7 files changed, 529 insertions, 4 deletions
diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 67d47b59a66..f73d6f5ce6d 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -450,5 +450,12 @@ config REGULATOR_WM8994
 	  This driver provides support for the voltage regulators on the
 	  WM8994 CODEC.
 
+config REGULATOR_AS3711
+	tristate "AS3711 PMIC"
+	depends on MFD_AS3711
+	help
+	  This driver provides support for the voltage regulators on the
+	  AS3711 PMIC
+
 endif
 
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index e431eed8a87..c1557ace909 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -16,6 +16,7 @@ obj-$(CONFIG_REGULATOR_AB8500)	+= ab8500.o
 obj-$(CONFIG_REGULATOR_AD5398) += ad5398.o
 obj-$(CONFIG_REGULATOR_ANATOP) += anatop-regulator.o
 obj-$(CONFIG_REGULATOR_ARIZONA) += arizona-micsupp.o arizona-ldo1.o
+obj-$(CONFIG_REGULATOR_AS3711) += as3711-regulator.o
 obj-$(CONFIG_REGULATOR_DA903X)	+= da903x.o
 obj-$(CONFIG_REGULATOR_DA9052)	+= da9052-regulator.o
 obj-$(CONFIG_REGULATOR_DBX500_PRCMU) += dbx500-prcmu.o
diff --git a/drivers/regulator/arizona-ldo1.c b/drivers/regulator/arizona-ldo1.c
index d184aa35abc..739faf99b9e 100644
--- a/drivers/regulator/arizona-ldo1.c
+++ b/drivers/regulator/arizona-ldo1.c
@@ -34,6 +34,108 @@ struct arizona_ldo1 {
 	struct regulator_init_data init_data;
 };
 
+static int arizona_ldo1_hc_list_voltage(struct regulator_dev *rdev,
+					unsigned int selector)
+{
+	if (selector >= rdev->desc->n_voltages)
+		return -EINVAL;
+
+	if (selector == rdev->desc->n_voltages - 1)
+		return 1800000;
+	else
+		return rdev->desc->min_uV + (rdev->desc->uV_step * selector);
+}
+
+static int arizona_ldo1_hc_map_voltage(struct regulator_dev *rdev,
+				       int min_uV, int max_uV)
+{
+	int sel;
+
+	sel = DIV_ROUND_UP(min_uV - rdev->desc->min_uV, rdev->desc->uV_step);
+	if (sel >= rdev->desc->n_voltages)
+		sel = rdev->desc->n_voltages - 1;
+
+	return sel;
+}
+
+static int arizona_ldo1_hc_set_voltage_sel(struct regulator_dev *rdev,
+					   unsigned sel)
+{
+	struct arizona_ldo1 *ldo = rdev_get_drvdata(rdev);
+	struct regmap *regmap = ldo->arizona->regmap;
+	unsigned int val;
+	int ret;
+
+	if (sel == rdev->desc->n_voltages - 1)
+		val = ARIZONA_LDO1_HI_PWR;
+	else
+		val = 0;
+
+	ret = regmap_update_bits(regmap, ARIZONA_LDO1_CONTROL_2,
+				 ARIZONA_LDO1_HI_PWR, val);
+	if (ret != 0)
+		return ret;
+
+	ret = regmap_update_bits(regmap, ARIZONA_DYNAMIC_FREQUENCY_SCALING_1,
+				 ARIZONA_SUBSYS_MAX_FREQ, val);
+	if (ret != 0)
+		return ret;
+
+	if (val)
+		return 0;
+
+	val = sel << ARIZONA_LDO1_VSEL_SHIFT;
+
