1// SPDX-License-Identifier: GPL-2.0+
  2//
  3// sy8106a-regulator.c - Regulator device driver for SY8106A
  4//
  5// Copyright (C) 2016 Ondřej Jirman <megous@megous.com>
  6// Copyright (c) 2017-2018 Icenowy Zheng <icenowy@aosc.io>
  7
  8#include <linux/err.h>
  9#include <linux/i2c.h>
 10#include <linux/module.h>
 11#include <linux/regmap.h>
 12#include <linux/regulator/driver.h>
 13#include <linux/regulator/of_regulator.h>
 14
 15#define SY8106A_REG_VOUT1_SEL		0x01
 16#define SY8106A_REG_VOUT_COM		0x02
 17#define SY8106A_REG_VOUT1_SEL_MASK	0x7f
 18#define SY8106A_DISABLE_REG		BIT(0)
 19/*
 20 * The I2C controlled voltage will only work when this bit is set; otherwise
 21 * it will behave like a fixed regulator.
 22 */
 23#define SY8106A_GO_BIT			BIT(7)
 24
 25static const struct regmap_config sy8106a_regmap_config = {
 26	.reg_bits = 8,
 27	.val_bits = 8,
 28};
 29
 30static const struct regulator_ops sy8106a_ops = {
 31	.set_voltage_sel = regulator_set_voltage_sel_regmap,
 32	.set_voltage_time_sel = regulator_set_voltage_time_sel,
 33	.get_voltage_sel = regulator_get_voltage_sel_regmap,
 34	.list_voltage = regulator_list_voltage_linear,
 35	/* Enabling/disabling the regulator is not yet implemented */
 36};
 37
 38/* Default limits measured in millivolts */
 39#define SY8106A_MIN_MV		680
 40#define SY8106A_MAX_MV		1950
 41#define SY8106A_STEP_MV		10
 42
 43static const struct regulator_desc sy8106a_reg = {
 44	.name = "SY8106A",
 45	.id = 0,
 46	.ops = &sy8106a_ops,
 47	.type = REGULATOR_VOLTAGE,
 48	.n_voltages = ((SY8106A_MAX_MV - SY8106A_MIN_MV) / SY8106A_STEP_MV) + 1,
 49	.min_uV = (SY8106A_MIN_MV * 1000),
 50	.uV_step = (SY8106A_STEP_MV * 1000),
 51	.vsel_reg = SY8106A_REG_VOUT1_SEL,
 52	.vsel_mask = SY8106A_REG_VOUT1_SEL_MASK,
 53	/*
 54	 * This ramp_delay is a conservative default value which works on
 55	 * H3/H5 boards VDD-CPUX situations.
 56	 */
 57	.ramp_delay = 200,
 58	.owner = THIS_MODULE,
 59};
 60
 61/*
 62 * I2C driver interface functions
 63 */
 64static int sy8106a_i2c_probe(struct i2c_client *i2c)
 65{
 66	struct device *dev = &i2c->dev;
 67	struct regulator_dev *rdev;
 68	struct regulator_config config = { };
 69	struct regmap *regmap;
 70	unsigned int reg, vsel;
 71	u32 fixed_voltage;
 72	int error;
 73
 74	error = of_property_read_u32(dev->of_node, "silergy,fixed-microvolt",
 75				     &fixed_voltage);
 76	if (error)
 77		return error;
 78
 79	if (fixed_voltage < SY8106A_MIN_MV * 1000 ||
 80	    fixed_voltage > SY8106A_MAX_MV * 1000)
 81		return -EINVAL;
 82
 83	regmap = devm_regmap_init_i2c(i2c, &sy8106a_regmap_config);
 84	if (IS_ERR(regmap)) {
 85		error = PTR_ERR(regmap);
 86		dev_err(dev, "Failed to allocate register map: %d\n", error);
 87		return error;
 88	}
 89
 90	config.dev = &i2c->dev;
 91	config.regmap = regmap;
 92
 93	config.of_node = dev->of_node;
 94	config.init_data = of_get_regulator_init_data(dev, dev->of_node,
 95						      &sy8106a_reg);
 96
 97	if (!config.init_data)
 98		return -ENOMEM;
 99
100	/* Ensure GO_BIT is enabled when probing */
101	error = regmap_read(regmap, SY8106A_REG_VOUT1_SEL, &reg);
102	if (error)
103		return error;
104
105	if (!(reg & SY8106A_GO_BIT)) {
