Merge remote-tracking branch 'regulator/fix/core' into regulator-linus
[sfrench/cifs-2.6.git] / drivers / regulator / core.c
1 /*
2  * core.c  --  Voltage/Current Regulator framework.
3  *
4  * Copyright 2007, 2008 Wolfson Microelectronics PLC.
5  * Copyright 2008 SlimLogic Ltd.
6  *
7  * Author: Liam Girdwood <lrg@slimlogic.co.uk>
8  *
9  *  This program is free software; you can redistribute  it and/or modify it
10  *  under  the terms of  the GNU General  Public License as published by the
11  *  Free Software Foundation;  either version 2 of the  License, or (at your
12  *  option) any later version.
13  *
14  */
15
16 #include <linux/kernel.h>
17 #include <linux/init.h>
18 #include <linux/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/gpio/consumer.h>
28 #include <linux/of.h>
29 #include <linux/regmap.h>
30 #include <linux/regulator/of_regulator.h>
31 #include <linux/regulator/consumer.h>
32 #include <linux/regulator/driver.h>
33 #include <linux/regulator/machine.h>
34 #include <linux/module.h>
35
36 #define CREATE_TRACE_POINTS
37 #include <trace/events/regulator.h>
38
39 #include "dummy.h"
40 #include "internal.h"
41
42 #define rdev_crit(rdev, fmt, ...)                                       \
43         pr_crit("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
44 #define rdev_err(rdev, fmt, ...)                                        \
45         pr_err("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
46 #define rdev_warn(rdev, fmt, ...)                                       \
47         pr_warn("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
48 #define rdev_info(rdev, fmt, ...)                                       \
49         pr_info("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
50 #define rdev_dbg(rdev, fmt, ...)                                        \
51         pr_debug("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
52
53 static DEFINE_MUTEX(regulator_list_mutex);
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 static struct class regulator_class;
62
63 /*
64  * struct regulator_map
65  *
66  * Used to provide symbolic supply names to devices.
67  */
68 struct regulator_map {
69         struct list_head list;
70         const char *dev_name;   /* The dev_name() for the consumer */
71         const char *supply;
72         struct regulator_dev *regulator;
73 };
74
75 /*
76  * struct regulator_enable_gpio
77  *
78  * Management for shared enable GPIO pin
79  */
80 struct regulator_enable_gpio {
81         struct list_head list;
82         struct gpio_desc *gpiod;
83         u32 enable_count;       /* a number of enabled shared GPIO */
84         u32 request_count;      /* a number of requested shared GPIO */
85         unsigned int ena_gpio_invert:1;
86 };
87
88 /*
89  * struct regulator_supply_alias
90  *
91  * Used to map lookups for a supply onto an alternative device.
92  */
93 struct regulator_supply_alias {
94         struct list_head list;
95         struct device *src_dev;
96         const char *src_supply;
97         struct device *alias_dev;
98         const char *alias_supply;
99 };
100
101 static int _regulator_is_enabled(struct regulator_dev *rdev);
102 static int _regulator_disable(struct regulator_dev *rdev);
103 static int _regulator_get_voltage(struct regulator_dev *rdev);
104 static int _regulator_get_current_limit(struct regulator_dev *rdev);
105 static unsigned int _regulator_get_mode(struct regulator_dev *rdev);
106 static int _notifier_call_chain(struct regulator_dev *rdev,
107                                   unsigned long event, void *data);
108 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
109                                      int min_uV, int max_uV);
110 static struct regulator *create_regulator(struct regulator_dev *rdev,
111                                           struct device *dev,
112                                           const char *supply_name);
113 static void _regulator_put(struct regulator *regulator);
114
115 static struct regulator_dev *dev_to_rdev(struct device *dev)
116 {
117         return container_of(dev, struct regulator_dev, dev);
118 }
119
120 static const char *rdev_get_name(struct regulator_dev *rdev)
121 {
122         if (rdev->constraints && rdev->constraints->name)
123                 return rdev->constraints->name;
124         else if (rdev->desc->name)
125                 return rdev->desc->name;
126         else
127                 return "";
128 }
129
130 static bool have_full_constraints(void)
131 {
132         return has_full_constraints || of_have_populated_dt();
133 }
134
135 static bool regulator_ops_is_valid(struct regulator_dev *rdev, int ops)
136 {
137         if (!rdev->constraints) {
138                 rdev_err(rdev, "no constraints\n");
139                 return false;
140         }
141
142         if (rdev->constraints->valid_ops_mask & ops)
143                 return true;
144
145         return false;
146 }
147
148 static inline struct regulator_dev *rdev_get_supply(struct regulator_dev *rdev)
149 {
150         if (rdev && rdev->supply)
151                 return rdev->supply->rdev;
152
153         return NULL;
154 }
155
156 /**
157  * regulator_lock_supply - lock a regulator and its supplies
158  * @rdev:         regulator source
159  */
160 static void regulator_lock_supply(struct regulator_dev *rdev)
161 {
162         int i;
163
164         for (i = 0; rdev; rdev = rdev_get_supply(rdev), i++)
165                 mutex_lock_nested(&rdev->mutex, i);
166 }
167
168 /**
169  * regulator_unlock_supply - unlock a regulator and its supplies
170  * @rdev:         regulator source
171  */
172 static void regulator_unlock_supply(struct regulator_dev *rdev)
173 {
174         struct regulator *supply;
175
176         while (1) {
177                 mutex_unlock(&rdev->mutex);
178                 supply = rdev->supply;
179
180                 if (!rdev->supply)
181                         return;
182
183                 rdev = supply->rdev;
184         }
185 }
186
187 /**
188  * of_get_regulator - get a regulator device node based on supply name
189  * @dev: Device pointer for the consumer (of regulator) device
190  * @supply: regulator supply name
191  *
192  * Extract the regulator device node corresponding to the supply name.
193  * returns the device node corresponding to the regulator if found, else
194  * returns NULL.
195  */
196 static struct device_node *of_get_regulator(struct device *dev, const char *supply)
197 {
198         struct device_node *regnode = NULL;
199         char prop_name[32]; /* 32 is max size of property name */
200
201         dev_dbg(dev, "Looking up %s-supply from device tree\n", supply);
202
203         snprintf(prop_name, 32, "%s-supply", supply);
204         regnode = of_parse_phandle(dev->of_node, prop_name, 0);
205
206         if (!regnode) {
207                 dev_dbg(dev, "Looking up %s property in node %s failed\n",
208                                 prop_name, dev->of_node->full_name);
209                 return NULL;
210         }
211         return regnode;
212 }
213
214 /* Platform voltage constraint check */
215 static int regulator_check_voltage(struct regulator_dev *rdev,
216                                    int *min_uV, int *max_uV)
217 {
218         BUG_ON(*min_uV > *max_uV);
219
220         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE)) {
221                 rdev_err(rdev, "voltage operation not allowed\n");
222                 return -EPERM;
223         }
224
225         if (*max_uV > rdev->constraints->max_uV)
226                 *max_uV = rdev->constraints->max_uV;
227         if (*min_uV < rdev->constraints->min_uV)
228                 *min_uV = rdev->constraints->min_uV;
229
230         if (*min_uV > *max_uV) {
231                 rdev_err(rdev, "unsupportable voltage range: %d-%duV\n",
232                          *min_uV, *max_uV);
233                 return -EINVAL;
234         }
235
236         return 0;
237 }
238
239 /* Make sure we select a voltage that suits the needs of all
240  * regulator consumers
241  */
242 static int regulator_check_consumers(struct regulator_dev *rdev,
243                                      int *min_uV, int *max_uV)
244 {
245         struct regulator *regulator;
246
247         list_for_each_entry(regulator, &rdev->consumer_list, list) {
248                 /*
249                  * Assume consumers that didn't say anything are OK
250                  * with anything in the constraint range.
251                  */
252                 if (!regulator->min_uV && !regulator->max_uV)
253                         continue;
254
255                 if (*max_uV > regulator->max_uV)
256                         *max_uV = regulator->max_uV;
257                 if (*min_uV < regulator->min_uV)
258                         *min_uV = regulator->min_uV;
259         }
260
261         if (*min_uV > *max_uV) {
262                 rdev_err(rdev, "Restricting voltage, %u-%uuV\n",
263                         *min_uV, *max_uV);
264                 return -EINVAL;
265         }
266
267         return 0;
268 }
269
270 /* current constraint check */
271 static int regulator_check_current_limit(struct regulator_dev *rdev,
272                                         int *min_uA, int *max_uA)
273 {
274         BUG_ON(*min_uA > *max_uA);
275
276         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_CURRENT)) {
277                 rdev_err(rdev, "current operation not allowed\n");
278                 return -EPERM;
279         }
280
281         if (*max_uA > rdev->constraints->max_uA)
282                 *max_uA = rdev->constraints->max_uA;
283         if (*min_uA < rdev->constraints->min_uA)
284                 *min_uA = rdev->constraints->min_uA;
285
286         if (*min_uA > *max_uA) {
287                 rdev_err(rdev, "unsupportable current range: %d-%duA\n",
288                          *min_uA, *max_uA);
289                 return -EINVAL;
290         }
291
292         return 0;
293 }
294
295 /* operating mode constraint check */
296 static int regulator_mode_constrain(struct regulator_dev *rdev,
297                                     unsigned int *mode)
298 {
299         switch (*mode) {
300         case REGULATOR_MODE_FAST:
301         case REGULATOR_MODE_NORMAL:
302         case REGULATOR_MODE_IDLE:
303         case REGULATOR_MODE_STANDBY:
304                 break;
305         default:
306                 rdev_err(rdev, "invalid mode %x specified\n", *mode);
307                 return -EINVAL;
308         }
309
310         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_MODE)) {
311                 rdev_err(rdev, "mode operation not allowed\n");
312                 return -EPERM;
313         }
314
315         /* The modes are bitmasks, the most power hungry modes having
316          * the lowest values. If the requested mode isn't supported
317          * try higher modes. */
318         while (*mode) {
319                 if (rdev->constraints->valid_modes_mask & *mode)
320                         return 0;
321                 *mode /= 2;
322         }
323
324         return -EINVAL;
325 }
326
327 static ssize_t regulator_uV_show(struct device *dev,
328                                 struct device_attribute *attr, char *buf)
329 {
330         struct regulator_dev *rdev = dev_get_drvdata(dev);
331         ssize_t ret;
332
333         mutex_lock(&rdev->mutex);
334         ret = sprintf(buf, "%d\n", _regulator_get_voltage(rdev));
335         mutex_unlock(&rdev->mutex);
336
337         return ret;
338 }
339 static DEVICE_ATTR(microvolts, 0444, regulator_uV_show, NULL);
340
341 static ssize_t regulator_uA_show(struct device *dev,
342                                 struct device_attribute *attr, char *buf)
343 {
344         struct regulator_dev *rdev = dev_get_drvdata(dev);
345
346         return sprintf(buf, "%d\n", _regulator_get_current_limit(rdev));
347 }
348 static DEVICE_ATTR(microamps, 0444, regulator_uA_show, NULL);
349
350 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
351                          char *buf)
352 {
353         struct regulator_dev *rdev = dev_get_drvdata(dev);
354
355         return sprintf(buf, "%s\n", rdev_get_name(rdev));
356 }
357 static DEVICE_ATTR_RO(name);
358
359 static ssize_t regulator_print_opmode(char *buf, int mode)
360 {
361         switch (mode) {
362         case REGULATOR_MODE_FAST:
363                 return sprintf(buf, "fast\n");
364         case REGULATOR_MODE_NORMAL:
365                 return sprintf(buf, "normal\n");
366         case REGULATOR_MODE_IDLE:
367                 return sprintf(buf, "idle\n");
368         case REGULATOR_MODE_STANDBY:
369                 return sprintf(buf, "standby\n");
370         }
371         return sprintf(buf, "unknown\n");
372 }
373
374 static ssize_t regulator_opmode_show(struct device *dev,
375                                     struct device_attribute *attr, char *buf)
376 {
377         struct regulator_dev *rdev = dev_get_drvdata(dev);
378
379         return regulator_print_opmode(buf, _regulator_get_mode(rdev));
380 }
381 static DEVICE_ATTR(opmode, 0444, regulator_opmode_show, NULL);
382
383 static ssize_t regulator_print_state(char *buf, int state)
384 {
385         if (state > 0)
386                 return sprintf(buf, "enabled\n");
387         else if (state == 0)
388                 return sprintf(buf, "disabled\n");
389         else
390                 return sprintf(buf, "unknown\n");
391 }
392
393 static ssize_t regulator_state_show(struct device *dev,
394                                    struct device_attribute *attr, char *buf)
395 {
396         struct regulator_dev *rdev = dev_get_drvdata(dev);
397         ssize_t ret;
398
399         mutex_lock(&rdev->mutex);
400         ret = regulator_print_state(buf, _regulator_is_enabled(rdev));
401         mutex_unlock(&rdev->mutex);
402
403         return ret;
404 }
405 static DEVICE_ATTR(state, 0444, regulator_state_show, NULL);
406
407 static ssize_t regulator_status_show(struct device *dev,
408                                    struct device_attribute *attr, char *buf)
409 {
410         struct regulator_dev *rdev = dev_get_drvdata(dev);
411         int status;
412         char *label;
413
414         status = rdev->desc->ops->get_status(rdev);
415         if (status < 0)
416                 return status;
417
418         switch (status) {
419         case REGULATOR_STATUS_OFF:
420                 label = "off";
421                 break;
422         case REGULATOR_STATUS_ON:
423                 label = "on";
424                 break;
425         case REGULATOR_STATUS_ERROR:
426                 label = "error";
427                 break;
428         case REGULATOR_STATUS_FAST:
429                 label = "fast";
430                 break;
431         case REGULATOR_STATUS_NORMAL:
432                 label = "normal";
433                 break;
434         case REGULATOR_STATUS_IDLE:
435                 label = "idle";
436                 break;
437         case REGULATOR_STATUS_STANDBY:
438                 label = "standby";
439                 break;
440         case REGULATOR_STATUS_BYPASS:
441                 label = "bypass";
442                 break;
443         case REGULATOR_STATUS_UNDEFINED:
444                 label = "undefined";
445                 break;
446         default:
447                 return -ERANGE;
448         }
449
450         return sprintf(buf, "%s\n", label);
451 }
452 static DEVICE_ATTR(status, 0444, regulator_status_show, NULL);
453
454 static ssize_t regulator_min_uA_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_uA);
463 }
464 static DEVICE_ATTR(min_microamps, 0444, regulator_min_uA_show, NULL);
465
466 static ssize_t regulator_max_uA_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_uA);
475 }
476 static DEVICE_ATTR(max_microamps, 0444, regulator_max_uA_show, NULL);
477
478 static ssize_t regulator_min_uV_show(struct device *dev,
479                                     struct device_attribute *attr, char *buf)
480 {
481         struct regulator_dev *rdev = dev_get_drvdata(dev);
482
483         if (!rdev->constraints)
484                 return sprintf(buf, "constraint not defined\n");
485
486         return sprintf(buf, "%d\n", rdev->constraints->min_uV);
487 }
488 static DEVICE_ATTR(min_microvolts, 0444, regulator_min_uV_show, NULL);
489
490 static ssize_t regulator_max_uV_show(struct device *dev,
491                                     struct device_attribute *attr, char *buf)
492 {
493         struct regulator_dev *rdev = dev_get_drvdata(dev);
494
