regulator: regulator test harness
[linux-2.6.git] / drivers / regulator / virtual.c
1 /*
2  * reg-virtual-consumer.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
14 #include <linux/err.h>
15 #include <linux/mutex.h>
16 #include <linux/platform_device.h>
17 #include <linux/regulator/consumer.h>
18
19 struct virtual_consumer_data {
20         struct mutex lock;
21         struct regulator *regulator;
22         int enabled;
23         int min_uV;
24         int max_uV;
25         int min_uA;
26         int max_uA;
27         unsigned int mode;
28 };
29
30 static void update_voltage_constraints(struct virtual_consumer_data *data)
31 {
32         int ret;
33
34         if (data->min_uV && data->max_uV
35             && data->min_uV <= data->max_uV) {
36                 ret = regulator_set_voltage(data->regulator,
37                                             data->min_uV, data->max_uV);
38                 if (ret != 0) {
39                         printk(KERN_ERR "regulator_set_voltage() failed: %d\n",
40                                ret);
41                         return;
42                 }
43         }
44
45         if (data->min_uV && data->max_uV && !data->enabled) {
46                 ret = regulator_enable(data->regulator);
47                 if (ret == 0)
48                         data->enabled = 1;
49                 else
50                         printk(KERN_ERR "regulator_enable() failed: %d\n",
51                                 ret);
52         }
53
54         if (!(data->min_uV && data->max_uV) && data->enabled) {
55                 ret = regulator_disable(data->regulator);
56                 if (ret == 0)
57                         data->enabled = 0;
58                 else
59                         printk(KERN_ERR "regulator_disable() failed: %d\n",
60                                 ret);
61         }
62 }
63
64 static void update_current_limit_constraints(struct virtual_consumer_data
65                                                 *data)
66 {
67         int ret;
68
69         if (data->max_uA
70             && data->min_uA <= data->max_uA) {
71                 ret = regulator_set_current_limit(data->regulator,
72                                         data->min_uA, data->max_uA);
73                 if (ret != 0) {
74                         pr_err("regulator_set_current_limit() failed: %d\n",
75                                ret);
76                         return;
77                 }
78         }
79
80         if (data->max_uA && !data->enabled) {
81                 ret = regulator_enable(data->regulator);
82                 if (ret == 0)
83                         data->enabled = 1;
84                 else
85                         printk(KERN_ERR "regulator_enable() failed: %d\n",
86                                 ret);
87         }
88
89         if (!(data->min_uA && data->max_uA) && data->enabled) {
90                 ret = regulator_disable(data->regulator);
91                 if (ret == 0)
92                         data->enabled = 0;
93                 else
94                         printk(KERN_ERR "regulator_disable() failed: %d\n",
95                                 ret);
96         }
97 }
98
99 static ssize_t show_min_uV(struct device *dev,
100                            struct device_attribute *attr, char *buf)
101 {
102         struct virtual_consumer_data *data = dev_get_drvdata(dev);
103         return sprintf(buf, "%d\n", data->min_uV);
104 }
105
106 static ssize_t set_min_uV(struct device *dev, struct device_attribute *attr,
107                           const char *buf, size_t count)
108 {
109         struct virtual_consumer_data *data = dev_get_drvdata(dev);
110         long val;
111
112         if (strict_strtol(buf, 10, &val) != 0)
113                 return count;
114
115         mutex_lock(&data->lock);
116
117         data->min_uV = val;
118         update_voltage_constraints(data);
119
120         mutex_unlock(&data->lock);
121
122         return count;
123 }
124
125 static ssize_t show_max_uV(struct device *dev,
126                            struct device_attribute *attr, char *buf)
127 {
128         struct virtual_consumer_data *data = dev_get_drvdata(dev);
129         return sprintf(buf, "%d\n", data->max_uV);
130 }
131
132 static ssize_t set_max_uV(struct device *dev, struct device_attribute *attr,
133                           const char *buf, size_t count)
134 {
135         struct virtual_consumer_data *data = dev_get_drvdata(dev);
136         long val;
137
138         if (strict_strtol(buf, 10, &val) != 0)
139                 return count;
140
141         mutex_lock(&data->lock);
142
143         data->max_uV = val;
144         update_voltage_constraints(data);
145
146         mutex_unlock(&data->lock);
147
148         return count;
149 }
150
151 static ssize_t show_min_uA(struct device *dev,
152                            struct device_attribute *attr, char *buf)
153 {
154         struct virtual_consumer_data *data = dev_get_drvdata(dev);
155         return sprintf(buf, "%d\n", data->min_uA);
156 }
157
158 static ssize_t set_min_uA(struct device *dev, struct device_attribute *attr,
159                           const char *buf, size_t count)
160 {
161         struct virtual_consumer_data *data = dev_get_drvdata(dev);
162         long val;
163
164         if (strict_strtol(buf, 10, &val) != 0)
165                 return count;
166
167         mutex_lock(&data->lock);
168
169         data->min_uA = val;
170         update_current_limit_constraints(data);
171
172         mutex_unlock(&data->lock);
173
174         return count;
175 }
176
177 static ssize_t show_max_uA(struct device *dev,
178                            struct device_attribute *attr, char *buf)
179 {
