip_remove(chip);
+	/*
+	 * We accept no more calls into the driver from this point, so
+	 * NULL the driver data pointer
+	 */
+	gdev->data = NULL;
 
 	spin_lock_irqsave(&gpio_lock, flags);
-	for (id = 0; id < chip->ngpio; id++) {
-		desc = &chip->desc[id];
-		desc->chip = NULL;
+	for (i = 0; i < gdev->ngpio; i++) {
+		desc = &gdev->descs[i];
 		if (test_bit(FLAG_REQUESTED, &desc->flags))
 			requested = true;
 	}
-	list_del(&chip->list);
 	spin_unlock_irqrestore(&gpio_lock, flags);
 
 	if (requested)
-		dev_crit(chip->dev, "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
+		dev_crit(&gdev->dev,
+			 "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
 
-	kfree(chip->desc);
-	chip->desc = NULL;
+	/*
+	 * The gpiochip side puts its use of the device to rest here:
+	 * if there are no userspace clients, the chardev and device will
+	 * be removed, else it will be dangling until the last user is
+	 * gone.
+	 */
+	cdev_del(&gdev->chrdev);
+	device_del(&gdev->dev);
+	put_device(&gdev->dev);
 }
 EXPORT_SYMBOL_GPL(gpiochip_remove);
 
+static void devm_gpio_chip_release(struct device *dev, void *res)
+{
+	struct gpio_chip *chip = *(struct gpio_chip **)res;
+
+	gpiochip_remove(chip);
+}
+
+static int devm_gpio_chip_match(struct device *dev, void *res, void *data)
+
+{
+	struct gpio_chip **r = res;
+
+	if (!r || !*r) {
+		WARN_ON(!r || !*r);
+		return 0;
+	}
+
+	return *r == data;
+}
+
+/**
+ * devm_gpiochip_add_data() - Resource manager piochip_add_data()
+ * @dev: the device pointer on which irq_chip belongs to.
+ * @chip: the chip to register, with chip->base initialized
+ * Context: potentially before irqs will work
+ *
+ * Returns a negative errno if the chip can't be registered, such as
+ * because the chip->base is invalid or already associated with a
+ * different chip.  Otherwise it returns zero as a success code.
+ *
+ * The gpio chip automatically be released when the device is unbound.
+ */
+int devm_gpiochip_add_data(struct device *dev, struct gpio_chip *chip,
+			   void *data)
+{
+	struct gpio_chip **ptr;
+	int ret;
+
+	ptr = devres_alloc(devm_gpio_chip_release, sizeof(*ptr),
+			     GFP_KERNEL);
+	if (!ptr)
+		return -ENOMEM;
+
+	ret = gpiochip_add_data(chip, data);
+	if (ret < 0) {
+		devres_free(ptr);
+		return ret;
+	}
+
+	*ptr = chip;
+	devres_add(dev, ptr);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(devm_gpiochip_add_data);
+
+/**
+ * devm_gpiochip_remove() - Resource manager of gpiochip_remove()
+ * @dev: device for which which resource was allocated
+ * @chip: the chip to remove
+ *
+ * A gpio_chip with any GPIOs still requested may not be removed.
+ */
+void devm_gpiochip_remove(struct device *dev, struct gpio_chip *chip)
+{
+	int ret;
+
+	ret = devres_release(dev, devm_gpio_chip_release,
+			     devm_gpio_chip_match, chip);
+	if (!ret)
+		WARN_ON(ret);
+}
+EXPORT_SYMBOL_GPL(devm_gpiochip_remove);
+
 /**
  * gpiochip_find() - iterator for locating a specific gpio_chip
  * @data: data to pass to match function
@@ -454,17 +1434,17 @@
 				int (*match)(struct gpio_chip *chip,
 					     void *data))
 {
-	struct gpio_chip *chip;
+	struct gpio_device *gdev;
+	struct gpio_chip *chip = NULL;
 	unsigned long flags;
 
 	spin_lock_irqsave(&gpio_lock, flags);
-	list_for_each_entry(chip, &gpio_chips, list)
-		if (match(chip, data))
+	list_for_each_entry(gdev, &gpio_devices, list)
+		if (gdev->chip && match(gdev->chip, data)) {
+			chip = gdev->chip;
 			break;
+		}
 
-	/* No match? */
-	if (&chip->list == &gpio_chips)
-		chip = NULL;
 	spin_unlock_irqrestore(&gpio_lock, flags);
 
 	return chip;
@@ -489,6 +1469,40 @@
  * The following is irqchip helper code for gpiochips.
  */
 
