Merge branch 'for-3.14-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj...
[profile/ivi/kernel-x86-ivi.git] / drivers / regulator / core.c
1 /*
2  * core.c  --  Voltage/Current Regulator framework.
3  *
4  * Copyright 2007, 2008 Wolfson Microelectronics PLC.
5  * Copyright 2008 SlimLogic Ltd.
6  *
7  * Author: Liam Girdwood <lrg@slimlogic.co.uk>
8  *
9  *  This program is free software; you can redistribute  it and/or modify it
10  *  under  the terms of  the GNU General  Public License as published by the
11  *  Free Software Foundation;  either version 2 of the  License, or (at your
12  *  option) any later version.
13  *
14  */
15
16 #include <linux/kernel.h>
17 #include <linux/init.h>
18 #include <linux/debugfs.h>
19 #include <linux/device.h>
20 #include <linux/slab.h>
21 #include <linux/async.h>
22 #include <linux/err.h>
23 #include <linux/mutex.h>
24 #include <linux/suspend.h>
25 #include <linux/delay.h>
26 #include <linux/gpio.h>
27 #include <linux/of.h>
28 #include <linux/regmap.h>
29 #include <linux/regulator/of_regulator.h>
30 #include <linux/regulator/consumer.h>
31 #include <linux/regulator/driver.h>
32 #include <linux/regulator/machine.h>
33 #include <linux/module.h>
34
35 #define CREATE_TRACE_POINTS
36 #include <trace/events/regulator.h>
37
38 #include "dummy.h"
39 #include "internal.h"
40
41 #define rdev_crit(rdev, fmt, ...)                                       \
42         pr_crit("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
43 #define rdev_err(rdev, fmt, ...)                                        \
44         pr_err("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
45 #define rdev_warn(rdev, fmt, ...)                                       \
46         pr_warn("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
47 #define rdev_info(rdev, fmt, ...)                                       \
48         pr_info("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
49 #define rdev_dbg(rdev, fmt, ...)                                        \
50         pr_debug("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
51
52 static DEFINE_MUTEX(regulator_list_mutex);
53 static LIST_HEAD(regulator_list);
54 static LIST_HEAD(regulator_map_list);
55 static LIST_HEAD(regulator_ena_gpio_list);
56 static LIST_HEAD(regulator_supply_alias_list);
57 static bool has_full_constraints;
58
59 static struct dentry *debugfs_root;
60
61 /*
62  * struct regulator_map
63  *
64  * Used to provide symbolic supply names to devices.
65  */
66 struct regulator_map {
67         struct list_head list;
68         const char *dev_name;   /* The dev_name() for the consumer */
69         const char *supply;
70         struct regulator_dev *regulator;
71 };
72
73 /*
74  * struct regulator_enable_gpio
75  *
76  * Management for shared enable GPIO pin
77  */
78 struct regulator_enable_gpio {
79         struct list_head list;
80         int gpio;
81         u32 enable_count;       /* a number of enabled shared GPIO */
82         u32 request_count;      /* a number of requested shared GPIO */
83         unsigned int ena_gpio_invert:1;
84 };
85
86 /*
87  * struct regulator_supply_alias
88  *
89  * Used to map lookups for a supply onto an alternative device.
90  */
91 struct regulator_supply_alias {
92         struct list_head list;
93         struct device *src_dev;
94         const char *src_supply;
95         struct device *alias_dev;
96         const char *alias_supply;
97 };
98
99 static int _regulator_is_enabled(struct regulator_dev *rdev);
100 static int _regulator_disable(struct regulator_dev *rdev);
101 static int _regulator_get_voltage(struct regulator_dev *rdev);
102 static int _regulator_get_current_limit(struct regulator_dev *rdev);
103 static unsigned int _regulator_get_mode(struct regulator_dev *rdev);
104 static void _notifier_call_chain(struct regulator_dev *rdev,
105                                   unsigned long event, void *data);
106 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
107                                      int min_uV, int max_uV);
108 static struct regulator *create_regulator(struct regulator_dev *rdev,
109                                           struct device *dev,
110                                           const char *supply_name);
111
112 static const char *rdev_get_name(struct regulator_dev *rdev)
113 {
114         if (rdev->constraints && rdev->constraints->name)
115                 return rdev->constraints->name;
116         else if (rdev->desc->name)
117                 return rdev->desc->name;
118         else
119                 return "";
120 }
121
122 static bool have_full_constraints(void)
123 {
124         return has_full_constraints || of_have_populated_dt();
125 }
126
127 /**
128  * of_get_regulator - get a regulator device node based on supply name
129  * @dev: Device pointer for the consumer (of regulator) device
130  * @supply: regulator supply name
131  *
132  * Extract the regulator device node corresponding to the supply name.
133  * returns the device node corresponding to the regulator if found, else
134  * returns NULL.
135  */
136 static struct device_node *of_get_regulator(struct device *dev, const char *supply)
137 {
138         struct device_node *regnode = NULL;
139         char prop_name[32]; /* 32 is max size of property name */
140
141         dev_dbg(dev, "Looking up %s-supply from device tree\n", supply);
142
143         snprintf(prop_name, 32, "%s-supply", supply);
144         regnode = of_parse_phandle(dev->of_node, prop_name, 0);
145
146         if (!regnode) {
147                 dev_dbg(dev, "Looking up %s property in node %s failed",
148                                 prop_name, dev->of_node->full_name);
149                 return NULL;
150         }
151         return regnode;
152 }
153
154 static int _regulator_can_change_status(struct regulator_dev *rdev)
155 {
156         if (!rdev->constraints)
157                 return 0;
158
159         if (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_STATUS)
160                 return 1;
161         else
162                 return 0;
163 }
164
165 /* Platform voltage constraint check */
166 static int regulator_check_voltage(struct regulator_dev *rdev,
167                                    int *min_uV, int *max_uV)
168 {
169         BUG_ON(*min_uV > *max_uV);
170
171         if (!rdev->constraints) {
172                 rdev_err(rdev, "no constraints\n");
173                 return -ENODEV;
174         }
175         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
176                 rdev_err(rdev, "operation not allowed\n");
177                 return -EPERM;
178         }
179
180         if (*max_uV > rdev->constraints->max_uV)
181                 *max_uV = rdev->constraints->max_uV;
182         if (*min_uV < rdev->constraints->min_uV)
183                 *min_uV = rdev->constraints->min_uV;
184
185         if (*min_uV > *max_uV) {
186                 rdev_err(rdev, "unsupportable voltage range: %d-%duV\n",
187                          *min_uV, *max_uV);
188                 return -EINVAL;
189         }
190
191         return 0;
192 }
193
194 /* Make sure we select a voltage that suits the needs of all
195  * regulator consumers
196  */
197 static int regulator_check_consumers(struct regulator_dev *rdev,
198                                      int *min_uV, int *max_uV)
199 {
200         struct regulator *regulator;
201
202         list_for_each_entry(regulator, &rdev->consumer_list, list) {
203                 /*
204                  * Assume consumers that didn't say anything are OK
205                  * with anything in the constraint range.
206                  */
207                 if (!regulator->min_uV && !regulator->max_uV)
208                         continue;
209
210                 if (*max_uV > regulator->max_uV)
211                         *max_uV = regulator->max_uV;
212                 if (*min_uV < regulator->min_uV)
213                         *min_uV = regulator->min_uV;
214         }
215
216         if (*min_uV > *max_uV) {
217                 rdev_err(rdev, "Restricting voltage, %u-%uuV\n",
218                         *min_uV, *max_uV);
219                 return -EINVAL;
220         }
221
222         return 0;
223 }
224
225 /* current constraint check */
226 static int regulator_check_current_limit(struct regulator_dev *rdev,
227                                         int *min_uA, int *max_uA)
228 {
229         BUG_ON(*min_uA > *max_uA);
230
231         if (!rdev->constraints) {
232                 rdev_err(rdev, "no constraints\n");
233                 return -ENODEV;
234         }
235         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_CURRENT)) {
236                 rdev_err(rdev, "operation not allowed\n");
237                 return -EPERM;
238         }
239
240         if (*max_uA > rdev->constraints->max_uA)
241                 *max_uA = rdev->constraints->max_uA;
242         if (*min_uA < rdev->constraints->min_uA)
243                 *min_uA = rdev->constraints->min_uA;
244
245         if (*min_uA > *max_uA) {
246                 rdev_err(rdev, "unsupportable current range: %d-%duA\n",
247                          *min_uA, *max_uA);
248                 return -EINVAL;
249         }
250
251         return 0;
252 }
253
254 /* operating mode constraint check */
255 static int regulator_mode_constrain(struct regulator_dev *rdev, int *mode)
256 {
257         switch (*mode) {
258         case REGULATOR_MODE_FAST:
259         case REGULATOR_MODE_NORMAL:
260         case REGULATOR_MODE_IDLE:
261         case REGULATOR_MODE_STANDBY:
262                 break;
263         default:
264                 rdev_err(rdev, "invalid mode %x specified\n", *mode);
265                 return -EINVAL;
266         }
267
268         if (!rdev->constraints) {
269                 rdev_err(rdev, "no constraints\n");
270                 return -ENODEV;
271         }
272         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_MODE)) {
273                 rdev_err(rdev, "operation not allowed\n");
274                 return -EPERM;
275         }
276
277         /* The modes are bitmasks, the most power hungry modes having
278          * the lowest values. If the requested mode isn't supported
279          * try higher modes. */
280         while (*mode) {
281                 if (rdev->constraints->valid_modes_mask & *mode)
282                         return 0;
283                 *mode /= 2;
284         }
285
286         return -EINVAL;
287 }
288
289 /* dynamic regulator mode switching constraint check */
290 static int regulator_check_drms(struct regulator_dev *rdev)
291 {
292         if (!rdev->constraints) {
293                 rdev_err(rdev, "no constraints\n");
294                 return -ENODEV;
295         }
296         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS)) {
297                 rdev_err(rdev, "operation not allowed\n");
298                 return -EPERM;
299         }
300         return 0;
301 }
302
303 static ssize_t regulator_uV_show(struct device *dev,
304                                 struct device_attribute *attr, char *buf)
305 {
306         struct regulator_dev *rdev = dev_get_drvdata(dev);
307         ssize_t ret;
308
309         mutex_lock(&rdev->mutex);
310         ret = sprintf(buf, "%d\n", _regulator_get_voltage(rdev));
311         mutex_unlock(&rdev->mutex);
312
313         return ret;
314 }
315 static DEVICE_ATTR(microvolts, 0444, regulator_uV_show, NULL);
316
317 static ssize_t regulator_uA_show(struct device *dev,
318                                 struct device_attribute *attr, char *buf)
319 {
320         struct regulator_dev *rdev = dev_get_drvdata(dev);
321
322         return sprintf(buf, "%d\n", _regulator_get_current_limit(rdev));
323 }
324 static DEVICE_ATTR(microamps, 0444, regulator_uA_show, NULL);
325
326 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
327                          char *buf)
328 {
329         struct regulator_dev *rdev = dev_get_drvdata(dev);
330
331         return sprintf(buf, "%s\n", rdev_get_name(rdev));
332 }
333 static DEVICE_ATTR_RO(name);
334
335 static ssize_t regulator_print_opmode(char *buf, int mode)
336 {
337         switch (mode) {
338         case REGULATOR_MODE_FAST:
339                 return sprintf(buf, "fast\n");
340         case REGULATOR_MODE_NORMAL:
341                 return sprintf(buf, "normal\n");
342         case REGULATOR_MODE_IDLE:
343                 return sprintf(buf, "idle\n");
344         case REGULATOR_MODE_STANDBY:
345                 return sprintf(buf, "standby\n");
346         }
347         return sprintf(buf, "unknown\n");
348 }
349
350 static ssize_t regulator_opmode_show(struct device *dev,
351                                     struct device_attribute *attr, char *buf)
352 {
353         struct regulator_dev *rdev = dev_get_drvdata(dev);
354
355         return regulator_print_opmode(buf, _regulator_get_mode(rdev));
356 }
357 static DEVICE_ATTR(opmode, 0444, regulator_opmode_show, NULL);
358
359 static ssize_t regulator_print_state(char *buf, int state)
360 {
361         if (state > 0)
362                 return sprintf(buf, "enabled\n");
363         else if (state == 0)
364                 return sprintf(buf, "disabled\n");
365         else
366                 return sprintf(buf, "unknown\n");
367 }
368
369 static ssize_t regulator_state_show(struct device *dev,
370                                    struct device_attribute *attr, char *buf)
371 {
372         struct regulator_dev *rdev = dev_get_drvdata(dev);
373         ssize_t ret;
374
375         mutex_lock(&rdev->mutex);
376         ret = regulator_print_state(buf, _regulator_is_enabled(rdev));
377         mutex_unlock(&rdev->mutex);
378
379         return ret;
380 }
381 static DEVICE_ATTR(state, 0444, regulator_state_show, NULL);
382
383 static ssize_t regulator_status_show(struct device *dev,
384                                    struct device_attribute *attr, char *buf)
385 {
386         struct regulator_dev *rdev = dev_get_drvdata(dev);
387         int status;
388         char *label;
389
390         status = rdev->desc->ops->get_status(rdev);
391         if (status < 0)
392                 return status;
393
394         switch (status) {
395         case REGULATOR_STATUS_OFF:
396                 label = "off";
397                 break;
398         case REGULATOR_STATUS_ON:
399                 label = "on";
400                 break;
401         case REGULATOR_STATUS_ERROR:
402                 label = "error";
403                 break;
404         case REGULATOR_STATUS_FAST:
405                 label = "fast";
406                 break;
407         case REGULATOR_STATUS_NORMAL:
408                 label = "normal";
409                 break;
410         case REGULATOR_STATUS_IDLE:
411                 label = "idle";
412                 break;
413         case REGULATOR_STATUS_STANDBY:
414                 label = "standby";
415                 break;
416         case REGULATOR_STATUS_BYPASS:
417                 label = "bypass";
418                 break;
419         case REGULATOR_STATUS_UNDEFINED:
420                 label = "undefined";
421                 break;
422         default:
423                 return -ERANGE;
424         }
425
426         return sprintf(buf, "%s\n", label);
427 }
428 static DEVICE_ATTR(status, 0444, regulator_status_show, NULL);
429
430 static ssize_t regulator_min_uA_show(struct device *dev,
431                                     struct device_attribute *attr, char *buf)
432 {
433         struct regulator_dev *rdev = dev_get_drvdata(dev);
434
435         if (!rdev->constraints)
436                 return sprintf(buf, "constraint not defined\n");
437
438         return sprintf(buf, "%d\n", rdev->constraints->min_uA);
439 }
440 static DEVICE_ATTR(min_microamps, 0444, regulator_min_uA_show, NULL);
441
442 static ssize_t regulator_max_uA_show(struct device *dev,
443                                     struct device_attribute *attr, char *buf)
444 {
445         struct regulator_dev *rdev = dev_get_drvdata(dev);
446
447         if (!rdev->constraints)
448                 return sprintf(buf, "constraint not defined\n");
449
450         return sprintf(buf, "%d\n", rdev->constraints->max_uA);
451 }
452 static DEVICE_ATTR(max_microamps, 0444, regulator_max_uA_show, NULL);
453
454 static ssize_t regulator_min_uV_show(struct device *dev,
455                                     struct device_attribute *attr, char *buf)
456 {
457         struct regulator_dev *rdev = dev_get_drvdata(dev);
458
459         if (!rdev->constraints)
460                 return sprintf(buf, "constraint not defined\n");
461
462         return sprintf(buf, "%d\n", rdev->constraints->min_uV);
463 }
464 static DEVICE_ATTR(min_microvolts, 0444, regulator_min_uV_show, NULL);
465
466 static ssize_t regulator_max_uV_show(struct device *dev,
467                                     struct device_attribute *attr, char *buf)
468 {
469         struct regulator_dev *rdev = dev_get_drvdata(dev);
470
471         if (!rdev->constraints)
472                 return sprintf(buf, "constraint not defined\n");
473
474         return sprintf(buf, "%d\n", rdev->constraints->max_uV);
475 }
476 static DEVICE_ATTR(max_microvolts, 0444, regulator_max_uV_show, NULL);
477
478 static ssize_t regulator_total_uA_show(struct device *dev,
479                                       struct device_attribute *attr, char *buf)
480 {
481         struct regulator_dev *rdev = dev_get_drvdata(dev);
482         struct regulator *regulator;
483         int uA = 0;
484
485         mutex_lock(&rdev->mutex);
486         list_for_each_entry(regulator, &rdev->consumer_list, list)
487                 uA += regulator->uA_load;
488         mutex_unlock(&rdev->mutex);
489         return sprintf(buf, "%d\n", uA);
490 }
491 static DEVICE_ATTR(requested_microamps, 0444, regulator_total_uA_show, NULL);
492
493 static ssize_t num_users_show(struct device *dev, struct device_attribute *attr,
494                               char *buf)
495 {
496         struct regulator_dev *rdev = dev_get_drvdata(dev);
497         return sprintf(buf, "%d\n", rdev->use_count);
498 }
499 static DEVICE_ATTR_RO(num_users);
500
501 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
502                          char *buf)
503 {
504         struct regulator_dev *rdev = dev_get_drvdata(dev);
505
506         switch (rdev->desc->type) {
507         case REGULATOR_VOLTAGE:
508                 return sprintf(buf, "voltage\n");
