sound: oss: rename local change_bits to avoid powerpc bitsops.h definition
[pandora-kernel.git] / drivers / regulator / userspace-consumer.c
1 /*
2  * userspace-consumer.c
3  *
4  * Copyright 2009 CompuLab, Ltd.
5  *
6  * Author: Mike Rapoport <mike@compulab.co.il>
7  *
8  * Based of virtual consumer driver:
9  *   Copyright 2008 Wolfson Microelectronics PLC.
10  *   Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
11  *
12  * This program is free software; you can redistribute it and/or
13  * modify it under the terms of the GNU General Public License as
14  * published by the Free Software Foundation; either version 2 of the
15  * License, or (at your option) any later version.
16  *
17  */
18
19 #include <linux/err.h>
20 #include <linux/mutex.h>
21 #include <linux/platform_device.h>
22 #include <linux/regulator/consumer.h>
23 #include <linux/regulator/userspace-consumer.h>
24 #include <linux/slab.h>
25
26 struct userspace_consumer_data {
27         const char *name;
28
29         struct mutex lock;
30         bool enabled;
31
32         int num_supplies;
33         struct regulator_bulk_data *supplies;
34 };
35
36 static ssize_t reg_show_name(struct device *dev,
37                           struct device_attribute *attr, char *buf)
38 {
39         struct userspace_consumer_data *data = dev_get_drvdata(dev);
40
41         return sprintf(buf, "%s\n", data->name);
42 }
43
44 static ssize_t reg_show_state(struct device *dev,
45                           struct device_attribute *attr, char *buf)
46 {
47         struct userspace_consumer_data *data = dev_get_drvdata(dev);
48
49         if (data->enabled)
50                 return sprintf(buf, "enabled\n");
51
52         return sprintf(buf, "disabled\n");
53 }
54
55 static ssize_t reg_set_state(struct device *dev, struct device_attribute *attr,
56                          const char *buf, size_t count)
57 {
58         struct userspace_consumer_data *data = dev_get_drvdata(dev);
59         bool enabled;
60         int ret;
61
62         /*
63          * sysfs_streq() doesn't need the \n's, but we add them so the strings
64          * will be shared with show_state(), above.
65          */
66         if (sysfs_streq(buf, "enabled\n") || sysfs_streq(buf, "1"))
67                 enabled = true;
68         else if (sysfs_streq(buf, "disabled\n") || sysfs_streq(buf, "0"))
69                 enabled = false;
70         else {
71                 dev_err(dev, "Configuring invalid mode\n");
72                 return count;
73         }
74
75         mutex_lock(&data->lock);
76         if (enabled != data->enabled) {
77                 if (enabled)
78                         ret = regulator_bulk_enable(data->num_supplies,
79                                                     data->supplies);
80                 else
81                         ret = regulator_bulk_disable(data->num_supplies,
82                                                      data->supplies);
83
84                 if (ret == 0)
85                         data->enabled = enabled;
86                 else
87                         dev_err(dev, "Failed to configure state: %d\n", ret);
88         }
89         mutex_unlock(&data->lock);
90
91         return count;
92 }
93
94 static DEVICE_ATTR(name, 0444, reg_show_name, NULL);
95 static DEVICE_ATTR(state, 0644, reg_show_state, reg_set_state);
96
97 static struct attribute *attributes[] = {
98         &dev_attr_name.attr,
99         &dev_attr_state.attr,
100         NULL,
101 };
102
103 static const struct attribute_group attr_group = {
104         .attrs  = attributes,
105 };
106
107 static int regulator_userspace_consumer_probe(struct platform_device *pdev)
108 {
109         struct regulator_userspace_consumer_data *pdata;
110         struct userspace_consumer_data *drvdata;
111         int ret;
112
113         pdata = pdev->dev.platform_data;
114         if (!pdata)
115                 return -EINVAL;
116
117         drvdata = kzalloc(sizeof(struct userspace_consumer_data), GFP_KERNEL);
118         if (drvdata == NULL)
119                 return -ENOMEM;
120
121         drvdata->name = pdata->name;
122         drvdata->num_supplies = pdata->num_supplies;
123         drvdata->supplies = pdata->supplies;
124
125         mutex_init(&drvdata->lock);
126
127         ret = regulator_bulk_get(&pdev->dev, drvdata->num_supplies,
128                                  drvdata->supplies);
129         if (ret) {
130                 dev_err(&pdev->dev, "Failed to get supplies: %d\n", ret);
131                 goto err_alloc_supplies;
132         }
133
134         ret = sysfs_create_group(&pdev->dev.kobj, &attr_group);
135         if (ret != 0)
136                 goto err_create_attrs;
137
138         if (pdata->init_on) {
139                 ret = regulator_bulk_enable(drvdata->num_supplies,
140                                             drvdata->supplies);
141                 if (ret) {
142                         dev_err(&pdev->dev,
143                                 "Failed to set initial state: %d\n", ret);
144                         goto err_enable;
145                 }
146         }
147
148         drvdata->enabled = pdata->init_on;
149         platform_set_drvdata(pdev, drvdata);
150
151         return 0;
152
153 err_enable:
154         sysfs_remove_group(&pdev->dev.kobj, &attr_group);
155
156 err_create_attrs:
157         regulator_bulk_free(drvdata->num_supplies, drvdata->supplies);
158
159 err_alloc_supplies:
160         kfree(drvdata);
161         return ret;
162 }
163
164 static int regulator_userspace_consumer_remove(struct platform_device *pdev)
165 {
166         struct userspace_consumer_data *data = platform_get_drvdata(pdev);
167
168         sysfs_remove_group(&pdev->dev.kobj, &attr_group);
169
170         if (data->enabled)
171                 regulator_bulk_disable(data->num_supplies, data->supplies);
172
173         regulator_bulk_free(data->num_supplies, data->supplies);
174         kfree(data);
175
176         return 0;
177 }
178
179 static struct platform_driver regulator_userspace_consumer_driver = {
180         .probe          = regulator_userspace_consumer_probe,
181         .remove         = regulator_userspace_consumer_remove,
182         .driver         = {
183                 .name           = "reg-userspace-consumer",
184         },
185 };
186
187
188 static int __init regulator_userspace_consumer_init(void)
189 {
190         return platform_driver_register(&regulator_userspace_consumer_driver);
191 }
192 module_init(regulator_userspace_consumer_init);
193
194 static void __exit regulator_userspace_consumer_exit(void)
195 {
196         platform_driver_unregister(&regulator_userspace_consumer_driver);
197 }
198 module_exit(regulator_userspace_consumer_exit);
199
200 MODULE_AUTHOR("Mike Rapoport <mike@compulab.co.il>");
201 MODULE_DESCRIPTION("Userspace consumer for voltage and current regulators");
202 MODULE_LICENSE("GPL");