Initial import of modified Linux 2.6.28 tree

Original upstream URL:
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git | branch linux-2.6.28.y

1 files changed, 1949 insertions, 0 deletions

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
new file mode 100644
index 0000000..02a7744
--- /dev/null
+++ b/drivers/regulator/core.c
@@ -0,0 +1,1949 @@
+/*
+ * core.c  --  Voltage/Current Regulator framework.
+ *
+ * Copyright 2007, 2008 Wolfson Microelectronics PLC.
+ * Copyright 2008 SlimLogic Ltd.
+ *
+ * Author: Liam Girdwood <lrg@slimlogic.co.uk>
+ *
+ *  This program is free software; you can redistribute  it and/or modify it
+ *  under  the terms of  the GNU General  Public License as published by the
+ *  Free Software Foundation;  either version 2 of the  License, or (at your
+ *  option) any later version.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/mutex.h>
+#include <linux/suspend.h>
+#include <linux/regulator/consumer.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+
+#define REGULATOR_VERSION "0.5"
+
+static DEFINE_MUTEX(regulator_list_mutex);
+static LIST_HEAD(regulator_list);
+static LIST_HEAD(regulator_map_list);
+
+/**
+ * struct regulator_dev
+ *
+ * Voltage / Current regulator class device. One for each regulator.
+ */
+struct regulator_dev {
+	struct regulator_desc *desc;
+	int use_count;
+
+	/* lists we belong to */
+	struct list_head list; /* list of all regulators */
+	struct list_head slist; /* list of supplied regulators */
+
+	/* lists we own */
+	struct list_head consumer_list; /* consumers we supply */
+	struct list_head supply_list; /* regulators we supply */
+
+	struct blocking_notifier_head notifier;
+	struct mutex mutex; /* consumer lock */
+	struct module *owner;
+	struct device dev;
+	struct regulation_constraints *constraints;
+	struct regulator_dev *supply;	/* for tree */
+
+	void *reg_data;		/* regulator_dev data */
+};
+
+/**
+ * struct regulator_map
+ *
+ * Used to provide symbolic supply names to devices.
+ */
+struct regulator_map {
+	struct list_head list;
+	struct device *dev;
+	const char *supply;
+	struct regulator_dev *regulator;
+};
+
+/*
+ * struct regulator
+ *
+ * One for each consumer device.
+ */
+struct regulator {
+	struct device *dev;
+	struct list_head list;
+	int uA_load;
+	int min_uV;
+	int max_uV;
+	int enabled; /* client has called enabled */
+	char *supply_name;
+	struct device_attribute dev_attr;
+	struct regulator_dev *rdev;
+};
+
+static int _regulator_is_enabled(struct regulator_dev *rdev);
+static int _regulator_disable(struct regulator_dev *rdev);
+static int _regulator_get_voltage(struct regulator_dev *rdev);
+static int _regulator_get_current_limit(struct regulator_dev *rdev);
+static unsigned int _regulator_get_mode(struct regulator_dev *rdev);
+static void _notifier_call_chain(struct regulator_dev *rdev,
+				  unsigned long event, void *data);
+
+/* gets the regulator for a given consumer device */
+static struct regulator *get_device_regulator(struct device *dev)
+{
+	struct regulator *regulator = NULL;
+	struct regulator_dev *rdev;
+
+	mutex_lock(&regulator_list_mutex);
+	list_for_each_entry(rdev, &regulator_list, list) {
+		mutex_lock(&rdev->mutex);
+		list_for_each_entry(regulator, &rdev->consumer_list, list) {
+			if (regulator->dev == dev) {
+				mutex_unlock(&rdev->mutex);
+				mutex_unlock(&regulator_list_mutex);
+				return regulator;
+			}
+		}
+		mutex_unlock(&rdev->mutex);
+	}
+	mutex_unlock(&regulator_list_mutex);
+	return NULL;
+}
+
+/* Platform voltage constraint check */
+static int regulator_check_voltage(struct regulator_dev *rdev,
+				   int *min_uV, int *max_uV)
+{
+	BUG_ON(*min_uV > *max_uV);
+
+	if (!rdev->constraints) {
+		printk(KERN_ERR "%s: no constraints for %s\n", __func__,
+		       rdev->desc->name);
+		return -ENODEV;
+	}
+	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
+		printk(KERN_ERR "%s: operation not allowed for %s\n",
+		       __func__, rdev->desc->name);
+		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)
+		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 (!rdev->constraints) {
+		printk(KERN_ERR "%s: no constraints for %s\n", __func__,
+		       rdev->desc->name);
+		return -ENODEV;
+	}
+	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_CURRENT)) {
+		printk(KERN_ERR "%s: operation not allowed for %s\n",
+		       __func__, rdev->desc->name);
+		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)
+		return -EINVAL;
+
+	return 0;
+}
+
+/* operating mode constraint check */
+static int regulator_check_mode(struct regulator_dev *rdev, int mode)
+{
+	if (!rdev->constraints) {
+		printk(KERN_ERR "%s: no constraints for %s\n", __func__,
+		       rdev->desc->name);
+		return -ENODEV;
+	}
+	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_MODE)) {
+		printk(KERN_ERR "%s: operation not allowed for %s\n",
+		       __func__, rdev->desc->name);
+		return -EPERM;
+	}
+	if (!(rdev->constraints->valid_modes_mask & mode)) {
+		printk(KERN_ERR "%s: invalid mode %x for %s\n",
+		       __func__, mode, rdev->desc->name);
+		return -EINVAL;
+	}
+	return 0;
+}
+
+/* dynamic regulator mode switching constraint check */
+static int regulator_check_drms(struct regulator_dev *rdev)
+{
+	if (!rdev->constraints) {
