Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/kaber/nf-next-2.6
[linux-2.6.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         const char *dev_name;   /* The dev_name() for the consumer */
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 && 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         ssize_t ret;
284
285         mutex_lock(&rdev->mutex);
286         ret = regulator_print_state(buf, _regulator_is_enabled(rdev));
287         mutex_unlock(&rdev->mutex);
288
289         return ret;
290 }
291 static DEVICE_ATTR(state, 0444, regulator_state_show, NULL);
292
293 static ssize_t regulator_status_show(struct device *dev,
294                                    struct device_attribute *attr, char *buf)
295 {
296         struct regulator_dev *rdev = dev_get_drvdata(dev);
297         int status;
298         char *label;
299
300         status = rdev->desc->ops->get_status(rdev);
301         if (status < 0)
302                 return status;
303
304         switch (status) {
305         case REGULATOR_STATUS_OFF:
306                 label = "off";
307                 break;
308         case REGULATOR_STATUS_ON:
309                 label = "on";
310                 break;
311         case REGULATOR_STATUS_ERROR:
312                 label = "error";
313                 break;
314         case REGULATOR_STATUS_FAST:
315                 label = "fast";
316                 break;
317         case REGULATOR_STATUS_NORMAL:
318                 label = "normal";
319                 break;
320         case REGULATOR_STATUS_IDLE:
321                 label = "idle";
322                 break;
323         case REGULATOR_STATUS_STANDBY:
324                 label = "standby";
325                 break;
326         default:
327                 return -ERANGE;
328         }
329
330         return sprintf(buf, "%s\n", label);
331 }
332 static DEVICE_ATTR(status, 0444, regulator_status_show, NULL);
333
334 static ssize_t regulator_min_uA_show(struct device *dev,
335                                     struct device_attribute *attr, char *buf)
336 {
337         struct regulator_dev *rdev = dev_get_drvdata(dev);
338
339         if (!rdev->constraints)
340                 return sprintf(buf, "constraint not defined\n");
341
342         return sprintf(buf, "%d\n", rdev->constraints->min_uA);
343 }
344 static DEVICE_ATTR(min_microamps, 0444, regulator_min_uA_show, NULL);
345
346 static ssize_t regulator_max_uA_show(struct device *dev,
347                                     struct device_attribute *attr, char *buf)
348 {
349         struct regulator_dev *rdev = dev_get_drvdata(dev);
350
351         if (!rdev->constraints)
352                 return sprintf(buf, "constraint not defined\n");
353
354         return sprintf(buf, "%d\n", rdev->constraints->max_uA);
355 }
356 static DEVICE_ATTR(max_microamps, 0444, regulator_max_uA_show, NULL);
357
358 static ssize_t regulator_min_uV_show(struct device *dev,
359                                     struct device_attribute *attr, char *buf)
360 {
361         struct regulator_dev *rdev = dev_get_drvdata(dev);
362
363         if (!rdev->constraints)
364                 return sprintf(buf, "constraint not defined\n");
365
366         return sprintf(buf, "%d\n", rdev->constraints->min_uV);
367 }
368 static DEVICE_ATTR(min_microvolts, 0444, regulator_min_uV_show, NULL);
369
370 static ssize_t regulator_max_uV_show(struct device *dev,
371                                     struct device_attribute *attr, char *buf)
372 {
373         struct regulator_dev *rdev = dev_get_drvdata(dev);
374
375         if (!rdev->constraints)
376                 return sprintf(buf, "constraint not defined\n");
377
378         return sprintf(buf, "%d\n", rdev->constraints->max_uV);
379 }
380 static DEVICE_ATTR(max_microvolts, 0444, regulator_max_uV_show, NULL);
381
382 static ssize_t regulator_total_uA_show(struct device *dev,
383                                       struct device_attribute *attr, char *buf)
384 {
385         struct regulator_dev *rdev = dev_get_drvdata(dev);
386         struct regulator *regulator;
387         int uA = 0;
388
389         mutex_lock(&rdev->mutex);
390         list_for_each_entry(regulator, &rdev->consumer_list, list)
391             uA += regulator->uA_load;
392         mutex_unlock(&rdev->mutex);
393         return sprintf(buf, "%d\n", uA);
394 }
395 static DEVICE_ATTR(requested_microamps, 0444, regulator_total_uA_show, NULL);
396
397 static ssize_t regulator_num_users_show(struct device *dev,
398                                       struct device_attribute *attr, char *buf)
399 {
400         struct regulator_dev *rdev = dev_get_drvdata(dev);
401         return sprintf(buf, "%d\n", rdev->use_count);
402 }
403
404 static ssize_t regulator_type_show(struct device *dev,
405                                   struct device_attribute *attr, char *buf)
406 {
407         struct regulator_dev *rdev = dev_get_drvdata(dev);
408
409         switch (rdev->desc->type) {
410         case REGULATOR_VOLTAGE:
411                 return sprintf(buf, "voltage\n");
412         case REGULATOR_CURRENT:
413                 return sprintf(buf, "current\n");
414         }
415         return sprintf(buf, "unknown\n");
416 }
417
418 static ssize_t regulator_suspend_mem_uV_show(struct device *dev,
419                                 struct device_attribute *attr, char *buf)
420 {
421         struct regulator_dev *rdev = dev_get_drvdata(dev);
422
423         return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
424 }
425 static DEVICE_ATTR(suspend_mem_microvolts, 0444,
426                 regulator_suspend_mem_uV_show, NULL);
427
428 static ssize_t regulator_suspend_disk_uV_show(struct device *dev,
429                                 struct device_attribute *attr, char *buf)
430 {
431         struct regulator_dev *rdev = dev_get_drvdata(dev);
432
433         return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
434 }
435 static DEVICE_ATTR(suspend_disk_microvolts, 0444,
436                 regulator_suspend_disk_uV_show, NULL);
437
438 static ssize_t regulator_suspend_standby_uV_show(struct device *dev,
439                                 struct device_attribute *attr, char *buf)
440 {
441         struct regulator_dev *rdev = dev_get_drvdata(dev);
442
443         return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
444 }
445 static DEVICE_ATTR(suspend_standby_microvolts, 0444,
446                 regulator_suspend_standby_uV_show, NULL);
447
448 static ssize_t regulator_suspend_mem_mode_show(struct device *dev,
449                                 struct device_attribute *attr, char *buf)
450 {
451         struct regulator_dev *rdev = dev_get_drvdata(dev);
452
453         return regulator_print_opmode(buf,
454                 rdev->constraints->state_mem.mode);
455 }
456 static DEVICE_ATTR(suspend_mem_mode, 0444,
457                 regulator_suspend_mem_mode_show, NULL);
458
459 static ssize_t regulator_suspend_disk_mode_show(struct device *dev,
460                                 struct device_attribute *attr, char *buf)
461 {
462         struct regulator_dev *rdev = dev_get_drvdata(dev);
463
464         return regulator_print_opmode(buf,
465                 rdev->constraints->state_disk.mode);
466 }
467 static DEVICE_ATTR(suspend_disk_mode, 0444,
468                 regulator_suspend_disk_mode_show, NULL);
469
470 static ssize_t regulator_suspend_standby_mode_show(struct device *dev,
471                                 struct device_attribute *attr, char *buf)
472 {
473         struct regulator_dev *rdev = dev_get_drvdata(dev);
474
475         return regulator_print_opmode(buf,
476                 rdev->constraints->state_standby.mode);
477 }
478 static DEVICE_ATTR(suspend_standby_mode, 0444,
479                 regulator_suspend_standby_mode_show, NULL);
480
481 static ssize_t regulator_suspend_mem_state_show(struct device *dev,
482                                    struct device_attribute *attr, char *buf)
483 {
484         struct regulator_dev *rdev = dev_get_drvdata(dev);
485
486         return regulator_print_state(buf,
487                         rdev->constraints->state_mem.enabled);
488 }
489 static DEVICE_ATTR(suspend_mem_state, 0444,
490                 regulator_suspend_mem_state_show, NULL);
491
492 static ssize_t regulator_suspend_disk_state_show(struct device *dev,
493                                    struct device_attribute *attr, char *buf)
494 {
495         struct regulator_dev *rdev = dev_get_drvdata(dev);
496
497         return regulator_print_state(buf,
498                         rdev->constraints->state_disk.enabled);
499 }
500 static DEVICE_ATTR(suspend_disk_state, 0444,
501                 regulator_suspend_disk_state_show, NULL);
502
503 static ssize_t regulator_suspend_standby_state_show(struct device *dev,
504                                    struct device_attribute *attr, char *buf)
505 {
506         struct regulator_dev *rdev = dev_get_drvdata(dev);
507
508         return regulator_print_state(buf,
509                         rdev->constraints->state_standby.enabled);
510 }
511 static DEVICE_ATTR(suspend_standby_state, 0444,
512                 regulator_suspend_standby_state_show, NULL);
513
514
515 /*
516  * These are the only attributes are present for all regulators.
517  * Other attributes are a function of regulator functionality.
