Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 6046 insertions, 0 deletions

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
new file mode 100644
index 000000000..51c4f604d
--- /dev/null
+++ b/drivers/regulator/core.c
@@ -0,0 +1,6046 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+//
+// core.c  --  Voltage/Current Regulator framework.
+//
+// Copyright 2007, 2008 Wolfson Microelectronics PLC.
+// Copyright 2008 SlimLogic Ltd.
+//
+// Author: Liam Girdwood <lrg@slimlogic.co.uk>
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/debugfs.h>
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/async.h>
+#include <linux/err.h>
+#include <linux/mutex.h>
+#include <linux/suspend.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/of.h>
+#include <linux/regmap.h>
+#include <linux/regulator/of_regulator.h>
+#include <linux/regulator/consumer.h>
+#include <linux/regulator/coupler.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+#include <linux/module.h>
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/regulator.h>
+
+#include "dummy.h"
+#include "internal.h"
+
+#define rdev_crit(rdev, fmt, ...)					\
+	pr_crit("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
+#define rdev_err(rdev, fmt, ...)					\
+	pr_err("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
+#define rdev_warn(rdev, fmt, ...)					\
+	pr_warn("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
+#define rdev_info(rdev, fmt, ...)					\
+	pr_info("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
+#define rdev_dbg(rdev, fmt, ...)					\
+	pr_debug("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
+
+static DEFINE_WW_CLASS(regulator_ww_class);
+static DEFINE_MUTEX(regulator_nesting_mutex);
+static DEFINE_MUTEX(regulator_list_mutex);
+static LIST_HEAD(regulator_map_list);
+static LIST_HEAD(regulator_ena_gpio_list);
+static LIST_HEAD(regulator_supply_alias_list);
+static LIST_HEAD(regulator_coupler_list);
+static bool has_full_constraints;
+
+static struct dentry *debugfs_root;
+
+/*
+ * struct regulator_map
+ *
+ * Used to provide symbolic supply names to devices.
+ */
+struct regulator_map {
+	struct list_head list;
+	const char *dev_name;   /* The dev_name() for the consumer */
+	const char *supply;
+	struct regulator_dev *regulator;
+};
+
+/*
+ * struct regulator_enable_gpio
+ *
+ * Management for shared enable GPIO pin
+ */
+struct regulator_enable_gpio {
+	struct list_head list;
+	struct gpio_desc *gpiod;
+	u32 enable_count;	/* a number of enabled shared GPIO */
+	u32 request_count;	/* a number of requested shared GPIO */
+};
+
+/*
+ * struct regulator_supply_alias
+ *
+ * Used to map lookups for a supply onto an alternative device.
+ */
+struct regulator_supply_alias {
+	struct list_head list;
+	struct device *src_dev;
+	const char *src_supply;
+	struct device *alias_dev;
+	const char *alias_supply;
+};
+
+static int _regulator_is_enabled(struct regulator_dev *rdev);
+static int _regulator_disable(struct regulator *regulator);
+static int _regulator_get_current_limit(struct regulator_dev *rdev);
+static unsigned int _regulator_get_mode(struct regulator_dev *rdev);
+static int _notifier_call_chain(struct regulator_dev *rdev,
+				  unsigned long event, void *data);
+static int _regulator_do_set_voltage(struct regulator_dev *rdev,
+				     int min_uV, int max_uV);
+static int regulator_balance_voltage(struct regulator_dev *rdev,
+				     suspend_state_t state);
+static struct regulator *create_regulator(struct regulator_dev *rdev,
+					  struct device *dev,
+					  const char *supply_name);
+static void destroy_regulator(struct regulator *regulator);
+static void _regulator_put(struct regulator *regulator);
+
+const char *rdev_get_name(struct regulator_dev *rdev)
+{
+	if (rdev->constraints && rdev->constraints->name)
+		return rdev->constraints->name;
+	else if (rdev->desc->name)
+		return rdev->desc->name;
+	else
+		return "";
+}
+
+static bool have_full_constraints(void)
+{
+	return has_full_constraints || of_have_populated_dt();
+}
+
+static bool regulator_ops_is_valid(struct regulator_dev *rdev, int ops)
+{
+	if (!rdev->constraints) {
+		rdev_err(rdev, "no constraints\n");
+		return false;
+	}
+
+	if (rdev->constraints->valid_ops_mask & ops)
+		return true;
+
+	return false;
+}
+
+/**
+ * regulator_lock_nested - lock a single regulator
+ * @rdev:		regulator source
+ * @ww_ctx:		w/w mutex acquire context
+ *
+ * This function can be called many times by one task on
+ * a single regulator and its mutex will be locked only
+ * once. If a task, which is calling this function is other
+ * than the one, which initially locked the mutex, it will
+ * wait on mutex.
+ */
+static inline int regulator_lock_nested(struct regulator_dev *rdev,
+					struct ww_acquire_ctx *ww_ctx)
+{
+	bool lock = false;
+	int ret = 0;
+
+	mutex_lock(&regulator_nesting_mutex);
+
+	if (ww_ctx || !ww_mutex_trylock(&rdev->mutex)) {
+		if (rdev->mutex_owner == current)
+			rdev->ref_cnt++;
+		else
+			lock = true;
+
+		if (lock) {
+			mutex_unlock(&regulator_nesting_mutex);
+			ret = ww_mutex_lock(&rdev->mutex, ww_ctx);
+			mutex_lock(&regulator_nesting_mutex);
+		}
+	} else {
+		lock = true;
+	}
+
+	if (lock && ret != -EDEADLK) {
+		rdev->ref_cnt++;
+		rdev->mutex_owner = current;
+	}
+
+	mutex_unlock(&regulator_nesting_mutex);
+
+	return ret;
+}
+
+/**
+ * regulator_lock - lock a single regulator
+ * @rdev:		regulator source
+ *
+ * This function can be called many times by one task on
+ * a single regulator and its mutex will be locked only
+ * once. If a task, which is calling this function is other
+ * than the one, which initially locked the mutex, it will
+ * wait on mutex.
+ */
+static void regulator_lock(struct regulator_dev *rdev)
+{
+	regulator_lock_nested(rdev, NULL);
+}
+
+/**
+ * regulator_unlock - unlock a single regulator
+ * @rdev:		regulator_source
+ *
+ * This function unlocks the mutex when the
+ * reference counter reaches 0.
+ */
+static void regulator_unlock(struct regulator_dev *rdev)
+{
+	mutex_lock(&regulator_nesting_mutex);
+
+	if (--rdev->ref_cnt == 0) {
+		rdev->mutex_owner = NULL;
+		ww_mutex_unlock(&rdev->mutex);
+	}
+
+	WARN_ON_ONCE(rdev->ref_cnt < 0);
+
+	mutex_unlock(&regulator_nesting_mutex);
+}
+
+/**
+ * regulator_lock_two - lock two regulators
+ * @rdev1:		first regulator
+ * @rdev2:		second regulator
+ * @ww_ctx:		w/w mutex acquire context
+ *
+ * Locks both rdevs using the regulator_ww_class.
+ */
+static void regulator_lock_two(struct regulator_dev *rdev1,
+			       struct regulator_dev *rdev2,
+			       struct ww_acquire_ctx *ww_ctx)
+{
+	struct regulator_dev *tmp;
+	int ret;
+
+	ww_acquire_init(ww_ctx, &regulator_ww_class);
+
+	/* Try to just grab both of them */
+	ret = regulator_lock_nested(rdev1, ww_ctx);
+	WARN_ON(ret);
+	ret = regulator_lock_nested(rdev2, ww_ctx);
+	if (ret != -EDEADLOCK) {
+		WARN_ON(ret);
+		goto exit;
+	}
+
+	while (true) {
+		/*
+		 * Start of loop: rdev1 was locked and rdev2 was contended.
+		 * Need to unlock rdev1, slowly lock rdev2, then try rdev1
+		 * again.
+		 */
+		regulator_unlock(rdev1);
+
+		ww_mutex_lock_slow(&rdev2->mutex, ww_ctx);
+		rdev2->ref_cnt++;
+		rdev2->mutex_owner = current;
+		ret = regulator_lock_nested(rdev1, ww_ctx);
+
+		if (ret == -EDEADLOCK) {
+			/* More contention; swap which needs to be slow */
+			tmp = rdev1;
+			rdev1 = rdev2;
+			rdev2 = tmp;
+		} else {
+			WARN_ON(ret);
+			break;
+		}
+	}
+
+exit:
+	ww_acquire_done(ww_ctx);
+}
+
+/**
+ * regulator_unlock_two - unlock two regulators
+ * @rdev1:		first regulator
+ * @rdev2:		second regulator
+ * @ww_ctx:		w/w mutex acquire context
+ *
+ * The inverse of regulator_lock_two().
+ */
+
+static void regulator_unlock_two(struct regulator_dev *rdev1,
+				 struct regulator_dev *rdev2,
+				 struct ww_acquire_ctx *ww_ctx)
+{
+	regulator_unlock(rdev2);
+	regulator_unlock(rdev1);
+	ww_acquire_fini(ww_ctx);
+}
+
+static bool regulator_supply_is_couple(struct regulator_dev *rdev)
+{
+	struct regulator_dev *c_rdev;
+	int i;
+
+	for (i = 1; i < rdev->coupling_desc.n_coupled; i++) {
+		c_rdev = rdev->coupling_desc.coupled_rdevs[i];
+
+		if (rdev->supply->rdev == c_rdev)
+			return true;
+	}
+
+	return false;
+}
+
+static void regulator_unlock_recursive(struct regulator_dev *rdev,
+				       unsigned int n_coupled)
+{
+	struct regulator_dev *c_rdev, *supply_rdev;
+	int i, supply_n_coupled;
+
+	for (i = n_coupled; i > 0; i--) {
+		c_rdev = rdev->coupling_desc.coupled_rdevs[i - 1];
+
+		if (!c_rdev)
+			continue;
+
+		if (c_rdev->supply && !regulator_supply_is_couple(c_rdev)) {
+			supply_rdev = c_rdev->supply->rdev;
+			supply_n_coupled = supply_rdev->coupling_desc.n_coupled;
+
+			regulator_unlock_recursive(supply_rdev,
+						   supply_n_coupled);
+		}
+
+		regulator_unlock(c_rdev);
+	}
+}
+
+static int regulator_lock_recursive(struct regulator_dev *rdev,
+				    struct regulator_dev **new_contended_rdev,
+				    struct regulator_dev **old_contended_rdev,
+				    struct ww_acquire_ctx *ww_ctx)
+{
+	struct regulator_dev *c_rdev;
+	int i, err;
+
+	for (i = 0; i < rdev->coupling_desc.n_coupled; i++) {
+		c_rdev = rdev->coupling_desc.coupled_rdevs[i];
+
+		if (!c_rdev)
+			continue;
+
+		if (c_rdev != *old_contended_rdev) {
+			err = regulator_lock_nested(c_rdev, ww_ctx);
+			if (err) {
+				if (err == -EDEADLK) {
+					*new_contended_rdev = c_rdev;
+					goto err_unlock;
+				}
+
+				/* shouldn't happen */
+				WARN_ON_ONCE(err != -EALREADY);
+			}
+		} else {
+			*old_contended_rdev = NULL;
+		}
+
+		if (c_rdev->supply && !regulator_supply_is_couple(c_rdev)) {
+			err = regulator_lock_recursive(c_rdev->supply->rdev,
+						       new_contended_rdev,
+						       old_contended_rdev,
+						       ww_ctx);
+			if (err) {
+				regulator_unlock(c_rdev);
+				goto err_unlock;
+			}
+		}
+	}
+
+	return 0;
+
+err_unlock:
+	regulator_unlock_recursive(rdev, i);
+
+	return err;
+}
+
+/**
+ * regulator_unlock_dependent - unlock regulator's suppliers and coupled
+ *				regulators
+ * @rdev:			regulator source
+ * @ww_ctx:			w/w mutex acquire context
+ *
+ * Unlock all regulators related with rdev by coupling or supplying.
+ */
+static void regulator_unlock_dependent(struct regulator_dev *rdev,
+				       struct ww_acquire_ctx *ww_ctx)
+{
+	regulator_unlock_recursive(rdev, rdev->coupling_desc.n_coupled);
+	ww_acquire_fini(ww_ctx);
+}
+
+/**
+ * regulator_lock_dependent - lock regulator's suppliers and coupled regulators
+ * @rdev:			regulator source
+ * @ww_ctx:			w/w mutex acquire context
+ *
+ * This function as a wrapper on regulator_lock_recursive(), which locks
+ * all regulators related with rdev by coupling or supplying.
+ */
+static void regulator_lock_dependent(struct regulator_dev *rdev,
+				     struct ww_acquire_ctx *ww_ctx)
+{
+	struct regulator_dev *new_contended_rdev = NULL;
+	struct regulator_dev *old_contended_rdev = NULL;
+	int err;
+
+	mutex_lock(&regulator_list_mutex);
+
+	ww_acquire_init(ww_ctx, &regulator_ww_class);
+
+	do {
+		if (new_contended_rdev) {
+			ww_mutex_lock_slow(&new_contended_rdev->mutex, ww_ctx);
+			old_contended_rdev = new_contended_rdev;
+			old_contended_rdev->ref_cnt++;
+			old_contended_rdev->mutex_owner = current;
+		}
+
+		err = regulator_lock_recursive(rdev,
+					       &new_contended_rdev,
+					       &old_contended_rdev,
+					       ww_ctx);
+
+		if (old_contended_rdev)
+			regulator_unlock(old_contended_rdev);
+
+	} while (err == -EDEADLK);
+
+	ww_acquire_done(ww_ctx);
+
+	mutex_unlock(&regulator_list_mutex);
+}
+
+/**
+ * of_get_child_regulator - get a child regulator device node
+ * based on supply name
+ * @parent: Parent device node
+ * @prop_name: Combination regulator supply name and "-supply"
+ *
+ * Traverse all child nodes.
+ * Extract the child regulator device node corresponding to the supply name.
+ * returns the device node corresponding to the regulator if found, else
+ * returns NULL.
+ */
+static struct device_node *of_get_child_regulator(struct device_node *parent,
+						  const char *prop_name)
+{
+	struct device_node *regnode = NULL;
+	struct device_node *child = NULL;
+
+	for_each_child_of_node(parent, child) {
+		regnode = of_parse_phandle(child, prop_name, 0);
+
+		if (!regnode) {
+			regnode = of_get_child_regulator(child, prop_name);
+			if (regnode)
+				goto err_node_put;
+		} else {
+			goto err_node_put;
+		}
+	}
+	return NULL;
+
+err_node_put:
+	of_node_put(child);
+	return regnode;
+}
+
+/**
+ * of_get_regulator - get a regulator device node based on supply name
+ * @dev: Device pointer for the consumer (of regulator) device
+ * @supply: regulator supply name
+ *
+ * Extract the regulator device node corresponding to the supply name.
+ * returns the device node corresponding to the regulator if found, else
+ * returns NULL.
+ */
+static struct device_node *of_get_regulator(struct device *dev, const char *supply)
+{
+	struct device_node *regnode = NULL;
+	char prop_name[64]; /* 64 is max size of property name */
+
+	dev_dbg(dev, "Looking up %s-supply from device tree\n", supply);
+
+	snprintf(prop_name, 64, "%s-supply", supply);
+	regnode = of_parse_phandle(dev->of_node, prop_name, 0);
+
+	if (!regnode) {
+		regnode = of_get_child_regulator(dev->of_node, prop_name);
+		if (regnode)
+			return regnode;
+
+		dev_dbg(dev, "Looking up %s property in node %pOF failed\n",
+				prop_name, dev->of_node);
+		return NULL;
+	}
+	return regnode;
+}
+
+/* Platform voltage constraint check */
+int regulator_check_voltage(struct regulator_dev *rdev,
+			    int *min_uV, int *max_uV)
+{
+	BUG_ON(*min_uV > *max_uV);
+
+	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE)) {
+		rdev_err(rdev, "voltage operation not allowed\n");
+		return -EPERM;
+	}
+
+	if (*max_uV > rdev->constraints->max_uV)
+		*max_uV = rdev->constraints->max_uV;
+	if (*min_uV < rdev->constraints->min_uV)
+		*min_uV = rdev->constraints->min_uV;
+
+	if (*min_uV > *max_uV) {
+		rdev_err(rdev, "unsupportable voltage range: %d-%duV\n",
+			 *min_uV, *max_uV);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/* return 0 if the state is valid */
+static int regulator_check_states(suspend_state_t state)
+{
+	return (state > PM_SUSPEND_MAX || state == PM_SUSPEND_TO_IDLE);
+}
+
+/* Make sure we select a voltage that suits the needs of all
+ * regulator consumers
+ */
+int regulator_check_consumers(struct regulator_dev *rdev,
+			      int *min_uV, int *max_uV,
+			      suspend_state_t state)
+{
+	struct regulator *regulator;
+	struct regulator_voltage *voltage;
+
+	list_for_each_entry(regulator, &rdev->consumer_list, list) {
+		voltage = &regulator->voltage[state];
+		/*
+		 * Assume consumers that didn't say anything are OK
+		 * with anything in the constraint range.
+		 */
+		if (!voltage->min_uV && !voltage->max_uV)
+			continue;
+
+		if (*max_uV > voltage->max_uV)
+			*max_uV = voltage->max_uV;
+		if (*min_uV < voltage->min_uV)
+			*min_uV = voltage->min_uV;
+	}
+
+	if (*min_uV > *max_uV) {
+		rdev_err(rdev, "Restricting voltage, %u-%uuV\n",
+			*min_uV, *max_uV);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/* current constraint check */
+static int regulator_check_current_limit(struct regulator_dev *rdev,
+					int *min_uA, int *max_uA)
+{
+	BUG_ON(*min_uA > *max_uA);
+
+	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_CURRENT)) {
+		rdev_err(rdev, "current operation not allowed\n");
+		return -EPERM;
+	}
+
+	if (*max_uA > rdev->constraints->max_uA)
+		*max_uA = rdev->constraints->max_uA;
+	if (*min_uA < rdev->constraints->min_uA)
+		*min_uA = rdev->constraints->min_uA;
+
+	if (*min_uA > *max_uA) {
+		rdev_err(rdev, "unsupportable current range: %d-%duA\n",
+			 *min_uA, *max_uA);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/* operating mode constraint check */
+static int regulator_mode_constrain(struct regulator_dev *rdev,
+				    unsigned int *mode)
+{
+	switch (*mode) {
+	case REGULATOR_MODE_FAST:
+	case REGULATOR_MODE_NORMAL:
+	case REGULATOR_MODE_IDLE:
+	case REGULATOR_MODE_STANDBY:
+		break;
+	default:
+		rdev_err(rdev, "invalid mode %x specified\n", *mode);
+		return -EINVAL;
+	}
+
+	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_MODE)) {
+		rdev_err(rdev, "mode operation not allowed\n");
+		return -EPERM;
+	}
+
+	/* The modes are bitmasks, the most power hungry modes having
+	 * the lowest values. If the requested mode isn't supported
+	 * try higher modes. */
+	while (*mode) {
+		if (rdev->constraints->valid_modes_mask & *mode)
+			return 0;
+		*mode /= 2;
+	}
+
+	return -EINVAL;
+}
+
+static inline struct regulator_state *
+regulator_get_suspend_state(struct regulator_dev *rdev, suspend_state_t state)
+{
+	if (rdev->constraints == NULL)
+		return NULL;
+
+	switch (state) {
+	case PM_SUSPEND_STANDBY:
+		return &rdev->constraints->state_standby;
+	case PM_SUSPEND_MEM:
+		return &rdev->constraints->state_mem;
+	case PM_SUSPEND_MAX:
+		return &rdev->constraints->state_disk;
+	default:
+		return NULL;
+	}
+}
+
+static const struct regulator_state *
+regulator_get_suspend_state_check(struct regulator_dev *rdev, suspend_state_t state)
+{
+	const struct regulator_state *rstate;
+
+	rstate = regulator_get_suspend_state(rdev, state);
+	if (rstate == NULL)
+		return NULL;
+
+	/* If we have no suspend mode configuration don't set anything;
+	 * only warn if the driver implements set_suspend_voltage or
+	 * set_suspend_mode callback.
