xref: /openbmc/linux/drivers/regulator/core.c (revision 2f164822)
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 static DEFINE_WW_CLASS(regulator_ww_class);
37 static DEFINE_MUTEX(regulator_nesting_mutex);
38 static DEFINE_MUTEX(regulator_list_mutex);
39 static LIST_HEAD(regulator_map_list);
40 static LIST_HEAD(regulator_ena_gpio_list);
41 static LIST_HEAD(regulator_supply_alias_list);
42 static LIST_HEAD(regulator_coupler_list);
43 static bool has_full_constraints;
44 
45 static struct dentry *debugfs_root;
46 
47 /*
48  * struct regulator_map
49  *
50  * Used to provide symbolic supply names to devices.
51  */
52 struct regulator_map {
53 	struct list_head list;
54 	const char *dev_name;   /* The dev_name() for the consumer */
55 	const char *supply;
56 	struct regulator_dev *regulator;
57 };
58 
59 /*
60  * struct regulator_enable_gpio
61  *
62  * Management for shared enable GPIO pin
63  */
64 struct regulator_enable_gpio {
65 	struct list_head list;
66 	struct gpio_desc *gpiod;
67 	u32 enable_count;	/* a number of enabled shared GPIO */
68 	u32 request_count;	/* a number of requested shared GPIO */
69 };
70 
71 /*
72  * struct regulator_supply_alias
73  *
74  * Used to map lookups for a supply onto an alternative device.
75  */
76 struct regulator_supply_alias {
77 	struct list_head list;
78 	struct device *src_dev;
79 	const char *src_supply;
80 	struct device *alias_dev;
81 	const char *alias_supply;
82 };
83 
84 static int _regulator_is_enabled(struct regulator_dev *rdev);
85 static int _regulator_disable(struct regulator *regulator);
86 static int _regulator_get_error_flags(struct regulator_dev *rdev, unsigned int *flags);
87 static int _regulator_get_current_limit(struct regulator_dev *rdev);
88 static unsigned int _regulator_get_mode(struct regulator_dev *rdev);
89 static int _notifier_call_chain(struct regulator_dev *rdev,
90 				  unsigned long event, void *data);
91 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
92 				     int min_uV, int max_uV);
93 static int regulator_balance_voltage(struct regulator_dev *rdev,
94 				     suspend_state_t state);
95 static struct regulator *create_regulator(struct regulator_dev *rdev,
96 					  struct device *dev,
97 					  const char *supply_name);
98 static void destroy_regulator(struct regulator *regulator);
99 static void _regulator_put(struct regulator *regulator);
100 
101 const char *rdev_get_name(struct regulator_dev *rdev)
102 {
103 	if (rdev->constraints && rdev->constraints->name)
104 		return rdev->constraints->name;
105 	else if (rdev->desc->name)
106 		return rdev->desc->name;
107 	else
108 		return "";
109 }
110 EXPORT_SYMBOL_GPL(rdev_get_name);
111 
112 static bool have_full_constraints(void)
113 {
114 	return has_full_constraints || of_have_populated_dt();
115 }
116 
117 static bool regulator_ops_is_valid(struct regulator_dev *rdev, int ops)
118 {
119 	if (!rdev->constraints) {
120 		rdev_err(rdev, "no constraints\n");
121 		return false;
122 	}
123 
124 	if (rdev->constraints->valid_ops_mask & ops)
125 		return true;
126 
127 	return false;
128 }
129 
130 /**
131  * regulator_lock_nested - lock a single regulator
132  * @rdev:		regulator source
133  * @ww_ctx:		w/w mutex acquire context
134  *
135  * This function can be called many times by one task on
136  * a single regulator and its mutex will be locked only
137  * once. If a task, which is calling this function is other
138  * than the one, which initially locked the mutex, it will
139  * wait on mutex.
140  */
141 static inline int regulator_lock_nested(struct regulator_dev *rdev,
142 					struct ww_acquire_ctx *ww_ctx)
143 {
144 	bool lock = false;
145 	int ret = 0;
146 
147 	mutex_lock(&regulator_nesting_mutex);
148 
149 	if (!ww_mutex_trylock(&rdev->mutex, ww_ctx)) {
150 		if (rdev->mutex_owner == current)
151 			rdev->ref_cnt++;
152 		else
153 			lock = true;
154 
155 		if (lock) {
156 			mutex_unlock(&regulator_nesting_mutex);
157 			ret = ww_mutex_lock(&rdev->mutex, ww_ctx);
158 			mutex_lock(&regulator_nesting_mutex);
159 		}
160 	} else {
161 		lock = true;
162 	}
163 
164 	if (lock && ret != -EDEADLK) {
165 		rdev->ref_cnt++;
166 		rdev->mutex_owner = current;
167 	}
168 
169 	mutex_unlock(&regulator_nesting_mutex);
170 
171 	return ret;
172 }
173 
174 /**
175  * regulator_lock - lock a single regulator
176  * @rdev:		regulator source
177  *
178  * This function can be called many times by one task on
179  * a single regulator and its mutex will be locked only
180  * once. If a task, which is calling this function is other
181  * than the one, which initially locked the mutex, it will
182  * wait on mutex.
183  */
184 static void regulator_lock(struct regulator_dev *rdev)
185 {
186 	regulator_lock_nested(rdev, NULL);
187 }
188 
189 /**
190  * regulator_unlock - unlock a single regulator
191  * @rdev:		regulator_source
192  *
193  * This function unlocks the mutex when the
194  * reference counter reaches 0.
195  */
196 static void regulator_unlock(struct regulator_dev *rdev)
197 {
198 	mutex_lock(&regulator_nesting_mutex);
199 
200 	if (--rdev->ref_cnt == 0) {
201 		rdev->mutex_owner = NULL;
202 		ww_mutex_unlock(&rdev->mutex);
203 	}
204 
205 	WARN_ON_ONCE(rdev->ref_cnt < 0);
206 
207 	mutex_unlock(&regulator_nesting_mutex);
208 }
209 
210 static bool regulator_supply_is_couple(struct regulator_dev *rdev)
211 {
212 	struct regulator_dev *c_rdev;
213 	int i;
214 
215 	for (i = 1; i < rdev->coupling_desc.n_coupled; i++) {
216 		c_rdev = rdev->coupling_desc.coupled_rdevs[i];
217 
218 		if (rdev->supply->rdev == c_rdev)
219 			return true;
220 	}
221 
222 	return false;
223 }
224 
225 static void regulator_unlock_recursive(struct regulator_dev *rdev,
226 				       unsigned int n_coupled)
227 {
228 	struct regulator_dev *c_rdev, *supply_rdev;
229 	int i, supply_n_coupled;
230 
231 	for (i = n_coupled; i > 0; i--) {
232 		c_rdev = rdev->coupling_desc.coupled_rdevs[i - 1];
233 
234 		if (!c_rdev)
235 			continue;
236 
237 		if (c_rdev->supply && !regulator_supply_is_couple(c_rdev)) {
238 			supply_rdev = c_rdev->supply->rdev;
239 			supply_n_coupled = supply_rdev->coupling_desc.n_coupled;
240 
241 			regulator_unlock_recursive(supply_rdev,
242 						   supply_n_coupled);
243 		}
244 
245 		regulator_unlock(c_rdev);
246 	}
247 }
248 
249 static int regulator_lock_recursive(struct regulator_dev *rdev,
250 				    struct regulator_dev **new_contended_rdev,
251 				    struct regulator_dev **old_contended_rdev,
252 				    struct ww_acquire_ctx *ww_ctx)
253 {
254 	struct regulator_dev *c_rdev;
255 	int i, err;
256 
257 	for (i = 0; i < rdev->coupling_desc.n_coupled; i++) {
258 		c_rdev = rdev->coupling_desc.coupled_rdevs[i];
259 
260 		if (!c_rdev)
261 			continue;
262 
263 		if (c_rdev != *old_contended_rdev) {
264 			err = regulator_lock_nested(c_rdev, ww_ctx);
265 			if (err) {
266 				if (err == -EDEADLK) {
267 					*new_contended_rdev = c_rdev;
268 					goto err_unlock;
269 				}
270 
271 				/* shouldn't happen */
272 				WARN_ON_ONCE(err != -EALREADY);
273 			}
274 		} else {
275 			*old_contended_rdev = NULL;
276 		}
277 
278 		if (c_rdev->supply && !regulator_supply_is_couple(c_rdev)) {
279 			err = regulator_lock_recursive(c_rdev->supply->rdev,
280 						       new_contended_rdev,
281 						       old_contended_rdev,
282 						       ww_ctx);
283 			if (err) {
284 				regulator_unlock(c_rdev);
285 				goto err_unlock;
286 			}
287 		}
288 	}
289 
290 	return 0;
291 
292 err_unlock:
293 	regulator_unlock_recursive(rdev, i);
294 
295 	return err;
296 }
297 
298 /**
299  * regulator_unlock_dependent - unlock regulator's suppliers and coupled
300  *				regulators
301  * @rdev:			regulator source
302  * @ww_ctx:			w/w mutex acquire context
303  *
304  * Unlock all regulators related with rdev by coupling or supplying.
305  */
306 static void regulator_unlock_dependent(struct regulator_dev *rdev,
307 				       struct ww_acquire_ctx *ww_ctx)
308 {
309 	regulator_unlock_recursive(rdev, rdev->coupling_desc.n_coupled);
310 	ww_acquire_fini(ww_ctx);
311 }
312 
313 /**
314  * regulator_lock_dependent - lock regulator's suppliers and coupled regulators
315  * @rdev:			regulator source
316  * @ww_ctx:			w/w mutex acquire context
317  *
318  * This function as a wrapper on regulator_lock_recursive(), which locks
319  * all regulators related with rdev by coupling or supplying.
320  */
321 static void regulator_lock_dependent(struct regulator_dev *rdev,
322 				     struct ww_acquire_ctx *ww_ctx)
323 {
324 	struct regulator_dev *new_contended_rdev = NULL;
325 	struct regulator_dev *old_contended_rdev = NULL;
326 	int err;
327 
328 	mutex_lock(&regulator_list_mutex);
329 
330 	ww_acquire_init(ww_ctx, &regulator_ww_class);
331 
332 	do {
333 		if (new_contended_rdev) {
334 			ww_mutex_lock_slow(&new_contended_rdev->mutex, ww_ctx);
335 			old_contended_rdev = new_contended_rdev;
336 			old_contended_rdev->ref_cnt++;
337 		}
338 
339 		err = regulator_lock_recursive(rdev,
340 					       &new_contended_rdev,
341 					       &old_contended_rdev,
342 					       ww_ctx);
343 
344 		if (old_contended_rdev)
345 			regulator_unlock(old_contended_rdev);
346 
347 	} while (err == -EDEADLK);
348 
349 	ww_acquire_done(ww_ctx);
350 
351 	mutex_unlock(&regulator_list_mutex);
352 }
353 
354 /**
355  * of_get_child_regulator - get a child regulator device node
356  * based on supply name
357  * @parent: Parent device node
358  * @prop_name: Combination regulator supply name and "-supply"
359  *
360  * Traverse all child nodes.
361  * Extract the child regulator device node corresponding to the supply name.
362  * returns the device node corresponding to the regulator if found, else
363  * returns NULL.
364  */
365 static struct device_node *of_get_child_regulator(struct device_node *parent,
366 						  const char *prop_name)
367 {
368 	struct device_node *regnode = NULL;
369 	struct device_node *child = NULL;
370 
371 	for_each_child_of_node(parent, child) {
372 		regnode = of_parse_phandle(child, prop_name, 0);
373 
374 		if (!regnode) {
375 			regnode = of_get_child_regulator(child, prop_name);
376 			if (regnode)
377 				goto err_node_put;
378 		} else {
379 			goto err_node_put;
380 		}
381 	}
382 	return NULL;
383 
384 err_node_put:
385 	of_node_put(child);
386 	return regnode;
387 }
388 
389 /**
390  * of_get_regulator - get a regulator device node based on supply name
391  * @dev: Device pointer for the consumer (of regulator) device
392  * @supply: regulator supply name
393  *
394  * Extract the regulator device node corresponding to the supply name.
395  * returns the device node corresponding to the regulator if found, else
396  * returns NULL.
397  */
398 static struct device_node *of_get_regulator(struct device *dev, const char *supply)
399 {
400 	struct device_node *regnode = NULL;
401 	char prop_name[64]; /* 64 is max size of property name */
402 
403 	dev_dbg(dev, "Looking up %s-supply from device tree\n", supply);
404 
405 	snprintf(prop_name, 64, "%s-supply", supply);
406 	regnode = of_parse_phandle(dev->of_node, prop_name, 0);
407 
408 	if (!regnode) {
409 		regnode = of_get_child_regulator(dev->of_node, prop_name);
410 		if (regnode)
411 			return regnode;
412 
413 		dev_dbg(dev, "Looking up %s property in node %pOF failed\n",
414 				prop_name, dev->of_node);
415 		return NULL;
416 	}
417 	return regnode;
418 }
419 
420 /* Platform voltage constraint check */
421 int regulator_check_voltage(struct regulator_dev *rdev,
422 			    int *min_uV, int *max_uV)
423 {
424 	BUG_ON(*min_uV > *max_uV);
425 
426 	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE)) {
427 		rdev_err(rdev, "voltage operation not allowed\n");
428 		return -EPERM;
429 	}
430 
431 	if (*max_uV > rdev->constraints->max_uV)
432 		*max_uV = rdev->constraints->max_uV;
433 	if (*min_uV < rdev->constraints->min_uV)
434 		*min_uV = rdev->constraints->min_uV;
435 
436 	if (*min_uV > *max_uV) {
437 		rdev_err(rdev, "unsupportable voltage range: %d-%duV\n",
438 			 *min_uV, *max_uV);
439 		return -EINVAL;
440 	}
441 
442 	return 0;
443 }
444 
445 /* return 0 if the state is valid */
446 static int regulator_check_states(suspend_state_t state)
447 {
448 	return (state > PM_SUSPEND_MAX || state == PM_SUSPEND_TO_IDLE);
449 }
450 
451 /* Make sure we select a voltage that suits the needs of all
452  * regulator consumers
453  */
454 int regulator_check_consumers(struct regulator_dev *rdev,
455 			      int *min_uV, int *max_uV,
456 			      suspend_state_t state)
457 {
458 	struct regulator *regulator;
459 	struct regulator_voltage *voltage;
460 
461 	list_for_each_entry(regulator, &rdev->consumer_list, list) {
462 		voltage = &regulator->voltage[state];
463 		/*
464 		 * Assume consumers that didn't say anything are OK
465 		 * with anything in the constraint range.
466 		 */
467 		if (!voltage->min_uV && !voltage->max_uV)
468 			continue;
469 
470 		if (*max_uV > voltage->max_uV)
471 			*max_uV = voltage->max_uV;
472 		if (*min_uV < voltage->min_uV)
473 			*min_uV = voltage->min_uV;
474 	}
475 
476 	if (*min_uV > *max_uV) {
477 		rdev_err(rdev, "Restricting voltage, %u-%uuV\n",
478 			*min_uV, *max_uV);
479 		return -EINVAL;
480 	}
481 
482 	return 0;
483 }
484 
485 /* current constraint check */
486 static int regulator_check_current_limit(struct regulator_dev *rdev,
487 					int *min_uA, int *max_uA)
488 {
489 	BUG_ON(*min_uA > *max_uA);
490 
491 	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_CURRENT)) {
492 		rdev_err(rdev, "current operation not allowed\n");
493 		return -EPERM;
494 	}
495 
496 	if (*max_uA > rdev->constraints->max_uA)
497 		*max_uA = rdev->constraints->max_uA;
498 	if (*min_uA < rdev->constraints->min_uA)
499 		*min_uA = rdev->constraints->min_uA;
500 
501 	if (*min_uA > *max_uA) {
502 		rdev_err(rdev, "unsupportable current range: %d-%duA\n",
503 			 *min_uA, *max_uA);
504 		return -EINVAL;
505 	}
506 
507 	return 0;
508 }
509 
510 /* operating mode constraint check */
511 static int regulator_mode_constrain(struct regulator_dev *rdev,
512 				    unsigned int *mode)
513 {
514 	switch (*mode) {
515 	case REGULATOR_MODE_FAST:
516 	case REGULATOR_MODE_NORMAL:
517 	case REGULATOR_MODE_IDLE:
518 	case REGULATOR_MODE_STANDBY:
519 		break;
520 	default:
521 		rdev_err(rdev, "invalid mode %x specified\n", *mode);
522 		return -EINVAL;
523 	}
524 
525 	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_MODE)) {
526 		rdev_err(rdev, "mode operation not allowed\n");
527 		return -EPERM;
528 	}
529 
530 	/* The modes are bitmasks, the most power hungry modes having
531 	 * the lowest values. If the requested mode isn't supported
532 	 * try higher modes.