518  */
519 static struct device_attribute regulator_dev_attrs[] = {
520         __ATTR(name, 0444, regulator_name_show, NULL),
521         __ATTR(num_users, 0444, regulator_num_users_show, NULL),
522         __ATTR(type, 0444, regulator_type_show, NULL),
523         __ATTR_NULL,
524 };
525
526 static void regulator_dev_release(struct device *dev)
527 {
528         struct regulator_dev *rdev = dev_get_drvdata(dev);
529         kfree(rdev);
530 }
531
532 static struct class regulator_class = {
533         .name = "regulator",
534         .dev_release = regulator_dev_release,
535         .dev_attrs = regulator_dev_attrs,
536 };
537
538 /* Calculate the new optimum regulator operating mode based on the new total
539  * consumer load. All locks held by caller */
540 static void drms_uA_update(struct regulator_dev *rdev)
541 {
542         struct regulator *sibling;
543         int current_uA = 0, output_uV, input_uV, err;
544         unsigned int mode;
545
546         err = regulator_check_drms(rdev);
547         if (err < 0 || !rdev->desc->ops->get_optimum_mode ||
548             !rdev->desc->ops->get_voltage || !rdev->desc->ops->set_mode)
549                 return;
550
551         /* get output voltage */
552         output_uV = rdev->desc->ops->get_voltage(rdev);
553         if (output_uV <= 0)
554                 return;
555
556         /* get input voltage */
557         if (rdev->supply && rdev->supply->desc->ops->get_voltage)
558                 input_uV = rdev->supply->desc->ops->get_voltage(rdev->supply);
559         else
560                 input_uV = rdev->constraints->input_uV;
561         if (input_uV <= 0)
562                 return;
563
564         /* calc total requested load */
565         list_for_each_entry(sibling, &rdev->consumer_list, list)
566             current_uA += sibling->uA_load;
567
568         /* now get the optimum mode for our new total regulator load */
569         mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
570                                                   output_uV, current_uA);
571
572         /* check the new mode is allowed */
573         err = regulator_check_mode(rdev, mode);
574         if (err == 0)
575                 rdev->desc->ops->set_mode(rdev, mode);
576 }
577
578 static int suspend_set_state(struct regulator_dev *rdev,
579         struct regulator_state *rstate)
580 {
581         int ret = 0;
582
583         /* enable & disable are mandatory for suspend control */
584         if (!rdev->desc->ops->set_suspend_enable ||
585                 !rdev->desc->ops->set_suspend_disable) {
586                 printk(KERN_ERR "%s: no way to set suspend state\n",
587                         __func__);
588                 return -EINVAL;
589         }
590
591         if (rstate->enabled)
592                 ret = rdev->desc->ops->set_suspend_enable(rdev);
593         else
594                 ret = rdev->desc->ops->set_suspend_disable(rdev);
595         if (ret < 0) {
596                 printk(KERN_ERR "%s: failed to enabled/disable\n", __func__);
597                 return ret;
598         }
599
600         if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
601                 ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
602                 if (ret < 0) {
603                         printk(KERN_ERR "%s: failed to set voltage\n",
604                                 __func__);
605                         return ret;
606                 }
607         }
608
609         if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
610                 ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
611                 if (ret < 0) {
612                         printk(KERN_ERR "%s: failed to set mode\n", __func__);
613                         return ret;
614                 }
615         }
616         return ret;
617 }
618
619 /* locks held by caller */
620 static int suspend_prepare(struct regulator_dev *rdev, suspend_state_t state)
621 {
622         if (!rdev->constraints)
623                 return -EINVAL;
624
625         switch (state) {
626         case PM_SUSPEND_STANDBY:
627                 return suspend_set_state(rdev,
628                         &rdev->constraints->state_standby);
629         case PM_SUSPEND_MEM:
630                 return suspend_set_state(rdev,
631                         &rdev->constraints->state_mem);
632         case PM_SUSPEND_MAX:
633                 return suspend_set_state(rdev,
634                         &rdev->constraints->state_disk);
635         default:
636                 return -EINVAL;
637         }
638 }
639
640 static void print_constraints(struct regulator_dev *rdev)
641 {
642         struct regulation_constraints *constraints = rdev->constraints;
643         char buf[80];
644         int count;
645
646         if (rdev->desc->type == REGULATOR_VOLTAGE) {
647                 if (constraints->min_uV == constraints->max_uV)
648                         count = sprintf(buf, "%d mV ",
649                                         constraints->min_uV / 1000);
650                 else
651                         count = sprintf(buf, "%d <--> %d mV ",
652                                         constraints->min_uV / 1000,
653                                         constraints->max_uV / 1000);
654         } else {
655                 if (constraints->min_uA == constraints->max_uA)
656                         count = sprintf(buf, "%d mA ",
657                                         constraints->min_uA / 1000);
658                 else
659                         count = sprintf(buf, "%d <--> %d mA ",
660                                         constraints->min_uA / 1000,
661                                         constraints->max_uA / 1000);
662         }
663         if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
664                 count += sprintf(buf + count, "fast ");
665         if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
666                 count += sprintf(buf + count, "normal ");
667         if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
668                 count += sprintf(buf + count, "idle ");
669         if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
670                 count += sprintf(buf + count, "standby");
671
672         printk(KERN_INFO "regulator: %s: %s\n", rdev->desc->name, buf);
673 }
674
675 /**
676  * set_machine_constraints - sets regulator constraints
677  * @rdev: regulator source
678  * @constraints: constraints to apply
679  *
680  * Allows platform initialisation code to define and constrain
681  * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
682  * Constraints *must* be set by platform code in order for some
683  * regulator operations to proceed i.e. set_voltage, set_current_limit,
684  * set_mode.
685  */
686 static int set_machine_constraints(struct regulator_dev *rdev,
687         struct regulation_constraints *constraints)
688 {
689         int ret = 0;
690         const char *name;
691         struct regulator_ops *ops = rdev->desc->ops;
692
693         if (constraints->name)
694                 name = constraints->name;
695         else if (rdev->desc->name)
696                 name = rdev->desc->name;
697         else
698                 name = "regulator";
699
700         /* constrain machine-level voltage specs to fit
701          * the actual range supported by this regulator.
702          */
703         if (ops->list_voltage && rdev->desc->n_voltages) {
704                 int     count = rdev->desc->n_voltages;
705                 int     i;
706                 int     min_uV = INT_MAX;
707                 int     max_uV = INT_MIN;
708                 int     cmin = constraints->min_uV;
709                 int     cmax = constraints->max_uV;
710
711                 /* it's safe to autoconfigure fixed-voltage supplies
712                    and the constraints are used by list_voltage. */
713                 if (count == 1 && !cmin) {
714                         cmin = 1;
715                         cmax = INT_MAX;
716                         constraints->min_uV = cmin;
717                         constraints->max_uV = cmax;
718                 }
719
720                 /* voltage constraints are optional */
721                 if ((cmin == 0) && (cmax == 0))
722                         goto out;
723
724                 /* else require explicit machine-level constraints */
725                 if (cmin <= 0 || cmax <= 0 || cmax < cmin) {
726                         pr_err("%s: %s '%s' voltage constraints\n",
727                                        __func__, "invalid", name);
728                         ret = -EINVAL;
729                         goto out;
730                 }
731
732                 /* initial: [cmin..cmax] valid, [min_uV..max_uV] not */
733                 for (i = 0; i < count; i++) {
734                         int     value;
735
736                         value = ops->list_voltage(rdev, i);
737                         if (value <= 0)
738                                 continue;
739
740                         /* maybe adjust [min_uV..max_uV] */
741                         if (value >= cmin && value < min_uV)
742                                 min_uV = value;
743                         if (value <= cmax && value > max_uV)
744                                 max_uV = value;
745                 }
746
747                 /* final: [min_uV..max_uV] valid iff constraints valid */
748                 if (max_uV < min_uV) {
749                         pr_err("%s: %s '%s' voltage constraints\n",
750                                        __func__, "unsupportable", name);
751                         ret = -EINVAL;
752                         goto out;
753                 }
754
755                 /* use regulator's subset of machine constraints */
756                 if (constraints->min_uV < min_uV) {
757                         pr_debug("%s: override '%s' %s, %d -> %d\n",
758                                        __func__, name, "min_uV",
759                                         constraints->min_uV, min_uV);
760                         constraints->min_uV = min_uV;
761                 }
762                 if (constraints->max_uV > max_uV) {
763                         pr_debug("%s: override '%s' %s, %d -> %d\n",
764                                        __func__, name, "max_uV",
765                                         constraints->max_uV, max_uV);
766                         constraints->max_uV = max_uV;
767                 }
768         }
769
770         rdev->constraints = constraints;
771
772         /* do we need to apply the constraint voltage */
773         if (rdev->constraints->apply_uV &&
774                 rdev->constraints->min_uV == rdev->constraints->max_uV &&
775                 ops->set_voltage) {
776                 ret = ops->set_voltage(rdev,
777                         rdev->constraints->min_uV, rdev->constraints->max_uV);
778                         if (ret < 0) {
779                                 printk(KERN_ERR "%s: failed to apply %duV constraint to %s\n",
780                                        __func__,
781                                        rdev->constraints->min_uV, name);
782                                 rdev->constraints = NULL;
783                                 goto out;
784                         }
785         }
786
787         /* do we need to setup our suspend state */
788         if (constraints->initial_state) {
789                 ret = suspend_prepare(rdev, constraints->initial_state);
790                 if (ret < 0) {
791                         printk(KERN_ERR "%s: failed to set suspend state for %s\n",
792                                __func__, name);
793                         rdev->constraints = NULL;
794                         goto out;
795                 }
796         }
797
798         if (constraints->initial_mode) {
799                 if (!ops->set_mode) {
800                         printk(KERN_ERR "%s: no set_mode operation for %s\n",
801                                __func__, name);
802                         ret = -EINVAL;
803                         goto out;
804                 }
805
806                 ret = ops->set_mode(rdev, constraints->initial_mode);
807                 if (ret < 0) {
808                         printk(KERN_ERR
809                                "%s: failed to set initial mode for %s: %d\n",
810                                __func__, name, ret);
811                         goto out;
812                 }
813         }
814
815         /* If the constraints say the regulator should be on at this point
816          * and we have control then make sure it is enabled.
