78387a6cbae59e40a6fb05fc255647cacfe3209b
[linux-drm-fsl-dcu.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_list);
55 static LIST_HEAD(regulator_map_list);
56 static LIST_HEAD(regulator_ena_gpio_list);
57 static LIST_HEAD(regulator_supply_alias_list);
58 static bool has_full_constraints;
59
60 static struct dentry *debugfs_root;
61
62 /*
63  * struct regulator_map
64  *
65  * Used to provide symbolic supply names to devices.
66  */
67 struct regulator_map {
68         struct list_head list;
69         const char *dev_name;   /* The dev_name() for the consumer */
70         const char *supply;
71         struct regulator_dev *regulator;
72 };
73
74 /*
75  * struct regulator_enable_gpio
76  *
77  * Management for shared enable GPIO pin
78  */
79 struct regulator_enable_gpio {
80         struct list_head list;
81         struct gpio_desc *gpiod;
82         u32 enable_count;       /* a number of enabled shared GPIO */
83         u32 request_count;      /* a number of requested shared GPIO */
84         unsigned int ena_gpio_invert:1;
85 };
86
87 /*
88  * struct regulator_supply_alias
89  *
90  * Used to map lookups for a supply onto an alternative device.
91  */
92 struct regulator_supply_alias {
93         struct list_head list;
94         struct device *src_dev;
95         const char *src_supply;
96         struct device *alias_dev;
97         const char *alias_supply;
98 };
99
100 static int _regulator_is_enabled(struct regulator_dev *rdev);
101 static int _regulator_disable(struct regulator_dev *rdev);
102 static int _regulator_get_voltage(struct regulator_dev *rdev);
103 static int _regulator_get_current_limit(struct regulator_dev *rdev);
104 static unsigned int _regulator_get_mode(struct regulator_dev *rdev);
105 static int _notifier_call_chain(struct regulator_dev *rdev,
106                                   unsigned long event, void *data);
107 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
108                                      int min_uV, int max_uV);
109 static struct regulator *create_regulator(struct regulator_dev *rdev,
110                                           struct device *dev,
111                                           const char *supply_name);
112 static void _regulator_put(struct regulator *regulator);
113
114 static const char *rdev_get_name(struct regulator_dev *rdev)
115 {
116         if (rdev->constraints && rdev->constraints->name)
117                 return rdev->constraints->name;
118         else if (rdev->desc->name)
119                 return rdev->desc->name;
120         else
121                 return "";
122 }
123
124 static bool have_full_constraints(void)
125 {
126         return has_full_constraints || of_have_populated_dt();
127 }
128
129 /**
130  * of_get_regulator - get a regulator device node based on supply name
131  * @dev: Device pointer for the consumer (of regulator) device
132  * @supply: regulator supply name
133  *
134  * Extract the regulator device node corresponding to the supply name.
135  * returns the device node corresponding to the regulator if found, else
136  * returns NULL.
137  */
138 static struct device_node *of_get_regulator(struct device *dev, const char *supply)
139 {
140         struct device_node *regnode = NULL;
141         char prop_name[32]; /* 32 is max size of property name */
142
143         dev_dbg(dev, "Looking up %s-supply from device tree\n", supply);
144
145         snprintf(prop_name, 32, "%s-supply", supply);
146         regnode = of_parse_phandle(dev->of_node, prop_name, 0);
147
148         if (!regnode) {
149                 dev_dbg(dev, "Looking up %s property in node %s failed",
150                                 prop_name, dev->of_node->full_name);
151                 return NULL;
152         }
153         return regnode;
154 }
155
156 static int _regulator_can_change_status(struct regulator_dev *rdev)
157 {
158         if (!rdev->constraints)
159                 return 0;
160
161         if (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_STATUS)
162                 return 1;
163         else
164                 return 0;
165 }
166
167 /* Platform voltage constraint check */
168 static int regulator_check_voltage(struct regulator_dev *rdev,
169                                    int *min_uV, int *max_uV)
170 {
171         BUG_ON(*min_uV > *max_uV);
172
173         if (!rdev->constraints) {
174                 rdev_err(rdev, "no constraints\n");
175                 return -ENODEV;
176         }
177         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
178                 rdev_err(rdev, "operation not allowed\n");
179                 return -EPERM;
180         }
181
182         if (*max_uV > rdev->constraints->max_uV)
183                 *max_uV = rdev->constraints->max_uV;
184         if (*min_uV < rdev->constraints->min_uV)
185                 *min_uV = rdev->constraints->min_uV;
186
187         if (*min_uV > *max_uV) {
188                 rdev_err(rdev, "unsupportable voltage range: %d-%duV\n",
189                          *min_uV, *max_uV);
190                 return -EINVAL;
191         }
192
193         return 0;
194 }
195
196 /* Make sure we select a voltage that suits the needs of all
197  * regulator consumers
198  */
199 static int regulator_check_consumers(struct regulator_dev *rdev,
200                                      int *min_uV, int *max_uV)
201 {
202         struct regulator *regulator;
203
204         list_for_each_entry(regulator, &rdev->consumer_list, list) {
205                 /*
206                  * Assume consumers that didn't say anything are OK
207                  * with anything in the constraint range.
208                  */
209                 if (!regulator->min_uV && !regulator->max_uV)
210                         continue;
211
212                 if (*max_uV > regulator->max_uV)
213                         *max_uV = regulator->max_uV;
214                 if (*min_uV < regulator->min_uV)
215                         *min_uV = regulator->min_uV;
216         }
217
218         if (*min_uV > *max_uV) {
219                 rdev_err(rdev, "Restricting voltage, %u-%uuV\n",
220                         *min_uV, *max_uV);
221                 return -EINVAL;
222         }
223
224         return 0;
225 }
226
227 /* current constraint check */
228 static int regulator_check_current_limit(struct regulator_dev *rdev,
229                                         int *min_uA, int *max_uA)
230 {
231         BUG_ON(*min_uA > *max_uA);
232
233         if (!rdev->constraints) {
234                 rdev_err(rdev, "no constraints\n");
235                 return -ENODEV;
236         }
237         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_CURRENT)) {
238                 rdev_err(rdev, "operation not allowed\n");
239                 return -EPERM;
240         }
241
242         if (*max_uA > rdev->constraints->max_uA)
243                 *max_uA = rdev->constraints->max_uA;
244         if (*min_uA < rdev->constraints->min_uA)
245                 *min_uA = rdev->constraints->min_uA;
246
247         if (*min_uA > *max_uA) {
248                 rdev_err(rdev, "unsupportable current range: %d-%duA\n",
249                          *min_uA, *max_uA);
250                 return -EINVAL;
251         }
252
253         return 0;
254 }
255
256 /* operating mode constraint check */
257 static int regulator_mode_constrain(struct regulator_dev *rdev, int *mode)
258 {
259         switch (*mode) {
260         case REGULATOR_MODE_FAST:
261         case REGULATOR_MODE_NORMAL:
262         case REGULATOR_MODE_IDLE:
263         case REGULATOR_MODE_STANDBY:
264                 break;
265         default:
266                 rdev_err(rdev, "invalid mode %x specified\n", *mode);
267                 return -EINVAL;
268         }
269
270         if (!rdev->constraints) {
271                 rdev_err(rdev, "no constraints\n");
272                 return -ENODEV;
273         }
274         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_MODE)) {
275                 rdev_err(rdev, "operation not allowed\n");
276                 return -EPERM;
277         }
278
279         /* The modes are bitmasks, the most power hungry modes having
280          * the lowest values. If the requested mode isn't supported
281          * try higher modes. */
282         while (*mode) {
283                 if (rdev->constraints->valid_modes_mask & *mode)
284                         return 0;
285                 *mode /= 2;
286         }
287
288         return -EINVAL;
289 }
290
291 /* dynamic regulator mode switching constraint check */
292 static int regulator_check_drms(struct regulator_dev *rdev)
293 {
294         if (!rdev->constraints) {
295                 rdev_err(rdev, "no constraints\n");
296                 return -ENODEV;
297         }
298         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS)) {
299                 rdev_err(rdev, "operation not allowed\n");
300                 return -EPERM;
301         }
302         return 0;
303 }
304
305 static ssize_t regulator_uV_show(struct device *dev,
306                                 struct device_attribute *attr, char *buf)
307 {
308         struct regulator_dev *rdev = dev_get_drvdata(dev);
309         ssize_t ret;
310
311         mutex_lock(&rdev->mutex);
312         ret = sprintf(buf, "%d\n", _regulator_get_voltage(rdev));
313         mutex_unlock(&rdev->mutex);
314
315         return ret;
316 }
317 static DEVICE_ATTR(microvolts, 0444, regulator_uV_show, NULL);
318
319 static ssize_t regulator_uA_show(struct device *dev,
320                                 struct device_attribute *attr, char *buf)
321 {
322         struct regulator_dev *rdev = dev_get_drvdata(dev);
323
324         return sprintf(buf, "%d\n", _regulator_get_current_limit(rdev));
325 }
326 static DEVICE_ATTR(microamps, 0444, regulator_uA_show, NULL);
327
328 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
329                          char *buf)
330 {
331         struct regulator_dev *rdev = dev_get_drvdata(dev);
332
333         return sprintf(buf, "%s\n", rdev_get_name(rdev));
334 }
335 static DEVICE_ATTR_RO(name);
336
337 static ssize_t regulator_print_opmode(char *buf, int mode)
338 {
339         switch (mode) {
340         case REGULATOR_MODE_FAST:
341                 return sprintf(buf, "fast\n");
342         case REGULATOR_MODE_NORMAL:
343                 return sprintf(buf, "normal\n");
344         case REGULATOR_MODE_IDLE:
345                 return sprintf(buf, "idle\n");
346         case REGULATOR_MODE_STANDBY:
347                 return sprintf(buf, "standby\n");
348         }
349         return sprintf(buf, "unknown\n");
350 }
351
352 static ssize_t regulator_opmode_show(struct device *dev,
353                                     struct device_attribute *attr, char *buf)
354 {
355         struct regulator_dev *rdev = dev_get_drvdata(dev);
356
357         return regulator_print_opmode(buf, _regulator_get_mode(rdev));
358 }
359 static DEVICE_ATTR(opmode, 0444, regulator_opmode_show, NULL);
360
361 static ssize_t regulator_print_state(char *buf, int state)
362 {
363         if (state > 0)
364                 return sprintf(buf, "enabled\n");
365         else if (state == 0)
366                 return sprintf(buf, "disabled\n");
367         else
368                 return sprintf(buf, "unknown\n");
369 }
370
371 static ssize_t regulator_state_show(struct device *dev,
372                                    struct device_attribute *attr, char *buf)
373 {
374         struct regulator_dev *rdev = dev_get_drvdata(dev);
375         ssize_t ret;
376
377         mutex_lock(&rdev->mutex);
378         ret = regulator_print_state(buf, _regulator_is_enabled(rdev));
379         mutex_unlock(&rdev->mutex);
380
381         return ret;
382 }
383 static DEVICE_ATTR(state, 0444, regulator_state_show, NULL);
384
385 static ssize_t regulator_status_show(struct device *dev,
386                                    struct device_attribute *attr, char *buf)
387 {
388         struct regulator_dev *rdev = dev_get_drvdata(dev);
389         int status;
390         char *label;
391
392         status = rdev->desc->ops->get_status(rdev);
393         if (status < 0)
394                 return status;
395
396         switch (status) {
397         case REGULATOR_STATUS_OFF:
398                 label = "off";
399                 break;
400         case REGULATOR_STATUS_ON:
401                 label = "on";
402                 break;
403         case REGULATOR_STATUS_ERROR:
404                 label = "error";
405                 break;
406         case REGULATOR_STATUS_FAST:
407                 label = "fast";
408                 break;
409         case REGULATOR_STATUS_NORMAL:
410                 label = "normal";
411                 break;
412         case REGULATOR_STATUS_IDLE:
413                 label = "idle";
414                 break;
415         case REGULATOR_STATUS_STANDBY:
416                 label = "standby";
417                 break;
418         case REGULATOR_STATUS_BYPASS:
419                 label = "bypass";
420                 break;
421         case REGULATOR_STATUS_UNDEFINED:
422                 label = "undefined";
423                 break;
424         default:
425                 return -ERANGE;
426         }
427
428         return sprintf(buf, "%s\n", label);
429 }
430 static DEVICE_ATTR(status, 0444, regulator_status_show, NULL);
431
432 static ssize_t regulator_min_uA_show(struct device *dev,
433                                     struct device_attribute *attr, char *buf)
434 {
435         struct regulator_dev *rdev = dev_get_drvdata(dev);
436
437         if (!rdev->constraints)
438                 return sprintf(buf, "constraint not defined\n");
439
440         return sprintf(buf, "%d\n", rdev->constraints->min_uA);
441 }
442 static DEVICE_ATTR(min_microamps, 0444, regulator_min_uA_show, NULL);
443
444 static ssize_t regulator_max_uA_show(struct device *dev,
445                                     struct device_attribute *attr, char *buf)
446 {
447         struct regulator_dev *rdev = dev_get_drvdata(dev);
448
449         if (!rdev->constraints)
450                 return sprintf(buf, "constraint not defined\n");
451
452         return sprintf(buf, "%d\n", rdev->constraints->max_uA);
453 }
454 static DEVICE_ATTR(max_microamps, 0444, regulator_max_uA_show, NULL);
455
456 static ssize_t regulator_min_uV_show(struct device *dev,
457                                     struct device_attribute *attr, char *buf)
458 {
459         struct regulator_dev *rdev = dev_get_drvdata(dev);
460
461         if (!rdev->constraints)
462                 return sprintf(buf, "constraint not defined\n");
463
464         return sprintf(buf, "%d\n", rdev->constraints->min_uV);
465 }
466 static DEVICE_ATTR(min_microvolts, 0444, regulator_min_uV_show, NULL);
467
468 static ssize_t regulator_max_uV_show(struct device *dev,
469                                     struct device_attribute *attr, char *buf)
470 {
471         struct regulator_dev *rdev = dev_get_drvdata(dev);
472
473         if (!rdev->constraints)
474                 return sprintf(buf, "constraint not defined\n");
475
476         return sprintf(buf, "%d\n", rdev->constraints->max_uV);
477 }
478 static DEVICE_ATTR(max_microvolts, 0444, regulator_max_uV_show, NULL);
479
480 static ssize_t regulator_total_uA_show(struct device *dev,
481                                       struct device_attribute *attr, char *buf)
482 {
483         struct regulator_dev *rdev = dev_get_drvdata(dev);
484         struct regulator *regulator;
485         int uA = 0;
486
487         mutex_lock(&rdev->mutex);
488         list_for_each_entry(regulator, &rdev->consumer_list, list)
