regulator: Include the device name in the microamps_requested_ file
[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 #define pr_fmt(fmt) "%s: " fmt, __func__
17
18 #include <linux/kernel.h>
19 #include <linux/init.h>
20 #include <linux/debugfs.h>
21 #include <linux/device.h>
22 #include <linux/slab.h>
23 #include <linux/async.h>
24 #include <linux/err.h>
25 #include <linux/mutex.h>
26 #include <linux/suspend.h>
27 #include <linux/delay.h>
28 #include <linux/regulator/consumer.h>
29 #include <linux/regulator/driver.h>
30 #include <linux/regulator/machine.h>
31
32 #define CREATE_TRACE_POINTS
33 #include <trace/events/regulator.h>
34
35 #include "dummy.h"
36
37 #define rdev_err(rdev, fmt, ...)                                        \
38         pr_err("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
39 #define rdev_warn(rdev, fmt, ...)                                       \
40         pr_warn("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
41 #define rdev_info(rdev, fmt, ...)                                       \
42         pr_info("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
43 #define rdev_dbg(rdev, fmt, ...)                                        \
44         pr_debug("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
45
46 static DEFINE_MUTEX(regulator_list_mutex);
47 static LIST_HEAD(regulator_list);
48 static LIST_HEAD(regulator_map_list);
49 static bool has_full_constraints;
50 static bool board_wants_dummy_regulator;
51
52 #ifdef CONFIG_DEBUG_FS
53 static struct dentry *debugfs_root;
54 #endif
55
56 /*
57  * struct regulator_map
58  *
59  * Used to provide symbolic supply names to devices.
60  */
61 struct regulator_map {
62         struct list_head list;
63         const char *dev_name;   /* The dev_name() for the consumer */
64         const char *supply;
65         struct regulator_dev *regulator;
66 };
67
68 /*
69  * struct regulator
70  *
71  * One for each consumer device.
72  */
73 struct regulator {
74         struct device *dev;
75         struct list_head list;
76         int uA_load;
77         int min_uV;
78         int max_uV;
79         char *supply_name;
80         struct device_attribute dev_attr;
81         struct regulator_dev *rdev;
82 };
83
84 static int _regulator_is_enabled(struct regulator_dev *rdev);
85 static int _regulator_disable(struct regulator_dev *rdev,
86                 struct regulator_dev **supply_rdev_ptr);
87 static int _regulator_get_voltage(struct regulator_dev *rdev);
88 static int _regulator_get_current_limit(struct regulator_dev *rdev);
89 static unsigned int _regulator_get_mode(struct regulator_dev *rdev);
90 static void _notifier_call_chain(struct regulator_dev *rdev,
91                                   unsigned long event, void *data);
92 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
93                                      int min_uV, int max_uV);
94
95 static const char *rdev_get_name(struct regulator_dev *rdev)
96 {
97         if (rdev->constraints && rdev->constraints->name)
98                 return rdev->constraints->name;
99         else if (rdev->desc->name)
100                 return rdev->desc->name;
101         else
102                 return "";
103 }
104
105 /* gets the regulator for a given consumer device */
106 static struct regulator *get_device_regulator(struct device *dev)
107 {
108         struct regulator *regulator = NULL;
109         struct regulator_dev *rdev;
110
111         mutex_lock(&regulator_list_mutex);
112         list_for_each_entry(rdev, &regulator_list, list) {
113                 mutex_lock(&rdev->mutex);
114                 list_for_each_entry(regulator, &rdev->consumer_list, list) {
115                         if (regulator->dev == dev) {
116                                 mutex_unlock(&rdev->mutex);
117                                 mutex_unlock(&regulator_list_mutex);
118                                 return regulator;
119                         }
120                 }
121                 mutex_unlock(&rdev->mutex);
122         }
123         mutex_unlock(&regulator_list_mutex);
124         return NULL;
125 }
126
127 /* Platform voltage constraint check */
128 static int regulator_check_voltage(struct regulator_dev *rdev,
129                                    int *min_uV, int *max_uV)
130 {
131         BUG_ON(*min_uV > *max_uV);
132
133         if (!rdev->constraints) {
134                 rdev_err(rdev, "no constraints\n");
135                 return -ENODEV;
136         }
137         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
138                 rdev_err(rdev, "operation not allowed\n");
139                 return -EPERM;
140         }
141
142         if (*max_uV > rdev->constraints->max_uV)
143                 *max_uV = rdev->constraints->max_uV;
144         if (*min_uV < rdev->constraints->min_uV)
145                 *min_uV = rdev->constraints->min_uV;
146
147         if (*min_uV > *max_uV)
148                 return -EINVAL;
149
150         return 0;
151 }
152
153 /* Make sure we select a voltage that suits the needs of all
154  * regulator consumers
155  */
156 static int regulator_check_consumers(struct regulator_dev *rdev,
157                                      int *min_uV, int *max_uV)
158 {
159         struct regulator *regulator;
160
161         list_for_each_entry(regulator, &rdev->consumer_list, list) {
162                 /*
163                  * Assume consumers that didn't say anything are OK
164                  * with anything in the constraint range.
165                  */
166                 if (!regulator->min_uV && !regulator->max_uV)
167                         continue;
168
169                 if (*max_uV > regulator->max_uV)
170                         *max_uV = regulator->max_uV;
171                 if (*min_uV < regulator->min_uV)
172                         *min_uV = regulator->min_uV;
173         }
174
175         if (*min_uV > *max_uV)
176                 return -EINVAL;
177
178         return 0;
179 }
180
181 /* current constraint check */
182 static int regulator_check_current_limit(struct regulator_dev *rdev,
183                                         int *min_uA, int *max_uA)
184 {
185         BUG_ON(*min_uA > *max_uA);
186
187         if (!rdev->constraints) {
188                 rdev_err(rdev, "no constraints\n");
189                 return -ENODEV;
190         }
191         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_CURRENT)) {
192                 rdev_err(rdev, "operation not allowed\n");
193                 return -EPERM;
194         }
195
196         if (*max_uA > rdev->constraints->max_uA)
197                 *max_uA = rdev->constraints->max_uA;
198         if (*min_uA < rdev->constraints->min_uA)
199                 *min_uA = rdev->constraints->min_uA;
200
201         if (*min_uA > *max_uA)
202                 return -EINVAL;
203
204         return 0;
205 }
206
207 /* operating mode constraint check */
208 static int regulator_mode_constrain(struct regulator_dev *rdev, int *mode)
209 {
210         switch (*mode) {
211         case REGULATOR_MODE_FAST:
212         case REGULATOR_MODE_NORMAL:
213         case REGULATOR_MODE_IDLE:
214         case REGULATOR_MODE_STANDBY:
215                 break;
216         default:
217                 return -EINVAL;
218         }
219
220         if (!rdev->constraints) {
221                 rdev_err(rdev, "no constraints\n");
222                 return -ENODEV;
223         }
224         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_MODE)) {
225                 rdev_err(rdev, "operation not allowed\n");
226                 return -EPERM;
227         }
228
229         /* The modes are bitmasks, the most power hungry modes having
230          * the lowest values. If the requested mode isn't supported
231          * try higher modes. */
232         while (*mode) {
233                 if (rdev->constraints->valid_modes_mask & *mode)
234                         return 0;
235                 *mode /= 2;
236         }
237
238         return -EINVAL;
239 }
240
241 /* dynamic regulator mode switching constraint check */
242 static int regulator_check_drms(struct regulator_dev *rdev)
243 {
244         if (!rdev->constraints) {
245                 rdev_err(rdev, "no constraints\n");
246                 return -ENODEV;
247         }
248         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS)) {
249                 rdev_err(rdev, "operation not allowed\n");
250                 return -EPERM;
251         }
252         return 0;
253 }
254
255 static ssize_t device_requested_uA_show(struct device *dev,
256                              struct device_attribute *attr, char *buf)
257 {
258         struct regulator *regulator;
259
260         regulator = get_device_regulator(dev);
261         if (regulator == NULL)
262                 return 0;
263
264         return sprintf(buf, "%d\n", regulator->uA_load);
265 }
266
267 static ssize_t regulator_uV_show(struct device *dev,
268                                 struct device_attribute *attr, char *buf)
269 {
270         struct regulator_dev *rdev = dev_get_drvdata(dev);
271         ssize_t ret;
272
273         mutex_lock(&rdev->mutex);
274         ret = sprintf(buf, "%d\n", _regulator_get_voltage(rdev));
275         mutex_unlock(&rdev->mutex);
276
277         return ret;
278 }
279 static DEVICE_ATTR(microvolts, 0444, regulator_uV_show, NULL);
280
281 static ssize_t regulator_uA_show(struct device *dev,
282                                 struct device_attribute *attr, char *buf)
283 {
284         struct regulator_dev *rdev = dev_get_drvdata(dev);
285
286         return sprintf(buf, "%d\n", _regulator_get_current_limit(rdev));
287 }
288 static DEVICE_ATTR(microamps, 0444, regulator_uA_show, NULL);
289
290 static ssize_t regulator_name_show(struct device *dev,
291                              struct device_attribute *attr, char *buf)
292 {
293         struct regulator_dev *rdev = dev_get_drvdata(dev);
294
295         return sprintf(buf, "%s\n", rdev_get_name(rdev));
296 }
297
298 static ssize_t regulator_print_opmode(char *buf, int mode)
299 {
300         switch (mode) {
301         case REGULATOR_MODE_FAST:
302                 return sprintf(buf, "fast\n");
303         case REGULATOR_MODE_NORMAL:
304                 return sprintf(buf, "normal\n");
305         case REGULATOR_MODE_IDLE:
306                 return sprintf(buf, "idle\n");
307         case REGULATOR_MODE_STANDBY:
308                 return sprintf(buf, "standby\n");
309         }
310         return sprintf(buf, "unknown\n");
311 }
312
313 static ssize_t regulator_opmode_show(struct device *dev,
314                                     struct device_attribute *attr, char *buf)
315 {
316         struct regulator_dev *rdev = dev_get_drvdata(dev);
317
318         return regulator_print_opmode(buf, _regulator_get_mode(rdev));
319 }
320 static DEVICE_ATTR(opmode, 0444, regulator_opmode_show, NULL);
321
322 static ssize_t regulator_print_state(char *buf, int state)
323 {
324         if (state > 0)
325                 return sprintf(buf, "enabled\n");
326         else if (state == 0)
327                 return sprintf(buf, "disabled\n");
328         else
329                 return sprintf(buf, "unknown\n");
330 }
331
332 static ssize_t regulator_state_show(struct device *dev,
333                                    struct device_attribute *attr, char *buf)
334 {
335         struct regulator_dev *rdev = dev_get_drvdata(dev);
336         ssize_t ret;
337
338         mutex_lock(&rdev->mutex);
339         ret = regulator_print_state(buf, _regulator_is_enabled(rdev));
340         mutex_unlock(&rdev->mutex);
341
342         return ret;
343 }
344 static DEVICE_ATTR(state, 0444, regulator_state_show, NULL);
345
346 static ssize_t regulator_status_show(struct device *dev,
347                                    struct device_attribute *attr, char *buf)
348 {
349         struct regulator_dev *rdev = dev_get_drvdata(dev);
350         int status;
351         char *label;
352
353         status = rdev->desc->ops->get_status(rdev);
354         if (status < 0)
355                 return status;
356
357         switch (status) {
358         case REGULATOR_STATUS_OFF:
359                 label = "off";
360                 break;
361         case REGULATOR_STATUS_ON:
362                 label = "on";
363                 break;
364         case REGULATOR_STATUS_ERROR:
365                 label = "error";
366                 break;
367         case REGULATOR_STATUS_FAST:
368                 label = "fast";
369                 break;
370         case REGULATOR_STATUS_NORMAL:
371                 label = "normal";
372                 break;
373         case REGULATOR_STATUS_IDLE:
374                 label = "idle";
375                 break;
376         case REGULATOR_STATUS_STANDBY:
377                 label = "standby";
378                 break;
379         default:
380                 return -ERANGE;
381         }
382
383         return sprintf(buf, "%s\n", label);
384 }
385 static DEVICE_ATTR(status, 0444, regulator_status_show, NULL);
386
387 static ssize_t regulator_min_uA_show(struct device *dev,
388                                     struct device_attribute *attr, char *buf)
389 {
390         struct regulator_dev *rdev = dev_get_drvdata(dev);
391
392         if (!rdev->constraints)
393                 return sprintf(buf, "constraint not defined\n");
394
395         return sprintf(buf, "%d\n", rdev->constraints->min_uA);
396 }
397 static DEVICE_ATTR(min_microamps, 0444, regulator_min_uA_show, NULL);
398
399 static ssize_t regulator_max_uA_show(struct device *dev,
400                                     struct device_attribute *attr, char *buf)
401 {
402         struct regulator_dev *rdev = dev_get_drvdata(dev);
403
404         if (!rdev->constraints)
405                 return sprintf(buf, "constraint not defined\n");
406
407         return sprintf(buf, "%d\n", rdev->constraints->max_uA);
408 }
409 static DEVICE_ATTR(max_microamps, 0444, regulator_max_uA_show, NULL);
410
411 static ssize_t regulator_min_uV_show(struct device *dev,
412                                     struct device_attribute *attr, char *buf)
413 {
414         struct regulator_dev *rdev = dev_get_drvdata(dev);
415
416         if (!rdev->constraints)
417                 return sprintf(buf, "constraint not defined\n");
418
419         return sprintf(buf, "%d\n", rdev->constraints->min_uV);
420 }
421 static DEVICE_ATTR(min_microvolts, 0444, regulator_min_uV_show, NULL);
422
423 static ssize_t regulator_max_uV_show(struct device *dev,
424                                     struct device_attribute *attr, char *buf)
