[v4,5/7] regulator: mt6392: Add support for MT6392 regulator
diff mbox series

Message ID 20190619142013.20913-6-fparent@baylibre.com
State New
Headers show
Series
  • mt6392: Add support for MediaTek MT6392 PMIC
Related show

Commit Message

Fabien Parent June 19, 2019, 2:20 p.m. UTC
The MT6392 is a regulator found on boards based on the MediaTek
MT8167, MT8516, and probably other SoCs. It is a so called PMIC and
connectcts as a slave to a SoC using SPI, wrapped inside PWRAP.

Signed-off-by: Fabien Parent <fparent@baylibre.com>
---

V4:
	* No change

V3:
	* fix regulator's of_match following the renaming of the of nodes.

V2:
	* no changes

---
 drivers/regulator/Kconfig                  |   9 +
 drivers/regulator/Makefile                 |   1 +
 drivers/regulator/mt6392-regulator.c       | 490 +++++++++++++++++++++
 include/linux/regulator/mt6392-regulator.h |  40 ++
 4 files changed, 540 insertions(+)
 create mode 100644 drivers/regulator/mt6392-regulator.c
 create mode 100644 include/linux/regulator/mt6392-regulator.h

Comments

Mark Brown June 19, 2019, 5:23 p.m. UTC | #1
On Wed, Jun 19, 2019 at 04:20:11PM +0200, Fabien Parent wrote:

> connectcts as a slave to a SoC using SPI, wrapped inside PWRAP.
> 
> Signed-off-by: Fabien Parent <fparent@baylibre.com>

This has your signoff...

> +++ b/drivers/regulator/mt6392-regulator.c
> @@ -0,0 +1,490 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (c) 2019 MediaTek Inc.
> + * Author: Chen Zhong <chen.zhong@mediatek.com>
> + */

...but someone else from a different company wrote it?  Also please make
the entire header a C++ one so this looks more consistent.

> +static const u32 ldo_volt_table2[] = {
> +	3300000, 3400000, 3500000, 3600000,
> +};

This looks like a linear range?

> +static int mt6392_get_status(struct regulator_dev *rdev)
> +{
> +	int ret;
> +	u32 regval;
> +	struct mt6392_regulator_info *info = rdev_get_drvdata(rdev);
> +
> +	ret = regmap_read(rdev->regmap, info->desc.enable_reg, &regval);
> +	if (ret != 0) {
> +		dev_err(&rdev->dev, "Failed to get enable reg: %d\n", ret);
> +		return ret;
> +	}
> +
> +	return (regval & info->qi) ? REGULATOR_STATUS_ON : REGULATOR_STATUS_OFF;
> +}

This appears to just be reading back the enable bit, the status
operation should only be implemented if it can check if the regulator
is actually working.

Please also don't use the ternery operator needlessly, just write normal
conditional statements to help people read the code.

> +static int mt6392_buck_set_mode(struct regulator_dev *rdev, unsigned int mode)
> +{
> +	int ret, val = 0;
> +	struct mt6392_regulator_info *info = rdev_get_drvdata(rdev);
> +	u32 reg_value;
> +
> +	if (!info->modeset_mask) {
> +		dev_err(&rdev->dev, "regulator %s doesn't support set_mode\n",
> +			info->desc.name);
> +		return -EINVAL;
> +	}

If a regulator doesn't have support for set_mode() the operation
shouldn't be provided for it.

> +	ret = regmap_update_bits(rdev->regmap, info->modeset_reg,
> +				  info->modeset_mask, val);
> +
> +	if (regmap_read(rdev->regmap, info->modeset_reg, &reg_value) < 0) {
> +		dev_err(&rdev->dev, "Failed to read register value\n");
> +		return -EIO;
> +	}

Why are we doing this read?  It's not like anything even looks at the
value.

