regulator: Add rt8092 support

RT8092 is a 3MHz 4A efficiency step-down converter with I2C control
interface. It can support wide output range from 0.7 to 5.5V, based on
the voltage bank selection.

Signed-off-by: ChiYuan Huang <cy_huang@richtek.com>
Link: https://patch.msgid.link/d2293c513f396f86e54f9b806fd0195b57db7aae.1766125676.git.cy_huang@richtek.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: ChiYuan Huang

drivers/regulator/Kconfig

@@ -1394,6 +1394,15 @@ config REGULATOR_RT6245
 	  It can support up to 14A output current and adjustable output voltage
 	  from 0.4375V to 1.3875V, per step 12.5mV.
 
+config REGULATOR_RT8092
+	tristate "Richtek RT8092 voltage regulator"
+	depends on I2C
+	select REGMAP_I2C
+	help
+	  The RT8092 is a peak-current mode PWM step-down DC/DC converter with
+	  I2C control interface. It is capable of delivering 4A continuing
+	  current over a wide input range from 2.5V to 5.5V.
+
 config REGULATOR_RTQ2134
 	tristate "Richtek RTQ2134 SubPMIC Regulator"
 	depends on I2C

drivers/regulator/Makefile

@@ -161,6 +161,7 @@ obj-$(CONFIG_REGULATOR_RT5759)	+= rt5759-regulator.o
 obj-$(CONFIG_REGULATOR_RT6160)	+= rt6160-regulator.o
 obj-$(CONFIG_REGULATOR_RT6190)	+= rt6190-regulator.o
 obj-$(CONFIG_REGULATOR_RT6245)	+= rt6245-regulator.o
+obj-$(CONFIG_REGULATOR_RT8092)	+= rt8092.o
 obj-$(CONFIG_REGULATOR_RTMV20)	+= rtmv20-regulator.o
 obj-$(CONFIG_REGULATOR_RTQ2134) += rtq2134-regulator.o
 obj-$(CONFIG_REGULATOR_RTQ6752)	+= rtq6752-regulator.o

