1 files changed, 679 insertions, 403 deletions

diff --git a/drivers/gpio/gpiolib-sysfs.c b/drivers/gpio/gpiolib-sysfs.c
index fbf6b1a0a4fa..cd553acf3055 100644
--- a/drivers/gpio/gpiolib-sysfs.c
+++ b/drivers/gpio/gpiolib-sysfs.c
@@ -1,31 +1,97 @@
 // SPDX-License-Identifier: GPL-2.0
-#include <linux/idr.h>
-#include <linux/mutex.h>
+
+#include <linux/bitops.h>
+#include <linux/cleanup.h>
 #include <linux/device.h>
-#include <linux/sysfs.h>
-#include <linux/gpio/consumer.h>
-#include <linux/gpio/driver.h>
+#include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/kdev_t.h>
+#include <linux/kstrtox.h>
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/printk.h>
 #include <linux/slab.h>
-#include <linux/ctype.h>
+#include <linux/string.h>
+#include <linux/srcu.h>
+#include <linux/sysfs.h>
+#include <linux/types.h>
+
+#include <linux/gpio/consumer.h>
+#include <linux/gpio/driver.h>
+
+#include <uapi/linux/gpio.h>
 
 #include "gpiolib.h"
+#include "gpiolib-sysfs.h"
+
+#if IS_ENABLED(CONFIG_GPIO_SYSFS_LEGACY)
 
+struct kernfs_node;
+
+#define GPIO_IRQF_TRIGGER_NONE		0
 #define GPIO_IRQF_TRIGGER_FALLING	BIT(0)
 #define GPIO_IRQF_TRIGGER_RISING	BIT(1)
 #define GPIO_IRQF_TRIGGER_BOTH		(GPIO_IRQF_TRIGGER_FALLING | \
 					 GPIO_IRQF_TRIGGER_RISING)
 
+enum {
+	GPIO_SYSFS_LINE_CLASS_ATTR_DIRECTION = 0,
+	GPIO_SYSFS_LINE_CLASS_ATTR_VALUE,
+	GPIO_SYSFS_LINE_CLASS_ATTR_EDGE,
+	GPIO_SYSFS_LINE_CLASS_ATTR_ACTIVE_LOW,
+	GPIO_SYSFS_LINE_CLASS_ATTR_SENTINEL,
+	GPIO_SYSFS_LINE_CLASS_ATTR_SIZE,
+};
+
+#endif /* CONFIG_GPIO_SYSFS_LEGACY */
+
+enum {
+	GPIO_SYSFS_LINE_CHIP_ATTR_DIRECTION = 0,
+	GPIO_SYSFS_LINE_CHIP_ATTR_VALUE,
+	GPIO_SYSFS_LINE_CHIP_ATTR_SENTINEL,
+	GPIO_SYSFS_LINE_CHIP_ATTR_SIZE,
+};
+
 struct gpiod_data {
+	struct list_head list;
+
 	struct gpio_desc *desc;
+	struct device *dev;
 
 	struct mutex mutex;
+#if IS_ENABLED(CONFIG_GPIO_SYSFS_LEGACY)
 	struct kernfs_node *value_kn;
 	int irq;
 	unsigned char irq_flags;
+#endif /* CONFIG_GPIO_SYSFS_LEGACY */
 
 	bool direction_can_change;
+
+	struct kobject *parent;
+	struct device_attribute dir_attr;
+	struct device_attribute val_attr;
+
+#if IS_ENABLED(CONFIG_GPIO_SYSFS_LEGACY)
+	struct device_attribute edge_attr;
+	struct device_attribute active_low_attr;
+
+	struct attribute *class_attrs[GPIO_SYSFS_LINE_CLASS_ATTR_SIZE];
+	struct attribute_group class_attr_group;
+	const struct attribute_group *class_attr_groups[2];
+#endif /* CONFIG_GPIO_SYSFS_LEGACY */
+
+	struct attribute *chip_attrs[GPIO_SYSFS_LINE_CHIP_ATTR_SIZE];
+	struct attribute_group chip_attr_group;
+	const struct attribute_group *chip_attr_groups[2];
+};
+
+struct gpiodev_data {
+	struct list_head exported_lines;
+	struct gpio_device *gdev;
+	struct device *cdev_id; /* Class device by GPIO device ID */
+#if IS_ENABLED(CONFIG_GPIO_SYSFS_LEGACY)
+	struct device *cdev_base; /* Class device by GPIO base */
+#endif /* CONFIG_GPIO_SYSFS_LEGACY */
 };
 
 /*
@@ -56,32 +122,31 @@ static DEFINE_MUTEX(sysfs_lock);
  */
 
 static ssize_t direction_show(struct device *dev,
-		struct device_attribute *attr, char *buf)
+			      struct device_attribute *attr, char *buf)
 {
-	struct gpiod_data *data = dev_get_drvdata(dev);
+	struct gpiod_data *data = container_of(attr, struct gpiod_data,
+					       dir_attr);
 	struct gpio_desc *desc = data->desc;
-	ssize_t			status;
-
-	mutex_lock(&data->mutex);
-
-	gpiod_get_direction(desc);
-	status = sprintf(buf, "%s\n",
-			test_bit(FLAG_IS_OUT, &desc->flags)
-				? "out" : "in");
+	int value;
 
-	mutex_unlock(&data->mutex);
+	scoped_guard(mutex, &data->mutex) {
+		gpiod_get_direction(desc);
+		value = !!test_bit(GPIOD_FLAG_IS_OUT, &desc->flags);
+	}
 
-	return status;
+	return sysfs_emit(buf, "%s\n", value ? "out" : "in");
 }
 
 static ssize_t direction_store(struct device *dev,
-		struct device_attribute *attr, const char *buf, size_t size)
+			       struct device_attribute *attr, const char *buf,
+			       size_t size)
 {
-	struct gpiod_data *data = dev_get_drvdata(dev);
+	struct gpiod_data *data = container_of(attr, struct gpiod_data,
+					       dir_attr);
 	struct gpio_desc *desc = data->desc;
-	ssize_t			status;
+	ssize_t status;
 
-	mutex_lock(&data->mutex);
+	guard(mutex)(&data->mutex);
 
 	if (sysfs_streq(buf, "high"))
 		status = gpiod_direction_output_raw(desc, 1);
@@ -92,65 +157,49 @@ static ssize_t direction_store(struct device *dev,
 	else
 		status = -EINVAL;
 
-	mutex_unlock(&data->mutex);
-
 	return status ? : size;
 }
-static DEVICE_ATTR_RW(direction);
 
-static ssize_t value_show(struct device *dev,
-		struct device_attribute *attr, char *buf)
+static ssize_t value_show(struct device *dev, struct device_attribute *attr,
+			  char *buf)
 {
-	struct gpiod_data *data = dev_get_drvdata(dev);
+	struct gpiod_data *data = container_of(attr, struct gpiod_data,
+					       val_attr);
 	struct gpio_desc *desc = data->desc;
-	ssize_t			status;
+	ssize_t status;
 
