Merge branch 'for-2.6.30' of git://linux-nfs.org/~bfields/linux
[pandora-kernel.git] / drivers / regulator / core.c
1 /*
2  * core.c  --  Voltage/Current Regulator framework.
3  *
4  * Copyright 2007, 2008 Wolfson Microelectronics PLC.
5  * Copyright 2008 SlimLogic Ltd.
6  *
7  * Author: Liam Girdwood <lrg@slimlogic.co.uk>
8  *
9  *  This program is free software; you can redistribute  it and/or modify it
10  *  under  the terms of  the GNU General  Public License as published by the
11  *  Free Software Foundation;  either version 2 of the  License, or (at your
12  *  option) any later version.
13  *
14  */
15
16 #include <linux/kernel.h>
17 #include <linux/init.h>
18 #include <linux/device.h>
19 #include <linux/err.h>
20 #include <linux/mutex.h>
21 #include <linux/suspend.h>
22 #include <linux/regulator/consumer.h>
23 #include <linux/regulator/driver.h>
24 #include <linux/regulator/machine.h>
25
26 #define REGULATOR_VERSION "0.5"
27
28 static DEFINE_MUTEX(regulator_list_mutex);
29 static LIST_HEAD(regulator_list);
30 static LIST_HEAD(regulator_map_list);
31 static int has_full_constraints;
32
33 /*
34  * struct regulator_map
35  *
36  * Used to provide symbolic supply names to devices.
37  */
38 struct regulator_map {
39         struct list_head list;
40         struct device *dev;
41         const char *supply;
42         struct regulator_dev *regulator;
43 };
44
45 /*
46  * struct regulator
47  *
48  * One for each consumer device.
49  */
50 struct regulator {
51         struct device *dev;
52         struct list_head list;
53         int uA_load;
54         int min_uV;
55         int max_uV;
56         char *supply_name;
57         struct device_attribute dev_attr;
58         struct regulator_dev *rdev;
59 };
60
61 static int _regulator_is_enabled(struct regulator_dev *rdev);
62 static int _regulator_disable(struct regulator_dev *rdev);
63 static int _regulator_get_voltage(struct regulator_dev *rdev);
64 static int _regulator_get_current_limit(struct regulator_dev *rdev);
65 static unsigned int _regulator_get_mode(struct regulator_dev *rdev);
66 static void _notifier_call_chain(struct regulator_dev *rdev,
67                                   unsigned long event, void *data);
68
69 /* gets the regulator for a given consumer device */
70 static struct regulator *get_device_regulator(struct device *dev)
71 {
72         struct regulator *regulator = NULL;
73         struct regulator_dev *rdev;
74
75         mutex_lock(&regulator_list_mutex);
76         list_for_each_entry(rdev, &regulator_list, list) {
77                 mutex_lock(&rdev->mutex);
78                 list_for_each_entry(regulator, &rdev->consumer_list, list) {
79                         if (regulator->dev == dev) {
80                                 mutex_unlock(&rdev->mutex);
81                                 mutex_unlock(&regulator_list_mutex);
82                                 return regulator;
83                         }
84                 }
85                 mutex_unlock(&rdev->mutex);
86         }
87         mutex_unlock(&regulator_list_mutex);
88         return NULL;
89 }
90
91 /* Platform voltage constraint check */
92 static int regulator_check_voltage(struct regulator_dev *rdev,
93                                    int *min_uV, int *max_uV)
94 {
95         BUG_ON(*min_uV > *max_uV);
96
97         if (!rdev->constraints) {
98                 printk(KERN_ERR "%s: no constraints for %s\n", __func__,
99                        rdev->desc->name);
100                 return -ENODEV;
101         }
102         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
103                 printk(KERN_ERR "%s: operation not allowed for %s\n",
104                        __func__, rdev->desc->name);
105                 return -EPERM;
106         }
107
108         if (*max_uV > rdev->constraints->max_uV)
109                 *max_uV = rdev->constraints->max_uV;
110         if (*min_uV < rdev->constraints->min_uV)
111                 *min_uV = rdev->constraints->min_uV;
112
113         if (*min_uV > *max_uV)
114                 return -EINVAL;
115
116         return 0;
117 }
118
119 /* current constraint check */
120 static int regulator_check_current_limit(struct regulator_dev *rdev,
121                                         int *min_uA, int *max_uA)
122 {
123         BUG_ON(*min_uA > *max_uA);
124
125         if (!rdev->constraints) {
126                 printk(KERN_ERR "%s: no constraints for %s\n", __func__,
127                        rdev->desc->name);
128                 return -ENODEV;
129         }
130         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_CURRENT)) {
131                 printk(KERN_ERR "%s: operation not allowed for %s\n",
132                        __func__, rdev->desc->name);
133                 return -EPERM;
134         }
135
136         if (*max_uA > rdev->constraints->max_uA)
137                 *max_uA = rdev->constraints->max_uA;
138         if (*min_uA < rdev->constraints->min_uA)
139                 *min_uA = rdev->constraints->min_uA;
140
141         if (*min_uA > *max_uA)
142                 return -EINVAL;
143
144         return 0;
145 }
146
147 /* operating mode constraint check */
148 static int regulator_check_mode(struct regulator_dev *rdev, int mode)
149 {
150         switch (mode) {
151         case REGULATOR_MODE_FAST:
152         case REGULATOR_MODE_NORMAL:
153         case REGULATOR_MODE_IDLE:
154         case REGULATOR_MODE_STANDBY:
155                 break;
156         default:
157                 return -EINVAL;
158         }
159
160         if (!rdev->constraints) {
161                 printk(KERN_ERR "%s: no constraints for %s\n", __func__,
162                        rdev->desc->name);
163                 return -ENODEV;
164         }
165         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_MODE)) {
166                 printk(KERN_ERR "%s: operation not allowed for %s\n",
167                        __func__, rdev->desc->name);
168                 return -EPERM;
169         }
170         if (!(rdev->constraints->valid_modes_mask & mode)) {
171                 printk(KERN_ERR "%s: invalid mode %x for %s\n",
172                        __func__, mode, rdev->desc->name);
173                 return -EINVAL;
174         }
175         return 0;
176 }
177
178 /* dynamic regulator mode switching constraint check */
179 static int regulator_check_drms(struct regulator_dev *rdev)
180 {
181         if (!rdev->constraints) {
182                 printk(KERN_ERR "%s: no constraints for %s\n", __func__,
183                        rdev->desc->name);
184                 return -ENODEV;
185         }
186         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS)) {
187                 printk(KERN_ERR "%s: operation not allowed for %s\n",
188                        __func__, rdev->desc->name);
189                 return -EPERM;
190         }
191         return 0;
192 }
193
194 static ssize_t device_requested_uA_show(struct device *dev,
195                              struct device_attribute *attr, char *buf)
196 {
197         struct regulator *regulator;
198
199         regulator = get_device_regulator(dev);
200         if (regulator == NULL)
201                 return 0;
202
203         return sprintf(buf, "%d\n", regulator->uA_load);
204 }
205
206 static ssize_t regulator_uV_show(struct device *dev,
207                                 struct device_attribute *attr, char *buf)
208 {
209         struct regulator_dev *rdev = dev_get_drvdata(dev);
210         ssize_t ret;
211
212         mutex_lock(&rdev->mutex);
213         ret = sprintf(buf, "%d\n", _regulator_get_voltage(rdev));
214         mutex_unlock(&rdev->mutex);
215
216         return ret;
217 }
218 static DEVICE_ATTR(microvolts, 0444, regulator_uV_show, NULL);
219
220 static ssize_t regulator_uA_show(struct device *dev,
221                                 struct device_attribute *attr, char *buf)
222 {
223         struct regulator_dev *rdev = dev_get_drvdata(dev);
224
225         return sprintf(buf, "%d\n", _regulator_get_current_limit(rdev));
226 }
227 static DEVICE_ATTR(microamps, 0444, regulator_uA_show, NULL);
228
229 static ssize_t regulator_name_show(struct device *dev,
230                              struct device_attribute *attr, char *buf)
231 {
232         struct regulator_dev *rdev = dev_get_drvdata(dev);
233         const char *name;
234
235         if (rdev->constraints->name)
236                 name = rdev->constraints->name;
237         else if (rdev->desc->name)
238                 name = rdev->desc->name;
239         else
240                 name = "";
241
242         return sprintf(buf, "%s\n", name);
243 }
244
245 static ssize_t regulator_print_opmode(char *buf, int mode)
246 {
247         switch (mode) {
248         case REGULATOR_MODE_FAST:
249                 return sprintf(buf, "fast\n");
250         case REGULATOR_MODE_NORMAL:
251                 return sprintf(buf, "normal\n");
252         case REGULATOR_MODE_IDLE:
253                 return sprintf(buf, "idle\n");
254         case REGULATOR_MODE_STANDBY:
255                 return sprintf(buf, "standby\n");
256         }
257         return sprintf(buf, "unknown\n");
258 }
259
260 static ssize_t regulator_opmode_show(struct device *dev,
261                                     struct device_attribute *attr, char *buf)
262 {
263         struct regulator_dev *rdev = dev_get_drvdata(dev);
264
265         return regulator_print_opmode(buf, _regulator_get_mode(rdev));
266 }
