xref: /openbmc/linux/drivers/regulator/core.c (revision 78bb17f7)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 //
3 // core.c  --  Voltage/Current Regulator framework.
4 //
5 // Copyright 2007, 2008 Wolfson Microelectronics PLC.
6 // Copyright 2008 SlimLogic Ltd.
7 //
8 // Author: Liam Girdwood <lrg@slimlogic.co.uk>
9 
10 #include <linux/kernel.h>
11 #include <linux/init.h>
12 #include <linux/debugfs.h>
13 #include <linux/device.h>
14 #include <linux/slab.h>
15 #include <linux/async.h>
16 #include <linux/err.h>
17 #include <linux/mutex.h>
18 #include <linux/suspend.h>
19 #include <linux/delay.h>
20 #include <linux/gpio/consumer.h>
21 #include <linux/of.h>
22 #include <linux/regmap.h>
23 #include <linux/regulator/of_regulator.h>
24 #include <linux/regulator/consumer.h>
25 #include <linux/regulator/coupler.h>
26 #include <linux/regulator/driver.h>
27 #include <linux/regulator/machine.h>
28 #include <linux/module.h>
29 
30 #define CREATE_TRACE_POINTS
31 #include <trace/events/regulator.h>
32 
33 #include "dummy.h"
34 #include "internal.h"
35 
36 #define rdev_crit(rdev, fmt, ...)					\
37 	pr_crit("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
38 #define rdev_err(rdev, fmt, ...)					\
39 	pr_err("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
40 #define rdev_warn(rdev, fmt, ...)					\
41 	pr_warn("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
42 #define rdev_info(rdev, fmt, ...)					\
43 	pr_info("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
44 #define rdev_dbg(rdev, fmt, ...)					\
45 	pr_debug("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
46 
47 static DEFINE_WW_CLASS(regulator_ww_class);
48 static DEFINE_MUTEX(regulator_nesting_mutex);
49 static DEFINE_MUTEX(regulator_list_mutex);
50 static LIST_HEAD(regulator_map_list);
51 static LIST_HEAD(regulator_ena_gpio_list);
52 static LIST_HEAD(regulator_supply_alias_list);
53 static LIST_HEAD(regulator_coupler_list);
54 static bool has_full_constraints;
55 
56 static struct dentry *debugfs_root;
57 
58 /*
59  * struct regulator_map
60  *
61  * Used to provide symbolic supply names to devices.
62  */
63 struct regulator_map {
64 	struct list_head list;
65 	const char *dev_name;   /* The dev_name() for the consumer */
66 	const char *supply;
67 	struct regulator_dev *regulator;
68 };
69 
70 /*
71  * struct regulator_enable_gpio
72  *
73  * Management for shared enable GPIO pin
74  */
75 struct regulator_enable_gpio {
76 	struct list_head list;
77 	struct gpio_desc *gpiod;
78 	u32 enable_count;	/* a number of enabled shared GPIO */
79 	u32 request_count;	/* a number of requested shared GPIO */
80 };
81 
82 /*
83  * struct regulator_supply_alias
84  *
85  * Used to map lookups for a supply onto an alternative device.
86  */
87 struct regulator_supply_alias {
88 	struct list_head list;
89 	struct device *src_dev;
90 	const char *src_supply;
91 	struct device *alias_dev;
92 	const char *alias_supply;
93 };
94 
95 static int _regulator_is_enabled(struct regulator_dev *rdev);
96 static int _regulator_disable(struct regulator *regulator);
97 static int _regulator_get_current_limit(struct regulator_dev *rdev);
98 static unsigned int _regulator_get_mode(struct regulator_dev *rdev);
99 static int _notifier_call_chain(struct regulator_dev *rdev,
100 				  unsigned long event, void *data);
101 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
102 				     int min_uV, int max_uV);
103 static int regulator_balance_voltage(struct regulator_dev *rdev,
104 				     suspend_state_t state);
105 static struct regulator *create_regulator(struct regulator_dev *rdev,
106 					  struct device *dev,
107 					  const char *supply_name);
108 static void _regulator_put(struct regulator *regulator);
109 
110 const char *rdev_get_name(struct regulator_dev *rdev)
111 {
112 	if (rdev->constraints && rdev->constraints->name)
113 		return rdev->constraints->name;
114 	else if (rdev->desc->name)
115 		return rdev->desc->name;
116 	else
117 		return "";
118 }
119 
120 static bool have_full_constraints(void)
121 {
122 	return has_full_constraints || of_have_populated_dt();
123 }
124 
125 static bool regulator_ops_is_valid(struct regulator_dev *rdev, int ops)
126 {
127 	if (!rdev->constraints) {
128 		rdev_err(rdev, "no constraints\n");
129 		return false;
130 	}
131 
132 	if (rdev->constraints->valid_ops_mask & ops)
133 		return true;
134 
135 	return false;
136 }
137 
138 /**
139  * regulator_lock_nested - lock a single regulator
140  * @rdev:		regulator source
141  * @ww_ctx:		w/w mutex acquire context
142  *
143  * This function can be called many times by one task on
144  * a single regulator and its mutex will be locked only
145  * once. If a task, which is calling this function is other
146  * than the one, which initially locked the mutex, it will
147  * wait on mutex.
148  */
149 static inline int regulator_lock_nested(struct regulator_dev *rdev,
150 					struct ww_acquire_ctx *ww_ctx)
151 {
152 	bool lock = false;
153 	int ret = 0;
154 
155 	mutex_lock(&regulator_nesting_mutex);
156 
157 	if (ww_ctx || !ww_mutex_trylock(&rdev->mutex)) {
158 		if (rdev->mutex_owner == current)
159 			rdev->ref_cnt++;
160 		else
161 			lock = true;
162 
163 		if (lock) {
164 			mutex_unlock(&regulator_nesting_mutex);
165 			ret = ww_mutex_lock(&rdev->mutex, ww_ctx);
166 			mutex_lock(&regulator_nesting_mutex);
167 		}
168 	} else {
169 		lock = true;
170 	}
171 
172 	if (lock && ret != -EDEADLK) {
173 		rdev->ref_cnt++;
174 		rdev->mutex_owner = current;
175 	}
176 
177 	mutex_unlock(&regulator_nesting_mutex);
178 
179 	return ret;
180 }
181 
182 /**
183  * regulator_lock - lock a single regulator
184  * @rdev:		regulator source
185  *
186  * This function can be called many times by one task on
187  * a single regulator and its mutex will be locked only
188  * once. If a task, which is calling this function is other
189  * than the one, which initially locked the mutex, it will
190  * wait on mutex.
191  */
192 void regulator_lock(struct regulator_dev *rdev)
193 {
194 	regulator_lock_nested(rdev, NULL);
195 }
196 EXPORT_SYMBOL_GPL(regulator_lock);
197 
198 /**
199  * regulator_unlock - unlock a single regulator
200  * @rdev:		regulator_source
201  *
202  * This function unlocks the mutex when the
203  * reference counter reaches 0.
204  */
205 void regulator_unlock(struct regulator_dev *rdev)
206 {
207 	mutex_lock(&regulator_nesting_mutex);
208 
209 	if (--rdev->ref_cnt == 0) {
210 		rdev->mutex_owner = NULL;
211 		ww_mutex_unlock(&rdev->mutex);
212 	}
213 
214 	WARN_ON_ONCE(rdev->ref_cnt < 0);
215 
216 	mutex_unlock(&regulator_nesting_mutex);
217 }
218 EXPORT_SYMBOL_GPL(regulator_unlock);
219 
220 static bool regulator_supply_is_couple(struct regulator_dev *rdev)
221 {
222 	struct regulator_dev *c_rdev;
223 	int i;
224 
225 	for (i = 1; i < rdev->coupling_desc.n_coupled; i++) {
226 		c_rdev = rdev->coupling_desc.coupled_rdevs[i];
227 
228 		if (rdev->supply->rdev == c_rdev)
229 			return true;
230 	}
231 
232 	return false;
233 }
234 
235 static void regulator_unlock_recursive(struct regulator_dev *rdev,
236 				       unsigned int n_coupled)
237 {
238 	struct regulator_dev *c_rdev;
239 	int i;
240 
241 	for (i = n_coupled; i > 0; i--) {
242 		c_rdev = rdev->coupling_desc.coupled_rdevs[i - 1];
243 
244 		if (!c_rdev)
245 			continue;
246 
247 		if (c_rdev->supply && !regulator_supply_is_couple(c_rdev))
248 			regulator_unlock_recursive(
249 					c_rdev->supply->rdev,
250 					c_rdev->coupling_desc.n_coupled);
251 
252 		regulator_unlock(c_rdev);
253 	}
254 }
255 
256 static int regulator_lock_recursive(struct regulator_dev *rdev,
257 				    struct regulator_dev **new_contended_rdev,
258 				    struct regulator_dev **old_contended_rdev,
259 				    struct ww_acquire_ctx *ww_ctx)
260 {
261 	struct regulator_dev *c_rdev;
262 	int i, err;
263 
264 	for (i = 0; i < rdev->coupling_desc.n_coupled; i++) {
265 		c_rdev = rdev->coupling_desc.coupled_rdevs[i];
266 
267 		if (!c_rdev)
268 			continue;
269 
270 		if (c_rdev != *old_contended_rdev) {
271 			err = regulator_lock_nested(c_rdev, ww_ctx);
272 			if (err) {
273 				if (err == -EDEADLK) {
274 					*new_contended_rdev = c_rdev;
275 					goto err_unlock;
276 				}
277 
278 				/* shouldn't happen */
279 				WARN_ON_ONCE(err != -EALREADY);
280 			}
281 		} else {
282 			*old_contended_rdev = NULL;
283 		}
284 
285 		if (c_rdev->supply && !regulator_supply_is_couple(c_rdev)) {
286 			err = regulator_lock_recursive(c_rdev->supply->rdev,
287 						       new_contended_rdev,
288 						       old_contended_rdev,
289 						       ww_ctx);
290 			if (err) {
291 				regulator_unlock(c_rdev);
292 				goto err_unlock;
293 			}
294 		}
295 	}
296 
297 	return 0;
298 
299 err_unlock:
300 	regulator_unlock_recursive(rdev, i);
301 
302 	return err;
303 }
304 
305 /**
306  * regulator_unlock_dependent - unlock regulator's suppliers and coupled
307  *				regulators
308  * @rdev:			regulator source
309  * @ww_ctx:			w/w mutex acquire context
310  *
311  * Unlock all regulators related with rdev by coupling or supplying.
312  */
313 static void regulator_unlock_dependent(struct regulator_dev *rdev,
314 				       struct ww_acquire_ctx *ww_ctx)
315 {
316 	regulator_unlock_recursive(rdev, rdev->coupling_desc.n_coupled);
317 	ww_acquire_fini(ww_ctx);
318 }
319 
320 /**
321  * regulator_lock_dependent - lock regulator's suppliers and coupled regulators
322  * @rdev:			regulator source
323  * @ww_ctx:			w/w mutex acquire context
324  *
325  * This function as a wrapper on regulator_lock_recursive(), which locks
326  * all regulators related with rdev by coupling or supplying.
327  */
328 static void regulator_lock_dependent(struct regulator_dev *rdev,
329 				     struct ww_acquire_ctx *ww_ctx)
330 {
331 	struct regulator_dev *new_contended_rdev = NULL;
332 	struct regulator_dev *old_contended_rdev = NULL;
333 	int err;
334 
335 	mutex_lock(&regulator_list_mutex);
336 
337 	ww_acquire_init(ww_ctx, &regulator_ww_class);
338 
339 	do {
340 		if (new_contended_rdev) {
341 			ww_mutex_lock_slow(&new_contended_rdev->mutex, ww_ctx);
342 			old_contended_rdev = new_contended_rdev;
343 			old_contended_rdev->ref_cnt++;
344 		}
345 
346 		err = regulator_lock_recursive(rdev,
347 					       &new_contended_rdev,
348 					       &old_contended_rdev,
349 					       ww_ctx);
350 
351 		if (old_contended_rdev)
352 			regulator_unlock(old_contended_rdev);
353 
354 	} while (err == -EDEADLK);
355 
356 	ww_acquire_done(ww_ctx);
357 
358 	mutex_unlock(&regulator_list_mutex);
359 }
360 
361 /**
362  * of_get_child_regulator - get a child regulator device node
363  * based on supply name
364  * @parent: Parent device node
365  * @prop_name: Combination regulator supply name and "-supply"
366  *
367  * Traverse all child nodes.
368  * Extract the child regulator device node corresponding to the supply name.
369  * returns the device node corresponding to the regulator if found, else
370  * returns NULL.
371  */
372 static struct device_node *of_get_child_regulator(struct device_node *parent,
373 						  const char *prop_name)
374 {
375 	struct device_node *regnode = NULL;
376 	struct device_node *child = NULL;
377 
378 	for_each_child_of_node(parent, child) {
379 		regnode = of_parse_phandle(child, prop_name, 0);
380 
381 		if (!regnode) {
382 			regnode = of_get_child_regulator(child, prop_name);
383 			if (regnode)
384 				goto err_node_put;
385 		} else {
386 			goto err_node_put;
387 		}
388 	}
389 	return NULL;
390 
391 err_node_put:
392 	of_node_put(child);
393 	return regnode;
394 }
395 
396 /**
397  * of_get_regulator - get a regulator device node based on supply name
398  * @dev: Device pointer for the consumer (of regulator) device
399  * @supply: regulator supply name
400  *
401  * Extract the regulator device node corresponding to the supply name.
402  * returns the device node corresponding to the regulator if found, else
403  * returns NULL.
404  */
405 static struct device_node *of_get_regulator(struct device *dev, const char *supply)
406 {
407 	struct device_node *regnode = NULL;
408 	char prop_name[32]; /* 32 is max size of property name */
409 
410 	dev_dbg(dev, "Looking up %s-supply from device tree\n", supply);
411 
412 	snprintf(prop_name, 32, "%s-supply", supply);
413 	regnode = of_parse_phandle(dev->of_node, prop_name, 0);
414 
415 	if (!regnode) {
416 		regnode = of_get_child_regulator(dev->of_node, prop_name);
417 		if (regnode)
418 			return regnode;
419 
420 		dev_dbg(dev, "Looking up %s property in node %pOF failed\n",
421 				prop_name, dev->of_node);
422 		return NULL;
423 	}
424 	return regnode;
425 }
426 
427 /* Platform voltage constraint check */
428 int regulator_check_voltage(struct regulator_dev *rdev,
429 			    int *min_uV, int *max_uV)
430 {
431 	BUG_ON(*min_uV > *max_uV);
432 
433 	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE)) {
434 		rdev_err(rdev, "voltage operation not allowed\n");
435 		return -EPERM;
436 	}
437 
438 	if (*max_uV > rdev->constraints->max_uV)
439 		*max_uV = rdev->constraints->max_uV;
440 	if (*min_uV < rdev->constraints->min_uV)
441 		*min_uV = rdev->constraints->min_uV;
442 
443 	if (*min_uV > *max_uV) {
444 		rdev_err(rdev, "unsupportable voltage range: %d-%duV\n",
445 			 *min_uV, *max_uV);
446 		return -EINVAL;
447 	}
448 
449 	return 0;
450 }
451 
452 /* return 0 if the state is valid */
453 static int regulator_check_states(suspend_state_t state)
454 {
455 	return (state > PM_SUSPEND_MAX || state == PM_SUSPEND_TO_IDLE);
456 }
457 
458 /* Make sure we select a voltage that suits the needs of all
459  * regulator consumers
460  */
461 int regulator_check_consumers(struct regulator_dev *rdev,
462 			      int *min_uV, int *max_uV,
463 			      suspend_state_t state)
464 {
465 	struct regulator *regulator;
466 	struct regulator_voltage *voltage;
467 
468 	list_for_each_entry(regulator, &rdev->consumer_list, list) {
469 		voltage = &regulator->voltage[state];
470 		/*
471 		 * Assume consumers that didn't say anything are OK
472 		 * with anything in the constraint range.
473 		 */
474 		if (!voltage->min_uV && !voltage->max_uV)
475 			continue;
476 
477 		if (*max_uV > voltage->max_uV)
478 			*max_uV = voltage->max_uV;
479 		if (*min_uV < voltage->min_uV)
480 			*min_uV = voltage->min_uV;
481 	}
482 
483 	if (*min_uV > *max_uV) {
484 		rdev_err(rdev, "Restricting voltage, %u-%uuV\n",
485 			*min_uV, *max_uV);
486 		return -EINVAL;
487 	}
488 
489 	return 0;
490 }
491 
492 /* current constraint check */
493 static int regulator_check_current_limit(struct regulator_dev *rdev,
494 					int *min_uA, int *max_uA)
495 {
496 	BUG_ON(*min_uA > *max_uA);
497 
498 	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_CURRENT)) {
499 		rdev_err(rdev, "current operation not allowed\n");
500 		return -EPERM;
501 	}
502 
503 	if (*max_uA > rdev->constraints->max_uA)
504 		*max_uA = rdev->constraints->max_uA;
505 	if (*min_uA < rdev->constraints->min_uA)
506 		*min_uA = rdev->constraints->min_uA;
507 
508 	if (*min_uA > *max_uA) {
509 		rdev_err(rdev, "unsupportable current range: %d-%duA\n",
510 			 *min_uA, *max_uA);
511 		return -EINVAL;
512 	}
513 
514 	return 0;
515 }
516 
517 /* operating mode constraint check */
518 static int regulator_mode_constrain(struct regulator_dev *rdev,
519 				    unsigned int *mode)
520 {
521 	switch (*mode) {
522 	case REGULATOR_MODE_FAST:
523 	case REGULATOR_MODE_NORMAL:
524 	case REGULATOR_MODE_IDLE:
525 	case REGULATOR_MODE_STANDBY:
526 		break;
527 	default:
528 		rdev_err(rdev, "invalid mode %x specified\n", *mode);
529 		return -EINVAL;
530 	}
531 
532 	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_MODE)) {
533 		rdev_err(rdev, "mode operation not allowed\n");
534 		return -EPERM;
535 	}
536 
537 	/* The modes are bitmasks, the most power hungry modes having
538 	 * the lowest values. If the requested mode isn't supported
539 	 * try higher modes. */
540 	while (*mode) {
541 		if (rdev->constraints->valid_modes_mask & *mode)
542 			return 0;
543 		*mode /= 2;
544 	}
545 
546 	return -EINVAL;
547 }
548 
549 static inline struct regulator_state *
550 regulator_get_suspend_state(struct regulator_dev *rdev, suspend_state_t state)
551 {
552 	if (rdev->constraints == NULL)
553 		return NULL;
554 
555 	switch (state) {
556 	case PM_SUSPEND_STANDBY:
557 		return &rdev->constraints->state_standby;
558 	case PM_SUSPEND_MEM:
559 		return &rdev->constraints->state_mem;
560 	case PM_SUSPEND_MAX:
561 		return &rdev->constraints->state_disk;
562 	default:
563 		return NULL;
564 	}
565 }
566 
567 static ssize_t regulator_uV_show(struct device *dev,
568 				struct device_attribute *attr, char *buf)
569 {
570 	struct regulator_dev *rdev = dev_get_drvdata(dev);
571 	int uV;
572 
573 	regulator_lock(rdev);
574 	uV = regulator_get_voltage_rdev(rdev);
575 	regulator_unlock(rdev);
576 
577 	if (uV < 0)
578 		return uV;
579 	return sprintf(buf, "%d\n", uV);
580 }
581 static DEVICE_ATTR(microvolts, 0444, regulator_uV_show, NULL);
582 
583 static ssize_t regulator_uA_show(struct device *dev,
584 				struct device_attribute *attr, char *buf)
585 {
586 	struct regulator_dev *rdev = dev_get_drvdata(dev);
587 
588 	return sprintf(buf, "%d\n", _regulator_get_current_limit(rdev));
589 }
590 static DEVICE_ATTR(microamps, 0444, regulator_uA_show, NULL);
591 
592 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
593 			 char *buf)
594 {
595 	struct regulator_dev *rdev = dev_get_drvdata(dev);
596 
597 	return sprintf(buf, "%s\n", rdev_get_name(rdev));
598 }
599 static DEVICE_ATTR_RO(name);
600 
601 static const char *regulator_opmode_to_str(int mode)
602 {
603 	switch (mode) {
604 	case REGULATOR_MODE_FAST:
605 		return "fast";
606 	case REGULATOR_MODE_NORMAL:
607 		return "normal";
608 	case REGULATOR_MODE_IDLE:
609 		return "idle";
610 	case REGULATOR_MODE_STANDBY:
611 		return "standby";
612 	}
613 	return "unknown";
614 }
615 
616 static ssize_t regulator_print_opmode(char *buf, int mode)
617 {
618 	return sprintf(buf, "%s\n", regulator_opmode_to_str(mode));
619 }
620 
621 static ssize_t regulator_opmode_show(struct device *dev,
622 				    struct device_attribute *attr, char *buf)
623 {
624 	struct regulator_dev *rdev = dev_get_drvdata(dev);
625 
626 	return regulator_print_opmode(buf, _regulator_get_mode(rdev));
627 }
628 static DEVICE_ATTR(opmode, 0444, regulator_opmode_show, NULL);
629 
630 static ssize_t regulator_print_state(char *buf, int state)
631 {
632 	if (state > 0)
633 		return sprintf(buf, "enabled\n");
634 	else if (state == 0)
635 		return sprintf(buf, "disabled\n");
636 	else
637 		return sprintf(buf, "unknown\n");
638 }
639 
640 static ssize_t regulator_state_show(struct device *dev,
641 				   struct device_attribute *attr, char *buf)
642 {
643 	struct regulator_dev *rdev = dev_get_drvdata(dev);
644 	ssize_t ret;
645 
646 	regulator_lock(rdev);
647 	ret = regulator_print_state(buf, _regulator_is_enabled(rdev));
648 	regulator_unlock(rdev);
649 
650 	return ret;
651 }
652 static DEVICE_ATTR(state, 0444, regulator_state_show, NULL);
653 
654 static ssize_t regulator_status_show(struct device *dev,
655 				   struct device_attribute *attr, char *buf)
656 {
657 	struct regulator_dev *rdev = dev_get_drvdata(dev);
658 	int status;
659 	char *label;
660 
661 	status = rdev->desc->ops->get_status(rdev);
662 	if (status < 0)
663 		return status;
664 
665 	switch (status) {
666 	case REGULATOR_STATUS_OFF:
667 		label = "off";
668 		break;
669 	case REGULATOR_STATUS_ON:
670 		label = "on";
671 		break;
672 	case REGULATOR_STATUS_ERROR:
673 		label = "error";
674 		break;
675 	case REGULATOR_STATUS_FAST:
676 		label = "fast";
677 		break;
678 	case REGULATOR_STATUS_NORMAL:
679 		label = "normal";
680 		break;
681 	case REGULATOR_STATUS_IDLE:
682 		label = "idle";
683 		break;
684 	case REGULATOR_STATUS_STANDBY:
685 		label = "standby";
686 		break;
687 	case REGULATOR_STATUS_BYPASS:
688 		label = "bypass";
689 		break;
690 	case REGULATOR_STATUS_UNDEFINED:
691 		label = "undefined";
692 		break;
693 	default:
694 		return -ERANGE;
695 	}
696 
697 	return sprintf(buf, "%s\n", label);
698 }
699 static DEVICE_ATTR(status, 0444, regulator_status_show, NULL);
700 
701 static ssize_t regulator_min_uA_show(struct device *dev,
702 				    struct device_attribute *attr, char *buf)
703 {
704 	struct regulator_dev *rdev = dev_get_drvdata(dev);
705 
706 	if (!rdev->constraints)
707 		return sprintf(buf, "constraint not defined\n");
708 
709 	return sprintf(buf, "%d\n", rdev->constraints->min_uA);
710 }
711 static DEVICE_ATTR(min_microamps, 0444, regulator_min_uA_show, NULL);
712 
713 static ssize_t regulator_max_uA_show(struct device *dev,
714 				    struct device_attribute *attr, char *buf)
715 {
716 	struct regulator_dev *rdev = dev_get_drvdata(dev);
717 
718 	if (!rdev->constraints)
719 		return sprintf(buf, "constraint not defined\n");
720 
721 	return sprintf(buf, "%d\n", rdev->constraints->max_uA);
722 }
723 static DEVICE_ATTR(max_microamps, 0444, regulator_max_uA_show, NULL);
724 
725 static ssize_t regulator_min_uV_show(struct device *dev,
726 				    struct device_attribute *attr, char *buf)
727 {
728 	struct regulator_dev *rdev = dev_get_drvdata(dev);
729 
730 	if (!rdev->constraints)
731 		return sprintf(buf, "constraint not defined\n");
732 
733 	return sprintf(buf, "%d\n", rdev->constraints->min_uV);
734 }
735 static DEVICE_ATTR(min_microvolts, 0444, regulator_min_uV_show, NULL);
736 
737 static ssize_t regulator_max_uV_show(struct device *dev,
738 				    struct device_attribute *attr, char *buf)
739 {
740 	struct regulator_dev *rdev = dev_get_drvdata(dev);
741 
742 	if (!rdev->constraints)
743 		return sprintf(buf, "constraint not defined\n");
744 
745 	return sprintf(buf, "%d\n", rdev->constraints->max_uV);
746 }
747 static DEVICE_ATTR(max_microvolts, 0444, regulator_max_uV_show, NULL);
748 
749 static ssize_t regulator_total_uA_show(struct device *dev,
750 				      struct device_attribute *attr, char *buf)
751 {
752 	struct regulator_dev *rdev = dev_get_drvdata(dev);
753 	struct regulator *regulator;
754 	int uA = 0;
755 
756 	regulator_lock(rdev);
757 	list_for_each_entry(regulator, &rdev->consumer_list, list) {
758 		if (regulator->enable_count)
759 			uA += regulator->uA_load;
760 	}
761 	regulator_unlock(rdev);
762 	return sprintf(buf, "%d\n", uA);
763 }
764 static DEVICE_ATTR(requested_microamps, 0444, regulator_total_uA_show, NULL);
765 
766 static ssize_t num_users_show(struct device *dev, struct device_attribute *attr,
767 			      char *buf)
768 {
769 	struct regulator_dev *rdev = dev_get_drvdata(dev);
770 	return sprintf(buf, "%d\n", rdev->use_count);
771 }
772 static DEVICE_ATTR_RO(num_users);
773 
774 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
775 			 char *buf)
776 {
777 	struct regulator_dev *rdev = dev_get_drvdata(dev);
778 
779 	switch (rdev->desc->type) {
780 	case REGULATOR_VOLTAGE:
781 		return sprintf(buf, "voltage\n");
782 	case REGULATOR_CURRENT:
783 		return sprintf(buf, "current\n");
784 	}
785 	return sprintf(buf, "unknown\n");
786 }
787 static DEVICE_ATTR_RO(type);
788 
789 static ssize_t regulator_suspend_mem_uV_show(struct device *dev,
790 				struct device_attribute *attr, char *buf)
791 {
792 	struct regulator_dev *rdev = dev_get_drvdata(dev);
793 
794 	return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
795 }
796 static DEVICE_ATTR(suspend_mem_microvolts, 0444,
797 		regulator_suspend_mem_uV_show, NULL);
798 
799 static ssize_t regulator_suspend_disk_uV_show(struct device *dev,
800 				struct device_attribute *attr, char *buf)
801 {
802 	struct regulator_dev *rdev = dev_get_drvdata(dev);
803 
804 	return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
805 }
806 static DEVICE_ATTR(suspend_disk_microvolts, 0444,
807 		regulator_suspend_disk_uV_show, NULL);
808 
809 static ssize_t regulator_suspend_standby_uV_show(struct device *dev,
810 				struct device_attribute *attr, char *buf)
811 {
812 	struct regulator_dev *rdev = dev_get_drvdata(dev);
813 
814 	return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
815 }
816 static DEVICE_ATTR(suspend_standby_microvolts, 0444,
817 		regulator_suspend_standby_uV_show, NULL);
818 
819 static ssize_t regulator_suspend_mem_mode_show(struct device *dev,
820 				struct device_attribute *attr, char *buf)
821 {
822 	struct regulator_dev *rdev = dev_get_drvdata(dev);
823 
824 	return regulator_print_opmode(buf,
825 		rdev->constraints->state_mem.mode);
826 }
827 static DEVICE_ATTR(suspend_mem_mode, 0444,
828 		regulator_suspend_mem_mode_show, NULL);
829 
830 static ssize_t regulator_suspend_disk_mode_show(struct device *dev,
831 				struct device_attribute *attr, char *buf)
832 {
833 	struct regulator_dev *rdev = dev_get_drvdata(dev);
834 
835 	return regulator_print_opmode(buf,
836 		rdev->constraints->state_disk.mode);
837 }
838 static DEVICE_ATTR(suspend_disk_mode, 0444,
839 		regulator_suspend_disk_mode_show, NULL);
840 
841 static ssize_t regulator_suspend_standby_mode_show(struct device *dev,
842 				struct device_attribute *attr, char *buf)
843 {
844 	struct regulator_dev *rdev = dev_get_drvdata(dev);
845 
846 	return regulator_print_opmode(buf,
847 		rdev->constraints->state_standby.mode);
848 }
849 static DEVICE_ATTR(suspend_standby_mode, 0444,
850 		regulator_suspend_standby_mode_show, NULL);
851 
852 static ssize_t regulator_suspend_mem_state_show(struct device *dev,
853 				   struct device_attribute *attr, char *buf)
854 {
855 	struct regulator_dev *rdev = dev_get_drvdata(dev);
856 
857 	return regulator_print_state(buf,
858 			rdev->constraints->state_mem.enabled);
859 }
860 static DEVICE_ATTR(suspend_mem_state, 0444,
861 		regulator_suspend_mem_state_show, NULL);
862 
863 static ssize_t regulator_suspend_disk_state_show(struct device *dev,
864 				   struct device_attribute *attr, char *buf)
865 {
866 	struct regulator_dev *rdev = dev_get_drvdata(dev);
867 
868 	return regulator_print_state(buf,
869 			rdev->constraints->state_disk.enabled);
870 }
871 static DEVICE_ATTR(suspend_disk_state, 0444,
872 		regulator_suspend_disk_state_show, NULL);
873 
874 static ssize_t regulator_suspend_standby_state_show(struct device *dev,
875 				   struct device_attribute *attr, char *buf)
876 {
877 	struct regulator_dev *rdev = dev_get_drvdata(dev);
878 
879 	return regulator_print_state(buf,
880 			rdev->constraints->state_standby.enabled);
881 }
882 static DEVICE_ATTR(suspend_standby_state, 0444,
883 		regulator_suspend_standby_state_show, NULL);
884 
885 static ssize_t regulator_bypass_show(struct device *dev,
886 				     struct device_attribute *attr, char *buf)
887 {
888 	struct regulator_dev *rdev = dev_get_drvdata(dev);
889 	const char *report;
890 	bool bypass;
891 	int ret;
892 
893 	ret = rdev->desc->ops->get_bypass(rdev, &bypass);
894 
895 	if (ret != 0)
896 		report = "unknown";
897 	else if (bypass)
898 		report = "enabled";
899 	else
900 		report = "disabled";
901 
902 	return sprintf(buf, "%s\n", report);
903 }
904 static DEVICE_ATTR(bypass, 0444,
905 		   regulator_bypass_show, NULL);
906 
907 /* Calculate the new optimum regulator operating mode based on the new total
908  * consumer load. All locks held by caller */
909 static int drms_uA_update(struct regulator_dev *rdev)
910 {
911 	struct regulator *sibling;
912 	int current_uA = 0, output_uV, input_uV, err;
913 	unsigned int mode;
914 
915 	/*
916 	 * first check to see if we can set modes at all, otherwise just
917 	 * tell the consumer everything is OK.