> +static int mt6392_set_buck_vosel_reg(struct platform_device *pdev)
> +{
> +	struct mt6397_chip *mt6392 = dev_get_drvdata(pdev->dev.parent);
> +	int i;
> +	u32 regval;
> +
> +	for (i = 0; i < MT6392_MAX_REGULATOR; i++) {
> +		if (mt6392_regulators[i].vselctrl_reg) {
> +			if (regmap_read(mt6392->regmap,
> +				mt6392_regulators[i].vselctrl_reg,
> +				&regval) < 0) {
> +				dev_err(&pdev->dev,
> +					"Failed to read buck ctrl\n");
> +				return -EIO;
> +			}

The indentation here is seriously messed up, parts of the conditional
statement are indented as far as the code block inside the conditional
statement - usually the continuation of the condition would align with
the (.

> +
> +			if (regval & mt6392_regulators[i].vselctrl_mask) {
> +				mt6392_regulators[i].desc.vsel_reg =
> +				mt6392_regulators[i].vselon_reg;
> +			}

Again here the indentation is weird, this is actually one statement in
the { } but the second line isn't indented.

I'm also not altogether clear why this function is doing what it's
doing, some comments or something would be good at least.

> +		/* Constrain board-specific capabilities according to what
> +		 * this driver and the chip itself can actually do.
> +		 */
> +		c = rdev->constraints;
> +		c->valid_modes_mask |= REGULATOR_MODE_NORMAL|
> +			REGULATOR_MODE_STANDBY | REGULATOR_MODE_FAST;
> +		c->valid_ops_mask |= REGULATOR_CHANGE_MODE;

This is broken, the driver should absolutely not modify constraints.
The driver isn't even doing what the comment says here, it's enabling
permissions regardless of if they were enabled by the machine.

> +static const struct of_device_id mt6392_of_match[] = {
> +	{ .compatible = "mediatek,mt6392-regulator", },
> +	{ /* sentinel */ },
> +};
> +MODULE_DEVICE_TABLE(of, mt6392_of_match);

There is no need for a compatible for this subfunction, it's specific to
a single chip so we should be able to enumerate it just by enumerating
that chip and this way of binding regulators is very Linux specific.
Just have the MFD register the regulator device.

Patch
diff mbox series

diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 8553bdf87c1d..6f6865b95c36 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -626,6 +626,15 @@  config REGULATOR_MT6380
 	  This driver supports the control of different power rails of device
 	  through regulator interface.
 