267 static DEVICE_ATTR(opmode, 0444, regulator_opmode_show, NULL);
268
269 static ssize_t regulator_print_state(char *buf, int state)
270 {
271         if (state > 0)
272                 return sprintf(buf, "enabled\n");
273         else if (state == 0)
274                 return sprintf(buf, "disabled\n");
275         else
276                 return sprintf(buf, "unknown\n");
277 }
278
279 static ssize_t regulator_state_show(struct device *dev,
280                                    struct device_attribute *attr, char *buf)
281 {
282         struct regulator_dev *rdev = dev_get_drvdata(dev);
283
284         return regulator_print_state(buf, _regulator_is_enabled(rdev));
285 }
286 static DEVICE_ATTR(state, 0444, regulator_state_show, NULL);
287
288 static ssize_t regulator_status_show(struct device *dev,
289                                    struct device_attribute *attr, char *buf)
290 {
291         struct regulator_dev *rdev = dev_get_drvdata(dev);
292         int status;
293         char *label;
294
295         status = rdev->desc->ops->get_status(rdev);
296         if (status < 0)
297                 return status;
298
299         switch (status) {
300         case REGULATOR_STATUS_OFF:
301                 label = "off";
302                 break;
303         case REGULATOR_STATUS_ON:
304                 label = "on";
305                 break;
306         case REGULATOR_STATUS_ERROR:
307                 label = "error";
308                 break;
309         case REGULATOR_STATUS_FAST:
310                 label = "fast";
311                 break;
312         case REGULATOR_STATUS_NORMAL:
313                 label = "normal";
314                 break;
315         case REGULATOR_STATUS_IDLE:
316                 label = "idle";
317                 break;
318         case REGULATOR_STATUS_STANDBY:
319                 label = "standby";
320                 break;
321         default:
322                 return -ERANGE;
323         }
324
325         return sprintf(buf, "%s\n", label);
326 }
327 static DEVICE_ATTR(status, 0444, regulator_status_show, NULL);
328
329 static ssize_t regulator_min_uA_show(struct device *dev,
330                                     struct device_attribute *attr, char *buf)
331 {
332         struct regulator_dev *rdev = dev_get_drvdata(dev);
333
334         if (!rdev->constraints)
335                 return sprintf(buf, "constraint not defined\n");
336
337         return sprintf(buf, "%d\n", rdev->constraints->min_uA);
338 }
339 static DEVICE_ATTR(min_microamps, 0444, regulator_min_uA_show, NULL);
340
341 static ssize_t regulator_max_uA_show(struct device *dev,
342                                     struct device_attribute *attr, char *buf)
343 {
344         struct regulator_dev *rdev = dev_get_drvdata(dev);
345
346         if (!rdev->constraints)
347                 return sprintf(buf, "constraint not defined\n");
348
349         return sprintf(buf, "%d\n", rdev->constraints->max_uA);
350 }
351 static DEVICE_ATTR(max_microamps, 0444, regulator_max_uA_show, NULL);
352
353 static ssize_t regulator_min_uV_show(struct device *dev,
354                                     struct device_attribute *attr, char *buf)
355 {
356         struct regulator_dev *rdev = dev_get_drvdata(dev);
357
358         if (!rdev->constraints)
359                 return sprintf(buf, "constraint not defined\n");
360
361         return sprintf(buf, "%d\n", rdev->constraints->min_uV);
362 }
363 static DEVICE_ATTR(min_microvolts, 0444, regulator_min_uV_show, NULL);
364
365 static ssize_t regulator_max_uV_show(struct device *dev,
366                                     struct device_attribute *attr, char *buf)
367 {
368         struct regulator_dev *rdev = dev_get_drvdata(dev);
369
370         if (!rdev->constraints)
371                 return sprintf(buf, "constraint not defined\n");
372
373         return sprintf(buf, "%d\n", rdev->constraints->max_uV);
374 }
375 static DEVICE_ATTR(max_microvolts, 0444, regulator_max_uV_show, NULL);
376
377 static ssize_t regulator_total_uA_show(struct device *dev,
378                                       struct device_attribute *attr, char *buf)
379 {
380         struct regulator_dev *rdev = dev_get_drvdata(dev);
381         struct regulator *regulator;
382         int uA = 0;
383
384         mutex_lock(&rdev->mutex);
385         list_for_each_entry(regulator, &rdev->consumer_list, list)
386             uA += regulator->uA_load;
387         mutex_unlock(&rdev->mutex);
388         return sprintf(buf, "%d\n", uA);
389 }
390 static DEVICE_ATTR(requested_microamps, 0444, regulator_total_uA_show, NULL);
391
392 static ssize_t regulator_num_users_show(struct device *dev,
393                                       struct device_attribute *attr, char *buf)
394 {
395         struct regulator_dev *rdev = dev_get_drvdata(dev);
396         return sprintf(buf, "%d\n", rdev->use_count);
397 }
398
399 static ssize_t regulator_type_show(struct device *dev,
400                                   struct device_attribute *attr, char *buf)
401 {
402         struct regulator_dev *rdev = dev_get_drvdata(dev);
403
404         switch (rdev->desc->type) {
405         case REGULATOR_VOLTAGE:
406                 return sprintf(buf, "voltage\n");
407         case REGULATOR_CURRENT:
408                 return sprintf(buf, "current\n");
409         }
410         return sprintf(buf, "unknown\n");
411 }
412
413 static ssize_t regulator_suspend_mem_uV_show(struct device *dev,
414                                 struct device_attribute *attr, char *buf)
415 {
416         struct regulator_dev *rdev = dev_get_drvdata(dev);
417
418         return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
419 }
420 static DEVICE_ATTR(suspend_mem_microvolts, 0444,
421                 regulator_suspend_mem_uV_show, NULL);
422
423 static ssize_t regulator_suspend_disk_uV_show(struct device *dev,
424                                 struct device_attribute *attr, char *buf)
425 {
426         struct regulator_dev *rdev = dev_get_drvdata(dev);
427
428         return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
429 }
430 static DEVICE_ATTR(suspend_disk_microvolts, 0444,
431                 regulator_suspend_disk_uV_show, NULL);
432
433 static ssize_t regulator_suspend_standby_uV_show(struct device *dev,
434                                 struct device_attribute *attr, char *buf)
435 {
436         struct regulator_dev *rdev = dev_get_drvdata(dev);
437
438         return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
439 }
440 static DEVICE_ATTR(suspend_standby_microvolts, 0444,
441                 regulator_suspend_standby_uV_show, NULL);
442
443 static ssize_t regulator_suspend_mem_mode_show(struct device *dev,
444                                 struct device_attribute *attr, char *buf)
445 {
446         struct regulator_dev *rdev = dev_get_drvdata(dev);
447
448         return regulator_print_opmode(buf,
449                 rdev->constraints->state_mem.mode);
450 }
451 static DEVICE_ATTR(suspend_mem_mode, 0444,
452                 regulator_suspend_mem_mode_show, NULL);
453
454 static ssize_t regulator_suspend_disk_mode_show(struct device *dev,
455                                 struct device_attribute *attr, char *buf)
456 {
457         struct regulator_dev *rdev = dev_get_drvdata(dev);
458
459         return regulator_print_opmode(buf,
460                 rdev->constraints->state_disk.mode);
461 }
462 static DEVICE_ATTR(suspend_disk_mode, 0444,
463                 regulator_suspend_disk_mode_show, NULL);
464
465 static ssize_t regulator_suspend_standby_mode_show(struct device *dev,
466                                 struct device_attribute *attr, char *buf)
467 {
468         struct regulator_dev *rdev = dev_get_drvdata(dev);
469
470         return regulator_print_opmode(buf,
471                 rdev->constraints->state_standby.mode);
472 }
473 static DEVICE_ATTR(suspend_standby_mode, 0444,
474                 regulator_suspend_standby_mode_show, NULL);
475
476 static ssize_t regulator_suspend_mem_state_show(struct device *dev,
477                                    struct device_attribute *attr, char *buf)
478 {
479         struct regulator_dev *rdev = dev_get_drvdata(dev);
480
481         return regulator_print_state(buf,
482                         rdev->constraints->state_mem.enabled);
483 }
484 static DEVICE_ATTR(suspend_mem_state, 0444,
485                 regulator_suspend_mem_state_show, NULL);
486
487 static ssize_t regulator_suspend_disk_state_show(struct device *dev,
488                                    struct device_attribute *attr, char *buf)
489 {
490         struct regulator_dev *rdev = dev_get_drvdata(dev);
491
492         return regulator_print_state(buf,
493                         rdev->constraints->state_disk.enabled);
494 }
495 static DEVICE_ATTR(suspend_disk_state, 0444,
496                 regulator_suspend_disk_state_show, NULL);
497
498 static ssize_t regulator_suspend_standby_state_show(struct device *dev,
499                                    struct device_attribute *attr, char *buf)
500 {
501         struct regulator_dev *rdev = dev_get_drvdata(dev);
502
503         return regulator_print_state(buf,
504                         rdev->constraints->state_standby.enabled);
505 }
506 static DEVICE_ATTR(suspend_standby_state, 0444,
507                 regulator_suspend_standby_state_show, NULL);
508
509
510 /*
511  * These are the only attributes are present for all regulators.
512  * Other attributes are a function of regulator functionality.