+static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip)
+{
+	int i;
+
+	if (!gpiochip->irq_need_valid_mask)
+		return 0;
+
+	gpiochip->irq_valid_mask = kcalloc(BITS_TO_LONGS(gpiochip->ngpio),
+					   sizeof(long), GFP_KERNEL);
+	if (!gpiochip->irq_valid_mask)
+		return -ENOMEM;
+
+	/* Assume by default all GPIOs are valid */
+	for (i = 0; i < gpiochip->ngpio; i++)
+		set_bit(i, gpiochip->irq_valid_mask);
+
+	return 0;
+}
+
+static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip)
+{
+	kfree(gpiochip->irq_valid_mask);
+	gpiochip->irq_valid_mask = NULL;
+}
+
+static bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gpiochip,
+				       unsigned int offset)
+{
+	/* No mask means all valid */
+	if (likely(!gpiochip->irq_valid_mask))
+		return true;
+	return test_bit(offset, gpiochip->irq_valid_mask);
+}
+
 /**
  * gpiochip_set_chained_irqchip() - sets a chained irqchip to a gpiochip
  * @gpiochip: the gpiochip to set the irqchip chain to
@@ -530,9 +1544,12 @@
 	}
 
 	/* Set the parent IRQ for all affected IRQs */
-	for (offset = 0; offset < gpiochip->ngpio; offset++)
+	for (offset = 0; offset < gpiochip->ngpio; offset++) {
+		if (!gpiochip_irqchip_irq_valid(gpiochip, offset))
+			continue;
 		irq_set_parent(irq_find_mapping(gpiochip->irqdomain, offset),
 			       parent_irq);
+	}
 }
 EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip);
 
@@ -594,14 +1611,14 @@
 {
 	struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
 
-	if (!try_module_get(chip->owner))
+	if (!try_module_get(chip->gpiodev->owner))
 		return -ENODEV;
 
 	if (gpiochip_lock_as_irq(chip, d->hwirq)) {
 		chip_err(chip,
 			"unable to lock HW IRQ %lu for IRQ\n",
 			d->hwirq);
-		module_put(chip->owner);
+		module_put(chip->gpiodev->owner);
 		return -EINVAL;
 	}
 	return 0;
@@ -612,7 +1629,7 @@
 	struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
 
 	gpiochip_unlock_as_irq(chip, d->hwirq);
-	module_put(chip->owner);
+	module_put(chip->gpiodev->owner);
 }
 
 static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset)
@@ -639,9 +1656,12 @@
 
 	/* Remove all IRQ mappings and delete the domain */
 	if (gpiochip->irqdomain) {
-		for (offset = 0; offset < gpiochip->ngpio; offset++)
+		for (offset = 0; offset < gpiochip->ngpio; offset++) {
+			if (!gpiochip_irqchip_irq_valid(gpiochip, offset))
+				continue;
 			irq_dispose_mapping(
 				irq_find_mapping(gpiochip->irqdomain, offset));
+		}
 		irq_domain_remove(gpiochip->irqdomain);
 	}
 
@@ -650,6 +1670,8 @@
 		gpiochip->irqchip->irq_release_resources = NULL;
 		gpiochip->irqchip = NULL;
 	}
+
+	gpiochip_irqchip_free_valid_mask(gpiochip);
 }
 
 /**
@@ -685,25 +1707,36 @@
 			  struct lock_class_key *lock_key)
 {
 	struct device_node *of_node;
+	bool irq_base_set = false;
 	unsigned int offset;
 	unsigned irq_base = 0;
 
 	if (!gpiochip || !irqchip)
 		return -EINVAL;
 
-	if (!gpiochip->dev) {
+	if (!gpiochip->parent) {
 		pr_err("missing gpiochip .dev parent pointer\n");
 		return -EINVAL;
 	}
-	of_node = gpiochip->dev->of_node;
+	of_node = gpiochip->parent->of_node;
 #ifdef CONFIG_OF_GPIO
 	/*
 	 * If the gpiochip has an assigned OF node this takes precedence
-	 * FIXME: get rid of this and use gpiochip->dev->of_node everywhere
+	 * FIXME: get rid of this and use gpiochip->parent->of_node
+	 * everywhere
 	 */
 	if (gpiochip->of_node)
 		of_node = gpiochip->of_node;
 #endif
+	/*
+	 * Specifying a default trigger is a terrible idea if DT is
+	 * used to configure the interrupts, as you may end-up with
+	 * conflicting triggers. Tell the user, and reset to NONE.
+	 */
+	if (WARN(of_node && type != IRQ_TYPE_NONE,
+		 "%s: Ignoring %d default trigger\n", of_node->full_name, type))
+		type = IRQ_TYPE_NONE;
+
 	gpiochip->irqchip = irqchip;
 	gpiochip->irq_handler = handler;
 	gpiochip->irq_default_type = type;
@@ -733,13 +1766,17 @@
 	 * necessary to allocate descriptors for all IRQs.
 	 */
 	for (offset = 0; offset < gpiochip->ngpio; offset++) {
+		if (!gpiochip_irqchip_irq_valid(gpiochip, offset))
+			continue;
 		irq_base = irq_create_mapping(gpiochip->irqdomain, offset);
-		if (offset == 0)
+		if (!irq_base_set) {
 			/*
 			 * Store the base into the gpiochip to be used when
 			 * unmapping the irqs.
 			 */
 			gpiochip->irq_base = irq_base;
+			irq_base_set = true;
+		}
 	}
 
 	acpi_gpiochip_request_interrupts(gpiochip);
@@ -751,6 +1788,12 @@
 #else /* CONFIG_GPIOLIB_IRQCHIP */
 
 static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) {}
+static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip)
+{
+	return 0;
+}
+static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip)
+{ }
 
