regulator: bd718x7: support ROHM BD71837 and BD71847 PMICs

BD71837 and BD71847 is PMIC intended for powering single-core,
dual-core, and quad-core SoC’s such as NXP-i.MX 8M. BD71847
is used for example on NXP imx8mm EVK.

Add regulator driver for ROHM BD71837 and BD71847 PMICs.
BD71837 contains 8 bucks and 7 LDOS. BD71847 is reduced
version containing 6 bucks and 6 LDOs. Voltages for DVS
bucks (1-4 on BD71837, 1 and 2 on BD71847) can be adjusted
when regulators are enabled. For other bucks and LDOs we may
have over- or undershooting if voltage is adjusted when
regulator is enabled. Thus this is prevented by default.

BD718x7 has a quirk which may leave power output disabled
after reset if enable/disable state was controlled by SW.
Thus the SW control is only allowed for BD71837  bucks
3 and 4 by default. The impact of this limitation must be
evaluated board-by board and restrictions may need to be
modified. (Linux driver get's these limitations from DT and we
may want to implement same on u-Boot driver).

Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

4 files changed, 513 insertions, 5 deletions

diff --git a/drivers/power/pmic/bd71837.c b/drivers/power/pmic/bd71837.c
index 24d9f7fab7..e292d42a8c 100644
--- a/drivers/power/pmic/bd71837.c
+++ b/drivers/power/pmic/bd71837.c
@@ -3,6 +3,8 @@
  * Copyright 2018 NXP
  */
 
+#define DEBUG
+
 #include <common.h>
 #include <errno.h>
 #include <dm.h>
@@ -15,15 +17,15 @@ DECLARE_GLOBAL_DATA_PTR;
 
 static const struct pmic_child_info pmic_children_info[] = {
 	/* buck */
-	{ .prefix = "b", .driver = BD71837_REGULATOR_DRIVER},
+	{ .prefix = "b", .driver = BD718XX_REGULATOR_DRIVER},
 	/* ldo */
-	{ .prefix = "l", .driver = BD71837_REGULATOR_DRIVER},
+	{ .prefix = "l", .driver = BD718XX_REGULATOR_DRIVER},
 	{ },
 };
 
 static int bd71837_reg_count(struct udevice *dev)
 {
-	return BD71837_REG_NUM;
+	return BD718XX_MAX_REGISTER - 1;
 }
 
 static int bd71837_write(struct udevice *dev, uint reg, const uint8_t *buff,
@@ -54,7 +56,7 @@ static int bd71837_bind(struct udevice *dev)
 
 	regulators_node = dev_read_subnode(dev, "regulators");
 	if (!ofnode_valid(regulators_node)) {
-		debug("%s: %s regulators subnode not found!", __func__,
+		debug("%s: %s regulators subnode not found!\n", __func__,
 		      dev->name);
 		return -ENXIO;
 	}
@@ -69,6 +71,24 @@ static int bd71837_bind(struct udevice *dev)
 	return 0;
 }
 
+static int bd718x7_probe(struct udevice *dev)
+{
+	int ret;
+	uint8_t mask = BD718XX_REGLOCK_PWRSEQ | BD718XX_REGLOCK_VREG;
+
+	/* Unlock the PMIC regulator control before probing the children */
+	ret = pmic_clrsetbits(dev, BD718XX_REGLOCK, mask, 0);
+	if (ret) {
+		debug("%s: %s Failed to unlock regulator control\n", __func__,
+		      dev->name);
+		return ret;
+	}
+	debug("%s: '%s' - BD718x7 PMIC registers unlocked\n", __func__,
+	      dev->name);
+
+	return 0;
+}
+
 static struct dm_pmic_ops bd71837_ops = {
 	.reg_count = bd71837_reg_count,
 	.read = bd71837_read,
@@ -76,7 +96,8 @@ static struct dm_pmic_ops bd71837_ops = {
 };
 
 static const struct udevice_id bd71837_ids[] = {
-	{ .compatible = "rohm,bd71837", .data = 0x4b, },
+	{ .compatible = "rohm,bd71837", .data = ROHM_CHIP_TYPE_BD71837, },
+	{ .compatible = "rohm,bd71847", .data = ROHM_CHIP_TYPE_BD71847, },
 	{ }
 };
 