513  */
514 static struct device_attribute regulator_dev_attrs[] = {
515         __ATTR(name, 0444, regulator_name_show, NULL),
516         __ATTR(num_users, 0444, regulator_num_users_show, NULL),
517         __ATTR(type, 0444, regulator_type_show, NULL),
518         __ATTR_NULL,
519 };
520
521 static void regulator_dev_release(struct device *dev)
522 {
523         struct regulator_dev *rdev = dev_get_drvdata(dev);
524         kfree(rdev);
525 }
526
527 static struct class regulator_class = {
528         .name = "regulator",
529         .dev_release = regulator_dev_release,
530         .dev_attrs = regulator_dev_attrs,
531 };
532
533 /* Calculate the new optimum regulator operating mode based on the new total
534  * consumer load. All locks held by caller */
535 static void drms_uA_update(struct regulator_dev *rdev)
536 {
537         struct regulator *sibling;
538         int current_uA = 0, output_uV, input_uV, err;
539         unsigned int mode;
540
541         err = regulator_check_drms(rdev);
542         if (err < 0 || !rdev->desc->ops->get_optimum_mode ||
543             !rdev->desc->ops->get_voltage || !rdev->desc->ops->set_mode);
544         return;
545
546         /* get output voltage */
547         output_uV = rdev->desc->ops->get_voltage(rdev);
548         if (output_uV <= 0)
549                 return;
550
551         /* get input voltage */
552         if (rdev->supply && rdev->supply->desc->ops->get_voltage)
553                 input_uV = rdev->supply->desc->ops->get_voltage(rdev->supply);
554         else
555                 input_uV = rdev->constraints->input_uV;
556         if (input_uV <= 0)
557                 return;
558
559         /* calc total requested load */
560         list_for_each_entry(sibling, &rdev->consumer_list, list)
561             current_uA += sibling->uA_load;
562
563         /* now get the optimum mode for our new total regulator load */
564         mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
565                                                   output_uV, current_uA);
566
567         /* check the new mode is allowed */
568         err = regulator_check_mode(rdev, mode);
569         if (err == 0)
570                 rdev->desc->ops->set_mode(rdev, mode);
571 }
572
573 static int suspend_set_state(struct regulator_dev *rdev,
574         struct regulator_state *rstate)
575 {
576         int ret = 0;
577
578         /* enable & disable are mandatory for suspend control */
579         if (!rdev->desc->ops->set_suspend_enable ||
580                 !rdev->desc->ops->set_suspend_disable) {
581                 printk(KERN_ERR "%s: no way to set suspend state\n",
582                         __func__);
583                 return -EINVAL;
584         }
585
586         if (rstate->enabled)
587                 ret = rdev->desc->ops->set_suspend_enable(rdev);
588         else
589                 ret = rdev->desc->ops->set_suspend_disable(rdev);
590         if (ret < 0) {
591                 printk(KERN_ERR "%s: failed to enabled/disable\n", __func__);
592                 return ret;
593         }
594
595         if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
596                 ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
597                 if (ret < 0) {
598                         printk(KERN_ERR "%s: failed to set voltage\n",
599                                 __func__);
600                         return ret;
601                 }
602         }
603
604         if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
605                 ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
606                 if (ret < 0) {
607                         printk(KERN_ERR "%s: failed to set mode\n", __func__);
608                         return ret;
609                 }
610         }
611         return ret;
612 }
613
614 /* locks held by caller */
615 static int suspend_prepare(struct regulator_dev *rdev, suspend_state_t state)
616 {
617         if (!rdev->constraints)
618                 return -EINVAL;
619
620         switch (state) {
621         case PM_SUSPEND_STANDBY:
622                 return suspend_set_state(rdev,
623                         &rdev->constraints->state_standby);
624         case PM_SUSPEND_MEM:
625                 return suspend_set_state(rdev,
626                         &rdev->constraints->state_mem);
627         case PM_SUSPEND_MAX:
628                 return suspend_set_state(rdev,
629                         &rdev->constraints->state_disk);
630         default:
631                 return -EINVAL;
632         }
633 }
634
635 static void print_constraints(struct regulator_dev *rdev)
636 {
637         struct regulation_constraints *constraints = rdev->constraints;
638         char buf[80];
639         int count;
640
641         if (rdev->desc->type == REGULATOR_VOLTAGE) {
642                 if (constraints->min_uV == constraints->max_uV)
643                         count = sprintf(buf, "%d mV ",
644                                         constraints->min_uV / 1000);
645                 else
646                         count = sprintf(buf, "%d <--> %d mV ",
647                                         constraints->min_uV / 1000,
648                                         constraints->max_uV / 1000);
649         } else {
650                 if (constraints->min_uA == constraints->max_uA)
651                         count = sprintf(buf, "%d mA ",
652                                         constraints->min_uA / 1000);
653                 else
654                         count = sprintf(buf, "%d <--> %d mA ",
655                                         constraints->min_uA / 1000,
656                                         constraints->max_uA / 1000);
657         }
658         if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
659                 count += sprintf(buf + count, "fast ");
660         if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
661                 count += sprintf(buf + count, "normal ");
662         if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
663                 count += sprintf(buf + count, "idle ");
664         if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
665                 count += sprintf(buf + count, "standby");
666
667         printk(KERN_INFO "regulator: %s: %s\n", rdev->desc->name, buf);
668 }
669
670 /**
671  * set_machine_constraints - sets regulator constraints
672  * @rdev: regulator source
673  * @constraints: constraints to apply
674  *
675  * Allows platform initialisation code to define and constrain
676  * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
677  * Constraints *must* be set by platform code in order for some
678  * regulator operations to proceed i.e. set_voltage, set_current_limit,
679  * set_mode.
680  */
681 static int set_machine_constraints(struct regulator_dev *rdev,
682         struct regulation_constraints *constraints)
683 {
684         int ret = 0;
685         const char *name;
686         struct regulator_ops *ops = rdev->desc->ops;
687
688         if (constraints->name)
689                 name = constraints->name;
690         else if (rdev->desc->name)
691                 name = rdev->desc->name;
692         else
693                 name = "regulator";
694
695         /* constrain machine-level voltage specs to fit
696          * the actual range supported by this regulator.
697          */
698         if (ops->list_voltage && rdev->desc->n_voltages) {
699                 int     count = rdev->desc->n_voltages;
700                 int     i;
701                 int     min_uV = INT_MAX;
702                 int     max_uV = INT_MIN;
703                 int     cmin = constraints->min_uV;
704                 int     cmax = constraints->max_uV;
705
706                 /* it's safe to autoconfigure fixed-voltage supplies */
707                 if (count == 1 && !cmin) {
708                         cmin = INT_MIN;
709                         cmax = INT_MAX;
710                 }
711
712                 /* voltage constraints are optional */
713                 if ((cmin == 0) && (cmax == 0))
714                         goto out;
715
716                 /* else require explicit machine-level constraints */
717                 if (cmin <= 0 || cmax <= 0 || cmax < cmin) {
718                         pr_err("%s: %s '%s' voltage constraints\n",
719                                        __func__, "invalid", name);
720                         ret = -EINVAL;
721                         goto out;
722                 }
723
724                 /* initial: [cmin..cmax] valid, [min_uV..max_uV] not */
725                 for (i = 0; i < count; i++) {
726                         int     value;
727
728                         value = ops->list_voltage(rdev, i);
729                         if (value <= 0)
730                                 continue;
731
732                         /* maybe adjust [min_uV..max_uV] */
733                         if (value >= cmin && value < min_uV)
734                                 min_uV = value;
735                         if (value <= cmax && value > max_uV)
736                                 max_uV = value;
737                 }
738
739                 /* final: [min_uV..max_uV] valid iff constraints valid */
740                 if (max_uV < min_uV) {
741                         pr_err("%s: %s '%s' voltage constraints\n",
742                                        __func__, "unsupportable", name);
743                         ret = -EINVAL;
744                         goto out;
745                 }
746
747                 /* use regulator's subset of machine constraints */
748                 if (constraints->min_uV < min_uV) {
749                         pr_debug("%s: override '%s' %s, %d -> %d\n",
750                                        __func__, name, "min_uV",
751                                         constraints->min_uV, min_uV);
752                         constraints->min_uV = min_uV;
753                 }
754                 if (constraints->max_uV > max_uV) {
755                         pr_debug("%s: override '%s' %s, %d -> %d\n",
756                                        __func__, name, "max_uV",
757                                         constraints->max_uV, max_uV);
758                         constraints->max_uV = max_uV;
759                 }
760         }
761
762         rdev->constraints = constraints;
763
764         /* do we need to apply the constraint voltage */
765         if (rdev->constraints->apply_uV &&
766                 rdev->constraints->min_uV == rdev->constraints->max_uV &&
767                 ops->set_voltage) {
768                 ret = ops->set_voltage(rdev,
769                         rdev->constraints->min_uV, rdev->constraints->max_uV);
770                         if (ret < 0) {
771                                 printk(KERN_ERR "%s: failed to apply %duV constraint to %s\n",
772                                        __func__,
773                                        rdev->constraints->min_uV, name);
774                                 rdev->constraints = NULL;
775                                 goto out;
776                         }
777         }
778
779         /* do we need to setup our suspend state */
780         if (constraints->initial_state) {
781                 ret = suspend_prepare(rdev, constraints->initial_state);
782                 if (ret < 0) {
783                         printk(KERN_ERR "%s: failed to set suspend state for %s\n",
784                                __func__, name);
785                         rdev->constraints = NULL;
786                         goto out;
787                 }
788         }
789
790         if (constraints->initial_mode) {
791                 if (!ops->set_mode) {
792                         printk(KERN_ERR "%s: no set_mode operation for %s\n",
793                                __func__, name);
794                         ret = -EINVAL;
795                         goto out;
796                 }
797
798                 ret = ops->set_mode(rdev, constraints->initial_mode);
799                 if (ret < 0) {
800                         printk(KERN_ERR
801                                "%s: failed to set initial mode for %s: %d\n",
802                                __func__, name, ret);
803                         goto out;
804                 }
805         }
806
807         /* If the constraints say the regulator should be on at this point
808          * and we have control then make sure it is enabled.
809          */
810         if ((constraints->always_on || constraints->boot_on) && ops->enable) {
811                 ret = ops->enable(rdev);
812                 if (ret < 0) {
813                         printk(KERN_ERR "%s: failed to enable %s\n",
814                                __func__, name);
815                         rdev->constraints = NULL;
816                         goto out;
817                 }
818         }
819
820         print_constraints(rdev);
821 out:
822         return ret;
823 }
824
825 /**
826  * set_supply - set regulator supply regulator
827  * @rdev: regulator name
828  * @supply_rdev: supply regulator name
829  *
830  * Called by platform initialisation code to set the supply regulator for this
831  * regulator. This ensures that a regulators supply will also be enabled by the
832  * core if it's child is enabled.
833  */
834 static int set_supply(struct regulator_dev *rdev,
835         struct regulator_dev *supply_rdev)
836 {
837         int err;
838
839         err = sysfs_create_link(&rdev->dev.kobj, &supply_rdev->dev.kobj,
840                                 "supply");
841         if (err) {
842                 printk(KERN_ERR
843                        "%s: could not add device link %s err %d\n",
844                        __func__, supply_rdev->dev.kobj.name, err);
845                        goto out;
846         }
847         rdev->supply = supply_rdev;
848         list_add(&rdev->slist, &supply_rdev->supply_list);
849 out:
850         return err;
851 }
852
853 /**
854  * set_consumer_device_supply: Bind a regulator to a symbolic supply
855  * @rdev:         regulator source
856  * @consumer_dev: device the supply applies to
857  * @supply:       symbolic name for supply
858  *
859  * Allows platform initialisation code to map physical regulator
860  * sources to symbolic names for supplies for use by devices.  Devices
861  * should use these symbolic names to request regulators, avoiding the
862  * need to provide board-specific regulator names as platform data.