918 	 */
919 	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_DRMS)) {
920 		rdev_dbg(rdev, "DRMS operation not allowed\n");
921 		return 0;
922 	}
923 
924 	if (!rdev->desc->ops->get_optimum_mode &&
925 	    !rdev->desc->ops->set_load)
926 		return 0;
927 
928 	if (!rdev->desc->ops->set_mode &&
929 	    !rdev->desc->ops->set_load)
930 		return -EINVAL;
931 
932 	/* calc total requested load */
933 	list_for_each_entry(sibling, &rdev->consumer_list, list) {
934 		if (sibling->enable_count)
935 			current_uA += sibling->uA_load;
936 	}
937 
938 	current_uA += rdev->constraints->system_load;
939 
940 	if (rdev->desc->ops->set_load) {
941 		/* set the optimum mode for our new total regulator load */
942 		err = rdev->desc->ops->set_load(rdev, current_uA);
943 		if (err < 0)
944 			rdev_err(rdev, "failed to set load %d\n", current_uA);
945 	} else {
946 		/* get output voltage */
947 		output_uV = regulator_get_voltage_rdev(rdev);
948 		if (output_uV <= 0) {
949 			rdev_err(rdev, "invalid output voltage found\n");
950 			return -EINVAL;
951 		}
952 
953 		/* get input voltage */
954 		input_uV = 0;
955 		if (rdev->supply)
956 			input_uV = regulator_get_voltage(rdev->supply);
957 		if (input_uV <= 0)
958 			input_uV = rdev->constraints->input_uV;
959 		if (input_uV <= 0) {
960 			rdev_err(rdev, "invalid input voltage found\n");
961 			return -EINVAL;
962 		}
963 
964 		/* now get the optimum mode for our new total regulator load */
965 		mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
966 							 output_uV, current_uA);
967 
968 		/* check the new mode is allowed */
969 		err = regulator_mode_constrain(rdev, &mode);
970 		if (err < 0) {
971 			rdev_err(rdev, "failed to get optimum mode @ %d uA %d -> %d uV\n",
972 				 current_uA, input_uV, output_uV);
973 			return err;
974 		}
975 
976 		err = rdev->desc->ops->set_mode(rdev, mode);
977 		if (err < 0)
978 			rdev_err(rdev, "failed to set optimum mode %x\n", mode);
979 	}
980 
981 	return err;
982 }
983 
984 static int suspend_set_state(struct regulator_dev *rdev,
985 				    suspend_state_t state)
986 {
987 	int ret = 0;
988 	struct regulator_state *rstate;
989 
990 	rstate = regulator_get_suspend_state(rdev, state);
991 	if (rstate == NULL)
992 		return 0;
993 
994 	/* If we have no suspend mode configuration don't set anything;
995 	 * only warn if the driver implements set_suspend_voltage or
996 	 * set_suspend_mode callback.
997 	 */
998 	if (rstate->enabled != ENABLE_IN_SUSPEND &&
999 	    rstate->enabled != DISABLE_IN_SUSPEND) {
1000 		if (rdev->desc->ops->set_suspend_voltage ||
1001 		    rdev->desc->ops->set_suspend_mode)
1002 			rdev_warn(rdev, "No configuration\n");
1003 		return 0;
1004 	}
1005 
1006 	if (rstate->enabled == ENABLE_IN_SUSPEND &&
1007 		rdev->desc->ops->set_suspend_enable)
1008 		ret = rdev->desc->ops->set_suspend_enable(rdev);
1009 	else if (rstate->enabled == DISABLE_IN_SUSPEND &&
1010 		rdev->desc->ops->set_suspend_disable)
1011 		ret = rdev->desc->ops->set_suspend_disable(rdev);
1012 	else /* OK if set_suspend_enable or set_suspend_disable is NULL */
1013 		ret = 0;
1014 
1015 	if (ret < 0) {
1016 		rdev_err(rdev, "failed to enabled/disable\n");
1017 		return ret;
1018 	}
1019 
1020 	if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
1021 		ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
1022 		if (ret < 0) {
1023 			rdev_err(rdev, "failed to set voltage\n");
1024 			return ret;
1025 		}
1026 	}
1027 
1028 	if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
1029 		ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
1030 		if (ret < 0) {
1031 			rdev_err(rdev, "failed to set mode\n");
1032 			return ret;
1033 		}
1034 	}
1035 
1036 	return ret;
1037 }
1038 
1039 static void print_constraints(struct regulator_dev *rdev)
1040 {
1041 	struct regulation_constraints *constraints = rdev->constraints;
1042 	char buf[160] = "";
1043 	size_t len = sizeof(buf) - 1;
1044 	int count = 0;
1045 	int ret;
1046 
1047 	if (constraints->min_uV && constraints->max_uV) {
1048 		if (constraints->min_uV == constraints->max_uV)
1049 			count += scnprintf(buf + count, len - count, "%d mV ",
1050 					   constraints->min_uV / 1000);
1051 		else
1052 			count += scnprintf(buf + count, len - count,
1053 					   "%d <--> %d mV ",
1054 					   constraints->min_uV / 1000,
1055 					   constraints->max_uV / 1000);
1056 	}
1057 
1058 	if (!constraints->min_uV ||
1059 	    constraints->min_uV != constraints->max_uV) {
1060 		ret = regulator_get_voltage_rdev(rdev);
1061 		if (ret > 0)
1062 			count += scnprintf(buf + count, len - count,
1063 					   "at %d mV ", ret / 1000);
1064 	}
1065 
1066 	if (constraints->uV_offset)
1067 		count += scnprintf(buf + count, len - count, "%dmV offset ",
1068 				   constraints->uV_offset / 1000);
1069 
1070 	if (constraints->min_uA && constraints->max_uA) {
1071 		if (constraints->min_uA == constraints->max_uA)
1072 			count += scnprintf(buf + count, len - count, "%d mA ",
1073 					   constraints->min_uA / 1000);
1074 		else
1075 			count += scnprintf(buf + count, len - count,
1076 					   "%d <--> %d mA ",
1077 					   constraints->min_uA / 1000,
1078 					   constraints->max_uA / 1000);
1079 	}
1080 
1081 	if (!constraints->min_uA ||
1082 	    constraints->min_uA != constraints->max_uA) {
1083 		ret = _regulator_get_current_limit(rdev);
1084 		if (ret > 0)
1085 			count += scnprintf(buf + count, len - count,
1086 					   "at %d mA ", ret / 1000);
1087 	}
1088 
1089 	if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
1090 		count += scnprintf(buf + count, len - count, "fast ");
1091 	if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
1092 		count += scnprintf(buf + count, len - count, "normal ");
1093 	if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
1094 		count += scnprintf(buf + count, len - count, "idle ");
1095 	if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
1096 		count += scnprintf(buf + count, len - count, "standby");
1097 
1098 	if (!count)
1099 		scnprintf(buf, len, "no parameters");
1100 
1101 	rdev_dbg(rdev, "%s\n", buf);
1102 
1103 	if ((constraints->min_uV != constraints->max_uV) &&
1104 	    !regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE))
1105 		rdev_warn(rdev,
1106 			  "Voltage range but no REGULATOR_CHANGE_VOLTAGE\n");
1107 }
1108 
1109 static int machine_constraints_voltage(struct regulator_dev *rdev,
1110 	struct regulation_constraints *constraints)
1111 {
1112 	const struct regulator_ops *ops = rdev->desc->ops;
1113 	int ret;
1114 
1115 	/* do we need to apply the constraint voltage */
1116 	if (rdev->constraints->apply_uV &&
1117 	    rdev->constraints->min_uV && rdev->constraints->max_uV) {
1118 		int target_min, target_max;
1119 		int current_uV = regulator_get_voltage_rdev(rdev);
1120 
1121 		if (current_uV == -ENOTRECOVERABLE) {
1122 			/* This regulator can't be read and must be initialized */
1123 			rdev_info(rdev, "Setting %d-%duV\n",
1124 				  rdev->constraints->min_uV,
1125 				  rdev->constraints->max_uV);
1126 			_regulator_do_set_voltage(rdev,
1127 						  rdev->constraints->min_uV,
1128 						  rdev->constraints->max_uV);
1129 			current_uV = regulator_get_voltage_rdev(rdev);
1130 		}
1131 
1132 		if (current_uV < 0) {
1133 			rdev_err(rdev,
1134 				 "failed to get the current voltage(%d)\n",
1135 				 current_uV);
1136 			return current_uV;
1137 		}
1138 
1139 		/*
1140 		 * If we're below the minimum voltage move up to the
1141 		 * minimum voltage, if we're above the maximum voltage
1142 		 * then move down to the maximum.
1143 		 */
1144 		target_min = current_uV;
1145 		target_max = current_uV;
1146 
1147 		if (current_uV < rdev->constraints->min_uV) {
1148 			target_min = rdev->constraints->min_uV;
1149 			target_max = rdev->constraints->min_uV;
1150 		}
1151 
1152 		if (current_uV > rdev->constraints->max_uV) {
1153 			target_min = rdev->constraints->max_uV;
1154 			target_max = rdev->constraints->max_uV;
1155 		}
1156 
1157 		if (target_min != current_uV || target_max != current_uV) {
1158 			rdev_info(rdev, "Bringing %duV into %d-%duV\n",
1159 				  current_uV, target_min, target_max);
1160 			ret = _regulator_do_set_voltage(
1161 				rdev, target_min, target_max);
1162 			if (ret < 0) {
1163 				rdev_err(rdev,
1164 					"failed to apply %d-%duV constraint(%d)\n",
1165 					target_min, target_max, ret);
1166 				return ret;
1167 			}
1168 		}
1169 	}
1170 
1171 	/* constrain machine-level voltage specs to fit
1172 	 * the actual range supported by this regulator.
1173 	 */
1174 	if (ops->list_voltage && rdev->desc->n_voltages) {
1175 		int	count = rdev->desc->n_voltages;
1176 		int	i;
1177 		int	min_uV = INT_MAX;
1178 		int	max_uV = INT_MIN;
1179 		int	cmin = constraints->min_uV;
1180 		int	cmax = constraints->max_uV;
1181 
1182 		/* it's safe to autoconfigure fixed-voltage supplies
1183 		   and the constraints are used by list_voltage. */
1184 		if (count == 1 && !cmin) {
1185 			cmin = 1;
1186 			cmax = INT_MAX;
1187 			constraints->min_uV = cmin;
1188 			constraints->max_uV = cmax;
1189 		}
1190 
1191 		/* voltage constraints are optional */
1192 		if ((cmin == 0) && (cmax == 0))
1193 			return 0;
1194 
1195 		/* else require explicit machine-level constraints */
1196 		if (cmin <= 0 || cmax <= 0 || cmax < cmin) {
1197 			rdev_err(rdev, "invalid voltage constraints\n");
1198 			return -EINVAL;
1199 		}
1200 
1201 		/* no need to loop voltages if range is continuous */
1202 		if (rdev->desc->continuous_voltage_range)
1203 			return 0;
1204 
1205 		/* initial: [cmin..cmax] valid, [min_uV..max_uV] not */
1206 		for (i = 0; i < count; i++) {
1207 			int	value;
1208 
1209 			value = ops->list_voltage(rdev, i);
1210 			if (value <= 0)
1211 				continue;
1212 
1213 			/* maybe adjust [min_uV..max_uV] */
1214 			if (value >= cmin && value < min_uV)
1215 				min_uV = value;
1216 			if (value <= cmax && value > max_uV)
1217 				max_uV = value;
1218 		}
1219 
1220 		/* final: [min_uV..max_uV] valid iff constraints valid */
1221 		if (max_uV < min_uV) {
1222 			rdev_err(rdev,
1223 				 "unsupportable voltage constraints %u-%uuV\n",
1224 				 min_uV, max_uV);
1225 			return -EINVAL;
1226 		}
1227 
1228 		/* use regulator's subset of machine constraints */
1229 		if (constraints->min_uV < min_uV) {
1230 			rdev_dbg(rdev, "override min_uV, %d -> %d\n",
1231 				 constraints->min_uV, min_uV);
1232 			constraints->min_uV = min_uV;
1233 		}
1234 		if (constraints->max_uV > max_uV) {
1235 			rdev_dbg(rdev, "override max_uV, %d -> %d\n",
1236 				 constraints->max_uV, max_uV);
1237 			constraints->max_uV = max_uV;
1238 		}
1239 	}
1240 
1241 	return 0;
1242 }
1243 
1244 static int machine_constraints_current(struct regulator_dev *rdev,
1245 	struct regulation_constraints *constraints)
1246 {
1247 	const struct regulator_ops *ops = rdev->desc->ops;
1248 	int ret;
1249 
1250 	if (!constraints->min_uA && !constraints->max_uA)
1251 		return 0;
1252 
1253 	if (constraints->min_uA > constraints->max_uA) {
1254 		rdev_err(rdev, "Invalid current constraints\n");
1255 		return -EINVAL;
1256 	}
1257 
1258 	if (!ops->set_current_limit || !ops->get_current_limit) {
1259 		rdev_warn(rdev, "Operation of current configuration missing\n");
1260 		return 0;
1261 	}
1262 
1263 	/* Set regulator current in constraints range */
1264 	ret = ops->set_current_limit(rdev, constraints->min_uA,
1265 			constraints->max_uA);
1266 	if (ret < 0) {
1267 		rdev_err(rdev, "Failed to set current constraint, %d\n", ret);
1268 		return ret;
1269 	}
1270 
1271 	return 0;
1272 }
1273 
1274 static int _regulator_do_enable(struct regulator_dev *rdev);
1275 
1276 /**
1277  * set_machine_constraints - sets regulator constraints
1278  * @rdev: regulator source
1279  * @constraints: constraints to apply
1280  *
1281  * Allows platform initialisation code to define and constrain
1282  * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
1283  * Constraints *must* be set by platform code in order for some
1284  * regulator operations to proceed i.e. set_voltage, set_current_limit,
1285  * set_mode.
1286  */
1287 static int set_machine_constraints(struct regulator_dev *rdev,
1288 	const struct regulation_constraints *constraints)
1289 {
1290 	int ret = 0;
1291 	const struct regulator_ops *ops = rdev->desc->ops;
1292 
1293 	if (constraints)
1294 		rdev->constraints = kmemdup(constraints, sizeof(*constraints),
1295 					    GFP_KERNEL);
1296 	else
1297 		rdev->constraints = kzalloc(sizeof(*constraints),
1298 					    GFP_KERNEL);
1299 	if (!rdev->constraints)
1300 		return -ENOMEM;
1301 
1302 	ret = machine_constraints_voltage(rdev, rdev->constraints);
1303 	if (ret != 0)
1304 		return ret;
1305 
1306 	ret = machine_constraints_current(rdev, rdev->constraints);
1307 	if (ret != 0)
1308 		return ret;
1309 
1310 	if (rdev->constraints->ilim_uA && ops->set_input_current_limit) {
1311 		ret = ops->set_input_current_limit(rdev,
1312 						   rdev->constraints->ilim_uA);
1313 		if (ret < 0) {
1314 			rdev_err(rdev, "failed to set input limit\n");
1315 			return ret;
1316 		}
1317 	}
1318 
1319 	/* do we need to setup our suspend state */
1320 	if (rdev->constraints->initial_state) {
1321 		ret = suspend_set_state(rdev, rdev->constraints->initial_state);
1322 		if (ret < 0) {
1323 			rdev_err(rdev, "failed to set suspend state\n");
1324 			return ret;
1325 		}
1326 	}
1327 
1328 	if (rdev->constraints->initial_mode) {
1329 		if (!ops->set_mode) {
1330 			rdev_err(rdev, "no set_mode operation\n");
1331 			return -EINVAL;
1332 		}
1333 
1334 		ret = ops->set_mode(rdev, rdev->constraints->initial_mode);
1335 		if (ret < 0) {
1336 			rdev_err(rdev, "failed to set initial mode: %d\n", ret);
1337 			return ret;
1338 		}
1339 	} else if (rdev->constraints->system_load) {
1340 		/*
1341 		 * We'll only apply the initial system load if an
1342 		 * initial mode wasn't specified.
1343 		 */
1344 		drms_uA_update(rdev);
1345 	}
1346 
1347 	if ((rdev->constraints->ramp_delay || rdev->constraints->ramp_disable)
1348 		&& ops->set_ramp_delay) {
1349 		ret = ops->set_ramp_delay(rdev, rdev->constraints->ramp_delay);
1350 		if (ret < 0) {
1351 			rdev_err(rdev, "failed to set ramp_delay\n");
1352 			return ret;
1353 		}
1354 	}
1355 
1356 	if (rdev->constraints->pull_down && ops->set_pull_down) {
1357 		ret = ops->set_pull_down(rdev);
1358 		if (ret < 0) {
1359 			rdev_err(rdev, "failed to set pull down\n");
1360 			return ret;
1361 		}
1362 	}
1363 
1364 	if (rdev->constraints->soft_start && ops->set_soft_start) {
1365 		ret = ops->set_soft_start(rdev);
1366 		if (ret < 0) {
1367 			rdev_err(rdev, "failed to set soft start\n");
1368 			return ret;
1369 		}
1370 	}
1371 
1372 	if (rdev->constraints->over_current_protection
1373 		&& ops->set_over_current_protection) {
1374 		ret = ops->set_over_current_protection(rdev);
1375 		if (ret < 0) {
1376 			rdev_err(rdev, "failed to set over current protection\n");
1377 			return ret;
1378 		}
1379 	}
1380 
1381 	if (rdev->constraints->active_discharge && ops->set_active_discharge) {
1382 		bool ad_state = (rdev->constraints->active_discharge ==
1383 			      REGULATOR_ACTIVE_DISCHARGE_ENABLE) ? true : false;
1384 
1385 		ret = ops->set_active_discharge(rdev, ad_state);
1386 		if (ret < 0) {
1387 			rdev_err(rdev, "failed to set active discharge\n");
1388 			return ret;
1389 		}
1390 	}
1391 
1392 	/* If the constraints say the regulator should be on at this point
1393 	 * and we have control then make sure it is enabled.
1394 	 */
1395 	if (rdev->constraints->always_on || rdev->constraints->boot_on) {
1396 		if (rdev->supply) {
1397 			ret = regulator_enable(rdev->supply);
1398 			if (ret < 0) {
1399 				_regulator_put(rdev->supply);
1400 				rdev->supply = NULL;
1401 				return ret;
1402 			}
1403 		}
1404 
1405 		ret = _regulator_do_enable(rdev);
1406 		if (ret < 0 && ret != -EINVAL) {
1407 			rdev_err(rdev, "failed to enable\n");
1408 			return ret;
1409 		}
1410 
1411 		if (rdev->constraints->always_on)
1412 			rdev->use_count++;
1413 	}
1414 
1415 	print_constraints(rdev);
1416 	return 0;
1417 }
1418 
1419 /**
1420  * set_supply - set regulator supply regulator
1421  * @rdev: regulator name
1422  * @supply_rdev: supply regulator name
1423  *
1424  * Called by platform initialisation code to set the supply regulator for this
1425  * regulator. This ensures that a regulators supply will also be enabled by the
1426  * core if it's child is enabled.
1427  */
1428 static int set_supply(struct regulator_dev *rdev,
1429 		      struct regulator_dev *supply_rdev)
1430 {
1431 	int err;
1432 
1433 	rdev_info(rdev, "supplied by %s\n", rdev_get_name(supply_rdev));
1434 
1435 	if (!try_module_get(supply_rdev->owner))
1436 		return -ENODEV;
1437 
1438 	rdev->supply = create_regulator(supply_rdev, &rdev->dev, "SUPPLY");
1439 	if (rdev->supply == NULL) {
1440 		err = -ENOMEM;
1441 		return err;
1442 	}
1443 	supply_rdev->open_count++;
1444 
1445 	return 0;
1446 }
1447 
1448 /**
1449  * set_consumer_device_supply - Bind a regulator to a symbolic supply
1450  * @rdev:         regulator source
1451  * @consumer_dev_name: dev_name() string for device supply applies to
1452  * @supply:       symbolic name for supply
1453  *
1454  * Allows platform initialisation code to map physical regulator
1455  * sources to symbolic names for supplies for use by devices.  Devices
1456  * should use these symbolic names to request regulators, avoiding the
1457  * need to provide board-specific regulator names as platform data.
