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.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
31 struct 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
sy8827n_set_mode(struct regulator_dev * rdev,unsigned int mode)39 static 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
sy8827n_get_mode(struct regulator_dev * rdev)58 static 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
73 static 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
sy8827n_regulator_register(struct sy8827n_device_info * di,struct regulator_config * config)86 static 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
sy8827n_volatile_reg(struct device * dev,unsigned int reg)109 static bool sy8827n_volatile_reg(struct device *dev, unsigned int reg)
110 {
111 if (reg == SY8827N_PGOOD)
112 return true;
113 return false;
114 }
115
116 static 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
sy8827n_i2c_probe(struct i2c_client * client)124 static 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
173 static const struct of_device_id sy8827n_dt_ids[] = {
174 {
175 .compatible = "silergy,sy8827n",
176 },
177 { }
178 };
179 MODULE_DEVICE_TABLE(of, sy8827n_dt_ids);
180
181 static const struct i2c_device_id sy8827n_id[] = {
182 { "sy8827n", },
183 { },
184 };
185 MODULE_DEVICE_TABLE(i2c, sy8827n_id);
186
187 static struct i2c_driver sy8827n_regulator_driver = {
188 .driver = {
189 .name = "sy8827n-regulator",
190 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
191 .of_match_table = sy8827n_dt_ids,
192 },
193 .probe = sy8827n_i2c_probe,
194 .id_table = sy8827n_id,
195 };
196 module_i2c_driver(sy8827n_regulator_driver);
197
198 MODULE_AUTHOR("Jisheng Zhang <jszhang@kernel.org>");
199 MODULE_DESCRIPTION("SY8827N regulator driver");
200 MODULE_LICENSE("GPL v2");
201