+	 */
+	if (rstate->enabled != ENABLE_IN_SUSPEND &&
+	    rstate->enabled != DISABLE_IN_SUSPEND) {
+		if (rdev->desc->ops->set_suspend_voltage ||
+		    rdev->desc->ops->set_suspend_mode)
+			rdev_warn(rdev, "No configuration\n");
+		return NULL;
+	}
+
+	return rstate;
+}
+
+static ssize_t regulator_uV_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct regulator_dev *rdev = dev_get_drvdata(dev);
+	int uV;
+
+	regulator_lock(rdev);
+	uV = regulator_get_voltage_rdev(rdev);
+	regulator_unlock(rdev);
+
+	if (uV < 0)
+		return uV;
+	return sprintf(buf, "%d\n", uV);
+}
+static DEVICE_ATTR(microvolts, 0444, regulator_uV_show, NULL);
+
+static ssize_t regulator_uA_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct regulator_dev *rdev = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%d\n", _regulator_get_current_limit(rdev));
+}
+static DEVICE_ATTR(microamps, 0444, regulator_uA_show, NULL);
+
+static ssize_t name_show(struct device *dev, struct device_attribute *attr,
+			 char *buf)
+{
+	struct regulator_dev *rdev = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%s\n", rdev_get_name(rdev));
+}
+static DEVICE_ATTR_RO(name);
+
+static const char *regulator_opmode_to_str(int mode)
+{
+	switch (mode) {
+	case REGULATOR_MODE_FAST:
+		return "fast";
+	case REGULATOR_MODE_NORMAL:
+		return "normal";
+	case REGULATOR_MODE_IDLE:
+		return "idle";
+	case REGULATOR_MODE_STANDBY:
+		return "standby";
+	}
+	return "unknown";
+}
+
+static ssize_t regulator_print_opmode(char *buf, int mode)
+{
+	return sprintf(buf, "%s\n", regulator_opmode_to_str(mode));
+}
+
+static ssize_t regulator_opmode_show(struct device *dev,
+				    struct device_attribute *attr, char *buf)
+{
+	struct regulator_dev *rdev = dev_get_drvdata(dev);
+
+	return regulator_print_opmode(buf, _regulator_get_mode(rdev));
+}
+static DEVICE_ATTR(opmode, 0444, regulator_opmode_show, NULL);
+
+static ssize_t regulator_print_state(char *buf, int state)
+{
+	if (state > 0)
+		return sprintf(buf, "enabled\n");
+	else if (state == 0)
+		return sprintf(buf, "disabled\n");
+	else
+		return sprintf(buf, "unknown\n");
+}
+
+static ssize_t regulator_state_show(struct device *dev,
+				   struct device_attribute *attr, char *buf)
+{
+	struct regulator_dev *rdev = dev_get_drvdata(dev);
+	ssize_t ret;
+
+	regulator_lock(rdev);
+	ret = regulator_print_state(buf, _regulator_is_enabled(rdev));
+	regulator_unlock(rdev);
+
+	return ret;
+}
+static DEVICE_ATTR(state, 0444, regulator_state_show, NULL);
+
+static ssize_t regulator_status_show(struct device *dev,
+				   struct device_attribute *attr, char *buf)
+{
+	struct regulator_dev *rdev = dev_get_drvdata(dev);
+	int status;
+	char *label;
+
+	status = rdev->desc->ops->get_status(rdev);
+	if (status < 0)
+		return status;
+
+	switch (status) {
+	case REGULATOR_STATUS_OFF:
+		label = "off";
+		break;
+	case REGULATOR_STATUS_ON:
+		label = "on";
+		break;
+	case REGULATOR_STATUS_ERROR:
+		label = "error";
+		break;
+	case REGULATOR_STATUS_FAST:
+		label = "fast";
+		break;
+	case REGULATOR_STATUS_NORMAL:
+		label = "normal";
+		break;
+	case REGULATOR_STATUS_IDLE:
+		label = "idle";
+		break;
+	case REGULATOR_STATUS_STANDBY:
+		label = "standby";
+		break;
+	case REGULATOR_STATUS_BYPASS:
+		label = "bypass";
+		break;
+	case REGULATOR_STATUS_UNDEFINED:
+		label = "undefined";
+		break;
+	default:
+		return -ERANGE;
+	}
+
+	return sprintf(buf, "%s\n", label);
+}
+static DEVICE_ATTR(status, 0444, regulator_status_show, NULL);
+
+static ssize_t regulator_min_uA_show(struct device *dev,
+				    struct device_attribute *attr, char *buf)
+{
+	struct regulator_dev *rdev = dev_get_drvdata(dev);
+
+	if (!rdev->constraints)
+		return sprintf(buf, "constraint not defined\n");
+
+	return sprintf(buf, "%d\n", rdev->constraints->min_uA);
+}
+static DEVICE_ATTR(min_microamps, 0444, regulator_min_uA_show, NULL);
+
+static ssize_t regulator_max_uA_show(struct device *dev,
+				    struct device_attribute *attr, char *buf)
+{
+	struct regulator_dev *rdev = dev_get_drvdata(dev);
+
+	if (!rdev->constraints)
+		return sprintf(buf, "constraint not defined\n");
+
+	return sprintf(buf, "%d\n", rdev->constraints->max_uA);
+}
+static DEVICE_ATTR(max_microamps, 0444, regulator_max_uA_show, NULL);
+
+static ssize_t regulator_min_uV_show(struct device *dev,
+				    struct device_attribute *attr, char *buf)
+{
+	struct regulator_dev *rdev = dev_get_drvdata(dev);
+
+	if (!rdev->constraints)
+		return sprintf(buf, "constraint not defined\n");
+
+	return sprintf(buf, "%d\n", rdev->constraints->min_uV);
+}
+static DEVICE_ATTR(min_microvolts, 0444, regulator_min_uV_show, NULL);
+
+static ssize_t regulator_max_uV_show(struct device *dev,
+				    struct device_attribute *attr, char *buf)
+{
+	struct regulator_dev *rdev = dev_get_drvdata(dev);
+
+	if (!rdev->constraints)
+		return sprintf(buf, "constraint not defined\n");
+
+	return sprintf(buf, "%d\n", rdev->constraints->max_uV);
+}
+static DEVICE_ATTR(max_microvolts, 0444, regulator_max_uV_show, NULL);
+
+static ssize_t regulator_total_uA_show(struct device *dev,
+				      struct device_attribute *attr, char *buf)
+{
+	struct regulator_dev *rdev = dev_get_drvdata(dev);
+	struct regulator *regulator;
+	int uA = 0;
+
+	regulator_lock(rdev);
+	list_for_each_entry(regulator, &rdev->consumer_list, list) {
+		if (regulator->enable_count)
+			uA += regulator->uA_load;
+	}
+	regulator_unlock(rdev);
+	return sprintf(buf, "%d\n", uA);
+}
+static DEVICE_ATTR(requested_microamps, 0444, regulator_total_uA_show, NULL);
+
+static ssize_t num_users_show(struct device *dev, struct device_attribute *attr,
+			      char *buf)
+{
+	struct regulator_dev *rdev = dev_get_drvdata(dev);
+	return sprintf(buf, "%d\n", rdev->use_count);
+}
+static DEVICE_ATTR_RO(num_users);
+
+static ssize_t type_show(struct device *dev, struct device_attribute *attr,
+			 char *buf)
+{
+	struct regulator_dev *rdev = dev_get_drvdata(dev);
+
+	switch (rdev->desc->type) {
+	case REGULATOR_VOLTAGE:
+		return sprintf(buf, "voltage\n");
+	case REGULATOR_CURRENT:
+		return sprintf(buf, "current\n");
+	}
+	return sprintf(buf, "unknown\n");
+}
+static DEVICE_ATTR_RO(type);
+
+static ssize_t regulator_suspend_mem_uV_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct regulator_dev *rdev = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
+}
+static DEVICE_ATTR(suspend_mem_microvolts, 0444,
+		regulator_suspend_mem_uV_show, NULL);
+
+static ssize_t regulator_suspend_disk_uV_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct regulator_dev *rdev = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
+}
+static DEVICE_ATTR(suspend_disk_microvolts, 0444,
+		regulator_suspend_disk_uV_show, NULL);
+
+static ssize_t regulator_suspend_standby_uV_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct regulator_dev *rdev = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
+}
+static DEVICE_ATTR(suspend_standby_microvolts, 0444,
+		regulator_suspend_standby_uV_show, NULL);
+
+static ssize_t regulator_suspend_mem_mode_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct regulator_dev *rdev = dev_get_drvdata(dev);
+
+	return regulator_print_opmode(buf,
+		rdev->constraints->state_mem.mode);
+}
+static DEVICE_ATTR(suspend_mem_mode, 0444,
+		regulator_suspend_mem_mode_show, NULL);
+
+static ssize_t regulator_suspend_disk_mode_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct regulator_dev *rdev = dev_get_drvdata(dev);
+
+	return regulator_print_opmode(buf,
+		rdev->constraints->state_disk.mode);
+}
+static DEVICE_ATTR(suspend_disk_mode, 0444,
+		regulator_suspend_disk_mode_show, NULL);
+
+static ssize_t regulator_suspend_standby_mode_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct regulator_dev *rdev = dev_get_drvdata(dev);
+
+	return regulator_print_opmode(buf,
+		rdev->constraints->state_standby.mode);
+}
+static DEVICE_ATTR(suspend_standby_mode, 0444,
+		regulator_suspend_standby_mode_show, NULL);
+
+static ssize_t regulator_suspend_mem_state_show(struct device *dev,
+				   struct device_attribute *attr, char *buf)
+{
+	struct regulator_dev *rdev = dev_get_drvdata(dev);
+
+	return regulator_print_state(buf,
+			rdev->constraints->state_mem.enabled);
+}
+static DEVICE_ATTR(suspend_mem_state, 0444,
+		regulator_suspend_mem_state_show, NULL);
+
+static ssize_t regulator_suspend_disk_state_show(struct device *dev,
+				   struct device_attribute *attr, char *buf)
+{
+	struct regulator_dev *rdev = dev_get_drvdata(dev);
+
+	return regulator_print_state(buf,
+			rdev->constraints->state_disk.enabled);
+}
+static DEVICE_ATTR(suspend_disk_state, 0444,
+		regulator_suspend_disk_state_show, NULL);
+
+static ssize_t regulator_suspend_standby_state_show(struct device *dev,
+				   struct device_attribute *attr, char *buf)
+{
+	struct regulator_dev *rdev = dev_get_drvdata(dev);
+
+	return regulator_print_state(buf,
+			rdev->constraints->state_standby.enabled);
+}
+static DEVICE_ATTR(suspend_standby_state, 0444,
+		regulator_suspend_standby_state_show, NULL);
+
+static ssize_t regulator_bypass_show(struct device *dev,
+				     struct device_attribute *attr, char *buf)
+{
+	struct regulator_dev *rdev = dev_get_drvdata(dev);
+	const char *report;
+	bool bypass;
+	int ret;
+
+	ret = rdev->desc->ops->get_bypass(rdev, &bypass);
+
+	if (ret != 0)
+		report = "unknown";
+	else if (bypass)
+		report = "enabled";
+	else
+		report = "disabled";
+
+	return sprintf(buf, "%s\n", report);
+}
+static DEVICE_ATTR(bypass, 0444,
+		   regulator_bypass_show, NULL);
+
+/* Calculate the new optimum regulator operating mode based on the new total
+ * consumer load. All locks held by caller */
+static int drms_uA_update(struct regulator_dev *rdev)
+{
+	struct regulator *sibling;
+	int current_uA = 0, output_uV, input_uV, err;
+	unsigned int mode;
+
+	/*
+	 * first check to see if we can set modes at all, otherwise just
+	 * tell the consumer everything is OK.
+	 */
+	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_DRMS)) {
+		rdev_dbg(rdev, "DRMS operation not allowed\n");
+		return 0;
+	}
+
+	if (!rdev->desc->ops->get_optimum_mode &&
+	    !rdev->desc->ops->set_load)
+		return 0;
+
+	if (!rdev->desc->ops->set_mode &&
+	    !rdev->desc->ops->set_load)
+		return -EINVAL;
+
+	/* calc total requested load */
+	list_for_each_entry(sibling, &rdev->consumer_list, list) {
+		if (sibling->enable_count)
+			current_uA += sibling->uA_load;
+	}
+
+	current_uA += rdev->constraints->system_load;
+
+	if (rdev->desc->ops->set_load) {
+		/* set the optimum mode for our new total regulator load */
+		err = rdev->desc->ops->set_load(rdev, current_uA);
+		if (err < 0)
+			rdev_err(rdev, "failed to set load %d: %pe\n",
+				 current_uA, ERR_PTR(err));
+	} else {
+		/* get output voltage */
+		output_uV = regulator_get_voltage_rdev(rdev);
+		if (output_uV <= 0) {
+			rdev_err(rdev, "invalid output voltage found\n");
+			return -EINVAL;
+		}
+
+		/* get input voltage */
+		input_uV = 0;
+		if (rdev->supply)
+			input_uV = regulator_get_voltage_rdev(rdev->supply->rdev);
+		if (input_uV <= 0)
+			input_uV = rdev->constraints->input_uV;
+		if (input_uV <= 0) {
+			rdev_err(rdev, "invalid input voltage found\n");
+			return -EINVAL;
+		}
+
+		/* now get the optimum mode for our new total regulator load */
+		mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
+							 output_uV, current_uA);
+
+		/* check the new mode is allowed */
+		err = regulator_mode_constrain(rdev, &mode);
+		if (err < 0) {
+			rdev_err(rdev, "failed to get optimum mode @ %d uA %d -> %d uV: %pe\n",
+				 current_uA, input_uV, output_uV, ERR_PTR(err));
+			return err;
+		}
+
+		err = rdev->desc->ops->set_mode(rdev, mode);
+		if (err < 0)
+			rdev_err(rdev, "failed to set optimum mode %x: %pe\n",
+				 mode, ERR_PTR(err));
+	}
+
+	return err;
+}
+
+static int __suspend_set_state(struct regulator_dev *rdev,
+			       const struct regulator_state *rstate)
+{
+	int ret = 0;
+
+	if (rstate->enabled == ENABLE_IN_SUSPEND &&
+		rdev->desc->ops->set_suspend_enable)
+		ret = rdev->desc->ops->set_suspend_enable(rdev);
+	else if (rstate->enabled == DISABLE_IN_SUSPEND &&
+		rdev->desc->ops->set_suspend_disable)
+		ret = rdev->desc->ops->set_suspend_disable(rdev);
+	else /* OK if set_suspend_enable or set_suspend_disable is NULL */
+		ret = 0;
+
+	if (ret < 0) {
+		rdev_err(rdev, "failed to enabled/disable: %pe\n", ERR_PTR(ret));
+		return ret;
+	}
+
+	if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
+		ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
+		if (ret < 0) {
+			rdev_err(rdev, "failed to set voltage: %pe\n", ERR_PTR(ret));
+			return ret;
+		}
+	}
+
+	if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
+		ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
+		if (ret < 0) {
+			rdev_err(rdev, "failed to set mode: %pe\n", ERR_PTR(ret));
+			return ret;
+		}
+	}
+
+	return ret;
+}
+
+static int suspend_set_initial_state(struct regulator_dev *rdev)
+{
+	const struct regulator_state *rstate;
+
+	rstate = regulator_get_suspend_state_check(rdev,
+			rdev->constraints->initial_state);
+	if (!rstate)
+		return 0;
+
+	return __suspend_set_state(rdev, rstate);
+}
+
+#if defined(DEBUG) || defined(CONFIG_DYNAMIC_DEBUG)
+static void print_constraints_debug(struct regulator_dev *rdev)
+{
+	struct regulation_constraints *constraints = rdev->constraints;
+	char buf[160] = "";
+	size_t len = sizeof(buf) - 1;
+	int count = 0;
+	int ret;
+
+	if (constraints->min_uV && constraints->max_uV) {
+		if (constraints->min_uV == constraints->max_uV)
+			count += scnprintf(buf + count, len - count, "%d mV ",
+					   constraints->min_uV / 1000);
+		else
+			count += scnprintf(buf + count, len - count,
+					   "%d <--> %d mV ",
+					   constraints->min_uV / 1000,
+					   constraints->max_uV / 1000);
+	}
+
+	if (!constraints->min_uV ||
+	    constraints->min_uV != constraints->max_uV) {
+		ret = regulator_get_voltage_rdev(rdev);
+		if (ret > 0)
+			count += scnprintf(buf + count, len - count,
+					   "at %d mV ", ret / 1000);
+	}
+
+	if (constraints->uV_offset)
+		count += scnprintf(buf + count, len - count, "%dmV offset ",
+				   constraints->uV_offset / 1000);
+
+	if (constraints->min_uA && constraints->max_uA) {
+		if (constraints->min_uA == constraints->max_uA)
+			count += scnprintf(buf + count, len - count, "%d mA ",
+					   constraints->min_uA / 1000);
+		else
+			count += scnprintf(buf + count, len - count,
+					   "%d <--> %d mA ",
+					   constraints->min_uA / 1000,
+					   constraints->max_uA / 1000);
+	}
+
+	if (!constraints->min_uA ||
+	    constraints->min_uA != constraints->max_uA) {
+		ret = _regulator_get_current_limit(rdev);
+		if (ret > 0)
+			count += scnprintf(buf + count, len - count,
+					   "at %d mA ", ret / 1000);
+	}
+
+	if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
+		count += scnprintf(buf + count, len - count, "fast ");
+	if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
+		count += scnprintf(buf + count, len - count, "normal ");
+	if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
+		count += scnprintf(buf + count, len - count, "idle ");
+	if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
+		count += scnprintf(buf + count, len - count, "standby ");
+
+	if (!count)
+		count = scnprintf(buf, len, "no parameters");
+	else
+		--count;
+
+	count += scnprintf(buf + count, len - count, ", %s",
+		_regulator_is_enabled(rdev) ? "enabled" : "disabled");
+
+	rdev_dbg(rdev, "%s\n", buf);
+}
+#else /* !DEBUG && !CONFIG_DYNAMIC_DEBUG */
+static inline void print_constraints_debug(struct regulator_dev *rdev) {}
+#endif /* !DEBUG && !CONFIG_DYNAMIC_DEBUG */
+
+static void print_constraints(struct regulator_dev *rdev)
+{
+	struct regulation_constraints *constraints = rdev->constraints;
+
+	print_constraints_debug(rdev);
+
+	if ((constraints->min_uV != constraints->max_uV) &&
+	    !regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE))
+		rdev_warn(rdev,
+			  "Voltage range but no REGULATOR_CHANGE_VOLTAGE\n");
+}
+
+static int machine_constraints_voltage(struct regulator_dev *rdev,
+	struct regulation_constraints *constraints)
+{
+	const struct regulator_ops *ops = rdev->desc->ops;
+	int ret;
+
+	/* do we need to apply the constraint voltage */
+	if (rdev->constraints->apply_uV &&
+	    rdev->constraints->min_uV && rdev->constraints->max_uV) {
+		int target_min, target_max;
+		int current_uV = regulator_get_voltage_rdev(rdev);
+
+		if (current_uV == -ENOTRECOVERABLE) {
+			/* This regulator can't be read and must be initialized */
+			rdev_info(rdev, "Setting %d-%duV\n",
+				  rdev->constraints->min_uV,
+				  rdev->constraints->max_uV);
+			_regulator_do_set_voltage(rdev,
+						  rdev->constraints->min_uV,
+						  rdev->constraints->max_uV);
+			current_uV = regulator_get_voltage_rdev(rdev);
+		}
+
+		if (current_uV < 0) {
+			rdev_err(rdev,
+				 "failed to get the current voltage: %pe\n",
+				 ERR_PTR(current_uV));
+			return current_uV;
+		}
+
+		/*
+		 * If we're below the minimum voltage move up to the
+		 * minimum voltage, if we're above the maximum voltage
+		 * then move down to the maximum.
+		 */
+		target_min = current_uV;
+		target_max = current_uV;
+
+		if (current_uV < rdev->constraints->min_uV) {
+			target_min = rdev->constraints->min_uV;
+			target_max = rdev->constraints->min_uV;
+		}
+
+		if (current_uV > rdev->constraints->max_uV) {
+			target_min = rdev->constraints->max_uV;
+			target_max = rdev->constraints->max_uV;
+		}
+
+		if (target_min != current_uV || target_max != current_uV) {
+			rdev_info(rdev, "Bringing %duV into %d-%duV\n",
+				  current_uV, target_min, target_max);
+			ret = _regulator_do_set_voltage(
+				rdev, target_min, target_max);
+			if (ret < 0) {
+				rdev_err(rdev,
+					"failed to apply %d-%duV constraint: %pe\n",
+					target_min, target_max, ERR_PTR(ret));
+				return ret;
+			}
+		}
+	}
+
+	/* constrain machine-level voltage specs to fit
+	 * the actual range supported by this regulator.
+	 */
+	if (ops->list_voltage && rdev->desc->n_voltages) {
+		int	count = rdev->desc->n_voltages;
+		int	i;
+		int	min_uV = INT_MAX;
+		int	max_uV = INT_MIN;
+		int	cmin = constraints->min_uV;
+		int	cmax = constraints->max_uV;
+
+		/* it's safe to autoconfigure fixed-voltage supplies
+		   and the constraints are used by list_voltage. */
+		if (count == 1 && !cmin) {
+			cmin = 1;
+			cmax = INT_MAX;
+			constraints->min_uV = cmin;
+			constraints->max_uV = cmax;
+		}
+
+		/* voltage constraints are optional */
+		if ((cmin == 0) && (cmax == 0))
+			return 0;
+
+		/* else require explicit machine-level constraints */
+		if (cmin <= 0 || cmax <= 0 || cmax < cmin) {
+			rdev_err(rdev, "invalid voltage constraints\n");
+			return -EINVAL;
+		}
+
+		/* no need to loop voltages if range is continuous */
+		if (rdev->desc->continuous_voltage_range)
+			return 0;
+
+		/* initial: [cmin..cmax] valid, [min_uV..max_uV] not */
+		for (i = 0; i < count; i++) {
+			int	value;
+
+			value = ops->list_voltage(rdev, i);
+			if (value <= 0)
+				continue;
+
+			/* maybe adjust [min_uV..max_uV] */
+			if (value >= cmin && value < min_uV)
+				min_uV = value;
+			if (value <= cmax && value > max_uV)
+				max_uV = value;
+		}
+
+		/* final: [min_uV..max_uV] valid iff constraints valid */
+		if (max_uV < min_uV) {
+			rdev_err(rdev,
+				 "unsupportable voltage constraints %u-%uuV\n",
+				 min_uV, max_uV);
+			return -EINVAL;
+		}
+
+		/* use regulator's subset of machine constraints */
+		if (constraints->min_uV < min_uV) {
+			rdev_dbg(rdev, "override min_uV, %d -> %d\n",
+				 constraints->min_uV, min_uV);
+			constraints->min_uV = min_uV;
+		}
+		if (constraints->max_uV > max_uV) {
+			rdev_dbg(rdev, "override max_uV, %d -> %d\n",
+				 constraints->max_uV, max_uV);
+			constraints->max_uV = max_uV;
+		}
+	}
+
+	return 0;
+}
+
+static int machine_constraints_current(struct regulator_dev *rdev,
+	struct regulation_constraints *constraints)
+{
+	const struct regulator_ops *ops = rdev->desc->ops;
+	int ret;
+
+	if (!constraints->min_uA && !constraints->max_uA)
+		return 0;
+
+	if (constraints->min_uA > constraints->max_uA) {
+		rdev_err(rdev, "Invalid current constraints\n");
+		return -EINVAL;
+	}
+
+	if (!ops->set_current_limit || !ops->get_current_limit) {
+		rdev_warn(rdev, "Operation of current configuration missing\n");
+		return 0;
+	}
+
+	/* Set regulator current in constraints range */
+	ret = ops->set_current_limit(rdev, constraints->min_uA,
+			constraints->max_uA);
+	if (ret < 0) {
+		rdev_err(rdev, "Failed to set current constraint, %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int _regulator_do_enable(struct regulator_dev *rdev);
+
+/**
+ * set_machine_constraints - sets regulator constraints
+ * @rdev: regulator source
+ *
+ * Allows platform initialisation code to define and constrain
+ * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
+ * Constraints *must* be set by platform code in order for some
+ * regulator operations to proceed i.e. set_voltage, set_current_limit,
+ * set_mode.
+ */
+static int set_machine_constraints(struct regulator_dev *rdev)
+{
+	int ret = 0;
+	const struct regulator_ops *ops = rdev->desc->ops;
+
+	ret = machine_constraints_voltage(rdev, rdev->constraints);
+	if (ret != 0)
+		return ret;
+
+	ret = machine_constraints_current(rdev, rdev->constraints);
+	if (ret != 0)
+		return ret;
+
+	if (rdev->constraints->ilim_uA && ops->set_input_current_limit) {
+		ret = ops->set_input_current_limit(rdev,
+						   rdev->constraints->ilim_uA);
+		if (ret < 0) {
+			rdev_err(rdev, "failed to set input limit: %pe\n", ERR_PTR(ret));
+			return ret;
+		}
+	}
+
+	/* do we need to setup our suspend state */
+	if (rdev->constraints->initial_state) {
+		ret = suspend_set_initial_state(rdev);
+		if (ret < 0) {
+			rdev_err(rdev, "failed to set suspend state: %pe\n", ERR_PTR(ret));
+			return ret;
+		}
+	}
+
+	if (rdev->constraints->initial_mode) {
+		if (!ops->set_mode) {
+			rdev_err(rdev, "no set_mode operation\n");
+			return -EINVAL;
+		}
+
+		ret = ops->set_mode(rdev, rdev->constraints->initial_mode);
+		if (ret < 0) {
+			rdev_err(rdev, "failed to set initial mode: %pe\n", ERR_PTR(ret));
+			return ret;
+		}
+	} else if (rdev->constraints->system_load) {
+		/*
+		 * We'll only apply the initial system load if an
+		 * initial mode wasn't specified.
+		 */
+		drms_uA_update(rdev);
+	}
+
+	if ((rdev->constraints->ramp_delay || rdev->constraints->ramp_disable)
+		&& ops->set_ramp_delay) {
+		ret = ops->set_ramp_delay(rdev, rdev->constraints->ramp_delay);
+		if (ret < 0) {
+			rdev_err(rdev, "failed to set ramp_delay: %pe\n", ERR_PTR(ret));
+			return ret;
+		}
+	}
+
+	if (rdev->constraints->pull_down && ops->set_pull_down) {
+		ret = ops->set_pull_down(rdev);
+		if (ret < 0) {
+			rdev_err(rdev, "failed to set pull down: %pe\n", ERR_PTR(ret));
+			return ret;
+		}
+	}
+
+	if (rdev->constraints->soft_start && ops->set_soft_start) {
+		ret = ops->set_soft_start(rdev);
+		if (ret < 0) {
+			rdev_err(rdev, "failed to set soft start: %pe\n", ERR_PTR(ret));
+			return ret;
+		}
+	}
+
+	if (rdev->constraints->over_current_protection
+		&& ops->set_over_current_protection) {
+		ret = ops->set_over_current_protection(rdev);
+		if (ret < 0) {
+			rdev_err(rdev, "failed to set over current protection: %pe\n",
+				 ERR_PTR(ret));
+			return ret;
+		}
+	}
+
+	if (rdev->constraints->active_discharge && ops->set_active_discharge) {
+		bool ad_state = (rdev->constraints->active_discharge ==
+			      REGULATOR_ACTIVE_DISCHARGE_ENABLE) ? true : false;
+
+		ret = ops->set_active_discharge(rdev, ad_state);
+		if (ret < 0) {
+			rdev_err(rdev, "failed to set active discharge: %pe\n", ERR_PTR(ret));
+			return ret;
+		}
+	}
+
+	/* If the constraints say the regulator should be on at this point
+	 * and we have control then make sure it is enabled.