 #endif /* CONFIG_GPIOLIB_IRQCHIP */
 
@@ -761,7 +1804,7 @@
  */
 int gpiochip_generic_request(struct gpio_chip *chip, unsigned offset)
 {
-	return pinctrl_request_gpio(chip->base + offset);
+	return pinctrl_request_gpio(chip->gpiodev->base + offset);
 }
 EXPORT_SYMBOL_GPL(gpiochip_generic_request);
 
@@ -772,7 +1815,7 @@
  */
 void gpiochip_generic_free(struct gpio_chip *chip, unsigned offset)
 {
-	pinctrl_free_gpio(chip->base + offset);
+	pinctrl_free_gpio(chip->gpiodev->base + offset);
 }
 EXPORT_SYMBOL_GPL(gpiochip_generic_free);
 
@@ -790,6 +1833,7 @@
 			unsigned int gpio_offset, const char *pin_group)
 {
 	struct gpio_pin_range *pin_range;
+	struct gpio_device *gdev = chip->gpiodev;
 	int ret;
 
 	pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
@@ -802,7 +1846,7 @@
 	pin_range->range.id = gpio_offset;
 	pin_range->range.gc = chip;
 	pin_range->range.name = chip->label;
-	pin_range->range.base = chip->base + gpio_offset;
+	pin_range->range.base = gdev->base + gpio_offset;
 	pin_range->pctldev = pctldev;
 
 	ret = pinctrl_get_group_pins(pctldev, pin_group,
@@ -819,7 +1863,7 @@
 		 gpio_offset, gpio_offset + pin_range->range.npins - 1,
 		 pinctrl_dev_get_devname(pctldev), pin_group);
 
-	list_add_tail(&pin_range->node, &chip->pin_ranges);
+	list_add_tail(&pin_range->node, &gdev->pin_ranges);
 
 	return 0;
 }
@@ -839,6 +1883,7 @@
 			   unsigned int npins)
 {
 	struct gpio_pin_range *pin_range;
+	struct gpio_device *gdev = chip->gpiodev;
 	int ret;
 
 	pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
@@ -851,7 +1896,7 @@
 	pin_range->range.id = gpio_offset;
 	pin_range->range.gc = chip;
 	pin_range->range.name = chip->label;
-	pin_range->range.base = chip->base + gpio_offset;
+	pin_range->range.base = gdev->base + gpio_offset;
 	pin_range->range.pin_base = pin_offset;
 	pin_range->range.npins = npins;
 	pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name,
@@ -867,7 +1912,7 @@
 		 pinctl_name,
 		 pin_offset, pin_offset + npins - 1);
 
-	list_add_tail(&pin_range->node, &chip->pin_ranges);
+	list_add_tail(&pin_range->node, &gdev->pin_ranges);
 
 	return 0;
 }
@@ -880,8 +1925,9 @@
 void gpiochip_remove_pin_ranges(struct gpio_chip *chip)
 {
 	struct gpio_pin_range *pin_range, *tmp;
+	struct gpio_device *gdev = chip->gpiodev;
 
-	list_for_each_entry_safe(pin_range, tmp, &chip->pin_ranges, node) {
+	list_for_each_entry_safe(pin_range, tmp, &gdev->pin_ranges, node) {
 		list_del(&pin_range->node);
 		pinctrl_remove_gpio_range(pin_range->pctldev,
 				&pin_range->range);
@@ -898,7 +1944,7 @@
  */
 static int __gpiod_request(struct gpio_desc *desc, const char *label)
 {
-	struct gpio_chip	*chip = desc->chip;
+	struct gpio_chip	*chip = desc->gdev->chip;
 	int			status;
 	unsigned long		flags;
 
@@ -939,27 +1985,63 @@
 	return status;
 }
 
+/*
+ * This descriptor validation needs to be inserted verbatim into each
+ * function taking a descriptor, so we need to use a preprocessor
+ * macro to avoid endless duplication. If the desc is NULL it is an
+ * optional GPIO and calls should just bail out.
+ */
+#define VALIDATE_DESC(desc) do { \
+	if (!desc) \
+		return 0; \
+	if (IS_ERR(desc)) {						\
+		pr_warn("%s: invalid GPIO (errorpointer)\n", __func__); \
+		return PTR_ERR(desc); \
+	} \
+	if (!desc->gdev) { \
+		pr_warn("%s: invalid GPIO (no device)\n", __func__); \
+		return -EINVAL; \
+	} \
+	if ( !desc->gdev->chip ) { \
+		dev_warn(&desc->gdev->dev, \
+			 "%s: backing chip is gone\n", __func__); \
+		return 0; \
+	} } while (0)
+
+#define VALIDATE_DESC_VOID(desc) do { \
+	if (!desc) \
+		return; \
+	if (IS_ERR(desc)) {						\
+		pr_warn("%s: invalid GPIO (errorpointer)\n", __func__); \
+		return; \
+	} \
+	if (!desc->gdev) { \
+		pr_warn("%s: invalid GPIO (no device)\n", __func__); \
+		return; \
+	} \
+	if (!desc->gdev->chip) { \
+		dev_warn(&desc->gdev->dev, \
+			 "%s: backing chip is gone\n", __func__); \
+		return; \
+	} } while (0)
+
+
 int gpiod_request(struct gpio_desc *desc, const char *label)
 {
 	int status = -EPROBE_DEFER;
-	struct gpio_chip *chip;
-
-	if (!desc) {
-		pr_warn("%s: invalid GPIO\n", __func__);
-		return -EINVAL;
-	}
+	struct gpio_device *gdev;
 