-	mutex_lock(&data->mutex);
+	scoped_guard(mutex, &data->mutex)
+		status = gpiod_get_value_cansleep(desc);
 
-	status = gpiod_get_value_cansleep(desc);
 	if (status < 0)
-		goto err;
-
-	buf[0] = '0' + status;
-	buf[1] = '\n';
-	status = 2;
-err:
-	mutex_unlock(&data->mutex);
+		return status;
 
-	return status;
+	return sysfs_emit(buf, "%zd\n", status);
 }
 
-static ssize_t value_store(struct device *dev,
-		struct device_attribute *attr, const char *buf, size_t size)
+static ssize_t value_store(struct device *dev, struct device_attribute *attr,
+			   const char *buf, size_t size)
 {
-	struct gpiod_data *data = dev_get_drvdata(dev);
+	struct gpiod_data *data = container_of(attr, struct gpiod_data,
+					       val_attr);
 	struct gpio_desc *desc = data->desc;
-	ssize_t status = 0;
+	ssize_t status;
+	long value;
 
-	mutex_lock(&data->mutex);
+	status = kstrtol(buf, 0, &value);
+	if (status)
+		return status;
 
-	if (!test_bit(FLAG_IS_OUT, &desc->flags)) {
-		status = -EPERM;
-	} else {
-		long		value;
-
-		if (size <= 2 && isdigit(buf[0]) &&
-		    (size == 1 || buf[1] == '\n'))
-			value = buf[0] - '0';
-		else
-			status = kstrtol(buf, 0, &value);
-		if (status == 0) {
-			gpiod_set_value_cansleep(desc, value);
-			status = size;
-		}
-	}
+	guard(mutex)(&data->mutex);
 
-	mutex_unlock(&data->mutex);
+	status = gpiod_set_value_cansleep(desc, value);
+	if (status)
+		return status;
 
-	return status;
+	return size;
 }
-static DEVICE_ATTR_PREALLOC(value, S_IWUSR | S_IRUGO, value_show, value_store);
 
+#if IS_ENABLED(CONFIG_GPIO_SYSFS_LEGACY)
 static irqreturn_t gpio_sysfs_irq(int irq, void *priv)
 {
 	struct gpiod_data *data = priv;
@@ -161,40 +210,43 @@ static irqreturn_t gpio_sysfs_irq(int irq, void *priv)
 }
 
 /* Caller holds gpiod-data mutex. */
-static int gpio_sysfs_request_irq(struct device *dev, unsigned char flags)
+static int gpio_sysfs_request_irq(struct gpiod_data *data, unsigned char flags)
 {
-	struct gpiod_data	*data = dev_get_drvdata(dev);
-	struct gpio_desc	*desc = data->desc;
-	unsigned long		irq_flags;
-	int			ret;
+	struct gpio_desc *desc = data->desc;
+	unsigned long irq_flags;
+	int ret;
+
+	CLASS(gpio_chip_guard, guard)(desc);
+	if (!guard.gc)
+		return -ENODEV;
 
 	data->irq = gpiod_to_irq(desc);
 	if (data->irq < 0)
 		return -EIO;
 
-	data->value_kn = sysfs_get_dirent(dev->kobj.sd, "value");
-	if (!data->value_kn)
-		return -ENODEV;
-
 	irq_flags = IRQF_SHARED;
-	if (flags & GPIO_IRQF_TRIGGER_FALLING)
-		irq_flags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ?
-			IRQF_TRIGGER_RISING : IRQF_TRIGGER_FALLING;
-	if (flags & GPIO_IRQF_TRIGGER_RISING)
-		irq_flags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ?
-			IRQF_TRIGGER_FALLING : IRQF_TRIGGER_RISING;
+	if (flags & GPIO_IRQF_TRIGGER_FALLING) {
+		irq_flags |= test_bit(GPIOD_FLAG_ACTIVE_LOW, &desc->flags) ?
+				IRQF_TRIGGER_RISING : IRQF_TRIGGER_FALLING;
+		set_bit(GPIOD_FLAG_EDGE_FALLING, &desc->flags);
+	}
+	if (flags & GPIO_IRQF_TRIGGER_RISING) {
+		irq_flags |= test_bit(GPIOD_FLAG_ACTIVE_LOW, &desc->flags) ?
+				IRQF_TRIGGER_FALLING : IRQF_TRIGGER_RISING;
+		set_bit(GPIOD_FLAG_EDGE_RISING, &desc->flags);
+	}
 
 	/*
 	 * FIXME: This should be done in the irq_request_resources callback
-	 *        when the irq is requested, but a few drivers currently fail
-	 *        to do so.
+	 * when the irq is requested, but a few drivers currently fail to do
+	 * so.
 	 *
-	 *        Remove this redundant call (along with the corresponding
-	 *        unlock) when those drivers have been fixed.
+	 * Remove this redundant call (along with the corresponding unlock)
+	 * when those drivers have been fixed.
 	 */
-	ret = gpiochip_lock_as_irq(desc->gdev->chip, gpio_chip_hwgpio(desc));
+	ret = gpiochip_lock_as_irq(guard.gc, gpiod_hwgpio(desc));
 	if (ret < 0)
-		goto err_put_kn;
+		goto err_clr_bits;
 
 	ret = request_any_context_irq(data->irq, gpio_sysfs_irq, irq_flags,
 				"gpiolib", data);
@@ -206,9 +258,10 @@ static int gpio_sysfs_request_irq(struct device *dev, unsigned char flags)
 	return 0;
 
 err_unlock:
-	gpiochip_unlock_as_irq(desc->gdev->chip, gpio_chip_hwgpio(desc));
-err_put_kn:
-	sysfs_put(data->value_kn);
+	gpiochip_unlock_as_irq(guard.gc, gpiod_hwgpio(desc));
+err_clr_bits:
+	clear_bit(GPIOD_FLAG_EDGE_RISING, &desc->flags);
+	clear_bit(GPIOD_FLAG_EDGE_FALLING, &desc->flags);
 
 	return ret;
 }
@@ -217,225 +270,312 @@ err_put_kn:
  * Caller holds gpiod-data mutex (unless called after class-device
  * deregistration).
  */
-static void gpio_sysfs_free_irq(struct device *dev)
+static void gpio_sysfs_free_irq(struct gpiod_data *data)
 {
-	struct gpiod_data *data = dev_get_drvdata(dev);
 	struct gpio_desc *desc = data->desc;
 