533 	 */
534 	while (*mode) {
535 		if (rdev->constraints->valid_modes_mask & *mode)
536 			return 0;
537 		*mode /= 2;
538 	}
539 
540 	return -EINVAL;
541 }
542 
543 static inline struct regulator_state *
544 regulator_get_suspend_state(struct regulator_dev *rdev, suspend_state_t state)
545 {
546 	if (rdev->constraints == NULL)
547 		return NULL;
548 
549 	switch (state) {
550 	case PM_SUSPEND_STANDBY:
551 		return &rdev->constraints->state_standby;
552 	case PM_SUSPEND_MEM:
553 		return &rdev->constraints->state_mem;
554 	case PM_SUSPEND_MAX:
555 		return &rdev->constraints->state_disk;
556 	default:
557 		return NULL;
558 	}
559 }
560 
561 static const struct regulator_state *
562 regulator_get_suspend_state_check(struct regulator_dev *rdev, suspend_state_t state)
563 {
564 	const struct regulator_state *rstate;
565 
566 	rstate = regulator_get_suspend_state(rdev, state);
567 	if (rstate == NULL)
568 		return NULL;
569 
570 	/* If we have no suspend mode configuration don't set anything;
571 	 * only warn if the driver implements set_suspend_voltage or
572 	 * set_suspend_mode callback.
573 	 */
574 	if (rstate->enabled != ENABLE_IN_SUSPEND &&
575 	    rstate->enabled != DISABLE_IN_SUSPEND) {
576 		if (rdev->desc->ops->set_suspend_voltage ||
577 		    rdev->desc->ops->set_suspend_mode)
578 			rdev_warn(rdev, "No configuration\n");
579 		return NULL;
580 	}
581 
582 	return rstate;
583 }
584 
585 static ssize_t microvolts_show(struct device *dev,
586 			       struct device_attribute *attr, char *buf)
587 {
588 	struct regulator_dev *rdev = dev_get_drvdata(dev);
589 	int uV;
590 
591 	regulator_lock(rdev);
592 	uV = regulator_get_voltage_rdev(rdev);
593 	regulator_unlock(rdev);
594 
595 	if (uV < 0)
596 		return uV;
597 	return sprintf(buf, "%d\n", uV);
598 }
599 static DEVICE_ATTR_RO(microvolts);
600 
601 static ssize_t microamps_show(struct device *dev,
602 			      struct device_attribute *attr, char *buf)
603 {
604 	struct regulator_dev *rdev = dev_get_drvdata(dev);
605 
606 	return sprintf(buf, "%d\n", _regulator_get_current_limit(rdev));
607 }
608 static DEVICE_ATTR_RO(microamps);
609 
610 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
611 			 char *buf)
612 {
613 	struct regulator_dev *rdev = dev_get_drvdata(dev);
614 
615 	return sprintf(buf, "%s\n", rdev_get_name(rdev));
616 }
617 static DEVICE_ATTR_RO(name);
618 
619 static const char *regulator_opmode_to_str(int mode)
620 {
621 	switch (mode) {
622 	case REGULATOR_MODE_FAST:
623 		return "fast";
624 	case REGULATOR_MODE_NORMAL:
625 		return "normal";
626 	case REGULATOR_MODE_IDLE:
627 		return "idle";
628 	case REGULATOR_MODE_STANDBY:
629 		return "standby";
630 	}
631 	return "unknown";
632 }
633 
634 static ssize_t regulator_print_opmode(char *buf, int mode)
635 {
636 	return sprintf(buf, "%s\n", regulator_opmode_to_str(mode));
637 }
638 
639 static ssize_t opmode_show(struct device *dev,
640 			   struct device_attribute *attr, char *buf)
641 {
642 	struct regulator_dev *rdev = dev_get_drvdata(dev);
643 
644 	return regulator_print_opmode(buf, _regulator_get_mode(rdev));
645 }
646 static DEVICE_ATTR_RO(opmode);
647 
648 static ssize_t regulator_print_state(char *buf, int state)
649 {
650 	if (state > 0)
651 		return sprintf(buf, "enabled\n");
652 	else if (state == 0)
653 		return sprintf(buf, "disabled\n");
654 	else
655 		return sprintf(buf, "unknown\n");
656 }
657 
658 static ssize_t state_show(struct device *dev,
659 			  struct device_attribute *attr, char *buf)
660 {
661 	struct regulator_dev *rdev = dev_get_drvdata(dev);
662 	ssize_t ret;
663 
664 	regulator_lock(rdev);
665 	ret = regulator_print_state(buf, _regulator_is_enabled(rdev));
666 	regulator_unlock(rdev);
667 
668 	return ret;
669 }
670 static DEVICE_ATTR_RO(state);
671 
672 static ssize_t status_show(struct device *dev,
673 			   struct device_attribute *attr, char *buf)
674 {
675 	struct regulator_dev *rdev = dev_get_drvdata(dev);
676 	int status;
677 	char *label;
678 
679 	status = rdev->desc->ops->get_status(rdev);
680 	if (status < 0)
681 		return status;
682 
683 	switch (status) {
684 	case REGULATOR_STATUS_OFF:
685 		label = "off";
686 		break;
687 	case REGULATOR_STATUS_ON:
688 		label = "on";
689 		break;
690 	case REGULATOR_STATUS_ERROR:
691 		label = "error";
692 		break;
693 	case REGULATOR_STATUS_FAST:
694 		label = "fast";
695 		break;
696 	case REGULATOR_STATUS_NORMAL:
697 		label = "normal";
698 		break;
699 	case REGULATOR_STATUS_IDLE:
700 		label = "idle";
701 		break;
702 	case REGULATOR_STATUS_STANDBY:
703 		label = "standby";
704 		break;
705 	case REGULATOR_STATUS_BYPASS:
706 		label = "bypass";
707 		break;
708 	case REGULATOR_STATUS_UNDEFINED:
709 		label = "undefined";
710 		break;
711 	default:
712 		return -ERANGE;
713 	}
714 
715 	return sprintf(buf, "%s\n", label);
716 }
717 static DEVICE_ATTR_RO(status);
718 
719 static ssize_t min_microamps_show(struct device *dev,
720 				  struct device_attribute *attr, char *buf)
721 {
722 	struct regulator_dev *rdev = dev_get_drvdata(dev);
723 
724 	if (!rdev->constraints)
725 		return sprintf(buf, "constraint not defined\n");
726 
727 	return sprintf(buf, "%d\n", rdev->constraints->min_uA);
728 }
729 static DEVICE_ATTR_RO(min_microamps);
730 
731 static ssize_t max_microamps_show(struct device *dev,
732 				  struct device_attribute *attr, char *buf)
733 {
734 	struct regulator_dev *rdev = dev_get_drvdata(dev);
735 
736 	if (!rdev->constraints)
737 		return sprintf(buf, "constraint not defined\n");
738 
739 	return sprintf(buf, "%d\n", rdev->constraints->max_uA);
740 }
741 static DEVICE_ATTR_RO(max_microamps);
742 
743 static ssize_t min_microvolts_show(struct device *dev,
744 				   struct device_attribute *attr, char *buf)
745 {
746 	struct regulator_dev *rdev = dev_get_drvdata(dev);
747 
748 	if (!rdev->constraints)
749 		return sprintf(buf, "constraint not defined\n");
750 
751 	return sprintf(buf, "%d\n", rdev->constraints->min_uV);
752 }
753 static DEVICE_ATTR_RO(min_microvolts);
754 
755 static ssize_t max_microvolts_show(struct device *dev,
756 				   struct device_attribute *attr, char *buf)
757 {
758 	struct regulator_dev *rdev = dev_get_drvdata(dev);
759 
760 	if (!rdev->constraints)
761 		return sprintf(buf, "constraint not defined\n");
762 
763 	return sprintf(buf, "%d\n", rdev->constraints->max_uV);
764 }
765 static DEVICE_ATTR_RO(max_microvolts);
766 
767 static ssize_t requested_microamps_show(struct device *dev,
768 					struct device_attribute *attr, char *buf)
769 {
770 	struct regulator_dev *rdev = dev_get_drvdata(dev);
771 	struct regulator *regulator;
772 	int uA = 0;
773 
774 	regulator_lock(rdev);
775 	list_for_each_entry(regulator, &rdev->consumer_list, list) {
776 		if (regulator->enable_count)
777 			uA += regulator->uA_load;
778 	}
779 	regulator_unlock(rdev);
780 	return sprintf(buf, "%d\n", uA);
781 }
782 static DEVICE_ATTR_RO(requested_microamps);
783 
784 static ssize_t num_users_show(struct device *dev, struct device_attribute *attr,
785 			      char *buf)
786 {
787 	struct regulator_dev *rdev = dev_get_drvdata(dev);
788 	return sprintf(buf, "%d\n", rdev->use_count);
789 }
790 static DEVICE_ATTR_RO(num_users);
791 
792 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
793 			 char *buf)
794 {
795 	struct regulator_dev *rdev = dev_get_drvdata(dev);
796 
797 	switch (rdev->desc->type) {
798 	case REGULATOR_VOLTAGE:
799 		return sprintf(buf, "voltage\n");
800 	case REGULATOR_CURRENT:
801 		return sprintf(buf, "current\n");
802 	}
803 	return sprintf(buf, "unknown\n");
804 }
805 static DEVICE_ATTR_RO(type);
806 
807 static ssize_t suspend_mem_microvolts_show(struct device *dev,
808 					   struct device_attribute *attr, char *buf)
809 {
810 	struct regulator_dev *rdev = dev_get_drvdata(dev);
811 
812 	return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
813 }
814 static DEVICE_ATTR_RO(suspend_mem_microvolts);
815 
816 static ssize_t suspend_disk_microvolts_show(struct device *dev,
817 					    struct device_attribute *attr, char *buf)
818 {
819 	struct regulator_dev *rdev = dev_get_drvdata(dev);
820 
821 	return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
822 }
823 static DEVICE_ATTR_RO(suspend_disk_microvolts);
824 
825 static ssize_t suspend_standby_microvolts_show(struct device *dev,
826 					       struct device_attribute *attr, char *buf)
827 {
828 	struct regulator_dev *rdev = dev_get_drvdata(dev);
829 
830 	return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
831 }
832 static DEVICE_ATTR_RO(suspend_standby_microvolts);
833 
834 static ssize_t suspend_mem_mode_show(struct device *dev,
835 				     struct device_attribute *attr, char *buf)
836 {
837 	struct regulator_dev *rdev = dev_get_drvdata(dev);
838 
839 	return regulator_print_opmode(buf,
840 		rdev->constraints->state_mem.mode);
841 }
842 static DEVICE_ATTR_RO(suspend_mem_mode);
843 
844 static ssize_t suspend_disk_mode_show(struct device *dev,
845 				      struct device_attribute *attr, char *buf)
846 {
847 	struct regulator_dev *rdev = dev_get_drvdata(dev);
848 
849 	return regulator_print_opmode(buf,
850 		rdev->constraints->state_disk.mode);
851 }
852 static DEVICE_ATTR_RO(suspend_disk_mode);
853 
854 static ssize_t suspend_standby_mode_show(struct device *dev,
855 					 struct device_attribute *attr, char *buf)
856 {
857 	struct regulator_dev *rdev = dev_get_drvdata(dev);
858 
859 	return regulator_print_opmode(buf,
860 		rdev->constraints->state_standby.mode);
861 }
862 static DEVICE_ATTR_RO(suspend_standby_mode);
863 
864 static ssize_t suspend_mem_state_show(struct device *dev,
865 				      struct device_attribute *attr, char *buf)
866 {
867 	struct regulator_dev *rdev = dev_get_drvdata(dev);
868 
869 	return regulator_print_state(buf,
870 			rdev->constraints->state_mem.enabled);
871 }
872 static DEVICE_ATTR_RO(suspend_mem_state);
873 
874 static ssize_t suspend_disk_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_disk.enabled);
881 }
882 static DEVICE_ATTR_RO(suspend_disk_state);
883 
884 static ssize_t suspend_standby_state_show(struct device *dev,
885 					  struct device_attribute *attr, char *buf)
886 {
887 	struct regulator_dev *rdev = dev_get_drvdata(dev);
888 
889 	return regulator_print_state(buf,
890 			rdev->constraints->state_standby.enabled);
891 }
892 static DEVICE_ATTR_RO(suspend_standby_state);
893 
894 static ssize_t bypass_show(struct device *dev,
895 			   struct device_attribute *attr, char *buf)
896 {
897 	struct regulator_dev *rdev = dev_get_drvdata(dev);
898 	const char *report;
899 	bool bypass;
900 	int ret;
901 
902 	ret = rdev->desc->ops->get_bypass(rdev, &bypass);
903 
904 	if (ret != 0)
905 		report = "unknown";
906 	else if (bypass)
907 		report = "enabled";
908 	else
909 		report = "disabled";
910 
911 	return sprintf(buf, "%s\n", report);
912 }
913 static DEVICE_ATTR_RO(bypass);
914 
915 #define REGULATOR_ERROR_ATTR(name, bit)							\
916 	static ssize_t name##_show(struct device *dev, struct device_attribute *attr,	\
917 				   char *buf)						\
918 	{										\
919 		int ret;								\
920 		unsigned int flags;							\
921 		struct regulator_dev *rdev = dev_get_drvdata(dev);			\
922 		ret = _regulator_get_error_flags(rdev, &flags);				\
923 		if (ret)								\
924 			return ret;							\
925 		return sysfs_emit(buf, "%d\n", !!(flags & (bit)));			\
926 	}										\
927 	static DEVICE_ATTR_RO(name)
928 
929 REGULATOR_ERROR_ATTR(under_voltage, REGULATOR_ERROR_UNDER_VOLTAGE);
930 REGULATOR_ERROR_ATTR(over_current, REGULATOR_ERROR_OVER_CURRENT);
931 REGULATOR_ERROR_ATTR(regulation_out, REGULATOR_ERROR_REGULATION_OUT);
932 REGULATOR_ERROR_ATTR(fail, REGULATOR_ERROR_FAIL);
933 REGULATOR_ERROR_ATTR(over_temp, REGULATOR_ERROR_OVER_TEMP);
934 REGULATOR_ERROR_ATTR(under_voltage_warn, REGULATOR_ERROR_UNDER_VOLTAGE_WARN);
935 REGULATOR_ERROR_ATTR(over_current_warn, REGULATOR_ERROR_OVER_CURRENT_WARN);
936 REGULATOR_ERROR_ATTR(over_voltage_warn, REGULATOR_ERROR_OVER_VOLTAGE_WARN);
937 REGULATOR_ERROR_ATTR(over_temp_warn, REGULATOR_ERROR_OVER_TEMP_WARN);
938 
939 /* Calculate the new optimum regulator operating mode based on the new total
940  * consumer load. All locks held by caller
941  */
942 static int drms_uA_update(struct regulator_dev *rdev)
943 {
944 	struct regulator *sibling;
945 	int current_uA = 0, output_uV, input_uV, err;
946 	unsigned int mode;
947 
948 	/*
949 	 * first check to see if we can set modes at all, otherwise just
950 	 * tell the consumer everything is OK.
951 	 */
952 	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_DRMS)) {
953 		rdev_dbg(rdev, "DRMS operation not allowed\n");
954 		return 0;
955 	}
956 
957 	if (!rdev->desc->ops->get_optimum_mode &&
958 	    !rdev->desc->ops->set_load)
959 		return 0;
960 
961 	if (!rdev->desc->ops->set_mode &&
962 	    !rdev->desc->ops->set_load)
963 		return -EINVAL;
964 
965 	/* calc total requested load */
966 	list_for_each_entry(sibling, &rdev->consumer_list, list) {
967 		if (sibling->enable_count)
968 			current_uA += sibling->uA_load;
969 	}
970 
971 	current_uA += rdev->constraints->system_load;
972 
973 	if (rdev->desc->ops->set_load) {
974 		/* set the optimum mode for our new total regulator load */
975 		err = rdev->desc->ops->set_load(rdev, current_uA);
976 		if (err < 0)
977 			rdev_err(rdev, "failed to set load %d: %pe\n",
978 				 current_uA, ERR_PTR(err));
979 	} else {
980 		/*
981 		 * Unfortunately in some cases the constraints->valid_ops has
982 		 * REGULATOR_CHANGE_DRMS but there are no valid modes listed.
983 		 * That's not really legit but we won't consider it a fatal
984 		 * error here. We'll treat it as if REGULATOR_CHANGE_DRMS
985 		 * wasn't set.
986 		 */
987 		if (!rdev->constraints->valid_modes_mask) {
988 			rdev_dbg(rdev, "Can change modes; but no valid mode\n");
989 			return 0;
990 		}
991 
992 		/* get output voltage */
993 		output_uV = regulator_get_voltage_rdev(rdev);
994 
995 		/*
996 		 * Don't return an error; if regulator driver cares about
997 		 * output_uV then it's up to the driver to validate.
998 		 */
999 		if (output_uV <= 0)
1000 			rdev_dbg(rdev, "invalid output voltage found\n");
1001 
1002 		/* get input voltage */
1003 		input_uV = 0;
1004 		if (rdev->supply)
1005 			input_uV = regulator_get_voltage_rdev(rdev->supply->rdev);
1006 		if (input_uV <= 0)
1007 			input_uV = rdev->constraints->input_uV;
1008 
1009 		/*
1010 		 * Don't return an error; if regulator driver cares about
1011 		 * input_uV then it's up to the driver to validate.