489                 uA += regulator->uA_load;
490         mutex_unlock(&rdev->mutex);
491         return sprintf(buf, "%d\n", uA);
492 }
493 static DEVICE_ATTR(requested_microamps, 0444, regulator_total_uA_show, NULL);
494
495 static ssize_t num_users_show(struct device *dev, struct device_attribute *attr,
496                               char *buf)
497 {
498         struct regulator_dev *rdev = dev_get_drvdata(dev);
499         return sprintf(buf, "%d\n", rdev->use_count);
500 }
501 static DEVICE_ATTR_RO(num_users);
502
503 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
504                          char *buf)
505 {
506         struct regulator_dev *rdev = dev_get_drvdata(dev);
507
508         switch (rdev->desc->type) {
509         case REGULATOR_VOLTAGE:
510                 return sprintf(buf, "voltage\n");
511         case REGULATOR_CURRENT:
512                 return sprintf(buf, "current\n");
513         }
514         return sprintf(buf, "unknown\n");
515 }
516 static DEVICE_ATTR_RO(type);
517
518 static ssize_t regulator_suspend_mem_uV_show(struct device *dev,
519                                 struct device_attribute *attr, char *buf)
520 {
521         struct regulator_dev *rdev = dev_get_drvdata(dev);
522
523         return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
524 }
525 static DEVICE_ATTR(suspend_mem_microvolts, 0444,
526                 regulator_suspend_mem_uV_show, NULL);
527
528 static ssize_t regulator_suspend_disk_uV_show(struct device *dev,
529                                 struct device_attribute *attr, char *buf)
530 {
531         struct regulator_dev *rdev = dev_get_drvdata(dev);
532
533         return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
534 }
535 static DEVICE_ATTR(suspend_disk_microvolts, 0444,
536                 regulator_suspend_disk_uV_show, NULL);
537
538 static ssize_t regulator_suspend_standby_uV_show(struct device *dev,
539                                 struct device_attribute *attr, char *buf)
540 {
541         struct regulator_dev *rdev = dev_get_drvdata(dev);
542
543         return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
544 }
545 static DEVICE_ATTR(suspend_standby_microvolts, 0444,
546                 regulator_suspend_standby_uV_show, NULL);
547
548 static ssize_t regulator_suspend_mem_mode_show(struct device *dev,
549                                 struct device_attribute *attr, char *buf)
550 {
551         struct regulator_dev *rdev = dev_get_drvdata(dev);
552
553         return regulator_print_opmode(buf,
554                 rdev->constraints->state_mem.mode);
555 }
556 static DEVICE_ATTR(suspend_mem_mode, 0444,
557                 regulator_suspend_mem_mode_show, NULL);
558
559 static ssize_t regulator_suspend_disk_mode_show(struct device *dev,
560                                 struct device_attribute *attr, char *buf)
561 {
562         struct regulator_dev *rdev = dev_get_drvdata(dev);
563
564         return regulator_print_opmode(buf,
565                 rdev->constraints->state_disk.mode);
566 }
567 static DEVICE_ATTR(suspend_disk_mode, 0444,
568                 regulator_suspend_disk_mode_show, NULL);
569
570 static ssize_t regulator_suspend_standby_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_standby.mode);
577 }
578 static DEVICE_ATTR(suspend_standby_mode, 0444,
579                 regulator_suspend_standby_mode_show, NULL);
580
581 static ssize_t regulator_suspend_mem_state_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_state(buf,
587                         rdev->constraints->state_mem.enabled);
588 }
589 static DEVICE_ATTR(suspend_mem_state, 0444,
590                 regulator_suspend_mem_state_show, NULL);
591
592 static ssize_t regulator_suspend_disk_state_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_state(buf,
598                         rdev->constraints->state_disk.enabled);
599 }
600 static DEVICE_ATTR(suspend_disk_state, 0444,
601                 regulator_suspend_disk_state_show, NULL);
602
603 static ssize_t regulator_suspend_standby_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_standby.enabled);
610 }
611 static DEVICE_ATTR(suspend_standby_state, 0444,
612                 regulator_suspend_standby_state_show, NULL);
613
614 static ssize_t regulator_bypass_show(struct device *dev,
615                                      struct device_attribute *attr, char *buf)
616 {
617         struct regulator_dev *rdev = dev_get_drvdata(dev);
618         const char *report;
619         bool bypass;
620         int ret;
621
622         ret = rdev->desc->ops->get_bypass(rdev, &bypass);
623
624         if (ret != 0)
625                 report = "unknown";
626         else if (bypass)
627                 report = "enabled";
628         else
629                 report = "disabled";
630
631         return sprintf(buf, "%s\n", report);
632 }
633 static DEVICE_ATTR(bypass, 0444,
634                    regulator_bypass_show, NULL);
635
636 /* Calculate the new optimum regulator operating mode based on the new total
637  * consumer load. All locks held by caller */
638 static int drms_uA_update(struct regulator_dev *rdev)
639 {
640         struct regulator *sibling;
641         int current_uA = 0, output_uV, input_uV, err;
642         unsigned int mode;
643
644         /*
645          * first check to see if we can set modes at all, otherwise just
646          * tell the consumer everything is OK.
647          */
648         err = regulator_check_drms(rdev);
649         if (err < 0)
650                 return 0;
651
652         if (!rdev->desc->ops->get_optimum_mode &&
653             !rdev->desc->ops->set_load)
654                 return 0;
655
656         if (!rdev->desc->ops->set_mode &&
657             !rdev->desc->ops->set_load)
658                 return -EINVAL;
659
660         /* get output voltage */
661         output_uV = _regulator_get_voltage(rdev);
662         if (output_uV <= 0) {
663                 rdev_err(rdev, "invalid output voltage found\n");
664                 return -EINVAL;
665         }
666
667         /* get input voltage */
668         input_uV = 0;
669         if (rdev->supply)
670                 input_uV = regulator_get_voltage(rdev->supply);
671         if (input_uV <= 0)
672                 input_uV = rdev->constraints->input_uV;
673         if (input_uV <= 0) {
674                 rdev_err(rdev, "invalid input voltage found\n");
675                 return -EINVAL;
676         }
677
678         /* calc total requested load */
679         list_for_each_entry(sibling, &rdev->consumer_list, list)
680                 current_uA += sibling->uA_load;
681
682         current_uA += rdev->constraints->system_load;
683
684         if (rdev->desc->ops->set_load) {
685                 /* set the optimum mode for our new total regulator load */
686                 err = rdev->desc->ops->set_load(rdev, current_uA);
687                 if (err < 0)
688                         rdev_err(rdev, "failed to set load %d\n", current_uA);
689         } else {
690                 /* now get the optimum mode for our new total regulator load */
691                 mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
692                                                          output_uV, current_uA);
693
694                 /* check the new mode is allowed */
695                 err = regulator_mode_constrain(rdev, &mode);
696                 if (err < 0) {
697                         rdev_err(rdev, "failed to get optimum mode @ %d uA %d -> %d uV\n",
698                                  current_uA, input_uV, output_uV);
699                         return err;
700                 }
701
702                 err = rdev->desc->ops->set_mode(rdev, mode);
703                 if (err < 0)
704                         rdev_err(rdev, "failed to set optimum mode %x\n", mode);
705         }
706
707         return err;
708 }
709
710 static int suspend_set_state(struct regulator_dev *rdev,
711         struct regulator_state *rstate)
712 {
713         int ret = 0;
714
715         /* If we have no suspend mode configration don't set anything;
716          * only warn if the driver implements set_suspend_voltage or
717          * set_suspend_mode callback.
718          */
719         if (!rstate->enabled && !rstate->disabled) {
720                 if (rdev->desc->ops->set_suspend_voltage ||
721                     rdev->desc->ops->set_suspend_mode)
722                         rdev_warn(rdev, "No configuration\n");
723                 return 0;
724         }
725
726         if (rstate->enabled && rstate->disabled) {
727                 rdev_err(rdev, "invalid configuration\n");
728                 return -EINVAL;
729         }
730
731         if (rstate->enabled && rdev->desc->ops->set_suspend_enable)
732                 ret = rdev->desc->ops->set_suspend_enable(rdev);
733         else if (rstate->disabled && rdev->desc->ops->set_suspend_disable)
734                 ret = rdev->desc->ops->set_suspend_disable(rdev);
735         else /* OK if set_suspend_enable or set_suspend_disable is NULL */
736                 ret = 0;
737
738         if (ret < 0) {
739                 rdev_err(rdev, "failed to enabled/disable\n");
740                 return ret;
741         }
742
743         if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
744                 ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
745                 if (ret < 0) {
746                         rdev_err(rdev, "failed to set voltage\n");
747                         return ret;
748                 }
749         }
750
751         if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
752                 ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
753                 if (ret < 0) {
754                         rdev_err(rdev, "failed to set mode\n");
755                         return ret;
756                 }
757         }
758         return ret;
759 }
760
761 /* locks held by caller */
762 static int suspend_prepare(struct regulator_dev *rdev, suspend_state_t state)
763 {
764         if (!rdev->constraints)
765                 return -EINVAL;
766
767         switch (state) {
768         case PM_SUSPEND_STANDBY:
769                 return suspend_set_state(rdev,
770                         &rdev->constraints->state_standby);
771         case PM_SUSPEND_MEM:
772                 return suspend_set_state(rdev,
773                         &rdev->constraints->state_mem);
774         case PM_SUSPEND_MAX:
775                 return suspend_set_state(rdev,
776                         &rdev->constraints->state_disk);
777         default:
778                 return -EINVAL;
779         }
780 }
781
782 static void print_constraints(struct regulator_dev *rdev)
783 {
784         struct regulation_constraints *constraints = rdev->constraints;
785         char buf[160] = "";
786         size_t len = sizeof(buf) - 1;
787         int count = 0;
788         int ret;
789
790         if (constraints->min_uV && constraints->max_uV) {
791                 if (constraints->min_uV == constraints->max_uV)
792                         count += scnprintf(buf + count, len - count, "%d mV ",
793                                            constraints->min_uV / 1000);
794                 else
795                         count += scnprintf(buf + count, len - count,
796                                            "%d <--> %d mV ",
797                                            constraints->min_uV / 1000,
798                                            constraints->max_uV / 1000);
799         }
800
801         if (!constraints->min_uV ||
802             constraints->min_uV != constraints->max_uV) {
803                 ret = _regulator_get_voltage(rdev);
804                 if (ret > 0)
805                         count += scnprintf(buf + count, len - count,
806                                            "at %d mV ", ret / 1000);
807         }
808
809         if (constraints->uV_offset)
810                 count += scnprintf(buf + count, len - count, "%dmV offset ",
811                                    constraints->uV_offset / 1000);
812
813         if (constraints->min_uA && constraints->max_uA) {
814                 if (constraints->min_uA == constraints->max_uA)
815                         count += scnprintf(buf + count, len - count, "%d mA ",
816                                            constraints->min_uA / 1000);
817                 else
818                         count += scnprintf(buf + count, len - count,
819                                            "%d <--> %d mA ",
820                                            constraints->min_uA / 1000,
821                                            constraints->max_uA / 1000);
822         }
823
824         if (!constraints->min_uA ||
825             constraints->min_uA != constraints->max_uA) {
826                 ret = _regulator_get_current_limit(rdev);
827                 if (ret > 0)
828                         count += scnprintf(buf + count, len - count,
829                                            "at %d mA ", ret / 1000);
830         }
831
832         if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
833                 count += scnprintf(buf + count, len - count, "fast ");
834         if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
835                 count += scnprintf(buf + count, len - count, "normal ");
836         if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
837                 count += scnprintf(buf + count, len - count, "idle ");
838         if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
839                 count += scnprintf(buf + count, len - count, "standby");
840
841         if (!count)
842                 scnprintf(buf, len, "no parameters");
843
844         rdev_dbg(rdev, "%s\n", buf);
845
846         if ((constraints->min_uV != constraints->max_uV) &&
847             !(constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE))
848                 rdev_warn(rdev,
849                           "Voltage range but no REGULATOR_CHANGE_VOLTAGE\n");
850 }
851
852 static int machine_constraints_voltage(struct regulator_dev *rdev,
853         struct regulation_constraints *constraints)
854 {
855         const struct regulator_ops *ops = rdev->desc->ops;
856         int ret;
857
858         /* do we need to apply the constraint voltage */
859         if (rdev->constraints->apply_uV &&
860             rdev->constraints->min_uV == rdev->constraints->max_uV) {
861                 int current_uV = _regulator_get_voltage(rdev);
862                 if (current_uV < 0) {
863                         rdev_err(rdev,
864                                  "failed to get the current voltage(%d)\n",
865                                  current_uV);
866                         return current_uV;
867                 }
868                 if (current_uV < rdev->constraints->min_uV ||
869                     current_uV > rdev->constraints->max_uV) {
870                         ret = _regulator_do_set_voltage(
871                                 rdev, rdev->constraints->min_uV,
872                                 rdev->constraints->max_uV);
873                         if (ret < 0) {
874                                 rdev_err(rdev,
875                                         "failed to apply %duV constraint(%d)\n",
876                                         rdev->constraints->min_uV, ret);
877                                 return ret;
878                         }
879                 }
880         }
881
882         /* constrain machine-level voltage specs to fit
883          * the actual range supported by this regulator.