@@ -85,5 +106,6 @@ U_BOOT_DRIVER(pmic_bd71837) = {
 	.id = UCLASS_PMIC,
 	.of_match = bd71837_ids,
 	.bind = bd71837_bind,
+	.probe = bd718x7_probe,
 	.ops = &bd71837_ops,
 };
diff --git a/drivers/power/regulator/Kconfig b/drivers/power/regulator/Kconfig
index 337e9e7471..9aa00fad42 100644
--- a/drivers/power/regulator/Kconfig
+++ b/drivers/power/regulator/Kconfig
@@ -43,6 +43,23 @@ config REGULATOR_AS3722
 	  but does not yet support change voltages. Currently this must be
 	  done using direct register writes to the PMIC.
 
+config DM_REGULATOR_BD71837
+	bool "Enable Driver Model for ROHM BD71837/BD71847 regulators"
+	depends on DM_REGULATOR && DM_PMIC_BD71837
+	help
+	This config enables implementation of driver-model regulator uclass
+	features for regulators on ROHM BD71837 and BD71847 PMICs.
+	BD71837 contains 8 bucks and 7 LDOS. BD71847 is reduced version
+	containing 6 bucks and 6 LDOs. The driver implements get/set api for
+	value and enable.
+
+config SPL_DM_REGULATOR_BD71837
+	bool "Enable Driver Model for ROHM BD71837/BD71847 regulators in SPL"
+	depends on DM_REGULATOR_BD71837
+	help
+	This config enables implementation of driver-model regulator uclass
+	features for regulators on ROHM BD71837 and BD71847 in SPL.
+
 config DM_REGULATOR_PFUZE100
 	bool "Enable Driver Model for REGULATOR PFUZE100"
 	depends on DM_REGULATOR && DM_PMIC_PFUZE100
diff --git a/drivers/power/regulator/Makefile b/drivers/power/regulator/Makefile
index e728b73aee..6a3d4bbee4 100644
--- a/drivers/power/regulator/Makefile
+++ b/drivers/power/regulator/Makefile
@@ -9,6 +9,7 @@ obj-$(CONFIG_REGULATOR_ACT8846) += act8846.o
 obj-$(CONFIG_REGULATOR_AS3722)	+= as3722_regulator.o
 obj-$(CONFIG_DM_REGULATOR_MAX77686) += max77686.o
 obj-$(CONFIG_$(SPL_)DM_PMIC_PFUZE100) += pfuze100.o
+obj-$(CONFIG_$(SPL_)DM_REGULATOR_BD71837) += bd71837.o
 obj-$(CONFIG_$(SPL_)REGULATOR_PWM) += pwm_regulator.o
 obj-$(CONFIG_$(SPL_)DM_REGULATOR_FAN53555) += fan53555.o
 obj-$(CONFIG_$(SPL_)DM_REGULATOR_COMMON) += regulator_common.o
diff --git a/drivers/power/regulator/bd71837.c b/drivers/power/regulator/bd71837.c
new file mode 100644
index 0000000000..575429aa2d
--- /dev/null
+++ b/drivers/power/regulator/bd71837.c
@@ -0,0 +1,468 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2019 ROHM Semiconductors
+ *
+ * ROHM BD71837 regulator driver
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <power/bd71837.h>
+#include <power/pmic.h>
+#include <power/regulator.h>
+
+#define HW_STATE_CONTROL 0
+#define DEBUG
+
+/**
+ * struct bd71837_vrange - describe linear range of voltages
+ *
+ * @min_volt:	smallest voltage in range
+ * @step:	how much voltage changes at each selector step
+ * @min_sel:	smallest selector in the range
+ * @max_sel:	maximum selector in the range
+ * @rangeval:	register value used to select this range if selectible
+ *		ranges are supported
+ */
