max77838-regulator.c

  1// SPDX-License-Identifier: GPL-2.0-or-later
  2//
  3// regulator driver for Maxim MAX77838
  4//
  5// based on max77826-regulator.c
  6//
  7// Copyright (c) 2025, Ivaylo Ivanov <ivo.ivanov.ivanov1@gmail.com>
  8
  9#include <linux/kernel.h>
 10#include <linux/module.h>
 11#include <linux/init.h>
 12#include <linux/err.h>
 13#include <linux/of.h>
 14#include <linux/platform_device.h>
 15#include <linux/regulator/driver.h>
 16#include <linux/regulator/of_regulator.h>
 17#include <linux/i2c.h>
 18#include <linux/regmap.h>
 19
 20enum max77838_registers {
 21	MAX77838_REG_DEVICE_ID = 0x00,
 22	MAX77838_REG_TOPSYS_STAT,
 23	MAX77838_REG_STAT,
 24	MAX77838_REG_EN,
 25	MAX77838_REG_GPIO_PD_CTRL,
 26	MAX77838_REG_UVLO_CFG1,
 27	/* 0x06 - 0x0B: reserved */
 28	MAX77838_REG_I2C_CFG = 0x0C,
 29	/* 0x0D - 0x0F: reserved */
 30	MAX77838_REG_LDO1_CFG = 0x10,
 31	MAX77838_REG_LDO2_CFG,
 32	MAX77838_REG_LDO3_CFG,
 33	MAX77838_REG_LDO4_CFG,
 34	/* 0x14 - 0x1F: reserved */
 35	MAX77838_REG_BUCK_CFG1 = 0x20,
 36	MAX77838_REG_BUCK_VOUT,
 37};
 38
 39enum max77838_regulators {
 40	MAX77838_LDO1 = 0,
 41	MAX77838_LDO2,
 42	MAX77838_LDO3,
 43	MAX77838_LDO4,
 44	MAX77838_BUCK,
 45	MAX77838_MAX_REGULATORS,
 46};
 47
 48#define MAX77838_MASK_LDO		0x7f
 49#define MAX77838_MASK_BUCK		0xff
 50
 51#define MAX77838_LDO1_EN		BIT(0)
 52#define MAX77838_LDO2_EN		BIT(1)
 53#define MAX77838_LDO3_EN		BIT(2)
 54#define MAX77838_LDO4_EN		BIT(3)
 55#define MAX77838_BUCK_EN		BIT(4)
 56
 57#define MAX77838_BUCK_AD		BIT(3)
 58#define MAX77838_LDO_AD			BIT(7)
 59
 60#define MAX77838_LDO_VOLT_MIN		600000
 61#define MAX77838_LDO_VOLT_MAX		3775000
 62#define MAX77838_LDO_VOLT_STEP		25000
 63
 64#define MAX77838_BUCK_VOLT_MIN		500000
 65#define MAX77838_BUCK_VOLT_MAX		2093750
 66#define MAX77838_BUCK_VOLT_STEP		6250
 67
 68#define MAX77838_VOLT_RANGE(_type)				\
 69	((MAX77838_ ## _type ## _VOLT_MAX -			\
 70	  MAX77838_ ## _type ## _VOLT_MIN) /			\
 71	  MAX77838_ ## _type ## _VOLT_STEP + 1)
 72
 73#define MAX77838_LDO(_id)							\
 74	[MAX77838_LDO ## _id] = {						\
 75		.id = MAX77838_LDO ## _id,					\
 76		.name = "ldo"#_id,						\
 77		.of_match = of_match_ptr("ldo"#_id),				\
 78		.regulators_node = "regulators",				\
 79		.ops = &max77838_regulator_ops,					\
 80		.min_uV = MAX77838_LDO_VOLT_MIN,				\
 81		.uV_step = MAX77838_LDO_VOLT_STEP,				\
 82		.n_voltages = MAX77838_VOLT_RANGE(LDO),				\
 83		.enable_reg = MAX77838_REG_EN,					\
 84		.enable_mask = MAX77838_LDO ## _id ## _EN,			\
 85		.vsel_reg = MAX77838_REG_LDO ## _id ## _CFG,			\
 86		.vsel_mask = MAX77838_MASK_LDO,					\
 87		.active_discharge_off = 0,					\
 88		.active_discharge_on = MAX77838_LDO_AD,				\
 89		.active_discharge_mask = MAX77838_LDO_AD,			\
 90		.active_discharge_reg = MAX77838_REG_LDO ## _id ## _CFG,	\
 91		.owner = THIS_MODULE,						\
 92	}
 93
 94#define MAX77838_BUCK_DESC					\
 95	[MAX77838_BUCK] = {					\
 96		.id = MAX77838_BUCK,				\
 97		.name = "buck",					\
 98		.of_match = of_match_ptr("buck"),		\
 99		.regulators_node = "regulators",		\
100		.ops = &max77838_regulator_ops,			\
101		.min_uV = MAX77838_BUCK_VOLT_MIN,		\
102		.uV_step = MAX77838_BUCK_VOLT_STEP,		\
103		.n_voltages = MAX77838_VOLT_RANGE(BUCK),	\
104		.enable_reg = MAX77838_REG_EN,			\
105		.enable_mask = MAX77838_BUCK_EN,		\
106		.vsel_reg = MAX77838_REG_BUCK_VOUT,		\