884          */
885         if (ops->list_voltage && rdev->desc->n_voltages) {
886                 int     count = rdev->desc->n_voltages;
887                 int     i;
888                 int     min_uV = INT_MAX;
889                 int     max_uV = INT_MIN;
890                 int     cmin = constraints->min_uV;
891                 int     cmax = constraints->max_uV;
892
893                 /* it's safe to autoconfigure fixed-voltage supplies
894                    and the constraints are used by list_voltage. */
895                 if (count == 1 && !cmin) {
896                         cmin = 1;
897                         cmax = INT_MAX;
898                         constraints->min_uV = cmin;
899                         constraints->max_uV = cmax;
900                 }
901
902                 /* voltage constraints are optional */
903                 if ((cmin == 0) && (cmax == 0))
904                         return 0;
905
906                 /* else require explicit machine-level constraints */
907                 if (cmin <= 0 || cmax <= 0 || cmax < cmin) {
908                         rdev_err(rdev, "invalid voltage constraints\n");
909                         return -EINVAL;
910                 }
911
912                 /* initial: [cmin..cmax] valid, [min_uV..max_uV] not */
913                 for (i = 0; i < count; i++) {
914                         int     value;
915
916                         value = ops->list_voltage(rdev, i);
917                         if (value <= 0)
918                                 continue;
919
920                         /* maybe adjust [min_uV..max_uV] */
921                         if (value >= cmin && value < min_uV)
922                                 min_uV = value;
923                         if (value <= cmax && value > max_uV)
924                                 max_uV = value;
925                 }
926
927                 /* final: [min_uV..max_uV] valid iff constraints valid */
928                 if (max_uV < min_uV) {
929                         rdev_err(rdev,
930                                  "unsupportable voltage constraints %u-%uuV\n",
931                                  min_uV, max_uV);
932                         return -EINVAL;
933                 }
934
935                 /* use regulator's subset of machine constraints */
936                 if (constraints->min_uV < min_uV) {
937                         rdev_dbg(rdev, "override min_uV, %d -> %d\n",
938                                  constraints->min_uV, min_uV);
939                         constraints->min_uV = min_uV;
940                 }
941                 if (constraints->max_uV > max_uV) {
942                         rdev_dbg(rdev, "override max_uV, %d -> %d\n",
943                                  constraints->max_uV, max_uV);
944                         constraints->max_uV = max_uV;
945                 }
946         }
947
948         return 0;
949 }
950
951 static int machine_constraints_current(struct regulator_dev *rdev,
952         struct regulation_constraints *constraints)
953 {
954         const struct regulator_ops *ops = rdev->desc->ops;
955         int ret;
956
957         if (!constraints->min_uA && !constraints->max_uA)
958                 return 0;
959
960         if (constraints->min_uA > constraints->max_uA) {
961                 rdev_err(rdev, "Invalid current constraints\n");
962                 return -EINVAL;
963         }
964
965         if (!ops->set_current_limit || !ops->get_current_limit) {
966                 rdev_warn(rdev, "Operation of current configuration missing\n");
967                 return 0;
968         }
969
970         /* Set regulator current in constraints range */
971         ret = ops->set_current_limit(rdev, constraints->min_uA,
972                         constraints->max_uA);
973         if (ret < 0) {
974                 rdev_err(rdev, "Failed to set current constraint, %d\n", ret);
975                 return ret;
976         }
977
978         return 0;
979 }
980
981 static int _regulator_do_enable(struct regulator_dev *rdev);
982
983 /**
984  * set_machine_constraints - sets regulator constraints
985  * @rdev: regulator source
986  * @constraints: constraints to apply
987  *
988  * Allows platform initialisation code to define and constrain
989  * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
990  * Constraints *must* be set by platform code in order for some
991  * regulator operations to proceed i.e. set_voltage, set_current_limit,
992  * set_mode.
993  */
994 static int set_machine_constraints(struct regulator_dev *rdev,
995         const struct regulation_constraints *constraints)
996 {
997         int ret = 0;
998         const struct regulator_ops *ops = rdev->desc->ops;
999
1000         if (constraints)
1001                 rdev->constraints = kmemdup(constraints, sizeof(*constraints),
1002                                             GFP_KERNEL);
1003         else
1004                 rdev->constraints = kzalloc(sizeof(*constraints),
1005                                             GFP_KERNEL);
1006         if (!rdev->constraints)
1007                 return -ENOMEM;
1008
1009         ret = machine_constraints_voltage(rdev, rdev->constraints);
1010         if (ret != 0)
1011                 goto out;
1012
1013         ret = machine_constraints_current(rdev, rdev->constraints);
1014         if (ret != 0)
1015                 goto out;
1016
1017         if (rdev->constraints->ilim_uA && ops->set_input_current_limit) {
1018                 ret = ops->set_input_current_limit(rdev,
1019                                                    rdev->constraints->ilim_uA);
1020                 if (ret < 0) {
1021                         rdev_err(rdev, "failed to set input limit\n");
1022                         goto out;
1023                 }
1024         }
1025
1026         /* do we need to setup our suspend state */
1027         if (rdev->constraints->initial_state) {
1028                 ret = suspend_prepare(rdev, rdev->constraints->initial_state);
1029                 if (ret < 0) {
1030                         rdev_err(rdev, "failed to set suspend state\n");
1031                         goto out;
1032                 }
1033         }
1034
1035         if (rdev->constraints->initial_mode) {
1036                 if (!ops->set_mode) {
1037                         rdev_err(rdev, "no set_mode operation\n");
1038                         ret = -EINVAL;
1039                         goto out;
1040                 }
1041
1042                 ret = ops->set_mode(rdev, rdev->constraints->initial_mode);
1043                 if (ret < 0) {
1044                         rdev_err(rdev, "failed to set initial mode: %d\n", ret);
1045                         goto out;
1046                 }
1047         }
1048
1049         /* If the constraints say the regulator should be on at this point
1050          * and we have control then make sure it is enabled.
1051          */
1052         if (rdev->constraints->always_on || rdev->constraints->boot_on) {
1053                 ret = _regulator_do_enable(rdev);
1054                 if (ret < 0 && ret != -EINVAL) {
1055                         rdev_err(rdev, "failed to enable\n");
1056                         goto out;
1057                 }
1058         }
1059
1060         if ((rdev->constraints->ramp_delay || rdev->constraints->ramp_disable)
1061                 && ops->set_ramp_delay) {
1062                 ret = ops->set_ramp_delay(rdev, rdev->constraints->ramp_delay);
1063                 if (ret < 0) {
1064                         rdev_err(rdev, "failed to set ramp_delay\n");
1065                         goto out;
1066                 }
1067         }
1068
1069         if (rdev->constraints->pull_down && ops->set_pull_down) {
1070                 ret = ops->set_pull_down(rdev);
1071                 if (ret < 0) {
1072                         rdev_err(rdev, "failed to set pull down\n");
1073                         goto out;
1074                 }
1075         }
1076
1077         if (rdev->constraints->soft_start && ops->set_soft_start) {
1078                 ret = ops->set_soft_start(rdev);
1079                 if (ret < 0) {
1080                         rdev_err(rdev, "failed to set soft start\n");
1081                         goto out;
1082                 }
1083         }
1084
1085         print_constraints(rdev);
1086         return 0;
1087 out:
1088         kfree(rdev->constraints);
1089         rdev->constraints = NULL;
1090         return ret;
1091 }
1092
1093 /**
1094  * set_supply - set regulator supply regulator
1095  * @rdev: regulator name
1096  * @supply_rdev: supply regulator name
1097  *
1098  * Called by platform initialisation code to set the supply regulator for this
1099  * regulator. This ensures that a regulators supply will also be enabled by the
1100  * core if it's child is enabled.
1101  */
1102 static int set_supply(struct regulator_dev *rdev,
1103                       struct regulator_dev *supply_rdev)
1104 {
1105         int err;
1106
1107         rdev_info(rdev, "supplied by %s\n", rdev_get_name(supply_rdev));
1108
1109         if (!try_module_get(supply_rdev->owner))
1110                 return -ENODEV;
1111
1112         rdev->supply = create_regulator(supply_rdev, &rdev->dev, "SUPPLY");
1113         if (rdev->supply == NULL) {
1114                 err = -ENOMEM;
1115                 return err;
1116         }
1117         supply_rdev->open_count++;
1118
1119         return 0;
1120 }
1121
1122 /**
1123  * set_consumer_device_supply - Bind a regulator to a symbolic supply
1124  * @rdev:         regulator source
1125  * @consumer_dev_name: dev_name() string for device supply applies to
1126  * @supply:       symbolic name for supply
1127  *
1128  * Allows platform initialisation code to map physical regulator
1129  * sources to symbolic names for supplies for use by devices.  Devices
1130  * should use these symbolic names to request regulators, avoiding the
1131  * need to provide board-specific regulator names as platform data.
1132  */
1133 static int set_consumer_device_supply(struct regulator_dev *rdev,
1134                                       const char *consumer_dev_name,
1135                                       const char *supply)
1136 {
1137         struct regulator_map *node;
1138         int has_dev;
1139
1140         if (supply == NULL)
1141                 return -EINVAL;
1142
1143         if (consumer_dev_name != NULL)
1144                 has_dev = 1;
1145         else
1146                 has_dev = 0;
1147
1148         list_for_each_entry(node, &regulator_map_list, list) {
1149                 if (node->dev_name && consumer_dev_name) {
1150                         if (strcmp(node->dev_name, consumer_dev_name) != 0)
1151                                 continue;
1152                 } else if (node->dev_name || consumer_dev_name) {
1153                         continue;
1154                 }
1155
1156                 if (strcmp(node->supply, supply) != 0)
1157                         continue;
1158
1159                 pr_debug("%s: %s/%s is '%s' supply; fail %s/%s\n",
1160                          consumer_dev_name,
1161                          dev_name(&node->regulator->dev),
1162                          node->regulator->desc->name,
1163                          supply,
1164                          dev_name(&rdev->dev), rdev_get_name(rdev));
1165                 return -EBUSY;
1166         }
1167
1168         node = kzalloc(sizeof(struct regulator_map), GFP_KERNEL);
1169         if (node == NULL)
1170                 return -ENOMEM;
1171
1172         node->regulator = rdev;
1173         node->supply = supply;
1174
1175         if (has_dev) {
1176                 node->dev_name = kstrdup(consumer_dev_name, GFP_KERNEL);
1177                 if (node->dev_name == NULL) {
1178                         kfree(node);
1179                         return -ENOMEM;
1180                 }
1181         }
1182
1183         list_add(&node->list, &regulator_map_list);
1184         return 0;
1185 }
1186
1187 static void unset_regulator_supplies(struct regulator_dev *rdev)
1188 {
1189         struct regulator_map *node, *n;
1190
1191         list_for_each_entry_safe(node, n, &regulator_map_list, list) {
1192                 if (rdev == node->regulator) {
1193                         list_del(&node->list);
1194                         kfree(node->dev_name);
1195                         kfree(node);
1196                 }
1197         }
1198 }
1199
1200 #define REG_STR_SIZE    64
1201
1202 static struct regulator *create_regulator(struct regulator_dev *rdev,
1203                                           struct device *dev,
1204                                           const char *supply_name)
1205 {
1206         struct regulator *regulator;
1207         char buf[REG_STR_SIZE];
1208         int err, size;
1209
1210         regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
1211         if (regulator == NULL)
1212                 return NULL;
1213
1214         mutex_lock(&rdev->mutex);
1215         regulator->rdev = rdev;
1216         list_add(&regulator->list, &rdev->consumer_list);
1217
1218         if (dev) {
1219                 regulator->dev = dev;
1220
1221                 /* Add a link to the device sysfs entry */
1222                 size = scnprintf(buf, REG_STR_SIZE, "%s-%s",
1223                                  dev->kobj.name, supply_name);
1224                 if (size >= REG_STR_SIZE)
1225                         goto overflow_err;
1226
1227                 regulator->supply_name = kstrdup(buf, GFP_KERNEL);
1228                 if (regulator->supply_name == NULL)
1229                         goto overflow_err;
1230
1231                 err = sysfs_create_link_nowarn(&rdev->dev.kobj, &dev->kobj,
1232                                         buf);
1233                 if (err) {
1234                         rdev_dbg(rdev, "could not add device link %s err %d\n",
1235                                   dev->kobj.name, err);
1236                         /* non-fatal */
1237                 }
1238         } else {
1239                 regulator->supply_name = kstrdup(supply_name, GFP_KERNEL);
1240                 if (regulator->supply_name == NULL)
1241                         goto overflow_err;
1242         }
1243
1244         regulator->debugfs = debugfs_create_dir(regulator->supply_name,
1245                                                 rdev->debugfs);
1246         if (!regulator->debugfs) {
1247                 rdev_warn(rdev, "Failed to create debugfs directory\n");
1248         } else {
1249                 debugfs_create_u32("uA_load", 0444, regulator->debugfs,
1250                                    &regulator->uA_load);
1251                 debugfs_create_u32("min_uV", 0444, regulator->debugfs,
1252                                    &regulator->min_uV);
1253                 debugfs_create_u32("max_uV", 0444, regulator->debugfs,
1254                                    &regulator->max_uV);
1255         }
1256
1257         /*
1258          * Check now if the regulator is an always on regulator - if
1259          * it is then we don't need to do nearly so much work for
1260          * enable/disable calls.
