1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // AWINIC AW37503 Regulator Driver
4 //
5 // Copyright (C) 2023 awinic. All Rights Reserved
6 //
7 // Author: <like@awinic.com>
8 
9 #include <linux/err.h>
10 #include <linux/gpio/consumer.h>
11 #include <linux/i2c.h>
12 #include <linux/module.h>
13 #include <linux/regmap.h>
14 #include <linux/regulator/driver.h>
15 #include <linux/regulator/machine.h>
16 
17 #define AW37503_REG_VPOS		0x00
18 #define AW37503_REG_VNEG		0x01
19 #define AW37503_REG_APPS		0x03
20 #define AW37503_REG_CONTROL		0x04
21 #define AW37503_REG_WPRTEN		0x21
22 
23 #define AW37503_VOUT_MASK		0x1F
24 #define AW37503_VOUT_N_VOLTAGE		0x15
25 #define AW37503_VOUT_VMIN		4000000
26 #define AW37503_VOUT_VMAX		6000000
27 #define AW37503_VOUT_STEP		100000
28 
29 #define AW37503_REG_APPS_DIS_VPOS	BIT(1)
30 #define AW37503_REG_APPS_DIS_VNEG	BIT(0)
31 
32 #define AW37503_REGULATOR_ID_VPOS	0
33 #define AW37503_REGULATOR_ID_VNEG	1
34 #define AW37503_MAX_REGULATORS		2
35 
36 struct aw37503_reg_pdata {
37 	struct gpio_desc *en_gpiod;
38 	int ena_gpio_state;
39 };
40 
41 struct aw37503_regulator {
42 	struct device *dev;
43 	struct aw37503_reg_pdata reg_pdata[AW37503_MAX_REGULATORS];
44 };
45 
aw37503_regulator_enable(struct regulator_dev * rdev)46 static int aw37503_regulator_enable(struct regulator_dev *rdev)
47 {
48 	struct aw37503_regulator *chip = rdev_get_drvdata(rdev);
49 	int id = rdev_get_id(rdev);
50 	struct aw37503_reg_pdata *rpdata = &chip->reg_pdata[id];
51 	int ret;
52 
53 	if (!IS_ERR(rpdata->en_gpiod)) {
54 		gpiod_set_value_cansleep(rpdata->en_gpiod, 1);
55 		rpdata->ena_gpio_state = 1;
56 	}
57 
58 	/* Hardware automatically enable discharge bit in enable */
59 	if (rdev->constraints->active_discharge ==
60 			REGULATOR_ACTIVE_DISCHARGE_DISABLE) {
61 		ret = regulator_set_active_discharge_regmap(rdev, false);
62 		if (ret < 0) {
63 			dev_err(chip->dev, "Failed to disable active discharge: %d\n",
64 				ret);
65 			return ret;
66 		}
67 	}
68 
69 	return 0;
70 }
71 
aw37503_regulator_disable(struct regulator_dev * rdev)72 static int aw37503_regulator_disable(struct regulator_dev *rdev)
73 {
74 	struct aw37503_regulator *chip = rdev_get_drvdata(rdev);
75 	int id = rdev_get_id(rdev);
76 	struct aw37503_reg_pdata *rpdata = &chip->reg_pdata[id];
77 
78 	if (!IS_ERR(rpdata->en_gpiod)) {
79 		gpiod_set_value_cansleep(rpdata->en_gpiod, 0);
80 		rpdata->ena_gpio_state = 0;
81 	}
82 
83 	return 0;
84 }
85 
aw37503_regulator_is_enabled(struct regulator_dev * rdev)86 static int aw37503_regulator_is_enabled(struct regulator_dev *rdev)
87 {
88 	struct aw37503_regulator *chip = rdev_get_drvdata(rdev);
89 	int id = rdev_get_id(rdev);
90 	struct aw37503_reg_pdata *rpdata = &chip->reg_pdata[id];
91 
92 	if (!IS_ERR(rpdata->en_gpiod))
93 		return rpdata->ena_gpio_state;
94 
95 	return 1;
96 }
97 
98 static const struct regulator_ops aw37503_regulator_ops = {
99 	.enable = aw37503_regulator_enable,
100 	.disable = aw37503_regulator_disable,
101 	.is_enabled = aw37503_regulator_is_enabled,
102 	.list_voltage = regulator_list_voltage_linear,
103 	.map_voltage = regulator_map_voltage_linear,
104 	.get_voltage_sel = regulator_get_voltage_sel_regmap,
105 	.set_voltage_sel = regulator_set_voltage_sel_regmap,
106 	.set_active_discharge = regulator_set_active_discharge_regmap,
107 };
108 
aw37503_of_parse_cb(struct device_node * np,const struct regulator_desc * desc,struct regulator_config * config)109 static int aw37503_of_parse_cb(struct device_node *np,
110 				const struct regulator_desc *desc,
111 				struct regulator_config *config)
112 {
113 	struct aw37503_regulator *chip = config->driver_data;
114 	struct aw37503_reg_pdata *rpdata = &chip->reg_pdata[desc->id];
115 	int ret;
116 
