summaryrefslogtreecommitdiffstats
path: root/drivers/regulator/isl6271a-regulator.c
blob: e4b3592e81767856cdadd4543a6e25bb001d695d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
/*
 * isl6271a-regulator.c
 *
 * Support for Intersil ISL6271A voltage regulator
 *
 * Copyright (C) 2010 Marek Vasut <marek.vasut@gmail.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation version 2.
 *
 * This program is distributed "as is" WITHOUT ANY WARRANTY of any kind,
 * whether express or implied; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/i2c.h>
#include <linux/delay.h>
#include <linux/slab.h>

#define	ISL6271A_VOLTAGE_MIN	850000
#define	ISL6271A_VOLTAGE_MAX	1600000
#define	ISL6271A_VOLTAGE_STEP	50000

/* PMIC details */
struct isl_pmic {
	struct i2c_client	*client;
	struct regulator_dev	*rdev[3];
	struct mutex		mtx;
};

static int isl6271a_get_voltage(struct regulator_dev *dev)
{
	struct isl_pmic *pmic = rdev_get_drvdata(dev);
	int idx, data;

	mutex_lock(&pmic->mtx);

	idx = i2c_smbus_read_byte(pmic->client);
	if (idx < 0) {
		dev_err(&pmic->client->dev, "Error getting voltage\n");
		data = idx;
		goto out;
	}

	/* Convert the data from chip to microvolts */
	data = ISL6271A_VOLTAGE_MIN + (ISL6271A_VOLTAGE_STEP * (idx & 0xf));

out:
	mutex_unlock(&pmic->mtx);
	return data;
}

static int isl6271a_set_voltage(struct regulator_dev *dev,
				int minuV, int maxuV,
				unsigned *selector)
{
	struct isl_pmic *pmic = rdev_get_drvdata(dev);
	int vsel, err, data;

	if (minuV < ISL6271A_VOLTAGE_MIN || minuV > ISL6271A_VOLTAGE_MAX)
		return -EINVAL;
	if (maxuV < ISL6271A_VOLTAGE_MIN || maxuV > ISL6271A_VOLTAGE_MAX)
		return -EINVAL;

	/* Align to 50000 mV */
	vsel = minuV - (minuV % ISL6271A_VOLTAGE_STEP);

	/* If the result fell out of [minuV,maxuV] range, put it back */
	if (vsel < minuV)
		vsel += ISL6271A_VOLTAGE_STEP;

	/* Convert the microvolts to data for the chip */
	data = (vsel - ISL6271A_VOLTAGE_MIN) / ISL6271A_VOLTAGE_STEP;

	*selector = data;

	mutex_lock(&pmic->mtx);

	err = i2c_smbus_write_byte(pmic->client, data);
	if (err < 0)
		dev_err(&pmic->client->dev, "Error setting voltage\n");

	mutex_unlock(&pmic->mtx);
	return err;
}

static int isl6271a_list_voltage(struct regulator_dev *dev, unsigned selector)
{
	return ISL6271A_VOLTAGE_MIN + (ISL6271A_VOLTAGE_STEP * selector);
}

static struct regulator_ops isl_core_ops = {
	.get_voltage	= isl6271a_get_voltage,
	.set_voltage	= isl6271a_set_voltage,
	.list_voltage	= isl6271a_list_voltage,
};

static int isl6271a_get_fixed_voltage(struct regulator_dev *dev)
{
	int id = rdev_get_id(dev);
	return (id == 1) ? 1100000 : 1300000;
}

static int isl6271a_list_fixed_voltage(struct regulator_dev *dev, unsigned selector)
{
	int id = rdev_get_id(dev);
	return (id == 1) ? 1100000 : 1300000;
}

static struct regulator_ops isl_fixed_ops = {
	.get_voltage	= isl6271a_get_fixed_voltage,
	.list_voltage	= isl6271a_list_fixed_voltage,
};

static struct regulator_desc isl_rd[] = {
	{
		.name		= "Core Buck",
		.id		= 0,
		.n_voltages	= 16,
		.ops		= &isl_core_ops,
		.type		= REGULATOR_VOLTAGE,
		.owner		= THIS_MODULE,
	}, {
		.name		= "LDO1",
		.id		= 1,
		.n_voltages	= 1,
		.ops		= &isl_fixed_ops,
		.type		= REGULATOR_VOLTAGE,
		.owner		= THIS_MODULE,
	}, {
		.name		= "LDO2",
		.id		= 2,
		.n_voltages	= 1,
		.ops		= &isl_fixed_ops,
		.type		= REGULATOR_VOLTAGE,
		.owner		= THIS_MODULE,
	},
};

static int __devinit isl6271a_probe(struct i2c_client *i2c,
				     const struct i2c_device_id *id)
{
	struct regulator_init_data *init_data	= i2c->dev.platform_data;
	struct isl_pmic *pmic;
	int err, i;

	if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
		return -EIO;

	if (!init_data) {
		dev_err(&i2c->dev, "no platform data supplied\n");
		return -EIO;
	}

	pmic = kzalloc(sizeof(struct isl_pmic), GFP_KERNEL);
	if (!pmic)
		return -ENOMEM;

	pmic->client = i2c;

	mutex_init(&pmic->mtx);

	for (i = 0; i < 3; i++) {
		pmic->rdev[i] = regulator_register(&isl_rd[i], &i2c->dev,
						init_data, pmic);
		if (IS_ERR(pmic->rdev[i])) {
			dev_err(&i2c->dev, "failed to register %s\n", id->name);
			err = PTR_ERR(pmic->rdev[i]);
			goto error;
		}
	}

	i2c_set_clientdata(i2c, pmic);

	return 0;

error:
	while (--i >= 0)
		regulator_unregister(pmic->rdev[i]);

	kfree(pmic);
	return err;
}

static int __devexit isl6271a_remove(struct i2c_client *i2c)
{
	struct isl_pmic *pmic = i2c_get_clientdata(i2c);
	int i;

	for (i = 0; i < 3; i++)
		regulator_unregister(pmic->rdev[i]);

	kfree(pmic);

	return 0;
}

static const struct i2c_device_id isl6271a_id[] = {
	{.name = "isl6271a", 0 },
	{ },
};

MODULE_DEVICE_TABLE(i2c, isl6271a_id);

static struct i2c_driver isl6271a_i2c_driver = {
	.driver = {
		.name = "isl6271a",
		.owner = THIS_MODULE,
	},
	.probe = isl6271a_probe,
	.remove = __devexit_p(isl6271a_remove),
	.id_table = isl6271a_id,
};

static int __init isl6271a_init(void)
{
	return i2c_add_driver(&isl6271a_i2c_driver);
}

static void __exit isl6271a_cleanup(void)
{
	i2c_del_driver(&isl6271a_i2c_driver);
}

subsys_initcall(isl6271a_init);
module_exit(isl6271a_cleanup);

MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
MODULE_DESCRIPTION("Intersil ISL6271A voltage regulator driver");
MODULE_LICENSE("GPL v2");
OpenPOWER on IntegriCloud