+	CLASS(gpio_chip_guard, guard)(desc);
+	if (!guard.gc)
+		return;
+
 	data->irq_flags = 0;
 	free_irq(data->irq, data);
-	gpiochip_unlock_as_irq(desc->gdev->chip, gpio_chip_hwgpio(desc));
-	sysfs_put(data->value_kn);
-}
-
-static const struct {
-	const char *name;
-	unsigned char flags;
-} trigger_types[] = {
-	{ "none",    0 },
-	{ "falling", GPIO_IRQF_TRIGGER_FALLING },
-	{ "rising",  GPIO_IRQF_TRIGGER_RISING },
-	{ "both",    GPIO_IRQF_TRIGGER_BOTH },
+	gpiochip_unlock_as_irq(guard.gc, gpiod_hwgpio(desc));
+	clear_bit(GPIOD_FLAG_EDGE_RISING, &desc->flags);
+	clear_bit(GPIOD_FLAG_EDGE_FALLING, &desc->flags);
+}
+
+static const char *const trigger_names[] = {
+	[GPIO_IRQF_TRIGGER_NONE]	= "none",
+	[GPIO_IRQF_TRIGGER_FALLING]	= "falling",
+	[GPIO_IRQF_TRIGGER_RISING]	= "rising",
+	[GPIO_IRQF_TRIGGER_BOTH]	= "both",
 };
 
-static ssize_t edge_show(struct device *dev,
-		struct device_attribute *attr, char *buf)
+static ssize_t edge_show(struct device *dev, struct device_attribute *attr,
+			 char *buf)
 {
-	struct gpiod_data *data = dev_get_drvdata(dev);
-	ssize_t	status = 0;
-	int i;
+	struct gpiod_data *data = container_of(attr, struct gpiod_data,
+					       edge_attr);
+	int flags;
 
-	mutex_lock(&data->mutex);
+	scoped_guard(mutex, &data->mutex)
+		flags = data->irq_flags;
 
-	for (i = 0; i < ARRAY_SIZE(trigger_types); i++) {
-		if (data->irq_flags == trigger_types[i].flags) {
-			status = sprintf(buf, "%s\n", trigger_types[i].name);
-			break;
-		}
-	}
-
-	mutex_unlock(&data->mutex);
+	if (flags >= ARRAY_SIZE(trigger_names))
+		return 0;
 
-	return status;
+	return sysfs_emit(buf, "%s\n", trigger_names[flags]);
 }
 
-static ssize_t edge_store(struct device *dev,
-		struct device_attribute *attr, const char *buf, size_t size)
+static ssize_t edge_store(struct device *dev, struct device_attribute *attr,
+			  const char *buf, size_t size)
 {
-	struct gpiod_data *data = dev_get_drvdata(dev);
-	unsigned char flags;
-	ssize_t	status = size;
-	int i;
+	struct gpiod_data *data = container_of(attr, struct gpiod_data,
+					       edge_attr);
+	ssize_t status = size;
+	int flags;
 
-	for (i = 0; i < ARRAY_SIZE(trigger_types); i++) {
-		if (sysfs_streq(trigger_types[i].name, buf))
-			break;
-	}
+	flags = sysfs_match_string(trigger_names, buf);
+	if (flags < 0)
+		return flags;
 
-	if (i == ARRAY_SIZE(trigger_types))
-		return -EINVAL;
+	guard(mutex)(&data->mutex);
 
-	flags = trigger_types[i].flags;
-
-	mutex_lock(&data->mutex);
-
-	if (flags == data->irq_flags) {
-		status = size;
-		goto out_unlock;
-	}
+	if (flags == data->irq_flags)
+		return size;
 
 	if (data->irq_flags)
-		gpio_sysfs_free_irq(dev);
+		gpio_sysfs_free_irq(data);
 
-	if (flags) {
-		status = gpio_sysfs_request_irq(dev, flags);
-		if (!status)
-			status = size;
-	}
+	if (!flags)
+		return size;
 
-out_unlock:
-	mutex_unlock(&data->mutex);
+	status = gpio_sysfs_request_irq(data, flags);
+	if (status)
+		return status;
 
-	return status;
+	gpiod_line_state_notify(data->desc, GPIO_V2_LINE_CHANGED_CONFIG);
+
+	return size;
 }
-static DEVICE_ATTR_RW(edge);
 
 /* Caller holds gpiod-data mutex. */
-static int gpio_sysfs_set_active_low(struct device *dev, int value)
+static int gpio_sysfs_set_active_low(struct gpiod_data *data, int value)
 {
-	struct gpiod_data	*data = dev_get_drvdata(dev);
-	struct gpio_desc	*desc = data->desc;
-	int			status = 0;
-	unsigned int		flags = data->irq_flags;
+	unsigned int flags = data->irq_flags;
+	struct gpio_desc *desc = data->desc;
+	int status = 0;
 
-	if (!!test_bit(FLAG_ACTIVE_LOW, &desc->flags) == !!value)
+	if (!!test_bit(GPIOD_FLAG_ACTIVE_LOW, &desc->flags) == !!value)
 		return 0;
 
-	if (value)
-		set_bit(FLAG_ACTIVE_LOW, &desc->flags);
-	else
-		clear_bit(FLAG_ACTIVE_LOW, &desc->flags);
+	assign_bit(GPIOD_FLAG_ACTIVE_LOW, &desc->flags, value);
 
 	/* reconfigure poll(2) support if enabled on one edge only */
 	if (flags == GPIO_IRQF_TRIGGER_FALLING ||
-					flags == GPIO_IRQF_TRIGGER_RISING) {
-		gpio_sysfs_free_irq(dev);
-		status = gpio_sysfs_request_irq(dev, flags);
+	    flags == GPIO_IRQF_TRIGGER_RISING) {
+		gpio_sysfs_free_irq(data);
+		status = gpio_sysfs_request_irq(data, flags);
 	}
 
+	gpiod_line_state_notify(desc, GPIO_V2_LINE_CHANGED_CONFIG);
+
 	return status;
 }
 
 static ssize_t active_low_show(struct device *dev,
-		struct device_attribute *attr, char *buf)
+			       struct device_attribute *attr, char *buf)
 {
-	struct gpiod_data *data = dev_get_drvdata(dev);
+	struct gpiod_data *data = container_of(attr, struct gpiod_data,
+					       active_low_attr);
 	struct gpio_desc *desc = data->desc;
-	ssize_t			status;
-
-	mutex_lock(&data->mutex);
+	int value;
 
-	status = sprintf(buf, "%d\n",
-				!!test_bit(FLAG_ACTIVE_LOW, &desc->flags));
+	scoped_guard(mutex, &data->mutex)
+		value = !!test_bit(GPIOD_FLAG_ACTIVE_LOW, &desc->flags);
 
-	mutex_unlock(&data->mutex);
-
-	return status;
+	return sysfs_emit(buf, "%d\n", value);
 }
 
 static ssize_t active_low_store(struct device *dev,
-		struct device_attribute *attr, const char *buf, size_t size)
+				struct device_attribute *attr,
+				const char *buf, size_t size)
 {
-	struct gpiod_data	*data = dev_get_drvdata(dev);
-	ssize_t			status;
-	long			value;
-
-	mutex_lock(&data->mutex);
+	struct gpiod_data *data = container_of(attr, struct gpiod_data,
+					       active_low_attr);
+	ssize_t status;
+	long value;
 
 	status = kstrtol(buf, 0, &value);
-	if (status == 0)
-		status = gpio_sysfs_set_active_low(dev, value);
+	if (status)
+		return status;
 