+	return regmap_update_bits(regmap, ARIZONA_LDO1_CONTROL_1,
+				  ARIZONA_LDO1_VSEL_MASK, val);
+}
+
+static int arizona_ldo1_hc_get_voltage_sel(struct regulator_dev *rdev)
+{
+	struct arizona_ldo1 *ldo = rdev_get_drvdata(rdev);
+	struct regmap *regmap = ldo->arizona->regmap;
+	unsigned int val;
+	int ret;
+
+	ret = regmap_read(regmap, ARIZONA_LDO1_CONTROL_2, &val);
+	if (ret != 0)
+		return ret;
+
+	if (val & ARIZONA_LDO1_HI_PWR)
+		return rdev->desc->n_voltages - 1;
+
+	ret = regmap_read(regmap, ARIZONA_LDO1_CONTROL_1, &val);
+	if (ret != 0)
+		return ret;
+
+	return (val & ARIZONA_LDO1_VSEL_MASK) >> ARIZONA_LDO1_VSEL_SHIFT;
+}
+
+static struct regulator_ops arizona_ldo1_hc_ops = {
+	.list_voltage = arizona_ldo1_hc_list_voltage,
+	.map_voltage = arizona_ldo1_hc_map_voltage,
+	.get_voltage_sel = arizona_ldo1_hc_get_voltage_sel,
+	.set_voltage_sel = arizona_ldo1_hc_set_voltage_sel,
+	.get_bypass = regulator_get_bypass_regmap,
+	.set_bypass = regulator_set_bypass_regmap,
+};
+
+static const struct regulator_desc arizona_ldo1_hc = {
+	.name = "LDO1",
+	.supply_name = "LDOVDD",
+	.type = REGULATOR_VOLTAGE,
+	.ops = &arizona_ldo1_hc_ops,
+
+	.bypass_reg = ARIZONA_LDO1_CONTROL_1,
+	.bypass_mask = ARIZONA_LDO1_BYPASS,
+	.min_uV = 900000,
+	.uV_step = 50000,
+	.n_voltages = 8,
+	.enable_time = 500,
+
+	.owner = THIS_MODULE,
+};
+
 static struct regulator_ops arizona_ldo1_ops = {
 	.list_voltage = regulator_list_voltage_linear,
 	.map_voltage = regulator_map_voltage_linear,
@@ -55,11 +157,22 @@ static const struct regulator_desc arizona_ldo1 = {
 	.bypass_mask = ARIZONA_LDO1_BYPASS,
 	.min_uV = 900000,
 	.uV_step = 50000,
-	.n_voltages = 6,
+	.n_voltages = 7,
+	.enable_time = 500,
 
 	.owner = THIS_MODULE,
 };
 
+static const struct regulator_init_data arizona_ldo1_dvfs = {
+	.constraints = {
+		.min_uV = 1200000,
+		.max_uV = 1800000,
+		.valid_ops_mask = REGULATOR_CHANGE_STATUS |
+				  REGULATOR_CHANGE_VOLTAGE,
+	},
+	.num_consumer_supplies = 1,
+};
+
 static const struct regulator_init_data arizona_ldo1_default = {
 	.constraints = {
 		.valid_ops_mask = REGULATOR_CHANGE_STATUS,
@@ -70,6 +183,7 @@ static const struct regulator_init_data arizona_ldo1_default = {
 static __devinit int arizona_ldo1_probe(struct platform_device *pdev)
 {
 	struct arizona *arizona = dev_get_drvdata(pdev->dev.parent);
+	const struct regulator_desc *desc;
 	struct regulator_config config = { };
 	struct arizona_ldo1 *ldo1;
 	int ret;
@@ -87,7 +201,17 @@ static __devinit int arizona_ldo1_probe(struct platform_device *pdev)
 	 * default init_data for it.  This will be overridden with
 	 * platform data if provided.