1261          */
1262         if (!_regulator_can_change_status(rdev) &&
1263             _regulator_is_enabled(rdev))
1264                 regulator->always_on = true;
1265
1266         mutex_unlock(&rdev->mutex);
1267         return regulator;
1268 overflow_err:
1269         list_del(&regulator->list);
1270         kfree(regulator);
1271         mutex_unlock(&rdev->mutex);
1272         return NULL;
1273 }
1274
1275 static int _regulator_get_enable_time(struct regulator_dev *rdev)
1276 {
1277         if (rdev->constraints && rdev->constraints->enable_time)
1278                 return rdev->constraints->enable_time;
1279         if (!rdev->desc->ops->enable_time)
1280                 return rdev->desc->enable_time;
1281         return rdev->desc->ops->enable_time(rdev);
1282 }
1283
1284 static struct regulator_supply_alias *regulator_find_supply_alias(
1285                 struct device *dev, const char *supply)
1286 {
1287         struct regulator_supply_alias *map;
1288
1289         list_for_each_entry(map, &regulator_supply_alias_list, list)
1290                 if (map->src_dev == dev && strcmp(map->src_supply, supply) == 0)
1291                         return map;
1292
1293         return NULL;
1294 }
1295
1296 static void regulator_supply_alias(struct device **dev, const char **supply)
1297 {
1298         struct regulator_supply_alias *map;
1299
1300         map = regulator_find_supply_alias(*dev, *supply);
1301         if (map) {
1302                 dev_dbg(*dev, "Mapping supply %s to %s,%s\n",
1303                                 *supply, map->alias_supply,
1304                                 dev_name(map->alias_dev));
1305                 *dev = map->alias_dev;
1306                 *supply = map->alias_supply;
1307         }
1308 }
1309
1310 static struct regulator_dev *regulator_dev_lookup(struct device *dev,
1311                                                   const char *supply,
1312                                                   int *ret)
1313 {
1314         struct regulator_dev *r;
1315         struct device_node *node;
1316         struct regulator_map *map;
1317         const char *devname = NULL;
1318
1319         regulator_supply_alias(&dev, &supply);
1320
1321         /* first do a dt based lookup */
1322         if (dev && dev->of_node) {
1323                 node = of_get_regulator(dev, supply);
1324                 if (node) {
1325                         list_for_each_entry(r, &regulator_list, list)
1326                                 if (r->dev.parent &&
1327                                         node == r->dev.of_node)
1328                                         return r;
1329                         *ret = -EPROBE_DEFER;
1330                         return NULL;
1331                 } else {
1332                         /*
1333                          * If we couldn't even get the node then it's
1334                          * not just that the device didn't register
1335                          * yet, there's no node and we'll never
1336                          * succeed.
1337                          */
1338                         *ret = -ENODEV;
1339                 }
1340         }
1341
1342         /* if not found, try doing it non-dt way */
1343         if (dev)
1344                 devname = dev_name(dev);
1345
1346         list_for_each_entry(r, &regulator_list, list)
1347                 if (strcmp(rdev_get_name(r), supply) == 0)
1348                         return r;
1349
1350         list_for_each_entry(map, &regulator_map_list, list) {
1351                 /* If the mapping has a device set up it must match */
1352                 if (map->dev_name &&
1353                     (!devname || strcmp(map->dev_name, devname)))
1354                         continue;
1355
1356                 if (strcmp(map->supply, supply) == 0)
1357                         return map->regulator;
1358         }
1359
1360
1361         return NULL;
1362 }
1363
1364 static int regulator_resolve_supply(struct regulator_dev *rdev)
1365 {
1366         struct regulator_dev *r;
1367         struct device *dev = rdev->dev.parent;
1368         int ret;
1369
1370         /* No supply to resovle? */
1371         if (!rdev->supply_name)
1372                 return 0;
1373
1374         /* Supply already resolved? */
1375         if (rdev->supply)
1376                 return 0;
1377
1378         r = regulator_dev_lookup(dev, rdev->supply_name, &ret);
1379         if (ret == -ENODEV) {
1380                 /*
1381                  * No supply was specified for this regulator and
1382                  * there will never be one.
1383                  */
1384                 return 0;
1385         }
1386
1387         if (!r) {
1388                 if (have_full_constraints()) {
1389                         r = dummy_regulator_rdev;
1390                 } else {
1391                         dev_err(dev, "Failed to resolve %s-supply for %s\n",
1392                                 rdev->supply_name, rdev->desc->name);
1393                         return -EPROBE_DEFER;
1394                 }
1395         }
1396
1397         /* Recursively resolve the supply of the supply */
1398         ret = regulator_resolve_supply(r);
1399         if (ret < 0)
1400                 return ret;
1401
1402         ret = set_supply(rdev, r);
1403         if (ret < 0)
1404                 return ret;
1405
1406         /* Cascade always-on state to supply */
1407         if (_regulator_is_enabled(rdev)) {
1408                 ret = regulator_enable(rdev->supply);
1409                 if (ret < 0) {
1410                         if (rdev->supply)
1411                                 _regulator_put(rdev->supply);
1412                         return ret;
1413                 }
1414         }
1415
1416         return 0;
1417 }
1418
1419 /* Internal regulator request function */
1420 static struct regulator *_regulator_get(struct device *dev, const char *id,
1421                                         bool exclusive, bool allow_dummy)
1422 {
1423         struct regulator_dev *rdev;
1424         struct regulator *regulator = ERR_PTR(-EPROBE_DEFER);
1425         const char *devname = NULL;
1426         int ret;
1427
1428         if (id == NULL) {
1429                 pr_err("get() with no identifier\n");
1430                 return ERR_PTR(-EINVAL);
1431         }
1432
1433         if (dev)
1434                 devname = dev_name(dev);
1435
1436         if (have_full_constraints())
1437                 ret = -ENODEV;
1438         else
1439                 ret = -EPROBE_DEFER;
1440
1441         mutex_lock(&regulator_list_mutex);
1442
1443         rdev = regulator_dev_lookup(dev, id, &ret);
1444         if (rdev)
1445                 goto found;
1446
1447         regulator = ERR_PTR(ret);
1448
1449         /*
1450          * If we have return value from dev_lookup fail, we do not expect to
1451          * succeed, so, quit with appropriate error value
1452          */
1453         if (ret && ret != -ENODEV)
1454                 goto out;
1455
1456         if (!devname)
1457                 devname = "deviceless";
1458
1459         /*
1460          * Assume that a regulator is physically present and enabled
1461          * even if it isn't hooked up and just provide a dummy.
1462          */
1463         if (have_full_constraints() && allow_dummy) {
1464                 pr_warn("%s supply %s not found, using dummy regulator\n",
1465                         devname, id);
1466
1467                 rdev = dummy_regulator_rdev;
1468                 goto found;
1469         /* Don't log an error when called from regulator_get_optional() */
1470         } else if (!have_full_constraints() || exclusive) {
1471                 dev_warn(dev, "dummy supplies not allowed\n");
1472         }
1473
1474         mutex_unlock(&regulator_list_mutex);
1475         return regulator;
1476
1477 found:
1478         if (rdev->exclusive) {
1479                 regulator = ERR_PTR(-EPERM);
1480                 goto out;
1481         }
1482
1483         if (exclusive && rdev->open_count) {
1484                 regulator = ERR_PTR(-EBUSY);
1485                 goto out;
1486         }
1487
1488         ret = regulator_resolve_supply(rdev);
1489         if (ret < 0) {
1490                 regulator = ERR_PTR(ret);
1491                 goto out;
1492         }
1493
1494         if (!try_module_get(rdev->owner))
1495                 goto out;
1496
1497         regulator = create_regulator(rdev, dev, id);
1498         if (regulator == NULL) {
1499                 regulator = ERR_PTR(-ENOMEM);
1500                 module_put(rdev->owner);
1501                 goto out;
1502         }
1503
1504         rdev->open_count++;
1505         if (exclusive) {
1506                 rdev->exclusive = 1;
1507
1508                 ret = _regulator_is_enabled(rdev);
1509                 if (ret > 0)
1510                         rdev->use_count = 1;
1511                 else
1512                         rdev->use_count = 0;
1513         }
1514
1515 out:
1516         mutex_unlock(&regulator_list_mutex);
1517
1518         return regulator;
1519 }
1520
1521 /**
1522  * regulator_get - lookup and obtain a reference to a regulator.
1523  * @dev: device for regulator "consumer"
1524  * @id: Supply name or regulator ID.
1525  *
1526  * Returns a struct regulator corresponding to the regulator producer,
1527  * or IS_ERR() condition containing errno.
1528  *
1529  * Use of supply names configured via regulator_set_device_supply() is
1530  * strongly encouraged.  It is recommended that the supply name used
1531  * should match the name used for the supply and/or the relevant
1532  * device pins in the datasheet.
1533  */
1534 struct regulator *regulator_get(struct device *dev, const char *id)
1535 {
1536         return _regulator_get(dev, id, false, true);
1537 }
1538 EXPORT_SYMBOL_GPL(regulator_get);
1539
1540 /**
1541  * regulator_get_exclusive - obtain exclusive access to a regulator.
1542  * @dev: device for regulator "consumer"
1543  * @id: Supply name or regulator ID.
1544  *
1545  * Returns a struct regulator corresponding to the regulator producer,
1546  * or IS_ERR() condition containing errno.  Other consumers will be
1547  * unable to obtain this regulator while this reference is held and the
1548  * use count for the regulator will be initialised to reflect the current
1549  * state of the regulator.
1550  *
1551  * This is intended for use by consumers which cannot tolerate shared
1552  * use of the regulator such as those which need to force the
1553  * regulator off for correct operation of the hardware they are
1554  * controlling.
1555  *
1556  * Use of supply names configured via regulator_set_device_supply() is
1557  * strongly encouraged.  It is recommended that the supply name used
1558  * should match the name used for the supply and/or the relevant
1559  * device pins in the datasheet.
1560  */
1561 struct regulator *regulator_get_exclusive(struct device *dev, const char *id)
1562 {
1563         return _regulator_get(dev, id, true, false);
1564 }
1565 EXPORT_SYMBOL_GPL(regulator_get_exclusive);
1566
1567 /**
1568  * regulator_get_optional - obtain optional access to a regulator.
1569  * @dev: device for regulator "consumer"
1570  * @id: Supply name or regulator ID.
1571  *
1572  * Returns a struct regulator corresponding to the regulator producer,
1573  * or IS_ERR() condition containing errno.
1574  *
1575  * This is intended for use by consumers for devices which can have
1576  * some supplies unconnected in normal use, such as some MMC devices.
1577  * It can allow the regulator core to provide stub supplies for other
1578  * supplies requested using normal regulator_get() calls without
1579  * disrupting the operation of drivers that can handle absent
1580  * supplies.
1581  *
1582  * Use of supply names configured via regulator_set_device_supply() is
1583  * strongly encouraged.  It is recommended that the supply name used
1584  * should match the name used for the supply and/or the relevant
1585  * device pins in the datasheet.
1586  */
1587 struct regulator *regulator_get_optional(struct device *dev, const char *id)
1588 {
1589         return _regulator_get(dev, id, false, false);
1590 }
1591 EXPORT_SYMBOL_GPL(regulator_get_optional);
1592
1593 /* regulator_list_mutex lock held by regulator_put() */
1594 static void _regulator_put(struct regulator *regulator)
1595 {
1596         struct regulator_dev *rdev;
1597
1598         if (regulator == NULL || IS_ERR(regulator))
1599                 return;
1600
1601         rdev = regulator->rdev;
1602
1603         debugfs_remove_recursive(regulator->debugfs);
1604
1605         /* remove any sysfs entries */
1606         if (regulator->dev)
1607                 sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
1608         mutex_lock(&rdev->mutex);
1609         kfree(regulator->supply_name);
1610         list_del(&regulator->list);
1611         kfree(regulator);
1612
1613         rdev->open_count--;
1614         rdev->exclusive = 0;
1615         mutex_unlock(&rdev->mutex);
1616
1617         module_put(rdev->owner);
1618 }
1619
1620 /**
1621  * regulator_put - "free" the regulator source
1622  * @regulator: regulator source
1623  *
1624  * Note: drivers must ensure that all regulator_enable calls made on this
1625  * regulator source are balanced by regulator_disable calls prior to calling
1626  * this function.
1627  */
1628 void regulator_put(struct regulator *regulator)
1629 {
1630         mutex_lock(&regulator_list_mutex);
1631         _regulator_put(regulator);
1632         mutex_unlock(&regulator_list_mutex);
1633 }
1634 EXPORT_SYMBOL_GPL(regulator_put);
1635
1636 /**
1637  * regulator_register_supply_alias - Provide device alias for supply lookup
1638  *
1639  * @dev: device that will be given as the regulator "consumer"
1640  * @id: Supply name or regulator ID
1641  * @alias_dev: device that should be used to lookup the supply
1642  * @alias_id: Supply name or regulator ID that should be used to lookup the
1643  * supply
1644  *
1645  * All lookups for id on dev will instead be conducted for alias_id on
1646  * alias_dev.
1647  */
1648 int regulator_register_supply_alias(struct device *dev, const char *id,
1649                                     struct device *alias_dev,
1650                                     const char *alias_id)
1651 {
1652         struct regulator_supply_alias *map;
1653
1654         map = regulator_find_supply_alias(dev, id);
1655         if (map)
1656                 return -EEXIST;
1657
1658         map = kzalloc(sizeof(struct regulator_supply_alias), GFP_KERNEL);
1659         if (!map)
1660                 return -ENOMEM;
1661
1662         map->src_dev = dev;
1663         map->src_supply = id;
1664         map->alias_dev = alias_dev;
1665         map->alias_supply = alias_id;
1666
1667         list_add(&map->list, &regulator_supply_alias_list);
1668
1669         pr_info("Adding alias for supply %s,%s -> %s,%s\n",
1670                 id, dev_name(dev), alias_id, dev_name(alias_dev));
1671
1672         return 0;
1673 }
1674 EXPORT_SYMBOL_GPL(regulator_register_supply_alias);
1675
1676 /**
1677  * regulator_unregister_supply_alias - Remove device alias
1678  *
1679  * @dev: device that will be given as the regulator "consumer"
1680  * @id: Supply name or regulator ID
1681  *
1682  * Remove a lookup alias if one exists for id on dev.