+struct bd71837_vrange {
+	unsigned int	min_volt;
+	unsigned int	step;
+	u8		min_sel;
+	u8		max_sel;
+	u8		rangeval;
+};
+
+/**
+ * struct bd71837_platdata - describe regulator control registers
+ *
+ * @name:	name of the regulator. Used for matching the dt-entry
+ * @enable_reg:	register address used to enable/disable regulator
+ * @enablemask:	register mask used to enable/disable regulator
+ * @volt_reg:	register address used to configure regulator voltage
+ * @volt_mask:	register mask used to configure regulator voltage
+ * @ranges:	pointer to ranges of regulator voltages and matching register
+ *		values
+ * @numranges:	number of voltage ranges pointed by ranges
+ * @rangemask:	mask for selecting used ranges if multiple ranges are supported
+ * @sel_mask:	bit to toggle in order to transfer the register control to SW
+ * @dvs:	whether the voltage can be changed when regulator is enabled
+ */
+struct bd71837_platdata {
+	const char		*name;
+	u8			enable_reg;
+	u8			enablemask;
+	u8			volt_reg;
+	u8			volt_mask;
+	struct bd71837_vrange	*ranges;
+	unsigned int		numranges;
+	u8			rangemask;
+	u8			sel_mask;
+	bool			dvs;
+};
+
+#define BD_RANGE(_min, _vstep, _sel_low, _sel_hi, _range_sel) \
+{ \
+	.min_volt = (_min), .step = (_vstep), .min_sel = (_sel_low), \
+	.max_sel = (_sel_hi), .rangeval = (_range_sel) \
+}
+
+#define BD_DATA(_name, enreg, enmask, vreg, vmask, _range, rmask, _dvs, sel) \
+{ \
+	.name = (_name), .enable_reg = (enreg), .enablemask = (enmask), \
+	.volt_reg = (vreg), .volt_mask = (vmask), .ranges = (_range), \
+	.numranges = ARRAY_SIZE(_range), .rangemask = (rmask), .dvs = (_dvs), \
+	.sel_mask = (sel) \
+}
+
+static struct bd71837_vrange dvs_buck_vranges[] = {
+	BD_RANGE(700000, 10000, 0, 0x3c, 0),
+	BD_RANGE(1300000, 0, 0x3d, 0x3f, 0),
+};
+
+static struct bd71837_vrange bd71847_buck3_vranges[] = {
+	BD_RANGE(700000, 100000, 0x00, 0x03, 0),
+	BD_RANGE(1050000, 50000, 0x04, 0x05, 0),
+	BD_RANGE(1200000, 150000, 0x06, 0x07, 0),
+	BD_RANGE(550000, 50000, 0x0, 0x7, 0x40),
+	BD_RANGE(675000, 100000, 0x0, 0x3, 0x80),
+	BD_RANGE(1025000, 50000, 0x4, 0x5, 0x80),
+	BD_RANGE(1175000, 150000, 0x6, 0x7, 0x80),
+};
+
+static struct bd71837_vrange bd71847_buck4_vranges[] = {
+	BD_RANGE(3000000, 100000, 0x00, 0x03, 0),
+	BD_RANGE(2600000, 100000, 0x00, 0x03, 40),
+};
+
+static struct bd71837_vrange bd71837_buck5_vranges[] = {
+	BD_RANGE(700000, 100000, 0, 0x3, 0),
+	BD_RANGE(1050000, 50000, 0x04, 0x05, 0),
+	BD_RANGE(1200000, 150000, 0x06, 0x07, 0),
+	BD_RANGE(675000, 100000, 0x0, 0x3, 0x80),
+	BD_RANGE(1025000, 50000, 0x04, 0x05, 0x80),
+	BD_RANGE(1175000, 150000, 0x06, 0x07, 0x80),
+};
+
+static struct bd71837_vrange bd71837_buck6_vranges[] = {
+	BD_RANGE(3000000, 100000, 0x00, 0x03, 0),
+};
+
+static struct bd71837_vrange nodvs_buck3_vranges[] = {
+	BD_RANGE(1605000, 90000, 0, 1, 0),
+	BD_RANGE(1755000, 45000, 2, 4, 0),