817          */
818         if ((constraints->always_on || constraints->boot_on) && ops->enable) {
819                 ret = ops->enable(rdev);
820                 if (ret < 0) {
821                         printk(KERN_ERR "%s: failed to enable %s\n",
822                                __func__, name);
823                         rdev->constraints = NULL;
824                         goto out;
825                 }
826         }
827
828         print_constraints(rdev);
829 out:
830         return ret;
831 }
832
833 /**
834  * set_supply - set regulator supply regulator
835  * @rdev: regulator name
836  * @supply_rdev: supply regulator name
837  *
838  * Called by platform initialisation code to set the supply regulator for this
839  * regulator. This ensures that a regulators supply will also be enabled by the
840  * core if it's child is enabled.
841  */
842 static int set_supply(struct regulator_dev *rdev,
843         struct regulator_dev *supply_rdev)
844 {
845         int err;
846
847         err = sysfs_create_link(&rdev->dev.kobj, &supply_rdev->dev.kobj,
848                                 "supply");
849         if (err) {
850                 printk(KERN_ERR
851                        "%s: could not add device link %s err %d\n",
852                        __func__, supply_rdev->dev.kobj.name, err);
853                        goto out;
854         }
855         rdev->supply = supply_rdev;
856         list_add(&rdev->slist, &supply_rdev->supply_list);
857 out:
858         return err;
859 }
860
861 /**
862  * set_consumer_device_supply: Bind a regulator to a symbolic supply
863  * @rdev:         regulator source
864  * @consumer_dev: device the supply applies to
865  * @consumer_dev_name: dev_name() string for device supply applies to
866  * @supply:       symbolic name for supply
867  *
868  * Allows platform initialisation code to map physical regulator
869  * sources to symbolic names for supplies for use by devices.  Devices
870  * should use these symbolic names to request regulators, avoiding the
871  * need to provide board-specific regulator names as platform data.
872  *
873  * Only one of consumer_dev and consumer_dev_name may be specified.
874  */
875 static int set_consumer_device_supply(struct regulator_dev *rdev,
876         struct device *consumer_dev, const char *consumer_dev_name,
877         const char *supply)
878 {
879         struct regulator_map *node;
880         int has_dev;
881
882         if (consumer_dev && consumer_dev_name)
883                 return -EINVAL;
884
885         if (!consumer_dev_name && consumer_dev)
886                 consumer_dev_name = dev_name(consumer_dev);
887
888         if (supply == NULL)
889                 return -EINVAL;
890
891         if (consumer_dev_name != NULL)
892                 has_dev = 1;
893         else
894                 has_dev = 0;
895
896         list_for_each_entry(node, &regulator_map_list, list) {
897                 if (consumer_dev_name != node->dev_name)
898                         continue;
899                 if (strcmp(node->supply, supply) != 0)
900                         continue;
901
902                 dev_dbg(consumer_dev, "%s/%s is '%s' supply; fail %s/%s\n",
903                                 dev_name(&node->regulator->dev),
904                                 node->regulator->desc->name,
905                                 supply,
906                                 dev_name(&rdev->dev), rdev->desc->name);
907                 return -EBUSY;
908         }
909
910         node = kzalloc(sizeof(struct regulator_map), GFP_KERNEL);
911         if (node == NULL)
912                 return -ENOMEM;
913
914         node->regulator = rdev;
915         node->supply = supply;
916
917         if (has_dev) {
918                 node->dev_name = kstrdup(consumer_dev_name, GFP_KERNEL);
919                 if (node->dev_name == NULL) {
920                         kfree(node);
921                         return -ENOMEM;
922                 }
923         }
924
925         list_add(&node->list, &regulator_map_list);
926         return 0;
927 }
928
929 static void unset_consumer_device_supply(struct regulator_dev *rdev,
930         const char *consumer_dev_name, struct device *consumer_dev)
931 {
932         struct regulator_map *node, *n;
933
934         if (consumer_dev && !consumer_dev_name)
935                 consumer_dev_name = dev_name(consumer_dev);
936
937         list_for_each_entry_safe(node, n, &regulator_map_list, list) {
938                 if (rdev != node->regulator)
939                         continue;
940
941                 if (consumer_dev_name && node->dev_name &&
942                     strcmp(consumer_dev_name, node->dev_name))
943                         continue;
944
945                 list_del(&node->list);
946                 kfree(node->dev_name);
947                 kfree(node);
948                 return;
949         }
950 }
951
952 static void unset_regulator_supplies(struct regulator_dev *rdev)
953 {
954         struct regulator_map *node, *n;
955
956         list_for_each_entry_safe(node, n, &regulator_map_list, list) {
957                 if (rdev == node->regulator) {
958                         list_del(&node->list);
959                         kfree(node->dev_name);
960                         kfree(node);
961                         return;
962                 }
963         }
964 }
965
966 #define REG_STR_SIZE    32
967
968 static struct regulator *create_regulator(struct regulator_dev *rdev,
969                                           struct device *dev,
970                                           const char *supply_name)
971 {
972         struct regulator *regulator;
973         char buf[REG_STR_SIZE];
974         int err, size;
975
976         regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
977         if (regulator == NULL)
978                 return NULL;
979
980         mutex_lock(&rdev->mutex);
981         regulator->rdev = rdev;
982         list_add(&regulator->list, &rdev->consumer_list);
983
984         if (dev) {
985                 /* create a 'requested_microamps_name' sysfs entry */
986                 size = scnprintf(buf, REG_STR_SIZE, "microamps_requested_%s",
987                         supply_name);
988                 if (size >= REG_STR_SIZE)
989                         goto overflow_err;
990
991                 regulator->dev = dev;
992                 regulator->dev_attr.attr.name = kstrdup(buf, GFP_KERNEL);
993                 if (regulator->dev_attr.attr.name == NULL)
994                         goto attr_name_err;
995
996                 regulator->dev_attr.attr.owner = THIS_MODULE;
997                 regulator->dev_attr.attr.mode = 0444;
998                 regulator->dev_attr.show = device_requested_uA_show;
999                 err = device_create_file(dev, &regulator->dev_attr);
1000                 if (err < 0) {
1001                         printk(KERN_WARNING "%s: could not add regulator_dev"
1002                                 " load sysfs\n", __func__);
1003                         goto attr_name_err;
1004                 }
1005
1006                 /* also add a link to the device sysfs entry */
1007                 size = scnprintf(buf, REG_STR_SIZE, "%s-%s",
1008                                  dev->kobj.name, supply_name);
1009                 if (size >= REG_STR_SIZE)
1010                         goto attr_err;
1011
1012                 regulator->supply_name = kstrdup(buf, GFP_KERNEL);
1013                 if (regulator->supply_name == NULL)
1014                         goto attr_err;
1015
1016                 err = sysfs_create_link(&rdev->dev.kobj, &dev->kobj,
1017                                         buf);
1018                 if (err) {
1019                         printk(KERN_WARNING
1020                                "%s: could not add device link %s err %d\n",
1021                                __func__, dev->kobj.name, err);
1022                         device_remove_file(dev, &regulator->dev_attr);
1023                         goto link_name_err;
1024                 }
1025         }
1026         mutex_unlock(&rdev->mutex);
1027         return regulator;
1028 link_name_err:
1029         kfree(regulator->supply_name);
1030 attr_err:
1031         device_remove_file(regulator->dev, &regulator->dev_attr);
1032 attr_name_err:
1033         kfree(regulator->dev_attr.attr.name);
1034 overflow_err:
1035         list_del(&regulator->list);
1036         kfree(regulator);
1037         mutex_unlock(&rdev->mutex);
1038         return NULL;
1039 }
1040
1041 /* Internal regulator request function */
1042 static struct regulator *_regulator_get(struct device *dev, const char *id,
1043                                         int exclusive)
1044 {
1045         struct regulator_dev *rdev;
1046         struct regulator_map *map;
1047         struct regulator *regulator = ERR_PTR(-ENODEV);
1048         const char *devname = NULL;
1049         int ret;
1050
1051         if (id == NULL) {
1052                 printk(KERN_ERR "regulator: get() with no identifier\n");
1053                 return regulator;
1054         }
1055
1056         if (dev)
1057                 devname = dev_name(dev);
1058
1059         mutex_lock(&regulator_list_mutex);
1060
1061         list_for_each_entry(map, &regulator_map_list, list) {
1062                 /* If the mapping has a device set up it must match */
1063                 if (map->dev_name &&
1064                     (!devname || strcmp(map->dev_name, devname)))
1065                         continue;
1066
1067                 if (strcmp(map->supply, id) == 0) {
1068                         rdev = map->regulator;
1069                         goto found;
1070                 }
1071         }
1072         mutex_unlock(&regulator_list_mutex);
1073         return regulator;
1074
1075 found:
1076         if (rdev->exclusive) {
1077                 regulator = ERR_PTR(-EPERM);
1078                 goto out;
1079         }
1080
1081         if (exclusive && rdev->open_count) {
1082                 regulator = ERR_PTR(-EBUSY);
1083                 goto out;
1084         }
1085
1086         if (!try_module_get(rdev->owner))
1087                 goto out;
1088
1089         regulator = create_regulator(rdev, dev, id);
1090         if (regulator == NULL) {
1091                 regulator = ERR_PTR(-ENOMEM);
1092                 module_put(rdev->owner);
1093         }
1094
1095         rdev->open_count++;
1096         if (exclusive) {
1097                 rdev->exclusive = 1;
1098
1099                 ret = _regulator_is_enabled(rdev);
1100                 if (ret > 0)
1101                         rdev->use_count = 1;
1102                 else
1103                         rdev->use_count = 0;
1104         }
1105
1106 out:
1107         mutex_unlock(&regulator_list_mutex);
1108
1109         return regulator;
1110 }
1111
1112 /**
1113  * regulator_get - lookup and obtain a reference to a regulator.
