diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 5ef2306..76039d5 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -1047,6 +1047,16 @@ config REGULATOR_RT5033
 	  RT5033 PMIC. The device supports multiple regulators like
 	  current source, LDO and Buck.
 
+config REGULATOR_RT5120
+	tristate "Richtek RT5120 PMIC Regulators"
+	depends on MFD_RT5120
+	help
+	  This adds support for voltage regulator in Richtek RT5120 PMIC.
+	  It integrates 4 channels buck controller, 1 channel LDO, 1 EXTEN
+	  to control external power source. Only BUCK1 is adjustable from
+	  600mV to 1395mV, per step 6.250mV. The others are all fixed voltage
+	  by external hardware circuit.
+
 config REGULATOR_RT5190A
 	tristate "Richtek RT5190A PMIC"
 	depends on I2C
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index 1b64ad5..32fce42 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -126,6 +126,7 @@ obj-$(CONFIG_REGULATOR_ROHM)	+= rohm-regulator.o
 obj-$(CONFIG_REGULATOR_RT4801)	+= rt4801-regulator.o
 obj-$(CONFIG_REGULATOR_RT4831)	+= rt4831-regulator.o
 obj-$(CONFIG_REGULATOR_RT5033)	+= rt5033-regulator.o
+obj-$(CONFIG_REGULATOR_RT5120)	+= rt5120-regulator.o
 obj-$(CONFIG_REGULATOR_RT5190A) += rt5190a-regulator.o
 obj-$(CONFIG_REGULATOR_RT6160)	+= rt6160-regulator.o
 obj-$(CONFIG_REGULATOR_RT6245)	+= rt6245-regulator.o
diff --git a/drivers/regulator/rt5120-regulator.c b/drivers/regulator/rt5120-regulator.c
new file mode 100644
index 00000000..c786564
--- /dev/null
+++ b/drivers/regulator/rt5120-regulator.c
@@ -0,0 +1,417 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+#include <linux/bits.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+#include <linux/regulator/of_regulator.h>
+
+#define RT5120_REG_PGSTAT	0x03
+#define RT5120_REG_CH1VID	0x06
+#define RT5120_REG_CH1SLPVID	0x07
+#define RT5120_REG_ENABLE	0x08
+#define RT5120_REG_MODECTL	0x09
+#define RT5120_REG_UVOVPROT	0x0A
+#define RT5120_REG_SLPCTL	0x0C
+#define RT5120_REG_INTSTAT	0x1E
+#define RT5120_REG_DISCHG	0x1F
+
+#define RT5120_OUTPG_MASK(rid)	BIT(rid + 1)
+#define RT5120_OUTUV_MASK(rid)	BIT(rid + 9)
+#define RT5120_OUTOV_MASK(rid)	BIT(rid + 16)
+#define RT5120_CH1VID_MASK	GENMASK(6, 0)
+#define RT5120_RIDEN_MASK(rid)	BIT(rid + 1)
+#define RT5120_RADEN_MASK(rid)	BIT(rid)
+#define RT5120_FPWM_MASK(rid)	BIT(rid + 1)
+#define RT5120_UVHICCUP_MASK	BIT(1)
+#define RT5120_OVHICCUP_MASK	BIT(0)
+#define RT5120_HOTDIE_MASK	BIT(1)
+
+#define RT5120_BUCK1_MINUV	600000
+#define RT5120_BUCK1_MAXUV	1393750
+#define RT5120_BUCK1_STEPUV	6250
+#define RT5120_BUCK1_NUM_VOLT	0x80
+
+#define RT5120_AUTO_MODE	0
+#define RT5120_FPWM_MODE	1
+
+enum {
+	RT5120_REGULATOR_BUCK1 = 0,
+	RT5120_REGULATOR_BUCK2,
+	RT5120_REGULATOR_BUCK3,
+	RT5120_REGULATOR_BUCK4,
+	RT5120_REGULATOR_LDO,
+	RT5120_REGULATOR_EXTEN,
+	RT5120_MAX_REGULATOR
+};
+
+struct rt5120_priv {
+	struct device *dev;
+	struct regmap *regmap;
+	struct regulator_desc rdesc[RT5120_MAX_REGULATOR];
+};
+
+static int rt5120_buck_set_mode(struct regulator_dev *rdev, unsigned int mode)
+{
+	struct regmap *regmap = rdev_get_regmap(rdev);
+	int rid = rdev_get_id(rdev);
+	unsigned int mask = RT5120_FPWM_MASK(rid), val;
+
+	switch (mode) {
+	case REGULATOR_MODE_NORMAL:
+		val = 0;
+		break;
+	case REGULATOR_MODE_FAST:
+		val = RT5120_FPWM_MASK(rid);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return regmap_update_bits(regmap, RT5120_REG_MODECTL, mask, val);
