Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/vapier...
[linux-2.6] / drivers / regulator / fixed.c
1 /*
2  * fixed.c
3  *
4  * Copyright 2008 Wolfson Microelectronics PLC.
5  *
6  * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License as
10  * published by the Free Software Foundation; either version 2 of the
11  * License, or (at your option) any later version.
12  *
13  * This is useful for systems with mixed controllable and
14  * non-controllable regulators, as well as for allowing testing on
15  * systems with no controllable regulators.
16  */
17
18 #include <linux/err.h>
19 #include <linux/mutex.h>
20 #include <linux/platform_device.h>
21 #include <linux/regulator/driver.h>
22 #include <linux/regulator/fixed.h>
23
24 struct fixed_voltage_data {
25         struct regulator_desc desc;
26         struct regulator_dev *dev;
27         int microvolts;
28 };
29
30 static int fixed_voltage_is_enabled(struct regulator_dev *dev)
31 {
32         return 1;
33 }
34
35 static int fixed_voltage_enable(struct regulator_dev *dev)
36 {
37         return 0;
38 }
39
40 static int fixed_voltage_get_voltage(struct regulator_dev *dev)
41 {
42         struct fixed_voltage_data *data = rdev_get_drvdata(dev);
43
44         return data->microvolts;
45 }
46
47 static int fixed_voltage_list_voltage(struct regulator_dev *dev,
48                                       unsigned selector)
49 {
50         struct fixed_voltage_data *data = rdev_get_drvdata(dev);
51
52         if (selector != 0)
53                 return -EINVAL;
54
55         return data->microvolts;
56 }
57
58 static struct regulator_ops fixed_voltage_ops = {
59         .is_enabled = fixed_voltage_is_enabled,
60         .enable = fixed_voltage_enable,
61         .get_voltage = fixed_voltage_get_voltage,
62         .list_voltage = fixed_voltage_list_voltage,
63 };
64
65 static int regulator_fixed_voltage_probe(struct platform_device *pdev)
66 {
67         struct fixed_voltage_config *config = pdev->dev.platform_data;
68         struct fixed_voltage_data *drvdata;
69         int ret;
70
71         drvdata = kzalloc(sizeof(struct fixed_voltage_data), GFP_KERNEL);
72         if (drvdata == NULL) {
73                 ret = -ENOMEM;
74                 goto err;
75         }
76
77         drvdata->desc.name = kstrdup(config->supply_name, GFP_KERNEL);
78         if (drvdata->desc.name == NULL) {
79                 ret = -ENOMEM;
80                 goto err;
81         }
82         drvdata->desc.type = REGULATOR_VOLTAGE;
83         drvdata->desc.owner = THIS_MODULE;
84         drvdata->desc.ops = &fixed_voltage_ops;
85         drvdata->desc.n_voltages = 1;
86
87         drvdata->microvolts = config->microvolts;
88
89         drvdata->dev = regulator_register(&drvdata->desc, &pdev->dev,
90                                           config->init_data, drvdata);
91         if (IS_ERR(drvdata->dev)) {
92                 ret = PTR_ERR(drvdata->dev);
93                 goto err_name;
94         }
95
96         platform_set_drvdata(pdev, drvdata);
97
98         dev_dbg(&pdev->dev, "%s supplying %duV\n", drvdata->desc.name,
99                 drvdata->microvolts);
100
101         return 0;
102
103 err_name:
104         kfree(drvdata->desc.name);
105 err:
106         kfree(drvdata);
107         return ret;
108 }
109
110 static int regulator_fixed_voltage_remove(struct platform_device *pdev)
111 {
112         struct fixed_voltage_data *drvdata = platform_get_drvdata(pdev);
113
114         regulator_unregister(drvdata->dev);
115         kfree(drvdata->desc.name);
116         kfree(drvdata);
117
118         return 0;
119 }
120
121 static struct platform_driver regulator_fixed_voltage_driver = {
122         .probe          = regulator_fixed_voltage_probe,
123         .remove         = regulator_fixed_voltage_remove,
124         .driver         = {
125                 .name           = "reg-fixed-voltage",
126         },
127 };
128
129 static int __init regulator_fixed_voltage_init(void)
130 {
131         return platform_driver_register(&regulator_fixed_voltage_driver);
132 }
133 subsys_initcall(regulator_fixed_voltage_init);
134
135 static void __exit regulator_fixed_voltage_exit(void)
136 {
137         platform_driver_unregister(&regulator_fixed_voltage_driver);
138 }
139 module_exit(regulator_fixed_voltage_exit);
140
141 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
142 MODULE_DESCRIPTION("Fixed voltage regulator");
143 MODULE_LICENSE("GPL");
144 MODULE_ALIAS("platform:reg-fixed-voltage");