509         case REGULATOR_CURRENT:
510                 return sprintf(buf, "current\n");
511         }
512         return sprintf(buf, "unknown\n");
513 }
514 static DEVICE_ATTR_RO(type);
515
516 static ssize_t regulator_suspend_mem_uV_show(struct device *dev,
517                                 struct device_attribute *attr, char *buf)
518 {
519         struct regulator_dev *rdev = dev_get_drvdata(dev);
520
521         return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
522 }
523 static DEVICE_ATTR(suspend_mem_microvolts, 0444,
524                 regulator_suspend_mem_uV_show, NULL);
525
526 static ssize_t regulator_suspend_disk_uV_show(struct device *dev,
527                                 struct device_attribute *attr, char *buf)
528 {
529         struct regulator_dev *rdev = dev_get_drvdata(dev);
530
531         return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
532 }
533 static DEVICE_ATTR(suspend_disk_microvolts, 0444,
534                 regulator_suspend_disk_uV_show, NULL);
535
536 static ssize_t regulator_suspend_standby_uV_show(struct device *dev,
537                                 struct device_attribute *attr, char *buf)
538 {
539         struct regulator_dev *rdev = dev_get_drvdata(dev);
540
541         return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
542 }
543 static DEVICE_ATTR(suspend_standby_microvolts, 0444,
544                 regulator_suspend_standby_uV_show, NULL);
545
546 static ssize_t regulator_suspend_mem_mode_show(struct device *dev,
547                                 struct device_attribute *attr, char *buf)
548 {
549         struct regulator_dev *rdev = dev_get_drvdata(dev);
550
551         return regulator_print_opmode(buf,
552                 rdev->constraints->state_mem.mode);
553 }
554 static DEVICE_ATTR(suspend_mem_mode, 0444,
555                 regulator_suspend_mem_mode_show, NULL);
556
557 static ssize_t regulator_suspend_disk_mode_show(struct device *dev,
558                                 struct device_attribute *attr, char *buf)
559 {
560         struct regulator_dev *rdev = dev_get_drvdata(dev);
561
562         return regulator_print_opmode(buf,
563                 rdev->constraints->state_disk.mode);
564 }
565 static DEVICE_ATTR(suspend_disk_mode, 0444,
566                 regulator_suspend_disk_mode_show, NULL);
567
568 static ssize_t regulator_suspend_standby_mode_show(struct device *dev,
569                                 struct device_attribute *attr, char *buf)
570 {
571         struct regulator_dev *rdev = dev_get_drvdata(dev);
572
573         return regulator_print_opmode(buf,
574                 rdev->constraints->state_standby.mode);
575 }
576 static DEVICE_ATTR(suspend_standby_mode, 0444,
577                 regulator_suspend_standby_mode_show, NULL);
578
579 static ssize_t regulator_suspend_mem_state_show(struct device *dev,
580                                    struct device_attribute *attr, char *buf)
581 {
582         struct regulator_dev *rdev = dev_get_drvdata(dev);
583
584         return regulator_print_state(buf,
585                         rdev->constraints->state_mem.enabled);
586 }
587 static DEVICE_ATTR(suspend_mem_state, 0444,
588                 regulator_suspend_mem_state_show, NULL);
589
590 static ssize_t regulator_suspend_disk_state_show(struct device *dev,
591                                    struct device_attribute *attr, char *buf)
592 {
593         struct regulator_dev *rdev = dev_get_drvdata(dev);
594
595         return regulator_print_state(buf,
596                         rdev->constraints->state_disk.enabled);
597 }
598 static DEVICE_ATTR(suspend_disk_state, 0444,
599                 regulator_suspend_disk_state_show, NULL);
600
601 static ssize_t regulator_suspend_standby_state_show(struct device *dev,
602                                    struct device_attribute *attr, char *buf)
603 {
604         struct regulator_dev *rdev = dev_get_drvdata(dev);
605
606         return regulator_print_state(buf,
607                         rdev->constraints->state_standby.enabled);
608 }
609 static DEVICE_ATTR(suspend_standby_state, 0444,
610                 regulator_suspend_standby_state_show, NULL);
611
612 static ssize_t regulator_bypass_show(struct device *dev,
613                                      struct device_attribute *attr, char *buf)
614 {
615         struct regulator_dev *rdev = dev_get_drvdata(dev);
616         const char *report;
617         bool bypass;
618         int ret;
619
620         ret = rdev->desc->ops->get_bypass(rdev, &bypass);
621
622         if (ret != 0)
623                 report = "unknown";
624         else if (bypass)
625                 report = "enabled";
626         else
627                 report = "disabled";
628
629         return sprintf(buf, "%s\n", report);
630 }
631 static DEVICE_ATTR(bypass, 0444,
632                    regulator_bypass_show, NULL);
633
634 /*
635  * These are the only attributes are present for all regulators.
636  * Other attributes are a function of regulator functionality.
637  */
638 static struct attribute *regulator_dev_attrs[] = {
639         &dev_attr_name.attr,
640         &dev_attr_num_users.attr,
641         &dev_attr_type.attr,
642         NULL,
643 };
644 ATTRIBUTE_GROUPS(regulator_dev);
645
646 static void regulator_dev_release(struct device *dev)
647 {
648         struct regulator_dev *rdev = dev_get_drvdata(dev);
649         kfree(rdev);
650 }
651
652 static struct class regulator_class = {
653         .name = "regulator",
654         .dev_release = regulator_dev_release,
655         .dev_groups = regulator_dev_groups,
656 };
657
658 /* Calculate the new optimum regulator operating mode based on the new total
659  * consumer load. All locks held by caller */
660 static void drms_uA_update(struct regulator_dev *rdev)
661 {
662         struct regulator *sibling;
663         int current_uA = 0, output_uV, input_uV, err;
664         unsigned int mode;
665
666         err = regulator_check_drms(rdev);
667         if (err < 0 || !rdev->desc->ops->get_optimum_mode ||
668             (!rdev->desc->ops->get_voltage &&
669              !rdev->desc->ops->get_voltage_sel) ||
670             !rdev->desc->ops->set_mode)
671                 return;
672
673         /* get output voltage */
674         output_uV = _regulator_get_voltage(rdev);
675         if (output_uV <= 0)
676                 return;
677
678         /* get input voltage */
679         input_uV = 0;
680         if (rdev->supply)
681                 input_uV = regulator_get_voltage(rdev->supply);
682         if (input_uV <= 0)
683                 input_uV = rdev->constraints->input_uV;
684         if (input_uV <= 0)
685                 return;
686
687         /* calc total requested load */
688         list_for_each_entry(sibling, &rdev->consumer_list, list)
689                 current_uA += sibling->uA_load;
690
691         /* now get the optimum mode for our new total regulator load */
692         mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
693                                                   output_uV, current_uA);
694
695         /* check the new mode is allowed */
696         err = regulator_mode_constrain(rdev, &mode);
697         if (err == 0)
698                 rdev->desc->ops->set_mode(rdev, mode);
699 }
700
701 static int suspend_set_state(struct regulator_dev *rdev,
702         struct regulator_state *rstate)
703 {
704         int ret = 0;
705
706         /* If we have no suspend mode configration don't set anything;
707          * only warn if the driver implements set_suspend_voltage or
708          * set_suspend_mode callback.
709          */
710         if (!rstate->enabled && !rstate->disabled) {
711                 if (rdev->desc->ops->set_suspend_voltage ||
712                     rdev->desc->ops->set_suspend_mode)
713                         rdev_warn(rdev, "No configuration\n");
714                 return 0;
715         }
716
717         if (rstate->enabled && rstate->disabled) {
718                 rdev_err(rdev, "invalid configuration\n");
719                 return -EINVAL;
720         }
721
722         if (rstate->enabled && rdev->desc->ops->set_suspend_enable)
723                 ret = rdev->desc->ops->set_suspend_enable(rdev);
724         else if (rstate->disabled && rdev->desc->ops->set_suspend_disable)
725                 ret = rdev->desc->ops->set_suspend_disable(rdev);
726         else /* OK if set_suspend_enable or set_suspend_disable is NULL */
727                 ret = 0;
728
729         if (ret < 0) {
730                 rdev_err(rdev, "failed to enabled/disable\n");
731                 return ret;
732         }
733
734         if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
735                 ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
736                 if (ret < 0) {
737                         rdev_err(rdev, "failed to set voltage\n");
738                         return ret;
739                 }
740         }
741
742         if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
743                 ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
744                 if (ret < 0) {
745                         rdev_err(rdev, "failed to set mode\n");
746                         return ret;
747                 }
748         }
749         return ret;
750 }
751
752 /* locks held by caller */
753 static int suspend_prepare(struct regulator_dev *rdev, suspend_state_t state)
754 {
755         if (!rdev->constraints)
756                 return -EINVAL;
757
758         switch (state) {
759         case PM_SUSPEND_STANDBY:
760                 return suspend_set_state(rdev,
761                         &rdev->constraints->state_standby);
762         case PM_SUSPEND_MEM:
763                 return suspend_set_state(rdev,
764                         &rdev->constraints->state_mem);
765         case PM_SUSPEND_MAX:
766                 return suspend_set_state(rdev,
767                         &rdev->constraints->state_disk);
768         default:
769                 return -EINVAL;
770         }
771 }
772
773 static void print_constraints(struct regulator_dev *rdev)
774 {
775         struct regulation_constraints *constraints = rdev->constraints;
776         char buf[80] = "";
777         int count = 0;
778         int ret;
779
780         if (constraints->min_uV && constraints->max_uV) {
781                 if (constraints->min_uV == constraints->max_uV)
782                         count += sprintf(buf + count, "%d mV ",
783                                          constraints->min_uV / 1000);
784                 else
785                         count += sprintf(buf + count, "%d <--> %d mV ",
786                                          constraints->min_uV / 1000,
787                                          constraints->max_uV / 1000);
788         }
789
790         if (!constraints->min_uV ||
791             constraints->min_uV != constraints->max_uV) {
792                 ret = _regulator_get_voltage(rdev);
793                 if (ret > 0)
794                         count += sprintf(buf + count, "at %d mV ", ret / 1000);
795         }
796
797         if (constraints->uV_offset)
798                 count += sprintf(buf, "%dmV offset ",
799                                  constraints->uV_offset / 1000);
800
801         if (constraints->min_uA && constraints->max_uA) {
802                 if (constraints->min_uA == constraints->max_uA)
803                         count += sprintf(buf + count, "%d mA ",
804                                          constraints->min_uA / 1000);
805                 else
806                         count += sprintf(buf + count, "%d <--> %d mA ",
807                                          constraints->min_uA / 1000,
808                                          constraints->max_uA / 1000);
809         }
810
811         if (!constraints->min_uA ||
812             constraints->min_uA != constraints->max_uA) {
813                 ret = _regulator_get_current_limit(rdev);
814                 if (ret > 0)
815                         count += sprintf(buf + count, "at %d mA ", ret / 1000);
816         }
817
818         if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
819                 count += sprintf(buf + count, "fast ");
820         if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
821                 count += sprintf(buf + count, "normal ");
822         if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
823                 count += sprintf(buf + count, "idle ");
824         if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
825                 count += sprintf(buf + count, "standby");
826
827         if (!count)
828                 sprintf(buf, "no parameters");
829
830         rdev_info(rdev, "%s\n", buf);
831
832         if ((constraints->min_uV != constraints->max_uV) &&
833             !(constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE))
834                 rdev_warn(rdev,
835                           "Voltage range but no REGULATOR_CHANGE_VOLTAGE\n");
836 }
837
838 static int machine_constraints_voltage(struct regulator_dev *rdev,
839         struct regulation_constraints *constraints)
840 {
841         struct regulator_ops *ops = rdev->desc->ops;
842         int ret;
843
844         /* do we need to apply the constraint voltage */
845         if (rdev->constraints->apply_uV &&
846             rdev->constraints->min_uV == rdev->constraints->max_uV) {
847                 ret = _regulator_do_set_voltage(rdev,
848                                                 rdev->constraints->min_uV,
849                                                 rdev->constraints->max_uV);
850                 if (ret < 0) {
851                         rdev_err(rdev, "failed to apply %duV constraint\n",
852                                  rdev->constraints->min_uV);
853                         return ret;
854                 }
855         }
856
857         /* constrain machine-level voltage specs to fit
858          * the actual range supported by this regulator.
859          */
860         if (ops->list_voltage && rdev->desc->n_voltages) {
861                 int     count = rdev->desc->n_voltages;
862                 int     i;
863                 int     min_uV = INT_MAX;
864                 int     max_uV = INT_MIN;
865                 int     cmin = constraints->min_uV;
866                 int     cmax = constraints->max_uV;
867
868                 /* it's safe to autoconfigure fixed-voltage supplies
869                    and the constraints are used by list_voltage. */
870                 if (count == 1 && !cmin) {
871                         cmin = 1;
872                         cmax = INT_MAX;
873                         constraints->min_uV = cmin;
874                         constraints->max_uV = cmax;
875                 }
876
877                 /* voltage constraints are optional */
878                 if ((cmin == 0) && (cmax == 0))
879                         return 0;
880
881                 /* else require explicit machine-level constraints */
882                 if (cmin <= 0 || cmax <= 0 || cmax < cmin) {
883                         rdev_err(rdev, "invalid voltage constraints\n");
884                         return -EINVAL;
885                 }
886
887                 /* initial: [cmin..cmax] valid, [min_uV..max_uV] not */
888                 for (i = 0; i < count; i++) {
889                         int     value;
890
891                         value = ops->list_voltage(rdev, i);
892                         if (value <= 0)
893                                 continue;
894
895                         /* maybe adjust [min_uV..max_uV] */
896                         if (value >= cmin && value < min_uV)
897                                 min_uV = value;
898                         if (value <= cmax && value > max_uV)
899                                 max_uV = value;
900                 }
901
902                 /* final: [min_uV..max_uV] valid iff constraints valid */
903                 if (max_uV < min_uV) {
904                         rdev_err(rdev,
905                                  "unsupportable voltage constraints %u-%uuV\n",
906                                  min_uV, max_uV);
907                         return -EINVAL;
908                 }
909
910                 /* use regulator's subset of machine constraints */
911                 if (constraints->min_uV < min_uV) {
912                         rdev_dbg(rdev, "override min_uV, %d -> %d\n",
913                                  constraints->min_uV, min_uV);
914                         constraints->min_uV = min_uV;
915                 }
916                 if (constraints->max_uV > max_uV) {
917                         rdev_dbg(rdev, "override max_uV, %d -> %d\n",
918                                  constraints->max_uV, max_uV);
919                         constraints->max_uV = max_uV;
920                 }
921         }
922
923         return 0;
924 }
925
926 static int machine_constraints_current(struct regulator_dev *rdev,
927         struct regulation_constraints *constraints)
928 {
929         struct regulator_ops *ops = rdev->desc->ops;
930         int ret;
931
932         if (!constraints->min_uA && !constraints->max_uA)
933                 return 0;
934
935         if (constraints->min_uA > constraints->max_uA) {
936                 rdev_err(rdev, "Invalid current constraints\n");
937                 return -EINVAL;
938         }
939
940         if (!ops->set_current_limit || !ops->get_current_limit) {
941                 rdev_warn(rdev, "Operation of current configuration missing\n");
942                 return 0;
943         }
944
945         /* Set regulator current in constraints range */
946         ret = ops->set_current_limit(rdev, constraints->min_uA,
947                         constraints->max_uA);
948         if (ret < 0) {
949                 rdev_err(rdev, "Failed to set current constraint, %d\n", ret);
950                 return ret;
951         }
952
953         return 0;
954 }
955
956 /**
957  * set_machine_constraints - sets regulator constraints
958  * @rdev: regulator source
959  * @constraints: constraints to apply
960  *
961  * Allows platform initialisation code to define and constrain
962  * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
963  * Constraints *must* be set by platform code in order for some
964  * regulator operations to proceed i.e. set_voltage, set_current_limit,
965  * set_mode.