1458  */
1459 static int set_consumer_device_supply(struct regulator_dev *rdev,
1460 				      const char *consumer_dev_name,
1461 				      const char *supply)
1462 {
1463 	struct regulator_map *node;
1464 	int has_dev;
1465 
1466 	if (supply == NULL)
1467 		return -EINVAL;
1468 
1469 	if (consumer_dev_name != NULL)
1470 		has_dev = 1;
1471 	else
1472 		has_dev = 0;
1473 
1474 	list_for_each_entry(node, &regulator_map_list, list) {
1475 		if (node->dev_name && consumer_dev_name) {
1476 			if (strcmp(node->dev_name, consumer_dev_name) != 0)
1477 				continue;
1478 		} else if (node->dev_name || consumer_dev_name) {
1479 			continue;
1480 		}
1481 
1482 		if (strcmp(node->supply, supply) != 0)
1483 			continue;
1484 
1485 		pr_debug("%s: %s/%s is '%s' supply; fail %s/%s\n",
1486 			 consumer_dev_name,
1487 			 dev_name(&node->regulator->dev),
1488 			 node->regulator->desc->name,
1489 			 supply,
1490 			 dev_name(&rdev->dev), rdev_get_name(rdev));
1491 		return -EBUSY;
1492 	}
1493 
1494 	node = kzalloc(sizeof(struct regulator_map), GFP_KERNEL);
1495 	if (node == NULL)
1496 		return -ENOMEM;
1497 
1498 	node->regulator = rdev;
1499 	node->supply = supply;
1500 
1501 	if (has_dev) {
1502 		node->dev_name = kstrdup(consumer_dev_name, GFP_KERNEL);
1503 		if (node->dev_name == NULL) {
1504 			kfree(node);
1505 			return -ENOMEM;
1506 		}
1507 	}
1508 
1509 	list_add(&node->list, &regulator_map_list);
1510 	return 0;
1511 }
1512 
1513 static void unset_regulator_supplies(struct regulator_dev *rdev)
1514 {
1515 	struct regulator_map *node, *n;
1516 
1517 	list_for_each_entry_safe(node, n, &regulator_map_list, list) {
1518 		if (rdev == node->regulator) {
1519 			list_del(&node->list);
1520 			kfree(node->dev_name);
1521 			kfree(node);
1522 		}
1523 	}
1524 }
1525 
1526 #ifdef CONFIG_DEBUG_FS
1527 static ssize_t constraint_flags_read_file(struct file *file,
1528 					  char __user *user_buf,
1529 					  size_t count, loff_t *ppos)
1530 {
1531 	const struct regulator *regulator = file->private_data;
1532 	const struct regulation_constraints *c = regulator->rdev->constraints;
1533 	char *buf;
1534 	ssize_t ret;
1535 
1536 	if (!c)
1537 		return 0;
1538 
1539 	buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
1540 	if (!buf)
1541 		return -ENOMEM;
1542 
1543 	ret = snprintf(buf, PAGE_SIZE,
1544 			"always_on: %u\n"
1545 			"boot_on: %u\n"
1546 			"apply_uV: %u\n"
1547 			"ramp_disable: %u\n"
1548 			"soft_start: %u\n"
1549 			"pull_down: %u\n"
1550 			"over_current_protection: %u\n",
1551 			c->always_on,
1552 			c->boot_on,
1553 			c->apply_uV,
1554 			c->ramp_disable,
1555 			c->soft_start,
1556 			c->pull_down,
1557 			c->over_current_protection);
1558 
1559 	ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
1560 	kfree(buf);
1561 
1562 	return ret;
1563 }
1564 
1565 #endif
1566 
1567 static const struct file_operations constraint_flags_fops = {
1568 #ifdef CONFIG_DEBUG_FS
1569 	.open = simple_open,
1570 	.read = constraint_flags_read_file,
1571 	.llseek = default_llseek,
1572 #endif
1573 };
1574 
1575 #define REG_STR_SIZE	64
1576 
1577 static struct regulator *create_regulator(struct regulator_dev *rdev,
1578 					  struct device *dev,
1579 					  const char *supply_name)
1580 {
1581 	struct regulator *regulator;
1582 	char buf[REG_STR_SIZE];
1583 	int err, size;
1584 
1585 	regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
1586 	if (regulator == NULL)
1587 		return NULL;
1588 
1589 	regulator_lock(rdev);
1590 	regulator->rdev = rdev;
1591 	list_add(&regulator->list, &rdev->consumer_list);
1592 
1593 	if (dev) {
1594 		regulator->dev = dev;
1595 
1596 		/* Add a link to the device sysfs entry */
1597 		size = snprintf(buf, REG_STR_SIZE, "%s-%s",
1598 				dev->kobj.name, supply_name);
1599 		if (size >= REG_STR_SIZE)
1600 			goto overflow_err;
1601 
1602 		regulator->supply_name = kstrdup(buf, GFP_KERNEL);
1603 		if (regulator->supply_name == NULL)
1604 			goto overflow_err;
1605 
1606 		err = sysfs_create_link_nowarn(&rdev->dev.kobj, &dev->kobj,
1607 					buf);
1608 		if (err) {
1609 			rdev_dbg(rdev, "could not add device link %s err %d\n",
1610 				  dev->kobj.name, err);
1611 			/* non-fatal */
1612 		}
1613 	} else {
1614 		regulator->supply_name = kstrdup_const(supply_name, GFP_KERNEL);
1615 		if (regulator->supply_name == NULL)
1616 			goto overflow_err;
1617 	}
1618 
1619 	regulator->debugfs = debugfs_create_dir(regulator->supply_name,
1620 						rdev->debugfs);
1621 	if (!regulator->debugfs) {
1622 		rdev_dbg(rdev, "Failed to create debugfs directory\n");
1623 	} else {
1624 		debugfs_create_u32("uA_load", 0444, regulator->debugfs,
1625 				   &regulator->uA_load);
1626 		debugfs_create_u32("min_uV", 0444, regulator->debugfs,
1627 				   &regulator->voltage[PM_SUSPEND_ON].min_uV);
1628 		debugfs_create_u32("max_uV", 0444, regulator->debugfs,
1629 				   &regulator->voltage[PM_SUSPEND_ON].max_uV);
1630 		debugfs_create_file("constraint_flags", 0444,
1631 				    regulator->debugfs, regulator,
1632 				    &constraint_flags_fops);
1633 	}
1634 
1635 	/*
1636 	 * Check now if the regulator is an always on regulator - if
1637 	 * it is then we don't need to do nearly so much work for
1638 	 * enable/disable calls.
1639 	 */
1640 	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_STATUS) &&
1641 	    _regulator_is_enabled(rdev))
1642 		regulator->always_on = true;
1643 
1644 	regulator_unlock(rdev);
1645 	return regulator;
1646 overflow_err:
1647 	list_del(&regulator->list);
1648 	kfree(regulator);
1649 	regulator_unlock(rdev);
1650 	return NULL;
1651 }
1652 
1653 static int _regulator_get_enable_time(struct regulator_dev *rdev)
1654 {
1655 	if (rdev->constraints && rdev->constraints->enable_time)
1656 		return rdev->constraints->enable_time;
1657 	if (rdev->desc->ops->enable_time)
1658 		return rdev->desc->ops->enable_time(rdev);
1659 	return rdev->desc->enable_time;
1660 }
1661 
1662 static struct regulator_supply_alias *regulator_find_supply_alias(
1663 		struct device *dev, const char *supply)
1664 {
1665 	struct regulator_supply_alias *map;
1666 
1667 	list_for_each_entry(map, &regulator_supply_alias_list, list)
1668 		if (map->src_dev == dev && strcmp(map->src_supply, supply) == 0)
1669 			return map;
1670 
1671 	return NULL;
1672 }
1673 
1674 static void regulator_supply_alias(struct device **dev, const char **supply)
1675 {
1676 	struct regulator_supply_alias *map;
1677 
1678 	map = regulator_find_supply_alias(*dev, *supply);
1679 	if (map) {
1680 		dev_dbg(*dev, "Mapping supply %s to %s,%s\n",
1681 				*supply, map->alias_supply,
1682 				dev_name(map->alias_dev));
1683 		*dev = map->alias_dev;
1684 		*supply = map->alias_supply;
1685 	}
1686 }
1687 
1688 static int regulator_match(struct device *dev, const void *data)
1689 {
1690 	struct regulator_dev *r = dev_to_rdev(dev);
1691 
1692 	return strcmp(rdev_get_name(r), data) == 0;
1693 }
1694 
1695 static struct regulator_dev *regulator_lookup_by_name(const char *name)
1696 {
1697 	struct device *dev;
1698 
1699 	dev = class_find_device(&regulator_class, NULL, name, regulator_match);
1700 
1701 	return dev ? dev_to_rdev(dev) : NULL;
1702 }
1703 
1704 /**
1705  * regulator_dev_lookup - lookup a regulator device.
1706  * @dev: device for regulator "consumer".
1707  * @supply: Supply name or regulator ID.
1708  *
1709  * If successful, returns a struct regulator_dev that corresponds to the name
1710  * @supply and with the embedded struct device refcount incremented by one.
1711  * The refcount must be dropped by calling put_device().
1712  * On failure one of the following ERR-PTR-encoded values is returned:
1713  * -ENODEV if lookup fails permanently, -EPROBE_DEFER if lookup could succeed
1714  * in the future.
1715  */
1716 static struct regulator_dev *regulator_dev_lookup(struct device *dev,
1717 						  const char *supply)
1718 {
1719 	struct regulator_dev *r = NULL;
1720 	struct device_node *node;
1721 	struct regulator_map *map;
1722 	const char *devname = NULL;
1723 
1724 	regulator_supply_alias(&dev, &supply);
1725 
1726 	/* first do a dt based lookup */
1727 	if (dev && dev->of_node) {
1728 		node = of_get_regulator(dev, supply);
1729 		if (node) {
1730 			r = of_find_regulator_by_node(node);
1731 			if (r)
1732 				return r;
1733 
1734 			/*
1735 			 * We have a node, but there is no device.
1736 			 * assume it has not registered yet.
1737 			 */
1738 			return ERR_PTR(-EPROBE_DEFER);
1739 		}
1740 	}
1741 
1742 	/* if not found, try doing it non-dt way */
1743 	if (dev)
1744 		devname = dev_name(dev);
1745 
1746 	mutex_lock(&regulator_list_mutex);
1747 	list_for_each_entry(map, &regulator_map_list, list) {
1748 		/* If the mapping has a device set up it must match */
1749 		if (map->dev_name &&
1750 		    (!devname || strcmp(map->dev_name, devname)))
1751 			continue;
1752 
1753 		if (strcmp(map->supply, supply) == 0 &&
1754 		    get_device(&map->regulator->dev)) {
1755 			r = map->regulator;
1756 			break;
1757 		}
1758 	}
1759 	mutex_unlock(&regulator_list_mutex);
1760 
1761 	if (r)
1762 		return r;
1763 
1764 	r = regulator_lookup_by_name(supply);
1765 	if (r)
1766 		return r;
1767 
1768 	return ERR_PTR(-ENODEV);
1769 }
1770 
1771 static int regulator_resolve_supply(struct regulator_dev *rdev)
1772 {
1773 	struct regulator_dev *r;
1774 	struct device *dev = rdev->dev.parent;
1775 	int ret;
1776 
1777 	/* No supply to resolve? */
1778 	if (!rdev->supply_name)
1779 		return 0;
1780 
1781 	/* Supply already resolved? */
1782 	if (rdev->supply)
1783 		return 0;
1784 
1785 	r = regulator_dev_lookup(dev, rdev->supply_name);
1786 	if (IS_ERR(r)) {
1787 		ret = PTR_ERR(r);
1788 
1789 		/* Did the lookup explicitly defer for us? */
1790 		if (ret == -EPROBE_DEFER)
1791 			return ret;
1792 
1793 		if (have_full_constraints()) {
1794 			r = dummy_regulator_rdev;
1795 			get_device(&r->dev);
1796 		} else {
1797 			dev_err(dev, "Failed to resolve %s-supply for %s\n",
1798 				rdev->supply_name, rdev->desc->name);
1799 			return -EPROBE_DEFER;
1800 		}
1801 	}
1802 
1803 	/*
1804 	 * If the supply's parent device is not the same as the
1805 	 * regulator's parent device, then ensure the parent device
1806 	 * is bound before we resolve the supply, in case the parent
1807 	 * device get probe deferred and unregisters the supply.
1808 	 */
1809 	if (r->dev.parent && r->dev.parent != rdev->dev.parent) {
1810 		if (!device_is_bound(r->dev.parent)) {
1811 			put_device(&r->dev);
1812 			return -EPROBE_DEFER;
1813 		}
1814 	}
1815 
1816 	/* Recursively resolve the supply of the supply */
1817 	ret = regulator_resolve_supply(r);
1818 	if (ret < 0) {
1819 		put_device(&r->dev);
1820 		return ret;
1821 	}
1822 
1823 	ret = set_supply(rdev, r);
1824 	if (ret < 0) {
1825 		put_device(&r->dev);
1826 		return ret;
1827 	}
1828 
1829 	/*
1830 	 * In set_machine_constraints() we may have turned this regulator on
1831 	 * but we couldn't propagate to the supply if it hadn't been resolved
1832 	 * yet.  Do it now.
1833 	 */
1834 	if (rdev->use_count) {
1835 		ret = regulator_enable(rdev->supply);
1836 		if (ret < 0) {
1837 			_regulator_put(rdev->supply);
1838 			rdev->supply = NULL;
1839 			return ret;
1840 		}
1841 	}
1842 
1843 	return 0;
1844 }
1845 
1846 /* Internal regulator request function */
1847 struct regulator *_regulator_get(struct device *dev, const char *id,
1848 				 enum regulator_get_type get_type)
1849 {
1850 	struct regulator_dev *rdev;
1851 	struct regulator *regulator;
1852 	struct device_link *link;
1853 	int ret;
1854 
1855 	if (get_type >= MAX_GET_TYPE) {
1856 		dev_err(dev, "invalid type %d in %s\n", get_type, __func__);
1857 		return ERR_PTR(-EINVAL);
1858 	}
1859 
1860 	if (id == NULL) {
1861 		pr_err("get() with no identifier\n");
1862 		return ERR_PTR(-EINVAL);
1863 	}
1864 
1865 	rdev = regulator_dev_lookup(dev, id);
1866 	if (IS_ERR(rdev)) {
1867 		ret = PTR_ERR(rdev);
1868 
1869 		/*
1870 		 * If regulator_dev_lookup() fails with error other
1871 		 * than -ENODEV our job here is done, we simply return it.
1872 		 */
1873 		if (ret != -ENODEV)
1874 			return ERR_PTR(ret);
1875 
1876 		if (!have_full_constraints()) {
1877 			dev_warn(dev,
1878 				 "incomplete constraints, dummy supplies not allowed\n");
1879 			return ERR_PTR(-ENODEV);
1880 		}
1881 
1882 		switch (get_type) {
1883 		case NORMAL_GET:
1884 			/*
1885 			 * Assume that a regulator is physically present and
1886 			 * enabled, even if it isn't hooked up, and just
1887 			 * provide a dummy.
1888 			 */
1889 			dev_warn(dev, "supply %s not found, using dummy regulator\n", id);
1890 			rdev = dummy_regulator_rdev;
1891 			get_device(&rdev->dev);
1892 			break;
1893 
1894 		case EXCLUSIVE_GET:
1895 			dev_warn(dev,
1896 				 "dummy supplies not allowed for exclusive requests\n");
1897 			/* fall through */
1898 
1899 		default:
1900 			return ERR_PTR(-ENODEV);
1901 		}
1902 	}
1903 
1904 	if (rdev->exclusive) {
1905 		regulator = ERR_PTR(-EPERM);
1906 		put_device(&rdev->dev);
1907 		return regulator;
1908 	}
1909 
1910 	if (get_type == EXCLUSIVE_GET && rdev->open_count) {
1911 		regulator = ERR_PTR(-EBUSY);
1912 		put_device(&rdev->dev);
1913 		return regulator;
1914 	}
1915 
1916 	mutex_lock(&regulator_list_mutex);
1917 	ret = (rdev->coupling_desc.n_resolved != rdev->coupling_desc.n_coupled);
1918 	mutex_unlock(&regulator_list_mutex);
1919 
1920 	if (ret != 0) {
1921 		regulator = ERR_PTR(-EPROBE_DEFER);
1922 		put_device(&rdev->dev);
1923 		return regulator;
1924 	}
1925 
1926 	ret = regulator_resolve_supply(rdev);
1927 	if (ret < 0) {
1928 		regulator = ERR_PTR(ret);
1929 		put_device(&rdev->dev);
1930 		return regulator;
1931 	}
1932 
1933 	if (!try_module_get(rdev->owner)) {
1934 		regulator = ERR_PTR(-EPROBE_DEFER);
1935 		put_device(&rdev->dev);
1936 		return regulator;
1937 	}
1938 
1939 	regulator = create_regulator(rdev, dev, id);
1940 	if (regulator == NULL) {
1941 		regulator = ERR_PTR(-ENOMEM);
1942 		module_put(rdev->owner);
1943 		put_device(&rdev->dev);
1944 		return regulator;
1945 	}
1946 
1947 	rdev->open_count++;
1948 	if (get_type == EXCLUSIVE_GET) {
1949 		rdev->exclusive = 1;
1950 
1951 		ret = _regulator_is_enabled(rdev);
1952 		if (ret > 0)
1953 			rdev->use_count = 1;
1954 		else
1955 			rdev->use_count = 0;
1956 	}
1957 
1958 	link = device_link_add(dev, &rdev->dev, DL_FLAG_STATELESS);
1959 	if (!IS_ERR_OR_NULL(link))
1960 		regulator->device_link = true;
1961 
1962 	return regulator;
1963 }
1964 
1965 /**
1966  * regulator_get - lookup and obtain a reference to a regulator.
1967  * @dev: device for regulator "consumer"
1968  * @id: Supply name or regulator ID.
1969  *
1970  * Returns a struct regulator corresponding to the regulator producer,
1971  * or IS_ERR() condition containing errno.
1972  *
1973  * Use of supply names configured via regulator_set_device_supply() is
1974  * strongly encouraged.  It is recommended that the supply name used
1975  * should match the name used for the supply and/or the relevant
1976  * device pins in the datasheet.
1977  */
1978 struct regulator *regulator_get(struct device *dev, const char *id)
1979 {
1980 	return _regulator_get(dev, id, NORMAL_GET);
1981 }
1982 EXPORT_SYMBOL_GPL(regulator_get);
1983 
1984 /**
1985  * regulator_get_exclusive - obtain exclusive access to a regulator.
1986  * @dev: device for regulator "consumer"
1987  * @id: Supply name or regulator ID.
1988  *
1989  * Returns a struct regulator corresponding to the regulator producer,
1990  * or IS_ERR() condition containing errno.  Other consumers will be
1991  * unable to obtain this regulator while this reference is held and the
1992  * use count for the regulator will be initialised to reflect the current
1993  * state of the regulator.
1994  *
1995  * This is intended for use by consumers which cannot tolerate shared
1996  * use of the regulator such as those which need to force the
1997  * regulator off for correct operation of the hardware they are
1998  * controlling.
1999  *
2000  * Use of supply names configured via regulator_set_device_supply() is
2001  * strongly encouraged.  It is recommended that the supply name used
2002  * should match the name used for the supply and/or the relevant
2003  * device pins in the datasheet.
2004  */
2005 struct regulator *regulator_get_exclusive(struct device *dev, const char *id)
2006 {
2007 	return _regulator_get(dev, id, EXCLUSIVE_GET);
2008 }
2009 EXPORT_SYMBOL_GPL(regulator_get_exclusive);
2010 
2011 /**
2012  * regulator_get_optional - obtain optional access to a regulator.
2013  * @dev: device for regulator "consumer"
2014  * @id: Supply name or regulator ID.
2015  *
2016  * Returns a struct regulator corresponding to the regulator producer,
2017  * or IS_ERR() condition containing errno.
2018  *
2019  * This is intended for use by consumers for devices which can have
2020  * some supplies unconnected in normal use, such as some MMC devices.
2021  * It can allow the regulator core to provide stub supplies for other
2022  * supplies requested using normal regulator_get() calls without
2023  * disrupting the operation of drivers that can handle absent
2024  * supplies.
2025  *
2026  * Use of supply names configured via regulator_set_device_supply() is
2027  * strongly encouraged.  It is recommended that the supply name used
2028  * should match the name used for the supply and/or the relevant
2029  * device pins in the datasheet.
2030  */
2031 struct regulator *regulator_get_optional(struct device *dev, const char *id)
2032 {
2033 	return _regulator_get(dev, id, OPTIONAL_GET);
2034 }
2035 EXPORT_SYMBOL_GPL(regulator_get_optional);
2036 
2037 /* regulator_list_mutex lock held by regulator_put() */
2038 static void _regulator_put(struct regulator *regulator)
2039 {
2040 	struct regulator_dev *rdev;
2041 
2042 	if (IS_ERR_OR_NULL(regulator))
2043 		return;
2044 
2045 	lockdep_assert_held_once(&regulator_list_mutex);
2046 
2047 	/* Docs say you must disable before calling regulator_put() */
2048 	WARN_ON(regulator->enable_count);
2049 
2050 	rdev = regulator->rdev;
2051 
2052 	debugfs_remove_recursive(regulator->debugfs);
2053 
2054 	if (regulator->dev) {
2055 		if (regulator->device_link)
2056 			device_link_remove(regulator->dev, &rdev->dev);
2057 
2058 		/* remove any sysfs entries */
2059 		sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
2060 	}
2061 
2062 	regulator_lock(rdev);
2063 	list_del(&regulator->list);
2064 
2065 	rdev->open_count--;
2066 	rdev->exclusive = 0;
2067 	regulator_unlock(rdev);
2068 
2069 	kfree_const(regulator->supply_name);
2070 	kfree(regulator);
2071 
2072 	module_put(rdev->owner);
2073 	put_device(&rdev->dev);
2074 }
2075 
2076 /**
2077  * regulator_put - "free" the regulator source
2078  * @regulator: regulator source
2079  *
2080  * Note: drivers must ensure that all regulator_enable calls made on this
2081  * regulator source are balanced by regulator_disable calls prior to calling
2082  * this function.
2083  */
2084 void regulator_put(struct regulator *regulator)
2085 {
2086 	mutex_lock(&regulator_list_mutex);
2087 	_regulator_put(regulator);
2088 	mutex_unlock(&regulator_list_mutex);
2089 }
2090 EXPORT_SYMBOL_GPL(regulator_put);
2091 
2092 /**
2093  * regulator_register_supply_alias - Provide device alias for supply lookup
2094  *
2095  * @dev: device that will be given as the regulator "consumer"
2096  * @id: Supply name or regulator ID
2097  * @alias_dev: device that should be used to lookup the supply
2098  * @alias_id: Supply name or regulator ID that should be used to lookup the
2099  * supply
2100  *
2101  * All lookups for id on dev will instead be conducted for alias_id on
2102  * alias_dev.
2103  */
2104 int regulator_register_supply_alias(struct device *dev, const char *id,
2105 				    struct device *alias_dev,
2106 				    const char *alias_id)
2107 {
2108 	struct regulator_supply_alias *map;
2109 
2110 	map = regulator_find_supply_alias(dev, id);
2111 	if (map)
2112 		return -EEXIST;
2113 
2114 	map = kzalloc(sizeof(struct regulator_supply_alias), GFP_KERNEL);
2115 	if (!map)
2116 		return -ENOMEM;
2117 
2118 	map->src_dev = dev;
2119 	map->src_supply = id;
2120 	map->alias_dev = alias_dev;
2121 	map->alias_supply = alias_id;
2122 
2123 	list_add(&map->list, &regulator_supply_alias_list);
2124 
2125 	pr_info("Adding alias for supply %s,%s -> %s,%s\n",
2126 		id, dev_name(dev), alias_id, dev_name(alias_dev));
2127 
2128 	return 0;
2129 }
2130 EXPORT_SYMBOL_GPL(regulator_register_supply_alias);
2131 
2132 /**
2133  * regulator_unregister_supply_alias - Remove device alias
2134  *
2135  * @dev: device that will be given as the regulator "consumer"
2136  * @id: Supply name or regulator ID
2137  *
2138  * Remove a lookup alias if one exists for id on dev.
2139  */
2140 void regulator_unregister_supply_alias(struct device *dev, const char *id)
2141 {
2142 	struct regulator_supply_alias *map;
2143 
2144 	map = regulator_find_supply_alias(dev, id);
2145 	if (map) {
2146 		list_del(&map->list);
2147 		kfree(map);
2148 	}
2149 }
2150 EXPORT_SYMBOL_GPL(regulator_unregister_supply_alias);
2151 
2152 /**
2153  * regulator_bulk_register_supply_alias - register multiple aliases
2154  *
2155  * @dev: device that will be given as the regulator "consumer"
2156  * @id: List of supply names or regulator IDs
2157  * @alias_dev: device that should be used to lookup the supply
2158  * @alias_id: List of supply names or regulator IDs that should be used to
2159  * lookup the supply
2160  * @num_id: Number of aliases to register
2161  *
2162  * @return 0 on success, an errno on failure.
2163  *
2164  * This helper function allows drivers to register several supply
2165  * aliases in one operation.  If any of the aliases cannot be
2166  * registered any aliases that were registered will be removed
2167  * before returning to the caller.
2168  */
2169 int regulator_bulk_register_supply_alias(struct device *dev,
2170 					 const char *const *id,
2171 					 struct device *alias_dev,
2172 					 const char *const *alias_id,
2173 					 int num_id)
2174 {
2175 	int i;
2176 	int ret;
2177 
2178 	for (i = 0; i < num_id; ++i) {
2179 		ret = regulator_register_supply_alias(dev, id[i], alias_dev,
2180 						      alias_id[i]);
2181 		if (ret < 0)
2182 			goto err;
2183 	}
2184 
2185 	return 0;
2186 
2187 err:
2188 	dev_err(dev,
2189 		"Failed to create supply alias %s,%s -> %s,%s\n",
2190 		id[i], dev_name(dev), alias_id[i], dev_name(alias_dev));
2191 
2192 	while (--i >= 0)
2193 		regulator_unregister_supply_alias(dev, id[i]);
2194 
2195 	return ret;
2196 }
2197 EXPORT_SYMBOL_GPL(regulator_bulk_register_supply_alias);
2198 
2199 /**
2200  * regulator_bulk_unregister_supply_alias - unregister multiple aliases
2201  *
2202  * @dev: device that will be given as the regulator "consumer"
2203  * @id: List of supply names or regulator IDs
2204  * @num_id: Number of aliases to unregister
2205  *
2206  * This helper function allows drivers to unregister several supply
2207  * aliases in one operation.