+config REGULATOR_MT6392
+	tristate "MediaTek MT6392 PMIC"
+	depends on MFD_MT6397
+	help
+	  Say y here to select this option to enable the power regulator of
+	  MediaTek MT6392 PMIC.
+	  This driver supports the control of different power rails of device
+	  through regulator interface.
+
 config REGULATOR_MT6397
 	tristate "MediaTek MT6397 PMIC"
 	depends on MFD_MT6397
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index 93f53840e8f1..fc67a215479d 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -80,6 +80,7 @@  obj-$(CONFIG_REGULATOR_MCP16502) += mcp16502.o
 obj-$(CONFIG_REGULATOR_MT6311) += mt6311-regulator.o
 obj-$(CONFIG_REGULATOR_MT6323)	+= mt6323-regulator.o
 obj-$(CONFIG_REGULATOR_MT6380)	+= mt6380-regulator.o
+obj-$(CONFIG_REGULATOR_MT6392)	+= mt6392-regulator.o
 obj-$(CONFIG_REGULATOR_MT6397)	+= mt6397-regulator.o
 obj-$(CONFIG_REGULATOR_QCOM_RPM) += qcom_rpm-regulator.o
 obj-$(CONFIG_REGULATOR_QCOM_RPMH) += qcom-rpmh-regulator.o
diff --git a/drivers/regulator/mt6392-regulator.c b/drivers/regulator/mt6392-regulator.c
new file mode 100644
index 000000000000..2b7dcf3c72e8
--- /dev/null
+++ b/drivers/regulator/mt6392-regulator.c
@@ -0,0 +1,490 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2019 MediaTek Inc.
+ * Author: Chen Zhong <chen.zhong@mediatek.com>
+ */
+
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/mfd/mt6397/core.h>
+#include <linux/mfd/mt6392/registers.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+#include <linux/regulator/mt6392-regulator.h>
+#include <linux/regulator/of_regulator.h>
+
+#define MT6392_BUCK_MODE_AUTO	0
+#define MT6392_BUCK_MODE_FORCE_PWM	1
+#define MT6392_LDO_MODE_NORMAL	0
+#define MT6392_LDO_MODE_LP	1
+
+/*
+ * MT6392 regulators' information
+ *
+ * @desc: standard fields of regulator description.
+ * @qi: Mask for query enable signal status of regulators
+ * @vselon_reg: Register sections for hardware control mode of bucks
+ * @vselctrl_reg: Register for controlling the buck control mode.
+ * @vselctrl_mask: Mask for query buck's voltage control mode.
+ */
+struct mt6392_regulator_info {
+	struct regulator_desc desc;
+	u32 qi;
+	u32 vselon_reg;
+	u32 vselctrl_reg;
+	u32 vselctrl_mask;
+	u32 modeset_reg;
+	u32 modeset_mask;
+};
+
+#define MT6392_BUCK(match, vreg, min, max, step, volt_ranges, enreg,	\
+		vosel, vosel_mask, voselon, vosel_ctrl,			\
+		_modeset_reg, _modeset_mask)				\
+[MT6392_ID_##vreg] = {							\
+	.desc = {							\
+		.name = #vreg,						\
+		.of_match = of_match_ptr(match),			\
+		.ops = &mt6392_volt_range_ops,				\
+		.type = REGULATOR_VOLTAGE,				\
+		.id = MT6392_ID_##vreg,					\
+		.owner = THIS_MODULE,					\
+		.n_voltages = (max - min)/step + 1,			\
+		.linear_ranges = volt_ranges,				\
+		.n_linear_ranges = ARRAY_SIZE(volt_ranges),		\
+		.vsel_reg = vosel,					\