+	 */
+	if (rdev->constraints->always_on || rdev->constraints->boot_on) {
+		/* If we want to enable this regulator, make sure that we know
+		 * the supplying regulator.
+		 */
+		if (rdev->supply_name && !rdev->supply)
+			return -EPROBE_DEFER;
+
+		/* If supplying regulator has already been enabled,
+		 * it's not intended to have use_count increment
+		 * when rdev is only boot-on.
+		 */
+		if (rdev->supply &&
+		    (rdev->constraints->always_on ||
+		     !regulator_is_enabled(rdev->supply))) {
+			ret = regulator_enable(rdev->supply);
+			if (ret < 0) {
+				_regulator_put(rdev->supply);
+				rdev->supply = NULL;
+				return ret;
+			}
+		}
+
+		ret = _regulator_do_enable(rdev);
+		if (ret < 0 && ret != -EINVAL) {
+			rdev_err(rdev, "failed to enable: %pe\n", ERR_PTR(ret));
+			return ret;
+		}
+
+		if (rdev->constraints->always_on)
+			rdev->use_count++;
+	}
+
+	print_constraints(rdev);
+	return 0;
+}
+
+/**
+ * set_supply - set regulator supply regulator
+ * @rdev: regulator (locked)
+ * @supply_rdev: supply regulator (locked))
+ *
+ * Called by platform initialisation code to set the supply regulator for this
+ * regulator. This ensures that a regulators supply will also be enabled by the
+ * core if it's child is enabled.
+ */
+static int set_supply(struct regulator_dev *rdev,
+		      struct regulator_dev *supply_rdev)
+{
+	int err;
+
+	rdev_info(rdev, "supplied by %s\n", rdev_get_name(supply_rdev));
+
+	if (!try_module_get(supply_rdev->owner))
+		return -ENODEV;
+
+	rdev->supply = create_regulator(supply_rdev, &rdev->dev, "SUPPLY");
+	if (rdev->supply == NULL) {
+		module_put(supply_rdev->owner);
+		err = -ENOMEM;
+		return err;
+	}
+	supply_rdev->open_count++;
+
+	return 0;
+}
+
+/**
+ * set_consumer_device_supply - Bind a regulator to a symbolic supply
+ * @rdev:         regulator source
+ * @consumer_dev_name: dev_name() string for device supply applies to
+ * @supply:       symbolic name for supply
+ *
+ * Allows platform initialisation code to map physical regulator
+ * sources to symbolic names for supplies for use by devices.  Devices
+ * should use these symbolic names to request regulators, avoiding the
+ * need to provide board-specific regulator names as platform data.
+ */
+static int set_consumer_device_supply(struct regulator_dev *rdev,
+				      const char *consumer_dev_name,
+				      const char *supply)
+{
+	struct regulator_map *node, *new_node;
+	int has_dev;
+
+	if (supply == NULL)
+		return -EINVAL;
+
+	if (consumer_dev_name != NULL)
+		has_dev = 1;
+	else
+		has_dev = 0;
+
+	new_node = kzalloc(sizeof(struct regulator_map), GFP_KERNEL);
+	if (new_node == NULL)
+		return -ENOMEM;
+
+	new_node->regulator = rdev;
+	new_node->supply = supply;
+
+	if (has_dev) {
+		new_node->dev_name = kstrdup(consumer_dev_name, GFP_KERNEL);
+		if (new_node->dev_name == NULL) {
+			kfree(new_node);
+			return -ENOMEM;
+		}
+	}
+
+	mutex_lock(&regulator_list_mutex);
+	list_for_each_entry(node, &regulator_map_list, list) {
+		if (node->dev_name && consumer_dev_name) {
+			if (strcmp(node->dev_name, consumer_dev_name) != 0)
+				continue;
+		} else if (node->dev_name || consumer_dev_name) {
+			continue;
+		}
+
+		if (strcmp(node->supply, supply) != 0)
+			continue;
+
+		pr_debug("%s: %s/%s is '%s' supply; fail %s/%s\n",
+			 consumer_dev_name,
+			 dev_name(&node->regulator->dev),
+			 node->regulator->desc->name,
+			 supply,
+			 dev_name(&rdev->dev), rdev_get_name(rdev));
+		goto fail;
+	}
+
+	list_add(&new_node->list, &regulator_map_list);
+	mutex_unlock(&regulator_list_mutex);
+
+	return 0;
+
+fail:
+	mutex_unlock(&regulator_list_mutex);
+	kfree(new_node->dev_name);
+	kfree(new_node);
+	return -EBUSY;
+}
+
+static void unset_regulator_supplies(struct regulator_dev *rdev)
+{
+	struct regulator_map *node, *n;
+
+	list_for_each_entry_safe(node, n, &regulator_map_list, list) {
+		if (rdev == node->regulator) {
+			list_del(&node->list);
+			kfree(node->dev_name);
+			kfree(node);
+		}
+	}
+}
+
+#ifdef CONFIG_DEBUG_FS
+static ssize_t constraint_flags_read_file(struct file *file,
+					  char __user *user_buf,
+					  size_t count, loff_t *ppos)
+{
+	const struct regulator *regulator = file->private_data;
+	const struct regulation_constraints *c = regulator->rdev->constraints;
+	char *buf;
+	ssize_t ret;
+
+	if (!c)
+		return 0;
+
+	buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	ret = snprintf(buf, PAGE_SIZE,
+			"always_on: %u\n"
+			"boot_on: %u\n"
+			"apply_uV: %u\n"
+			"ramp_disable: %u\n"
+			"soft_start: %u\n"
+			"pull_down: %u\n"
+			"over_current_protection: %u\n",
+			c->always_on,
+			c->boot_on,
+			c->apply_uV,
+			c->ramp_disable,
+			c->soft_start,
+			c->pull_down,
+			c->over_current_protection);
+
+	ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
+	kfree(buf);
+
+	return ret;
+}
+
+#endif
+
+static const struct file_operations constraint_flags_fops = {
+#ifdef CONFIG_DEBUG_FS
+	.open = simple_open,
+	.read = constraint_flags_read_file,
+	.llseek = default_llseek,
+#endif
+};
+
+#define REG_STR_SIZE	64
+
+static struct regulator *create_regulator(struct regulator_dev *rdev,
+					  struct device *dev,
+					  const char *supply_name)
+{
+	struct regulator *regulator;
+	int err = 0;
+
+	lockdep_assert_held_once(&rdev->mutex.base);
+
+	if (dev) {
+		char buf[REG_STR_SIZE];
+		int size;
+
+		size = snprintf(buf, REG_STR_SIZE, "%s-%s",
+				dev->kobj.name, supply_name);
+		if (size >= REG_STR_SIZE)
+			return NULL;
+
+		supply_name = kstrdup(buf, GFP_KERNEL);
+		if (supply_name == NULL)
+			return NULL;
+	} else {
+		supply_name = kstrdup_const(supply_name, GFP_KERNEL);
+		if (supply_name == NULL)
+			return NULL;
+	}
+
+	regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
+	if (regulator == NULL) {
+		kfree_const(supply_name);
+		return NULL;
+	}
+
+	regulator->rdev = rdev;
+	regulator->supply_name = supply_name;
+
+	list_add(&regulator->list, &rdev->consumer_list);
+
+	if (dev) {
+		regulator->dev = dev;
+
+		/* Add a link to the device sysfs entry */
+		err = sysfs_create_link_nowarn(&rdev->dev.kobj, &dev->kobj,
+					       supply_name);
+		if (err) {
+			rdev_dbg(rdev, "could not add device link %s: %pe\n",
+				  dev->kobj.name, ERR_PTR(err));
+			/* non-fatal */
+		}
+	}
+
+	if (err != -EEXIST)
+		regulator->debugfs = debugfs_create_dir(supply_name, rdev->debugfs);
+	if (IS_ERR(regulator->debugfs))
+		rdev_dbg(rdev, "Failed to create debugfs directory\n");
+
+	debugfs_create_u32("uA_load", 0444, regulator->debugfs,
+			   &regulator->uA_load);
+	debugfs_create_u32("min_uV", 0444, regulator->debugfs,
+			   &regulator->voltage[PM_SUSPEND_ON].min_uV);
+	debugfs_create_u32("max_uV", 0444, regulator->debugfs,
+			   &regulator->voltage[PM_SUSPEND_ON].max_uV);
+	debugfs_create_file("constraint_flags", 0444, regulator->debugfs,
+			    regulator, &constraint_flags_fops);
+
+	/*
+	 * Check now if the regulator is an always on regulator - if
+	 * it is then we don't need to do nearly so much work for
+	 * enable/disable calls.
+	 */
+	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_STATUS) &&
+	    _regulator_is_enabled(rdev))
+		regulator->always_on = true;
+
+	return regulator;
+}
+
+static int _regulator_get_enable_time(struct regulator_dev *rdev)
+{
+	if (rdev->constraints && rdev->constraints->enable_time)
+		return rdev->constraints->enable_time;
+	if (rdev->desc->ops->enable_time)
+		return rdev->desc->ops->enable_time(rdev);
+	return rdev->desc->enable_time;
+}
+
+static struct regulator_supply_alias *regulator_find_supply_alias(
+		struct device *dev, const char *supply)
+{
+	struct regulator_supply_alias *map;
+
+	list_for_each_entry(map, &regulator_supply_alias_list, list)
+		if (map->src_dev == dev && strcmp(map->src_supply, supply) == 0)
+			return map;
+
+	return NULL;
+}
+
+static void regulator_supply_alias(struct device **dev, const char **supply)
+{
+	struct regulator_supply_alias *map;
+
+	map = regulator_find_supply_alias(*dev, *supply);
+	if (map) {
+		dev_dbg(*dev, "Mapping supply %s to %s,%s\n",
+				*supply, map->alias_supply,
+				dev_name(map->alias_dev));
+		*dev = map->alias_dev;
+		*supply = map->alias_supply;
+	}
+}
+
+static int regulator_match(struct device *dev, const void *data)
+{
+	struct regulator_dev *r = dev_to_rdev(dev);
+
+	return strcmp(rdev_get_name(r), data) == 0;
+}
+
+static struct regulator_dev *regulator_lookup_by_name(const char *name)
+{
+	struct device *dev;
+
+	dev = class_find_device(&regulator_class, NULL, name, regulator_match);
+
+	return dev ? dev_to_rdev(dev) : NULL;
+}
+
+/**
+ * regulator_dev_lookup - lookup a regulator device.
+ * @dev: device for regulator "consumer".
+ * @supply: Supply name or regulator ID.
+ *
+ * If successful, returns a struct regulator_dev that corresponds to the name
+ * @supply and with the embedded struct device refcount incremented by one.
+ * The refcount must be dropped by calling put_device().
+ * On failure one of the following ERR-PTR-encoded values is returned:
+ * -ENODEV if lookup fails permanently, -EPROBE_DEFER if lookup could succeed
+ * in the future.
+ */
+static struct regulator_dev *regulator_dev_lookup(struct device *dev,
+						  const char *supply)
+{
+	struct regulator_dev *r = NULL;
+	struct device_node *node;
+	struct regulator_map *map;
+	const char *devname = NULL;
+
+	regulator_supply_alias(&dev, &supply);
+
+	/* first do a dt based lookup */
+	if (dev && dev->of_node) {
+		node = of_get_regulator(dev, supply);
+		if (node) {
+			r = of_find_regulator_by_node(node);
+			of_node_put(node);
+			if (r)
+				return r;
+
+			/*
+			 * We have a node, but there is no device.
+			 * assume it has not registered yet.
+			 */
+			return ERR_PTR(-EPROBE_DEFER);
+		}
+	}
+
+	/* if not found, try doing it non-dt way */
+	if (dev)
+		devname = dev_name(dev);
+
+	mutex_lock(&regulator_list_mutex);
+	list_for_each_entry(map, &regulator_map_list, list) {
+		/* If the mapping has a device set up it must match */
+		if (map->dev_name &&
+		    (!devname || strcmp(map->dev_name, devname)))
+			continue;
+
+		if (strcmp(map->supply, supply) == 0 &&
+		    get_device(&map->regulator->dev)) {
+			r = map->regulator;
+			break;
+		}
+	}
+	mutex_unlock(&regulator_list_mutex);
+
+	if (r)
+		return r;
+
+	r = regulator_lookup_by_name(supply);
+	if (r)
+		return r;
+
+	return ERR_PTR(-ENODEV);
+}
+
+static int regulator_resolve_supply(struct regulator_dev *rdev)
+{
+	struct regulator_dev *r;
+	struct device *dev = rdev->dev.parent;
+	struct ww_acquire_ctx ww_ctx;
+	int ret = 0;
+
+	/* No supply to resolve? */
+	if (!rdev->supply_name)
+		return 0;
+
+	/* Supply already resolved? (fast-path without locking contention) */
+	if (rdev->supply)
+		return 0;
+
+	r = regulator_dev_lookup(dev, rdev->supply_name);
+	if (IS_ERR(r)) {
+		ret = PTR_ERR(r);
+
+		/* Did the lookup explicitly defer for us? */
+		if (ret == -EPROBE_DEFER)
+			goto out;
+
+		if (have_full_constraints()) {
+			r = dummy_regulator_rdev;
+			get_device(&r->dev);
+		} else {
+			dev_err(dev, "Failed to resolve %s-supply for %s\n",
+				rdev->supply_name, rdev->desc->name);
+			ret = -EPROBE_DEFER;
+			goto out;
+		}
+	}
+
+	if (r == rdev) {
+		dev_err(dev, "Supply for %s (%s) resolved to itself\n",
+			rdev->desc->name, rdev->supply_name);
+		if (!have_full_constraints()) {
+			ret = -EINVAL;
+			goto out;
+		}
+		r = dummy_regulator_rdev;
+		get_device(&r->dev);
+	}
+
+	/*
+	 * If the supply's parent device is not the same as the
+	 * regulator's parent device, then ensure the parent device
+	 * is bound before we resolve the supply, in case the parent
+	 * device get probe deferred and unregisters the supply.
+	 */
+	if (r->dev.parent && r->dev.parent != rdev->dev.parent) {
+		if (!device_is_bound(r->dev.parent)) {
+			put_device(&r->dev);
+			ret = -EPROBE_DEFER;
+			goto out;
+		}
+	}
+
+	/* Recursively resolve the supply of the supply */
+	ret = regulator_resolve_supply(r);
+	if (ret < 0) {
+		put_device(&r->dev);
+		goto out;
+	}
+
+	/*
+	 * Recheck rdev->supply with rdev->mutex lock held to avoid a race
+	 * between rdev->supply null check and setting rdev->supply in
+	 * set_supply() from concurrent tasks.
+	 */
+	regulator_lock_two(rdev, r, &ww_ctx);
+
+	/* Supply just resolved by a concurrent task? */
+	if (rdev->supply) {
+		regulator_unlock_two(rdev, r, &ww_ctx);
+		put_device(&r->dev);
+		goto out;
+	}
+
+	ret = set_supply(rdev, r);
+	if (ret < 0) {
+		regulator_unlock_two(rdev, r, &ww_ctx);
+		put_device(&r->dev);
+		goto out;
+	}
+
+	regulator_unlock_two(rdev, r, &ww_ctx);
+
+	/*
+	 * In set_machine_constraints() we may have turned this regulator on
+	 * but we couldn't propagate to the supply if it hadn't been resolved
+	 * yet.  Do it now.
+	 */
+	if (rdev->use_count) {
+		ret = regulator_enable(rdev->supply);
+		if (ret < 0) {
+			_regulator_put(rdev->supply);
+			rdev->supply = NULL;
+			goto out;
+		}
+	}
+
+out:
+	return ret;
+}
+
+/* Internal regulator request function */
+struct regulator *_regulator_get(struct device *dev, const char *id,
+				 enum regulator_get_type get_type)
+{
+	struct regulator_dev *rdev;
+	struct regulator *regulator;
+	struct device_link *link;
+	int ret;
+
+	if (get_type >= MAX_GET_TYPE) {
+		dev_err(dev, "invalid type %d in %s\n", get_type, __func__);
+		return ERR_PTR(-EINVAL);
+	}
+
+	if (id == NULL) {
+		pr_err("get() with no identifier\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	rdev = regulator_dev_lookup(dev, id);
+	if (IS_ERR(rdev)) {
+		ret = PTR_ERR(rdev);
+
+		/*
+		 * If regulator_dev_lookup() fails with error other
+		 * than -ENODEV our job here is done, we simply return it.
+		 */
+		if (ret != -ENODEV)
+			return ERR_PTR(ret);
+
+		if (!have_full_constraints()) {
+			dev_warn(dev,
+				 "incomplete constraints, dummy supplies not allowed\n");
+			return ERR_PTR(-ENODEV);
+		}
+
+		switch (get_type) {
+		case NORMAL_GET:
+			/*
+			 * Assume that a regulator is physically present and
+			 * enabled, even if it isn't hooked up, and just
+			 * provide a dummy.
+			 */
+			dev_warn(dev, "supply %s not found, using dummy regulator\n", id);
+			rdev = dummy_regulator_rdev;
+			get_device(&rdev->dev);
+			break;
+
+		case EXCLUSIVE_GET:
+			dev_warn(dev,
+				 "dummy supplies not allowed for exclusive requests\n");
+			fallthrough;
+
+		default:
+			return ERR_PTR(-ENODEV);
+		}
+	}
+
+	if (rdev->exclusive) {
+		regulator = ERR_PTR(-EPERM);
+		put_device(&rdev->dev);
+		return regulator;
+	}
+
+	if (get_type == EXCLUSIVE_GET && rdev->open_count) {
+		regulator = ERR_PTR(-EBUSY);
+		put_device(&rdev->dev);
+		return regulator;
+	}
+
+	mutex_lock(&regulator_list_mutex);
+	ret = (rdev->coupling_desc.n_resolved != rdev->coupling_desc.n_coupled);
+	mutex_unlock(&regulator_list_mutex);
+
+	if (ret != 0) {
+		regulator = ERR_PTR(-EPROBE_DEFER);
+		put_device(&rdev->dev);
+		return regulator;
+	}
+
+	ret = regulator_resolve_supply(rdev);
+	if (ret < 0) {
+		regulator = ERR_PTR(ret);
+		put_device(&rdev->dev);
+		return regulator;
+	}
+
+	if (!try_module_get(rdev->owner)) {
+		regulator = ERR_PTR(-EPROBE_DEFER);
+		put_device(&rdev->dev);
+		return regulator;
+	}
+
+	regulator_lock(rdev);
+	regulator = create_regulator(rdev, dev, id);
+	regulator_unlock(rdev);
+	if (regulator == NULL) {
+		regulator = ERR_PTR(-ENOMEM);
+		module_put(rdev->owner);
+		put_device(&rdev->dev);
+		return regulator;
+	}
+
+	rdev->open_count++;
+	if (get_type == EXCLUSIVE_GET) {
+		rdev->exclusive = 1;
+
+		ret = _regulator_is_enabled(rdev);
+		if (ret > 0) {
+			rdev->use_count = 1;
+			regulator->enable_count = 1;
+		} else {
+			rdev->use_count = 0;
+			regulator->enable_count = 0;
+		}
+	}
+
+	link = device_link_add(dev, &rdev->dev, DL_FLAG_STATELESS);
+	if (!IS_ERR_OR_NULL(link))
+		regulator->device_link = true;
+
+	return regulator;
+}
+
+/**
+ * regulator_get - lookup and obtain a reference to a regulator.
+ * @dev: device for regulator "consumer"
+ * @id: Supply name or regulator ID.
+ *
+ * Returns a struct regulator corresponding to the regulator producer,
+ * or IS_ERR() condition containing errno.
+ *
+ * Use of supply names configured via regulator_set_device_supply() is
+ * strongly encouraged.  It is recommended that the supply name used
+ * should match the name used for the supply and/or the relevant
+ * device pins in the datasheet.
+ */
+struct regulator *regulator_get(struct device *dev, const char *id)
+{
+	return _regulator_get(dev, id, NORMAL_GET);
+}
+EXPORT_SYMBOL_GPL(regulator_get);
+
+/**
+ * regulator_get_exclusive - obtain exclusive access to a regulator.
+ * @dev: device for regulator "consumer"
+ * @id: Supply name or regulator ID.
+ *
+ * Returns a struct regulator corresponding to the regulator producer,
+ * or IS_ERR() condition containing errno.  Other consumers will be
+ * unable to obtain this regulator while this reference is held and the
+ * use count for the regulator will be initialised to reflect the current
+ * state of the regulator.
+ *
+ * This is intended for use by consumers which cannot tolerate shared
+ * use of the regulator such as those which need to force the
+ * regulator off for correct operation of the hardware they are
+ * controlling.
+ *
+ * Use of supply names configured via regulator_set_device_supply() is
+ * strongly encouraged.  It is recommended that the supply name used
+ * should match the name used for the supply and/or the relevant
+ * device pins in the datasheet.
+ */
+struct regulator *regulator_get_exclusive(struct device *dev, const char *id)
+{
+	return _regulator_get(dev, id, EXCLUSIVE_GET);
+}
+EXPORT_SYMBOL_GPL(regulator_get_exclusive);
+
+/**
+ * regulator_get_optional - obtain optional access to a regulator.
+ * @dev: device for regulator "consumer"
+ * @id: Supply name or regulator ID.
+ *
+ * Returns a struct regulator corresponding to the regulator producer,
+ * or IS_ERR() condition containing errno.
+ *
+ * This is intended for use by consumers for devices which can have
+ * some supplies unconnected in normal use, such as some MMC devices.
+ * It can allow the regulator core to provide stub supplies for other
+ * supplies requested using normal regulator_get() calls without
+ * disrupting the operation of drivers that can handle absent
+ * supplies.
+ *
+ * Use of supply names configured via regulator_set_device_supply() is
+ * strongly encouraged.  It is recommended that the supply name used
+ * should match the name used for the supply and/or the relevant
+ * device pins in the datasheet.
+ */
+struct regulator *regulator_get_optional(struct device *dev, const char *id)
+{
+	return _regulator_get(dev, id, OPTIONAL_GET);
+}
+EXPORT_SYMBOL_GPL(regulator_get_optional);
+
+static void destroy_regulator(struct regulator *regulator)
+{
+	struct regulator_dev *rdev = regulator->rdev;
+
+	debugfs_remove_recursive(regulator->debugfs);
+
+	if (regulator->dev) {
+		if (regulator->device_link)
+			device_link_remove(regulator->dev, &rdev->dev);
+
+		/* remove any sysfs entries */
+		sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
+	}
+
+	regulator_lock(rdev);
+	list_del(&regulator->list);
+
+	rdev->open_count--;
+	rdev->exclusive = 0;
+	regulator_unlock(rdev);
+
+	kfree_const(regulator->supply_name);
+	kfree(regulator);
+}
+
+/* regulator_list_mutex lock held by regulator_put() */
+static void _regulator_put(struct regulator *regulator)
+{
+	struct regulator_dev *rdev;
+
+	if (IS_ERR_OR_NULL(regulator))
+		return;
+
+	lockdep_assert_held_once(&regulator_list_mutex);
+
+	/* Docs say you must disable before calling regulator_put() */
+	WARN_ON(regulator->enable_count);
+
+	rdev = regulator->rdev;
+
+	destroy_regulator(regulator);
+
+	module_put(rdev->owner);
+	put_device(&rdev->dev);
+}
+
+/**
+ * regulator_put - "free" the regulator source
+ * @regulator: regulator source
+ *
+ * Note: drivers must ensure that all regulator_enable calls made on this
+ * regulator source are balanced by regulator_disable calls prior to calling
+ * this function.
+ */
+void regulator_put(struct regulator *regulator)
+{
+	mutex_lock(&regulator_list_mutex);
+	_regulator_put(regulator);
+	mutex_unlock(&regulator_list_mutex);
+}
+EXPORT_SYMBOL_GPL(regulator_put);
+
+/**
+ * regulator_register_supply_alias - Provide device alias for supply lookup
+ *
+ * @dev: device that will be given as the regulator "consumer"
+ * @id: Supply name or regulator ID
+ * @alias_dev: device that should be used to lookup the supply
+ * @alias_id: Supply name or regulator ID that should be used to lookup the
+ * supply
+ *
+ * All lookups for id on dev will instead be conducted for alias_id on
+ * alias_dev.
