1// SPDX-License-Identifier: GPL-2.0
  2//
  3// SY8827N regulator driver
  4//
  5// Copyright (C) 2020 Synaptics Incorporated
  6//
  7// Author: Jisheng Zhang <jszhang@kernel.org>
  8
  9#include <linux/gpio/consumer.h>
 10#include <linux/module.h>
 11#include <linux/i2c.h>
 12#include <linux/of_device.h>
 13#include <linux/regmap.h>
 14#include <linux/regulator/driver.h>
 15#include <linux/regulator/of_regulator.h>
 16
 17#define SY8827N_VSEL0		0
 18#define   SY8827N_BUCK_EN	(1 << 7)
 19#define   SY8827N_MODE		(1 << 6)
 20#define SY8827N_VSEL1		1
 21#define SY8827N_CTRL		2
 22
 23#define SY8827N_NVOLTAGES	64
 24#define SY8827N_VSELMIN		600000
 25#define SY8827N_VSELSTEP	12500
 26
 27struct sy8827n_device_info {
 28	struct device *dev;
 29	struct regulator_desc desc;
 30	struct regulator_init_data *regulator;
 31	struct gpio_desc *en_gpio;
 32	unsigned int vsel_reg;
 33};
 34
 35static int sy8827n_set_mode(struct regulator_dev *rdev, unsigned int mode)
 36{
 37	struct sy8827n_device_info *di = rdev_get_drvdata(rdev);
 38
 39	switch (mode) {
 40	case REGULATOR_MODE_FAST:
 41		regmap_update_bits(rdev->regmap, di->vsel_reg,
 42				   SY8827N_MODE, SY8827N_MODE);
 43		break;
 44	case REGULATOR_MODE_NORMAL:
 45		regmap_update_bits(rdev->regmap, di->vsel_reg,
 46				   SY8827N_MODE, 0);
 47		break;
 48	default:
 49		return -EINVAL;
 50	}
 51	return 0;
 52}
 53
 54static unsigned int sy8827n_get_mode(struct regulator_dev *rdev)
 55{
 56	struct sy8827n_device_info *di = rdev_get_drvdata(rdev);
 57	u32 val;
 58	int ret = 0;
 59
 60	ret = regmap_read(rdev->regmap, di->vsel_reg, &val);
 61	if (ret < 0)
 62		return ret;
 63	if (val & SY8827N_MODE)
 64		return REGULATOR_MODE_FAST;
 65	else
 66		return REGULATOR_MODE_NORMAL;
 67}
 68
 69static const struct regulator_ops sy8827n_regulator_ops = {
 70	.set_voltage_sel = regulator_set_voltage_sel_regmap,
 71	.get_voltage_sel = regulator_get_voltage_sel_regmap,
 72	.set_voltage_time_sel = regulator_set_voltage_time_sel,
 73	.map_voltage = regulator_map_voltage_linear,
 74	.list_voltage = regulator_list_voltage_linear,
 75	.enable = regulator_enable_regmap,
 76	.disable = regulator_disable_regmap,
 77	.is_enabled = regulator_is_enabled_regmap,
 78	.set_mode = sy8827n_set_mode,
 79	.get_mode = sy8827n_get_mode,
 80};
 81
 82static int sy8827n_regulator_register(struct sy8827n_device_info *di,
 83			struct regulator_config *config)
 84{
 85	struct regulator_desc *rdesc = &di->desc;
 86	struct regulator_dev *rdev;
 87
 88	rdesc->name = "sy8827n-reg";
 89	rdesc->supply_name = "vin";
 90	rdesc->ops = &sy8827n_regulator_ops;
 91	rdesc->type = REGULATOR_VOLTAGE;
 92	rdesc->n_voltages = SY8827N_NVOLTAGES;
 93	rdesc->enable_reg = di->vsel_reg;
 94	rdesc->enable_mask = SY8827N_BUCK_EN;
 95	rdesc->min_uV = SY8827N_VSELMIN;
 96	rdesc->uV_step = SY8827N_VSELSTEP;
 97	rdesc->vsel_reg = di->vsel_reg;
 98	rdesc->vsel_mask = rdesc->n_voltages - 1;
 99	rdesc->owner = THIS_MODULE;
100
101	rdev = devm_regulator_register(di->dev, &di->desc, config);
102	return PTR_ERR_OR_ZERO(rdev);
103}
104
105static const struct regmap_config sy8827n_regmap_config = {
106	.reg_bits = 8,
107	.val_bits = 8,
108};
109
110static int sy8827n_i2c_probe(struct i2c_client *client)
111{
112	struct device *dev = &client->dev;
113	struct device_node *np = dev->of_node;
114	struct sy8827n_device_info *di;
115	struct regulator_config config = { };
116	struct regmap *regmap;
117	int ret;
118
119	di = devm_kzalloc(dev, sizeof(struct sy8827n_device_info), GFP_KERNEL);
120	if (!di)
121		return -ENOMEM;
122
123	di->regulator = of_get_regulator_init_data(dev, np, &di->desc);
124	if (!di->regulator) {
125		dev_err(dev, "Platform data not found!\n");
126		return -EINVAL;
127	}
128
129	di->en_gpio = devm_gpiod_get_optional(dev, "enable", GPIOD_OUT_HIGH);
130	if (IS_ERR(di->en_gpio))
131		return PTR_ERR(di->en_gpio);
132
133	if (of_property_read_bool(np, "silergy,vsel-state-high"))
134		di->vsel_reg = SY8827N_VSEL1;
135	else
136		di->vsel_reg = SY8827N_VSEL0;
137
138	di->dev = dev;
139
140	regmap = devm_regmap_init_i2c(client, &sy8827n_regmap_config);
141	if (IS_ERR(regmap)) {
142		dev_err(dev, "Failed to allocate regmap!\n");
143		return PTR_ERR(regmap);
144	}
145	i2c_set_clientdata(client, di);
146
147	config.dev = di->dev;
148	config.init_data = di->regulator;
149	config.regmap = regmap;
150	config.driver_data = di;
151	config.of_node = np;
152
153	ret = sy8827n_regulator_register(di, &config);
154	if (ret < 0)
155		dev_err(dev, "Failed to register regulator!\n");
156	return ret;
157}
158
159static const struct of_device_id sy8827n_dt_ids[] = {
160	{
161		.compatible = "silergy,sy8827n",
162	},
163	{ }
164};
165MODULE_DEVICE_TABLE(of, sy8827n_dt_ids);
166
167static const struct i2c_device_id sy8827n_id[] = {
168	{ "sy8827n", },
169	{ },
170};
171MODULE_DEVICE_TABLE(i2c, sy8827n_id);
172
173static struct i2c_driver sy8827n_regulator_driver = {
174	.driver = {
175		.name = "sy8827n-regulator",
176		.of_match_table = of_match_ptr(sy8827n_dt_ids),
177	},
178	.probe_new = sy8827n_i2c_probe,
179	.id_table = sy8827n_id,
180};
181module_i2c_driver(sy8827n_regulator_driver);
182
183MODULE_AUTHOR("Jisheng Zhang <jszhang@kernel.org>");
184MODULE_DESCRIPTION("SY8827N regulator driver");
185MODULE_LICENSE("GPL v2");