1114  * @dev: device for regulator "consumer"
1115  * @id: Supply name or regulator ID.
1116  *
1117  * Returns a struct regulator corresponding to the regulator producer,
1118  * or IS_ERR() condition containing errno.
1119  *
1120  * Use of supply names configured via regulator_set_device_supply() is
1121  * strongly encouraged.  It is recommended that the supply name used
1122  * should match the name used for the supply and/or the relevant
1123  * device pins in the datasheet.
1124  */
1125 struct regulator *regulator_get(struct device *dev, const char *id)
1126 {
1127         return _regulator_get(dev, id, 0);
1128 }
1129 EXPORT_SYMBOL_GPL(regulator_get);
1130
1131 /**
1132  * regulator_get_exclusive - obtain exclusive access to a regulator.
1133  * @dev: device for regulator "consumer"
1134  * @id: Supply name or regulator ID.
1135  *
1136  * Returns a struct regulator corresponding to the regulator producer,
1137  * or IS_ERR() condition containing errno.  Other consumers will be
1138  * unable to obtain this reference is held and the use count for the
1139  * regulator will be initialised to reflect the current state of the
1140  * regulator.
1141  *
1142  * This is intended for use by consumers which cannot tolerate shared
1143  * use of the regulator such as those which need to force the
1144  * regulator off for correct operation of the hardware they are
1145  * controlling.
1146  *
1147  * Use of supply names configured via regulator_set_device_supply() is
1148  * strongly encouraged.  It is recommended that the supply name used
1149  * should match the name used for the supply and/or the relevant
1150  * device pins in the datasheet.
1151  */
1152 struct regulator *regulator_get_exclusive(struct device *dev, const char *id)
1153 {
1154         return _regulator_get(dev, id, 1);
1155 }
1156 EXPORT_SYMBOL_GPL(regulator_get_exclusive);
1157
1158 /**
1159  * regulator_put - "free" the regulator source
1160  * @regulator: regulator source
1161  *
1162  * Note: drivers must ensure that all regulator_enable calls made on this
1163  * regulator source are balanced by regulator_disable calls prior to calling
1164  * this function.
1165  */
1166 void regulator_put(struct regulator *regulator)
1167 {
1168         struct regulator_dev *rdev;
1169
1170         if (regulator == NULL || IS_ERR(regulator))
1171                 return;
1172
1173         mutex_lock(&regulator_list_mutex);
1174         rdev = regulator->rdev;
1175
1176         /* remove any sysfs entries */
1177         if (regulator->dev) {
1178                 sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
1179                 kfree(regulator->supply_name);
1180                 device_remove_file(regulator->dev, &regulator->dev_attr);
1181                 kfree(regulator->dev_attr.attr.name);
1182         }
1183         list_del(&regulator->list);
1184         kfree(regulator);
1185
1186         rdev->open_count--;
1187         rdev->exclusive = 0;
1188
1189         module_put(rdev->owner);
1190         mutex_unlock(&regulator_list_mutex);
1191 }
1192 EXPORT_SYMBOL_GPL(regulator_put);
1193
1194 static int _regulator_can_change_status(struct regulator_dev *rdev)
1195 {
1196         if (!rdev->constraints)
1197                 return 0;
1198
1199         if (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_STATUS)
1200                 return 1;
1201         else
1202                 return 0;
1203 }
1204
1205 /* locks held by regulator_enable() */
1206 static int _regulator_enable(struct regulator_dev *rdev)
1207 {
1208         int ret;
1209
1210         /* do we need to enable the supply regulator first */
1211         if (rdev->supply) {
1212                 ret = _regulator_enable(rdev->supply);
1213                 if (ret < 0) {
1214                         printk(KERN_ERR "%s: failed to enable %s: %d\n",
1215                                __func__, rdev->desc->name, ret);
1216                         return ret;
1217                 }
1218         }
1219
1220         /* check voltage and requested load before enabling */
1221         if (rdev->constraints &&
1222             (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS))
1223                 drms_uA_update(rdev);
1224
1225         if (rdev->use_count == 0) {
1226                 /* The regulator may on if it's not switchable or left on */
1227                 ret = _regulator_is_enabled(rdev);
1228                 if (ret == -EINVAL || ret == 0) {
1229                         if (!_regulator_can_change_status(rdev))
1230                                 return -EPERM;
1231
1232                         if (rdev->desc->ops->enable) {
1233                                 ret = rdev->desc->ops->enable(rdev);
1234                                 if (ret < 0)
1235                                         return ret;
1236                         } else {
1237                                 return -EINVAL;
1238                         }
1239                 } else if (ret < 0) {
1240                         printk(KERN_ERR "%s: is_enabled() failed for %s: %d\n",
1241                                __func__, rdev->desc->name, ret);
1242                         return ret;
1243                 }
1244                 /* Fallthrough on positive return values - already enabled */
1245         }
1246
1247         rdev->use_count++;
1248
1249         return 0;
1250 }
1251
1252 /**
1253  * regulator_enable - enable regulator output
1254  * @regulator: regulator source
1255  *
1256  * Request that the regulator be enabled with the regulator output at
1257  * the predefined voltage or current value.  Calls to regulator_enable()
1258  * must be balanced with calls to regulator_disable().
1259  *
1260  * NOTE: the output value can be set by other drivers, boot loader or may be
1261  * hardwired in the regulator.
1262  */
1263 int regulator_enable(struct regulator *regulator)
1264 {
1265         struct regulator_dev *rdev = regulator->rdev;
1266         int ret = 0;
1267
1268         mutex_lock(&rdev->mutex);
1269         ret = _regulator_enable(rdev);
1270         mutex_unlock(&rdev->mutex);
1271         return ret;
1272 }
1273 EXPORT_SYMBOL_GPL(regulator_enable);
1274
1275 /* locks held by regulator_disable() */
1276 static int _regulator_disable(struct regulator_dev *rdev)
1277 {
1278         int ret = 0;
1279
1280         if (WARN(rdev->use_count <= 0,
1281                         "unbalanced disables for %s\n",
1282                         rdev->desc->name))
1283                 return -EIO;
1284
1285         /* are we the last user and permitted to disable ? */
1286         if (rdev->use_count == 1 &&
1287             (rdev->constraints && !rdev->constraints->always_on)) {
1288
1289                 /* we are last user */
1290                 if (_regulator_can_change_status(rdev) &&
1291                     rdev->desc->ops->disable) {
1292                         ret = rdev->desc->ops->disable(rdev);
1293                         if (ret < 0) {
1294                                 printk(KERN_ERR "%s: failed to disable %s\n",
1295                                        __func__, rdev->desc->name);
1296                                 return ret;
1297                         }
1298                 }
1299
1300                 /* decrease our supplies ref count and disable if required */
1301                 if (rdev->supply)
1302                         _regulator_disable(rdev->supply);
1303
1304                 rdev->use_count = 0;
1305         } else if (rdev->use_count > 1) {
1306
1307                 if (rdev->constraints &&
1308                         (rdev->constraints->valid_ops_mask &
1309                         REGULATOR_CHANGE_DRMS))
1310                         drms_uA_update(rdev);
1311
1312                 rdev->use_count--;
1313         }
1314         return ret;
1315 }
1316
1317 /**
1318  * regulator_disable - disable regulator output
1319  * @regulator: regulator source
1320  *
1321  * Disable the regulator output voltage or current.  Calls to
1322  * regulator_enable() must be balanced with calls to
1323  * regulator_disable().
1324  *
1325  * NOTE: this will only disable the regulator output if no other consumer
1326  * devices have it enabled, the regulator device supports disabling and
1327  * machine constraints permit this operation.
1328  */
1329 int regulator_disable(struct regulator *regulator)
1330 {
1331         struct regulator_dev *rdev = regulator->rdev;
1332         int ret = 0;
1333
1334         mutex_lock(&rdev->mutex);
1335         ret = _regulator_disable(rdev);
1336         mutex_unlock(&rdev->mutex);
1337         return ret;
1338 }
1339 EXPORT_SYMBOL_GPL(regulator_disable);
1340
1341 /* locks held by regulator_force_disable() */
1342 static int _regulator_force_disable(struct regulator_dev *rdev)
1343 {
1344         int ret = 0;
1345
1346         /* force disable */
1347         if (rdev->desc->ops->disable) {
1348                 /* ah well, who wants to live forever... */
1349                 ret = rdev->desc->ops->disable(rdev);
1350                 if (ret < 0) {
1351                         printk(KERN_ERR "%s: failed to force disable %s\n",
1352                                __func__, rdev->desc->name);
1353                         return ret;
1354                 }
1355                 /* notify other consumers that power has been forced off */
1356                 _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE,
1357                         NULL);
1358         }
1359
1360         /* decrease our supplies ref count and disable if required */
1361         if (rdev->supply)
1362                 _regulator_disable(rdev->supply);
1363
1364         rdev->use_count = 0;
1365         return ret;
1366 }
1367
1368 /**
1369  * regulator_force_disable - force disable regulator output
1370  * @regulator: regulator source
1371  *
1372  * Forcibly disable the regulator output voltage or current.
1373  * NOTE: this *will* disable the regulator output even if other consumer
1374  * devices have it enabled. This should be used for situations when device
1375  * damage will likely occur if the regulator is not disabled (e.g. over temp).