966  */
967 static int set_machine_constraints(struct regulator_dev *rdev,
968         const struct regulation_constraints *constraints)
969 {
970         int ret = 0;
971         struct regulator_ops *ops = rdev->desc->ops;
972
973         if (constraints)
974                 rdev->constraints = kmemdup(constraints, sizeof(*constraints),
975                                             GFP_KERNEL);
976         else
977                 rdev->constraints = kzalloc(sizeof(*constraints),
978                                             GFP_KERNEL);
979         if (!rdev->constraints)
980                 return -ENOMEM;
981
982         ret = machine_constraints_voltage(rdev, rdev->constraints);
983         if (ret != 0)
984                 goto out;
985
986         ret = machine_constraints_current(rdev, rdev->constraints);
987         if (ret != 0)
988                 goto out;
989
990         /* do we need to setup our suspend state */
991         if (rdev->constraints->initial_state) {
992                 ret = suspend_prepare(rdev, rdev->constraints->initial_state);
993                 if (ret < 0) {
994                         rdev_err(rdev, "failed to set suspend state\n");
995                         goto out;
996                 }
997         }
998
999         if (rdev->constraints->initial_mode) {
1000                 if (!ops->set_mode) {
1001                         rdev_err(rdev, "no set_mode operation\n");
1002                         ret = -EINVAL;
1003                         goto out;
1004                 }
1005
1006                 ret = ops->set_mode(rdev, rdev->constraints->initial_mode);
1007                 if (ret < 0) {
1008                         rdev_err(rdev, "failed to set initial mode: %d\n", ret);
1009                         goto out;
1010                 }
1011         }
1012
1013         /* If the constraints say the regulator should be on at this point
1014          * and we have control then make sure it is enabled.
1015          */
1016         if ((rdev->constraints->always_on || rdev->constraints->boot_on) &&
1017             ops->enable) {
1018                 ret = ops->enable(rdev);
1019                 if (ret < 0) {
1020                         rdev_err(rdev, "failed to enable\n");
1021                         goto out;
1022                 }
1023         }
1024
1025         if ((rdev->constraints->ramp_delay || rdev->constraints->ramp_disable)
1026                 && ops->set_ramp_delay) {
1027                 ret = ops->set_ramp_delay(rdev, rdev->constraints->ramp_delay);
1028                 if (ret < 0) {
1029                         rdev_err(rdev, "failed to set ramp_delay\n");
1030                         goto out;
1031                 }
1032         }
1033
1034         print_constraints(rdev);
1035         return 0;
1036 out:
1037         kfree(rdev->constraints);
1038         rdev->constraints = NULL;
1039         return ret;
1040 }
1041
1042 /**
1043  * set_supply - set regulator supply regulator
1044  * @rdev: regulator name
1045  * @supply_rdev: supply regulator name
1046  *
1047  * Called by platform initialisation code to set the supply regulator for this
1048  * regulator. This ensures that a regulators supply will also be enabled by the
1049  * core if it's child is enabled.
1050  */
1051 static int set_supply(struct regulator_dev *rdev,
1052                       struct regulator_dev *supply_rdev)
1053 {
1054         int err;
1055
1056         rdev_info(rdev, "supplied by %s\n", rdev_get_name(supply_rdev));
1057
1058         rdev->supply = create_regulator(supply_rdev, &rdev->dev, "SUPPLY");
1059         if (rdev->supply == NULL) {
1060                 err = -ENOMEM;
1061                 return err;
1062         }
1063         supply_rdev->open_count++;
1064
1065         return 0;
1066 }
1067
1068 /**
1069  * set_consumer_device_supply - Bind a regulator to a symbolic supply
1070  * @rdev:         regulator source
1071  * @consumer_dev_name: dev_name() string for device supply applies to
1072  * @supply:       symbolic name for supply
1073  *
1074  * Allows platform initialisation code to map physical regulator
1075  * sources to symbolic names for supplies for use by devices.  Devices
1076  * should use these symbolic names to request regulators, avoiding the
1077  * need to provide board-specific regulator names as platform data.
1078  */
1079 static int set_consumer_device_supply(struct regulator_dev *rdev,
1080                                       const char *consumer_dev_name,
1081                                       const char *supply)
1082 {
1083         struct regulator_map *node;
1084         int has_dev;
1085
1086         if (supply == NULL)
1087                 return -EINVAL;
1088
1089         if (consumer_dev_name != NULL)
1090                 has_dev = 1;
1091         else
1092                 has_dev = 0;
1093
1094         list_for_each_entry(node, &regulator_map_list, list) {
1095                 if (node->dev_name && consumer_dev_name) {
1096                         if (strcmp(node->dev_name, consumer_dev_name) != 0)
1097                                 continue;
1098                 } else if (node->dev_name || consumer_dev_name) {
1099                         continue;
1100                 }
1101
1102                 if (strcmp(node->supply, supply) != 0)
1103                         continue;
1104
1105                 pr_debug("%s: %s/%s is '%s' supply; fail %s/%s\n",
1106                          consumer_dev_name,
1107                          dev_name(&node->regulator->dev),
1108                          node->regulator->desc->name,
1109                          supply,
1110                          dev_name(&rdev->dev), rdev_get_name(rdev));
1111                 return -EBUSY;
1112         }
1113
1114         node = kzalloc(sizeof(struct regulator_map), GFP_KERNEL);
1115         if (node == NULL)
1116                 return -ENOMEM;
1117
1118         node->regulator = rdev;
1119         node->supply = supply;
1120
1121         if (has_dev) {
1122                 node->dev_name = kstrdup(consumer_dev_name, GFP_KERNEL);
1123                 if (node->dev_name == NULL) {
1124                         kfree(node);
1125                         return -ENOMEM;
1126                 }
1127         }
1128
1129         list_add(&node->list, &regulator_map_list);
1130         return 0;
1131 }
1132
1133 static void unset_regulator_supplies(struct regulator_dev *rdev)
1134 {
1135         struct regulator_map *node, *n;
1136
1137         list_for_each_entry_safe(node, n, &regulator_map_list, list) {
1138                 if (rdev == node->regulator) {
1139                         list_del(&node->list);
1140                         kfree(node->dev_name);
1141                         kfree(node);
1142                 }
1143         }
1144 }
1145
1146 #define REG_STR_SIZE    64
1147
1148 static struct regulator *create_regulator(struct regulator_dev *rdev,
1149                                           struct device *dev,
1150                                           const char *supply_name)
1151 {
1152         struct regulator *regulator;
1153         char buf[REG_STR_SIZE];
1154         int err, size;
1155
1156         regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
1157         if (regulator == NULL)
1158                 return NULL;
1159
1160         mutex_lock(&rdev->mutex);
1161         regulator->rdev = rdev;
1162         list_add(&regulator->list, &rdev->consumer_list);
1163
1164         if (dev) {
1165                 regulator->dev = dev;
1166
1167                 /* Add a link to the device sysfs entry */
1168                 size = scnprintf(buf, REG_STR_SIZE, "%s-%s",
1169                                  dev->kobj.name, supply_name);
1170                 if (size >= REG_STR_SIZE)
1171                         goto overflow_err;
1172
1173                 regulator->supply_name = kstrdup(buf, GFP_KERNEL);
1174                 if (regulator->supply_name == NULL)
1175                         goto overflow_err;
1176
1177                 err = sysfs_create_link(&rdev->dev.kobj, &dev->kobj,
1178                                         buf);
1179                 if (err) {
1180                         rdev_warn(rdev, "could not add device link %s err %d\n",
1181                                   dev->kobj.name, err);
1182                         /* non-fatal */
1183                 }
1184         } else {
1185                 regulator->supply_name = kstrdup(supply_name, GFP_KERNEL);
1186                 if (regulator->supply_name == NULL)
1187                         goto overflow_err;
1188         }
1189
1190         regulator->debugfs = debugfs_create_dir(regulator->supply_name,
1191                                                 rdev->debugfs);
1192         if (!regulator->debugfs) {
1193                 rdev_warn(rdev, "Failed to create debugfs directory\n");
1194         } else {
1195                 debugfs_create_u32("uA_load", 0444, regulator->debugfs,
1196                                    &regulator->uA_load);
1197                 debugfs_create_u32("min_uV", 0444, regulator->debugfs,
1198                                    &regulator->min_uV);
1199                 debugfs_create_u32("max_uV", 0444, regulator->debugfs,
1200                                    &regulator->max_uV);
1201         }
1202
1203         /*
1204          * Check now if the regulator is an always on regulator - if
1205          * it is then we don't need to do nearly so much work for
1206          * enable/disable calls.
1207          */
1208         if (!_regulator_can_change_status(rdev) &&
1209             _regulator_is_enabled(rdev))
1210                 regulator->always_on = true;
1211
1212         mutex_unlock(&rdev->mutex);
1213         return regulator;
1214 overflow_err:
1215         list_del(&regulator->list);
1216         kfree(regulator);
1217         mutex_unlock(&rdev->mutex);
1218         return NULL;
1219 }
1220
1221 static int _regulator_get_enable_time(struct regulator_dev *rdev)
1222 {
1223         if (rdev->constraints && rdev->constraints->enable_time)
1224                 return rdev->constraints->enable_time;
1225         if (!rdev->desc->ops->enable_time)
1226                 return rdev->desc->enable_time;
1227         return rdev->desc->ops->enable_time(rdev);
1228 }
1229
1230 static struct regulator_supply_alias *regulator_find_supply_alias(
1231                 struct device *dev, const char *supply)
1232 {
1233         struct regulator_supply_alias *map;
1234
1235         list_for_each_entry(map, &regulator_supply_alias_list, list)
1236                 if (map->src_dev == dev && strcmp(map->src_supply, supply) == 0)
1237                         return map;
1238
1239         return NULL;
1240 }
1241
1242 static void regulator_supply_alias(struct device **dev, const char **supply)
1243 {
1244         struct regulator_supply_alias *map;
1245
1246         map = regulator_find_supply_alias(*dev, *supply);
1247         if (map) {
1248                 dev_dbg(*dev, "Mapping supply %s to %s,%s\n",
1249                                 *supply, map->alias_supply,
1250                                 dev_name(map->alias_dev));
1251                 *dev = map->alias_dev;
1252                 *supply = map->alias_supply;
1253         }
1254 }
1255
1256 static struct regulator_dev *regulator_dev_lookup(struct device *dev,
1257                                                   const char *supply,
1258                                                   int *ret)
1259 {
1260         struct regulator_dev *r;
1261         struct device_node *node;
1262         struct regulator_map *map;
1263         const char *devname = NULL;
1264
1265         regulator_supply_alias(&dev, &supply);
1266
1267         /* first do a dt based lookup */
1268         if (dev && dev->of_node) {
1269                 node = of_get_regulator(dev, supply);
1270                 if (node) {
1271                         list_for_each_entry(r, &regulator_list, list)
1272                                 if (r->dev.parent &&
1273                                         node == r->dev.of_node)
1274                                         return r;
1275                         *ret = -EPROBE_DEFER;
1276                         return NULL;
1277                 } else {
1278                         /*
1279                          * If we couldn't even get the node then it's
1280                          * not just that the device didn't register
1281                          * yet, there's no node and we'll never
1282                          * succeed.
1283                          */
1284                         *ret = -ENODEV;
1285                 }
1286         }
1287
1288         /* if not found, try doing it non-dt way */
1289         if (dev)
1290                 devname = dev_name(dev);
1291
1292         list_for_each_entry(r, &regulator_list, list)
1293                 if (strcmp(rdev_get_name(r), supply) == 0)
1294                         return r;
1295
1296         list_for_each_entry(map, &regulator_map_list, list) {
1297                 /* If the mapping has a device set up it must match */
1298                 if (map->dev_name &&
1299                     (!devname || strcmp(map->dev_name, devname)))
1300                         continue;
1301
1302                 if (strcmp(map->supply, supply) == 0)
1303                         return map->regulator;
1304         }
1305
1306
1307         return NULL;
1308 }
1309
1310 /* Internal regulator request function */
1311 static struct regulator *_regulator_get(struct device *dev, const char *id,
1312                                         bool exclusive, bool allow_dummy)
1313 {
1314         struct regulator_dev *rdev;
1315         struct regulator *regulator = ERR_PTR(-EPROBE_DEFER);
1316         const char *devname = NULL;
1317         int ret;
1318
1319         if (id == NULL) {
1320                 pr_err("get() with no identifier\n");
1321                 return ERR_PTR(-EINVAL);
1322         }
1323
1324         if (dev)
1325                 devname = dev_name(dev);
1326
1327         if (have_full_constraints())
1328                 ret = -ENODEV;
1329         else
1330                 ret = -EPROBE_DEFER;
1331
1332         mutex_lock(&regulator_list_mutex);
1333
1334         rdev = regulator_dev_lookup(dev, id, &ret);
1335         if (rdev)
1336                 goto found;
1337
1338         regulator = ERR_PTR(ret);
1339
1340         /*
1341          * If we have return value from dev_lookup fail, we do not expect to
1342          * succeed, so, quit with appropriate error value
1343          */
1344         if (ret && ret != -ENODEV)
1345                 goto out;
1346
1347         if (!devname)
1348                 devname = "deviceless";
1349
1350         /*
1351          * Assume that a regulator is physically present and enabled
1352          * even if it isn't hooked up and just provide a dummy.
1353          */
1354         if (have_full_constraints() && allow_dummy) {
1355                 pr_warn("%s supply %s not found, using dummy regulator\n",
1356                         devname, id);
1357
1358                 rdev = dummy_regulator_rdev;
1359                 goto found;
1360         /* Don't log an error when called from regulator_get_optional() */
1361         } else if (!have_full_constraints() || exclusive) {
1362                 dev_err(dev, "dummy supplies not allowed\n");
1363         }
1364
1365         mutex_unlock(&regulator_list_mutex);
1366         return regulator;
1367
1368 found:
1369         if (rdev->exclusive) {
1370                 regulator = ERR_PTR(-EPERM);
1371                 goto out;
1372         }
1373
1374         if (exclusive && rdev->open_count) {
1375                 regulator = ERR_PTR(-EBUSY);
1376                 goto out;
1377         }
1378
1379         if (!try_module_get(rdev->owner))
1380                 goto out;
1381
1382         regulator = create_regulator(rdev, dev, id);
1383         if (regulator == NULL) {
1384                 regulator = ERR_PTR(-ENOMEM);
1385                 module_put(rdev->owner);
1386                 goto out;
1387         }
1388
1389         rdev->open_count++;
1390         if (exclusive) {
1391                 rdev->exclusive = 1;
1392
1393                 ret = _regulator_is_enabled(rdev);
1394                 if (ret > 0)
1395                         rdev->use_count = 1;
1396                 else
1397                         rdev->use_count = 0;
1398         }
1399
1400 out:
1401         mutex_unlock(&regulator_list_mutex);
1402
1403         return regulator;
1404 }
1405
1406 /**
1407  * regulator_get - lookup and obtain a reference to a regulator.
1408  * @dev: device for regulator "consumer"
1409  * @id: Supply name or regulator ID.
1410  *
1411  * Returns a struct regulator corresponding to the regulator producer,
1412  * or IS_ERR() condition containing errno.
1413  *
1414  * Use of supply names configured via regulator_set_device_supply() is
1415  * strongly encouraged.  It is recommended that the supply name used
1416  * should match the name used for the supply and/or the relevant
1417  * device pins in the datasheet.
1418  */
1419 struct regulator *regulator_get(struct device *dev, const char *id)
1420 {
1421         return _regulator_get(dev, id, false, true);
1422 }
1423 EXPORT_SYMBOL_GPL(regulator_get);
1424
1425 /**
1426  * regulator_get_exclusive - obtain exclusive access to a regulator.
1427  * @dev: device for regulator "consumer"
1428  * @id: Supply name or regulator ID.
1429  *
1430  * Returns a struct regulator corresponding to the regulator producer,
1431  * or IS_ERR() condition containing errno.  Other consumers will be
1432  * unable to obtain this reference is held and the use count for the
1433  * regulator will be initialised to reflect the current state of the
1434  * regulator.
1435  *
1436  * This is intended for use by consumers which cannot tolerate shared
1437  * use of the regulator such as those which need to force the
1438  * regulator off for correct operation of the hardware they are
1439  * controlling.
1440  *
1441  * Use of supply names configured via regulator_set_device_supply() is
1442  * strongly encouraged.  It is recommended that the supply name used
1443  * should match the name used for the supply and/or the relevant
1444  * device pins in the datasheet.
1445  */
1446 struct regulator *regulator_get_exclusive(struct device *dev, const char *id)
1447 {
1448         return _regulator_get(dev, id, true, false);
1449 }
1450 EXPORT_SYMBOL_GPL(regulator_get_exclusive);
1451
1452 /**
1453  * regulator_get_optional - obtain optional access to a regulator.
1454  * @dev: device for regulator "consumer"
1455  * @id: Supply name or regulator ID.