1012 		 */
1013 		if (input_uV <= 0)
1014 			rdev_dbg(rdev, "invalid input voltage found\n");
1015 
1016 		/* now get the optimum mode for our new total regulator load */
1017 		mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
1018 							 output_uV, current_uA);
1019 
1020 		/* check the new mode is allowed */
1021 		err = regulator_mode_constrain(rdev, &mode);
1022 		if (err < 0) {
1023 			rdev_err(rdev, "failed to get optimum mode @ %d uA %d -> %d uV: %pe\n",
1024 				 current_uA, input_uV, output_uV, ERR_PTR(err));
1025 			return err;
1026 		}
1027 
1028 		err = rdev->desc->ops->set_mode(rdev, mode);
1029 		if (err < 0)
1030 			rdev_err(rdev, "failed to set optimum mode %x: %pe\n",
1031 				 mode, ERR_PTR(err));
1032 	}
1033 
1034 	return err;
1035 }
1036 
1037 static int __suspend_set_state(struct regulator_dev *rdev,
1038 			       const struct regulator_state *rstate)
1039 {
1040 	int ret = 0;
1041 
1042 	if (rstate->enabled == ENABLE_IN_SUSPEND &&
1043 		rdev->desc->ops->set_suspend_enable)
1044 		ret = rdev->desc->ops->set_suspend_enable(rdev);
1045 	else if (rstate->enabled == DISABLE_IN_SUSPEND &&
1046 		rdev->desc->ops->set_suspend_disable)
1047 		ret = rdev->desc->ops->set_suspend_disable(rdev);
1048 	else /* OK if set_suspend_enable or set_suspend_disable is NULL */
1049 		ret = 0;
1050 
1051 	if (ret < 0) {
1052 		rdev_err(rdev, "failed to enabled/disable: %pe\n", ERR_PTR(ret));
1053 		return ret;
1054 	}
1055 
1056 	if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
1057 		ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
1058 		if (ret < 0) {
1059 			rdev_err(rdev, "failed to set voltage: %pe\n", ERR_PTR(ret));
1060 			return ret;
1061 		}
1062 	}
1063 
1064 	if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
1065 		ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
1066 		if (ret < 0) {
1067 			rdev_err(rdev, "failed to set mode: %pe\n", ERR_PTR(ret));
1068 			return ret;
1069 		}
1070 	}
1071 
1072 	return ret;
1073 }
1074 
1075 static int suspend_set_initial_state(struct regulator_dev *rdev)
1076 {
1077 	const struct regulator_state *rstate;
1078 
1079 	rstate = regulator_get_suspend_state_check(rdev,
1080 			rdev->constraints->initial_state);
1081 	if (!rstate)
1082 		return 0;
1083 
1084 	return __suspend_set_state(rdev, rstate);
1085 }
1086 
1087 #if defined(DEBUG) || defined(CONFIG_DYNAMIC_DEBUG)
1088 static void print_constraints_debug(struct regulator_dev *rdev)
1089 {
1090 	struct regulation_constraints *constraints = rdev->constraints;
1091 	char buf[160] = "";
1092 	size_t len = sizeof(buf) - 1;
1093 	int count = 0;
1094 	int ret;
1095 
1096 	if (constraints->min_uV && constraints->max_uV) {
1097 		if (constraints->min_uV == constraints->max_uV)
1098 			count += scnprintf(buf + count, len - count, "%d mV ",
1099 					   constraints->min_uV / 1000);
1100 		else
1101 			count += scnprintf(buf + count, len - count,
1102 					   "%d <--> %d mV ",
1103 					   constraints->min_uV / 1000,
1104 					   constraints->max_uV / 1000);
1105 	}
1106 
1107 	if (!constraints->min_uV ||
1108 	    constraints->min_uV != constraints->max_uV) {
1109 		ret = regulator_get_voltage_rdev(rdev);
1110 		if (ret > 0)
1111 			count += scnprintf(buf + count, len - count,
1112 					   "at %d mV ", ret / 1000);
1113 	}
1114 
1115 	if (constraints->uV_offset)
1116 		count += scnprintf(buf + count, len - count, "%dmV offset ",
1117 				   constraints->uV_offset / 1000);
1118 
1119 	if (constraints->min_uA && constraints->max_uA) {
1120 		if (constraints->min_uA == constraints->max_uA)
1121 			count += scnprintf(buf + count, len - count, "%d mA ",
1122 					   constraints->min_uA / 1000);
1123 		else
1124 			count += scnprintf(buf + count, len - count,
1125 					   "%d <--> %d mA ",
1126 					   constraints->min_uA / 1000,
1127 					   constraints->max_uA / 1000);
1128 	}
1129 
1130 	if (!constraints->min_uA ||
1131 	    constraints->min_uA != constraints->max_uA) {
1132 		ret = _regulator_get_current_limit(rdev);
1133 		if (ret > 0)
1134 			count += scnprintf(buf + count, len - count,
1135 					   "at %d mA ", ret / 1000);
1136 	}
1137 
1138 	if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
1139 		count += scnprintf(buf + count, len - count, "fast ");
1140 	if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
1141 		count += scnprintf(buf + count, len - count, "normal ");
1142 	if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
1143 		count += scnprintf(buf + count, len - count, "idle ");
1144 	if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
1145 		count += scnprintf(buf + count, len - count, "standby ");
1146 
1147 	if (!count)
1148 		count = scnprintf(buf, len, "no parameters");
1149 	else
1150 		--count;
1151 
1152 	count += scnprintf(buf + count, len - count, ", %s",
1153 		_regulator_is_enabled(rdev) ? "enabled" : "disabled");
1154 
1155 	rdev_dbg(rdev, "%s\n", buf);
1156 }
1157 #else /* !DEBUG && !CONFIG_DYNAMIC_DEBUG */
1158 static inline void print_constraints_debug(struct regulator_dev *rdev) {}
1159 #endif /* !DEBUG && !CONFIG_DYNAMIC_DEBUG */
1160 
1161 static void print_constraints(struct regulator_dev *rdev)
1162 {
1163 	struct regulation_constraints *constraints = rdev->constraints;
1164 
1165 	print_constraints_debug(rdev);
1166 
1167 	if ((constraints->min_uV != constraints->max_uV) &&
1168 	    !regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE))
1169 		rdev_warn(rdev,
1170 			  "Voltage range but no REGULATOR_CHANGE_VOLTAGE\n");
1171 }
1172 
1173 static int machine_constraints_voltage(struct regulator_dev *rdev,
1174 	struct regulation_constraints *constraints)
1175 {
1176 	const struct regulator_ops *ops = rdev->desc->ops;
1177 	int ret;
1178 
1179 	/* do we need to apply the constraint voltage */
1180 	if (rdev->constraints->apply_uV &&
1181 	    rdev->constraints->min_uV && rdev->constraints->max_uV) {
1182 		int target_min, target_max;
1183 		int current_uV = regulator_get_voltage_rdev(rdev);
1184 
1185 		if (current_uV == -ENOTRECOVERABLE) {
1186 			/* This regulator can't be read and must be initialized */
1187 			rdev_info(rdev, "Setting %d-%duV\n",
1188 				  rdev->constraints->min_uV,
1189 				  rdev->constraints->max_uV);
1190 			_regulator_do_set_voltage(rdev,
1191 						  rdev->constraints->min_uV,
1192 						  rdev->constraints->max_uV);
1193 			current_uV = regulator_get_voltage_rdev(rdev);
1194 		}
1195 
1196 		if (current_uV < 0) {
1197 			if (current_uV != -EPROBE_DEFER)
1198 				rdev_err(rdev,
1199 					 "failed to get the current voltage: %pe\n",
1200 					 ERR_PTR(current_uV));
1201 			return current_uV;
1202 		}
1203 
1204 		/*
1205 		 * If we're below the minimum voltage move up to the
1206 		 * minimum voltage, if we're above the maximum voltage
1207 		 * then move down to the maximum.
1208 		 */
1209 		target_min = current_uV;
1210 		target_max = current_uV;
1211 
1212 		if (current_uV < rdev->constraints->min_uV) {
1213 			target_min = rdev->constraints->min_uV;
1214 			target_max = rdev->constraints->min_uV;
1215 		}
1216 
1217 		if (current_uV > rdev->constraints->max_uV) {
1218 			target_min = rdev->constraints->max_uV;
1219 			target_max = rdev->constraints->max_uV;
1220 		}
1221 
1222 		if (target_min != current_uV || target_max != current_uV) {
1223 			rdev_info(rdev, "Bringing %duV into %d-%duV\n",
1224 				  current_uV, target_min, target_max);
1225 			ret = _regulator_do_set_voltage(
1226 				rdev, target_min, target_max);
1227 			if (ret < 0) {
1228 				rdev_err(rdev,
1229 					"failed to apply %d-%duV constraint: %pe\n",
1230 					target_min, target_max, ERR_PTR(ret));
1231 				return ret;
1232 			}
1233 		}
1234 	}
1235 
1236 	/* constrain machine-level voltage specs to fit
1237 	 * the actual range supported by this regulator.
1238 	 */
1239 	if (ops->list_voltage && rdev->desc->n_voltages) {
1240 		int	count = rdev->desc->n_voltages;
1241 		int	i;
1242 		int	min_uV = INT_MAX;
1243 		int	max_uV = INT_MIN;
1244 		int	cmin = constraints->min_uV;
1245 		int	cmax = constraints->max_uV;
1246 
1247 		/* it's safe to autoconfigure fixed-voltage supplies
1248 		 * and the constraints are used by list_voltage.
1249 		 */
1250 		if (count == 1 && !cmin) {
1251 			cmin = 1;
1252 			cmax = INT_MAX;
1253 			constraints->min_uV = cmin;
1254 			constraints->max_uV = cmax;
1255 		}
1256 
1257 		/* voltage constraints are optional */
1258 		if ((cmin == 0) && (cmax == 0))
1259 			return 0;
1260 
1261 		/* else require explicit machine-level constraints */
1262 		if (cmin <= 0 || cmax <= 0 || cmax < cmin) {
1263 			rdev_err(rdev, "invalid voltage constraints\n");
1264 			return -EINVAL;
1265 		}
1266 
1267 		/* no need to loop voltages if range is continuous */
1268 		if (rdev->desc->continuous_voltage_range)
1269 			return 0;
1270 
1271 		/* initial: [cmin..cmax] valid, [min_uV..max_uV] not */
1272 		for (i = 0; i < count; i++) {
1273 			int	value;
1274 
1275 			value = ops->list_voltage(rdev, i);
1276 			if (value <= 0)
1277 				continue;
1278 
1279 			/* maybe adjust [min_uV..max_uV] */
1280 			if (value >= cmin && value < min_uV)
1281 				min_uV = value;
1282 			if (value <= cmax && value > max_uV)
1283 				max_uV = value;
1284 		}
1285 
1286 		/* final: [min_uV..max_uV] valid iff constraints valid */
1287 		if (max_uV < min_uV) {
1288 			rdev_err(rdev,
1289 				 "unsupportable voltage constraints %u-%uuV\n",
1290 				 min_uV, max_uV);
1291 			return -EINVAL;
1292 		}
1293 
1294 		/* use regulator's subset of machine constraints */
1295 		if (constraints->min_uV < min_uV) {
1296 			rdev_dbg(rdev, "override min_uV, %d -> %d\n",
1297 				 constraints->min_uV, min_uV);
1298 			constraints->min_uV = min_uV;
1299 		}
1300 		if (constraints->max_uV > max_uV) {
1301 			rdev_dbg(rdev, "override max_uV, %d -> %d\n",
1302 				 constraints->max_uV, max_uV);
1303 			constraints->max_uV = max_uV;
1304 		}
1305 	}
1306 
1307 	return 0;
1308 }
1309 
1310 static int machine_constraints_current(struct regulator_dev *rdev,
1311 	struct regulation_constraints *constraints)
1312 {
1313 	const struct regulator_ops *ops = rdev->desc->ops;
1314 	int ret;
1315 
1316 	if (!constraints->min_uA && !constraints->max_uA)
1317 		return 0;
1318 
1319 	if (constraints->min_uA > constraints->max_uA) {
1320 		rdev_err(rdev, "Invalid current constraints\n");
1321 		return -EINVAL;
1322 	}
1323 
1324 	if (!ops->set_current_limit || !ops->get_current_limit) {
1325 		rdev_warn(rdev, "Operation of current configuration missing\n");
1326 		return 0;
1327 	}
1328 
1329 	/* Set regulator current in constraints range */
1330 	ret = ops->set_current_limit(rdev, constraints->min_uA,
1331 			constraints->max_uA);
1332 	if (ret < 0) {
1333 		rdev_err(rdev, "Failed to set current constraint, %d\n", ret);
1334 		return ret;
1335 	}
1336 
1337 	return 0;
1338 }
1339 
1340 static int _regulator_do_enable(struct regulator_dev *rdev);
1341 
1342 static int notif_set_limit(struct regulator_dev *rdev,
1343 			   int (*set)(struct regulator_dev *, int, int, bool),
1344 			   int limit, int severity)
1345 {
1346 	bool enable;
1347 
1348 	if (limit == REGULATOR_NOTIF_LIMIT_DISABLE) {
1349 		enable = false;
1350 		limit = 0;
1351 	} else {
1352 		enable = true;
1353 	}
1354 
1355 	if (limit == REGULATOR_NOTIF_LIMIT_ENABLE)
1356 		limit = 0;
1357 
1358 	return set(rdev, limit, severity, enable);
1359 }
1360 
1361 static int handle_notify_limits(struct regulator_dev *rdev,
1362 			int (*set)(struct regulator_dev *, int, int, bool),
1363 			struct notification_limit *limits)
1364 {
1365 	int ret = 0;
1366 
1367 	if (!set)
1368 		return -EOPNOTSUPP;
1369 
1370 	if (limits->prot)
1371 		ret = notif_set_limit(rdev, set, limits->prot,
1372 				      REGULATOR_SEVERITY_PROT);
1373 	if (ret)
1374 		return ret;
1375 
1376 	if (limits->err)
1377 		ret = notif_set_limit(rdev, set, limits->err,
1378 				      REGULATOR_SEVERITY_ERR);
1379 	if (ret)
1380 		return ret;
1381 
1382 	if (limits->warn)
1383 		ret = notif_set_limit(rdev, set, limits->warn,
1384 				      REGULATOR_SEVERITY_WARN);
1385 
1386 	return ret;
1387 }
1388 /**
1389  * set_machine_constraints - sets regulator constraints
1390  * @rdev: regulator source
1391  *
1392  * Allows platform initialisation code to define and constrain
1393  * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
1394  * Constraints *must* be set by platform code in order for some
1395  * regulator operations to proceed i.e. set_voltage, set_current_limit,
1396  * set_mode.
1397  */
1398 static int set_machine_constraints(struct regulator_dev *rdev)
1399 {
1400 	int ret = 0;
1401 	const struct regulator_ops *ops = rdev->desc->ops;
1402 
1403 	ret = machine_constraints_voltage(rdev, rdev->constraints);
1404 	if (ret != 0)
1405 		return ret;
1406 
1407 	ret = machine_constraints_current(rdev, rdev->constraints);
1408 	if (ret != 0)
1409 		return ret;
1410 
1411 	if (rdev->constraints->ilim_uA && ops->set_input_current_limit) {
1412 		ret = ops->set_input_current_limit(rdev,
1413 						   rdev->constraints->ilim_uA);
1414 		if (ret < 0) {
1415 			rdev_err(rdev, "failed to set input limit: %pe\n", ERR_PTR(ret));
1416 			return ret;
1417 		}
1418 	}
1419 
1420 	/* do we need to setup our suspend state */
1421 	if (rdev->constraints->initial_state) {
1422 		ret = suspend_set_initial_state(rdev);
1423 		if (ret < 0) {
1424 			rdev_err(rdev, "failed to set suspend state: %pe\n", ERR_PTR(ret));
1425 			return ret;
1426 		}
1427 	}
1428 
1429 	if (rdev->constraints->initial_mode) {
1430 		if (!ops->set_mode) {
1431 			rdev_err(rdev, "no set_mode operation\n");
1432 			return -EINVAL;
1433 		}
1434 
1435 		ret = ops->set_mode(rdev, rdev->constraints->initial_mode);
1436 		if (ret < 0) {
1437 			rdev_err(rdev, "failed to set initial mode: %pe\n", ERR_PTR(ret));
1438 			return ret;
1439 		}
1440 	} else if (rdev->constraints->system_load) {
1441 		/*
1442 		 * We'll only apply the initial system load if an
1443 		 * initial mode wasn't specified.
1444 		 */
1445 		drms_uA_update(rdev);
1446 	}
1447 
1448 	if ((rdev->constraints->ramp_delay || rdev->constraints->ramp_disable)
1449 		&& ops->set_ramp_delay) {
1450 		ret = ops->set_ramp_delay(rdev, rdev->constraints->ramp_delay);
1451 		if (ret < 0) {
1452 			rdev_err(rdev, "failed to set ramp_delay: %pe\n", ERR_PTR(ret));
1453 			return ret;
1454 		}
1455 	}
1456 
1457 	if (rdev->constraints->pull_down && ops->set_pull_down) {
1458 		ret = ops->set_pull_down(rdev);
1459 		if (ret < 0) {
1460 			rdev_err(rdev, "failed to set pull down: %pe\n", ERR_PTR(ret));
1461 			return ret;
1462 		}
1463 	}
1464 
1465 	if (rdev->constraints->soft_start && ops->set_soft_start) {
1466 		ret = ops->set_soft_start(rdev);
1467 		if (ret < 0) {
1468 			rdev_err(rdev, "failed to set soft start: %pe\n", ERR_PTR(ret));
1469 			return ret;
1470 		}
1471 	}
1472 
1473 	/*
1474 	 * Existing logic does not warn if over_current_protection is given as
1475 	 * a constraint but driver does not support that. I think we should
1476 	 * warn about this type of issues as it is possible someone changes
1477 	 * PMIC on board to another type - and the another PMIC's driver does
1478 	 * not support setting protection. Board composer may happily believe
1479 	 * the DT limits are respected - especially if the new PMIC HW also
1480 	 * supports protection but the driver does not. I won't change the logic
1481 	 * without hearing more experienced opinion on this though.