863  */
864 static int set_consumer_device_supply(struct regulator_dev *rdev,
865         struct device *consumer_dev, const char *supply)
866 {
867         struct regulator_map *node;
868
869         if (supply == NULL)
870                 return -EINVAL;
871
872         list_for_each_entry(node, &regulator_map_list, list) {
873                 if (consumer_dev != node->dev)
874                         continue;
875                 if (strcmp(node->supply, supply) != 0)
876                         continue;
877
878                 dev_dbg(consumer_dev, "%s/%s is '%s' supply; fail %s/%s\n",
879                                 dev_name(&node->regulator->dev),
880                                 node->regulator->desc->name,
881                                 supply,
882                                 dev_name(&rdev->dev), rdev->desc->name);
883                 return -EBUSY;
884         }
885
886         node = kmalloc(sizeof(struct regulator_map), GFP_KERNEL);
887         if (node == NULL)
888                 return -ENOMEM;
889
890         node->regulator = rdev;
891         node->dev = consumer_dev;
892         node->supply = supply;
893
894         list_add(&node->list, &regulator_map_list);
895         return 0;
896 }
897
898 static void unset_consumer_device_supply(struct regulator_dev *rdev,
899         struct device *consumer_dev)
900 {
901         struct regulator_map *node, *n;
902
903         list_for_each_entry_safe(node, n, &regulator_map_list, list) {
904                 if (rdev == node->regulator &&
905                         consumer_dev == node->dev) {
906                         list_del(&node->list);
907                         kfree(node);
908                         return;
909                 }
910         }
911 }
912
913 static void unset_regulator_supplies(struct regulator_dev *rdev)
914 {
915         struct regulator_map *node, *n;
916
917         list_for_each_entry_safe(node, n, &regulator_map_list, list) {
918                 if (rdev == node->regulator) {
919                         list_del(&node->list);
920                         kfree(node);
921                         return;
922                 }
923         }
924 }
925
926 #define REG_STR_SIZE    32
927
928 static struct regulator *create_regulator(struct regulator_dev *rdev,
929                                           struct device *dev,
930                                           const char *supply_name)
931 {
932         struct regulator *regulator;
933         char buf[REG_STR_SIZE];
934         int err, size;
935
936         regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
937         if (regulator == NULL)
938                 return NULL;
939
940         mutex_lock(&rdev->mutex);
941         regulator->rdev = rdev;
942         list_add(&regulator->list, &rdev->consumer_list);
943
944         if (dev) {
945                 /* create a 'requested_microamps_name' sysfs entry */
946                 size = scnprintf(buf, REG_STR_SIZE, "microamps_requested_%s",
947                         supply_name);
948                 if (size >= REG_STR_SIZE)
949                         goto overflow_err;
950
951                 regulator->dev = dev;
952                 regulator->dev_attr.attr.name = kstrdup(buf, GFP_KERNEL);
953                 if (regulator->dev_attr.attr.name == NULL)
954                         goto attr_name_err;
955
956                 regulator->dev_attr.attr.owner = THIS_MODULE;
957                 regulator->dev_attr.attr.mode = 0444;
958                 regulator->dev_attr.show = device_requested_uA_show;
959                 err = device_create_file(dev, &regulator->dev_attr);
960                 if (err < 0) {
961                         printk(KERN_WARNING "%s: could not add regulator_dev"
962                                 " load sysfs\n", __func__);
963                         goto attr_name_err;
964                 }
965
966                 /* also add a link to the device sysfs entry */
967                 size = scnprintf(buf, REG_STR_SIZE, "%s-%s",
968                                  dev->kobj.name, supply_name);
969                 if (size >= REG_STR_SIZE)
970                         goto attr_err;
971
972                 regulator->supply_name = kstrdup(buf, GFP_KERNEL);
973                 if (regulator->supply_name == NULL)
974                         goto attr_err;
975
976                 err = sysfs_create_link(&rdev->dev.kobj, &dev->kobj,
977                                         buf);
978                 if (err) {
979                         printk(KERN_WARNING
980                                "%s: could not add device link %s err %d\n",
981                                __func__, dev->kobj.name, err);
982                         device_remove_file(dev, &regulator->dev_attr);
983                         goto link_name_err;
984                 }
985         }
986         mutex_unlock(&rdev->mutex);
987         return regulator;
988 link_name_err:
989         kfree(regulator->supply_name);
990 attr_err:
991         device_remove_file(regulator->dev, &regulator->dev_attr);
992 attr_name_err:
993         kfree(regulator->dev_attr.attr.name);
994 overflow_err:
995         list_del(&regulator->list);
996         kfree(regulator);
997         mutex_unlock(&rdev->mutex);
998         return NULL;
999 }
1000
1001 /**
1002  * regulator_get - lookup and obtain a reference to a regulator.
1003  * @dev: device for regulator "consumer"
1004  * @id: Supply name or regulator ID.
1005  *
1006  * Returns a struct regulator corresponding to the regulator producer,
1007  * or IS_ERR() condition containing errno.
1008  *
1009  * Use of supply names configured via regulator_set_device_supply() is
1010  * strongly encouraged.  It is recommended that the supply name used
1011  * should match the name used for the supply and/or the relevant
1012  * device pins in the datasheet.
1013  */
1014 struct regulator *regulator_get(struct device *dev, const char *id)
1015 {
1016         struct regulator_dev *rdev;
1017         struct regulator_map *map;
1018         struct regulator *regulator = ERR_PTR(-ENODEV);
1019
1020         if (id == NULL) {
1021                 printk(KERN_ERR "regulator: get() with no identifier\n");
1022                 return regulator;
1023         }
1024
1025         mutex_lock(&regulator_list_mutex);
1026
1027         list_for_each_entry(map, &regulator_map_list, list) {
1028                 if (dev == map->dev &&
1029                     strcmp(map->supply, id) == 0) {
1030                         rdev = map->regulator;
1031                         goto found;
1032                 }
1033         }
1034         mutex_unlock(&regulator_list_mutex);
1035         return regulator;
1036
1037 found:
1038         if (!try_module_get(rdev->owner))
1039                 goto out;
1040
1041         regulator = create_regulator(rdev, dev, id);
1042         if (regulator == NULL) {
1043                 regulator = ERR_PTR(-ENOMEM);
1044                 module_put(rdev->owner);
1045         }
1046
1047 out:
1048         mutex_unlock(&regulator_list_mutex);
1049         return regulator;
1050 }
1051 EXPORT_SYMBOL_GPL(regulator_get);
1052
1053 /**
1054  * regulator_put - "free" the regulator source
1055  * @regulator: regulator source
1056  *
1057  * Note: drivers must ensure that all regulator_enable calls made on this
1058  * regulator source are balanced by regulator_disable calls prior to calling
1059  * this function.
1060  */
1061 void regulator_put(struct regulator *regulator)
1062 {
1063         struct regulator_dev *rdev;
1064
1065         if (regulator == NULL || IS_ERR(regulator))
1066                 return;
1067
1068         mutex_lock(&regulator_list_mutex);
1069         rdev = regulator->rdev;
1070
1071         /* remove any sysfs entries */
1072         if (regulator->dev) {
1073                 sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
1074                 kfree(regulator->supply_name);
1075                 device_remove_file(regulator->dev, &regulator->dev_attr);
1076                 kfree(regulator->dev_attr.attr.name);
1077         }
1078         list_del(&regulator->list);
1079         kfree(regulator);
1080
1081         module_put(rdev->owner);
1082         mutex_unlock(&regulator_list_mutex);
1083 }
1084 EXPORT_SYMBOL_GPL(regulator_put);
1085
1086 /* locks held by regulator_enable() */
1087 static int _regulator_enable(struct regulator_dev *rdev)
1088 {
1089         int ret = -EINVAL;
1090
1091         if (!rdev->constraints) {
1092                 printk(KERN_ERR "%s: %s has no constraints\n",
1093                        __func__, rdev->desc->name);
1094                 return ret;
1095         }
1096
1097         /* do we need to enable the supply regulator first */
1098         if (rdev->supply) {
1099                 ret = _regulator_enable(rdev->supply);
1100                 if (ret < 0) {
1101                         printk(KERN_ERR "%s: failed to enable %s: %d\n",
1102                                __func__, rdev->desc->name, ret);
1103                         return ret;
1104                 }
1105         }
1106
1107         /* check voltage and requested load before enabling */
1108         if (rdev->desc->ops->enable) {
1109
1110                 if (rdev->constraints &&
1111                         (rdev->constraints->valid_ops_mask &
1112                         REGULATOR_CHANGE_DRMS))
1113                         drms_uA_update(rdev);
1114
1115                 ret = rdev->desc->ops->enable(rdev);
1116                 if (ret < 0) {
1117                         printk(KERN_ERR "%s: failed to enable %s: %d\n",
1118                                __func__, rdev->desc->name, ret);
1119                         return ret;
1120                 }
1121                 rdev->use_count++;
1122                 return ret;
1123         }
1124
1125         return ret;
1126 }
1127
1128 /**
1129  * regulator_enable - enable regulator output
1130  * @regulator: regulator source
1131  *
1132  * Request that the regulator be enabled with the regulator output at
1133  * the predefined voltage or current value.  Calls to regulator_enable()
1134  * must be balanced with calls to regulator_disable().
1135  *
1136  * NOTE: the output value can be set by other drivers, boot loader or may be
1137  * hardwired in the regulator.