 	 */
-	ldo1->init_data = arizona_ldo1_default;
+	switch (arizona->type) {
+	case WM5102:
+		desc = &arizona_ldo1_hc;
+		ldo1->init_data = arizona_ldo1_dvfs;
+		break;
+	default:
+		desc = &arizona_ldo1;
+		ldo1->init_data = arizona_ldo1_default;
+		break;
+	}
+
 	ldo1->init_data.consumer_supplies = &ldo1->supply;
 	ldo1->supply.supply = "DCVDD";
 	ldo1->supply.dev_name = dev_name(arizona->dev);
@@ -102,7 +226,7 @@ static __devinit int arizona_ldo1_probe(struct platform_device *pdev)
 	else
 		config.init_data = &ldo1->init_data;
 
-	ldo1->regulator = regulator_register(&arizona_ldo1, &config);
+	ldo1->regulator = regulator_register(desc, &config);
 	if (IS_ERR(ldo1->regulator)) {
 		ret = PTR_ERR(ldo1->regulator);
 		dev_err(arizona->dev, "Failed to register LDO1 supply: %d\n",
diff --git a/drivers/regulator/arizona-micsupp.c b/drivers/regulator/arizona-micsupp.c
index d9b1f82cc5b..93d0604e64b 100644
--- a/drivers/regulator/arizona-micsupp.c
+++ b/drivers/regulator/arizona-micsupp.c
@@ -101,6 +101,8 @@ static const struct regulator_desc arizona_micsupp = {
 	.bypass_reg = ARIZONA_MIC_CHARGE_PUMP_1,
 	.bypass_mask = ARIZONA_CPMIC_BYPASS,
 
+	.enable_time = 3000,
+
 	.owner = THIS_MODULE,
 };
 
diff --git a/drivers/regulator/as3711-regulator.c b/drivers/regulator/as3711-regulator.c
new file mode 100644
index 00000000000..2f1341db38a
--- /dev/null
+++ b/drivers/regulator/as3711-regulator.c
@@ -0,0 +1,369 @@
+/*
+ * AS3711 PMIC regulator driver, using DCDC Step Down and LDO supplies
+ *
+ * Copyright (C) 2012 Renesas Electronics Corporation
+ * Author: Guennadi Liakhovetski, <g.liakhovetski@gmx.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the version 2 of the GNU General Public License as
+ * published by the Free Software Foundation
+ */
+
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/mfd/as3711.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/regulator/driver.h>
+#include <linux/slab.h>
+
+struct as3711_regulator_info {
+	struct regulator_desc	desc;
+	unsigned int		max_uV;
+};
+
+struct as3711_regulator {
+	struct as3711_regulator_info *reg_info;
+	struct regulator_dev *rdev;
+};
+
+static int as3711_list_voltage_sd(struct regulator_dev *rdev,
+				  unsigned int selector)
+{
+	if (selector >= rdev->desc->n_voltages)
+		return -EINVAL;
+
+	if (!selector)
+		return 0;
+	if (selector < 0x41)
+		return 600000 + selector * 12500;
+	if (selector < 0x71)
+		return 1400000 + (selector - 0x40) * 25000;
+	return 2600000 + (selector - 0x70) * 50000;
+}
+
+static int as3711_list_voltage_aldo(struct regulator_dev *rdev,
+				    unsigned int selector)
+{
+	if (selector >= rdev->desc->n_voltages)
+		return -EINVAL;
+
+	if (selector < 0x10)
+		return 1200000 + selector * 50000;
+	return 1800000 + (selector - 0x10) * 100000;
+}
+
+static int as3711_list_voltage_dldo(struct regulator_dev *rdev,
+				    unsigned int selector)
+{
+	if (selector >= rdev->desc->n_voltages ||
+	    (selector > 0x10 && selector < 0x20))
+		return -EINVAL;
+
+	if (selector < 0x11)
+		return 900000 + selector * 50000;
+	return 1750000 + (selector - 0x20) * 50000;
+}
+
+static int as3711_bound_check(struct regulator_dev *rdev,
+			      int *min_uV, int *max_uV)
+{
+	struct as3711_regulator *reg = rdev_get_drvdata(rdev);
+	struct as3711_regulator_info *info = reg->reg_info;
+