495         if (!rdev->constraints)
496                 return sprintf(buf, "constraint not defined\n");
497
498         return sprintf(buf, "%d\n", rdev->constraints->max_uV);
499 }
500 static DEVICE_ATTR(max_microvolts, 0444, regulator_max_uV_show, NULL);
501
502 static ssize_t regulator_total_uA_show(struct device *dev,
503                                       struct device_attribute *attr, char *buf)
504 {
505         struct regulator_dev *rdev = dev_get_drvdata(dev);
506         struct regulator *regulator;
507         int uA = 0;
508
509         mutex_lock(&rdev->mutex);
510         list_for_each_entry(regulator, &rdev->consumer_list, list)
511                 uA += regulator->uA_load;
512         mutex_unlock(&rdev->mutex);
513         return sprintf(buf, "%d\n", uA);
514 }
515 static DEVICE_ATTR(requested_microamps, 0444, regulator_total_uA_show, NULL);
516
517 static ssize_t num_users_show(struct device *dev, struct device_attribute *attr,
518                               char *buf)
519 {
520         struct regulator_dev *rdev = dev_get_drvdata(dev);
521         return sprintf(buf, "%d\n", rdev->use_count);
522 }
523 static DEVICE_ATTR_RO(num_users);
524
525 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
526                          char *buf)
527 {
528         struct regulator_dev *rdev = dev_get_drvdata(dev);
529
530         switch (rdev->desc->type) {
531         case REGULATOR_VOLTAGE:
532                 return sprintf(buf, "voltage\n");
533         case REGULATOR_CURRENT:
534                 return sprintf(buf, "current\n");
535         }
536         return sprintf(buf, "unknown\n");
537 }
538 static DEVICE_ATTR_RO(type);
539
540 static ssize_t regulator_suspend_mem_uV_show(struct device *dev,
541                                 struct device_attribute *attr, char *buf)
542 {
543         struct regulator_dev *rdev = dev_get_drvdata(dev);
544
545         return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
546 }
547 static DEVICE_ATTR(suspend_mem_microvolts, 0444,
548                 regulator_suspend_mem_uV_show, NULL);
549
550 static ssize_t regulator_suspend_disk_uV_show(struct device *dev,
551                                 struct device_attribute *attr, char *buf)
552 {
553         struct regulator_dev *rdev = dev_get_drvdata(dev);
554
555         return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
556 }
557 static DEVICE_ATTR(suspend_disk_microvolts, 0444,
558                 regulator_suspend_disk_uV_show, NULL);
559
560 static ssize_t regulator_suspend_standby_uV_show(struct device *dev,
561                                 struct device_attribute *attr, char *buf)
562 {
563         struct regulator_dev *rdev = dev_get_drvdata(dev);
564
565         return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
566 }
567 static DEVICE_ATTR(suspend_standby_microvolts, 0444,
568                 regulator_suspend_standby_uV_show, NULL);
569
570 static ssize_t regulator_suspend_mem_mode_show(struct device *dev,
571                                 struct device_attribute *attr, char *buf)
572 {
573         struct regulator_dev *rdev = dev_get_drvdata(dev);
574
575         return regulator_print_opmode(buf,
576                 rdev->constraints->state_mem.mode);
577 }
578 static DEVICE_ATTR(suspend_mem_mode, 0444,
579                 regulator_suspend_mem_mode_show, NULL);
580
581 static ssize_t regulator_suspend_disk_mode_show(struct device *dev,
582                                 struct device_attribute *attr, char *buf)
583 {
584         struct regulator_dev *rdev = dev_get_drvdata(dev);
585
586         return regulator_print_opmode(buf,
587                 rdev->constraints->state_disk.mode);
588 }
589 static DEVICE_ATTR(suspend_disk_mode, 0444,
590                 regulator_suspend_disk_mode_show, NULL);
591
592 static ssize_t regulator_suspend_standby_mode_show(struct device *dev,
593                                 struct device_attribute *attr, char *buf)
594 {
595         struct regulator_dev *rdev = dev_get_drvdata(dev);
596
597         return regulator_print_opmode(buf,
598                 rdev->constraints->state_standby.mode);
599 }
600 static DEVICE_ATTR(suspend_standby_mode, 0444,
601                 regulator_suspend_standby_mode_show, NULL);
602
603 static ssize_t regulator_suspend_mem_state_show(struct device *dev,
604                                    struct device_attribute *attr, char *buf)
605 {
606         struct regulator_dev *rdev = dev_get_drvdata(dev);
607
608         return regulator_print_state(buf,
609                         rdev->constraints->state_mem.enabled);
610 }
611 static DEVICE_ATTR(suspend_mem_state, 0444,
612                 regulator_suspend_mem_state_show, NULL);
613
614 static ssize_t regulator_suspend_disk_state_show(struct device *dev,
615                                    struct device_attribute *attr, char *buf)
616 {
617         struct regulator_dev *rdev = dev_get_drvdata(dev);
618
619         return regulator_print_state(buf,
620                         rdev->constraints->state_disk.enabled);
621 }
622 static DEVICE_ATTR(suspend_disk_state, 0444,
623                 regulator_suspend_disk_state_show, NULL);
624
625 static ssize_t regulator_suspend_standby_state_show(struct device *dev,
626                                    struct device_attribute *attr, char *buf)
627 {
628         struct regulator_dev *rdev = dev_get_drvdata(dev);
629
630         return regulator_print_state(buf,
631                         rdev->constraints->state_standby.enabled);
632 }
633 static DEVICE_ATTR(suspend_standby_state, 0444,
634                 regulator_suspend_standby_state_show, NULL);
635
636 static ssize_t regulator_bypass_show(struct device *dev,
637                                      struct device_attribute *attr, char *buf)
638 {
639         struct regulator_dev *rdev = dev_get_drvdata(dev);
640         const char *report;
641         bool bypass;
642         int ret;
643
644         ret = rdev->desc->ops->get_bypass(rdev, &bypass);
645
646         if (ret != 0)
647                 report = "unknown";
648         else if (bypass)
649                 report = "enabled";
650         else
651                 report = "disabled";
652
653         return sprintf(buf, "%s\n", report);
654 }
655 static DEVICE_ATTR(bypass, 0444,
656                    regulator_bypass_show, NULL);
657
658 /* Calculate the new optimum regulator operating mode based on the new total
659  * consumer load. All locks held by caller */
660 static int 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         lockdep_assert_held_once(&rdev->mutex);
667
668         /*
669          * first check to see if we can set modes at all, otherwise just
670          * tell the consumer everything is OK.
671          */
672         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_DRMS))
673                 return 0;
674
675         if (!rdev->desc->ops->get_optimum_mode &&
676             !rdev->desc->ops->set_load)
677                 return 0;
678
679         if (!rdev->desc->ops->set_mode &&
680             !rdev->desc->ops->set_load)
681                 return -EINVAL;
682
683         /* calc total requested load */
684         list_for_each_entry(sibling, &rdev->consumer_list, list)
685                 current_uA += sibling->uA_load;
686
687         current_uA += rdev->constraints->system_load;
688
689         if (rdev->desc->ops->set_load) {
690                 /* set the optimum mode for our new total regulator load */
691                 err = rdev->desc->ops->set_load(rdev, current_uA);
692                 if (err < 0)
693                         rdev_err(rdev, "failed to set load %d\n", current_uA);
694         } else {
695                 /* get output voltage */
696                 output_uV = _regulator_get_voltage(rdev);
697                 if (output_uV <= 0) {
698                         rdev_err(rdev, "invalid output voltage found\n");
699                         return -EINVAL;
700                 }
701
702                 /* get input voltage */
703                 input_uV = 0;
704                 if (rdev->supply)
705                         input_uV = regulator_get_voltage(rdev->supply);
706                 if (input_uV <= 0)
707                         input_uV = rdev->constraints->input_uV;
708                 if (input_uV <= 0) {
709                         rdev_err(rdev, "invalid input voltage found\n");
710                         return -EINVAL;
711                 }
712
713                 /* now get the optimum mode for our new total regulator load */
714                 mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
715                                                          output_uV, current_uA);
716
717                 /* check the new mode is allowed */
718                 err = regulator_mode_constrain(rdev, &mode);
719                 if (err < 0) {
720                         rdev_err(rdev, "failed to get optimum mode @ %d uA %d -> %d uV\n",
721                                  current_uA, input_uV, output_uV);
722                         return err;
723                 }
724
725                 err = rdev->desc->ops->set_mode(rdev, mode);
726                 if (err < 0)
727                         rdev_err(rdev, "failed to set optimum mode %x\n", mode);
728         }
729
730         return err;
731 }
732
733 static int suspend_set_state(struct regulator_dev *rdev,
734         struct regulator_state *rstate)
735 {
736         int ret = 0;
737
738         /* If we have no suspend mode configration don't set anything;
739          * only warn if the driver implements set_suspend_voltage or
740          * set_suspend_mode callback.
741          */
742         if (!rstate->enabled && !rstate->disabled) {
743                 if (rdev->desc->ops->set_suspend_voltage ||
744                     rdev->desc->ops->set_suspend_mode)
745                         rdev_warn(rdev, "No configuration\n");
746                 return 0;
747         }
748
749         if (rstate->enabled && rstate->disabled) {
750                 rdev_err(rdev, "invalid configuration\n");
751                 return -EINVAL;
752         }
753
754         if (rstate->enabled && rdev->desc->ops->set_suspend_enable)
755                 ret = rdev->desc->ops->set_suspend_enable(rdev);
756         else if (rstate->disabled && rdev->desc->ops->set_suspend_disable)
757                 ret = rdev->desc->ops->set_suspend_disable(rdev);
758         else /* OK if set_suspend_enable or set_suspend_disable is NULL */
759                 ret = 0;
760
761         if (ret < 0) {
762                 rdev_err(rdev, "failed to enabled/disable\n");
763                 return ret;
764         }
765
766         if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
767                 ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
768                 if (ret < 0) {
769                         rdev_err(rdev, "failed to set voltage\n");
770                         return ret;
771                 }
772         }
773
774         if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
775                 ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
776                 if (ret < 0) {
777                         rdev_err(rdev, "failed to set mode\n");
778                         return ret;
779                 }
780         }
781         return ret;
782 }
783
784 /* locks held by caller */
785 static int suspend_prepare(struct regulator_dev *rdev, suspend_state_t state)
786 {
787         if (!rdev->constraints)
788                 return -EINVAL;
789
790         switch (state) {
791         case PM_SUSPEND_STANDBY:
792                 return suspend_set_state(rdev,
793                         &rdev->constraints->state_standby);
794         case PM_SUSPEND_MEM:
795                 return suspend_set_state(rdev,
796                         &rdev->constraints->state_mem);
797         case PM_SUSPEND_MAX:
798                 return suspend_set_state(rdev,
799                         &rdev->constraints->state_disk);
800         default:
801                 return -EINVAL;
802         }
803 }
804
805 static void print_constraints(struct regulator_dev *rdev)
806 {
807         struct regulation_constraints *constraints = rdev->constraints;
808         char buf[160] = "";
809         size_t len = sizeof(buf) - 1;
810         int count = 0;
811         int ret;
812
813         if (constraints->min_uV && constraints->max_uV) {
814                 if (constraints->min_uV == constraints->max_uV)
815                         count += scnprintf(buf + count, len - count, "%d mV ",
816                                            constraints->min_uV / 1000);
817                 else
818                         count += scnprintf(buf + count, len - count,
819                                            "%d <--> %d mV ",
820                                            constraints->min_uV / 1000,
821                                            constraints->max_uV / 1000);
822         }
823
824         if (!constraints->min_uV ||
825             constraints->min_uV != constraints->max_uV) {
826                 ret = _regulator_get_voltage(rdev);
827                 if (ret > 0)
828                         count += scnprintf(buf + count, len - count,
829                                            "at %d mV ", ret / 1000);
830         }
831
832         if (constraints->uV_offset)
833                 count += scnprintf(buf + count, len - count, "%dmV offset ",
834                                    constraints->uV_offset / 1000);
835
836         if (constraints->min_uA && constraints->max_uA) {
837                 if (constraints->min_uA == constraints->max_uA)
838                         count += scnprintf(buf + count, len - count, "%d mA ",
839                                            constraints->min_uA / 1000);
840                 else
841                         count += scnprintf(buf + count, len - count,
842                                            "%d <--> %d mA ",
843                                            constraints->min_uA / 1000,
844                                            constraints->max_uA / 1000);
845         }
846
847         if (!constraints->min_uA ||
848             constraints->min_uA != constraints->max_uA) {
849                 ret = _regulator_get_current_limit(rdev);
850                 if (ret > 0)
851                         count += scnprintf(buf + count, len - count,
852                                            "at %d mA ", ret / 1000);
853         }
854
855         if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
856                 count += scnprintf(buf + count, len - count, "fast ");
857         if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
858                 count += scnprintf(buf + count, len - count, "normal ");
859         if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
860                 count += scnprintf(buf + count, len - count, "idle ");
861         if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
862                 count += scnprintf(buf + count, len - count, "standby");
863
864         if (!count)
865                 scnprintf(buf, len, "no parameters");
866
867         rdev_dbg(rdev, "%s\n", buf);
868
869         if ((constraints->min_uV != constraints->max_uV) &&
870             !regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE))
871                 rdev_warn(rdev,
872                           "Voltage range but no REGULATOR_CHANGE_VOLTAGE\n");
873 }
874
875 static int machine_constraints_voltage(struct regulator_dev *rdev,
876         struct regulation_constraints *constraints)
877 {
878         const struct regulator_ops *ops = rdev->desc->ops;
879         int ret;
880
881         /* do we need to apply the constraint voltage */
882         if (rdev->constraints->apply_uV &&
883             rdev->constraints->min_uV && rdev->constraints->max_uV) {
884                 int target_min, target_max;
885                 int current_uV = _regulator_get_voltage(rdev);
886                 if (current_uV < 0) {
887                         rdev_err(rdev,
888                                  "failed to get the current voltage(%d)\n",
889                                  current_uV);
890                         return current_uV;
891                 }
892
893                 /*
894                  * If we're below the minimum voltage move up to the
895                  * minimum voltage, if we're above the maximum voltage
896                  * then move down to the maximum.