1683  */
1684 void regulator_unregister_supply_alias(struct device *dev, const char *id)
1685 {
1686         struct regulator_supply_alias *map;
1687
1688         map = regulator_find_supply_alias(dev, id);
1689         if (map) {
1690                 list_del(&map->list);
1691                 kfree(map);
1692         }
1693 }
1694 EXPORT_SYMBOL_GPL(regulator_unregister_supply_alias);
1695
1696 /**
1697  * regulator_bulk_register_supply_alias - register multiple aliases
1698  *
1699  * @dev: device that will be given as the regulator "consumer"
1700  * @id: List of supply names or regulator IDs
1701  * @alias_dev: device that should be used to lookup the supply
1702  * @alias_id: List of supply names or regulator IDs that should be used to
1703  * lookup the supply
1704  * @num_id: Number of aliases to register
1705  *
1706  * @return 0 on success, an errno on failure.
1707  *
1708  * This helper function allows drivers to register several supply
1709  * aliases in one operation.  If any of the aliases cannot be
1710  * registered any aliases that were registered will be removed
1711  * before returning to the caller.
1712  */
1713 int regulator_bulk_register_supply_alias(struct device *dev,
1714                                          const char *const *id,
1715                                          struct device *alias_dev,
1716                                          const char *const *alias_id,
1717                                          int num_id)
1718 {
1719         int i;
1720         int ret;
1721
1722         for (i = 0; i < num_id; ++i) {
1723                 ret = regulator_register_supply_alias(dev, id[i], alias_dev,
1724                                                       alias_id[i]);
1725                 if (ret < 0)
1726                         goto err;
1727         }
1728
1729         return 0;
1730
1731 err:
1732         dev_err(dev,
1733                 "Failed to create supply alias %s,%s -> %s,%s\n",
1734                 id[i], dev_name(dev), alias_id[i], dev_name(alias_dev));
1735
1736         while (--i >= 0)
1737                 regulator_unregister_supply_alias(dev, id[i]);
1738
1739         return ret;
1740 }
1741 EXPORT_SYMBOL_GPL(regulator_bulk_register_supply_alias);
1742
1743 /**
1744  * regulator_bulk_unregister_supply_alias - unregister multiple aliases
1745  *
1746  * @dev: device that will be given as the regulator "consumer"
1747  * @id: List of supply names or regulator IDs
1748  * @num_id: Number of aliases to unregister
1749  *
1750  * This helper function allows drivers to unregister several supply
1751  * aliases in one operation.
1752  */
1753 void regulator_bulk_unregister_supply_alias(struct device *dev,
1754                                             const char *const *id,
1755                                             int num_id)
1756 {
1757         int i;
1758
1759         for (i = 0; i < num_id; ++i)
1760                 regulator_unregister_supply_alias(dev, id[i]);
1761 }
1762 EXPORT_SYMBOL_GPL(regulator_bulk_unregister_supply_alias);
1763
1764
1765 /* Manage enable GPIO list. Same GPIO pin can be shared among regulators */
1766 static int regulator_ena_gpio_request(struct regulator_dev *rdev,
1767                                 const struct regulator_config *config)
1768 {
1769         struct regulator_enable_gpio *pin;
1770         struct gpio_desc *gpiod;
1771         int ret;
1772
1773         gpiod = gpio_to_desc(config->ena_gpio);
1774
1775         list_for_each_entry(pin, &regulator_ena_gpio_list, list) {
1776                 if (pin->gpiod == gpiod) {
1777                         rdev_dbg(rdev, "GPIO %d is already used\n",
1778                                 config->ena_gpio);
1779                         goto update_ena_gpio_to_rdev;
1780                 }
1781         }
1782
1783         ret = gpio_request_one(config->ena_gpio,
1784                                 GPIOF_DIR_OUT | config->ena_gpio_flags,
1785                                 rdev_get_name(rdev));
1786         if (ret)
1787                 return ret;
1788
1789         pin = kzalloc(sizeof(struct regulator_enable_gpio), GFP_KERNEL);
1790         if (pin == NULL) {
1791                 gpio_free(config->ena_gpio);
1792                 return -ENOMEM;
1793         }
1794
1795         pin->gpiod = gpiod;
1796         pin->ena_gpio_invert = config->ena_gpio_invert;
1797         list_add(&pin->list, &regulator_ena_gpio_list);
1798
1799 update_ena_gpio_to_rdev:
1800         pin->request_count++;
1801         rdev->ena_pin = pin;
1802         return 0;
1803 }
1804
1805 static void regulator_ena_gpio_free(struct regulator_dev *rdev)
1806 {
1807         struct regulator_enable_gpio *pin, *n;
1808
1809         if (!rdev->ena_pin)
1810                 return;
1811
1812         /* Free the GPIO only in case of no use */
1813         list_for_each_entry_safe(pin, n, &regulator_ena_gpio_list, list) {
1814                 if (pin->gpiod == rdev->ena_pin->gpiod) {
1815                         if (pin->request_count <= 1) {
1816                                 pin->request_count = 0;
1817                                 gpiod_put(pin->gpiod);
1818                                 list_del(&pin->list);
1819                                 kfree(pin);
1820                                 rdev->ena_pin = NULL;
1821                                 return;
1822                         } else {
1823                                 pin->request_count--;
1824                         }
1825                 }
1826         }
1827 }
1828
1829 /**
1830  * regulator_ena_gpio_ctrl - balance enable_count of each GPIO and actual GPIO pin control
1831  * @rdev: regulator_dev structure
1832  * @enable: enable GPIO at initial use?
1833  *
1834  * GPIO is enabled in case of initial use. (enable_count is 0)
1835  * GPIO is disabled when it is not shared any more. (enable_count <= 1)
1836  */
1837 static int regulator_ena_gpio_ctrl(struct regulator_dev *rdev, bool enable)
1838 {
1839         struct regulator_enable_gpio *pin = rdev->ena_pin;
1840
1841         if (!pin)
1842                 return -EINVAL;
1843
1844         if (enable) {
1845                 /* Enable GPIO at initial use */
1846                 if (pin->enable_count == 0)
1847                         gpiod_set_value_cansleep(pin->gpiod,
1848                                                  !pin->ena_gpio_invert);
1849
1850                 pin->enable_count++;
1851         } else {
1852                 if (pin->enable_count > 1) {
1853                         pin->enable_count--;
1854                         return 0;
1855                 }
1856
1857                 /* Disable GPIO if not used */
1858                 if (pin->enable_count <= 1) {
1859                         gpiod_set_value_cansleep(pin->gpiod,
1860                                                  pin->ena_gpio_invert);
1861                         pin->enable_count = 0;
1862                 }
1863         }
1864
1865         return 0;
1866 }
1867
1868 /**
1869  * _regulator_enable_delay - a delay helper function
1870  * @delay: time to delay in microseconds
1871  *
1872  * Delay for the requested amount of time as per the guidelines in:
1873  *
1874  *     Documentation/timers/timers-howto.txt
1875  *
1876  * The assumption here is that regulators will never be enabled in
1877  * atomic context and therefore sleeping functions can be used.
1878  */
1879 static void _regulator_enable_delay(unsigned int delay)
1880 {
1881         unsigned int ms = delay / 1000;
1882         unsigned int us = delay % 1000;
1883
1884         if (ms > 0) {
1885                 /*
1886                  * For small enough values, handle super-millisecond
1887                  * delays in the usleep_range() call below.
1888                  */
1889                 if (ms < 20)
1890                         us += ms * 1000;
1891                 else
1892                         msleep(ms);
1893         }
1894
1895         /*
1896          * Give the scheduler some room to coalesce with any other
1897          * wakeup sources. For delays shorter than 10 us, don't even
1898          * bother setting up high-resolution timers and just busy-
1899          * loop.
1900          */
1901         if (us >= 10)
1902                 usleep_range(us, us + 100);
1903         else
1904                 udelay(us);
1905 }
1906
1907 static int _regulator_do_enable(struct regulator_dev *rdev)
1908 {
1909         int ret, delay;
1910
1911         /* Query before enabling in case configuration dependent.  */
1912         ret = _regulator_get_enable_time(rdev);
1913         if (ret >= 0) {
1914                 delay = ret;
1915         } else {
1916                 rdev_warn(rdev, "enable_time() failed: %d\n", ret);
1917                 delay = 0;
1918         }
1919
1920         trace_regulator_enable(rdev_get_name(rdev));
1921
1922         if (rdev->desc->off_on_delay) {
1923                 /* if needed, keep a distance of off_on_delay from last time
1924                  * this regulator was disabled.
1925                  */
1926                 unsigned long start_jiffy = jiffies;
1927                 unsigned long intended, max_delay, remaining;
1928
1929                 max_delay = usecs_to_jiffies(rdev->desc->off_on_delay);
1930                 intended = rdev->last_off_jiffy + max_delay;
1931
1932                 if (time_before(start_jiffy, intended)) {
1933                         /* calc remaining jiffies to deal with one-time
1934                          * timer wrapping.
1935                          * in case of multiple timer wrapping, either it can be
1936                          * detected by out-of-range remaining, or it cannot be
1937                          * detected and we gets a panelty of
1938                          * _regulator_enable_delay().
1939                          */
1940                         remaining = intended - start_jiffy;
1941                         if (remaining <= max_delay)
1942                                 _regulator_enable_delay(
1943                                                 jiffies_to_usecs(remaining));
1944                 }
1945         }
1946
1947         if (rdev->ena_pin) {
1948                 if (!rdev->ena_gpio_state) {
1949                         ret = regulator_ena_gpio_ctrl(rdev, true);
1950                         if (ret < 0)
1951                                 return ret;
1952                         rdev->ena_gpio_state = 1;
1953                 }
1954         } else if (rdev->desc->ops->enable) {
1955                 ret = rdev->desc->ops->enable(rdev);
1956                 if (ret < 0)
1957                         return ret;
1958         } else {
1959                 return -EINVAL;
1960         }
1961
1962         /* Allow the regulator to ramp; it would be useful to extend
1963          * this for bulk operations so that the regulators can ramp
1964          * together.  */
1965         trace_regulator_enable_delay(rdev_get_name(rdev));
1966
1967         _regulator_enable_delay(delay);
1968
1969         trace_regulator_enable_complete(rdev_get_name(rdev));
1970
1971         return 0;
1972 }
1973
1974 /* locks held by regulator_enable() */
1975 static int _regulator_enable(struct regulator_dev *rdev)
1976 {
1977         int ret;
1978
1979         /* check voltage and requested load before enabling */
1980         if (rdev->constraints &&
1981             (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS))
1982                 drms_uA_update(rdev);
1983
1984         if (rdev->use_count == 0) {
1985                 /* The regulator may on if it's not switchable or left on */
1986                 ret = _regulator_is_enabled(rdev);
1987                 if (ret == -EINVAL || ret == 0) {
1988                         if (!_regulator_can_change_status(rdev))
1989                                 return -EPERM;
1990
1991                         ret = _regulator_do_enable(rdev);
1992                         if (ret < 0)
1993                                 return ret;
1994
1995                 } else if (ret < 0) {
1996                         rdev_err(rdev, "is_enabled() failed: %d\n", ret);
1997                         return ret;
1998                 }
1999                 /* Fallthrough on positive return values - already enabled */
2000         }
2001
2002         rdev->use_count++;
2003
2004         return 0;
2005 }
2006
2007 /**
2008  * regulator_enable - enable regulator output
2009  * @regulator: regulator source
2010  *
2011  * Request that the regulator be enabled with the regulator output at
2012  * the predefined voltage or current value.  Calls to regulator_enable()
2013  * must be balanced with calls to regulator_disable().
2014  *
2015  * NOTE: the output value can be set by other drivers, boot loader or may be
2016  * hardwired in the regulator.
2017  */
2018 int regulator_enable(struct regulator *regulator)
2019 {
2020         struct regulator_dev *rdev = regulator->rdev;
2021         int ret = 0;
2022
2023         if (regulator->always_on)
2024                 return 0;
2025
2026         if (rdev->supply) {
2027                 ret = regulator_enable(rdev->supply);
2028                 if (ret != 0)
2029                         return ret;
2030         }
2031
2032         mutex_lock(&rdev->mutex);
2033         ret = _regulator_enable(rdev);
2034         mutex_unlock(&rdev->mutex);
2035
2036         if (ret != 0 && rdev->supply)
2037                 regulator_disable(rdev->supply);
2038
2039         return ret;
2040 }
2041 EXPORT_SYMBOL_GPL(regulator_enable);
2042
2043 static int _regulator_do_disable(struct regulator_dev *rdev)
2044 {
2045         int ret;
2046
2047         trace_regulator_disable(rdev_get_name(rdev));
2048
2049         if (rdev->ena_pin) {
2050                 if (rdev->ena_gpio_state) {
2051                         ret = regulator_ena_gpio_ctrl(rdev, false);
2052                         if (ret < 0)
2053                                 return ret;
2054                         rdev->ena_gpio_state = 0;
2055                 }
2056
2057         } else if (rdev->desc->ops->disable) {
2058                 ret = rdev->desc->ops->disable(rdev);
2059                 if (ret != 0)
2060                         return ret;
2061         }
2062
2063         /* cares about last_off_jiffy only if off_on_delay is required by
2064          * device.
2065          */
2066         if (rdev->desc->off_on_delay)
2067                 rdev->last_off_jiffy = jiffies;
2068
2069         trace_regulator_disable_complete(rdev_get_name(rdev));
2070
2071         return 0;
2072 }
2073
2074 /* locks held by regulator_disable() */
2075 static int _regulator_disable(struct regulator_dev *rdev)
2076 {
2077         int ret = 0;
2078
2079         if (WARN(rdev->use_count <= 0,
2080                  "unbalanced disables for %s\n", rdev_get_name(rdev)))
2081                 return -EIO;
2082
2083         /* are we the last user and permitted to disable ? */
2084         if (rdev->use_count == 1 &&
2085             (rdev->constraints && !rdev->constraints->always_on)) {
2086
2087                 /* we are last user */
2088                 if (_regulator_can_change_status(rdev)) {
2089                         ret = _notifier_call_chain(rdev,
2090                                                    REGULATOR_EVENT_PRE_DISABLE,
2091                                                    NULL);
2092                         if (ret & NOTIFY_STOP_MASK)
2093                                 return -EINVAL;
2094
2095                         ret = _regulator_do_disable(rdev);
2096                         if (ret < 0) {
2097                                 rdev_err(rdev, "failed to disable\n");
2098                                 _notifier_call_chain(rdev,
2099                                                 REGULATOR_EVENT_ABORT_DISABLE,
2100                                                 NULL);
2101                                 return ret;
2102                         }
2103                         _notifier_call_chain(rdev, REGULATOR_EVENT_DISABLE,
2104                                         NULL);
2105                 }
2106
2107                 rdev->use_count = 0;
2108         } else if (rdev->use_count > 1) {
2109
2110                 if (rdev->constraints &&
2111                         (rdev->constraints->valid_ops_mask &
2112                         REGULATOR_CHANGE_DRMS))
2113                         drms_uA_update(rdev);
2114
2115                 rdev->use_count--;
2116         }
2117
2118         return ret;
2119 }
2120
2121 /**
2122  * regulator_disable - disable regulator output
2123  * @regulator: regulator source
2124  *
2125  * Disable the regulator output voltage or current.  Calls to
2126  * regulator_enable() must be balanced with calls to
2127  * regulator_disable().