425 {
426         struct regulator_dev *rdev = dev_get_drvdata(dev);
427
428         if (!rdev->constraints)
429                 return sprintf(buf, "constraint not defined\n");
430
431         return sprintf(buf, "%d\n", rdev->constraints->max_uV);
432 }
433 static DEVICE_ATTR(max_microvolts, 0444, regulator_max_uV_show, NULL);
434
435 static ssize_t regulator_total_uA_show(struct device *dev,
436                                       struct device_attribute *attr, char *buf)
437 {
438         struct regulator_dev *rdev = dev_get_drvdata(dev);
439         struct regulator *regulator;
440         int uA = 0;
441
442         mutex_lock(&rdev->mutex);
443         list_for_each_entry(regulator, &rdev->consumer_list, list)
444                 uA += regulator->uA_load;
445         mutex_unlock(&rdev->mutex);
446         return sprintf(buf, "%d\n", uA);
447 }
448 static DEVICE_ATTR(requested_microamps, 0444, regulator_total_uA_show, NULL);
449
450 static ssize_t regulator_num_users_show(struct device *dev,
451                                       struct device_attribute *attr, char *buf)
452 {
453         struct regulator_dev *rdev = dev_get_drvdata(dev);
454         return sprintf(buf, "%d\n", rdev->use_count);
455 }
456
457 static ssize_t regulator_type_show(struct device *dev,
458                                   struct device_attribute *attr, char *buf)
459 {
460         struct regulator_dev *rdev = dev_get_drvdata(dev);
461
462         switch (rdev->desc->type) {
463         case REGULATOR_VOLTAGE:
464                 return sprintf(buf, "voltage\n");
465         case REGULATOR_CURRENT:
466                 return sprintf(buf, "current\n");
467         }
468         return sprintf(buf, "unknown\n");
469 }
470
471 static ssize_t regulator_suspend_mem_uV_show(struct device *dev,
472                                 struct device_attribute *attr, char *buf)
473 {
474         struct regulator_dev *rdev = dev_get_drvdata(dev);
475
476         return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
477 }
478 static DEVICE_ATTR(suspend_mem_microvolts, 0444,
479                 regulator_suspend_mem_uV_show, NULL);
480
481 static ssize_t regulator_suspend_disk_uV_show(struct device *dev,
482                                 struct device_attribute *attr, char *buf)
483 {
484         struct regulator_dev *rdev = dev_get_drvdata(dev);
485
486         return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
487 }
488 static DEVICE_ATTR(suspend_disk_microvolts, 0444,
489                 regulator_suspend_disk_uV_show, NULL);
490
491 static ssize_t regulator_suspend_standby_uV_show(struct device *dev,
492                                 struct device_attribute *attr, char *buf)
493 {
494         struct regulator_dev *rdev = dev_get_drvdata(dev);
495
496         return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
497 }
498 static DEVICE_ATTR(suspend_standby_microvolts, 0444,
499                 regulator_suspend_standby_uV_show, NULL);
500
501 static ssize_t regulator_suspend_mem_mode_show(struct device *dev,
502                                 struct device_attribute *attr, char *buf)
503 {
504         struct regulator_dev *rdev = dev_get_drvdata(dev);
505
506         return regulator_print_opmode(buf,
507                 rdev->constraints->state_mem.mode);
508 }
509 static DEVICE_ATTR(suspend_mem_mode, 0444,
510                 regulator_suspend_mem_mode_show, NULL);
511
512 static ssize_t regulator_suspend_disk_mode_show(struct device *dev,
513                                 struct device_attribute *attr, char *buf)
514 {
515         struct regulator_dev *rdev = dev_get_drvdata(dev);
516
517         return regulator_print_opmode(buf,
518                 rdev->constraints->state_disk.mode);
519 }
520 static DEVICE_ATTR(suspend_disk_mode, 0444,
521                 regulator_suspend_disk_mode_show, NULL);
522
523 static ssize_t regulator_suspend_standby_mode_show(struct device *dev,
524                                 struct device_attribute *attr, char *buf)
525 {
526         struct regulator_dev *rdev = dev_get_drvdata(dev);
527
528         return regulator_print_opmode(buf,
529                 rdev->constraints->state_standby.mode);
530 }
531 static DEVICE_ATTR(suspend_standby_mode, 0444,
532                 regulator_suspend_standby_mode_show, NULL);
533
534 static ssize_t regulator_suspend_mem_state_show(struct device *dev,
535                                    struct device_attribute *attr, char *buf)
536 {
537         struct regulator_dev *rdev = dev_get_drvdata(dev);
538
539         return regulator_print_state(buf,
540                         rdev->constraints->state_mem.enabled);
541 }
542 static DEVICE_ATTR(suspend_mem_state, 0444,
543                 regulator_suspend_mem_state_show, NULL);
544
545 static ssize_t regulator_suspend_disk_state_show(struct device *dev,
546                                    struct device_attribute *attr, char *buf)
547 {
548         struct regulator_dev *rdev = dev_get_drvdata(dev);
549
550         return regulator_print_state(buf,
551                         rdev->constraints->state_disk.enabled);
552 }
553 static DEVICE_ATTR(suspend_disk_state, 0444,
554                 regulator_suspend_disk_state_show, NULL);
555
556 static ssize_t regulator_suspend_standby_state_show(struct device *dev,
557                                    struct device_attribute *attr, char *buf)
558 {
559         struct regulator_dev *rdev = dev_get_drvdata(dev);
560
561         return regulator_print_state(buf,
562                         rdev->constraints->state_standby.enabled);
563 }
564 static DEVICE_ATTR(suspend_standby_state, 0444,
565                 regulator_suspend_standby_state_show, NULL);
566
567
568 /*
569  * These are the only attributes are present for all regulators.
570  * Other attributes are a function of regulator functionality.
571  */
572 static struct device_attribute regulator_dev_attrs[] = {
573         __ATTR(name, 0444, regulator_name_show, NULL),
574         __ATTR(num_users, 0444, regulator_num_users_show, NULL),
575         __ATTR(type, 0444, regulator_type_show, NULL),
576         __ATTR_NULL,
577 };
578
579 static void regulator_dev_release(struct device *dev)
580 {
581         struct regulator_dev *rdev = dev_get_drvdata(dev);
582         kfree(rdev);
583 }
584
585 static struct class regulator_class = {
586         .name = "regulator",
587         .dev_release = regulator_dev_release,
588         .dev_attrs = regulator_dev_attrs,
589 };
590
591 /* Calculate the new optimum regulator operating mode based on the new total
592  * consumer load. All locks held by caller */
593 static void drms_uA_update(struct regulator_dev *rdev)
594 {
595         struct regulator *sibling;
596         int current_uA = 0, output_uV, input_uV, err;
597         unsigned int mode;
598
599         err = regulator_check_drms(rdev);
600         if (err < 0 || !rdev->desc->ops->get_optimum_mode ||
601             (!rdev->desc->ops->get_voltage &&
602              !rdev->desc->ops->get_voltage_sel) ||
603             !rdev->desc->ops->set_mode)
604                 return;
605
606         /* get output voltage */
607         output_uV = _regulator_get_voltage(rdev);
608         if (output_uV <= 0)
609                 return;
610
611         /* get input voltage */
612         input_uV = 0;
613         if (rdev->supply)
614                 input_uV = _regulator_get_voltage(rdev);
615         if (input_uV <= 0)
616                 input_uV = rdev->constraints->input_uV;
617         if (input_uV <= 0)
618                 return;
619
620         /* calc total requested load */
621         list_for_each_entry(sibling, &rdev->consumer_list, list)
622                 current_uA += sibling->uA_load;
623
624         /* now get the optimum mode for our new total regulator load */
625         mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
626                                                   output_uV, current_uA);
627
628         /* check the new mode is allowed */
629         err = regulator_mode_constrain(rdev, &mode);
630         if (err == 0)
631                 rdev->desc->ops->set_mode(rdev, mode);
632 }
633
634 static int suspend_set_state(struct regulator_dev *rdev,
635         struct regulator_state *rstate)
636 {
637         int ret = 0;
638         bool can_set_state;
639
640         can_set_state = rdev->desc->ops->set_suspend_enable &&
641                 rdev->desc->ops->set_suspend_disable;
642
643         /* If we have no suspend mode configration don't set anything;
644          * only warn if the driver actually makes the suspend mode
645          * configurable.
646          */
647         if (!rstate->enabled && !rstate->disabled) {
648                 if (can_set_state)
649                         rdev_warn(rdev, "No configuration\n");
650                 return 0;
651         }
652
653         if (rstate->enabled && rstate->disabled) {
654                 rdev_err(rdev, "invalid configuration\n");
655                 return -EINVAL;
656         }
657
658         if (!can_set_state) {
659                 rdev_err(rdev, "no way to set suspend state\n");
660                 return -EINVAL;
661         }
662
663         if (rstate->enabled)
664                 ret = rdev->desc->ops->set_suspend_enable(rdev);
665         else
666                 ret = rdev->desc->ops->set_suspend_disable(rdev);
667         if (ret < 0) {
668                 rdev_err(rdev, "failed to enabled/disable\n");
669                 return ret;
670         }
671
672         if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
673                 ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
674                 if (ret < 0) {
675                         rdev_err(rdev, "failed to set voltage\n");
676                         return ret;
677                 }
678         }
679
680         if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
681                 ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
682                 if (ret < 0) {
683                         rdev_err(rdev, "failed to set mode\n");
684                         return ret;
685                 }
686         }
687         return ret;
688 }
689
690 /* locks held by caller */
691 static int suspend_prepare(struct regulator_dev *rdev, suspend_state_t state)
692 {
693         if (!rdev->constraints)
694                 return -EINVAL;
695
696         switch (state) {
697         case PM_SUSPEND_STANDBY:
698                 return suspend_set_state(rdev,
699                         &rdev->constraints->state_standby);
700         case PM_SUSPEND_MEM:
701                 return suspend_set_state(rdev,
702                         &rdev->constraints->state_mem);
703         case PM_SUSPEND_MAX:
704                 return suspend_set_state(rdev,
705                         &rdev->constraints->state_disk);
706         default:
707                 return -EINVAL;
708         }
709 }
710
711 static void print_constraints(struct regulator_dev *rdev)
712 {
713         struct regulation_constraints *constraints = rdev->constraints;
714         char buf[80] = "";
715         int count = 0;
716         int ret;
717
718         if (constraints->min_uV && constraints->max_uV) {
719                 if (constraints->min_uV == constraints->max_uV)
720                         count += sprintf(buf + count, "%d mV ",
721                                          constraints->min_uV / 1000);
722                 else
723                         count += sprintf(buf + count, "%d <--> %d mV ",
724                                          constraints->min_uV / 1000,
725                                          constraints->max_uV / 1000);
726         }
727
728         if (!constraints->min_uV ||
729             constraints->min_uV != constraints->max_uV) {
730                 ret = _regulator_get_voltage(rdev);
731                 if (ret > 0)
732                         count += sprintf(buf + count, "at %d mV ", ret / 1000);
733         }
734
735         if (constraints->uV_offset)
736                 count += sprintf(buf, "%dmV offset ",
737                                  constraints->uV_offset / 1000);
738
739         if (constraints->min_uA && constraints->max_uA) {
740                 if (constraints->min_uA == constraints->max_uA)
741                         count += sprintf(buf + count, "%d mA ",
742                                          constraints->min_uA / 1000);
743                 else
744                         count += sprintf(buf + count, "%d <--> %d mA ",
745                                          constraints->min_uA / 1000,
746                                          constraints->max_uA / 1000);
747         }
748
749         if (!constraints->min_uA ||
750             constraints->min_uA != constraints->max_uA) {
751                 ret = _regulator_get_current_limit(rdev);
752                 if (ret > 0)
753                         count += sprintf(buf + count, "at %d mA ", ret / 1000);
754         }
755
756         if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
757                 count += sprintf(buf + count, "fast ");
758         if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
759                 count += sprintf(buf + count, "normal ");
760         if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
761                 count += sprintf(buf + count, "idle ");
762         if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
763                 count += sprintf(buf + count, "standby");
764
765         rdev_info(rdev, "%s\n", buf);
766 }
767
768 static int machine_constraints_voltage(struct regulator_dev *rdev,
769         struct regulation_constraints *constraints)
770 {
771         struct regulator_ops *ops = rdev->desc->ops;
772         int ret;
773
774         /* do we need to apply the constraint voltage */
775         if (rdev->constraints->apply_uV &&
776             rdev->constraints->min_uV == rdev->constraints->max_uV) {
777                 ret = _regulator_do_set_voltage(rdev,
778                                                 rdev->constraints->min_uV,
779                                                 rdev->constraints->max_uV);
780                 if (ret < 0) {
781                         rdev_err(rdev, "failed to apply %duV constraint\n",
782                                  rdev->constraints->min_uV);
783                         rdev->constraints = NULL;
784                         return ret;
785                 }
786         }
787
788         /* constrain machine-level voltage specs to fit
789          * the actual range supported by this regulator.