1482 	 *
1483 	 * If warning is seen as a good idea then we can merge handling the
1484 	 * over-curret protection and detection and get rid of this special
1485 	 * handling.
1486 	 */
1487 	if (rdev->constraints->over_current_protection
1488 		&& ops->set_over_current_protection) {
1489 		int lim = rdev->constraints->over_curr_limits.prot;
1490 
1491 		ret = ops->set_over_current_protection(rdev, lim,
1492 						       REGULATOR_SEVERITY_PROT,
1493 						       true);
1494 		if (ret < 0) {
1495 			rdev_err(rdev, "failed to set over current protection: %pe\n",
1496 				 ERR_PTR(ret));
1497 			return ret;
1498 		}
1499 	}
1500 
1501 	if (rdev->constraints->over_current_detection)
1502 		ret = handle_notify_limits(rdev,
1503 					   ops->set_over_current_protection,
1504 					   &rdev->constraints->over_curr_limits);
1505 	if (ret) {
1506 		if (ret != -EOPNOTSUPP) {
1507 			rdev_err(rdev, "failed to set over current limits: %pe\n",
1508 				 ERR_PTR(ret));
1509 			return ret;
1510 		}
1511 		rdev_warn(rdev,
1512 			  "IC does not support requested over-current limits\n");
1513 	}
1514 
1515 	if (rdev->constraints->over_voltage_detection)
1516 		ret = handle_notify_limits(rdev,
1517 					   ops->set_over_voltage_protection,
1518 					   &rdev->constraints->over_voltage_limits);
1519 	if (ret) {
1520 		if (ret != -EOPNOTSUPP) {
1521 			rdev_err(rdev, "failed to set over voltage limits %pe\n",
1522 				 ERR_PTR(ret));
1523 			return ret;
1524 		}
1525 		rdev_warn(rdev,
1526 			  "IC does not support requested over voltage limits\n");
1527 	}
1528 
1529 	if (rdev->constraints->under_voltage_detection)
1530 		ret = handle_notify_limits(rdev,
1531 					   ops->set_under_voltage_protection,
1532 					   &rdev->constraints->under_voltage_limits);
1533 	if (ret) {
1534 		if (ret != -EOPNOTSUPP) {
1535 			rdev_err(rdev, "failed to set under voltage limits %pe\n",
1536 				 ERR_PTR(ret));
1537 			return ret;
1538 		}
1539 		rdev_warn(rdev,
1540 			  "IC does not support requested under voltage limits\n");
1541 	}
1542 
1543 	if (rdev->constraints->over_temp_detection)
1544 		ret = handle_notify_limits(rdev,
1545 					   ops->set_thermal_protection,
1546 					   &rdev->constraints->temp_limits);
1547 	if (ret) {
1548 		if (ret != -EOPNOTSUPP) {
1549 			rdev_err(rdev, "failed to set temperature limits %pe\n",
1550 				 ERR_PTR(ret));
1551 			return ret;
1552 		}
1553 		rdev_warn(rdev,
1554 			  "IC does not support requested temperature limits\n");
1555 	}
1556 
1557 	if (rdev->constraints->active_discharge && ops->set_active_discharge) {
1558 		bool ad_state = (rdev->constraints->active_discharge ==
1559 			      REGULATOR_ACTIVE_DISCHARGE_ENABLE) ? true : false;
1560 
1561 		ret = ops->set_active_discharge(rdev, ad_state);
1562 		if (ret < 0) {
1563 			rdev_err(rdev, "failed to set active discharge: %pe\n", ERR_PTR(ret));
1564 			return ret;
1565 		}
1566 	}
1567 
1568 	/*
1569 	 * If there is no mechanism for controlling the regulator then
1570 	 * flag it as always_on so we don't end up duplicating checks
1571 	 * for this so much.  Note that we could control the state of
1572 	 * a supply to control the output on a regulator that has no
1573 	 * direct control.
1574 	 */
1575 	if (!rdev->ena_pin && !ops->enable) {
1576 		if (rdev->supply_name && !rdev->supply)
1577 			return -EPROBE_DEFER;
1578 
1579 		if (rdev->supply)
1580 			rdev->constraints->always_on =
1581 				rdev->supply->rdev->constraints->always_on;
1582 		else
1583 			rdev->constraints->always_on = true;
1584 	}
1585 
1586 	if (rdev->desc->off_on_delay)
1587 		rdev->last_off = ktime_get_boottime();
1588 
1589 	/* If the constraints say the regulator should be on at this point
1590 	 * and we have control then make sure it is enabled.
1591 	 */
1592 	if (rdev->constraints->always_on || rdev->constraints->boot_on) {
1593 		/* If we want to enable this regulator, make sure that we know
1594 		 * the supplying regulator.
1595 		 */
1596 		if (rdev->supply_name && !rdev->supply)
1597 			return -EPROBE_DEFER;
1598 
1599 		/* If supplying regulator has already been enabled,
1600 		 * it's not intended to have use_count increment
1601 		 * when rdev is only boot-on.
1602 		 */
1603 		if (rdev->supply &&
1604 		    (rdev->constraints->always_on ||
1605 		     !regulator_is_enabled(rdev->supply))) {
1606 			ret = regulator_enable(rdev->supply);
1607 			if (ret < 0) {
1608 				_regulator_put(rdev->supply);
1609 				rdev->supply = NULL;
1610 				return ret;
1611 			}
1612 		}
1613 
1614 		ret = _regulator_do_enable(rdev);
1615 		if (ret < 0 && ret != -EINVAL) {
1616 			rdev_err(rdev, "failed to enable: %pe\n", ERR_PTR(ret));
1617 			return ret;
1618 		}
1619 
1620 		if (rdev->constraints->always_on)
1621 			rdev->use_count++;
1622 	}
1623 
1624 	print_constraints(rdev);
1625 	return 0;
1626 }
1627 
1628 /**
1629  * set_supply - set regulator supply regulator
1630  * @rdev: regulator name
1631  * @supply_rdev: supply regulator name
1632  *
1633  * Called by platform initialisation code to set the supply regulator for this
1634  * regulator. This ensures that a regulators supply will also be enabled by the
1635  * core if it's child is enabled.
1636  */
1637 static int set_supply(struct regulator_dev *rdev,
1638 		      struct regulator_dev *supply_rdev)
1639 {
1640 	int err;
1641 
1642 	rdev_dbg(rdev, "supplied by %s\n", rdev_get_name(supply_rdev));
1643 
1644 	if (!try_module_get(supply_rdev->owner))
1645 		return -ENODEV;
1646 
1647 	rdev->supply = create_regulator(supply_rdev, &rdev->dev, "SUPPLY");
1648 	if (rdev->supply == NULL) {
1649 		module_put(supply_rdev->owner);
1650 		err = -ENOMEM;
1651 		return err;
1652 	}
1653 	supply_rdev->open_count++;
1654 
1655 	return 0;
1656 }
1657 
1658 /**
1659  * set_consumer_device_supply - Bind a regulator to a symbolic supply
1660  * @rdev:         regulator source
1661  * @consumer_dev_name: dev_name() string for device supply applies to
1662  * @supply:       symbolic name for supply
1663  *
1664  * Allows platform initialisation code to map physical regulator
1665  * sources to symbolic names for supplies for use by devices.  Devices
1666  * should use these symbolic names to request regulators, avoiding the
1667  * need to provide board-specific regulator names as platform data.
1668  */
1669 static int set_consumer_device_supply(struct regulator_dev *rdev,
1670 				      const char *consumer_dev_name,
1671 				      const char *supply)
1672 {
1673 	struct regulator_map *node, *new_node;
1674 	int has_dev;
1675 
1676 	if (supply == NULL)
1677 		return -EINVAL;
1678 
1679 	if (consumer_dev_name != NULL)
1680 		has_dev = 1;
1681 	else
1682 		has_dev = 0;
1683 
1684 	new_node = kzalloc(sizeof(struct regulator_map), GFP_KERNEL);
1685 	if (new_node == NULL)
1686 		return -ENOMEM;
1687 
1688 	new_node->regulator = rdev;
1689 	new_node->supply = supply;
1690 
1691 	if (has_dev) {
1692 		new_node->dev_name = kstrdup(consumer_dev_name, GFP_KERNEL);
1693 		if (new_node->dev_name == NULL) {
1694 			kfree(new_node);
1695 			return -ENOMEM;
1696 		}
1697 	}
1698 
1699 	mutex_lock(&regulator_list_mutex);
1700 	list_for_each_entry(node, &regulator_map_list, list) {
1701 		if (node->dev_name && consumer_dev_name) {
1702 			if (strcmp(node->dev_name, consumer_dev_name) != 0)
1703 				continue;
1704 		} else if (node->dev_name || consumer_dev_name) {
1705 			continue;
1706 		}
1707 
1708 		if (strcmp(node->supply, supply) != 0)
1709 			continue;
1710 
1711 		pr_debug("%s: %s/%s is '%s' supply; fail %s/%s\n",
1712 			 consumer_dev_name,
1713 			 dev_name(&node->regulator->dev),
1714 			 node->regulator->desc->name,
1715 			 supply,
1716 			 dev_name(&rdev->dev), rdev_get_name(rdev));
1717 		goto fail;
1718 	}
1719 
1720 	list_add(&new_node->list, &regulator_map_list);
1721 	mutex_unlock(&regulator_list_mutex);
1722 
1723 	return 0;
1724 
1725 fail:
1726 	mutex_unlock(&regulator_list_mutex);
1727 	kfree(new_node->dev_name);
1728 	kfree(new_node);
1729 	return -EBUSY;
1730 }
1731 
1732 static void unset_regulator_supplies(struct regulator_dev *rdev)
1733 {
1734 	struct regulator_map *node, *n;
1735 
1736 	list_for_each_entry_safe(node, n, &regulator_map_list, list) {
1737 		if (rdev == node->regulator) {
1738 			list_del(&node->list);
1739 			kfree(node->dev_name);
1740 			kfree(node);
1741 		}
1742 	}
1743 }
1744 
1745 #ifdef CONFIG_DEBUG_FS
1746 static ssize_t constraint_flags_read_file(struct file *file,
1747 					  char __user *user_buf,
1748 					  size_t count, loff_t *ppos)
1749 {
1750 	const struct regulator *regulator = file->private_data;
1751 	const struct regulation_constraints *c = regulator->rdev->constraints;
1752 	char *buf;
1753 	ssize_t ret;
1754 
1755 	if (!c)
1756 		return 0;
1757 
1758 	buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
1759 	if (!buf)
1760 		return -ENOMEM;
1761 
1762 	ret = snprintf(buf, PAGE_SIZE,
1763 			"always_on: %u\n"
1764 			"boot_on: %u\n"
1765 			"apply_uV: %u\n"
1766 			"ramp_disable: %u\n"
1767 			"soft_start: %u\n"
1768 			"pull_down: %u\n"
1769 			"over_current_protection: %u\n",
1770 			c->always_on,
1771 			c->boot_on,
1772 			c->apply_uV,
1773 			c->ramp_disable,
1774 			c->soft_start,
1775 			c->pull_down,
1776 			c->over_current_protection);
1777 
1778 	ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
1779 	kfree(buf);
1780 
1781 	return ret;
1782 }
1783 
1784 #endif
1785 
1786 static const struct file_operations constraint_flags_fops = {
1787 #ifdef CONFIG_DEBUG_FS
1788 	.open = simple_open,
1789 	.read = constraint_flags_read_file,
1790 	.llseek = default_llseek,
1791 #endif
1792 };
1793 
1794 #define REG_STR_SIZE	64
1795 
1796 static struct regulator *create_regulator(struct regulator_dev *rdev,
1797 					  struct device *dev,
1798 					  const char *supply_name)
1799 {
1800 	struct regulator *regulator;
1801 	int err = 0;
1802 
1803 	if (dev) {
1804 		char buf[REG_STR_SIZE];
1805 		int size;
1806 
1807 		size = snprintf(buf, REG_STR_SIZE, "%s-%s",
1808 				dev->kobj.name, supply_name);
1809 		if (size >= REG_STR_SIZE)
1810 			return NULL;
1811 
1812 		supply_name = kstrdup(buf, GFP_KERNEL);
1813 		if (supply_name == NULL)
1814 			return NULL;
1815 	} else {
1816 		supply_name = kstrdup_const(supply_name, GFP_KERNEL);
1817 		if (supply_name == NULL)
1818 			return NULL;
1819 	}
1820 
1821 	regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
1822 	if (regulator == NULL) {
1823 		kfree_const(supply_name);
1824 		return NULL;
1825 	}
1826 
1827 	regulator->rdev = rdev;
1828 	regulator->supply_name = supply_name;
1829 
1830 	regulator_lock(rdev);
1831 	list_add(&regulator->list, &rdev->consumer_list);
1832 	regulator_unlock(rdev);
1833 
1834 	if (dev) {
1835 		regulator->dev = dev;
1836 
1837 		/* Add a link to the device sysfs entry */
1838 		err = sysfs_create_link_nowarn(&rdev->dev.kobj, &dev->kobj,
1839 					       supply_name);
1840 		if (err) {
1841 			rdev_dbg(rdev, "could not add device link %s: %pe\n",
1842 				  dev->kobj.name, ERR_PTR(err));
1843 			/* non-fatal */
1844 		}
1845 	}
1846 
1847 	if (err != -EEXIST)
1848 		regulator->debugfs = debugfs_create_dir(supply_name, rdev->debugfs);
1849 	if (!regulator->debugfs) {
1850 		rdev_dbg(rdev, "Failed to create debugfs directory\n");
1851 	} else {
1852 		debugfs_create_u32("uA_load", 0444, regulator->debugfs,
1853 				   &regulator->uA_load);
1854 		debugfs_create_u32("min_uV", 0444, regulator->debugfs,
1855 				   &regulator->voltage[PM_SUSPEND_ON].min_uV);
1856 		debugfs_create_u32("max_uV", 0444, regulator->debugfs,
1857 				   &regulator->voltage[PM_SUSPEND_ON].max_uV);
1858 		debugfs_create_file("constraint_flags", 0444,
1859 				    regulator->debugfs, regulator,
1860 				    &constraint_flags_fops);
1861 	}
1862 
1863 	/*
1864 	 * Check now if the regulator is an always on regulator - if
1865 	 * it is then we don't need to do nearly so much work for
1866 	 * enable/disable calls.
1867 	 */
1868 	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_STATUS) &&
1869 	    _regulator_is_enabled(rdev))
1870 		regulator->always_on = true;
1871 
1872 	return regulator;
1873 }
1874 
1875 static int _regulator_get_enable_time(struct regulator_dev *rdev)
1876 {
1877 	if (rdev->constraints && rdev->constraints->enable_time)
1878 		return rdev->constraints->enable_time;
1879 	if (rdev->desc->ops->enable_time)
1880 		return rdev->desc->ops->enable_time(rdev);
1881 	return rdev->desc->enable_time;
1882 }
1883 
1884 static struct regulator_supply_alias *regulator_find_supply_alias(
1885 		struct device *dev, const char *supply)
1886 {
1887 	struct regulator_supply_alias *map;
1888 
1889 	list_for_each_entry(map, &regulator_supply_alias_list, list)
1890 		if (map->src_dev == dev && strcmp(map->src_supply, supply) == 0)
1891 			return map;
1892 
1893 	return NULL;
1894 }
1895 
1896 static void regulator_supply_alias(struct device **dev, const char **supply)
1897 {
1898 	struct regulator_supply_alias *map;
1899 
1900 	map = regulator_find_supply_alias(*dev, *supply);
1901 	if (map) {
1902 		dev_dbg(*dev, "Mapping supply %s to %s,%s\n",
1903 				*supply, map->alias_supply,
1904 				dev_name(map->alias_dev));
1905 		*dev = map->alias_dev;
1906 		*supply = map->alias_supply;
1907 	}
1908 }
1909 
1910 static int regulator_match(struct device *dev, const void *data)
1911 {
1912 	struct regulator_dev *r = dev_to_rdev(dev);
1913 
1914 	return strcmp(rdev_get_name(r), data) == 0;
1915 }
1916 
1917 static struct regulator_dev *regulator_lookup_by_name(const char *name)
1918 {
1919 	struct device *dev;
1920 
1921 	dev = class_find_device(&regulator_class, NULL, name, regulator_match);
1922 
1923 	return dev ? dev_to_rdev(dev) : NULL;
1924 }
1925 
1926 /**
1927  * regulator_dev_lookup - lookup a regulator device.
1928  * @dev: device for regulator "consumer".
1929  * @supply: Supply name or regulator ID.
1930  *
1931  * If successful, returns a struct regulator_dev that corresponds to the name
1932  * @supply and with the embedded struct device refcount incremented by one.
1933  * The refcount must be dropped by calling put_device().