1138  */
1139 int regulator_enable(struct regulator *regulator)
1140 {
1141         struct regulator_dev *rdev = regulator->rdev;
1142         int ret = 0;
1143
1144         mutex_lock(&rdev->mutex);
1145         ret = _regulator_enable(rdev);
1146         mutex_unlock(&rdev->mutex);
1147         return ret;
1148 }
1149 EXPORT_SYMBOL_GPL(regulator_enable);
1150
1151 /* locks held by regulator_disable() */
1152 static int _regulator_disable(struct regulator_dev *rdev)
1153 {
1154         int ret = 0;
1155
1156         if (WARN(rdev->use_count <= 0,
1157                         "unbalanced disables for %s\n",
1158                         rdev->desc->name))
1159                 return -EIO;
1160
1161         /* are we the last user and permitted to disable ? */
1162         if (rdev->use_count == 1 && !rdev->constraints->always_on) {
1163
1164                 /* we are last user */
1165                 if (rdev->desc->ops->disable) {
1166                         ret = rdev->desc->ops->disable(rdev);
1167                         if (ret < 0) {
1168                                 printk(KERN_ERR "%s: failed to disable %s\n",
1169                                        __func__, rdev->desc->name);
1170                                 return ret;
1171                         }
1172                 }
1173
1174                 /* decrease our supplies ref count and disable if required */
1175                 if (rdev->supply)
1176                         _regulator_disable(rdev->supply);
1177
1178                 rdev->use_count = 0;
1179         } else if (rdev->use_count > 1) {
1180
1181                 if (rdev->constraints &&
1182                         (rdev->constraints->valid_ops_mask &
1183                         REGULATOR_CHANGE_DRMS))
1184                         drms_uA_update(rdev);
1185
1186                 rdev->use_count--;
1187         }
1188         return ret;
1189 }
1190
1191 /**
1192  * regulator_disable - disable regulator output
1193  * @regulator: regulator source
1194  *
1195  * Disable the regulator output voltage or current.  Calls to
1196  * regulator_enable() must be balanced with calls to
1197  * regulator_disable().
1198  *
1199  * NOTE: this will only disable the regulator output if no other consumer
1200  * devices have it enabled, the regulator device supports disabling and
1201  * machine constraints permit this operation.
1202  */
1203 int regulator_disable(struct regulator *regulator)
1204 {
1205         struct regulator_dev *rdev = regulator->rdev;
1206         int ret = 0;
1207
1208         mutex_lock(&rdev->mutex);
1209         ret = _regulator_disable(rdev);
1210         mutex_unlock(&rdev->mutex);
1211         return ret;
1212 }
1213 EXPORT_SYMBOL_GPL(regulator_disable);
1214
1215 /* locks held by regulator_force_disable() */
1216 static int _regulator_force_disable(struct regulator_dev *rdev)
1217 {
1218         int ret = 0;
1219
1220         /* force disable */
1221         if (rdev->desc->ops->disable) {
1222                 /* ah well, who wants to live forever... */
1223                 ret = rdev->desc->ops->disable(rdev);
1224                 if (ret < 0) {
1225                         printk(KERN_ERR "%s: failed to force disable %s\n",
1226                                __func__, rdev->desc->name);
1227                         return ret;
1228                 }
1229                 /* notify other consumers that power has been forced off */
1230                 _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE,
1231                         NULL);
1232         }
1233
1234         /* decrease our supplies ref count and disable if required */
1235         if (rdev->supply)
1236                 _regulator_disable(rdev->supply);
1237
1238         rdev->use_count = 0;
1239         return ret;
1240 }
1241
1242 /**
1243  * regulator_force_disable - force disable regulator output
1244  * @regulator: regulator source
1245  *
1246  * Forcibly disable the regulator output voltage or current.
1247  * NOTE: this *will* disable the regulator output even if other consumer
1248  * devices have it enabled. This should be used for situations when device
1249  * damage will likely occur if the regulator is not disabled (e.g. over temp).
1250  */
1251 int regulator_force_disable(struct regulator *regulator)
1252 {
1253         int ret;
1254
1255         mutex_lock(&regulator->rdev->mutex);
1256         regulator->uA_load = 0;
1257         ret = _regulator_force_disable(regulator->rdev);
1258         mutex_unlock(&regulator->rdev->mutex);
1259         return ret;
1260 }
1261 EXPORT_SYMBOL_GPL(regulator_force_disable);
1262
1263 static int _regulator_is_enabled(struct regulator_dev *rdev)
1264 {
1265         int ret;
1266
1267         mutex_lock(&rdev->mutex);
1268
1269         /* sanity check */
1270         if (!rdev->desc->ops->is_enabled) {
1271                 ret = -EINVAL;
1272                 goto out;
1273         }
1274
1275         ret = rdev->desc->ops->is_enabled(rdev);
1276 out:
1277         mutex_unlock(&rdev->mutex);
1278         return ret;
1279 }
1280
1281 /**
1282  * regulator_is_enabled - is the regulator output enabled
1283  * @regulator: regulator source
1284  *
1285  * Returns positive if the regulator driver backing the source/client
1286  * has requested that the device be enabled, zero if it hasn't, else a
1287  * negative errno code.
1288  *
1289  * Note that the device backing this regulator handle can have multiple
1290  * users, so it might be enabled even if regulator_enable() was never
1291  * called for this particular source.
1292  */
1293 int regulator_is_enabled(struct regulator *regulator)
1294 {
1295         return _regulator_is_enabled(regulator->rdev);
1296 }
1297 EXPORT_SYMBOL_GPL(regulator_is_enabled);
1298
1299 /**
1300  * regulator_count_voltages - count regulator_list_voltage() selectors
1301  * @regulator: regulator source
1302  *
1303  * Returns number of selectors, or negative errno.  Selectors are
1304  * numbered starting at zero, and typically correspond to bitfields
1305  * in hardware registers.
1306  */
1307 int regulator_count_voltages(struct regulator *regulator)
1308 {
1309         struct regulator_dev    *rdev = regulator->rdev;
1310
1311         return rdev->desc->n_voltages ? : -EINVAL;
1312 }
1313 EXPORT_SYMBOL_GPL(regulator_count_voltages);
1314
1315 /**
1316  * regulator_list_voltage - enumerate supported voltages
1317  * @regulator: regulator source
1318  * @selector: identify voltage to list
1319  * Context: can sleep
1320  *
1321  * Returns a voltage that can be passed to @regulator_set_voltage(),
1322  * zero if this selector code can't be used on this sytem, or a
1323  * negative errno.
1324  */
1325 int regulator_list_voltage(struct regulator *regulator, unsigned selector)
1326 {
1327         struct regulator_dev    *rdev = regulator->rdev;
1328         struct regulator_ops    *ops = rdev->desc->ops;
1329         int                     ret;
1330
1331         if (!ops->list_voltage || selector >= rdev->desc->n_voltages)
1332                 return -EINVAL;
1333
1334         mutex_lock(&rdev->mutex);
1335         ret = ops->list_voltage(rdev, selector);
1336         mutex_unlock(&rdev->mutex);
1337
1338         if (ret > 0) {
1339                 if (ret < rdev->constraints->min_uV)
1340                         ret = 0;
1341                 else if (ret > rdev->constraints->max_uV)
1342                         ret = 0;
1343         }
1344
1345         return ret;
1346 }
1347 EXPORT_SYMBOL_GPL(regulator_list_voltage);
1348
1349 /**
1350  * regulator_set_voltage - set regulator output voltage
1351  * @regulator: regulator source
1352  * @min_uV: Minimum required voltage in uV
1353  * @max_uV: Maximum acceptable voltage in uV
1354  *
1355  * Sets a voltage regulator to the desired output voltage. This can be set
1356  * during any regulator state. IOW, regulator can be disabled or enabled.
1357  *
1358  * If the regulator is enabled then the voltage will change to the new value
1359  * immediately otherwise if the regulator is disabled the regulator will
1360  * output at the new voltage when enabled.
1361  *
1362  * NOTE: If the regulator is shared between several devices then the lowest
1363  * request voltage that meets the system constraints will be used.
1364  * Regulator system constraints must be set for this regulator before
1365  * calling this function otherwise this call will fail.
1366  */
1367 int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
1368 {
1369         struct regulator_dev *rdev = regulator->rdev;
1370         int ret;
1371
1372         mutex_lock(&rdev->mutex);
1373
1374         /* sanity check */
1375         if (!rdev->desc->ops->set_voltage) {
1376                 ret = -EINVAL;
1377                 goto out;
1378         }
1379
1380         /* constraints check */
1381         ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
1382         if (ret < 0)
1383                 goto out;
1384         regulator->min_uV = min_uV;
1385         regulator->max_uV = max_uV;
1386         ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV);
1387
1388 out:
1389         _notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE, NULL);
1390         mutex_unlock(&rdev->mutex);
1391         return ret;
1392 }
1393 EXPORT_SYMBOL_GPL(regulator_set_voltage);
1394
1395 static int _regulator_get_voltage(struct regulator_dev *rdev)
1396 {
1397         /* sanity check */
1398         if (rdev->desc->ops->get_voltage)
1399                 return rdev->desc->ops->get_voltage(rdev);
1400         else
1401                 return -EINVAL;
1402 }
1403
1404 /**
1405  * regulator_get_voltage - get regulator output voltage
1406  * @regulator: regulator source
1407  *
1408  * This returns the current regulator voltage in uV.
1409  *
1410  * NOTE: If the regulator is disabled it will return the voltage value. This
1411  * function should not be used to determine regulator state.
1412  */
1413 int regulator_get_voltage(struct regulator *regulator)
1414 {
1415         int ret;
1416
1417         mutex_lock(&regulator->rdev->mutex);
1418
1419         ret = _regulator_get_voltage(regulator->rdev);
1420
1421         mutex_unlock(&regulator->rdev->mutex);
1422
1423         return ret;
1424 }
1425 EXPORT_SYMBOL_GPL(regulator_get_voltage);
1426
1427 /**
1428  * regulator_set_current_limit - set regulator output current limit
1429  * @regulator: regulator source
1430  * @min_uA: Minimuum supported current in uA
1431  * @max_uA: Maximum supported current in uA
1432  *
1433  * Sets current sink to the desired output current. This can be set during
1434  * any regulator state. IOW, regulator can be disabled or enabled.