+	BD_RANGE(1905000, 45000, 5, 7, 0),
+};
+
+static struct bd71837_vrange nodvs_buck4_vranges[] = {
+	BD_RANGE(800000, 10000, 0x00, 0x3C, 0),
+};
+
+static struct bd71837_vrange ldo1_vranges[] = {
+	BD_RANGE(3000000, 100000, 0x00, 0x03, 0),
+	BD_RANGE(1600000, 100000, 0x00, 0x03, 0x20),
+};
+
+static struct bd71837_vrange ldo2_vranges[] = {
+	BD_RANGE(900000, 0, 0, 0, 0),
+	BD_RANGE(800000, 0, 1, 1, 0),
+};
+
+static struct bd71837_vrange ldo3_vranges[] = {
+	BD_RANGE(1800000, 100000, 0x00, 0x0f, 0),
+};
+
+static struct bd71837_vrange ldo4_vranges[] = {
+	BD_RANGE(900000, 100000, 0x00, 0x09, 0),
+};
+
+static struct bd71837_vrange bd71837_ldo5_vranges[] = {
+	BD_RANGE(1800000, 100000, 0x00, 0x0f, 0),
+};
+
+static struct bd71837_vrange bd71847_ldo5_vranges[] = {
+	BD_RANGE(1800000, 100000, 0x00, 0x0f, 0),
+	BD_RANGE(800000, 100000, 0x00, 0x0f, 0x20),
+};
+
+static struct bd71837_vrange ldo6_vranges[] = {
+	BD_RANGE(900000, 100000, 0x00, 0x09, 0),
+};
+
+static struct bd71837_vrange ldo7_vranges[] = {
+	BD_RANGE(1800000, 100000, 0x00, 0x0f, 0),
+};
+
+/*
+ * We use enable mask 'HW_STATE_CONTROL' to indicate that this regulator
+ * must not be enabled or disabled by SW. The typical use-case for BD71837
+ * is powering NXP i.MX8. In this use-case we (for now) only allow control
+ * for BUCK3 and BUCK4 which are not boot critical.
+ */
+static struct bd71837_platdata bd71837_reg_data[] = {
+/* Bucks 1-4 which support dynamic voltage scaling */
+	BD_DATA("BUCK1", BD718XX_BUCK1_CTRL, HW_STATE_CONTROL,
+		BD718XX_BUCK1_VOLT_RUN, DVS_BUCK_RUN_MASK, dvs_buck_vranges, 0,
+		true, BD718XX_BUCK_SEL),
+	BD_DATA("BUCK2", BD718XX_BUCK2_CTRL, HW_STATE_CONTROL,
+		BD718XX_BUCK2_VOLT_RUN, DVS_BUCK_RUN_MASK, dvs_buck_vranges, 0,
+		true, BD718XX_BUCK_SEL),
+	BD_DATA("BUCK3", BD71837_BUCK3_CTRL, BD718XX_BUCK_EN,
+		BD71837_BUCK3_VOLT_RUN, DVS_BUCK_RUN_MASK, dvs_buck_vranges, 0,
+		true, BD718XX_BUCK_SEL),
+	BD_DATA("BUCK4", BD71837_BUCK4_CTRL, BD718XX_BUCK_EN,
+		BD71837_BUCK4_VOLT_RUN, DVS_BUCK_RUN_MASK, dvs_buck_vranges, 0,
+		true, BD718XX_BUCK_SEL),
+/* Bucks 5-8 which do not support dynamic voltage scaling */
+	BD_DATA("BUCK5", BD718XX_1ST_NODVS_BUCK_CTRL, HW_STATE_CONTROL,
+		BD718XX_1ST_NODVS_BUCK_VOLT, BD718XX_1ST_NODVS_BUCK_MASK,
+		bd71837_buck5_vranges, 0x80, false, BD718XX_BUCK_SEL),
+	BD_DATA("BUCK6", BD718XX_2ND_NODVS_BUCK_CTRL, HW_STATE_CONTROL,
+		BD718XX_2ND_NODVS_BUCK_VOLT, BD71837_BUCK6_MASK,
+		bd71837_buck6_vranges, 0, false, BD718XX_BUCK_SEL),
+	BD_DATA("BUCK7", BD718XX_3RD_NODVS_BUCK_CTRL, HW_STATE_CONTROL,
+		BD718XX_3RD_NODVS_BUCK_VOLT, BD718XX_3RD_NODVS_BUCK_MASK,
+		nodvs_buck3_vranges, 0, false, BD718XX_BUCK_SEL),
+	BD_DATA("BUCK8", BD718XX_4TH_NODVS_BUCK_CTRL, HW_STATE_CONTROL,
+		BD718XX_4TH_NODVS_BUCK_VOLT, BD718XX_4TH_NODVS_BUCK_MASK,
+		nodvs_buck4_vranges, 0, false, BD718XX_BUCK_SEL),
+/* LDOs */