1456  *
1457  * Returns a struct regulator corresponding to the regulator producer,
1458  * or IS_ERR() condition containing errno.  Other consumers will be
1459  * unable to obtain this reference is held and the use count for the
1460  * regulator will be initialised to reflect the current state of the
1461  * regulator.
1462  *
1463  * This is intended for use by consumers for devices which can have
1464  * some supplies unconnected in normal use, such as some MMC devices.
1465  * It can allow the regulator core to provide stub supplies for other
1466  * supplies requested using normal regulator_get() calls without
1467  * disrupting the operation of drivers that can handle absent
1468  * supplies.
1469  *
1470  * Use of supply names configured via regulator_set_device_supply() is
1471  * strongly encouraged.  It is recommended that the supply name used
1472  * should match the name used for the supply and/or the relevant
1473  * device pins in the datasheet.
1474  */
1475 struct regulator *regulator_get_optional(struct device *dev, const char *id)
1476 {
1477         return _regulator_get(dev, id, false, false);
1478 }
1479 EXPORT_SYMBOL_GPL(regulator_get_optional);
1480
1481 /* Locks held by regulator_put() */
1482 static void _regulator_put(struct regulator *regulator)
1483 {
1484         struct regulator_dev *rdev;
1485
1486         if (regulator == NULL || IS_ERR(regulator))
1487                 return;
1488
1489         rdev = regulator->rdev;
1490
1491         debugfs_remove_recursive(regulator->debugfs);
1492
1493         /* remove any sysfs entries */
1494         if (regulator->dev)
1495                 sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
1496         kfree(regulator->supply_name);
1497         list_del(&regulator->list);
1498         kfree(regulator);
1499
1500         rdev->open_count--;
1501         rdev->exclusive = 0;
1502
1503         module_put(rdev->owner);
1504 }
1505
1506 /**
1507  * regulator_put - "free" the regulator source
1508  * @regulator: regulator source
1509  *
1510  * Note: drivers must ensure that all regulator_enable calls made on this
1511  * regulator source are balanced by regulator_disable calls prior to calling
1512  * this function.
1513  */
1514 void regulator_put(struct regulator *regulator)
1515 {
1516         mutex_lock(&regulator_list_mutex);
1517         _regulator_put(regulator);
1518         mutex_unlock(&regulator_list_mutex);
1519 }
1520 EXPORT_SYMBOL_GPL(regulator_put);
1521
1522 /**
1523  * regulator_register_supply_alias - Provide device alias for supply lookup
1524  *
1525  * @dev: device that will be given as the regulator "consumer"
1526  * @id: Supply name or regulator ID
1527  * @alias_dev: device that should be used to lookup the supply
1528  * @alias_id: Supply name or regulator ID that should be used to lookup the
1529  * supply
1530  *
1531  * All lookups for id on dev will instead be conducted for alias_id on
1532  * alias_dev.
1533  */
1534 int regulator_register_supply_alias(struct device *dev, const char *id,
1535                                     struct device *alias_dev,
1536                                     const char *alias_id)
1537 {
1538         struct regulator_supply_alias *map;
1539
1540         map = regulator_find_supply_alias(dev, id);
1541         if (map)
1542                 return -EEXIST;
1543
1544         map = kzalloc(sizeof(struct regulator_supply_alias), GFP_KERNEL);
1545         if (!map)
1546                 return -ENOMEM;
1547
1548         map->src_dev = dev;
1549         map->src_supply = id;
1550         map->alias_dev = alias_dev;
1551         map->alias_supply = alias_id;
1552
1553         list_add(&map->list, &regulator_supply_alias_list);
1554
1555         pr_info("Adding alias for supply %s,%s -> %s,%s\n",
1556                 id, dev_name(dev), alias_id, dev_name(alias_dev));
1557
1558         return 0;
1559 }
1560 EXPORT_SYMBOL_GPL(regulator_register_supply_alias);
1561
1562 /**
1563  * regulator_unregister_supply_alias - Remove device alias
1564  *
1565  * @dev: device that will be given as the regulator "consumer"
1566  * @id: Supply name or regulator ID
1567  *
1568  * Remove a lookup alias if one exists for id on dev.
1569  */
1570 void regulator_unregister_supply_alias(struct device *dev, const char *id)
1571 {
1572         struct regulator_supply_alias *map;
1573
1574         map = regulator_find_supply_alias(dev, id);
1575         if (map) {
1576                 list_del(&map->list);
1577                 kfree(map);
1578         }
1579 }
1580 EXPORT_SYMBOL_GPL(regulator_unregister_supply_alias);
1581
1582 /**
1583  * regulator_bulk_register_supply_alias - register multiple aliases
1584  *
1585  * @dev: device that will be given as the regulator "consumer"
1586  * @id: List of supply names or regulator IDs
1587  * @alias_dev: device that should be used to lookup the supply
1588  * @alias_id: List of supply names or regulator IDs that should be used to
1589  * lookup the supply
1590  * @num_id: Number of aliases to register
1591  *
1592  * @return 0 on success, an errno on failure.
1593  *
1594  * This helper function allows drivers to register several supply
1595  * aliases in one operation.  If any of the aliases cannot be
1596  * registered any aliases that were registered will be removed
1597  * before returning to the caller.
1598  */
1599 int regulator_bulk_register_supply_alias(struct device *dev, const char **id,
1600                                          struct device *alias_dev,
1601                                          const char **alias_id,
1602                                          int num_id)
1603 {
1604         int i;
1605         int ret;
1606
1607         for (i = 0; i < num_id; ++i) {
1608                 ret = regulator_register_supply_alias(dev, id[i], alias_dev,
1609                                                       alias_id[i]);
1610                 if (ret < 0)
1611                         goto err;
1612         }
1613
1614         return 0;
1615
1616 err:
1617         dev_err(dev,
1618                 "Failed to create supply alias %s,%s -> %s,%s\n",
1619                 id[i], dev_name(dev), alias_id[i], dev_name(alias_dev));
1620
1621         while (--i >= 0)
1622                 regulator_unregister_supply_alias(dev, id[i]);
1623
1624         return ret;
1625 }
1626 EXPORT_SYMBOL_GPL(regulator_bulk_register_supply_alias);
1627
1628 /**
1629  * regulator_bulk_unregister_supply_alias - unregister multiple aliases
1630  *
1631  * @dev: device that will be given as the regulator "consumer"
1632  * @id: List of supply names or regulator IDs
1633  * @num_id: Number of aliases to unregister
1634  *
1635  * This helper function allows drivers to unregister several supply
1636  * aliases in one operation.
1637  */
1638 void regulator_bulk_unregister_supply_alias(struct device *dev,
1639                                             const char **id,
1640                                             int num_id)
1641 {
1642         int i;
1643
1644         for (i = 0; i < num_id; ++i)
1645                 regulator_unregister_supply_alias(dev, id[i]);
1646 }
1647 EXPORT_SYMBOL_GPL(regulator_bulk_unregister_supply_alias);
1648
1649
1650 /* Manage enable GPIO list. Same GPIO pin can be shared among regulators */
1651 static int regulator_ena_gpio_request(struct regulator_dev *rdev,
1652                                 const struct regulator_config *config)
1653 {
1654         struct regulator_enable_gpio *pin;
1655         int ret;
1656
1657         list_for_each_entry(pin, &regulator_ena_gpio_list, list) {
1658                 if (pin->gpio == config->ena_gpio) {
1659                         rdev_dbg(rdev, "GPIO %d is already used\n",
1660                                 config->ena_gpio);
1661                         goto update_ena_gpio_to_rdev;
1662                 }
1663         }
1664
1665         ret = gpio_request_one(config->ena_gpio,
1666                                 GPIOF_DIR_OUT | config->ena_gpio_flags,
1667                                 rdev_get_name(rdev));
1668         if (ret)
1669                 return ret;
1670
1671         pin = kzalloc(sizeof(struct regulator_enable_gpio), GFP_KERNEL);
1672         if (pin == NULL) {
1673                 gpio_free(config->ena_gpio);
1674                 return -ENOMEM;
1675         }
1676
1677         pin->gpio = config->ena_gpio;
1678         pin->ena_gpio_invert = config->ena_gpio_invert;
1679         list_add(&pin->list, &regulator_ena_gpio_list);
1680
1681 update_ena_gpio_to_rdev:
1682         pin->request_count++;
1683         rdev->ena_pin = pin;
1684         return 0;
1685 }
1686
1687 static void regulator_ena_gpio_free(struct regulator_dev *rdev)
1688 {
1689         struct regulator_enable_gpio *pin, *n;
1690
1691         if (!rdev->ena_pin)
1692                 return;
1693
1694         /* Free the GPIO only in case of no use */
1695         list_for_each_entry_safe(pin, n, &regulator_ena_gpio_list, list) {
1696                 if (pin->gpio == rdev->ena_pin->gpio) {
1697                         if (pin->request_count <= 1) {
1698                                 pin->request_count = 0;
1699                                 gpio_free(pin->gpio);
1700                                 list_del(&pin->list);
1701                                 kfree(pin);
1702                         } else {
1703                                 pin->request_count--;
1704                         }
1705                 }
1706         }
1707 }
1708
1709 /**
1710  * regulator_ena_gpio_ctrl - balance enable_count of each GPIO and actual GPIO pin control
1711  * @rdev: regulator_dev structure
1712  * @enable: enable GPIO at initial use?
1713  *
1714  * GPIO is enabled in case of initial use. (enable_count is 0)
1715  * GPIO is disabled when it is not shared any more. (enable_count <= 1)
1716  */
1717 static int regulator_ena_gpio_ctrl(struct regulator_dev *rdev, bool enable)
1718 {
1719         struct regulator_enable_gpio *pin = rdev->ena_pin;
1720
1721         if (!pin)
1722                 return -EINVAL;
1723
1724         if (enable) {
1725                 /* Enable GPIO at initial use */
1726                 if (pin->enable_count == 0)
1727                         gpio_set_value_cansleep(pin->gpio,
1728                                                 !pin->ena_gpio_invert);
1729
1730                 pin->enable_count++;
1731         } else {
1732                 if (pin->enable_count > 1) {
1733                         pin->enable_count--;
1734                         return 0;
1735                 }
1736
1737                 /* Disable GPIO if not used */
1738                 if (pin->enable_count <= 1) {
1739                         gpio_set_value_cansleep(pin->gpio,
1740                                                 pin->ena_gpio_invert);
1741                         pin->enable_count = 0;
1742                 }
1743         }
1744
1745         return 0;
1746 }
1747
1748 static int _regulator_do_enable(struct regulator_dev *rdev)
1749 {
1750         int ret, delay;
1751
1752         /* Query before enabling in case configuration dependent.  */
1753         ret = _regulator_get_enable_time(rdev);
1754         if (ret >= 0) {
1755                 delay = ret;
1756         } else {
1757                 rdev_warn(rdev, "enable_time() failed: %d\n", ret);
1758                 delay = 0;
1759         }
1760
1761         trace_regulator_enable(rdev_get_name(rdev));
1762
1763         if (rdev->ena_pin) {
1764                 ret = regulator_ena_gpio_ctrl(rdev, true);
1765                 if (ret < 0)
1766                         return ret;
1767                 rdev->ena_gpio_state = 1;
1768         } else if (rdev->desc->ops->enable) {
1769                 ret = rdev->desc->ops->enable(rdev);
1770                 if (ret < 0)
1771                         return ret;
1772         } else {
1773                 return -EINVAL;
1774         }
1775
1776         /* Allow the regulator to ramp; it would be useful to extend
1777          * this for bulk operations so that the regulators can ramp
1778          * together.  */
1779         trace_regulator_enable_delay(rdev_get_name(rdev));
1780
1781         /*
1782          * Delay for the requested amount of time as per the guidelines in:
1783          *
1784          *     Documentation/timers/timers-howto.txt
1785          *
1786          * The assumption here is that regulators will never be enabled in
1787          * atomic context and therefore sleeping functions can be used.
1788          */
1789         if (delay) {
1790                 unsigned int ms = delay / 1000;
1791                 unsigned int us = delay % 1000;
1792
1793                 if (ms > 0) {
1794                         /*
1795                          * For small enough values, handle super-millisecond
1796                          * delays in the usleep_range() call below.
1797                          */
1798                         if (ms < 20)
1799                                 us += ms * 1000;
1800                         else
1801                                 msleep(ms);
1802                 }
1803
1804                 /*
1805                  * Give the scheduler some room to coalesce with any other
1806                  * wakeup sources. For delays shorter than 10 us, don't even
1807                  * bother setting up high-resolution timers and just busy-
1808                  * loop.
1809                  */
1810                 if (us >= 10)
1811                         usleep_range(us, us + 100);
1812                 else
1813                         udelay(us);
1814         }
1815
1816         trace_regulator_enable_complete(rdev_get_name(rdev));
1817
1818         return 0;
1819 }
1820
1821 /* locks held by regulator_enable() */
1822 static int _regulator_enable(struct regulator_dev *rdev)
1823 {
1824         int ret;
1825
1826         /* check voltage and requested load before enabling */
1827         if (rdev->constraints &&
1828             (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS))
1829                 drms_uA_update(rdev);
1830
1831         if (rdev->use_count == 0) {
1832                 /* The regulator may on if it's not switchable or left on */
1833                 ret = _regulator_is_enabled(rdev);
1834                 if (ret == -EINVAL || ret == 0) {
1835                         if (!_regulator_can_change_status(rdev))
1836                                 return -EPERM;
1837
1838                         ret = _regulator_do_enable(rdev);
1839                         if (ret < 0)
1840                                 return ret;
1841
1842                 } else if (ret < 0) {
1843                         rdev_err(rdev, "is_enabled() failed: %d\n", ret);
1844                         return ret;
1845                 }
1846                 /* Fallthrough on positive return values - already enabled */
1847         }
1848
1849         rdev->use_count++;
1850
1851         return 0;
1852 }
1853
1854 /**
1855  * regulator_enable - enable regulator output
1856  * @regulator: regulator source
1857  *
1858  * Request that the regulator be enabled with the regulator output at
1859  * the predefined voltage or current value.  Calls to regulator_enable()
1860  * must be balanced with calls to regulator_disable().
1861  *
1862  * NOTE: the output value can be set by other drivers, boot loader or may be
1863  * hardwired in the regulator.
1864  */
1865 int regulator_enable(struct regulator *regulator)
1866 {
1867         struct regulator_dev *rdev = regulator->rdev;
1868         int ret = 0;
1869
1870         if (regulator->always_on)
1871                 return 0;
1872
1873         if (rdev->supply) {
1874                 ret = regulator_enable(rdev->supply);
1875                 if (ret != 0)
1876                         return ret;
1877         }
1878
1879         mutex_lock(&rdev->mutex);
1880         ret = _regulator_enable(rdev);
1881         mutex_unlock(&rdev->mutex);
1882
1883         if (ret != 0 && rdev->supply)
1884                 regulator_disable(rdev->supply);
1885
1886         return ret;
1887 }
1888 EXPORT_SYMBOL_GPL(regulator_enable);
1889
1890 static int _regulator_do_disable(struct regulator_dev *rdev)
1891 {
1892         int ret;
1893
1894         trace_regulator_disable(rdev_get_name(rdev));
1895
1896         if (rdev->ena_pin) {
1897                 ret = regulator_ena_gpio_ctrl(rdev, false);
1898                 if (ret < 0)
1899                         return ret;
1900                 rdev->ena_gpio_state = 0;
1901
1902         } else if (rdev->desc->ops->disable) {
1903                 ret = rdev->desc->ops->disable(rdev);
1904                 if (ret != 0)
1905                         return ret;
1906         }
1907
1908         trace_regulator_disable_complete(rdev_get_name(rdev));
1909
1910         _notifier_call_chain(rdev, REGULATOR_EVENT_DISABLE,
1911                              NULL);
1912         return 0;
1913 }
1914
1915 /* locks held by regulator_disable() */
1916 static int _regulator_disable(struct regulator_dev *rdev)
1917 {
1918         int ret = 0;
1919
1920         if (WARN(rdev->use_count <= 0,
1921                  "unbalanced disables for %s\n", rdev_get_name(rdev)))
1922                 return -EIO;
1923
1924         /* are we the last user and permitted to disable ? */
1925         if (rdev->use_count == 1 &&
1926             (rdev->constraints && !rdev->constraints->always_on)) {
1927
1928                 /* we are last user */
1929                 if (_regulator_can_change_status(rdev)) {
1930                         ret = _regulator_do_disable(rdev);
1931                         if (ret < 0) {
1932                                 rdev_err(rdev, "failed to disable\n");
1933                                 return ret;
1934                         }
1935                 }
1936
1937                 rdev->use_count = 0;
1938         } else if (rdev->use_count > 1) {
1939
1940                 if (rdev->constraints &&
1941                         (rdev->constraints->valid_ops_mask &
1942                         REGULATOR_CHANGE_DRMS))
1943                         drms_uA_update(rdev);
1944
1945                 rdev->use_count--;
1946         }
1947
1948         return ret;
1949 }
1950
1951 /**
1952  * regulator_disable - disable regulator output
1953  * @regulator: regulator source
1954  *
1955  * Disable the regulator output voltage or current.  Calls to
1956  * regulator_enable() must be balanced with calls to
1957  * regulator_disable().