1435  *
1436  * If the regulator is enabled then the current will change to the new value
1437  * immediately otherwise if the regulator is disabled the regulator will
1438  * output at the new current when enabled.
1439  *
1440  * NOTE: Regulator system constraints must be set for this regulator before
1441  * calling this function otherwise this call will fail.
1442  */
1443 int regulator_set_current_limit(struct regulator *regulator,
1444                                int min_uA, int max_uA)
1445 {
1446         struct regulator_dev *rdev = regulator->rdev;
1447         int ret;
1448
1449         mutex_lock(&rdev->mutex);
1450
1451         /* sanity check */
1452         if (!rdev->desc->ops->set_current_limit) {
1453                 ret = -EINVAL;
1454                 goto out;
1455         }
1456
1457         /* constraints check */
1458         ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
1459         if (ret < 0)
1460                 goto out;
1461
1462         ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
1463 out:
1464         mutex_unlock(&rdev->mutex);
1465         return ret;
1466 }
1467 EXPORT_SYMBOL_GPL(regulator_set_current_limit);
1468
1469 static int _regulator_get_current_limit(struct regulator_dev *rdev)
1470 {
1471         int ret;
1472
1473         mutex_lock(&rdev->mutex);
1474
1475         /* sanity check */
1476         if (!rdev->desc->ops->get_current_limit) {
1477                 ret = -EINVAL;
1478                 goto out;
1479         }
1480
1481         ret = rdev->desc->ops->get_current_limit(rdev);
1482 out:
1483         mutex_unlock(&rdev->mutex);
1484         return ret;
1485 }
1486
1487 /**
1488  * regulator_get_current_limit - get regulator output current
1489  * @regulator: regulator source
1490  *
1491  * This returns the current supplied by the specified current sink in uA.
1492  *
1493  * NOTE: If the regulator is disabled it will return the current value. This
1494  * function should not be used to determine regulator state.
1495  */
1496 int regulator_get_current_limit(struct regulator *regulator)
1497 {
1498         return _regulator_get_current_limit(regulator->rdev);
1499 }
1500 EXPORT_SYMBOL_GPL(regulator_get_current_limit);
1501
1502 /**
1503  * regulator_set_mode - set regulator operating mode
1504  * @regulator: regulator source
1505  * @mode: operating mode - one of the REGULATOR_MODE constants
1506  *
1507  * Set regulator operating mode to increase regulator efficiency or improve
1508  * regulation performance.
1509  *
1510  * NOTE: Regulator system constraints must be set for this regulator before
1511  * calling this function otherwise this call will fail.
1512  */
1513 int regulator_set_mode(struct regulator *regulator, unsigned int mode)
1514 {
1515         struct regulator_dev *rdev = regulator->rdev;
1516         int ret;
1517
1518         mutex_lock(&rdev->mutex);
1519
1520         /* sanity check */
1521         if (!rdev->desc->ops->set_mode) {
1522                 ret = -EINVAL;
1523                 goto out;
1524         }
1525
1526         /* constraints check */
1527         ret = regulator_check_mode(rdev, mode);
1528         if (ret < 0)
1529                 goto out;
1530
1531         ret = rdev->desc->ops->set_mode(rdev, mode);
1532 out:
1533         mutex_unlock(&rdev->mutex);
1534         return ret;
1535 }
1536 EXPORT_SYMBOL_GPL(regulator_set_mode);
1537
1538 static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
1539 {
1540         int ret;
1541
1542         mutex_lock(&rdev->mutex);
1543
1544         /* sanity check */
1545         if (!rdev->desc->ops->get_mode) {
1546                 ret = -EINVAL;
1547                 goto out;
1548         }
1549
1550         ret = rdev->desc->ops->get_mode(rdev);
1551 out:
1552         mutex_unlock(&rdev->mutex);
1553         return ret;
1554 }
1555
1556 /**
1557  * regulator_get_mode - get regulator operating mode
1558  * @regulator: regulator source
1559  *
1560  * Get the current regulator operating mode.
1561  */
1562 unsigned int regulator_get_mode(struct regulator *regulator)
1563 {
1564         return _regulator_get_mode(regulator->rdev);
1565 }
1566 EXPORT_SYMBOL_GPL(regulator_get_mode);
1567
1568 /**
1569  * regulator_set_optimum_mode - set regulator optimum operating mode
1570  * @regulator: regulator source
1571  * @uA_load: load current
1572  *
1573  * Notifies the regulator core of a new device load. This is then used by
1574  * DRMS (if enabled by constraints) to set the most efficient regulator
1575  * operating mode for the new regulator loading.
1576  *
1577  * Consumer devices notify their supply regulator of the maximum power
1578  * they will require (can be taken from device datasheet in the power
1579  * consumption tables) when they change operational status and hence power
1580  * state. Examples of operational state changes that can affect power
1581  * consumption are :-
1582  *
1583  *    o Device is opened / closed.
1584  *    o Device I/O is about to begin or has just finished.
1585  *    o Device is idling in between work.
1586  *
1587  * This information is also exported via sysfs to userspace.
1588  *
1589  * DRMS will sum the total requested load on the regulator and change
1590  * to the most efficient operating mode if platform constraints allow.
1591  *
1592  * Returns the new regulator mode or error.
1593  */
1594 int regulator_set_optimum_mode(struct regulator *regulator, int uA_load)
1595 {
1596         struct regulator_dev *rdev = regulator->rdev;
1597         struct regulator *consumer;
1598         int ret, output_uV, input_uV, total_uA_load = 0;
1599         unsigned int mode;
1600
1601         mutex_lock(&rdev->mutex);
1602
1603         regulator->uA_load = uA_load;
1604         ret = regulator_check_drms(rdev);
1605         if (ret < 0)
1606                 goto out;
1607         ret = -EINVAL;
1608
1609         /* sanity check */
1610         if (!rdev->desc->ops->get_optimum_mode)
1611                 goto out;
1612
1613         /* get output voltage */
1614         output_uV = rdev->desc->ops->get_voltage(rdev);
1615         if (output_uV <= 0) {
1616                 printk(KERN_ERR "%s: invalid output voltage found for %s\n",
1617                         __func__, rdev->desc->name);
1618                 goto out;
1619         }
1620
1621         /* get input voltage */
1622         if (rdev->supply && rdev->supply->desc->ops->get_voltage)
1623                 input_uV = rdev->supply->desc->ops->get_voltage(rdev->supply);
1624         else
1625                 input_uV = rdev->constraints->input_uV;
1626         if (input_uV <= 0) {
1627                 printk(KERN_ERR "%s: invalid input voltage found for %s\n",
1628                         __func__, rdev->desc->name);
1629                 goto out;
1630         }
1631
1632         /* calc total requested load for this regulator */
1633         list_for_each_entry(consumer, &rdev->consumer_list, list)
1634             total_uA_load += consumer->uA_load;
1635
1636         mode = rdev->desc->ops->get_optimum_mode(rdev,
1637                                                  input_uV, output_uV,
1638                                                  total_uA_load);
1639         ret = regulator_check_mode(rdev, mode);
1640         if (ret < 0) {
1641                 printk(KERN_ERR "%s: failed to get optimum mode for %s @"
1642                         " %d uA %d -> %d uV\n", __func__, rdev->desc->name,
1643                         total_uA_load, input_uV, output_uV);
1644                 goto out;
1645         }
1646
1647         ret = rdev->desc->ops->set_mode(rdev, mode);
1648         if (ret < 0) {
1649                 printk(KERN_ERR "%s: failed to set optimum mode %x for %s\n",
1650                         __func__, mode, rdev->desc->name);
1651                 goto out;
1652         }
1653         ret = mode;
1654 out:
1655         mutex_unlock(&rdev->mutex);
1656         return ret;
1657 }
1658 EXPORT_SYMBOL_GPL(regulator_set_optimum_mode);
1659
1660 /**
1661  * regulator_register_notifier - register regulator event notifier
1662  * @regulator: regulator source
1663  * @nb: notifier block
1664  *
1665  * Register notifier block to receive regulator events.
1666  */
1667 int regulator_register_notifier(struct regulator *regulator,
1668                               struct notifier_block *nb)
1669 {
1670         return blocking_notifier_chain_register(&regulator->rdev->notifier,
1671                                                 nb);
1672 }
1673 EXPORT_SYMBOL_GPL(regulator_register_notifier);
1674
1675 /**
1676  * regulator_unregister_notifier - unregister regulator event notifier
1677  * @regulator: regulator source
1678  * @nb: notifier block
1679  *
1680  * Unregister regulator event notifier block.
1681  */
1682 int regulator_unregister_notifier(struct regulator *regulator,
1683                                 struct notifier_block *nb)
1684 {
1685         return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
1686                                                   nb);
1687 }
1688 EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
1689
1690 /* notify regulator consumers and downstream regulator consumers.
1691  * Note mutex must be held by caller.
1692  */
1693 static void _notifier_call_chain(struct regulator_dev *rdev,
1694                                   unsigned long event, void *data)
1695 {
1696         struct regulator_dev *_rdev;
1697
1698         /* call rdev chain first */
1699         blocking_notifier_call_chain(&rdev->notifier, event, NULL);
1700
1701         /* now notify regulator we supply */
1702         list_for_each_entry(_rdev, &rdev->supply_list, slist) {
1703           mutex_lock(&_rdev->mutex);
1704           _notifier_call_chain(_rdev, event, data);
1705           mutex_unlock(&_rdev->mutex);
1706         }
1707 }
1708
1709 /**
1710  * regulator_bulk_get - get multiple regulator consumers
1711  *
1712  * @dev:           Device to supply
1713  * @num_consumers: Number of consumers to register
1714  * @consumers:     Configuration of consumers; clients are stored here.
1715  *
1716  * @return 0 on success, an errno on failure.
1717  *
1718  * This helper function allows drivers to get several regulator
1719  * consumers in one operation.  If any of the regulators cannot be
1720  * acquired then any regulators that were allocated will be freed
1721  * before returning to the caller.