+	BD_DATA("LDO1", BD718XX_LDO1_VOLT, HW_STATE_CONTROL, BD718XX_LDO1_VOLT,
+		BD718XX_LDO1_MASK, ldo1_vranges, 0x20, false, BD718XX_LDO_SEL),
+	BD_DATA("LDO2", BD718XX_LDO2_VOLT, HW_STATE_CONTROL, BD718XX_LDO2_VOLT,
+		BD718XX_LDO2_MASK, ldo2_vranges, 0, false, BD718XX_LDO_SEL),
+	BD_DATA("LDO3", BD718XX_LDO3_VOLT, HW_STATE_CONTROL, BD718XX_LDO3_VOLT,
+		BD718XX_LDO3_MASK, ldo3_vranges, 0, false, BD718XX_LDO_SEL),
+	BD_DATA("LDO4", BD718XX_LDO4_VOLT, HW_STATE_CONTROL, BD718XX_LDO4_VOLT,
+		BD718XX_LDO4_MASK, ldo4_vranges, 0, false, BD718XX_LDO_SEL),
+	BD_DATA("LDO5", BD718XX_LDO5_VOLT, HW_STATE_CONTROL, BD718XX_LDO5_VOLT,
+		BD71837_LDO5_MASK, bd71837_ldo5_vranges, 0, false,
+		BD718XX_LDO_SEL),
+	BD_DATA("LDO6", BD718XX_LDO6_VOLT, HW_STATE_CONTROL, BD718XX_LDO6_VOLT,
+		BD718XX_LDO6_MASK, ldo6_vranges, 0, false, BD718XX_LDO_SEL),
+	BD_DATA("LDO7", BD71837_LDO7_VOLT, HW_STATE_CONTROL, BD71837_LDO7_VOLT,
+		BD71837_LDO7_MASK, ldo7_vranges, 0, false, BD718XX_LDO_SEL),
+};
+
+static struct bd71837_platdata bd71847_reg_data[] = {
+/* Bucks 1 and 2 which support dynamic voltage scaling */
+	BD_DATA("BUCK1", BD718XX_BUCK1_CTRL, HW_STATE_CONTROL,
+		BD718XX_BUCK1_VOLT_RUN, DVS_BUCK_RUN_MASK, dvs_buck_vranges, 0,
+		true, BD718XX_BUCK_SEL),
+	BD_DATA("BUCK2", BD718XX_BUCK2_CTRL, HW_STATE_CONTROL,
+		BD718XX_BUCK2_VOLT_RUN, DVS_BUCK_RUN_MASK, dvs_buck_vranges, 0,
+		true, BD718XX_BUCK_SEL),
+/* Bucks 3-6 which do not support dynamic voltage scaling */
+	BD_DATA("BUCK3", BD718XX_1ST_NODVS_BUCK_CTRL, HW_STATE_CONTROL,
+		BD718XX_1ST_NODVS_BUCK_VOLT, BD718XX_1ST_NODVS_BUCK_MASK,
+		bd71847_buck3_vranges, 0xc0, false, BD718XX_BUCK_SEL),
+	BD_DATA("BUCK4", BD718XX_2ND_NODVS_BUCK_CTRL, HW_STATE_CONTROL,
+		BD718XX_2ND_NODVS_BUCK_VOLT, BD71837_BUCK6_MASK,
+		bd71847_buck4_vranges, 0x40, false, BD718XX_BUCK_SEL),
+	BD_DATA("BUCK5", BD718XX_3RD_NODVS_BUCK_CTRL, HW_STATE_CONTROL,
+		BD718XX_3RD_NODVS_BUCK_VOLT, BD718XX_3RD_NODVS_BUCK_MASK,
+		nodvs_buck3_vranges, 0, false, BD718XX_BUCK_SEL),
+	BD_DATA("BUCK6", BD718XX_4TH_NODVS_BUCK_CTRL, HW_STATE_CONTROL,
+		BD718XX_4TH_NODVS_BUCK_VOLT, BD718XX_4TH_NODVS_BUCK_MASK,
+		nodvs_buck4_vranges, 0, false, BD718XX_BUCK_SEL),
+/* LDOs */
+	BD_DATA("LDO1", BD718XX_LDO1_VOLT, HW_STATE_CONTROL, BD718XX_LDO1_VOLT,
+		BD718XX_LDO1_MASK, ldo1_vranges, 0x20, false, BD718XX_LDO_SEL),
+	BD_DATA("LDO2", BD718XX_LDO2_VOLT, HW_STATE_CONTROL, BD718XX_LDO2_VOLT,
+		BD718XX_LDO2_MASK, ldo2_vranges, 0, false, BD718XX_LDO_SEL),
+	BD_DATA("LDO3", BD718XX_LDO3_VOLT, HW_STATE_CONTROL, BD718XX_LDO3_VOLT,
+		BD718XX_LDO3_MASK, ldo3_vranges, 0, false, BD718XX_LDO_SEL),
+	BD_DATA("LDO4", BD718XX_LDO4_VOLT, HW_STATE_CONTROL, BD718XX_LDO4_VOLT,
+		BD718XX_LDO4_MASK, ldo4_vranges, 0, false, BD718XX_LDO_SEL),
+	BD_DATA("LDO5", BD718XX_LDO5_VOLT, HW_STATE_CONTROL, BD718XX_LDO5_VOLT,
+		BD71847_LDO5_MASK, bd71847_ldo5_vranges, 0x20, false,
