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
|
/*
* Regulator driver for ST's PWM Regulators
*
* Copyright (C) 2014 - STMicroelectronics Inc.
*
* Author: Lee Jones <lee.jones@linaro.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
#include <linux/regulator/of_regulator.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/pwm.h>
#define ST_PWM_REG_PERIOD 8448
struct st_pwm_regulator_pdata {
const struct regulator_desc *desc;
struct st_pwm_voltages *duty_cycle_table;
};
struct st_pwm_regulator_data {
const struct st_pwm_regulator_pdata *pdata;
struct pwm_device *pwm;
bool enabled;
int state;
};
struct st_pwm_voltages {
unsigned int uV;
unsigned int dutycycle;
};
static int st_pwm_regulator_get_voltage(struct regulator_dev *dev)
{
struct st_pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
return drvdata->pdata->duty_cycle_table[drvdata->state].uV;
}
static int st_pwm_regulator_set_voltage_sel(struct regulator_dev *dev,
unsigned selector)
{
struct st_pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
int dutycycle;
int ret;
if (selector >= dev->desc->n_voltages)
return -EINVAL;
dutycycle = (ST_PWM_REG_PERIOD / 100) *
drvdata->pdata->duty_cycle_table[selector].dutycycle;
ret = pwm_config(drvdata->pwm, dutycycle, ST_PWM_REG_PERIOD);
if (ret) {
dev_err(&dev->dev, "Failed to configure PWM\n");
return ret;
}
drvdata->state = selector;
if (!drvdata->enabled) {
ret = pwm_enable(drvdata->pwm);
if (ret) {
dev_err(&dev->dev, "Failed to enable PWM\n");
return ret;
}
drvdata->enabled = true;
}
return 0;
}
static int st_pwm_regulator_list_voltage(struct regulator_dev *dev,
unsigned selector)
{
struct st_pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
if (selector >= dev->desc->n_voltages)
return -EINVAL;
return drvdata->pdata->duty_cycle_table[selector].uV;
}
static struct regulator_ops st_pwm_regulator_voltage_ops = {
.set_voltage_sel = st_pwm_regulator_set_voltage_sel,
.get_voltage = st_pwm_regulator_get_voltage,
.list_voltage = st_pwm_regulator_list_voltage,
.map_voltage = regulator_map_voltage_iterate,
};
static struct st_pwm_voltages b2105_duty_cycle_table[] = {
{ .uV = 1114000, .dutycycle = 0, },
{ .uV = 1095000, .dutycycle = 10, },
{ .uV = 1076000, .dutycycle = 20, },
{ .uV = 1056000, .dutycycle = 30, },
{ .uV = 1036000, .dutycycle = 40, },
{ .uV = 1016000, .dutycycle = 50, },
/* WARNING: Values above 50% duty-cycle cause boot failures. */
};
static const struct regulator_desc b2105_desc = {
.name = "b2105-pwm-regulator",
.ops = &st_pwm_regulator_voltage_ops,
.type = REGULATOR_VOLTAGE,
.owner = THIS_MODULE,
.n_voltages = ARRAY_SIZE(b2105_duty_cycle_table),
.supply_name = "pwm",
};
static const struct st_pwm_regulator_pdata b2105_info = {
.desc = &b2105_desc,
.duty_cycle_table = b2105_duty_cycle_table,
};
static struct of_device_id st_pwm_of_match[] = {
{ .compatible = "st,b2105-pwm-regulator", .data = &b2105_info, },
{ },
};
MODULE_DEVICE_TABLE(of, st_pwm_of_match);
static int st_pwm_regulator_probe(struct platform_device *pdev)
{
struct st_pwm_regulator_data *drvdata;
struct regulator_dev *regulator;
struct regulator_config config = { };
struct device_node *np = pdev->dev.of_node;
const struct of_device_id *of_match;
if (!np) {
dev_err(&pdev->dev, "Device Tree node missing\n");
return -EINVAL;
}
drvdata = devm_kzalloc(&pdev->dev, sizeof(*drvdata), GFP_KERNEL);
if (!drvdata)
return -ENOMEM;
of_match = of_match_device(st_pwm_of_match, &pdev->dev);
if (!of_match) {
dev_err(&pdev->dev, "failed to match of device\n");
return -ENODEV;
}
drvdata->pdata = of_match->data;
config.init_data = of_get_regulator_init_data(&pdev->dev, np);
if (!config.init_data)
return -ENOMEM;
config.of_node = np;
config.dev = &pdev->dev;
config.driver_data = drvdata;
drvdata->pwm = devm_pwm_get(&pdev->dev, NULL);
if (IS_ERR(drvdata->pwm)) {
dev_err(&pdev->dev, "Failed to get PWM\n");
return PTR_ERR(drvdata->pwm);
}
regulator = devm_regulator_register(&pdev->dev,
drvdata->pdata->desc, &config);
if (IS_ERR(regulator)) {
dev_err(&pdev->dev, "Failed to register regulator %s\n",
drvdata->pdata->desc->name);
return PTR_ERR(regulator);
}
return 0;
}
static struct platform_driver st_pwm_regulator_driver = {
.driver = {
.name = "st-pwm-regulator",
.owner = THIS_MODULE,
.of_match_table = of_match_ptr(st_pwm_of_match),
},
.probe = st_pwm_regulator_probe,
};
module_platform_driver(st_pwm_regulator_driver);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Lee Jones <lee.jones@linaro.org>");
MODULE_DESCRIPTION("ST PWM Regulator Driver");
MODULE_ALIAS("platform:st_pwm-regulator");
|