1934  * On failure one of the following ERR-PTR-encoded values is returned:
1935  * -ENODEV if lookup fails permanently, -EPROBE_DEFER if lookup could succeed
1936  * in the future.
1937  */
1938 static struct regulator_dev *regulator_dev_lookup(struct device *dev,
1939 						  const char *supply)
1940 {
1941 	struct regulator_dev *r = NULL;
1942 	struct device_node *node;
1943 	struct regulator_map *map;
1944 	const char *devname = NULL;
1945 
1946 	regulator_supply_alias(&dev, &supply);
1947 
1948 	/* first do a dt based lookup */
1949 	if (dev && dev->of_node) {
1950 		node = of_get_regulator(dev, supply);
1951 		if (node) {
1952 			r = of_find_regulator_by_node(node);
1953 			of_node_put(node);
1954 			if (r)
1955 				return r;
1956 
1957 			/*
1958 			 * We have a node, but there is no device.
1959 			 * assume it has not registered yet.
1960 			 */
1961 			return ERR_PTR(-EPROBE_DEFER);
1962 		}
1963 	}
1964 
1965 	/* if not found, try doing it non-dt way */
1966 	if (dev)
1967 		devname = dev_name(dev);
1968 
1969 	mutex_lock(&regulator_list_mutex);
1970 	list_for_each_entry(map, &regulator_map_list, list) {
1971 		/* If the mapping has a device set up it must match */
1972 		if (map->dev_name &&
1973 		    (!devname || strcmp(map->dev_name, devname)))
1974 			continue;
1975 
1976 		if (strcmp(map->supply, supply) == 0 &&
1977 		    get_device(&map->regulator->dev)) {
1978 			r = map->regulator;
1979 			break;
1980 		}
1981 	}
1982 	mutex_unlock(&regulator_list_mutex);
1983 
1984 	if (r)
1985 		return r;
1986 
1987 	r = regulator_lookup_by_name(supply);
1988 	if (r)
1989 		return r;
1990 
1991 	return ERR_PTR(-ENODEV);
1992 }
1993 
1994 static int regulator_resolve_supply(struct regulator_dev *rdev)
1995 {
1996 	struct regulator_dev *r;
1997 	struct device *dev = rdev->dev.parent;
1998 	int ret = 0;
1999 
2000 	/* No supply to resolve? */
2001 	if (!rdev->supply_name)
2002 		return 0;
2003 
2004 	/* Supply already resolved? (fast-path without locking contention) */
2005 	if (rdev->supply)
2006 		return 0;
2007 
2008 	r = regulator_dev_lookup(dev, rdev->supply_name);
2009 	if (IS_ERR(r)) {
2010 		ret = PTR_ERR(r);
2011 
2012 		/* Did the lookup explicitly defer for us? */
2013 		if (ret == -EPROBE_DEFER)
2014 			goto out;
2015 
2016 		if (have_full_constraints()) {
2017 			r = dummy_regulator_rdev;
2018 			get_device(&r->dev);
2019 		} else {
2020 			dev_err(dev, "Failed to resolve %s-supply for %s\n",
2021 				rdev->supply_name, rdev->desc->name);
2022 			ret = -EPROBE_DEFER;
2023 			goto out;
2024 		}
2025 	}
2026 
2027 	if (r == rdev) {
2028 		dev_err(dev, "Supply for %s (%s) resolved to itself\n",
2029 			rdev->desc->name, rdev->supply_name);
2030 		if (!have_full_constraints()) {
2031 			ret = -EINVAL;
2032 			goto out;
2033 		}
2034 		r = dummy_regulator_rdev;
2035 		get_device(&r->dev);
2036 	}
2037 
2038 	/*
2039 	 * If the supply's parent device is not the same as the
2040 	 * regulator's parent device, then ensure the parent device
2041 	 * is bound before we resolve the supply, in case the parent
2042 	 * device get probe deferred and unregisters the supply.
2043 	 */
2044 	if (r->dev.parent && r->dev.parent != rdev->dev.parent) {
2045 		if (!device_is_bound(r->dev.parent)) {
2046 			put_device(&r->dev);
2047 			ret = -EPROBE_DEFER;
2048 			goto out;
2049 		}
2050 	}
2051 
2052 	/* Recursively resolve the supply of the supply */
2053 	ret = regulator_resolve_supply(r);
2054 	if (ret < 0) {
2055 		put_device(&r->dev);
2056 		goto out;
2057 	}
2058 
2059 	/*
2060 	 * Recheck rdev->supply with rdev->mutex lock held to avoid a race
2061 	 * between rdev->supply null check and setting rdev->supply in
2062 	 * set_supply() from concurrent tasks.
2063 	 */
2064 	regulator_lock(rdev);
2065 
2066 	/* Supply just resolved by a concurrent task? */
2067 	if (rdev->supply) {
2068 		regulator_unlock(rdev);
2069 		put_device(&r->dev);
2070 		goto out;
2071 	}
2072 
2073 	ret = set_supply(rdev, r);
2074 	if (ret < 0) {
2075 		regulator_unlock(rdev);
2076 		put_device(&r->dev);
2077 		goto out;
2078 	}
2079 
2080 	regulator_unlock(rdev);
2081 
2082 	/*
2083 	 * In set_machine_constraints() we may have turned this regulator on
2084 	 * but we couldn't propagate to the supply if it hadn't been resolved
2085 	 * yet.  Do it now.
2086 	 */
2087 	if (rdev->use_count) {
2088 		ret = regulator_enable(rdev->supply);
2089 		if (ret < 0) {
2090 			_regulator_put(rdev->supply);
2091 			rdev->supply = NULL;
2092 			goto out;
2093 		}
2094 	}
2095 
2096 out:
2097 	return ret;
2098 }
2099 
2100 /* Internal regulator request function */
2101 struct regulator *_regulator_get(struct device *dev, const char *id,
2102 				 enum regulator_get_type get_type)
2103 {
2104 	struct regulator_dev *rdev;
2105 	struct regulator *regulator;
2106 	struct device_link *link;
2107 	int ret;
2108 
2109 	if (get_type >= MAX_GET_TYPE) {
2110 		dev_err(dev, "invalid type %d in %s\n", get_type, __func__);
2111 		return ERR_PTR(-EINVAL);
2112 	}
2113 
2114 	if (id == NULL) {
2115 		pr_err("get() with no identifier\n");
2116 		return ERR_PTR(-EINVAL);
2117 	}
2118 
2119 	rdev = regulator_dev_lookup(dev, id);
2120 	if (IS_ERR(rdev)) {
2121 		ret = PTR_ERR(rdev);
2122 
2123 		/*
2124 		 * If regulator_dev_lookup() fails with error other
2125 		 * than -ENODEV our job here is done, we simply return it.
2126 		 */
2127 		if (ret != -ENODEV)
2128 			return ERR_PTR(ret);
2129 
2130 		if (!have_full_constraints()) {
2131 			dev_warn(dev,
2132 				 "incomplete constraints, dummy supplies not allowed\n");
2133 			return ERR_PTR(-ENODEV);
2134 		}
2135 
2136 		switch (get_type) {
2137 		case NORMAL_GET:
2138 			/*
2139 			 * Assume that a regulator is physically present and
2140 			 * enabled, even if it isn't hooked up, and just
2141 			 * provide a dummy.
2142 			 */
2143 			dev_warn(dev, "supply %s not found, using dummy regulator\n", id);
2144 			rdev = dummy_regulator_rdev;
2145 			get_device(&rdev->dev);
2146 			break;
2147 
2148 		case EXCLUSIVE_GET:
2149 			dev_warn(dev,
2150 				 "dummy supplies not allowed for exclusive requests\n");
2151 			fallthrough;
2152 
2153 		default:
2154 			return ERR_PTR(-ENODEV);
2155 		}
2156 	}
2157 
2158 	if (rdev->exclusive) {
2159 		regulator = ERR_PTR(-EPERM);
2160 		put_device(&rdev->dev);
2161 		return regulator;
2162 	}
2163 
2164 	if (get_type == EXCLUSIVE_GET && rdev->open_count) {
2165 		regulator = ERR_PTR(-EBUSY);
2166 		put_device(&rdev->dev);
2167 		return regulator;
2168 	}
2169 
2170 	mutex_lock(&regulator_list_mutex);
2171 	ret = (rdev->coupling_desc.n_resolved != rdev->coupling_desc.n_coupled);
2172 	mutex_unlock(&regulator_list_mutex);
2173 
2174 	if (ret != 0) {
2175 		regulator = ERR_PTR(-EPROBE_DEFER);
2176 		put_device(&rdev->dev);
2177 		return regulator;
2178 	}
2179 
2180 	ret = regulator_resolve_supply(rdev);
2181 	if (ret < 0) {
2182 		regulator = ERR_PTR(ret);
2183 		put_device(&rdev->dev);
2184 		return regulator;
2185 	}
2186 
2187 	if (!try_module_get(rdev->owner)) {
2188 		regulator = ERR_PTR(-EPROBE_DEFER);
2189 		put_device(&rdev->dev);
2190 		return regulator;
2191 	}
2192 
2193 	regulator = create_regulator(rdev, dev, id);
2194 	if (regulator == NULL) {
2195 		regulator = ERR_PTR(-ENOMEM);
2196 		module_put(rdev->owner);
2197 		put_device(&rdev->dev);
2198 		return regulator;
2199 	}
2200 
2201 	rdev->open_count++;
2202 	if (get_type == EXCLUSIVE_GET) {
2203 		rdev->exclusive = 1;
2204 
2205 		ret = _regulator_is_enabled(rdev);
2206 		if (ret > 0) {
2207 			rdev->use_count = 1;
2208 			regulator->enable_count = 1;
2209 		} else {
2210 			rdev->use_count = 0;
2211 			regulator->enable_count = 0;
2212 		}
2213 	}
2214 
2215 	link = device_link_add(dev, &rdev->dev, DL_FLAG_STATELESS);
2216 	if (!IS_ERR_OR_NULL(link))
2217 		regulator->device_link = true;
2218 
2219 	return regulator;
2220 }
2221 
2222 /**
2223  * regulator_get - lookup and obtain a reference to a regulator.
2224  * @dev: device for regulator "consumer"
2225  * @id: Supply name or regulator ID.
2226  *
2227  * Returns a struct regulator corresponding to the regulator producer,
2228  * or IS_ERR() condition containing errno.
2229  *
2230  * Use of supply names configured via set_consumer_device_supply() is
2231  * strongly encouraged.  It is recommended that the supply name used
2232  * should match the name used for the supply and/or the relevant
2233  * device pins in the datasheet.
2234  */
2235 struct regulator *regulator_get(struct device *dev, const char *id)
2236 {
2237 	return _regulator_get(dev, id, NORMAL_GET);
2238 }
2239 EXPORT_SYMBOL_GPL(regulator_get);
2240 
2241 /**
2242  * regulator_get_exclusive - obtain exclusive access to a regulator.
2243  * @dev: device for regulator "consumer"
2244  * @id: Supply name or regulator ID.
2245  *
2246  * Returns a struct regulator corresponding to the regulator producer,
2247  * or IS_ERR() condition containing errno.  Other consumers will be
2248  * unable to obtain this regulator while this reference is held and the
2249  * use count for the regulator will be initialised to reflect the current
2250  * state of the regulator.
2251  *
2252  * This is intended for use by consumers which cannot tolerate shared
2253  * use of the regulator such as those which need to force the
2254  * regulator off for correct operation of the hardware they are
2255  * controlling.
2256  *
2257  * Use of supply names configured via set_consumer_device_supply() is
2258  * strongly encouraged.  It is recommended that the supply name used
2259  * should match the name used for the supply and/or the relevant
2260  * device pins in the datasheet.
2261  */
2262 struct regulator *regulator_get_exclusive(struct device *dev, const char *id)
2263 {
2264 	return _regulator_get(dev, id, EXCLUSIVE_GET);
2265 }
2266 EXPORT_SYMBOL_GPL(regulator_get_exclusive);
2267 
2268 /**
2269  * regulator_get_optional - obtain optional access to a regulator.
2270  * @dev: device for regulator "consumer"
2271  * @id: Supply name or regulator ID.
2272  *
2273  * Returns a struct regulator corresponding to the regulator producer,
2274  * or IS_ERR() condition containing errno.
2275  *
2276  * This is intended for use by consumers for devices which can have
2277  * some supplies unconnected in normal use, such as some MMC devices.
2278  * It can allow the regulator core to provide stub supplies for other
2279  * supplies requested using normal regulator_get() calls without
2280  * disrupting the operation of drivers that can handle absent
2281  * supplies.
2282  *
2283  * Use of supply names configured via set_consumer_device_supply() is
2284  * strongly encouraged.  It is recommended that the supply name used
2285  * should match the name used for the supply and/or the relevant
2286  * device pins in the datasheet.
2287  */
2288 struct regulator *regulator_get_optional(struct device *dev, const char *id)
2289 {
2290 	return _regulator_get(dev, id, OPTIONAL_GET);
2291 }
2292 EXPORT_SYMBOL_GPL(regulator_get_optional);
2293 
2294 static void destroy_regulator(struct regulator *regulator)
2295 {
2296 	struct regulator_dev *rdev = regulator->rdev;
2297 
2298 	debugfs_remove_recursive(regulator->debugfs);
2299 
2300 	if (regulator->dev) {
2301 		if (regulator->device_link)
2302 			device_link_remove(regulator->dev, &rdev->dev);
2303 
2304 		/* remove any sysfs entries */
2305 		sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
2306 	}
2307 
2308 	regulator_lock(rdev);
2309 	list_del(&regulator->list);
2310 
2311 	rdev->open_count--;
2312 	rdev->exclusive = 0;
2313 	regulator_unlock(rdev);
2314 
2315 	kfree_const(regulator->supply_name);
2316 	kfree(regulator);
2317 }
2318 
2319 /* regulator_list_mutex lock held by regulator_put() */
2320 static void _regulator_put(struct regulator *regulator)
2321 {
2322 	struct regulator_dev *rdev;
2323 
2324 	if (IS_ERR_OR_NULL(regulator))
2325 		return;
2326 
2327 	lockdep_assert_held_once(&regulator_list_mutex);
2328 
2329 	/* Docs say you must disable before calling regulator_put() */
2330 	WARN_ON(regulator->enable_count);
2331 
2332 	rdev = regulator->rdev;
2333 
2334 	destroy_regulator(regulator);
2335 
2336 	module_put(rdev->owner);
2337 	put_device(&rdev->dev);
2338 }
2339 
2340 /**
2341  * regulator_put - "free" the regulator source
2342  * @regulator: regulator source
2343  *
2344  * Note: drivers must ensure that all regulator_enable calls made on this
2345  * regulator source are balanced by regulator_disable calls prior to calling
2346  * this function.
2347  */
2348 void regulator_put(struct regulator *regulator)
2349 {
2350 	mutex_lock(&regulator_list_mutex);
2351 	_regulator_put(regulator);
2352 	mutex_unlock(&regulator_list_mutex);
2353 }
2354 EXPORT_SYMBOL_GPL(regulator_put);
2355 
2356 /**
2357  * regulator_register_supply_alias - Provide device alias for supply lookup
2358  *
2359  * @dev: device that will be given as the regulator "consumer"
2360  * @id: Supply name or regulator ID
2361  * @alias_dev: device that should be used to lookup the supply
2362  * @alias_id: Supply name or regulator ID that should be used to lookup the
2363  * supply
2364  *
2365  * All lookups for id on dev will instead be conducted for alias_id on
2366  * alias_dev.
2367  */
2368 int regulator_register_supply_alias(struct device *dev, const char *id,
2369 				    struct device *alias_dev,
2370 				    const char *alias_id)
2371 {
2372 	struct regulator_supply_alias *map;
2373 
2374 	map = regulator_find_supply_alias(dev, id);
2375 	if (map)
2376 		return -EEXIST;
2377 
2378 	map = kzalloc(sizeof(struct regulator_supply_alias), GFP_KERNEL);
2379 	if (!map)
2380 		return -ENOMEM;
2381 
2382 	map->src_dev = dev;
2383 	map->src_supply = id;
2384 	map->alias_dev = alias_dev;
2385 	map->alias_supply = alias_id;
2386 
2387 	list_add(&map->list, &regulator_supply_alias_list);
2388 
2389 	pr_info("Adding alias for supply %s,%s -> %s,%s\n",
2390 		id, dev_name(dev), alias_id, dev_name(alias_dev));
2391 
2392 	return 0;
2393 }
2394 EXPORT_SYMBOL_GPL(regulator_register_supply_alias);
2395 
2396 /**
2397  * regulator_unregister_supply_alias - Remove device alias
2398  *
2399  * @dev: device that will be given as the regulator "consumer"
2400  * @id: Supply name or regulator ID
2401  *
2402  * Remove a lookup alias if one exists for id on dev.
2403  */
2404 void regulator_unregister_supply_alias(struct device *dev, const char *id)
2405 {
2406 	struct regulator_supply_alias *map;
2407 
2408 	map = regulator_find_supply_alias(dev, id);
2409 	if (map) {
2410 		list_del(&map->list);
2411 		kfree(map);
2412 	}
2413 }
2414 EXPORT_SYMBOL_GPL(regulator_unregister_supply_alias);
2415 
2416 /**
2417  * regulator_bulk_register_supply_alias - register multiple aliases
2418  *
2419  * @dev: device that will be given as the regulator "consumer"
2420  * @id: List of supply names or regulator IDs
2421  * @alias_dev: device that should be used to lookup the supply
2422  * @alias_id: List of supply names or regulator IDs that should be used to
2423  * lookup the supply
2424  * @num_id: Number of aliases to register
2425  *
2426  * @return 0 on success, an errno on failure.