+		BD718XX_LDO_SEL),
+	BD_DATA("LDO6", BD718XX_LDO6_VOLT, HW_STATE_CONTROL, BD718XX_LDO6_VOLT,
+		BD718XX_LDO6_MASK, ldo6_vranges, 0, false, BD718XX_LDO_SEL),
+};
+
+static int vrange_find_value(struct bd71837_vrange *r, unsigned int sel,
+			     unsigned int *val)
+{
+	if (!val || sel < r->min_sel || sel > r->max_sel)
+		return -EINVAL;
+
+	*val = r->min_volt + r->step * (sel - r->min_sel);
+	return 0;
+}
+
+static int vrange_find_selector(struct bd71837_vrange *r, int val,
+				unsigned int *sel)
+{
+	int ret = -EINVAL;
+	int num_vals = r->max_sel - r->min_sel + 1;
+
+	if (val >= r->min_volt &&
+	    val <= r->min_volt + r->step * (num_vals - 1)) {
+		if (r->step) {
+			*sel = r->min_sel + ((val - r->min_volt) / r->step);
+			ret = 0;
+		} else {
+			*sel = r->min_sel;
+			ret = 0;
+		}
+	}
+	return ret;
+}
+
+static int bd71837_get_enable(struct udevice *dev)
+{
+	int val;
+	struct bd71837_platdata *plat = dev_get_platdata(dev);
+
+	/*
+	 * boot critical regulators on bd71837 must not be controlled by sw
+	 * due to the 'feature' which leaves power rails down if bd71837 is
+	 * reseted to snvs state. hence we can't get the state here.
+	 *
+	 * if we are alive it means we probably are on run state and
+	 * if the regulator can't be controlled we can assume it is
+	 * enabled.
+	 */
+	if (plat->enablemask == HW_STATE_CONTROL)
+		return 1;
+
+	val = pmic_reg_read(dev->parent, plat->enable_reg);
+	if (val < 0)
+		return val;
+
+	return (val & plat->enablemask);
+}
+
+static int bd71837_set_enable(struct udevice *dev, bool enable)
+{
+	int val = 0;
+	struct bd71837_platdata *plat = dev_get_platdata(dev);
+
+	/*
+	 * boot critical regulators on bd71837 must not be controlled by sw
+	 * due to the 'feature' which leaves power rails down if bd71837 is
+	 * reseted to snvs state. Hence we can't set the state here.
+	 */
+	if (plat->enablemask == HW_STATE_CONTROL)
+		return -EINVAL;
+
+	if (enable)
+		val = plat->enablemask;
+
+	return pmic_clrsetbits(dev->parent, plat->enable_reg, plat->enablemask,
+			       val);
+}
+
+static int bd71837_set_value(struct udevice *dev, int uvolt)
+{
+	unsigned int sel;
+	unsigned int range;
+	int i;
+	int found = 0;
+	struct bd71837_platdata *plat = dev_get_platdata(dev);
+
+	/*
+	 * An under/overshooting may occur if voltage is changed for other
+	 * regulators but buck 1,2,3 or 4 when regulator is enabled. Prevent
+	 * change to protect the HW
+	 */
+	if (!plat->dvs)
+		if (bd71837_get_enable(dev)) {
+			pr_err("Only DVS bucks can be changed when enabled\n");
+			return -EINVAL;
+		}
+
+	for (i = 0; i < plat->numranges; i++) {
+		struct bd71837_vrange *r = &plat->ranges[i];
+
+		found = !vrange_find_selector(r, uvolt, &sel);
+		if (found) {
+			unsigned int tmp;
+
+			/*
+			 * We require exactly the requested value to be
+			 * supported - this can be changed later if needed
+			 */