+	dev_dbg(&rdev->dev, "%s(), %d, %d, %d\n", __func__,
+		*min_uV, rdev->desc->min_uV, info->max_uV);
+
+	if (*max_uV < *min_uV ||
+	    *min_uV > info->max_uV || rdev->desc->min_uV > *max_uV)
+		return -EINVAL;
+
+	if (rdev->desc->n_voltages == 1)
+		return 0;
+
+	if (*max_uV > info->max_uV)
+		*max_uV = info->max_uV;
+
+	if (*min_uV < rdev->desc->min_uV)
+		*min_uV = rdev->desc->min_uV;
+
+	return *min_uV;
+}
+
+static int as3711_sel_check(int min, int max, int bottom, int step)
+{
+	int sel, voltage;
+
+	/* Round up min, when dividing: keeps us within the range */
+	sel = DIV_ROUND_UP(min - bottom, step);
+	voltage = sel * step + bottom;
+	pr_debug("%s(): select %d..%d in %d+N*%d: %d\n", __func__,
+	       min, max, bottom, step, sel);
+	if (voltage > max)
+		return -EINVAL;
+
+	return sel;
+}
+
+static int as3711_map_voltage_sd(struct regulator_dev *rdev,
+				 int min_uV, int max_uV)
+{
+	int ret;
+
+	ret = as3711_bound_check(rdev, &min_uV, &max_uV);
+	if (ret <= 0)
+		return ret;
+
+	if (min_uV <= 1400000)
+		return as3711_sel_check(min_uV, max_uV, 600000, 12500);
+
+	if (min_uV <= 2600000)
+		return as3711_sel_check(min_uV, max_uV, 1400000, 25000) + 0x40;
+
+	return as3711_sel_check(min_uV, max_uV, 2600000, 50000) + 0x70;
+}
+
+/*
+ * The regulator API supports 4 modes of operataion: FAST, NORMAL, IDLE and
+ * STANDBY. We map them in the following way to AS3711 SD1-4 DCDC modes:
+ * FAST:	sdX_fast=1
+ * NORMAL:	low_noise=1
+ * IDLE:	low_noise=0
+ */
+
+static int as3711_set_mode_sd(struct regulator_dev *rdev, unsigned int mode)
+{
+	unsigned int fast_bit = rdev->desc->enable_mask,
+		low_noise_bit = fast_bit << 4;
+	u8 val;
+
+	switch (mode) {
+	case REGULATOR_MODE_FAST:
+		val = fast_bit | low_noise_bit;
+		break;
+	case REGULATOR_MODE_NORMAL:
+		val = low_noise_bit;
+		break;
+	case REGULATOR_MODE_IDLE:
+		val = 0;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return regmap_update_bits(rdev->regmap, AS3711_SD_CONTROL_1,
+				  low_noise_bit | fast_bit, val);
+}
+
+static unsigned int as3711_get_mode_sd(struct regulator_dev *rdev)
+{
+	unsigned int fast_bit = rdev->desc->enable_mask,
+		low_noise_bit = fast_bit << 4, mask = fast_bit | low_noise_bit;
+	unsigned int val;
+	int ret = regmap_read(rdev->regmap, AS3711_SD_CONTROL_1, &val);
+
+	if (ret < 0)
+		return ret;
+
+	if ((val & mask) == mask)
+		return REGULATOR_MODE_FAST;
+
+	if ((val & mask) == low_noise_bit)
+		return REGULATOR_MODE_NORMAL;
+
+	if (!(val & mask))
+		return REGULATOR_MODE_IDLE;
+
+	return -EINVAL;
+}
+
+static int as3711_map_voltage_aldo(struct regulator_dev *rdev,
+				  int min_uV, int max_uV)
+{
+	int ret;
+
+	ret = as3711_bound_check(rdev, &min_uV, &max_uV);
+	if (ret <= 0)
+		return ret;
+
+	if (min_uV <= 1800000)
+		return as3711_sel_check(min_uV, max_uV, 1200000, 50000);
+
+	return as3711_sel_check(min_uV, max_uV, 1800000, 100000) + 0x10;
+}
+
+static int as3711_map_voltage_dldo(struct regulator_dev *rdev,
+				  int min_uV, int max_uV)
+{
+	int ret;
+
+	ret = as3711_bound_check(rdev, &min_uV, &max_uV);
+	if (ret <= 0)
+		return ret;
+
+	if (min_uV <= 1700000)
+		return as3711_sel_check(min_uV, max_uV, 900000, 50000);
+
+	return as3711_sel_check(min_uV, max_uV, 1750000, 50000) + 0x20;
+}
+
+static struct regulator_ops as3711_sd_ops = {
+	.is_enabled		= regulator_is_enabled_regmap,
+	.enable			= regulator_enable_regmap,