1376  */
1377 int regulator_force_disable(struct regulator *regulator)
1378 {
1379         int ret;
1380
1381         mutex_lock(&regulator->rdev->mutex);
1382         regulator->uA_load = 0;
1383         ret = _regulator_force_disable(regulator->rdev);
1384         mutex_unlock(&regulator->rdev->mutex);
1385         return ret;
1386 }
1387 EXPORT_SYMBOL_GPL(regulator_force_disable);
1388
1389 static int _regulator_is_enabled(struct regulator_dev *rdev)
1390 {
1391         /* sanity check */
1392         if (!rdev->desc->ops->is_enabled)
1393                 return -EINVAL;
1394
1395         return rdev->desc->ops->is_enabled(rdev);
1396 }
1397
1398 /**
1399  * regulator_is_enabled - is the regulator output enabled
1400  * @regulator: regulator source
1401  *
1402  * Returns positive if the regulator driver backing the source/client
1403  * has requested that the device be enabled, zero if it hasn't, else a
1404  * negative errno code.
1405  *
1406  * Note that the device backing this regulator handle can have multiple
1407  * users, so it might be enabled even if regulator_enable() was never
1408  * called for this particular source.
1409  */
1410 int regulator_is_enabled(struct regulator *regulator)
1411 {
1412         int ret;
1413
1414         mutex_lock(&regulator->rdev->mutex);
1415         ret = _regulator_is_enabled(regulator->rdev);
1416         mutex_unlock(&regulator->rdev->mutex);
1417
1418         return ret;
1419 }
1420 EXPORT_SYMBOL_GPL(regulator_is_enabled);
1421
1422 /**
1423  * regulator_count_voltages - count regulator_list_voltage() selectors
1424  * @regulator: regulator source
1425  *
1426  * Returns number of selectors, or negative errno.  Selectors are
1427  * numbered starting at zero, and typically correspond to bitfields
1428  * in hardware registers.
1429  */
1430 int regulator_count_voltages(struct regulator *regulator)
1431 {
1432         struct regulator_dev    *rdev = regulator->rdev;
1433
1434         return rdev->desc->n_voltages ? : -EINVAL;
1435 }
1436 EXPORT_SYMBOL_GPL(regulator_count_voltages);
1437
1438 /**
1439  * regulator_list_voltage - enumerate supported voltages
1440  * @regulator: regulator source
1441  * @selector: identify voltage to list
1442  * Context: can sleep
1443  *
1444  * Returns a voltage that can be passed to @regulator_set_voltage(),
1445  * zero if this selector code can't be used on this sytem, or a
1446  * negative errno.
1447  */
1448 int regulator_list_voltage(struct regulator *regulator, unsigned selector)
1449 {
1450         struct regulator_dev    *rdev = regulator->rdev;
1451         struct regulator_ops    *ops = rdev->desc->ops;
1452         int                     ret;
1453
1454         if (!ops->list_voltage || selector >= rdev->desc->n_voltages)
1455                 return -EINVAL;
1456
1457         mutex_lock(&rdev->mutex);
1458         ret = ops->list_voltage(rdev, selector);
1459         mutex_unlock(&rdev->mutex);
1460
1461         if (ret > 0) {
1462                 if (ret < rdev->constraints->min_uV)
1463                         ret = 0;
1464                 else if (ret > rdev->constraints->max_uV)
1465                         ret = 0;
1466         }
1467
1468         return ret;
1469 }
1470 EXPORT_SYMBOL_GPL(regulator_list_voltage);
1471
1472 /**
1473  * regulator_is_supported_voltage - check if a voltage range can be supported
1474  *
1475  * @regulator: Regulator to check.
1476  * @min_uV: Minimum required voltage in uV.
1477  * @max_uV: Maximum required voltage in uV.
1478  *
1479  * Returns a boolean or a negative error code.
1480  */
1481 int regulator_is_supported_voltage(struct regulator *regulator,
1482                                    int min_uV, int max_uV)
1483 {
1484         int i, voltages, ret;
1485
1486         ret = regulator_count_voltages(regulator);
1487         if (ret < 0)
1488                 return ret;
1489         voltages = ret;
1490
1491         for (i = 0; i < voltages; i++) {
1492                 ret = regulator_list_voltage(regulator, i);
1493
1494                 if (ret >= min_uV && ret <= max_uV)
1495                         return 1;
1496         }
1497
1498         return 0;
1499 }
1500
1501 /**
1502  * regulator_set_voltage - set regulator output voltage
1503  * @regulator: regulator source
1504  * @min_uV: Minimum required voltage in uV
1505  * @max_uV: Maximum acceptable voltage in uV
1506  *
1507  * Sets a voltage regulator to the desired output voltage. This can be set
1508  * during any regulator state. IOW, regulator can be disabled or enabled.
1509  *
1510  * If the regulator is enabled then the voltage will change to the new value
1511  * immediately otherwise if the regulator is disabled the regulator will
1512  * output at the new voltage when enabled.
1513  *
1514  * NOTE: If the regulator is shared between several devices then the lowest
1515  * request voltage that meets the system constraints will be used.
1516  * Regulator system constraints must be set for this regulator before
1517  * calling this function otherwise this call will fail.
1518  */
1519 int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
1520 {
1521         struct regulator_dev *rdev = regulator->rdev;
1522         int ret;
1523
1524         mutex_lock(&rdev->mutex);
1525
1526         /* sanity check */
1527         if (!rdev->desc->ops->set_voltage) {
1528                 ret = -EINVAL;
1529                 goto out;
1530         }
1531
1532         /* constraints check */
1533         ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
1534         if (ret < 0)
1535                 goto out;
1536         regulator->min_uV = min_uV;
1537         regulator->max_uV = max_uV;
1538         ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV);
1539
1540 out:
1541         _notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE, NULL);
1542         mutex_unlock(&rdev->mutex);
1543         return ret;
1544 }
1545 EXPORT_SYMBOL_GPL(regulator_set_voltage);
1546
1547 static int _regulator_get_voltage(struct regulator_dev *rdev)
1548 {
1549         /* sanity check */
1550         if (rdev->desc->ops->get_voltage)
1551                 return rdev->desc->ops->get_voltage(rdev);
1552         else
1553                 return -EINVAL;
1554 }
1555
1556 /**
1557  * regulator_get_voltage - get regulator output voltage
1558  * @regulator: regulator source
1559  *
1560  * This returns the current regulator voltage in uV.
1561  *
1562  * NOTE: If the regulator is disabled it will return the voltage value. This
1563  * function should not be used to determine regulator state.
1564  */
1565 int regulator_get_voltage(struct regulator *regulator)
1566 {
1567         int ret;
1568
1569         mutex_lock(&regulator->rdev->mutex);
1570
1571         ret = _regulator_get_voltage(regulator->rdev);
1572
1573         mutex_unlock(&regulator->rdev->mutex);
1574
1575         return ret;
1576 }
1577 EXPORT_SYMBOL_GPL(regulator_get_voltage);
1578
1579 /**
1580  * regulator_set_current_limit - set regulator output current limit
1581  * @regulator: regulator source
1582  * @min_uA: Minimuum supported current in uA
1583  * @max_uA: Maximum supported current in uA
1584  *
1585  * Sets current sink to the desired output current. This can be set during
1586  * any regulator state. IOW, regulator can be disabled or enabled.
1587  *
1588  * If the regulator is enabled then the current will change to the new value
1589  * immediately otherwise if the regulator is disabled the regulator will
1590  * output at the new current when enabled.
1591  *
1592  * NOTE: Regulator system constraints must be set for this regulator before
1593  * calling this function otherwise this call will fail.
1594  */
1595 int regulator_set_current_limit(struct regulator *regulator,
1596                                int min_uA, int max_uA)
1597 {
1598         struct regulator_dev *rdev = regulator->rdev;
1599         int ret;
1600
1601         mutex_lock(&rdev->mutex);
1602
1603         /* sanity check */
1604         if (!rdev->desc->ops->set_current_limit) {
1605                 ret = -EINVAL;
1606                 goto out;
1607         }
1608
1609         /* constraints check */
1610         ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
1611         if (ret < 0)
1612                 goto out;
1613
1614         ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
1615 out:
1616         mutex_unlock(&rdev->mutex);
1617         return ret;
1618 }
1619 EXPORT_SYMBOL_GPL(regulator_set_current_limit);
1620
1621 static int _regulator_get_current_limit(struct regulator_dev *rdev)
1622 {
1623         int ret;
1624
1625         mutex_lock(&rdev->mutex);
1626
1627         /* sanity check */
1628         if (!rdev->desc->ops->get_current_limit) {
1629                 ret = -EINVAL;
1630                 goto out;
1631         }
1632
1633         ret = rdev->desc->ops->get_current_limit(rdev);
1634 out:
1635         mutex_unlock(&rdev->mutex);
1636         return ret;
1637 }
1638
1639 /**
1640  * regulator_get_current_limit - get regulator output current
1641  * @regulator: regulator source
1642  *
1643  * This returns the current supplied by the specified current sink in uA.
1644  *
1645  * NOTE: If the regulator is disabled it will return the current value. This
1646  * function should not be used to determine regulator state.
1647  */
1648 int regulator_get_current_limit(struct regulator *regulator)
1649 {
1650         return _regulator_get_current_limit(regulator->rdev);
1651 }
1652 EXPORT_SYMBOL_GPL(regulator_get_current_limit);
1653
1654 /**
1655  * regulator_set_mode - set regulator operating mode
1656  * @regulator: regulator source
1657  * @mode: operating mode - one of the REGULATOR_MODE constants
1658  *
1659  * Set regulator operating mode to increase regulator efficiency or improve
1660  * regulation performance.