-	chip = desc->chip;
-	if (!chip)
-		goto done;
+	VALIDATE_DESC(desc);
+	gdev = desc->gdev;
 
-	if (try_module_get(chip->owner)) {
+	if (try_module_get(gdev->owner)) {
 		status = __gpiod_request(desc, label);
 		if (status < 0)
-			module_put(chip->owner);
+			module_put(gdev->owner);
+		else
+			get_device(&gdev->dev);
 	}
 
-done:
 	if (status)
 		gpiod_dbg(desc, "%s: status %d\n", __func__, status);
 
@@ -978,7 +2060,7 @@
 
 	spin_lock_irqsave(&gpio_lock, flags);
 
-	chip = desc->chip;
+	chip = desc->gdev->chip;
 	if (chip && test_bit(FLAG_REQUESTED, &desc->flags)) {
 		if (chip->free) {
 			spin_unlock_irqrestore(&gpio_lock, flags);
@@ -1001,10 +2083,12 @@
 
 void gpiod_free(struct gpio_desc *desc)
 {
-	if (desc && __gpiod_free(desc))
-		module_put(desc->chip->owner);
-	else
+	if (desc && desc->gdev && __gpiod_free(desc)) {
+		module_put(desc->gdev->owner);
+		put_device(&desc->gdev->dev);
+	} else {
 		WARN_ON(extra_checks);
+	}
 }
 
 /**
@@ -1027,7 +2111,7 @@
 	if (offset >= chip->ngpio)
 		return NULL;
 
-	desc = &chip->desc[offset];
+	desc = &chip->gpiodev->descs[offset];
 
 	if (test_bit(FLAG_REQUESTED, &desc->flags) == 0)
 		return NULL;
@@ -1079,7 +2163,8 @@
 }
 EXPORT_SYMBOL_GPL(gpiochip_free_own_desc);
 
-/* Drivers MUST set GPIO direction before making get/set calls.  In
+/*
+ * Drivers MUST set GPIO direction before making get/set calls.  In
  * some cases this is done in early boot, before IRQs are enabled.
  *
  * As a rule these aren't called more than once (except for drivers
@@ -1102,12 +2187,9 @@
 	struct gpio_chip	*chip;
 	int			status = -EINVAL;
 
-	if (!desc || !desc->chip) {
-		pr_warn("%s: invalid GPIO\n", __func__);
-		return -EINVAL;
-	}
+	VALIDATE_DESC(desc);
+	chip = desc->gdev->chip;
 
-	chip = desc->chip;
 	if (!chip->get || !chip->direction_input) {
 		gpiod_warn(desc,
 			"%s: missing get() or direction_input() operations\n",
@@ -1127,8 +2209,8 @@
 
 static int _gpiod_direction_output_raw(struct gpio_desc *desc, int value)
 {
-	struct gpio_chip	*chip;
-	int			status = -EINVAL;
+	struct gpio_chip *gc = desc->gdev->chip;
+	int ret;
 
 	/* GPIOs used for IRQs shall not be set as output */
 	if (test_bit(FLAG_USED_AS_IRQ, &desc->flags)) {
@@ -1138,28 +2220,50 @@
 		return -EIO;
 	}
 
-	/* Open drain pin should not be driven to 1 */
-	if (value && test_bit(FLAG_OPEN_DRAIN,  &desc->flags))
-		return gpiod_direction_input(desc);
-
-	/* Open source pin should not be driven to 0 */
-	if (!value && test_bit(FLAG_OPEN_SOURCE,  &desc->flags))
-		return gpiod_direction_input(desc);
+	if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
+		/* First see if we can enable open drain in hardware */
+		if (gc->set_single_ended) {
+			ret = gc->set_single_ended(gc, gpio_chip_hwgpio(desc),
+						   LINE_MODE_OPEN_DRAIN);
+			if (!ret)
+				goto set_output_value;
+		}
+		/* Emulate open drain by not actively driving the line high */
+		if (value)
+			return gpiod_direction_input(desc);
+	}
+	else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) {
+		if (gc->set_single_ended) {
+			ret = gc->set_single_ended(gc, gpio_chip_hwgpio(desc),
+						   LINE_MODE_OPEN_SOURCE);
+			if (!ret)
+				goto set_output_value;
+		}
+		/* Emulate open source by not actively driving the line low */
+		if (!value)
+			return gpiod_direction_input(desc);
+	} else {
+		/* Make sure to disable open drain/source hardware, if any */
+		if (gc->set_single_ended)
+			gc->set_single_ended(gc,
+					     gpio_chip_hwgpio(desc),
+					     LINE_MODE_PUSH_PULL);
+	}
 