2208  */
2209 void regulator_bulk_unregister_supply_alias(struct device *dev,
2210 					    const char *const *id,
2211 					    int num_id)
2212 {
2213 	int i;
2214 
2215 	for (i = 0; i < num_id; ++i)
2216 		regulator_unregister_supply_alias(dev, id[i]);
2217 }
2218 EXPORT_SYMBOL_GPL(regulator_bulk_unregister_supply_alias);
2219 
2220 
2221 /* Manage enable GPIO list. Same GPIO pin can be shared among regulators */
2222 static int regulator_ena_gpio_request(struct regulator_dev *rdev,
2223 				const struct regulator_config *config)
2224 {
2225 	struct regulator_enable_gpio *pin;
2226 	struct gpio_desc *gpiod;
2227 
2228 	gpiod = config->ena_gpiod;
2229 
2230 	list_for_each_entry(pin, &regulator_ena_gpio_list, list) {
2231 		if (pin->gpiod == gpiod) {
2232 			rdev_dbg(rdev, "GPIO is already used\n");
2233 			goto update_ena_gpio_to_rdev;
2234 		}
2235 	}
2236 
2237 	pin = kzalloc(sizeof(struct regulator_enable_gpio), GFP_KERNEL);
2238 	if (pin == NULL)
2239 		return -ENOMEM;
2240 
2241 	pin->gpiod = gpiod;
2242 	list_add(&pin->list, &regulator_ena_gpio_list);
2243 
2244 update_ena_gpio_to_rdev:
2245 	pin->request_count++;
2246 	rdev->ena_pin = pin;
2247 	return 0;
2248 }
2249 
2250 static void regulator_ena_gpio_free(struct regulator_dev *rdev)
2251 {
2252 	struct regulator_enable_gpio *pin, *n;
2253 
2254 	if (!rdev->ena_pin)
2255 		return;
2256 
2257 	/* Free the GPIO only in case of no use */
2258 	list_for_each_entry_safe(pin, n, &regulator_ena_gpio_list, list) {
2259 		if (pin->gpiod == rdev->ena_pin->gpiod) {
2260 			if (pin->request_count <= 1) {
2261 				pin->request_count = 0;
2262 				gpiod_put(pin->gpiod);
2263 				list_del(&pin->list);
2264 				kfree(pin);
2265 				rdev->ena_pin = NULL;
2266 				return;
2267 			} else {
2268 				pin->request_count--;
2269 			}
2270 		}
2271 	}
2272 }
2273 
2274 /**
2275  * regulator_ena_gpio_ctrl - balance enable_count of each GPIO and actual GPIO pin control
2276  * @rdev: regulator_dev structure
2277  * @enable: enable GPIO at initial use?
2278  *
2279  * GPIO is enabled in case of initial use. (enable_count is 0)
2280  * GPIO is disabled when it is not shared any more. (enable_count <= 1)
2281  */
2282 static int regulator_ena_gpio_ctrl(struct regulator_dev *rdev, bool enable)
2283 {
2284 	struct regulator_enable_gpio *pin = rdev->ena_pin;
2285 
2286 	if (!pin)
2287 		return -EINVAL;
2288 
2289 	if (enable) {
2290 		/* Enable GPIO at initial use */
2291 		if (pin->enable_count == 0)
2292 			gpiod_set_value_cansleep(pin->gpiod, 1);
2293 
2294 		pin->enable_count++;
2295 	} else {
2296 		if (pin->enable_count > 1) {
2297 			pin->enable_count--;
2298 			return 0;
2299 		}
2300 
2301 		/* Disable GPIO if not used */
2302 		if (pin->enable_count <= 1) {
2303 			gpiod_set_value_cansleep(pin->gpiod, 0);
2304 			pin->enable_count = 0;
2305 		}
2306 	}
2307 
2308 	return 0;
2309 }
2310 
2311 /**
2312  * _regulator_enable_delay - a delay helper function
2313  * @delay: time to delay in microseconds
2314  *
2315  * Delay for the requested amount of time as per the guidelines in:
2316  *
2317  *     Documentation/timers/timers-howto.rst
2318  *
2319  * The assumption here is that regulators will never be enabled in
2320  * atomic context and therefore sleeping functions can be used.
2321  */
2322 static void _regulator_enable_delay(unsigned int delay)
2323 {
2324 	unsigned int ms = delay / 1000;
2325 	unsigned int us = delay % 1000;
2326 
2327 	if (ms > 0) {
2328 		/*
2329 		 * For small enough values, handle super-millisecond
2330 		 * delays in the usleep_range() call below.
2331 		 */
2332 		if (ms < 20)
2333 			us += ms * 1000;
2334 		else
2335 			msleep(ms);
2336 	}
2337 
2338 	/*
2339 	 * Give the scheduler some room to coalesce with any other
2340 	 * wakeup sources. For delays shorter than 10 us, don't even
2341 	 * bother setting up high-resolution timers and just busy-
2342 	 * loop.
2343 	 */
2344 	if (us >= 10)
2345 		usleep_range(us, us + 100);
2346 	else
2347 		udelay(us);
2348 }
2349 
2350 static int _regulator_do_enable(struct regulator_dev *rdev)
2351 {
2352 	int ret, delay;
2353 
2354 	/* Query before enabling in case configuration dependent.  */
2355 	ret = _regulator_get_enable_time(rdev);
2356 	if (ret >= 0) {
2357 		delay = ret;
2358 	} else {
2359 		rdev_warn(rdev, "enable_time() failed: %d\n", ret);
2360 		delay = 0;
2361 	}
2362 
2363 	trace_regulator_enable(rdev_get_name(rdev));
2364 
2365 	if (rdev->desc->off_on_delay) {
2366 		/* if needed, keep a distance of off_on_delay from last time
2367 		 * this regulator was disabled.
2368 		 */
2369 		unsigned long start_jiffy = jiffies;
2370 		unsigned long intended, max_delay, remaining;
2371 
2372 		max_delay = usecs_to_jiffies(rdev->desc->off_on_delay);
2373 		intended = rdev->last_off_jiffy + max_delay;
2374 
2375 		if (time_before(start_jiffy, intended)) {
2376 			/* calc remaining jiffies to deal with one-time
2377 			 * timer wrapping.
2378 			 * in case of multiple timer wrapping, either it can be
2379 			 * detected by out-of-range remaining, or it cannot be
2380 			 * detected and we get a penalty of
2381 			 * _regulator_enable_delay().
2382 			 */
2383 			remaining = intended - start_jiffy;
2384 			if (remaining <= max_delay)
2385 				_regulator_enable_delay(
2386 						jiffies_to_usecs(remaining));
2387 		}
2388 	}
2389 
2390 	if (rdev->ena_pin) {
2391 		if (!rdev->ena_gpio_state) {
2392 			ret = regulator_ena_gpio_ctrl(rdev, true);
2393 			if (ret < 0)
2394 				return ret;
2395 			rdev->ena_gpio_state = 1;
2396 		}
2397 	} else if (rdev->desc->ops->enable) {
2398 		ret = rdev->desc->ops->enable(rdev);
2399 		if (ret < 0)
2400 			return ret;
2401 	} else {
2402 		return -EINVAL;
2403 	}
2404 
2405 	/* Allow the regulator to ramp; it would be useful to extend
2406 	 * this for bulk operations so that the regulators can ramp
2407 	 * together.  */
2408 	trace_regulator_enable_delay(rdev_get_name(rdev));
2409 
2410 	_regulator_enable_delay(delay);
2411 
2412 	trace_regulator_enable_complete(rdev_get_name(rdev));
2413 
2414 	return 0;
2415 }
2416 
2417 /**
2418  * _regulator_handle_consumer_enable - handle that a consumer enabled
2419  * @regulator: regulator source
2420  *
2421  * Some things on a regulator consumer (like the contribution towards total
2422  * load on the regulator) only have an effect when the consumer wants the
2423  * regulator enabled.  Explained in example with two consumers of the same
2424  * regulator:
2425  *   consumer A: set_load(100);       => total load = 0
2426  *   consumer A: regulator_enable();  => total load = 100
2427  *   consumer B: set_load(1000);      => total load = 100
2428  *   consumer B: regulator_enable();  => total load = 1100
2429  *   consumer A: regulator_disable(); => total_load = 1000
2430  *
2431  * This function (together with _regulator_handle_consumer_disable) is
2432  * responsible for keeping track of the refcount for a given regulator consumer
2433  * and applying / unapplying these things.
2434  *
2435  * Returns 0 upon no error; -error upon error.
2436  */
2437 static int _regulator_handle_consumer_enable(struct regulator *regulator)
2438 {
2439 	struct regulator_dev *rdev = regulator->rdev;
2440 
2441 	lockdep_assert_held_once(&rdev->mutex.base);
2442 
2443 	regulator->enable_count++;
2444 	if (regulator->uA_load && regulator->enable_count == 1)
2445 		return drms_uA_update(rdev);
2446 
2447 	return 0;
2448 }
2449 
2450 /**
2451  * _regulator_handle_consumer_disable - handle that a consumer disabled
2452  * @regulator: regulator source
2453  *
2454  * The opposite of _regulator_handle_consumer_enable().
2455  *
2456  * Returns 0 upon no error; -error upon error.
2457  */
2458 static int _regulator_handle_consumer_disable(struct regulator *regulator)
2459 {
2460 	struct regulator_dev *rdev = regulator->rdev;
2461 
2462 	lockdep_assert_held_once(&rdev->mutex.base);
2463 
2464 	if (!regulator->enable_count) {
2465 		rdev_err(rdev, "Underflow of regulator enable count\n");
2466 		return -EINVAL;
2467 	}
2468 
2469 	regulator->enable_count--;
2470 	if (regulator->uA_load && regulator->enable_count == 0)
2471 		return drms_uA_update(rdev);
2472 
2473 	return 0;
2474 }
2475 
2476 /* locks held by regulator_enable() */
2477 static int _regulator_enable(struct regulator *regulator)
2478 {
2479 	struct regulator_dev *rdev = regulator->rdev;
2480 	int ret;
2481 
2482 	lockdep_assert_held_once(&rdev->mutex.base);
2483 
2484 	if (rdev->use_count == 0 && rdev->supply) {
2485 		ret = _regulator_enable(rdev->supply);
2486 		if (ret < 0)
2487 			return ret;
2488 	}
2489 
2490 	/* balance only if there are regulators coupled */
2491 	if (rdev->coupling_desc.n_coupled > 1) {
2492 		ret = regulator_balance_voltage(rdev, PM_SUSPEND_ON);
2493 		if (ret < 0)
2494 			goto err_disable_supply;
2495 	}
2496 
2497 	ret = _regulator_handle_consumer_enable(regulator);
2498 	if (ret < 0)
2499 		goto err_disable_supply;
2500 
2501 	if (rdev->use_count == 0) {
2502 		/* The regulator may on if it's not switchable or left on */
2503 		ret = _regulator_is_enabled(rdev);
2504 		if (ret == -EINVAL || ret == 0) {
2505 			if (!regulator_ops_is_valid(rdev,
2506 					REGULATOR_CHANGE_STATUS)) {
2507 				ret = -EPERM;
2508 				goto err_consumer_disable;
2509 			}
2510 
2511 			ret = _regulator_do_enable(rdev);
2512 			if (ret < 0)
2513 				goto err_consumer_disable;
2514 
2515 			_notifier_call_chain(rdev, REGULATOR_EVENT_ENABLE,
2516 					     NULL);
2517 		} else if (ret < 0) {
2518 			rdev_err(rdev, "is_enabled() failed: %d\n", ret);
2519 			goto err_consumer_disable;
2520 		}
2521 		/* Fallthrough on positive return values - already enabled */
2522 	}
2523 
2524 	rdev->use_count++;
2525 
2526 	return 0;
2527 
2528 err_consumer_disable:
2529 	_regulator_handle_consumer_disable(regulator);
2530 
2531 err_disable_supply:
2532 	if (rdev->use_count == 0 && rdev->supply)
2533 		_regulator_disable(rdev->supply);
2534 
2535 	return ret;
2536 }
2537 
2538 /**
2539  * regulator_enable - enable regulator output
2540  * @regulator: regulator source
2541  *
2542  * Request that the regulator be enabled with the regulator output at
2543  * the predefined voltage or current value.  Calls to regulator_enable()
2544  * must be balanced with calls to regulator_disable().
2545  *
2546  * NOTE: the output value can be set by other drivers, boot loader or may be
2547  * hardwired in the regulator.
2548  */
2549 int regulator_enable(struct regulator *regulator)
2550 {
2551 	struct regulator_dev *rdev = regulator->rdev;
2552 	struct ww_acquire_ctx ww_ctx;
2553 	int ret;
2554 
2555 	regulator_lock_dependent(rdev, &ww_ctx);
2556 	ret = _regulator_enable(regulator);
2557 	regulator_unlock_dependent(rdev, &ww_ctx);
2558 
2559 	return ret;
2560 }
2561 EXPORT_SYMBOL_GPL(regulator_enable);
2562 
2563 static int _regulator_do_disable(struct regulator_dev *rdev)
2564 {
2565 	int ret;
2566 
2567 	trace_regulator_disable(rdev_get_name(rdev));
2568 
2569 	if (rdev->ena_pin) {
2570 		if (rdev->ena_gpio_state) {
2571 			ret = regulator_ena_gpio_ctrl(rdev, false);
2572 			if (ret < 0)
2573 				return ret;
2574 			rdev->ena_gpio_state = 0;
2575 		}
2576 
2577 	} else if (rdev->desc->ops->disable) {
2578 		ret = rdev->desc->ops->disable(rdev);
2579 		if (ret != 0)
2580 			return ret;
2581 	}
2582 
2583 	/* cares about last_off_jiffy only if off_on_delay is required by
2584 	 * device.
2585 	 */
2586 	if (rdev->desc->off_on_delay)
2587 		rdev->last_off_jiffy = jiffies;
2588 
2589 	trace_regulator_disable_complete(rdev_get_name(rdev));
2590 
2591 	return 0;
2592 }
2593 
2594 /* locks held by regulator_disable() */
2595 static int _regulator_disable(struct regulator *regulator)
2596 {
2597 	struct regulator_dev *rdev = regulator->rdev;
2598 	int ret = 0;
2599 
2600 	lockdep_assert_held_once(&rdev->mutex.base);
2601 
2602 	if (WARN(rdev->use_count <= 0,
2603 		 "unbalanced disables for %s\n", rdev_get_name(rdev)))
2604 		return -EIO;
2605 
2606 	/* are we the last user and permitted to disable ? */
2607 	if (rdev->use_count == 1 &&
2608 	    (rdev->constraints && !rdev->constraints->always_on)) {
2609 
2610 		/* we are last user */
2611 		if (regulator_ops_is_valid(rdev, REGULATOR_CHANGE_STATUS)) {
2612 			ret = _notifier_call_chain(rdev,
2613 						   REGULATOR_EVENT_PRE_DISABLE,
2614 						   NULL);
2615 			if (ret & NOTIFY_STOP_MASK)
2616 				return -EINVAL;
2617 
2618 			ret = _regulator_do_disable(rdev);
2619 			if (ret < 0) {
2620 				rdev_err(rdev, "failed to disable\n");
2621 				_notifier_call_chain(rdev,
2622 						REGULATOR_EVENT_ABORT_DISABLE,
2623 						NULL);
2624 				return ret;
2625 			}
2626 			_notifier_call_chain(rdev, REGULATOR_EVENT_DISABLE,
2627 					NULL);
2628 		}
2629 
2630 		rdev->use_count = 0;
2631 	} else if (rdev->use_count > 1) {
2632 		rdev->use_count--;
2633 	}
2634 
2635 	if (ret == 0)
2636 		ret = _regulator_handle_consumer_disable(regulator);
2637 
2638 	if (ret == 0 && rdev->coupling_desc.n_coupled > 1)
2639 		ret = regulator_balance_voltage(rdev, PM_SUSPEND_ON);
2640 
2641 	if (ret == 0 && rdev->use_count == 0 && rdev->supply)
2642 		ret = _regulator_disable(rdev->supply);
2643 
2644 	return ret;
2645 }
2646 
2647 /**
2648  * regulator_disable - disable regulator output
2649  * @regulator: regulator source
2650  *
2651  * Disable the regulator output voltage or current.  Calls to
2652  * regulator_enable() must be balanced with calls to
2653  * regulator_disable().
2654  *
2655  * NOTE: this will only disable the regulator output if no other consumer
2656  * devices have it enabled, the regulator device supports disabling and
2657  * machine constraints permit this operation.
2658  */
2659 int regulator_disable(struct regulator *regulator)
2660 {
2661 	struct regulator_dev *rdev = regulator->rdev;
2662 	struct ww_acquire_ctx ww_ctx;
2663 	int ret;
2664 
2665 	regulator_lock_dependent(rdev, &ww_ctx);
2666 	ret = _regulator_disable(regulator);
2667 	regulator_unlock_dependent(rdev, &ww_ctx);
2668 
2669 	return ret;
2670 }
2671 EXPORT_SYMBOL_GPL(regulator_disable);
2672 
2673 /* locks held by regulator_force_disable() */
2674 static int _regulator_force_disable(struct regulator_dev *rdev)
2675 {
2676 	int ret = 0;
2677 
2678 	lockdep_assert_held_once(&rdev->mutex.base);
2679 
2680 	ret = _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
2681 			REGULATOR_EVENT_PRE_DISABLE, NULL);
2682 	if (ret & NOTIFY_STOP_MASK)
2683 		return -EINVAL;
2684 
2685 	ret = _regulator_do_disable(rdev);
2686 	if (ret < 0) {
2687 		rdev_err(rdev, "failed to force disable\n");
2688 		_notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
2689 				REGULATOR_EVENT_ABORT_DISABLE, NULL);
2690 		return ret;
2691 	}
2692 
2693 	_notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
2694 			REGULATOR_EVENT_DISABLE, NULL);
2695 
2696 	return 0;
2697 }
2698 
2699 /**
2700  * regulator_force_disable - force disable regulator output
2701  * @regulator: regulator source
2702  *
2703  * Forcibly disable the regulator output voltage or current.
2704  * NOTE: this *will* disable the regulator output even if other consumer
2705  * devices have it enabled. This should be used for situations when device
2706  * damage will likely occur if the regulator is not disabled (e.g. over temp).
2707  */
2708 int regulator_force_disable(struct regulator *regulator)
2709 {
2710 	struct regulator_dev *rdev = regulator->rdev;
2711 	struct ww_acquire_ctx ww_ctx;
2712 	int ret;
2713 
2714 	regulator_lock_dependent(rdev, &ww_ctx);
2715 
2716 	ret = _regulator_force_disable(regulator->rdev);
2717 
2718 	if (rdev->coupling_desc.n_coupled > 1)
2719 		regulator_balance_voltage(rdev, PM_SUSPEND_ON);
2720 
2721 	if (regulator->uA_load) {
2722 		regulator->uA_load = 0;
2723 		ret = drms_uA_update(rdev);
2724 	}
2725 
2726 	if (rdev->use_count != 0 && rdev->supply)
2727 		_regulator_disable(rdev->supply);
2728 
2729 	regulator_unlock_dependent(rdev, &ww_ctx);
2730 
2731 	return ret;
2732 }
2733 EXPORT_SYMBOL_GPL(regulator_force_disable);
2734 
2735 static void regulator_disable_work(struct work_struct *work)
2736 {
2737 	struct regulator_dev *rdev = container_of(work, struct regulator_dev,
2738 						  disable_work.work);
2739 	struct ww_acquire_ctx ww_ctx;
2740 	int count, i, ret;
2741 	struct regulator *regulator;
2742 	int total_count = 0;
2743 
2744 	regulator_lock_dependent(rdev, &ww_ctx);
2745 
2746 	/*
2747 	 * Workqueue functions queue the new work instance while the previous
2748 	 * work instance is being processed. Cancel the queued work instance
2749 	 * as the work instance under processing does the job of the queued
2750 	 * work instance.
2751 	 */
2752 	cancel_delayed_work(&rdev->disable_work);
2753 
2754 	list_for_each_entry(regulator, &rdev->consumer_list, list) {
2755 		count = regulator->deferred_disables;
2756 
2757 		if (!count)
2758 			continue;
2759 
2760 		total_count += count;
2761 		regulator->deferred_disables = 0;
2762 
2763 		for (i = 0; i < count; i++) {
2764 			ret = _regulator_disable(regulator);
2765 			if (ret != 0)
2766 				rdev_err(rdev, "Deferred disable failed: %d\n", ret);
2767 		}
2768 	}
2769 	WARN_ON(!total_count);
2770 
2771 	if (rdev->coupling_desc.n_coupled > 1)
2772 		regulator_balance_voltage(rdev, PM_SUSPEND_ON);
2773 
2774 	regulator_unlock_dependent(rdev, &ww_ctx);
2775 }
2776 
2777 /**
2778  * regulator_disable_deferred - disable regulator output with delay
2779  * @regulator: regulator source
2780  * @ms: milliseconds until the regulator is disabled
2781  *
2782  * Execute regulator_disable() on the regulator after a delay.  This
2783  * is intended for use with devices that require some time to quiesce.
2784  *
2785  * NOTE: this will only disable the regulator output if no other consumer
2786  * devices have it enabled, the regulator device supports disabling and
2787  * machine constraints permit this operation.
2788  */
2789 int regulator_disable_deferred(struct regulator *regulator, int ms)
2790 {
2791 	struct regulator_dev *rdev = regulator->rdev;
2792 
2793 	if (!ms)
2794 		return regulator_disable(regulator);
2795 
2796 	regulator_lock(rdev);
2797 	regulator->deferred_disables++;
2798 	mod_delayed_work(system_power_efficient_wq, &rdev->disable_work,
2799 			 msecs_to_jiffies(ms));
2800 	regulator_unlock(rdev);
2801 
2802 	return 0;
2803 }
2804 EXPORT_SYMBOL_GPL(regulator_disable_deferred);
2805 
2806 static int _regulator_is_enabled(struct regulator_dev *rdev)
2807 {
2808 	/* A GPIO control always takes precedence */
2809 	if (rdev->ena_pin)
2810 		return rdev->ena_gpio_state;
2811 
2812 	/* If we don't know then assume that the regulator is always on */
2813 	if (!rdev->desc->ops->is_enabled)
2814 		return 1;
2815 
2816 	return rdev->desc->ops->is_enabled(rdev);
2817 }
2818 
2819 static int _regulator_list_voltage(struct regulator_dev *rdev,
2820 				   unsigned selector, int lock)
2821 {
2822 	const struct regulator_ops *ops = rdev->desc->ops;
2823 	int ret;
2824 
2825 	if (rdev->desc->fixed_uV && rdev->desc->n_voltages == 1 && !selector)
2826 		return rdev->desc->fixed_uV;
2827 
2828 	if (ops->list_voltage) {
2829 		if (selector >= rdev->desc->n_voltages)
2830 			return -EINVAL;
2831 		if (lock)
2832 			regulator_lock(rdev);
2833 		ret = ops->list_voltage(rdev, selector);
2834 		if (lock)
2835 			regulator_unlock(rdev);
2836 	} else if (rdev->is_switch && rdev->supply) {
2837 		ret = _regulator_list_voltage(rdev->supply->rdev,
2838 					      selector, lock);
2839 	} else {
2840 		return -EINVAL;
2841 	}
2842 
2843 	if (ret > 0) {
2844 		if (ret < rdev->constraints->min_uV)
2845 			ret = 0;
2846 		else if (ret > rdev->constraints->max_uV)
2847 			ret = 0;
2848 	}
2849 
2850 	return ret;
2851 }
2852 
2853 /**
2854  * regulator_is_enabled - is the regulator output enabled
2855  * @regulator: regulator source
2856  *
2857  * Returns positive if the regulator driver backing the source/client
2858  * has requested that the device be enabled, zero if it hasn't, else a
2859  * negative errno code.
2860  *
2861  * Note that the device backing this regulator handle can have multiple
2862  * users, so it might be enabled even if regulator_enable() was never
2863  * called for this particular source.
2864  */
2865 int regulator_is_enabled(struct regulator *regulator)
2866 {
2867 	int ret;
2868 
2869 	if (regulator->always_on)
2870 		return 1;
2871 
2872 	regulator_lock(regulator->rdev);
2873 	ret = _regulator_is_enabled(regulator->rdev);
2874 	regulator_unlock(regulator->rdev);
2875 
2876 	return ret;
2877 }
2878 EXPORT_SYMBOL_GPL(regulator_is_enabled);
2879 
2880 /**
2881  * regulator_count_voltages - count regulator_list_voltage() selectors
2882  * @regulator: regulator source
2883  *
2884  * Returns number of selectors, or negative errno.  Selectors are
2885  * numbered starting at zero, and typically correspond to bitfields
2886  * in hardware registers.
2887  */
2888 int regulator_count_voltages(struct regulator *regulator)
2889 {
2890 	struct regulator_dev	*rdev = regulator->rdev;
2891 
2892 	if (rdev->desc->n_voltages)
2893 		return rdev->desc->n_voltages;
2894 
2895 	if (!rdev->is_switch || !rdev->supply)
2896 		return -EINVAL;
2897 
2898 	return regulator_count_voltages(rdev->supply);
2899 }
2900 EXPORT_SYMBOL_GPL(regulator_count_voltages);
2901 
2902 /**
2903  * regulator_list_voltage - enumerate supported voltages
2904  * @regulator: regulator source
2905  * @selector: identify voltage to list
2906  * Context: can sleep
2907  *
2908  * Returns a voltage that can be passed to @regulator_set_voltage(),
2909  * zero if this selector code can't be used on this system, or a
2910  * negative errno.
2911  */
2912 int regulator_list_voltage(struct regulator *regulator, unsigned selector)
2913 {
2914 	return _regulator_list_voltage(regulator->rdev, selector, 1);
2915 }
2916 EXPORT_SYMBOL_GPL(regulator_list_voltage);
2917 
2918 /**
2919  * regulator_get_regmap - get the regulator's register map
2920  * @regulator: regulator source
2921  *
2922  * Returns the register map for the given regulator, or an ERR_PTR value
2923  * if the regulator doesn't use regmap.
2924  */
2925 struct regmap *regulator_get_regmap(struct regulator *regulator)
2926 {
2927 	struct regmap *map = regulator->rdev->regmap;
2928 
2929 	return map ? map : ERR_PTR(-EOPNOTSUPP);
2930 }
2931 
2932 /**
2933  * regulator_get_hardware_vsel_register - get the HW voltage selector register
2934  * @regulator: regulator source
2935  * @vsel_reg: voltage selector register, output parameter
2936  * @vsel_mask: mask for voltage selector bitfield, output parameter
2937  *
2938  * Returns the hardware register offset and bitmask used for setting the
2939  * regulator voltage. This might be useful when configuring voltage-scaling
2940  * hardware or firmware that can make I2C requests behind the kernel's back,
2941  * for example.