+		printk(KERN_ERR "%s: no constraints for %s\n", __func__,
+		       rdev->desc->name);
+		return -ENODEV;
+	}
+	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS)) {
+		printk(KERN_ERR "%s: operation not allowed for %s\n",
+		       __func__, rdev->desc->name);
+		return -EPERM;
+	}
+	return 0;
+}
+
+static ssize_t device_requested_uA_show(struct device *dev,
+			     struct device_attribute *attr, char *buf)
+{
+	struct regulator *regulator;
+
+	regulator = get_device_regulator(dev);
+	if (regulator == NULL)
+		return 0;
+
+	return sprintf(buf, "%d\n", regulator->uA_load);
+}
+
+static ssize_t regulator_uV_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct regulator_dev *rdev = dev_get_drvdata(dev);
+	ssize_t ret;
+
+	mutex_lock(&rdev->mutex);
+	ret = sprintf(buf, "%d\n", _regulator_get_voltage(rdev));
+	mutex_unlock(&rdev->mutex);
+
+	return ret;
+}
+
+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 ssize_t regulator_name_show(struct device *dev,
+			     struct device_attribute *attr, char *buf)
+{
+	struct regulator_dev *rdev = dev_get_drvdata(dev);
+	const char *name;
+
+	if (rdev->constraints->name)
+		name = rdev->constraints->name;
+	else if (rdev->desc->name)
+		name = rdev->desc->name;
+	else
+		name = "";
+
+	return sprintf(buf, "%s\n", name);
+}
+
+static ssize_t regulator_opmode_show(struct device *dev,
+				    struct device_attribute *attr, char *buf)
+{
+	struct regulator_dev *rdev = dev_get_drvdata(dev);
+	int mode = _regulator_get_mode(rdev);
+
+	switch (mode) {
+	case REGULATOR_MODE_FAST:
+		return sprintf(buf, "fast\n");
+	case REGULATOR_MODE_NORMAL:
+		return sprintf(buf, "normal\n");
+	case REGULATOR_MODE_IDLE:
+		return sprintf(buf, "idle\n");
+	case REGULATOR_MODE_STANDBY:
+		return sprintf(buf, "standby\n");
+	}
+	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);
+	int state = _regulator_is_enabled(rdev);
+
+	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_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 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 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 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 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;
+
+	mutex_lock(&rdev->mutex);
+	list_for_each_entry(regulator, &rdev->consumer_list, list)
+	    uA += regulator->uA_load;
+	mutex_unlock(&rdev->mutex);
+	return sprintf(buf, "%d\n", uA);
+}
+
+static ssize_t regulator_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 ssize_t regulator_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 ssize_t regulator_suspend_mem_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, "not defined\n");
+	return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
+}
+
+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);
+
+	if (!rdev->constraints)
+		return sprintf(buf, "not defined\n");
+	return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
+}
+
+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);
+
+	if (!rdev->constraints)
+		return sprintf(buf, "not defined\n");
+	return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
+}
+
+static ssize_t suspend_opmode_show(struct regulator_dev *rdev,
+	unsigned int mode, char *buf)
+{
+	switch (mode) {
+	case REGULATOR_MODE_FAST:
+		return sprintf(buf, "fast\n");
+	case REGULATOR_MODE_NORMAL:
+		return sprintf(buf, "normal\n");
+	case REGULATOR_MODE_IDLE:
+		return sprintf(buf, "idle\n");
+	case REGULATOR_MODE_STANDBY:
+		return sprintf(buf, "standby\n");
+	}
+	return sprintf(buf, "unknown\n");
+}
+
+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);
+
+	if (!rdev->constraints)
+		return sprintf(buf, "not defined\n");
+	return suspend_opmode_show(rdev,
+		rdev->constraints->state_mem.mode, buf);
+}
+
+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);
+
+	if (!rdev->constraints)
+		return sprintf(buf, "not defined\n");
+	return suspend_opmode_show(rdev,
+		rdev->constraints->state_disk.mode, buf);
+}
+
+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);
+
+	if (!rdev->constraints)
+		return sprintf(buf, "not defined\n");
+	return suspend_opmode_show(rdev,
+		rdev->constraints->state_standby.mode, buf);
+}
+
+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);
+
+	if (!rdev->constraints)
+		return sprintf(buf, "not defined\n");
+
+	if (rdev->constraints->state_mem.enabled)
+		return sprintf(buf, "enabled\n");
+	else
+		return sprintf(buf, "disabled\n");
+}
+
+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);
+
+	if (!rdev->constraints)
+		return sprintf(buf, "not defined\n");
+
+	if (rdev->constraints->state_disk.enabled)
+		return sprintf(buf, "enabled\n");
+	else
+		return sprintf(buf, "disabled\n");
+}
+
+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);
+
+	if (!rdev->constraints)
+		return sprintf(buf, "not defined\n");
+
+	if (rdev->constraints->state_standby.enabled)
+		return sprintf(buf, "enabled\n");
+	else
+		return sprintf(buf, "disabled\n");
+}
+
+static struct device_attribute regulator_dev_attrs[] = {
+	__ATTR(name, 0444, regulator_name_show, NULL),
+	__ATTR(microvolts, 0444, regulator_uV_show, NULL),
+	__ATTR(microamps, 0444, regulator_uA_show, NULL),
+	__ATTR(opmode, 0444, regulator_opmode_show, NULL),
+	__ATTR(state, 0444, regulator_state_show, NULL),