+		.vsel_mask = vosel_mask,				\
+		.enable_reg = enreg,					\
+		.enable_mask = BIT(0),					\
+	},								\
+	.qi = BIT(13),							\
+	.vselon_reg = voselon,						\
+	.vselctrl_reg = vosel_ctrl,					\
+	.vselctrl_mask = BIT(1),					\
+	.modeset_reg = _modeset_reg,					\
+	.modeset_mask = _modeset_mask,					\
+}
+
+#define MT6392_LDO(match, vreg, ldo_volt_table, enreg, enbit, vosel,	\
+		vosel_mask, _modeset_reg, _modeset_mask)		\
+[MT6392_ID_##vreg] = {							\
+	.desc = {							\
+		.name = #vreg,						\
+		.of_match = of_match_ptr(match),			\
+		.ops = &mt6392_volt_table_ops,				\
+		.type = REGULATOR_VOLTAGE,				\
+		.id = MT6392_ID_##vreg,					\
+		.owner = THIS_MODULE,					\
+		.n_voltages = ARRAY_SIZE(ldo_volt_table),		\
+		.volt_table = ldo_volt_table,				\
+		.vsel_reg = vosel,					\
+		.vsel_mask = vosel_mask,				\
+		.enable_reg = enreg,					\
+		.enable_mask = BIT(enbit),				\
+	},								\
+	.qi = BIT(15),							\
+	.modeset_reg = _modeset_reg,					\
+	.modeset_mask = _modeset_mask,					\
+}
+
+#define MT6392_REG_FIXED(match, vreg, enreg, enbit, volt,		\
+		_modeset_reg, _modeset_mask)				\
+[MT6392_ID_##vreg] = {							\
+	.desc = {							\
+		.name = #vreg,						\
+		.of_match = of_match_ptr(match),			\
+		.ops = &mt6392_volt_fixed_ops,				\
+		.type = REGULATOR_VOLTAGE,				\
+		.id = MT6392_ID_##vreg,					\
+		.owner = THIS_MODULE,					\
+		.n_voltages = 1,					\
+		.enable_reg = enreg,					\
+		.enable_mask = BIT(enbit),				\
+		.min_uV = volt,						\
+	},								\
+	.qi = BIT(15),							\
+	.modeset_reg = _modeset_reg,					\
+	.modeset_mask = _modeset_mask,					\
+}
+
+static const struct regulator_linear_range buck_volt_range1[] = {
+	REGULATOR_LINEAR_RANGE(700000, 0, 0x7f, 6250),
+};
+
+static const struct regulator_linear_range buck_volt_range2[] = {
+	REGULATOR_LINEAR_RANGE(1400000, 0, 0x7f, 12500),
+};
+
+static const u32 ldo_volt_table1[] = {
+	1800000, 1900000, 2000000, 2200000,
+};
+
+static const u32 ldo_volt_table2[] = {
+	3300000, 3400000, 3500000, 3600000,
+};
+
+static const u32 ldo_volt_table3[] = {
+	1800000, 3300000,
+};
+
+static const u32 ldo_volt_table4[] = {
+	3000000, 3300000,
+};
+
+static const u32 ldo_volt_table5[] = {
+	1200000, 1300000, 1500000, 1800000, 2000000, 2800000, 3000000, 3300000,
+};
+
+static const u32 ldo_volt_table6[] = {
+	1240000, 1390000,
+};
+
+static const u32 ldo_volt_table7[] = {
+	1200000, 1300000, 1500000, 1800000,
+};
+
+static const u32 ldo_volt_table8[] = {
+	1800000, 2000000,
+};
+
+static int mt6392_get_status(struct regulator_dev *rdev)
+{
+	int ret;
+	u32 regval;
+	struct mt6392_regulator_info *info = rdev_get_drvdata(rdev);
+
+	ret = regmap_read(rdev->regmap, info->desc.enable_reg, &regval);
+	if (ret != 0) {
+		dev_err(&rdev->dev, "Failed to get enable reg: %d\n", ret);
+		return ret;
+	}