106		vsel = (fixed_voltage / 1000 - SY8106A_MIN_MV) /
107		       SY8106A_STEP_MV;
108
109		error = regmap_write(regmap, SY8106A_REG_VOUT1_SEL,
110				     vsel | SY8106A_GO_BIT);
111		if (error)
112			return error;
113	}
114
115	/* Probe regulator */
116	rdev = devm_regulator_register(&i2c->dev, &sy8106a_reg, &config);
117	if (IS_ERR(rdev)) {
118		error = PTR_ERR(rdev);
119		dev_err(&i2c->dev, "Failed to register SY8106A regulator: %d\n", error);
120		return error;
121	}
122
123	return 0;
124}
125
126static const struct of_device_id sy8106a_i2c_of_match[] = {
127	{ .compatible = "silergy,sy8106a" },
128	{ },
129};
130MODULE_DEVICE_TABLE(of, sy8106a_i2c_of_match);
131
132static const struct i2c_device_id sy8106a_i2c_id[] = {
133	{ "sy8106a", 0 },
134	{ },
135};
136MODULE_DEVICE_TABLE(i2c, sy8106a_i2c_id);
137
138static struct i2c_driver sy8106a_regulator_driver = {
139	.driver = {
140		.name = "sy8106a",
141		.of_match_table	= of_match_ptr(sy8106a_i2c_of_match),
 
142	},
143	.probe_new = sy8106a_i2c_probe,
144	.id_table = sy8106a_i2c_id,
145};
146
147module_i2c_driver(sy8106a_regulator_driver);
148
149MODULE_AUTHOR("Ondřej Jirman <megous@megous.com>");
150MODULE_AUTHOR("Icenowy Zheng <icenowy@aosc.io>");
151MODULE_DESCRIPTION("Regulator device driver for Silergy SY8106A");
152MODULE_LICENSE("GPL");

  1// SPDX-License-Identifier: GPL-2.0+
  2//
  3// sy8106a-regulator.c - Regulator device driver for SY8106A
  4//
  5// Copyright (C) 2016 Ondřej Jirman <megous@megous.com>
  6// Copyright (c) 2017-2018 Icenowy Zheng <icenowy@aosc.io>
  7
  8#include <linux/err.h>
  9#include <linux/i2c.h>
 10#include <linux/module.h>
 11#include <linux/regmap.h>
 12#include <linux/regulator/driver.h>
 13#include <linux/regulator/of_regulator.h>
 14
 15#define SY8106A_REG_VOUT1_SEL		0x01
 16#define SY8106A_REG_VOUT_COM		0x02
 17#define SY8106A_REG_VOUT1_SEL_MASK	0x7f
 18#define SY8106A_DISABLE_REG		BIT(0)
 19/*
 20 * The I2C controlled voltage will only work when this bit is set; otherwise
 21 * it will behave like a fixed regulator.
 22 */
 23#define SY8106A_GO_BIT			BIT(7)
 24
 25static const struct regmap_config sy8106a_regmap_config = {
 26	.reg_bits = 8,
 27	.val_bits = 8,
 28};
 29
 30static const struct regulator_ops sy8106a_ops = {
 31	.set_voltage_sel = regulator_set_voltage_sel_regmap,
 32	.set_voltage_time_sel = regulator_set_voltage_time_sel,
 33	.get_voltage_sel = regulator_get_voltage_sel_regmap,
 34	.list_voltage = regulator_list_voltage_linear,
 35	/* Enabling/disabling the regulator is not yet implemented */
 36};
 37
 38/* Default limits measured in millivolts */
 39#define SY8106A_MIN_MV		680
 40#define SY8106A_MAX_MV		1950
 41#define SY8106A_STEP_MV		10
 42
 43static const struct regulator_desc sy8106a_reg = {
 44	.name = "SY8106A",
 45	.id = 0,
 46	.ops = &sy8106a_ops,
 47	.type = REGULATOR_VOLTAGE,
 48	.n_voltages = ((SY8106A_MAX_MV - SY8106A_MIN_MV) / SY8106A_STEP_MV) + 1,
 49	.min_uV = (SY8106A_MIN_MV * 1000),
 50	.uV_step = (SY8106A_STEP_MV * 1000),
 51	.vsel_reg = SY8106A_REG_VOUT1_SEL,
 52	.vsel_mask = SY8106A_REG_VOUT1_SEL_MASK,
 53	/*
 54	 * This ramp_delay is a conservative default value which works on
 55	 * H3/H5 boards VDD-CPUX situations.