1722  */
1723 int regulator_bulk_get(struct device *dev, int num_consumers,
1724                        struct regulator_bulk_data *consumers)
1725 {
1726         int i;
1727         int ret;
1728
1729         for (i = 0; i < num_consumers; i++)
1730                 consumers[i].consumer = NULL;
1731
1732         for (i = 0; i < num_consumers; i++) {
1733                 consumers[i].consumer = regulator_get(dev,
1734                                                       consumers[i].supply);
1735                 if (IS_ERR(consumers[i].consumer)) {
1736                         dev_err(dev, "Failed to get supply '%s'\n",
1737                                 consumers[i].supply);
1738                         ret = PTR_ERR(consumers[i].consumer);
1739                         consumers[i].consumer = NULL;
1740                         goto err;
1741                 }
1742         }
1743
1744         return 0;
1745
1746 err:
1747         for (i = 0; i < num_consumers && consumers[i].consumer; i++)
1748                 regulator_put(consumers[i].consumer);
1749
1750         return ret;
1751 }
1752 EXPORT_SYMBOL_GPL(regulator_bulk_get);
1753
1754 /**
1755  * regulator_bulk_enable - enable multiple regulator consumers
1756  *
1757  * @num_consumers: Number of consumers
1758  * @consumers:     Consumer data; clients are stored here.
1759  * @return         0 on success, an errno on failure
1760  *
1761  * This convenience API allows consumers to enable multiple regulator
1762  * clients in a single API call.  If any consumers cannot be enabled
1763  * then any others that were enabled will be disabled again prior to
1764  * return.
1765  */
1766 int regulator_bulk_enable(int num_consumers,
1767                           struct regulator_bulk_data *consumers)
1768 {
1769         int i;
1770         int ret;
1771
1772         for (i = 0; i < num_consumers; i++) {
1773                 ret = regulator_enable(consumers[i].consumer);
1774                 if (ret != 0)
1775                         goto err;
1776         }
1777
1778         return 0;
1779
1780 err:
1781         printk(KERN_ERR "Failed to enable %s\n", consumers[i].supply);
1782         for (i = 0; i < num_consumers; i++)
1783                 regulator_disable(consumers[i].consumer);
1784
1785         return ret;
1786 }
1787 EXPORT_SYMBOL_GPL(regulator_bulk_enable);
1788
1789 /**
1790  * regulator_bulk_disable - disable multiple regulator consumers
1791  *
1792  * @num_consumers: Number of consumers
1793  * @consumers:     Consumer data; clients are stored here.
1794  * @return         0 on success, an errno on failure
1795  *
1796  * This convenience API allows consumers to disable multiple regulator
1797  * clients in a single API call.  If any consumers cannot be enabled
1798  * then any others that were disabled will be disabled again prior to
1799  * return.
1800  */
1801 int regulator_bulk_disable(int num_consumers,
1802                            struct regulator_bulk_data *consumers)
1803 {
1804         int i;
1805         int ret;
1806
1807         for (i = 0; i < num_consumers; i++) {
1808                 ret = regulator_disable(consumers[i].consumer);
1809                 if (ret != 0)
1810                         goto err;
1811         }
1812
1813         return 0;
1814
1815 err:
1816         printk(KERN_ERR "Failed to disable %s\n", consumers[i].supply);
1817         for (i = 0; i < num_consumers; i++)
1818                 regulator_enable(consumers[i].consumer);
1819
1820         return ret;
1821 }
1822 EXPORT_SYMBOL_GPL(regulator_bulk_disable);
1823
1824 /**
1825  * regulator_bulk_free - free multiple regulator consumers
1826  *
1827  * @num_consumers: Number of consumers
1828  * @consumers:     Consumer data; clients are stored here.
1829  *
1830  * This convenience API allows consumers to free multiple regulator
1831  * clients in a single API call.
1832  */
1833 void regulator_bulk_free(int num_consumers,
1834                          struct regulator_bulk_data *consumers)
1835 {
1836         int i;
1837
1838         for (i = 0; i < num_consumers; i++) {
1839                 regulator_put(consumers[i].consumer);
1840                 consumers[i].consumer = NULL;
1841         }
1842 }
1843 EXPORT_SYMBOL_GPL(regulator_bulk_free);
1844
1845 /**
1846  * regulator_notifier_call_chain - call regulator event notifier
1847  * @rdev: regulator source
1848  * @event: notifier block
1849  * @data: callback-specific data.
1850  *
1851  * Called by regulator drivers to notify clients a regulator event has
1852  * occurred. We also notify regulator clients downstream.
1853  * Note lock must be held by caller.
1854  */
1855 int regulator_notifier_call_chain(struct regulator_dev *rdev,
1856                                   unsigned long event, void *data)
1857 {
1858         _notifier_call_chain(rdev, event, data);
1859         return NOTIFY_DONE;
1860
1861 }
1862 EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
1863
1864 /*
1865  * To avoid cluttering sysfs (and memory) with useless state, only
1866  * create attributes that can be meaningfully displayed.
1867  */
1868 static int add_regulator_attributes(struct regulator_dev *rdev)
1869 {
1870         struct device           *dev = &rdev->dev;
1871         struct regulator_ops    *ops = rdev->desc->ops;
1872         int                     status = 0;
1873
1874         /* some attributes need specific methods to be displayed */
1875         if (ops->get_voltage) {
1876                 status = device_create_file(dev, &dev_attr_microvolts);
1877                 if (status < 0)
1878                         return status;
1879         }
1880         if (ops->get_current_limit) {
1881                 status = device_create_file(dev, &dev_attr_microamps);
1882                 if (status < 0)
1883                         return status;
1884         }
1885         if (ops->get_mode) {
1886                 status = device_create_file(dev, &dev_attr_opmode);
1887                 if (status < 0)
1888                         return status;
1889         }
1890         if (ops->is_enabled) {
1891                 status = device_create_file(dev, &dev_attr_state);
1892                 if (status < 0)
1893                         return status;
1894         }
1895         if (ops->get_status) {
1896                 status = device_create_file(dev, &dev_attr_status);
1897                 if (status < 0)
1898                         return status;
1899         }
1900
1901         /* some attributes are type-specific */
1902         if (rdev->desc->type == REGULATOR_CURRENT) {
1903                 status = device_create_file(dev, &dev_attr_requested_microamps);
1904                 if (status < 0)
1905                         return status;
1906         }
1907
1908         /* all the other attributes exist to support constraints;
1909          * don't show them if there are no constraints, or if the
1910          * relevant supporting methods are missing.
1911          */
1912         if (!rdev->constraints)
1913                 return status;
1914
1915         /* constraints need specific supporting methods */
1916         if (ops->set_voltage) {
1917                 status = device_create_file(dev, &dev_attr_min_microvolts);
1918                 if (status < 0)
1919                         return status;
1920                 status = device_create_file(dev, &dev_attr_max_microvolts);
1921                 if (status < 0)
1922                         return status;
1923         }
1924         if (ops->set_current_limit) {
1925                 status = device_create_file(dev, &dev_attr_min_microamps);
1926                 if (status < 0)
1927                         return status;
1928                 status = device_create_file(dev, &dev_attr_max_microamps);
1929                 if (status < 0)
1930                         return status;
1931         }
1932
1933         /* suspend mode constraints need multiple supporting methods */
1934         if (!(ops->set_suspend_enable && ops->set_suspend_disable))
1935                 return status;
1936
1937         status = device_create_file(dev, &dev_attr_suspend_standby_state);
1938         if (status < 0)
1939                 return status;
1940         status = device_create_file(dev, &dev_attr_suspend_mem_state);
1941         if (status < 0)
1942                 return status;
1943         status = device_create_file(dev, &dev_attr_suspend_disk_state);
1944         if (status < 0)
1945                 return status;
1946
1947         if (ops->set_suspend_voltage) {
1948                 status = device_create_file(dev,
1949                                 &dev_attr_suspend_standby_microvolts);
1950                 if (status < 0)
1951                         return status;
1952                 status = device_create_file(dev,
1953                                 &dev_attr_suspend_mem_microvolts);
1954                 if (status < 0)
1955                         return status;
1956                 status = device_create_file(dev,
1957                                 &dev_attr_suspend_disk_microvolts);
1958                 if (status < 0)
1959                         return status;
1960         }
1961
1962         if (ops->set_suspend_mode) {
1963                 status = device_create_file(dev,
1964                                 &dev_attr_suspend_standby_mode);
1965                 if (status < 0)
1966                         return status;
1967                 status = device_create_file(dev,
1968                                 &dev_attr_suspend_mem_mode);
1969                 if (status < 0)
1970                         return status;
1971                 status = device_create_file(dev,
1972                                 &dev_attr_suspend_disk_mode);
1973                 if (status < 0)
1974                         return status;
1975         }
1976
1977         return status;
1978 }
1979
1980 /**
1981  * regulator_register - register regulator
1982  * @regulator_desc: regulator to register
1983  * @dev: struct device for the regulator
1984  * @init_data: platform provided init data, passed through by driver
1985  * @driver_data: private regulator data
1986  *
1987  * Called by regulator drivers to register a regulator.
1988  * Returns 0 on success.