+	__ATTR(min_microvolts, 0444, regulator_min_uV_show, NULL),
+	__ATTR(min_microamps, 0444, regulator_min_uA_show, NULL),
+	__ATTR(max_microvolts, 0444, regulator_max_uV_show, NULL),
+	__ATTR(max_microamps, 0444, regulator_max_uA_show, NULL),
+	__ATTR(requested_microamps, 0444, regulator_total_uA_show, NULL),
+	__ATTR(num_users, 0444, regulator_num_users_show, NULL),
+	__ATTR(type, 0444, regulator_type_show, NULL),
+	__ATTR(suspend_mem_microvolts, 0444,
+		regulator_suspend_mem_uV_show, NULL),
+	__ATTR(suspend_disk_microvolts, 0444,
+		regulator_suspend_disk_uV_show, NULL),
+	__ATTR(suspend_standby_microvolts, 0444,
+		regulator_suspend_standby_uV_show, NULL),
+	__ATTR(suspend_mem_mode, 0444,
+		regulator_suspend_mem_mode_show, NULL),
+	__ATTR(suspend_disk_mode, 0444,
+		regulator_suspend_disk_mode_show, NULL),
+	__ATTR(suspend_standby_mode, 0444,
+		regulator_suspend_standby_mode_show, NULL),
+	__ATTR(suspend_mem_state, 0444,
+		regulator_suspend_mem_state_show, NULL),
+	__ATTR(suspend_disk_state, 0444,
+		regulator_suspend_disk_state_show, NULL),
+	__ATTR(suspend_standby_state, 0444,
+		regulator_suspend_standby_state_show, NULL),
+	__ATTR_NULL,
+};
+
+static void regulator_dev_release(struct device *dev)
+{
+	struct regulator_dev *rdev = dev_get_drvdata(dev);
+	kfree(rdev);
+}
+
+static struct class regulator_class = {
+	.name = "regulator",
+	.dev_release = regulator_dev_release,
+	.dev_attrs = regulator_dev_attrs,
+};
+
+/* Calculate the new optimum regulator operating mode based on the new total
+ * consumer load. All locks held by caller */
+static void drms_uA_update(struct regulator_dev *rdev)
+{
+	struct regulator *sibling;
+	int current_uA = 0, output_uV, input_uV, err;
+	unsigned int mode;
+
+	err = regulator_check_drms(rdev);
+	if (err < 0 || !rdev->desc->ops->get_optimum_mode ||
+	    !rdev->desc->ops->get_voltage || !rdev->desc->ops->set_mode);
+	return;
+
+	/* get output voltage */
+	output_uV = rdev->desc->ops->get_voltage(rdev);
+	if (output_uV <= 0)
+		return;
+
+	/* get input voltage */
+	if (rdev->supply && rdev->supply->desc->ops->get_voltage)
+		input_uV = rdev->supply->desc->ops->get_voltage(rdev->supply);
+	else
+		input_uV = rdev->constraints->input_uV;
+	if (input_uV <= 0)
+		return;
+
+	/* calc total requested load */
+	list_for_each_entry(sibling, &rdev->consumer_list, list)
+	    current_uA += sibling->uA_load;
+
+	/* 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_check_mode(rdev, mode);
+	if (err == 0)
+		rdev->desc->ops->set_mode(rdev, mode);
+}
+
+static int suspend_set_state(struct regulator_dev *rdev,
+	struct regulator_state *rstate)
+{
+	int ret = 0;
+
+	/* enable & disable are mandatory for suspend control */
+	if (!rdev->desc->ops->set_suspend_enable ||
+		!rdev->desc->ops->set_suspend_disable) {
+		printk(KERN_ERR "%s: no way to set suspend state\n",
+			__func__);
+		return -EINVAL;
+	}
+
+	if (rstate->enabled)
+		ret = rdev->desc->ops->set_suspend_enable(rdev);
+	else
+		ret = rdev->desc->ops->set_suspend_disable(rdev);
+	if (ret < 0) {
+		printk(KERN_ERR "%s: failed to enabled/disable\n", __func__);
+		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) {
+			printk(KERN_ERR "%s: failed to set voltage\n",
+				__func__);
+			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) {
+			printk(KERN_ERR "%s: failed to set mode\n", __func__);
+			return ret;
+		}
+	}
+	return ret;
+}
+
+/* locks held by caller */
+static int suspend_prepare(struct regulator_dev *rdev, suspend_state_t state)
+{
+	if (!rdev->constraints)
+		return -EINVAL;
+
+	switch (state) {
+	case PM_SUSPEND_STANDBY:
+		return suspend_set_state(rdev,
+			&rdev->constraints->state_standby);
+	case PM_SUSPEND_MEM:
+		return suspend_set_state(rdev,
+			&rdev->constraints->state_mem);
+	case PM_SUSPEND_MAX:
+		return suspend_set_state(rdev,
+			&rdev->constraints->state_disk);
+	default:
+		return -EINVAL;
+	}
+}
+
+static void print_constraints(struct regulator_dev *rdev)
+{
+	struct regulation_constraints *constraints = rdev->constraints;
+	char buf[80];
+	int count;
+
+	if (rdev->desc->type == REGULATOR_VOLTAGE) {
+		if (constraints->min_uV == constraints->max_uV)
+			count = sprintf(buf, "%d mV ",
+					constraints->min_uV / 1000);
+		else
+			count = sprintf(buf, "%d <--> %d mV ",
+					constraints->min_uV / 1000,
+					constraints->max_uV / 1000);
+	} else {
+		if (constraints->min_uA == constraints->max_uA)
+			count = sprintf(buf, "%d mA ",
+					constraints->min_uA / 1000);
+		else
+			count = sprintf(buf, "%d <--> %d mA ",
+					constraints->min_uA / 1000,
+					constraints->max_uA / 1000);
+	}
+	if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
+		count += sprintf(buf + count, "fast ");
+	if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
+		count += sprintf(buf + count, "normal ");
+	if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
+		count += sprintf(buf + count, "idle ");
+	if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
+		count += sprintf(buf + count, "standby");
+
+	printk(KERN_INFO "regulator: %s: %s\n", rdev->desc->name, buf);
+}
+
+/**
+ * set_machine_constraints - sets regulator constraints
+ * @regulator: 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,
+	struct regulation_constraints *constraints)