+	.disable		= regulator_disable_regmap,
+	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
+	.set_voltage_sel	= regulator_set_voltage_sel_regmap,
+	.list_voltage		= as3711_list_voltage_sd,
+	.map_voltage		= as3711_map_voltage_sd,
+	.get_mode		= as3711_get_mode_sd,
+	.set_mode		= as3711_set_mode_sd,
+};
+
+static struct regulator_ops as3711_aldo_ops = {
+	.is_enabled		= regulator_is_enabled_regmap,
+	.enable			= regulator_enable_regmap,
+	.disable		= regulator_disable_regmap,
+	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
+	.set_voltage_sel	= regulator_set_voltage_sel_regmap,
+	.list_voltage		= as3711_list_voltage_aldo,
+	.map_voltage		= as3711_map_voltage_aldo,
+};
+
+static struct regulator_ops as3711_dldo_ops = {
+	.is_enabled		= regulator_is_enabled_regmap,
+	.enable			= regulator_enable_regmap,
+	.disable		= regulator_disable_regmap,
+	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
+	.set_voltage_sel	= regulator_set_voltage_sel_regmap,
+	.list_voltage		= as3711_list_voltage_dldo,
+	.map_voltage		= as3711_map_voltage_dldo,
+};
+
+#define AS3711_REG(_id, _en_reg, _en_bit, _vmask, _vshift, _min_uV, _max_uV, _sfx)	\
+	[AS3711_REGULATOR_ ## _id] = {							\
+	.desc = {									\
+		.name = "as3711-regulator-" # _id,					\
+		.id = AS3711_REGULATOR_ ## _id,						\
+		.n_voltages = (_vmask + 1),						\
+		.ops = &as3711_ ## _sfx ## _ops,					\
+		.type = REGULATOR_VOLTAGE,						\
+		.owner = THIS_MODULE,							\
+		.vsel_reg = AS3711_ ## _id ## _VOLTAGE,					\
+		.vsel_mask = _vmask << _vshift,						\
+		.enable_reg = AS3711_ ## _en_reg,					\
+		.enable_mask = BIT(_en_bit),						\
+		.min_uV	= _min_uV,							\
+	},										\
+	.max_uV = _max_uV,								\
+}
+
+static struct as3711_regulator_info as3711_reg_info[] = {
+	AS3711_REG(SD_1, SD_CONTROL, 0, 0x7f, 0, 612500, 3350000, sd),
+	AS3711_REG(SD_2, SD_CONTROL, 1, 0x7f, 0, 612500, 3350000, sd),
+	AS3711_REG(SD_3, SD_CONTROL, 2, 0x7f, 0, 612500, 3350000, sd),
+	AS3711_REG(SD_4, SD_CONTROL, 3, 0x7f, 0, 612500, 3350000, sd),
+	AS3711_REG(LDO_1, LDO_1_VOLTAGE, 7, 0x1f, 0, 1200000, 3300000, aldo),
+	AS3711_REG(LDO_2, LDO_2_VOLTAGE, 7, 0x1f, 0, 1200000, 3300000, aldo),
+	AS3711_REG(LDO_3, LDO_3_VOLTAGE, 7, 0x3f, 0, 900000, 3300000, dldo),
+	AS3711_REG(LDO_4, LDO_4_VOLTAGE, 7, 0x3f, 0, 900000, 3300000, dldo),
+	AS3711_REG(LDO_5, LDO_5_VOLTAGE, 7, 0x3f, 0, 900000, 3300000, dldo),
+	AS3711_REG(LDO_6, LDO_6_VOLTAGE, 7, 0x3f, 0, 900000, 3300000, dldo),
+	AS3711_REG(LDO_7, LDO_7_VOLTAGE, 7, 0x3f, 0, 900000, 3300000, dldo),
+	AS3711_REG(LDO_8, LDO_8_VOLTAGE, 7, 0x3f, 0, 900000, 3300000, dldo),
+	/* StepUp output voltage depends on supplying regulator */
+};
+
+#define AS3711_REGULATOR_NUM ARRAY_SIZE(as3711_reg_info)
+
+static int as3711_regulator_probe(struct platform_device *pdev)
+{
+	struct as3711_regulator_pdata *pdata = dev_get_platdata(&pdev->dev);
+	struct as3711 *as3711 = dev_get_drvdata(pdev->dev.parent);
+	struct regulator_init_data *reg_data;
+	struct regulator_config config = {.dev = &pdev->dev,};
+	struct as3711_regulator *reg = NULL;
+	struct as3711_regulator *regs;
+	struct regulator_dev *rdev;
+	struct as3711_regulator_info *ri;
+	int ret;
+	int id;
+
+	if (!pdata)
+		dev_dbg(&pdev->dev, "No platform data...\n");
+
+	regs = devm_kzalloc(&pdev->dev, AS3711_REGULATOR_NUM *