-	mutex_unlock(&data->mutex);
+	guard(mutex)(&data->mutex);
 
-	return status ? : size;
+	return gpio_sysfs_set_active_low(data, value) ?: size;
 }
-static DEVICE_ATTR_RW(active_low);
+#endif /* CONFIG_GPIO_SYSFS_LEGACY */
 
 static umode_t gpio_is_visible(struct kobject *kobj, struct attribute *attr,
 			       int n)
 {
-	struct device *dev = container_of(kobj, struct device, kobj);
-	struct gpiod_data *data = dev_get_drvdata(dev);
-	struct gpio_desc *desc = data->desc;
+	struct device_attribute *dev_attr = container_of(attr,
+						struct device_attribute, attr);
 	umode_t mode = attr->mode;
-	bool show_direction = data->direction_can_change;
+	struct gpiod_data *data;
 
-	if (attr == &dev_attr_direction.attr) {
-		if (!show_direction)
+	if (strcmp(attr->name, "direction") == 0) {
+		data = container_of(dev_attr, struct gpiod_data, dir_attr);
+
+		if (!data->direction_can_change)
 			mode = 0;
-	} else if (attr == &dev_attr_edge.attr) {
-		if (gpiod_to_irq(desc) < 0)
+#if IS_ENABLED(CONFIG_GPIO_SYSFS_LEGACY)
+	} else if (strcmp(attr->name, "edge") == 0) {
+		data = container_of(dev_attr, struct gpiod_data, edge_attr);
+
+		if (gpiod_to_irq(data->desc) < 0)
 			mode = 0;
-		if (!show_direction && test_bit(FLAG_IS_OUT, &desc->flags))
+
+		if (!data->direction_can_change &&
+		    test_bit(GPIOD_FLAG_IS_OUT, &data->desc->flags))
 			mode = 0;
+#endif /* CONFIG_GPIO_SYSFS_LEGACY */
 	}
 
 	return mode;
 }
 
-static struct attribute *gpio_attrs[] = {
-	&dev_attr_direction.attr,
-	&dev_attr_edge.attr,
-	&dev_attr_value.attr,
-	&dev_attr_active_low.attr,
-	NULL,
-};
-
-static const struct attribute_group gpio_group = {
-	.attrs = gpio_attrs,
-	.is_visible = gpio_is_visible,
-};
-
-static const struct attribute_group *gpio_groups[] = {
-	&gpio_group,
-	NULL
-};
-
 /*
  * /sys/class/gpio/gpiochipN/
  *   /base ... matching gpio_chip.base (N)
  *   /label ... matching gpio_chip.label
  *   /ngpio ... matching gpio_chip.ngpio
+ *
+ * AND
+ *
+ * /sys/class/gpio/chipX/
+ *   /export ... export GPIO at given offset
+ *   /unexport ... unexport GPIO at given offset
+ *   /label ... matching gpio_chip.label
+ *   /ngpio ... matching gpio_chip.ngpio
  */
 
-static ssize_t base_show(struct device *dev,
-			       struct device_attribute *attr, char *buf)
+#if IS_ENABLED(CONFIG_GPIO_SYSFS_LEGACY)
+static ssize_t base_show(struct device *dev, struct device_attribute *attr,
+			 char *buf)
 {
-	const struct gpio_chip	*chip = dev_get_drvdata(dev);
+	const struct gpiodev_data *data = dev_get_drvdata(dev);
 
-	return sprintf(buf, "%d\n", chip->base);
+	return sysfs_emit(buf, "%u\n", data->gdev->base);
 }
 static DEVICE_ATTR_RO(base);
+#endif /* CONFIG_GPIO_SYSFS_LEGACY */
 
-static ssize_t label_show(struct device *dev,
-			       struct device_attribute *attr, char *buf)
+static ssize_t label_show(struct device *dev, struct device_attribute *attr,
+			  char *buf)
 {
-	const struct gpio_chip	*chip = dev_get_drvdata(dev);
+	const struct gpiodev_data *data = dev_get_drvdata(dev);
 
-	return sprintf(buf, "%s\n", chip->label ? : "");
+	return sysfs_emit(buf, "%s\n", data->gdev->label);
 }
 static DEVICE_ATTR_RO(label);
 
-static ssize_t ngpio_show(struct device *dev,
-			       struct device_attribute *attr, char *buf)
+static ssize_t ngpio_show(struct device *dev, struct device_attribute *attr,
+			  char *buf)
 {
-	const struct gpio_chip	*chip = dev_get_drvdata(dev);
+	const struct gpiodev_data *data = dev_get_drvdata(dev);
 
-	return sprintf(buf, "%u\n", chip->ngpio);
+	return sysfs_emit(buf, "%u\n", data->gdev->ngpio);
 }
 static DEVICE_ATTR_RO(ngpio);
 