1958  *
1959  * NOTE: this will only disable the regulator output if no other consumer
1960  * devices have it enabled, the regulator device supports disabling and
1961  * machine constraints permit this operation.
1962  */
1963 int regulator_disable(struct regulator *regulator)
1964 {
1965         struct regulator_dev *rdev = regulator->rdev;
1966         int ret = 0;
1967
1968         if (regulator->always_on)
1969                 return 0;
1970
1971         mutex_lock(&rdev->mutex);
1972         ret = _regulator_disable(rdev);
1973         mutex_unlock(&rdev->mutex);
1974
1975         if (ret == 0 && rdev->supply)
1976                 regulator_disable(rdev->supply);
1977
1978         return ret;
1979 }
1980 EXPORT_SYMBOL_GPL(regulator_disable);
1981
1982 /* locks held by regulator_force_disable() */
1983 static int _regulator_force_disable(struct regulator_dev *rdev)
1984 {
1985         int ret = 0;
1986
1987         /* force disable */
1988         if (rdev->desc->ops->disable) {
1989                 /* ah well, who wants to live forever... */
1990                 ret = rdev->desc->ops->disable(rdev);
1991                 if (ret < 0) {
1992                         rdev_err(rdev, "failed to force disable\n");
1993                         return ret;
1994                 }
1995                 /* notify other consumers that power has been forced off */
1996                 _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
1997                         REGULATOR_EVENT_DISABLE, NULL);
1998         }
1999
2000         return ret;
2001 }
2002
2003 /**
2004  * regulator_force_disable - force disable regulator output
2005  * @regulator: regulator source
2006  *
2007  * Forcibly disable the regulator output voltage or current.
2008  * NOTE: this *will* disable the regulator output even if other consumer
2009  * devices have it enabled. This should be used for situations when device
2010  * damage will likely occur if the regulator is not disabled (e.g. over temp).
2011  */
2012 int regulator_force_disable(struct regulator *regulator)
2013 {
2014         struct regulator_dev *rdev = regulator->rdev;
2015         int ret;
2016
2017         mutex_lock(&rdev->mutex);
2018         regulator->uA_load = 0;
2019         ret = _regulator_force_disable(regulator->rdev);
2020         mutex_unlock(&rdev->mutex);
2021
2022         if (rdev->supply)
2023                 while (rdev->open_count--)
2024                         regulator_disable(rdev->supply);
2025
2026         return ret;
2027 }
2028 EXPORT_SYMBOL_GPL(regulator_force_disable);
2029
2030 static void regulator_disable_work(struct work_struct *work)
2031 {
2032         struct regulator_dev *rdev = container_of(work, struct regulator_dev,
2033                                                   disable_work.work);
2034         int count, i, ret;
2035
2036         mutex_lock(&rdev->mutex);
2037
2038         BUG_ON(!rdev->deferred_disables);
2039
2040         count = rdev->deferred_disables;
2041         rdev->deferred_disables = 0;
2042
2043         for (i = 0; i < count; i++) {
2044                 ret = _regulator_disable(rdev);
2045                 if (ret != 0)
2046                         rdev_err(rdev, "Deferred disable failed: %d\n", ret);
2047         }
2048
2049         mutex_unlock(&rdev->mutex);
2050
2051         if (rdev->supply) {
2052                 for (i = 0; i < count; i++) {
2053                         ret = regulator_disable(rdev->supply);
2054                         if (ret != 0) {
2055                                 rdev_err(rdev,
2056                                          "Supply disable failed: %d\n", ret);
2057                         }
2058                 }
2059         }
2060 }
2061
2062 /**
2063  * regulator_disable_deferred - disable regulator output with delay
2064  * @regulator: regulator source
2065  * @ms: miliseconds until the regulator is disabled
2066  *
2067  * Execute regulator_disable() on the regulator after a delay.  This
2068  * is intended for use with devices that require some time to quiesce.
2069  *
2070  * NOTE: this will only disable the regulator output if no other consumer
2071  * devices have it enabled, the regulator device supports disabling and
2072  * machine constraints permit this operation.
2073  */
2074 int regulator_disable_deferred(struct regulator *regulator, int ms)
2075 {
2076         struct regulator_dev *rdev = regulator->rdev;
2077         int ret;
2078
2079         if (regulator->always_on)
2080                 return 0;
2081
2082         if (!ms)
2083                 return regulator_disable(regulator);
2084
2085         mutex_lock(&rdev->mutex);
2086         rdev->deferred_disables++;
2087         mutex_unlock(&rdev->mutex);
2088
2089         ret = queue_delayed_work(system_power_efficient_wq,
2090                                  &rdev->disable_work,
2091                                  msecs_to_jiffies(ms));
2092         if (ret < 0)
2093                 return ret;
2094         else
2095                 return 0;
2096 }
2097 EXPORT_SYMBOL_GPL(regulator_disable_deferred);
2098
2099 static int _regulator_is_enabled(struct regulator_dev *rdev)
2100 {
2101         /* A GPIO control always takes precedence */
2102         if (rdev->ena_pin)
2103                 return rdev->ena_gpio_state;
2104
2105         /* If we don't know then assume that the regulator is always on */
2106         if (!rdev->desc->ops->is_enabled)
2107                 return 1;
2108
2109         return rdev->desc->ops->is_enabled(rdev);
2110 }
2111
2112 /**
2113  * regulator_is_enabled - is the regulator output enabled
2114  * @regulator: regulator source
2115  *
2116  * Returns positive if the regulator driver backing the source/client
2117  * has requested that the device be enabled, zero if it hasn't, else a
2118  * negative errno code.
2119  *
2120  * Note that the device backing this regulator handle can have multiple
2121  * users, so it might be enabled even if regulator_enable() was never
2122  * called for this particular source.
2123  */
2124 int regulator_is_enabled(struct regulator *regulator)
2125 {
2126         int ret;
2127
2128         if (regulator->always_on)
2129                 return 1;
2130
2131         mutex_lock(&regulator->rdev->mutex);
2132         ret = _regulator_is_enabled(regulator->rdev);
2133         mutex_unlock(&regulator->rdev->mutex);
2134
2135         return ret;
2136 }
2137 EXPORT_SYMBOL_GPL(regulator_is_enabled);
2138
2139 /**
2140  * regulator_can_change_voltage - check if regulator can change voltage
2141  * @regulator: regulator source
2142  *
2143  * Returns positive if the regulator driver backing the source/client
2144  * can change its voltage, false otherwise. Usefull for detecting fixed
2145  * or dummy regulators and disabling voltage change logic in the client
2146  * driver.
2147  */
2148 int regulator_can_change_voltage(struct regulator *regulator)
2149 {
2150         struct regulator_dev    *rdev = regulator->rdev;
2151
2152         if (rdev->constraints &&
2153             (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
2154                 if (rdev->desc->n_voltages - rdev->desc->linear_min_sel > 1)
2155                         return 1;
2156
2157                 if (rdev->desc->continuous_voltage_range &&
2158                     rdev->constraints->min_uV && rdev->constraints->max_uV &&
2159                     rdev->constraints->min_uV != rdev->constraints->max_uV)
2160                         return 1;
2161         }
2162
2163         return 0;
2164 }
2165 EXPORT_SYMBOL_GPL(regulator_can_change_voltage);
2166
2167 /**
2168  * regulator_count_voltages - count regulator_list_voltage() selectors
2169  * @regulator: regulator source
2170  *
2171  * Returns number of selectors, or negative errno.  Selectors are
2172  * numbered starting at zero, and typically correspond to bitfields
2173  * in hardware registers.
2174  */
2175 int regulator_count_voltages(struct regulator *regulator)
2176 {
2177         struct regulator_dev    *rdev = regulator->rdev;
2178
2179         return rdev->desc->n_voltages ? : -EINVAL;
2180 }
2181 EXPORT_SYMBOL_GPL(regulator_count_voltages);
2182
2183 /**
2184  * regulator_list_voltage - enumerate supported voltages
2185  * @regulator: regulator source
2186  * @selector: identify voltage to list
2187  * Context: can sleep
2188  *
2189  * Returns a voltage that can be passed to @regulator_set_voltage(),
2190  * zero if this selector code can't be used on this system, or a
2191  * negative errno.
2192  */
2193 int regulator_list_voltage(struct regulator *regulator, unsigned selector)
2194 {
2195         struct regulator_dev    *rdev = regulator->rdev;
2196         struct regulator_ops    *ops = rdev->desc->ops;
2197         int                     ret;
2198
2199         if (rdev->desc->fixed_uV && rdev->desc->n_voltages == 1 && !selector)
2200                 return rdev->desc->fixed_uV;
2201
2202         if (!ops->list_voltage || selector >= rdev->desc->n_voltages)
2203                 return -EINVAL;
2204
2205         mutex_lock(&rdev->mutex);
2206         ret = ops->list_voltage(rdev, selector);
2207         mutex_unlock(&rdev->mutex);
2208
2209         if (ret > 0) {
2210                 if (ret < rdev->constraints->min_uV)
2211                         ret = 0;
2212                 else if (ret > rdev->constraints->max_uV)
2213                         ret = 0;
2214         }
2215
2216         return ret;
2217 }
2218 EXPORT_SYMBOL_GPL(regulator_list_voltage);
2219
2220 /**
2221  * regulator_get_linear_step - return the voltage step size between VSEL values
2222  * @regulator: regulator source
2223  *
2224  * Returns the voltage step size between VSEL values for linear
2225  * regulators, or return 0 if the regulator isn't a linear regulator.
2226  */
2227 unsigned int regulator_get_linear_step(struct regulator *regulator)
2228 {
2229         struct regulator_dev *rdev = regulator->rdev;
2230
2231         return rdev->desc->uV_step;
2232 }
2233 EXPORT_SYMBOL_GPL(regulator_get_linear_step);
2234
2235 /**
2236  * regulator_is_supported_voltage - check if a voltage range can be supported
2237  *
2238  * @regulator: Regulator to check.
2239  * @min_uV: Minimum required voltage in uV.
2240  * @max_uV: Maximum required voltage in uV.
2241  *
2242  * Returns a boolean or a negative error code.
2243  */
2244 int regulator_is_supported_voltage(struct regulator *regulator,
2245                                    int min_uV, int max_uV)
2246 {
2247         struct regulator_dev *rdev = regulator->rdev;
2248         int i, voltages, ret;
2249
2250         /* If we can't change voltage check the current voltage */
2251         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
2252                 ret = regulator_get_voltage(regulator);
2253                 if (ret >= 0)
2254                         return min_uV <= ret && ret <= max_uV;
2255                 else
2256                         return ret;
2257         }
2258
2259         /* Any voltage within constrains range is fine? */
2260         if (rdev->desc->continuous_voltage_range)
2261                 return min_uV >= rdev->constraints->min_uV &&
2262                                 max_uV <= rdev->constraints->max_uV;
2263
2264         ret = regulator_count_voltages(regulator);
2265         if (ret < 0)
2266                 return ret;
2267         voltages = ret;
2268
2269         for (i = 0; i < voltages; i++) {
2270                 ret = regulator_list_voltage(regulator, i);
2271
2272                 if (ret >= min_uV && ret <= max_uV)
2273                         return 1;
2274         }
2275
2276         return 0;
2277 }
2278 EXPORT_SYMBOL_GPL(regulator_is_supported_voltage);
2279
2280 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
2281                                      int min_uV, int max_uV)
2282 {
2283         int ret;
2284         int delay = 0;
2285         int best_val = 0;
2286         unsigned int selector;
2287         int old_selector = -1;
2288
2289         trace_regulator_set_voltage(rdev_get_name(rdev), min_uV, max_uV);
2290
2291         min_uV += rdev->constraints->uV_offset;
2292         max_uV += rdev->constraints->uV_offset;
2293
2294         /*
2295          * If we can't obtain the old selector there is not enough
2296          * info to call set_voltage_time_sel().
2297          */
2298         if (_regulator_is_enabled(rdev) &&
2299             rdev->desc->ops->set_voltage_time_sel &&
2300             rdev->desc->ops->get_voltage_sel) {
2301                 old_selector = rdev->desc->ops->get_voltage_sel(rdev);
2302                 if (old_selector < 0)
2303                         return old_selector;
2304         }
2305
2306         if (rdev->desc->ops->set_voltage) {
2307                 ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV,
2308                                                    &selector);
2309
2310                 if (ret >= 0) {
2311                         if (rdev->desc->ops->list_voltage)
2312                                 best_val = rdev->desc->ops->list_voltage(rdev,
2313                                                                          selector);
2314                         else
2315                                 best_val = _regulator_get_voltage(rdev);
2316                 }
2317
2318         } else if (rdev->desc->ops->set_voltage_sel) {
2319                 if (rdev->desc->ops->map_voltage) {
2320                         ret = rdev->desc->ops->map_voltage(rdev, min_uV,
2321                                                            max_uV);
2322                 } else {
2323                         if (rdev->desc->ops->list_voltage ==
2324                             regulator_list_voltage_linear)
2325                                 ret = regulator_map_voltage_linear(rdev,
2326                                                                 min_uV, max_uV);
2327                         else
2328                                 ret = regulator_map_voltage_iterate(rdev,
2329                                                                 min_uV, max_uV);
2330                 }
2331
2332                 if (ret >= 0) {
2333                         best_val = rdev->desc->ops->list_voltage(rdev, ret);
2334                         if (min_uV <= best_val && max_uV >= best_val) {
2335                                 selector = ret;
2336                                 if (old_selector == selector)
2337                                         ret = 0;
2338                                 else
2339                                         ret = rdev->desc->ops->set_voltage_sel(
2340                                                                 rdev, ret);
2341                         } else {
2342                                 ret = -EINVAL;
2343                         }
2344                 }
2345         } else {
2346                 ret = -EINVAL;
2347         }
2348
2349         /* Call set_voltage_time_sel if successfully obtained old_selector */
2350         if (ret == 0 && !rdev->constraints->ramp_disable && old_selector >= 0
2351                 && old_selector != selector) {
2352
2353                 delay = rdev->desc->ops->set_voltage_time_sel(rdev,
2354                                                 old_selector, selector);
2355                 if (delay < 0) {
2356                         rdev_warn(rdev, "set_voltage_time_sel() failed: %d\n",
2357                                   delay);
2358                         delay = 0;
2359                 }
2360
2361                 /* Insert any necessary delays */
2362                 if (delay >= 1000) {
2363                         mdelay(delay / 1000);
2364                         udelay(delay % 1000);
2365                 } else if (delay) {
2366                         udelay(delay);
2367                 }
2368         }
2369
2370         if (ret == 0 && best_val >= 0) {
2371                 unsigned long data = best_val;
2372
2373                 _notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE,
2374                                      (void *)data);
2375         }
2376
2377         trace_regulator_set_voltage_complete(rdev_get_name(rdev), best_val);
2378
2379         return ret;
2380 }
2381
2382 /**
2383  * regulator_set_voltage - set regulator output voltage
2384  * @regulator: regulator source
2385  * @min_uV: Minimum required voltage in uV
2386  * @max_uV: Maximum acceptable voltage in uV
2387  *
2388  * Sets a voltage regulator to the desired output voltage. This can be set
2389  * during any regulator state. IOW, regulator can be disabled or enabled.
2390  *
2391  * If the regulator is enabled then the voltage will change to the new value
2392  * immediately otherwise if the regulator is disabled the regulator will
2393  * output at the new voltage when enabled.
2394  *
2395  * NOTE: If the regulator is shared between several devices then the lowest
2396  * request voltage that meets the system constraints will be used.
2397  * Regulator system constraints must be set for this regulator before
2398  * calling this function otherwise this call will fail.
2399  */
2400 int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
2401 {
2402         struct regulator_dev *rdev = regulator->rdev;
2403         int ret = 0;
2404         int old_min_uV, old_max_uV;
2405
2406         mutex_lock(&rdev->mutex);
2407
2408         /* If we're setting the same range as last time the change
2409          * should be a noop (some cpufreq implementations use the same
2410          * voltage for multiple frequencies, for example).
