regulator: max77838: add max77838 regulator driver (6a1f303c) · Commits · git / linux-net

MAINTAINERS

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		@@ -15074,6 +15074,7 @@ M: Ivaylo Ivanov <ivo.ivanov.ivanov1@gmail.com>
		L: linux-kernel@vger.kernel.org
		S: Maintained
		F: Documentation/devicetree/bindings/regulator/maxim,max77838.yaml
		F: drivers/regulator/max77838-regulator.c

		MAXIM MAX77976 BATTERY CHARGER
		M: Luca Ceresoli <luca@lucaceresoli.net>

drivers/regulator/Kconfig

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		@@ -777,6 +777,14 @@ config REGULATOR_MAX77826
		It includes support for control of output voltage. This
		regulator is found on the Samsung Galaxy S5 (klte) smartphone.

		config REGULATOR_MAX77838
		tristate "Maxim 77838 regulator"
		depends on REGMAP_I2C
		help
		This driver controls a Maxim 77838 regulator via I2C bus.
		The regulator include 4 LDOs and a BUCK regulator. It's
		present on the Samsung Galaxy S7 lineup of smartphones.

		config REGULATOR_MC13XXX_CORE
		tristate

drivers/regulator/Makefile

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		@@ -92,6 +92,7 @@ obj-$(CONFIG_REGULATOR_MAX77686) += max77686-regulator.o
		obj-$(CONFIG_REGULATOR_MAX77693) += max77693-regulator.o
		obj-$(CONFIG_REGULATOR_MAX77802) += max77802-regulator.o
		obj-$(CONFIG_REGULATOR_MAX77826) += max77826-regulator.o
		obj-$(CONFIG_REGULATOR_MAX77838) += max77838-regulator.o
		obj-$(CONFIG_REGULATOR_MAX77857) += max77857-regulator.o
		obj-$(CONFIG_REGULATOR_MC13783) += mc13783-regulator.o
		obj-$(CONFIG_REGULATOR_MC13892) += mc13892-regulator.o

drivers/regulator/max77838-regulator.c

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		// SPDX-License-Identifier: GPL-2.0-or-later
		//
		// regulator driver for Maxim MAX77838
		//
		// based on max77826-regulator.c
		//
		// Copyright (c) 2025, Ivaylo Ivanov <ivo.ivanov.ivanov1@gmail.com>

		#include <linux/kernel.h>
		#include <linux/module.h>
		#include <linux/init.h>
		#include <linux/err.h>
		#include <linux/of.h>
		#include <linux/platform_device.h>
		#include <linux/regulator/driver.h>
		#include <linux/regulator/of_regulator.h>
		#include <linux/i2c.h>
		#include <linux/regmap.h>

		enum max77838_registers {
		MAX77838_REG_DEVICE_ID = 0x00,
		MAX77838_REG_TOPSYS_STAT,
		MAX77838_REG_STAT,
		MAX77838_REG_EN,
		MAX77838_REG_GPIO_PD_CTRL,
		MAX77838_REG_UVLO_CFG1,
		/* 0x06 - 0x0B: reserved */
		MAX77838_REG_I2C_CFG = 0x0C,
		/* 0x0D - 0x0F: reserved */
		MAX77838_REG_LDO1_CFG = 0x10,
		MAX77838_REG_LDO2_CFG,
		MAX77838_REG_LDO3_CFG,
		MAX77838_REG_LDO4_CFG,
		/* 0x14 - 0x1F: reserved */
		MAX77838_REG_BUCK_CFG1 = 0x20,
		MAX77838_REG_BUCK_VOUT,
		};

		enum max77838_regulators {
		MAX77838_LDO1 = 0,
		MAX77838_LDO2,
		MAX77838_LDO3,
		MAX77838_LDO4,
		MAX77838_BUCK,
		MAX77838_MAX_REGULATORS,
		};

		#define MAX77838_MASK_LDO 0x7f
		#define MAX77838_MASK_BUCK 0xff

		#define MAX77838_LDO1_EN BIT(0)
		#define MAX77838_LDO2_EN BIT(1)
		#define MAX77838_LDO3_EN BIT(2)
		#define MAX77838_LDO4_EN BIT(3)
		#define MAX77838_BUCK_EN BIT(4)

		#define MAX77838_BUCK_AD BIT(3)
		#define MAX77838_LDO_AD BIT(7)

		#define MAX77838_LDO_VOLT_MIN 600000
		#define MAX77838_LDO_VOLT_MAX 3775000
		#define MAX77838_LDO_VOLT_STEP 25000

		#define MAX77838_BUCK_VOLT_MIN 500000
		#define MAX77838_BUCK_VOLT_MAX 2093750
		#define MAX77838_BUCK_VOLT_STEP 6250

		#define MAX77838_VOLT_RANGE(_type) \
		((MAX77838_ ## _type ## _VOLT_MAX - \
		MAX77838_ ## _type ## _VOLT_MIN) / \
		MAX77838_ ## _type ## _VOLT_STEP + 1)