-	chip = desc->chip;
-	if (!chip->set || !chip->direction_output) {
+set_output_value:
+	if (!gc->set || !gc->direction_output) {
 		gpiod_warn(desc,
 		       "%s: missing set() or direction_output() operations\n",
 		       __func__);
 		return -EIO;
 	}
 
-	status = chip->direction_output(chip, gpio_chip_hwgpio(desc), value);
-	if (status == 0)
+	ret = gc->direction_output(gc, gpio_chip_hwgpio(desc), value);
+	if (!ret)
 		set_bit(FLAG_IS_OUT, &desc->flags);
 	trace_gpio_value(desc_to_gpio(desc), 0, value);
-	trace_gpio_direction(desc_to_gpio(desc), 0, status);
-	return status;
+	trace_gpio_direction(desc_to_gpio(desc), 0, ret);
+	return ret;
 }
 
 /**
@@ -1175,10 +2279,7 @@
  */
 int gpiod_direction_output_raw(struct gpio_desc *desc, int value)
 {
-	if (!desc || !desc->chip) {
-		pr_warn("%s: invalid GPIO\n", __func__);
-		return -EINVAL;
-	}
+	VALIDATE_DESC(desc);
 	return _gpiod_direction_output_raw(desc, value);
 }
 EXPORT_SYMBOL_GPL(gpiod_direction_output_raw);
@@ -1197,10 +2298,7 @@
  */
 int gpiod_direction_output(struct gpio_desc *desc, int value)
 {
-	if (!desc || !desc->chip) {
-		pr_warn("%s: invalid GPIO\n", __func__);
-		return -EINVAL;
-	}
+	VALIDATE_DESC(desc);
 	if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
 		value = !value;
 	return _gpiod_direction_output_raw(desc, value);
@@ -1219,12 +2317,8 @@
 {
 	struct gpio_chip	*chip;
 
-	if (!desc || !desc->chip) {
-		pr_warn("%s: invalid GPIO\n", __func__);
-		return -EINVAL;
-	}
-
-	chip = desc->chip;
+	VALIDATE_DESC(desc);
+	chip = desc->gdev->chip;
 	if (!chip->set || !chip->set_debounce) {
 		gpiod_dbg(desc,
 			  "%s: missing set() or set_debounce() operations\n",
@@ -1244,6 +2338,7 @@
  */
 int gpiod_is_active_low(const struct gpio_desc *desc)
 {
+	VALIDATE_DESC(desc);
 	return test_bit(FLAG_ACTIVE_LOW, &desc->flags);
 }
 EXPORT_SYMBOL_GPL(gpiod_is_active_low);
@@ -1276,7 +2371,7 @@
 	int offset;
 	int value;
 
-	chip = desc->chip;
+	chip = desc->gdev->chip;
 	offset = gpio_chip_hwgpio(desc);
 	value = chip->get ? chip->get(chip, offset) : -EIO;
 	/*
@@ -1302,10 +2397,9 @@
  */
 int gpiod_get_raw_value(const struct gpio_desc *desc)
 {
-	if (!desc)
-		return 0;
+	VALIDATE_DESC(desc);
 	/* Should be using gpio_get_value_cansleep() */
-	WARN_ON(desc->chip->can_sleep);
+	WARN_ON(desc->gdev->chip->can_sleep);
 	return _gpiod_get_raw_value(desc);
 }
 EXPORT_SYMBOL_GPL(gpiod_get_raw_value);
@@ -1323,10 +2417,10 @@
 int gpiod_get_value(const struct gpio_desc *desc)
 {
 	int value;
-	if (!desc)
-		return 0;
+
+	VALIDATE_DESC(desc);
 	/* Should be using gpio_get_value_cansleep() */
-	WARN_ON(desc->chip->can_sleep);
+	WARN_ON(desc->gdev->chip->can_sleep);
 
 	value = _gpiod_get_raw_value(desc);
 	if (value < 0)
@@ -1347,7 +2441,7 @@
 static void _gpio_set_open_drain_value(struct gpio_desc *desc, bool value)
 {
 	int err = 0;
-	struct gpio_chip *chip = desc->chip;
+	struct gpio_chip *chip = desc->gdev->chip;
 	int offset = gpio_chip_hwgpio(desc);
 
 	if (value) {
@@ -1374,7 +2468,7 @@
 static void _gpio_set_open_source_value(struct gpio_desc *desc, bool value)
 {
 	int err = 0;
-	struct gpio_chip *chip = desc->chip;
+	struct gpio_chip *chip = desc->gdev->chip;
 	int offset = gpio_chip_hwgpio(desc);
 
 	if (value) {
@@ -1397,7 +2491,7 @@
 {
 	struct gpio_chip	*chip;
 