+
+	return (regval & info->qi) ? REGULATOR_STATUS_ON : REGULATOR_STATUS_OFF;
+}
+
+static int mt6392_buck_set_mode(struct regulator_dev *rdev, unsigned int mode)
+{
+	int ret, val = 0;
+	struct mt6392_regulator_info *info = rdev_get_drvdata(rdev);
+	u32 reg_value;
+
+	if (!info->modeset_mask) {
+		dev_err(&rdev->dev, "regulator %s doesn't support set_mode\n",
+			info->desc.name);
+		return -EINVAL;
+	}
+
+	switch (mode) {
+	case REGULATOR_MODE_FAST:
+		val = MT6392_BUCK_MODE_FORCE_PWM;
+		break;
+	case REGULATOR_MODE_NORMAL:
+		val = MT6392_BUCK_MODE_AUTO;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	val <<= ffs(info->modeset_mask) - 1;
+
+	ret = regmap_update_bits(rdev->regmap, info->modeset_reg,
+				  info->modeset_mask, val);
+
+	if (regmap_read(rdev->regmap, info->modeset_reg, &reg_value) < 0) {
+		dev_err(&rdev->dev, "Failed to read register value\n");
+		return -EIO;
+	}
+
+	return ret;
+}
+
+static unsigned int mt6392_buck_get_mode(struct regulator_dev *rdev)
+{
+	unsigned int val;
+	unsigned int mode;
+	int ret;
+	struct mt6392_regulator_info *info = rdev_get_drvdata(rdev);
+
+	if (!info->modeset_mask) {
+		dev_err(&rdev->dev, "regulator %s doesn't support get_mode\n",
+			info->desc.name);
+		return -EINVAL;
+	}
+
+	ret = regmap_read(rdev->regmap, info->modeset_reg, &val);
+	if (ret < 0)
+		return ret;
+
+	val &= info->modeset_mask;
+	val >>= ffs(info->modeset_mask) - 1;
+
+	if (val & 0x1)
+		mode = REGULATOR_MODE_FAST;
+	else
+		mode = REGULATOR_MODE_NORMAL;
+
+	return mode;
+}
+
+static int mt6392_ldo_set_mode(struct regulator_dev *rdev, unsigned int mode)
+{
+	int ret, val = 0;
+	struct mt6392_regulator_info *info = rdev_get_drvdata(rdev);
+
+	if (!info->modeset_mask) {
+		dev_err(&rdev->dev, "regulator %s doesn't support set_mode\n",
+			info->desc.name);
+		return -EINVAL;
+	}
+
+	switch (mode) {
+	case REGULATOR_MODE_STANDBY:
+		val = MT6392_LDO_MODE_LP;
+		break;
+	case REGULATOR_MODE_NORMAL:
+		val = MT6392_LDO_MODE_NORMAL;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	val <<= ffs(info->modeset_mask) - 1;
+
+	ret = regmap_update_bits(rdev->regmap, info->modeset_reg,
+				  info->modeset_mask, val);
+
+	return ret;
+}
+
+static unsigned int mt6392_ldo_get_mode(struct regulator_dev *rdev)
+{
+	unsigned int val;
+	unsigned int mode;
+	int ret;
+	struct mt6392_regulator_info *info = rdev_get_drvdata(rdev);
+
+	if (!info->modeset_mask) {
+		dev_err(&rdev->dev, "regulator %s doesn't support get_mode\n",
+			info->desc.name);
+		return -EINVAL;
+	}
+
+	ret = regmap_read(rdev->regmap, info->modeset_reg, &val);
+	if (ret < 0)
+		return ret;
+
+	val &= info->modeset_mask;
+	val >>= ffs(info->modeset_mask) - 1;
+
+	if (val & 0x1)
+		mode = REGULATOR_MODE_STANDBY;
+	else
+		mode = REGULATOR_MODE_NORMAL;
+
+	return mode;
+}
+