+static int export_gpio_desc(struct gpio_desc *desc)
+{
+	int offset, ret;
+
+	CLASS(gpio_chip_guard, guard)(desc);
+	if (!guard.gc)
+		return -ENODEV;
+
+	offset = gpiod_hwgpio(desc);
+	if (!gpiochip_line_is_valid(guard.gc, offset)) {
+		pr_debug_ratelimited("%s: GPIO %d masked\n", __func__,
+				     gpiod_hwgpio(desc));
+		return -EINVAL;
+	}
+
+	/*
+	 * No extra locking here; GPIOD_FLAG_SYSFS just signifies that the
+	 * request and export were done by on behalf of userspace, so
+	 * they may be undone on its behalf too.
+	 */
+
+	ret = gpiod_request_user(desc, "sysfs");
+	if (ret)
+		return ret;
+
+	ret = gpiod_set_transitory(desc, false);
+	if (ret) {
+		gpiod_free(desc);
+		return ret;
+	}
+
+	ret = gpiod_export(desc, true);
+	if (ret < 0) {
+		gpiod_free(desc);
+	} else {
+		set_bit(GPIOD_FLAG_SYSFS, &desc->flags);
+		gpiod_line_state_notify(desc, GPIO_V2_LINE_CHANGED_REQUESTED);
+	}
+
+	return ret;
+}
+
+static int unexport_gpio_desc(struct gpio_desc *desc)
+{
+	/*
+	 * No extra locking here; GPIOD_FLAG_SYSFS just signifies that the
+	 * request and export were done by on behalf of userspace, so
+	 * they may be undone on its behalf too.
+	 */
+	if (!test_and_clear_bit(GPIOD_FLAG_SYSFS, &desc->flags))
+		return -EINVAL;
+
+	gpiod_unexport(desc);
+	gpiod_free(desc);
+
+	return 0;
+}
+
+static ssize_t do_chip_export_store(struct device *dev,
+				    struct device_attribute *attr,
+				    const char *buf, ssize_t size,
+				    int (*handler)(struct gpio_desc *desc))
+{
+	struct gpiodev_data *data = dev_get_drvdata(dev);
+	struct gpio_device *gdev = data->gdev;
+	struct gpio_desc *desc;
+	unsigned int gpio;
+	int ret;
+
+	ret = kstrtouint(buf, 0, &gpio);
+	if (ret)
+		return ret;
+
+	desc = gpio_device_get_desc(gdev, gpio);
+	if (IS_ERR(desc))
+		return PTR_ERR(desc);
+
+	ret = handler(desc);
+	if (ret)
+		return ret;
+
+	return size;
+}
+
+static ssize_t chip_export_store(struct device *dev,
+				 struct device_attribute *attr,
+				 const char *buf, size_t size)
+{
+	return do_chip_export_store(dev, attr, buf, size, export_gpio_desc);
+}
+
+static struct device_attribute dev_attr_export = __ATTR(export, 0200, NULL,
+							chip_export_store);
+
+static ssize_t chip_unexport_store(struct device *dev,
+				   struct device_attribute *attr,
+				   const char *buf, size_t size)
+{
+	return do_chip_export_store(dev, attr, buf, size, unexport_gpio_desc);
+}
+
+static struct device_attribute dev_attr_unexport = __ATTR(unexport, 0200,
+							  NULL,
+							  chip_unexport_store);
+
+#if IS_ENABLED(CONFIG_GPIO_SYSFS_LEGACY)
 static struct attribute *gpiochip_attrs[] = {
 	&dev_attr_base.attr,
 	&dev_attr_label.attr,
@@ -443,90 +583,70 @@ static struct attribute *gpiochip_attrs[] = {
 	NULL,
 };
 ATTRIBUTE_GROUPS(gpiochip);
+#endif /* CONFIG_GPIO_SYSFS_LEGACY */
+
+static struct attribute *gpiochip_ext_attrs[] = {
+	&dev_attr_label.attr,
+	&dev_attr_ngpio.attr,
+	&dev_attr_export.attr,
+	&dev_attr_unexport.attr,
+	NULL
+};
+ATTRIBUTE_GROUPS(gpiochip_ext);
 
+#if IS_ENABLED(CONFIG_GPIO_SYSFS_LEGACY)
 /*
  * /sys/class/gpio/export ... write-only
  *	integer N ... number of GPIO to export (full access)
  * /sys/class/gpio/unexport ... write-only
  *	integer N ... number of GPIO to unexport
  */
-static ssize_t export_store(struct class *class,
-				struct class_attribute *attr,
-				const char *buf, size_t len)
+static ssize_t export_store(const struct class *class,
+			    const struct class_attribute *attr,
+			    const char *buf, size_t len)
 {
-	long			gpio;
-	struct gpio_desc	*desc;
-	int			status;
+	struct gpio_desc *desc;
+	int status;
+	long gpio;
 
 	status = kstrtol(buf, 0, &gpio);
-	if (status < 0)
-		goto done;
+	if (status)
+		return status;
 
 	desc = gpio_to_desc(gpio);
 	/* reject invalid GPIOs */
 	if (!desc) {
-		pr_warn("%s: invalid GPIO %ld\n", __func__, gpio);
+		pr_debug_ratelimited("%s: invalid GPIO %ld\n", __func__, gpio);
 		return -EINVAL;
 	}
 
-	/* No extra locking here; FLAG_SYSFS just signifies that the
-	 * request and export were done by on behalf of userspace, so
-	 * they may be undone on its behalf too.
-	 */
-
-	status = gpiod_request(desc, "sysfs");
-	if (status < 0) {
-		if (status == -EPROBE_DEFER)
-			status = -ENODEV;
-		goto done;
-	}
-
-	status = gpiod_set_transitory(desc, false);
-	if (!status) {
-		status = gpiod_export(desc, true);
-		if (status < 0)
-			gpiod_free(desc);
-		else
-			set_bit(FLAG_SYSFS, &desc->flags);
-	}
-
-done:
+	status = export_gpio_desc(desc);
 	if (status)
 		pr_debug("%s: status %d\n", __func__, status);
 	return status ? : len;
 }
 static CLASS_ATTR_WO(export);
 
-static ssize_t unexport_store(struct class *class,
-				struct class_attribute *attr,
-				const char *buf, size_t len)
+static ssize_t unexport_store(const struct class *class,
+			      const struct class_attribute *attr,
+			      const char *buf, size_t len)
 {
-	long			gpio;
-	struct gpio_desc	*desc;
-	int			status;
+	struct gpio_desc *desc;
+	int status;
+	long gpio;
 
 	status = kstrtol(buf, 0, &gpio);
 	if (status < 0)
-		goto done;
+		return status;
 
 	desc = gpio_to_desc(gpio);
-	/* reject bogus commands (gpio_unexport ignores them) */
+	/* reject bogus commands (gpiod_unexport() ignores them) */
 	if (!desc) {
-		pr_warn("%s: invalid GPIO %ld\n", __func__, gpio);
+		pr_debug_ratelimited("%s: invalid GPIO %ld\n", __func__, gpio);
 		return -EINVAL;
 	}
 
-	status = -EINVAL;
-
-	/* No extra locking here; FLAG_SYSFS just signifies that the
-	 * request and export were done by on behalf of userspace, so
-	 * they may be undone on its behalf too.
-	 */
-	if (test_and_clear_bit(FLAG_SYSFS, &desc->flags)) {
-		status = 0;
-		gpiod_free(desc);
-	}
-done:
+	status = unexport_gpio_desc(desc);
 	if (status)
 		pr_debug("%s: status %d\n", __func__, status);
 	return status ? : len;
@@ -539,14 +659,54 @@ static struct attribute *gpio_class_attrs[] = {
 	NULL,
 };
 ATTRIBUTE_GROUPS(gpio_class);
+#endif /* CONFIG_GPIO_SYSFS_LEGACY */
 
-static struct class gpio_class = {
+static const struct class gpio_class = {
 	.name =		"gpio",
-	.owner =	THIS_MODULE,
+#if IS_ENABLED(CONFIG_GPIO_SYSFS_LEGACY)
+	.class_groups =	gpio_class_groups,
+#endif /* CONFIG_GPIO_SYSFS_LEGACY */
+};
 
-	.class_groups = gpio_class_groups,
+static int match_gdev(struct device *dev, const void *desc)
+{
+	struct gpiodev_data *data = dev_get_drvdata(dev);
+	const struct gpio_device *gdev = desc;
+
+	return data && data->gdev == gdev;
+}
+
+static struct gpiodev_data *
+gdev_get_data(struct gpio_device *gdev) __must_hold(&sysfs_lock)
+{
+	/*
+	 * Find the first device in GPIO class that matches. Whether that's
+	 * the one indexed by GPIO base or device ID doesn't matter, it has
+	 * the same address set as driver data.
+	 */
+	struct device *cdev __free(put_device) = class_find_device(&gpio_class,
+								   NULL, gdev,
+								   match_gdev);
+	if (!cdev)
+		return NULL;
+
+	return dev_get_drvdata(cdev);
 };
 