+ */
+int regulator_register_supply_alias(struct device *dev, const char *id,
+				    struct device *alias_dev,
+				    const char *alias_id)
+{
+	struct regulator_supply_alias *map;
+
+	map = regulator_find_supply_alias(dev, id);
+	if (map)
+		return -EEXIST;
+
+	map = kzalloc(sizeof(struct regulator_supply_alias), GFP_KERNEL);
+	if (!map)
+		return -ENOMEM;
+
+	map->src_dev = dev;
+	map->src_supply = id;
+	map->alias_dev = alias_dev;
+	map->alias_supply = alias_id;
+
+	list_add(&map->list, &regulator_supply_alias_list);
+
+	pr_info("Adding alias for supply %s,%s -> %s,%s\n",
+		id, dev_name(dev), alias_id, dev_name(alias_dev));
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(regulator_register_supply_alias);
+
+/**
+ * regulator_unregister_supply_alias - Remove device alias
+ *
+ * @dev: device that will be given as the regulator "consumer"
+ * @id: Supply name or regulator ID
+ *
+ * Remove a lookup alias if one exists for id on dev.
+ */
+void regulator_unregister_supply_alias(struct device *dev, const char *id)
+{
+	struct regulator_supply_alias *map;
+
+	map = regulator_find_supply_alias(dev, id);
+	if (map) {
+		list_del(&map->list);
+		kfree(map);
+	}
+}
+EXPORT_SYMBOL_GPL(regulator_unregister_supply_alias);
+
+/**
+ * regulator_bulk_register_supply_alias - register multiple aliases
+ *
+ * @dev: device that will be given as the regulator "consumer"
+ * @id: List of supply names or regulator IDs
+ * @alias_dev: device that should be used to lookup the supply
+ * @alias_id: List of supply names or regulator IDs that should be used to
+ * lookup the supply
+ * @num_id: Number of aliases to register
+ *
+ * @return 0 on success, an errno on failure.
+ *
+ * This helper function allows drivers to register several supply
+ * aliases in one operation.  If any of the aliases cannot be
+ * registered any aliases that were registered will be removed
+ * before returning to the caller.
+ */
+int regulator_bulk_register_supply_alias(struct device *dev,
+					 const char *const *id,
+					 struct device *alias_dev,
+					 const char *const *alias_id,
+					 int num_id)
+{
+	int i;
+	int ret;
+
+	for (i = 0; i < num_id; ++i) {
+		ret = regulator_register_supply_alias(dev, id[i], alias_dev,
+						      alias_id[i]);
+		if (ret < 0)
+			goto err;
+	}
+
+	return 0;
+
+err:
+	dev_err(dev,
+		"Failed to create supply alias %s,%s -> %s,%s\n",
+		id[i], dev_name(dev), alias_id[i], dev_name(alias_dev));
+
+	while (--i >= 0)
+		regulator_unregister_supply_alias(dev, id[i]);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_bulk_register_supply_alias);
+
+/**
+ * regulator_bulk_unregister_supply_alias - unregister multiple aliases
+ *
+ * @dev: device that will be given as the regulator "consumer"
+ * @id: List of supply names or regulator IDs
+ * @num_id: Number of aliases to unregister
+ *
+ * This helper function allows drivers to unregister several supply
+ * aliases in one operation.
+ */
+void regulator_bulk_unregister_supply_alias(struct device *dev,
+					    const char *const *id,
+					    int num_id)
+{
+	int i;
+
+	for (i = 0; i < num_id; ++i)
+		regulator_unregister_supply_alias(dev, id[i]);
+}
+EXPORT_SYMBOL_GPL(regulator_bulk_unregister_supply_alias);
+
+
+/* Manage enable GPIO list. Same GPIO pin can be shared among regulators */
+static int regulator_ena_gpio_request(struct regulator_dev *rdev,
+				const struct regulator_config *config)
+{
+	struct regulator_enable_gpio *pin, *new_pin;
+	struct gpio_desc *gpiod;
+
+	gpiod = config->ena_gpiod;
+	new_pin = kzalloc(sizeof(*new_pin), GFP_KERNEL);
+
+	mutex_lock(&regulator_list_mutex);
+
+	list_for_each_entry(pin, &regulator_ena_gpio_list, list) {
+		if (pin->gpiod == gpiod) {
+			rdev_dbg(rdev, "GPIO is already used\n");
+			goto update_ena_gpio_to_rdev;
+		}
+	}
+
+	if (new_pin == NULL) {
+		mutex_unlock(&regulator_list_mutex);
+		return -ENOMEM;
+	}
+
+	pin = new_pin;
+	new_pin = NULL;
+
+	pin->gpiod = gpiod;
+	list_add(&pin->list, &regulator_ena_gpio_list);
+
+update_ena_gpio_to_rdev:
+	pin->request_count++;
+	rdev->ena_pin = pin;
+
+	mutex_unlock(&regulator_list_mutex);
+	kfree(new_pin);
+
+	return 0;
+}
+
+static void regulator_ena_gpio_free(struct regulator_dev *rdev)
+{
+	struct regulator_enable_gpio *pin, *n;
+
+	if (!rdev->ena_pin)
+		return;
+
+	/* Free the GPIO only in case of no use */
+	list_for_each_entry_safe(pin, n, &regulator_ena_gpio_list, list) {
+		if (pin != rdev->ena_pin)
+			continue;
+
+		if (--pin->request_count)
+			break;
+
+		gpiod_put(pin->gpiod);
+		list_del(&pin->list);
+		kfree(pin);
+		break;
+	}
+
+	rdev->ena_pin = NULL;
+}
+
+/**
+ * regulator_ena_gpio_ctrl - balance enable_count of each GPIO and actual GPIO pin control
+ * @rdev: regulator_dev structure
+ * @enable: enable GPIO at initial use?
+ *
+ * GPIO is enabled in case of initial use. (enable_count is 0)
+ * GPIO is disabled when it is not shared any more. (enable_count <= 1)
+ */
+static int regulator_ena_gpio_ctrl(struct regulator_dev *rdev, bool enable)
+{
+	struct regulator_enable_gpio *pin = rdev->ena_pin;
+
+	if (!pin)
+		return -EINVAL;
+
+	if (enable) {
+		/* Enable GPIO at initial use */
+		if (pin->enable_count == 0)
+			gpiod_set_value_cansleep(pin->gpiod, 1);
+
+		pin->enable_count++;
+	} else {
+		if (pin->enable_count > 1) {
+			pin->enable_count--;
+			return 0;
+		}
+
+		/* Disable GPIO if not used */
+		if (pin->enable_count <= 1) {
+			gpiod_set_value_cansleep(pin->gpiod, 0);
+			pin->enable_count = 0;
+		}
+	}
+
+	return 0;
+}
+
+/**
+ * _regulator_enable_delay - a delay helper function
+ * @delay: time to delay in microseconds
+ *
+ * Delay for the requested amount of time as per the guidelines in:
+ *
+ *     Documentation/timers/timers-howto.rst
+ *
+ * The assumption here is that regulators will never be enabled in
+ * atomic context and therefore sleeping functions can be used.
+ */
+static void _regulator_enable_delay(unsigned int delay)
+{
+	unsigned int ms = delay / 1000;
+	unsigned int us = delay % 1000;
+
+	if (ms > 0) {
+		/*
+		 * For small enough values, handle super-millisecond
+		 * delays in the usleep_range() call below.
+		 */
+		if (ms < 20)
+			us += ms * 1000;
+		else
+			msleep(ms);
+	}
+
+	/*
+	 * Give the scheduler some room to coalesce with any other
+	 * wakeup sources. For delays shorter than 10 us, don't even
+	 * bother setting up high-resolution timers and just busy-
+	 * loop.
+	 */
+	if (us >= 10)
+		usleep_range(us, us + 100);
+	else
+		udelay(us);
+}
+
+/**
+ * _regulator_check_status_enabled
+ *
+ * A helper function to check if the regulator status can be interpreted
+ * as 'regulator is enabled'.
+ * @rdev: the regulator device to check
+ *
+ * Return:
+ * * 1			- if status shows regulator is in enabled state
+ * * 0			- if not enabled state
+ * * Error Value	- as received from ops->get_status()
+ */
+static inline int _regulator_check_status_enabled(struct regulator_dev *rdev)
+{
+	int ret = rdev->desc->ops->get_status(rdev);
+
+	if (ret < 0) {
+		rdev_info(rdev, "get_status returned error: %d\n", ret);
+		return ret;
+	}
+
+	switch (ret) {
+	case REGULATOR_STATUS_OFF:
+	case REGULATOR_STATUS_ERROR:
+	case REGULATOR_STATUS_UNDEFINED:
+		return 0;
+	default:
+		return 1;
+	}
+}
+
+static int _regulator_do_enable(struct regulator_dev *rdev)
+{
+	int ret, delay;
+
+	/* Query before enabling in case configuration dependent.  */
+	ret = _regulator_get_enable_time(rdev);
+	if (ret >= 0) {
+		delay = ret;
+	} else {
+		rdev_warn(rdev, "enable_time() failed: %pe\n", ERR_PTR(ret));
+		delay = 0;
+	}
+
+	trace_regulator_enable(rdev_get_name(rdev));
+
+	if (rdev->desc->off_on_delay) {
+		/* if needed, keep a distance of off_on_delay from last time
+		 * this regulator was disabled.
+		 */
+		unsigned long start_jiffy = jiffies;
+		unsigned long intended, max_delay, remaining;
+
+		max_delay = usecs_to_jiffies(rdev->desc->off_on_delay);
+		intended = rdev->last_off_jiffy + max_delay;
+
+		if (time_before(start_jiffy, intended)) {
+			/* calc remaining jiffies to deal with one-time
+			 * timer wrapping.
+			 * in case of multiple timer wrapping, either it can be
+			 * detected by out-of-range remaining, or it cannot be
+			 * detected and we get a penalty of
+			 * _regulator_enable_delay().
+			 */
+			remaining = intended - start_jiffy;
+			if (remaining <= max_delay)
+				_regulator_enable_delay(
+						jiffies_to_usecs(remaining));
+		}
+	}
+
+	if (rdev->ena_pin) {
+		if (!rdev->ena_gpio_state) {
+			ret = regulator_ena_gpio_ctrl(rdev, true);
+			if (ret < 0)
+				return ret;
+			rdev->ena_gpio_state = 1;
+		}
+	} else if (rdev->desc->ops->enable) {
+		ret = rdev->desc->ops->enable(rdev);
+		if (ret < 0)
+			return ret;
+	} else {
+		return -EINVAL;
+	}
+
+	/* Allow the regulator to ramp; it would be useful to extend
+	 * this for bulk operations so that the regulators can ramp
+	 * together.  */
+	trace_regulator_enable_delay(rdev_get_name(rdev));
+
+	/* If poll_enabled_time is set, poll upto the delay calculated
+	 * above, delaying poll_enabled_time uS to check if the regulator
+	 * actually got enabled.
+	 * If the regulator isn't enabled after enable_delay has
+	 * expired, return -ETIMEDOUT.
+	 */
+	if (rdev->desc->poll_enabled_time) {
+		int time_remaining = delay;
+
+		while (time_remaining > 0) {
+			_regulator_enable_delay(rdev->desc->poll_enabled_time);
+
+			if (rdev->desc->ops->get_status) {
+				ret = _regulator_check_status_enabled(rdev);
+				if (ret < 0)
+					return ret;
+				else if (ret)
+					break;
+			} else if (rdev->desc->ops->is_enabled(rdev))
+				break;
+
+			time_remaining -= rdev->desc->poll_enabled_time;
+		}
+
+		if (time_remaining <= 0) {
+			rdev_err(rdev, "Enabled check timed out\n");
+			return -ETIMEDOUT;
+		}
+	} else {
+		_regulator_enable_delay(delay);
+	}
+
+	trace_regulator_enable_complete(rdev_get_name(rdev));
+
+	return 0;
+}
+
+/**
+ * _regulator_handle_consumer_enable - handle that a consumer enabled
+ * @regulator: regulator source
+ *
+ * Some things on a regulator consumer (like the contribution towards total
+ * load on the regulator) only have an effect when the consumer wants the
+ * regulator enabled.  Explained in example with two consumers of the same
+ * regulator:
+ *   consumer A: set_load(100);       => total load = 0
+ *   consumer A: regulator_enable();  => total load = 100
+ *   consumer B: set_load(1000);      => total load = 100
+ *   consumer B: regulator_enable();  => total load = 1100
+ *   consumer A: regulator_disable(); => total_load = 1000
+ *
+ * This function (together with _regulator_handle_consumer_disable) is
+ * responsible for keeping track of the refcount for a given regulator consumer
+ * and applying / unapplying these things.
+ *
+ * Returns 0 upon no error; -error upon error.
+ */
+static int _regulator_handle_consumer_enable(struct regulator *regulator)
+{
+	int ret;
+	struct regulator_dev *rdev = regulator->rdev;
+
+	lockdep_assert_held_once(&rdev->mutex.base);
+
+	regulator->enable_count++;
+	if (regulator->uA_load && regulator->enable_count == 1) {
+		ret = drms_uA_update(rdev);
+		if (ret)
+			regulator->enable_count--;
+		return ret;
+	}
+
+	return 0;
+}
+
+/**
+ * _regulator_handle_consumer_disable - handle that a consumer disabled
+ * @regulator: regulator source
+ *
+ * The opposite of _regulator_handle_consumer_enable().
+ *
+ * Returns 0 upon no error; -error upon error.
+ */
+static int _regulator_handle_consumer_disable(struct regulator *regulator)
+{
+	struct regulator_dev *rdev = regulator->rdev;
+
+	lockdep_assert_held_once(&rdev->mutex.base);
+
+	if (!regulator->enable_count) {
+		rdev_err(rdev, "Underflow of regulator enable count\n");
+		return -EINVAL;
+	}
+
+	regulator->enable_count--;
+	if (regulator->uA_load && regulator->enable_count == 0)
+		return drms_uA_update(rdev);
+
+	return 0;
+}
+
+/* locks held by regulator_enable() */
+static int _regulator_enable(struct regulator *regulator)
+{
+	struct regulator_dev *rdev = regulator->rdev;
+	int ret;
+
+	lockdep_assert_held_once(&rdev->mutex.base);
+
+	if (rdev->use_count == 0 && rdev->supply) {
+		ret = _regulator_enable(rdev->supply);
+		if (ret < 0)
+			return ret;
+	}
+
+	/* balance only if there are regulators coupled */
+	if (rdev->coupling_desc.n_coupled > 1) {
+		ret = regulator_balance_voltage(rdev, PM_SUSPEND_ON);
+		if (ret < 0)
+			goto err_disable_supply;
+	}
+
+	ret = _regulator_handle_consumer_enable(regulator);
+	if (ret < 0)
+		goto err_disable_supply;
+
+	if (rdev->use_count == 0) {
+		/* The regulator may on if it's not switchable or left on */
+		ret = _regulator_is_enabled(rdev);
+		if (ret == -EINVAL || ret == 0) {
+			if (!regulator_ops_is_valid(rdev,
+					REGULATOR_CHANGE_STATUS)) {
+				ret = -EPERM;
+				goto err_consumer_disable;
+			}
+
+			ret = _regulator_do_enable(rdev);
+			if (ret < 0)
+				goto err_consumer_disable;
+
+			_notifier_call_chain(rdev, REGULATOR_EVENT_ENABLE,
+					     NULL);
+		} else if (ret < 0) {
+			rdev_err(rdev, "is_enabled() failed: %pe\n", ERR_PTR(ret));
+			goto err_consumer_disable;
+		}
+		/* Fallthrough on positive return values - already enabled */
+	}
+
+	rdev->use_count++;
+
+	return 0;
+
+err_consumer_disable:
+	_regulator_handle_consumer_disable(regulator);
+
+err_disable_supply:
+	if (rdev->use_count == 0 && rdev->supply)
+		_regulator_disable(rdev->supply);
+
+	return ret;
+}
+
+/**
+ * regulator_enable - enable regulator output
+ * @regulator: regulator source
+ *
+ * Request that the regulator be enabled with the regulator output at
+ * the predefined voltage or current value.  Calls to regulator_enable()
+ * must be balanced with calls to regulator_disable().
+ *
+ * NOTE: the output value can be set by other drivers, boot loader or may be
+ * hardwired in the regulator.
+ */
+int regulator_enable(struct regulator *regulator)
+{
+	struct regulator_dev *rdev = regulator->rdev;
+	struct ww_acquire_ctx ww_ctx;
+	int ret;
+
+	regulator_lock_dependent(rdev, &ww_ctx);
+	ret = _regulator_enable(regulator);
+	regulator_unlock_dependent(rdev, &ww_ctx);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_enable);
+
+static int _regulator_do_disable(struct regulator_dev *rdev)
+{
+	int ret;
+
+	trace_regulator_disable(rdev_get_name(rdev));
+
+	if (rdev->ena_pin) {
+		if (rdev->ena_gpio_state) {
+			ret = regulator_ena_gpio_ctrl(rdev, false);
+			if (ret < 0)
+				return ret;
+			rdev->ena_gpio_state = 0;
+		}
+
+	} else if (rdev->desc->ops->disable) {
+		ret = rdev->desc->ops->disable(rdev);
+		if (ret != 0)
+			return ret;
+	}
+
+	/* cares about last_off_jiffy only if off_on_delay is required by
+	 * device.
+	 */
+	if (rdev->desc->off_on_delay)
+		rdev->last_off_jiffy = jiffies;
+
+	trace_regulator_disable_complete(rdev_get_name(rdev));
+
+	return 0;
+}
+
+/* locks held by regulator_disable() */
+static int _regulator_disable(struct regulator *regulator)
+{
+	struct regulator_dev *rdev = regulator->rdev;
+	int ret = 0;
+
+	lockdep_assert_held_once(&rdev->mutex.base);
+
+	if (WARN(rdev->use_count <= 0,
+		 "unbalanced disables for %s\n", rdev_get_name(rdev)))
+		return -EIO;
+
+	/* are we the last user and permitted to disable ? */
+	if (rdev->use_count == 1 &&
+	    (rdev->constraints && !rdev->constraints->always_on)) {
+
+		/* we are last user */
+		if (regulator_ops_is_valid(rdev, REGULATOR_CHANGE_STATUS)) {
+			ret = _notifier_call_chain(rdev,
+						   REGULATOR_EVENT_PRE_DISABLE,
+						   NULL);
+			if (ret & NOTIFY_STOP_MASK)
+				return -EINVAL;
+
+			ret = _regulator_do_disable(rdev);
+			if (ret < 0) {
+				rdev_err(rdev, "failed to disable: %pe\n", ERR_PTR(ret));
+				_notifier_call_chain(rdev,
+						REGULATOR_EVENT_ABORT_DISABLE,
+						NULL);
+				return ret;
+			}
+			_notifier_call_chain(rdev, REGULATOR_EVENT_DISABLE,
+					NULL);
+		}
+
+		rdev->use_count = 0;
+	} else if (rdev->use_count > 1) {
+		rdev->use_count--;
+	}
+
+	if (ret == 0)
+		ret = _regulator_handle_consumer_disable(regulator);
+
+	if (ret == 0 && rdev->coupling_desc.n_coupled > 1)
+		ret = regulator_balance_voltage(rdev, PM_SUSPEND_ON);
+
+	if (ret == 0 && rdev->use_count == 0 && rdev->supply)
+		ret = _regulator_disable(rdev->supply);
+
+	return ret;
+}
+
+/**
+ * regulator_disable - disable regulator output
+ * @regulator: regulator source
+ *
+ * Disable the regulator output voltage or current.  Calls to
+ * regulator_enable() must be balanced with calls to
+ * regulator_disable().
+ *
+ * NOTE: this will only disable the regulator output if no other consumer
+ * devices have it enabled, the regulator device supports disabling and
+ * machine constraints permit this operation.
+ */
+int regulator_disable(struct regulator *regulator)
+{
+	struct regulator_dev *rdev = regulator->rdev;
+	struct ww_acquire_ctx ww_ctx;
+	int ret;
+
+	regulator_lock_dependent(rdev, &ww_ctx);
+	ret = _regulator_disable(regulator);
+	regulator_unlock_dependent(rdev, &ww_ctx);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_disable);
+
+/* locks held by regulator_force_disable() */
+static int _regulator_force_disable(struct regulator_dev *rdev)
+{
+	int ret = 0;
+
+	lockdep_assert_held_once(&rdev->mutex.base);
+
+	ret = _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
+			REGULATOR_EVENT_PRE_DISABLE, NULL);
+	if (ret & NOTIFY_STOP_MASK)
+		return -EINVAL;
+
+	ret = _regulator_do_disable(rdev);
+	if (ret < 0) {
+		rdev_err(rdev, "failed to force disable: %pe\n", ERR_PTR(ret));
+		_notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
+				REGULATOR_EVENT_ABORT_DISABLE, NULL);
+		return ret;
+	}
+
+	_notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
+			REGULATOR_EVENT_DISABLE, NULL);
+
+	return 0;
+}
+
+/**
+ * regulator_force_disable - force disable regulator output
+ * @regulator: regulator source
+ *
+ * Forcibly disable the regulator output voltage or current.
+ * NOTE: this *will* disable the regulator output even if other consumer
+ * devices have it enabled. This should be used for situations when device
+ * damage will likely occur if the regulator is not disabled (e.g. over temp).
+ */
+int regulator_force_disable(struct regulator *regulator)
+{
+	struct regulator_dev *rdev = regulator->rdev;
+	struct ww_acquire_ctx ww_ctx;
+	int ret;
+
+	regulator_lock_dependent(rdev, &ww_ctx);
+
+	ret = _regulator_force_disable(regulator->rdev);
+
+	if (rdev->coupling_desc.n_coupled > 1)
+		regulator_balance_voltage(rdev, PM_SUSPEND_ON);
+
+	if (regulator->uA_load) {
+		regulator->uA_load = 0;
+		ret = drms_uA_update(rdev);
+	}
+
+	if (rdev->use_count != 0 && rdev->supply)
+		_regulator_disable(rdev->supply);
+
+	regulator_unlock_dependent(rdev, &ww_ctx);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_force_disable);
+
+static void regulator_disable_work(struct work_struct *work)
+{
+	struct regulator_dev *rdev = container_of(work, struct regulator_dev,
+						  disable_work.work);
+	struct ww_acquire_ctx ww_ctx;
+	int count, i, ret;
+	struct regulator *regulator;
+	int total_count = 0;
+
+	regulator_lock_dependent(rdev, &ww_ctx);
+
+	/*
+	 * Workqueue functions queue the new work instance while the previous
+	 * work instance is being processed. Cancel the queued work instance
+	 * as the work instance under processing does the job of the queued
+	 * work instance.
+	 */
+	cancel_delayed_work(&rdev->disable_work);
+
+	list_for_each_entry(regulator, &rdev->consumer_list, list) {
+		count = regulator->deferred_disables;
+
+		if (!count)
+			continue;
+
+		total_count += count;
+		regulator->deferred_disables = 0;
+
+		for (i = 0; i < count; i++) {
+			ret = _regulator_disable(regulator);
+			if (ret != 0)
+				rdev_err(rdev, "Deferred disable failed: %pe\n",
+					 ERR_PTR(ret));
+		}
+	}
+	WARN_ON(!total_count);
+
+	if (rdev->coupling_desc.n_coupled > 1)
+		regulator_balance_voltage(rdev, PM_SUSPEND_ON);
+
+	regulator_unlock_dependent(rdev, &ww_ctx);
+}
+
+/**
+ * regulator_disable_deferred - disable regulator output with delay
+ * @regulator: regulator source
+ * @ms: milliseconds until the regulator is disabled
+ *
+ * Execute regulator_disable() on the regulator after a delay.  This
+ * is intended for use with devices that require some time to quiesce.