2942  *
2943  * On success, the output parameters @vsel_reg and @vsel_mask are filled in
2944  * and 0 is returned, otherwise a negative errno is returned.
2945  */
2946 int regulator_get_hardware_vsel_register(struct regulator *regulator,
2947 					 unsigned *vsel_reg,
2948 					 unsigned *vsel_mask)
2949 {
2950 	struct regulator_dev *rdev = regulator->rdev;
2951 	const struct regulator_ops *ops = rdev->desc->ops;
2952 
2953 	if (ops->set_voltage_sel != regulator_set_voltage_sel_regmap)
2954 		return -EOPNOTSUPP;
2955 
2956 	*vsel_reg = rdev->desc->vsel_reg;
2957 	*vsel_mask = rdev->desc->vsel_mask;
2958 
2959 	 return 0;
2960 }
2961 EXPORT_SYMBOL_GPL(regulator_get_hardware_vsel_register);
2962 
2963 /**
2964  * regulator_list_hardware_vsel - get the HW-specific register value for a selector
2965  * @regulator: regulator source
2966  * @selector: identify voltage to list
2967  *
2968  * Converts the selector to a hardware-specific voltage selector that can be
2969  * directly written to the regulator registers. The address of the voltage
2970  * register can be determined by calling @regulator_get_hardware_vsel_register.
2971  *
2972  * On error a negative errno is returned.
2973  */
2974 int regulator_list_hardware_vsel(struct regulator *regulator,
2975 				 unsigned selector)
2976 {
2977 	struct regulator_dev *rdev = regulator->rdev;
2978 	const struct regulator_ops *ops = rdev->desc->ops;
2979 
2980 	if (selector >= rdev->desc->n_voltages)
2981 		return -EINVAL;
2982 	if (ops->set_voltage_sel != regulator_set_voltage_sel_regmap)
2983 		return -EOPNOTSUPP;
2984 
2985 	return selector;
2986 }
2987 EXPORT_SYMBOL_GPL(regulator_list_hardware_vsel);
2988 
2989 /**
2990  * regulator_get_linear_step - return the voltage step size between VSEL values
2991  * @regulator: regulator source
2992  *
2993  * Returns the voltage step size between VSEL values for linear
2994  * regulators, or return 0 if the regulator isn't a linear regulator.
2995  */
2996 unsigned int regulator_get_linear_step(struct regulator *regulator)
2997 {
2998 	struct regulator_dev *rdev = regulator->rdev;
2999 
3000 	return rdev->desc->uV_step;
3001 }
3002 EXPORT_SYMBOL_GPL(regulator_get_linear_step);
3003 
3004 /**
3005  * regulator_is_supported_voltage - check if a voltage range can be supported
3006  *
3007  * @regulator: Regulator to check.
3008  * @min_uV: Minimum required voltage in uV.
3009  * @max_uV: Maximum required voltage in uV.
3010  *
3011  * Returns a boolean.
3012  */
3013 int regulator_is_supported_voltage(struct regulator *regulator,
3014 				   int min_uV, int max_uV)
3015 {
3016 	struct regulator_dev *rdev = regulator->rdev;
3017 	int i, voltages, ret;
3018 
3019 	/* If we can't change voltage check the current voltage */
3020 	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE)) {
3021 		ret = regulator_get_voltage(regulator);
3022 		if (ret >= 0)
3023 			return min_uV <= ret && ret <= max_uV;
3024 		else
3025 			return ret;
3026 	}
3027 
3028 	/* Any voltage within constrains range is fine? */
3029 	if (rdev->desc->continuous_voltage_range)
3030 		return min_uV >= rdev->constraints->min_uV &&
3031 				max_uV <= rdev->constraints->max_uV;
3032 
3033 	ret = regulator_count_voltages(regulator);
3034 	if (ret < 0)
3035 		return 0;
3036 	voltages = ret;
3037 
3038 	for (i = 0; i < voltages; i++) {
3039 		ret = regulator_list_voltage(regulator, i);
3040 
3041 		if (ret >= min_uV && ret <= max_uV)
3042 			return 1;
3043 	}
3044 
3045 	return 0;
3046 }
3047 EXPORT_SYMBOL_GPL(regulator_is_supported_voltage);
3048 
3049 static int regulator_map_voltage(struct regulator_dev *rdev, int min_uV,
3050 				 int max_uV)
3051 {
3052 	const struct regulator_desc *desc = rdev->desc;
3053 
3054 	if (desc->ops->map_voltage)
3055 		return desc->ops->map_voltage(rdev, min_uV, max_uV);
3056 
3057 	if (desc->ops->list_voltage == regulator_list_voltage_linear)
3058 		return regulator_map_voltage_linear(rdev, min_uV, max_uV);
3059 
3060 	if (desc->ops->list_voltage == regulator_list_voltage_linear_range)
3061 		return regulator_map_voltage_linear_range(rdev, min_uV, max_uV);
3062 
3063 	if (desc->ops->list_voltage ==
3064 		regulator_list_voltage_pickable_linear_range)
3065 		return regulator_map_voltage_pickable_linear_range(rdev,
3066 							min_uV, max_uV);
3067 
3068 	return regulator_map_voltage_iterate(rdev, min_uV, max_uV);
3069 }
3070 
3071 static int _regulator_call_set_voltage(struct regulator_dev *rdev,
3072 				       int min_uV, int max_uV,
3073 				       unsigned *selector)
3074 {
3075 	struct pre_voltage_change_data data;
3076 	int ret;
3077 
3078 	data.old_uV = regulator_get_voltage_rdev(rdev);
3079 	data.min_uV = min_uV;
3080 	data.max_uV = max_uV;
3081 	ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE,
3082 				   &data);
3083 	if (ret & NOTIFY_STOP_MASK)
3084 		return -EINVAL;
3085 
3086 	ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV, selector);
3087 	if (ret >= 0)
3088 		return ret;
3089 
3090 	_notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE,
3091 			     (void *)data.old_uV);
3092 
3093 	return ret;
3094 }
3095 
3096 static int _regulator_call_set_voltage_sel(struct regulator_dev *rdev,
3097 					   int uV, unsigned selector)
3098 {
3099 	struct pre_voltage_change_data data;
3100 	int ret;
3101 
3102 	data.old_uV = regulator_get_voltage_rdev(rdev);
3103 	data.min_uV = uV;
3104 	data.max_uV = uV;
3105 	ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE,
3106 				   &data);
3107 	if (ret & NOTIFY_STOP_MASK)
3108 		return -EINVAL;
3109 
3110 	ret = rdev->desc->ops->set_voltage_sel(rdev, selector);
3111 	if (ret >= 0)
3112 		return ret;
3113 
3114 	_notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE,
3115 			     (void *)data.old_uV);
3116 
3117 	return ret;
3118 }
3119 
3120 static int _regulator_set_voltage_sel_step(struct regulator_dev *rdev,
3121 					   int uV, int new_selector)
3122 {
3123 	const struct regulator_ops *ops = rdev->desc->ops;
3124 	int diff, old_sel, curr_sel, ret;
3125 
3126 	/* Stepping is only needed if the regulator is enabled. */
3127 	if (!_regulator_is_enabled(rdev))
3128 		goto final_set;
3129 
3130 	if (!ops->get_voltage_sel)
3131 		return -EINVAL;
3132 
3133 	old_sel = ops->get_voltage_sel(rdev);
3134 	if (old_sel < 0)
3135 		return old_sel;
3136 
3137 	diff = new_selector - old_sel;
3138 	if (diff == 0)
3139 		return 0; /* No change needed. */
3140 
3141 	if (diff > 0) {
3142 		/* Stepping up. */
3143 		for (curr_sel = old_sel + rdev->desc->vsel_step;
3144 		     curr_sel < new_selector;
3145 		     curr_sel += rdev->desc->vsel_step) {
3146 			/*
3147 			 * Call the callback directly instead of using
3148 			 * _regulator_call_set_voltage_sel() as we don't
3149 			 * want to notify anyone yet. Same in the branch
3150 			 * below.
3151 			 */
3152 			ret = ops->set_voltage_sel(rdev, curr_sel);
3153 			if (ret)
3154 				goto try_revert;
3155 		}
3156 	} else {
3157 		/* Stepping down. */
3158 		for (curr_sel = old_sel - rdev->desc->vsel_step;
3159 		     curr_sel > new_selector;
3160 		     curr_sel -= rdev->desc->vsel_step) {
3161 			ret = ops->set_voltage_sel(rdev, curr_sel);
3162 			if (ret)
3163 				goto try_revert;
3164 		}
3165 	}
3166 
3167 final_set:
3168 	/* The final selector will trigger the notifiers. */
3169 	return _regulator_call_set_voltage_sel(rdev, uV, new_selector);
3170 
3171 try_revert:
3172 	/*
3173 	 * At least try to return to the previous voltage if setting a new
3174 	 * one failed.
3175 	 */
3176 	(void)ops->set_voltage_sel(rdev, old_sel);
3177 	return ret;
3178 }
3179 
3180 static int _regulator_set_voltage_time(struct regulator_dev *rdev,
3181 				       int old_uV, int new_uV)
3182 {
3183 	unsigned int ramp_delay = 0;
3184 
3185 	if (rdev->constraints->ramp_delay)
3186 		ramp_delay = rdev->constraints->ramp_delay;
3187 	else if (rdev->desc->ramp_delay)
3188 		ramp_delay = rdev->desc->ramp_delay;
3189 	else if (rdev->constraints->settling_time)
3190 		return rdev->constraints->settling_time;
3191 	else if (rdev->constraints->settling_time_up &&
3192 		 (new_uV > old_uV))
3193 		return rdev->constraints->settling_time_up;
3194 	else if (rdev->constraints->settling_time_down &&
3195 		 (new_uV < old_uV))
3196 		return rdev->constraints->settling_time_down;
3197 
3198 	if (ramp_delay == 0) {
3199 		rdev_dbg(rdev, "ramp_delay not set\n");
3200 		return 0;
3201 	}
3202 
3203 	return DIV_ROUND_UP(abs(new_uV - old_uV), ramp_delay);
3204 }
3205 
3206 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
3207 				     int min_uV, int max_uV)
3208 {
3209 	int ret;
3210 	int delay = 0;
3211 	int best_val = 0;
3212 	unsigned int selector;
3213 	int old_selector = -1;
3214 	const struct regulator_ops *ops = rdev->desc->ops;
3215 	int old_uV = regulator_get_voltage_rdev(rdev);
3216 
3217 	trace_regulator_set_voltage(rdev_get_name(rdev), min_uV, max_uV);
3218 
3219 	min_uV += rdev->constraints->uV_offset;
3220 	max_uV += rdev->constraints->uV_offset;
3221 
3222 	/*
3223 	 * If we can't obtain the old selector there is not enough
3224 	 * info to call set_voltage_time_sel().
3225 	 */
3226 	if (_regulator_is_enabled(rdev) &&
3227 	    ops->set_voltage_time_sel && ops->get_voltage_sel) {
3228 		old_selector = ops->get_voltage_sel(rdev);
3229 		if (old_selector < 0)
3230 			return old_selector;
3231 	}
3232 
3233 	if (ops->set_voltage) {
3234 		ret = _regulator_call_set_voltage(rdev, min_uV, max_uV,
3235 						  &selector);
3236 
3237 		if (ret >= 0) {
3238 			if (ops->list_voltage)
3239 				best_val = ops->list_voltage(rdev,
3240 							     selector);
3241 			else
3242 				best_val = regulator_get_voltage_rdev(rdev);
3243 		}
3244 
3245 	} else if (ops->set_voltage_sel) {
3246 		ret = regulator_map_voltage(rdev, min_uV, max_uV);
3247 		if (ret >= 0) {
3248 			best_val = ops->list_voltage(rdev, ret);
3249 			if (min_uV <= best_val && max_uV >= best_val) {
3250 				selector = ret;
3251 				if (old_selector == selector)
3252 					ret = 0;
3253 				else if (rdev->desc->vsel_step)
3254 					ret = _regulator_set_voltage_sel_step(
3255 						rdev, best_val, selector);
3256 				else
3257 					ret = _regulator_call_set_voltage_sel(
3258 						rdev, best_val, selector);
3259 			} else {
3260 				ret = -EINVAL;
3261 			}
3262 		}
3263 	} else {
3264 		ret = -EINVAL;
3265 	}
3266 
3267 	if (ret)
3268 		goto out;
3269 
3270 	if (ops->set_voltage_time_sel) {
3271 		/*
3272 		 * Call set_voltage_time_sel if successfully obtained
3273 		 * old_selector
3274 		 */
3275 		if (old_selector >= 0 && old_selector != selector)
3276 			delay = ops->set_voltage_time_sel(rdev, old_selector,
3277 							  selector);
3278 	} else {
3279 		if (old_uV != best_val) {
3280 			if (ops->set_voltage_time)
3281 				delay = ops->set_voltage_time(rdev, old_uV,
3282 							      best_val);
3283 			else
3284 				delay = _regulator_set_voltage_time(rdev,
3285 								    old_uV,
3286 								    best_val);
3287 		}
3288 	}
3289 
3290 	if (delay < 0) {
3291 		rdev_warn(rdev, "failed to get delay: %d\n", delay);
3292 		delay = 0;
3293 	}
3294 
3295 	/* Insert any necessary delays */
3296 	if (delay >= 1000) {
3297 		mdelay(delay / 1000);
3298 		udelay(delay % 1000);
3299 	} else if (delay) {
3300 		udelay(delay);
3301 	}
3302 
3303 	if (best_val >= 0) {
3304 		unsigned long data = best_val;
3305 
3306 		_notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE,
3307 				     (void *)data);
3308 	}
3309 
3310 out:
3311 	trace_regulator_set_voltage_complete(rdev_get_name(rdev), best_val);
3312 
3313 	return ret;
3314 }
3315 
3316 static int _regulator_do_set_suspend_voltage(struct regulator_dev *rdev,
3317 				  int min_uV, int max_uV, suspend_state_t state)
3318 {
3319 	struct regulator_state *rstate;
3320 	int uV, sel;
3321 
3322 	rstate = regulator_get_suspend_state(rdev, state);
3323 	if (rstate == NULL)
3324 		return -EINVAL;
3325 
3326 	if (min_uV < rstate->min_uV)
3327 		min_uV = rstate->min_uV;
3328 	if (max_uV > rstate->max_uV)
3329 		max_uV = rstate->max_uV;
3330 
3331 	sel = regulator_map_voltage(rdev, min_uV, max_uV);
3332 	if (sel < 0)
3333 		return sel;
3334 
3335 	uV = rdev->desc->ops->list_voltage(rdev, sel);
3336 	if (uV >= min_uV && uV <= max_uV)
3337 		rstate->uV = uV;
3338 
3339 	return 0;
3340 }
3341 
3342 static int regulator_set_voltage_unlocked(struct regulator *regulator,
3343 					  int min_uV, int max_uV,
3344 					  suspend_state_t state)
3345 {
3346 	struct regulator_dev *rdev = regulator->rdev;
3347 	struct regulator_voltage *voltage = &regulator->voltage[state];
3348 	int ret = 0;
3349 	int old_min_uV, old_max_uV;
3350 	int current_uV;
3351 
3352 	/* If we're setting the same range as last time the change
3353 	 * should be a noop (some cpufreq implementations use the same
3354 	 * voltage for multiple frequencies, for example).
3355 	 */
3356 	if (voltage->min_uV == min_uV && voltage->max_uV == max_uV)
3357 		goto out;
3358 
3359 	/* If we're trying to set a range that overlaps the current voltage,
3360 	 * return successfully even though the regulator does not support
3361 	 * changing the voltage.
3362 	 */
3363 	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE)) {
3364 		current_uV = regulator_get_voltage_rdev(rdev);
3365 		if (min_uV <= current_uV && current_uV <= max_uV) {
3366 			voltage->min_uV = min_uV;
3367 			voltage->max_uV = max_uV;
3368 			goto out;
3369 		}
3370 	}
3371 
3372 	/* sanity check */
3373 	if (!rdev->desc->ops->set_voltage &&
3374 	    !rdev->desc->ops->set_voltage_sel) {
3375 		ret = -EINVAL;
3376 		goto out;
3377 	}
3378 
3379 	/* constraints check */
3380 	ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
3381 	if (ret < 0)
3382 		goto out;
3383 
3384 	/* restore original values in case of error */
3385 	old_min_uV = voltage->min_uV;
3386 	old_max_uV = voltage->max_uV;
3387 	voltage->min_uV = min_uV;
3388 	voltage->max_uV = max_uV;
3389 
3390 	/* for not coupled regulators this will just set the voltage */
3391 	ret = regulator_balance_voltage(rdev, state);
3392 	if (ret < 0) {
3393 		voltage->min_uV = old_min_uV;
3394 		voltage->max_uV = old_max_uV;
3395 	}
3396 
3397 out:
3398 	return ret;
3399 }
3400 
3401 int regulator_set_voltage_rdev(struct regulator_dev *rdev, int min_uV,
3402 			       int max_uV, suspend_state_t state)
3403 {
3404 	int best_supply_uV = 0;
3405 	int supply_change_uV = 0;
3406 	int ret;
3407 
3408 	if (rdev->supply &&
3409 	    regulator_ops_is_valid(rdev->supply->rdev,
3410 				   REGULATOR_CHANGE_VOLTAGE) &&
3411 	    (rdev->desc->min_dropout_uV || !(rdev->desc->ops->get_voltage ||
3412 					   rdev->desc->ops->get_voltage_sel))) {
3413 		int current_supply_uV;
3414 		int selector;
3415 
3416 		selector = regulator_map_voltage(rdev, min_uV, max_uV);
3417 		if (selector < 0) {
3418 			ret = selector;
3419 			goto out;
3420 		}
3421 
3422 		best_supply_uV = _regulator_list_voltage(rdev, selector, 0);
3423 		if (best_supply_uV < 0) {
3424 			ret = best_supply_uV;
3425 			goto out;
3426 		}
3427 
3428 		best_supply_uV += rdev->desc->min_dropout_uV;
3429 
3430 		current_supply_uV = regulator_get_voltage_rdev(rdev->supply->rdev);
3431 		if (current_supply_uV < 0) {
3432 			ret = current_supply_uV;
3433 			goto out;
3434 		}
3435 
3436 		supply_change_uV = best_supply_uV - current_supply_uV;
3437 	}
3438 
3439 	if (supply_change_uV > 0) {
3440 		ret = regulator_set_voltage_unlocked(rdev->supply,
3441 				best_supply_uV, INT_MAX, state);
3442 		if (ret) {
3443 			dev_err(&rdev->dev, "Failed to increase supply voltage: %d\n",
3444 					ret);
3445 			goto out;
3446 		}
3447 	}
3448 
3449 	if (state == PM_SUSPEND_ON)
3450 		ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
3451 	else
3452 		ret = _regulator_do_set_suspend_voltage(rdev, min_uV,
3453 							max_uV, state);
3454 	if (ret < 0)
3455 		goto out;
3456 
3457 	if (supply_change_uV < 0) {
3458 		ret = regulator_set_voltage_unlocked(rdev->supply,
3459 				best_supply_uV, INT_MAX, state);
3460 		if (ret)
3461 			dev_warn(&rdev->dev, "Failed to decrease supply voltage: %d\n",
3462 					ret);
3463 		/* No need to fail here */
3464 		ret = 0;
3465 	}
3466 
3467 out:
3468 	return ret;
3469 }
3470 EXPORT_SYMBOL_GPL(regulator_set_voltage_rdev);
3471 
3472 static int regulator_limit_voltage_step(struct regulator_dev *rdev,
3473 					int *current_uV, int *min_uV)
3474 {
3475 	struct regulation_constraints *constraints = rdev->constraints;
3476 
3477 	/* Limit voltage change only if necessary */
3478 	if (!constraints->max_uV_step || !_regulator_is_enabled(rdev))
3479 		return 1;
3480 
3481 	if (*current_uV < 0) {
3482 		*current_uV = regulator_get_voltage_rdev(rdev);
3483 
3484 		if (*current_uV < 0)
3485 			return *current_uV;
3486 	}
3487 
3488 	if (abs(*current_uV - *min_uV) <= constraints->max_uV_step)
3489 		return 1;
3490 
3491 	/* Clamp target voltage within the given step */
3492 	if (*current_uV < *min_uV)
3493 		*min_uV = min(*current_uV + constraints->max_uV_step,
3494 			      *min_uV);
3495 	else
3496 		*min_uV = max(*current_uV - constraints->max_uV_step,
3497 			      *min_uV);
3498 
3499 	return 0;
3500 }
3501 
3502 static int regulator_get_optimal_voltage(struct regulator_dev *rdev,
3503 					 int *current_uV,
3504 					 int *min_uV, int *max_uV,
3505 					 suspend_state_t state,
3506 					 int n_coupled)
3507 {
3508 	struct coupling_desc *c_desc = &rdev->coupling_desc;
3509 	struct regulator_dev **c_rdevs = c_desc->coupled_rdevs;
3510 	struct regulation_constraints *constraints = rdev->constraints;
3511 	int desired_min_uV = 0, desired_max_uV = INT_MAX;
3512 	int max_current_uV = 0, min_current_uV = INT_MAX;
3513 	int highest_min_uV = 0, target_uV, possible_uV;
3514 	int i, ret, max_spread;
3515 	bool done;
3516 
3517 	*current_uV = -1;
3518 
3519 	/*
3520 	 * If there are no coupled regulators, simply set the voltage
3521 	 * demanded by consumers.
3522 	 */
3523 	if (n_coupled == 1) {
3524 		/*
3525 		 * If consumers don't provide any demands, set voltage
3526 		 * to min_uV
3527 		 */
3528 		desired_min_uV = constraints->min_uV;
3529 		desired_max_uV = constraints->max_uV;
3530 
3531 		ret = regulator_check_consumers(rdev,
3532 						&desired_min_uV,
3533 						&desired_max_uV, state);
3534 		if (ret < 0)
3535 			return ret;
3536 
3537 		possible_uV = desired_min_uV;
3538 		done = true;
3539 
3540 		goto finish;
3541 	}
3542 
3543 	/* Find highest min desired voltage */
3544 	for (i = 0; i < n_coupled; i++) {
3545 		int tmp_min = 0;
3546 		int tmp_max = INT_MAX;
3547 
3548 		lockdep_assert_held_once(&c_rdevs[i]->mutex.base);
3549 
3550 		ret = regulator_check_consumers(c_rdevs[i],
3551 						&tmp_min,
3552 						&tmp_max, state);
3553 		if (ret < 0)
3554 			return ret;
3555 
3556 		ret = regulator_check_voltage(c_rdevs[i], &tmp_min, &tmp_max);
3557 		if (ret < 0)
3558 			return ret;
3559 
3560 		highest_min_uV = max(highest_min_uV, tmp_min);
3561 
3562 		if (i == 0) {
3563 			desired_min_uV = tmp_min;
3564 			desired_max_uV = tmp_max;
3565 		}
3566 	}
3567 
3568 	max_spread = constraints->max_spread[0];
3569 
3570 	/*
3571 	 * Let target_uV be equal to the desired one if possible.
3572 	 * If not, set it to minimum voltage, allowed by other coupled
3573 	 * regulators.
3574 	 */
3575 	target_uV = max(desired_min_uV, highest_min_uV - max_spread);
3576 
3577 	/*
3578 	 * Find min and max voltages, which currently aren't violating
3579 	 * max_spread.
3580 	 */
3581 	for (i = 1; i < n_coupled; i++) {
3582 		int tmp_act;
3583 
3584 		if (!_regulator_is_enabled(c_rdevs[i]))
3585 			continue;
3586 
3587 		tmp_act = regulator_get_voltage_rdev(c_rdevs[i]);
3588 		if (tmp_act < 0)
3589 			return tmp_act;
3590 
3591 		min_current_uV = min(tmp_act, min_current_uV);
3592 		max_current_uV = max(tmp_act, max_current_uV);
3593 	}
3594 
3595 	/* There aren't any other regulators enabled */
3596 	if (max_current_uV == 0) {
3597 		possible_uV = target_uV;
3598 	} else {
3599 		/*
3600 		 * Correct target voltage, so as it currently isn't
3601 		 * violating max_spread
3602 		 */
3603 		possible_uV = max(target_uV, max_current_uV - max_spread);
3604 		possible_uV = min(possible_uV, min_current_uV + max_spread);
3605 	}
3606 
3607 	if (possible_uV > desired_max_uV)
3608 		return -EINVAL;
3609 
3610 	done = (possible_uV == target_uV);
3611 	desired_min_uV = possible_uV;
3612 
3613 finish:
3614 	/* Apply max_uV_step constraint if necessary */
3615 	if (state == PM_SUSPEND_ON) {
3616 		ret = regulator_limit_voltage_step(rdev, current_uV,
3617 						   &desired_min_uV);
3618 		if (ret < 0)
3619 			return ret;
3620 
3621 		if (ret == 0)
3622 			done = false;
3623 	}
3624 
3625 	/* Set current_uV if wasn't done earlier in the code and if necessary */
3626 	if (n_coupled > 1 && *current_uV == -1) {
3627 
3628 		if (_regulator_is_enabled(rdev)) {
3629 			ret = regulator_get_voltage_rdev(rdev);
3630 			if (ret < 0)
3631 				return ret;
3632 
3633 			*current_uV = ret;
3634 		} else {
3635 			*current_uV = desired_min_uV;
3636 		}
3637 	}
3638 
3639 	*min_uV = desired_min_uV;
3640 	*max_uV = desired_max_uV;
3641 
3642 	return done;
3643 }
3644 
3645 int regulator_do_balance_voltage(struct regulator_dev *rdev,
3646 				 suspend_state_t state, bool skip_coupled)
3647 {
3648 	struct regulator_dev **c_rdevs;
3649 	struct regulator_dev *best_rdev;
3650 	struct coupling_desc *c_desc = &rdev->coupling_desc;
3651 	int i, ret, n_coupled, best_min_uV, best_max_uV, best_c_rdev;
3652 	unsigned int delta, best_delta;
3653 	unsigned long c_rdev_done = 0;
3654 	bool best_c_rdev_done;
3655 
3656 	c_rdevs = c_desc->coupled_rdevs;
3657 	n_coupled = skip_coupled ? 1 : c_desc->n_coupled;
3658 
3659 	/*
3660 	 * Find the best possible voltage change on each loop. Leave the loop
3661 	 * if there isn't any possible change.