897                  */
898                 target_min = current_uV;
899                 target_max = current_uV;
900
901                 if (current_uV < rdev->constraints->min_uV) {
902                         target_min = rdev->constraints->min_uV;
903                         target_max = rdev->constraints->min_uV;
904                 }
905
906                 if (current_uV > rdev->constraints->max_uV) {
907                         target_min = rdev->constraints->max_uV;
908                         target_max = rdev->constraints->max_uV;
909                 }
910
911                 if (target_min != current_uV || target_max != current_uV) {
912                         rdev_info(rdev, "Bringing %duV into %d-%duV\n",
913                                   current_uV, target_min, target_max);
914                         ret = _regulator_do_set_voltage(
915                                 rdev, target_min, target_max);
916                         if (ret < 0) {
917                                 rdev_err(rdev,
918                                         "failed to apply %d-%duV constraint(%d)\n",
919                                         target_min, target_max, ret);
920                                 return ret;
921                         }
922                 }
923         }
924
925         /* constrain machine-level voltage specs to fit
926          * the actual range supported by this regulator.
927          */
928         if (ops->list_voltage && rdev->desc->n_voltages) {
929                 int     count = rdev->desc->n_voltages;
930                 int     i;
931                 int     min_uV = INT_MAX;
932                 int     max_uV = INT_MIN;
933                 int     cmin = constraints->min_uV;
934                 int     cmax = constraints->max_uV;
935
936                 /* it's safe to autoconfigure fixed-voltage supplies
937                    and the constraints are used by list_voltage. */
938                 if (count == 1 && !cmin) {
939                         cmin = 1;
940                         cmax = INT_MAX;
941                         constraints->min_uV = cmin;
942                         constraints->max_uV = cmax;
943                 }
944
945                 /* voltage constraints are optional */
946                 if ((cmin == 0) && (cmax == 0))
947                         return 0;
948
949                 /* else require explicit machine-level constraints */
950                 if (cmin <= 0 || cmax <= 0 || cmax < cmin) {
951                         rdev_err(rdev, "invalid voltage constraints\n");
952                         return -EINVAL;
953                 }
954
955                 /* initial: [cmin..cmax] valid, [min_uV..max_uV] not */
956                 for (i = 0; i < count; i++) {
957                         int     value;
958
959                         value = ops->list_voltage(rdev, i);
960                         if (value <= 0)
961                                 continue;
962
963                         /* maybe adjust [min_uV..max_uV] */
964                         if (value >= cmin && value < min_uV)
965                                 min_uV = value;
966                         if (value <= cmax && value > max_uV)
967                                 max_uV = value;
968                 }
969
970                 /* final: [min_uV..max_uV] valid iff constraints valid */
971                 if (max_uV < min_uV) {
972                         rdev_err(rdev,
973                                  "unsupportable voltage constraints %u-%uuV\n",
974                                  min_uV, max_uV);
975                         return -EINVAL;
976                 }
977
978                 /* use regulator's subset of machine constraints */
979                 if (constraints->min_uV < min_uV) {
980                         rdev_dbg(rdev, "override min_uV, %d -> %d\n",
981                                  constraints->min_uV, min_uV);
982                         constraints->min_uV = min_uV;
983                 }
984                 if (constraints->max_uV > max_uV) {
985                         rdev_dbg(rdev, "override max_uV, %d -> %d\n",
986                                  constraints->max_uV, max_uV);
987                         constraints->max_uV = max_uV;
988                 }
989         }
990
991         return 0;
992 }
993
994 static int machine_constraints_current(struct regulator_dev *rdev,
995         struct regulation_constraints *constraints)
996 {
997         const struct regulator_ops *ops = rdev->desc->ops;
998         int ret;
999
1000         if (!constraints->min_uA && !constraints->max_uA)
1001                 return 0;
1002
1003         if (constraints->min_uA > constraints->max_uA) {
1004                 rdev_err(rdev, "Invalid current constraints\n");
1005                 return -EINVAL;
1006         }
1007
1008         if (!ops->set_current_limit || !ops->get_current_limit) {
1009                 rdev_warn(rdev, "Operation of current configuration missing\n");
1010                 return 0;
1011         }
1012
1013         /* Set regulator current in constraints range */
1014         ret = ops->set_current_limit(rdev, constraints->min_uA,
1015                         constraints->max_uA);
1016         if (ret < 0) {
1017                 rdev_err(rdev, "Failed to set current constraint, %d\n", ret);
1018                 return ret;
1019         }
1020
1021         return 0;
1022 }
1023
1024 static int _regulator_do_enable(struct regulator_dev *rdev);
1025
1026 /**
1027  * set_machine_constraints - sets regulator constraints
1028  * @rdev: regulator source
1029  * @constraints: constraints to apply
1030  *
1031  * Allows platform initialisation code to define and constrain
1032  * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
1033  * Constraints *must* be set by platform code in order for some
1034  * regulator operations to proceed i.e. set_voltage, set_current_limit,
1035  * set_mode.
1036  */
1037 static int set_machine_constraints(struct regulator_dev *rdev,
1038         const struct regulation_constraints *constraints)
1039 {
1040         int ret = 0;
1041         const struct regulator_ops *ops = rdev->desc->ops;
1042
1043         if (constraints)
1044                 rdev->constraints = kmemdup(constraints, sizeof(*constraints),
1045                                             GFP_KERNEL);
1046         else
1047                 rdev->constraints = kzalloc(sizeof(*constraints),
1048                                             GFP_KERNEL);
1049         if (!rdev->constraints)
1050                 return -ENOMEM;
1051
1052         ret = machine_constraints_voltage(rdev, rdev->constraints);
1053         if (ret != 0)
1054                 return ret;
1055
1056         ret = machine_constraints_current(rdev, rdev->constraints);
1057         if (ret != 0)
1058                 return ret;
1059
1060         if (rdev->constraints->ilim_uA && ops->set_input_current_limit) {
1061                 ret = ops->set_input_current_limit(rdev,
1062                                                    rdev->constraints->ilim_uA);
1063                 if (ret < 0) {
1064                         rdev_err(rdev, "failed to set input limit\n");
1065                         return ret;
1066                 }
1067         }
1068
1069         /* do we need to setup our suspend state */
1070         if (rdev->constraints->initial_state) {
1071                 ret = suspend_prepare(rdev, rdev->constraints->initial_state);
1072                 if (ret < 0) {
1073                         rdev_err(rdev, "failed to set suspend state\n");
1074                         return ret;
1075                 }
1076         }
1077
1078         if (rdev->constraints->initial_mode) {
1079                 if (!ops->set_mode) {
1080                         rdev_err(rdev, "no set_mode operation\n");
1081                         return -EINVAL;
1082                 }
1083
1084                 ret = ops->set_mode(rdev, rdev->constraints->initial_mode);
1085                 if (ret < 0) {
1086                         rdev_err(rdev, "failed to set initial mode: %d\n", ret);
1087                         return ret;
1088                 }
1089         }
1090
1091         /* If the constraints say the regulator should be on at this point
1092          * and we have control then make sure it is enabled.
1093          */
1094         if (rdev->constraints->always_on || rdev->constraints->boot_on) {
1095                 ret = _regulator_do_enable(rdev);
1096                 if (ret < 0 && ret != -EINVAL) {
1097                         rdev_err(rdev, "failed to enable\n");
1098                         return ret;
1099                 }
1100         }
1101
1102         if ((rdev->constraints->ramp_delay || rdev->constraints->ramp_disable)
1103                 && ops->set_ramp_delay) {
1104                 ret = ops->set_ramp_delay(rdev, rdev->constraints->ramp_delay);
1105                 if (ret < 0) {
1106                         rdev_err(rdev, "failed to set ramp_delay\n");
1107                         return ret;
1108                 }
1109         }
1110
1111         if (rdev->constraints->pull_down && ops->set_pull_down) {
1112                 ret = ops->set_pull_down(rdev);
1113                 if (ret < 0) {
1114                         rdev_err(rdev, "failed to set pull down\n");
1115                         return ret;
1116                 }
1117         }
1118
1119         if (rdev->constraints->soft_start && ops->set_soft_start) {
1120                 ret = ops->set_soft_start(rdev);
1121                 if (ret < 0) {
1122                         rdev_err(rdev, "failed to set soft start\n");
1123                         return ret;
1124                 }
1125         }
1126
1127         if (rdev->constraints->over_current_protection
1128                 && ops->set_over_current_protection) {
1129                 ret = ops->set_over_current_protection(rdev);
1130                 if (ret < 0) {
1131                         rdev_err(rdev, "failed to set over current protection\n");
1132                         return ret;
1133                 }
1134         }
1135
1136         if (rdev->constraints->active_discharge && ops->set_active_discharge) {
1137                 bool ad_state = (rdev->constraints->active_discharge ==
1138                               REGULATOR_ACTIVE_DISCHARGE_ENABLE) ? true : false;
1139
1140                 ret = ops->set_active_discharge(rdev, ad_state);
1141                 if (ret < 0) {
1142                         rdev_err(rdev, "failed to set active discharge\n");
1143                         return ret;
1144                 }
1145         }
1146
1147         print_constraints(rdev);
1148         return 0;
1149 }
1150
1151 /**
1152  * set_supply - set regulator supply regulator
1153  * @rdev: regulator name
1154  * @supply_rdev: supply regulator name
1155  *
1156  * Called by platform initialisation code to set the supply regulator for this
1157  * regulator. This ensures that a regulators supply will also be enabled by the
1158  * core if it's child is enabled.
1159  */
1160 static int set_supply(struct regulator_dev *rdev,
1161                       struct regulator_dev *supply_rdev)
1162 {
1163         int err;
1164
1165         rdev_info(rdev, "supplied by %s\n", rdev_get_name(supply_rdev));
1166
1167         if (!try_module_get(supply_rdev->owner))
1168                 return -ENODEV;
1169
1170         rdev->supply = create_regulator(supply_rdev, &rdev->dev, "SUPPLY");
1171         if (rdev->supply == NULL) {
1172                 err = -ENOMEM;
1173                 return err;
1174         }
1175         supply_rdev->open_count++;
1176
1177         return 0;
1178 }
1179
1180 /**
1181  * set_consumer_device_supply - Bind a regulator to a symbolic supply
1182  * @rdev:         regulator source
1183  * @consumer_dev_name: dev_name() string for device supply applies to
1184  * @supply:       symbolic name for supply
1185  *
1186  * Allows platform initialisation code to map physical regulator
1187  * sources to symbolic names for supplies for use by devices.  Devices
1188  * should use these symbolic names to request regulators, avoiding the
1189  * need to provide board-specific regulator names as platform data.