+ *
+ * NOTE: this will only disable the regulator output if no other consumer
+ * devices have it enabled, the regulator device supports disabling and
+ * machine constraints permit this operation.
+ */
+int regulator_disable_deferred(struct regulator *regulator, int ms)
+{
+	struct regulator_dev *rdev = regulator->rdev;
+
+	if (!ms)
+		return regulator_disable(regulator);
+
+	regulator_lock(rdev);
+	regulator->deferred_disables++;
+	mod_delayed_work(system_power_efficient_wq, &rdev->disable_work,
+			 msecs_to_jiffies(ms));
+	regulator_unlock(rdev);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(regulator_disable_deferred);
+
+static int _regulator_is_enabled(struct regulator_dev *rdev)
+{
+	/* A GPIO control always takes precedence */
+	if (rdev->ena_pin)
+		return rdev->ena_gpio_state;
+
+	/* If we don't know then assume that the regulator is always on */
+	if (!rdev->desc->ops->is_enabled)
+		return 1;
+
+	return rdev->desc->ops->is_enabled(rdev);
+}
+
+static int _regulator_list_voltage(struct regulator_dev *rdev,
+				   unsigned selector, int lock)
+{
+	const struct regulator_ops *ops = rdev->desc->ops;
+	int ret;
+
+	if (rdev->desc->fixed_uV && rdev->desc->n_voltages == 1 && !selector)
+		return rdev->desc->fixed_uV;
+
+	if (ops->list_voltage) {
+		if (selector >= rdev->desc->n_voltages)
+			return -EINVAL;
+		if (lock)
+			regulator_lock(rdev);
+		ret = ops->list_voltage(rdev, selector);
+		if (lock)
+			regulator_unlock(rdev);
+	} else if (rdev->is_switch && rdev->supply) {
+		ret = _regulator_list_voltage(rdev->supply->rdev,
+					      selector, lock);
+	} else {
+		return -EINVAL;
+	}
+
+	if (ret > 0) {
+		if (ret < rdev->constraints->min_uV)
+			ret = 0;
+		else if (ret > rdev->constraints->max_uV)
+			ret = 0;
+	}
+
+	return ret;
+}
+
+/**
+ * regulator_is_enabled - is the regulator output enabled
+ * @regulator: regulator source
+ *
+ * Returns positive if the regulator driver backing the source/client
+ * has requested that the device be enabled, zero if it hasn't, else a
+ * negative errno code.
+ *
+ * Note that the device backing this regulator handle can have multiple
+ * users, so it might be enabled even if regulator_enable() was never
+ * called for this particular source.
+ */
+int regulator_is_enabled(struct regulator *regulator)
+{
+	int ret;
+
+	if (regulator->always_on)
+		return 1;
+
+	regulator_lock(regulator->rdev);
+	ret = _regulator_is_enabled(regulator->rdev);
+	regulator_unlock(regulator->rdev);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_is_enabled);
+
+/**
+ * regulator_count_voltages - count regulator_list_voltage() selectors
+ * @regulator: regulator source
+ *
+ * Returns number of selectors, or negative errno.  Selectors are
+ * numbered starting at zero, and typically correspond to bitfields
+ * in hardware registers.
+ */
+int regulator_count_voltages(struct regulator *regulator)
+{
+	struct regulator_dev	*rdev = regulator->rdev;
+
+	if (rdev->desc->n_voltages)
+		return rdev->desc->n_voltages;
+
+	if (!rdev->is_switch || !rdev->supply)
+		return -EINVAL;
+
+	return regulator_count_voltages(rdev->supply);
+}
+EXPORT_SYMBOL_GPL(regulator_count_voltages);
+
+/**
+ * regulator_list_voltage - enumerate supported voltages
+ * @regulator: regulator source
+ * @selector: identify voltage to list
+ * Context: can sleep
+ *
+ * Returns a voltage that can be passed to @regulator_set_voltage(),
+ * zero if this selector code can't be used on this system, or a
+ * negative errno.
+ */
+int regulator_list_voltage(struct regulator *regulator, unsigned selector)
+{
+	return _regulator_list_voltage(regulator->rdev, selector, 1);
+}
+EXPORT_SYMBOL_GPL(regulator_list_voltage);
+
+/**
+ * regulator_get_regmap - get the regulator's register map
+ * @regulator: regulator source
+ *
+ * Returns the register map for the given regulator, or an ERR_PTR value
+ * if the regulator doesn't use regmap.
+ */
+struct regmap *regulator_get_regmap(struct regulator *regulator)
+{
+	struct regmap *map = regulator->rdev->regmap;
+
+	return map ? map : ERR_PTR(-EOPNOTSUPP);
+}
+
+/**
+ * regulator_get_hardware_vsel_register - get the HW voltage selector register
+ * @regulator: regulator source
+ * @vsel_reg: voltage selector register, output parameter
+ * @vsel_mask: mask for voltage selector bitfield, output parameter
+ *
+ * Returns the hardware register offset and bitmask used for setting the
+ * regulator voltage. This might be useful when configuring voltage-scaling
+ * hardware or firmware that can make I2C requests behind the kernel's back,
+ * for example.
+ *
+ * On success, the output parameters @vsel_reg and @vsel_mask are filled in
+ * and 0 is returned, otherwise a negative errno is returned.
+ */
+int regulator_get_hardware_vsel_register(struct regulator *regulator,
+					 unsigned *vsel_reg,
+					 unsigned *vsel_mask)
+{
+	struct regulator_dev *rdev = regulator->rdev;
+	const struct regulator_ops *ops = rdev->desc->ops;
+
+	if (ops->set_voltage_sel != regulator_set_voltage_sel_regmap)
+		return -EOPNOTSUPP;
+
+	*vsel_reg = rdev->desc->vsel_reg;
+	*vsel_mask = rdev->desc->vsel_mask;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(regulator_get_hardware_vsel_register);
+
+/**
+ * regulator_list_hardware_vsel - get the HW-specific register value for a selector
+ * @regulator: regulator source
+ * @selector: identify voltage to list
+ *
+ * Converts the selector to a hardware-specific voltage selector that can be
+ * directly written to the regulator registers. The address of the voltage
+ * register can be determined by calling @regulator_get_hardware_vsel_register.
+ *
+ * On error a negative errno is returned.
+ */
+int regulator_list_hardware_vsel(struct regulator *regulator,
+				 unsigned selector)
+{
+	struct regulator_dev *rdev = regulator->rdev;
+	const struct regulator_ops *ops = rdev->desc->ops;
+
+	if (selector >= rdev->desc->n_voltages)
+		return -EINVAL;
+	if (ops->set_voltage_sel != regulator_set_voltage_sel_regmap)
+		return -EOPNOTSUPP;
+
+	return selector;
+}
+EXPORT_SYMBOL_GPL(regulator_list_hardware_vsel);
+
+/**
+ * regulator_get_linear_step - return the voltage step size between VSEL values
+ * @regulator: regulator source
+ *
+ * Returns the voltage step size between VSEL values for linear
+ * regulators, or return 0 if the regulator isn't a linear regulator.
+ */
+unsigned int regulator_get_linear_step(struct regulator *regulator)
+{
+	struct regulator_dev *rdev = regulator->rdev;
+
+	return rdev->desc->uV_step;
+}
+EXPORT_SYMBOL_GPL(regulator_get_linear_step);
+
+/**
+ * regulator_is_supported_voltage - check if a voltage range can be supported
+ *
+ * @regulator: Regulator to check.
+ * @min_uV: Minimum required voltage in uV.
+ * @max_uV: Maximum required voltage in uV.
+ *
+ * Returns a boolean.
+ */
+int regulator_is_supported_voltage(struct regulator *regulator,
+				   int min_uV, int max_uV)
+{
+	struct regulator_dev *rdev = regulator->rdev;
+	int i, voltages, ret;
+
+	/* If we can't change voltage check the current voltage */
+	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE)) {
+		ret = regulator_get_voltage(regulator);
+		if (ret >= 0)
+			return min_uV <= ret && ret <= max_uV;
+		else
+			return ret;
+	}
+
+	/* Any voltage within constrains range is fine? */
+	if (rdev->desc->continuous_voltage_range)
+		return min_uV >= rdev->constraints->min_uV &&
+				max_uV <= rdev->constraints->max_uV;
+
+	ret = regulator_count_voltages(regulator);
+	if (ret < 0)
+		return 0;
+	voltages = ret;
+
+	for (i = 0; i < voltages; i++) {
+		ret = regulator_list_voltage(regulator, i);
+
+		if (ret >= min_uV && ret <= max_uV)
+			return 1;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(regulator_is_supported_voltage);
+
+static int regulator_map_voltage(struct regulator_dev *rdev, int min_uV,
+				 int max_uV)
+{
+	const struct regulator_desc *desc = rdev->desc;
+
+	if (desc->ops->map_voltage)
+		return desc->ops->map_voltage(rdev, min_uV, max_uV);
+
+	if (desc->ops->list_voltage == regulator_list_voltage_linear)
+		return regulator_map_voltage_linear(rdev, min_uV, max_uV);
+
+	if (desc->ops->list_voltage == regulator_list_voltage_linear_range)
+		return regulator_map_voltage_linear_range(rdev, min_uV, max_uV);
+
+	if (desc->ops->list_voltage ==
+		regulator_list_voltage_pickable_linear_range)
+		return regulator_map_voltage_pickable_linear_range(rdev,
+							min_uV, max_uV);
+
+	return regulator_map_voltage_iterate(rdev, min_uV, max_uV);
+}
+
+static int _regulator_call_set_voltage(struct regulator_dev *rdev,
+				       int min_uV, int max_uV,
+				       unsigned *selector)
+{
+	struct pre_voltage_change_data data;
+	int ret;
+
+	data.old_uV = regulator_get_voltage_rdev(rdev);
+	data.min_uV = min_uV;
+	data.max_uV = max_uV;
+	ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE,
+				   &data);
+	if (ret & NOTIFY_STOP_MASK)
+		return -EINVAL;
+
+	ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV, selector);
+	if (ret >= 0)
+		return ret;
+
+	_notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE,
+			     (void *)data.old_uV);
+
+	return ret;
+}
+
+static int _regulator_call_set_voltage_sel(struct regulator_dev *rdev,
+					   int uV, unsigned selector)
+{
+	struct pre_voltage_change_data data;
+	int ret;
+
+	data.old_uV = regulator_get_voltage_rdev(rdev);
+	data.min_uV = uV;
+	data.max_uV = uV;
+	ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE,
+				   &data);
+	if (ret & NOTIFY_STOP_MASK)
+		return -EINVAL;
+
+	ret = rdev->desc->ops->set_voltage_sel(rdev, selector);
+	if (ret >= 0)
+		return ret;
+
+	_notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE,
+			     (void *)data.old_uV);
+
+	return ret;
+}
+
+static int _regulator_set_voltage_sel_step(struct regulator_dev *rdev,
+					   int uV, int new_selector)
+{
+	const struct regulator_ops *ops = rdev->desc->ops;
+	int diff, old_sel, curr_sel, ret;
+
+	/* Stepping is only needed if the regulator is enabled. */
+	if (!_regulator_is_enabled(rdev))
+		goto final_set;
+
+	if (!ops->get_voltage_sel)
+		return -EINVAL;
+
+	old_sel = ops->get_voltage_sel(rdev);
+	if (old_sel < 0)
+		return old_sel;
+
+	diff = new_selector - old_sel;
+	if (diff == 0)
+		return 0; /* No change needed. */
+
+	if (diff > 0) {
+		/* Stepping up. */
+		for (curr_sel = old_sel + rdev->desc->vsel_step;
+		     curr_sel < new_selector;
+		     curr_sel += rdev->desc->vsel_step) {
+			/*
+			 * Call the callback directly instead of using
+			 * _regulator_call_set_voltage_sel() as we don't
+			 * want to notify anyone yet. Same in the branch
+			 * below.
+			 */
+			ret = ops->set_voltage_sel(rdev, curr_sel);
+			if (ret)
+				goto try_revert;
+		}
+	} else {
+		/* Stepping down. */
+		for (curr_sel = old_sel - rdev->desc->vsel_step;
+		     curr_sel > new_selector;
+		     curr_sel -= rdev->desc->vsel_step) {
+			ret = ops->set_voltage_sel(rdev, curr_sel);
+			if (ret)
+				goto try_revert;
+		}
+	}
+
+final_set:
+	/* The final selector will trigger the notifiers. */
+	return _regulator_call_set_voltage_sel(rdev, uV, new_selector);
+
+try_revert:
+	/*
+	 * At least try to return to the previous voltage if setting a new
+	 * one failed.
+	 */
+	(void)ops->set_voltage_sel(rdev, old_sel);
+	return ret;
+}
+
+static int _regulator_set_voltage_time(struct regulator_dev *rdev,
+				       int old_uV, int new_uV)
+{
+	unsigned int ramp_delay = 0;
+
+	if (rdev->constraints->ramp_delay)
+		ramp_delay = rdev->constraints->ramp_delay;
+	else if (rdev->desc->ramp_delay)
+		ramp_delay = rdev->desc->ramp_delay;
+	else if (rdev->constraints->settling_time)
+		return rdev->constraints->settling_time;
+	else if (rdev->constraints->settling_time_up &&
+		 (new_uV > old_uV))
+		return rdev->constraints->settling_time_up;
+	else if (rdev->constraints->settling_time_down &&
+		 (new_uV < old_uV))
+		return rdev->constraints->settling_time_down;
+
+	if (ramp_delay == 0) {
+		rdev_dbg(rdev, "ramp_delay not set\n");
+		return 0;
+	}
+
+	return DIV_ROUND_UP(abs(new_uV - old_uV), ramp_delay);
+}
+
+static int _regulator_do_set_voltage(struct regulator_dev *rdev,
+				     int min_uV, int max_uV)
+{
+	int ret;
+	int delay = 0;
+	int best_val = 0;
+	unsigned int selector;
+	int old_selector = -1;
+	const struct regulator_ops *ops = rdev->desc->ops;
+	int old_uV = regulator_get_voltage_rdev(rdev);
+
+	trace_regulator_set_voltage(rdev_get_name(rdev), min_uV, max_uV);
+
+	min_uV += rdev->constraints->uV_offset;
+	max_uV += rdev->constraints->uV_offset;
+
+	/*
+	 * If we can't obtain the old selector there is not enough
+	 * info to call set_voltage_time_sel().
+	 */
+	if (_regulator_is_enabled(rdev) &&
+	    ops->set_voltage_time_sel && ops->get_voltage_sel) {
+		old_selector = ops->get_voltage_sel(rdev);
+		if (old_selector < 0)
+			return old_selector;
+	}
+
+	if (ops->set_voltage) {
+		ret = _regulator_call_set_voltage(rdev, min_uV, max_uV,
+						  &selector);
+
+		if (ret >= 0) {
+			if (ops->list_voltage)
+				best_val = ops->list_voltage(rdev,
+							     selector);
+			else
+				best_val = regulator_get_voltage_rdev(rdev);
+		}
+
+	} else if (ops->set_voltage_sel) {
+		ret = regulator_map_voltage(rdev, min_uV, max_uV);
+		if (ret >= 0) {
+			best_val = ops->list_voltage(rdev, ret);
+			if (min_uV <= best_val && max_uV >= best_val) {
+				selector = ret;
+				if (old_selector == selector)
+					ret = 0;
+				else if (rdev->desc->vsel_step)
+					ret = _regulator_set_voltage_sel_step(
+						rdev, best_val, selector);
+				else
+					ret = _regulator_call_set_voltage_sel(
+						rdev, best_val, selector);
+			} else {
+				ret = -EINVAL;
+			}
+		}
+	} else {
+		ret = -EINVAL;
+	}
+
+	if (ret)
+		goto out;
+
+	if (ops->set_voltage_time_sel) {
+		/*
+		 * Call set_voltage_time_sel if successfully obtained
+		 * old_selector
+		 */
+		if (old_selector >= 0 && old_selector != selector)
+			delay = ops->set_voltage_time_sel(rdev, old_selector,
+							  selector);
+	} else {
+		if (old_uV != best_val) {
+			if (ops->set_voltage_time)
+				delay = ops->set_voltage_time(rdev, old_uV,
+							      best_val);
+			else
+				delay = _regulator_set_voltage_time(rdev,
+								    old_uV,
+								    best_val);
+		}
+	}
+
+	if (delay < 0) {
+		rdev_warn(rdev, "failed to get delay: %pe\n", ERR_PTR(delay));
+		delay = 0;
+	}
+
+	/* Insert any necessary delays */
+	if (delay >= 1000) {
+		mdelay(delay / 1000);
+		udelay(delay % 1000);
+	} else if (delay) {
+		udelay(delay);
+	}
+
+	if (best_val >= 0) {
+		unsigned long data = best_val;
+
+		_notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE,
+				     (void *)data);
+	}
+
+out:
+	trace_regulator_set_voltage_complete(rdev_get_name(rdev), best_val);
+
+	return ret;
+}
+
+static int _regulator_do_set_suspend_voltage(struct regulator_dev *rdev,
+				  int min_uV, int max_uV, suspend_state_t state)
+{
+	struct regulator_state *rstate;
+	int uV, sel;
+
+	rstate = regulator_get_suspend_state(rdev, state);
+	if (rstate == NULL)
+		return -EINVAL;
+
+	if (min_uV < rstate->min_uV)
+		min_uV = rstate->min_uV;
+	if (max_uV > rstate->max_uV)
+		max_uV = rstate->max_uV;
+
+	sel = regulator_map_voltage(rdev, min_uV, max_uV);
+	if (sel < 0)
+		return sel;
+
+	uV = rdev->desc->ops->list_voltage(rdev, sel);
+	if (uV >= min_uV && uV <= max_uV)
+		rstate->uV = uV;
+
+	return 0;
+}
+
+static int regulator_set_voltage_unlocked(struct regulator *regulator,
+					  int min_uV, int max_uV,
+					  suspend_state_t state)
+{
+	struct regulator_dev *rdev = regulator->rdev;
+	struct regulator_voltage *voltage = &regulator->voltage[state];
+	int ret = 0;
+	int old_min_uV, old_max_uV;
+	int current_uV;
+
+	/* If we're setting the same range as last time the change
+	 * should be a noop (some cpufreq implementations use the same
+	 * voltage for multiple frequencies, for example).
+	 */
+	if (voltage->min_uV == min_uV && voltage->max_uV == max_uV)
+		goto out;
+
+	/* If we're trying to set a range that overlaps the current voltage,
+	 * return successfully even though the regulator does not support
+	 * changing the voltage.
+	 */
+	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE)) {
+		current_uV = regulator_get_voltage_rdev(rdev);
+		if (min_uV <= current_uV && current_uV <= max_uV) {
+			voltage->min_uV = min_uV;
+			voltage->max_uV = max_uV;
+			goto out;
+		}
+	}
+
+	/* sanity check */
+	if (!rdev->desc->ops->set_voltage &&
+	    !rdev->desc->ops->set_voltage_sel) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	/* constraints check */
+	ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
+	if (ret < 0)
+		goto out;
+
+	/* restore original values in case of error */
+	old_min_uV = voltage->min_uV;
+	old_max_uV = voltage->max_uV;
+	voltage->min_uV = min_uV;
+	voltage->max_uV = max_uV;
+
+	/* for not coupled regulators this will just set the voltage */
+	ret = regulator_balance_voltage(rdev, state);
+	if (ret < 0) {
+		voltage->min_uV = old_min_uV;
+		voltage->max_uV = old_max_uV;
+	}
+
+out:
+	return ret;
+}
+
+int regulator_set_voltage_rdev(struct regulator_dev *rdev, int min_uV,
+			       int max_uV, suspend_state_t state)
+{
+	int best_supply_uV = 0;
+	int supply_change_uV = 0;
+	int ret;
+
+	if (rdev->supply &&
+	    regulator_ops_is_valid(rdev->supply->rdev,
+				   REGULATOR_CHANGE_VOLTAGE) &&
+	    (rdev->desc->min_dropout_uV || !(rdev->desc->ops->get_voltage ||
+					   rdev->desc->ops->get_voltage_sel))) {
+		int current_supply_uV;
+		int selector;
+
+		selector = regulator_map_voltage(rdev, min_uV, max_uV);
+		if (selector < 0) {
+			ret = selector;
+			goto out;
+		}
+
+		best_supply_uV = _regulator_list_voltage(rdev, selector, 0);
+		if (best_supply_uV < 0) {
+			ret = best_supply_uV;
+			goto out;
+		}
+
+		best_supply_uV += rdev->desc->min_dropout_uV;
+
+		current_supply_uV = regulator_get_voltage_rdev(rdev->supply->rdev);
+		if (current_supply_uV < 0) {
+			ret = current_supply_uV;
+			goto out;
+		}
+
+		supply_change_uV = best_supply_uV - current_supply_uV;
+	}
+
+	if (supply_change_uV > 0) {
+		ret = regulator_set_voltage_unlocked(rdev->supply,
+				best_supply_uV, INT_MAX, state);
+		if (ret) {
+			dev_err(&rdev->dev, "Failed to increase supply voltage: %pe\n",
+				ERR_PTR(ret));
+			goto out;
+		}
+	}
+
+	if (state == PM_SUSPEND_ON)
+		ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
+	else
+		ret = _regulator_do_set_suspend_voltage(rdev, min_uV,
+							max_uV, state);
+	if (ret < 0)
+		goto out;
+
+	if (supply_change_uV < 0) {
+		ret = regulator_set_voltage_unlocked(rdev->supply,
+				best_supply_uV, INT_MAX, state);
+		if (ret)
+			dev_warn(&rdev->dev, "Failed to decrease supply voltage: %pe\n",
+				 ERR_PTR(ret));
+		/* No need to fail here */
+		ret = 0;
+	}
+
+out:
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_set_voltage_rdev);
+
+static int regulator_limit_voltage_step(struct regulator_dev *rdev,
+					int *current_uV, int *min_uV)
+{
+	struct regulation_constraints *constraints = rdev->constraints;
+
+	/* Limit voltage change only if necessary */
+	if (!constraints->max_uV_step || !_regulator_is_enabled(rdev))
+		return 1;
+
+	if (*current_uV < 0) {
+		*current_uV = regulator_get_voltage_rdev(rdev);
+
+		if (*current_uV < 0)
+			return *current_uV;
+	}
+
+	if (abs(*current_uV - *min_uV) <= constraints->max_uV_step)
+		return 1;
+
+	/* Clamp target voltage within the given step */
+	if (*current_uV < *min_uV)
+		*min_uV = min(*current_uV + constraints->max_uV_step,
+			      *min_uV);
+	else
+		*min_uV = max(*current_uV - constraints->max_uV_step,
+			      *min_uV);
+
+	return 0;
+}
+
+static int regulator_get_optimal_voltage(struct regulator_dev *rdev,
+					 int *current_uV,
+					 int *min_uV, int *max_uV,
+					 suspend_state_t state,
+					 int n_coupled)
+{
+	struct coupling_desc *c_desc = &rdev->coupling_desc;
+	struct regulator_dev **c_rdevs = c_desc->coupled_rdevs;
+	struct regulation_constraints *constraints = rdev->constraints;
+	int desired_min_uV = 0, desired_max_uV = INT_MAX;
+	int max_current_uV = 0, min_current_uV = INT_MAX;
+	int highest_min_uV = 0, target_uV, possible_uV;
+	int i, ret, max_spread;
+	bool done;
+
+	*current_uV = -1;
+
+	/*
+	 * If there are no coupled regulators, simply set the voltage
+	 * demanded by consumers.