3662 	 */
3663 	do {
3664 		best_c_rdev_done = false;
3665 		best_delta = 0;
3666 		best_min_uV = 0;
3667 		best_max_uV = 0;
3668 		best_c_rdev = 0;
3669 		best_rdev = NULL;
3670 
3671 		/*
3672 		 * Find highest difference between optimal voltage
3673 		 * and current voltage.
3674 		 */
3675 		for (i = 0; i < n_coupled; i++) {
3676 			/*
3677 			 * optimal_uV is the best voltage that can be set for
3678 			 * i-th regulator at the moment without violating
3679 			 * max_spread constraint in order to balance
3680 			 * the coupled voltages.
3681 			 */
3682 			int optimal_uV = 0, optimal_max_uV = 0, current_uV = 0;
3683 
3684 			if (test_bit(i, &c_rdev_done))
3685 				continue;
3686 
3687 			ret = regulator_get_optimal_voltage(c_rdevs[i],
3688 							    &current_uV,
3689 							    &optimal_uV,
3690 							    &optimal_max_uV,
3691 							    state, n_coupled);
3692 			if (ret < 0)
3693 				goto out;
3694 
3695 			delta = abs(optimal_uV - current_uV);
3696 
3697 			if (delta && best_delta <= delta) {
3698 				best_c_rdev_done = ret;
3699 				best_delta = delta;
3700 				best_rdev = c_rdevs[i];
3701 				best_min_uV = optimal_uV;
3702 				best_max_uV = optimal_max_uV;
3703 				best_c_rdev = i;
3704 			}
3705 		}
3706 
3707 		/* Nothing to change, return successfully */
3708 		if (!best_rdev) {
3709 			ret = 0;
3710 			goto out;
3711 		}
3712 
3713 		ret = regulator_set_voltage_rdev(best_rdev, best_min_uV,
3714 						 best_max_uV, state);
3715 
3716 		if (ret < 0)
3717 			goto out;
3718 
3719 		if (best_c_rdev_done)
3720 			set_bit(best_c_rdev, &c_rdev_done);
3721 
3722 	} while (n_coupled > 1);
3723 
3724 out:
3725 	return ret;
3726 }
3727 
3728 static int regulator_balance_voltage(struct regulator_dev *rdev,
3729 				     suspend_state_t state)
3730 {
3731 	struct coupling_desc *c_desc = &rdev->coupling_desc;
3732 	struct regulator_coupler *coupler = c_desc->coupler;
3733 	bool skip_coupled = false;
3734 
3735 	/*
3736 	 * If system is in a state other than PM_SUSPEND_ON, don't check
3737 	 * other coupled regulators.
3738 	 */
3739 	if (state != PM_SUSPEND_ON)
3740 		skip_coupled = true;
3741 
3742 	if (c_desc->n_resolved < c_desc->n_coupled) {
3743 		rdev_err(rdev, "Not all coupled regulators registered\n");
3744 		return -EPERM;
3745 	}
3746 
3747 	/* Invoke custom balancer for customized couplers */
3748 	if (coupler && coupler->balance_voltage)
3749 		return coupler->balance_voltage(coupler, rdev, state);
3750 
3751 	return regulator_do_balance_voltage(rdev, state, skip_coupled);
3752 }
3753 
3754 /**
3755  * regulator_set_voltage - set regulator output voltage
3756  * @regulator: regulator source
3757  * @min_uV: Minimum required voltage in uV
3758  * @max_uV: Maximum acceptable voltage in uV
3759  *
3760  * Sets a voltage regulator to the desired output voltage. This can be set
3761  * during any regulator state. IOW, regulator can be disabled or enabled.
3762  *
3763  * If the regulator is enabled then the voltage will change to the new value
3764  * immediately otherwise if the regulator is disabled the regulator will
3765  * output at the new voltage when enabled.
3766  *
3767  * NOTE: If the regulator is shared between several devices then the lowest
3768  * request voltage that meets the system constraints will be used.
3769  * Regulator system constraints must be set for this regulator before
3770  * calling this function otherwise this call will fail.
3771  */
3772 int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
3773 {
3774 	struct ww_acquire_ctx ww_ctx;
3775 	int ret;
3776 
3777 	regulator_lock_dependent(regulator->rdev, &ww_ctx);
3778 
3779 	ret = regulator_set_voltage_unlocked(regulator, min_uV, max_uV,
3780 					     PM_SUSPEND_ON);
3781 
3782 	regulator_unlock_dependent(regulator->rdev, &ww_ctx);
3783 
3784 	return ret;
3785 }
3786 EXPORT_SYMBOL_GPL(regulator_set_voltage);
3787 
3788 static inline int regulator_suspend_toggle(struct regulator_dev *rdev,
3789 					   suspend_state_t state, bool en)
3790 {
3791 	struct regulator_state *rstate;
3792 
3793 	rstate = regulator_get_suspend_state(rdev, state);
3794 	if (rstate == NULL)
3795 		return -EINVAL;
3796 
3797 	if (!rstate->changeable)
3798 		return -EPERM;
3799 
3800 	rstate->enabled = (en) ? ENABLE_IN_SUSPEND : DISABLE_IN_SUSPEND;
3801 
3802 	return 0;
3803 }
3804 
3805 int regulator_suspend_enable(struct regulator_dev *rdev,
3806 				    suspend_state_t state)
3807 {
3808 	return regulator_suspend_toggle(rdev, state, true);
3809 }
3810 EXPORT_SYMBOL_GPL(regulator_suspend_enable);
3811 
3812 int regulator_suspend_disable(struct regulator_dev *rdev,
3813 				     suspend_state_t state)
3814 {
3815 	struct regulator *regulator;
3816 	struct regulator_voltage *voltage;
3817 
3818 	/*
3819 	 * if any consumer wants this regulator device keeping on in
3820 	 * suspend states, don't set it as disabled.
3821 	 */
3822 	list_for_each_entry(regulator, &rdev->consumer_list, list) {
3823 		voltage = &regulator->voltage[state];
3824 		if (voltage->min_uV || voltage->max_uV)
3825 			return 0;
3826 	}
3827 
3828 	return regulator_suspend_toggle(rdev, state, false);
3829 }
3830 EXPORT_SYMBOL_GPL(regulator_suspend_disable);
3831 
3832 static int _regulator_set_suspend_voltage(struct regulator *regulator,
3833 					  int min_uV, int max_uV,
3834 					  suspend_state_t state)
3835 {
3836 	struct regulator_dev *rdev = regulator->rdev;
3837 	struct regulator_state *rstate;
3838 
3839 	rstate = regulator_get_suspend_state(rdev, state);
3840 	if (rstate == NULL)
3841 		return -EINVAL;
3842 
3843 	if (rstate->min_uV == rstate->max_uV) {
3844 		rdev_err(rdev, "The suspend voltage can't be changed!\n");
3845 		return -EPERM;
3846 	}
3847 
3848 	return regulator_set_voltage_unlocked(regulator, min_uV, max_uV, state);
3849 }
3850 
3851 int regulator_set_suspend_voltage(struct regulator *regulator, int min_uV,
3852 				  int max_uV, suspend_state_t state)
3853 {
3854 	struct ww_acquire_ctx ww_ctx;
3855 	int ret;
3856 
3857 	/* PM_SUSPEND_ON is handled by regulator_set_voltage() */
3858 	if (regulator_check_states(state) || state == PM_SUSPEND_ON)
3859 		return -EINVAL;
3860 
3861 	regulator_lock_dependent(regulator->rdev, &ww_ctx);
3862 
3863 	ret = _regulator_set_suspend_voltage(regulator, min_uV,
3864 					     max_uV, state);
3865 
3866 	regulator_unlock_dependent(regulator->rdev, &ww_ctx);
3867 
3868 	return ret;
3869 }
3870 EXPORT_SYMBOL_GPL(regulator_set_suspend_voltage);
3871 
3872 /**
3873  * regulator_set_voltage_time - get raise/fall time
3874  * @regulator: regulator source
3875  * @old_uV: starting voltage in microvolts
3876  * @new_uV: target voltage in microvolts
3877  *
3878  * Provided with the starting and ending voltage, this function attempts to
3879  * calculate the time in microseconds required to rise or fall to this new
3880  * voltage.
3881  */
3882 int regulator_set_voltage_time(struct regulator *regulator,
3883 			       int old_uV, int new_uV)
3884 {
3885 	struct regulator_dev *rdev = regulator->rdev;
3886 	const struct regulator_ops *ops = rdev->desc->ops;
3887 	int old_sel = -1;
3888 	int new_sel = -1;
3889 	int voltage;
3890 	int i;
3891 
3892 	if (ops->set_voltage_time)
3893 		return ops->set_voltage_time(rdev, old_uV, new_uV);
3894 	else if (!ops->set_voltage_time_sel)
3895 		return _regulator_set_voltage_time(rdev, old_uV, new_uV);
3896 
3897 	/* Currently requires operations to do this */
3898 	if (!ops->list_voltage || !rdev->desc->n_voltages)
3899 		return -EINVAL;
3900 
3901 	for (i = 0; i < rdev->desc->n_voltages; i++) {
3902 		/* We only look for exact voltage matches here */
3903 		voltage = regulator_list_voltage(regulator, i);
3904 		if (voltage < 0)
3905 			return -EINVAL;
3906 		if (voltage == 0)
3907 			continue;
3908 		if (voltage == old_uV)
3909 			old_sel = i;
3910 		if (voltage == new_uV)
3911 			new_sel = i;
3912 	}
3913 
3914 	if (old_sel < 0 || new_sel < 0)
3915 		return -EINVAL;
3916 
3917 	return ops->set_voltage_time_sel(rdev, old_sel, new_sel);
3918 }
3919 EXPORT_SYMBOL_GPL(regulator_set_voltage_time);
3920 
3921 /**
3922  * regulator_set_voltage_time_sel - get raise/fall time
3923  * @rdev: regulator source device
3924  * @old_selector: selector for starting voltage
3925  * @new_selector: selector for target voltage
3926  *
3927  * Provided with the starting and target voltage selectors, this function
3928  * returns time in microseconds required to rise or fall to this new voltage
3929  *
3930  * Drivers providing ramp_delay in regulation_constraints can use this as their
3931  * set_voltage_time_sel() operation.
3932  */
3933 int regulator_set_voltage_time_sel(struct regulator_dev *rdev,
3934 				   unsigned int old_selector,
3935 				   unsigned int new_selector)
3936 {
3937 	int old_volt, new_volt;
3938 
3939 	/* sanity check */
3940 	if (!rdev->desc->ops->list_voltage)
3941 		return -EINVAL;
3942 
3943 	old_volt = rdev->desc->ops->list_voltage(rdev, old_selector);
3944 	new_volt = rdev->desc->ops->list_voltage(rdev, new_selector);
3945 
3946 	if (rdev->desc->ops->set_voltage_time)
3947 		return rdev->desc->ops->set_voltage_time(rdev, old_volt,
3948 							 new_volt);
3949 	else
3950 		return _regulator_set_voltage_time(rdev, old_volt, new_volt);
3951 }
3952 EXPORT_SYMBOL_GPL(regulator_set_voltage_time_sel);
3953 
3954 /**
3955  * regulator_sync_voltage - re-apply last regulator output voltage
3956  * @regulator: regulator source
3957  *
3958  * Re-apply the last configured voltage.  This is intended to be used
3959  * where some external control source the consumer is cooperating with
3960  * has caused the configured voltage to change.
3961  */
3962 int regulator_sync_voltage(struct regulator *regulator)
3963 {
3964 	struct regulator_dev *rdev = regulator->rdev;
3965 	struct regulator_voltage *voltage = &regulator->voltage[PM_SUSPEND_ON];
3966 	int ret, min_uV, max_uV;
3967 
3968 	regulator_lock(rdev);
3969 
3970 	if (!rdev->desc->ops->set_voltage &&
3971 	    !rdev->desc->ops->set_voltage_sel) {
3972 		ret = -EINVAL;
3973 		goto out;
3974 	}
3975 
3976 	/* This is only going to work if we've had a voltage configured. */
3977 	if (!voltage->min_uV && !voltage->max_uV) {
3978 		ret = -EINVAL;
3979 		goto out;
3980 	}
3981 
3982 	min_uV = voltage->min_uV;
3983 	max_uV = voltage->max_uV;
3984 
3985 	/* This should be a paranoia check... */
3986 	ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
3987 	if (ret < 0)
3988 		goto out;
3989 
3990 	ret = regulator_check_consumers(rdev, &min_uV, &max_uV, 0);
3991 	if (ret < 0)
3992 		goto out;
3993 
3994 	ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
3995 
3996 out:
3997 	regulator_unlock(rdev);
3998 	return ret;
3999 }
4000 EXPORT_SYMBOL_GPL(regulator_sync_voltage);
4001 
4002 int regulator_get_voltage_rdev(struct regulator_dev *rdev)
4003 {
4004 	int sel, ret;
4005 	bool bypassed;
4006 
4007 	if (rdev->desc->ops->get_bypass) {
4008 		ret = rdev->desc->ops->get_bypass(rdev, &bypassed);
4009 		if (ret < 0)
4010 			return ret;
4011 		if (bypassed) {
4012 			/* if bypassed the regulator must have a supply */
4013 			if (!rdev->supply) {
4014 				rdev_err(rdev,
4015 					 "bypassed regulator has no supply!\n");
4016 				return -EPROBE_DEFER;
4017 			}
4018 
4019 			return regulator_get_voltage_rdev(rdev->supply->rdev);
4020 		}
4021 	}
4022 
4023 	if (rdev->desc->ops->get_voltage_sel) {
4024 		sel = rdev->desc->ops->get_voltage_sel(rdev);
4025 		if (sel < 0)
4026 			return sel;
4027 		ret = rdev->desc->ops->list_voltage(rdev, sel);
4028 	} else if (rdev->desc->ops->get_voltage) {
4029 		ret = rdev->desc->ops->get_voltage(rdev);
4030 	} else if (rdev->desc->ops->list_voltage) {
4031 		ret = rdev->desc->ops->list_voltage(rdev, 0);
4032 	} else if (rdev->desc->fixed_uV && (rdev->desc->n_voltages == 1)) {
4033 		ret = rdev->desc->fixed_uV;
4034 	} else if (rdev->supply) {
4035 		ret = regulator_get_voltage_rdev(rdev->supply->rdev);
4036 	} else {
4037 		return -EINVAL;
4038 	}
4039 
4040 	if (ret < 0)
4041 		return ret;
4042 	return ret - rdev->constraints->uV_offset;
4043 }
4044 EXPORT_SYMBOL_GPL(regulator_get_voltage_rdev);
4045 
4046 /**
4047  * regulator_get_voltage - get regulator output voltage
4048  * @regulator: regulator source
4049  *
4050  * This returns the current regulator voltage in uV.
4051  *
4052  * NOTE: If the regulator is disabled it will return the voltage value. This
4053  * function should not be used to determine regulator state.
4054  */
4055 int regulator_get_voltage(struct regulator *regulator)
4056 {
4057 	struct ww_acquire_ctx ww_ctx;
4058 	int ret;
4059 
4060 	regulator_lock_dependent(regulator->rdev, &ww_ctx);
4061 	ret = regulator_get_voltage_rdev(regulator->rdev);
4062 	regulator_unlock_dependent(regulator->rdev, &ww_ctx);
4063 
4064 	return ret;
4065 }
4066 EXPORT_SYMBOL_GPL(regulator_get_voltage);
4067 
4068 /**
4069  * regulator_set_current_limit - set regulator output current limit
4070  * @regulator: regulator source
4071  * @min_uA: Minimum supported current in uA
4072  * @max_uA: Maximum supported current in uA
4073  *
4074  * Sets current sink to the desired output current. This can be set during
4075  * any regulator state. IOW, regulator can be disabled or enabled.
4076  *
4077  * If the regulator is enabled then the current will change to the new value
4078  * immediately otherwise if the regulator is disabled the regulator will
4079  * output at the new current when enabled.
4080  *
4081  * NOTE: Regulator system constraints must be set for this regulator before
4082  * calling this function otherwise this call will fail.
4083  */
4084 int regulator_set_current_limit(struct regulator *regulator,
4085 			       int min_uA, int max_uA)
4086 {
4087 	struct regulator_dev *rdev = regulator->rdev;
4088 	int ret;
4089 
4090 	regulator_lock(rdev);
4091 
4092 	/* sanity check */
4093 	if (!rdev->desc->ops->set_current_limit) {
4094 		ret = -EINVAL;
4095 		goto out;
4096 	}
4097 
4098 	/* constraints check */
4099 	ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
4100 	if (ret < 0)
4101 		goto out;
4102 
4103 	ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
4104 out:
4105 	regulator_unlock(rdev);
4106 	return ret;
4107 }
4108 EXPORT_SYMBOL_GPL(regulator_set_current_limit);
4109 
4110 static int _regulator_get_current_limit_unlocked(struct regulator_dev *rdev)
4111 {
4112 	/* sanity check */
4113 	if (!rdev->desc->ops->get_current_limit)
4114 		return -EINVAL;
4115 
4116 	return rdev->desc->ops->get_current_limit(rdev);
4117 }
4118 
4119 static int _regulator_get_current_limit(struct regulator_dev *rdev)
4120 {
4121 	int ret;
4122 
4123 	regulator_lock(rdev);
4124 	ret = _regulator_get_current_limit_unlocked(rdev);
4125 	regulator_unlock(rdev);
4126 
4127 	return ret;
4128 }
4129 
4130 /**
4131  * regulator_get_current_limit - get regulator output current
4132  * @regulator: regulator source
4133  *
4134  * This returns the current supplied by the specified current sink in uA.
4135  *
4136  * NOTE: If the regulator is disabled it will return the current value. This
4137  * function should not be used to determine regulator state.
4138  */
4139 int regulator_get_current_limit(struct regulator *regulator)
4140 {
4141 	return _regulator_get_current_limit(regulator->rdev);
4142 }
4143 EXPORT_SYMBOL_GPL(regulator_get_current_limit);
4144 
4145 /**
4146  * regulator_set_mode - set regulator operating mode
4147  * @regulator: regulator source
4148  * @mode: operating mode - one of the REGULATOR_MODE constants
4149  *
4150  * Set regulator operating mode to increase regulator efficiency or improve
4151  * regulation performance.
4152  *
4153  * NOTE: Regulator system constraints must be set for this regulator before
4154  * calling this function otherwise this call will fail.
4155  */
4156 int regulator_set_mode(struct regulator *regulator, unsigned int mode)
4157 {
4158 	struct regulator_dev *rdev = regulator->rdev;
4159 	int ret;
4160 	int regulator_curr_mode;
4161 
4162 	regulator_lock(rdev);
4163 
4164 	/* sanity check */
4165 	if (!rdev->desc->ops->set_mode) {
4166 		ret = -EINVAL;
4167 		goto out;
4168 	}
4169 
4170 	/* return if the same mode is requested */
4171 	if (rdev->desc->ops->get_mode) {
4172 		regulator_curr_mode = rdev->desc->ops->get_mode(rdev);
4173 		if (regulator_curr_mode == mode) {
4174 			ret = 0;
4175 			goto out;
4176 		}
4177 	}
4178 
4179 	/* constraints check */
4180 	ret = regulator_mode_constrain(rdev, &mode);
4181 	if (ret < 0)
4182 		goto out;
4183 
4184 	ret = rdev->desc->ops->set_mode(rdev, mode);
4185 out:
4186 	regulator_unlock(rdev);
4187 	return ret;
4188 }
4189 EXPORT_SYMBOL_GPL(regulator_set_mode);
4190 
4191 static unsigned int _regulator_get_mode_unlocked(struct regulator_dev *rdev)
4192 {
4193 	/* sanity check */
4194 	if (!rdev->desc->ops->get_mode)
4195 		return -EINVAL;
4196 
4197 	return rdev->desc->ops->get_mode(rdev);
4198 }
4199 
4200 static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
4201 {
4202 	int ret;
4203 
4204 	regulator_lock(rdev);
4205 	ret = _regulator_get_mode_unlocked(rdev);
4206 	regulator_unlock(rdev);
4207 
4208 	return ret;
4209 }
4210 
4211 /**
4212  * regulator_get_mode - get regulator operating mode
4213  * @regulator: regulator source
4214  *
4215  * Get the current regulator operating mode.
4216  */
4217 unsigned int regulator_get_mode(struct regulator *regulator)
4218 {
4219 	return _regulator_get_mode(regulator->rdev);
4220 }
4221 EXPORT_SYMBOL_GPL(regulator_get_mode);
4222 
4223 static int _regulator_get_error_flags(struct regulator_dev *rdev,
4224 					unsigned int *flags)
4225 {
4226 	int ret;
4227 
4228 	regulator_lock(rdev);
4229 
4230 	/* sanity check */
4231 	if (!rdev->desc->ops->get_error_flags) {
4232 		ret = -EINVAL;
4233 		goto out;
4234 	}
4235 
4236 	ret = rdev->desc->ops->get_error_flags(rdev, flags);
4237 out:
4238 	regulator_unlock(rdev);
4239 	return ret;
4240 }
4241 
4242 /**
4243  * regulator_get_error_flags - get regulator error information
4244  * @regulator: regulator source
4245  * @flags: pointer to store error flags
4246  *
4247  * Get the current regulator error information.
4248  */
4249 int regulator_get_error_flags(struct regulator *regulator,
4250 				unsigned int *flags)
4251 {
4252 	return _regulator_get_error_flags(regulator->rdev, flags);
4253 }
4254 EXPORT_SYMBOL_GPL(regulator_get_error_flags);
4255 
4256 /**
4257  * regulator_set_load - set regulator load
4258  * @regulator: regulator source
4259  * @uA_load: load current
4260  *
4261  * Notifies the regulator core of a new device load. This is then used by
4262  * DRMS (if enabled by constraints) to set the most efficient regulator
4263  * operating mode for the new regulator loading.
4264  *
4265  * Consumer devices notify their supply regulator of the maximum power
4266  * they will require (can be taken from device datasheet in the power
4267  * consumption tables) when they change operational status and hence power
4268  * state. Examples of operational state changes that can affect power
4269  * consumption are :-
4270  *
4271  *    o Device is opened / closed.
4272  *    o Device I/O is about to begin or has just finished.
4273  *    o Device is idling in between work.
4274  *
4275  * This information is also exported via sysfs to userspace.
4276  *
4277  * DRMS will sum the total requested load on the regulator and change
4278  * to the most efficient operating mode if platform constraints allow.
4279  *
4280  * NOTE: when a regulator consumer requests to have a regulator
4281  * disabled then any load that consumer requested no longer counts
4282  * toward the total requested load.  If the regulator is re-enabled
4283  * then the previously requested load will start counting again.
4284  *
4285  * If a regulator is an always-on regulator then an individual consumer's
4286  * load will still be removed if that consumer is fully disabled.
4287  *
4288  * On error a negative errno is returned.
4289  */
4290 int regulator_set_load(struct regulator *regulator, int uA_load)
4291 {
4292 	struct regulator_dev *rdev = regulator->rdev;
4293 	int old_uA_load;
4294 	int ret = 0;
4295 
4296 	regulator_lock(rdev);
4297 	old_uA_load = regulator->uA_load;
4298 	regulator->uA_load = uA_load;
4299 	if (regulator->enable_count && old_uA_load != uA_load) {
4300 		ret = drms_uA_update(rdev);
4301 		if (ret < 0)
4302 			regulator->uA_load = old_uA_load;
4303 	}
4304 	regulator_unlock(rdev);
4305 
4306 	return ret;
4307 }
4308 EXPORT_SYMBOL_GPL(regulator_set_load);
4309 
4310 /**
4311  * regulator_allow_bypass - allow the regulator to go into bypass mode
4312  *
4313  * @regulator: Regulator to configure
4314  * @enable: enable or disable bypass mode
4315  *
4316  * Allow the regulator to go into bypass mode if all other consumers
4317  * for the regulator also enable bypass mode and the machine
4318  * constraints allow this.  Bypass mode means that the regulator is
4319  * simply passing the input directly to the output with no regulation.
4320  */
4321 int regulator_allow_bypass(struct regulator *regulator, bool enable)
4322 {
4323 	struct regulator_dev *rdev = regulator->rdev;
4324 	const char *name = rdev_get_name(rdev);
4325 	int ret = 0;
4326 
4327 	if (!rdev->desc->ops->set_bypass)
4328 		return 0;
4329 
4330 	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_BYPASS))
4331 		return 0;
4332 
4333 	regulator_lock(rdev);
4334 
4335 	if (enable && !regulator->bypass) {
4336 		rdev->bypass_count++;
4337 
4338 		if (rdev->bypass_count == rdev->open_count) {
4339 			trace_regulator_bypass_enable(name);
4340 
4341 			ret = rdev->desc->ops->set_bypass(rdev, enable);
4342 			if (ret != 0)
4343 				rdev->bypass_count--;
4344 			else
4345 				trace_regulator_bypass_enable_complete(name);
4346 		}
4347 
4348 	} else if (!enable && regulator->bypass) {
4349 		rdev->bypass_count--;
4350 
4351 		if (rdev->bypass_count != rdev->open_count) {
4352 			trace_regulator_bypass_disable(name);
4353 
4354 			ret = rdev->desc->ops->set_bypass(rdev, enable);
4355 			if (ret != 0)
4356 				rdev->bypass_count++;
4357 			else
4358 				trace_regulator_bypass_disable_complete(name);
4359 		}
4360 	}
4361 
4362 	if (ret == 0)
4363 		regulator->bypass = enable;
4364 
4365 	regulator_unlock(rdev);
4366 
4367 	return ret;
4368 }
4369 EXPORT_SYMBOL_GPL(regulator_allow_bypass);
4370 
4371 /**
4372  * regulator_register_notifier - register regulator event notifier
4373  * @regulator: regulator source
4374  * @nb: notifier block
4375  *
4376  * Register notifier block to receive regulator events.
4377  */
4378 int regulator_register_notifier(struct regulator *regulator,
4379 			      struct notifier_block *nb)
4380 {
4381 	return blocking_notifier_chain_register(&regulator->rdev->notifier,
4382 						nb);
4383 }
4384 EXPORT_SYMBOL_GPL(regulator_register_notifier);
4385 
4386 /**
4387  * regulator_unregister_notifier - unregister regulator event notifier
4388  * @regulator: regulator source
4389  * @nb: notifier block
4390  *
4391  * Unregister regulator event notifier block.
4392  */
4393 int regulator_unregister_notifier(struct regulator *regulator,
4394 				struct notifier_block *nb)
4395 {
4396 	return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
4397 						  nb);
4398 }
4399 EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
4400 
4401 /* notify regulator consumers and downstream regulator consumers.