107		.vsel_mask = MAX77838_MASK_BUCK,		\
108		.active_discharge_off = 0,			\
109		.active_discharge_on = MAX77838_BUCK_AD,	\
110		.active_discharge_mask = MAX77838_BUCK_AD,	\
111		.active_discharge_reg = MAX77838_REG_BUCK_CFG1,	\
112		.owner = THIS_MODULE,				\
113	}
114
115struct max77838_regulator_info {
116	struct regmap *regmap;
117};
118
119static const struct regmap_config max77838_regmap_config = {
120	.reg_bits = 8,
121	.val_bits = 8,
122	.max_register = MAX77838_REG_BUCK_VOUT,
123};
124
125static const struct regulator_ops max77838_regulator_ops = {
126	.enable			= regulator_enable_regmap,
127	.disable		= regulator_disable_regmap,
128	.is_enabled		= regulator_is_enabled_regmap,
129	.list_voltage		= regulator_list_voltage_linear,
130	.map_voltage		= regulator_map_voltage_linear,
131	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
132	.set_voltage_sel	= regulator_set_voltage_sel_regmap,
133	.set_active_discharge	= regulator_set_active_discharge_regmap,
134};
135
136static const struct regulator_desc max77838_regulators_desc[] = {
137	MAX77838_LDO(1),
138	MAX77838_LDO(2),
139	MAX77838_LDO(3),
140	MAX77838_LDO(4),
141	MAX77838_BUCK_DESC,
142};
143
144static int max77838_read_device_id(struct regmap *regmap, struct device *dev)
145{
146	unsigned int device_id;
147	int ret;
148
149	ret = regmap_read(regmap, MAX77838_REG_DEVICE_ID, &device_id);
150	if (!ret)
151		dev_dbg(dev, "DEVICE_ID: 0x%x\n", device_id);
152
153	return ret;
154}
155
156static int max77838_i2c_probe(struct i2c_client *client)
157{
158	struct device *dev = &client->dev;
159	struct max77838_regulator_info *info;
160	struct regulator_config config = {};
161	struct regulator_dev *rdev;
162	struct regmap *regmap;
163	int i;
164
165	info = devm_kzalloc(dev, sizeof(struct max77838_regulator_info),
166			    GFP_KERNEL);
167	if (!info)
168		return -ENOMEM;
169
170	regmap = devm_regmap_init_i2c(client, &max77838_regmap_config);
171	if (IS_ERR(regmap)) {
172		dev_err(dev, "Failed to allocate regmap!\n");
173		return PTR_ERR(regmap);
174	}
175
176	info->regmap = regmap;
177	i2c_set_clientdata(client, info);
178
179	config.dev = dev;
180	config.regmap = regmap;
181	config.driver_data = info;
182
183	for (i = 0; i < MAX77838_MAX_REGULATORS; i++) {
184		rdev = devm_regulator_register(dev,
185					       &max77838_regulators_desc[i],
186					       &config);
187		if (IS_ERR(rdev)) {
188			dev_err(dev, "Failed to register regulator!\n");
189			return PTR_ERR(rdev);
190		}
191	}
192
193	return max77838_read_device_id(regmap, dev);
194}
195
196static const struct of_device_id __maybe_unused max77838_of_match[] = {
197	{ .compatible = "maxim,max77838" },
198	{ /* sentinel */ }
199};
200MODULE_DEVICE_TABLE(of, max77838_of_match);
201
202static const struct i2c_device_id max77838_id[] = {
203	{ "max77838-regulator" },
204	{ /* sentinel */ }
205};
206MODULE_DEVICE_TABLE(i2c, max77838_id);
207
208static struct i2c_driver max77838_regulator_driver = {
209	.driver = {
210		.name = "max77838",
211		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
212		.of_match_table = of_match_ptr(max77838_of_match),
213	},
214	.probe = max77838_i2c_probe,
215	.id_table = max77838_id,
216};
217module_i2c_driver(max77838_regulator_driver);
218
219MODULE_AUTHOR("Ivaylo Ivanov <ivo.ivanov.ivanov1@gmail.com>");
220MODULE_DESCRIPTION("MAX77838 PMIC regulator driver");
221MODULE_LICENSE("GPL");