+	 */
+	if (n_coupled == 1) {
+		/*
+		 * If consumers don't provide any demands, set voltage
+		 * to min_uV
+		 */
+		desired_min_uV = constraints->min_uV;
+		desired_max_uV = constraints->max_uV;
+
+		ret = regulator_check_consumers(rdev,
+						&desired_min_uV,
+						&desired_max_uV, state);
+		if (ret < 0)
+			return ret;
+
+		possible_uV = desired_min_uV;
+		done = true;
+
+		goto finish;
+	}
+
+	/* Find highest min desired voltage */
+	for (i = 0; i < n_coupled; i++) {
+		int tmp_min = 0;
+		int tmp_max = INT_MAX;
+
+		lockdep_assert_held_once(&c_rdevs[i]->mutex.base);
+
+		ret = regulator_check_consumers(c_rdevs[i],
+						&tmp_min,
+						&tmp_max, state);
+		if (ret < 0)
+			return ret;
+
+		ret = regulator_check_voltage(c_rdevs[i], &tmp_min, &tmp_max);
+		if (ret < 0)
+			return ret;
+
+		highest_min_uV = max(highest_min_uV, tmp_min);
+
+		if (i == 0) {
+			desired_min_uV = tmp_min;
+			desired_max_uV = tmp_max;
+		}
+	}
+
+	max_spread = constraints->max_spread[0];
+
+	/*
+	 * Let target_uV be equal to the desired one if possible.
+	 * If not, set it to minimum voltage, allowed by other coupled
+	 * regulators.
+	 */
+	target_uV = max(desired_min_uV, highest_min_uV - max_spread);
+
+	/*
+	 * Find min and max voltages, which currently aren't violating
+	 * max_spread.
+	 */
+	for (i = 1; i < n_coupled; i++) {
+		int tmp_act;
+
+		if (!_regulator_is_enabled(c_rdevs[i]))
+			continue;
+
+		tmp_act = regulator_get_voltage_rdev(c_rdevs[i]);
+		if (tmp_act < 0)
+			return tmp_act;
+
+		min_current_uV = min(tmp_act, min_current_uV);
+		max_current_uV = max(tmp_act, max_current_uV);
+	}
+
+	/* There aren't any other regulators enabled */
+	if (max_current_uV == 0) {
+		possible_uV = target_uV;
+	} else {
+		/*
+		 * Correct target voltage, so as it currently isn't
+		 * violating max_spread
+		 */
+		possible_uV = max(target_uV, max_current_uV - max_spread);
+		possible_uV = min(possible_uV, min_current_uV + max_spread);
+	}
+
+	if (possible_uV > desired_max_uV)
+		return -EINVAL;
+
+	done = (possible_uV == target_uV);
+	desired_min_uV = possible_uV;
+
+finish:
+	/* Apply max_uV_step constraint if necessary */
+	if (state == PM_SUSPEND_ON) {
+		ret = regulator_limit_voltage_step(rdev, current_uV,
+						   &desired_min_uV);
+		if (ret < 0)
+			return ret;
+
+		if (ret == 0)
+			done = false;
+	}
+
+	/* Set current_uV if wasn't done earlier in the code and if necessary */
+	if (n_coupled > 1 && *current_uV == -1) {
+
+		if (_regulator_is_enabled(rdev)) {
+			ret = regulator_get_voltage_rdev(rdev);
+			if (ret < 0)
+				return ret;
+
+			*current_uV = ret;
+		} else {
+			*current_uV = desired_min_uV;
+		}
+	}
+
+	*min_uV = desired_min_uV;
+	*max_uV = desired_max_uV;
+
+	return done;
+}
+
+int regulator_do_balance_voltage(struct regulator_dev *rdev,
+				 suspend_state_t state, bool skip_coupled)
+{
+	struct regulator_dev **c_rdevs;
+	struct regulator_dev *best_rdev;
+	struct coupling_desc *c_desc = &rdev->coupling_desc;
+	int i, ret, n_coupled, best_min_uV, best_max_uV, best_c_rdev;
+	unsigned int delta, best_delta;
+	unsigned long c_rdev_done = 0;
+	bool best_c_rdev_done;
+
+	c_rdevs = c_desc->coupled_rdevs;
+	n_coupled = skip_coupled ? 1 : c_desc->n_coupled;
+
+	/*
+	 * Find the best possible voltage change on each loop. Leave the loop
+	 * if there isn't any possible change.
+	 */
+	do {
+		best_c_rdev_done = false;
+		best_delta = 0;
+		best_min_uV = 0;
+		best_max_uV = 0;
+		best_c_rdev = 0;
+		best_rdev = NULL;
+
+		/*
+		 * Find highest difference between optimal voltage
+		 * and current voltage.
+		 */
+		for (i = 0; i < n_coupled; i++) {
+			/*
+			 * optimal_uV is the best voltage that can be set for
+			 * i-th regulator at the moment without violating
+			 * max_spread constraint in order to balance
+			 * the coupled voltages.
+			 */
+			int optimal_uV = 0, optimal_max_uV = 0, current_uV = 0;
+
+			if (test_bit(i, &c_rdev_done))
+				continue;
+
+			ret = regulator_get_optimal_voltage(c_rdevs[i],
+							    &current_uV,
+							    &optimal_uV,
+							    &optimal_max_uV,
+							    state, n_coupled);
+			if (ret < 0)
+				goto out;
+
+			delta = abs(optimal_uV - current_uV);
+
+			if (delta && best_delta <= delta) {
+				best_c_rdev_done = ret;
+				best_delta = delta;
+				best_rdev = c_rdevs[i];
+				best_min_uV = optimal_uV;
+				best_max_uV = optimal_max_uV;
+				best_c_rdev = i;
+			}
+		}
+
+		/* Nothing to change, return successfully */
+		if (!best_rdev) {
+			ret = 0;
+			goto out;
+		}
+
+		ret = regulator_set_voltage_rdev(best_rdev, best_min_uV,
+						 best_max_uV, state);
+
+		if (ret < 0)
+			goto out;
+
+		if (best_c_rdev_done)
+			set_bit(best_c_rdev, &c_rdev_done);
+
+	} while (n_coupled > 1);
+
+out:
+	return ret;
+}
+
+static int regulator_balance_voltage(struct regulator_dev *rdev,
+				     suspend_state_t state)
+{
+	struct coupling_desc *c_desc = &rdev->coupling_desc;
+	struct regulator_coupler *coupler = c_desc->coupler;
+	bool skip_coupled = false;
+
+	/*
+	 * If system is in a state other than PM_SUSPEND_ON, don't check
+	 * other coupled regulators.
+	 */
+	if (state != PM_SUSPEND_ON)
+		skip_coupled = true;
+
+	if (c_desc->n_resolved < c_desc->n_coupled) {
+		rdev_err(rdev, "Not all coupled regulators registered\n");
+		return -EPERM;
+	}
+
+	/* Invoke custom balancer for customized couplers */
+	if (coupler && coupler->balance_voltage)
+		return coupler->balance_voltage(coupler, rdev, state);
+
+	return regulator_do_balance_voltage(rdev, state, skip_coupled);
+}
+
+/**
+ * regulator_set_voltage - set regulator output voltage
+ * @regulator: regulator source
+ * @min_uV: Minimum required voltage in uV
+ * @max_uV: Maximum acceptable voltage in uV
+ *
+ * Sets a voltage regulator to the desired output voltage. This can be set
+ * during any regulator state. IOW, regulator can be disabled or enabled.
+ *
+ * If the regulator is enabled then the voltage will change to the new value
+ * immediately otherwise if the regulator is disabled the regulator will
+ * output at the new voltage when enabled.
+ *
+ * NOTE: If the regulator is shared between several devices then the lowest
+ * request voltage that meets the system constraints will be used.
+ * Regulator system constraints must be set for this regulator before
+ * calling this function otherwise this call will fail.
+ */
+int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
+{
+	struct ww_acquire_ctx ww_ctx;
+	int ret;
+
+	regulator_lock_dependent(regulator->rdev, &ww_ctx);
+
+	ret = regulator_set_voltage_unlocked(regulator, min_uV, max_uV,
+					     PM_SUSPEND_ON);
+
+	regulator_unlock_dependent(regulator->rdev, &ww_ctx);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_set_voltage);
+
+static inline int regulator_suspend_toggle(struct regulator_dev *rdev,
+					   suspend_state_t state, bool en)
+{
+	struct regulator_state *rstate;
+
+	rstate = regulator_get_suspend_state(rdev, state);
+	if (rstate == NULL)
+		return -EINVAL;
+
+	if (!rstate->changeable)
+		return -EPERM;
+
+	rstate->enabled = (en) ? ENABLE_IN_SUSPEND : DISABLE_IN_SUSPEND;
+
+	return 0;
+}
+
+int regulator_suspend_enable(struct regulator_dev *rdev,
+				    suspend_state_t state)
+{
+	return regulator_suspend_toggle(rdev, state, true);
+}
+EXPORT_SYMBOL_GPL(regulator_suspend_enable);
+
+int regulator_suspend_disable(struct regulator_dev *rdev,
+				     suspend_state_t state)
+{
+	struct regulator *regulator;
+	struct regulator_voltage *voltage;
+
+	/*
+	 * if any consumer wants this regulator device keeping on in
+	 * suspend states, don't set it as disabled.
+	 */
+	list_for_each_entry(regulator, &rdev->consumer_list, list) {
+		voltage = &regulator->voltage[state];
+		if (voltage->min_uV || voltage->max_uV)
+			return 0;
+	}
+
+	return regulator_suspend_toggle(rdev, state, false);
+}
+EXPORT_SYMBOL_GPL(regulator_suspend_disable);
+
+static int _regulator_set_suspend_voltage(struct regulator *regulator,
+					  int min_uV, int max_uV,
+					  suspend_state_t state)
+{
+	struct regulator_dev *rdev = regulator->rdev;
+	struct regulator_state *rstate;
+
+	rstate = regulator_get_suspend_state(rdev, state);
+	if (rstate == NULL)
+		return -EINVAL;
+
+	if (rstate->min_uV == rstate->max_uV) {
+		rdev_err(rdev, "The suspend voltage can't be changed!\n");
+		return -EPERM;
+	}
+
+	return regulator_set_voltage_unlocked(regulator, min_uV, max_uV, state);
+}
+
+int regulator_set_suspend_voltage(struct regulator *regulator, int min_uV,
+				  int max_uV, suspend_state_t state)
+{
+	struct ww_acquire_ctx ww_ctx;
+	int ret;
+
+	/* PM_SUSPEND_ON is handled by regulator_set_voltage() */
+	if (regulator_check_states(state) || state == PM_SUSPEND_ON)
+		return -EINVAL;
+
+	regulator_lock_dependent(regulator->rdev, &ww_ctx);
+
+	ret = _regulator_set_suspend_voltage(regulator, min_uV,
+					     max_uV, state);
+
+	regulator_unlock_dependent(regulator->rdev, &ww_ctx);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_set_suspend_voltage);
+
+/**
+ * regulator_set_voltage_time - get raise/fall time
+ * @regulator: regulator source
+ * @old_uV: starting voltage in microvolts
+ * @new_uV: target voltage in microvolts
+ *
+ * Provided with the starting and ending voltage, this function attempts to
+ * calculate the time in microseconds required to rise or fall to this new
+ * voltage.
+ */
+int regulator_set_voltage_time(struct regulator *regulator,
+			       int old_uV, int new_uV)
+{
+	struct regulator_dev *rdev = regulator->rdev;
+	const struct regulator_ops *ops = rdev->desc->ops;
+	int old_sel = -1;
+	int new_sel = -1;
+	int voltage;
+	int i;
+
+	if (ops->set_voltage_time)
+		return ops->set_voltage_time(rdev, old_uV, new_uV);
+	else if (!ops->set_voltage_time_sel)
+		return _regulator_set_voltage_time(rdev, old_uV, new_uV);
+
+	/* Currently requires operations to do this */
+	if (!ops->list_voltage || !rdev->desc->n_voltages)
+		return -EINVAL;
+
+	for (i = 0; i < rdev->desc->n_voltages; i++) {
+		/* We only look for exact voltage matches here */
+		voltage = regulator_list_voltage(regulator, i);
+		if (voltage < 0)
+			return -EINVAL;
+		if (voltage == 0)
+			continue;
+		if (voltage == old_uV)
+			old_sel = i;
+		if (voltage == new_uV)
+			new_sel = i;
+	}
+
+	if (old_sel < 0 || new_sel < 0)
+		return -EINVAL;
+
+	return ops->set_voltage_time_sel(rdev, old_sel, new_sel);
+}
+EXPORT_SYMBOL_GPL(regulator_set_voltage_time);
+
+/**
+ * regulator_set_voltage_time_sel - get raise/fall time
+ * @rdev: regulator source device
+ * @old_selector: selector for starting voltage
+ * @new_selector: selector for target voltage
+ *
+ * Provided with the starting and target voltage selectors, this function
+ * returns time in microseconds required to rise or fall to this new voltage
+ *
+ * Drivers providing ramp_delay in regulation_constraints can use this as their
+ * set_voltage_time_sel() operation.
+ */
+int regulator_set_voltage_time_sel(struct regulator_dev *rdev,
+				   unsigned int old_selector,
+				   unsigned int new_selector)
+{
+	int old_volt, new_volt;
+
+	/* sanity check */
+	if (!rdev->desc->ops->list_voltage)
+		return -EINVAL;
+
+	old_volt = rdev->desc->ops->list_voltage(rdev, old_selector);
+	new_volt = rdev->desc->ops->list_voltage(rdev, new_selector);
+
+	if (rdev->desc->ops->set_voltage_time)
+		return rdev->desc->ops->set_voltage_time(rdev, old_volt,
+							 new_volt);
+	else
+		return _regulator_set_voltage_time(rdev, old_volt, new_volt);
+}
+EXPORT_SYMBOL_GPL(regulator_set_voltage_time_sel);
+
+/**
+ * regulator_sync_voltage - re-apply last regulator output voltage
+ * @regulator: regulator source
+ *
+ * Re-apply the last configured voltage.  This is intended to be used
+ * where some external control source the consumer is cooperating with
+ * has caused the configured voltage to change.
+ */
+int regulator_sync_voltage(struct regulator *regulator)
+{
+	struct regulator_dev *rdev = regulator->rdev;
+	struct regulator_voltage *voltage = &regulator->voltage[PM_SUSPEND_ON];
+	int ret, min_uV, max_uV;
+
+	regulator_lock(rdev);
+
+	if (!rdev->desc->ops->set_voltage &&
+	    !rdev->desc->ops->set_voltage_sel) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	/* This is only going to work if we've had a voltage configured. */
+	if (!voltage->min_uV && !voltage->max_uV) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	min_uV = voltage->min_uV;
+	max_uV = voltage->max_uV;
+
+	/* This should be a paranoia check... */
+	ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
+	if (ret < 0)
+		goto out;
+
+	ret = regulator_check_consumers(rdev, &min_uV, &max_uV, 0);
+	if (ret < 0)
+		goto out;
+
+	ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
+
+out:
+	regulator_unlock(rdev);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_sync_voltage);
+
+int regulator_get_voltage_rdev(struct regulator_dev *rdev)
+{
+	int sel, ret;
+	bool bypassed;
+
+	if (rdev->desc->ops->get_bypass) {
+		ret = rdev->desc->ops->get_bypass(rdev, &bypassed);
+		if (ret < 0)
+			return ret;
+		if (bypassed) {
+			/* if bypassed the regulator must have a supply */
+			if (!rdev->supply) {
+				rdev_err(rdev,
+					 "bypassed regulator has no supply!\n");
+				return -EPROBE_DEFER;
+			}
+
+			return regulator_get_voltage_rdev(rdev->supply->rdev);
+		}
+	}
+
+	if (rdev->desc->ops->get_voltage_sel) {
+		sel = rdev->desc->ops->get_voltage_sel(rdev);
+		if (sel < 0)
+			return sel;
+		ret = rdev->desc->ops->list_voltage(rdev, sel);
+	} else if (rdev->desc->ops->get_voltage) {
+		ret = rdev->desc->ops->get_voltage(rdev);
+	} else if (rdev->desc->ops->list_voltage) {
+		ret = rdev->desc->ops->list_voltage(rdev, 0);
+	} else if (rdev->desc->fixed_uV && (rdev->desc->n_voltages == 1)) {
+		ret = rdev->desc->fixed_uV;
+	} else if (rdev->supply) {
+		ret = regulator_get_voltage_rdev(rdev->supply->rdev);
+	} else if (rdev->supply_name) {
+		return -EPROBE_DEFER;
+	} else {
+		return -EINVAL;
+	}
+
+	if (ret < 0)
+		return ret;
+	return ret - rdev->constraints->uV_offset;
+}
+EXPORT_SYMBOL_GPL(regulator_get_voltage_rdev);
+
+/**
+ * regulator_get_voltage - get regulator output voltage
+ * @regulator: regulator source
+ *
+ * This returns the current regulator voltage in uV.
+ *
+ * NOTE: If the regulator is disabled it will return the voltage value. This
+ * function should not be used to determine regulator state.
+ */
+int regulator_get_voltage(struct regulator *regulator)
+{
+	struct ww_acquire_ctx ww_ctx;
+	int ret;
+
+	regulator_lock_dependent(regulator->rdev, &ww_ctx);
+	ret = regulator_get_voltage_rdev(regulator->rdev);
+	regulator_unlock_dependent(regulator->rdev, &ww_ctx);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_get_voltage);
+
+/**
+ * regulator_set_current_limit - set regulator output current limit
+ * @regulator: regulator source
+ * @min_uA: Minimum supported current in uA
+ * @max_uA: Maximum supported current in uA
+ *
+ * Sets current sink to the desired output current. This can be set during
+ * any regulator state. IOW, regulator can be disabled or enabled.
+ *
+ * If the regulator is enabled then the current will change to the new value
+ * immediately otherwise if the regulator is disabled the regulator will
+ * output at the new current when enabled.
+ *
+ * NOTE: Regulator system constraints must be set for this regulator before
+ * calling this function otherwise this call will fail.
+ */
+int regulator_set_current_limit(struct regulator *regulator,
+			       int min_uA, int max_uA)
+{
+	struct regulator_dev *rdev = regulator->rdev;
+	int ret;
+
+	regulator_lock(rdev);
+
+	/* sanity check */
+	if (!rdev->desc->ops->set_current_limit) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	/* constraints check */
+	ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
+	if (ret < 0)
+		goto out;
+
+	ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
+out:
+	regulator_unlock(rdev);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_set_current_limit);
+
+static int _regulator_get_current_limit_unlocked(struct regulator_dev *rdev)
+{
+	/* sanity check */
+	if (!rdev->desc->ops->get_current_limit)
+		return -EINVAL;
+
+	return rdev->desc->ops->get_current_limit(rdev);
+}
+
+static int _regulator_get_current_limit(struct regulator_dev *rdev)
+{
+	int ret;
+
+	regulator_lock(rdev);
+	ret = _regulator_get_current_limit_unlocked(rdev);
+	regulator_unlock(rdev);
+
+	return ret;
+}
+
+/**
+ * regulator_get_current_limit - get regulator output current
+ * @regulator: regulator source
+ *
+ * This returns the current supplied by the specified current sink in uA.
+ *
+ * NOTE: If the regulator is disabled it will return the current value. This
+ * function should not be used to determine regulator state.
+ */
+int regulator_get_current_limit(struct regulator *regulator)
+{
+	return _regulator_get_current_limit(regulator->rdev);
+}
+EXPORT_SYMBOL_GPL(regulator_get_current_limit);
+
+/**
+ * regulator_set_mode - set regulator operating mode
+ * @regulator: regulator source
+ * @mode: operating mode - one of the REGULATOR_MODE constants
+ *
+ * Set regulator operating mode to increase regulator efficiency or improve
+ * regulation performance.
+ *
+ * NOTE: Regulator system constraints must be set for this regulator before
+ * calling this function otherwise this call will fail.
+ */
+int regulator_set_mode(struct regulator *regulator, unsigned int mode)
+{
+	struct regulator_dev *rdev = regulator->rdev;
+	int ret;
+	int regulator_curr_mode;
+
+	regulator_lock(rdev);
+
+	/* sanity check */
+	if (!rdev->desc->ops->set_mode) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	/* return if the same mode is requested */
+	if (rdev->desc->ops->get_mode) {
+		regulator_curr_mode = rdev->desc->ops->get_mode(rdev);
+		if (regulator_curr_mode == mode) {
+			ret = 0;
+			goto out;
+		}
+	}
+
+	/* constraints check */
+	ret = regulator_mode_constrain(rdev, &mode);
+	if (ret < 0)
+		goto out;
+
+	ret = rdev->desc->ops->set_mode(rdev, mode);
+out:
+	regulator_unlock(rdev);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_set_mode);
+
+static unsigned int _regulator_get_mode_unlocked(struct regulator_dev *rdev)
+{
+	/* sanity check */
+	if (!rdev->desc->ops->get_mode)
+		return -EINVAL;
+
+	return rdev->desc->ops->get_mode(rdev);
+}
+
+static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
+{
+	int ret;
+
+	regulator_lock(rdev);
+	ret = _regulator_get_mode_unlocked(rdev);
+	regulator_unlock(rdev);
+
+	return ret;
+}
+
+/**
+ * regulator_get_mode - get regulator operating mode
+ * @regulator: regulator source
+ *
+ * Get the current regulator operating mode.
+ */
+unsigned int regulator_get_mode(struct regulator *regulator)
+{
+	return _regulator_get_mode(regulator->rdev);
+}
+EXPORT_SYMBOL_GPL(regulator_get_mode);
+
+static int _regulator_get_error_flags(struct regulator_dev *rdev,
+					unsigned int *flags)
+{
+	int ret;
+
+	regulator_lock(rdev);
+
+	/* sanity check */
+	if (!rdev->desc->ops->get_error_flags) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	ret = rdev->desc->ops->get_error_flags(rdev, flags);
+out:
+	regulator_unlock(rdev);
+	return ret;
+}
+
+/**
+ * regulator_get_error_flags - get regulator error information
+ * @regulator: regulator source
+ * @flags: pointer to store error flags
+ *
+ * Get the current regulator error information.
+ */
+int regulator_get_error_flags(struct regulator *regulator,
+				unsigned int *flags)
+{
+	return _regulator_get_error_flags(regulator->rdev, flags);
+}
+EXPORT_SYMBOL_GPL(regulator_get_error_flags);
+
+/**
+ * regulator_set_load - set regulator load
+ * @regulator: regulator source
+ * @uA_load: load current
+ *
+ * Notifies the regulator core of a new device load. This is then used by
+ * DRMS (if enabled by constraints) to set the most efficient regulator
+ * operating mode for the new regulator loading.
+ *
+ * Consumer devices notify their supply regulator of the maximum power
+ * they will require (can be taken from device datasheet in the power
+ * consumption tables) when they change operational status and hence power
+ * state. Examples of operational state changes that can affect power
+ * consumption are :-
+ *
+ *    o Device is opened / closed.
+ *    o Device I/O is about to begin or has just finished.
+ *    o Device is idling in between work.
+ *
+ * This information is also exported via sysfs to userspace.
+ *
+ * DRMS will sum the total requested load on the regulator and change
+ * to the most efficient operating mode if platform constraints allow.
+ *
+ * NOTE: when a regulator consumer requests to have a regulator
+ * disabled then any load that consumer requested no longer counts
+ * toward the total requested load.  If the regulator is re-enabled
+ * then the previously requested load will start counting again.
+ *
+ * If a regulator is an always-on regulator then an individual consumer's
+ * load will still be removed if that consumer is fully disabled.
+ *
+ * On error a negative errno is returned.
+ */
+int regulator_set_load(struct regulator *regulator, int uA_load)
+{
+	struct regulator_dev *rdev = regulator->rdev;
+	int old_uA_load;
+	int ret = 0;
+
+	regulator_lock(rdev);
+	old_uA_load = regulator->uA_load;
+	regulator->uA_load = uA_load;
+	if (regulator->enable_count && old_uA_load != uA_load) {
+		ret = drms_uA_update(rdev);
+		if (ret < 0)
+			regulator->uA_load = old_uA_load;
+	}
+	regulator_unlock(rdev);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_set_load);
+
+/**
+ * regulator_allow_bypass - allow the regulator to go into bypass mode
+ *
+ * @regulator: Regulator to configure
+ * @enable: enable or disable bypass mode
+ *
+ * Allow the regulator to go into bypass mode if all other consumers
+ * for the regulator also enable bypass mode and the machine
+ * constraints allow this.  Bypass mode means that the regulator is
+ * simply passing the input directly to the output with no regulation.