+static void gpiod_attr_init(struct device_attribute *dev_attr, const char *name,
+			    ssize_t (*show)(struct device *dev,
+					    struct device_attribute *attr,
+					    char *buf),
+			    ssize_t (*store)(struct device *dev,
+					     struct device_attribute *attr,
+					     const char *buf, size_t count))
+{
+	sysfs_attr_init(&dev_attr->attr);
+	dev_attr->attr.name = name;
+	dev_attr->attr.mode = 0644;
+	dev_attr->show = show;
+	dev_attr->store = store;
+}
 
 /**
  * gpiod_export - export a GPIO through sysfs
@@ -561,21 +721,20 @@ static struct class gpio_class = {
  * will see "direction" sysfs attribute which may be used to change
  * the gpio's direction.  A "value" attribute will always be provided.
  *
- * Returns zero on success, else an error.
+ * Returns:
+ * 0 on success, or negative errno on failure.
  */
 int gpiod_export(struct gpio_desc *desc, bool direction_may_change)
 {
-	struct gpio_chip	*chip;
-	struct gpio_device	*gdev;
-	struct gpiod_data	*data;
-	unsigned long		flags;
-	int			status;
-	const char		*ioname = NULL;
-	struct device		*dev;
-	int			offset;
+	char *path __free(kfree) = NULL;
+	struct gpiodev_data *gdev_data;
+	struct gpiod_data *desc_data;
+	struct gpio_device *gdev;
+	struct attribute **attrs;
+	int status;
 
 	/* can't export until sysfs is available ... */
-	if (!gpio_class.p) {
+	if (!class_is_registered(&gpio_class)) {
 		pr_debug("%s: called too early!\n", __func__);
 		return -ENOENT;
 	}
@@ -585,75 +744,142 @@ int gpiod_export(struct gpio_desc *desc, bool direction_may_change)
 		return -EINVAL;
 	}
 
-	gdev = desc->gdev;
-	chip = gdev->chip;
+	CLASS(gpio_chip_guard, guard)(desc);
+	if (!guard.gc)
+		return -ENODEV;
 
-	mutex_lock(&sysfs_lock);
+	if (test_and_set_bit(GPIOD_FLAG_EXPORT, &desc->flags))
+		return -EPERM;
 
-	/* check if chip is being removed */
-	if (!chip || !gdev->mockdev) {
-		status = -ENODEV;
-		goto err_unlock;
-	}
+	gdev = desc->gdev;
 
-	spin_lock_irqsave(&gpio_lock, flags);
-	if (!test_bit(FLAG_REQUESTED, &desc->flags) ||
-	     test_bit(FLAG_EXPORT, &desc->flags)) {
-		spin_unlock_irqrestore(&gpio_lock, flags);
-		gpiod_dbg(desc, "%s: unavailable (requested=%d, exported=%d)\n",
-				__func__,
-				test_bit(FLAG_REQUESTED, &desc->flags),
-				test_bit(FLAG_EXPORT, &desc->flags));
+	guard(mutex)(&sysfs_lock);
+
+	if (!test_bit(GPIOD_FLAG_REQUESTED, &desc->flags)) {
+		gpiod_dbg(desc, "%s: unavailable (not requested)\n", __func__);
 		status = -EPERM;
-		goto err_unlock;
+		goto err_clear_bit;
 	}
-	spin_unlock_irqrestore(&gpio_lock, flags);
 
-	data = kzalloc(sizeof(*data), GFP_KERNEL);
-	if (!data) {
+	desc_data = kzalloc(sizeof(*desc_data), GFP_KERNEL);
+	if (!desc_data) {
 		status = -ENOMEM;
-		goto err_unlock;
+		goto err_clear_bit;
 	}
 
-	data->desc = desc;
-	mutex_init(&data->mutex);
-	if (chip->direction_input && chip->direction_output)
-		data->direction_can_change = direction_may_change;
+	desc_data->desc = desc;
+	mutex_init(&desc_data->mutex);
+	if (guard.gc->direction_input && guard.gc->direction_output)
+		desc_data->direction_can_change = direction_may_change;
 	else
-		data->direction_can_change = false;
-
-	offset = gpio_chip_hwgpio(desc);
-	if (chip->names && chip->names[offset])
-		ioname = chip->names[offset];
-
-	dev = device_create_with_groups(&gpio_class, &gdev->dev,
-					MKDEV(0, 0), data, gpio_groups,
-					ioname ? ioname : "gpio%u",
-					desc_to_gpio(desc));
-	if (IS_ERR(dev)) {
-		status = PTR_ERR(dev);
+		desc_data->direction_can_change = false;
+
+	gpiod_attr_init(&desc_data->dir_attr, "direction",
+			direction_show, direction_store);
+	gpiod_attr_init(&desc_data->val_attr, "value", value_show, value_store);
+
+#if IS_ENABLED(CONFIG_GPIO_SYSFS_LEGACY)
+	gpiod_attr_init(&desc_data->edge_attr, "edge", edge_show, edge_store);
+	gpiod_attr_init(&desc_data->active_low_attr, "active_low",
+			active_low_show, active_low_store);
+
+	attrs = desc_data->class_attrs;
+	desc_data->class_attr_group.is_visible = gpio_is_visible;
+	attrs[GPIO_SYSFS_LINE_CLASS_ATTR_DIRECTION] = &desc_data->dir_attr.attr;
+	attrs[GPIO_SYSFS_LINE_CLASS_ATTR_VALUE] = &desc_data->val_attr.attr;
+	attrs[GPIO_SYSFS_LINE_CLASS_ATTR_EDGE] = &desc_data->edge_attr.attr;
+	attrs[GPIO_SYSFS_LINE_CLASS_ATTR_ACTIVE_LOW] = &desc_data->active_low_attr.attr;
+
+	desc_data->class_attr_group.attrs = desc_data->class_attrs;
+	desc_data->class_attr_groups[0] = &desc_data->class_attr_group;
+
+	/*
+	 * Note: we need to continue passing desc_data here as there's still
+	 * at least one known user of gpiod_export_link() in the tree. This
+	 * function still uses class_find_device() internally.
+	 */
+	desc_data->dev = device_create_with_groups(&gpio_class, &gdev->dev,
+						   MKDEV(0, 0), desc_data,
+						   desc_data->class_attr_groups,
+						   "gpio%u",
+						   desc_to_gpio(desc));
+	if (IS_ERR(desc_data->dev)) {
+		status = PTR_ERR(desc_data->dev);
 		goto err_free_data;
 	}
 