180         struct virtual_consumer_data *data = dev_get_drvdata(dev);
181         return sprintf(buf, "%d\n", data->max_uA);
182 }
183
184 static ssize_t set_max_uA(struct device *dev, struct device_attribute *attr,
185                           const char *buf, size_t count)
186 {
187         struct virtual_consumer_data *data = dev_get_drvdata(dev);
188         long val;
189
190         if (strict_strtol(buf, 10, &val) != 0)
191                 return count;
192
193         mutex_lock(&data->lock);
194
195         data->max_uA = val;
196         update_current_limit_constraints(data);
197
198         mutex_unlock(&data->lock);
199
200         return count;
201 }
202
203 static ssize_t show_mode(struct device *dev,
204                          struct device_attribute *attr, char *buf)
205 {
206         struct virtual_consumer_data *data = dev_get_drvdata(dev);
207
208         switch (data->mode) {
209         case REGULATOR_MODE_FAST:
210                 return sprintf(buf, "fast\n");
211         case REGULATOR_MODE_NORMAL:
212                 return sprintf(buf, "normal\n");
213         case REGULATOR_MODE_IDLE:
214                 return sprintf(buf, "idle\n");
215         case REGULATOR_MODE_STANDBY:
216                 return sprintf(buf, "standby\n");
217         default:
218                 return sprintf(buf, "unknown\n");
219         }
220 }
221
222 static ssize_t set_mode(struct device *dev, struct device_attribute *attr,
223                         const char *buf, size_t count)
224 {
225         struct virtual_consumer_data *data = dev_get_drvdata(dev);
226         unsigned int mode;
227         int ret;
228
229         if (strncmp(buf, "fast", strlen("fast")) == 0)
230                 mode = REGULATOR_MODE_FAST;
231         else if (strncmp(buf, "normal", strlen("normal")) == 0)
232                 mode = REGULATOR_MODE_NORMAL;
233         else if (strncmp(buf, "idle", strlen("idle")) == 0)
234                 mode = REGULATOR_MODE_IDLE;
235         else if (strncmp(buf, "standby", strlen("standby")) == 0)
236                 mode = REGULATOR_MODE_STANDBY;
237         else {
238                 dev_err(dev, "Configuring invalid mode\n");
239                 return count;
240         }
241
242         mutex_lock(&data->lock);
243         ret = regulator_set_mode(data->regulator, mode);
244         if (ret == 0)
245                 data->mode = mode;
246         else
247                 dev_err(dev, "Failed to configure mode: %d\n", ret);
248         mutex_unlock(&data->lock);
249
250         return count;
251 }
252
253 static DEVICE_ATTR(min_microvolts, 0666, show_min_uV, set_min_uV);
254 static DEVICE_ATTR(max_microvolts, 0666, show_max_uV, set_max_uV);
255 static DEVICE_ATTR(min_microamps, 0666, show_min_uA, set_min_uA);
256 static DEVICE_ATTR(max_microamps, 0666, show_max_uA, set_max_uA);
257 static DEVICE_ATTR(mode, 0666, show_mode, set_mode);
258
259 struct device_attribute *attributes[] = {
260         &dev_attr_min_microvolts,
261         &dev_attr_max_microvolts,
262         &dev_attr_min_microamps,
263         &dev_attr_max_microamps,
264         &dev_attr_mode,
265 };
266
267 static int regulator_virtual_consumer_probe(struct platform_device *pdev)
268 {
269         char *reg_id = pdev->dev.platform_data;
270         struct virtual_consumer_data *drvdata;
271         int ret, i;
272
273         drvdata = kzalloc(sizeof(struct virtual_consumer_data), GFP_KERNEL);
274         if (drvdata == NULL) {
275                 ret = -ENOMEM;
276                 goto err;
277         }
278
279         mutex_init(&drvdata->lock);
280
281         drvdata->regulator = regulator_get(&pdev->dev, reg_id);
282         if (IS_ERR(drvdata->regulator)) {
283                 ret = PTR_ERR(drvdata->regulator);
284                 goto err;
285         }
286
287         for (i = 0; i < ARRAY_SIZE(attributes); i++) {
288                 ret = device_create_file(&pdev->dev, attributes[i]);
289                 if (ret != 0)
290                         goto err;
291         }
292
293         drvdata->mode = regulator_get_mode(drvdata->regulator);
294
295         platform_set_drvdata(pdev, drvdata);
296
297         return 0;
298
299 err:
300         for (i = 0; i < ARRAY_SIZE(attributes); i++)
301                 device_remove_file(&pdev->dev, attributes[i]);
302         kfree(drvdata);
303         return ret;
304 }
305
306 static int regulator_virtual_consumer_remove(struct platform_device *pdev)
307 {
308         struct virtual_consumer_data *drvdata = platform_get_drvdata(pdev);
309         int i;
310
311         for (i = 0; i < ARRAY_SIZE(attributes); i++)
312                 device_remove_file(&pdev->dev, attributes[i]);
313         if (drvdata->enabled)
314                 regulator_disable(drvdata->regulator);
315         regulator_put(drvdata->regulator);
316
317         kfree(drvdata);
318
319         return 0;
320 }
321
322 static struct platform_driver regulator_virtual_consumer_driver = {
323         .probe          = regulator_virtual_consumer_probe,
324         .remove         = regulator_virtual_consumer_remove,
325         .driver         = {
326                 .name           = "reg-virt-consumer",
327         },
328 };
329
330
331 static int __init regulator_virtual_consumer_init(void)
332 {
333         return platform_driver_register(&regulator_virtual_consumer_driver);
334 }
335 module_init(regulator_virtual_consumer_init);
336
337 static void __exit regulator_virtual_consumer_exit(void)
338 {
339         platform_driver_unregister(&regulator_virtual_consumer_driver);
340 }
341 module_exit(regulator_virtual_consumer_exit);
342
343 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
344 MODULE_DESCRIPTION("Virtual regulator consumer");
345 MODULE_LICENSE("GPL");