790          */
791         if (ops->list_voltage && rdev->desc->n_voltages) {
792                 int     count = rdev->desc->n_voltages;
793                 int     i;
794                 int     min_uV = INT_MAX;
795                 int     max_uV = INT_MIN;
796                 int     cmin = constraints->min_uV;
797                 int     cmax = constraints->max_uV;
798
799                 /* it's safe to autoconfigure fixed-voltage supplies
800                    and the constraints are used by list_voltage. */
801                 if (count == 1 && !cmin) {
802                         cmin = 1;
803                         cmax = INT_MAX;
804                         constraints->min_uV = cmin;
805                         constraints->max_uV = cmax;
806                 }
807
808                 /* voltage constraints are optional */
809                 if ((cmin == 0) && (cmax == 0))
810                         return 0;
811
812                 /* else require explicit machine-level constraints */
813                 if (cmin <= 0 || cmax <= 0 || cmax < cmin) {
814                         rdev_err(rdev, "invalid voltage constraints\n");
815                         return -EINVAL;
816                 }
817
818                 /* initial: [cmin..cmax] valid, [min_uV..max_uV] not */
819                 for (i = 0; i < count; i++) {
820                         int     value;
821
822                         value = ops->list_voltage(rdev, i);
823                         if (value <= 0)
824                                 continue;
825
826                         /* maybe adjust [min_uV..max_uV] */
827                         if (value >= cmin && value < min_uV)
828                                 min_uV = value;
829                         if (value <= cmax && value > max_uV)
830                                 max_uV = value;
831                 }
832
833                 /* final: [min_uV..max_uV] valid iff constraints valid */
834                 if (max_uV < min_uV) {
835                         rdev_err(rdev, "unsupportable voltage constraints\n");
836                         return -EINVAL;
837                 }
838
839                 /* use regulator's subset of machine constraints */
840                 if (constraints->min_uV < min_uV) {
841                         rdev_dbg(rdev, "override min_uV, %d -> %d\n",
842                                  constraints->min_uV, min_uV);
843                         constraints->min_uV = min_uV;
844                 }
845                 if (constraints->max_uV > max_uV) {
846                         rdev_dbg(rdev, "override max_uV, %d -> %d\n",
847                                  constraints->max_uV, max_uV);
848                         constraints->max_uV = max_uV;
849                 }
850         }
851
852         return 0;
853 }
854
855 /**
856  * set_machine_constraints - sets regulator constraints
857  * @rdev: regulator source
858  * @constraints: constraints to apply
859  *
860  * Allows platform initialisation code to define and constrain
861  * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
862  * Constraints *must* be set by platform code in order for some
863  * regulator operations to proceed i.e. set_voltage, set_current_limit,
864  * set_mode.
865  */
866 static int set_machine_constraints(struct regulator_dev *rdev,
867         const struct regulation_constraints *constraints)
868 {
869         int ret = 0;
870         struct regulator_ops *ops = rdev->desc->ops;
871
872         rdev->constraints = kmemdup(constraints, sizeof(*constraints),
873                                     GFP_KERNEL);
874         if (!rdev->constraints)
875                 return -ENOMEM;
876
877         ret = machine_constraints_voltage(rdev, rdev->constraints);
878         if (ret != 0)
879                 goto out;
880
881         /* do we need to setup our suspend state */
882         if (constraints->initial_state) {
883                 ret = suspend_prepare(rdev, rdev->constraints->initial_state);
884                 if (ret < 0) {
885                         rdev_err(rdev, "failed to set suspend state\n");
886                         rdev->constraints = NULL;
887                         goto out;
888                 }
889         }
890
891         if (constraints->initial_mode) {
892                 if (!ops->set_mode) {
893                         rdev_err(rdev, "no set_mode operation\n");
894                         ret = -EINVAL;
895                         goto out;
896                 }
897
898                 ret = ops->set_mode(rdev, rdev->constraints->initial_mode);
899                 if (ret < 0) {
900                         rdev_err(rdev, "failed to set initial mode: %d\n", ret);
901                         goto out;
902                 }
903         }
904
905         /* If the constraints say the regulator should be on at this point
906          * and we have control then make sure it is enabled.
907          */
908         if ((rdev->constraints->always_on || rdev->constraints->boot_on) &&
909             ops->enable) {
910                 ret = ops->enable(rdev);
911                 if (ret < 0) {
912                         rdev_err(rdev, "failed to enable\n");
913                         rdev->constraints = NULL;
914                         goto out;
915                 }
916         }
917
918         print_constraints(rdev);
919 out:
920         return ret;
921 }
922
923 /**
924  * set_supply - set regulator supply regulator
925  * @rdev: regulator name
926  * @supply_rdev: supply regulator name
927  *
928  * Called by platform initialisation code to set the supply regulator for this
929  * regulator. This ensures that a regulators supply will also be enabled by the
930  * core if it's child is enabled.
931  */
932 static int set_supply(struct regulator_dev *rdev,
933         struct regulator_dev *supply_rdev)
934 {
935         int err;
936
937         err = sysfs_create_link(&rdev->dev.kobj, &supply_rdev->dev.kobj,
938                                 "supply");
939         if (err) {
940                 rdev_err(rdev, "could not add device link %s err %d\n",
941                          supply_rdev->dev.kobj.name, err);
942                        goto out;
943         }
944         rdev->supply = supply_rdev;
945         list_add(&rdev->slist, &supply_rdev->supply_list);
946 out:
947         return err;
948 }
949
950 /**
951  * set_consumer_device_supply - Bind a regulator to a symbolic supply
952  * @rdev:         regulator source
953  * @consumer_dev: device the supply applies to
954  * @consumer_dev_name: dev_name() string for device supply applies to
955  * @supply:       symbolic name for supply
956  *
957  * Allows platform initialisation code to map physical regulator
958  * sources to symbolic names for supplies for use by devices.  Devices
959  * should use these symbolic names to request regulators, avoiding the
960  * need to provide board-specific regulator names as platform data.
961  *
962  * Only one of consumer_dev and consumer_dev_name may be specified.
963  */
964 static int set_consumer_device_supply(struct regulator_dev *rdev,
965         struct device *consumer_dev, const char *consumer_dev_name,
966         const char *supply)
967 {
968         struct regulator_map *node;
969         int has_dev;
970
971         if (consumer_dev && consumer_dev_name)
972                 return -EINVAL;
973
974         if (!consumer_dev_name && consumer_dev)
975                 consumer_dev_name = dev_name(consumer_dev);
976
977         if (supply == NULL)
978                 return -EINVAL;
979
980         if (consumer_dev_name != NULL)
981                 has_dev = 1;
982         else
983                 has_dev = 0;
984
985         list_for_each_entry(node, &regulator_map_list, list) {
986                 if (node->dev_name && consumer_dev_name) {
987                         if (strcmp(node->dev_name, consumer_dev_name) != 0)
988                                 continue;
989                 } else if (node->dev_name || consumer_dev_name) {
990                         continue;
991                 }
992
993                 if (strcmp(node->supply, supply) != 0)
994                         continue;
995
996                 dev_dbg(consumer_dev, "%s/%s is '%s' supply; fail %s/%s\n",
997                         dev_name(&node->regulator->dev),
998                         node->regulator->desc->name,
999                         supply,
1000                         dev_name(&rdev->dev), rdev_get_name(rdev));
1001                 return -EBUSY;
1002         }
1003
1004         node = kzalloc(sizeof(struct regulator_map), GFP_KERNEL);
1005         if (node == NULL)
1006                 return -ENOMEM;
1007
1008         node->regulator = rdev;
1009         node->supply = supply;
1010
1011         if (has_dev) {
1012                 node->dev_name = kstrdup(consumer_dev_name, GFP_KERNEL);
1013                 if (node->dev_name == NULL) {
1014                         kfree(node);
1015                         return -ENOMEM;
1016                 }
1017         }
1018
1019         list_add(&node->list, &regulator_map_list);
1020         return 0;
1021 }
1022
1023 static void unset_regulator_supplies(struct regulator_dev *rdev)
1024 {
1025         struct regulator_map *node, *n;
1026
1027         list_for_each_entry_safe(node, n, &regulator_map_list, list) {
1028                 if (rdev == node->regulator) {
1029                         list_del(&node->list);
1030                         kfree(node->dev_name);
1031                         kfree(node);
1032                 }
1033         }
1034 }
1035
1036 #define REG_STR_SIZE    64
1037
1038 static struct regulator *create_regulator(struct regulator_dev *rdev,
1039                                           struct device *dev,
1040                                           const char *supply_name)
1041 {
1042         struct regulator *regulator;
1043         char buf[REG_STR_SIZE];
1044         int err, size;
1045
1046         regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
1047         if (regulator == NULL)
1048                 return NULL;
1049
1050         mutex_lock(&rdev->mutex);
1051         regulator->rdev = rdev;
1052         list_add(&regulator->list, &rdev->consumer_list);
1053
1054         if (dev) {
1055                 /* create a 'requested_microamps_name' sysfs entry */
1056                 size = scnprintf(buf, REG_STR_SIZE,
1057                                  "microamps_requested_%s-%s",
1058                                  dev_name(dev), supply_name);
1059                 if (size >= REG_STR_SIZE)
1060                         goto overflow_err;
1061
1062                 regulator->dev = dev;
1063                 sysfs_attr_init(&regulator->dev_attr.attr);
1064                 regulator->dev_attr.attr.name = kstrdup(buf, GFP_KERNEL);
1065                 if (regulator->dev_attr.attr.name == NULL)
1066                         goto attr_name_err;
1067
1068                 regulator->dev_attr.attr.mode = 0444;
1069                 regulator->dev_attr.show = device_requested_uA_show;
1070                 err = device_create_file(dev, &regulator->dev_attr);
1071                 if (err < 0) {
1072                         rdev_warn(rdev, "could not add regulator_dev requested microamps sysfs entry\n");
1073                         goto attr_name_err;
1074                 }
1075
1076                 /* also add a link to the device sysfs entry */
1077                 size = scnprintf(buf, REG_STR_SIZE, "%s-%s",
1078                                  dev->kobj.name, supply_name);
1079                 if (size >= REG_STR_SIZE)
1080                         goto attr_err;
1081
1082                 regulator->supply_name = kstrdup(buf, GFP_KERNEL);
1083                 if (regulator->supply_name == NULL)
1084                         goto attr_err;
1085
1086                 err = sysfs_create_link(&rdev->dev.kobj, &dev->kobj,
1087                                         buf);
1088                 if (err) {
1089                         rdev_warn(rdev, "could not add device link %s err %d\n",
1090                                   dev->kobj.name, err);
1091                         goto link_name_err;
1092                 }
1093         }
1094         mutex_unlock(&rdev->mutex);
1095         return regulator;
1096 link_name_err:
1097         kfree(regulator->supply_name);
1098 attr_err:
1099         device_remove_file(regulator->dev, &regulator->dev_attr);
1100 attr_name_err:
1101         kfree(regulator->dev_attr.attr.name);
1102 overflow_err:
1103         list_del(&regulator->list);
1104         kfree(regulator);
1105         mutex_unlock(&rdev->mutex);
1106         return NULL;
1107 }
1108
1109 static int _regulator_get_enable_time(struct regulator_dev *rdev)
1110 {
1111         if (!rdev->desc->ops->enable_time)
1112                 return 0;
1113         return rdev->desc->ops->enable_time(rdev);
1114 }
1115
1116 /* Internal regulator request function */
1117 static struct regulator *_regulator_get(struct device *dev, const char *id,
1118                                         int exclusive)
1119 {
1120         struct regulator_dev *rdev;
1121         struct regulator_map *map;
1122         struct regulator *regulator = ERR_PTR(-ENODEV);
1123         const char *devname = NULL;
1124         int ret;
1125
1126         if (id == NULL) {
1127                 pr_err("get() with no identifier\n");
1128                 return regulator;
1129         }
1130
1131         if (dev)
1132                 devname = dev_name(dev);
1133
1134         mutex_lock(&regulator_list_mutex);
1135
1136         list_for_each_entry(map, &regulator_map_list, list) {
1137                 /* If the mapping has a device set up it must match */
1138                 if (map->dev_name &&
1139                     (!devname || strcmp(map->dev_name, devname)))
1140                         continue;
1141
1142                 if (strcmp(map->supply, id) == 0) {
1143                         rdev = map->regulator;
1144                         goto found;
1145                 }
1146         }
1147
1148         if (board_wants_dummy_regulator) {
1149                 rdev = dummy_regulator_rdev;
1150                 goto found;
1151         }
1152
1153 #ifdef CONFIG_REGULATOR_DUMMY
1154         if (!devname)
1155                 devname = "deviceless";
1156
1157         /* If the board didn't flag that it was fully constrained then
1158          * substitute in a dummy regulator so consumers can continue.