+static const struct regulator_ops mt6392_volt_range_ops = {
+	.list_voltage = regulator_list_voltage_linear_range,
+	.map_voltage = regulator_map_voltage_linear_range,
+	.set_voltage_sel = regulator_set_voltage_sel_regmap,
+	.get_voltage_sel = regulator_get_voltage_sel_regmap,
+	.set_voltage_time_sel = regulator_set_voltage_time_sel,
+	.enable = regulator_enable_regmap,
+	.disable = regulator_disable_regmap,
+	.is_enabled = regulator_is_enabled_regmap,
+	.get_status = mt6392_get_status,
+	.set_mode = mt6392_buck_set_mode,
+	.get_mode = mt6392_buck_get_mode,
+};
+
+static const struct regulator_ops mt6392_volt_table_ops = {
+	.list_voltage = regulator_list_voltage_table,
+	.map_voltage = regulator_map_voltage_iterate,
+	.set_voltage_sel = regulator_set_voltage_sel_regmap,
+	.get_voltage_sel = regulator_get_voltage_sel_regmap,
+	.set_voltage_time_sel = regulator_set_voltage_time_sel,
+	.enable = regulator_enable_regmap,
+	.disable = regulator_disable_regmap,
+	.is_enabled = regulator_is_enabled_regmap,
+	.get_status = mt6392_get_status,
+	.set_mode = mt6392_ldo_set_mode,
+	.get_mode = mt6392_ldo_get_mode,
+};
+
+static const struct regulator_ops mt6392_volt_fixed_ops = {
+	.list_voltage = regulator_list_voltage_linear,
+	.enable = regulator_enable_regmap,
+	.disable = regulator_disable_regmap,
+	.is_enabled = regulator_is_enabled_regmap,
+	.get_status = mt6392_get_status,
+	.set_mode = mt6392_ldo_set_mode,
+	.get_mode = mt6392_ldo_get_mode,
+};
+
+/* The array is indexed by id(MT6392_ID_XXX) */
+static struct mt6392_regulator_info mt6392_regulators[] = {
+	MT6392_BUCK("buck-vproc", VPROC, 700000, 1493750, 6250,
+		buck_volt_range1, MT6392_VPROC_CON7, MT6392_VPROC_CON9, 0x7f,
+		MT6392_VPROC_CON10, MT6392_VPROC_CON5, MT6392_VPROC_CON2,
+		0x100),
+	MT6392_BUCK("buck-vsys", VSYS, 1400000, 2987500, 12500,
+		buck_volt_range2, MT6392_VSYS_CON7, MT6392_VSYS_CON9, 0x7f,
+		MT6392_VSYS_CON10, MT6392_VSYS_CON5, MT6392_VSYS_CON2, 0x100),
+	MT6392_BUCK("buck-vcore", VCORE, 700000, 1493750, 6250,
+		buck_volt_range1, MT6392_VCORE_CON7, MT6392_VCORE_CON9, 0x7f,
+		MT6392_VCORE_CON10, MT6392_VCORE_CON5, MT6392_VCORE_CON2,
+		0x100),
+	MT6392_REG_FIXED("ldo-vxo22", VXO22, MT6392_ANALDO_CON1, 10, 2200000,
+		MT6392_ANALDO_CON1, 0x2),
+	MT6392_LDO("ldo-vaud22", VAUD22, ldo_volt_table1,
+		MT6392_ANALDO_CON2, 14, MT6392_ANALDO_CON8, 0x60,
+		MT6392_ANALDO_CON2, 0x2),
+	MT6392_REG_FIXED("ldo-vcama", VCAMA, MT6392_ANALDO_CON4, 15, 2800000,
+		-1, 0),
+	MT6392_REG_FIXED("ldo-vaud28", VAUD28, MT6392_ANALDO_CON23, 14, 2800000,
+		MT6392_ANALDO_CON23, 0x2),
+	MT6392_REG_FIXED("ldo-vadc18", VADC18, MT6392_ANALDO_CON25, 14, 1800000,
+		MT6392_ANALDO_CON25, 0x2),
+	MT6392_LDO("ldo-vcn35", VCN35, ldo_volt_table2,
+		MT6392_ANALDO_CON21, 12, MT6392_ANALDO_CON16, 0xC,
+		MT6392_ANALDO_CON21, 0x2),