4402  * Note mutex must be held by caller.
4403  */
4404 static int _notifier_call_chain(struct regulator_dev *rdev,
4405 				  unsigned long event, void *data)
4406 {
4407 	/* call rdev chain first */
4408 	return blocking_notifier_call_chain(&rdev->notifier, event, data);
4409 }
4410 
4411 /**
4412  * regulator_bulk_get - get multiple regulator consumers
4413  *
4414  * @dev:           Device to supply
4415  * @num_consumers: Number of consumers to register
4416  * @consumers:     Configuration of consumers; clients are stored here.
4417  *
4418  * @return 0 on success, an errno on failure.
4419  *
4420  * This helper function allows drivers to get several regulator
4421  * consumers in one operation.  If any of the regulators cannot be
4422  * acquired then any regulators that were allocated will be freed
4423  * before returning to the caller.
4424  */
4425 int regulator_bulk_get(struct device *dev, int num_consumers,
4426 		       struct regulator_bulk_data *consumers)
4427 {
4428 	int i;
4429 	int ret;
4430 
4431 	for (i = 0; i < num_consumers; i++)
4432 		consumers[i].consumer = NULL;
4433 
4434 	for (i = 0; i < num_consumers; i++) {
4435 		consumers[i].consumer = regulator_get(dev,
4436 						      consumers[i].supply);
4437 		if (IS_ERR(consumers[i].consumer)) {
4438 			ret = PTR_ERR(consumers[i].consumer);
4439 			consumers[i].consumer = NULL;
4440 			goto err;
4441 		}
4442 	}
4443 
4444 	return 0;
4445 
4446 err:
4447 	if (ret != -EPROBE_DEFER)
4448 		dev_err(dev, "Failed to get supply '%s': %d\n",
4449 			consumers[i].supply, ret);
4450 	else
4451 		dev_dbg(dev, "Failed to get supply '%s', deferring\n",
4452 			consumers[i].supply);
4453 
4454 	while (--i >= 0)
4455 		regulator_put(consumers[i].consumer);
4456 
4457 	return ret;
4458 }
4459 EXPORT_SYMBOL_GPL(regulator_bulk_get);
4460 
4461 static void regulator_bulk_enable_async(void *data, async_cookie_t cookie)
4462 {
4463 	struct regulator_bulk_data *bulk = data;
4464 
4465 	bulk->ret = regulator_enable(bulk->consumer);
4466 }
4467 
4468 /**
4469  * regulator_bulk_enable - enable multiple regulator consumers
4470  *
4471  * @num_consumers: Number of consumers
4472  * @consumers:     Consumer data; clients are stored here.
4473  * @return         0 on success, an errno on failure
4474  *
4475  * This convenience API allows consumers to enable multiple regulator
4476  * clients in a single API call.  If any consumers cannot be enabled
4477  * then any others that were enabled will be disabled again prior to
4478  * return.
4479  */
4480 int regulator_bulk_enable(int num_consumers,
4481 			  struct regulator_bulk_data *consumers)
4482 {
4483 	ASYNC_DOMAIN_EXCLUSIVE(async_domain);
4484 	int i;
4485 	int ret = 0;
4486 
4487 	for (i = 0; i < num_consumers; i++) {
4488 		async_schedule_domain(regulator_bulk_enable_async,
4489 				      &consumers[i], &async_domain);
4490 	}
4491 
4492 	async_synchronize_full_domain(&async_domain);
4493 
4494 	/* If any consumer failed we need to unwind any that succeeded */
4495 	for (i = 0; i < num_consumers; i++) {
4496 		if (consumers[i].ret != 0) {
4497 			ret = consumers[i].ret;
4498 			goto err;
4499 		}
4500 	}
4501 
4502 	return 0;
4503 
4504 err:
4505 	for (i = 0; i < num_consumers; i++) {
4506 		if (consumers[i].ret < 0)
4507 			pr_err("Failed to enable %s: %d\n", consumers[i].supply,
4508 			       consumers[i].ret);
4509 		else
4510 			regulator_disable(consumers[i].consumer);
4511 	}
4512 
4513 	return ret;
4514 }
4515 EXPORT_SYMBOL_GPL(regulator_bulk_enable);
4516 
4517 /**
4518  * regulator_bulk_disable - disable multiple regulator consumers
4519  *
4520  * @num_consumers: Number of consumers
4521  * @consumers:     Consumer data; clients are stored here.
4522  * @return         0 on success, an errno on failure
4523  *
4524  * This convenience API allows consumers to disable multiple regulator
4525  * clients in a single API call.  If any consumers cannot be disabled
4526  * then any others that were disabled will be enabled again prior to
4527  * return.
4528  */
4529 int regulator_bulk_disable(int num_consumers,
4530 			   struct regulator_bulk_data *consumers)
4531 {
4532 	int i;
4533 	int ret, r;
4534 
4535 	for (i = num_consumers - 1; i >= 0; --i) {
4536 		ret = regulator_disable(consumers[i].consumer);
4537 		if (ret != 0)
4538 			goto err;
4539 	}
4540 
4541 	return 0;
4542 
4543 err:
4544 	pr_err("Failed to disable %s: %d\n", consumers[i].supply, ret);
4545 	for (++i; i < num_consumers; ++i) {
4546 		r = regulator_enable(consumers[i].consumer);
4547 		if (r != 0)
4548 			pr_err("Failed to re-enable %s: %d\n",
4549 			       consumers[i].supply, r);
4550 	}
4551 
4552 	return ret;
4553 }
4554 EXPORT_SYMBOL_GPL(regulator_bulk_disable);
4555 
4556 /**
4557  * regulator_bulk_force_disable - force disable multiple regulator consumers
4558  *
4559  * @num_consumers: Number of consumers
4560  * @consumers:     Consumer data; clients are stored here.
4561  * @return         0 on success, an errno on failure
4562  *
4563  * This convenience API allows consumers to forcibly disable multiple regulator
4564  * clients in a single API call.
4565  * NOTE: This should be used for situations when device damage will
4566  * likely occur if the regulators are not disabled (e.g. over temp).
4567  * Although regulator_force_disable function call for some consumers can
4568  * return error numbers, the function is called for all consumers.
4569  */
4570 int regulator_bulk_force_disable(int num_consumers,
4571 			   struct regulator_bulk_data *consumers)
4572 {
4573 	int i;
4574 	int ret = 0;
4575 
4576 	for (i = 0; i < num_consumers; i++) {
4577 		consumers[i].ret =
4578 			    regulator_force_disable(consumers[i].consumer);
4579 
4580 		/* Store first error for reporting */
4581 		if (consumers[i].ret && !ret)
4582 			ret = consumers[i].ret;
4583 	}
4584 
4585 	return ret;
4586 }
4587 EXPORT_SYMBOL_GPL(regulator_bulk_force_disable);
4588 
4589 /**
4590  * regulator_bulk_free - free multiple regulator consumers
4591  *
4592  * @num_consumers: Number of consumers
4593  * @consumers:     Consumer data; clients are stored here.
4594  *
4595  * This convenience API allows consumers to free multiple regulator
4596  * clients in a single API call.
4597  */
4598 void regulator_bulk_free(int num_consumers,
4599 			 struct regulator_bulk_data *consumers)
4600 {
4601 	int i;
4602 
4603 	for (i = 0; i < num_consumers; i++) {
4604 		regulator_put(consumers[i].consumer);
4605 		consumers[i].consumer = NULL;
4606 	}
4607 }
4608 EXPORT_SYMBOL_GPL(regulator_bulk_free);
4609 
4610 /**
4611  * regulator_notifier_call_chain - call regulator event notifier
4612  * @rdev: regulator source
4613  * @event: notifier block
4614  * @data: callback-specific data.
4615  *
4616  * Called by regulator drivers to notify clients a regulator event has
4617  * occurred. We also notify regulator clients downstream.
4618  * Note lock must be held by caller.
4619  */
4620 int regulator_notifier_call_chain(struct regulator_dev *rdev,
4621 				  unsigned long event, void *data)
4622 {
4623 	lockdep_assert_held_once(&rdev->mutex.base);
4624 
4625 	_notifier_call_chain(rdev, event, data);
4626 	return NOTIFY_DONE;
4627 
4628 }
4629 EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
4630 
4631 /**
4632  * regulator_mode_to_status - convert a regulator mode into a status
4633  *
4634  * @mode: Mode to convert
4635  *
4636  * Convert a regulator mode into a status.
4637  */
4638 int regulator_mode_to_status(unsigned int mode)
4639 {
4640 	switch (mode) {
4641 	case REGULATOR_MODE_FAST:
4642 		return REGULATOR_STATUS_FAST;
4643 	case REGULATOR_MODE_NORMAL:
4644 		return REGULATOR_STATUS_NORMAL;
4645 	case REGULATOR_MODE_IDLE:
4646 		return REGULATOR_STATUS_IDLE;
4647 	case REGULATOR_MODE_STANDBY:
4648 		return REGULATOR_STATUS_STANDBY;
4649 	default:
4650 		return REGULATOR_STATUS_UNDEFINED;
4651 	}
4652 }
4653 EXPORT_SYMBOL_GPL(regulator_mode_to_status);
4654 
4655 static struct attribute *regulator_dev_attrs[] = {
4656 	&dev_attr_name.attr,
4657 	&dev_attr_num_users.attr,
4658 	&dev_attr_type.attr,
4659 	&dev_attr_microvolts.attr,
4660 	&dev_attr_microamps.attr,
4661 	&dev_attr_opmode.attr,
4662 	&dev_attr_state.attr,
4663 	&dev_attr_status.attr,
4664 	&dev_attr_bypass.attr,
4665 	&dev_attr_requested_microamps.attr,
4666 	&dev_attr_min_microvolts.attr,
4667 	&dev_attr_max_microvolts.attr,
4668 	&dev_attr_min_microamps.attr,
4669 	&dev_attr_max_microamps.attr,
4670 	&dev_attr_suspend_standby_state.attr,
4671 	&dev_attr_suspend_mem_state.attr,
4672 	&dev_attr_suspend_disk_state.attr,
4673 	&dev_attr_suspend_standby_microvolts.attr,
4674 	&dev_attr_suspend_mem_microvolts.attr,
4675 	&dev_attr_suspend_disk_microvolts.attr,
4676 	&dev_attr_suspend_standby_mode.attr,
4677 	&dev_attr_suspend_mem_mode.attr,
4678 	&dev_attr_suspend_disk_mode.attr,
4679 	NULL
4680 };
4681 
4682 /*
4683  * To avoid cluttering sysfs (and memory) with useless state, only
4684  * create attributes that can be meaningfully displayed.
4685  */
4686 static umode_t regulator_attr_is_visible(struct kobject *kobj,
4687 					 struct attribute *attr, int idx)
4688 {
4689 	struct device *dev = kobj_to_dev(kobj);
4690 	struct regulator_dev *rdev = dev_to_rdev(dev);
4691 	const struct regulator_ops *ops = rdev->desc->ops;
4692 	umode_t mode = attr->mode;
4693 
4694 	/* these three are always present */
4695 	if (attr == &dev_attr_name.attr ||
4696 	    attr == &dev_attr_num_users.attr ||
4697 	    attr == &dev_attr_type.attr)
4698 		return mode;
4699 
4700 	/* some attributes need specific methods to be displayed */
4701 	if (attr == &dev_attr_microvolts.attr) {
4702 		if ((ops->get_voltage && ops->get_voltage(rdev) >= 0) ||
4703 		    (ops->get_voltage_sel && ops->get_voltage_sel(rdev) >= 0) ||
4704 		    (ops->list_voltage && ops->list_voltage(rdev, 0) >= 0) ||
4705 		    (rdev->desc->fixed_uV && rdev->desc->n_voltages == 1))
4706 			return mode;
4707 		return 0;
4708 	}
4709 
4710 	if (attr == &dev_attr_microamps.attr)
4711 		return ops->get_current_limit ? mode : 0;
4712 
4713 	if (attr == &dev_attr_opmode.attr)
4714 		return ops->get_mode ? mode : 0;
4715 
4716 	if (attr == &dev_attr_state.attr)
4717 		return (rdev->ena_pin || ops->is_enabled) ? mode : 0;
4718 
4719 	if (attr == &dev_attr_status.attr)
4720 		return ops->get_status ? mode : 0;
4721 
4722 	if (attr == &dev_attr_bypass.attr)
4723 		return ops->get_bypass ? mode : 0;
4724 
4725 	/* constraints need specific supporting methods */
4726 	if (attr == &dev_attr_min_microvolts.attr ||
4727 	    attr == &dev_attr_max_microvolts.attr)
4728 		return (ops->set_voltage || ops->set_voltage_sel) ? mode : 0;
4729 
4730 	if (attr == &dev_attr_min_microamps.attr ||
4731 	    attr == &dev_attr_max_microamps.attr)
4732 		return ops->set_current_limit ? mode : 0;
4733 
4734 	if (attr == &dev_attr_suspend_standby_state.attr ||
4735 	    attr == &dev_attr_suspend_mem_state.attr ||
4736 	    attr == &dev_attr_suspend_disk_state.attr)
4737 		return mode;
4738 
4739 	if (attr == &dev_attr_suspend_standby_microvolts.attr ||
4740 	    attr == &dev_attr_suspend_mem_microvolts.attr ||
4741 	    attr == &dev_attr_suspend_disk_microvolts.attr)
4742 		return ops->set_suspend_voltage ? mode : 0;
4743 
4744 	if (attr == &dev_attr_suspend_standby_mode.attr ||
4745 	    attr == &dev_attr_suspend_mem_mode.attr ||
4746 	    attr == &dev_attr_suspend_disk_mode.attr)
4747 		return ops->set_suspend_mode ? mode : 0;
4748 
4749 	return mode;
4750 }
4751 
4752 static const struct attribute_group regulator_dev_group = {
4753 	.attrs = regulator_dev_attrs,
4754 	.is_visible = regulator_attr_is_visible,
4755 };
4756 
4757 static const struct attribute_group *regulator_dev_groups[] = {
4758 	&regulator_dev_group,
4759 	NULL
4760 };
4761 
4762 static void regulator_dev_release(struct device *dev)
4763 {
4764 	struct regulator_dev *rdev = dev_get_drvdata(dev);
4765 
4766 	kfree(rdev->constraints);
4767 	of_node_put(rdev->dev.of_node);
4768 	kfree(rdev);
4769 }
4770 
4771 static void rdev_init_debugfs(struct regulator_dev *rdev)
4772 {
4773 	struct device *parent = rdev->dev.parent;
4774 	const char *rname = rdev_get_name(rdev);
4775 	char name[NAME_MAX];
4776 
4777 	/* Avoid duplicate debugfs directory names */
4778 	if (parent && rname == rdev->desc->name) {
4779 		snprintf(name, sizeof(name), "%s-%s", dev_name(parent),
4780 			 rname);
4781 		rname = name;
4782 	}
4783 
4784 	rdev->debugfs = debugfs_create_dir(rname, debugfs_root);
4785 	if (!rdev->debugfs) {
4786 		rdev_warn(rdev, "Failed to create debugfs directory\n");
4787 		return;
4788 	}
4789 
4790 	debugfs_create_u32("use_count", 0444, rdev->debugfs,
4791 			   &rdev->use_count);
4792 	debugfs_create_u32("open_count", 0444, rdev->debugfs,
4793 			   &rdev->open_count);
4794 	debugfs_create_u32("bypass_count", 0444, rdev->debugfs,
4795 			   &rdev->bypass_count);
4796 }
4797 
4798 static int regulator_register_resolve_supply(struct device *dev, void *data)
4799 {
4800 	struct regulator_dev *rdev = dev_to_rdev(dev);
4801 
4802 	if (regulator_resolve_supply(rdev))
4803 		rdev_dbg(rdev, "unable to resolve supply\n");
4804 
4805 	return 0;
4806 }
4807 
4808 int regulator_coupler_register(struct regulator_coupler *coupler)
4809 {
4810 	mutex_lock(&regulator_list_mutex);
4811 	list_add_tail(&coupler->list, &regulator_coupler_list);
4812 	mutex_unlock(&regulator_list_mutex);
4813 
4814 	return 0;
4815 }
4816 
4817 static struct regulator_coupler *
4818 regulator_find_coupler(struct regulator_dev *rdev)
4819 {
4820 	struct regulator_coupler *coupler;
4821 	int err;
4822 
4823 	/*
4824 	 * Note that regulators are appended to the list and the generic
4825 	 * coupler is registered first, hence it will be attached at last
4826 	 * if nobody cared.
4827 	 */
4828 	list_for_each_entry_reverse(coupler, &regulator_coupler_list, list) {
4829 		err = coupler->attach_regulator(coupler, rdev);
4830 		if (!err) {
4831 			if (!coupler->balance_voltage &&
4832 			    rdev->coupling_desc.n_coupled > 2)
4833 				goto err_unsupported;
4834 
4835 			return coupler;
4836 		}
4837 
4838 		if (err < 0)
4839 			return ERR_PTR(err);
4840 
4841 		if (err == 1)
4842 			continue;
4843 
4844 		break;
4845 	}
4846 
4847 	return ERR_PTR(-EINVAL);
4848 
4849 err_unsupported:
4850 	if (coupler->detach_regulator)
4851 		coupler->detach_regulator(coupler, rdev);
4852 
4853 	rdev_err(rdev,
4854 		"Voltage balancing for multiple regulator couples is unimplemented\n");
4855 
4856 	return ERR_PTR(-EPERM);
4857 }
4858 
4859 static void regulator_resolve_coupling(struct regulator_dev *rdev)
4860 {
4861 	struct regulator_coupler *coupler = rdev->coupling_desc.coupler;
4862 	struct coupling_desc *c_desc = &rdev->coupling_desc;
4863 	int n_coupled = c_desc->n_coupled;
4864 	struct regulator_dev *c_rdev;
4865 	int i;
4866 
4867 	for (i = 1; i < n_coupled; i++) {
4868 		/* already resolved */
4869 		if (c_desc->coupled_rdevs[i])
4870 			continue;
4871 
4872 		c_rdev = of_parse_coupled_regulator(rdev, i - 1);
4873 
4874 		if (!c_rdev)
4875 			continue;
4876 
4877 		if (c_rdev->coupling_desc.coupler != coupler) {
4878 			rdev_err(rdev, "coupler mismatch with %s\n",
4879 				 rdev_get_name(c_rdev));
4880 			return;
4881 		}
4882 
4883 		regulator_lock(c_rdev);
4884 
4885 		c_desc->coupled_rdevs[i] = c_rdev;
4886 		c_desc->n_resolved++;
4887 
4888 		regulator_unlock(c_rdev);
4889 
4890 		regulator_resolve_coupling(c_rdev);
4891 	}
4892 }
4893 
4894 static void regulator_remove_coupling(struct regulator_dev *rdev)
4895 {
4896 	struct regulator_coupler *coupler = rdev->coupling_desc.coupler;
4897 	struct coupling_desc *__c_desc, *c_desc = &rdev->coupling_desc;
4898 	struct regulator_dev *__c_rdev, *c_rdev;
4899 	unsigned int __n_coupled, n_coupled;
4900 	int i, k;
4901 	int err;
4902 
4903 	n_coupled = c_desc->n_coupled;
4904 
4905 	for (i = 1; i < n_coupled; i++) {
4906 		c_rdev = c_desc->coupled_rdevs[i];
4907 
4908 		if (!c_rdev)
4909 			continue;
4910 
4911 		regulator_lock(c_rdev);
4912 
4913 		__c_desc = &c_rdev->coupling_desc;
4914 		__n_coupled = __c_desc->n_coupled;
4915 
4916 		for (k = 1; k < __n_coupled; k++) {
4917 			__c_rdev = __c_desc->coupled_rdevs[k];
4918 
4919 			if (__c_rdev == rdev) {
4920 				__c_desc->coupled_rdevs[k] = NULL;
4921 				__c_desc->n_resolved--;
4922 				break;
4923 			}
4924 		}
4925 
4926 		regulator_unlock(c_rdev);
4927 
4928 		c_desc->coupled_rdevs[i] = NULL;
4929 		c_desc->n_resolved--;
4930 	}
4931 
4932 	if (coupler && coupler->detach_regulator) {
4933 		err = coupler->detach_regulator(coupler, rdev);
4934 		if (err)
4935 			rdev_err(rdev, "failed to detach from coupler: %d\n",
4936 				 err);
4937 	}
4938 
4939 	kfree(rdev->coupling_desc.coupled_rdevs);
4940 	rdev->coupling_desc.coupled_rdevs = NULL;
4941 }
4942 
4943 static int regulator_init_coupling(struct regulator_dev *rdev)
4944 {
4945 	int err, n_phandles;
4946 	size_t alloc_size;
4947 
4948 	if (!IS_ENABLED(CONFIG_OF))
4949 		n_phandles = 0;
4950 	else
4951 		n_phandles = of_get_n_coupled(rdev);
4952 
4953 	alloc_size = sizeof(*rdev) * (n_phandles + 1);
4954 
4955 	rdev->coupling_desc.coupled_rdevs = kzalloc(alloc_size, GFP_KERNEL);
4956 	if (!rdev->coupling_desc.coupled_rdevs)
4957 		return -ENOMEM;
4958 
4959 	/*
4960 	 * Every regulator should always have coupling descriptor filled with
4961 	 * at least pointer to itself.
4962 	 */
4963 	rdev->coupling_desc.coupled_rdevs[0] = rdev;
4964 	rdev->coupling_desc.n_coupled = n_phandles + 1;
4965 	rdev->coupling_desc.n_resolved++;
4966 
4967 	/* regulator isn't coupled */
4968 	if (n_phandles == 0)
4969 		return 0;
4970 
4971 	if (!of_check_coupling_data(rdev))
4972 		return -EPERM;
4973 
4974 	rdev->coupling_desc.coupler = regulator_find_coupler(rdev);
4975 	if (IS_ERR(rdev->coupling_desc.coupler)) {
4976 		err = PTR_ERR(rdev->coupling_desc.coupler);
4977 		rdev_err(rdev, "failed to get coupler: %d\n", err);
4978 		return err;
4979 	}
4980 
4981 	return 0;
4982 }
4983 
4984 static int generic_coupler_attach(struct regulator_coupler *coupler,
4985 				  struct regulator_dev *rdev)
4986 {
4987 	if (rdev->coupling_desc.n_coupled > 2) {
4988 		rdev_err(rdev,
4989 			 "Voltage balancing for multiple regulator couples is unimplemented\n");
4990 		return -EPERM;
4991 	}
4992 
4993 	if (!rdev->constraints->always_on) {
4994 		rdev_err(rdev,
4995 			 "Coupling of a non always-on regulator is unimplemented\n");
4996 		return -ENOTSUPP;
4997 	}
4998 
4999 	return 0;
5000 }
5001 
5002 static struct regulator_coupler generic_regulator_coupler = {
5003 	.attach_regulator = generic_coupler_attach,
5004 };
5005 
5006 /**
5007  * regulator_register - register regulator
5008  * @regulator_desc: regulator to register
5009  * @cfg: runtime configuration for regulator
5010  *
5011  * Called by regulator drivers to register a regulator.
5012  * Returns a valid pointer to struct regulator_dev on success
5013  * or an ERR_PTR() on error.
5014  */
5015 struct regulator_dev *
5016 regulator_register(const struct regulator_desc *regulator_desc,
5017 		   const struct regulator_config *cfg)
5018 {
5019 	const struct regulation_constraints *constraints = NULL;
5020 	const struct regulator_init_data *init_data;
5021 	struct regulator_config *config = NULL;
5022 	static atomic_t regulator_no = ATOMIC_INIT(-1);
5023 	struct regulator_dev *rdev;
5024 	bool dangling_cfg_gpiod = false;
5025 	bool dangling_of_gpiod = false;
5026 	bool reg_device_fail = false;
5027 	struct device *dev;
5028 	int ret, i;
5029 
5030 	if (cfg == NULL)
5031 		return ERR_PTR(-EINVAL);
5032 	if (cfg->ena_gpiod)
5033 		dangling_cfg_gpiod = true;
5034 	if (regulator_desc == NULL) {
5035 		ret = -EINVAL;
5036 		goto rinse;
5037 	}
5038 
5039 	dev = cfg->dev;
5040 	WARN_ON(!dev);
5041 
5042 	if (regulator_desc->name == NULL || regulator_desc->ops == NULL) {
5043 		ret = -EINVAL;
5044 		goto rinse;
5045 	}
5046 
5047 	if (regulator_desc->type != REGULATOR_VOLTAGE &&
5048 	    regulator_desc->type != REGULATOR_CURRENT) {
5049 		ret = -EINVAL;
5050 		goto rinse;
5051 	}
5052 
5053 	/* Only one of each should be implemented */
5054 	WARN_ON(regulator_desc->ops->get_voltage &&
5055 		regulator_desc->ops->get_voltage_sel);
5056 	WARN_ON(regulator_desc->ops->set_voltage &&
5057 		regulator_desc->ops->set_voltage_sel);
5058 
5059 	/* If we're using selectors we must implement list_voltage. */
5060 	if (regulator_desc->ops->get_voltage_sel &&
5061 	    !regulator_desc->ops->list_voltage) {
5062 		ret = -EINVAL;
5063 		goto rinse;
5064 	}
5065 	if (regulator_desc->ops->set_voltage_sel &&
5066 	    !regulator_desc->ops->list_voltage) {
5067 		ret = -EINVAL;
5068 		goto rinse;
5069 	}
5070 
5071 	rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
5072 	if (rdev == NULL) {
5073 		ret = -ENOMEM;
5074 		goto rinse;
5075 	}
5076 
5077 	/*
5078 	 * Duplicate the config so the driver could override it after
5079 	 * parsing init data.
5080 	 */
5081 	config = kmemdup(cfg, sizeof(*cfg), GFP_KERNEL);
5082 	if (config == NULL) {
5083 		kfree(rdev);
5084 		ret = -ENOMEM;
5085 		goto rinse;
5086 	}
5087 
5088 	init_data = regulator_of_get_init_data(dev, regulator_desc, config,
5089 					       &rdev->dev.of_node);
5090 
5091 	/*
5092 	 * Sometimes not all resources are probed already so we need to take
5093 	 * that into account. This happens most the time if the ena_gpiod comes
5094 	 * from a gpio extender or something else.