1190  */
1191 static int set_consumer_device_supply(struct regulator_dev *rdev,
1192                                       const char *consumer_dev_name,
1193                                       const char *supply)
1194 {
1195         struct regulator_map *node;
1196         int has_dev;
1197
1198         if (supply == NULL)
1199                 return -EINVAL;
1200
1201         if (consumer_dev_name != NULL)
1202                 has_dev = 1;
1203         else
1204                 has_dev = 0;
1205
1206         list_for_each_entry(node, &regulator_map_list, list) {
1207                 if (node->dev_name && consumer_dev_name) {
1208                         if (strcmp(node->dev_name, consumer_dev_name) != 0)
1209                                 continue;
1210                 } else if (node->dev_name || consumer_dev_name) {
1211                         continue;
1212                 }
1213
1214                 if (strcmp(node->supply, supply) != 0)
1215                         continue;
1216
1217                 pr_debug("%s: %s/%s is '%s' supply; fail %s/%s\n",
1218                          consumer_dev_name,
1219                          dev_name(&node->regulator->dev),
1220                          node->regulator->desc->name,
1221                          supply,
1222                          dev_name(&rdev->dev), rdev_get_name(rdev));
1223                 return -EBUSY;
1224         }
1225
1226         node = kzalloc(sizeof(struct regulator_map), GFP_KERNEL);
1227         if (node == NULL)
1228                 return -ENOMEM;
1229
1230         node->regulator = rdev;
1231         node->supply = supply;
1232
1233         if (has_dev) {
1234                 node->dev_name = kstrdup(consumer_dev_name, GFP_KERNEL);
1235                 if (node->dev_name == NULL) {
1236                         kfree(node);
1237                         return -ENOMEM;
1238                 }
1239         }
1240
1241         list_add(&node->list, &regulator_map_list);
1242         return 0;
1243 }
1244
1245 static void unset_regulator_supplies(struct regulator_dev *rdev)
1246 {
1247         struct regulator_map *node, *n;
1248
1249         list_for_each_entry_safe(node, n, &regulator_map_list, list) {
1250                 if (rdev == node->regulator) {
1251                         list_del(&node->list);
1252                         kfree(node->dev_name);
1253                         kfree(node);
1254                 }
1255         }
1256 }
1257
1258 #ifdef CONFIG_DEBUG_FS
1259 static ssize_t constraint_flags_read_file(struct file *file,
1260                                           char __user *user_buf,
1261                                           size_t count, loff_t *ppos)
1262 {
1263         const struct regulator *regulator = file->private_data;
1264         const struct regulation_constraints *c = regulator->rdev->constraints;
1265         char *buf;
1266         ssize_t ret;
1267
1268         if (!c)
1269                 return 0;
1270
1271         buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
1272         if (!buf)
1273                 return -ENOMEM;
1274
1275         ret = snprintf(buf, PAGE_SIZE,
1276                         "always_on: %u\n"
1277                         "boot_on: %u\n"
1278                         "apply_uV: %u\n"
1279                         "ramp_disable: %u\n"
1280                         "soft_start: %u\n"
1281                         "pull_down: %u\n"
1282                         "over_current_protection: %u\n",
1283                         c->always_on,
1284                         c->boot_on,
1285                         c->apply_uV,
1286                         c->ramp_disable,
1287                         c->soft_start,
1288                         c->pull_down,
1289                         c->over_current_protection);
1290
1291         ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
1292         kfree(buf);
1293
1294         return ret;
1295 }
1296
1297 #endif
1298
1299 static const struct file_operations constraint_flags_fops = {
1300 #ifdef CONFIG_DEBUG_FS
1301         .open = simple_open,
1302         .read = constraint_flags_read_file,
1303         .llseek = default_llseek,
1304 #endif
1305 };
1306
1307 #define REG_STR_SIZE    64
1308
1309 static struct regulator *create_regulator(struct regulator_dev *rdev,
1310                                           struct device *dev,
1311                                           const char *supply_name)
1312 {
1313         struct regulator *regulator;
1314         char buf[REG_STR_SIZE];
1315         int err, size;
1316
1317         regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
1318         if (regulator == NULL)
1319                 return NULL;
1320
1321         mutex_lock(&rdev->mutex);
1322         regulator->rdev = rdev;
1323         list_add(&regulator->list, &rdev->consumer_list);
1324
1325         if (dev) {
1326                 regulator->dev = dev;
1327
1328                 /* Add a link to the device sysfs entry */
1329                 size = snprintf(buf, REG_STR_SIZE, "%s-%s",
1330                                 dev->kobj.name, supply_name);
1331                 if (size >= REG_STR_SIZE)
1332                         goto overflow_err;
1333
1334                 regulator->supply_name = kstrdup(buf, GFP_KERNEL);
1335                 if (regulator->supply_name == NULL)
1336                         goto overflow_err;
1337
1338                 err = sysfs_create_link_nowarn(&rdev->dev.kobj, &dev->kobj,
1339                                         buf);
1340                 if (err) {
1341                         rdev_dbg(rdev, "could not add device link %s err %d\n",
1342                                   dev->kobj.name, err);
1343                         /* non-fatal */
1344                 }
1345         } else {
1346                 regulator->supply_name = kstrdup_const(supply_name, GFP_KERNEL);
1347                 if (regulator->supply_name == NULL)
1348                         goto overflow_err;
1349         }
1350
1351         regulator->debugfs = debugfs_create_dir(regulator->supply_name,
1352                                                 rdev->debugfs);
1353         if (!regulator->debugfs) {
1354                 rdev_dbg(rdev, "Failed to create debugfs directory\n");
1355         } else {
1356                 debugfs_create_u32("uA_load", 0444, regulator->debugfs,
1357                                    &regulator->uA_load);
1358                 debugfs_create_u32("min_uV", 0444, regulator->debugfs,
1359                                    &regulator->min_uV);
1360                 debugfs_create_u32("max_uV", 0444, regulator->debugfs,
1361                                    &regulator->max_uV);
1362                 debugfs_create_file("constraint_flags", 0444,
1363                                     regulator->debugfs, regulator,
1364                                     &constraint_flags_fops);
1365         }
1366
1367         /*
1368          * Check now if the regulator is an always on regulator - if
1369          * it is then we don't need to do nearly so much work for
1370          * enable/disable calls.
1371          */
1372         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_STATUS) &&
1373             _regulator_is_enabled(rdev))
1374                 regulator->always_on = true;
1375
1376         mutex_unlock(&rdev->mutex);
1377         return regulator;
1378 overflow_err:
1379         list_del(&regulator->list);
1380         kfree(regulator);
1381         mutex_unlock(&rdev->mutex);
1382         return NULL;
1383 }
1384
1385 static int _regulator_get_enable_time(struct regulator_dev *rdev)
1386 {
1387         if (rdev->constraints && rdev->constraints->enable_time)
1388                 return rdev->constraints->enable_time;
1389         if (!rdev->desc->ops->enable_time)
1390                 return rdev->desc->enable_time;
1391         return rdev->desc->ops->enable_time(rdev);
1392 }
1393
1394 static struct regulator_supply_alias *regulator_find_supply_alias(
1395                 struct device *dev, const char *supply)
1396 {
1397         struct regulator_supply_alias *map;
1398
1399         list_for_each_entry(map, &regulator_supply_alias_list, list)
1400                 if (map->src_dev == dev && strcmp(map->src_supply, supply) == 0)
1401                         return map;
1402
1403         return NULL;
1404 }
1405
1406 static void regulator_supply_alias(struct device **dev, const char **supply)
1407 {
1408         struct regulator_supply_alias *map;
1409
1410         map = regulator_find_supply_alias(*dev, *supply);
1411         if (map) {
1412                 dev_dbg(*dev, "Mapping supply %s to %s,%s\n",
1413                                 *supply, map->alias_supply,
1414                                 dev_name(map->alias_dev));
1415                 *dev = map->alias_dev;
1416                 *supply = map->alias_supply;
1417         }
1418 }
1419
1420 static int of_node_match(struct device *dev, const void *data)
1421 {
1422         return dev->of_node == data;
1423 }
1424
1425 static struct regulator_dev *of_find_regulator_by_node(struct device_node *np)
1426 {
1427         struct device *dev;
1428
1429         dev = class_find_device(&regulator_class, NULL, np, of_node_match);
1430
1431         return dev ? dev_to_rdev(dev) : NULL;
1432 }
1433
1434 static int regulator_match(struct device *dev, const void *data)
1435 {
1436         struct regulator_dev *r = dev_to_rdev(dev);
1437
1438         return strcmp(rdev_get_name(r), data) == 0;
1439 }
1440
1441 static struct regulator_dev *regulator_lookup_by_name(const char *name)
1442 {
1443         struct device *dev;
1444
1445         dev = class_find_device(&regulator_class, NULL, name, regulator_match);
1446
1447         return dev ? dev_to_rdev(dev) : NULL;
1448 }
1449
1450 /**
1451  * regulator_dev_lookup - lookup a regulator device.
1452  * @dev: device for regulator "consumer".
1453  * @supply: Supply name or regulator ID.
1454  *
1455  * If successful, returns a struct regulator_dev that corresponds to the name
1456  * @supply and with the embedded struct device refcount incremented by one.
1457  * The refcount must be dropped by calling put_device().
1458  * On failure one of the following ERR-PTR-encoded values is returned:
1459  * -ENODEV if lookup fails permanently, -EPROBE_DEFER if lookup could succeed
1460  * in the future.
1461  */
1462 static struct regulator_dev *regulator_dev_lookup(struct device *dev,
1463                                                   const char *supply)
1464 {
1465         struct regulator_dev *r = NULL;
1466         struct device_node *node;
1467         struct regulator_map *map;
1468         const char *devname = NULL;
1469
1470         regulator_supply_alias(&dev, &supply);
1471
1472         /* first do a dt based lookup */
1473         if (dev && dev->of_node) {
1474                 node = of_get_regulator(dev, supply);
1475                 if (node) {
1476                         r = of_find_regulator_by_node(node);
1477                         if (r)
1478                                 return r;
1479
1480                         /*
1481                          * We have a node, but there is no device.
1482                          * assume it has not registered yet.
1483                          */
1484                         return ERR_PTR(-EPROBE_DEFER);
1485                 }
1486         }
1487
1488         /* if not found, try doing it non-dt way */
1489         if (dev)
1490                 devname = dev_name(dev);
1491
1492         mutex_lock(&regulator_list_mutex);
1493         list_for_each_entry(map, &regulator_map_list, list) {
1494                 /* If the mapping has a device set up it must match */
1495                 if (map->dev_name &&
1496                     (!devname || strcmp(map->dev_name, devname)))
1497                         continue;
1498
1499                 if (strcmp(map->supply, supply) == 0 &&
1500                     get_device(&map->regulator->dev)) {
1501                         r = map->regulator;
1502                         break;
1503                 }
1504         }
1505         mutex_unlock(&regulator_list_mutex);
1506
1507         if (r)
1508                 return r;
1509
1510         r = regulator_lookup_by_name(supply);
1511         if (r)
1512                 return r;
1513
1514         return ERR_PTR(-ENODEV);
1515 }
1516
1517 static int regulator_resolve_supply(struct regulator_dev *rdev)
1518 {
1519         struct regulator_dev *r;
1520         struct device *dev = rdev->dev.parent;
1521         int ret;
1522
1523         /* No supply to resovle? */
1524         if (!rdev->supply_name)
1525                 return 0;
1526
1527         /* Supply already resolved? */
1528         if (rdev->supply)
1529                 return 0;
1530
1531         r = regulator_dev_lookup(dev, rdev->supply_name);
1532         if (IS_ERR(r)) {
1533                 ret = PTR_ERR(r);
1534
1535                 /* Did the lookup explicitly defer for us? */
1536                 if (ret == -EPROBE_DEFER)
1537                         return ret;
1538
1539                 if (have_full_constraints()) {
1540                         r = dummy_regulator_rdev;
1541                         get_device(&r->dev);
1542                 } else {
1543                         dev_err(dev, "Failed to resolve %s-supply for %s\n",
1544                                 rdev->supply_name, rdev->desc->name);
1545                         return -EPROBE_DEFER;
1546                 }
1547         }
1548
1549         /*
1550          * If the supply's parent device is not the same as the
1551          * regulator's parent device, then ensure the parent device
1552          * is bound before we resolve the supply, in case the parent
1553          * device get probe deferred and unregisters the supply.
1554          */
1555         if (r->dev.parent && r->dev.parent != rdev->dev.parent) {
1556                 if (!device_is_bound(r->dev.parent)) {
1557                         put_device(&r->dev);
1558                         return -EPROBE_DEFER;
1559                 }
1560         }
1561
1562         /* Recursively resolve the supply of the supply */
1563         ret = regulator_resolve_supply(r);
1564         if (ret < 0) {
1565                 put_device(&r->dev);
1566                 return ret;
1567         }
1568
1569         ret = set_supply(rdev, r);
1570         if (ret < 0) {
1571                 put_device(&r->dev);
1572                 return ret;
1573         }
1574
1575         /* Cascade always-on state to supply */
1576         if (_regulator_is_enabled(rdev)) {
1577                 ret = regulator_enable(rdev->supply);
1578                 if (ret < 0) {
1579                         _regulator_put(rdev->supply);
1580                         rdev->supply = NULL;
1581                         return ret;
1582                 }
1583         }
1584
1585         return 0;
1586 }
1587
1588 /* Internal regulator request function */
1589 struct regulator *_regulator_get(struct device *dev, const char *id,
1590                                  enum regulator_get_type get_type)
1591 {
1592         struct regulator_dev *rdev;
1593         struct regulator *regulator;
1594         const char *devname = dev ? dev_name(dev) : "deviceless";
1595         int ret;
1596
1597         if (get_type >= MAX_GET_TYPE) {
1598                 dev_err(dev, "invalid type %d in %s\n", get_type, __func__);
1599                 return ERR_PTR(-EINVAL);
1600         }
1601
1602         if (id == NULL) {
1603                 pr_err("get() with no identifier\n");
1604                 return ERR_PTR(-EINVAL);
1605         }
1606
1607         rdev = regulator_dev_lookup(dev, id);
1608         if (IS_ERR(rdev)) {
1609                 ret = PTR_ERR(rdev);
1610
1611                 /*
1612                  * If regulator_dev_lookup() fails with error other
1613                  * than -ENODEV our job here is done, we simply return it.
1614                  */
1615                 if (ret != -ENODEV)
1616                         return ERR_PTR(ret);
1617
1618                 if (!have_full_constraints()) {
1619                         dev_warn(dev,
1620                                  "incomplete constraints, dummy supplies not allowed\n");
1621                         return ERR_PTR(-ENODEV);
1622                 }
1623
1624                 switch (get_type) {
1625                 case NORMAL_GET:
1626                         /*
1627                          * Assume that a regulator is physically present and
1628                          * enabled, even if it isn't hooked up, and just
1629                          * provide a dummy.
1630                          */
1631                         dev_warn(dev,
1632                                  "%s supply %s not found, using dummy regulator\n",
1633                                  devname, id);
1634                         rdev = dummy_regulator_rdev;
1635                         get_device(&rdev->dev);
1636                         break;
1637
1638                 case EXCLUSIVE_GET:
1639                         dev_warn(dev,
1640                                  "dummy supplies not allowed for exclusive requests\n");
1641                         /* fall through */
1642
1643                 default:
1644                         return ERR_PTR(-ENODEV);
1645                 }
1646         }
1647
1648         if (rdev->exclusive) {
1649                 regulator = ERR_PTR(-EPERM);
1650                 put_device(&rdev->dev);
1651                 return regulator;
1652         }
1653
1654         if (get_type == EXCLUSIVE_GET && rdev->open_count) {
1655                 regulator = ERR_PTR(-EBUSY);
1656                 put_device(&rdev->dev);
1657                 return regulator;
1658         }
1659
1660         ret = regulator_resolve_supply(rdev);
1661         if (ret < 0) {
1662                 regulator = ERR_PTR(ret);
1663                 put_device(&rdev->dev);
1664                 return regulator;
1665         }
1666
1667         if (!try_module_get(rdev->owner)) {
1668                 regulator = ERR_PTR(-EPROBE_DEFER);
1669                 put_device(&rdev->dev);
1670                 return regulator;
1671         }
1672
1673         regulator = create_regulator(rdev, dev, id);
1674         if (regulator == NULL) {
1675                 regulator = ERR_PTR(-ENOMEM);
1676                 put_device(&rdev->dev);
1677                 module_put(rdev->owner);
1678                 return regulator;
1679         }
1680
1681         rdev->open_count++;
1682         if (get_type == EXCLUSIVE_GET) {
1683                 rdev->exclusive = 1;
1684
1685                 ret = _regulator_is_enabled(rdev);
1686                 if (ret > 0)
1687                         rdev->use_count = 1;
1688                 else
1689                         rdev->use_count = 0;
1690         }
1691
1692         return regulator;
1693 }
1694
1695 /**
1696  * regulator_get - lookup and obtain a reference to a regulator.