+}
+
+static unsigned int rt5120_buck_get_mode(struct regulator_dev *rdev)
+{
+	struct regmap *regmap = rdev_get_regmap(rdev);
+	int ret, rid = rdev_get_id(rdev);
+	unsigned int val;
+
+	ret = regmap_read(regmap, RT5120_REG_MODECTL, &val);
+	if (ret)
+		return REGULATOR_MODE_INVALID;
+
+	if (val & RT5120_FPWM_MASK(rid))
+		return REGULATOR_MODE_FAST;
+
+	return REGULATOR_MODE_NORMAL;
+}
+
+static int rt5120_regulator_get_error_flags(struct regulator_dev *rdev,
+					    unsigned int *flags)
+{
+	struct regmap *regmap = rdev_get_regmap(rdev);
+	unsigned int stat, hd_stat, cur_flags = 0;
+	int rid = rdev_get_id(rdev), ret;
+
+	/*
+	 * reg 0x03/0x04/0x05 to indicate PG/UV/OV
+	 * use block read to descrease I/O xfer time
+	 */
+	ret = regmap_raw_read(regmap, RT5120_REG_PGSTAT, &stat, 3);
+	if (ret)
+		return ret;
+
+	ret = regmap_read(regmap, RT5120_REG_INTSTAT, &hd_stat);
+	if (ret)
+		return ret;
+
+	if (!(stat & RT5120_OUTPG_MASK(rid))) {
+		if (stat & RT5120_OUTUV_MASK(rid))
+			cur_flags |= REGULATOR_ERROR_UNDER_VOLTAGE;
+
+		if (stat & RT5120_OUTOV_MASK(rid))
+			cur_flags |= REGULATOR_ERROR_REGULATION_OUT;
+	}
+
+	if (hd_stat & RT5120_HOTDIE_MASK)
+		cur_flags |= REGULATOR_ERROR_OVER_TEMP;
+
+	*flags = cur_flags;
+	return 0;
+}
+
+static int rt5120_buck1_set_suspend_voltage(struct regulator_dev *rdev, int uV)
+{
+	struct regmap *regmap = rdev_get_regmap(rdev);
+	int sel;
+
+	if (uV < RT5120_BUCK1_MINUV || uV > RT5120_BUCK1_MAXUV)
+		return -EINVAL;
+
+	sel = (uV - RT5120_BUCK1_MINUV) / RT5120_BUCK1_STEPUV;
+	return regmap_write(regmap, RT5120_REG_CH1SLPVID, sel);
+}
+
+static int rt5120_regulator_set_suspend_enable(struct regulator_dev *rdev)
+{
+	struct regmap *regmap = rdev_get_regmap(rdev);
+	int rid = rdev_get_id(rdev);
+	unsigned int mask = RT5120_RIDEN_MASK(rid);
+
+	return regmap_update_bits(regmap, RT5120_REG_SLPCTL, mask, mask);
+}
+
+static int rt5120_regulator_set_suspend_disable(struct regulator_dev *rdev)
+{
+	struct regmap *regmap = rdev_get_regmap(rdev);
+	int rid = rdev_get_id(rdev);
+	unsigned int mask = RT5120_RIDEN_MASK(rid);
+
+	return regmap_update_bits(regmap, RT5120_REG_SLPCTL, mask, 0);
+}
+
+static const struct regulator_ops rt5120_buck1_ops = {
+	.enable = regulator_enable_regmap,
+	.disable = regulator_disable_regmap,
+	.is_enabled = regulator_is_enabled_regmap,
+	.list_voltage = regulator_list_voltage_linear,
+	.set_voltage_sel = regulator_set_voltage_sel_regmap,
+	.get_voltage_sel = regulator_get_voltage_sel_regmap,
+	.set_active_discharge = regulator_set_active_discharge_regmap,
+	.set_mode = rt5120_buck_set_mode,
+	.get_mode = rt5120_buck_get_mode,
+	.get_error_flags = rt5120_regulator_get_error_flags,
+	.set_suspend_voltage = rt5120_buck1_set_suspend_voltage,
+	.set_suspend_enable = rt5120_regulator_set_suspend_enable,
+	.set_suspend_disable = rt5120_regulator_set_suspend_disable,
+};
+
+static const struct regulator_ops rt5120_buck234_ops = {
+	.enable = regulator_enable_regmap,
+	.disable = regulator_disable_regmap,
+	.is_enabled = regulator_is_enabled_regmap,
+	.set_active_discharge = regulator_set_active_discharge_regmap,
+	.set_mode = rt5120_buck_set_mode,
+	.get_mode = rt5120_buck_get_mode,
+	.get_error_flags = rt5120_regulator_get_error_flags,
+	.set_suspend_enable = rt5120_regulator_set_suspend_enable,