+			sizeof(struct as3711_regulator), GFP_KERNEL);
+	if (!regs) {
+		dev_err(&pdev->dev, "Memory allocation failed exiting..\n");
+		return -ENOMEM;
+	}
+
+	for (id = 0, ri = as3711_reg_info; id < AS3711_REGULATOR_NUM; ++id, ri++) {
+		reg_data = pdata ? pdata->init_data[id] : NULL;
+
+		/* No need to register if there is no regulator data */
+		if (!ri->desc.name)
+			continue;
+
+		reg = &regs[id];
+		reg->reg_info = ri;
+
+		config.init_data = reg_data;
+		config.driver_data = reg;
+		config.regmap = as3711->regmap;
+
+		rdev = regulator_register(&ri->desc, &config);
+		if (IS_ERR(rdev)) {
+			dev_err(&pdev->dev, "Failed to register regulator %s\n",
+				ri->desc.name);
+			ret = PTR_ERR(rdev);
+			goto eregreg;
+		}
+		reg->rdev = rdev;
+	}
+	platform_set_drvdata(pdev, regs);
+	return 0;
+
+eregreg:
+	while (--id >= 0)
+		regulator_unregister(regs[id].rdev);
+
+	return ret;
+}
+
+static int as3711_regulator_remove(struct platform_device *pdev)
+{
+	struct as3711_regulator *regs = platform_get_drvdata(pdev);
+	int id;
+
+	for (id = 0; id < AS3711_REGULATOR_NUM; ++id)
+		regulator_unregister(regs[id].rdev);
+	return 0;
+}
+
+static struct platform_driver as3711_regulator_driver = {
+	.driver	= {
+		.name	= "as3711-regulator",
+		.owner	= THIS_MODULE,
+	},
+	.probe		= as3711_regulator_probe,
+	.remove		= as3711_regulator_remove,
+};
+
+static int __init as3711_regulator_init(void)
+{
+	return platform_driver_register(&as3711_regulator_driver);
+}
+subsys_initcall(as3711_regulator_init);
+
+static void __exit as3711_regulator_exit(void)
+{
+	platform_driver_unregister(&as3711_regulator_driver);
+}
+module_exit(as3711_regulator_exit);
+
+MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>");
+MODULE_DESCRIPTION("AS3711 regulator driver");
+MODULE_ALIAS("platform:as3711-regulator");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index e872c8be080..59e08633372 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -1867,6 +1867,28 @@ int regulator_is_enabled(struct regulator *regulator)
 EXPORT_SYMBOL_GPL(regulator_is_enabled);
 
 /**
+ * regulator_can_change_voltage - check if regulator can change voltage
+ * @regulator: regulator source
+ *
+ * Returns positive if the regulator driver backing the source/client
+ * can change its voltage, false otherwise. Usefull for detecting fixed
+ * or dummy regulators and disabling voltage change logic in the client
+ * driver.
+ */
+int regulator_can_change_voltage(struct regulator *regulator)
+{
+	struct regulator_dev	*rdev = regulator->rdev;
+
+	if (rdev->constraints &&
+	    rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE &&
+	    rdev->desc->n_voltages > 1)
+		return 1;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(regulator_can_change_voltage);
+
+/**
  * regulator_count_voltages - count regulator_list_voltage() selectors
  * @regulator: regulator source
  *
diff --git a/drivers/regulator/wm831x-dcdc.c b/drivers/regulator/wm831x-dcdc.c
index 782c228a19b..416fe0a37f5 100644
--- a/drivers/regulator/wm831x-dcdc.c
+++ b/drivers/regulator/wm831x-dcdc.c
@@ -290,7 +290,7 @@ static int wm831x_buckv_set_voltage_sel(struct regulator_dev *rdev,
 	if (vsel > dcdc->dvs_vsel) {
 		ret = wm831x_set_bits(wm831x, dvs_reg,
 				      WM831X_DC1_DVS_VSEL_MASK,
-				      dcdc->dvs_vsel);
+				      vsel);
 		if (ret == 0)
 			dcdc->dvs_vsel = vsel;
 		else