2427  *
2428  * This helper function allows drivers to register several supply
2429  * aliases in one operation.  If any of the aliases cannot be
2430  * registered any aliases that were registered will be removed
2431  * before returning to the caller.
2432  */
2433 int regulator_bulk_register_supply_alias(struct device *dev,
2434 					 const char *const *id,
2435 					 struct device *alias_dev,
2436 					 const char *const *alias_id,
2437 					 int num_id)
2438 {
2439 	int i;
2440 	int ret;
2441 
2442 	for (i = 0; i < num_id; ++i) {
2443 		ret = regulator_register_supply_alias(dev, id[i], alias_dev,
2444 						      alias_id[i]);
2445 		if (ret < 0)
2446 			goto err;
2447 	}
2448 
2449 	return 0;
2450 
2451 err:
2452 	dev_err(dev,
2453 		"Failed to create supply alias %s,%s -> %s,%s\n",
2454 		id[i], dev_name(dev), alias_id[i], dev_name(alias_dev));
2455 
2456 	while (--i >= 0)
2457 		regulator_unregister_supply_alias(dev, id[i]);
2458 
2459 	return ret;
2460 }
2461 EXPORT_SYMBOL_GPL(regulator_bulk_register_supply_alias);
2462 
2463 /**
2464  * regulator_bulk_unregister_supply_alias - unregister multiple aliases
2465  *
2466  * @dev: device that will be given as the regulator "consumer"
2467  * @id: List of supply names or regulator IDs
2468  * @num_id: Number of aliases to unregister
2469  *
2470  * This helper function allows drivers to unregister several supply
2471  * aliases in one operation.
2472  */
2473 void regulator_bulk_unregister_supply_alias(struct device *dev,
2474 					    const char *const *id,
2475 					    int num_id)
2476 {
2477 	int i;
2478 
2479 	for (i = 0; i < num_id; ++i)
2480 		regulator_unregister_supply_alias(dev, id[i]);
2481 }
2482 EXPORT_SYMBOL_GPL(regulator_bulk_unregister_supply_alias);
2483 
2484 
2485 /* Manage enable GPIO list. Same GPIO pin can be shared among regulators */
2486 static int regulator_ena_gpio_request(struct regulator_dev *rdev,
2487 				const struct regulator_config *config)
2488 {
2489 	struct regulator_enable_gpio *pin, *new_pin;
2490 	struct gpio_desc *gpiod;
2491 
2492 	gpiod = config->ena_gpiod;
2493 	new_pin = kzalloc(sizeof(*new_pin), GFP_KERNEL);
2494 
2495 	mutex_lock(&regulator_list_mutex);
2496 
2497 	list_for_each_entry(pin, &regulator_ena_gpio_list, list) {
2498 		if (pin->gpiod == gpiod) {
2499 			rdev_dbg(rdev, "GPIO is already used\n");
2500 			goto update_ena_gpio_to_rdev;
2501 		}
2502 	}
2503 
2504 	if (new_pin == NULL) {
2505 		mutex_unlock(&regulator_list_mutex);
2506 		return -ENOMEM;
2507 	}
2508 
2509 	pin = new_pin;
2510 	new_pin = NULL;
2511 
2512 	pin->gpiod = gpiod;
2513 	list_add(&pin->list, &regulator_ena_gpio_list);
2514 
2515 update_ena_gpio_to_rdev:
2516 	pin->request_count++;
2517 	rdev->ena_pin = pin;
2518 
2519 	mutex_unlock(&regulator_list_mutex);
2520 	kfree(new_pin);
2521 
2522 	return 0;
2523 }
2524 
2525 static void regulator_ena_gpio_free(struct regulator_dev *rdev)
2526 {
2527 	struct regulator_enable_gpio *pin, *n;
2528 
2529 	if (!rdev->ena_pin)
2530 		return;
2531 
2532 	/* Free the GPIO only in case of no use */
2533 	list_for_each_entry_safe(pin, n, &regulator_ena_gpio_list, list) {
2534 		if (pin != rdev->ena_pin)
2535 			continue;
2536 
2537 		if (--pin->request_count)
2538 			break;
2539 
2540 		gpiod_put(pin->gpiod);
2541 		list_del(&pin->list);
2542 		kfree(pin);
2543 		break;
2544 	}
2545 
2546 	rdev->ena_pin = NULL;
2547 }
2548 
2549 /**
2550  * regulator_ena_gpio_ctrl - balance enable_count of each GPIO and actual GPIO pin control
2551  * @rdev: regulator_dev structure
2552  * @enable: enable GPIO at initial use?
2553  *
2554  * GPIO is enabled in case of initial use. (enable_count is 0)
2555  * GPIO is disabled when it is not shared any more. (enable_count <= 1)
2556  */
2557 static int regulator_ena_gpio_ctrl(struct regulator_dev *rdev, bool enable)
2558 {
2559 	struct regulator_enable_gpio *pin = rdev->ena_pin;
2560 
2561 	if (!pin)
2562 		return -EINVAL;
2563 
2564 	if (enable) {
2565 		/* Enable GPIO at initial use */
2566 		if (pin->enable_count == 0)
2567 			gpiod_set_value_cansleep(pin->gpiod, 1);
2568 
2569 		pin->enable_count++;
2570 	} else {
2571 		if (pin->enable_count > 1) {
2572 			pin->enable_count--;
2573 			return 0;
2574 		}
2575 
2576 		/* Disable GPIO if not used */
2577 		if (pin->enable_count <= 1) {
2578 			gpiod_set_value_cansleep(pin->gpiod, 0);
2579 			pin->enable_count = 0;
2580 		}
2581 	}
2582 
2583 	return 0;
2584 }
2585 
2586 /**
2587  * _regulator_delay_helper - a delay helper function
2588  * @delay: time to delay in microseconds
2589  *
2590  * Delay for the requested amount of time as per the guidelines in:
2591  *
2592  *     Documentation/timers/timers-howto.rst
2593  *
2594  * The assumption here is that these regulator operations will never used in
2595  * atomic context and therefore sleeping functions can be used.
2596  */
2597 static void _regulator_delay_helper(unsigned int delay)
2598 {
2599 	unsigned int ms = delay / 1000;
2600 	unsigned int us = delay % 1000;
2601 
2602 	if (ms > 0) {
2603 		/*
2604 		 * For small enough values, handle super-millisecond
2605 		 * delays in the usleep_range() call below.
2606 		 */
2607 		if (ms < 20)
2608 			us += ms * 1000;
2609 		else
2610 			msleep(ms);
2611 	}
2612 
2613 	/*
2614 	 * Give the scheduler some room to coalesce with any other
2615 	 * wakeup sources. For delays shorter than 10 us, don't even
2616 	 * bother setting up high-resolution timers and just busy-
2617 	 * loop.
2618 	 */
2619 	if (us >= 10)
2620 		usleep_range(us, us + 100);
2621 	else
2622 		udelay(us);
2623 }
2624 
2625 /**
2626  * _regulator_check_status_enabled
2627  *
2628  * A helper function to check if the regulator status can be interpreted
2629  * as 'regulator is enabled'.
2630  * @rdev: the regulator device to check
2631  *
2632  * Return:
2633  * * 1			- if status shows regulator is in enabled state
2634  * * 0			- if not enabled state
2635  * * Error Value	- as received from ops->get_status()
2636  */
2637 static inline int _regulator_check_status_enabled(struct regulator_dev *rdev)
2638 {
2639 	int ret = rdev->desc->ops->get_status(rdev);
2640 
2641 	if (ret < 0) {
2642 		rdev_info(rdev, "get_status returned error: %d\n", ret);
2643 		return ret;
2644 	}
2645 
2646 	switch (ret) {
2647 	case REGULATOR_STATUS_OFF:
2648 	case REGULATOR_STATUS_ERROR:
2649 	case REGULATOR_STATUS_UNDEFINED:
2650 		return 0;
2651 	default:
2652 		return 1;
2653 	}
2654 }
2655 
2656 static int _regulator_do_enable(struct regulator_dev *rdev)
2657 {
2658 	int ret, delay;
2659 
2660 	/* Query before enabling in case configuration dependent.  */
2661 	ret = _regulator_get_enable_time(rdev);
2662 	if (ret >= 0) {
2663 		delay = ret;
2664 	} else {
2665 		rdev_warn(rdev, "enable_time() failed: %pe\n", ERR_PTR(ret));
2666 		delay = 0;
2667 	}
2668 
2669 	trace_regulator_enable(rdev_get_name(rdev));
2670 
2671 	if (rdev->desc->off_on_delay && rdev->last_off) {
2672 		/* if needed, keep a distance of off_on_delay from last time
2673 		 * this regulator was disabled.
2674 		 */
2675 		ktime_t end = ktime_add_us(rdev->last_off, rdev->desc->off_on_delay);
2676 		s64 remaining = ktime_us_delta(end, ktime_get_boottime());
2677 
2678 		if (remaining > 0)
2679 			_regulator_delay_helper(remaining);
2680 	}
2681 
2682 	if (rdev->ena_pin) {
2683 		if (!rdev->ena_gpio_state) {
2684 			ret = regulator_ena_gpio_ctrl(rdev, true);
2685 			if (ret < 0)
2686 				return ret;
2687 			rdev->ena_gpio_state = 1;
2688 		}
2689 	} else if (rdev->desc->ops->enable) {
2690 		ret = rdev->desc->ops->enable(rdev);
2691 		if (ret < 0)
2692 			return ret;
2693 	} else {
2694 		return -EINVAL;
2695 	}
2696 
2697 	/* Allow the regulator to ramp; it would be useful to extend
2698 	 * this for bulk operations so that the regulators can ramp
2699 	 * together.
2700 	 */
2701 	trace_regulator_enable_delay(rdev_get_name(rdev));
2702 
2703 	/* If poll_enabled_time is set, poll upto the delay calculated
2704 	 * above, delaying poll_enabled_time uS to check if the regulator
2705 	 * actually got enabled.
2706 	 * If the regulator isn't enabled after our delay helper has expired,
2707 	 * return -ETIMEDOUT.
2708 	 */
2709 	if (rdev->desc->poll_enabled_time) {
2710 		int time_remaining = delay;
2711 
2712 		while (time_remaining > 0) {
2713 			_regulator_delay_helper(rdev->desc->poll_enabled_time);
2714 
2715 			if (rdev->desc->ops->get_status) {
2716 				ret = _regulator_check_status_enabled(rdev);
2717 				if (ret < 0)
2718 					return ret;
2719 				else if (ret)
2720 					break;
2721 			} else if (rdev->desc->ops->is_enabled(rdev))
2722 				break;
2723 
2724 			time_remaining -= rdev->desc->poll_enabled_time;
2725 		}
2726 
2727 		if (time_remaining <= 0) {
2728 			rdev_err(rdev, "Enabled check timed out\n");
2729 			return -ETIMEDOUT;
2730 		}
2731 	} else {
2732 		_regulator_delay_helper(delay);
2733 	}
2734 
2735 	trace_regulator_enable_complete(rdev_get_name(rdev));
2736 
2737 	return 0;
2738 }
2739 
2740 /**
2741  * _regulator_handle_consumer_enable - handle that a consumer enabled
2742  * @regulator: regulator source
2743  *
2744  * Some things on a regulator consumer (like the contribution towards total
2745  * load on the regulator) only have an effect when the consumer wants the
2746  * regulator enabled.  Explained in example with two consumers of the same
2747  * regulator:
2748  *   consumer A: set_load(100);       => total load = 0
2749  *   consumer A: regulator_enable();  => total load = 100
2750  *   consumer B: set_load(1000);      => total load = 100
2751  *   consumer B: regulator_enable();  => total load = 1100
2752  *   consumer A: regulator_disable(); => total_load = 1000
2753  *
2754  * This function (together with _regulator_handle_consumer_disable) is
2755  * responsible for keeping track of the refcount for a given regulator consumer
2756  * and applying / unapplying these things.
2757  *
2758  * Returns 0 upon no error; -error upon error.
2759  */
2760 static int _regulator_handle_consumer_enable(struct regulator *regulator)
2761 {
2762 	int ret;
2763 	struct regulator_dev *rdev = regulator->rdev;
2764 
2765 	lockdep_assert_held_once(&rdev->mutex.base);
2766 
2767 	regulator->enable_count++;
2768 	if (regulator->uA_load && regulator->enable_count == 1) {
2769 		ret = drms_uA_update(rdev);
2770 		if (ret)
2771 			regulator->enable_count--;
2772 		return ret;
2773 	}
2774 
2775 	return 0;
2776 }
2777 
2778 /**
2779  * _regulator_handle_consumer_disable - handle that a consumer disabled
2780  * @regulator: regulator source
2781  *
2782  * The opposite of _regulator_handle_consumer_enable().
2783  *
2784  * Returns 0 upon no error; -error upon error.
2785  */
2786 static int _regulator_handle_consumer_disable(struct regulator *regulator)
2787 {
2788 	struct regulator_dev *rdev = regulator->rdev;
2789 
2790 	lockdep_assert_held_once(&rdev->mutex.base);
2791 
2792 	if (!regulator->enable_count) {
2793 		rdev_err(rdev, "Underflow of regulator enable count\n");
2794 		return -EINVAL;
2795 	}
2796 
2797 	regulator->enable_count--;
2798 	if (regulator->uA_load && regulator->enable_count == 0)
2799 		return drms_uA_update(rdev);
2800 
2801 	return 0;
2802 }
2803 
2804 /* locks held by regulator_enable() */
2805 static int _regulator_enable(struct regulator *regulator)
2806 {
2807 	struct regulator_dev *rdev = regulator->rdev;
2808 	int ret;
2809 
2810 	lockdep_assert_held_once(&rdev->mutex.base);
2811 
2812 	if (rdev->use_count == 0 && rdev->supply) {
2813 		ret = _regulator_enable(rdev->supply);
2814 		if (ret < 0)
2815 			return ret;
2816 	}
2817 
2818 	/* balance only if there are regulators coupled */
2819 	if (rdev->coupling_desc.n_coupled > 1) {
2820 		ret = regulator_balance_voltage(rdev, PM_SUSPEND_ON);
2821 		if (ret < 0)
2822 			goto err_disable_supply;
2823 	}
2824 
2825 	ret = _regulator_handle_consumer_enable(regulator);
2826 	if (ret < 0)
2827 		goto err_disable_supply;
2828 
2829 	if (rdev->use_count == 0) {
2830 		/*
2831 		 * The regulator may already be enabled if it's not switchable
2832 		 * or was left on
2833 		 */
2834 		ret = _regulator_is_enabled(rdev);
2835 		if (ret == -EINVAL || ret == 0) {
2836 			if (!regulator_ops_is_valid(rdev,
2837 					REGULATOR_CHANGE_STATUS)) {
2838 				ret = -EPERM;
2839 				goto err_consumer_disable;
2840 			}
2841 
2842 			ret = _regulator_do_enable(rdev);
2843 			if (ret < 0)
2844 				goto err_consumer_disable;
2845 
2846 			_notifier_call_chain(rdev, REGULATOR_EVENT_ENABLE,
2847 					     NULL);
2848 		} else if (ret < 0) {
2849 			rdev_err(rdev, "is_enabled() failed: %pe\n", ERR_PTR(ret));
2850 			goto err_consumer_disable;
2851 		}
2852 		/* Fallthrough on positive return values - already enabled */
2853 	}
2854 
2855 	rdev->use_count++;
2856 
2857 	return 0;
2858 
2859 err_consumer_disable:
2860 	_regulator_handle_consumer_disable(regulator);
2861 
2862 err_disable_supply:
2863 	if (rdev->use_count == 0 && rdev->supply)
2864 		_regulator_disable(rdev->supply);
2865 
2866 	return ret;
2867 }
2868 
2869 /**
2870  * regulator_enable - enable regulator output
2871  * @regulator: regulator source
2872  *
2873  * Request that the regulator be enabled with the regulator output at
2874  * the predefined voltage or current value.  Calls to regulator_enable()
2875  * must be balanced with calls to regulator_disable().
2876  *
2877  * NOTE: the output value can be set by other drivers, boot loader or may be
2878  * hardwired in the regulator.