-	set_bit(FLAG_EXPORT, &desc->flags);
-	mutex_unlock(&sysfs_lock);
+	desc_data->value_kn = sysfs_get_dirent(desc_data->dev->kobj.sd,
+						       "value");
+	if (!desc_data->value_kn) {
+		status = -ENODEV;
+		goto err_unregister_device;
+	}
+#endif /* CONFIG_GPIO_SYSFS_LEGACY */
+
+	gdev_data = gdev_get_data(gdev);
+	if (!gdev_data) {
+		status = -ENODEV;
+		goto err_put_dirent;
+	}
+
+	desc_data->chip_attr_group.name = kasprintf(GFP_KERNEL, "gpio%u",
+						    gpiod_hwgpio(desc));
+	if (!desc_data->chip_attr_group.name) {
+		status = -ENOMEM;
+		goto err_put_dirent;
+	}
+
+	attrs = desc_data->chip_attrs;
+	desc_data->chip_attr_group.is_visible = gpio_is_visible;
+	attrs[GPIO_SYSFS_LINE_CHIP_ATTR_DIRECTION] = &desc_data->dir_attr.attr;
+	attrs[GPIO_SYSFS_LINE_CHIP_ATTR_VALUE] = &desc_data->val_attr.attr;
+
+	desc_data->chip_attr_group.attrs = attrs;
+	desc_data->chip_attr_groups[0] = &desc_data->chip_attr_group;
+
+	desc_data->parent = &gdev_data->cdev_id->kobj;
+	status = sysfs_create_groups(desc_data->parent,
+				     desc_data->chip_attr_groups);
+	if (status)
+		goto err_free_name;
+
+	path = kasprintf(GFP_KERNEL, "gpio%u/value", gpiod_hwgpio(desc));
+	if (!path) {
+		status = -ENOMEM;
+		goto err_remove_groups;
+	}
+
+	list_add(&desc_data->list, &gdev_data->exported_lines);
+
 	return 0;
 
+err_remove_groups:
+	sysfs_remove_groups(desc_data->parent, desc_data->chip_attr_groups);
+err_free_name:
+	kfree(desc_data->chip_attr_group.name);
+err_put_dirent:
+#if IS_ENABLED(CONFIG_GPIO_SYSFS_LEGACY)
+	sysfs_put(desc_data->value_kn);
+err_unregister_device:
+	device_unregister(desc_data->dev);
 err_free_data:
-	kfree(data);
-err_unlock:
-	mutex_unlock(&sysfs_lock);
+#endif /* CONFIG_GPIO_SYSFS_LEGACY */
+	kfree(desc_data);
+err_clear_bit:
+	clear_bit(GPIOD_FLAG_EXPORT, &desc->flags);
 	gpiod_dbg(desc, "%s: status %d\n", __func__, status);
 	return status;
 }
 EXPORT_SYMBOL_GPL(gpiod_export);
 
+#if IS_ENABLED(CONFIG_GPIO_SYSFS_LEGACY)
 static int match_export(struct device *dev, const void *desc)
 {
 	struct gpiod_data *data = dev_get_drvdata(dev);
 
-	return data->desc == desc;
+	return gpiod_is_equal(data->desc, desc);
 }
+#endif /* CONFIG_GPIO_SYSFS_LEGACY */
 
 /**
  * gpiod_export_link - create a sysfs link to an exported GPIO node
@@ -664,11 +890,13 @@ static int match_export(struct device *dev, const void *desc)
  * Set up a symlink from /sys/.../dev/name to /sys/class/gpio/gpioN
  * node. Caller is responsible for unlinking.
  *
- * Returns zero on success, else an error.
+ * Returns:
+ * 0 on success, or negative errno on failure.
  */
 int gpiod_export_link(struct device *dev, const char *name,
 		      struct gpio_desc *desc)
 {
+#if IS_ENABLED(CONFIG_GPIO_SYSFS_LEGACY)
 	struct device *cdev;
 	int ret;
 
@@ -685,6 +913,9 @@ int gpiod_export_link(struct device *dev, const char *name,
 	put_device(cdev);
 
 	return ret;
+#else
+	return -EOPNOTSUPP;
+#endif /* CONFIG_GPIO_SYSFS_LEGACY */
 }
 EXPORT_SYMBOL_GPL(gpiod_export_link);
 
@@ -696,52 +927,63 @@ EXPORT_SYMBOL_GPL(gpiod_export_link);
  */
 void gpiod_unexport(struct gpio_desc *desc)
 {
-	struct gpiod_data *data;
-	struct device *dev;
+	struct gpiod_data *tmp, *desc_data = NULL;
+	struct gpiodev_data *gdev_data;
+	struct gpio_device *gdev;
 
 	if (!desc) {
 		pr_warn("%s: invalid GPIO\n", __func__);
 		return;
 	}
 
-	mutex_lock(&sysfs_lock);
+	scoped_guard(mutex, &sysfs_lock) {
+		if (!test_bit(GPIOD_FLAG_EXPORT, &desc->flags))
+			return;
 
-	if (!test_bit(FLAG_EXPORT, &desc->flags))
-		goto err_unlock;
-
-	dev = class_find_device(&gpio_class, NULL, desc, match_export);
-	if (!dev)
-		goto err_unlock;
-
-	data = dev_get_drvdata(dev);
+		gdev = gpiod_to_gpio_device(desc);
+		gdev_data = gdev_get_data(gdev);
+		if (!gdev_data)
+			return;
 
-	clear_bit(FLAG_EXPORT, &desc->flags);
-
-	device_unregister(dev);
+		list_for_each_entry(tmp, &gdev_data->exported_lines, list) {
+			if (gpiod_is_equal(desc, tmp->desc)) {
+				desc_data = tmp;
+				break;
+			}
+		}
 
-	/*
-	 * Release irq after deregistration to prevent race with edge_store.
-	 */
-	if (data->irq_flags)
-		gpio_sysfs_free_irq(dev);
+		if (!desc_data)
+			return;
 
-	mutex_unlock(&sysfs_lock);
+		list_del(&desc_data->list);
+		clear_bit(GPIOD_FLAG_EXPORT, &desc->flags);
+#if IS_ENABLED(CONFIG_GPIO_SYSFS_LEGACY)
+		sysfs_put(desc_data->value_kn);
+		device_unregister(desc_data->dev);
 
-	put_device(dev);
-	kfree(data);
+		/*
+		 * Release irq after deregistration to prevent race with
+		 * edge_store.
+		 */
+		if (desc_data->irq_flags)
+			gpio_sysfs_free_irq(desc_data);
+#endif /* CONFIG_GPIO_SYSFS_LEGACY */
 
-	return;
+		sysfs_remove_groups(desc_data->parent,
+				    desc_data->chip_attr_groups);
+	}
 