1697  * @dev: device for regulator "consumer"
1698  * @id: Supply name or regulator ID.
1699  *
1700  * Returns a struct regulator corresponding to the regulator producer,
1701  * or IS_ERR() condition containing errno.
1702  *
1703  * Use of supply names configured via regulator_set_device_supply() is
1704  * strongly encouraged.  It is recommended that the supply name used
1705  * should match the name used for the supply and/or the relevant
1706  * device pins in the datasheet.
1707  */
1708 struct regulator *regulator_get(struct device *dev, const char *id)
1709 {
1710         return _regulator_get(dev, id, NORMAL_GET);
1711 }
1712 EXPORT_SYMBOL_GPL(regulator_get);
1713
1714 /**
1715  * regulator_get_exclusive - obtain exclusive access to a regulator.
1716  * @dev: device for regulator "consumer"
1717  * @id: Supply name or regulator ID.
1718  *
1719  * Returns a struct regulator corresponding to the regulator producer,
1720  * or IS_ERR() condition containing errno.  Other consumers will be
1721  * unable to obtain this regulator while this reference is held and the
1722  * use count for the regulator will be initialised to reflect the current
1723  * state of the regulator.
1724  *
1725  * This is intended for use by consumers which cannot tolerate shared
1726  * use of the regulator such as those which need to force the
1727  * regulator off for correct operation of the hardware they are
1728  * controlling.
1729  *
1730  * Use of supply names configured via regulator_set_device_supply() is
1731  * strongly encouraged.  It is recommended that the supply name used
1732  * should match the name used for the supply and/or the relevant
1733  * device pins in the datasheet.
1734  */
1735 struct regulator *regulator_get_exclusive(struct device *dev, const char *id)
1736 {
1737         return _regulator_get(dev, id, EXCLUSIVE_GET);
1738 }
1739 EXPORT_SYMBOL_GPL(regulator_get_exclusive);
1740
1741 /**
1742  * regulator_get_optional - obtain optional access to a regulator.
1743  * @dev: device for regulator "consumer"
1744  * @id: Supply name or regulator ID.
1745  *
1746  * Returns a struct regulator corresponding to the regulator producer,
1747  * or IS_ERR() condition containing errno.
1748  *
1749  * This is intended for use by consumers for devices which can have
1750  * some supplies unconnected in normal use, such as some MMC devices.
1751  * It can allow the regulator core to provide stub supplies for other
1752  * supplies requested using normal regulator_get() calls without
1753  * disrupting the operation of drivers that can handle absent
1754  * supplies.
1755  *
1756  * Use of supply names configured via regulator_set_device_supply() is
1757  * strongly encouraged.  It is recommended that the supply name used
1758  * should match the name used for the supply and/or the relevant
1759  * device pins in the datasheet.
1760  */
1761 struct regulator *regulator_get_optional(struct device *dev, const char *id)
1762 {
1763         return _regulator_get(dev, id, OPTIONAL_GET);
1764 }
1765 EXPORT_SYMBOL_GPL(regulator_get_optional);
1766
1767 /* regulator_list_mutex lock held by regulator_put() */
1768 static void _regulator_put(struct regulator *regulator)
1769 {
1770         struct regulator_dev *rdev;
1771
1772         if (IS_ERR_OR_NULL(regulator))
1773                 return;
1774
1775         lockdep_assert_held_once(&regulator_list_mutex);
1776
1777         rdev = regulator->rdev;
1778
1779         debugfs_remove_recursive(regulator->debugfs);
1780
1781         /* remove any sysfs entries */
1782         if (regulator->dev)
1783                 sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
1784         mutex_lock(&rdev->mutex);
1785         list_del(&regulator->list);
1786
1787         rdev->open_count--;
1788         rdev->exclusive = 0;
1789         put_device(&rdev->dev);
1790         mutex_unlock(&rdev->mutex);
1791
1792         kfree_const(regulator->supply_name);
1793         kfree(regulator);
1794
1795         module_put(rdev->owner);
1796 }
1797
1798 /**
1799  * regulator_put - "free" the regulator source
1800  * @regulator: regulator source
1801  *
1802  * Note: drivers must ensure that all regulator_enable calls made on this
1803  * regulator source are balanced by regulator_disable calls prior to calling
1804  * this function.
1805  */
1806 void regulator_put(struct regulator *regulator)
1807 {
1808         mutex_lock(&regulator_list_mutex);
1809         _regulator_put(regulator);
1810         mutex_unlock(&regulator_list_mutex);
1811 }
1812 EXPORT_SYMBOL_GPL(regulator_put);
1813
1814 /**
1815  * regulator_register_supply_alias - Provide device alias for supply lookup
1816  *
1817  * @dev: device that will be given as the regulator "consumer"
1818  * @id: Supply name or regulator ID
1819  * @alias_dev: device that should be used to lookup the supply
1820  * @alias_id: Supply name or regulator ID that should be used to lookup the
1821  * supply
1822  *
1823  * All lookups for id on dev will instead be conducted for alias_id on
1824  * alias_dev.
1825  */
1826 int regulator_register_supply_alias(struct device *dev, const char *id,
1827                                     struct device *alias_dev,
1828                                     const char *alias_id)
1829 {
1830         struct regulator_supply_alias *map;
1831
1832         map = regulator_find_supply_alias(dev, id);
1833         if (map)
1834                 return -EEXIST;
1835
1836         map = kzalloc(sizeof(struct regulator_supply_alias), GFP_KERNEL);
1837         if (!map)
1838                 return -ENOMEM;
1839
1840         map->src_dev = dev;
1841         map->src_supply = id;
1842         map->alias_dev = alias_dev;
1843         map->alias_supply = alias_id;
1844
1845         list_add(&map->list, &regulator_supply_alias_list);
1846
1847         pr_info("Adding alias for supply %s,%s -> %s,%s\n",
1848                 id, dev_name(dev), alias_id, dev_name(alias_dev));
1849
1850         return 0;
1851 }
1852 EXPORT_SYMBOL_GPL(regulator_register_supply_alias);
1853
1854 /**
1855  * regulator_unregister_supply_alias - Remove device alias
1856  *
1857  * @dev: device that will be given as the regulator "consumer"
1858  * @id: Supply name or regulator ID
1859  *
1860  * Remove a lookup alias if one exists for id on dev.
1861  */
1862 void regulator_unregister_supply_alias(struct device *dev, const char *id)
1863 {
1864         struct regulator_supply_alias *map;
1865
1866         map = regulator_find_supply_alias(dev, id);
1867         if (map) {
1868                 list_del(&map->list);
1869                 kfree(map);
1870         }
1871 }
1872 EXPORT_SYMBOL_GPL(regulator_unregister_supply_alias);
1873
1874 /**
1875  * regulator_bulk_register_supply_alias - register multiple aliases
1876  *
1877  * @dev: device that will be given as the regulator "consumer"
1878  * @id: List of supply names or regulator IDs
1879  * @alias_dev: device that should be used to lookup the supply
1880  * @alias_id: List of supply names or regulator IDs that should be used to
1881  * lookup the supply
1882  * @num_id: Number of aliases to register
1883  *
1884  * @return 0 on success, an errno on failure.
1885  *
1886  * This helper function allows drivers to register several supply
1887  * aliases in one operation.  If any of the aliases cannot be
1888  * registered any aliases that were registered will be removed
1889  * before returning to the caller.
1890  */
1891 int regulator_bulk_register_supply_alias(struct device *dev,
1892                                          const char *const *id,
1893                                          struct device *alias_dev,
1894                                          const char *const *alias_id,
1895                                          int num_id)
1896 {
1897         int i;
1898         int ret;
1899
1900         for (i = 0; i < num_id; ++i) {
1901                 ret = regulator_register_supply_alias(dev, id[i], alias_dev,
1902                                                       alias_id[i]);
1903                 if (ret < 0)
1904                         goto err;
1905         }
1906
1907         return 0;
1908
1909 err:
1910         dev_err(dev,
1911                 "Failed to create supply alias %s,%s -> %s,%s\n",
1912                 id[i], dev_name(dev), alias_id[i], dev_name(alias_dev));
1913
1914         while (--i >= 0)
1915                 regulator_unregister_supply_alias(dev, id[i]);
1916
1917         return ret;
1918 }
1919 EXPORT_SYMBOL_GPL(regulator_bulk_register_supply_alias);
1920
1921 /**
1922  * regulator_bulk_unregister_supply_alias - unregister multiple aliases
1923  *
1924  * @dev: device that will be given as the regulator "consumer"
1925  * @id: List of supply names or regulator IDs
1926  * @num_id: Number of aliases to unregister
1927  *
1928  * This helper function allows drivers to unregister several supply
1929  * aliases in one operation.
1930  */
1931 void regulator_bulk_unregister_supply_alias(struct device *dev,
1932                                             const char *const *id,
1933                                             int num_id)
1934 {
1935         int i;
1936
1937         for (i = 0; i < num_id; ++i)
1938                 regulator_unregister_supply_alias(dev, id[i]);
1939 }
1940 EXPORT_SYMBOL_GPL(regulator_bulk_unregister_supply_alias);
1941
1942
1943 /* Manage enable GPIO list. Same GPIO pin can be shared among regulators */
1944 static int regulator_ena_gpio_request(struct regulator_dev *rdev,
1945                                 const struct regulator_config *config)
1946 {
1947         struct regulator_enable_gpio *pin;
1948         struct gpio_desc *gpiod;
1949         int ret;
1950
1951         gpiod = gpio_to_desc(config->ena_gpio);
1952
1953         list_for_each_entry(pin, &regulator_ena_gpio_list, list) {
1954                 if (pin->gpiod == gpiod) {
1955                         rdev_dbg(rdev, "GPIO %d is already used\n",
1956                                 config->ena_gpio);
1957                         goto update_ena_gpio_to_rdev;
1958                 }
1959         }
1960
1961         ret = gpio_request_one(config->ena_gpio,
1962                                 GPIOF_DIR_OUT | config->ena_gpio_flags,
1963                                 rdev_get_name(rdev));
1964         if (ret)
1965                 return ret;
1966
1967         pin = kzalloc(sizeof(struct regulator_enable_gpio), GFP_KERNEL);
1968         if (pin == NULL) {
1969                 gpio_free(config->ena_gpio);
1970                 return -ENOMEM;
1971         }
1972
1973         pin->gpiod = gpiod;
1974         pin->ena_gpio_invert = config->ena_gpio_invert;
1975         list_add(&pin->list, &regulator_ena_gpio_list);
1976
1977 update_ena_gpio_to_rdev:
1978         pin->request_count++;
1979         rdev->ena_pin = pin;
1980         return 0;
1981 }
1982
1983 static void regulator_ena_gpio_free(struct regulator_dev *rdev)
1984 {
1985         struct regulator_enable_gpio *pin, *n;
1986
1987         if (!rdev->ena_pin)
1988                 return;
1989
1990         /* Free the GPIO only in case of no use */
1991         list_for_each_entry_safe(pin, n, &regulator_ena_gpio_list, list) {
1992                 if (pin->gpiod == rdev->ena_pin->gpiod) {
1993                         if (pin->request_count <= 1) {
1994                                 pin->request_count = 0;
1995                                 gpiod_put(pin->gpiod);
1996                                 list_del(&pin->list);
1997                                 kfree(pin);
1998                                 rdev->ena_pin = NULL;
1999                                 return;
2000                         } else {
2001                                 pin->request_count--;
2002                         }
2003                 }
2004         }
2005 }
2006
2007 /**
2008  * regulator_ena_gpio_ctrl - balance enable_count of each GPIO and actual GPIO pin control
2009  * @rdev: regulator_dev structure
2010  * @enable: enable GPIO at initial use?
2011  *
2012  * GPIO is enabled in case of initial use. (enable_count is 0)
2013  * GPIO is disabled when it is not shared any more. (enable_count <= 1)
2014  */
2015 static int regulator_ena_gpio_ctrl(struct regulator_dev *rdev, bool enable)
2016 {
2017         struct regulator_enable_gpio *pin = rdev->ena_pin;
2018
2019         if (!pin)
2020                 return -EINVAL;
2021
2022         if (enable) {
2023                 /* Enable GPIO at initial use */
2024                 if (pin->enable_count == 0)
2025                         gpiod_set_value_cansleep(pin->gpiod,
2026                                                  !pin->ena_gpio_invert);
2027
2028                 pin->enable_count++;
2029         } else {
2030                 if (pin->enable_count > 1) {
2031                         pin->enable_count--;
2032                         return 0;
2033                 }
2034
2035                 /* Disable GPIO if not used */
2036                 if (pin->enable_count <= 1) {
2037                         gpiod_set_value_cansleep(pin->gpiod,
2038                                                  pin->ena_gpio_invert);
2039                         pin->enable_count = 0;
2040                 }
2041         }
2042
2043         return 0;
2044 }
2045
2046 /**
2047  * _regulator_enable_delay - a delay helper function
2048  * @delay: time to delay in microseconds
2049  *
2050  * Delay for the requested amount of time as per the guidelines in:
2051  *
2052  *     Documentation/timers/timers-howto.txt
2053  *
2054  * The assumption here is that regulators will never be enabled in
2055  * atomic context and therefore sleeping functions can be used.