2879  */
2880 int regulator_enable(struct regulator *regulator)
2881 {
2882 	struct regulator_dev *rdev = regulator->rdev;
2883 	struct ww_acquire_ctx ww_ctx;
2884 	int ret;
2885 
2886 	regulator_lock_dependent(rdev, &ww_ctx);
2887 	ret = _regulator_enable(regulator);
2888 	regulator_unlock_dependent(rdev, &ww_ctx);
2889 
2890 	return ret;
2891 }
2892 EXPORT_SYMBOL_GPL(regulator_enable);
2893 
2894 static int _regulator_do_disable(struct regulator_dev *rdev)
2895 {
2896 	int ret;
2897 
2898 	trace_regulator_disable(rdev_get_name(rdev));
2899 
2900 	if (rdev->ena_pin) {
2901 		if (rdev->ena_gpio_state) {
2902 			ret = regulator_ena_gpio_ctrl(rdev, false);
2903 			if (ret < 0)
2904 				return ret;
2905 			rdev->ena_gpio_state = 0;
2906 		}
2907 
2908 	} else if (rdev->desc->ops->disable) {
2909 		ret = rdev->desc->ops->disable(rdev);
2910 		if (ret != 0)
2911 			return ret;
2912 	}
2913 
2914 	if (rdev->desc->off_on_delay)
2915 		rdev->last_off = ktime_get_boottime();
2916 
2917 	trace_regulator_disable_complete(rdev_get_name(rdev));
2918 
2919 	return 0;
2920 }
2921 
2922 /* locks held by regulator_disable() */
2923 static int _regulator_disable(struct regulator *regulator)
2924 {
2925 	struct regulator_dev *rdev = regulator->rdev;
2926 	int ret = 0;
2927 
2928 	lockdep_assert_held_once(&rdev->mutex.base);
2929 
2930 	if (WARN(rdev->use_count <= 0,
2931 		 "unbalanced disables for %s\n", rdev_get_name(rdev)))
2932 		return -EIO;
2933 
2934 	/* are we the last user and permitted to disable ? */
2935 	if (rdev->use_count == 1 &&
2936 	    (rdev->constraints && !rdev->constraints->always_on)) {
2937 
2938 		/* we are last user */
2939 		if (regulator_ops_is_valid(rdev, REGULATOR_CHANGE_STATUS)) {
2940 			ret = _notifier_call_chain(rdev,
2941 						   REGULATOR_EVENT_PRE_DISABLE,
2942 						   NULL);
2943 			if (ret & NOTIFY_STOP_MASK)
2944 				return -EINVAL;
2945 
2946 			ret = _regulator_do_disable(rdev);
2947 			if (ret < 0) {
2948 				rdev_err(rdev, "failed to disable: %pe\n", ERR_PTR(ret));
2949 				_notifier_call_chain(rdev,
2950 						REGULATOR_EVENT_ABORT_DISABLE,
2951 						NULL);
2952 				return ret;
2953 			}
2954 			_notifier_call_chain(rdev, REGULATOR_EVENT_DISABLE,
2955 					NULL);
2956 		}
2957 
2958 		rdev->use_count = 0;
2959 	} else if (rdev->use_count > 1) {
2960 		rdev->use_count--;
2961 	}
2962 
2963 	if (ret == 0)
2964 		ret = _regulator_handle_consumer_disable(regulator);
2965 
2966 	if (ret == 0 && rdev->coupling_desc.n_coupled > 1)
2967 		ret = regulator_balance_voltage(rdev, PM_SUSPEND_ON);
2968 
2969 	if (ret == 0 && rdev->use_count == 0 && rdev->supply)
2970 		ret = _regulator_disable(rdev->supply);
2971 
2972 	return ret;
2973 }
2974 
2975 /**
2976  * regulator_disable - disable regulator output
2977  * @regulator: regulator source
2978  *
2979  * Disable the regulator output voltage or current.  Calls to
2980  * regulator_enable() must be balanced with calls to
2981  * regulator_disable().
2982  *
2983  * NOTE: this will only disable the regulator output if no other consumer
2984  * devices have it enabled, the regulator device supports disabling and
2985  * machine constraints permit this operation.
2986  */
2987 int regulator_disable(struct regulator *regulator)
2988 {
2989 	struct regulator_dev *rdev = regulator->rdev;
2990 	struct ww_acquire_ctx ww_ctx;
2991 	int ret;
2992 
2993 	regulator_lock_dependent(rdev, &ww_ctx);
2994 	ret = _regulator_disable(regulator);
2995 	regulator_unlock_dependent(rdev, &ww_ctx);
2996 
2997 	return ret;
2998 }
2999 EXPORT_SYMBOL_GPL(regulator_disable);
3000 
3001 /* locks held by regulator_force_disable() */
3002 static int _regulator_force_disable(struct regulator_dev *rdev)
3003 {
3004 	int ret = 0;
3005 
3006 	lockdep_assert_held_once(&rdev->mutex.base);
3007 
3008 	ret = _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
3009 			REGULATOR_EVENT_PRE_DISABLE, NULL);
3010 	if (ret & NOTIFY_STOP_MASK)
3011 		return -EINVAL;
3012 
3013 	ret = _regulator_do_disable(rdev);
3014 	if (ret < 0) {
3015 		rdev_err(rdev, "failed to force disable: %pe\n", ERR_PTR(ret));
3016 		_notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
3017 				REGULATOR_EVENT_ABORT_DISABLE, NULL);
3018 		return ret;
3019 	}
3020 
3021 	_notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
3022 			REGULATOR_EVENT_DISABLE, NULL);
3023 
3024 	return 0;
3025 }
3026 
3027 /**
3028  * regulator_force_disable - force disable regulator output
3029  * @regulator: regulator source
3030  *
3031  * Forcibly disable the regulator output voltage or current.
3032  * NOTE: this *will* disable the regulator output even if other consumer
3033  * devices have it enabled. This should be used for situations when device
3034  * damage will likely occur if the regulator is not disabled (e.g. over temp).
3035  */
3036 int regulator_force_disable(struct regulator *regulator)
3037 {
3038 	struct regulator_dev *rdev = regulator->rdev;
3039 	struct ww_acquire_ctx ww_ctx;
3040 	int ret;
3041 
3042 	regulator_lock_dependent(rdev, &ww_ctx);
3043 
3044 	ret = _regulator_force_disable(regulator->rdev);
3045 
3046 	if (rdev->coupling_desc.n_coupled > 1)
3047 		regulator_balance_voltage(rdev, PM_SUSPEND_ON);
3048 
3049 	if (regulator->uA_load) {
3050 		regulator->uA_load = 0;
3051 		ret = drms_uA_update(rdev);
3052 	}
3053 
3054 	if (rdev->use_count != 0 && rdev->supply)
3055 		_regulator_disable(rdev->supply);
3056 
3057 	regulator_unlock_dependent(rdev, &ww_ctx);
3058 
3059 	return ret;
3060 }
3061 EXPORT_SYMBOL_GPL(regulator_force_disable);
3062 
3063 static void regulator_disable_work(struct work_struct *work)
3064 {
3065 	struct regulator_dev *rdev = container_of(work, struct regulator_dev,
3066 						  disable_work.work);
3067 	struct ww_acquire_ctx ww_ctx;
3068 	int count, i, ret;
3069 	struct regulator *regulator;
3070 	int total_count = 0;
3071 
3072 	regulator_lock_dependent(rdev, &ww_ctx);
3073 
3074 	/*
3075 	 * Workqueue functions queue the new work instance while the previous
3076 	 * work instance is being processed. Cancel the queued work instance
3077 	 * as the work instance under processing does the job of the queued
3078 	 * work instance.
3079 	 */
3080 	cancel_delayed_work(&rdev->disable_work);
3081 
3082 	list_for_each_entry(regulator, &rdev->consumer_list, list) {
3083 		count = regulator->deferred_disables;
3084 
3085 		if (!count)
3086 			continue;
3087 
3088 		total_count += count;
3089 		regulator->deferred_disables = 0;
3090 
3091 		for (i = 0; i < count; i++) {
3092 			ret = _regulator_disable(regulator);
3093 			if (ret != 0)
3094 				rdev_err(rdev, "Deferred disable failed: %pe\n",
3095 					 ERR_PTR(ret));
3096 		}
3097 	}
3098 	WARN_ON(!total_count);
3099 
3100 	if (rdev->coupling_desc.n_coupled > 1)
3101 		regulator_balance_voltage(rdev, PM_SUSPEND_ON);
3102 
3103 	regulator_unlock_dependent(rdev, &ww_ctx);
3104 }
3105 
3106 /**
3107  * regulator_disable_deferred - disable regulator output with delay
3108  * @regulator: regulator source
3109  * @ms: milliseconds until the regulator is disabled
3110  *
3111  * Execute regulator_disable() on the regulator after a delay.  This
3112  * is intended for use with devices that require some time to quiesce.
3113  *
3114  * NOTE: this will only disable the regulator output if no other consumer
3115  * devices have it enabled, the regulator device supports disabling and
3116  * machine constraints permit this operation.
3117  */
3118 int regulator_disable_deferred(struct regulator *regulator, int ms)
3119 {
3120 	struct regulator_dev *rdev = regulator->rdev;
3121 
3122 	if (!ms)
3123 		return regulator_disable(regulator);
3124 
3125 	regulator_lock(rdev);
3126 	regulator->deferred_disables++;
3127 	mod_delayed_work(system_power_efficient_wq, &rdev->disable_work,
3128 			 msecs_to_jiffies(ms));
3129 	regulator_unlock(rdev);
3130 
3131 	return 0;
3132 }
3133 EXPORT_SYMBOL_GPL(regulator_disable_deferred);
3134 
3135 static int _regulator_is_enabled(struct regulator_dev *rdev)
3136 {
3137 	/* A GPIO control always takes precedence */
3138 	if (rdev->ena_pin)
3139 		return rdev->ena_gpio_state;
3140 
3141 	/* If we don't know then assume that the regulator is always on */
3142 	if (!rdev->desc->ops->is_enabled)
3143 		return 1;
3144 
3145 	return rdev->desc->ops->is_enabled(rdev);
3146 }
3147 
3148 static int _regulator_list_voltage(struct regulator_dev *rdev,
3149 				   unsigned selector, int lock)
3150 {
3151 	const struct regulator_ops *ops = rdev->desc->ops;
3152 	int ret;
3153 
3154 	if (rdev->desc->fixed_uV && rdev->desc->n_voltages == 1 && !selector)
3155 		return rdev->desc->fixed_uV;
3156 
3157 	if (ops->list_voltage) {
3158 		if (selector >= rdev->desc->n_voltages)
3159 			return -EINVAL;
3160 		if (selector < rdev->desc->linear_min_sel)
3161 			return 0;
3162 		if (lock)
3163 			regulator_lock(rdev);
3164 		ret = ops->list_voltage(rdev, selector);
3165 		if (lock)
3166 			regulator_unlock(rdev);
3167 	} else if (rdev->is_switch && rdev->supply) {
3168 		ret = _regulator_list_voltage(rdev->supply->rdev,
3169 					      selector, lock);
3170 	} else {
3171 		return -EINVAL;
3172 	}
3173 
3174 	if (ret > 0) {
3175 		if (ret < rdev->constraints->min_uV)
3176 			ret = 0;
3177 		else if (ret > rdev->constraints->max_uV)
3178 			ret = 0;
3179 	}
3180 
3181 	return ret;
3182 }
3183 
3184 /**
3185  * regulator_is_enabled - is the regulator output enabled
3186  * @regulator: regulator source
3187  *
3188  * Returns positive if the regulator driver backing the source/client
3189  * has requested that the device be enabled, zero if it hasn't, else a
3190  * negative errno code.
3191  *
3192  * Note that the device backing this regulator handle can have multiple
3193  * users, so it might be enabled even if regulator_enable() was never
3194  * called for this particular source.
3195  */
3196 int regulator_is_enabled(struct regulator *regulator)
3197 {
3198 	int ret;
3199 
3200 	if (regulator->always_on)
3201 		return 1;
3202 
3203 	regulator_lock(regulator->rdev);
3204 	ret = _regulator_is_enabled(regulator->rdev);
3205 	regulator_unlock(regulator->rdev);
3206 
3207 	return ret;
3208 }
3209 EXPORT_SYMBOL_GPL(regulator_is_enabled);
3210 
3211 /**
3212  * regulator_count_voltages - count regulator_list_voltage() selectors
3213  * @regulator: regulator source
3214  *
3215  * Returns number of selectors, or negative errno.  Selectors are
3216  * numbered starting at zero, and typically correspond to bitfields
3217  * in hardware registers.
3218  */
3219 int regulator_count_voltages(struct regulator *regulator)
3220 {
3221 	struct regulator_dev	*rdev = regulator->rdev;
3222 
3223 	if (rdev->desc->n_voltages)
3224 		return rdev->desc->n_voltages;
3225 
3226 	if (!rdev->is_switch || !rdev->supply)
3227 		return -EINVAL;
3228 
3229 	return regulator_count_voltages(rdev->supply);
3230 }
3231 EXPORT_SYMBOL_GPL(regulator_count_voltages);
3232 
3233 /**
3234  * regulator_list_voltage - enumerate supported voltages
3235  * @regulator: regulator source
3236  * @selector: identify voltage to list
3237  * Context: can sleep
3238  *
3239  * Returns a voltage that can be passed to @regulator_set_voltage(),
3240  * zero if this selector code can't be used on this system, or a
3241  * negative errno.
3242  */
3243 int regulator_list_voltage(struct regulator *regulator, unsigned selector)
3244 {
3245 	return _regulator_list_voltage(regulator->rdev, selector, 1);
3246 }
3247 EXPORT_SYMBOL_GPL(regulator_list_voltage);
3248 
3249 /**
3250  * regulator_get_regmap - get the regulator's register map
3251  * @regulator: regulator source
3252  *
3253  * Returns the register map for the given regulator, or an ERR_PTR value
3254  * if the regulator doesn't use regmap.
3255  */
3256 struct regmap *regulator_get_regmap(struct regulator *regulator)
3257 {
3258 	struct regmap *map = regulator->rdev->regmap;
3259 
3260 	return map ? map : ERR_PTR(-EOPNOTSUPP);
3261 }
3262 
3263 /**
3264  * regulator_get_hardware_vsel_register - get the HW voltage selector register
3265  * @regulator: regulator source
3266  * @vsel_reg: voltage selector register, output parameter
3267  * @vsel_mask: mask for voltage selector bitfield, output parameter
3268  *
3269  * Returns the hardware register offset and bitmask used for setting the
3270  * regulator voltage. This might be useful when configuring voltage-scaling
3271  * hardware or firmware that can make I2C requests behind the kernel's back,
3272  * for example.
3273  *
3274  * On success, the output parameters @vsel_reg and @vsel_mask are filled in
3275  * and 0 is returned, otherwise a negative errno is returned.
3276  */
3277 int regulator_get_hardware_vsel_register(struct regulator *regulator,
3278 					 unsigned *vsel_reg,
3279 					 unsigned *vsel_mask)
3280 {
3281 	struct regulator_dev *rdev = regulator->rdev;
3282 	const struct regulator_ops *ops = rdev->desc->ops;
3283 
3284 	if (ops->set_voltage_sel != regulator_set_voltage_sel_regmap)
3285 		return -EOPNOTSUPP;
3286 
3287 	*vsel_reg = rdev->desc->vsel_reg;
3288 	*vsel_mask = rdev->desc->vsel_mask;
3289 
3290 	return 0;
3291 }
3292 EXPORT_SYMBOL_GPL(regulator_get_hardware_vsel_register);
3293 
3294 /**
3295  * regulator_list_hardware_vsel - get the HW-specific register value for a selector
3296  * @regulator: regulator source
3297  * @selector: identify voltage to list
3298  *
3299  * Converts the selector to a hardware-specific voltage selector that can be
3300  * directly written to the regulator registers. The address of the voltage
3301  * register can be determined by calling @regulator_get_hardware_vsel_register.
3302  *
3303  * On error a negative errno is returned.
3304  */
3305 int regulator_list_hardware_vsel(struct regulator *regulator,
3306 				 unsigned selector)
3307 {
3308 	struct regulator_dev *rdev = regulator->rdev;
3309 	const struct regulator_ops *ops = rdev->desc->ops;
3310 
3311 	if (selector >= rdev->desc->n_voltages)
3312 		return -EINVAL;
3313 	if (selector < rdev->desc->linear_min_sel)
3314 		return 0;
3315 	if (ops->set_voltage_sel != regulator_set_voltage_sel_regmap)
3316 		return -EOPNOTSUPP;
3317 
3318 	return selector;
3319 }
3320 EXPORT_SYMBOL_GPL(regulator_list_hardware_vsel);
3321 
3322 /**
3323  * regulator_get_linear_step - return the voltage step size between VSEL values
3324  * @regulator: regulator source
3325  *
3326  * Returns the voltage step size between VSEL values for linear
3327  * regulators, or return 0 if the regulator isn't a linear regulator.
3328  */
3329 unsigned int regulator_get_linear_step(struct regulator *regulator)
3330 {
3331 	struct regulator_dev *rdev = regulator->rdev;
3332 
3333 	return rdev->desc->uV_step;
3334 }
3335 EXPORT_SYMBOL_GPL(regulator_get_linear_step);
3336 
3337 /**
3338  * regulator_is_supported_voltage - check if a voltage range can be supported
3339  *
3340  * @regulator: Regulator to check.
3341  * @min_uV: Minimum required voltage in uV.
3342  * @max_uV: Maximum required voltage in uV.
3343  *
3344  * Returns a boolean.