+			range = r->rangeval;
+			found = !vrange_find_value(r, sel, &tmp);
+			if (found && tmp == uvolt)
+				break;
+			found = 0;
+		}
+	}
+
+	if (!found)
+		return -EINVAL;
+
+	sel <<= ffs(plat->volt_mask) - 1;
+
+	if (plat->rangemask)
+		sel |= range;
+
+	return pmic_clrsetbits(dev->parent, plat->volt_reg, plat->volt_mask |
+			       plat->rangemask, sel);
+}
+
+static int bd71837_get_value(struct udevice *dev)
+{
+	unsigned int reg, range;
+	unsigned int tmp;
+	struct bd71837_platdata *plat = dev_get_platdata(dev);
+	int i;
+
+	reg = pmic_reg_read(dev->parent, plat->volt_reg);
+	if (((int)reg) < 0)
+		return reg;
+
+	range = reg & plat->rangemask;
+
+	reg &= plat->volt_mask;
+	reg >>= ffs(plat->volt_mask) - 1;
+
+	for (i = 0; i < plat->numranges; i++) {
+		struct bd71837_vrange *r = &plat->ranges[i];
+
+		if (plat->rangemask && ((plat->rangemask & range) !=
+		    r->rangeval))
+			continue;
+
+		if (!vrange_find_value(r, reg, &tmp))
+			return tmp;
+	}
+
+	pr_err("Unknown voltage value read from pmic\n");
+
+	return -EINVAL;
+}
+
+static int bd71837_regulator_probe(struct udevice *dev)
+{
+	struct bd71837_platdata *plat = dev_get_platdata(dev);
+	int i, ret;
+	struct dm_regulator_uclass_platdata *uc_pdata;
+	int type;
+	struct bd71837_platdata *init_data;
+	int data_amnt;
+
+	type = dev_get_driver_data(dev_get_parent(dev));
+
+	switch (type) {
+	case ROHM_CHIP_TYPE_BD71837:
+		init_data = bd71837_reg_data;
+		data_amnt = ARRAY_SIZE(bd71837_reg_data);
+		break;
+	case ROHM_CHIP_TYPE_BD71847:
+		init_data = bd71847_reg_data;
+		data_amnt = ARRAY_SIZE(bd71847_reg_data);
+		break;
+	default:
+		debug("Unknown PMIC type\n");
+		init_data = NULL;
+		data_amnt = 0;
+		break;
+	}
+
+	for (i = 0; i < data_amnt; i++) {
+		if (!strcmp(dev->name, init_data[i].name)) {
+			*plat = init_data[i];
+			if (plat->enablemask != HW_STATE_CONTROL) {
+				/*
+				 * Take the regulator under SW control. Ensure
+				 * the initial state matches dt flags and then
+				 * write the SEL bit
+				 */
+				uc_pdata = dev_get_uclass_platdata(dev);
+				ret = bd71837_set_enable(dev,
+							 !!(uc_pdata->boot_on ||
+							 uc_pdata->always_on));
+				if (ret)
+					return ret;
+
+				return pmic_clrsetbits(dev->parent,
+						      plat->enable_reg,
+						      plat->sel_mask,
+						      plat->sel_mask);
+			}
+			return 0;
+		}
+	}
+
+	pr_err("Unknown regulator '%s'\n", dev->name);
+
+	return -ENOENT;
+}
+
+static const struct dm_regulator_ops bd71837_regulator_ops = {
+	.get_value  = bd71837_get_value,
+	.set_value  = bd71837_set_value,
+	.get_enable = bd71837_get_enable,
+	.set_enable = bd71837_set_enable,
+};
+
+U_BOOT_DRIVER(bd71837_regulator) = {
+	.name = BD718XX_REGULATOR_DRIVER,
+	.id = UCLASS_REGULATOR,
+	.ops = &bd71837_regulator_ops,
+	.probe = bd71837_regulator_probe,
+	.platdata_auto_alloc_size = sizeof(struct bd71837_platdata),
+};