1989  */
1990 struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc,
1991         struct device *dev, struct regulator_init_data *init_data,
1992         void *driver_data)
1993 {
1994         static atomic_t regulator_no = ATOMIC_INIT(0);
1995         struct regulator_dev *rdev;
1996         int ret, i;
1997
1998         if (regulator_desc == NULL)
1999                 return ERR_PTR(-EINVAL);
2000
2001         if (regulator_desc->name == NULL || regulator_desc->ops == NULL)
2002                 return ERR_PTR(-EINVAL);
2003
2004         if (!regulator_desc->type == REGULATOR_VOLTAGE &&
2005             !regulator_desc->type == REGULATOR_CURRENT)
2006                 return ERR_PTR(-EINVAL);
2007
2008         if (!init_data)
2009                 return ERR_PTR(-EINVAL);
2010
2011         rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
2012         if (rdev == NULL)
2013                 return ERR_PTR(-ENOMEM);
2014
2015         mutex_lock(&regulator_list_mutex);
2016
2017         mutex_init(&rdev->mutex);
2018         rdev->reg_data = driver_data;
2019         rdev->owner = regulator_desc->owner;
2020         rdev->desc = regulator_desc;
2021         INIT_LIST_HEAD(&rdev->consumer_list);
2022         INIT_LIST_HEAD(&rdev->supply_list);
2023         INIT_LIST_HEAD(&rdev->list);
2024         INIT_LIST_HEAD(&rdev->slist);
2025         BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
2026
2027         /* preform any regulator specific init */
2028         if (init_data->regulator_init) {
2029                 ret = init_data->regulator_init(rdev->reg_data);
2030                 if (ret < 0)
2031                         goto clean;
2032         }
2033
2034         /* register with sysfs */
2035         rdev->dev.class = &regulator_class;
2036         rdev->dev.parent = dev;
2037         dev_set_name(&rdev->dev, "regulator.%d",
2038                      atomic_inc_return(&regulator_no) - 1);
2039         ret = device_register(&rdev->dev);
2040         if (ret != 0)
2041                 goto clean;
2042
2043         dev_set_drvdata(&rdev->dev, rdev);
2044
2045         /* set regulator constraints */
2046         ret = set_machine_constraints(rdev, &init_data->constraints);
2047         if (ret < 0)
2048                 goto scrub;
2049
2050         /* add attributes supported by this regulator */
2051         ret = add_regulator_attributes(rdev);
2052         if (ret < 0)
2053                 goto scrub;
2054
2055         /* set supply regulator if it exists */
2056         if (init_data->supply_regulator_dev) {
2057                 ret = set_supply(rdev,
2058                         dev_get_drvdata(init_data->supply_regulator_dev));
2059                 if (ret < 0)
2060                         goto scrub;
2061         }
2062
2063         /* add consumers devices */
2064         for (i = 0; i < init_data->num_consumer_supplies; i++) {
2065                 ret = set_consumer_device_supply(rdev,
2066                         init_data->consumer_supplies[i].dev,
2067                         init_data->consumer_supplies[i].supply);
2068                 if (ret < 0) {
2069                         for (--i; i >= 0; i--)
2070                                 unset_consumer_device_supply(rdev,
2071                                         init_data->consumer_supplies[i].dev);
2072                         goto scrub;
2073                 }
2074         }
2075
2076         list_add(&rdev->list, &regulator_list);
2077 out:
2078         mutex_unlock(&regulator_list_mutex);
2079         return rdev;
2080
2081 scrub:
2082         device_unregister(&rdev->dev);
2083 clean:
2084         kfree(rdev);
2085         rdev = ERR_PTR(ret);
2086         goto out;
2087 }
2088 EXPORT_SYMBOL_GPL(regulator_register);
2089
2090 /**
2091  * regulator_unregister - unregister regulator
2092  * @rdev: regulator to unregister
2093  *
2094  * Called by regulator drivers to unregister a regulator.
2095  */
2096 void regulator_unregister(struct regulator_dev *rdev)
2097 {
2098         if (rdev == NULL)
2099                 return;
2100
2101         mutex_lock(&regulator_list_mutex);
2102         unset_regulator_supplies(rdev);
2103         list_del(&rdev->list);
2104         if (rdev->supply)
2105                 sysfs_remove_link(&rdev->dev.kobj, "supply");
2106         device_unregister(&rdev->dev);
2107         mutex_unlock(&regulator_list_mutex);
2108 }
2109 EXPORT_SYMBOL_GPL(regulator_unregister);
2110
2111 /**
2112  * regulator_suspend_prepare - prepare regulators for system wide suspend
2113  * @state: system suspend state
2114  *
2115  * Configure each regulator with it's suspend operating parameters for state.
2116  * This will usually be called by machine suspend code prior to supending.
2117  */
2118 int regulator_suspend_prepare(suspend_state_t state)
2119 {
2120         struct regulator_dev *rdev;
2121         int ret = 0;
2122
2123         /* ON is handled by regulator active state */
2124         if (state == PM_SUSPEND_ON)
2125                 return -EINVAL;
2126
2127         mutex_lock(&regulator_list_mutex);
2128         list_for_each_entry(rdev, &regulator_list, list) {
2129
2130                 mutex_lock(&rdev->mutex);
2131                 ret = suspend_prepare(rdev, state);
2132                 mutex_unlock(&rdev->mutex);
2133
2134                 if (ret < 0) {
2135                         printk(KERN_ERR "%s: failed to prepare %s\n",
2136                                 __func__, rdev->desc->name);
2137                         goto out;
2138                 }
2139         }
2140 out:
2141         mutex_unlock(&regulator_list_mutex);
2142         return ret;
2143 }
2144 EXPORT_SYMBOL_GPL(regulator_suspend_prepare);
2145
2146 /**
2147  * regulator_has_full_constraints - the system has fully specified constraints
2148  *
2149  * Calling this function will cause the regulator API to disable all
2150  * regulators which have a zero use count and don't have an always_on
2151  * constraint in a late_initcall.
2152  *
2153  * The intention is that this will become the default behaviour in a
2154  * future kernel release so users are encouraged to use this facility
2155  * now.
2156  */
2157 void regulator_has_full_constraints(void)
2158 {
2159         has_full_constraints = 1;
2160 }
2161 EXPORT_SYMBOL_GPL(regulator_has_full_constraints);
2162
2163 /**
2164  * rdev_get_drvdata - get rdev regulator driver data
2165  * @rdev: regulator
2166  *
2167  * Get rdev regulator driver private data. This call can be used in the
2168  * regulator driver context.
2169  */
2170 void *rdev_get_drvdata(struct regulator_dev *rdev)
2171 {
2172         return rdev->reg_data;
2173 }
2174 EXPORT_SYMBOL_GPL(rdev_get_drvdata);
2175
2176 /**
2177  * regulator_get_drvdata - get regulator driver data
2178  * @regulator: regulator
2179  *
2180  * Get regulator driver private data. This call can be used in the consumer
2181  * driver context when non API regulator specific functions need to be called.
2182  */
2183 void *regulator_get_drvdata(struct regulator *regulator)
2184 {
2185         return regulator->rdev->reg_data;
2186 }
2187 EXPORT_SYMBOL_GPL(regulator_get_drvdata);
2188
2189 /**
2190  * regulator_set_drvdata - set regulator driver data
2191  * @regulator: regulator
2192  * @data: data
2193  */
2194 void regulator_set_drvdata(struct regulator *regulator, void *data)
2195 {
2196         regulator->rdev->reg_data = data;
2197 }
2198 EXPORT_SYMBOL_GPL(regulator_set_drvdata);
2199
2200 /**
2201  * regulator_get_id - get regulator ID
2202  * @rdev: regulator
2203  */
2204 int rdev_get_id(struct regulator_dev *rdev)
2205 {
2206         return rdev->desc->id;
2207 }
2208 EXPORT_SYMBOL_GPL(rdev_get_id);
2209
2210 struct device *rdev_get_dev(struct regulator_dev *rdev)
2211 {
2212         return &rdev->dev;
2213 }
2214 EXPORT_SYMBOL_GPL(rdev_get_dev);
2215
2216 void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
2217 {
2218         return reg_init_data->driver_data;
2219 }
2220 EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
2221
2222 static int __init regulator_init(void)
2223 {
2224         printk(KERN_INFO "regulator: core version %s\n", REGULATOR_VERSION);
2225         return class_register(&regulator_class);
2226 }
2227
2228 /* init early to allow our consumers to complete system booting */
2229 core_initcall(regulator_init);
2230
2231 static int __init regulator_init_complete(void)
2232 {
2233         struct regulator_dev *rdev;
2234         struct regulator_ops *ops;
2235         struct regulation_constraints *c;
2236         int enabled, ret;
2237         const char *name;
2238
2239         mutex_lock(&regulator_list_mutex);
2240
2241         /* If we have a full configuration then disable any regulators
2242          * which are not in use or always_on.  This will become the
2243          * default behaviour in the future.
2244          */
2245         list_for_each_entry(rdev, &regulator_list, list) {
2246                 ops = rdev->desc->ops;
2247                 c = rdev->constraints;
2248
2249                 if (c->name)
2250                         name = c->name;
2251                 else if (rdev->desc->name)
2252                         name = rdev->desc->name;
2253                 else
2254                         name = "regulator";
2255
2256                 if (!ops->disable || c->always_on)
2257                         continue;
2258
2259                 mutex_lock(&rdev->mutex);
2260
2261                 if (rdev->use_count)
2262                         goto unlock;
2263
2264                 /* If we can't read the status assume it's on. */
2265                 if (ops->is_enabled)
2266                         enabled = ops->is_enabled(rdev);
2267                 else
2268                         enabled = 1;
2269
2270                 if (!enabled)
2271                         goto unlock;
2272
2273                 if (has_full_constraints) {
2274                         /* We log since this may kill the system if it
2275                          * goes wrong. */
2276                         printk(KERN_INFO "%s: disabling %s\n",
2277                                __func__, name);
2278                         ret = ops->disable(rdev);
2279                         if (ret != 0) {
2280                                 printk(KERN_ERR
2281                                        "%s: couldn't disable %s: %d\n",
2282                                        __func__, name, ret);
2283                         }
2284                 } else {
2285                         /* The intention is that in future we will
2286                          * assume that full constraints are provided
2287                          * so warn even if we aren't going to do
2288                          * anything here.
2289                          */
2290                         printk(KERN_WARNING
2291                                "%s: incomplete constraints, leaving %s on\n",
2292                                __func__, name);
2293                 }
2294
2295 unlock:
2296                 mutex_unlock(&rdev->mutex);
2297         }
2298
2299         mutex_unlock(&regulator_list_mutex);
2300
2301         return 0;
2302 }
2303 late_initcall(regulator_init_complete);