1159          */
1160         if (!has_full_constraints) {
1161                 pr_warn("%s supply %s not found, using dummy regulator\n",
1162                         devname, id);
1163                 rdev = dummy_regulator_rdev;
1164                 goto found;
1165         }
1166 #endif
1167
1168         mutex_unlock(&regulator_list_mutex);
1169         return regulator;
1170
1171 found:
1172         if (rdev->exclusive) {
1173                 regulator = ERR_PTR(-EPERM);
1174                 goto out;
1175         }
1176
1177         if (exclusive && rdev->open_count) {
1178                 regulator = ERR_PTR(-EBUSY);
1179                 goto out;
1180         }
1181
1182         if (!try_module_get(rdev->owner))
1183                 goto out;
1184
1185         regulator = create_regulator(rdev, dev, id);
1186         if (regulator == NULL) {
1187                 regulator = ERR_PTR(-ENOMEM);
1188                 module_put(rdev->owner);
1189         }
1190
1191         rdev->open_count++;
1192         if (exclusive) {
1193                 rdev->exclusive = 1;
1194
1195                 ret = _regulator_is_enabled(rdev);
1196                 if (ret > 0)
1197                         rdev->use_count = 1;
1198                 else
1199                         rdev->use_count = 0;
1200         }
1201
1202 out:
1203         mutex_unlock(&regulator_list_mutex);
1204
1205         return regulator;
1206 }
1207
1208 /**
1209  * regulator_get - lookup and obtain a reference to a regulator.
1210  * @dev: device for regulator "consumer"
1211  * @id: Supply name or regulator ID.
1212  *
1213  * Returns a struct regulator corresponding to the regulator producer,
1214  * or IS_ERR() condition containing errno.
1215  *
1216  * Use of supply names configured via regulator_set_device_supply() is
1217  * strongly encouraged.  It is recommended that the supply name used
1218  * should match the name used for the supply and/or the relevant
1219  * device pins in the datasheet.
1220  */
1221 struct regulator *regulator_get(struct device *dev, const char *id)
1222 {
1223         return _regulator_get(dev, id, 0);
1224 }
1225 EXPORT_SYMBOL_GPL(regulator_get);
1226
1227 /**
1228  * regulator_get_exclusive - obtain exclusive access to a regulator.
1229  * @dev: device for regulator "consumer"
1230  * @id: Supply name or regulator ID.
1231  *
1232  * Returns a struct regulator corresponding to the regulator producer,
1233  * or IS_ERR() condition containing errno.  Other consumers will be
1234  * unable to obtain this reference is held and the use count for the
1235  * regulator will be initialised to reflect the current state of the
1236  * regulator.
1237  *
1238  * This is intended for use by consumers which cannot tolerate shared
1239  * use of the regulator such as those which need to force the
1240  * regulator off for correct operation of the hardware they are
1241  * controlling.
1242  *
1243  * Use of supply names configured via regulator_set_device_supply() is
1244  * strongly encouraged.  It is recommended that the supply name used
1245  * should match the name used for the supply and/or the relevant
1246  * device pins in the datasheet.
1247  */
1248 struct regulator *regulator_get_exclusive(struct device *dev, const char *id)
1249 {
1250         return _regulator_get(dev, id, 1);
1251 }
1252 EXPORT_SYMBOL_GPL(regulator_get_exclusive);
1253
1254 /**
1255  * regulator_put - "free" the regulator source
1256  * @regulator: regulator source
1257  *
1258  * Note: drivers must ensure that all regulator_enable calls made on this
1259  * regulator source are balanced by regulator_disable calls prior to calling
1260  * this function.
1261  */
1262 void regulator_put(struct regulator *regulator)
1263 {
1264         struct regulator_dev *rdev;
1265
1266         if (regulator == NULL || IS_ERR(regulator))
1267                 return;
1268
1269         mutex_lock(&regulator_list_mutex);
1270         rdev = regulator->rdev;
1271
1272         /* remove any sysfs entries */
1273         if (regulator->dev) {
1274                 sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
1275                 kfree(regulator->supply_name);
1276                 device_remove_file(regulator->dev, &regulator->dev_attr);
1277                 kfree(regulator->dev_attr.attr.name);
1278         }
1279         list_del(&regulator->list);
1280         kfree(regulator);
1281
1282         rdev->open_count--;
1283         rdev->exclusive = 0;
1284
1285         module_put(rdev->owner);
1286         mutex_unlock(&regulator_list_mutex);
1287 }
1288 EXPORT_SYMBOL_GPL(regulator_put);
1289
1290 static int _regulator_can_change_status(struct regulator_dev *rdev)
1291 {
1292         if (!rdev->constraints)
1293                 return 0;
1294
1295         if (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_STATUS)
1296                 return 1;
1297         else
1298                 return 0;
1299 }
1300
1301 /* locks held by regulator_enable() */
1302 static int _regulator_enable(struct regulator_dev *rdev)
1303 {
1304         int ret, delay;
1305
1306         if (rdev->use_count == 0) {
1307                 /* do we need to enable the supply regulator first */
1308                 if (rdev->supply) {
1309                         mutex_lock(&rdev->supply->mutex);
1310                         ret = _regulator_enable(rdev->supply);
1311                         mutex_unlock(&rdev->supply->mutex);
1312                         if (ret < 0) {
1313                                 rdev_err(rdev, "failed to enable: %d\n", ret);
1314                                 return ret;
1315                         }
1316                 }
1317         }
1318
1319         /* check voltage and requested load before enabling */
1320         if (rdev->constraints &&
1321             (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS))
1322                 drms_uA_update(rdev);
1323
1324         if (rdev->use_count == 0) {
1325                 /* The regulator may on if it's not switchable or left on */
1326                 ret = _regulator_is_enabled(rdev);
1327                 if (ret == -EINVAL || ret == 0) {
1328                         if (!_regulator_can_change_status(rdev))
1329                                 return -EPERM;
1330
1331                         if (!rdev->desc->ops->enable)
1332                                 return -EINVAL;
1333
1334                         /* Query before enabling in case configuration
1335                          * dependent.  */
1336                         ret = _regulator_get_enable_time(rdev);
1337                         if (ret >= 0) {
1338                                 delay = ret;
1339                         } else {
1340                                 rdev_warn(rdev, "enable_time() failed: %d\n",
1341                                            ret);
1342                                 delay = 0;
1343                         }
1344
1345                         trace_regulator_enable(rdev_get_name(rdev));
1346
1347                         /* Allow the regulator to ramp; it would be useful
1348                          * to extend this for bulk operations so that the
1349                          * regulators can ramp together.  */
1350                         ret = rdev->desc->ops->enable(rdev);
1351                         if (ret < 0)
1352                                 return ret;
1353
1354                         trace_regulator_enable_delay(rdev_get_name(rdev));
1355
1356                         if (delay >= 1000) {
1357                                 mdelay(delay / 1000);
1358                                 udelay(delay % 1000);
1359                         } else if (delay) {
1360                                 udelay(delay);
1361                         }
1362
1363                         trace_regulator_enable_complete(rdev_get_name(rdev));
1364
1365                 } else if (ret < 0) {
1366                         rdev_err(rdev, "is_enabled() failed: %d\n", ret);
1367                         return ret;
1368                 }
1369                 /* Fallthrough on positive return values - already enabled */
1370         }
1371
1372         rdev->use_count++;
1373
1374         return 0;
1375 }
1376
1377 /**
1378  * regulator_enable - enable regulator output
1379  * @regulator: regulator source
1380  *
1381  * Request that the regulator be enabled with the regulator output at
1382  * the predefined voltage or current value.  Calls to regulator_enable()
1383  * must be balanced with calls to regulator_disable().
1384  *
1385  * NOTE: the output value can be set by other drivers, boot loader or may be
1386  * hardwired in the regulator.
1387  */
1388 int regulator_enable(struct regulator *regulator)
1389 {
1390         struct regulator_dev *rdev = regulator->rdev;
1391         int ret = 0;
1392
1393         mutex_lock(&rdev->mutex);
1394         ret = _regulator_enable(rdev);
1395         mutex_unlock(&rdev->mutex);
1396         return ret;
1397 }
1398 EXPORT_SYMBOL_GPL(regulator_enable);
1399
1400 /* locks held by regulator_disable() */
1401 static int _regulator_disable(struct regulator_dev *rdev,
1402                 struct regulator_dev **supply_rdev_ptr)
1403 {
1404         int ret = 0;
1405         *supply_rdev_ptr = NULL;
1406
1407         if (WARN(rdev->use_count <= 0,
1408                  "unbalanced disables for %s\n", rdev_get_name(rdev)))
1409                 return -EIO;
1410
1411         /* are we the last user and permitted to disable ? */
1412         if (rdev->use_count == 1 &&
1413             (rdev->constraints && !rdev->constraints->always_on)) {
1414
1415                 /* we are last user */
1416                 if (_regulator_can_change_status(rdev) &&
1417                     rdev->desc->ops->disable) {
1418                         trace_regulator_disable(rdev_get_name(rdev));
1419
1420                         ret = rdev->desc->ops->disable(rdev);
1421                         if (ret < 0) {
1422                                 rdev_err(rdev, "failed to disable\n");
1423                                 return ret;
1424                         }
1425
1426                         trace_regulator_disable_complete(rdev_get_name(rdev));
1427
1428                         _notifier_call_chain(rdev, REGULATOR_EVENT_DISABLE,
1429                                              NULL);
1430                 }
1431
1432                 /* decrease our supplies ref count and disable if required */
1433                 *supply_rdev_ptr = rdev->supply;
1434
1435                 rdev->use_count = 0;
1436         } else if (rdev->use_count > 1) {
1437
1438                 if (rdev->constraints &&
1439                         (rdev->constraints->valid_ops_mask &
1440                         REGULATOR_CHANGE_DRMS))
1441                         drms_uA_update(rdev);
1442
1443                 rdev->use_count--;
1444         }
1445         return ret;
1446 }
1447
1448 /**
1449  * regulator_disable - disable regulator output
1450  * @regulator: regulator source
1451  *
1452  * Disable the regulator output voltage or current.  Calls to
1453  * regulator_enable() must be balanced with calls to
1454  * regulator_disable().
1455  *
1456  * NOTE: this will only disable the regulator output if no other consumer
1457  * devices have it enabled, the regulator device supports disabling and
1458  * machine constraints permit this operation.
1459  */
1460 int regulator_disable(struct regulator *regulator)
1461 {
1462         struct regulator_dev *rdev = regulator->rdev;
1463         struct regulator_dev *supply_rdev = NULL;
1464         int ret = 0;
1465
1466         mutex_lock(&rdev->mutex);
1467         ret = _regulator_disable(rdev, &supply_rdev);
1468         mutex_unlock(&rdev->mutex);
1469
1470         /* decrease our supplies ref count and disable if required */
1471         while (supply_rdev != NULL) {
1472                 rdev = supply_rdev;
1473
1474                 mutex_lock(&rdev->mutex);
1475                 _regulator_disable(rdev, &supply_rdev);
1476                 mutex_unlock(&rdev->mutex);
1477         }
1478
1479         return ret;
1480 }
1481 EXPORT_SYMBOL_GPL(regulator_disable);
1482
1483 /* locks held by regulator_force_disable() */
1484 static int _regulator_force_disable(struct regulator_dev *rdev,
1485                 struct regulator_dev **supply_rdev_ptr)
1486 {
1487         int ret = 0;
1488
1489         /* force disable */
1490         if (rdev->desc->ops->disable) {
1491                 /* ah well, who wants to live forever... */
1492                 ret = rdev->desc->ops->disable(rdev);
1493                 if (ret < 0) {
1494                         rdev_err(rdev, "failed to force disable\n");
1495                         return ret;
1496                 }
1497                 /* notify other consumers that power has been forced off */
1498                 _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
1499                         REGULATOR_EVENT_DISABLE, NULL);
1500         }
1501
1502         /* decrease our supplies ref count and disable if required */
1503         *supply_rdev_ptr = rdev->supply;
1504
1505         rdev->use_count = 0;
1506         return ret;
1507 }
1508
1509 /**
1510  * regulator_force_disable - force disable regulator output
1511  * @regulator: regulator source
1512  *
1513  * Forcibly disable the regulator output voltage or current.