+ */
+int regulator_allow_bypass(struct regulator *regulator, bool enable)
+{
+	struct regulator_dev *rdev = regulator->rdev;
+	const char *name = rdev_get_name(rdev);
+	int ret = 0;
+
+	if (!rdev->desc->ops->set_bypass)
+		return 0;
+
+	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_BYPASS))
+		return 0;
+
+	regulator_lock(rdev);
+
+	if (enable && !regulator->bypass) {
+		rdev->bypass_count++;
+
+		if (rdev->bypass_count == rdev->open_count) {
+			trace_regulator_bypass_enable(name);
+
+			ret = rdev->desc->ops->set_bypass(rdev, enable);
+			if (ret != 0)
+				rdev->bypass_count--;
+			else
+				trace_regulator_bypass_enable_complete(name);
+		}
+
+	} else if (!enable && regulator->bypass) {
+		rdev->bypass_count--;
+
+		if (rdev->bypass_count != rdev->open_count) {
+			trace_regulator_bypass_disable(name);
+
+			ret = rdev->desc->ops->set_bypass(rdev, enable);
+			if (ret != 0)
+				rdev->bypass_count++;
+			else
+				trace_regulator_bypass_disable_complete(name);
+		}
+	}
+
+	if (ret == 0)
+		regulator->bypass = enable;
+
+	regulator_unlock(rdev);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_allow_bypass);
+
+/**
+ * regulator_register_notifier - register regulator event notifier
+ * @regulator: regulator source
+ * @nb: notifier block
+ *
+ * Register notifier block to receive regulator events.
+ */
+int regulator_register_notifier(struct regulator *regulator,
+			      struct notifier_block *nb)
+{
+	return blocking_notifier_chain_register(&regulator->rdev->notifier,
+						nb);
+}
+EXPORT_SYMBOL_GPL(regulator_register_notifier);
+
+/**
+ * regulator_unregister_notifier - unregister regulator event notifier
+ * @regulator: regulator source
+ * @nb: notifier block
+ *
+ * Unregister regulator event notifier block.
+ */
+int regulator_unregister_notifier(struct regulator *regulator,
+				struct notifier_block *nb)
+{
+	return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
+						  nb);
+}
+EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
+
+/* notify regulator consumers and downstream regulator consumers.
+ * Note mutex must be held by caller.
+ */
+static int _notifier_call_chain(struct regulator_dev *rdev,
+				  unsigned long event, void *data)
+{
+	/* call rdev chain first */
+	return blocking_notifier_call_chain(&rdev->notifier, event, data);
+}
+
+/**
+ * regulator_bulk_get - get multiple regulator consumers
+ *
+ * @dev:           Device to supply
+ * @num_consumers: Number of consumers to register
+ * @consumers:     Configuration of consumers; clients are stored here.
+ *
+ * @return 0 on success, an errno on failure.
+ *
+ * This helper function allows drivers to get several regulator
+ * consumers in one operation.  If any of the regulators cannot be
+ * acquired then any regulators that were allocated will be freed
+ * before returning to the caller.
+ */
+int regulator_bulk_get(struct device *dev, int num_consumers,
+		       struct regulator_bulk_data *consumers)
+{
+	int i;
+	int ret;
+
+	for (i = 0; i < num_consumers; i++)
+		consumers[i].consumer = NULL;
+
+	for (i = 0; i < num_consumers; i++) {
+		consumers[i].consumer = regulator_get(dev,
+						      consumers[i].supply);
+		if (IS_ERR(consumers[i].consumer)) {
+			ret = PTR_ERR(consumers[i].consumer);
+			consumers[i].consumer = NULL;
+			goto err;
+		}
+	}
+
+	return 0;
+
+err:
+	if (ret != -EPROBE_DEFER)
+		dev_err(dev, "Failed to get supply '%s': %pe\n",
+			consumers[i].supply, ERR_PTR(ret));
+	else
+		dev_dbg(dev, "Failed to get supply '%s', deferring\n",
+			consumers[i].supply);
+
+	while (--i >= 0)
+		regulator_put(consumers[i].consumer);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_bulk_get);
+
+static void regulator_bulk_enable_async(void *data, async_cookie_t cookie)
+{
+	struct regulator_bulk_data *bulk = data;
+
+	bulk->ret = regulator_enable(bulk->consumer);
+}
+
+/**
+ * regulator_bulk_enable - enable multiple regulator consumers
+ *
+ * @num_consumers: Number of consumers
+ * @consumers:     Consumer data; clients are stored here.
+ * @return         0 on success, an errno on failure
+ *
+ * This convenience API allows consumers to enable multiple regulator
+ * clients in a single API call.  If any consumers cannot be enabled
+ * then any others that were enabled will be disabled again prior to
+ * return.
+ */
+int regulator_bulk_enable(int num_consumers,
+			  struct regulator_bulk_data *consumers)
+{
+	ASYNC_DOMAIN_EXCLUSIVE(async_domain);
+	int i;
+	int ret = 0;
+
+	for (i = 0; i < num_consumers; i++) {
+		async_schedule_domain(regulator_bulk_enable_async,
+				      &consumers[i], &async_domain);
+	}
+
+	async_synchronize_full_domain(&async_domain);
+
+	/* If any consumer failed we need to unwind any that succeeded */
+	for (i = 0; i < num_consumers; i++) {
+		if (consumers[i].ret != 0) {
+			ret = consumers[i].ret;
+			goto err;
+		}
+	}
+
+	return 0;
+
+err:
+	for (i = 0; i < num_consumers; i++) {
+		if (consumers[i].ret < 0)
+			pr_err("Failed to enable %s: %pe\n", consumers[i].supply,
+			       ERR_PTR(consumers[i].ret));
+		else
+			regulator_disable(consumers[i].consumer);
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_bulk_enable);
+
+/**
+ * regulator_bulk_disable - disable multiple regulator consumers
+ *
+ * @num_consumers: Number of consumers
+ * @consumers:     Consumer data; clients are stored here.
+ * @return         0 on success, an errno on failure
+ *
+ * This convenience API allows consumers to disable multiple regulator
+ * clients in a single API call.  If any consumers cannot be disabled
+ * then any others that were disabled will be enabled again prior to
+ * return.
+ */
+int regulator_bulk_disable(int num_consumers,
+			   struct regulator_bulk_data *consumers)
+{
+	int i;
+	int ret, r;
+
+	for (i = num_consumers - 1; i >= 0; --i) {
+		ret = regulator_disable(consumers[i].consumer);
+		if (ret != 0)
+			goto err;
+	}
+
+	return 0;
+
+err:
+	pr_err("Failed to disable %s: %pe\n", consumers[i].supply, ERR_PTR(ret));
+	for (++i; i < num_consumers; ++i) {
+		r = regulator_enable(consumers[i].consumer);
+		if (r != 0)
+			pr_err("Failed to re-enable %s: %pe\n",
+			       consumers[i].supply, ERR_PTR(r));
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_bulk_disable);
+
+/**
+ * regulator_bulk_force_disable - force disable multiple regulator consumers
+ *
+ * @num_consumers: Number of consumers
+ * @consumers:     Consumer data; clients are stored here.
+ * @return         0 on success, an errno on failure
+ *
+ * This convenience API allows consumers to forcibly disable multiple regulator
+ * clients in a single API call.
+ * NOTE: This should be used for situations when device damage will
+ * likely occur if the regulators are not disabled (e.g. over temp).
+ * Although regulator_force_disable function call for some consumers can
+ * return error numbers, the function is called for all consumers.
+ */
+int regulator_bulk_force_disable(int num_consumers,
+			   struct regulator_bulk_data *consumers)
+{
+	int i;
+	int ret = 0;
+
+	for (i = 0; i < num_consumers; i++) {
+		consumers[i].ret =
+			    regulator_force_disable(consumers[i].consumer);
+
+		/* Store first error for reporting */
+		if (consumers[i].ret && !ret)
+			ret = consumers[i].ret;
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_bulk_force_disable);
+
+/**
+ * regulator_bulk_free - free multiple regulator consumers
+ *
+ * @num_consumers: Number of consumers
+ * @consumers:     Consumer data; clients are stored here.
+ *
+ * This convenience API allows consumers to free multiple regulator
+ * clients in a single API call.
+ */
+void regulator_bulk_free(int num_consumers,
+			 struct regulator_bulk_data *consumers)
+{
+	int i;
+
+	for (i = 0; i < num_consumers; i++) {
+		regulator_put(consumers[i].consumer);
+		consumers[i].consumer = NULL;
+	}
+}
+EXPORT_SYMBOL_GPL(regulator_bulk_free);
+
+/**
+ * regulator_notifier_call_chain - call regulator event notifier
+ * @rdev: regulator source
+ * @event: notifier block
+ * @data: callback-specific data.
+ *
+ * Called by regulator drivers to notify clients a regulator event has
+ * occurred.
+ */
+int regulator_notifier_call_chain(struct regulator_dev *rdev,
+				  unsigned long event, void *data)
+{
+	_notifier_call_chain(rdev, event, data);
+	return NOTIFY_DONE;
+
+}
+EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
+
+/**
+ * regulator_mode_to_status - convert a regulator mode into a status
+ *
+ * @mode: Mode to convert
+ *
+ * Convert a regulator mode into a status.
+ */
+int regulator_mode_to_status(unsigned int mode)
+{
+	switch (mode) {
+	case REGULATOR_MODE_FAST:
+		return REGULATOR_STATUS_FAST;
+	case REGULATOR_MODE_NORMAL:
+		return REGULATOR_STATUS_NORMAL;
+	case REGULATOR_MODE_IDLE:
+		return REGULATOR_STATUS_IDLE;
+	case REGULATOR_MODE_STANDBY:
+		return REGULATOR_STATUS_STANDBY;
+	default:
+		return REGULATOR_STATUS_UNDEFINED;
+	}
+}
+EXPORT_SYMBOL_GPL(regulator_mode_to_status);
+
+static struct attribute *regulator_dev_attrs[] = {
+	&dev_attr_name.attr,
+	&dev_attr_num_users.attr,
+	&dev_attr_type.attr,
+	&dev_attr_microvolts.attr,
+	&dev_attr_microamps.attr,
+	&dev_attr_opmode.attr,
+	&dev_attr_state.attr,
+	&dev_attr_status.attr,
+	&dev_attr_bypass.attr,
+	&dev_attr_requested_microamps.attr,
+	&dev_attr_min_microvolts.attr,
+	&dev_attr_max_microvolts.attr,
+	&dev_attr_min_microamps.attr,
+	&dev_attr_max_microamps.attr,
+	&dev_attr_suspend_standby_state.attr,
+	&dev_attr_suspend_mem_state.attr,
+	&dev_attr_suspend_disk_state.attr,
+	&dev_attr_suspend_standby_microvolts.attr,
+	&dev_attr_suspend_mem_microvolts.attr,
+	&dev_attr_suspend_disk_microvolts.attr,
+	&dev_attr_suspend_standby_mode.attr,
+	&dev_attr_suspend_mem_mode.attr,
+	&dev_attr_suspend_disk_mode.attr,
+	NULL
+};
+
+/*
+ * To avoid cluttering sysfs (and memory) with useless state, only
+ * create attributes that can be meaningfully displayed.
+ */
+static umode_t regulator_attr_is_visible(struct kobject *kobj,
+					 struct attribute *attr, int idx)
+{
+	struct device *dev = kobj_to_dev(kobj);
+	struct regulator_dev *rdev = dev_to_rdev(dev);
+	const struct regulator_ops *ops = rdev->desc->ops;
+	umode_t mode = attr->mode;
+
+	/* these three are always present */
+	if (attr == &dev_attr_name.attr ||
+	    attr == &dev_attr_num_users.attr ||
+	    attr == &dev_attr_type.attr)
+		return mode;
+
+	/* some attributes need specific methods to be displayed */
+	if (attr == &dev_attr_microvolts.attr) {
+		if ((ops->get_voltage && ops->get_voltage(rdev) >= 0) ||
+		    (ops->get_voltage_sel && ops->get_voltage_sel(rdev) >= 0) ||
+		    (ops->list_voltage && ops->list_voltage(rdev, 0) >= 0) ||
+		    (rdev->desc->fixed_uV && rdev->desc->n_voltages == 1))
+			return mode;
+		return 0;
+	}
+
+	if (attr == &dev_attr_microamps.attr)
+		return ops->get_current_limit ? mode : 0;
+
+	if (attr == &dev_attr_opmode.attr)
+		return ops->get_mode ? mode : 0;
+
+	if (attr == &dev_attr_state.attr)
+		return (rdev->ena_pin || ops->is_enabled) ? mode : 0;
+
+	if (attr == &dev_attr_status.attr)
+		return ops->get_status ? mode : 0;
+
+	if (attr == &dev_attr_bypass.attr)
+		return ops->get_bypass ? mode : 0;
+
+	/* constraints need specific supporting methods */
+	if (attr == &dev_attr_min_microvolts.attr ||
+	    attr == &dev_attr_max_microvolts.attr)
+		return (ops->set_voltage || ops->set_voltage_sel) ? mode : 0;
+
+	if (attr == &dev_attr_min_microamps.attr ||
+	    attr == &dev_attr_max_microamps.attr)
+		return ops->set_current_limit ? mode : 0;
+
+	if (attr == &dev_attr_suspend_standby_state.attr ||
+	    attr == &dev_attr_suspend_mem_state.attr ||
+	    attr == &dev_attr_suspend_disk_state.attr)
+		return mode;
+
+	if (attr == &dev_attr_suspend_standby_microvolts.attr ||
+	    attr == &dev_attr_suspend_mem_microvolts.attr ||
+	    attr == &dev_attr_suspend_disk_microvolts.attr)
+		return ops->set_suspend_voltage ? mode : 0;
+
+	if (attr == &dev_attr_suspend_standby_mode.attr ||
+	    attr == &dev_attr_suspend_mem_mode.attr ||
+	    attr == &dev_attr_suspend_disk_mode.attr)
+		return ops->set_suspend_mode ? mode : 0;
+
+	return mode;
+}
+
+static const struct attribute_group regulator_dev_group = {
+	.attrs = regulator_dev_attrs,
+	.is_visible = regulator_attr_is_visible,
+};
+
+static const struct attribute_group *regulator_dev_groups[] = {
+	&regulator_dev_group,
+	NULL
+};
+
+static void regulator_dev_release(struct device *dev)
+{
+	struct regulator_dev *rdev = dev_get_drvdata(dev);
+
+	debugfs_remove_recursive(rdev->debugfs);
+	kfree(rdev->constraints);
+	of_node_put(rdev->dev.of_node);
+	kfree(rdev);
+}
+
+static void rdev_init_debugfs(struct regulator_dev *rdev)
+{
+	struct device *parent = rdev->dev.parent;
+	const char *rname = rdev_get_name(rdev);
+	char name[NAME_MAX];
+
+	/* Avoid duplicate debugfs directory names */
+	if (parent && rname == rdev->desc->name) {
+		snprintf(name, sizeof(name), "%s-%s", dev_name(parent),
+			 rname);
+		rname = name;
+	}
+
+	rdev->debugfs = debugfs_create_dir(rname, debugfs_root);
+	if (IS_ERR(rdev->debugfs))
+		rdev_dbg(rdev, "Failed to create debugfs directory\n");
+
+	debugfs_create_u32("use_count", 0444, rdev->debugfs,
+			   &rdev->use_count);
+	debugfs_create_u32("open_count", 0444, rdev->debugfs,
+			   &rdev->open_count);
+	debugfs_create_u32("bypass_count", 0444, rdev->debugfs,
+			   &rdev->bypass_count);
+}
+
+static int regulator_register_resolve_supply(struct device *dev, void *data)
+{
+	struct regulator_dev *rdev = dev_to_rdev(dev);
+
+	if (regulator_resolve_supply(rdev))
+		rdev_dbg(rdev, "unable to resolve supply\n");
+
+	return 0;
+}
+
+int regulator_coupler_register(struct regulator_coupler *coupler)
+{
+	mutex_lock(&regulator_list_mutex);
+	list_add_tail(&coupler->list, &regulator_coupler_list);
+	mutex_unlock(&regulator_list_mutex);
+
+	return 0;
+}
+
+static struct regulator_coupler *
+regulator_find_coupler(struct regulator_dev *rdev)
+{
+	struct regulator_coupler *coupler;
+	int err;
+
+	/*
+	 * Note that regulators are appended to the list and the generic
+	 * coupler is registered first, hence it will be attached at last
+	 * if nobody cared.
+	 */
+	list_for_each_entry_reverse(coupler, &regulator_coupler_list, list) {
+		err = coupler->attach_regulator(coupler, rdev);
+		if (!err) {
+			if (!coupler->balance_voltage &&
+			    rdev->coupling_desc.n_coupled > 2)
+				goto err_unsupported;
+
+			return coupler;
+		}
+
+		if (err < 0)
+			return ERR_PTR(err);
+
+		if (err == 1)
+			continue;
+
+		break;
+	}
+
+	return ERR_PTR(-EINVAL);
+
+err_unsupported:
+	if (coupler->detach_regulator)
+		coupler->detach_regulator(coupler, rdev);
+
+	rdev_err(rdev,
+		"Voltage balancing for multiple regulator couples is unimplemented\n");
+
+	return ERR_PTR(-EPERM);
+}
+
+static void regulator_resolve_coupling(struct regulator_dev *rdev)
+{
+	struct regulator_coupler *coupler = rdev->coupling_desc.coupler;
+	struct coupling_desc *c_desc = &rdev->coupling_desc;
+	int n_coupled = c_desc->n_coupled;
+	struct regulator_dev *c_rdev;
+	int i;
+
+	for (i = 1; i < n_coupled; i++) {
+		/* already resolved */
+		if (c_desc->coupled_rdevs[i])
+			continue;
+
+		c_rdev = of_parse_coupled_regulator(rdev, i - 1);
+
+		if (!c_rdev)
+			continue;
+
+		if (c_rdev->coupling_desc.coupler != coupler) {
+			rdev_err(rdev, "coupler mismatch with %s\n",
+				 rdev_get_name(c_rdev));
+			return;
+		}
+
+		c_desc->coupled_rdevs[i] = c_rdev;
+		c_desc->n_resolved++;
+
+		regulator_resolve_coupling(c_rdev);
+	}
+}
+
+static void regulator_remove_coupling(struct regulator_dev *rdev)
+{
+	struct regulator_coupler *coupler = rdev->coupling_desc.coupler;
+	struct coupling_desc *__c_desc, *c_desc = &rdev->coupling_desc;
+	struct regulator_dev *__c_rdev, *c_rdev;
+	unsigned int __n_coupled, n_coupled;
+	int i, k;
+	int err;
+
+	n_coupled = c_desc->n_coupled;
+
+	for (i = 1; i < n_coupled; i++) {
+		c_rdev = c_desc->coupled_rdevs[i];
+
+		if (!c_rdev)
+			continue;
+
+		regulator_lock(c_rdev);
+
+		__c_desc = &c_rdev->coupling_desc;
+		__n_coupled = __c_desc->n_coupled;
+
+		for (k = 1; k < __n_coupled; k++) {
+			__c_rdev = __c_desc->coupled_rdevs[k];
+
+			if (__c_rdev == rdev) {
+				__c_desc->coupled_rdevs[k] = NULL;
+				__c_desc->n_resolved--;
+				break;
+			}
+		}
+
+		regulator_unlock(c_rdev);
+
+		c_desc->coupled_rdevs[i] = NULL;
+		c_desc->n_resolved--;
+	}
+
+	if (coupler && coupler->detach_regulator) {
+		err = coupler->detach_regulator(coupler, rdev);
+		if (err)
+			rdev_err(rdev, "failed to detach from coupler: %pe\n",
+				 ERR_PTR(err));
+	}
+
+	kfree(rdev->coupling_desc.coupled_rdevs);
+	rdev->coupling_desc.coupled_rdevs = NULL;
+}
+
+static int regulator_init_coupling(struct regulator_dev *rdev)
+{
+	struct regulator_dev **coupled;
+	int err, n_phandles;
+
+	if (!IS_ENABLED(CONFIG_OF))
+		n_phandles = 0;
+	else
+		n_phandles = of_get_n_coupled(rdev);
+
+	coupled = kcalloc(n_phandles + 1, sizeof(*coupled), GFP_KERNEL);
+	if (!coupled)
+		return -ENOMEM;
+
+	rdev->coupling_desc.coupled_rdevs = coupled;
+
+	/*
+	 * Every regulator should always have coupling descriptor filled with
+	 * at least pointer to itself.
+	 */
+	rdev->coupling_desc.coupled_rdevs[0] = rdev;
+	rdev->coupling_desc.n_coupled = n_phandles + 1;
+	rdev->coupling_desc.n_resolved++;
+
+	/* regulator isn't coupled */
+	if (n_phandles == 0)
+		return 0;
+
+	if (!of_check_coupling_data(rdev))
+		return -EPERM;
+
+	mutex_lock(&regulator_list_mutex);
+	rdev->coupling_desc.coupler = regulator_find_coupler(rdev);
+	mutex_unlock(&regulator_list_mutex);
+
+	if (IS_ERR(rdev->coupling_desc.coupler)) {
+		err = PTR_ERR(rdev->coupling_desc.coupler);
+		rdev_err(rdev, "failed to get coupler: %pe\n", ERR_PTR(err));
+		return err;
+	}
+
+	return 0;
+}
+
+static int generic_coupler_attach(struct regulator_coupler *coupler,
+				  struct regulator_dev *rdev)
+{
+	if (rdev->coupling_desc.n_coupled > 2) {
+		rdev_err(rdev,
+			 "Voltage balancing for multiple regulator couples is unimplemented\n");
+		return -EPERM;
+	}
+
+	if (!rdev->constraints->always_on) {
+		rdev_err(rdev,
+			 "Coupling of a non always-on regulator is unimplemented\n");
+		return -ENOTSUPP;
+	}
+
+	return 0;
+}
+
+static struct regulator_coupler generic_regulator_coupler = {
+	.attach_regulator = generic_coupler_attach,
+};
+
+/**
+ * regulator_register - register regulator
+ * @regulator_desc: regulator to register
+ * @cfg: runtime configuration for regulator
+ *
+ * Called by regulator drivers to register a regulator.
+ * Returns a valid pointer to struct regulator_dev on success
+ * or an ERR_PTR() on error.
+ */
+struct regulator_dev *
+regulator_register(const struct regulator_desc *regulator_desc,
+		   const struct regulator_config *cfg)
+{
+	const struct regulator_init_data *init_data;
+	struct regulator_config *config = NULL;
+	static atomic_t regulator_no = ATOMIC_INIT(-1);
+	struct regulator_dev *rdev;
+	bool dangling_cfg_gpiod = false;
+	bool dangling_of_gpiod = false;
+	struct device *dev;
+	int ret, i;
+
+	if (cfg == NULL)
+		return ERR_PTR(-EINVAL);
+	if (cfg->ena_gpiod)
+		dangling_cfg_gpiod = true;
+	if (regulator_desc == NULL) {
+		ret = -EINVAL;
+		goto rinse;
+	}
+
+	dev = cfg->dev;
+	WARN_ON(!dev);
+
+	if (regulator_desc->name == NULL || regulator_desc->ops == NULL) {
+		ret = -EINVAL;
+		goto rinse;
+	}
+
+	if (regulator_desc->type != REGULATOR_VOLTAGE &&
+	    regulator_desc->type != REGULATOR_CURRENT) {
+		ret = -EINVAL;
+		goto rinse;
+	}
+
+	/* Only one of each should be implemented */
+	WARN_ON(regulator_desc->ops->get_voltage &&
+		regulator_desc->ops->get_voltage_sel);
+	WARN_ON(regulator_desc->ops->set_voltage &&
+		regulator_desc->ops->set_voltage_sel);
+
+	/* If we're using selectors we must implement list_voltage. */
+	if (regulator_desc->ops->get_voltage_sel &&
+	    !regulator_desc->ops->list_voltage) {
+		ret = -EINVAL;
+		goto rinse;
+	}
+	if (regulator_desc->ops->set_voltage_sel &&
+	    !regulator_desc->ops->list_voltage) {
+		ret = -EINVAL;
+		goto rinse;
+	}
+
+	rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
+	if (rdev == NULL) {
+		ret = -ENOMEM;
+		goto rinse;
+	}
+	device_initialize(&rdev->dev);
+
+	/*
+	 * Duplicate the config so the driver could override it after
+	 * parsing init data.