drivers/regulator/rt8092.c

@@ -0,0 +1,313 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+// Copyright (c) 2025 Richtek Technology Corp.
+//
+// Author: ChiYuan Huang <cy_huang@richtek.com>
+
+#include <linux/bitfield.h>
+#include <linux/bits.h>
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/property.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/of_regulator.h>
+
+#define RT8092_REG_MNTRPT	0x00
+#define RT8092_REG_VOUTH	0x10
+#define RT8092_REG_VOUTL	0x11
+#define RT8092_REG_PWMMODE	0x14
+#define RT8092_REG_EVENT	0x18
+#define RT8092_REG_VBANKH	0x1C
+#define RT8092_REG_VBANKL	0x1D
+#define RT8092_REG_VBOUND	0x1E
+
+#define RT8092_TSDEVT_MASK	BIT(7)
+#define RT8092_PGEVT_MASK	BIT(0)
+#define RT8092_VSEL_MASK	GENMASK(6, 0)
+#define RT8092_VOUTEN_MASK	BIT(7)
+#define RT8092_FPWML_MASK	BIT(7)
+#define RT8092_FPWMH_MASK	BIT(6)
+#define RT8092_OCPEVT_MASK	BIT(7)
+#define RT8092_SCPEVT_MASK	BIT(4)
+#define RT8092_VINUVEVT_MASK	BIT(1)
+#define RT8092_VBANK_MASK	GENMASK(1, 0)
+
+#define RT8092_MODE_AUTO	0
+#define RT8092_MODE_FPWM	1
+#define RT8092_VOUT_BASEUV	303125
+#define RT8092_VOUT_STEPUV	3125
+#define RT8092_VOUT_MINSEL	15
+#define RT8092_NUM_VOLTS	128
+#define RT8092_INITSS_US	400
+
+static int rt8092_get_vbank_index(struct regmap *regmap, bool vsel_high, unsigned int *vbank_idx)
+{
+	unsigned int vbank_reg = vsel_high ? RT8092_REG_VBANKH : RT8092_REG_VBANKL;
+	unsigned int index;
+	int ret;
+
+	ret = regmap_read(regmap, vbank_reg, &index);
+	if (ret)
+		return ret;
+
+	*vbank_idx = FIELD_GET(RT8092_VBANK_MASK, index);
+	return 0;
+}
+
+static int rt8092_set_operating_mode(struct regulator_dev *rdev, unsigned int mode)
+{
+	const struct regulator_desc *desc = rdev->desc;
+	struct regmap *regmap = rdev_get_regmap(rdev);
+	unsigned int mode_mask, mode_val;
+
+	mode_mask = desc->vsel_reg == RT8092_REG_VOUTH ? RT8092_FPWMH_MASK : RT8092_FPWML_MASK;
+
+	switch (mode) {
+	case REGULATOR_MODE_FAST:
+		mode_val = mode_mask;
+		break;
+	case REGULATOR_MODE_NORMAL:
+		mode_val = 0;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return regmap_update_bits(regmap, RT8092_REG_PWMMODE, mode_mask, mode_val);
+}
+
+static unsigned int rt8092_get_operating_mode(struct regulator_dev *rdev)
+{
+	const struct regulator_desc *desc = rdev->desc;
+	struct regmap *regmap = rdev_get_regmap(rdev);
+	unsigned int mode_mask, mode_val;
+	int ret;
+
+	mode_mask = desc->vsel_reg == RT8092_REG_VOUTH ? RT8092_FPWMH_MASK : RT8092_FPWML_MASK;
+
+	ret = regmap_read(regmap, RT8092_REG_PWMMODE, &mode_val);
+	if (ret)
+		return REGULATOR_MODE_INVALID;
+
+	return mode_val & mode_mask ? REGULATOR_MODE_FAST : REGULATOR_MODE_NORMAL;
+}
+
+static int rt8092_get_error_flags(struct regulator_dev *rdev, unsigned int *flags)
+{
+	struct regmap *regmap = rdev_get_regmap(rdev);
+	unsigned int mntrpt, evtrpt, events = 0;
+	int ret;
+
+	ret = regmap_read(regmap, RT8092_REG_MNTRPT, &mntrpt);
+	if (ret)
+		return ret;
+
+	ret = regmap_read(regmap, RT8092_REG_EVENT, &evtrpt);
+	if (ret)
+		return ret;
+
+	if (!(mntrpt & RT8092_PGEVT_MASK) || evtrpt & RT8092_VINUVEVT_MASK)
+		events |= REGULATOR_ERROR_UNDER_VOLTAGE;
+
+	if (mntrpt & RT8092_TSDEVT_MASK)
+		events |= REGULATOR_ERROR_OVER_TEMP;
+
+	if (evtrpt & RT8092_OCPEVT_MASK)
+		events |= REGULATOR_ERROR_OVER_CURRENT;
+
+	if (evtrpt & RT8092_SCPEVT_MASK)
+		events |= REGULATOR_ERROR_FAIL;
+
+	*flags = events;
+	return 0;
+}
+
+
+static int rt8092_set_suspend_voltage(struct regulator_dev *rdev, int uV)
+{
+	const struct regulator_desc *desc = rdev->desc;
+	struct regmap *regmap = rdev_get_regmap(rdev);
+	unsigned int vsel_reg, vsel_val, vbank_idx;
+	bool vsel_high;
+	int ret;
+
+	vsel_reg = desc->vsel_reg == RT8092_REG_VOUTH ? RT8092_REG_VOUTL : RT8092_REG_VOUTH;
+	vsel_high = desc->vsel_reg == RT8092_REG_VOUTH;
+
+	ret = rt8092_get_vbank_index(regmap, vsel_high, &vbank_idx);
+	if (ret)
+		return ret;
+
+	/* VOUT  = (BASEUV + STEPUV * VSEL) * 2^vbank_idx */
+	uV >>= vbank_idx;
+	if (uV < RT8092_VOUT_BASEUV)
+		return -EINVAL;
+
+	vsel_val = (uV - RT8092_VOUT_BASEUV) / RT8092_VOUT_STEPUV;
+	if (vsel_val < RT8092_VOUT_MINSEL || vsel_val >= RT8092_NUM_VOLTS)
+		return -EINVAL;
+
+	return regmap_update_bits(regmap, vsel_reg, RT8092_VSEL_MASK, vsel_val);
+}
+
+static int rt8092_set_suspend_enable(struct regulator_dev *rdev)
+{
+	const struct regulator_desc *desc = rdev->desc;
+	struct regmap *regmap = rdev_get_regmap(rdev);
+	unsigned int enable_reg;
+
+	enable_reg = desc->vsel_reg == RT8092_REG_VOUTH ? RT8092_REG_VOUTL : RT8092_REG_VOUTH;