		#define MAX77838_LDO(_id) \
		[MAX77838_LDO ## _id] = { \
		.id = MAX77838_LDO ## _id, \
		.name = "ldo"#_id, \
		.of_match = of_match_ptr("ldo"#_id), \
		.regulators_node = "regulators", \
		.ops = &max77838_regulator_ops, \
		.min_uV = MAX77838_LDO_VOLT_MIN, \
		.uV_step = MAX77838_LDO_VOLT_STEP, \
		.n_voltages = MAX77838_VOLT_RANGE(LDO), \
		.enable_reg = MAX77838_REG_EN, \
		.enable_mask = MAX77838_LDO ## _id ## _EN, \
		.vsel_reg = MAX77838_REG_LDO ## _id ## _CFG, \
		.vsel_mask = MAX77838_MASK_LDO, \
		.active_discharge_off = 0, \
		.active_discharge_on = MAX77838_LDO_AD, \
		.active_discharge_mask = MAX77838_LDO_AD, \
		.active_discharge_reg = MAX77838_REG_LDO ## _id ## _CFG, \
		.owner = THIS_MODULE, \
		}

		#define MAX77838_BUCK_DESC \
		[MAX77838_BUCK] = { \
		.id = MAX77838_BUCK, \
		.name = "buck", \
		.of_match = of_match_ptr("buck"), \
		.regulators_node = "regulators", \
		.ops = &max77838_regulator_ops, \
		.min_uV = MAX77838_BUCK_VOLT_MIN, \
		.uV_step = MAX77838_BUCK_VOLT_STEP, \
		.n_voltages = MAX77838_VOLT_RANGE(BUCK), \
		.enable_reg = MAX77838_REG_EN, \
		.enable_mask = MAX77838_BUCK_EN, \
		.vsel_reg = MAX77838_REG_BUCK_VOUT, \
		.vsel_mask = MAX77838_MASK_BUCK, \
		.active_discharge_off = 0, \
		.active_discharge_on = MAX77838_BUCK_AD, \
		.active_discharge_mask = MAX77838_BUCK_AD, \
		.active_discharge_reg = MAX77838_REG_BUCK_CFG1, \
		.owner = THIS_MODULE, \
		}

		struct max77838_regulator_info {
		struct regmap *regmap;
		};

		static const struct regmap_config max77838_regmap_config = {
		.reg_bits = 8,
		.val_bits = 8,
		.max_register = MAX77838_REG_BUCK_VOUT,
		};

		static const struct regulator_ops max77838_regulator_ops = {
		.enable = regulator_enable_regmap,
		.disable = regulator_disable_regmap,
		.is_enabled = regulator_is_enabled_regmap,
		.list_voltage = regulator_list_voltage_linear,
		.map_voltage = regulator_map_voltage_linear,
		.get_voltage_sel = regulator_get_voltage_sel_regmap,
		.set_voltage_sel = regulator_set_voltage_sel_regmap,
		.set_active_discharge = regulator_set_active_discharge_regmap,
		};

		static const struct regulator_desc max77838_regulators_desc[] = {
		MAX77838_LDO(1),
		MAX77838_LDO(2),
		MAX77838_LDO(3),
		MAX77838_LDO(4),
		MAX77838_BUCK_DESC,
		};

		static int max77838_read_device_id(struct regmap regmap, struct device dev)
		{
		unsigned int device_id;
		int ret;

		ret = regmap_read(regmap, MAX77838_REG_DEVICE_ID, &device_id);
		if (!ret)
		dev_dbg(dev, "DEVICE_ID: 0x%x\n", device_id);

		return ret;
		}

		static int max77838_i2c_probe(struct i2c_client *client)
		{
		struct device *dev = &client->dev;
		struct max77838_regulator_info *info;
		struct regulator_config config = {};
		struct regulator_dev *rdev;
		struct regmap *regmap;
		int i;

		info = devm_kzalloc(dev, sizeof(struct max77838_regulator_info),
		GFP_KERNEL);
		if (!info)
		return -ENOMEM;

		regmap = devm_regmap_init_i2c(client, &max77838_regmap_config);
		if (IS_ERR(regmap)) {
		dev_err(dev, "Failed to allocate regmap!\n");
		return PTR_ERR(regmap);
		}

		info->regmap = regmap;
		i2c_set_clientdata(client, info);

		config.dev = dev;
		config.regmap = regmap;
		config.driver_data = info;

		for (i = 0; i < MAX77838_MAX_REGULATORS; i++) {
		rdev = devm_regulator_register(dev,
		&max77838_regulators_desc[i],
		&config);
		if (IS_ERR(rdev)) {
		dev_err(dev, "Failed to register regulator!\n");
		return PTR_ERR(rdev);
		}
		}

		return max77838_read_device_id(regmap, dev);
		}

		static const struct of_device_id __maybe_unused max77838_of_match[] = {
		{ .compatible = "maxim,max77838" },
		{ /* sentinel */ }
		};
		MODULE_DEVICE_TABLE(of, max77838_of_match);

		static const struct i2c_device_id max77838_id[] = {
		{ "max77838-regulator" },
		{ /* sentinel */ }
		};
		MODULE_DEVICE_TABLE(i2c, max77838_id);

		static struct i2c_driver max77838_regulator_driver = {
		.driver = {
		.name = "max77838",
		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
		.of_match_table = of_match_ptr(max77838_of_match),
		},
		.probe = max77838_i2c_probe,
		.id_table = max77838_id,
		};
		module_i2c_driver(max77838_regulator_driver);

		MODULE_AUTHOR("Ivaylo Ivanov <ivo.ivanov.ivanov1@gmail.com>");
		MODULE_DESCRIPTION("MAX77838 PMIC regulator driver");
		MODULE_LICENSE("GPL");