1514  * NOTE: this *will* disable the regulator output even if other consumer
1515  * devices have it enabled. This should be used for situations when device
1516  * damage will likely occur if the regulator is not disabled (e.g. over temp).
1517  */
1518 int regulator_force_disable(struct regulator *regulator)
1519 {
1520         struct regulator_dev *rdev = regulator->rdev;
1521         struct regulator_dev *supply_rdev = NULL;
1522         int ret;
1523
1524         mutex_lock(&rdev->mutex);
1525         regulator->uA_load = 0;
1526         ret = _regulator_force_disable(rdev, &supply_rdev);
1527         mutex_unlock(&rdev->mutex);
1528
1529         if (supply_rdev)
1530                 regulator_disable(get_device_regulator(rdev_get_dev(supply_rdev)));
1531
1532         return ret;
1533 }
1534 EXPORT_SYMBOL_GPL(regulator_force_disable);
1535
1536 static int _regulator_is_enabled(struct regulator_dev *rdev)
1537 {
1538         /* If we don't know then assume that the regulator is always on */
1539         if (!rdev->desc->ops->is_enabled)
1540                 return 1;
1541
1542         return rdev->desc->ops->is_enabled(rdev);
1543 }
1544
1545 /**
1546  * regulator_is_enabled - is the regulator output enabled
1547  * @regulator: regulator source
1548  *
1549  * Returns positive if the regulator driver backing the source/client
1550  * has requested that the device be enabled, zero if it hasn't, else a
1551  * negative errno code.
1552  *
1553  * Note that the device backing this regulator handle can have multiple
1554  * users, so it might be enabled even if regulator_enable() was never
1555  * called for this particular source.
1556  */
1557 int regulator_is_enabled(struct regulator *regulator)
1558 {
1559         int ret;
1560
1561         mutex_lock(&regulator->rdev->mutex);
1562         ret = _regulator_is_enabled(regulator->rdev);
1563         mutex_unlock(&regulator->rdev->mutex);
1564
1565         return ret;
1566 }
1567 EXPORT_SYMBOL_GPL(regulator_is_enabled);
1568
1569 /**
1570  * regulator_count_voltages - count regulator_list_voltage() selectors
1571  * @regulator: regulator source
1572  *
1573  * Returns number of selectors, or negative errno.  Selectors are
1574  * numbered starting at zero, and typically correspond to bitfields
1575  * in hardware registers.
1576  */
1577 int regulator_count_voltages(struct regulator *regulator)
1578 {
1579         struct regulator_dev    *rdev = regulator->rdev;
1580
1581         return rdev->desc->n_voltages ? : -EINVAL;
1582 }
1583 EXPORT_SYMBOL_GPL(regulator_count_voltages);
1584
1585 /**
1586  * regulator_list_voltage - enumerate supported voltages
1587  * @regulator: regulator source
1588  * @selector: identify voltage to list
1589  * Context: can sleep
1590  *
1591  * Returns a voltage that can be passed to @regulator_set_voltage(),
1592  * zero if this selector code can't be used on this system, or a
1593  * negative errno.
1594  */
1595 int regulator_list_voltage(struct regulator *regulator, unsigned selector)
1596 {
1597         struct regulator_dev    *rdev = regulator->rdev;
1598         struct regulator_ops    *ops = rdev->desc->ops;
1599         int                     ret;
1600
1601         if (!ops->list_voltage || selector >= rdev->desc->n_voltages)
1602                 return -EINVAL;
1603
1604         mutex_lock(&rdev->mutex);
1605         ret = ops->list_voltage(rdev, selector);
1606         mutex_unlock(&rdev->mutex);
1607
1608         if (ret > 0) {
1609                 if (ret < rdev->constraints->min_uV)
1610                         ret = 0;
1611                 else if (ret > rdev->constraints->max_uV)
1612                         ret = 0;
1613         }
1614
1615         return ret;
1616 }
1617 EXPORT_SYMBOL_GPL(regulator_list_voltage);
1618
1619 /**
1620  * regulator_is_supported_voltage - check if a voltage range can be supported
1621  *
1622  * @regulator: Regulator to check.
1623  * @min_uV: Minimum required voltage in uV.
1624  * @max_uV: Maximum required voltage in uV.
1625  *
1626  * Returns a boolean or a negative error code.
1627  */
1628 int regulator_is_supported_voltage(struct regulator *regulator,
1629                                    int min_uV, int max_uV)
1630 {
1631         int i, voltages, ret;
1632
1633         ret = regulator_count_voltages(regulator);
1634         if (ret < 0)
1635                 return ret;
1636         voltages = ret;
1637
1638         for (i = 0; i < voltages; i++) {
1639                 ret = regulator_list_voltage(regulator, i);
1640
1641                 if (ret >= min_uV && ret <= max_uV)
1642                         return 1;
1643         }
1644
1645         return 0;
1646 }
1647
1648 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
1649                                      int min_uV, int max_uV)
1650 {
1651         int ret;
1652         int delay = 0;
1653         unsigned int selector;
1654
1655         trace_regulator_set_voltage(rdev_get_name(rdev), min_uV, max_uV);
1656
1657         min_uV += rdev->constraints->uV_offset;
1658         max_uV += rdev->constraints->uV_offset;
1659
1660         if (rdev->desc->ops->set_voltage) {
1661                 ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV,
1662                                                    &selector);
1663
1664                 if (rdev->desc->ops->list_voltage)
1665                         selector = rdev->desc->ops->list_voltage(rdev,
1666                                                                  selector);
1667                 else
1668                         selector = -1;
1669         } else if (rdev->desc->ops->set_voltage_sel) {
1670                 int best_val = INT_MAX;
1671                 int i;
1672
1673                 selector = 0;
1674
1675                 /* Find the smallest voltage that falls within the specified
1676                  * range.
1677                  */
1678                 for (i = 0; i < rdev->desc->n_voltages; i++) {
1679                         ret = rdev->desc->ops->list_voltage(rdev, i);
1680                         if (ret < 0)
1681                                 continue;
1682
1683                         if (ret < best_val && ret >= min_uV && ret <= max_uV) {
1684                                 best_val = ret;
1685                                 selector = i;
1686                         }
1687                 }
1688
1689                 /*
1690                  * If we can't obtain the old selector there is not enough
1691                  * info to call set_voltage_time_sel().
1692                  */
1693                 if (rdev->desc->ops->set_voltage_time_sel &&
1694                     rdev->desc->ops->get_voltage_sel) {
1695                         unsigned int old_selector = 0;
1696
1697                         ret = rdev->desc->ops->get_voltage_sel(rdev);
1698                         if (ret < 0)
1699                                 return ret;
1700                         old_selector = ret;
1701                         delay = rdev->desc->ops->set_voltage_time_sel(rdev,
1702                                                 old_selector, selector);
1703                 }
1704
1705                 if (best_val != INT_MAX) {
1706                         ret = rdev->desc->ops->set_voltage_sel(rdev, selector);
1707                         selector = best_val;
1708                 } else {
1709                         ret = -EINVAL;
1710                 }
1711         } else {
1712                 ret = -EINVAL;
1713         }
1714
1715         /* Insert any necessary delays */
1716         if (delay >= 1000) {
1717                 mdelay(delay / 1000);
1718                 udelay(delay % 1000);
1719         } else if (delay) {
1720                 udelay(delay);
1721         }
1722
1723         if (ret == 0)
1724                 _notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE,
1725                                      NULL);
1726
1727         trace_regulator_set_voltage_complete(rdev_get_name(rdev), selector);
1728
1729         return ret;
1730 }
1731
1732 /**
1733  * regulator_set_voltage - set regulator output voltage
1734  * @regulator: regulator source
1735  * @min_uV: Minimum required voltage in uV
1736  * @max_uV: Maximum acceptable voltage in uV
1737  *
1738  * Sets a voltage regulator to the desired output voltage. This can be set
1739  * during any regulator state. IOW, regulator can be disabled or enabled.
1740  *
1741  * If the regulator is enabled then the voltage will change to the new value
1742  * immediately otherwise if the regulator is disabled the regulator will
1743  * output at the new voltage when enabled.
1744  *
1745  * NOTE: If the regulator is shared between several devices then the lowest
1746  * request voltage that meets the system constraints will be used.
1747  * Regulator system constraints must be set for this regulator before
1748  * calling this function otherwise this call will fail.
1749  */
1750 int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
1751 {
1752         struct regulator_dev *rdev = regulator->rdev;
1753         int ret = 0;
1754
1755         mutex_lock(&rdev->mutex);
1756
1757         /* If we're setting the same range as last time the change
1758          * should be a noop (some cpufreq implementations use the same
1759          * voltage for multiple frequencies, for example).
1760          */
1761         if (regulator->min_uV == min_uV && regulator->max_uV == max_uV)
1762                 goto out;
1763
1764         /* sanity check */
1765         if (!rdev->desc->ops->set_voltage &&
1766             !rdev->desc->ops->set_voltage_sel) {
1767                 ret = -EINVAL;
1768                 goto out;
1769         }
1770
1771         /* constraints check */
1772         ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
1773         if (ret < 0)
1774                 goto out;
1775         regulator->min_uV = min_uV;
1776         regulator->max_uV = max_uV;
1777
1778         ret = regulator_check_consumers(rdev, &min_uV, &max_uV);
1779         if (ret < 0)
1780                 goto out;
1781
1782         ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
1783
1784 out:
1785         mutex_unlock(&rdev->mutex);
1786         return ret;
1787 }
1788 EXPORT_SYMBOL_GPL(regulator_set_voltage);
1789
1790 /**
1791  * regulator_set_voltage_time - get raise/fall time
1792  * @regulator: regulator source
1793  * @old_uV: starting voltage in microvolts
1794  * @new_uV: target voltage in microvolts
1795  *
1796  * Provided with the starting and ending voltage, this function attempts to
1797  * calculate the time in microseconds required to rise or fall to this new
1798  * voltage.
1799  */
1800 int regulator_set_voltage_time(struct regulator *regulator,
1801                                int old_uV, int new_uV)
1802 {
1803         struct regulator_dev    *rdev = regulator->rdev;
1804         struct regulator_ops    *ops = rdev->desc->ops;
1805         int old_sel = -1;
1806         int new_sel = -1;
1807         int voltage;
1808         int i;
1809
1810         /* Currently requires operations to do this */
1811         if (!ops->list_voltage || !ops->set_voltage_time_sel
1812             || !rdev->desc->n_voltages)
1813                 return -EINVAL;
1814
1815         for (i = 0; i < rdev->desc->n_voltages; i++) {
1816                 /* We only look for exact voltage matches here */
1817                 voltage = regulator_list_voltage(regulator, i);
1818                 if (voltage < 0)
1819                         return -EINVAL;
1820                 if (voltage == 0)
1821                         continue;
1822                 if (voltage == old_uV)
1823                         old_sel = i;
1824                 if (voltage == new_uV)
1825                         new_sel = i;
1826         }
1827
1828         if (old_sel < 0 || new_sel < 0)
1829                 return -EINVAL;
1830
1831         return ops->set_voltage_time_sel(rdev, old_sel, new_sel);
1832 }
1833 EXPORT_SYMBOL_GPL(regulator_set_voltage_time);
1834
1835 /**
1836  * regulator_sync_voltage - re-apply last regulator output voltage
1837  * @regulator: regulator source
1838  *
1839  * Re-apply the last configured voltage.  This is intended to be used
1840  * where some external control source the consumer is cooperating with
1841  * has caused the configured voltage to change.