1661  *
1662  * NOTE: Regulator system constraints must be set for this regulator before
1663  * calling this function otherwise this call will fail.
1664  */
1665 int regulator_set_mode(struct regulator *regulator, unsigned int mode)
1666 {
1667         struct regulator_dev *rdev = regulator->rdev;
1668         int ret;
1669
1670         mutex_lock(&rdev->mutex);
1671
1672         /* sanity check */
1673         if (!rdev->desc->ops->set_mode) {
1674                 ret = -EINVAL;
1675                 goto out;
1676         }
1677
1678         /* constraints check */
1679         ret = regulator_check_mode(rdev, mode);
1680         if (ret < 0)
1681                 goto out;
1682
1683         ret = rdev->desc->ops->set_mode(rdev, mode);
1684 out:
1685         mutex_unlock(&rdev->mutex);
1686         return ret;
1687 }
1688 EXPORT_SYMBOL_GPL(regulator_set_mode);
1689
1690 static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
1691 {
1692         int ret;
1693
1694         mutex_lock(&rdev->mutex);
1695
1696         /* sanity check */
1697         if (!rdev->desc->ops->get_mode) {
1698                 ret = -EINVAL;
1699                 goto out;
1700         }
1701
1702         ret = rdev->desc->ops->get_mode(rdev);
1703 out:
1704         mutex_unlock(&rdev->mutex);
1705         return ret;
1706 }
1707
1708 /**
1709  * regulator_get_mode - get regulator operating mode
1710  * @regulator: regulator source
1711  *
1712  * Get the current regulator operating mode.
1713  */
1714 unsigned int regulator_get_mode(struct regulator *regulator)
1715 {
1716         return _regulator_get_mode(regulator->rdev);
1717 }
1718 EXPORT_SYMBOL_GPL(regulator_get_mode);
1719
1720 /**
1721  * regulator_set_optimum_mode - set regulator optimum operating mode
1722  * @regulator: regulator source
1723  * @uA_load: load current
1724  *
1725  * Notifies the regulator core of a new device load. This is then used by
1726  * DRMS (if enabled by constraints) to set the most efficient regulator
1727  * operating mode for the new regulator loading.
1728  *
1729  * Consumer devices notify their supply regulator of the maximum power
1730  * they will require (can be taken from device datasheet in the power
1731  * consumption tables) when they change operational status and hence power
1732  * state. Examples of operational state changes that can affect power
1733  * consumption are :-
1734  *
1735  *    o Device is opened / closed.
1736  *    o Device I/O is about to begin or has just finished.
1737  *    o Device is idling in between work.
1738  *
1739  * This information is also exported via sysfs to userspace.
1740  *
1741  * DRMS will sum the total requested load on the regulator and change
1742  * to the most efficient operating mode if platform constraints allow.
1743  *
1744  * Returns the new regulator mode or error.
1745  */
1746 int regulator_set_optimum_mode(struct regulator *regulator, int uA_load)
1747 {
1748         struct regulator_dev *rdev = regulator->rdev;
1749         struct regulator *consumer;
1750         int ret, output_uV, input_uV, total_uA_load = 0;
1751         unsigned int mode;
1752
1753         mutex_lock(&rdev->mutex);
1754
1755         regulator->uA_load = uA_load;
1756         ret = regulator_check_drms(rdev);
1757         if (ret < 0)
1758                 goto out;
1759         ret = -EINVAL;
1760
1761         /* sanity check */
1762         if (!rdev->desc->ops->get_optimum_mode)
1763                 goto out;
1764
1765         /* get output voltage */
1766         output_uV = rdev->desc->ops->get_voltage(rdev);
1767         if (output_uV <= 0) {
1768                 printk(KERN_ERR "%s: invalid output voltage found for %s\n",
1769                         __func__, rdev->desc->name);
1770                 goto out;
1771         }
1772
1773         /* get input voltage */
1774         if (rdev->supply && rdev->supply->desc->ops->get_voltage)
1775                 input_uV = rdev->supply->desc->ops->get_voltage(rdev->supply);
1776         else
1777                 input_uV = rdev->constraints->input_uV;
1778         if (input_uV <= 0) {
1779                 printk(KERN_ERR "%s: invalid input voltage found for %s\n",
1780                         __func__, rdev->desc->name);
1781                 goto out;
1782         }
1783
1784         /* calc total requested load for this regulator */
1785         list_for_each_entry(consumer, &rdev->consumer_list, list)
1786             total_uA_load += consumer->uA_load;
1787
1788         mode = rdev->desc->ops->get_optimum_mode(rdev,
1789                                                  input_uV, output_uV,
1790                                                  total_uA_load);
1791         ret = regulator_check_mode(rdev, mode);
1792         if (ret < 0) {
1793                 printk(KERN_ERR "%s: failed to get optimum mode for %s @"
1794                         " %d uA %d -> %d uV\n", __func__, rdev->desc->name,
1795                         total_uA_load, input_uV, output_uV);
1796                 goto out;
1797         }
1798
1799         ret = rdev->desc->ops->set_mode(rdev, mode);
1800         if (ret < 0) {
1801                 printk(KERN_ERR "%s: failed to set optimum mode %x for %s\n",
1802                         __func__, mode, rdev->desc->name);
1803                 goto out;
1804         }
1805         ret = mode;
1806 out:
1807         mutex_unlock(&rdev->mutex);
1808         return ret;
1809 }
1810 EXPORT_SYMBOL_GPL(regulator_set_optimum_mode);
1811
1812 /**
1813  * regulator_register_notifier - register regulator event notifier
1814  * @regulator: regulator source
1815  * @nb: notifier block
1816  *
1817  * Register notifier block to receive regulator events.
1818  */
1819 int regulator_register_notifier(struct regulator *regulator,
1820                               struct notifier_block *nb)
1821 {
1822         return blocking_notifier_chain_register(&regulator->rdev->notifier,
1823                                                 nb);
1824 }
1825 EXPORT_SYMBOL_GPL(regulator_register_notifier);
1826
1827 /**
1828  * regulator_unregister_notifier - unregister regulator event notifier
1829  * @regulator: regulator source
1830  * @nb: notifier block
1831  *
1832  * Unregister regulator event notifier block.
1833  */
1834 int regulator_unregister_notifier(struct regulator *regulator,
1835                                 struct notifier_block *nb)
1836 {
1837         return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
1838                                                   nb);
1839 }
1840 EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
1841
1842 /* notify regulator consumers and downstream regulator consumers.
1843  * Note mutex must be held by caller.
1844  */
1845 static void _notifier_call_chain(struct regulator_dev *rdev,
1846                                   unsigned long event, void *data)
1847 {
1848         struct regulator_dev *_rdev;
1849
1850         /* call rdev chain first */
1851         blocking_notifier_call_chain(&rdev->notifier, event, NULL);
1852
1853         /* now notify regulator we supply */
1854         list_for_each_entry(_rdev, &rdev->supply_list, slist) {
1855           mutex_lock(&_rdev->mutex);
1856           _notifier_call_chain(_rdev, event, data);
1857           mutex_unlock(&_rdev->mutex);
1858         }
1859 }
1860
1861 /**
1862  * regulator_bulk_get - get multiple regulator consumers
1863  *
1864  * @dev:           Device to supply
1865  * @num_consumers: Number of consumers to register
1866  * @consumers:     Configuration of consumers; clients are stored here.
1867  *
1868  * @return 0 on success, an errno on failure.
1869  *
1870  * This helper function allows drivers to get several regulator
1871  * consumers in one operation.  If any of the regulators cannot be
1872  * acquired then any regulators that were allocated will be freed
1873  * before returning to the caller.
1874  */
1875 int regulator_bulk_get(struct device *dev, int num_consumers,
1876                        struct regulator_bulk_data *consumers)
1877 {
1878         int i;
1879         int ret;
1880
1881         for (i = 0; i < num_consumers; i++)
1882                 consumers[i].consumer = NULL;
1883
1884         for (i = 0; i < num_consumers; i++) {
1885                 consumers[i].consumer = regulator_get(dev,
1886                                                       consumers[i].supply);
1887                 if (IS_ERR(consumers[i].consumer)) {
1888                         dev_err(dev, "Failed to get supply '%s'\n",
1889                                 consumers[i].supply);
1890                         ret = PTR_ERR(consumers[i].consumer);
1891                         consumers[i].consumer = NULL;
1892                         goto err;
1893                 }
1894         }
1895
1896         return 0;
1897
1898 err:
1899         for (i = 0; i < num_consumers && consumers[i].consumer; i++)
1900                 regulator_put(consumers[i].consumer);
1901
1902         return ret;
1903 }
1904 EXPORT_SYMBOL_GPL(regulator_bulk_get);
1905
1906 /**
1907  * regulator_bulk_enable - enable multiple regulator consumers
1908  *
1909  * @num_consumers: Number of consumers
1910  * @consumers:     Consumer data; clients are stored here.
1911  * @return         0 on success, an errno on failure
1912  *
1913  * This convenience API allows consumers to enable multiple regulator
1914  * clients in a single API call.  If any consumers cannot be enabled
1915  * then any others that were enabled will be disabled again prior to
1916  * return.