+{
+	int ret = 0;
+	const char *name;
+	struct regulator_ops *ops = rdev->desc->ops;
+
+	if (constraints->name)
+		name = constraints->name;
+	else if (rdev->desc->name)
+		name = rdev->desc->name;
+	else
+		name = "regulator";
+
+	rdev->constraints = constraints;
+
+	/* do we need to apply the constraint voltage */
+	if (rdev->constraints->apply_uV &&
+		rdev->constraints->min_uV == rdev->constraints->max_uV &&
+		ops->set_voltage) {
+		ret = ops->set_voltage(rdev,
+			rdev->constraints->min_uV, rdev->constraints->max_uV);
+			if (ret < 0) {
+				printk(KERN_ERR "%s: failed to apply %duV constraint to %s\n",
+				       __func__,
+				       rdev->constraints->min_uV, name);
+				rdev->constraints = NULL;
+				goto out;
+			}
+	}
+
+	/* are we enabled at boot time by firmware / bootloader */
+	if (rdev->constraints->boot_on)
+		rdev->use_count = 1;
+
+	/* do we need to setup our suspend state */
+	if (constraints->initial_state) {
+		ret = suspend_prepare(rdev, constraints->initial_state);
+		if (ret < 0) {
+			printk(KERN_ERR "%s: failed to set suspend state for %s\n",
+			       __func__, name);
+			rdev->constraints = NULL;
+			goto out;
+		}
+	}
+
+	/* if always_on is set then turn the regulator on if it's not
+	 * already on. */
+	if (constraints->always_on && ops->enable &&
+	    ((ops->is_enabled && !ops->is_enabled(rdev)) ||
+	     (!ops->is_enabled && !constraints->boot_on))) {
+		ret = ops->enable(rdev);
+		if (ret < 0) {
+			printk(KERN_ERR "%s: failed to enable %s\n",
+			       __func__, name);
+			rdev->constraints = NULL;
+			goto out;
+		}
+	}
+
+	print_constraints(rdev);
+out:
+	return ret;
+}
+
+/**
+ * set_supply - set regulator supply regulator
+ * @regulator: regulator name
+ * @supply: supply regulator name
+ *
+ * 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;
+
+	err = sysfs_create_link(&rdev->dev.kobj, &supply_rdev->dev.kobj,
+				"supply");
+	if (err) {
+		printk(KERN_ERR
+		       "%s: could not add device link %s err %d\n",
+		       __func__, supply_rdev->dev.kobj.name, err);
+		       goto out;
+	}
+	rdev->supply = supply_rdev;
+	list_add(&rdev->slist, &supply_rdev->supply_list);
+out:
+	return err;
+}
+
+/**
+ * set_consumer_device_supply: Bind a regulator to a symbolic supply
+ * @regulator: regulator source
+ * @dev:       device the 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,
+	struct device *consumer_dev, const char *supply)
+{
+	struct regulator_map *node;
+
+	if (supply == NULL)
+		return -EINVAL;
+
+	node = kmalloc(sizeof(struct regulator_map), GFP_KERNEL);
+	if (node == NULL)
+		return -ENOMEM;
+
+	node->regulator = rdev;
+	node->dev = consumer_dev;
+	node->supply = supply;
+
+	list_add(&node->list, &regulator_map_list);
+	return 0;
+}
+
+static void unset_consumer_device_supply(struct regulator_dev *rdev,
+	struct device *consumer_dev)
+{
+	struct regulator_map *node, *n;
+
+	list_for_each_entry_safe(node, n, &regulator_map_list, list) {
+		if (rdev == node->regulator &&
+			consumer_dev == node->dev) {
+			list_del(&node->list);
+			kfree(node);
+			return;
+		}
+	}
+}
+
+#define REG_STR_SIZE	32
+
+static struct regulator *create_regulator(struct regulator_dev *rdev,
+					  struct device *dev,
+					  const char *supply_name)
+{
+	struct regulator *regulator;
+	char buf[REG_STR_SIZE];
+	int err, size;
+
+	regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
+	if (regulator == NULL)
+		return NULL;
+
+	mutex_lock(&rdev->mutex);
+	regulator->rdev = rdev;
+	list_add(&regulator->list, &rdev->consumer_list);
+
+	if (dev) {
+		/* create a 'requested_microamps_name' sysfs entry */
+		size = scnprintf(buf, REG_STR_SIZE, "microamps_requested_%s",
+			supply_name);
+		if (size >= REG_STR_SIZE)
+			goto overflow_err;
+
+		regulator->dev = dev;
+		regulator->dev_attr.attr.name = kstrdup(buf, GFP_KERNEL);
+		if (regulator->dev_attr.attr.name == NULL)
+			goto attr_name_err;
+
+		regulator->dev_attr.attr.owner = THIS_MODULE;
+		regulator->dev_attr.attr.mode = 0444;
+		regulator->dev_attr.show = device_requested_uA_show;
+		err = device_create_file(dev, &regulator->dev_attr);
+		if (err < 0) {
+			printk(KERN_WARNING "%s: could not add regulator_dev"
+				" load sysfs\n", __func__);
+			goto attr_name_err;
+		}
+
+		/* also add a link to the device sysfs entry */
+		size = scnprintf(buf, REG_STR_SIZE, "%s-%s",
+				 dev->kobj.name, supply_name);
+		if (size >= REG_STR_SIZE)
+			goto attr_err;
+
+		regulator->supply_name = kstrdup(buf, GFP_KERNEL);
+		if (regulator->supply_name == NULL)
+			goto attr_err;
+
+		err = sysfs_create_link(&rdev->dev.kobj, &dev->kobj,
+					buf);
+		if (err) {
+			printk(KERN_WARNING
+			       "%s: could not add device link %s err %d\n",
+			       __func__, dev->kobj.name, err);
+			device_remove_file(dev, &regulator->dev_attr);
+			goto link_name_err;
+		}
+	}
+	mutex_unlock(&rdev->mutex);
+	return regulator;
+link_name_err:
+	kfree(regulator->supply_name);
+attr_err:
+	device_remove_file(regulator->dev, &regulator->dev_attr);
+attr_name_err:
+	kfree(regulator->dev_attr.attr.name);
+overflow_err:
+	list_del(&regulator->list);
+	kfree(regulator);
+	mutex_unlock(&rdev->mutex);
+	return NULL;
+}
+
+/**
+ * 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.