2056  */
2057 static void _regulator_enable_delay(unsigned int delay)
2058 {
2059         unsigned int ms = delay / 1000;
2060         unsigned int us = delay % 1000;
2061
2062         if (ms > 0) {
2063                 /*
2064                  * For small enough values, handle super-millisecond
2065                  * delays in the usleep_range() call below.
2066                  */
2067                 if (ms < 20)
2068                         us += ms * 1000;
2069                 else
2070                         msleep(ms);
2071         }
2072
2073         /*
2074          * Give the scheduler some room to coalesce with any other
2075          * wakeup sources. For delays shorter than 10 us, don't even
2076          * bother setting up high-resolution timers and just busy-
2077          * loop.
2078          */
2079         if (us >= 10)
2080                 usleep_range(us, us + 100);
2081         else
2082                 udelay(us);
2083 }
2084
2085 static int _regulator_do_enable(struct regulator_dev *rdev)
2086 {
2087         int ret, delay;
2088
2089         /* Query before enabling in case configuration dependent.  */
2090         ret = _regulator_get_enable_time(rdev);
2091         if (ret >= 0) {
2092                 delay = ret;
2093         } else {
2094                 rdev_warn(rdev, "enable_time() failed: %d\n", ret);
2095                 delay = 0;
2096         }
2097
2098         trace_regulator_enable(rdev_get_name(rdev));
2099
2100         if (rdev->desc->off_on_delay) {
2101                 /* if needed, keep a distance of off_on_delay from last time
2102                  * this regulator was disabled.
2103                  */
2104                 unsigned long start_jiffy = jiffies;
2105                 unsigned long intended, max_delay, remaining;
2106
2107                 max_delay = usecs_to_jiffies(rdev->desc->off_on_delay);
2108                 intended = rdev->last_off_jiffy + max_delay;
2109
2110                 if (time_before(start_jiffy, intended)) {
2111                         /* calc remaining jiffies to deal with one-time
2112                          * timer wrapping.
2113                          * in case of multiple timer wrapping, either it can be
2114                          * detected by out-of-range remaining, or it cannot be
2115                          * detected and we gets a panelty of
2116                          * _regulator_enable_delay().
2117                          */
2118                         remaining = intended - start_jiffy;
2119                         if (remaining <= max_delay)
2120                                 _regulator_enable_delay(
2121                                                 jiffies_to_usecs(remaining));
2122                 }
2123         }
2124
2125         if (rdev->ena_pin) {
2126                 if (!rdev->ena_gpio_state) {
2127                         ret = regulator_ena_gpio_ctrl(rdev, true);
2128                         if (ret < 0)
2129                                 return ret;
2130                         rdev->ena_gpio_state = 1;
2131                 }
2132         } else if (rdev->desc->ops->enable) {
2133                 ret = rdev->desc->ops->enable(rdev);
2134                 if (ret < 0)
2135                         return ret;
2136         } else {
2137                 return -EINVAL;
2138         }
2139
2140         /* Allow the regulator to ramp; it would be useful to extend
2141          * this for bulk operations so that the regulators can ramp
2142          * together.  */
2143         trace_regulator_enable_delay(rdev_get_name(rdev));
2144
2145         _regulator_enable_delay(delay);
2146
2147         trace_regulator_enable_complete(rdev_get_name(rdev));
2148
2149         return 0;
2150 }
2151
2152 /* locks held by regulator_enable() */
2153 static int _regulator_enable(struct regulator_dev *rdev)
2154 {
2155         int ret;
2156
2157         lockdep_assert_held_once(&rdev->mutex);
2158
2159         /* check voltage and requested load before enabling */
2160         if (regulator_ops_is_valid(rdev, REGULATOR_CHANGE_DRMS))
2161                 drms_uA_update(rdev);
2162
2163         if (rdev->use_count == 0) {
2164                 /* The regulator may on if it's not switchable or left on */
2165                 ret = _regulator_is_enabled(rdev);
2166                 if (ret == -EINVAL || ret == 0) {
2167                         if (!regulator_ops_is_valid(rdev,
2168                                         REGULATOR_CHANGE_STATUS))
2169                                 return -EPERM;
2170
2171                         ret = _regulator_do_enable(rdev);
2172                         if (ret < 0)
2173                                 return ret;
2174
2175                         _notifier_call_chain(rdev, REGULATOR_EVENT_ENABLE,
2176                                              NULL);
2177                 } else if (ret < 0) {
2178                         rdev_err(rdev, "is_enabled() failed: %d\n", ret);
2179                         return ret;
2180                 }
2181                 /* Fallthrough on positive return values - already enabled */
2182         }
2183
2184         rdev->use_count++;
2185
2186         return 0;
2187 }
2188
2189 /**
2190  * regulator_enable - enable regulator output
2191  * @regulator: regulator source
2192  *
2193  * Request that the regulator be enabled with the regulator output at
2194  * the predefined voltage or current value.  Calls to regulator_enable()
2195  * must be balanced with calls to regulator_disable().
2196  *
2197  * NOTE: the output value can be set by other drivers, boot loader or may be
2198  * hardwired in the regulator.
2199  */
2200 int regulator_enable(struct regulator *regulator)
2201 {
2202         struct regulator_dev *rdev = regulator->rdev;
2203         int ret = 0;
2204
2205         if (regulator->always_on)
2206                 return 0;
2207
2208         if (rdev->supply) {
2209                 ret = regulator_enable(rdev->supply);
2210                 if (ret != 0)
2211                         return ret;
2212         }
2213
2214         mutex_lock(&rdev->mutex);
2215         ret = _regulator_enable(rdev);
2216         mutex_unlock(&rdev->mutex);
2217
2218         if (ret != 0 && rdev->supply)
2219                 regulator_disable(rdev->supply);
2220
2221         return ret;
2222 }
2223 EXPORT_SYMBOL_GPL(regulator_enable);
2224
2225 static int _regulator_do_disable(struct regulator_dev *rdev)
2226 {
2227         int ret;
2228
2229         trace_regulator_disable(rdev_get_name(rdev));
2230
2231         if (rdev->ena_pin) {
2232                 if (rdev->ena_gpio_state) {
2233                         ret = regulator_ena_gpio_ctrl(rdev, false);
2234                         if (ret < 0)
2235                                 return ret;
2236                         rdev->ena_gpio_state = 0;
2237                 }
2238
2239         } else if (rdev->desc->ops->disable) {
2240                 ret = rdev->desc->ops->disable(rdev);
2241                 if (ret != 0)
2242                         return ret;
2243         }
2244
2245         /* cares about last_off_jiffy only if off_on_delay is required by
2246          * device.
2247          */
2248         if (rdev->desc->off_on_delay)
2249                 rdev->last_off_jiffy = jiffies;
2250
2251         trace_regulator_disable_complete(rdev_get_name(rdev));
2252
2253         return 0;
2254 }
2255
2256 /* locks held by regulator_disable() */
2257 static int _regulator_disable(struct regulator_dev *rdev)
2258 {
2259         int ret = 0;
2260
2261         lockdep_assert_held_once(&rdev->mutex);
2262
2263         if (WARN(rdev->use_count <= 0,
2264                  "unbalanced disables for %s\n", rdev_get_name(rdev)))
2265                 return -EIO;
2266
2267         /* are we the last user and permitted to disable ? */
2268         if (rdev->use_count == 1 &&
2269             (rdev->constraints && !rdev->constraints->always_on)) {
2270
2271                 /* we are last user */
2272                 if (regulator_ops_is_valid(rdev, REGULATOR_CHANGE_STATUS)) {
2273                         ret = _notifier_call_chain(rdev,
2274                                                    REGULATOR_EVENT_PRE_DISABLE,
2275                                                    NULL);
2276                         if (ret & NOTIFY_STOP_MASK)
2277                                 return -EINVAL;
2278
2279                         ret = _regulator_do_disable(rdev);
2280                         if (ret < 0) {
2281                                 rdev_err(rdev, "failed to disable\n");
2282                                 _notifier_call_chain(rdev,
2283                                                 REGULATOR_EVENT_ABORT_DISABLE,
2284                                                 NULL);
2285                                 return ret;
2286                         }
2287                         _notifier_call_chain(rdev, REGULATOR_EVENT_DISABLE,
2288                                         NULL);
2289                 }
2290
2291                 rdev->use_count = 0;
2292         } else if (rdev->use_count > 1) {
2293                 if (regulator_ops_is_valid(rdev, REGULATOR_CHANGE_DRMS))
2294                         drms_uA_update(rdev);
2295
2296                 rdev->use_count--;
2297         }
2298
2299         return ret;
2300 }
2301
2302 /**
2303  * regulator_disable - disable regulator output
2304  * @regulator: regulator source
2305  *
2306  * Disable the regulator output voltage or current.  Calls to
2307  * regulator_enable() must be balanced with calls to
2308  * regulator_disable().
2309  *
2310  * NOTE: this will only disable the regulator output if no other consumer
2311  * devices have it enabled, the regulator device supports disabling and
2312  * machine constraints permit this operation.
2313  */
2314 int regulator_disable(struct regulator *regulator)
2315 {
2316         struct regulator_dev *rdev = regulator->rdev;
2317         int ret = 0;
2318
2319         if (regulator->always_on)
2320                 return 0;
2321
2322         mutex_lock(&rdev->mutex);
2323         ret = _regulator_disable(rdev);
2324         mutex_unlock(&rdev->mutex);
2325
2326         if (ret == 0 && rdev->supply)
2327                 regulator_disable(rdev->supply);
2328
2329         return ret;
2330 }
2331 EXPORT_SYMBOL_GPL(regulator_disable);
2332
2333 /* locks held by regulator_force_disable() */
2334 static int _regulator_force_disable(struct regulator_dev *rdev)
2335 {
2336         int ret = 0;
2337
2338         lockdep_assert_held_once(&rdev->mutex);
2339
2340         ret = _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
2341                         REGULATOR_EVENT_PRE_DISABLE, NULL);
2342         if (ret & NOTIFY_STOP_MASK)
2343                 return -EINVAL;
2344
2345         ret = _regulator_do_disable(rdev);
2346         if (ret < 0) {
2347                 rdev_err(rdev, "failed to force disable\n");
2348                 _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
2349                                 REGULATOR_EVENT_ABORT_DISABLE, NULL);
2350                 return ret;
2351         }
2352
2353         _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
2354                         REGULATOR_EVENT_DISABLE, NULL);
2355
2356         return 0;
2357 }
2358
2359 /**
2360  * regulator_force_disable - force disable regulator output
2361  * @regulator: regulator source
2362  *
2363  * Forcibly disable the regulator output voltage or current.
2364  * NOTE: this *will* disable the regulator output even if other consumer
2365  * devices have it enabled. This should be used for situations when device
2366  * damage will likely occur if the regulator is not disabled (e.g. over temp).
2367  */
2368 int regulator_force_disable(struct regulator *regulator)
2369 {
2370         struct regulator_dev *rdev = regulator->rdev;
2371         int ret;
2372
2373         mutex_lock(&rdev->mutex);
2374         regulator->uA_load = 0;
2375         ret = _regulator_force_disable(regulator->rdev);
2376         mutex_unlock(&rdev->mutex);
2377
2378         if (rdev->supply)
2379                 while (rdev->open_count--)
2380                         regulator_disable(rdev->supply);
2381
2382         return ret;
2383 }
2384 EXPORT_SYMBOL_GPL(regulator_force_disable);
2385
2386 static void regulator_disable_work(struct work_struct *work)
2387 {
2388         struct regulator_dev *rdev = container_of(work, struct regulator_dev,
2389                                                   disable_work.work);
2390         int count, i, ret;
2391
2392         mutex_lock(&rdev->mutex);
2393
2394         BUG_ON(!rdev->deferred_disables);
2395
2396         count = rdev->deferred_disables;
2397         rdev->deferred_disables = 0;
2398
2399         /*
2400          * Workqueue functions queue the new work instance while the previous
2401          * work instance is being processed. Cancel the queued work instance
2402          * as the work instance under processing does the job of the queued
2403          * work instance.
2404          */
2405         cancel_delayed_work(&rdev->disable_work);
2406
2407         for (i = 0; i < count; i++) {
2408                 ret = _regulator_disable(rdev);
2409                 if (ret != 0)
2410                         rdev_err(rdev, "Deferred disable failed: %d\n", ret);
2411         }
2412
2413         mutex_unlock(&rdev->mutex);
2414
2415         if (rdev->supply) {
2416                 for (i = 0; i < count; i++) {
2417                         ret = regulator_disable(rdev->supply);
2418                         if (ret != 0) {
2419                                 rdev_err(rdev,
2420                                          "Supply disable failed: %d\n", ret);
2421                         }
2422                 }
2423         }
2424 }
2425
2426 /**
2427  * regulator_disable_deferred - disable regulator output with delay
2428  * @regulator: regulator source
2429  * @ms: miliseconds until the regulator is disabled
2430  *
2431  * Execute regulator_disable() on the regulator after a delay.  This
2432  * is intended for use with devices that require some time to quiesce.
2433  *
2434  * NOTE: this will only disable the regulator output if no other consumer
2435  * devices have it enabled, the regulator device supports disabling and
2436  * machine constraints permit this operation.