1917  */
1918 int regulator_bulk_enable(int num_consumers,
1919                           struct regulator_bulk_data *consumers)
1920 {
1921         int i;
1922         int ret;
1923
1924         for (i = 0; i < num_consumers; i++) {
1925                 ret = regulator_enable(consumers[i].consumer);
1926                 if (ret != 0)
1927                         goto err;
1928         }
1929
1930         return 0;
1931
1932 err:
1933         printk(KERN_ERR "Failed to enable %s\n", consumers[i].supply);
1934         for (i = 0; i < num_consumers; i++)
1935                 regulator_disable(consumers[i].consumer);
1936
1937         return ret;
1938 }
1939 EXPORT_SYMBOL_GPL(regulator_bulk_enable);
1940
1941 /**
1942  * regulator_bulk_disable - disable multiple regulator consumers
1943  *
1944  * @num_consumers: Number of consumers
1945  * @consumers:     Consumer data; clients are stored here.
1946  * @return         0 on success, an errno on failure
1947  *
1948  * This convenience API allows consumers to disable multiple regulator
1949  * clients in a single API call.  If any consumers cannot be enabled
1950  * then any others that were disabled will be disabled again prior to
1951  * return.
1952  */
1953 int regulator_bulk_disable(int num_consumers,
1954                            struct regulator_bulk_data *consumers)
1955 {
1956         int i;
1957         int ret;
1958
1959         for (i = 0; i < num_consumers; i++) {
1960                 ret = regulator_disable(consumers[i].consumer);
1961                 if (ret != 0)
1962                         goto err;
1963         }
1964
1965         return 0;
1966
1967 err:
1968         printk(KERN_ERR "Failed to disable %s\n", consumers[i].supply);
1969         for (i = 0; i < num_consumers; i++)
1970                 regulator_enable(consumers[i].consumer);
1971
1972         return ret;
1973 }
1974 EXPORT_SYMBOL_GPL(regulator_bulk_disable);
1975
1976 /**
1977  * regulator_bulk_free - free multiple regulator consumers
1978  *
1979  * @num_consumers: Number of consumers
1980  * @consumers:     Consumer data; clients are stored here.
1981  *
1982  * This convenience API allows consumers to free multiple regulator
1983  * clients in a single API call.
1984  */
1985 void regulator_bulk_free(int num_consumers,
1986                          struct regulator_bulk_data *consumers)
1987 {
1988         int i;
1989
1990         for (i = 0; i < num_consumers; i++) {
1991                 regulator_put(consumers[i].consumer);
1992                 consumers[i].consumer = NULL;
1993         }
1994 }
1995 EXPORT_SYMBOL_GPL(regulator_bulk_free);
1996
1997 /**
1998  * regulator_notifier_call_chain - call regulator event notifier
1999  * @rdev: regulator source
2000  * @event: notifier block
2001  * @data: callback-specific data.
2002  *
2003  * Called by regulator drivers to notify clients a regulator event has
2004  * occurred. We also notify regulator clients downstream.
2005  * Note lock must be held by caller.
2006  */
2007 int regulator_notifier_call_chain(struct regulator_dev *rdev,
2008                                   unsigned long event, void *data)
2009 {
2010         _notifier_call_chain(rdev, event, data);
2011         return NOTIFY_DONE;
2012
2013 }
2014 EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
2015
2016 /**
2017  * regulator_mode_to_status - convert a regulator mode into a status
2018  *
2019  * @mode: Mode to convert
2020  *
2021  * Convert a regulator mode into a status.
2022  */
2023 int regulator_mode_to_status(unsigned int mode)
2024 {
2025         switch (mode) {
2026         case REGULATOR_MODE_FAST:
2027                 return REGULATOR_STATUS_FAST;
2028         case REGULATOR_MODE_NORMAL:
2029                 return REGULATOR_STATUS_NORMAL;
2030         case REGULATOR_MODE_IDLE:
2031                 return REGULATOR_STATUS_IDLE;
2032         case REGULATOR_STATUS_STANDBY:
2033                 return REGULATOR_STATUS_STANDBY;
2034         default:
2035                 return 0;
2036         }
2037 }
2038 EXPORT_SYMBOL_GPL(regulator_mode_to_status);
2039
2040 /*
2041  * To avoid cluttering sysfs (and memory) with useless state, only
2042  * create attributes that can be meaningfully displayed.
2043  */
2044 static int add_regulator_attributes(struct regulator_dev *rdev)
2045 {
2046         struct device           *dev = &rdev->dev;
2047         struct regulator_ops    *ops = rdev->desc->ops;
2048         int                     status = 0;
2049
2050         /* some attributes need specific methods to be displayed */
2051         if (ops->get_voltage) {
2052                 status = device_create_file(dev, &dev_attr_microvolts);
2053                 if (status < 0)
2054                         return status;
2055         }
2056         if (ops->get_current_limit) {
2057                 status = device_create_file(dev, &dev_attr_microamps);
2058                 if (status < 0)
2059                         return status;
2060         }
2061         if (ops->get_mode) {
2062                 status = device_create_file(dev, &dev_attr_opmode);
2063                 if (status < 0)
2064                         return status;
2065         }
2066         if (ops->is_enabled) {
2067                 status = device_create_file(dev, &dev_attr_state);
2068                 if (status < 0)
2069                         return status;
2070         }
2071         if (ops->get_status) {
2072                 status = device_create_file(dev, &dev_attr_status);
2073                 if (status < 0)
2074                         return status;
2075         }
2076
2077         /* some attributes are type-specific */
2078         if (rdev->desc->type == REGULATOR_CURRENT) {
2079                 status = device_create_file(dev, &dev_attr_requested_microamps);
2080                 if (status < 0)
2081                         return status;
2082         }
2083
2084         /* all the other attributes exist to support constraints;
2085          * don't show them if there are no constraints, or if the
2086          * relevant supporting methods are missing.
2087          */
2088         if (!rdev->constraints)
2089                 return status;
2090
2091         /* constraints need specific supporting methods */
2092         if (ops->set_voltage) {
2093                 status = device_create_file(dev, &dev_attr_min_microvolts);
2094                 if (status < 0)
2095                         return status;
2096                 status = device_create_file(dev, &dev_attr_max_microvolts);
2097                 if (status < 0)
2098                         return status;
2099         }
2100         if (ops->set_current_limit) {
2101                 status = device_create_file(dev, &dev_attr_min_microamps);
2102                 if (status < 0)
2103                         return status;
2104                 status = device_create_file(dev, &dev_attr_max_microamps);
2105                 if (status < 0)
2106                         return status;
2107         }
2108
2109         /* suspend mode constraints need multiple supporting methods */
2110         if (!(ops->set_suspend_enable && ops->set_suspend_disable))
2111                 return status;
2112
2113         status = device_create_file(dev, &dev_attr_suspend_standby_state);
2114         if (status < 0)
2115                 return status;
2116         status = device_create_file(dev, &dev_attr_suspend_mem_state);
2117         if (status < 0)
2118                 return status;
2119         status = device_create_file(dev, &dev_attr_suspend_disk_state);
2120         if (status < 0)
2121                 return status;
2122
2123         if (ops->set_suspend_voltage) {
2124                 status = device_create_file(dev,
2125                                 &dev_attr_suspend_standby_microvolts);
2126                 if (status < 0)
2127                         return status;
2128                 status = device_create_file(dev,
2129                                 &dev_attr_suspend_mem_microvolts);
2130                 if (status < 0)
2131                         return status;
2132                 status = device_create_file(dev,
2133                                 &dev_attr_suspend_disk_microvolts);
2134                 if (status < 0)
2135                         return status;
2136         }
2137
2138         if (ops->set_suspend_mode) {
2139                 status = device_create_file(dev,
2140                                 &dev_attr_suspend_standby_mode);
2141                 if (status < 0)
2142                         return status;
2143                 status = device_create_file(dev,
2144                                 &dev_attr_suspend_mem_mode);
2145                 if (status < 0)
2146                         return status;
2147                 status = device_create_file(dev,
2148                                 &dev_attr_suspend_disk_mode);
2149                 if (status < 0)
2150                         return status;
2151         }
2152
2153         return status;
2154 }
2155
2156 /**
2157  * regulator_register - register regulator
2158  * @regulator_desc: regulator to register
2159  * @dev: struct device for the regulator
2160  * @init_data: platform provided init data, passed through by driver
2161  * @driver_data: private regulator data
2162  *
2163  * Called by regulator drivers to register a regulator.
2164  * Returns 0 on success.