2411          */
2412         if (regulator->min_uV == min_uV && regulator->max_uV == max_uV)
2413                 goto out;
2414
2415         /* sanity check */
2416         if (!rdev->desc->ops->set_voltage &&
2417             !rdev->desc->ops->set_voltage_sel) {
2418                 ret = -EINVAL;
2419                 goto out;
2420         }
2421
2422         /* constraints check */
2423         ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
2424         if (ret < 0)
2425                 goto out;
2426
2427         /* restore original values in case of error */
2428         old_min_uV = regulator->min_uV;
2429         old_max_uV = regulator->max_uV;
2430         regulator->min_uV = min_uV;
2431         regulator->max_uV = max_uV;
2432
2433         ret = regulator_check_consumers(rdev, &min_uV, &max_uV);
2434         if (ret < 0)
2435                 goto out2;
2436
2437         ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
2438         if (ret < 0)
2439                 goto out2;
2440
2441 out:
2442         mutex_unlock(&rdev->mutex);
2443         return ret;
2444 out2:
2445         regulator->min_uV = old_min_uV;
2446         regulator->max_uV = old_max_uV;
2447         mutex_unlock(&rdev->mutex);
2448         return ret;
2449 }
2450 EXPORT_SYMBOL_GPL(regulator_set_voltage);
2451
2452 /**
2453  * regulator_set_voltage_time - get raise/fall time
2454  * @regulator: regulator source
2455  * @old_uV: starting voltage in microvolts
2456  * @new_uV: target voltage in microvolts
2457  *
2458  * Provided with the starting and ending voltage, this function attempts to
2459  * calculate the time in microseconds required to rise or fall to this new
2460  * voltage.
2461  */
2462 int regulator_set_voltage_time(struct regulator *regulator,
2463                                int old_uV, int new_uV)
2464 {
2465         struct regulator_dev    *rdev = regulator->rdev;
2466         struct regulator_ops    *ops = rdev->desc->ops;
2467         int old_sel = -1;
2468         int new_sel = -1;
2469         int voltage;
2470         int i;
2471
2472         /* Currently requires operations to do this */
2473         if (!ops->list_voltage || !ops->set_voltage_time_sel
2474             || !rdev->desc->n_voltages)
2475                 return -EINVAL;
2476
2477         for (i = 0; i < rdev->desc->n_voltages; i++) {
2478                 /* We only look for exact voltage matches here */
2479                 voltage = regulator_list_voltage(regulator, i);
2480                 if (voltage < 0)
2481                         return -EINVAL;
2482                 if (voltage == 0)
2483                         continue;
2484                 if (voltage == old_uV)
2485                         old_sel = i;
2486                 if (voltage == new_uV)
2487                         new_sel = i;
2488         }
2489
2490         if (old_sel < 0 || new_sel < 0)
2491                 return -EINVAL;
2492
2493         return ops->set_voltage_time_sel(rdev, old_sel, new_sel);
2494 }
2495 EXPORT_SYMBOL_GPL(regulator_set_voltage_time);
2496
2497 /**
2498  * regulator_set_voltage_time_sel - get raise/fall time
2499  * @rdev: regulator source device
2500  * @old_selector: selector for starting voltage
2501  * @new_selector: selector for target voltage
2502  *
2503  * Provided with the starting and target voltage selectors, this function
2504  * returns time in microseconds required to rise or fall to this new voltage
2505  *
2506  * Drivers providing ramp_delay in regulation_constraints can use this as their
2507  * set_voltage_time_sel() operation.
2508  */
2509 int regulator_set_voltage_time_sel(struct regulator_dev *rdev,
2510                                    unsigned int old_selector,
2511                                    unsigned int new_selector)
2512 {
2513         unsigned int ramp_delay = 0;
2514         int old_volt, new_volt;
2515
2516         if (rdev->constraints->ramp_delay)
2517                 ramp_delay = rdev->constraints->ramp_delay;
2518         else if (rdev->desc->ramp_delay)
2519                 ramp_delay = rdev->desc->ramp_delay;
2520
2521         if (ramp_delay == 0) {
2522                 rdev_warn(rdev, "ramp_delay not set\n");
2523                 return 0;
2524         }
2525
2526         /* sanity check */
2527         if (!rdev->desc->ops->list_voltage)
2528                 return -EINVAL;
2529
2530         old_volt = rdev->desc->ops->list_voltage(rdev, old_selector);
2531         new_volt = rdev->desc->ops->list_voltage(rdev, new_selector);
2532
2533         return DIV_ROUND_UP(abs(new_volt - old_volt), ramp_delay);
2534 }
2535 EXPORT_SYMBOL_GPL(regulator_set_voltage_time_sel);
2536
2537 /**
2538  * regulator_sync_voltage - re-apply last regulator output voltage
2539  * @regulator: regulator source
2540  *
2541  * Re-apply the last configured voltage.  This is intended to be used
2542  * where some external control source the consumer is cooperating with
2543  * has caused the configured voltage to change.
2544  */
2545 int regulator_sync_voltage(struct regulator *regulator)
2546 {
2547         struct regulator_dev *rdev = regulator->rdev;
2548         int ret, min_uV, max_uV;
2549
2550         mutex_lock(&rdev->mutex);
2551
2552         if (!rdev->desc->ops->set_voltage &&
2553             !rdev->desc->ops->set_voltage_sel) {
2554                 ret = -EINVAL;
2555                 goto out;
2556         }
2557
2558         /* This is only going to work if we've had a voltage configured. */
2559         if (!regulator->min_uV && !regulator->max_uV) {
2560                 ret = -EINVAL;
2561                 goto out;
2562         }
2563
2564         min_uV = regulator->min_uV;
2565         max_uV = regulator->max_uV;
2566
2567         /* This should be a paranoia check... */
2568         ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
2569         if (ret < 0)
2570                 goto out;
2571
2572         ret = regulator_check_consumers(rdev, &min_uV, &max_uV);
2573         if (ret < 0)
2574                 goto out;
2575
2576         ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
2577
2578 out:
2579         mutex_unlock(&rdev->mutex);
2580         return ret;
2581 }
2582 EXPORT_SYMBOL_GPL(regulator_sync_voltage);
2583
2584 static int _regulator_get_voltage(struct regulator_dev *rdev)
2585 {
2586         int sel, ret;
2587
2588         if (rdev->desc->ops->get_voltage_sel) {
2589                 sel = rdev->desc->ops->get_voltage_sel(rdev);
2590                 if (sel < 0)
2591                         return sel;
2592                 ret = rdev->desc->ops->list_voltage(rdev, sel);
2593         } else if (rdev->desc->ops->get_voltage) {
2594                 ret = rdev->desc->ops->get_voltage(rdev);
2595         } else if (rdev->desc->ops->list_voltage) {
2596                 ret = rdev->desc->ops->list_voltage(rdev, 0);
2597         } else if (rdev->desc->fixed_uV && (rdev->desc->n_voltages == 1)) {
2598                 ret = rdev->desc->fixed_uV;
2599         } else {
2600                 return -EINVAL;
2601         }
2602
2603         if (ret < 0)
2604                 return ret;
2605         return ret - rdev->constraints->uV_offset;
2606 }
2607
2608 /**
2609  * regulator_get_voltage - get regulator output voltage
2610  * @regulator: regulator source
2611  *
2612  * This returns the current regulator voltage in uV.
2613  *
2614  * NOTE: If the regulator is disabled it will return the voltage value. This
2615  * function should not be used to determine regulator state.
2616  */
2617 int regulator_get_voltage(struct regulator *regulator)
2618 {
2619         int ret;
2620
2621         mutex_lock(&regulator->rdev->mutex);
2622
2623         ret = _regulator_get_voltage(regulator->rdev);
2624
2625         mutex_unlock(&regulator->rdev->mutex);
2626
2627         return ret;
2628 }
2629 EXPORT_SYMBOL_GPL(regulator_get_voltage);
2630
2631 /**
2632  * regulator_set_current_limit - set regulator output current limit
2633  * @regulator: regulator source
2634  * @min_uA: Minimum supported current in uA
2635  * @max_uA: Maximum supported current in uA
2636  *
2637  * Sets current sink to the desired output current. This can be set during
2638  * any regulator state. IOW, regulator can be disabled or enabled.
2639  *
2640  * If the regulator is enabled then the current will change to the new value
2641  * immediately otherwise if the regulator is disabled the regulator will
2642  * output at the new current when enabled.
2643  *
2644  * NOTE: Regulator system constraints must be set for this regulator before
2645  * calling this function otherwise this call will fail.
2646  */
2647 int regulator_set_current_limit(struct regulator *regulator,
2648                                int min_uA, int max_uA)
2649 {
2650         struct regulator_dev *rdev = regulator->rdev;
2651         int ret;
2652
2653         mutex_lock(&rdev->mutex);
2654
2655         /* sanity check */
2656         if (!rdev->desc->ops->set_current_limit) {
2657                 ret = -EINVAL;
2658                 goto out;
2659         }
2660
2661         /* constraints check */
2662         ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
2663         if (ret < 0)
2664                 goto out;
2665
2666         ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
2667 out:
2668         mutex_unlock(&rdev->mutex);
2669         return ret;
2670 }
2671 EXPORT_SYMBOL_GPL(regulator_set_current_limit);
2672
2673 static int _regulator_get_current_limit(struct regulator_dev *rdev)
2674 {
2675         int ret;
2676
2677         mutex_lock(&rdev->mutex);
2678
2679         /* sanity check */
2680         if (!rdev->desc->ops->get_current_limit) {
2681                 ret = -EINVAL;
2682                 goto out;
2683         }
2684
2685         ret = rdev->desc->ops->get_current_limit(rdev);
2686 out:
2687         mutex_unlock(&rdev->mutex);
2688         return ret;
2689 }
2690
2691 /**
2692  * regulator_get_current_limit - get regulator output current
2693  * @regulator: regulator source
2694  *
2695  * This returns the current supplied by the specified current sink in uA.
2696  *
2697  * NOTE: If the regulator is disabled it will return the current value. This
2698  * function should not be used to determine regulator state.
2699  */
2700 int regulator_get_current_limit(struct regulator *regulator)
2701 {
2702         return _regulator_get_current_limit(regulator->rdev);
2703 }
2704 EXPORT_SYMBOL_GPL(regulator_get_current_limit);
2705
2706 /**
2707  * regulator_set_mode - set regulator operating mode
2708  * @regulator: regulator source
2709  * @mode: operating mode - one of the REGULATOR_MODE constants
2710  *
2711  * Set regulator operating mode to increase regulator efficiency or improve
2712  * regulation performance.
2713  *
2714  * NOTE: Regulator system constraints must be set for this regulator before
2715  * calling this function otherwise this call will fail.
2716  */
2717 int regulator_set_mode(struct regulator *regulator, unsigned int mode)
2718 {
2719         struct regulator_dev *rdev = regulator->rdev;
2720         int ret;
2721         int regulator_curr_mode;
2722
2723         mutex_lock(&rdev->mutex);
2724
2725         /* sanity check */
2726         if (!rdev->desc->ops->set_mode) {
2727                 ret = -EINVAL;
2728                 goto out;
2729         }
2730
2731         /* return if the same mode is requested */
2732         if (rdev->desc->ops->get_mode) {
2733                 regulator_curr_mode = rdev->desc->ops->get_mode(rdev);
2734                 if (regulator_curr_mode == mode) {
2735                         ret = 0;
2736                         goto out;
2737                 }
2738         }
2739
2740         /* constraints check */
2741         ret = regulator_mode_constrain(rdev, &mode);
2742         if (ret < 0)
2743                 goto out;
2744
2745         ret = rdev->desc->ops->set_mode(rdev, mode);
2746 out:
2747         mutex_unlock(&rdev->mutex);
2748         return ret;
2749 }
2750 EXPORT_SYMBOL_GPL(regulator_set_mode);
2751
2752 static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
2753 {
2754         int ret;
2755
2756         mutex_lock(&rdev->mutex);
2757
2758         /* sanity check */
2759         if (!rdev->desc->ops->get_mode) {
2760                 ret = -EINVAL;
2761                 goto out;
2762         }
2763
2764         ret = rdev->desc->ops->get_mode(rdev);
2765 out:
2766         mutex_unlock(&rdev->mutex);
2767         return ret;
2768 }
2769
2770 /**
2771  * regulator_get_mode - get regulator operating mode
2772  * @regulator: regulator source
2773  *
2774  * Get the current regulator operating mode.
2775  */
2776 unsigned int regulator_get_mode(struct regulator *regulator)
2777 {
2778         return _regulator_get_mode(regulator->rdev);
2779 }
2780 EXPORT_SYMBOL_GPL(regulator_get_mode);
2781
2782 /**
2783  * regulator_set_optimum_mode - set regulator optimum operating mode
2784  * @regulator: regulator source
2785  * @uA_load: load current
2786  *
2787  * Notifies the regulator core of a new device load. This is then used by
2788  * DRMS (if enabled by constraints) to set the most efficient regulator
2789  * operating mode for the new regulator loading.
2790  *
2791  * Consumer devices notify their supply regulator of the maximum power
2792  * they will require (can be taken from device datasheet in the power
2793  * consumption tables) when they change operational status and hence power
2794  * state. Examples of operational state changes that can affect power
2795  * consumption are :-
2796  *
2797  *    o Device is opened / closed.
2798  *    o Device I/O is about to begin or has just finished.
2799  *    o Device is idling in between work.
2800  *
2801  * This information is also exported via sysfs to userspace.
2802  *
2803  * DRMS will sum the total requested load on the regulator and change
2804  * to the most efficient operating mode if platform constraints allow.
2805  *
2806  * Returns the new regulator mode or error.
2807  */
2808 int regulator_set_optimum_mode(struct regulator *regulator, int uA_load)
2809 {
2810         struct regulator_dev *rdev = regulator->rdev;
2811         struct regulator *consumer;
2812         int ret, output_uV, input_uV = 0, total_uA_load = 0;
2813         unsigned int mode;
2814
2815         if (rdev->supply)
2816                 input_uV = regulator_get_voltage(rdev->supply);
2817
2818         mutex_lock(&rdev->mutex);
2819
2820         /*
2821          * first check to see if we can set modes at all, otherwise just
2822          * tell the consumer everything is OK.
2823          */
2824         regulator->uA_load = uA_load;
2825         ret = regulator_check_drms(rdev);
2826         if (ret < 0) {
2827                 ret = 0;
2828                 goto out;
2829         }
2830
2831         if (!rdev->desc->ops->get_optimum_mode)
2832                 goto out;
2833
2834         /*
2835          * we can actually do this so any errors are indicators of
2836          * potential real failure.
2837          */
2838         ret = -EINVAL;
2839
2840         if (!rdev->desc->ops->set_mode)
2841                 goto out;
2842
2843         /* get output voltage */
2844         output_uV = _regulator_get_voltage(rdev);
2845         if (output_uV <= 0) {
2846                 rdev_err(rdev, "invalid output voltage found\n");
2847                 goto out;
2848         }
2849
2850         /* No supply? Use constraint voltage */
2851         if (input_uV <= 0)
2852                 input_uV = rdev->constraints->input_uV;
2853         if (input_uV <= 0) {
2854                 rdev_err(rdev, "invalid input voltage found\n");
2855                 goto out;
2856         }
2857
2858         /* calc total requested load for this regulator */
2859         list_for_each_entry(consumer, &rdev->consumer_list, list)
2860                 total_uA_load += consumer->uA_load;
2861
2862         mode = rdev->desc->ops->get_optimum_mode(rdev,
2863                                                  input_uV, output_uV,
2864                                                  total_uA_load);
2865         ret = regulator_mode_constrain(rdev, &mode);
2866         if (ret < 0) {
2867                 rdev_err(rdev, "failed to get optimum mode @ %d uA %d -> %d uV\n",
2868                          total_uA_load, input_uV, output_uV);
2869                 goto out;
2870         }
2871
2872         ret = rdev->desc->ops->set_mode(rdev, mode);
2873         if (ret < 0) {
2874                 rdev_err(rdev, "failed to set optimum mode %x\n", mode);
2875                 goto out;
2876         }
2877         ret = mode;
2878 out:
2879         mutex_unlock(&rdev->mutex);
2880         return ret;
2881 }
2882 EXPORT_SYMBOL_GPL(regulator_set_optimum_mode);
2883
2884 /**
2885  * regulator_allow_bypass - allow the regulator to go into bypass mode
2886  *
2887  * @regulator: Regulator to configure
2888  * @enable: enable or disable bypass mode
2889  *
2890  * Allow the regulator to go into bypass mode if all other consumers
2891  * for the regulator also enable bypass mode and the machine
2892  * constraints allow this.  Bypass mode means that the regulator is
2893  * simply passing the input directly to the output with no regulation.