-	chip = desc->chip;
+	chip = desc->gdev->chip;
 	trace_gpio_value(desc_to_gpio(desc), 0, value);
 	if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
 		_gpio_set_open_drain_value(desc, value);
@@ -1437,15 +2531,15 @@
 	}
 }
 
-static void gpiod_set_array_value_priv(bool raw, bool can_sleep,
-				       unsigned int array_size,
-				       struct gpio_desc **desc_array,
-				       int *value_array)
+void gpiod_set_array_value_complex(bool raw, bool can_sleep,
+				   unsigned int array_size,
+				   struct gpio_desc **desc_array,
+				   int *value_array)
 {
 	int i = 0;
 
 	while (i < array_size) {
-		struct gpio_chip *chip = desc_array[i]->chip;
+		struct gpio_chip *chip = desc_array[i]->gdev->chip;
 		unsigned long mask[BITS_TO_LONGS(chip->ngpio)];
 		unsigned long bits[BITS_TO_LONGS(chip->ngpio)];
 		int count = 0;
@@ -1479,7 +2573,8 @@
 				count++;
 			}
 			i++;
-		} while ((i < array_size) && (desc_array[i]->chip == chip));
+		} while ((i < array_size) &&
+			 (desc_array[i]->gdev->chip == chip));
 		/* push collected bits to outputs */
 		if (count != 0)
 			gpio_chip_set_multiple(chip, mask, bits);
@@ -1499,10 +2594,9 @@
  */
 void gpiod_set_raw_value(struct gpio_desc *desc, int value)
 {
-	if (!desc)
-		return;
+	VALIDATE_DESC_VOID(desc);
 	/* Should be using gpio_set_value_cansleep() */
-	WARN_ON(desc->chip->can_sleep);
+	WARN_ON(desc->gdev->chip->can_sleep);
 	_gpiod_set_raw_value(desc, value);
 }
 EXPORT_SYMBOL_GPL(gpiod_set_raw_value);
@@ -1520,10 +2614,9 @@
  */
 void gpiod_set_value(struct gpio_desc *desc, int value)
 {
-	if (!desc)
-		return;
+	VALIDATE_DESC_VOID(desc);
 	/* Should be using gpio_set_value_cansleep() */
-	WARN_ON(desc->chip->can_sleep);
+	WARN_ON(desc->gdev->chip->can_sleep);
 	if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
 		value = !value;
 	_gpiod_set_raw_value(desc, value);
@@ -1547,8 +2640,8 @@
 {
 	if (!desc_array)
 		return;
-	gpiod_set_array_value_priv(true, false, array_size, desc_array,
-				   value_array);
+	gpiod_set_array_value_complex(true, false, array_size, desc_array,
+				      value_array);
 }
 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value);
 
@@ -1569,8 +2662,8 @@
 {
 	if (!desc_array)
 		return;
-	gpiod_set_array_value_priv(false, false, array_size, desc_array,
-				   value_array);
+	gpiod_set_array_value_complex(false, false, array_size, desc_array,
+				      value_array);
 }
 EXPORT_SYMBOL_GPL(gpiod_set_array_value);
 
@@ -1581,9 +2674,8 @@
  */
 int gpiod_cansleep(const struct gpio_desc *desc)
 {
-	if (!desc)
-		return 0;
-	return desc->chip->can_sleep;
+	VALIDATE_DESC(desc);
+	return desc->gdev->chip->can_sleep;
 }
 EXPORT_SYMBOL_GPL(gpiod_cansleep);
 
@@ -1596,14 +2688,29 @@
  */
 int gpiod_to_irq(const struct gpio_desc *desc)
 {
-	struct gpio_chip	*chip;
-	int			offset;
+	struct gpio_chip *chip;
+	int offset;
 
-	if (!desc)
+	/*
+	 * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics
+	 * requires this function to not return zero on an invalid descriptor
+	 * but rather a negative error number.
+	 */
+	if (!desc || IS_ERR(desc) || !desc->gdev || !desc->gdev->chip)
 		return -EINVAL;
-	chip = desc->chip;
+
+	chip = desc->gdev->chip;
 	offset = gpio_chip_hwgpio(desc);
-	return chip->to_irq ? chip->to_irq(chip, offset) : -ENXIO;
+	if (chip->to_irq) {
+		int retirq = chip->to_irq(chip, offset);
+
+		/* Zero means NO_IRQ */
+		if (!retirq)
+			return -ENXIO;
+
+		return retirq;
+	}
+	return -ENXIO;
 }
 EXPORT_SYMBOL_GPL(gpiod_to_irq);
 
@@ -1617,17 +2724,30 @@
  */
 int gpiochip_lock_as_irq(struct gpio_chip *chip, unsigned int offset)
 {
-	if (offset >= chip->ngpio)
-		return -EINVAL;
+	struct gpio_desc *desc;
+
+	desc = gpiochip_get_desc(chip, offset);
+	if (IS_ERR(desc))
+		return PTR_ERR(desc);
 