+ */
+struct regulator *regulator_get(struct device *dev, const char *id)
+{
+	struct regulator_dev *rdev;
+	struct regulator_map *map;
+	struct regulator *regulator = ERR_PTR(-ENODEV);
+
+	if (id == NULL) {
+		printk(KERN_ERR "regulator: get() with no identifier\n");
+		return regulator;
+	}
+
+	mutex_lock(&regulator_list_mutex);
+
+	list_for_each_entry(map, &regulator_map_list, list) {
+		if (dev == map->dev &&
+		    strcmp(map->supply, id) == 0) {
+			rdev = map->regulator;
+			goto found;
+		}
+	}
+	printk(KERN_ERR "regulator: Unable to get requested regulator: %s\n",
+	       id);
+	mutex_unlock(&regulator_list_mutex);
+	return regulator;
+
+found:
+	if (!try_module_get(rdev->owner))
+		goto out;
+
+	regulator = create_regulator(rdev, dev, id);
+	if (regulator == NULL) {
+		regulator = ERR_PTR(-ENOMEM);
+		module_put(rdev->owner);
+	}
+
+out:
+	mutex_unlock(&regulator_list_mutex);
+	return regulator;
+}
+EXPORT_SYMBOL_GPL(regulator_get);
+
+/**
+ * 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)
+{
+	struct regulator_dev *rdev;
+
+	if (regulator == NULL || IS_ERR(regulator))
+		return;
+
+	if (regulator->enabled) {
+		printk(KERN_WARNING "Releasing supply %s while enabled\n",
+		       regulator->supply_name);
+		WARN_ON(regulator->enabled);
+		regulator_disable(regulator);
+	}
+
+	mutex_lock(&regulator_list_mutex);
+	rdev = regulator->rdev;
+
+	/* remove any sysfs entries */
+	if (regulator->dev) {
+		sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
+		kfree(regulator->supply_name);
+		device_remove_file(regulator->dev, &regulator->dev_attr);
+		kfree(regulator->dev_attr.attr.name);
+	}
+	list_del(&regulator->list);
+	kfree(regulator);
+
+	module_put(rdev->owner);
+	mutex_unlock(&regulator_list_mutex);
+}
+EXPORT_SYMBOL_GPL(regulator_put);
+
+/* locks held by regulator_enable() */
+static int _regulator_enable(struct regulator_dev *rdev)
+{
+	int ret = -EINVAL;
+
+	if (!rdev->constraints) {
+		printk(KERN_ERR "%s: %s has no constraints\n",
+		       __func__, rdev->desc->name);
+		return ret;
+	}
+
+	/* do we need to enable the supply regulator first */
+	if (rdev->supply) {
+		ret = _regulator_enable(rdev->supply);
+		if (ret < 0) {
+			printk(KERN_ERR "%s: failed to enable %s: %d\n",
+			       __func__, rdev->desc->name, ret);
+			return ret;
+		}
+	}
+
+	/* check voltage and requested load before enabling */
+	if (rdev->desc->ops->enable) {
+
+		if (rdev->constraints &&
+			(rdev->constraints->valid_ops_mask &
+			REGULATOR_CHANGE_DRMS))
+			drms_uA_update(rdev);
+
+		ret = rdev->desc->ops->enable(rdev);
+		if (ret < 0) {
+			printk(KERN_ERR "%s: failed to enable %s: %d\n",
+			       __func__, rdev->desc->name, ret);
+			return ret;
+		}
+		rdev->use_count++;
+		return ret;
+	}
+
+	return ret;
+}
+
+/**
+ * regulator_enable - enable regulator output
+ * @regulator: regulator source
+ *
+ * Enable the regulator output at the predefined voltage or current value.
+ * NOTE: the output value can be set by other drivers, boot loader or may be
+ * hardwired in the regulator.
+ * NOTE: calls to regulator_enable() must be balanced with calls to
+ * regulator_disable().