+	.set_suspend_disable = rt5120_regulator_set_suspend_disable,
+};
+
+static const struct regulator_ops rt5120_ldo_ops = {
+	.enable = regulator_enable_regmap,
+	.disable = regulator_disable_regmap,
+	.is_enabled = regulator_is_enabled_regmap,
+	.set_active_discharge = regulator_set_active_discharge_regmap,
+	.get_error_flags = rt5120_regulator_get_error_flags,
+	.set_suspend_enable = rt5120_regulator_set_suspend_enable,
+	.set_suspend_disable = rt5120_regulator_set_suspend_disable,
+};
+
+static const struct regulator_ops rt5120_exten_ops = {
+	.enable = regulator_enable_regmap,
+	.disable = regulator_disable_regmap,
+	.is_enabled = regulator_is_enabled_regmap,
+	.set_suspend_enable = rt5120_regulator_set_suspend_enable,
+	.set_suspend_disable = rt5120_regulator_set_suspend_disable,
+};
+
+static unsigned int rt5120_buck_of_map_mode(unsigned int mode)
+{
+	switch (mode) {
+	case RT5120_AUTO_MODE:
+		return REGULATOR_MODE_NORMAL;
+	case RT5120_FPWM_MODE:
+		return REGULATOR_MODE_FAST;
+	default:
+		return REGULATOR_MODE_INVALID;
+	}
+}
+
+static void rt5120_fillin_regulator_desc(struct regulator_desc *desc, int rid)
+{
+	static const char * const name[] = { "buck1", "buck2", "buck3", "buck4",
+					     "ldo", "exten" };
+	static const char * const sname[] = { "vin1", "vin2", "vin3", "vin4",
+					      "vinldo", NULL };
+
+	desc->name = name[rid];
+	desc->supply_name = sname[rid];
+	desc->owner = THIS_MODULE;
+	desc->type = REGULATOR_VOLTAGE;
+	desc->id = rid;
+	desc->enable_reg = RT5120_REG_ENABLE;
+	desc->enable_mask = RT5120_RIDEN_MASK(rid);
+	desc->active_discharge_reg = RT5120_REG_DISCHG;
+	desc->active_discharge_mask = RT5120_RADEN_MASK(rid);
+	desc->active_discharge_on = RT5120_RADEN_MASK(rid);
+
+	switch (rid) {
+	case RT5120_REGULATOR_BUCK1:
+		desc->of_map_mode = rt5120_buck_of_map_mode;
+		desc->min_uV = RT5120_BUCK1_MINUV;
+		desc->uV_step = RT5120_BUCK1_STEPUV;
+		desc->n_voltages = RT5120_BUCK1_NUM_VOLT;
+		desc->vsel_reg = RT5120_REG_CH1VID,
+		desc->vsel_mask = RT5120_CH1VID_MASK,
+		desc->ops = &rt5120_buck1_ops;
+		break;
+	case RT5120_REGULATOR_BUCK2 ... RT5120_REGULATOR_BUCK4:
+		desc->of_map_mode = rt5120_buck_of_map_mode;
+		desc->n_voltages = 1;
+		desc->ops = &rt5120_buck234_ops;
+		break;
+	case RT5120_REGULATOR_LDO:
+		desc->n_voltages = 1;
+		desc->ops = &rt5120_ldo_ops;
+		break;
+	default:
+		desc->n_voltages = 1;
+		desc->ops = &rt5120_exten_ops;
+		break;
+	}
+}
+
+static int rt5120_of_parse_cb(struct rt5120_priv *priv, int rid,
+			      struct of_regulator_match *match)
+{
+	struct regulator_desc *desc = priv->rdesc + rid;
+	struct regulator_init_data *init_data = match->init_data;
+
+	if (!init_data || rid == RT5120_REGULATOR_BUCK1)
+		return 0;
+
+	if (init_data->constraints.min_uV != init_data->constraints.max_uV) {
+		dev_err(priv->dev, "Variable voltage for fixed regulator\n");
+		return -EINVAL;
+	}
+
+	desc->fixed_uV = init_data->constraints.min_uV;
+	init_data->constraints.apply_uV = 0;
+	return 0;
+}
+
+static struct of_regulator_match rt5120_regu_match[RT5120_MAX_REGULATOR] = {
+	[RT5120_REGULATOR_BUCK1] = { .name = "buck1", },
+	[RT5120_REGULATOR_BUCK2] = { .name = "buck2", },
+	[RT5120_REGULATOR_BUCK3] = { .name = "buck3", },
+	[RT5120_REGULATOR_BUCK4] = { .name = "buck4", },
+	[RT5120_REGULATOR_LDO] = { .name = "ldo", },
