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#define SY8827N_ID1		3
 23#define SY8827N_ID2		4
 24#define SY8827N_PGOOD		5
 25#define SY8827N_MAX		(SY8827N_PGOOD + 1)
 26
 27#define SY8827N_NVOLTAGES	64
 28#define SY8827N_VSELMIN		600000
 29#define SY8827N_VSELSTEP	12500
 30
 31struct sy8827n_device_info {
 32	struct device *dev;
 33	struct regulator_desc desc;
 34	struct regulator_init_data *regulator;
 35	struct gpio_desc *en_gpio;
 36	unsigned int vsel_reg;
 37};
 38
 39static int sy8827n_set_mode(struct regulator_dev *rdev, unsigned int mode)
 40{
 41	struct sy8827n_device_info *di = rdev_get_drvdata(rdev);
 42
 43	switch (mode) {
 44	case REGULATOR_MODE_FAST:
 45		regmap_update_bits(rdev->regmap, di->vsel_reg,
 46				   SY8827N_MODE, SY8827N_MODE);
 47		break;
 48	case REGULATOR_MODE_NORMAL:
 49		regmap_update_bits(rdev->regmap, di->vsel_reg,
 50				   SY8827N_MODE, 0);
 51		break;
 52	default:
 53		return -EINVAL;
 54	}
 55	return 0;
 56}
 57
 58static unsigned int sy8827n_get_mode(struct regulator_dev *rdev)
 59{
 60	struct sy8827n_device_info *di = rdev_get_drvdata(rdev);
 61	u32 val;
 62	int ret = 0;
 63
 64	ret = regmap_read(rdev->regmap, di->vsel_reg, &val);
 65	if (ret < 0)
 66		return ret;
 67	if (val & SY8827N_MODE)
 68		return REGULATOR_MODE_FAST;
 69	else
 70		return REGULATOR_MODE_NORMAL;
 71}
 72
 73static const struct regulator_ops sy8827n_regulator_ops = {
 74	.set_voltage_sel = regulator_set_voltage_sel_regmap,
 75	.get_voltage_sel = regulator_get_voltage_sel_regmap,
 76	.set_voltage_time_sel = regulator_set_voltage_time_sel,
 77	.map_voltage = regulator_map_voltage_linear,
 78	.list_voltage = regulator_list_voltage_linear,
 79	.enable = regulator_enable_regmap,
 80	.disable = regulator_disable_regmap,
 81	.is_enabled = regulator_is_enabled_regmap,
 82	.set_mode = sy8827n_set_mode,
 83	.get_mode = sy8827n_get_mode,
 84};
 85
 86static int sy8827n_regulator_register(struct sy8827n_device_info *di,
 87			struct regulator_config *config)
 88{
 89	struct regulator_desc *rdesc = &di->desc;
 90	struct regulator_dev *rdev;
 91
 92	rdesc->name = "sy8827n-reg";
 93	rdesc->supply_name = "vin";
 94	rdesc->ops = &sy8827n_regulator_ops;
 95	rdesc->type = REGULATOR_VOLTAGE;
 96	rdesc->n_voltages = SY8827N_NVOLTAGES;
 97	rdesc->enable_reg = di->vsel_reg;
 98	rdesc->enable_mask = SY8827N_BUCK_EN;
 99	rdesc->min_uV = SY8827N_VSELMIN;
100	rdesc->uV_step = SY8827N_VSELSTEP;
101	rdesc->vsel_reg = di->vsel_reg;
102	rdesc->vsel_mask = rdesc->n_voltages - 1;
103	rdesc->owner = THIS_MODULE;
104
105	rdev = devm_regulator_register(di->dev, &di->desc, config);
106	return PTR_ERR_OR_ZERO(rdev);
107}
108
109static bool sy8827n_volatile_reg(struct device *dev, unsigned int reg)
110{
111	if (reg == SY8827N_PGOOD)
112		return true;
113	return false;
114}
115
116static const struct regmap_config sy8827n_regmap_config = {
117	.reg_bits = 8,
118	.val_bits = 8,
119	.volatile_reg = sy8827n_volatile_reg,
120	.num_reg_defaults_raw = SY8827N_MAX,
121	.cache_type = REGCACHE_FLAT,
122};
123
124static int sy8827n_i2c_probe(struct i2c_client *client)
125{
126	struct device *dev = &client->dev;
127	struct device_node *np = dev->of_node;
128	struct sy8827n_device_info *di;
129	struct regulator_config config = { };
130	struct regmap *regmap;
131	int ret;
132
133	di = devm_kzalloc(dev, sizeof(struct sy8827n_device_info), GFP_KERNEL);
134	if (!di)
135		return -ENOMEM;
136
137	di->regulator = of_get_regulator_init_data(dev, np, &di->desc);
138	if (!di->regulator) {
139		dev_err(dev, "Platform data not found!\n");
140		return -EINVAL;
141	}
142
143	di->en_gpio = devm_gpiod_get_optional(dev, "enable", GPIOD_OUT_HIGH);
144	if (IS_ERR(di->en_gpio))
145		return PTR_ERR(di->en_gpio);
146
147	if (of_property_read_bool(np, "silergy,vsel-state-high"))
148		di->vsel_reg = SY8827N_VSEL1;
149	else
150		di->vsel_reg = SY8827N_VSEL0;
151
152	di->dev = dev;
153
154	regmap = devm_regmap_init_i2c(client, &sy8827n_regmap_config);
155	if (IS_ERR(regmap)) {
156		dev_err(dev, "Failed to allocate regmap!\n");
157		return PTR_ERR(regmap);
158	}
159	i2c_set_clientdata(client, di);
160
161	config.dev = di->dev;
162	config.init_data = di->regulator;
163	config.regmap = regmap;
164	config.driver_data = di;
165	config.of_node = np;
166
167	ret = sy8827n_regulator_register(di, &config);
168	if (ret < 0)
169		dev_err(dev, "Failed to register regulator!\n");
170	return ret;
171}
172
173static const struct of_device_id sy8827n_dt_ids[] = {
174	{
175		.compatible = "silergy,sy8827n",
176	},
177	{ }
178};
179MODULE_DEVICE_TABLE(of, sy8827n_dt_ids);
180
181static const struct i2c_device_id sy8827n_id[] = {
182	{ "sy8827n", },
183	{ },
184};
185MODULE_DEVICE_TABLE(i2c, sy8827n_id);
186
187static struct i2c_driver sy8827n_regulator_driver = {
188	.driver = {
189		.name = "sy8827n-regulator",
190		.of_match_table = sy8827n_dt_ids,
191	},
192	.probe_new = sy8827n_i2c_probe,
193	.id_table = sy8827n_id,
194};
195module_i2c_driver(sy8827n_regulator_driver);
196
197MODULE_AUTHOR("Jisheng Zhang <jszhang@kernel.org>");
198MODULE_DESCRIPTION("SY8827N regulator driver");
199MODULE_LICENSE("GPL v2");