+	 */
+	config = kmemdup(cfg, sizeof(*cfg), GFP_KERNEL);
+	if (config == NULL) {
+		ret = -ENOMEM;
+		goto clean;
+	}
+
+	init_data = regulator_of_get_init_data(dev, regulator_desc, config,
+					       &rdev->dev.of_node);
+
+	/*
+	 * Sometimes not all resources are probed already so we need to take
+	 * that into account. This happens most the time if the ena_gpiod comes
+	 * from a gpio extender or something else.
+	 */
+	if (PTR_ERR(init_data) == -EPROBE_DEFER) {
+		ret = -EPROBE_DEFER;
+		goto clean;
+	}
+
+	/*
+	 * We need to keep track of any GPIO descriptor coming from the
+	 * device tree until we have handled it over to the core. If the
+	 * config that was passed in to this function DOES NOT contain
+	 * a descriptor, and the config after this call DOES contain
+	 * a descriptor, we definitely got one from parsing the device
+	 * tree.
+	 */
+	if (!cfg->ena_gpiod && config->ena_gpiod)
+		dangling_of_gpiod = true;
+	if (!init_data) {
+		init_data = config->init_data;
+		rdev->dev.of_node = of_node_get(config->of_node);
+	}
+
+	ww_mutex_init(&rdev->mutex, &regulator_ww_class);
+	rdev->reg_data = config->driver_data;
+	rdev->owner = regulator_desc->owner;
+	rdev->desc = regulator_desc;
+	if (config->regmap)
+		rdev->regmap = config->regmap;
+	else if (dev_get_regmap(dev, NULL))
+		rdev->regmap = dev_get_regmap(dev, NULL);
+	else if (dev->parent)
+		rdev->regmap = dev_get_regmap(dev->parent, NULL);
+	INIT_LIST_HEAD(&rdev->consumer_list);
+	INIT_LIST_HEAD(&rdev->list);
+	BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
+	INIT_DELAYED_WORK(&rdev->disable_work, regulator_disable_work);
+
+	/* preform any regulator specific init */
+	if (init_data && init_data->regulator_init) {
+		ret = init_data->regulator_init(rdev->reg_data);
+		if (ret < 0)
+			goto clean;
+	}
+
+	if (config->ena_gpiod) {
+		ret = regulator_ena_gpio_request(rdev, config);
+		if (ret != 0) {
+			rdev_err(rdev, "Failed to request enable GPIO: %pe\n",
+				 ERR_PTR(ret));
+			goto clean;
+		}
+		/* The regulator core took over the GPIO descriptor */
+		dangling_cfg_gpiod = false;
+		dangling_of_gpiod = false;
+	}
+
+	/* register with sysfs */
+	rdev->dev.class = &regulator_class;
+	rdev->dev.parent = dev;
+	dev_set_name(&rdev->dev, "regulator.%lu",
+		    (unsigned long) atomic_inc_return(&regulator_no));
+	dev_set_drvdata(&rdev->dev, rdev);
+
+	/* set regulator constraints */
+	if (init_data)
+		rdev->constraints = kmemdup(&init_data->constraints,
+					    sizeof(*rdev->constraints),
+					    GFP_KERNEL);
+	else
+		rdev->constraints = kzalloc(sizeof(*rdev->constraints),
+					    GFP_KERNEL);
+	if (!rdev->constraints) {
+		ret = -ENOMEM;
+		goto wash;
+	}
+
+	if (init_data && init_data->supply_regulator)
+		rdev->supply_name = init_data->supply_regulator;
+	else if (regulator_desc->supply_name)
+		rdev->supply_name = regulator_desc->supply_name;
+
+	ret = set_machine_constraints(rdev);
+	if (ret == -EPROBE_DEFER) {
+		/* Regulator might be in bypass mode and so needs its supply
+		 * to set the constraints */
+		/* FIXME: this currently triggers a chicken-and-egg problem
+		 * when creating -SUPPLY symlink in sysfs to a regulator
+		 * that is just being created */
+		ret = regulator_resolve_supply(rdev);
+		if (!ret)
+			ret = set_machine_constraints(rdev);
+		else
+			rdev_dbg(rdev, "unable to resolve supply early: %pe\n",
+				 ERR_PTR(ret));
+	}
+	if (ret < 0)
+		goto wash;
+
+	ret = regulator_init_coupling(rdev);
+	if (ret < 0)
+		goto wash;
+
+	/* add consumers devices */
+	if (init_data) {
+		for (i = 0; i < init_data->num_consumer_supplies; i++) {
+			ret = set_consumer_device_supply(rdev,
+				init_data->consumer_supplies[i].dev_name,
+				init_data->consumer_supplies[i].supply);
+			if (ret < 0) {
+				dev_err(dev, "Failed to set supply %s\n",
+					init_data->consumer_supplies[i].supply);
+				goto unset_supplies;
+			}
+		}
+	}
+
+	if (!rdev->desc->ops->get_voltage &&
+	    !rdev->desc->ops->list_voltage &&
+	    !rdev->desc->fixed_uV)
+		rdev->is_switch = true;
+
+	ret = device_add(&rdev->dev);
+	if (ret != 0)
+		goto unset_supplies;
+
+	rdev_init_debugfs(rdev);
+
+	/* try to resolve regulators coupling since a new one was registered */
+	mutex_lock(&regulator_list_mutex);
+	regulator_resolve_coupling(rdev);
+	mutex_unlock(&regulator_list_mutex);
+
+	/* try to resolve regulators supply since a new one was registered */
+	class_for_each_device(&regulator_class, NULL, NULL,
+			      regulator_register_resolve_supply);
+	kfree(config);
+	return rdev;
+
+unset_supplies:
+	mutex_lock(&regulator_list_mutex);
+	unset_regulator_supplies(rdev);
+	regulator_remove_coupling(rdev);
+	mutex_unlock(&regulator_list_mutex);
+wash:
+	regulator_put(rdev->supply);
+	kfree(rdev->coupling_desc.coupled_rdevs);
+	mutex_lock(&regulator_list_mutex);
+	regulator_ena_gpio_free(rdev);
+	mutex_unlock(&regulator_list_mutex);
+clean:
+	if (dangling_of_gpiod)
+		gpiod_put(config->ena_gpiod);
+	kfree(config);
+	put_device(&rdev->dev);
+rinse:
+	if (dangling_cfg_gpiod)
+		gpiod_put(cfg->ena_gpiod);
+	return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(regulator_register);
+
+/**
+ * regulator_unregister - unregister regulator
+ * @rdev: regulator to unregister
+ *
+ * Called by regulator drivers to unregister a regulator.
+ */
+void regulator_unregister(struct regulator_dev *rdev)
+{
+	if (rdev == NULL)
+		return;
+
+	if (rdev->supply) {
+		while (rdev->use_count--)
+			regulator_disable(rdev->supply);
+		regulator_put(rdev->supply);
+	}
+
+	flush_work(&rdev->disable_work.work);
+
+	mutex_lock(&regulator_list_mutex);
+
+	WARN_ON(rdev->open_count);
+	regulator_remove_coupling(rdev);
+	unset_regulator_supplies(rdev);
+	list_del(&rdev->list);
+	regulator_ena_gpio_free(rdev);
+	device_unregister(&rdev->dev);
+
+	mutex_unlock(&regulator_list_mutex);
+}
+EXPORT_SYMBOL_GPL(regulator_unregister);
+
+#ifdef CONFIG_SUSPEND
+/**
+ * regulator_suspend - prepare regulators for system wide suspend
+ * @dev: ``&struct device`` pointer that is passed to _regulator_suspend()
+ *
+ * Configure each regulator with it's suspend operating parameters for state.
+ */
+static int regulator_suspend(struct device *dev)
+{
+	struct regulator_dev *rdev = dev_to_rdev(dev);
+	suspend_state_t state = pm_suspend_target_state;
+	int ret;
+	const struct regulator_state *rstate;
+
+	rstate = regulator_get_suspend_state_check(rdev, state);
+	if (!rstate)
+		return 0;
+
+	regulator_lock(rdev);
+	ret = __suspend_set_state(rdev, rstate);
+	regulator_unlock(rdev);
+
+	return ret;
+}
+
+static int regulator_resume(struct device *dev)
+{
+	suspend_state_t state = pm_suspend_target_state;
+	struct regulator_dev *rdev = dev_to_rdev(dev);
+	struct regulator_state *rstate;
+	int ret = 0;
+
+	rstate = regulator_get_suspend_state(rdev, state);
+	if (rstate == NULL)
+		return 0;
+
+	/* Avoid grabbing the lock if we don't need to */
+	if (!rdev->desc->ops->resume)
+		return 0;
+
+	regulator_lock(rdev);
+
+	if (rstate->enabled == ENABLE_IN_SUSPEND ||
+	    rstate->enabled == DISABLE_IN_SUSPEND)
+		ret = rdev->desc->ops->resume(rdev);
+
+	regulator_unlock(rdev);
+
+	return ret;
+}
+#else /* !CONFIG_SUSPEND */
+
+#define regulator_suspend	NULL
+#define regulator_resume	NULL
+
+#endif /* !CONFIG_SUSPEND */
+
+#ifdef CONFIG_PM
+static const struct dev_pm_ops __maybe_unused regulator_pm_ops = {
+	.suspend	= regulator_suspend,
+	.resume		= regulator_resume,
+};
+#endif
+
+struct class regulator_class = {
+	.name = "regulator",
+	.dev_release = regulator_dev_release,
+	.dev_groups = regulator_dev_groups,
+#ifdef CONFIG_PM
+	.pm = &regulator_pm_ops,
+#endif
+};
+/**
+ * regulator_has_full_constraints - the system has fully specified constraints
+ *
+ * Calling this function will cause the regulator API to disable all
+ * regulators which have a zero use count and don't have an always_on
+ * constraint in a late_initcall.
+ *
+ * The intention is that this will become the default behaviour in a
+ * future kernel release so users are encouraged to use this facility
+ * now.
+ */
+void regulator_has_full_constraints(void)
+{
+	has_full_constraints = 1;
+}
+EXPORT_SYMBOL_GPL(regulator_has_full_constraints);
+
+/**
+ * rdev_get_drvdata - get rdev regulator driver data
+ * @rdev: regulator
+ *
+ * Get rdev regulator driver private data. This call can be used in the
+ * regulator driver context.
+ */
+void *rdev_get_drvdata(struct regulator_dev *rdev)
+{
+	return rdev->reg_data;
+}
+EXPORT_SYMBOL_GPL(rdev_get_drvdata);
+
+/**
+ * regulator_get_drvdata - get regulator driver data
+ * @regulator: regulator
+ *
+ * Get regulator driver private data. This call can be used in the consumer
+ * driver context when non API regulator specific functions need to be called.
+ */
+void *regulator_get_drvdata(struct regulator *regulator)
+{
+	return regulator->rdev->reg_data;
+}
+EXPORT_SYMBOL_GPL(regulator_get_drvdata);
+
+/**
+ * regulator_set_drvdata - set regulator driver data
+ * @regulator: regulator
+ * @data: data
+ */
+void regulator_set_drvdata(struct regulator *regulator, void *data)
+{
+	regulator->rdev->reg_data = data;
+}
+EXPORT_SYMBOL_GPL(regulator_set_drvdata);
+
+/**
+ * regulator_get_id - get regulator ID
+ * @rdev: regulator
+ */
+int rdev_get_id(struct regulator_dev *rdev)
+{
+	return rdev->desc->id;
+}
+EXPORT_SYMBOL_GPL(rdev_get_id);
+
+struct device *rdev_get_dev(struct regulator_dev *rdev)
+{
+	return &rdev->dev;
+}
+EXPORT_SYMBOL_GPL(rdev_get_dev);
+
+struct regmap *rdev_get_regmap(struct regulator_dev *rdev)
+{
+	return rdev->regmap;
+}
+EXPORT_SYMBOL_GPL(rdev_get_regmap);
+
+void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
+{
+	return reg_init_data->driver_data;
+}
+EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
+
+#ifdef CONFIG_DEBUG_FS
+static int supply_map_show(struct seq_file *sf, void *data)
+{
+	struct regulator_map *map;
+
+	list_for_each_entry(map, &regulator_map_list, list) {
+		seq_printf(sf, "%s -> %s.%s\n",
+				rdev_get_name(map->regulator), map->dev_name,
+				map->supply);
+	}
+
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(supply_map);
+
+struct summary_data {
+	struct seq_file *s;
+	struct regulator_dev *parent;
+	int level;
+};
+
+static void regulator_summary_show_subtree(struct seq_file *s,
+					   struct regulator_dev *rdev,
+					   int level);
+
+static int regulator_summary_show_children(struct device *dev, void *data)
+{
+	struct regulator_dev *rdev = dev_to_rdev(dev);
+	struct summary_data *summary_data = data;
+
+	if (rdev->supply && rdev->supply->rdev == summary_data->parent)
+		regulator_summary_show_subtree(summary_data->s, rdev,
+					       summary_data->level + 1);
+
+	return 0;
+}
+
+static void regulator_summary_show_subtree(struct seq_file *s,
+					   struct regulator_dev *rdev,
+					   int level)
+{
+	struct regulation_constraints *c;
+	struct regulator *consumer;
+	struct summary_data summary_data;
+	unsigned int opmode;
+
+	if (!rdev)
+		return;
+
+	opmode = _regulator_get_mode_unlocked(rdev);
+	seq_printf(s, "%*s%-*s %3d %4d %6d %7s ",
+		   level * 3 + 1, "",
+		   30 - level * 3, rdev_get_name(rdev),
+		   rdev->use_count, rdev->open_count, rdev->bypass_count,
+		   regulator_opmode_to_str(opmode));
+
+	seq_printf(s, "%5dmV ", regulator_get_voltage_rdev(rdev) / 1000);
+	seq_printf(s, "%5dmA ",
+		   _regulator_get_current_limit_unlocked(rdev) / 1000);
+
+	c = rdev->constraints;
+	if (c) {
+		switch (rdev->desc->type) {
+		case REGULATOR_VOLTAGE:
+			seq_printf(s, "%5dmV %5dmV ",
+				   c->min_uV / 1000, c->max_uV / 1000);
+			break;
+		case REGULATOR_CURRENT:
+			seq_printf(s, "%5dmA %5dmA ",
+				   c->min_uA / 1000, c->max_uA / 1000);
+			break;
+		}
+	}
+
+	seq_puts(s, "\n");
+
+	list_for_each_entry(consumer, &rdev->consumer_list, list) {
+		if (consumer->dev && consumer->dev->class == &regulator_class)
+			continue;
+
+		seq_printf(s, "%*s%-*s ",
+			   (level + 1) * 3 + 1, "",
+			   30 - (level + 1) * 3,
+			   consumer->supply_name ? consumer->supply_name :
+			   consumer->dev ? dev_name(consumer->dev) : "deviceless");
+
+		switch (rdev->desc->type) {
+		case REGULATOR_VOLTAGE:
+			seq_printf(s, "%3d %33dmA%c%5dmV %5dmV",
+				   consumer->enable_count,
+				   consumer->uA_load / 1000,
+				   consumer->uA_load && !consumer->enable_count ?
+				   '*' : ' ',
+				   consumer->voltage[PM_SUSPEND_ON].min_uV / 1000,
+				   consumer->voltage[PM_SUSPEND_ON].max_uV / 1000);
+			break;
+		case REGULATOR_CURRENT:
+			break;
+		}
+
+		seq_puts(s, "\n");
+	}
+
+	summary_data.s = s;
+	summary_data.level = level;
+	summary_data.parent = rdev;
+
+	class_for_each_device(&regulator_class, NULL, &summary_data,
+			      regulator_summary_show_children);
+}
+
+struct summary_lock_data {
+	struct ww_acquire_ctx *ww_ctx;
+	struct regulator_dev **new_contended_rdev;
+	struct regulator_dev **old_contended_rdev;
+};
+
+static int regulator_summary_lock_one(struct device *dev, void *data)
+{
+	struct regulator_dev *rdev = dev_to_rdev(dev);
+	struct summary_lock_data *lock_data = data;
+	int ret = 0;
+
+	if (rdev != *lock_data->old_contended_rdev) {
+		ret = regulator_lock_nested(rdev, lock_data->ww_ctx);
+
+		if (ret == -EDEADLK)
+			*lock_data->new_contended_rdev = rdev;
+		else
+			WARN_ON_ONCE(ret);
+	} else {
+		*lock_data->old_contended_rdev = NULL;
+	}
+
+	return ret;
+}
+
+static int regulator_summary_unlock_one(struct device *dev, void *data)
+{
+	struct regulator_dev *rdev = dev_to_rdev(dev);
+	struct summary_lock_data *lock_data = data;
+
+	if (lock_data) {
+		if (rdev == *lock_data->new_contended_rdev)
+			return -EDEADLK;
+	}
+
+	regulator_unlock(rdev);
+
+	return 0;
+}
+
+static int regulator_summary_lock_all(struct ww_acquire_ctx *ww_ctx,
+				      struct regulator_dev **new_contended_rdev,
+				      struct regulator_dev **old_contended_rdev)
+{
+	struct summary_lock_data lock_data;
+	int ret;
+
+	lock_data.ww_ctx = ww_ctx;
+	lock_data.new_contended_rdev = new_contended_rdev;
+	lock_data.old_contended_rdev = old_contended_rdev;
+
+	ret = class_for_each_device(&regulator_class, NULL, &lock_data,
+				    regulator_summary_lock_one);
+	if (ret)
+		class_for_each_device(&regulator_class, NULL, &lock_data,
+				      regulator_summary_unlock_one);
+
+	return ret;
+}
+
+static void regulator_summary_lock(struct ww_acquire_ctx *ww_ctx)
+{
+	struct regulator_dev *new_contended_rdev = NULL;
+	struct regulator_dev *old_contended_rdev = NULL;
+	int err;
+
+	mutex_lock(&regulator_list_mutex);
+
+	ww_acquire_init(ww_ctx, &regulator_ww_class);
+
+	do {
+		if (new_contended_rdev) {
+			ww_mutex_lock_slow(&new_contended_rdev->mutex, ww_ctx);
+			old_contended_rdev = new_contended_rdev;
+			old_contended_rdev->ref_cnt++;
+			old_contended_rdev->mutex_owner = current;
+		}
+
+		err = regulator_summary_lock_all(ww_ctx,
+						 &new_contended_rdev,
+						 &old_contended_rdev);
+
+		if (old_contended_rdev)
+			regulator_unlock(old_contended_rdev);
+
+	} while (err == -EDEADLK);
+
+	ww_acquire_done(ww_ctx);
+}
+
+static void regulator_summary_unlock(struct ww_acquire_ctx *ww_ctx)
+{
+	class_for_each_device(&regulator_class, NULL, NULL,
+			      regulator_summary_unlock_one);
+	ww_acquire_fini(ww_ctx);
+
+	mutex_unlock(&regulator_list_mutex);
+}
+
+static int regulator_summary_show_roots(struct device *dev, void *data)
+{
+	struct regulator_dev *rdev = dev_to_rdev(dev);
+	struct seq_file *s = data;
+
+	if (!rdev->supply)
+		regulator_summary_show_subtree(s, rdev, 0);
+
+	return 0;
+}
+
+static int regulator_summary_show(struct seq_file *s, void *data)
+{
+	struct ww_acquire_ctx ww_ctx;
+
+	seq_puts(s, " regulator                      use open bypass  opmode voltage current     min     max\n");
+	seq_puts(s, "---------------------------------------------------------------------------------------\n");
+
+	regulator_summary_lock(&ww_ctx);
+
+	class_for_each_device(&regulator_class, NULL, s,
+			      regulator_summary_show_roots);
+
+	regulator_summary_unlock(&ww_ctx);
+
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(regulator_summary);
+#endif /* CONFIG_DEBUG_FS */
+
+static int __init regulator_init(void)
+{
+	int ret;
+
+	ret = class_register(&regulator_class);
+
+	debugfs_root = debugfs_create_dir("regulator", NULL);
+	if (IS_ERR(debugfs_root))
+		pr_debug("regulator: Failed to create debugfs directory\n");
+
+#ifdef CONFIG_DEBUG_FS
+	debugfs_create_file("supply_map", 0444, debugfs_root, NULL,
+			    &supply_map_fops);
+
+	debugfs_create_file("regulator_summary", 0444, debugfs_root,
+			    NULL, &regulator_summary_fops);
+#endif
+	regulator_dummy_init();
+
+	regulator_coupler_register(&generic_regulator_coupler);
+
+	return ret;
+}
+
+/* init early to allow our consumers to complete system booting */
+core_initcall(regulator_init);
+
+static int regulator_late_cleanup(struct device *dev, void *data)
+{
+	struct regulator_dev *rdev = dev_to_rdev(dev);
+	struct regulation_constraints *c = rdev->constraints;
+	int ret;
+
+	if (c && c->always_on)
+		return 0;
+
+	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_STATUS))
+		return 0;
+
+	regulator_lock(rdev);
+
+	if (rdev->use_count)
+		goto unlock;
+
+	/* If reading the status failed, assume that it's off. */
+	if (_regulator_is_enabled(rdev) <= 0)
+		goto unlock;
+
+	if (have_full_constraints()) {
+		/* We log since this may kill the system if it goes
+		 * wrong. */
+		rdev_info(rdev, "disabling\n");
+		ret = _regulator_do_disable(rdev);
+		if (ret != 0)
+			rdev_err(rdev, "couldn't disable: %pe\n", ERR_PTR(ret));
+	} else {
+		/* The intention is that in future we will
+		 * assume that full constraints are provided
+		 * so warn even if we aren't going to do
+		 * anything here.
+		 */
+		rdev_warn(rdev, "incomplete constraints, leaving on\n");
+	}
+
+unlock:
+	regulator_unlock(rdev);
+
+	return 0;
+}
+
+static void regulator_init_complete_work_function(struct work_struct *work)
+{
+	/*
+	 * Regulators may had failed to resolve their input supplies
+	 * when were registered, either because the input supply was
+	 * not registered yet or because its parent device was not
+	 * bound yet. So attempt to resolve the input supplies for
+	 * pending regulators before trying to disable unused ones.
+	 */
+	class_for_each_device(&regulator_class, NULL, NULL,
+			      regulator_register_resolve_supply);
+
+	/* If we have a full configuration then disable any regulators
+	 * we have permission to change the status for and which are
+	 * not in use or always_on.  This is effectively the default
+	 * for DT and ACPI as they have full constraints.
+	 */
+	class_for_each_device(&regulator_class, NULL, NULL,
+			      regulator_late_cleanup);
+}
+
+static DECLARE_DELAYED_WORK(regulator_init_complete_work,
+			    regulator_init_complete_work_function);
+
+static int __init regulator_init_complete(void)
+{
+	/*
+	 * Since DT doesn't provide an idiomatic mechanism for
+	 * enabling full constraints and since it's much more natural
+	 * with DT to provide them just assume that a DT enabled
+	 * system has full constraints.
+	 */
+	if (of_have_populated_dt())
+		has_full_constraints = true;
+
+	/*
+	 * We punt completion for an arbitrary amount of time since
+	 * systems like distros will load many drivers from userspace
+	 * so consumers might not always be ready yet, this is
+	 * particularly an issue with laptops where this might bounce
+	 * the display off then on.  Ideally we'd get a notification
+	 * from userspace when this happens but we don't so just wait
+	 * a bit and hope we waited long enough.  It'd be better if
+	 * we'd only do this on systems that need it, and a kernel
+	 * command line option might be useful.
+	 */
+	schedule_delayed_work(&regulator_init_complete_work,
+			      msecs_to_jiffies(30000));
+
+	return 0;
+}
+late_initcall_sync(regulator_init_complete);