2128  *
2129  * NOTE: this will only disable the regulator output if no other consumer
2130  * devices have it enabled, the regulator device supports disabling and
2131  * machine constraints permit this operation.
2132  */
2133 int regulator_disable(struct regulator *regulator)
2134 {
2135         struct regulator_dev *rdev = regulator->rdev;
2136         int ret = 0;
2137
2138         if (regulator->always_on)
2139                 return 0;
2140
2141         mutex_lock(&rdev->mutex);
2142         ret = _regulator_disable(rdev);
2143         mutex_unlock(&rdev->mutex);
2144
2145         if (ret == 0 && rdev->supply)
2146                 regulator_disable(rdev->supply);
2147
2148         return ret;
2149 }
2150 EXPORT_SYMBOL_GPL(regulator_disable);
2151
2152 /* locks held by regulator_force_disable() */
2153 static int _regulator_force_disable(struct regulator_dev *rdev)
2154 {
2155         int ret = 0;
2156
2157         ret = _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
2158                         REGULATOR_EVENT_PRE_DISABLE, NULL);
2159         if (ret & NOTIFY_STOP_MASK)
2160                 return -EINVAL;
2161
2162         ret = _regulator_do_disable(rdev);
2163         if (ret < 0) {
2164                 rdev_err(rdev, "failed to force disable\n");
2165                 _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
2166                                 REGULATOR_EVENT_ABORT_DISABLE, NULL);
2167                 return ret;
2168         }
2169
2170         _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
2171                         REGULATOR_EVENT_DISABLE, NULL);
2172
2173         return 0;
2174 }
2175
2176 /**
2177  * regulator_force_disable - force disable regulator output
2178  * @regulator: regulator source
2179  *
2180  * Forcibly disable the regulator output voltage or current.
2181  * NOTE: this *will* disable the regulator output even if other consumer
2182  * devices have it enabled. This should be used for situations when device
2183  * damage will likely occur if the regulator is not disabled (e.g. over temp).
2184  */
2185 int regulator_force_disable(struct regulator *regulator)
2186 {
2187         struct regulator_dev *rdev = regulator->rdev;
2188         int ret;
2189
2190         mutex_lock(&rdev->mutex);
2191         regulator->uA_load = 0;
2192         ret = _regulator_force_disable(regulator->rdev);
2193         mutex_unlock(&rdev->mutex);
2194
2195         if (rdev->supply)
2196                 while (rdev->open_count--)
2197                         regulator_disable(rdev->supply);
2198
2199         return ret;
2200 }
2201 EXPORT_SYMBOL_GPL(regulator_force_disable);
2202
2203 static void regulator_disable_work(struct work_struct *work)
2204 {
2205         struct regulator_dev *rdev = container_of(work, struct regulator_dev,
2206                                                   disable_work.work);
2207         int count, i, ret;
2208
2209         mutex_lock(&rdev->mutex);
2210
2211         BUG_ON(!rdev->deferred_disables);
2212
2213         count = rdev->deferred_disables;
2214         rdev->deferred_disables = 0;
2215
2216         for (i = 0; i < count; i++) {
2217                 ret = _regulator_disable(rdev);
2218                 if (ret != 0)
2219                         rdev_err(rdev, "Deferred disable failed: %d\n", ret);
2220         }
2221
2222         mutex_unlock(&rdev->mutex);
2223
2224         if (rdev->supply) {
2225                 for (i = 0; i < count; i++) {
2226                         ret = regulator_disable(rdev->supply);
2227                         if (ret != 0) {
2228                                 rdev_err(rdev,
2229                                          "Supply disable failed: %d\n", ret);
2230                         }
2231                 }
2232         }
2233 }
2234
2235 /**
2236  * regulator_disable_deferred - disable regulator output with delay
2237  * @regulator: regulator source
2238  * @ms: miliseconds until the regulator is disabled
2239  *
2240  * Execute regulator_disable() on the regulator after a delay.  This
2241  * is intended for use with devices that require some time to quiesce.
2242  *
2243  * NOTE: this will only disable the regulator output if no other consumer
2244  * devices have it enabled, the regulator device supports disabling and
2245  * machine constraints permit this operation.
2246  */
2247 int regulator_disable_deferred(struct regulator *regulator, int ms)
2248 {
2249         struct regulator_dev *rdev = regulator->rdev;
2250         int ret;
2251
2252         if (regulator->always_on)
2253                 return 0;
2254
2255         if (!ms)
2256                 return regulator_disable(regulator);
2257
2258         mutex_lock(&rdev->mutex);
2259         rdev->deferred_disables++;
2260         mutex_unlock(&rdev->mutex);
2261
2262         ret = queue_delayed_work(system_power_efficient_wq,
2263                                  &rdev->disable_work,
2264                                  msecs_to_jiffies(ms));
2265         if (ret < 0)
2266                 return ret;
2267         else
2268                 return 0;
2269 }
2270 EXPORT_SYMBOL_GPL(regulator_disable_deferred);
2271
2272 static int _regulator_is_enabled(struct regulator_dev *rdev)
2273 {
2274         /* A GPIO control always takes precedence */
2275         if (rdev->ena_pin)
2276                 return rdev->ena_gpio_state;
2277
2278         /* If we don't know then assume that the regulator is always on */
2279         if (!rdev->desc->ops->is_enabled)
2280                 return 1;
2281
2282         return rdev->desc->ops->is_enabled(rdev);
2283 }
2284
2285 /**
2286  * regulator_is_enabled - is the regulator output enabled
2287  * @regulator: regulator source
2288  *
2289  * Returns positive if the regulator driver backing the source/client
2290  * has requested that the device be enabled, zero if it hasn't, else a
2291  * negative errno code.
2292  *
2293  * Note that the device backing this regulator handle can have multiple
2294  * users, so it might be enabled even if regulator_enable() was never
2295  * called for this particular source.
2296  */
2297 int regulator_is_enabled(struct regulator *regulator)
2298 {
2299         int ret;
2300
2301         if (regulator->always_on)
2302                 return 1;
2303
2304         mutex_lock(&regulator->rdev->mutex);
2305         ret = _regulator_is_enabled(regulator->rdev);
2306         mutex_unlock(&regulator->rdev->mutex);
2307
2308         return ret;
2309 }
2310 EXPORT_SYMBOL_GPL(regulator_is_enabled);
2311
2312 /**
2313  * regulator_can_change_voltage - check if regulator can change voltage
2314  * @regulator: regulator source
2315  *
2316  * Returns positive if the regulator driver backing the source/client
2317  * can change its voltage, false otherwise. Useful for detecting fixed
2318  * or dummy regulators and disabling voltage change logic in the client
2319  * driver.
2320  */
2321 int regulator_can_change_voltage(struct regulator *regulator)
2322 {
2323         struct regulator_dev    *rdev = regulator->rdev;
2324
2325         if (rdev->constraints &&
2326             (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
2327                 if (rdev->desc->n_voltages - rdev->desc->linear_min_sel > 1)
2328                         return 1;
2329
2330                 if (rdev->desc->continuous_voltage_range &&
2331                     rdev->constraints->min_uV && rdev->constraints->max_uV &&
2332                     rdev->constraints->min_uV != rdev->constraints->max_uV)
2333                         return 1;
2334         }
2335
2336         return 0;
2337 }
2338 EXPORT_SYMBOL_GPL(regulator_can_change_voltage);
2339
2340 /**
2341  * regulator_count_voltages - count regulator_list_voltage() selectors
2342  * @regulator: regulator source
2343  *
2344  * Returns number of selectors, or negative errno.  Selectors are
2345  * numbered starting at zero, and typically correspond to bitfields
2346  * in hardware registers.
2347  */
2348 int regulator_count_voltages(struct regulator *regulator)
2349 {
2350         struct regulator_dev    *rdev = regulator->rdev;
2351
2352         if (rdev->desc->n_voltages)
2353                 return rdev->desc->n_voltages;
2354
2355         if (!rdev->supply)
2356                 return -EINVAL;
2357
2358         return regulator_count_voltages(rdev->supply);
2359 }
2360 EXPORT_SYMBOL_GPL(regulator_count_voltages);
2361
2362 /**
2363  * regulator_list_voltage - enumerate supported voltages
2364  * @regulator: regulator source
2365  * @selector: identify voltage to list
2366  * Context: can sleep
2367  *
2368  * Returns a voltage that can be passed to @regulator_set_voltage(),
2369  * zero if this selector code can't be used on this system, or a
2370  * negative errno.
2371  */
2372 int regulator_list_voltage(struct regulator *regulator, unsigned selector)
2373 {
2374         struct regulator_dev *rdev = regulator->rdev;
2375         const struct regulator_ops *ops = rdev->desc->ops;
2376         int ret;
2377
2378         if (rdev->desc->fixed_uV && rdev->desc->n_voltages == 1 && !selector)
2379                 return rdev->desc->fixed_uV;
2380
2381         if (ops->list_voltage) {
2382                 if (selector >= rdev->desc->n_voltages)
2383                         return -EINVAL;
2384                 mutex_lock(&rdev->mutex);
2385                 ret = ops->list_voltage(rdev, selector);
2386                 mutex_unlock(&rdev->mutex);
2387         } else if (rdev->supply) {
2388                 ret = regulator_list_voltage(rdev->supply, selector);
2389         } else {
2390                 return -EINVAL;
2391         }
2392
2393         if (ret > 0) {
2394                 if (ret < rdev->constraints->min_uV)
2395                         ret = 0;
2396                 else if (ret > rdev->constraints->max_uV)
2397                         ret = 0;
2398         }
2399
2400         return ret;
2401 }
2402 EXPORT_SYMBOL_GPL(regulator_list_voltage);
2403
2404 /**
2405  * regulator_get_regmap - get the regulator's register map
2406  * @regulator: regulator source
2407  *
2408  * Returns the register map for the given regulator, or an ERR_PTR value
2409  * if the regulator doesn't use regmap.
2410  */
2411 struct regmap *regulator_get_regmap(struct regulator *regulator)
2412 {
2413         struct regmap *map = regulator->rdev->regmap;
2414
2415         return map ? map : ERR_PTR(-EOPNOTSUPP);
2416 }
2417
2418 /**
2419  * regulator_get_hardware_vsel_register - get the HW voltage selector register
2420  * @regulator: regulator source
2421  * @vsel_reg: voltage selector register, output parameter
2422  * @vsel_mask: mask for voltage selector bitfield, output parameter
2423  *
2424  * Returns the hardware register offset and bitmask used for setting the
2425  * regulator voltage. This might be useful when configuring voltage-scaling
2426  * hardware or firmware that can make I2C requests behind the kernel's back,
2427  * for example.
2428  *
2429  * On success, the output parameters @vsel_reg and @vsel_mask are filled in
2430  * and 0 is returned, otherwise a negative errno is returned.
2431  */
2432 int regulator_get_hardware_vsel_register(struct regulator *regulator,
2433                                          unsigned *vsel_reg,
2434                                          unsigned *vsel_mask)
2435 {
2436         struct regulator_dev *rdev = regulator->rdev;
2437         const struct regulator_ops *ops = rdev->desc->ops;
2438
2439         if (ops->set_voltage_sel != regulator_set_voltage_sel_regmap)
2440                 return -EOPNOTSUPP;
2441
2442          *vsel_reg = rdev->desc->vsel_reg;
2443          *vsel_mask = rdev->desc->vsel_mask;
2444
2445          return 0;
2446 }
2447 EXPORT_SYMBOL_GPL(regulator_get_hardware_vsel_register);
2448
2449 /**
2450  * regulator_list_hardware_vsel - get the HW-specific register value for a selector
2451  * @regulator: regulator source
2452  * @selector: identify voltage to list
2453  *
2454  * Converts the selector to a hardware-specific voltage selector that can be
2455  * directly written to the regulator registers. The address of the voltage
2456  * register can be determined by calling @regulator_get_hardware_vsel_register.
2457  *
2458  * On error a negative errno is returned.
2459  */
2460 int regulator_list_hardware_vsel(struct regulator *regulator,
2461                                  unsigned selector)
2462 {
2463         struct regulator_dev *rdev = regulator->rdev;
2464         const struct regulator_ops *ops = rdev->desc->ops;
2465
2466         if (selector >= rdev->desc->n_voltages)
2467                 return -EINVAL;
2468         if (ops->set_voltage_sel != regulator_set_voltage_sel_regmap)
2469                 return -EOPNOTSUPP;
2470
2471         return selector;
2472 }
2473 EXPORT_SYMBOL_GPL(regulator_list_hardware_vsel);
2474
2475 /**
2476  * regulator_get_linear_step - return the voltage step size between VSEL values
2477  * @regulator: regulator source
2478  *
2479  * Returns the voltage step size between VSEL values for linear
2480  * regulators, or return 0 if the regulator isn't a linear regulator.