1842  */
1843 int regulator_sync_voltage(struct regulator *regulator)
1844 {
1845         struct regulator_dev *rdev = regulator->rdev;
1846         int ret, min_uV, max_uV;
1847
1848         mutex_lock(&rdev->mutex);
1849
1850         if (!rdev->desc->ops->set_voltage &&
1851             !rdev->desc->ops->set_voltage_sel) {
1852                 ret = -EINVAL;
1853                 goto out;
1854         }
1855
1856         /* This is only going to work if we've had a voltage configured. */
1857         if (!regulator->min_uV && !regulator->max_uV) {
1858                 ret = -EINVAL;
1859                 goto out;
1860         }
1861
1862         min_uV = regulator->min_uV;
1863         max_uV = regulator->max_uV;
1864
1865         /* This should be a paranoia check... */
1866         ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
1867         if (ret < 0)
1868                 goto out;
1869
1870         ret = regulator_check_consumers(rdev, &min_uV, &max_uV);
1871         if (ret < 0)
1872                 goto out;
1873
1874         ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
1875
1876 out:
1877         mutex_unlock(&rdev->mutex);
1878         return ret;
1879 }
1880 EXPORT_SYMBOL_GPL(regulator_sync_voltage);
1881
1882 static int _regulator_get_voltage(struct regulator_dev *rdev)
1883 {
1884         int sel, ret;
1885
1886         if (rdev->desc->ops->get_voltage_sel) {
1887                 sel = rdev->desc->ops->get_voltage_sel(rdev);
1888                 if (sel < 0)
1889                         return sel;
1890                 ret = rdev->desc->ops->list_voltage(rdev, sel);
1891         } else if (rdev->desc->ops->get_voltage) {
1892                 ret = rdev->desc->ops->get_voltage(rdev);
1893         } else {
1894                 return -EINVAL;
1895         }
1896
1897         if (ret < 0)
1898                 return ret;
1899         return ret - rdev->constraints->uV_offset;
1900 }
1901
1902 /**
1903  * regulator_get_voltage - get regulator output voltage
1904  * @regulator: regulator source
1905  *
1906  * This returns the current regulator voltage in uV.
1907  *
1908  * NOTE: If the regulator is disabled it will return the voltage value. This
1909  * function should not be used to determine regulator state.
1910  */
1911 int regulator_get_voltage(struct regulator *regulator)
1912 {
1913         int ret;
1914
1915         mutex_lock(&regulator->rdev->mutex);
1916
1917         ret = _regulator_get_voltage(regulator->rdev);
1918
1919         mutex_unlock(&regulator->rdev->mutex);
1920
1921         return ret;
1922 }
1923 EXPORT_SYMBOL_GPL(regulator_get_voltage);
1924
1925 /**
1926  * regulator_set_current_limit - set regulator output current limit
1927  * @regulator: regulator source
1928  * @min_uA: Minimuum supported current in uA
1929  * @max_uA: Maximum supported current in uA
1930  *
1931  * Sets current sink to the desired output current. This can be set during
1932  * any regulator state. IOW, regulator can be disabled or enabled.
1933  *
1934  * If the regulator is enabled then the current will change to the new value
1935  * immediately otherwise if the regulator is disabled the regulator will
1936  * output at the new current when enabled.
1937  *
1938  * NOTE: Regulator system constraints must be set for this regulator before
1939  * calling this function otherwise this call will fail.
1940  */
1941 int regulator_set_current_limit(struct regulator *regulator,
1942                                int min_uA, int max_uA)
1943 {
1944         struct regulator_dev *rdev = regulator->rdev;
1945         int ret;
1946
1947         mutex_lock(&rdev->mutex);
1948
1949         /* sanity check */
1950         if (!rdev->desc->ops->set_current_limit) {
1951                 ret = -EINVAL;
1952                 goto out;
1953         }
1954
1955         /* constraints check */
1956         ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
1957         if (ret < 0)
1958                 goto out;
1959
1960         ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
1961 out:
1962         mutex_unlock(&rdev->mutex);
1963         return ret;
1964 }
1965 EXPORT_SYMBOL_GPL(regulator_set_current_limit);
1966
1967 static int _regulator_get_current_limit(struct regulator_dev *rdev)
1968 {
1969         int ret;
1970
1971         mutex_lock(&rdev->mutex);
1972
1973         /* sanity check */
1974         if (!rdev->desc->ops->get_current_limit) {
1975                 ret = -EINVAL;
1976                 goto out;
1977         }
1978
1979         ret = rdev->desc->ops->get_current_limit(rdev);
1980 out:
1981         mutex_unlock(&rdev->mutex);
1982         return ret;
1983 }
1984
1985 /**
1986  * regulator_get_current_limit - get regulator output current
1987  * @regulator: regulator source
1988  *
1989  * This returns the current supplied by the specified current sink in uA.
1990  *
1991  * NOTE: If the regulator is disabled it will return the current value. This
1992  * function should not be used to determine regulator state.
1993  */
1994 int regulator_get_current_limit(struct regulator *regulator)
1995 {
1996         return _regulator_get_current_limit(regulator->rdev);
1997 }
1998 EXPORT_SYMBOL_GPL(regulator_get_current_limit);
1999
2000 /**
2001  * regulator_set_mode - set regulator operating mode
2002  * @regulator: regulator source
2003  * @mode: operating mode - one of the REGULATOR_MODE constants
2004  *
2005  * Set regulator operating mode to increase regulator efficiency or improve
2006  * regulation performance.
2007  *
2008  * NOTE: Regulator system constraints must be set for this regulator before
2009  * calling this function otherwise this call will fail.
2010  */
2011 int regulator_set_mode(struct regulator *regulator, unsigned int mode)
2012 {
2013         struct regulator_dev *rdev = regulator->rdev;
2014         int ret;
2015         int regulator_curr_mode;
2016
2017         mutex_lock(&rdev->mutex);
2018
2019         /* sanity check */
2020         if (!rdev->desc->ops->set_mode) {
2021                 ret = -EINVAL;
2022                 goto out;
2023         }
2024
2025         /* return if the same mode is requested */
2026         if (rdev->desc->ops->get_mode) {
2027                 regulator_curr_mode = rdev->desc->ops->get_mode(rdev);
2028                 if (regulator_curr_mode == mode) {
2029                         ret = 0;
2030                         goto out;
2031                 }
2032         }
2033
2034         /* constraints check */
2035         ret = regulator_mode_constrain(rdev, &mode);
2036         if (ret < 0)
2037                 goto out;
2038
2039         ret = rdev->desc->ops->set_mode(rdev, mode);
2040 out:
2041         mutex_unlock(&rdev->mutex);
2042         return ret;
2043 }
2044 EXPORT_SYMBOL_GPL(regulator_set_mode);
2045
2046 static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
2047 {
2048         int ret;
2049
2050         mutex_lock(&rdev->mutex);
2051
2052         /* sanity check */
2053         if (!rdev->desc->ops->get_mode) {
2054                 ret = -EINVAL;
2055                 goto out;
2056         }
2057
2058         ret = rdev->desc->ops->get_mode(rdev);
2059 out:
2060         mutex_unlock(&rdev->mutex);
2061         return ret;
2062 }
2063
2064 /**
2065  * regulator_get_mode - get regulator operating mode
2066  * @regulator: regulator source
2067  *
2068  * Get the current regulator operating mode.
2069  */
2070 unsigned int regulator_get_mode(struct regulator *regulator)
2071 {
2072         return _regulator_get_mode(regulator->rdev);
2073 }
2074 EXPORT_SYMBOL_GPL(regulator_get_mode);
2075
2076 /**
2077  * regulator_set_optimum_mode - set regulator optimum operating mode
2078  * @regulator: regulator source
2079  * @uA_load: load current
2080  *
2081  * Notifies the regulator core of a new device load. This is then used by
2082  * DRMS (if enabled by constraints) to set the most efficient regulator
2083  * operating mode for the new regulator loading.
2084  *
2085  * Consumer devices notify their supply regulator of the maximum power
2086  * they will require (can be taken from device datasheet in the power
2087  * consumption tables) when they change operational status and hence power
2088  * state. Examples of operational state changes that can affect power
2089  * consumption are :-
2090  *
2091  *    o Device is opened / closed.
2092  *    o Device I/O is about to begin or has just finished.
2093  *    o Device is idling in between work.
2094  *
2095  * This information is also exported via sysfs to userspace.
2096  *
2097  * DRMS will sum the total requested load on the regulator and change
2098  * to the most efficient operating mode if platform constraints allow.
2099  *
2100  * Returns the new regulator mode or error.
2101  */
2102 int regulator_set_optimum_mode(struct regulator *regulator, int uA_load)
2103 {
2104         struct regulator_dev *rdev = regulator->rdev;
2105         struct regulator *consumer;
2106         int ret, output_uV, input_uV, total_uA_load = 0;
2107         unsigned int mode;
2108
2109         mutex_lock(&rdev->mutex);
2110
2111         /*
2112          * first check to see if we can set modes at all, otherwise just
2113          * tell the consumer everything is OK.
2114          */
2115         regulator->uA_load = uA_load;
2116         ret = regulator_check_drms(rdev);
2117         if (ret < 0) {
2118                 ret = 0;
2119                 goto out;
2120         }
2121
2122         if (!rdev->desc->ops->get_optimum_mode)
2123                 goto out;
2124
2125         /*
2126          * we can actually do this so any errors are indicators of
2127          * potential real failure.
2128          */
2129         ret = -EINVAL;
2130
2131         /* get output voltage */
2132         output_uV = _regulator_get_voltage(rdev);
2133         if (output_uV <= 0) {
2134                 rdev_err(rdev, "invalid output voltage found\n");
2135                 goto out;
2136         }
2137
2138         /* get input voltage */
2139         input_uV = 0;
2140         if (rdev->supply)
2141                 input_uV = _regulator_get_voltage(rdev->supply);
2142         if (input_uV <= 0)
2143                 input_uV = rdev->constraints->input_uV;
2144         if (input_uV <= 0) {
2145                 rdev_err(rdev, "invalid input voltage found\n");
2146                 goto out;
2147         }
2148
2149         /* calc total requested load for this regulator */
2150         list_for_each_entry(consumer, &rdev->consumer_list, list)
2151                 total_uA_load += consumer->uA_load;
2152
2153         mode = rdev->desc->ops->get_optimum_mode(rdev,
2154                                                  input_uV, output_uV,
2155                                                  total_uA_load);
2156         ret = regulator_mode_constrain(rdev, &mode);
2157         if (ret < 0) {
2158                 rdev_err(rdev, "failed to get optimum mode @ %d uA %d -> %d uV\n",
2159                          total_uA_load, input_uV, output_uV);
2160                 goto out;
2161         }
2162
2163         ret = rdev->desc->ops->set_mode(rdev, mode);
2164         if (ret < 0) {
2165                 rdev_err(rdev, "failed to set optimum mode %x\n", mode);
2166                 goto out;
2167         }
2168         ret = mode;
2169 out:
2170         mutex_unlock(&rdev->mutex);
2171         return ret;
2172 }
2173 EXPORT_SYMBOL_GPL(regulator_set_optimum_mode);
2174
2175 /**
2176  * regulator_register_notifier - register regulator event notifier
2177  * @regulator: regulator source
2178  * @nb: notifier block
2179  *
2180  * Register notifier block to receive regulator events.
2181  */
2182 int regulator_register_notifier(struct regulator *regulator,
2183                               struct notifier_block *nb)
2184 {
2185         return blocking_notifier_chain_register(&regulator->rdev->notifier,
2186                                                 nb);
2187 }
2188 EXPORT_SYMBOL_GPL(regulator_register_notifier);
2189
2190 /**
2191  * regulator_unregister_notifier - unregister regulator event notifier
2192  * @regulator: regulator source
2193  * @nb: notifier block
2194  *
2195  * Unregister regulator event notifier block.
2196  */
2197 int regulator_unregister_notifier(struct regulator *regulator,
2198                                 struct notifier_block *nb)
2199 {
2200         return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
2201                                                   nb);
2202 }
2203 EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
2204
2205 /* notify regulator consumers and downstream regulator consumers.
2206  * Note mutex must be held by caller.
2207  */
2208 static void _notifier_call_chain(struct regulator_dev *rdev,
2209                                   unsigned long event, void *data)
2210 {
2211         struct regulator_dev *_rdev;
2212
2213         /* call rdev chain first */
2214         blocking_notifier_call_chain(&rdev->notifier, event, NULL);
2215
2216         /* now notify regulator we supply */
2217         list_for_each_entry(_rdev, &rdev->supply_list, slist) {
2218                 mutex_lock(&_rdev->mutex);
2219                 _notifier_call_chain(_rdev, event, data);
2220                 mutex_unlock(&_rdev->mutex);
2221         }
2222 }
2223
2224 /**
2225  * regulator_bulk_get - get multiple regulator consumers
2226  *
2227  * @dev:           Device to supply
2228  * @num_consumers: Number of consumers to register
2229  * @consumers:     Configuration of consumers; clients are stored here.
2230  *
2231  * @return 0 on success, an errno on failure.
2232  *
2233  * This helper function allows drivers to get several regulator
2234  * consumers in one operation.  If any of the regulators cannot be
2235  * acquired then any regulators that were allocated will be freed
2236  * before returning to the caller.
