1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * isl6271a-regulator.c
4  *
5  * Support for Intersil ISL6271A voltage regulator
6  *
7  * Copyright (C) 2010 Marek Vasut <marek.vasut@gmail.com>
8  */
9 
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/err.h>
14 #include <linux/platform_device.h>
15 #include <linux/regulator/driver.h>
16 #include <linux/i2c.h>
17 #include <linux/slab.h>
18 
19 #define	ISL6271A_VOLTAGE_MIN	850000
20 #define	ISL6271A_VOLTAGE_MAX	1600000
21 #define	ISL6271A_VOLTAGE_STEP	50000
22 
23 /* PMIC details */
24 struct isl_pmic {
25 	struct i2c_client	*client;
26 	struct mutex		mtx;
27 };
28 
29 static int isl6271a_get_voltage_sel(struct regulator_dev *dev)
30 {
31 	struct isl_pmic *pmic = rdev_get_drvdata(dev);
32 	int idx;
33 
34 	mutex_lock(&pmic->mtx);
35 
36 	idx = i2c_smbus_read_byte(pmic->client);
37 	if (idx < 0)
38 		dev_err(&pmic->client->dev, "Error getting voltage\n");
39 
40 	mutex_unlock(&pmic->mtx);
41 	return idx;
42 }
43 
44 static int isl6271a_set_voltage_sel(struct regulator_dev *dev,
45 				    unsigned selector)
46 {
47 	struct isl_pmic *pmic = rdev_get_drvdata(dev);
48 	int err;
49 
50 	mutex_lock(&pmic->mtx);
51 
52 	err = i2c_smbus_write_byte(pmic->client, selector);
53 	if (err < 0)
54 		dev_err(&pmic->client->dev, "Error setting voltage\n");
55 
56 	mutex_unlock(&pmic->mtx);
57 	return err;
58 }
59 
60 static const struct regulator_ops isl_core_ops = {
61 	.get_voltage_sel = isl6271a_get_voltage_sel,
62 	.set_voltage_sel = isl6271a_set_voltage_sel,
63 	.list_voltage	= regulator_list_voltage_linear,
64 	.map_voltage	= regulator_map_voltage_linear,
65 };
66 
67 static const struct regulator_ops isl_fixed_ops = {
68 	.list_voltage	= regulator_list_voltage_linear,
69 };
70 
71 static const struct regulator_desc isl_rd[] = {
72 	{
73 		.name		= "Core Buck",
74 		.id		= 0,
75 		.n_voltages	= 16,
76 		.ops		= &isl_core_ops,
77 		.type		= REGULATOR_VOLTAGE,
78 		.owner		= THIS_MODULE,
79 		.min_uV		= ISL6271A_VOLTAGE_MIN,
80 		.uV_step	= ISL6271A_VOLTAGE_STEP,
81 	}, {
82 		.name		= "LDO1",
83 		.id		= 1,
84 		.n_voltages	= 1,
85 		.ops		= &isl_fixed_ops,
86 		.type		= REGULATOR_VOLTAGE,
87 		.owner		= THIS_MODULE,
88 		.min_uV		= 1100000,
89 	}, {
90 		.name		= "LDO2",
91 		.id		= 2,
92 		.n_voltages	= 1,
93 		.ops		= &isl_fixed_ops,
94 		.type		= REGULATOR_VOLTAGE,
95 		.owner		= THIS_MODULE,
96 		.min_uV		= 1300000,
97 	},
98 };
99 
100 static int isl6271a_probe(struct i2c_client *i2c)
101 {
102 	const struct i2c_device_id *id = i2c_client_get_device_id(i2c);
103 	struct regulator_dev *rdev;
104 	struct regulator_config config = { };
105 	struct regulator_init_data *init_data	= dev_get_platdata(&i2c->dev);
106 	struct isl_pmic *pmic;
107 	int i;
108 
109 	if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
110 		return -EIO;
111 
112 	pmic = devm_kzalloc(&i2c->dev, sizeof(struct isl_pmic), GFP_KERNEL);
113 	if (!pmic)
114 		return -ENOMEM;
115 
116 	pmic->client = i2c;
117 
118 	mutex_init(&pmic->mtx);
119 
120 	for (i = 0; i < 3; i++) {
121 		config.dev = &i2c->dev;
122 		if (i == 0)
123 			config.init_data = init_data;
124 		else
125 			config.init_data = NULL;
126 		config.driver_data = pmic;
127 
128 		rdev = devm_regulator_register(&i2c->dev, &isl_rd[i], &config);
129 		if (IS_ERR(rdev)) {
130 			dev_err(&i2c->dev, "failed to register %s\n", id->name);
131 			return PTR_ERR(rdev);
132 		}
133 	}
134 
135 	i2c_set_clientdata(i2c, pmic);
136 
137 	return 0;
138 }
139 
140 static const struct i2c_device_id isl6271a_id[] = {
141 	{.name = "isl6271a", 0 },
142 	{ },
143 };
144 
145 MODULE_DEVICE_TABLE(i2c, isl6271a_id);
146 
147 static struct i2c_driver isl6271a_i2c_driver = {
148 	.driver = {
149 		.name = "isl6271a",
150 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
151 	},
152 	.probe = isl6271a_probe,
153 	.id_table = isl6271a_id,
154 };
155 
156 static int __init isl6271a_init(void)
157 {
158 	return i2c_add_driver(&isl6271a_i2c_driver);
159 }
160 
161 static void __exit isl6271a_cleanup(void)
162 {
163 	i2c_del_driver(&isl6271a_i2c_driver);
164 }
165 
166 subsys_initcall(isl6271a_init);
167 module_exit(isl6271a_cleanup);
168 
169 MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
170 MODULE_DESCRIPTION("Intersil ISL6271A voltage regulator driver");
171 MODULE_LICENSE("GPL v2");
172