+ */
+int regulator_enable(struct regulator *regulator)
+{
+	int ret;
+
+	if (regulator->enabled) {
+		printk(KERN_CRIT "Regulator %s already enabled\n",
+		       regulator->supply_name);
+		WARN_ON(regulator->enabled);
+		return 0;
+	}
+
+	mutex_lock(&regulator->rdev->mutex);
+	regulator->enabled = 1;
+	ret = _regulator_enable(regulator->rdev);
+	if (ret != 0)
+		regulator->enabled = 0;
+	mutex_unlock(&regulator->rdev->mutex);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_enable);
+
+/* locks held by regulator_disable() */
+static int _regulator_disable(struct regulator_dev *rdev)
+{
+	int ret = 0;
+
+	/* are we the last user and permitted to disable ? */
+	if (rdev->use_count == 1 && !rdev->constraints->always_on) {
+
+		/* we are last user */
+		if (rdev->desc->ops->disable) {
+			ret = rdev->desc->ops->disable(rdev);
+			if (ret < 0) {
+				printk(KERN_ERR "%s: failed to disable %s\n",
+				       __func__, rdev->desc->name);
+				return ret;
+			}
+		}
+
+		/* decrease our supplies ref count and disable if required */
+		if (rdev->supply)
+			_regulator_disable(rdev->supply);
+
+		rdev->use_count = 0;
+	} else if (rdev->use_count > 1) {
+
+		if (rdev->constraints &&
+			(rdev->constraints->valid_ops_mask &
+			REGULATOR_CHANGE_DRMS))
+			drms_uA_update(rdev);
+
+		rdev->use_count--;
+	}
+	return ret;
+}
+
+/**
+ * regulator_disable - disable regulator output
+ * @regulator: regulator source
+ *
+ * Disable the regulator output voltage or current.
+ * NOTE: this will only disable the regulator output if no other consumer
+ * devices have it enabled.
+ * NOTE: calls to regulator_enable() must be balanced with calls to
+ * regulator_disable().
+ */
+int regulator_disable(struct regulator *regulator)
+{
+	int ret;
+
+	if (!regulator->enabled) {
+		printk(KERN_ERR "%s: not in use by this consumer\n",
+			__func__);
+		return 0;
+	}
+
+	mutex_lock(&regulator->rdev->mutex);
+	regulator->enabled = 0;
+	regulator->uA_load = 0;
+	ret = _regulator_disable(regulator->rdev);
+	mutex_unlock(&regulator->rdev->mutex);
+	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;
+
+	/* force disable */
+	if (rdev->desc->ops->disable) {
+		/* ah well, who wants to live forever... */
+		ret = rdev->desc->ops->disable(rdev);
+		if (ret < 0) {
+			printk(KERN_ERR "%s: failed to force disable %s\n",
+			       __func__, rdev->desc->name);
+			return ret;
+		}
+		/* notify other consumers that power has been forced off */
+		_notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE,
+			NULL);
+	}
+
+	/* decrease our supplies ref count and disable if required */
+	if (rdev->supply)
+		_regulator_disable(rdev->supply);
+
+	rdev->use_count = 0;
+	return ret;
+}
+
+/**
+ * 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)
+{
+	int ret;
+
+	mutex_lock(&regulator->rdev->mutex);
+	regulator->enabled = 0;
+	regulator->uA_load = 0;
+	ret = _regulator_force_disable(regulator->rdev);
+	mutex_unlock(&regulator->rdev->mutex);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_force_disable);
+
+static int _regulator_is_enabled(struct regulator_dev *rdev)
+{
+	int ret;
+
+	mutex_lock(&rdev->mutex);
+
+	/* sanity check */
+	if (!rdev->desc->ops->is_enabled) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	ret = rdev->desc->ops->is_enabled(rdev);
+out:
+	mutex_unlock(&rdev->mutex);
+	return ret;
+}
+
+/**
+ * regulator_is_enabled - is the regulator output enabled
+ * @regulator: regulator source
+ *
+ * Returns zero for disabled otherwise return number of enable requests.
+ */
+int regulator_is_enabled(struct regulator *regulator)
+{
+	return _regulator_is_enabled(regulator->rdev);
+}
+EXPORT_SYMBOL_GPL(regulator_is_enabled);
+
+/**
+ * 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.
+ * NOTE: 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 regulator_dev *rdev = regulator->rdev;
+	int ret;
+
+	mutex_lock(&rdev->mutex);
+
+	/* sanity check */
+	if (!rdev->desc->ops->set_voltage) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	/* constraints check */
+	ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
+	if (ret < 0)
+		goto out;
+	regulator->min_uV = min_uV;
+	regulator->max_uV = max_uV;
+	ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV);
+
+out:
+	mutex_unlock(&rdev->mutex);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_set_voltage);
+
+static int _regulator_get_voltage(struct regulator_dev *rdev)
+{
+	/* sanity check */
+	if (rdev->desc->ops->get_voltage)
+		return rdev->desc->ops->get_voltage(rdev);
+	else
+		return -EINVAL;
+}
+
+/**
+ * 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)
+{
+	int ret;
+
+	mutex_lock(&regulator->rdev->mutex);
+
+	ret = _regulator_get_voltage(regulator->rdev);
+
+	mutex_unlock(&regulator->rdev->mutex);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_get_voltage);
+
+/**
+ * regulator_set_current_limit - set regulator output current limit
+ * @regulator: regulator source
+ * @min_uA: Minimuum 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;
+
+	mutex_lock(&rdev->mutex);
+
+	/* 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:
+	mutex_unlock(&rdev->mutex);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_set_current_limit);
+
+static int _regulator_get_current_limit(struct regulator_dev *rdev)
+{
+	int ret;
+
+	mutex_lock(&rdev->mutex);
+
+	/* sanity check */
+	if (!rdev->desc->ops->get_current_limit) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	ret = rdev->desc->ops->get_current_limit(rdev);
+out:
+	mutex_unlock(&rdev->mutex);
+	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;
+
+	mutex_lock(&rdev->mutex);
+
+	/* sanity check */
+	if (!rdev->desc->ops->set_mode) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	/* constraints check */
+	ret = regulator_check_mode(rdev, mode);
+	if (ret < 0)
+		goto out;
+
+	ret = rdev->desc->ops->set_mode(rdev, mode);
+out:
+	mutex_unlock(&rdev->mutex);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_set_mode);
+
+static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
+{
+	int ret;
+
+	mutex_lock(&rdev->mutex);
+
+	/* sanity check */
+	if (!rdev->desc->ops->get_mode) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	ret = rdev->desc->ops->get_mode(rdev);
+out:
+	mutex_unlock(&rdev->mutex);
+	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);
+
+/**
+ * regulator_set_optimum_mode - set regulator optimum operating mode
+ * @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.