2481  */
2482 unsigned int regulator_get_linear_step(struct regulator *regulator)
2483 {
2484         struct regulator_dev *rdev = regulator->rdev;
2485
2486         return rdev->desc->uV_step;
2487 }
2488 EXPORT_SYMBOL_GPL(regulator_get_linear_step);
2489
2490 /**
2491  * regulator_is_supported_voltage - check if a voltage range can be supported
2492  *
2493  * @regulator: Regulator to check.
2494  * @min_uV: Minimum required voltage in uV.
2495  * @max_uV: Maximum required voltage in uV.
2496  *
2497  * Returns a boolean or a negative error code.
2498  */
2499 int regulator_is_supported_voltage(struct regulator *regulator,
2500                                    int min_uV, int max_uV)
2501 {
2502         struct regulator_dev *rdev = regulator->rdev;
2503         int i, voltages, ret;
2504
2505         /* If we can't change voltage check the current voltage */
2506         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
2507                 ret = regulator_get_voltage(regulator);
2508                 if (ret >= 0)
2509                         return min_uV <= ret && ret <= max_uV;
2510                 else
2511                         return ret;
2512         }
2513
2514         /* Any voltage within constrains range is fine? */
2515         if (rdev->desc->continuous_voltage_range)
2516                 return min_uV >= rdev->constraints->min_uV &&
2517                                 max_uV <= rdev->constraints->max_uV;
2518
2519         ret = regulator_count_voltages(regulator);
2520         if (ret < 0)
2521                 return ret;
2522         voltages = ret;
2523
2524         for (i = 0; i < voltages; i++) {
2525                 ret = regulator_list_voltage(regulator, i);
2526
2527                 if (ret >= min_uV && ret <= max_uV)
2528                         return 1;
2529         }
2530
2531         return 0;
2532 }
2533 EXPORT_SYMBOL_GPL(regulator_is_supported_voltage);
2534
2535 static int _regulator_call_set_voltage(struct regulator_dev *rdev,
2536                                        int min_uV, int max_uV,
2537                                        unsigned *selector)
2538 {
2539         struct pre_voltage_change_data data;
2540         int ret;
2541
2542         data.old_uV = _regulator_get_voltage(rdev);
2543         data.min_uV = min_uV;
2544         data.max_uV = max_uV;
2545         ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE,
2546                                    &data);
2547         if (ret & NOTIFY_STOP_MASK)
2548                 return -EINVAL;
2549
2550         ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV, selector);
2551         if (ret >= 0)
2552                 return ret;
2553
2554         _notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE,
2555                              (void *)data.old_uV);
2556
2557         return ret;
2558 }
2559
2560 static int _regulator_call_set_voltage_sel(struct regulator_dev *rdev,
2561                                            int uV, unsigned selector)
2562 {
2563         struct pre_voltage_change_data data;
2564         int ret;
2565
2566         data.old_uV = _regulator_get_voltage(rdev);
2567         data.min_uV = uV;
2568         data.max_uV = uV;
2569         ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE,
2570                                    &data);
2571         if (ret & NOTIFY_STOP_MASK)
2572                 return -EINVAL;
2573
2574         ret = rdev->desc->ops->set_voltage_sel(rdev, selector);
2575         if (ret >= 0)
2576                 return ret;
2577
2578         _notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE,
2579                              (void *)data.old_uV);
2580
2581         return ret;
2582 }
2583
2584 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
2585                                      int min_uV, int max_uV)
2586 {
2587         int ret;
2588         int delay = 0;
2589         int best_val = 0;
2590         unsigned int selector;
2591         int old_selector = -1;
2592
2593         trace_regulator_set_voltage(rdev_get_name(rdev), min_uV, max_uV);
2594
2595         min_uV += rdev->constraints->uV_offset;
2596         max_uV += rdev->constraints->uV_offset;
2597
2598         /*
2599          * If we can't obtain the old selector there is not enough
2600          * info to call set_voltage_time_sel().
2601          */
2602         if (_regulator_is_enabled(rdev) &&
2603             rdev->desc->ops->set_voltage_time_sel &&
2604             rdev->desc->ops->get_voltage_sel) {
2605                 old_selector = rdev->desc->ops->get_voltage_sel(rdev);
2606                 if (old_selector < 0)
2607                         return old_selector;
2608         }
2609
2610         if (rdev->desc->ops->set_voltage) {
2611                 ret = _regulator_call_set_voltage(rdev, min_uV, max_uV,
2612                                                   &selector);
2613
2614                 if (ret >= 0) {
2615                         if (rdev->desc->ops->list_voltage)
2616                                 best_val = rdev->desc->ops->list_voltage(rdev,
2617                                                                          selector);
2618                         else
2619                                 best_val = _regulator_get_voltage(rdev);
2620                 }
2621
2622         } else if (rdev->desc->ops->set_voltage_sel) {
2623                 if (rdev->desc->ops->map_voltage) {
2624                         ret = rdev->desc->ops->map_voltage(rdev, min_uV,
2625                                                            max_uV);
2626                 } else {
2627                         if (rdev->desc->ops->list_voltage ==
2628                             regulator_list_voltage_linear)
2629                                 ret = regulator_map_voltage_linear(rdev,
2630                                                                 min_uV, max_uV);
2631                         else if (rdev->desc->ops->list_voltage ==
2632                                  regulator_list_voltage_linear_range)
2633                                 ret = regulator_map_voltage_linear_range(rdev,
2634                                                                 min_uV, max_uV);
2635                         else
2636                                 ret = regulator_map_voltage_iterate(rdev,
2637                                                                 min_uV, max_uV);
2638                 }
2639
2640                 if (ret >= 0) {
2641                         best_val = rdev->desc->ops->list_voltage(rdev, ret);
2642                         if (min_uV <= best_val && max_uV >= best_val) {
2643                                 selector = ret;
2644                                 if (old_selector == selector)
2645                                         ret = 0;
2646                                 else
2647                                         ret = _regulator_call_set_voltage_sel(
2648                                                 rdev, best_val, selector);
2649                         } else {
2650                                 ret = -EINVAL;
2651                         }
2652                 }
2653         } else {
2654                 ret = -EINVAL;
2655         }
2656
2657         /* Call set_voltage_time_sel if successfully obtained old_selector */
2658         if (ret == 0 && !rdev->constraints->ramp_disable && old_selector >= 0
2659                 && old_selector != selector) {
2660
2661                 delay = rdev->desc->ops->set_voltage_time_sel(rdev,
2662                                                 old_selector, selector);
2663                 if (delay < 0) {
2664                         rdev_warn(rdev, "set_voltage_time_sel() failed: %d\n",
2665                                   delay);
2666                         delay = 0;
2667                 }
2668
2669                 /* Insert any necessary delays */
2670                 if (delay >= 1000) {
2671                         mdelay(delay / 1000);
2672                         udelay(delay % 1000);
2673                 } else if (delay) {
2674                         udelay(delay);
2675                 }
2676         }
2677
2678         if (ret == 0 && best_val >= 0) {
2679                 unsigned long data = best_val;
2680
2681                 _notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE,
2682                                      (void *)data);
2683         }
2684
2685         trace_regulator_set_voltage_complete(rdev_get_name(rdev), best_val);
2686
2687         return ret;
2688 }
2689
2690 /**
2691  * regulator_set_voltage - set regulator output voltage
2692  * @regulator: regulator source
2693  * @min_uV: Minimum required voltage in uV
2694  * @max_uV: Maximum acceptable voltage in uV
2695  *
2696  * Sets a voltage regulator to the desired output voltage. This can be set
2697  * during any regulator state. IOW, regulator can be disabled or enabled.
2698  *
2699  * If the regulator is enabled then the voltage will change to the new value
2700  * immediately otherwise if the regulator is disabled the regulator will
2701  * output at the new voltage when enabled.
2702  *
2703  * NOTE: If the regulator is shared between several devices then the lowest
2704  * request voltage that meets the system constraints will be used.
2705  * Regulator system constraints must be set for this regulator before
2706  * calling this function otherwise this call will fail.
2707  */
2708 int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
2709 {
2710         struct regulator_dev *rdev = regulator->rdev;
2711         int ret = 0;
2712         int old_min_uV, old_max_uV;
2713         int current_uV;
2714
2715         mutex_lock(&rdev->mutex);
2716
2717         /* If we're setting the same range as last time the change
2718          * should be a noop (some cpufreq implementations use the same
2719          * voltage for multiple frequencies, for example).
2720          */
2721         if (regulator->min_uV == min_uV && regulator->max_uV == max_uV)
2722                 goto out;
2723
2724         /* If we're trying to set a range that overlaps the current voltage,
2725          * return succesfully even though the regulator does not support
2726          * changing the voltage.
2727          */
2728         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
2729                 current_uV = _regulator_get_voltage(rdev);
2730                 if (min_uV <= current_uV && current_uV <= max_uV) {
2731                         regulator->min_uV = min_uV;
2732                         regulator->max_uV = max_uV;
2733                         goto out;
2734                 }
2735         }
2736
2737         /* sanity check */
2738         if (!rdev->desc->ops->set_voltage &&
2739             !rdev->desc->ops->set_voltage_sel) {
2740                 ret = -EINVAL;
2741                 goto out;
2742         }
2743
2744         /* constraints check */
2745         ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
2746         if (ret < 0)
2747                 goto out;
2748
2749         /* restore original values in case of error */
2750         old_min_uV = regulator->min_uV;
2751         old_max_uV = regulator->max_uV;
2752         regulator->min_uV = min_uV;
2753         regulator->max_uV = max_uV;
2754
2755         ret = regulator_check_consumers(rdev, &min_uV, &max_uV);
2756         if (ret < 0)
2757                 goto out2;
2758
2759         ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
2760         if (ret < 0)
2761                 goto out2;
2762
2763 out:
2764         mutex_unlock(&rdev->mutex);
2765         return ret;
2766 out2:
2767         regulator->min_uV = old_min_uV;
2768         regulator->max_uV = old_max_uV;
2769         mutex_unlock(&rdev->mutex);
2770         return ret;
2771 }
2772 EXPORT_SYMBOL_GPL(regulator_set_voltage);
2773
2774 /**
2775  * regulator_set_voltage_time - get raise/fall time
2776  * @regulator: regulator source
2777  * @old_uV: starting voltage in microvolts
2778  * @new_uV: target voltage in microvolts
2779  *
2780  * Provided with the starting and ending voltage, this function attempts to
2781  * calculate the time in microseconds required to rise or fall to this new
2782  * voltage.
2783  */
2784 int regulator_set_voltage_time(struct regulator *regulator,
2785                                int old_uV, int new_uV)
2786 {
2787         struct regulator_dev *rdev = regulator->rdev;
2788         const struct regulator_ops *ops = rdev->desc->ops;
2789         int old_sel = -1;
2790         int new_sel = -1;
2791         int voltage;
2792         int i;
2793
2794         /* Currently requires operations to do this */
2795         if (!ops->list_voltage || !ops->set_voltage_time_sel
2796             || !rdev->desc->n_voltages)
2797                 return -EINVAL;
2798
2799         for (i = 0; i < rdev->desc->n_voltages; i++) {
2800                 /* We only look for exact voltage matches here */
2801                 voltage = regulator_list_voltage(regulator, i);
2802                 if (voltage < 0)
2803                         return -EINVAL;
2804                 if (voltage == 0)
2805                         continue;
2806                 if (voltage == old_uV)
2807                         old_sel = i;
2808                 if (voltage == new_uV)
2809                         new_sel = i;
2810         }
2811
2812         if (old_sel < 0 || new_sel < 0)
2813                 return -EINVAL;
2814
2815         return ops->set_voltage_time_sel(rdev, old_sel, new_sel);
2816 }
2817 EXPORT_SYMBOL_GPL(regulator_set_voltage_time);
2818
2819 /**
2820  * regulator_set_voltage_time_sel - get raise/fall time
2821  * @rdev: regulator source device
2822  * @old_selector: selector for starting voltage
2823  * @new_selector: selector for target voltage
2824  *
2825  * Provided with the starting and target voltage selectors, this function
2826  * returns time in microseconds required to rise or fall to this new voltage
2827  *
2828  * Drivers providing ramp_delay in regulation_constraints can use this as their
2829  * set_voltage_time_sel() operation.
2830  */
2831 int regulator_set_voltage_time_sel(struct regulator_dev *rdev,
2832                                    unsigned int old_selector,
2833                                    unsigned int new_selector)
2834 {
2835         unsigned int ramp_delay = 0;
2836         int old_volt, new_volt;
2837
2838         if (rdev->constraints->ramp_delay)
2839                 ramp_delay = rdev->constraints->ramp_delay;
2840         else if (rdev->desc->ramp_delay)
2841                 ramp_delay = rdev->desc->ramp_delay;
2842
2843         if (ramp_delay == 0) {
2844                 rdev_warn(rdev, "ramp_delay not set\n");
2845                 return 0;
2846         }
2847
2848         /* sanity check */
2849         if (!rdev->desc->ops->list_voltage)
2850                 return -EINVAL;
2851
2852         old_volt = rdev->desc->ops->list_voltage(rdev, old_selector);
2853         new_volt = rdev->desc->ops->list_voltage(rdev, new_selector);
2854
2855         return DIV_ROUND_UP(abs(new_volt - old_volt), ramp_delay);
2856 }
2857 EXPORT_SYMBOL_GPL(regulator_set_voltage_time_sel);
2858
2859 /**
2860  * regulator_sync_voltage - re-apply last regulator output voltage
2861  * @regulator: regulator source
2862  *
2863  * Re-apply the last configured voltage.  This is intended to be used
2864  * where some external control source the consumer is cooperating with
2865  * has caused the configured voltage to change.