 56	 */
 57	.ramp_delay = 200,
 58	.owner = THIS_MODULE,
 59};
 60
 61/*
 62 * I2C driver interface functions
 63 */
 64static int sy8106a_i2c_probe(struct i2c_client *i2c)
 65{
 66	struct device *dev = &i2c->dev;
 67	struct regulator_dev *rdev;
 68	struct regulator_config config = { };
 69	struct regmap *regmap;
 70	unsigned int reg, vsel;
 71	u32 fixed_voltage;
 72	int error;
 73
 74	error = of_property_read_u32(dev->of_node, "silergy,fixed-microvolt",
 75				     &fixed_voltage);
 76	if (error)
 77		return error;
 78
 79	if (fixed_voltage < SY8106A_MIN_MV * 1000 ||
 80	    fixed_voltage > SY8106A_MAX_MV * 1000)
 81		return -EINVAL;
 82
 83	regmap = devm_regmap_init_i2c(i2c, &sy8106a_regmap_config);
 84	if (IS_ERR(regmap)) {
 85		error = PTR_ERR(regmap);
 86		dev_err(dev, "Failed to allocate register map: %d\n", error);
 87		return error;
 88	}
 89
 90	config.dev = &i2c->dev;
 91	config.regmap = regmap;
 92
 93	config.of_node = dev->of_node;
 94	config.init_data = of_get_regulator_init_data(dev, dev->of_node,
 95						      &sy8106a_reg);
 96
 97	if (!config.init_data)
 98		return -ENOMEM;
 99
100	/* Ensure GO_BIT is enabled when probing */
101	error = regmap_read(regmap, SY8106A_REG_VOUT1_SEL, &reg);
102	if (error)
103		return error;
104
105	if (!(reg & SY8106A_GO_BIT)) {
106		vsel = (fixed_voltage / 1000 - SY8106A_MIN_MV) /
107		       SY8106A_STEP_MV;
108
109		error = regmap_write(regmap, SY8106A_REG_VOUT1_SEL,
110				     vsel | SY8106A_GO_BIT);
111		if (error)
112			return error;
113	}
114
115	/* Probe regulator */
116	rdev = devm_regulator_register(&i2c->dev, &sy8106a_reg, &config);
117	if (IS_ERR(rdev)) {
118		error = PTR_ERR(rdev);
119		dev_err(&i2c->dev, "Failed to register SY8106A regulator: %d\n", error);
120		return error;
121	}
122
123	return 0;
124}
125
126static const struct of_device_id sy8106a_i2c_of_match[] = {
127	{ .compatible = "silergy,sy8106a" },
128	{ },
129};
130MODULE_DEVICE_TABLE(of, sy8106a_i2c_of_match);
131
132static const struct i2c_device_id sy8106a_i2c_id[] = {
133	{ "sy8106a", 0 },
134	{ },
135};
136MODULE_DEVICE_TABLE(i2c, sy8106a_i2c_id);
137
138static struct i2c_driver sy8106a_regulator_driver = {
139	.driver = {
140		.name = "sy8106a",
141		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
142		.of_match_table	= sy8106a_i2c_of_match,
143	},
144	.probe = sy8106a_i2c_probe,
145	.id_table = sy8106a_i2c_id,
146};
147
148module_i2c_driver(sy8106a_regulator_driver);
149
150MODULE_AUTHOR("Ondřej Jirman <megous@megous.com>");
151MODULE_AUTHOR("Icenowy Zheng <icenowy@aosc.io>");
152MODULE_DESCRIPTION("Regulator device driver for Silergy SY8106A");
153MODULE_LICENSE("GPL");