+ *
+ * Returns the new regulator mode or error.
+ */
+int regulator_set_optimum_mode(struct regulator *regulator, int uA_load)
+{
+	struct regulator_dev *rdev = regulator->rdev;
+	struct regulator *consumer;
+	int ret, output_uV, input_uV, total_uA_load = 0;
+	unsigned int mode;
+
+	mutex_lock(&rdev->mutex);
+
+	regulator->uA_load = uA_load;
+	ret = regulator_check_drms(rdev);
+	if (ret < 0)
+		goto out;
+	ret = -EINVAL;
+
+	/* sanity check */
+	if (!rdev->desc->ops->get_optimum_mode)
+		goto out;
+
+	/* get output voltage */
+	output_uV = rdev->desc->ops->get_voltage(rdev);
+	if (output_uV <= 0) {
+		printk(KERN_ERR "%s: invalid output voltage found for %s\n",
+			__func__, rdev->desc->name);
+		goto out;
+	}
+
+	/* get input voltage */
+	if (rdev->supply && rdev->supply->desc->ops->get_voltage)
+		input_uV = rdev->supply->desc->ops->get_voltage(rdev->supply);
+	else
+		input_uV = rdev->constraints->input_uV;
+	if (input_uV <= 0) {
+		printk(KERN_ERR "%s: invalid input voltage found for %s\n",
+			__func__, rdev->desc->name);
+		goto out;
+	}
+
+	/* calc total requested load for this regulator */
+	list_for_each_entry(consumer, &rdev->consumer_list, list)
+	    total_uA_load += consumer->uA_load;
+
+	mode = rdev->desc->ops->get_optimum_mode(rdev,
+						 input_uV, output_uV,
+						 total_uA_load);
+	if (ret <= 0) {
+		printk(KERN_ERR "%s: failed to get optimum mode for %s @"
+			" %d uA %d -> %d uV\n", __func__, rdev->desc->name,
+			total_uA_load, input_uV, output_uV);
+		goto out;
+	}
+
+	ret = rdev->desc->ops->set_mode(rdev, mode);
+	if (ret <= 0) {
+		printk(KERN_ERR "%s: failed to set optimum mode %x for %s\n",
+			__func__, mode, rdev->desc->name);
+		goto out;
+	}
+	ret = mode;
+out:
+	mutex_unlock(&rdev->mutex);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_set_optimum_mode);
+
+/**
+ * regulator_register_notifier - register regulator event notifier
+ * @regulator: regulator source
+ * @notifier_block: 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
+ * @notifier_block: 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 */
+static void _notifier_call_chain(struct regulator_dev *rdev,
+				  unsigned long event, void *data)
+{
+	struct regulator_dev *_rdev;
+
+	/* call rdev chain first */
+	mutex_lock(&rdev->mutex);
+	blocking_notifier_call_chain(&rdev->notifier, event, NULL);
+	mutex_unlock(&rdev->mutex);
+
+	/* now notify regulator we supply */
+	list_for_each_entry(_rdev, &rdev->supply_list, slist)
+		_notifier_call_chain(_rdev, 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)) {
+			dev_err(dev, "Failed to get supply '%s'\n",
+				consumers[i].supply);
+			ret = PTR_ERR(consumers[i].consumer);
+			consumers[i].consumer = NULL;
+			goto err;
+		}
+	}
+
+	return 0;
+
+err:
+	for (i = 0; i < num_consumers && consumers[i].consumer; i++)
+		regulator_put(consumers[i].consumer);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_bulk_get);
+
+/**
+ * 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)
+{
+	int i;
+	int ret;
+
+	for (i = 0; i < num_consumers; i++) {
+		ret = regulator_enable(consumers[i].consumer);
+		if (ret != 0)
+			goto err;
+	}
+
+	return 0;
+
+err:
+	printk(KERN_ERR "Failed to enable %s\n", consumers[i].supply);
+	for (i = 0; i < num_consumers; i++)
+		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 enabled
+ * then any others that were disabled will be disabled again prior to
+ * return.
+ */
+int regulator_bulk_disable(int num_consumers,
+			   struct regulator_bulk_data *consumers)
+{
+	int i;
+	int ret;
+
+	for (i = 0; i < num_consumers; i++) {
+		ret = regulator_disable(consumers[i].consumer);
+		if (ret != 0)
+			goto err;
+	}
+
+	return 0;
+
+err:
+	printk(KERN_ERR "Failed to disable %s\n", consumers[i].supply);
+	for (i = 0; i < num_consumers; i++)
+		regulator_enable(consumers[i].consumer);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_bulk_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
+ * @regulator: regulator source
+ * @event: notifier block
+ * @data:
+ *
+ * Called by regulator drivers to notify clients a regulator event has
+ * occurred. We also notify regulator clients downstream.
+ */
+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_register - register regulator
+ * @regulator: regulator source
+ * @reg_data: private regulator data
+ *
+ * Called by regulator drivers to register a regulator.
+ * Returns 0 on success.