2437  */
2438 int regulator_disable_deferred(struct regulator *regulator, int ms)
2439 {
2440         struct regulator_dev *rdev = regulator->rdev;
2441
2442         if (regulator->always_on)
2443                 return 0;
2444
2445         if (!ms)
2446                 return regulator_disable(regulator);
2447
2448         mutex_lock(&rdev->mutex);
2449         rdev->deferred_disables++;
2450         mod_delayed_work(system_power_efficient_wq, &rdev->disable_work,
2451                          msecs_to_jiffies(ms));
2452         mutex_unlock(&rdev->mutex);
2453
2454         return 0;
2455 }
2456 EXPORT_SYMBOL_GPL(regulator_disable_deferred);
2457
2458 static int _regulator_is_enabled(struct regulator_dev *rdev)
2459 {
2460         /* A GPIO control always takes precedence */
2461         if (rdev->ena_pin)
2462                 return rdev->ena_gpio_state;
2463
2464         /* If we don't know then assume that the regulator is always on */
2465         if (!rdev->desc->ops->is_enabled)
2466                 return 1;
2467
2468         return rdev->desc->ops->is_enabled(rdev);
2469 }
2470
2471 static int _regulator_list_voltage(struct regulator *regulator,
2472                                     unsigned selector, int lock)
2473 {
2474         struct regulator_dev *rdev = regulator->rdev;
2475         const struct regulator_ops *ops = rdev->desc->ops;
2476         int ret;
2477
2478         if (rdev->desc->fixed_uV && rdev->desc->n_voltages == 1 && !selector)
2479                 return rdev->desc->fixed_uV;
2480
2481         if (ops->list_voltage) {
2482                 if (selector >= rdev->desc->n_voltages)
2483                         return -EINVAL;
2484                 if (lock)
2485                         mutex_lock(&rdev->mutex);
2486                 ret = ops->list_voltage(rdev, selector);
2487                 if (lock)
2488                         mutex_unlock(&rdev->mutex);
2489         } else if (rdev->is_switch && rdev->supply) {
2490                 ret = _regulator_list_voltage(rdev->supply, selector, lock);
2491         } else {
2492                 return -EINVAL;
2493         }
2494
2495         if (ret > 0) {
2496                 if (ret < rdev->constraints->min_uV)
2497                         ret = 0;
2498                 else if (ret > rdev->constraints->max_uV)
2499                         ret = 0;
2500         }
2501
2502         return ret;
2503 }
2504
2505 /**
2506  * regulator_is_enabled - is the regulator output enabled
2507  * @regulator: regulator source
2508  *
2509  * Returns positive if the regulator driver backing the source/client
2510  * has requested that the device be enabled, zero if it hasn't, else a
2511  * negative errno code.
2512  *
2513  * Note that the device backing this regulator handle can have multiple
2514  * users, so it might be enabled even if regulator_enable() was never
2515  * called for this particular source.
2516  */
2517 int regulator_is_enabled(struct regulator *regulator)
2518 {
2519         int ret;
2520
2521         if (regulator->always_on)
2522                 return 1;
2523
2524         mutex_lock(&regulator->rdev->mutex);
2525         ret = _regulator_is_enabled(regulator->rdev);
2526         mutex_unlock(&regulator->rdev->mutex);
2527
2528         return ret;
2529 }
2530 EXPORT_SYMBOL_GPL(regulator_is_enabled);
2531
2532 /**
2533  * regulator_count_voltages - count regulator_list_voltage() selectors
2534  * @regulator: regulator source
2535  *
2536  * Returns number of selectors, or negative errno.  Selectors are
2537  * numbered starting at zero, and typically correspond to bitfields
2538  * in hardware registers.
2539  */
2540 int regulator_count_voltages(struct regulator *regulator)
2541 {
2542         struct regulator_dev    *rdev = regulator->rdev;
2543
2544         if (rdev->desc->n_voltages)
2545                 return rdev->desc->n_voltages;
2546
2547         if (!rdev->is_switch || !rdev->supply)
2548                 return -EINVAL;
2549
2550         return regulator_count_voltages(rdev->supply);
2551 }
2552 EXPORT_SYMBOL_GPL(regulator_count_voltages);
2553
2554 /**
2555  * regulator_list_voltage - enumerate supported voltages
2556  * @regulator: regulator source
2557  * @selector: identify voltage to list
2558  * Context: can sleep
2559  *
2560  * Returns a voltage that can be passed to @regulator_set_voltage(),
2561  * zero if this selector code can't be used on this system, or a
2562  * negative errno.
2563  */
2564 int regulator_list_voltage(struct regulator *regulator, unsigned selector)
2565 {
2566         return _regulator_list_voltage(regulator, selector, 1);
2567 }
2568 EXPORT_SYMBOL_GPL(regulator_list_voltage);
2569
2570 /**
2571  * regulator_get_regmap - get the regulator's register map
2572  * @regulator: regulator source
2573  *
2574  * Returns the register map for the given regulator, or an ERR_PTR value
2575  * if the regulator doesn't use regmap.
2576  */
2577 struct regmap *regulator_get_regmap(struct regulator *regulator)
2578 {
2579         struct regmap *map = regulator->rdev->regmap;
2580
2581         return map ? map : ERR_PTR(-EOPNOTSUPP);
2582 }
2583
2584 /**
2585  * regulator_get_hardware_vsel_register - get the HW voltage selector register
2586  * @regulator: regulator source
2587  * @vsel_reg: voltage selector register, output parameter
2588  * @vsel_mask: mask for voltage selector bitfield, output parameter
2589  *
2590  * Returns the hardware register offset and bitmask used for setting the
2591  * regulator voltage. This might be useful when configuring voltage-scaling
2592  * hardware or firmware that can make I2C requests behind the kernel's back,
2593  * for example.
2594  *
2595  * On success, the output parameters @vsel_reg and @vsel_mask are filled in
2596  * and 0 is returned, otherwise a negative errno is returned.
2597  */
2598 int regulator_get_hardware_vsel_register(struct regulator *regulator,
2599                                          unsigned *vsel_reg,
2600                                          unsigned *vsel_mask)
2601 {
2602         struct regulator_dev *rdev = regulator->rdev;
2603         const struct regulator_ops *ops = rdev->desc->ops;
2604
2605         if (ops->set_voltage_sel != regulator_set_voltage_sel_regmap)
2606                 return -EOPNOTSUPP;
2607
2608          *vsel_reg = rdev->desc->vsel_reg;
2609          *vsel_mask = rdev->desc->vsel_mask;
2610
2611          return 0;
2612 }
2613 EXPORT_SYMBOL_GPL(regulator_get_hardware_vsel_register);
2614
2615 /**
2616  * regulator_list_hardware_vsel - get the HW-specific register value for a selector
2617  * @regulator: regulator source
2618  * @selector: identify voltage to list
2619  *
2620  * Converts the selector to a hardware-specific voltage selector that can be
2621  * directly written to the regulator registers. The address of the voltage
2622  * register can be determined by calling @regulator_get_hardware_vsel_register.
2623  *
2624  * On error a negative errno is returned.
2625  */
2626 int regulator_list_hardware_vsel(struct regulator *regulator,
2627                                  unsigned selector)
2628 {
2629         struct regulator_dev *rdev = regulator->rdev;
2630         const struct regulator_ops *ops = rdev->desc->ops;
2631
2632         if (selector >= rdev->desc->n_voltages)
2633                 return -EINVAL;
2634         if (ops->set_voltage_sel != regulator_set_voltage_sel_regmap)
2635                 return -EOPNOTSUPP;
2636
2637         return selector;
2638 }
2639 EXPORT_SYMBOL_GPL(regulator_list_hardware_vsel);
2640
2641 /**
2642  * regulator_get_linear_step - return the voltage step size between VSEL values
2643  * @regulator: regulator source
2644  *
2645  * Returns the voltage step size between VSEL values for linear
2646  * regulators, or return 0 if the regulator isn't a linear regulator.
2647  */
2648 unsigned int regulator_get_linear_step(struct regulator *regulator)
2649 {
2650         struct regulator_dev *rdev = regulator->rdev;
2651
2652         return rdev->desc->uV_step;
2653 }
2654 EXPORT_SYMBOL_GPL(regulator_get_linear_step);
2655
2656 /**
2657  * regulator_is_supported_voltage - check if a voltage range can be supported
2658  *
2659  * @regulator: Regulator to check.
2660  * @min_uV: Minimum required voltage in uV.
2661  * @max_uV: Maximum required voltage in uV.
2662  *
2663  * Returns a boolean or a negative error code.
2664  */
2665 int regulator_is_supported_voltage(struct regulator *regulator,
2666                                    int min_uV, int max_uV)
2667 {
2668         struct regulator_dev *rdev = regulator->rdev;
2669         int i, voltages, ret;
2670
2671         /* If we can't change voltage check the current voltage */
2672         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE)) {
2673                 ret = regulator_get_voltage(regulator);
2674                 if (ret >= 0)
2675                         return min_uV <= ret && ret <= max_uV;
2676                 else
2677                         return ret;
2678         }
2679
2680         /* Any voltage within constrains range is fine? */
2681         if (rdev->desc->continuous_voltage_range)
2682                 return min_uV >= rdev->constraints->min_uV &&
2683                                 max_uV <= rdev->constraints->max_uV;
2684
2685         ret = regulator_count_voltages(regulator);
2686         if (ret < 0)
2687                 return ret;
2688         voltages = ret;
2689
2690         for (i = 0; i < voltages; i++) {
2691                 ret = regulator_list_voltage(regulator, i);
2692
2693                 if (ret >= min_uV && ret <= max_uV)
2694                         return 1;
2695         }
2696
2697         return 0;
2698 }
2699 EXPORT_SYMBOL_GPL(regulator_is_supported_voltage);
2700
2701 static int regulator_map_voltage(struct regulator_dev *rdev, int min_uV,
2702                                  int max_uV)
2703 {
2704         const struct regulator_desc *desc = rdev->desc;
2705
2706         if (desc->ops->map_voltage)
2707                 return desc->ops->map_voltage(rdev, min_uV, max_uV);
2708
2709         if (desc->ops->list_voltage == regulator_list_voltage_linear)
2710                 return regulator_map_voltage_linear(rdev, min_uV, max_uV);
2711
2712         if (desc->ops->list_voltage == regulator_list_voltage_linear_range)
2713                 return regulator_map_voltage_linear_range(rdev, min_uV, max_uV);
2714
2715         return regulator_map_voltage_iterate(rdev, min_uV, max_uV);
2716 }
2717
2718 static int _regulator_call_set_voltage(struct regulator_dev *rdev,
2719                                        int min_uV, int max_uV,
2720                                        unsigned *selector)
2721 {
2722         struct pre_voltage_change_data data;
2723         int ret;
2724
2725         data.old_uV = _regulator_get_voltage(rdev);
2726         data.min_uV = min_uV;
2727         data.max_uV = max_uV;
2728         ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE,
2729                                    &data);
2730         if (ret & NOTIFY_STOP_MASK)
2731                 return -EINVAL;
2732
2733         ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV, selector);
2734         if (ret >= 0)
2735                 return ret;
2736
2737         _notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE,
2738                              (void *)data.old_uV);
2739
2740         return ret;
2741 }
2742
2743 static int _regulator_call_set_voltage_sel(struct regulator_dev *rdev,
2744                                            int uV, unsigned selector)
2745 {
2746         struct pre_voltage_change_data data;
2747         int ret;
2748
2749         data.old_uV = _regulator_get_voltage(rdev);
2750         data.min_uV = uV;
2751         data.max_uV = uV;
2752         ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE,
2753                                    &data);
2754         if (ret & NOTIFY_STOP_MASK)
2755                 return -EINVAL;
2756
2757         ret = rdev->desc->ops->set_voltage_sel(rdev, selector);
2758         if (ret >= 0)
2759                 return ret;
2760
2761         _notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE,
2762                              (void *)data.old_uV);
2763
2764         return ret;
2765 }
2766
2767 static int _regulator_set_voltage_time(struct regulator_dev *rdev,
2768                                        int old_uV, int new_uV)
2769 {
2770         unsigned int ramp_delay = 0;
2771
2772         if (rdev->constraints->ramp_delay)
2773                 ramp_delay = rdev->constraints->ramp_delay;
2774         else if (rdev->desc->ramp_delay)
2775                 ramp_delay = rdev->desc->ramp_delay;
2776         else if (rdev->constraints->settling_time)
2777                 return rdev->constraints->settling_time;
2778         else if (rdev->constraints->settling_time_up &&
2779                  (new_uV > old_uV))
2780                 return rdev->constraints->settling_time_up;
2781         else if (rdev->constraints->settling_time_down &&
2782                  (new_uV < old_uV))
2783                 return rdev->constraints->settling_time_down;
2784
2785         if (ramp_delay == 0) {
2786                 rdev_dbg(rdev, "ramp_delay not set\n");
2787                 return 0;
2788         }
2789
2790         return DIV_ROUND_UP(abs(new_uV - old_uV), ramp_delay);
2791 }
2792
2793 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
2794                                      int min_uV, int max_uV)
2795 {
2796         int ret;
2797         int delay = 0;
2798         int best_val = 0;
2799         unsigned int selector;
2800         int old_selector = -1;
2801         const struct regulator_ops *ops = rdev->desc->ops;
2802         int old_uV = _regulator_get_voltage(rdev);
2803
2804         trace_regulator_set_voltage(rdev_get_name(rdev), min_uV, max_uV);
2805
2806         min_uV += rdev->constraints->uV_offset;
2807         max_uV += rdev->constraints->uV_offset;
2808
2809         /*
2810          * If we can't obtain the old selector there is not enough
2811          * info to call set_voltage_time_sel().