117 	rpdata->en_gpiod = devm_fwnode_gpiod_get(chip->dev, of_fwnode_handle(np),
118 						 "enable", GPIOD_OUT_LOW,
119 						 "enable");
120 
121 	if (IS_ERR(rpdata->en_gpiod)) {
122 		ret = PTR_ERR(rpdata->en_gpiod);
123 
124 		/* Ignore the error other than probe defer */
125 		if (ret == -EPROBE_DEFER)
126 			return ret;
127 		return 0;
128 	}
129 
130 	return 0;
131 }
132 
133 #define AW37503_REGULATOR_DESC(_id, _name)		\
134 	[AW37503_REGULATOR_ID_##_id] = {		\
135 		.name = "aw37503-"#_name,		\
136 		.supply_name = "vin",			\
137 		.id = AW37503_REGULATOR_ID_##_id,	\
138 		.of_match = of_match_ptr(#_name),	\
139 		.of_parse_cb = aw37503_of_parse_cb,	\
140 		.ops = &aw37503_regulator_ops,		\
141 		.n_voltages = AW37503_VOUT_N_VOLTAGE,	\
142 		.min_uV = AW37503_VOUT_VMIN,		\
143 		.uV_step = AW37503_VOUT_STEP,		\
144 		.enable_time = 500,			\
145 		.vsel_mask = AW37503_VOUT_MASK,	\
146 		.vsel_reg = AW37503_REG_##_id,		\
147 		.active_discharge_off = 0,			\
148 		.active_discharge_on = AW37503_REG_APPS_DIS_##_id, \
149 		.active_discharge_mask = AW37503_REG_APPS_DIS_##_id, \
150 		.active_discharge_reg = AW37503_REG_APPS, \
151 		.type = REGULATOR_VOLTAGE,		\
152 		.owner = THIS_MODULE,			\
153 	}
154 
155 static const struct regulator_desc aw_regs_desc[AW37503_MAX_REGULATORS] = {
156 	AW37503_REGULATOR_DESC(VPOS, outp),
157 	AW37503_REGULATOR_DESC(VNEG, outn),
158 };
159 
160 static const struct regmap_range aw37503_no_reg_ranges[] = {
161 	regmap_reg_range(AW37503_REG_CONTROL + 1,
162 			 AW37503_REG_WPRTEN - 1),
163 };
164 
165 static const struct regmap_access_table aw37503_no_reg_table = {
166 	.no_ranges = aw37503_no_reg_ranges,
167 	.n_no_ranges = ARRAY_SIZE(aw37503_no_reg_ranges),
168 };
169 
170 static const struct regmap_config aw37503_regmap_config = {
171 	.reg_bits	= 8,
172 	.val_bits	= 8,
173 	.max_register	= AW37503_REG_WPRTEN,
174 	.rd_table	= &aw37503_no_reg_table,
175 	.wr_table	= &aw37503_no_reg_table,
176 };
177 
aw37503_probe(struct i2c_client * client)178 static int aw37503_probe(struct i2c_client *client)
179 {
180 	struct device *dev = &client->dev;
181 	struct aw37503_regulator *chip;
182 	struct regulator_dev *rdev;
183 	struct regmap *regmap;
184 	struct regulator_config config = { };
185 	int id;
186 
187 	chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
188 	if (!chip)
189 		return -ENOMEM;
190 
191 	regmap = devm_regmap_init_i2c(client, &aw37503_regmap_config);
192 	if (IS_ERR(regmap))
193 		return dev_err_probe(dev, PTR_ERR(regmap),
194 				     "Failed to init regmap\n");
195 
196 	i2c_set_clientdata(client, chip);
197 	chip->dev = dev;
198 
199 	config.regmap = regmap;
200 	config.dev = dev;
201 	config.driver_data = chip;
202 
203 	for (id = 0; id < AW37503_MAX_REGULATORS; ++id) {
204 		rdev = devm_regulator_register(dev, &aw_regs_desc[id],
205 					       &config);
206 		if (IS_ERR(rdev))
207 			return dev_err_probe(dev, PTR_ERR(rdev),
208 					     "Failed to register regulator %s\n",
209 					     aw_regs_desc[id].name);
210 	}
211 	return 0;
212 }
213 
214 static const struct i2c_device_id aw37503_id[] = {
215 	{.name = "aw37503",},
216 	{},
217 };
218 MODULE_DEVICE_TABLE(i2c, aw37503_id);
219 
220 static const struct of_device_id aw37503_of_match[] = {
221 	{.compatible = "awinic,aw37503",},
222 	{ /* Sentinel */ },
223 };
224 
225 MODULE_DEVICE_TABLE(of, aw37503_of_match);
226 
227 static struct i2c_driver aw37503_i2c_driver = {
228 	.driver = {
229 		.name = "aw37503",
230 		.of_match_table = aw37503_of_match,
231 	},
232 	.probe = aw37503_probe,
233 	.id_table = aw37503_id,
234 };
235 
236 module_i2c_driver(aw37503_i2c_driver);
237 
238 MODULE_DESCRIPTION("aw37503 regulator driver");
239 MODULE_AUTHOR("Alec Li <like@awinic.com>");
240 MODULE_LICENSE("GPL");
241