2237  */
2238 int regulator_bulk_get(struct device *dev, int num_consumers,
2239                        struct regulator_bulk_data *consumers)
2240 {
2241         int i;
2242         int ret;
2243
2244         for (i = 0; i < num_consumers; i++)
2245                 consumers[i].consumer = NULL;
2246
2247         for (i = 0; i < num_consumers; i++) {
2248                 consumers[i].consumer = regulator_get(dev,
2249                                                       consumers[i].supply);
2250                 if (IS_ERR(consumers[i].consumer)) {
2251                         ret = PTR_ERR(consumers[i].consumer);
2252                         dev_err(dev, "Failed to get supply '%s': %d\n",
2253                                 consumers[i].supply, ret);
2254                         consumers[i].consumer = NULL;
2255                         goto err;
2256                 }
2257         }
2258
2259         return 0;
2260
2261 err:
2262         for (i = 0; i < num_consumers && consumers[i].consumer; i++)
2263                 regulator_put(consumers[i].consumer);
2264
2265         return ret;
2266 }
2267 EXPORT_SYMBOL_GPL(regulator_bulk_get);
2268
2269 static void regulator_bulk_enable_async(void *data, async_cookie_t cookie)
2270 {
2271         struct regulator_bulk_data *bulk = data;
2272
2273         bulk->ret = regulator_enable(bulk->consumer);
2274 }
2275
2276 /**
2277  * regulator_bulk_enable - enable multiple regulator consumers
2278  *
2279  * @num_consumers: Number of consumers
2280  * @consumers:     Consumer data; clients are stored here.
2281  * @return         0 on success, an errno on failure
2282  *
2283  * This convenience API allows consumers to enable multiple regulator
2284  * clients in a single API call.  If any consumers cannot be enabled
2285  * then any others that were enabled will be disabled again prior to
2286  * return.
2287  */
2288 int regulator_bulk_enable(int num_consumers,
2289                           struct regulator_bulk_data *consumers)
2290 {
2291         LIST_HEAD(async_domain);
2292         int i;
2293         int ret = 0;
2294
2295         for (i = 0; i < num_consumers; i++)
2296                 async_schedule_domain(regulator_bulk_enable_async,
2297                                       &consumers[i], &async_domain);
2298
2299         async_synchronize_full_domain(&async_domain);
2300
2301         /* If any consumer failed we need to unwind any that succeeded */
2302         for (i = 0; i < num_consumers; i++) {
2303                 if (consumers[i].ret != 0) {
2304                         ret = consumers[i].ret;
2305                         goto err;
2306                 }
2307         }
2308
2309         return 0;
2310
2311 err:
2312         for (i = 0; i < num_consumers; i++)
2313                 if (consumers[i].ret == 0)
2314                         regulator_disable(consumers[i].consumer);
2315                 else
2316                         pr_err("Failed to enable %s: %d\n",
2317                                consumers[i].supply, consumers[i].ret);
2318
2319         return ret;
2320 }
2321 EXPORT_SYMBOL_GPL(regulator_bulk_enable);
2322
2323 /**
2324  * regulator_bulk_disable - disable multiple regulator consumers
2325  *
2326  * @num_consumers: Number of consumers
2327  * @consumers:     Consumer data; clients are stored here.
2328  * @return         0 on success, an errno on failure
2329  *
2330  * This convenience API allows consumers to disable multiple regulator
2331  * clients in a single API call.  If any consumers cannot be enabled
2332  * then any others that were disabled will be disabled again prior to
2333  * return.
2334  */
2335 int regulator_bulk_disable(int num_consumers,
2336                            struct regulator_bulk_data *consumers)
2337 {
2338         int i;
2339         int ret;
2340
2341         for (i = 0; i < num_consumers; i++) {
2342                 ret = regulator_disable(consumers[i].consumer);
2343                 if (ret != 0)
2344                         goto err;
2345         }
2346
2347         return 0;
2348
2349 err:
2350         pr_err("Failed to disable %s: %d\n", consumers[i].supply, ret);
2351         for (--i; i >= 0; --i)
2352                 regulator_enable(consumers[i].consumer);
2353
2354         return ret;
2355 }
2356 EXPORT_SYMBOL_GPL(regulator_bulk_disable);
2357
2358 /**
2359  * regulator_bulk_free - free multiple regulator consumers
2360  *
2361  * @num_consumers: Number of consumers
2362  * @consumers:     Consumer data; clients are stored here.
2363  *
2364  * This convenience API allows consumers to free multiple regulator
2365  * clients in a single API call.
2366  */
2367 void regulator_bulk_free(int num_consumers,
2368                          struct regulator_bulk_data *consumers)
2369 {
2370         int i;
2371
2372         for (i = 0; i < num_consumers; i++) {
2373                 regulator_put(consumers[i].consumer);
2374                 consumers[i].consumer = NULL;
2375         }
2376 }
2377 EXPORT_SYMBOL_GPL(regulator_bulk_free);
2378
2379 /**
2380  * regulator_notifier_call_chain - call regulator event notifier
2381  * @rdev: regulator source
2382  * @event: notifier block
2383  * @data: callback-specific data.
2384  *
2385  * Called by regulator drivers to notify clients a regulator event has
2386  * occurred. We also notify regulator clients downstream.
2387  * Note lock must be held by caller.
2388  */
2389 int regulator_notifier_call_chain(struct regulator_dev *rdev,
2390                                   unsigned long event, void *data)
2391 {
2392         _notifier_call_chain(rdev, event, data);
2393         return NOTIFY_DONE;
2394
2395 }
2396 EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
2397
2398 /**
2399  * regulator_mode_to_status - convert a regulator mode into a status
2400  *
2401  * @mode: Mode to convert
2402  *
2403  * Convert a regulator mode into a status.
2404  */
2405 int regulator_mode_to_status(unsigned int mode)
2406 {
2407         switch (mode) {
2408         case REGULATOR_MODE_FAST:
2409                 return REGULATOR_STATUS_FAST;
2410         case REGULATOR_MODE_NORMAL:
2411                 return REGULATOR_STATUS_NORMAL;
2412         case REGULATOR_MODE_IDLE:
2413                 return REGULATOR_STATUS_IDLE;
2414         case REGULATOR_STATUS_STANDBY:
2415                 return REGULATOR_STATUS_STANDBY;
2416         default:
2417                 return 0;
2418         }
2419 }
2420 EXPORT_SYMBOL_GPL(regulator_mode_to_status);
2421
2422 /*
2423  * To avoid cluttering sysfs (and memory) with useless state, only
2424  * create attributes that can be meaningfully displayed.
2425  */
2426 static int add_regulator_attributes(struct regulator_dev *rdev)
2427 {
2428         struct device           *dev = &rdev->dev;
2429         struct regulator_ops    *ops = rdev->desc->ops;
2430         int                     status = 0;
2431
2432         /* some attributes need specific methods to be displayed */
2433         if (ops->get_voltage || ops->get_voltage_sel) {
2434                 status = device_create_file(dev, &dev_attr_microvolts);
2435                 if (status < 0)
2436                         return status;
2437         }
2438         if (ops->get_current_limit) {
2439                 status = device_create_file(dev, &dev_attr_microamps);
2440                 if (status < 0)
2441                         return status;
2442         }
2443         if (ops->get_mode) {
2444                 status = device_create_file(dev, &dev_attr_opmode);
2445                 if (status < 0)
2446                         return status;
2447         }
2448         if (ops->is_enabled) {
2449                 status = device_create_file(dev, &dev_attr_state);
2450                 if (status < 0)
2451                         return status;
2452         }
2453         if (ops->get_status) {
2454                 status = device_create_file(dev, &dev_attr_status);
2455                 if (status < 0)
2456                         return status;
2457         }
2458
2459         /* some attributes are type-specific */
2460         if (rdev->desc->type == REGULATOR_CURRENT) {
2461                 status = device_create_file(dev, &dev_attr_requested_microamps);
2462                 if (status < 0)
2463                         return status;
2464         }
2465
2466         /* all the other attributes exist to support constraints;
2467          * don't show them if there are no constraints, or if the
2468          * relevant supporting methods are missing.
2469          */
2470         if (!rdev->constraints)
2471                 return status;
2472
2473         /* constraints need specific supporting methods */
2474         if (ops->set_voltage || ops->set_voltage_sel) {
2475                 status = device_create_file(dev, &dev_attr_min_microvolts);
2476                 if (status < 0)
2477                         return status;
2478                 status = device_create_file(dev, &dev_attr_max_microvolts);
2479                 if (status < 0)
2480                         return status;
2481         }
2482         if (ops->set_current_limit) {
2483                 status = device_create_file(dev, &dev_attr_min_microamps);
2484                 if (status < 0)
2485                         return status;
2486                 status = device_create_file(dev, &dev_attr_max_microamps);
2487                 if (status < 0)
2488                         return status;
2489         }
2490
2491         /* suspend mode constraints need multiple supporting methods */
2492         if (!(ops->set_suspend_enable && ops->set_suspend_disable))
2493                 return status;
2494
2495         status = device_create_file(dev, &dev_attr_suspend_standby_state);
2496         if (status < 0)
2497                 return status;
2498         status = device_create_file(dev, &dev_attr_suspend_mem_state);
2499         if (status < 0)
2500                 return status;
2501         status = device_create_file(dev, &dev_attr_suspend_disk_state);
2502         if (status < 0)
2503                 return status;
2504
2505         if (ops->set_suspend_voltage) {
2506                 status = device_create_file(dev,
2507                                 &dev_attr_suspend_standby_microvolts);
2508                 if (status < 0)
2509                         return status;
2510                 status = device_create_file(dev,
2511                                 &dev_attr_suspend_mem_microvolts);
2512                 if (status < 0)
2513                         return status;
2514                 status = device_create_file(dev,
2515                                 &dev_attr_suspend_disk_microvolts);
2516                 if (status < 0)
2517                         return status;
2518         }
2519
2520         if (ops->set_suspend_mode) {
2521                 status = device_create_file(dev,
2522                                 &dev_attr_suspend_standby_mode);
2523                 if (status < 0)
2524                         return status;
2525                 status = device_create_file(dev,
2526                                 &dev_attr_suspend_mem_mode);
2527                 if (status < 0)
2528                         return status;
2529                 status = device_create_file(dev,
2530                                 &dev_attr_suspend_disk_mode);
2531                 if (status < 0)
2532                         return status;
2533         }
2534
2535         return status;
2536 }
2537
2538 static void rdev_init_debugfs(struct regulator_dev *rdev)
2539 {
2540 #ifdef CONFIG_DEBUG_FS
2541         rdev->debugfs = debugfs_create_dir(rdev_get_name(rdev), debugfs_root);
2542         if (IS_ERR(rdev->debugfs) || !rdev->debugfs) {
2543                 rdev_warn(rdev, "Failed to create debugfs directory\n");
2544                 rdev->debugfs = NULL;
2545                 return;
2546         }
2547
2548         debugfs_create_u32("use_count", 0444, rdev->debugfs,
2549                            &rdev->use_count);
2550         debugfs_create_u32("open_count", 0444, rdev->debugfs,
2551                            &rdev->open_count);
2552 #endif
2553 }
2554
2555 /**
2556  * regulator_register - register regulator
2557  * @regulator_desc: regulator to register
2558  * @dev: struct device for the regulator
2559  * @init_data: platform provided init data, passed through by driver
2560  * @driver_data: private regulator data
2561  *
2562  * Called by regulator drivers to register a regulator.
2563  * Returns 0 on success.