2812          */
2813         if (_regulator_is_enabled(rdev) &&
2814             ops->set_voltage_time_sel && ops->get_voltage_sel) {
2815                 old_selector = ops->get_voltage_sel(rdev);
2816                 if (old_selector < 0)
2817                         return old_selector;
2818         }
2819
2820         if (ops->set_voltage) {
2821                 ret = _regulator_call_set_voltage(rdev, min_uV, max_uV,
2822                                                   &selector);
2823
2824                 if (ret >= 0) {
2825                         if (ops->list_voltage)
2826                                 best_val = ops->list_voltage(rdev,
2827                                                              selector);
2828                         else
2829                                 best_val = _regulator_get_voltage(rdev);
2830                 }
2831
2832         } else if (ops->set_voltage_sel) {
2833                 ret = regulator_map_voltage(rdev, min_uV, max_uV);
2834                 if (ret >= 0) {
2835                         best_val = ops->list_voltage(rdev, ret);
2836                         if (min_uV <= best_val && max_uV >= best_val) {
2837                                 selector = ret;
2838                                 if (old_selector == selector)
2839                                         ret = 0;
2840                                 else
2841                                         ret = _regulator_call_set_voltage_sel(
2842                                                 rdev, best_val, selector);
2843                         } else {
2844                                 ret = -EINVAL;
2845                         }
2846                 }
2847         } else {
2848                 ret = -EINVAL;
2849         }
2850
2851         if (ret)
2852                 goto out;
2853
2854         if (ops->set_voltage_time_sel) {
2855                 /*
2856                  * Call set_voltage_time_sel if successfully obtained
2857                  * old_selector
2858                  */
2859                 if (old_selector >= 0 && old_selector != selector)
2860                         delay = ops->set_voltage_time_sel(rdev, old_selector,
2861                                                           selector);
2862         } else {
2863                 if (old_uV != best_val) {
2864                         if (ops->set_voltage_time)
2865                                 delay = ops->set_voltage_time(rdev, old_uV,
2866                                                               best_val);
2867                         else
2868                                 delay = _regulator_set_voltage_time(rdev,
2869                                                                     old_uV,
2870                                                                     best_val);
2871                 }
2872         }
2873
2874         if (delay < 0) {
2875                 rdev_warn(rdev, "failed to get delay: %d\n", delay);
2876                 delay = 0;
2877         }
2878
2879         /* Insert any necessary delays */
2880         if (delay >= 1000) {
2881                 mdelay(delay / 1000);
2882                 udelay(delay % 1000);
2883         } else if (delay) {
2884                 udelay(delay);
2885         }
2886
2887         if (best_val >= 0) {
2888                 unsigned long data = best_val;
2889
2890                 _notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE,
2891                                      (void *)data);
2892         }
2893
2894 out:
2895         trace_regulator_set_voltage_complete(rdev_get_name(rdev), best_val);
2896
2897         return ret;
2898 }
2899
2900 static int regulator_set_voltage_unlocked(struct regulator *regulator,
2901                                           int min_uV, int max_uV)
2902 {
2903         struct regulator_dev *rdev = regulator->rdev;
2904         int ret = 0;
2905         int old_min_uV, old_max_uV;
2906         int current_uV;
2907         int best_supply_uV = 0;
2908         int supply_change_uV = 0;
2909
2910         /* If we're setting the same range as last time the change
2911          * should be a noop (some cpufreq implementations use the same
2912          * voltage for multiple frequencies, for example).
2913          */
2914         if (regulator->min_uV == min_uV && regulator->max_uV == max_uV)
2915                 goto out;
2916
2917         /* If we're trying to set a range that overlaps the current voltage,
2918          * return successfully even though the regulator does not support
2919          * changing the voltage.
2920          */
2921         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE)) {
2922                 current_uV = _regulator_get_voltage(rdev);
2923                 if (min_uV <= current_uV && current_uV <= max_uV) {
2924                         regulator->min_uV = min_uV;
2925                         regulator->max_uV = max_uV;
2926                         goto out;
2927                 }
2928         }
2929
2930         /* sanity check */
2931         if (!rdev->desc->ops->set_voltage &&
2932             !rdev->desc->ops->set_voltage_sel) {
2933                 ret = -EINVAL;
2934                 goto out;
2935         }
2936
2937         /* constraints check */
2938         ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
2939         if (ret < 0)
2940                 goto out;
2941
2942         /* restore original values in case of error */
2943         old_min_uV = regulator->min_uV;
2944         old_max_uV = regulator->max_uV;
2945         regulator->min_uV = min_uV;
2946         regulator->max_uV = max_uV;
2947
2948         ret = regulator_check_consumers(rdev, &min_uV, &max_uV);
2949         if (ret < 0)
2950                 goto out2;
2951
2952         if (rdev->supply &&
2953             regulator_ops_is_valid(rdev->supply->rdev,
2954                                    REGULATOR_CHANGE_VOLTAGE) &&
2955             (rdev->desc->min_dropout_uV || !(rdev->desc->ops->get_voltage ||
2956                                            rdev->desc->ops->get_voltage_sel))) {
2957                 int current_supply_uV;
2958                 int selector;
2959
2960                 selector = regulator_map_voltage(rdev, min_uV, max_uV);
2961                 if (selector < 0) {
2962                         ret = selector;
2963                         goto out2;
2964                 }
2965
2966                 best_supply_uV = _regulator_list_voltage(regulator, selector, 0);
2967                 if (best_supply_uV < 0) {
2968                         ret = best_supply_uV;
2969                         goto out2;
2970                 }
2971
2972                 best_supply_uV += rdev->desc->min_dropout_uV;
2973
2974                 current_supply_uV = _regulator_get_voltage(rdev->supply->rdev);
2975                 if (current_supply_uV < 0) {
2976                         ret = current_supply_uV;
2977                         goto out2;
2978                 }
2979
2980                 supply_change_uV = best_supply_uV - current_supply_uV;
2981         }
2982
2983         if (supply_change_uV > 0) {
2984                 ret = regulator_set_voltage_unlocked(rdev->supply,
2985                                 best_supply_uV, INT_MAX);
2986                 if (ret) {
2987                         dev_err(&rdev->dev, "Failed to increase supply voltage: %d\n",
2988                                         ret);
2989                         goto out2;
2990                 }
2991         }
2992
2993         ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
2994         if (ret < 0)
2995                 goto out2;
2996
2997         if (supply_change_uV < 0) {
2998                 ret = regulator_set_voltage_unlocked(rdev->supply,
2999                                 best_supply_uV, INT_MAX);
3000                 if (ret)
3001                         dev_warn(&rdev->dev, "Failed to decrease supply voltage: %d\n",
3002                                         ret);
3003                 /* No need to fail here */
3004                 ret = 0;
3005         }
3006
3007 out:
3008         return ret;
3009 out2:
3010         regulator->min_uV = old_min_uV;
3011         regulator->max_uV = old_max_uV;
3012
3013         return ret;
3014 }
3015
3016 /**
3017  * regulator_set_voltage - set regulator output voltage
3018  * @regulator: regulator source
3019  * @min_uV: Minimum required voltage in uV
3020  * @max_uV: Maximum acceptable voltage in uV
3021  *
3022  * Sets a voltage regulator to the desired output voltage. This can be set
3023  * during any regulator state. IOW, regulator can be disabled or enabled.
3024  *
3025  * If the regulator is enabled then the voltage will change to the new value
3026  * immediately otherwise if the regulator is disabled the regulator will
3027  * output at the new voltage when enabled.
3028  *
3029  * NOTE: If the regulator is shared between several devices then the lowest
3030  * request voltage that meets the system constraints will be used.
3031  * Regulator system constraints must be set for this regulator before
3032  * calling this function otherwise this call will fail.
3033  */
3034 int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
3035 {
3036         int ret = 0;
3037
3038         regulator_lock_supply(regulator->rdev);
3039
3040         ret = regulator_set_voltage_unlocked(regulator, min_uV, max_uV);
3041
3042         regulator_unlock_supply(regulator->rdev);
3043
3044         return ret;
3045 }
3046 EXPORT_SYMBOL_GPL(regulator_set_voltage);
3047
3048 /**
3049  * regulator_set_voltage_time - get raise/fall time
3050  * @regulator: regulator source
3051  * @old_uV: starting voltage in microvolts
3052  * @new_uV: target voltage in microvolts
3053  *
3054  * Provided with the starting and ending voltage, this function attempts to
3055  * calculate the time in microseconds required to rise or fall to this new
3056  * voltage.
3057  */
3058 int regulator_set_voltage_time(struct regulator *regulator,
3059                                int old_uV, int new_uV)
3060 {
3061         struct regulator_dev *rdev = regulator->rdev;
3062         const struct regulator_ops *ops = rdev->desc->ops;
3063         int old_sel = -1;
3064         int new_sel = -1;
3065         int voltage;
3066         int i;
3067
3068         if (ops->set_voltage_time)
3069                 return ops->set_voltage_time(rdev, old_uV, new_uV);
3070         else if (!ops->set_voltage_time_sel)
3071                 return _regulator_set_voltage_time(rdev, old_uV, new_uV);
3072
3073         /* Currently requires operations to do this */
3074         if (!ops->list_voltage || !rdev->desc->n_voltages)
3075                 return -EINVAL;
3076
3077         for (i = 0; i < rdev->desc->n_voltages; i++) {
3078                 /* We only look for exact voltage matches here */
3079                 voltage = regulator_list_voltage(regulator, i);
3080                 if (voltage < 0)
3081                         return -EINVAL;
3082                 if (voltage == 0)
3083                         continue;
3084                 if (voltage == old_uV)
3085                         old_sel = i;
3086                 if (voltage == new_uV)
3087                         new_sel = i;
3088         }
3089
3090         if (old_sel < 0 || new_sel < 0)
3091                 return -EINVAL;
3092
3093         return ops->set_voltage_time_sel(rdev, old_sel, new_sel);
3094 }
3095 EXPORT_SYMBOL_GPL(regulator_set_voltage_time);
3096
3097 /**
3098  * regulator_set_voltage_time_sel - get raise/fall time
3099  * @rdev: regulator source device
3100  * @old_selector: selector for starting voltage
3101  * @new_selector: selector for target voltage
3102  *
3103  * Provided with the starting and target voltage selectors, this function
3104  * returns time in microseconds required to rise or fall to this new voltage
3105  *
3106  * Drivers providing ramp_delay in regulation_constraints can use this as their
3107  * set_voltage_time_sel() operation.
3108  */
3109 int regulator_set_voltage_time_sel(struct regulator_dev *rdev,
3110                                    unsigned int old_selector,
3111                                    unsigned int new_selector)
3112 {
3113         int old_volt, new_volt;
3114
3115         /* sanity check */
3116         if (!rdev->desc->ops->list_voltage)
3117                 return -EINVAL;
3118
3119         old_volt = rdev->desc->ops->list_voltage(rdev, old_selector);
3120         new_volt = rdev->desc->ops->list_voltage(rdev, new_selector);
3121
3122         if (rdev->desc->ops->set_voltage_time)
3123                 return rdev->desc->ops->set_voltage_time(rdev, old_volt,
3124                                                          new_volt);
3125         else
3126                 return _regulator_set_voltage_time(rdev, old_volt, new_volt);
3127 }
3128 EXPORT_SYMBOL_GPL(regulator_set_voltage_time_sel);
3129
3130 /**
3131  * regulator_sync_voltage - re-apply last regulator output voltage
3132  * @regulator: regulator source
3133  *
3134  * Re-apply the last configured voltage.  This is intended to be used
3135  * where some external control source the consumer is cooperating with
3136  * has caused the configured voltage to change.
3137  */
3138 int regulator_sync_voltage(struct regulator *regulator)
3139 {
3140         struct regulator_dev *rdev = regulator->rdev;
3141         int ret, min_uV, max_uV;
3142
3143         mutex_lock(&rdev->mutex);
3144
3145         if (!rdev->desc->ops->set_voltage &&
3146             !rdev->desc->ops->set_voltage_sel) {
3147                 ret = -EINVAL;
3148                 goto out;
3149         }
3150
3151         /* This is only going to work if we've had a voltage configured. */
3152         if (!regulator->min_uV && !regulator->max_uV) {
3153                 ret = -EINVAL;
3154                 goto out;
3155         }
3156
3157         min_uV = regulator->min_uV;
3158         max_uV = regulator->max_uV;
3159
3160         /* This should be a paranoia check... */
3161         ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
3162         if (ret < 0)
3163                 goto out;
3164
3165         ret = regulator_check_consumers(rdev, &min_uV, &max_uV);
3166         if (ret < 0)
3167                 goto out;
3168
3169         ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
3170
3171 out:
3172         mutex_unlock(&rdev->mutex);
3173         return ret;
3174 }
3175 EXPORT_SYMBOL_GPL(regulator_sync_voltage);
3176
3177 static int _regulator_get_voltage(struct regulator_dev *rdev)
3178 {
3179         int sel, ret;
3180         bool bypassed;
3181
3182         if (rdev->desc->ops->get_bypass) {
3183                 ret = rdev->desc->ops->get_bypass(rdev, &bypassed);
3184                 if (ret < 0)
3185                         return ret;
3186                 if (bypassed) {
3187                         /* if bypassed the regulator must have a supply */
3188                         if (!rdev->supply) {
3189                                 rdev_err(rdev,
3190                                          "bypassed regulator has no supply!\n");
3191                                 return -EPROBE_DEFER;
3192                         }
3193
3194                         return _regulator_get_voltage(rdev->supply->rdev);
3195                 }
3196         }
3197
3198         if (rdev->desc->ops->get_voltage_sel) {
3199                 sel = rdev->desc->ops->get_voltage_sel(rdev);
3200                 if (sel < 0)
3201                         return sel;
3202                 ret = rdev->desc->ops->list_voltage(rdev, sel);
3203         } else if (rdev->desc->ops->get_voltage) {
3204                 ret = rdev->desc->ops->get_voltage(rdev);
3205         } else if (rdev->desc->ops->list_voltage) {
3206                 ret = rdev->desc->ops->list_voltage(rdev, 0);
3207         } else if (rdev->desc->fixed_uV && (rdev->desc->n_voltages == 1)) {
3208                 ret = rdev->desc->fixed_uV;
3209         } else if (rdev->supply) {
3210                 ret = _regulator_get_voltage(rdev->supply->rdev);
3211         } else {
3212                 return -EINVAL;
3213         }
3214
3215         if (ret < 0)
3216                 return ret;
3217         return ret - rdev->constraints->uV_offset;
3218 }
3219
3220 /**
3221  * regulator_get_voltage - get regulator output voltage
3222  * @regulator: regulator source
3223  *
3224  * This returns the current regulator voltage in uV.
3225  *
3226  * NOTE: If the regulator is disabled it will return the voltage value. This
3227  * function should not be used to determine regulator state.
3228  */
3229 int regulator_get_voltage(struct regulator *regulator)
3230 {
3231         int ret;
3232
3233         regulator_lock_supply(regulator->rdev);
3234
3235         ret = _regulator_get_voltage(regulator->rdev);
3236
3237         regulator_unlock_supply(regulator->rdev);
3238
3239   &nb