-	if (test_bit(FLAG_IS_OUT, &chip->desc[offset].flags)) {
+	/* Flush direction if something changed behind our back */
+	if (chip->get_direction) {
+		int dir = chip->get_direction(chip, offset);
+
+		if (dir)
+			clear_bit(FLAG_IS_OUT, &desc->flags);
+		else
+			set_bit(FLAG_IS_OUT, &desc->flags);
+	}
+
+	if (test_bit(FLAG_IS_OUT, &desc->flags)) {
 		chip_err(chip,
 			  "%s: tried to flag a GPIO set as output for IRQ\n",
 			  __func__);
 		return -EIO;
 	}
 
-	set_bit(FLAG_USED_AS_IRQ, &chip->desc[offset].flags);
+	set_bit(FLAG_USED_AS_IRQ, &desc->flags);
 	return 0;
 }
 EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq);
@@ -1645,10 +2765,37 @@
 	if (offset >= chip->ngpio)
 		return;
 
-	clear_bit(FLAG_USED_AS_IRQ, &chip->desc[offset].flags);
+	clear_bit(FLAG_USED_AS_IRQ, &chip->gpiodev->descs[offset].flags);
 }
 EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq);
 
+bool gpiochip_line_is_irq(struct gpio_chip *chip, unsigned int offset)
+{
+	if (offset >= chip->ngpio)
+		return false;
+
+	return test_bit(FLAG_USED_AS_IRQ, &chip->gpiodev->descs[offset].flags);
+}
+EXPORT_SYMBOL_GPL(gpiochip_line_is_irq);
+
+bool gpiochip_line_is_open_drain(struct gpio_chip *chip, unsigned int offset)
+{
+	if (offset >= chip->ngpio)
+		return false;
+
+	return test_bit(FLAG_OPEN_DRAIN, &chip->gpiodev->descs[offset].flags);
+}
+EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain);
+
+bool gpiochip_line_is_open_source(struct gpio_chip *chip, unsigned int offset)
+{
+	if (offset >= chip->ngpio)
+		return false;
+
+	return test_bit(FLAG_OPEN_SOURCE, &chip->gpiodev->descs[offset].flags);
+}
+EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source);
+
 /**
  * gpiod_get_raw_value_cansleep() - return a gpio's raw value
  * @desc: gpio whose value will be returned
@@ -1661,8 +2808,7 @@
 int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc)
 {
 	might_sleep_if(extra_checks);
-	if (!desc)
-		return 0;
+	VALIDATE_DESC(desc);
 	return _gpiod_get_raw_value(desc);
 }
 EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep);
@@ -1681,9 +2827,7 @@
 	int value;
 
 	might_sleep_if(extra_checks);
-	if (!desc)
-		return 0;
-
+	VALIDATE_DESC(desc);
 	value = _gpiod_get_raw_value(desc);
 	if (value < 0)
 		return value;
@@ -1708,8 +2852,7 @@
 void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value)
 {
 	might_sleep_if(extra_checks);
-	if (!desc)
-		return;
+	VALIDATE_DESC_VOID(desc);
 	_gpiod_set_raw_value(desc, value);
 }
 EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep);
@@ -1727,9 +2870,7 @@
 void gpiod_set_value_cansleep(struct gpio_desc *desc, int value)
 {
 	might_sleep_if(extra_checks);
-	if (!desc)
-		return;
-
+	VALIDATE_DESC_VOID(desc);
 	if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
 		value = !value;
 	_gpiod_set_raw_value(desc, value);
@@ -1754,8 +2895,8 @@
 	might_sleep_if(extra_checks);
 	if (!desc_array)
 		return;
-	gpiod_set_array_value_priv(true, true, array_size, desc_array,
-				   value_array);
+	gpiod_set_array_value_complex(true, true, array_size, desc_array,
+				      value_array);
 }
 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep);
 
@@ -1777,8 +2918,8 @@
 	might_sleep_if(extra_checks);
 	if (!desc_array)
 		return;
-	gpiod_set_array_value_priv(false, true, array_size, desc_array,
-				   value_array);
+	gpiod_set_array_value_complex(false, true, array_size, desc_array,
+				      value_array);
 }
 EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep);
 
@@ -1794,6 +2935,7 @@
 
 	mutex_unlock(&gpio_lookup_lock);
 }
+EXPORT_SYMBOL_GPL(gpiod_add_lookup_table);
 
 /**
  * gpiod_remove_lookup_table() - unregister GPIO device consumers
@@ -1807,6 +2949,7 @@
 
 	mutex_unlock(&gpio_lookup_lock);
 }
+EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table);
 
 static struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id,
 				      unsigned int idx,
@@ -1827,7 +2970,7 @@
 
 		desc = of_get_named_gpiod_flags(dev->of_node, prop_name, idx,
 						&of_flags);
-		if (!IS_ERR(desc) || (PTR_ERR(desc) == -EPROBE_DEFER))
+		if (!IS_ERR(desc) || (PTR_ERR(desc) != -ENOENT))
 			break;
 	}
 