5095 	 */
5096 	if (PTR_ERR(init_data) == -EPROBE_DEFER) {
5097 		kfree(config);
5098 		kfree(rdev);
5099 		ret = -EPROBE_DEFER;
5100 		goto rinse;
5101 	}
5102 
5103 	/*
5104 	 * We need to keep track of any GPIO descriptor coming from the
5105 	 * device tree until we have handled it over to the core. If the
5106 	 * config that was passed in to this function DOES NOT contain
5107 	 * a descriptor, and the config after this call DOES contain
5108 	 * a descriptor, we definitely got one from parsing the device
5109 	 * tree.
5110 	 */
5111 	if (!cfg->ena_gpiod && config->ena_gpiod)
5112 		dangling_of_gpiod = true;
5113 	if (!init_data) {
5114 		init_data = config->init_data;
5115 		rdev->dev.of_node = of_node_get(config->of_node);
5116 	}
5117 
5118 	ww_mutex_init(&rdev->mutex, &regulator_ww_class);
5119 	rdev->reg_data = config->driver_data;
5120 	rdev->owner = regulator_desc->owner;
5121 	rdev->desc = regulator_desc;
5122 	if (config->regmap)
5123 		rdev->regmap = config->regmap;
5124 	else if (dev_get_regmap(dev, NULL))
5125 		rdev->regmap = dev_get_regmap(dev, NULL);
5126 	else if (dev->parent)
5127 		rdev->regmap = dev_get_regmap(dev->parent, NULL);
5128 	INIT_LIST_HEAD(&rdev->consumer_list);
5129 	INIT_LIST_HEAD(&rdev->list);
5130 	BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
5131 	INIT_DELAYED_WORK(&rdev->disable_work, regulator_disable_work);
5132 
5133 	/* preform any regulator specific init */
5134 	if (init_data && init_data->regulator_init) {
5135 		ret = init_data->regulator_init(rdev->reg_data);
5136 		if (ret < 0)
5137 			goto clean;
5138 	}
5139 
5140 	if (config->ena_gpiod) {
5141 		mutex_lock(&regulator_list_mutex);
5142 		ret = regulator_ena_gpio_request(rdev, config);
5143 		mutex_unlock(&regulator_list_mutex);
5144 		if (ret != 0) {
5145 			rdev_err(rdev, "Failed to request enable GPIO: %d\n",
5146 				 ret);
5147 			goto clean;
5148 		}
5149 		/* The regulator core took over the GPIO descriptor */
5150 		dangling_cfg_gpiod = false;
5151 		dangling_of_gpiod = false;
5152 	}
5153 
5154 	/* register with sysfs */
5155 	rdev->dev.class = &regulator_class;
5156 	rdev->dev.parent = dev;
5157 	dev_set_name(&rdev->dev, "regulator.%lu",
5158 		    (unsigned long) atomic_inc_return(&regulator_no));
5159 
5160 	/* set regulator constraints */
5161 	if (init_data)
5162 		constraints = &init_data->constraints;
5163 
5164 	if (init_data && init_data->supply_regulator)
5165 		rdev->supply_name = init_data->supply_regulator;
5166 	else if (regulator_desc->supply_name)
5167 		rdev->supply_name = regulator_desc->supply_name;
5168 
5169 	/*
5170 	 * Attempt to resolve the regulator supply, if specified,
5171 	 * but don't return an error if we fail because we will try
5172 	 * to resolve it again later as more regulators are added.
5173 	 */
5174 	if (regulator_resolve_supply(rdev))
5175 		rdev_dbg(rdev, "unable to resolve supply\n");
5176 
5177 	ret = set_machine_constraints(rdev, constraints);
5178 	if (ret < 0)
5179 		goto wash;
5180 
5181 	mutex_lock(&regulator_list_mutex);
5182 	ret = regulator_init_coupling(rdev);
5183 	mutex_unlock(&regulator_list_mutex);
5184 	if (ret < 0)
5185 		goto wash;
5186 
5187 	/* add consumers devices */
5188 	if (init_data) {
5189 		mutex_lock(&regulator_list_mutex);
5190 		for (i = 0; i < init_data->num_consumer_supplies; i++) {
5191 			ret = set_consumer_device_supply(rdev,
5192 				init_data->consumer_supplies[i].dev_name,
5193 				init_data->consumer_supplies[i].supply);
5194 			if (ret < 0) {
5195 				mutex_unlock(&regulator_list_mutex);
5196 				dev_err(dev, "Failed to set supply %s\n",
5197 					init_data->consumer_supplies[i].supply);
5198 				goto unset_supplies;
5199 			}
5200 		}
5201 		mutex_unlock(&regulator_list_mutex);
5202 	}
5203 
5204 	if (!rdev->desc->ops->get_voltage &&
5205 	    !rdev->desc->ops->list_voltage &&
5206 	    !rdev->desc->fixed_uV)
5207 		rdev->is_switch = true;
5208 
5209 	dev_set_drvdata(&rdev->dev, rdev);
5210 	ret = device_register(&rdev->dev);
5211 	if (ret != 0) {
5212 		reg_device_fail = true;
5213 		goto unset_supplies;
5214 	}
5215 
5216 	rdev_init_debugfs(rdev);
5217 
5218 	/* try to resolve regulators coupling since a new one was registered */
5219 	mutex_lock(&regulator_list_mutex);
5220 	regulator_resolve_coupling(rdev);
5221 	mutex_unlock(&regulator_list_mutex);
5222 
5223 	/* try to resolve regulators supply since a new one was registered */
5224 	class_for_each_device(&regulator_class, NULL, NULL,
5225 			      regulator_register_resolve_supply);
5226 	kfree(config);
5227 	return rdev;
5228 
5229 unset_supplies:
5230 	mutex_lock(&regulator_list_mutex);
5231 	unset_regulator_supplies(rdev);
5232 	regulator_remove_coupling(rdev);
5233 	mutex_unlock(&regulator_list_mutex);
5234 wash:
5235 	kfree(rdev->coupling_desc.coupled_rdevs);
5236 	kfree(rdev->constraints);
5237 	mutex_lock(&regulator_list_mutex);
5238 	regulator_ena_gpio_free(rdev);
5239 	mutex_unlock(&regulator_list_mutex);
5240 clean:
5241 	if (dangling_of_gpiod)
5242 		gpiod_put(config->ena_gpiod);
5243 	if (reg_device_fail)
5244 		put_device(&rdev->dev);
5245 	else
5246 		kfree(rdev);
5247 	kfree(config);
5248 rinse:
5249 	if (dangling_cfg_gpiod)
5250 		gpiod_put(cfg->ena_gpiod);
5251 	return ERR_PTR(ret);
5252 }
5253 EXPORT_SYMBOL_GPL(regulator_register);
5254 
5255 /**
5256  * regulator_unregister - unregister regulator
5257  * @rdev: regulator to unregister
5258  *
5259  * Called by regulator drivers to unregister a regulator.
5260  */
5261 void regulator_unregister(struct regulator_dev *rdev)
5262 {
5263 	if (rdev == NULL)
5264 		return;
5265 
5266 	if (rdev->supply) {
5267 		while (rdev->use_count--)
5268 			regulator_disable(rdev->supply);
5269 		regulator_put(rdev->supply);
5270 	}
5271 
5272 	flush_work(&rdev->disable_work.work);
5273 
5274 	mutex_lock(&regulator_list_mutex);
5275 
5276 	debugfs_remove_recursive(rdev->debugfs);
5277 	WARN_ON(rdev->open_count);
5278 	regulator_remove_coupling(rdev);
5279 	unset_regulator_supplies(rdev);
5280 	list_del(&rdev->list);
5281 	regulator_ena_gpio_free(rdev);
5282 	device_unregister(&rdev->dev);
5283 
5284 	mutex_unlock(&regulator_list_mutex);
5285 }
5286 EXPORT_SYMBOL_GPL(regulator_unregister);
5287 
5288 #ifdef CONFIG_SUSPEND
5289 /**
5290  * regulator_suspend - prepare regulators for system wide suspend
5291  * @dev: ``&struct device`` pointer that is passed to _regulator_suspend()
5292  *
5293  * Configure each regulator with it's suspend operating parameters for state.
5294  */
5295 static int regulator_suspend(struct device *dev)
5296 {
5297 	struct regulator_dev *rdev = dev_to_rdev(dev);
5298 	suspend_state_t state = pm_suspend_target_state;
5299 	int ret;
5300 
5301 	regulator_lock(rdev);
5302 	ret = suspend_set_state(rdev, state);
5303 	regulator_unlock(rdev);
5304 
5305 	return ret;
5306 }
5307 
5308 static int regulator_resume(struct device *dev)
5309 {
5310 	suspend_state_t state = pm_suspend_target_state;
5311 	struct regulator_dev *rdev = dev_to_rdev(dev);
5312 	struct regulator_state *rstate;
5313 	int ret = 0;
5314 
5315 	rstate = regulator_get_suspend_state(rdev, state);
5316 	if (rstate == NULL)
5317 		return 0;
5318 
5319 	regulator_lock(rdev);
5320 
5321 	if (rdev->desc->ops->resume &&
5322 	    (rstate->enabled == ENABLE_IN_SUSPEND ||
5323 	     rstate->enabled == DISABLE_IN_SUSPEND))
5324 		ret = rdev->desc->ops->resume(rdev);
5325 
5326 	regulator_unlock(rdev);
5327 
5328 	return ret;
5329 }
5330 #else /* !CONFIG_SUSPEND */
5331 
5332 #define regulator_suspend	NULL
5333 #define regulator_resume	NULL
5334 
5335 #endif /* !CONFIG_SUSPEND */
5336 
5337 #ifdef CONFIG_PM
5338 static const struct dev_pm_ops __maybe_unused regulator_pm_ops = {
5339 	.suspend	= regulator_suspend,
5340 	.resume		= regulator_resume,
5341 };
5342 #endif
5343 
5344 struct class regulator_class = {
5345 	.name = "regulator",
5346 	.dev_release = regulator_dev_release,
5347 	.dev_groups = regulator_dev_groups,
5348 #ifdef CONFIG_PM
5349 	.pm = &regulator_pm_ops,
5350 #endif
5351 };
5352 /**
5353  * regulator_has_full_constraints - the system has fully specified constraints
5354  *
5355  * Calling this function will cause the regulator API to disable all
5356  * regulators which have a zero use count and don't have an always_on
5357  * constraint in a late_initcall.
5358  *
5359  * The intention is that this will become the default behaviour in a
5360  * future kernel release so users are encouraged to use this facility
5361  * now.
5362  */
5363 void regulator_has_full_constraints(void)
5364 {
5365 	has_full_constraints = 1;
5366 }
5367 EXPORT_SYMBOL_GPL(regulator_has_full_constraints);
5368 
5369 /**
5370  * rdev_get_drvdata - get rdev regulator driver data
5371  * @rdev: regulator
5372  *
5373  * Get rdev regulator driver private data. This call can be used in the
5374  * regulator driver context.
5375  */
5376 void *rdev_get_drvdata(struct regulator_dev *rdev)
5377 {
5378 	return rdev->reg_data;
5379 }
5380 EXPORT_SYMBOL_GPL(rdev_get_drvdata);
5381 
5382 /**
5383  * regulator_get_drvdata - get regulator driver data
5384  * @regulator: regulator
5385  *
5386  * Get regulator driver private data. This call can be used in the consumer
5387  * driver context when non API regulator specific functions need to be called.
5388  */
5389 void *regulator_get_drvdata(struct regulator *regulator)
5390 {
5391 	return regulator->rdev->reg_data;
5392 }
5393 EXPORT_SYMBOL_GPL(regulator_get_drvdata);
5394 
5395 /**
5396  * regulator_set_drvdata - set regulator driver data
5397  * @regulator: regulator
5398  * @data: data
5399  */
5400 void regulator_set_drvdata(struct regulator *regulator, void *data)
5401 {
5402 	regulator->rdev->reg_data = data;
5403 }
5404 EXPORT_SYMBOL_GPL(regulator_set_drvdata);
5405 
5406 /**
5407  * regulator_get_id - get regulator ID
5408  * @rdev: regulator
5409  */
5410 int rdev_get_id(struct regulator_dev *rdev)
5411 {
5412 	return rdev->desc->id;
5413 }
5414 EXPORT_SYMBOL_GPL(rdev_get_id);
5415 
5416 struct device *rdev_get_dev(struct regulator_dev *rdev)
5417 {
5418 	return &rdev->dev;
5419 }
5420 EXPORT_SYMBOL_GPL(rdev_get_dev);
5421 
5422 struct regmap *rdev_get_regmap(struct regulator_dev *rdev)
5423 {
5424 	return rdev->regmap;
5425 }
5426 EXPORT_SYMBOL_GPL(rdev_get_regmap);
5427 
5428 void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
5429 {
5430 	return reg_init_data->driver_data;
5431 }
5432 EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
5433 
5434 #ifdef CONFIG_DEBUG_FS
5435 static int supply_map_show(struct seq_file *sf, void *data)
5436 {
5437 	struct regulator_map *map;
5438 
5439 	list_for_each_entry(map, &regulator_map_list, list) {
5440 		seq_printf(sf, "%s -> %s.%s\n",
5441 				rdev_get_name(map->regulator), map->dev_name,
5442 				map->supply);
5443 	}
5444 
5445 	return 0;
5446 }
5447 DEFINE_SHOW_ATTRIBUTE(supply_map);
5448 
5449 struct summary_data {
5450 	struct seq_file *s;
5451 	struct regulator_dev *parent;
5452 	int level;
5453 };
5454 
5455 static void regulator_summary_show_subtree(struct seq_file *s,
5456 					   struct regulator_dev *rdev,
5457 					   int level);
5458 
5459 static int regulator_summary_show_children(struct device *dev, void *data)
5460 {
5461 	struct regulator_dev *rdev = dev_to_rdev(dev);
5462 	struct summary_data *summary_data = data;
5463 
5464 	if (rdev->supply && rdev->supply->rdev == summary_data->parent)
5465 		regulator_summary_show_subtree(summary_data->s, rdev,
5466 					       summary_data->level + 1);
5467 
5468 	return 0;
5469 }
5470 
5471 static void regulator_summary_show_subtree(struct seq_file *s,
5472 					   struct regulator_dev *rdev,
5473 					   int level)
5474 {
5475 	struct regulation_constraints *c;
5476 	struct regulator *consumer;
5477 	struct summary_data summary_data;
5478 	unsigned int opmode;
5479 
5480 	if (!rdev)
5481 		return;
5482 
5483 	opmode = _regulator_get_mode_unlocked(rdev);
5484 	seq_printf(s, "%*s%-*s %3d %4d %6d %7s ",
5485 		   level * 3 + 1, "",
5486 		   30 - level * 3, rdev_get_name(rdev),
5487 		   rdev->use_count, rdev->open_count, rdev->bypass_count,
5488 		   regulator_opmode_to_str(opmode));
5489 
5490 	seq_printf(s, "%5dmV ", regulator_get_voltage_rdev(rdev) / 1000);
5491 	seq_printf(s, "%5dmA ",
5492 		   _regulator_get_current_limit_unlocked(rdev) / 1000);
5493 
5494 	c = rdev->constraints;
5495 	if (c) {
5496 		switch (rdev->desc->type) {
5497 		case REGULATOR_VOLTAGE:
5498 			seq_printf(s, "%5dmV %5dmV ",
5499 				   c->min_uV / 1000, c->max_uV / 1000);
5500 			break;
5501 		case REGULATOR_CURRENT:
5502 			seq_printf(s, "%5dmA %5dmA ",
5503 				   c->min_uA / 1000, c->max_uA / 1000);
5504 			break;
5505 		}
5506 	}
5507 
5508 	seq_puts(s, "\n");
5509 
5510 	list_for_each_entry(consumer, &rdev->consumer_list, list) {
5511 		if (consumer->dev && consumer->dev->class == &regulator_class)
5512 			continue;
5513 
5514 		seq_printf(s, "%*s%-*s ",
5515 			   (level + 1) * 3 + 1, "",
5516 			   30 - (level + 1) * 3,
5517 			   consumer->supply_name ? consumer->supply_name :
5518 			   consumer->dev ? dev_name(consumer->dev) : "deviceless");
5519 
5520 		switch (rdev->desc->type) {
5521 		case REGULATOR_VOLTAGE:
5522 			seq_printf(s, "%3d %33dmA%c%5dmV %5dmV",
5523 				   consumer->enable_count,
5524 				   consumer->uA_load / 1000,
5525 				   consumer->uA_load && !consumer->enable_count ?
5526 				   '*' : ' ',
5527 				   consumer->voltage[PM_SUSPEND_ON].min_uV / 1000,
5528 				   consumer->voltage[PM_SUSPEND_ON].max_uV / 1000);
5529 			break;
5530 		case REGULATOR_CURRENT:
5531 			break;
5532 		}
5533 
5534 		seq_puts(s, "\n");
5535 	}
5536 
5537 	summary_data.s = s;
5538 	summary_data.level = level;
5539 	summary_data.parent = rdev;
5540 
5541 	class_for_each_device(&regulator_class, NULL, &summary_data,
5542 			      regulator_summary_show_children);
5543 }
5544 
5545 struct summary_lock_data {
5546 	struct ww_acquire_ctx *ww_ctx;
5547 	struct regulator_dev **new_contended_rdev;
5548 	struct regulator_dev **old_contended_rdev;
5549 };
5550 
5551 static int regulator_summary_lock_one(struct device *dev, void *data)
5552 {
5553 	struct regulator_dev *rdev = dev_to_rdev(dev);
5554 	struct summary_lock_data *lock_data = data;
5555 	int ret = 0;
5556 
5557 	if (rdev != *lock_data->old_contended_rdev) {
5558 		ret = regulator_lock_nested(rdev, lock_data->ww_ctx);
5559 
5560 		if (ret == -EDEADLK)
5561 			*lock_data->new_contended_rdev = rdev;
5562 		else
5563 			WARN_ON_ONCE(ret);
5564 	} else {
5565 		*lock_data->old_contended_rdev = NULL;
5566 	}
5567 
5568 	return ret;
5569 }
5570 
5571 static int regulator_summary_unlock_one(struct device *dev, void *data)
5572 {
5573 	struct regulator_dev *rdev = dev_to_rdev(dev);
5574 	struct summary_lock_data *lock_data = data;
5575 
5576 	if (lock_data) {
5577 		if (rdev == *lock_data->new_contended_rdev)
5578 			return -EDEADLK;
5579 	}
5580 
5581 	regulator_unlock(rdev);
5582 
5583 	return 0;
5584 }
5585 
5586 static int regulator_summary_lock_all(struct ww_acquire_ctx *ww_ctx,
5587 				      struct regulator_dev **new_contended_rdev,
5588 				      struct regulator_dev **old_contended_rdev)
5589 {
5590 	struct summary_lock_data lock_data;
5591 	int ret;
5592 
5593 	lock_data.ww_ctx = ww_ctx;
5594 	lock_data.new_contended_rdev = new_contended_rdev;
5595 	lock_data.old_contended_rdev = old_contended_rdev;
5596 
5597 	ret = class_for_each_device(&regulator_class, NULL, &lock_data,
5598 				    regulator_summary_lock_one);
5599 	if (ret)
5600 		class_for_each_device(&regulator_class, NULL, &lock_data,
5601 				      regulator_summary_unlock_one);
5602 
5603 	return ret;
5604 }
5605 
5606 static void regulator_summary_lock(struct ww_acquire_ctx *ww_ctx)
5607 {
5608 	struct regulator_dev *new_contended_rdev = NULL;
5609 	struct regulator_dev *old_contended_rdev = NULL;
5610 	int err;
5611 
5612 	mutex_lock(&regulator_list_mutex);
5613 
5614 	ww_acquire_init(ww_ctx, &regulator_ww_class);
5615 
5616 	do {
5617 		if (new_contended_rdev) {
5618 			ww_mutex_lock_slow(&new_contended_rdev->mutex, ww_ctx);
5619 			old_contended_rdev = new_contended_rdev;
5620 			old_contended_rdev->ref_cnt++;
5621 		}
5622 
5623 		err = regulator_summary_lock_all(ww_ctx,
5624 						 &new_contended_rdev,
5625 						 &old_contended_rdev);
5626 
5627 		if (old_contended_rdev)
5628 			regulator_unlock(old_contended_rdev);
5629 
5630 	} while (err == -EDEADLK);
5631 
5632 	ww_acquire_done(ww_ctx);
5633 }
5634 
5635 static void regulator_summary_unlock(struct ww_acquire_ctx *ww_ctx)
5636 {
5637 	class_for_each_device(&regulator_class, NULL, NULL,
5638 			      regulator_summary_unlock_one);
5639 	ww_acquire_fini(ww_ctx);
5640 
5641 	mutex_unlock(&regulator_list_mutex);
5642 }
5643 
5644 static int regulator_summary_show_roots(struct device *dev, void *data)
5645 {
5646 	struct regulator_dev *rdev = dev_to_rdev(dev);
5647 	struct seq_file *s = data;
5648 
5649 	if (!rdev->supply)
5650 		regulator_summary_show_subtree(s, rdev, 0);
5651 
5652 	return 0;
5653 }
5654 
5655 static int regulator_summary_show(struct seq_file *s, void *data)
5656 {
5657 	struct ww_acquire_ctx ww_ctx;
5658 
5659 	seq_puts(s, " regulator                      use open bypass  opmode voltage current     min     max\n");
5660 	seq_puts(s, "---------------------------------------------------------------------------------------\n");
5661 
5662 	regulator_summary_lock(&ww_ctx);
5663 
5664 	class_for_each_device(&regulator_class, NULL, s,
5665 			      regulator_summary_show_roots);
5666 
5667 	regulator_summary_unlock(&ww_ctx);
5668 
5669 	return 0;
5670 }
5671 DEFINE_SHOW_ATTRIBUTE(regulator_summary);
5672 #endif /* CONFIG_DEBUG_FS */
5673 
5674 static int __init regulator_init(void)
5675 {
5676 	int ret;
5677 
5678 	ret = class_register(&regulator_class);
5679 
5680 	debugfs_root = debugfs_create_dir("regulator", NULL);
5681 	if (!debugfs_root)
5682 		pr_warn("regulator: Failed to create debugfs directory\n");
5683 
5684 #ifdef CONFIG_DEBUG_FS
5685 	debugfs_create_file("supply_map", 0444, debugfs_root, NULL,
5686 			    &supply_map_fops);
5687 
5688 	debugfs_create_file("regulator_summary", 0444, debugfs_root,
5689 			    NULL, &regulator_summary_fops);
5690 #endif
5691 	regulator_dummy_init();
5692 
5693 	regulator_coupler_register(&generic_regulator_coupler);
5694 
5695 	return ret;
5696 }
5697 
5698 /* init early to allow our consumers to complete system booting */
5699 core_initcall(regulator_init);
5700 
5701 static int regulator_late_cleanup(struct device *dev, void *data)
5702 {
5703 	struct regulator_dev *rdev = dev_to_rdev(dev);
5704 	const struct regulator_ops *ops = rdev->desc->ops;
5705 	struct regulation_constraints *c = rdev->constraints;
5706 	int enabled, ret;
5707 
5708 	if (c && c->always_on)
5709 		return 0;
5710 
5711 	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_STATUS))
5712 		return 0;
5713 
5714 	regulator_lock(rdev);
5715 
5716 	if (rdev->use_count)
5717 		goto unlock;
5718 
5719 	/* If we can't read the status assume it's on. */
5720 	if (ops->is_enabled)
5721 		enabled = ops->is_enabled(rdev);
5722 	else
5723 		enabled = 1;
5724 
5725 	if (!enabled)
5726 		goto unlock;
5727 
5728 	if (have_full_constraints()) {
5729 		/* We log since this may kill the system if it goes
5730 		 * wrong. */
5731 		rdev_info(rdev, "disabling\n");
5732 		ret = _regulator_do_disable(rdev);
5733 		if (ret != 0)
5734 			rdev_err(rdev, "couldn't disable: %d\n", ret);
5735 	} else {
5736 		/* The intention is that in future we will
5737 		 * assume that full constraints are provided
5738 		 * so warn even if we aren't going to do
5739 		 * anything here.
5740 		 */
5741 		rdev_warn(rdev, "incomplete constraints, leaving on\n");
5742 	}
5743 
5744 unlock:
5745 	regulator_unlock(rdev);
5746 
5747 	return 0;
5748 }
5749 
5750 static void regulator_init_complete_work_function(struct work_struct *work)
5751 {
5752 	/*
5753 	 * Regulators may had failed to resolve their input supplies
5754 	 * when were registered, either because the input supply was
5755 	 * not registered yet or because its parent device was not
5756 	 * bound yet. So attempt to resolve the input supplies for
5757 	 * pending regulators before trying to disable unused ones.
5758 	 */
5759 	class_for_each_device(&regulator_class, NULL, NULL,
5760 			      regulator_register_resolve_supply);
5761 
5762 	/* If we have a full configuration then disable any regulators
5763 	 * we have permission to change the status for and which are
5764 	 * not in use or always_on.  This is effectively the default
5765 	 * for DT and ACPI as they have full constraints.
5766 	 */
5767 	class_for_each_device(&regulator_class, NULL, NULL,
5768 			      regulator_late_cleanup);
5769 }
5770 
5771 static DECLARE_DELAYED_WORK(regulator_init_complete_work,
5772 			    regulator_init_complete_work_function);
5773 
5774 static int __init regulator_init_complete(void)
5775 {
5776 	/*
5777 	 * Since DT doesn't provide an idiomatic mechanism for
5778 	 * enabling full constraints and since it's much more natural
5779 	 * with DT to provide them just assume that a DT enabled
5780 	 * system has full constraints.
5781 	 */
5782 	if (of_have_populated_dt())
5783 		has_full_constraints = true;
5784 
5785 	/*
5786 	 * We punt completion for an arbitrary amount of time since
5787 	 * systems like distros will load many drivers from userspace
5788 	 * so consumers might not always be ready yet, this is
5789 	 * particularly an issue with laptops where this might bounce
5790 	 * the display off then on.  Ideally we'd get a notification
5791 	 * from userspace when this happens but we don't so just wait
5792 	 * a bit and hope we waited long enough.  It'd be better if
5793 	 * we'd only do this on systems that need it, and a kernel
5794 	 * command line option might be useful.
5795 	 */
5796 	schedule_delayed_work(&regulator_init_complete_work,
5797 			      msecs_to_jiffies(30000));
5798 
5799 	return 0;
5800 }
5801 late_initcall_sync(regulator_init_complete);
5802