2894  */
2895 int regulator_allow_bypass(struct regulator *regulator, bool enable)
2896 {
2897         struct regulator_dev *rdev = regulator->rdev;
2898         int ret = 0;
2899
2900         if (!rdev->desc->ops->set_bypass)
2901                 return 0;
2902
2903         if (rdev->constraints &&
2904             !(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_BYPASS))
2905                 return 0;
2906
2907         mutex_lock(&rdev->mutex);
2908
2909         if (enable && !regulator->bypass) {
2910                 rdev->bypass_count++;
2911
2912                 if (rdev->bypass_count == rdev->open_count) {
2913                         ret = rdev->desc->ops->set_bypass(rdev, enable);
2914                         if (ret != 0)
2915                                 rdev->bypass_count--;
2916                 }
2917
2918         } else if (!enable && regulator->bypass) {
2919                 rdev->bypass_count--;
2920
2921                 if (rdev->bypass_count != rdev->open_count) {
2922                         ret = rdev->desc->ops->set_bypass(rdev, enable);
2923                         if (ret != 0)
2924                                 rdev->bypass_count++;
2925                 }
2926         }
2927
2928         if (ret == 0)
2929                 regulator->bypass = enable;
2930
2931         mutex_unlock(&rdev->mutex);
2932
2933         return ret;
2934 }
2935 EXPORT_SYMBOL_GPL(regulator_allow_bypass);
2936
2937 /**
2938  * regulator_register_notifier - register regulator event notifier
2939  * @regulator: regulator source
2940  * @nb: notifier block
2941  *
2942  * Register notifier block to receive regulator events.
2943  */
2944 int regulator_register_notifier(struct regulator *regulator,
2945                               struct notifier_block *nb)
2946 {
2947         return blocking_notifier_chain_register(&regulator->rdev->notifier,
2948                                                 nb);
2949 }
2950 EXPORT_SYMBOL_GPL(regulator_register_notifier);
2951
2952 /**
2953  * regulator_unregister_notifier - unregister regulator event notifier
2954  * @regulator: regulator source
2955  * @nb: notifier block
2956  *
2957  * Unregister regulator event notifier block.
2958  */
2959 int regulator_unregister_notifier(struct regulator *regulator,
2960                                 struct notifier_block *nb)
2961 {
2962         return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
2963                                                   nb);
2964 }
2965 EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
2966
2967 /* notify regulator consumers and downstream regulator consumers.
2968  * Note mutex must be held by caller.
2969  */
2970 static void _notifier_call_chain(struct regulator_dev *rdev,
2971                                   unsigned long event, void *data)
2972 {
2973         /* call rdev chain first */
2974         blocking_notifier_call_chain(&rdev->notifier, event, data);
2975 }
2976
2977 /**
2978  * regulator_bulk_get - get multiple regulator consumers
2979  *
2980  * @dev:           Device to supply
2981  * @num_consumers: Number of consumers to register
2982  * @consumers:     Configuration of consumers; clients are stored here.
2983  *
2984  * @return 0 on success, an errno on failure.
2985  *
2986  * This helper function allows drivers to get several regulator
2987  * consumers in one operation.  If any of the regulators cannot be
2988  * acquired then any regulators that were allocated will be freed
2989  * before returning to the caller.
2990  */
2991 int regulator_bulk_get(struct device *dev, int num_consumers,
2992                        struct regulator_bulk_data *consumers)
2993 {
2994         int i;
2995         int ret;
2996
2997         for (i = 0; i < num_consumers; i++)
2998                 consumers[i].consumer = NULL;
2999
3000         for (i = 0; i < num_consumers; i++) {
3001                 consumers[i].consumer = regulator_get(dev,
3002                                                       consumers[i].supply);
3003                 if (IS_ERR(consumers[i].consumer)) {
3004                         ret = PTR_ERR(consumers[i].consumer);
3005                         dev_err(dev, "Failed to get supply '%s': %d\n",
3006                                 consumers[i].supply, ret);
3007                         consumers[i].consumer = NULL;
3008                         goto err;
3009                 }
3010         }
3011
3012         return 0;
3013
3014 err:
3015         while (--i >= 0)
3016                 regulator_put(consumers[i].consumer);
3017
3018         return ret;
3019 }
3020 EXPORT_SYMBOL_GPL(regulator_bulk_get);
3021
3022 static void regulator_bulk_enable_async(void *data, async_cookie_t cookie)
3023 {
3024         struct regulator_bulk_data *bulk = data;
3025
3026         bulk->ret = regulator_enable(bulk->consumer);
3027 }
3028
3029 /**
3030  * regulator_bulk_enable - enable multiple regulator consumers
3031  *
3032  * @num_consumers: Number of consumers
3033  * @consumers:     Consumer data; clients are stored here.
3034  * @return         0 on success, an errno on failure
3035  *
3036  * This convenience API allows consumers to enable multiple regulator
3037  * clients in a single API call.  If any consumers cannot be enabled
3038  * then any others that were enabled will be disabled again prior to
3039  * return.
3040  */
3041 int regulator_bulk_enable(int num_consumers,
3042                           struct regulator_bulk_data *consumers)
3043 {
3044         ASYNC_DOMAIN_EXCLUSIVE(async_domain);
3045         int i;
3046         int ret = 0;
3047
3048         for (i = 0; i < num_consumers; i++) {
3049                 if (consumers[i].consumer->always_on)
3050                         consumers[i].ret = 0;
3051                 else
3052                         async_schedule_domain(regulator_bulk_enable_async,
3053                                               &consumers[i], &async_domain);
3054         }
3055
3056         async_synchronize_full_domain(&async_domain);
3057
3058         /* If any consumer failed we need to unwind any that succeeded */
3059         for (i = 0; i < num_consumers; i++) {
3060                 if (consumers[i].ret != 0) {
3061                         ret = consumers[i].ret;
3062                         goto err;
3063                 }
3064         }
3065
3066         return 0;
3067
3068 err:
3069         for (i = 0; i < num_consumers; i++) {
3070                 if (consumers[i].ret < 0)
3071                         pr_err("Failed to enable %s: %d\n", consumers[i].supply,
3072                                consumers[i].ret);
3073                 else
3074                         regulator_disable(consumers[i].consumer);
3075         }
3076
3077         return ret;
3078 }
3079 EXPORT_SYMBOL_GPL(regulator_bulk_enable);
3080
3081 /**
3082  * regulator_bulk_disable - disable multiple regulator consumers
3083  *
3084  * @num_consumers: Number of consumers
3085  * @consumers:     Consumer data; clients are stored here.
3086  * @return         0 on success, an errno on failure
3087  *
3088  * This convenience API allows consumers to disable multiple regulator
3089  * clients in a single API call.  If any consumers cannot be disabled
3090  * then any others that were disabled will be enabled again prior to
3091  * return.
3092  */
3093 int regulator_bulk_disable(int num_consumers,
3094                            struct regulator_bulk_data *consumers)
3095 {
3096         int i;
3097         int ret, r;
3098
3099         for (i = num_consumers - 1; i >= 0; --i) {
3100                 ret = regulator_disable(consumers[i].consumer);
3101                 if (ret != 0)
3102                         goto err;
3103         }
3104
3105         return 0;
3106
3107 err:
3108         pr_err("Failed to disable %s: %d\n", consumers[i].supply, ret);
3109         for (++i; i < num_consumers; ++i) {
3110                 r = regulator_enable(consumers[i].consumer);
3111                 if (r != 0)
3112                         pr_err("Failed to reename %s: %d\n",
3113                                consumers[i].supply, r);
3114         }
3115
3116         return ret;
3117 }
3118 EXPORT_SYMBOL_GPL(regulator_bulk_disable);
3119
3120 /**
3121  * regulator_bulk_force_disable - force disable multiple regulator consumers
3122  *
3123  * @num_consumers: Number of consumers
3124  * @consumers:     Consumer data; clients are stored here.
3125  * @return         0 on success, an errno on failure
3126  *
3127  * This convenience API allows consumers to forcibly disable multiple regulator
3128  * clients in a single API call.
3129  * NOTE: This should be used for situations when device damage will
3130  * likely occur if the regulators are not disabled (e.g. over temp).
3131  * Although regulator_force_disable function call for some consumers can
3132  * return error numbers, the function is called for all consumers.
3133  */
3134 int regulator_bulk_force_disable(int num_consumers,
3135                            struct regulator_bulk_data *consumers)
3136 {
3137         int i;
3138         int ret;
3139
3140         for (i = 0; i < num_consumers; i++)
3141                 consumers[i].ret =
3142                             regulator_force_disable(consumers[i].consumer);
3143
3144         for (i = 0; i < num_consumers; i++) {
3145                 if (consumers[i].ret != 0) {
3146                         ret = consumers[i].ret;
3147                         goto out;
3148                 }
3149         }
3150
3151         return 0;
3152 out:
3153         return ret;
3154 }
3155 EXPORT_SYMBOL_GPL(regulator_bulk_force_disable);
3156
3157 /**
3158  * regulator_bulk_free - free multiple regulator consumers
3159  *
3160  * @num_consumers: Number of consumers
3161  * @consumers:     Consumer data; clients are stored here.
3162  *
3163  * This convenience API allows consumers to free multiple regulator
3164  * clients in a single API call.
3165  */
3166 void regulator_bulk_free(int num_consumers,
3167                          struct regulator_bulk_data *consumers)
3168 {
3169         int i;
3170
3171         for (i = 0; i < num_consumers; i++) {
3172                 regulator_put(consumers[i].consumer);
3173                 consumers[i].consumer = NULL;
3174         }
3175 }
3176 EXPORT_SYMBOL_GPL(regulator_bulk_free);
3177
3178 /**
3179  * regulator_notifier_call_chain - call regulator event notifier
3180  * @rdev: regulator source
3181  * @event: notifier block
3182  * @data: callback-specific data.
3183  *
3184  * Called by regulator drivers to notify clients a regulator event has
3185  * occurred. We also notify regulator clients downstream.
3186  * Note lock must be held by caller.
3187  */
3188 int regulator_notifier_call_chain(struct regulator_dev *rdev,
3189                                   unsigned long event, void *data)
3190 {
3191         _notifier_call_chain(rdev, event, data);
3192         return NOTIFY_DONE;
3193
3194 }
3195 EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
3196
3197 /**
3198  * regulator_mode_to_status - convert a regulator mode into a status
3199  *
3200  * @mode: Mode to convert
3201  *
3202  * Convert a regulator mode into a status.
3203  */
3204 int regulator_mode_to_status(unsigned int mode)
3205 {
3206         switch (mode) {
3207         case REGULATOR_MODE_FAST:
3208                 return REGULATOR_STATUS_FAST;
3209         case REGULATOR_MODE_NORMAL:
3210                 return REGULATOR_STATUS_NORMAL;
3211         case REGULATOR_MODE_IDLE:
3212                 return REGULATOR_STATUS_IDLE;
3213         case REGULATOR_MODE_STANDBY:
3214                 return REGULATOR_STATUS_STANDBY;
3215         default:
3216                 return REGULATOR_STATUS_UNDEFINED;
3217         }
3218 }
3219 EXPORT_SYMBOL_GPL(regulator_mode_to_status);
3220
3221 /*
3222  * To avoid cluttering sysfs (and memory) with useless state, only
3223  * create attributes that can be meaningfully displayed.
3224  */
3225 static int add_regulator_attributes(struct regulator_dev *rdev)
3226 {
3227         struct device           *dev = &rdev->dev;
3228         struct regulator_ops    *ops = rdev->desc->ops;
3229         int                     status = 0;
3230
3231         /* some attributes need specific methods to be displayed */
3232         if ((ops->get_voltage && ops->get_voltage(rdev) >= 0) ||
3233             (ops->get_voltage_sel && ops->get_voltage_sel(rdev) >= 0) ||
3234             (ops->list_voltage && ops->list_voltage(rdev, 0) >= 0) ||
3235                 (rdev->desc->fixed_uV && (rdev->desc->n_voltages == 1))) {
3236                 status = device_create_file(dev, &dev_attr_microvolts);
3237                 if (status < 0)
3238                         return status;
3239         }
3240         if (ops->get_current_limit) {
3241                 status = device_create_file(dev, &dev_attr_microamps);
3242                 if (status < 0)
3243                         return status;
3244         }
3245         if (ops->get_mode) {
3246                 status = device_create_file(dev, &dev_attr_opmode);
3247                 if (status < 0)
3248                         return status;
3249         }
3250         if (rdev->ena_pin || ops->is_enabled) {
3251                 status = device_create_file(dev, &dev_attr_state);
3252                 if (status < 0)
3253                         return status;
3254         }
3255         if (ops->get_status) {
3256                 status = device_create_file(dev, &dev_attr_status);
3257                 if (status < 0)
3258                         return status;
3259         }
3260         if (ops->get_bypass) {
3261                 status = device_create_file(dev, &dev_attr_bypass);
3262                 if (status < 0)
3263                         return status;
3264         }
3265
3266         /* some attributes are type-specific */
3267         if (rdev->desc->type == REGULATOR_CURRENT) {
3268                 status = device_create_file(dev, &dev_attr_requested_microamps);
3269                 if (status < 0)
3270                         return status;
3271         }
3272
3273         /* all the other attributes exist to support constraints;
3274          * don't show them if there are no constraints, or if the
3275          * relevant supporting methods are missing.
3276          */
3277         if (!rdev->constraints)
3278                 return status;
3279
3280         /* constraints need specific supporting methods */
3281         if (ops->set_voltage || ops->set_voltage_sel) {
3282                 status = device_create_file(dev, &dev_attr_min_microvolts);
3283                 if (status < 0)
3284                         return status;
3285                 status = device_create_file(dev, &dev_attr_max_microvolts);
3286                 if (status < 0)
3287                         return status;
3288         }
3289         if (ops->set_current_limit) {
3290                 status = device_create_file(dev, &dev_attr_min_microamps);
3291                 if (status < 0)
3292                         return status;
3293                 status = device_create_file(dev, &dev_attr_max_microamps);
3294                 if (status < 0)
3295                         return status;
3296         }
3297
3298         status = device_create_file(dev, &dev_attr_suspend_standby_state);
3299         if (status < 0)
3300                 return status;
3301         status = device_create_file(dev, &dev_attr_suspend_mem_state);
3302         if (status < 0)
3303                 return status;
3304         status = device_create_file(dev, &dev_attr_suspend_disk_state);
3305         if (status < 0)
3306                 return status;
3307
3308         if (ops->set_suspend_voltage) {
3309                 status = device_create_file(dev,
3310                                 &dev_attr_suspend_standby_microvolts);
3311                 if (status < 0)
3312                         return status;
3313                 status = device_create_file(dev,
3314                                 &dev_attr_suspend_mem_microvolts);
3315                 if (status < 0)
3316                         return status;
3317                 status = device_create_file(dev,
3318                                 &dev_attr_suspend_disk_microvolts);
3319                 if (status < 0)
3320                         return status;
3321         }
3322
3323         if (ops->set_suspend_mode) {
3324                 status = device_create_file(dev,
3325                                 &dev_attr_suspend_standby_mode);
3326                 if (status < 0)
3327                         return status;
3328                 status = device_create_file(dev,
3329                                 &dev_attr_suspend_mem_mode);
3330                 if (status < 0)
3331                         return status;
3332                 status = device_create_file(dev,
3333                                 &dev_attr_suspend_disk_mode);
3334                 if (status < 0)
3335                         return status;
3336         }
3337
3338         return status;
3339 }
3340
3341 static void rdev_init_debugfs(struct regulator_dev *rdev)
3342 {
3343         rdev->debugfs = debugfs_create_dir(rdev_get_name(rdev), debugfs_root);
3344         if (!rdev->debugfs) {
3345                 rdev_warn(rdev, "Failed to create debugfs directory\n");
3346                 return;
3347         }
3348
3349         debugfs_create_u32("use_count", 0444, rdev->debugfs,
3350                            &rdev->use_count);
3351         debugfs_create_u32("open_count", 0444, rdev->debugfs,
3352                            &rdev->open_count);
3353         debugfs_create_u32("bypass_count", 0444, rdev->debugfs,
3354                            &rdev->bypass_count);
3355 }
3356
3357 /**
3358  * regulator_register - register regulator
3359  * @regulator_desc: regulator to register
3360  * @config: runtime configuration for regulator
3361  *
3362  * Called by regulator drivers to register a regulator.
3363  * Returns a valid pointer to struct regulator_dev on success
3364  * or an ERR_PTR() on error.