@@ -2324,8 +3467,8 @@
 	int id;
 
 	for (id = 0; id < chip->ngpio; id++) {
-		if (test_bit(FLAG_IS_HOGGED, &chip->desc[id].flags))
-			gpiochip_free_own_desc(&chip->desc[id]);
+		if (test_bit(FLAG_IS_HOGGED, &chip->gpiodev->descs[id].flags))
+			gpiochip_free_own_desc(&chip->gpiodev->descs[id]);
 	}
 }
 
@@ -2422,17 +3565,41 @@
 }
 EXPORT_SYMBOL_GPL(gpiod_put_array);
 
+static int __init gpiolib_dev_init(void)
+{
+	int ret;
+
+	/* Register GPIO sysfs bus */
+	ret  = bus_register(&gpio_bus_type);
+	if (ret < 0) {
+		pr_err("gpiolib: could not register GPIO bus type\n");
+		return ret;
+	}
+
+	ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, "gpiochip");
+	if (ret < 0) {
+		pr_err("gpiolib: failed to allocate char dev region\n");
+		bus_unregister(&gpio_bus_type);
+	} else {
+		gpiolib_initialized = true;
+		gpiochip_setup_devs();
+	}
+	return ret;
+}
+core_initcall(gpiolib_dev_init);
+
 #ifdef CONFIG_DEBUG_FS
 
-static void gpiolib_dbg_show(struct seq_file *s, struct gpio_chip *chip)
+static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev)
 {
 	unsigned		i;
-	unsigned		gpio = chip->base;
-	struct gpio_desc	*gdesc = &chip->desc[0];
+	struct gpio_chip	*chip = gdev->chip;
+	unsigned		gpio = gdev->base;
+	struct gpio_desc	*gdesc = &gdev->descs[0];
 	int			is_out;
 	int			is_irq;
 
-	for (i = 0; i < chip->ngpio; i++, gpio++, gdesc++) {
+	for (i = 0; i < gdev->ngpio; i++, gpio++, gdesc++) {
 		if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) {
 			if (gdesc->name) {
 				seq_printf(s, " gpio-%-3d (%-20.20s)\n",
@@ -2458,16 +3625,16 @@
 static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos)
 {
 	unsigned long flags;
-	struct gpio_chip *chip = NULL;
+	struct gpio_device *gdev = NULL;
 	loff_t index = *pos;
 
 	s->private = "";
 
 	spin_lock_irqsave(&gpio_lock, flags);
-	list_for_each_entry(chip, &gpio_chips, list)
+	list_for_each_entry(gdev, &gpio_devices, list)
 		if (index-- == 0) {
 			spin_unlock_irqrestore(&gpio_lock, flags);
-			return chip;
+			return gdev;
 		}
 	spin_unlock_irqrestore(&gpio_lock, flags);
 
@@ -2477,14 +3644,14 @@
 static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos)
 {
 	unsigned long flags;
-	struct gpio_chip *chip = v;
+	struct gpio_device *gdev = v;
 	void *ret = NULL;
 
 	spin_lock_irqsave(&gpio_lock, flags);
-	if (list_is_last(&chip->list, &gpio_chips))
+	if (list_is_last(&gdev->list, &gpio_devices))
 		ret = NULL;
 	else
-		ret = list_entry(chip->list.next, struct gpio_chip, list);
+		ret = list_entry(gdev->list.next, struct gpio_device, list);
 	spin_unlock_irqrestore(&gpio_lock, flags);
 
 	s->private = "\n";
@@ -2499,15 +3666,24 @@
 
 static int gpiolib_seq_show(struct seq_file *s, void *v)
 {
-	struct gpio_chip *chip = v;
-	struct device *dev;
+	struct gpio_device *gdev = v;
+	struct gpio_chip *chip = gdev->chip;
+	struct device *parent;
+
+	if (!chip) {
+		seq_printf(s, "%s%s: (dangling chip)", (char *)s->private,
+			   dev_name(&gdev->dev));
+		return 0;
+	}
 
-	seq_printf(s, "%sGPIOs %d-%d", (char *)s->private,
-			chip->base, chip->base + chip->ngpio - 1);
-	dev = chip->dev;
-	if (dev)
-		seq_printf(s, ", %s/%s", dev->bus ? dev->bus->name : "no-bus",
-			dev_name(dev));
+	seq_printf(s, "%s%s: GPIOs %d-%d", (char *)s->private,
+		   dev_name(&gdev->dev),
+		   gdev->base, gdev->base + gdev->ngpio - 1);
+	parent = chip->parent;
+	if (parent)
+		seq_printf(s, ", parent: %s/%s",
+			   parent->bus ? parent->bus->name : "no-bus",
+			   dev_name(parent));
 	if (chip->label)
 		seq_printf(s, ", %s", chip->label);
 	if (chip->can_sleep)
@@ -2517,7 +3693,7 @@
 	if (chip->dbg_show)
 		chip->dbg_show(s, chip);
 	else
-		gpiolib_dbg_show(s, chip);
+		gpiolib_dbg_show(s, gdev);
 
 	return 0;
 }