+	return regmap_set_bits(regmap, enable_reg, RT8092_VOUTEN_MASK);
+}
+
+static int rt8092_set_suspend_disable(struct regulator_dev *rdev)
+{
+	const struct regulator_desc *desc = rdev->desc;
+	struct regmap *regmap = rdev_get_regmap(rdev);
+	unsigned int enable_reg;
+
+	enable_reg = desc->vsel_reg == RT8092_REG_VOUTH ? RT8092_REG_VOUTL : RT8092_REG_VOUTH;
+	return regmap_clear_bits(regmap, enable_reg, RT8092_VOUTEN_MASK);
+}
+
+static int rt8092_set_suspend_mode(struct regulator_dev *rdev, unsigned int mode)
+{
+	const struct regulator_desc *desc = rdev->desc;
+	struct regmap *regmap = rdev_get_regmap(rdev);
+	unsigned int mode_mask, mode_val;
+
+	mode_mask = desc->vsel_reg == RT8092_REG_VOUTH ? RT8092_FPWML_MASK : RT8092_FPWMH_MASK;
+
+	switch (mode) {
+	case REGULATOR_MODE_FAST:
+		mode_val = mode_mask;
+		break;
+	case REGULATOR_MODE_NORMAL:
+		mode_val = 0;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return regmap_update_bits(regmap, RT8092_REG_PWMMODE, mode_mask, mode_val);
+}
+
+static const struct regulator_ops rt8092_regulator_ops = {
+	.list_voltage = regulator_list_voltage_linear,
+	.get_voltage_sel = regulator_get_voltage_sel_regmap,
+	.set_voltage_sel = regulator_set_voltage_sel_regmap,
+	.enable = regulator_enable_regmap,
+	.disable = regulator_disable_regmap,
+	.is_enabled = regulator_is_enabled_regmap,
+	.set_mode = rt8092_set_operating_mode,
+	.get_mode = rt8092_get_operating_mode,
+	.get_error_flags = rt8092_get_error_flags,
+	.set_suspend_voltage = rt8092_set_suspend_voltage,
+	.set_suspend_enable = rt8092_set_suspend_enable,
+	.set_suspend_disable = rt8092_set_suspend_disable,
+	.set_suspend_mode = rt8092_set_suspend_mode,
+};
+
+static unsigned int rt8092_of_map_mode(unsigned int mode)
+{
+	switch (mode) {
+	case RT8092_MODE_AUTO:
+		return REGULATOR_MODE_NORMAL;
+	case RT8092_MODE_FPWM:
+		return REGULATOR_MODE_FAST;
+	default:
+		return REGULATOR_MODE_INVALID;
+	}
+}
+
+static const struct regmap_config rt8092_regmap_cfg = {
+	.name =	"rt8092",
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = RT8092_REG_VBOUND,
+};
+
+static int rt8092_probe(struct i2c_client *i2c)
+{
+	unsigned int vbank_idx, min_uV, step_uV;
+	struct regulator_config cfg = {};
+	struct device *dev = &i2c->dev;
+	struct regulator_desc *desc;
+	struct regulator_dev *rdev;
+	struct gpio_desc *enable;
+	struct regmap *regmap;
+	bool vsel_high;
+	int ret;
+
+	desc = devm_kzalloc(dev, sizeof(*desc), GFP_KERNEL);
+	if (!desc)
+		return -ENOMEM;
+
+	enable = devm_gpiod_get_optional(dev, "enable", GPIOD_OUT_HIGH);
+	if (IS_ERR(enable))
+		return dev_err_probe(dev, PTR_ERR(enable), "Failed get 'enable' gpio\n");
+
+	regmap = devm_regmap_init_i2c(i2c, &rt8092_regmap_cfg);
+	if (IS_ERR(regmap))
+		return dev_err_probe(dev, PTR_ERR(regmap), "Failed to init regmap\n");
+
+	vsel_high = device_property_read_bool(dev, "richtek,vsel-active-high");
+
+	ret = rt8092_get_vbank_index(regmap, vsel_high, &vbank_idx);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to get VOUT bank index\n");
+
+	/*
+	 * step VOUT = STEP_UV * 2^vbank_idx
+	 * min VOUT  = (BASEUV + STEPUV * VMIN_SEL) * 2^vbank_idx
+	 */
+	step_uV = RT8092_VOUT_STEPUV << vbank_idx;
+	min_uV = (RT8092_VOUT_BASEUV + RT8092_VOUT_STEPUV * RT8092_VOUT_MINSEL) << vbank_idx;
+
+	desc->name = "rt8092";
+	desc->owner = THIS_MODULE;
+	desc->type = REGULATOR_VOLTAGE;
+	desc->ops = &rt8092_regulator_ops;
+	desc->n_voltages = RT8092_NUM_VOLTS;
+	desc->min_uV = min_uV;
+	desc->uV_step = step_uV;
+	desc->linear_min_sel = RT8092_VOUT_MINSEL;
+	desc->enable_reg = desc->vsel_reg = vsel_high ? RT8092_REG_VOUTH : RT8092_REG_VOUTL;
+	desc->vsel_mask = RT8092_VSEL_MASK;
+	desc->enable_mask = RT8092_VOUTEN_MASK;
+	desc->enable_time = RT8092_INITSS_US;
+	desc->of_map_mode = rt8092_of_map_mode;
+
+	cfg.dev = dev;
+	cfg.of_node = dev_of_node(dev);
+	cfg.init_data = of_get_regulator_init_data(dev, dev_of_node(dev), desc);
+
+	rdev = devm_regulator_register(dev, desc, &cfg);
+	if (IS_ERR(rdev))
+		return dev_err_probe(dev, PTR_ERR(rdev), "Failed to register regulator\n");
+
+	return 0;
+}
+
+static const struct of_device_id rt8092_device_tables[] = {
+	{ .compatible = "richtek,rt8092" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, rt8092_device_tables);
+
+static struct i2c_driver rt8092_driver = {
+	.driver = {
+		.name = "rt8092",
+		.of_match_table = rt8092_device_tables,
+	},
+	.probe = rt8092_probe,
+};
+module_i2c_driver(rt8092_driver);
+
+MODULE_AUTHOR("ChiYuan Huang <cy_huang@richtek.com>");
+MODULE_DESCRIPTION("Richtek RT8092 Regulator Driver");
+MODULE_LICENSE("GPL");