+ */
+struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc,
+	struct device *dev, void *driver_data)
+{
+	static atomic_t regulator_no = ATOMIC_INIT(0);
+	struct regulator_dev *rdev;
+	struct regulator_init_data *init_data = dev->platform_data;
+	int ret, i;
+
+	if (regulator_desc == NULL)
+		return ERR_PTR(-EINVAL);
+
+	if (regulator_desc->name == NULL || regulator_desc->ops == NULL)
+		return ERR_PTR(-EINVAL);
+
+	if (!regulator_desc->type == REGULATOR_VOLTAGE &&
+	    !regulator_desc->type == REGULATOR_CURRENT)
+		return ERR_PTR(-EINVAL);
+
+	if (!init_data)
+		return ERR_PTR(-EINVAL);
+
+	rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
+	if (rdev == NULL)
+		return ERR_PTR(-ENOMEM);
+
+	mutex_lock(&regulator_list_mutex);
+
+	mutex_init(&rdev->mutex);
+	rdev->reg_data = driver_data;
+	rdev->owner = regulator_desc->owner;
+	rdev->desc = regulator_desc;
+	INIT_LIST_HEAD(&rdev->consumer_list);
+	INIT_LIST_HEAD(&rdev->supply_list);
+	INIT_LIST_HEAD(&rdev->list);
+	INIT_LIST_HEAD(&rdev->slist);
+	BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
+
+	/* preform any regulator specific init */
+	if (init_data->regulator_init) {
+		ret = init_data->regulator_init(rdev->reg_data);
+		if (ret < 0) {
+			kfree(rdev);
+			rdev = ERR_PTR(ret);
+			goto out;
+		}
+	}
+
+	/* set regulator constraints */
+	ret = set_machine_constraints(rdev, &init_data->constraints);
+	if (ret < 0) {
+		kfree(rdev);
+		rdev = ERR_PTR(ret);
+		goto out;
+	}
+
+	/* register with sysfs */
+	rdev->dev.class = &regulator_class;
+	rdev->dev.parent = dev;
+	snprintf(rdev->dev.bus_id, sizeof(rdev->dev.bus_id),
+		 "regulator.%d", atomic_inc_return(&regulator_no) - 1);
+	ret = device_register(&rdev->dev);
+	if (ret != 0) {
+		kfree(rdev);
+		rdev = ERR_PTR(ret);
+		goto out;
+	}
+
+	dev_set_drvdata(&rdev->dev, rdev);
+
+	/* set supply regulator if it exists */
+	if (init_data->supply_regulator_dev) {
+		ret = set_supply(rdev,
+			dev_get_drvdata(init_data->supply_regulator_dev));
+		if (ret < 0) {
+			device_unregister(&rdev->dev);
+			kfree(rdev);
+			rdev = ERR_PTR(ret);
+			goto out;
+		}
+	}
+
+	/* add consumers devices */
+	for (i = 0; i < init_data->num_consumer_supplies; i++) {
+		ret = set_consumer_device_supply(rdev,
+			init_data->consumer_supplies[i].dev,
+			init_data->consumer_supplies[i].supply);
+		if (ret < 0) {
+			for (--i; i >= 0; i--)
+				unset_consumer_device_supply(rdev,
+					init_data->consumer_supplies[i].dev);
+			device_unregister(&rdev->dev);
+			kfree(rdev);
+			rdev = ERR_PTR(ret);
+			goto out;
+		}
+	}
+
+	list_add(&rdev->list, &regulator_list);
+out:
+	mutex_unlock(&regulator_list_mutex);
+	return rdev;
+}
+EXPORT_SYMBOL_GPL(regulator_register);
+
+/**
+ * regulator_unregister - unregister regulator
+ * @regulator: regulator source
+ *
+ * Called by regulator drivers to unregister a regulator.
+ */
+void regulator_unregister(struct regulator_dev *rdev)
+{
+	if (rdev == NULL)
+		return;
+
+	mutex_lock(&regulator_list_mutex);
+	list_del(&rdev->list);
+	if (rdev->supply)
+		sysfs_remove_link(&rdev->dev.kobj, "supply");
+	device_unregister(&rdev->dev);
+	mutex_unlock(&regulator_list_mutex);
+}
+EXPORT_SYMBOL_GPL(regulator_unregister);
+
+/**
+ * regulator_suspend_prepare: prepare regulators for system wide suspend
+ * @state: system suspend state
+ *
+ * Configure each regulator with it's suspend operating parameters for state.
+ * This will usually be called by machine suspend code prior to supending.
+ */
+int regulator_suspend_prepare(suspend_state_t state)
+{
+	struct regulator_dev *rdev;
+	int ret = 0;
+
+	/* ON is handled by regulator active state */
+	if (state == PM_SUSPEND_ON)
+		return -EINVAL;
+
+	mutex_lock(&regulator_list_mutex);
+	list_for_each_entry(rdev, &regulator_list, list) {
+
+		mutex_lock(&rdev->mutex);
+		ret = suspend_prepare(rdev, state);
+		mutex_unlock(&rdev->mutex);
+
+		if (ret < 0) {
+			printk(KERN_ERR "%s: failed to prepare %s\n",
+				__func__, rdev->desc->name);
+			goto out;
+		}
+	}
+out:
+	mutex_unlock(&regulator_list_mutex);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_suspend_prepare);
+
+/**
+ * rdev_get_drvdata - get rdev regulator driver data
+ * @regulator: 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
+ * @regulator: 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);
+
+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);
+
+static int __init regulator_init(void)
+{
+	printk(KERN_INFO "regulator: core version %s\n", REGULATOR_VERSION);
+	return class_register(&regulator_class);
+}
+
+/* init early to allow our consumers to complete system booting */
+core_initcall(regulator_init);