+	MT6392_REG_FIXED("ldo-vio28", VIO28, MT6392_DIGLDO_CON0, 14, 2800000,
+		MT6392_DIGLDO_CON0, 0x2),
+	MT6392_REG_FIXED("ldo-vusb", VUSB, MT6392_DIGLDO_CON2, 14, 3300000,
+		MT6392_DIGLDO_CON2, 0x2),
+	MT6392_LDO("ldo-vmc", VMC, ldo_volt_table3,
+		MT6392_DIGLDO_CON3, 12, MT6392_DIGLDO_CON24, 0x10,
+		MT6392_DIGLDO_CON3, 0x2),
+	MT6392_LDO("ldo-vmch", VMCH, ldo_volt_table4,
+		MT6392_DIGLDO_CON5, 14, MT6392_DIGLDO_CON26, 0x80,
+		MT6392_DIGLDO_CON5, 0x2),
+	MT6392_LDO("ldo-vemc3v3", VEMC3V3, ldo_volt_table4,
+		MT6392_DIGLDO_CON6, 14, MT6392_DIGLDO_CON27, 0x80,
+		MT6392_DIGLDO_CON6, 0x2),
+	MT6392_LDO("ldo-vgp1", VGP1, ldo_volt_table5,
+		MT6392_DIGLDO_CON7, 15, MT6392_DIGLDO_CON28, 0xE0,
+		MT6392_DIGLDO_CON7, 0x2),
+	MT6392_LDO("ldo-vgp2", VGP2, ldo_volt_table5,
+		MT6392_DIGLDO_CON8, 15, MT6392_DIGLDO_CON29, 0xE0,
+		MT6392_DIGLDO_CON8, 0x2),
+	MT6392_REG_FIXED("ldo-vcn18", VCN18, MT6392_DIGLDO_CON11, 14, 1800000,
+		MT6392_DIGLDO_CON11, 0x2),
+	MT6392_LDO("ldo-vcamaf", VCAMAF, ldo_volt_table5,
+		MT6392_DIGLDO_CON31, 15, MT6392_DIGLDO_CON32, 0xE0,
+		MT6392_DIGLDO_CON31, 0x2),
+	MT6392_LDO("ldo-vm", VM, ldo_volt_table6,
+		MT6392_DIGLDO_CON47, 14, MT6392_DIGLDO_CON48, 0x30,
+		MT6392_DIGLDO_CON47, 0x2),
+	MT6392_REG_FIXED("ldo-vio18", VIO18, MT6392_DIGLDO_CON49, 14, 1800000,
+		MT6392_DIGLDO_CON49, 0x2),
+	MT6392_LDO("ldo-vcamd", VCAMD, ldo_volt_table7,
+		MT6392_DIGLDO_CON51, 14, MT6392_DIGLDO_CON52, 0x60,
+		MT6392_DIGLDO_CON51, 0x2),
+	MT6392_REG_FIXED("ldo-vcamio", VCAMIO, MT6392_DIGLDO_CON53, 14, 1800000,
+		MT6392_DIGLDO_CON53, 0x2),
+	MT6392_REG_FIXED("ldo-vm25", VM25, MT6392_DIGLDO_CON55, 14, 2500000,
+		MT6392_DIGLDO_CON55, 0x2),
+	MT6392_LDO("ldo-vefuse", VEFUSE, ldo_volt_table8,
+		MT6392_DIGLDO_CON57, 14, MT6392_DIGLDO_CON58, 0x10,
+		MT6392_DIGLDO_CON57, 0x2),
+};
+
+static int mt6392_set_buck_vosel_reg(struct platform_device *pdev)
+{
+	struct mt6397_chip *mt6392 = dev_get_drvdata(pdev->dev.parent);
+	int i;
+	u32 regval;
+
+	for (i = 0; i < MT6392_MAX_REGULATOR; i++) {
+		if (mt6392_regulators[i].vselctrl_reg) {
+			if (regmap_read(mt6392->regmap,
+				mt6392_regulators[i].vselctrl_reg,
+				&regval) < 0) {
+				dev_err(&pdev->dev,
+					"Failed to read buck ctrl\n");
+				return -EIO;
+			}
+
+			if (regval & mt6392_regulators[i].vselctrl_mask) {
+				mt6392_regulators[i].desc.vsel_reg =
+				mt6392_regulators[i].vselon_reg;
+			}
+		}
+	}
+
+	return 0;
+}
+
+static int mt6392_regulator_probe(struct platform_device *pdev)
+{
+	struct mt6397_chip *mt6392 = dev_get_drvdata(pdev->dev.parent);
+	struct regulator_config config = {};
+	struct regulator_dev *rdev;
+	struct regulation_constraints *c;
+	int i;
+	u32 reg_value;
+
+	/* Query buck controller to select activated voltage register part */
+	if (mt6392_set_buck_vosel_reg(pdev))
+		return -EIO;