+	[RT5120_REGULATOR_EXTEN] = { .name = "exten", }
+};
+
+static int rt5120_parse_regulator_dt_data(struct rt5120_priv *priv)
+{
+	struct device *dev = priv->dev->parent;
+	struct device_node *reg_node;
+	int i, ret;
+
+	for (i = 0; i < RT5120_MAX_REGULATOR; i++) {
+		rt5120_fillin_regulator_desc(priv->rdesc + i, i);
+
+		rt5120_regu_match[i].desc = priv->rdesc + i;
+	}
+
+	reg_node = of_get_child_by_name(dev->of_node, "regulators");
+	if (!reg_node) {
+		dev_err(priv->dev, "Couldn't find 'regulators' node\n");
+		return -ENODEV;
+	}
+
+	ret = of_regulator_match(priv->dev, reg_node, rt5120_regu_match,
+				 ARRAY_SIZE(rt5120_regu_match));
+
+	of_node_put(reg_node);
+
+	if (ret < 0) {
+		dev_err(priv->dev,
+			"Error parsing regulator init data (%d)\n", ret);
+		return ret;
+	}
+
+	for (i = 0; i < RT5120_MAX_REGULATOR; i++) {
+		ret = rt5120_of_parse_cb(priv, i, rt5120_regu_match + i);
+		if (ret) {
+			dev_err(priv->dev, "Failed in [%d] of_passe_cb\n", i);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+static int rt5120_device_property_init(struct rt5120_priv *priv)
+{
+	struct device *dev = priv->dev->parent;
+	bool prot_enable;
+	unsigned int prot_enable_val = 0;
+
+	/* Assign UV/OV HW protection behavior */
+	prot_enable = device_property_read_bool(dev,
+					"richtek,enable-undervolt-hiccup");
+	if (prot_enable)
+		prot_enable_val |= RT5120_UVHICCUP_MASK;
+
+	prot_enable = device_property_read_bool(dev,
+					"richtek,enable-overvolt-hiccup");
+	if (prot_enable)
+		prot_enable_val |= RT5120_OVHICCUP_MASK;
+
+	return regmap_update_bits(priv->regmap, RT5120_REG_UVOVPROT,
+				  RT5120_UVHICCUP_MASK | RT5120_OVHICCUP_MASK,
+				  prot_enable_val);
+}
+
+static int rt5120_regulator_probe(struct platform_device *pdev)
+{
+	struct rt5120_priv *priv;
+	struct regulator_dev *rdev;
+	struct regulator_config config = {};
+	int i, ret;
+
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->dev = &pdev->dev;
+
+	priv->regmap = dev_get_regmap(pdev->dev.parent, NULL);
+	if (!priv->regmap) {
+		dev_err(&pdev->dev, "Failed to init regmap\n");
+		return -ENODEV;
+	}
+
+	ret = rt5120_device_property_init(priv);
+	if (ret) {
+		dev_err(&pdev->dev, "Failed to do property init\n");
+		return ret;
+	}
+
+	ret = rt5120_parse_regulator_dt_data(priv);
+	if (ret) {
+		dev_err(&pdev->dev, "Failed to parse dt data\n");
+		return ret;
+	}
+
+	config.dev = &pdev->dev;
+	config.regmap = priv->regmap;
+
+	for (i = 0; i < RT5120_MAX_REGULATOR; i++) {
+		config.of_node = rt5120_regu_match[i].of_node;
+		config.init_data = rt5120_regu_match[i].init_data;
+
+		rdev = devm_regulator_register(&pdev->dev, priv->rdesc + i,
+					       &config);
+		if (IS_ERR(rdev)) {
+			dev_err(&pdev->dev,
+				"Failed to register regulator [%d]\n", i);
+			return PTR_ERR(rdev);
+		}
+	}
+
+	return 0;
+}
+
+static const struct platform_device_id rt5120_regulator_dev_table[] = {
+	{ "rt5120-regulator", 0 },
+	{}
+};
+MODULE_DEVICE_TABLE(platform, rt5120_regulator_dev_table);
+
+static struct platform_driver rt5120_regulator_driver = {
+	.driver = {
+		.name = "rt5120-regulator",
+	},
+	.id_table = rt5120_regulator_dev_table,
+	.probe = rt5120_regulator_probe,
+};
+module_platform_driver(rt5120_regulator_driver);
+
+MODULE_AUTHOR("ChiYuan Huang <cy_huang@richtek.com>");
+MODULE_DESCRIPTION("Richtek RT5120 regulator driver");
+MODULE_LICENSE("GPL v2");