2866  */
2867 int regulator_sync_voltage(struct regulator *regulator)
2868 {
2869         struct regulator_dev *rdev = regulator->rdev;
2870         int ret, min_uV, max_uV;
2871
2872         mutex_lock(&rdev->mutex);
2873
2874         if (!rdev->desc->ops->set_voltage &&
2875             !rdev->desc->ops->set_voltage_sel) {
2876                 ret = -EINVAL;
2877                 goto out;
2878         }
2879
2880         /* This is only going to work if we've had a voltage configured. */
2881         if (!regulator->min_uV && !regulator->max_uV) {
2882                 ret = -EINVAL;
2883                 goto out;
2884         }
2885
2886         min_uV = regulator->min_uV;
2887         max_uV = regulator->max_uV;
2888
2889         /* This should be a paranoia check... */
2890         ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
2891         if (ret < 0)
2892                 goto out;
2893
2894         ret = regulator_check_consumers(rdev, &min_uV, &max_uV);
2895         if (ret < 0)
2896                 goto out;
2897
2898         ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
2899
2900 out:
2901         mutex_unlock(&rdev->mutex);
2902         return ret;
2903 }
2904 EXPORT_SYMBOL_GPL(regulator_sync_voltage);
2905
2906 static int _regulator_get_voltage(struct regulator_dev *rdev)
2907 {
2908         int sel, ret;
2909
2910         if (rdev->desc->ops->get_voltage_sel) {
2911                 sel = rdev->desc->ops->get_voltage_sel(rdev);
2912                 if (sel < 0)
2913                         return sel;
2914                 ret = rdev->desc->ops->list_voltage(rdev, sel);
2915         } else if (rdev->desc->ops->get_voltage) {
2916                 ret = rdev->desc->ops->get_voltage(rdev);
2917         } else if (rdev->desc->ops->list_voltage) {
2918                 ret = rdev->desc->ops->list_voltage(rdev, 0);
2919         } else if (rdev->desc->fixed_uV && (rdev->desc->n_voltages == 1)) {
2920                 ret = rdev->desc->fixed_uV;
2921         } else if (rdev->supply) {
2922                 ret = regulator_get_voltage(rdev->supply);
2923         } else {
2924                 return -EINVAL;
2925         }
2926
2927         if (ret < 0)
2928                 return ret;
2929         return ret - rdev->constraints->uV_offset;
2930 }
2931
2932 /**
2933  * regulator_get_voltage - get regulator output voltage
2934  * @regulator: regulator source
2935  *
2936  * This returns the current regulator voltage in uV.
2937  *
2938  * NOTE: If the regulator is disabled it will return the voltage value. This
2939  * function should not be used to determine regulator state.
2940  */
2941 int regulator_get_voltage(struct regulator *regulator)
2942 {
2943         int ret;
2944
2945         mutex_lock(&regulator->rdev->mutex);
2946
2947         ret = _regulator_get_voltage(regulator->rdev);
2948
2949         mutex_unlock(&regulator->rdev->mutex);
2950
2951         return ret;
2952 }
2953 EXPORT_SYMBOL_GPL(regulator_get_voltage);
2954
2955 /**
2956  * regulator_set_current_limit - set regulator output current limit
2957  * @regulator: regulator source
2958  * @min_uA: Minimum supported current in uA
2959  * @max_uA: Maximum supported current in uA
2960  *
2961  * Sets current sink to the desired output current. This can be set during
2962  * any regulator state. IOW, regulator can be disabled or enabled.
2963  *
2964  * If the regulator is enabled then the current will change to the new value
2965  * immediately otherwise if the regulator is disabled the regulator will
2966  * output at the new current when enabled.
2967  *
2968  * NOTE: Regulator system constraints must be set for this regulator before
2969  * calling this function otherwise this call will fail.
2970  */
2971 int regulator_set_current_limit(struct regulator *regulator,
2972                                int min_uA, int max_uA)
2973 {
2974         struct regulator_dev *rdev = regulator->rdev;
2975         int ret;
2976
2977         mutex_lock(&rdev->mutex);
2978
2979         /* sanity check */
2980         if (!rdev->desc->ops->set_current_limit) {
2981                 ret = -EINVAL;
2982                 goto out;
2983         }
2984
2985         /* constraints check */
2986         ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
2987         if (ret < 0)
2988                 goto out;
2989
2990         ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
2991 out:
2992         mutex_unlock(&rdev->mutex);
2993         return ret;
2994 }
2995 EXPORT_SYMBOL_GPL(regulator_set_current_limit);
2996
2997 static int _regulator_get_current_limit(struct regulator_dev *rdev)
2998 {
2999         int ret;
3000
3001         mutex_lock(&rdev->mutex);
3002
3003         /* sanity check */
3004         if (!rdev->desc->ops->get_current_limit) {
3005                 ret = -EINVAL;
3006                 goto out;
3007         }
3008
3009         ret = rdev->desc->ops->get_current_limit(rdev);
3010 out:
3011         mutex_unlock(&rdev->mutex);
3012         return ret;
3013 }
3014
3015 /**
3016  * regulator_get_current_limit - get regulator output current
3017  * @regulator: regulator source
3018  *
3019  * This returns the current supplied by the specified current sink in uA.
3020  *
3021  * NOTE: If the regulator is disabled it will return the current value. This
3022  * function should not be used to determine regulator state.
3023  */
3024 int regulator_get_current_limit(struct regulator *regulator)
3025 {
3026         return _regulator_get_current_limit(regulator->rdev);
3027 }
3028 EXPORT_SYMBOL_GPL(regulator_get_current_limit);
3029
3030 /**
3031  * regulator_set_mode - set regulator operating mode
3032  * @regulator: regulator source
3033  * @mode: operating mode - one of the REGULATOR_MODE constants
3034  *
3035  * Set regulator operating mode to increase regulator efficiency or improve
3036  * regulation performance.
3037  *
3038  * NOTE: Regulator system constraints must be set for this regulator before
3039  * calling this function otherwise this call will fail.
3040  */
3041 int regulator_set_mode(struct regulator *regulator, unsigned int mode)
3042 {
3043         struct regulator_dev *rdev = regulator->rdev;
3044         int ret;
3045         int regulator_curr_mode;
3046
3047         mutex_lock(&rdev->mutex);
3048
3049         /* sanity check */
3050         if (!rdev->desc->ops->set_mode) {
3051                 ret = -EINVAL;
3052                 goto out;
3053         }
3054
3055         /* return if the same mode is requested */
3056         if (rdev->desc->ops->get_mode) {
3057                 regulator_curr_mode = rdev->desc->ops->get_mode(rdev);
3058                 if (regulator_curr_mode == mode) {
3059                         ret = 0;
3060                         goto out;
3061                 }
3062         }
3063
3064         /* constraints check */
3065         ret = regulator_mode_constrain(rdev, &mode);
3066         if (ret < 0)
3067                 goto out;
3068
3069         ret = rdev->desc->ops->set_mode(rdev, mode);
3070 out:
3071         mutex_unlock(&rdev->mutex);
3072         return ret;
3073 }
3074 EXPORT_SYMBOL_GPL(regulator_set_mode);
3075
3076 static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
3077 {
3078         int ret;
3079
3080         mutex_lock(&rdev->mutex);
3081
3082         /* sanity check */
3083         if (!rdev->desc->ops->get_mode) {
3084                 ret = -EINVAL;
3085                 goto out;
3086         }
3087
3088         ret = rdev->desc->ops->get_mode(rdev);
3089 out:
3090         mutex_unlock(&rdev->mutex);
3091         return ret;
3092 }
3093
3094 /**
3095  * regulator_get_mode - get regulator operating mode
3096  * @regulator: regulator source
3097  *
3098  * Get the current regulator operating mode.
3099  */
3100 unsigned int regulator_get_mode(struct regulator *regulator)
3101 {
3102         return _regulator_get_mode(regulator->rdev);
3103 }
3104 EXPORT_SYMBOL_GPL(regulator_get_mode);
3105
3106 /**
3107  * regulator_set_load - set regulator load
3108  * @regulator: regulator source
3109  * @uA_load: load current
3110  *
3111  * Notifies the regulator core of a new device load. This is then used by
3112  * DRMS (if enabled by constraints) to set the most efficient regulator
3113  * operating mode for the new regulator loading.
3114  *
3115  * Consumer devices notify their supply regulator of the maximum power
3116  * they will require (can be taken from device datasheet in the power
3117  * consumption tables) when they change operational status and hence power
3118  * state. Examples of operational state changes that can affect power
3119  * consumption are :-
3120  *
3121  *    o Device is opened / closed.
3122  *    o Device I/O is about to begin or has just finished.
3123  *    o Device is idling in between work.
3124  *
3125  * This information is also exported via sysfs to userspace.
3126  *
3127  * DRMS will sum the total requested load on the regulator and change
3128  * to the most efficient operating mode if platform constraints allow.
3129  *
3130  * On error a negative errno is returned.
3131  */
3132 int regulator_set_load(struct regulator *regulator, int uA_load)
3133 {
3134         struct regulator_dev *rdev = regulator->rdev;
3135         int ret;
3136
3137         mutex_lock(&rdev->mutex);
3138         regulator->uA_load = uA_load;
3139         ret = drms_uA_update(rdev);
3140         mutex_unlock(&rdev->mutex);
3141
3142         return ret;
3143 }
3144 EXPORT_SYMBOL_GPL(regulator_set_load);
3145
3146 /**
3147  * regulator_allow_bypass - allow the regulator to go into bypass mode
3148  *
3149  * @regulator: Regulator to configure
3150  * @enable: enable or disable bypass mode
3151  *
3152  * Allow the regulator to go into bypass mode if all other consumers
3153  * for the regulator also enable bypass mode and the machine
3154  * constraints allow this.  Bypass mode means that the regulator is
3155  * simply passing the input directly to the output with no regulation.
3156  */
3157 int regulator_allow_bypass(struct regulator *regulator, bool enable)
3158 {
3159         struct regulator_dev *rdev = regulator->rdev;
3160         int ret = 0;
3161
3162         if (!rdev->desc->ops->set_bypass)
3163                 return 0;
3164
3165         if (rdev->constraints &&
3166             !(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_BYPASS))
3167                 return 0;
3168
3169         mutex_lock(&rdev->mutex);
3170
3171         if (enable && !regulator->bypass) {
3172                 rdev->bypass_count++;
3173
3174                 if (rdev->bypass_count == rdev->open_count) {
3175                         ret = rdev->desc->ops->set_bypass(rdev, enable);
3176                         if (ret != 0)
3177                                 rdev->bypass_count--;
3178                 }
3179
3180         } else if (!enable && regulator->bypass) {
3181                 rdev->bypass_count--;
3182
3183                 if (rdev->bypass_count != rdev->open_count) {
3184                         ret = rdev->desc->ops->set_bypass(rdev, enable);
3185                         if (ret != 0)
3186                                 rdev->bypass_count++;
3187                 }
3188         }
3189
3190         if (ret == 0)
3191                 regulator->bypass = enable;
3192
3193         mutex_unlock(&rdev->mutex);
3194
3195         return ret;
3196 }
3197 EXPORT_SYMBOL_GPL(regulator_allow_bypass);
3198
3199 /**
3200  * regulator_register_notifier - register regulator event notifier
3201  * @regulator: regulator source
3202  * @nb: notifier block
3203  *
3204  * Register notifier block to receive regulator events.
3205  */
3206 int regulator_register_notifier(struct regulator *regulator,
3207                               struct notifier_block *nb)
3208 {
3209         return blocking_notifier_chain_register(&regulator->rdev->notifier,
3210                                                 nb);
3211 }
3212 EXPORT_SYMBOL_GPL(regulator_register_notifier);
3213
3214 /**
3215  * regulator_unregister_notifier - unregister regulator event notifier
3216  * @regulator: regulator source
3217  * @nb: notifier block
3218  *
3219  * Unregister regulator event notifier block.
3220  */
3221 int regulator_unregister_notifier(struct regulator *regulator,
3222                                 struct notifier_block *nb)
3223 {
3224         return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
3225                                                   nb);
3226 }
3227 EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
3228
3229 /* notify regulator consumers and downstream regulator consumers.
3230  * Note mutex must be held by caller.
3231  */
3232 static int _notifier_call_chain(struct regulator_dev *rdev,
3233                                   unsigned long event, void *data)
3234 {
3235         /* call rdev chain first */
3236         return blocking_notifier_call_chain(&rdev->notifier, event, data);
3237 }
3238
3239 /**
3240  * regulator_bulk_get - get multiple regulator consumers
3241  *
3242  * @dev:           Device to supply
3243  * @num_consumers: Number of consumers to register
3244  * @consumers:     Configuration of consumers; clients are stored here.
3245  *
3246  * @return 0 on success, an errno on failure.
3247  *
3248  * This helper function allows drivers to get several regulator
3249  * consumers in one operation.  If any of the regulators cannot be
3250  * acquired then any regulators that were allocated will be freed
3251  * before returning to the caller.
3252  */
3253 int regulator_bulk_get(struct device *dev, int num_consumers,
3254                        struct regulator_bulk_data *consumers)
3255 {
3256         int i;
3257         int ret;
3258
3259         for (i = 0; i < num_consumers; i++)
3260                 consumers[i].consumer = NULL;
3261
3262         for (i = 0; i < num_consumers; i++) {
3263                 consumers[i].consumer = regulator_get(dev,
3264                                                       consumers[i].supply);
3265                 if (IS_ERR(consumers[i].consumer)) {
3266                         ret = PTR_ERR(consumers[i].consumer);
3267                         dev_err(dev, "Failed to get supply '%s': %d\n",
3268                                 consumers[i].supply, ret);
3269                         consumers[i].consumer = NULL;
3270                         goto err;
3271                 }
3272         }
3273
3274         return 0;
3275
3276 err:
3277         while (--i >= 0)
3278                 regulator_put(consumers[i].consumer);
3279
3280         return ret;
3281 }
3282 EXPORT_SYMBOL_GPL(regulator_bulk_get);
3283
3284 static void regulator_bulk_enable_async(void *data, async_cookie_t cookie)
3285 {
3286         struct regulator_bulk_data *bulk = data;
3287
3288         bulk->ret = regulator_enable(bulk->consumer);
3289 }
3290
3291 /**
3292  * regulator_bulk_enable - enable multiple regulator consumers
3293  *
3294  * @num_consumers: Number of consumers
3295  * @consumers:     Consumer data; clients are stored here.
3296  * @return         0 on success, an&nb