3365  */
3366 struct regulator_dev *
3367 regulator_register(const struct regulator_desc *regulator_desc,
3368                    const struct regulator_config *config)
3369 {
3370         const struct regulation_constraints *constraints = NULL;
3371         const struct regulator_init_data *init_data;
3372         static atomic_t regulator_no = ATOMIC_INIT(0);
3373         struct regulator_dev *rdev;
3374         struct device *dev;
3375         int ret, i;
3376         const char *supply = NULL;
3377
3378         if (regulator_desc == NULL || config == NULL)
3379                 return ERR_PTR(-EINVAL);
3380
3381         dev = config->dev;
3382         WARN_ON(!dev);
3383
3384         if (regulator_desc->name == NULL || regulator_desc->ops == NULL)
3385                 return ERR_PTR(-EINVAL);
3386
3387         if (regulator_desc->type != REGULATOR_VOLTAGE &&
3388             regulator_desc->type != REGULATOR_CURRENT)
3389                 return ERR_PTR(-EINVAL);
3390
3391         /* Only one of each should be implemented */
3392         WARN_ON(regulator_desc->ops->get_voltage &&
3393                 regulator_desc->ops->get_voltage_sel);
3394         WARN_ON(regulator_desc->ops->set_voltage &&
3395                 regulator_desc->ops->set_voltage_sel);
3396
3397         /* If we're using selectors we must implement list_voltage. */
3398         if (regulator_desc->ops->get_voltage_sel &&
3399             !regulator_desc->ops->list_voltage) {
3400                 return ERR_PTR(-EINVAL);
3401         }
3402         if (regulator_desc->ops->set_voltage_sel &&
3403             !regulator_desc->ops->list_voltage) {
3404                 return ERR_PTR(-EINVAL);
3405         }
3406
3407         init_data = config->init_data;
3408
3409         rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
3410         if (rdev == NULL)
3411                 return ERR_PTR(-ENOMEM);
3412
3413         mutex_lock(&regulator_list_mutex);
3414
3415         mutex_init(&rdev->mutex);
3416         rdev->reg_data = config->driver_data;
3417         rdev->owner = regulator_desc->owner;
3418         rdev->desc = regulator_desc;
3419         if (config->regmap)
3420                 rdev->regmap = config->regmap;
3421         else if (dev_get_regmap(dev, NULL))
3422                 rdev->regmap = dev_get_regmap(dev, NULL);
3423         else if (dev->parent)
3424                 rdev->regmap = dev_get_regmap(dev->parent, NULL);
3425         INIT_LIST_HEAD(&rdev->consumer_list);
3426         INIT_LIST_HEAD(&rdev->list);
3427         BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
3428         INIT_DELAYED_WORK(&rdev->disable_work, regulator_disable_work);
3429
3430         /* preform any regulator specific init */
3431         if (init_data && init_data->regulator_init) {
3432                 ret = init_data->regulator_init(rdev->reg_data);
3433                 if (ret < 0)
3434                         goto clean;
3435         }
3436
3437         /* register with sysfs */
3438         rdev->dev.class = &regulator_class;
3439         rdev->dev.of_node = config->of_node;
3440         rdev->dev.parent = dev;
3441         dev_set_name(&rdev->dev, "regulator.%d",
3442                      atomic_inc_return(&regulator_no) - 1);
3443         ret = device_register(&rdev->dev);
3444         if (ret != 0) {
3445                 put_device(&rdev->dev);
3446                 goto clean;
3447         }
3448
3449         dev_set_drvdata(&rdev->dev, rdev);
3450
3451         if (config->ena_gpio && gpio_is_valid(config->ena_gpio)) {
3452                 ret = regulator_ena_gpio_request(rdev, config);
3453                 if (ret != 0) {
3454                         rdev_err(rdev, "Failed to request enable GPIO%d: %d\n",
3455                                  config->ena_gpio, ret);
3456                         goto wash;
3457                 }
3458
3459                 if (config->ena_gpio_flags & GPIOF_OUT_INIT_HIGH)
3460                         rdev->ena_gpio_state = 1;
3461
3462                 if (config->ena_gpio_invert)
3463                         rdev->ena_gpio_state = !rdev->ena_gpio_state;
3464         }
3465
3466         /* set regulator constraints */
3467         if (init_data)
3468                 constraints = &init_data->constraints;
3469
3470         ret = set_machine_constraints(rdev, constraints);
3471         if (ret < 0)
3472                 goto scrub;
3473
3474         /* add attributes supported by this regulator */
3475         ret = add_regulator_attributes(rdev);
3476         if (ret < 0)
3477                 goto scrub;
3478
3479         if (init_data && init_data->supply_regulator)
3480                 supply = init_data->supply_regulator;
3481         else if (regulator_desc->supply_name)
3482                 supply = regulator_desc->supply_name;
3483
3484         if (supply) {
3485                 struct regulator_dev *r;
3486
3487                 r = regulator_dev_lookup(dev, supply, &ret);
3488
3489                 if (ret == -ENODEV) {
3490                         /*
3491                          * No supply was specified for this regulator and
3492                          * there will never be one.
3493                          */
3494                         ret = 0;
3495                         goto add_dev;
3496                 } else if (!r) {
3497                         dev_err(dev, "Failed to find supply %s\n", supply);
3498                         ret = -EPROBE_DEFER;
3499                         goto scrub;
3500                 }
3501
3502                 ret = set_supply(rdev, r);
3503                 if (ret < 0)
3504                         goto scrub;
3505
3506                 /* Enable supply if rail is enabled */
3507                 if (_regulator_is_enabled(rdev)) {
3508                         ret = regulator_enable(rdev->supply);
3509                         if (ret < 0)
3510                                 goto scrub;
3511                 }
3512         }
3513
3514 add_dev:
3515         /* add consumers devices */
3516         if (init_data) {
3517                 for (i = 0; i < init_data->num_consumer_supplies; i++) {
3518                         ret = set_consumer_device_supply(rdev,
3519                                 init_data->consumer_supplies[i].dev_name,
3520                                 init_data->consumer_supplies[i].supply);
3521                         if (ret < 0) {
3522                                 dev_err(dev, "Failed to set supply %s\n",
3523                                         init_data->consumer_supplies[i].supply);
3524                                 goto unset_supplies;
3525                         }
3526                 }
3527         }
3528
3529         list_add(&rdev->list, &regulator_list);
3530
3531         rdev_init_debugfs(rdev);
3532 out:
3533         mutex_unlock(&regulator_list_mutex);
3534         return rdev;
3535
3536 unset_supplies:
3537         unset_regulator_supplies(rdev);
3538
3539 scrub:
3540         if (rdev->supply)
3541                 _regulator_put(rdev->supply);
3542         regulator_ena_gpio_free(rdev);
3543         kfree(rdev->constraints);
3544 wash:
3545         device_unregister(&rdev->dev);
3546         /* device core frees rdev */
3547         rdev = ERR_PTR(ret);
3548         goto out;
3549
3550 clean:
3551         kfree(rdev);
3552         rdev = ERR_PTR(ret);
3553         goto out;
3554 }
3555 EXPORT_SYMBOL_GPL(regulator_register);
3556
3557 /**
3558  * regulator_unregister - unregister regulator
3559  * @rdev: regulator to unregister
3560  *
3561  * Called by regulator drivers to unregister a regulator.
3562  */
3563 void regulator_unregister(struct regulator_dev *rdev)
3564 {
3565         if (rdev == NULL)
3566                 return;
3567
3568         if (rdev->supply) {
3569                 while (rdev->use_count--)
3570                         regulator_disable(rdev->supply);
3571                 regulator_put(rdev->supply);
3572         }
3573         mutex_lock(&regulator_list_mutex);
3574         debugfs_remove_recursive(rdev->debugfs);
3575         flush_work(&rdev->disable_work.work);
3576         WARN_ON(rdev->open_count);
3577         unset_regulator_supplies(rdev);
3578         list_del(&rdev->list);
3579         kfree(rdev->constraints);
3580         regulator_ena_gpio_free(rdev);
3581         device_unregister(&rdev->dev);
3582         mutex_unlock(&regulator_list_mutex);
3583 }
3584 EXPORT_SYMBOL_GPL(regulator_unregister);
3585
3586 /**
3587  * regulator_suspend_prepare - prepare regulators for system wide suspend
3588  * @state: system suspend state
3589  *
3590  * Configure each regulator with it's suspend operating parameters for state.
3591  * This will usually be called by machine suspend code prior to supending.
3592  */
3593 int regulator_suspend_prepare(suspend_state_t state)
3594 {
3595         struct regulator_dev *rdev;
3596         int ret = 0;
3597
3598         /* ON is handled by regulator active state */
3599         if (state == PM_SUSPEND_ON)
3600                 return -EINVAL;
3601
3602         mutex_lock(&regulator_list_mutex);
3603         list_for_each_entry(rdev, &regulator_list, list) {
3604
3605                 mutex_lock(&rdev->mutex);
3606                 ret = suspend_prepare(rdev, state);
3607                 mutex_unlock(&rdev->mutex);
3608
3609                 if (ret < 0) {
3610                         rdev_err(rdev, "failed to prepare\n");
3611                         goto out;
3612                 }
3613         }
3614 out:
3615         mutex_unlock(&regulator_list_mutex);
3616         return ret;
3617 }
3618 EXPORT_SYMBOL_GPL(regulator_suspend_prepare);
3619
3620 /**
3621  * regulator_suspend_finish - resume regulators from system wide suspend
3622  *
3623  * Turn on regulators that might be turned off by regulator_suspend_prepare
3624  * and that should be turned on according to the regulators properties.
3625  */
3626 int regulator_suspend_finish(void)
3627 {
3628         struct regulator_dev *rdev;
3629         int ret = 0, error;
3630
3631         mutex_lock(&regulator_list_mutex);
3632         list_for_each_entry(rdev, &regulator_list, list) {
3633                 struct regulator_ops *ops = rdev->desc->ops;
3634
3635                 mutex_lock(&rdev->mutex);
3636                 if ((rdev->use_count > 0  || rdev->constraints->always_on) &&
3637                                 ops->enable) {
3638                         error = ops->enable(rdev);
3639                         if (error)
3640                                 ret = error;
3641                 } else {
3642                         if (!have_full_constraints())
3643                                 goto unlock;
3644                         if (!ops->disable)
3645                                 goto unlock;
3646                         if (!_regulator_is_enabled(rdev))
3647                                 goto unlock;
3648
3649                         error = ops->disable(rdev);
3650                         if (error)
3651                                 ret = error;
3652                 }
3653 unlock:
3654                 mutex_unlock(&rdev->mutex);
3655         }
3656         mutex_unlock(&regulator_list_mutex);
3657         return ret;
3658 }
3659 EXPORT_SYMBOL_GPL(regulator_suspend_finish);
3660
3661 /**
3662  * regulator_has_full_constraints - the system has fully specified constraints
3663  *
3664  * Calling this function will cause the regulator API to disable all
3665  * regulators which have a zero use count and don't have an always_on
3666  * constraint in a late_initcall.
3667  *
3668  * The intention is that this will become the default behaviour in a
3669  * future kernel release so users are encouraged to use this facility
3670  * now.
3671  */
3672 void regulator_has_full_constraints(void)
3673 {
3674         has_full_constraints = 1;
3675 }
3676 EXPORT_SYMBOL_GPL(regulator_has_full_constraints);
3677
3678 /**
3679  * rdev_get_drvdata - get rdev regulator driver data
3680  * @rdev: regulator
3681  *
3682  * Get rdev regulator driver private data. This call can be used in the
3683  * regulator driver context.
3684  */
3685 void *rdev_get_drvdata(struct regulator_dev *rdev)
3686 {
3687         return rdev->reg_data;
3688 }
3689 EXPORT_SYMBOL_GPL(rdev_get_drvdata);
3690
3691 /**
3692  * regulator_get_drvdata - get regulator driver data
3693  * @regulator: regulator
3694  *
3695  * Get regulator driver private data. This call can be used in the consumer
3696  * driver context when non API regulator specific functions need to be called.
3697  */
3698 void *regulator_get_drvdata(struct regulator *regulator)
3699 {
3700         return regulator->rdev->reg_data;
3701 }
3702 EXPORT_SYMBOL_GPL(regulator_get_drvdata);
3703
3704 /**
3705  * regulator_set_drvdata - set regulator driver data
3706  * @regulator: regulator
3707  * @data: data
3708  */
3709 void regulator_set_drvdata(struct regulator *regulator, void *data)
3710 {
3711         regulator->rdev->reg_data = data;
3712 }
3713 EXPORT_SYMBOL_GPL(regulator_set_drvdata);
3714
3715 /**
3716  * regulator_get_id - get regulator ID
3717  * @rdev: regulator
3718  */
3719 int rdev_get_id(struct regulator_dev *rdev)
3720 {
3721         return rdev->desc->id;
3722 }
3723 EXPORT_SYMBOL_GPL(rdev_get_id);
3724
3725 struct device *rdev_get_dev(struct regulator_dev *rdev)
3726 {
3727         return &rdev->dev;
3728 }
3729 EXPORT_SYMBOL_GPL(rdev_get_dev);
3730
3731 void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
3732 {
3733         return reg_init_data->driver_data;
3734 }
3735 EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
3736
3737 #ifdef CONFIG_DEBUG_FS
3738 static ssize_t supply_map_read_file(struct file *file, char __user *user_buf,
3739                                     size_t count, loff_t *ppos)
3740 {
3741         char *buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
3742         ssize_t len, ret = 0;
3743         struct regulator_map *map;
3744
3745         if (!buf)
3746                 return -ENOMEM;
3747
3748         list_for_each_entry(map, &regulator_map_list, list) {
3749                 len = snprintf(buf + ret, PAGE_SIZE - ret,
3750                                "%s -> %s.%s\n",
3751                                rdev_get_name(map->regulator), map->dev_name,
3752                                map->supply);
3753                 if (len >= 0)
3754                         ret += len;
3755                 if (ret > PAGE_SIZE) {
3756                         ret = PAGE_SIZE;
3757                         break;
3758                 }
3759         }
3760
3761         ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
3762
3763         kfree(buf);
3764
3765         return ret;
3766 }
3767 #endif
3768
3769 static const struct file_operations supply_map_fops = {
3770 #ifdef CONFIG_DEBUG_FS
3771         .read = supply_map_read_file,
3772         .llseek = default_llseek,
3773 #endif
3774 };
3775
3776 static int __init regulator_init(void)
3777 {
3778         int ret;
3779
3780         ret = class_register(&regulator_class);
3781
3782         debugfs_root = debugfs_create_dir("regulator", NULL);
3783         if (!debugfs_root)
3784                 pr_warn("regulator: Failed to create debugfs directory\n");
3785
3786         debugfs_create_file("supply_map", 0444, debugfs_root, NULL,
3787                             &supply_map_fops);
3788
3789         regulator_dummy_init();
3790
3791         return ret;
3792 }
3793
3794 /* init early to allow our consumers to complete system booting */
3795 core_initcall(regulator_init);
3796
3797 static int __init regulator_init_complete(void)
3798 {
3799         struct regulator_dev *rdev;
3800         struct regulator_ops *ops;
3801         struct regulation_constraints *c;
3802         int enabled, ret;
3803
3804         /*
3805          * Since DT doesn't provide an idiomatic mechanism for
3806          * enabling full constraints and since it's much more natural
3807          * with DT to provide them just assume that a DT enabled
3808          * system has full constraints.
3809          */
3810         if (of_have_populated_dt())
3811                 has_full_constraints = true;
3812
3813         mutex_lock(&regulator_list_mutex);
3814
3815         /* If we have a full configuration then disable any regulators
3816          * which are not in use or always_on.  This will become the
3817          * default behaviour in the future.
3818          */
3819         list_for_each_entry(rdev, &regulator_list, list) {
3820                 ops = rdev->desc->ops;
3821                 c = rdev->constraints;
3822
3823                 if (!ops->disable || (c && c->always_on))
3824                         continue;
3825
3826                 mutex_lock(&rdev->mutex);
3827
3828                 if (rdev->use_count)
3829                         goto unlock;
3830
3831                 /* If we can't read the status assume it's on. */
3832                 if (ops->is_enabled)
3833                         enabled = ops->is_enabled(rdev);
3834                 else
3835                         enabled = 1;
3836
3837                 if (!enabled)
3838                         goto unlock;
3839
3840                 if (have_full_constraints()) {
3841                         /* We log since this may kill the system if it
3842                          * goes wrong. */
3843                         rdev_info(rdev, "disabling\n");
3844                         ret = ops->disable(rdev);
3845                         if (ret != 0)
3846                                 rdev_err(rdev, "couldn't disable: %d\n", ret);
3847                 } else {
3848                         /* The intention is that in future we will
3849                          * assume that full constraints are provided
3850                          * so warn even if we aren't going to do
3851                          * anything here.
3852                          */
3853                         rdev_warn(rdev, "incomplete constraints, leaving on\n");
3854                 }
3855
3856 unlock:
3857                 mutex_unlock(&rdev->mutex);
3858         }
3859
3860         mutex_unlock(&regulator_list_mutex);
3861
3862         return 0;
3863 }
3864 late_initcall(regulator_init_complete);