+
+	/* Read PMIC chip revision to update constraints and voltage table */
+	if (regmap_read(mt6392->regmap, MT6392_CID, &reg_value) < 0) {
+		dev_err(&pdev->dev, "Failed to read Chip ID\n");
+		return -EIO;
+	}
+
+	dev_info(&pdev->dev, "Chip ID = 0x%x\n", reg_value);
+
+	for (i = 0; i < MT6392_MAX_REGULATOR; i++) {
+		config.dev = &pdev->dev;
+		config.driver_data = &mt6392_regulators[i];
+		config.regmap = mt6392->regmap;
+		rdev = devm_regulator_register(&pdev->dev,
+				&mt6392_regulators[i].desc, &config);
+		if (IS_ERR(rdev)) {
+			dev_err(&pdev->dev, "failed to register %s\n",
+				mt6392_regulators[i].desc.name);
+			return PTR_ERR(rdev);
+		}
+
+		/* Constrain board-specific capabilities according to what
+		 * this driver and the chip itself can actually do.
+		 */
+		c = rdev->constraints;
+		c->valid_modes_mask |= REGULATOR_MODE_NORMAL|
+			REGULATOR_MODE_STANDBY | REGULATOR_MODE_FAST;
+		c->valid_ops_mask |= REGULATOR_CHANGE_MODE;
+
+	}
+	return 0;
+}
+
+static const struct platform_device_id mt6392_platform_ids[] = {
+	{"mt6392-regulator", 0},
+	{ /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(platform, mt6392_platform_ids);
+
+static const struct of_device_id mt6392_of_match[] = {
+	{ .compatible = "mediatek,mt6392-regulator", },
+	{ /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, mt6392_of_match);
+
+static struct platform_driver mt6392_regulator_driver = {
+	.driver = {
+		.name = "mt6392-regulator",
+		.of_match_table = of_match_ptr(mt6392_of_match),
+	},
+	.probe = mt6392_regulator_probe,
+	.id_table = mt6392_platform_ids,
+};
+
+module_platform_driver(mt6392_regulator_driver);
+
+MODULE_AUTHOR("Chen Zhong <chen.zhong@mediatek.com>");
+MODULE_DESCRIPTION("Regulator Driver for MediaTek MT6392 PMIC");
+MODULE_LICENSE("GPL v2");
diff --git a/include/linux/regulator/mt6392-regulator.h b/include/linux/regulator/mt6392-regulator.h
new file mode 100644
index 000000000000..dfcbcacb5ad4
--- /dev/null
+++ b/include/linux/regulator/mt6392-regulator.h
@@ -0,0 +1,40 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2019 MediaTek Inc.
+ * Author: Chen Zhong <chen.zhong@mediatek.com>
+ */
+
+#ifndef __LINUX_REGULATOR_MT6392_H
+#define __LINUX_REGULATOR_MT6392_H
+
+enum {
+	MT6392_ID_VPROC = 0,
+	MT6392_ID_VSYS,
+	MT6392_ID_VCORE,
+	MT6392_ID_VXO22,
+	MT6392_ID_VAUD22,
+	MT6392_ID_VCAMA,
+	MT6392_ID_VAUD28,
+	MT6392_ID_VADC18,
+	MT6392_ID_VCN35,
+	MT6392_ID_VIO28,
+	MT6392_ID_VUSB = 10,
+	MT6392_ID_VMC,
+	MT6392_ID_VMCH,
+	MT6392_ID_VEMC3V3,
+	MT6392_ID_VGP1,
+	MT6392_ID_VGP2,
+	MT6392_ID_VCN18,
+	MT6392_ID_VCAMAF,
+	MT6392_ID_VM,
+	MT6392_ID_VIO18,
+	MT6392_ID_VCAMD,
+	MT6392_ID_VCAMIO,
+	MT6392_ID_VM25,
+	MT6392_ID_VEFUSE,
+	MT6392_ID_RG_MAX,
+};
+
+#define MT6392_MAX_REGULATOR	MT6392_ID_RG_MAX
+
+#endif /* __LINUX_REGULATOR_MT6392_H */