2564  */
2565 struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc,
2566         struct device *dev, const struct regulator_init_data *init_data,
2567         void *driver_data)
2568 {
2569         static atomic_t regulator_no = ATOMIC_INIT(0);
2570         struct regulator_dev *rdev;
2571         int ret, i;
2572
2573         if (regulator_desc == NULL)
2574                 return ERR_PTR(-EINVAL);
2575
2576         if (regulator_desc->name == NULL || regulator_desc->ops == NULL)
2577                 return ERR_PTR(-EINVAL);
2578
2579         if (regulator_desc->type != REGULATOR_VOLTAGE &&
2580             regulator_desc->type != REGULATOR_CURRENT)
2581                 return ERR_PTR(-EINVAL);
2582
2583         if (!init_data)
2584                 return ERR_PTR(-EINVAL);
2585
2586         /* Only one of each should be implemented */
2587         WARN_ON(regulator_desc->ops->get_voltage &&
2588                 regulator_desc->ops->get_voltage_sel);
2589         WARN_ON(regulator_desc->ops->set_voltage &&
2590                 regulator_desc->ops->set_voltage_sel);
2591
2592         /* If we're using selectors we must implement list_voltage. */
2593         if (regulator_desc->ops->get_voltage_sel &&
2594             !regulator_desc->ops->list_voltage) {
2595                 return ERR_PTR(-EINVAL);
2596         }
2597         if (regulator_desc->ops->set_voltage_sel &&
2598             !regulator_desc->ops->list_voltage) {
2599                 return ERR_PTR(-EINVAL);
2600         }
2601
2602         rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
2603         if (rdev == NULL)
2604                 return ERR_PTR(-ENOMEM);
2605
2606         mutex_lock(&regulator_list_mutex);
2607
2608         mutex_init(&rdev->mutex);
2609         rdev->reg_data = driver_data;
2610         rdev->owner = regulator_desc->owner;
2611         rdev->desc = regulator_desc;
2612         INIT_LIST_HEAD(&rdev->consumer_list);
2613         INIT_LIST_HEAD(&rdev->supply_list);
2614         INIT_LIST_HEAD(&rdev->list);
2615         INIT_LIST_HEAD(&rdev->slist);
2616         BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
2617
2618         /* preform any regulator specific init */
2619         if (init_data->regulator_init) {
2620                 ret = init_data->regulator_init(rdev->reg_data);
2621                 if (ret < 0)
2622                         goto clean;
2623         }
2624
2625         /* register with sysfs */
2626         rdev->dev.class = &regulator_class;
2627         rdev->dev.parent = dev;
2628         dev_set_name(&rdev->dev, "regulator.%d",
2629                      atomic_inc_return(&regulator_no) - 1);
2630         ret = device_register(&rdev->dev);
2631         if (ret != 0) {
2632                 put_device(&rdev->dev);
2633                 goto clean;
2634         }
2635
2636         dev_set_drvdata(&rdev->dev, rdev);
2637
2638         /* set regulator constraints */
2639         ret = set_machine_constraints(rdev, &init_data->constraints);
2640         if (ret < 0)
2641                 goto scrub;
2642
2643         /* add attributes supported by this regulator */
2644         ret = add_regulator_attributes(rdev);
2645         if (ret < 0)
2646                 goto scrub;
2647
2648         if (init_data->supply_regulator) {
2649                 struct regulator_dev *r;
2650                 int found = 0;
2651
2652                 list_for_each_entry(r, &regulator_list, list) {
2653                         if (strcmp(rdev_get_name(r),
2654                                    init_data->supply_regulator) == 0) {
2655                                 found = 1;
2656                                 break;
2657                         }
2658                 }
2659
2660                 if (!found) {
2661                         dev_err(dev, "Failed to find supply %s\n",
2662                                 init_data->supply_regulator);
2663                         ret = -ENODEV;
2664                         goto scrub;
2665                 }
2666
2667                 ret = set_supply(rdev, r);
2668                 if (ret < 0)
2669                         goto scrub;
2670         }
2671
2672         /* add consumers devices */
2673         for (i = 0; i < init_data->num_consumer_supplies; i++) {
2674                 ret = set_consumer_device_supply(rdev,
2675                         init_data->consumer_supplies[i].dev,
2676                         init_data->consumer_supplies[i].dev_name,
2677                         init_data->consumer_supplies[i].supply);
2678                 if (ret < 0) {
2679                         dev_err(dev, "Failed to set supply %s\n",
2680                                 init_data->consumer_supplies[i].supply);
2681                         goto unset_supplies;
2682                 }
2683         }
2684
2685         list_add(&rdev->list, &regulator_list);
2686
2687         rdev_init_debugfs(rdev);
2688 out:
2689         mutex_unlock(&regulator_list_mutex);
2690         return rdev;
2691
2692 unset_supplies:
2693         unset_regulator_supplies(rdev);
2694
2695 scrub:
2696         device_unregister(&rdev->dev);
2697         /* device core frees rdev */
2698         rdev = ERR_PTR(ret);
2699         goto out;
2700
2701 clean:
2702         kfree(rdev);
2703         rdev = ERR_PTR(ret);
2704         goto out;
2705 }
2706 EXPORT_SYMBOL_GPL(regulator_register);
2707
2708 /**
2709  * regulator_unregister - unregister regulator
2710  * @rdev: regulator to unregister
2711  *
2712  * Called by regulator drivers to unregister a regulator.
2713  */
2714 void regulator_unregister(struct regulator_dev *rdev)
2715 {
2716         if (rdev == NULL)
2717                 return;
2718
2719         mutex_lock(&regulator_list_mutex);
2720 #ifdef CONFIG_DEBUG_FS
2721         debugfs_remove_recursive(rdev->debugfs);
2722 #endif
2723         WARN_ON(rdev->open_count);
2724         unset_regulator_supplies(rdev);
2725         list_del(&rdev->list);
2726         if (rdev->supply)
2727                 sysfs_remove_link(&rdev->dev.kobj, "supply");
2728         device_unregister(&rdev->dev);
2729         kfree(rdev->constraints);
2730         mutex_unlock(&regulator_list_mutex);
2731 }
2732 EXPORT_SYMBOL_GPL(regulator_unregister);
2733
2734 /**
2735  * regulator_suspend_prepare - prepare regulators for system wide suspend
2736  * @state: system suspend state
2737  *
2738  * Configure each regulator with it's suspend operating parameters for state.
2739  * This will usually be called by machine suspend code prior to supending.
2740  */
2741 int regulator_suspend_prepare(suspend_state_t state)
2742 {
2743         struct regulator_dev *rdev;
2744         int ret = 0;
2745
2746         /* ON is handled by regulator active state */
2747         if (state == PM_SUSPEND_ON)
2748                 return -EINVAL;
2749
2750         mutex_lock(&regulator_list_mutex);
2751         list_for_each_entry(rdev, &regulator_list, list) {
2752
2753                 mutex_lock(&rdev->mutex);
2754                 ret = suspend_prepare(rdev, state);
2755                 mutex_unlock(&rdev->mutex);
2756
2757                 if (ret < 0) {
2758                         rdev_err(rdev, "failed to prepare\n");
2759                         goto out;
2760                 }
2761         }
2762 out:
2763         mutex_unlock(&regulator_list_mutex);
2764         return ret;
2765 }
2766 EXPORT_SYMBOL_GPL(regulator_suspend_prepare);
2767
2768 /**
2769  * regulator_suspend_finish - resume regulators from system wide suspend
2770  *
2771  * Turn on regulators that might be turned off by regulator_suspend_prepare
2772  * and that should be turned on according to the regulators properties.
2773  */
2774 int regulator_suspend_finish(void)
2775 {
2776         struct regulator_dev *rdev;
2777         int ret = 0, error;
2778
2779         mutex_lock(&regulator_list_mutex);
2780         list_for_each_entry(rdev, &regulator_list, list) {
2781                 struct regulator_ops *ops = rdev->desc->ops;
2782
2783                 mutex_lock(&rdev->mutex);
2784                 if ((rdev->use_count > 0  || rdev->constraints->always_on) &&
2785                                 ops->enable) {
2786                         error = ops->enable(rdev);
2787                         if (error)
2788                                 ret = error;
2789                 } else {
2790                         if (!has_full_constraints)
2791                                 goto unlock;
2792                         if (!ops->disable)
2793                                 goto unlock;
2794                         if (ops->is_enabled && !ops->is_enabled(rdev))
2795                                 goto unlock;
2796
2797                         error = ops->disable(rdev);
2798                         if (error)
2799                                 ret = error;
2800                 }
2801 unlock:
2802                 mutex_unlock(&rdev->mutex);
2803         }
2804         mutex_unlock(&regulator_list_mutex);
2805         return ret;
2806 }
2807 EXPORT_SYMBOL_GPL(regulator_suspend_finish);
2808
2809 /**
2810  * regulator_has_full_constraints - the system has fully specified constraints
2811  *
2812  * Calling this function will cause the regulator API to disable all
2813  * regulators which have a zero use count and don't have an always_on
2814  * constraint in a late_initcall.
2815  *
2816  * The intention is that this will become the default behaviour in a
2817  * future kernel release so users are encouraged to use this facility
2818  * now.
2819  */
2820 void regulator_has_full_constraints(void)
2821 {
2822         has_full_constraints = 1;
2823 }
2824 EXPORT_SYMBOL_GPL(regulator_has_full_constraints);
2825
2826 /**
2827  * regulator_use_dummy_regulator - Provide a dummy regulator when none is found
2828  *
2829  * Calling this function will cause the regulator API to provide a
2830  * dummy regulator to consumers if no physical regulator is found,
2831  * allowing most consumers to proceed as though a regulator were
2832  * configured.  This allows systems such as those with software
2833  * controllable regulators for the CPU core only to be brought up more
2834  * readily.
2835  */
2836 void regulator_use_dummy_regulator(void)
2837 {
2838         board_wants_dummy_regulator = true;
2839 }
2840 EXPORT_SYMBOL_GPL(regulator_use_dummy_regulator);
2841
2842 /**
2843  * rdev_get_drvdata - get rdev regulator driver data
2844  * @rdev: regulator
2845  *
2846  * Get rdev regulator driver private data. This call can be used in the
2847  * regulator driver context.
2848  */
2849 void *rdev_get_drvdata(struct regulator_dev *rdev)
2850 {
2851         return rdev->reg_data;
2852 }
2853 EXPORT_SYMBOL_GPL(rdev_get_drvdata);
2854
2855 /**
2856  * regulator_get_drvdata - get regulator driver data
2857  * @regulator: regulator
2858  *
2859  * Get regulator driver private data. This call can be used in the consumer
2860  * driver context when non API regulator specific functions need to be called.
2861  */
2862 void *regulator_get_drvdata(struct regulator *regulator)
2863 {
2864         return regulator->rdev->reg_data;
2865 }
2866 EXPORT_SYMBOL_GPL(regulator_get_drvdata);
2867
2868 /**
2869  * regulator_set_drvdata - set regulator driver data
2870  * @regulator: regulator
2871  * @data: data
2872  */
2873 void regulator_set_drvdata(struct regulator *regulator, void *data)
2874 {
2875         regulator->rdev->reg_data = data;
2876 }
2877 EXPORT_SYMBOL_GPL(regulator_set_drvdata);
2878
2879 /**
2880  * regulator_get_id - get regulator ID
2881  * @rdev: regulator
2882  */
2883 int rdev_get_id(struct regulator_dev *rdev)
2884 {
2885         return rdev->desc->id;
2886 }
2887 EXPORT_SYMBOL_GPL(rdev_get_id);
2888
2889 struct device *rdev_get_dev(struct regulator_dev *rdev)
2890 {
2891         return &rdev->dev;
2892 }
2893 EXPORT_SYMBOL_GPL(rdev_get_dev);
2894
2895 void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
2896 {
2897         return reg_init_data->driver_data;
2898 }
2899 EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
2900
2901 static int __init regulator_init(void)
2902 {
2903         int ret;
2904
2905         ret = class_register(&regulator_class);
2906
2907 #ifdef CONFIG_DEBUG_FS
2908         debugfs_root = debugfs_create_dir("regulator", NULL);
2909         if (IS_ERR(debugfs_root) || !debugfs_root) {
2910                 pr_warn("regulator: Failed to create debugfs directory\n");
2911                 debugfs_root = NULL;
2912         }
2913 #endif
2914
2915         regulator_dummy_init();
2916
2917         return ret;
2918 }
2919
2920 /* init early to allow our consumers to complete system booting */
2921 core_initcall(regulator_init);
2922
2923 static int __init regulator_init_complete(void)
2924 {
2925         struct regulator_dev *rdev;
2926         struct regulator_ops *ops;
2927         struct regulation_constraints *c;
2928         int enabled, ret;
2929
2930         mutex_lock(&regulator_list_mutex);
2931
2932         /* If we have a full configuration then disable any regulators
2933          * which are not in use or always_on.  This will become the
2934          * default behaviour in the future.
2935          */
2936         list_for_each_entry(rdev, &regulator_list, list) {
2937                 ops = rdev->desc->ops;
2938                 c = rdev->constraints;
2939
2940                 if (!ops->disable || (c && c->always_on))
2941                         continue;
2942
2943                 mutex_lock(&rdev->mutex);
2944
2945                 if (rdev->use_count)
2946                         goto unlock;
2947
2948                 /* If we can't read the status assume it's on. */
2949                 if (ops->is_enabled)
2950                         enabled = ops->is_enabled(rdev);
2951                 else
2952                         enabled = 1;
2953
2954                 if (!enabled)
2955                         goto unlock;
2956
2957                 if (has_full_constraints) {
2958                         /* We log since this may kill the system if it
2959                          * goes wrong. */
2960                         rdev_info(rdev, "disabling\n");
2961                         ret = ops->disable(rdev);
2962                         if (ret != 0) {
2963                                 rdev_err(rdev, "couldn't disable: %d\n", ret);
2964                         }
2965                 } else {
2966                         /* The intention is that in future we will
2967                          * assume that full constraints are provided
2968                          * so warn even if we aren't going to do
2969                          * anything here.
2970                          */
2971                         rdev_warn(rdev, "incomplete constraints, leaving on\n");
2972                 }
2973
2974 unlock:
2975                 mutex_unlock(&rdev->mutex);
2976         }
2977
2978         mutex_unlock(&regulator_list_mutex);
2979
2980         return 0;
2981 }
2982 late_initcall(regulator_init_complete);