-err_unlock:
-	mutex_unlock(&sysfs_lock);
+	mutex_destroy(&desc_data->mutex);
+	kfree(desc_data);
 }
 EXPORT_SYMBOL_GPL(gpiod_unexport);
 
 int gpiochip_sysfs_register(struct gpio_device *gdev)
 {
-	struct device	*dev;
-	struct device	*parent;
-	struct gpio_chip *chip = gdev->chip;
+	struct gpiodev_data *data;
+	struct gpio_chip *chip;
+	struct device *parent;
+	int err;
 
 	/*
 	 * Many systems add gpio chips for SOC support very early,
@@ -749,9 +991,15 @@ int gpiochip_sysfs_register(struct gpio_device *gdev)
 	 * register later, in gpiolib_sysfs_init() ... here we just
 	 * verify that _some_ field of gpio_class got initialized.
 	 */
-	if (!gpio_class.p)
+	if (!class_is_registered(&gpio_class))
 		return 0;
 
+	guard(srcu)(&gdev->srcu);
+
+	chip = srcu_dereference(gdev->chip, &gdev->srcu);
+	if (!chip)
+		return -ENODEV;
+
 	/*
 	 * For sysfs backward compatibility we need to preserve this
 	 * preferred parenting to the gpio_chip parent field, if set.
@@ -761,50 +1009,96 @@ int gpiochip_sysfs_register(struct gpio_device *gdev)
 	else
 		parent = &gdev->dev;
 
-	/* use chip->base for the ID; it's already known to be unique */
-	dev = device_create_with_groups(&gpio_class, parent,
-					MKDEV(0, 0),
-					chip, gpiochip_groups,
-					"gpiochip%d", chip->base);
-	if (IS_ERR(dev))
-		return PTR_ERR(dev);
+	data = kmalloc(sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
 
-	mutex_lock(&sysfs_lock);
-	gdev->mockdev = dev;
-	mutex_unlock(&sysfs_lock);
+	data->gdev = gdev;
+	INIT_LIST_HEAD(&data->exported_lines);
+
+	guard(mutex)(&sysfs_lock);
+
+#if IS_ENABLED(CONFIG_GPIO_SYSFS_LEGACY)
+	/* use chip->base for the ID; it's already known to be unique */
+	data->cdev_base = device_create_with_groups(&gpio_class, parent,
+						    MKDEV(0, 0), data,
+						    gpiochip_groups,
+						    GPIOCHIP_NAME "%d",
+						    chip->base);
+	if (IS_ERR(data->cdev_base)) {
+		err = PTR_ERR(data->cdev_base);
+		kfree(data);
+		return err;
+	}
+#endif /* CONFIG_GPIO_SYSFS_LEGACY */
+
+	data->cdev_id = device_create_with_groups(&gpio_class, parent,
+						  MKDEV(0, 0), data,
+						  gpiochip_ext_groups,
+						  "chip%d", gdev->id);
+	if (IS_ERR(data->cdev_id)) {
+#if IS_ENABLED(CONFIG_GPIO_SYSFS_LEGACY)
+		device_unregister(data->cdev_base);
+#endif /* CONFIG_GPIO_SYSFS_LEGACY */
+		err = PTR_ERR(data->cdev_id);
+		kfree(data);
+		return err;
+	}
 
 	return 0;
 }
 
 void gpiochip_sysfs_unregister(struct gpio_device *gdev)
 {
+	struct gpiodev_data *data;
 	struct gpio_desc *desc;
-	struct gpio_chip *chip = gdev->chip;
-	unsigned int i;
-
-	if (!gdev->mockdev)
-		return;
+	struct gpio_chip *chip;
+
+	scoped_guard(mutex, &sysfs_lock) {
+		data = gdev_get_data(gdev);
+		if (!data)
+			return;
+
+#if IS_ENABLED(CONFIG_GPIO_SYSFS_LEGACY)
+		device_unregister(data->cdev_base);
+#endif /* CONFIG_GPIO_SYSFS_LEGACY */
+		device_unregister(data->cdev_id);
+		kfree(data);
+	}
 
-	device_unregister(gdev->mockdev);
+	guard(srcu)(&gdev->srcu);
 
-	/* prevent further gpiod exports */
-	mutex_lock(&sysfs_lock);
-	gdev->mockdev = NULL;
-	mutex_unlock(&sysfs_lock);
+	chip = srcu_dereference(gdev->chip, &gdev->srcu);
+	if (!chip)
+		return;
 
 	/* unregister gpiod class devices owned by sysfs */
-	for (i = 0; i < chip->ngpio; i++) {
-		desc = &gdev->descs[i];
-		if (test_and_clear_bit(FLAG_SYSFS, &desc->flags))
-			gpiod_free(desc);
+	for_each_gpio_desc_with_flag(chip, desc, GPIOD_FLAG_SYSFS) {
+		gpiod_unexport(desc);
+		gpiod_free(desc);
 	}
 }
 
+/*
+ * We're not really looking for a device - we just want to iterate over the
+ * list and call this callback for each GPIO device. This is why this function
+ * always returns 0.
+ */
+static int gpiofind_sysfs_register(struct gpio_chip *gc, const void *data)
+{
+	struct gpio_device *gdev = gc->gpiodev;
+	int ret;
+
+	ret = gpiochip_sysfs_register(gdev);
+	if (ret)
+		gpiochip_err(gc, "failed to register the sysfs entry: %d\n", ret);
+
+	return 0;
+}
+
 static int __init gpiolib_sysfs_init(void)
 {
-	int		status;
-	unsigned long	flags;
-	struct gpio_device *gdev;
+	int status;
 
 	status = class_register(&gpio_class);
 	if (status < 0)
@@ -814,28 +1108,10 @@ static int __init gpiolib_sysfs_init(void)
 	 * early (e.g. before the class_register above was called).
 	 *
 	 * We run before arch_initcall() so chip->dev nodes can have
-	 * registered, and so arch_initcall() can always gpio_export().
+	 * registered, and so arch_initcall() can always gpiod_export().
 	 */
-	spin_lock_irqsave(&gpio_lock, flags);
-	list_for_each_entry(gdev, &gpio_devices, list) {
-		if (gdev->mockdev)
-			continue;
-
-		/*
-		 * TODO we yield gpio_lock here because
-		 * gpiochip_sysfs_register() acquires a mutex. This is unsafe
-		 * and needs to be fixed.
-		 *
-		 * Also it would be nice to use gpiochip_find() here so we
-		 * can keep gpio_chips local to gpiolib.c, but the yield of
-		 * gpio_lock prevents us from doing this.
-		 */
-		spin_unlock_irqrestore(&gpio_lock, flags);
-		status = gpiochip_sysfs_register(gdev);
-		spin_lock_irqsave(&gpio_lock, flags);
-	}
-	spin_unlock_irqrestore(&gpio_lock, flags);
+	(void)gpio_device_find(NULL, gpiofind_sysfs_register);
 
-	return status;
+	return 0;
 }
 postcore_initcall(gpiolib_sysfs_init);