2165  */
2166 struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc,
2167         struct device *dev, struct regulator_init_data *init_data,
2168         void *driver_data)
2169 {
2170         static atomic_t regulator_no = ATOMIC_INIT(0);
2171         struct regulator_dev *rdev;
2172         int ret, i;
2173
2174         if (regulator_desc == NULL)
2175                 return ERR_PTR(-EINVAL);
2176
2177         if (regulator_desc->name == NULL || regulator_desc->ops == NULL)
2178                 return ERR_PTR(-EINVAL);
2179
2180         if (regulator_desc->type != REGULATOR_VOLTAGE &&
2181             regulator_desc->type != REGULATOR_CURRENT)
2182                 return ERR_PTR(-EINVAL);
2183
2184         if (!init_data)
2185                 return ERR_PTR(-EINVAL);
2186
2187         rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
2188         if (rdev == NULL)
2189                 return ERR_PTR(-ENOMEM);
2190
2191         mutex_lock(&regulator_list_mutex);
2192
2193         mutex_init(&rdev->mutex);
2194         rdev->reg_data = driver_data;
2195         rdev->owner = regulator_desc->owner;
2196         rdev->desc = regulator_desc;
2197         INIT_LIST_HEAD(&rdev->consumer_list);
2198         INIT_LIST_HEAD(&rdev->supply_list);
2199         INIT_LIST_HEAD(&rdev->list);
2200         INIT_LIST_HEAD(&rdev->slist);
2201         BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
2202
2203         /* preform any regulator specific init */
2204         if (init_data->regulator_init) {
2205                 ret = init_data->regulator_init(rdev->reg_data);
2206                 if (ret < 0)
2207                         goto clean;
2208         }
2209
2210         /* register with sysfs */
2211         rdev->dev.class = &regulator_class;
2212         rdev->dev.parent = dev;
2213         dev_set_name(&rdev->dev, "regulator.%d",
2214                      atomic_inc_return(&regulator_no) - 1);
2215         ret = device_register(&rdev->dev);
2216         if (ret != 0)
2217                 goto clean;
2218
2219         dev_set_drvdata(&rdev->dev, rdev);
2220
2221         /* set regulator constraints */
2222         ret = set_machine_constraints(rdev, &init_data->constraints);
2223         if (ret < 0)
2224                 goto scrub;
2225
2226         /* add attributes supported by this regulator */
2227         ret = add_regulator_attributes(rdev);
2228         if (ret < 0)
2229                 goto scrub;
2230
2231         /* set supply regulator if it exists */
2232         if (init_data->supply_regulator_dev) {
2233                 ret = set_supply(rdev,
2234                         dev_get_drvdata(init_data->supply_regulator_dev));
2235                 if (ret < 0)
2236                         goto scrub;
2237         }
2238
2239         /* add consumers devices */
2240         for (i = 0; i < init_data->num_consumer_supplies; i++) {
2241                 ret = set_consumer_device_supply(rdev,
2242                         init_data->consumer_supplies[i].dev,
2243                         init_data->consumer_supplies[i].dev_name,
2244                         init_data->consumer_supplies[i].supply);
2245                 if (ret < 0) {
2246                         for (--i; i >= 0; i--)
2247                                 unset_consumer_device_supply(rdev,
2248                                     init_data->consumer_supplies[i].dev_name,
2249                                     init_data->consumer_supplies[i].dev);
2250                         goto scrub;
2251                 }
2252         }
2253
2254         list_add(&rdev->list, &regulator_list);
2255 out:
2256         mutex_unlock(&regulator_list_mutex);
2257         return rdev;
2258
2259 scrub:
2260         device_unregister(&rdev->dev);
2261         /* device core frees rdev */
2262         rdev = ERR_PTR(ret);
2263         goto out;
2264
2265 clean:
2266         kfree(rdev);
2267         rdev = ERR_PTR(ret);
2268         goto out;
2269 }
2270 EXPORT_SYMBOL_GPL(regulator_register);
2271
2272 /**
2273  * regulator_unregister - unregister regulator
2274  * @rdev: regulator to unregister
2275  *
2276  * Called by regulator drivers to unregister a regulator.
2277  */
2278 void regulator_unregister(struct regulator_dev *rdev)
2279 {
2280         if (rdev == NULL)
2281                 return;
2282
2283         mutex_lock(&regulator_list_mutex);
2284         WARN_ON(rdev->open_count);
2285         unset_regulator_supplies(rdev);
2286         list_del(&rdev->list);
2287         if (rdev->supply)
2288                 sysfs_remove_link(&rdev->dev.kobj, "supply");
2289         device_unregister(&rdev->dev);
2290         mutex_unlock(&regulator_list_mutex);
2291 }
2292 EXPORT_SYMBOL_GPL(regulator_unregister);
2293
2294 /**
2295  * regulator_suspend_prepare - prepare regulators for system wide suspend
2296  * @state: system suspend state
2297  *
2298  * Configure each regulator with it's suspend operating parameters for state.
2299  * This will usually be called by machine suspend code prior to supending.
2300  */
2301 int regulator_suspend_prepare(suspend_state_t state)
2302 {
2303         struct regulator_dev *rdev;
2304         int ret = 0;
2305
2306         /* ON is handled by regulator active state */
2307         if (state == PM_SUSPEND_ON)
2308                 return -EINVAL;
2309
2310         mutex_lock(&regulator_list_mutex);
2311         list_for_each_entry(rdev, &regulator_list, list) {
2312
2313                 mutex_lock(&rdev->mutex);
2314                 ret = suspend_prepare(rdev, state);
2315                 mutex_unlock(&rdev->mutex);
2316
2317                 if (ret < 0) {
2318                         printk(KERN_ERR "%s: failed to prepare %s\n",
2319                                 __func__, rdev->desc->name);
2320                         goto out;
2321                 }
2322         }
2323 out:
2324         mutex_unlock(&regulator_list_mutex);
2325         return ret;
2326 }
2327 EXPORT_SYMBOL_GPL(regulator_suspend_prepare);
2328
2329 /**
2330  * regulator_has_full_constraints - the system has fully specified constraints
2331  *
2332  * Calling this function will cause the regulator API to disable all
2333  * regulators which have a zero use count and don't have an always_on
2334  * constraint in a late_initcall.
2335  *
2336  * The intention is that this will become the default behaviour in a
2337  * future kernel release so users are encouraged to use this facility
2338  * now.
2339  */
2340 void regulator_has_full_constraints(void)
2341 {
2342         has_full_constraints = 1;
2343 }
2344 EXPORT_SYMBOL_GPL(regulator_has_full_constraints);
2345
2346 /**
2347  * rdev_get_drvdata - get rdev regulator driver data
2348  * @rdev: regulator
2349  *
2350  * Get rdev regulator driver private data. This call can be used in the
2351  * regulator driver context.
2352  */
2353 void *rdev_get_drvdata(struct regulator_dev *rdev)
2354 {
2355         return rdev->reg_data;
2356 }
2357 EXPORT_SYMBOL_GPL(rdev_get_drvdata);
2358
2359 /**
2360  * regulator_get_drvdata - get regulator driver data
2361  * @regulator: regulator
2362  *
2363  * Get regulator driver private data. This call can be used in the consumer
2364  * driver context when non API regulator specific functions need to be called.
2365  */
2366 void *regulator_get_drvdata(struct regulator *regulator)
2367 {
2368         return regulator->rdev->reg_data;
2369 }
2370 EXPORT_SYMBOL_GPL(regulator_get_drvdata);
2371
2372 /**
2373  * regulator_set_drvdata - set regulator driver data
2374  * @regulator: regulator
2375  * @data: data
2376  */
2377 void regulator_set_drvdata(struct regulator *regulator, void *data)
2378 {
2379         regulator->rdev->reg_data = data;
2380 }
2381 EXPORT_SYMBOL_GPL(regulator_set_drvdata);
2382
2383 /**
2384  * regulator_get_id - get regulator ID
2385  * @rdev: regulator
2386  */
2387 int rdev_get_id(struct regulator_dev *rdev)
2388 {
2389         return rdev->desc->id;
2390 }
2391 EXPORT_SYMBOL_GPL(rdev_get_id);
2392
2393 struct device *rdev_get_dev(struct regulator_dev *rdev)
2394 {
2395         return &rdev->dev;
2396 }
2397 EXPORT_SYMBOL_GPL(rdev_get_dev);
2398
2399 void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
2400 {
2401         return reg_init_data->driver_data;
2402 }
2403 EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
2404
2405 static int __init regulator_init(void)
2406 {
2407         printk(KERN_INFO "regulator: core version %s\n", REGULATOR_VERSION);
2408         return class_register(&regulator_class);
2409 }
2410
2411 /* init early to allow our consumers to complete system booting */
2412 core_initcall(regulator_init);
2413
2414 static int __init regulator_init_complete(void)
2415 {
2416         struct regulator_dev *rdev;
2417         struct regulator_ops *ops;
2418         struct regulation_constraints *c;
2419         int enabled, ret;
2420         const char *name;
2421
2422         mutex_lock(&regulator_list_mutex);
2423
2424         /* If we have a full configuration then disable any regulators
2425          * which are not in use or always_on.  This will become the
2426          * default behaviour in the future.
2427          */
2428         list_for_each_entry(rdev, &regulator_list, list) {
2429                 ops = rdev->desc->ops;
2430                 c = rdev->constraints;
2431
2432                 if (c && c->name)
2433                         name = c->name;
2434                 else if (rdev->desc->name)
2435                         name = rdev->desc->name;
2436                 else
2437                         name = "regulator";
2438
2439                 if (!ops->disable || (c && c->always_on))
2440                         continue;
2441
2442                 mutex_lock(&rdev->mutex);
2443
2444                 if (rdev->use_count)
2445                         goto unlock;
2446
2447                 /* If we can't read the status assume it's on. */
2448                 if (ops->is_enabled)
2449                         enabled = ops->is_enabled(rdev);
2450                 else
2451                         enabled = 1;
2452
2453                 if (!enabled)
2454                         goto unlock;
2455
2456                 if (has_full_constraints) {
2457                         /* We log since this may kill the system if it
2458                          * goes wrong. */
2459                         printk(KERN_INFO "%s: disabling %s\n",
2460                                __func__, name);
2461                         ret = ops->disable(rdev);
2462                         if (ret != 0) {
2463                                 printk(KERN_ERR
2464                                        "%s: couldn't disable %s: %d\n",
2465                                        __func__, name, ret);
2466                         }
2467                 } else {
2468                         /* The intention is that in future we will
2469                          * assume that full constraints are provided
2470                          * so warn even if we aren't going to do
2471                          * anything here.
2472                          */
2473                         printk(KERN_WARNING
2474                                "%s: incomplete constraints, leaving %s on\n",
2475                                __func__, name);
2476                 }
2477
2478 unlock:
2479                 mutex_unlock(&rdev->mutex);
2480         }
2481
2482         mutex_unlock(&regulator_list_mutex);
2483
2484         return 0;
2485 }
2486 late_initcall(regulator_init_complete);