3345  */
3346 int regulator_is_supported_voltage(struct regulator *regulator,
3347 				   int min_uV, int max_uV)
3348 {
3349 	struct regulator_dev *rdev = regulator->rdev;
3350 	int i, voltages, ret;
3351 
3352 	/* If we can't change voltage check the current voltage */
3353 	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE)) {
3354 		ret = regulator_get_voltage(regulator);
3355 		if (ret >= 0)
3356 			return min_uV <= ret && ret <= max_uV;
3357 		else
3358 			return ret;
3359 	}
3360 
3361 	/* Any voltage within constrains range is fine? */
3362 	if (rdev->desc->continuous_voltage_range)
3363 		return min_uV >= rdev->constraints->min_uV &&
3364 				max_uV <= rdev->constraints->max_uV;
3365 
3366 	ret = regulator_count_voltages(regulator);
3367 	if (ret < 0)
3368 		return 0;
3369 	voltages = ret;
3370 
3371 	for (i = 0; i < voltages; i++) {
3372 		ret = regulator_list_voltage(regulator, i);
3373 
3374 		if (ret >= min_uV && ret <= max_uV)
3375 			return 1;
3376 	}
3377 
3378 	return 0;
3379 }
3380 EXPORT_SYMBOL_GPL(regulator_is_supported_voltage);
3381 
3382 static int regulator_map_voltage(struct regulator_dev *rdev, int min_uV,
3383 				 int max_uV)
3384 {
3385 	const struct regulator_desc *desc = rdev->desc;
3386 
3387 	if (desc->ops->map_voltage)
3388 		return desc->ops->map_voltage(rdev, min_uV, max_uV);
3389 
3390 	if (desc->ops->list_voltage == regulator_list_voltage_linear)
3391 		return regulator_map_voltage_linear(rdev, min_uV, max_uV);
3392 
3393 	if (desc->ops->list_voltage == regulator_list_voltage_linear_range)
3394 		return regulator_map_voltage_linear_range(rdev, min_uV, max_uV);
3395 
3396 	if (desc->ops->list_voltage ==
3397 		regulator_list_voltage_pickable_linear_range)
3398 		return regulator_map_voltage_pickable_linear_range(rdev,
3399 							min_uV, max_uV);
3400 
3401 	return regulator_map_voltage_iterate(rdev, min_uV, max_uV);
3402 }
3403 
3404 static int _regulator_call_set_voltage(struct regulator_dev *rdev,
3405 				       int min_uV, int max_uV,
3406 				       unsigned *selector)
3407 {
3408 	struct pre_voltage_change_data data;
3409 	int ret;
3410 
3411 	data.old_uV = regulator_get_voltage_rdev(rdev);
3412 	data.min_uV = min_uV;
3413 	data.max_uV = max_uV;
3414 	ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE,
3415 				   &data);
3416 	if (ret & NOTIFY_STOP_MASK)
3417 		return -EINVAL;
3418 
3419 	ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV, selector);
3420 	if (ret >= 0)
3421 		return ret;
3422 
3423 	_notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE,
3424 			     (void *)data.old_uV);
3425 
3426 	return ret;
3427 }
3428 
3429 static int _regulator_call_set_voltage_sel(struct regulator_dev *rdev,
3430 					   int uV, unsigned selector)
3431 {
3432 	struct pre_voltage_change_data data;
3433 	int ret;
3434 
3435 	data.old_uV = regulator_get_voltage_rdev(rdev);
3436 	data.min_uV = uV;
3437 	data.max_uV = uV;
3438 	ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE,
3439 				   &data);
3440 	if (ret & NOTIFY_STOP_MASK)
3441 		return -EINVAL;
3442 
3443 	ret = rdev->desc->ops->set_voltage_sel(rdev, selector);
3444 	if (ret >= 0)
3445 		return ret;
3446 
3447 	_notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE,
3448 			     (void *)data.old_uV);
3449 
3450 	return ret;
3451 }
3452 
3453 static int _regulator_set_voltage_sel_step(struct regulator_dev *rdev,
3454 					   int uV, int new_selector)
3455 {
3456 	const struct regulator_ops *ops = rdev->desc->ops;
3457 	int diff, old_sel, curr_sel, ret;
3458 
3459 	/* Stepping is only needed if the regulator is enabled. */
3460 	if (!_regulator_is_enabled(rdev))
3461 		goto final_set;
3462 
3463 	if (!ops->get_voltage_sel)
3464 		return -EINVAL;
3465 
3466 	old_sel = ops->get_voltage_sel(rdev);
3467 	if (old_sel < 0)
3468 		return old_sel;
3469 
3470 	diff = new_selector - old_sel;
3471 	if (diff == 0)
3472 		return 0; /* No change needed. */
3473 
3474 	if (diff > 0) {
3475 		/* Stepping up. */
3476 		for (curr_sel = old_sel + rdev->desc->vsel_step;
3477 		     curr_sel < new_selector;
3478 		     curr_sel += rdev->desc->vsel_step) {
3479 			/*
3480 			 * Call the callback directly instead of using
3481 			 * _regulator_call_set_voltage_sel() as we don't
3482 			 * want to notify anyone yet. Same in the branch
3483 			 * below.
3484 			 */
3485 			ret = ops->set_voltage_sel(rdev, curr_sel);
3486 			if (ret)
3487 				goto try_revert;
3488 		}
3489 	} else {
3490 		/* Stepping down. */
3491 		for (curr_sel = old_sel - rdev->desc->vsel_step;
3492 		     curr_sel > new_selector;
3493 		     curr_sel -= rdev->desc->vsel_step) {
3494 			ret = ops->set_voltage_sel(rdev, curr_sel);
3495 			if (ret)
3496 				goto try_revert;
3497 		}
3498 	}
3499 
3500 final_set:
3501 	/* The final selector will trigger the notifiers. */
3502 	return _regulator_call_set_voltage_sel(rdev, uV, new_selector);
3503 
3504 try_revert:
3505 	/*
3506 	 * At least try to return to the previous voltage if setting a new
3507 	 * one failed.
3508 	 */
3509 	(void)ops->set_voltage_sel(rdev, old_sel);
3510 	return ret;
3511 }
3512 
3513 static int _regulator_set_voltage_time(struct regulator_dev *rdev,
3514 				       int old_uV, int new_uV)
3515 {
3516 	unsigned int ramp_delay = 0;
3517 
3518 	if (rdev->constraints->ramp_delay)
3519 		ramp_delay = rdev->constraints->ramp_delay;
3520 	else if (rdev->desc->ramp_delay)
3521 		ramp_delay = rdev->desc->ramp_delay;
3522 	else if (rdev->constraints->settling_time)
3523 		return rdev->constraints->settling_time;
3524 	else if (rdev->constraints->settling_time_up &&
3525 		 (new_uV > old_uV))
3526 		return rdev->constraints->settling_time_up;
3527 	else if (rdev->constraints->settling_time_down &&
3528 		 (new_uV < old_uV))
3529 		return rdev->constraints->settling_time_down;
3530 
3531 	if (ramp_delay == 0)
3532 		return 0;
3533 
3534 	return DIV_ROUND_UP(abs(new_uV - old_uV), ramp_delay);
3535 }
3536 
3537 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
3538 				     int min_uV, int max_uV)
3539 {
3540 	int ret;
3541 	int delay = 0;
3542 	int best_val = 0;
3543 	unsigned int selector;
3544 	int old_selector = -1;
3545 	const struct regulator_ops *ops = rdev->desc->ops;
3546 	int old_uV = regulator_get_voltage_rdev(rdev);
3547 
3548 	trace_regulator_set_voltage(rdev_get_name(rdev), min_uV, max_uV);
3549 
3550 	min_uV += rdev->constraints->uV_offset;
3551 	max_uV += rdev->constraints->uV_offset;
3552 
3553 	/*
3554 	 * If we can't obtain the old selector there is not enough
3555 	 * info to call set_voltage_time_sel().
3556 	 */
3557 	if (_regulator_is_enabled(rdev) &&
3558 	    ops->set_voltage_time_sel && ops->get_voltage_sel) {
3559 		old_selector = ops->get_voltage_sel(rdev);
3560 		if (old_selector < 0)
3561 			return old_selector;
3562 	}
3563 
3564 	if (ops->set_voltage) {
3565 		ret = _regulator_call_set_voltage(rdev, min_uV, max_uV,
3566 						  &selector);
3567 
3568 		if (ret >= 0) {
3569 			if (ops->list_voltage)
3570 				best_val = ops->list_voltage(rdev,
3571 							     selector);
3572 			else
3573 				best_val = regulator_get_voltage_rdev(rdev);
3574 		}
3575 
3576 	} else if (ops->set_voltage_sel) {
3577 		ret = regulator_map_voltage(rdev, min_uV, max_uV);
3578 		if (ret >= 0) {
3579 			best_val = ops->list_voltage(rdev, ret);
3580 			if (min_uV <= best_val && max_uV >= best_val) {
3581 				selector = ret;
3582 				if (old_selector == selector)
3583 					ret = 0;
3584 				else if (rdev->desc->vsel_step)
3585 					ret = _regulator_set_voltage_sel_step(
3586 						rdev, best_val, selector);
3587 				else
3588 					ret = _regulator_call_set_voltage_sel(
3589 						rdev, best_val, selector);
3590 			} else {
3591 				ret = -EINVAL;
3592 			}
3593 		}
3594 	} else {
3595 		ret = -EINVAL;
3596 	}
3597 
3598 	if (ret)
3599 		goto out;
3600 
3601 	if (ops->set_voltage_time_sel) {
3602 		/*
3603 		 * Call set_voltage_time_sel if successfully obtained
3604 		 * old_selector
3605 		 */
3606 		if (old_selector >= 0 && old_selector != selector)
3607 			delay = ops->set_voltage_time_sel(rdev, old_selector,
3608 							  selector);
3609 	} else {
3610 		if (old_uV != best_val) {
3611 			if (ops->set_voltage_time)
3612 				delay = ops->set_voltage_time(rdev, old_uV,
3613 							      best_val);
3614 			else
3615 				delay = _regulator_set_voltage_time(rdev,
3616 								    old_uV,
3617 								    best_val);
3618 		}
3619 	}
3620 
3621 	if (delay < 0) {
3622 		rdev_warn(rdev, "failed to get delay: %pe\n", ERR_PTR(delay));
3623 		delay = 0;
3624 	}
3625 
3626 	/* Insert any necessary delays */
3627 	_regulator_delay_helper(delay);
3628 
3629 	if (best_val >= 0) {
3630 		unsigned long data = best_val;
3631 
3632 		_notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE,
3633 				     (void *)data);
3634 	}
3635 
3636 out:
3637 	trace_regulator_set_voltage_complete(rdev_get_name(rdev), best_val);
3638 
3639 	return ret;
3640 }
3641 
3642 static int _regulator_do_set_suspend_voltage(struct regulator_dev *rdev,
3643 				  int min_uV, int max_uV, suspend_state_t state)
3644 {
3645 	struct regulator_state *rstate;
3646 	int uV, sel;
3647 
3648 	rstate = regulator_get_suspend_state(rdev, state);
3649 	if (rstate == NULL)
3650 		return -EINVAL;
3651 
3652 	if (min_uV < rstate->min_uV)
3653 		min_uV = rstate->min_uV;
3654 	if (max_uV > rstate->max_uV)
3655 		max_uV = rstate->max_uV;
3656 
3657 	sel = regulator_map_voltage(rdev, min_uV, max_uV);
3658 	if (sel < 0)
3659 		return sel;
3660 
3661 	uV = rdev->desc->ops->list_voltage(rdev, sel);
3662 	if (uV >= min_uV && uV <= max_uV)
3663 		rstate->uV = uV;
3664 
3665 	return 0;
3666 }
3667 
3668 static int regulator_set_voltage_unlocked(struct regulator *regulator,
3669 					  int min_uV, int max_uV,
3670 					  suspend_state_t state)
3671 {
3672 	struct regulator_dev *rdev = regulator->rdev;
3673 	struct regulator_voltage *voltage = &regulator->voltage[state];
3674 	int ret = 0;
3675 	int old_min_uV, old_max_uV;
3676 	int current_uV;
3677 
3678 	/* If we're setting the same range as last time the change
3679 	 * should be a noop (some cpufreq implementations use the same
3680 	 * voltage for multiple frequencies, for example).
3681 	 */
3682 	if (voltage->min_uV == min_uV && voltage->max_uV == max_uV)
3683 		goto out;
3684 
3685 	/* If we're trying to set a range that overlaps the current voltage,
3686 	 * return successfully even though the regulator does not support
3687 	 * changing the voltage.
3688 	 */
3689 	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE)) {
3690 		current_uV = regulator_get_voltage_rdev(rdev);
3691 		if (min_uV <= current_uV && current_uV <= max_uV) {
3692 			voltage->min_uV = min_uV;
3693 			voltage->max_uV = max_uV;
3694 			goto out;
3695 		}
3696 	}
3697 
3698 	/* sanity check */
3699 	if (!rdev->desc->ops->set_voltage &&
3700 	    !rdev->desc->ops->set_voltage_sel) {
3701 		ret = -EINVAL;
3702 		goto out;
3703 	}
3704 
3705 	/* constraints check */
3706 	ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
3707 	if (ret < 0)
3708 		goto out;
3709 
3710 	/* restore original values in case of error */
3711 	old_min_uV = voltage->min_uV;
3712 	old_max_uV = voltage->max_uV;
3713 	voltage->min_uV = min_uV;
3714 	voltage->max_uV = max_uV;
3715 
3716 	/* for not coupled regulators this will just set the voltage */
3717 	ret = regulator_balance_voltage(rdev, state);
3718 	if (ret < 0) {
3719 		voltage->min_uV = old_min_uV;
3720 		voltage->max_uV = old_max_uV;
3721 	}
3722 
3723 out:
3724 	return ret;
3725 }
3726 
3727 int regulator_set_voltage_rdev(struct regulator_dev *rdev, int min_uV,
3728 			       int max_uV, suspend_state_t state)
3729 {
3730 	int best_supply_uV = 0;
3731 	int supply_change_uV = 0;
3732 	int ret;
3733 
3734 	if (rdev->supply &&
3735 	    regulator_ops_is_valid(rdev->supply->rdev,
3736 				   REGULATOR_CHANGE_VOLTAGE) &&
3737 	    (rdev->desc->min_dropout_uV || !(rdev->desc->ops->get_voltage ||
3738 					   rdev->desc->ops->get_voltage_sel))) {
3739 		int current_supply_uV;
3740 		int selector;
3741 
3742 		selector = regulator_map_voltage(rdev, min_uV, max_uV);
3743 		if (selector < 0) {
3744 			ret = selector;
3745 			goto out;
3746 		}
3747 
3748 		best_supply_uV = _regulator_list_voltage(rdev, selector, 0);
3749 		if (best_supply_uV < 0) {
3750 			ret = best_supply_uV;
3751 			goto out;
3752 		}
3753 
3754 		best_supply_uV += rdev->desc->min_dropout_uV;
3755 
3756 		current_supply_uV = regulator_get_voltage_rdev(rdev->supply->rdev);
3757 		if (current_supply_uV < 0) {
3758 			ret = current_supply_uV;
3759 			goto out;
3760 		}
3761 
3762 		supply_change_uV = best_supply_uV - current_supply_uV;
3763 	}
3764 
3765 	if (supply_change_uV > 0) {
3766 		ret = regulator_set_voltage_unlocked(rdev->supply,
3767 				best_supply_uV, INT_MAX, state);
3768 		if (ret) {
3769 			dev_err(&rdev->dev, "Failed to increase supply voltage: %pe\n",
3770 				ERR_PTR(ret));
3771 			goto out;
3772 		}
3773 	}
3774 
3775 	if (state == PM_SUSPEND_ON)
3776 		ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
3777 	else
3778 		ret = _regulator_do_set_suspend_voltage(rdev, min_uV,
3779 							max_uV, state);
3780 	if (ret < 0)
3781 		goto out;
3782 
3783 	if (supply_change_uV < 0) {
3784 		ret = regulator_set_voltage_unlocked(rdev->supply,
3785 				best_supply_uV, INT_MAX, state);
3786 		if (ret)
3787 			dev_warn(&rdev->dev, "Failed to decrease supply voltage: %pe\n",
3788 				 ERR_PTR(ret));
3789 		/* No need to fail here */
3790 		ret = 0;
3791 	}
3792 
3793 out:
3794 	return ret;
3795 }
3796 EXPORT_SYMBOL_GPL(regulator_set_voltage_rdev);
3797 
3798 static int regulator_limit_voltage_step(struct regulator_dev *rdev,
3799 					int *current_uV, int *min_uV)
3800 {
3801 	struct regulation_constraints *constraints = rdev->constraints;
3802 
3803 	/* Limit voltage change only if necessary */
3804 	if (!constraints->max_uV_step || !_regulator_is_enabled(rdev))
3805 		return 1;
3806 
3807 	if (*current_uV < 0) {
3808 		*current_uV = regulator_get_voltage_rdev(rdev);
3809 
3810 		if (*current_uV < 0)
3811 			return *current_uV;
3812 	}
3813 
3814 	if (abs(*current_uV - *min_uV) <= constraints->max_uV_step)
3815 		return 1;
3816 
3817 	/* Clamp target voltage within the given step */
3818 	if (*current_uV < *min_uV)
3819 		*min_uV = min(*current_uV + constraints->max_uV_step,
3820 			      *min_uV);
3821 	else
3822 		*min_uV = max(*current_uV - constraints->max_uV_step,
3823 			      *min_uV);
3824 
3825 	return 0;
3826 }
3827 
3828 static int regulator_get_optimal_voltage(struct regulator_dev *rdev,
3829 					 int *current_uV,
3830 					 int *min_uV, int *max_uV,
3831 					 suspend_state_t state,
3832 					 int n_coupled)
3833 {
3834 	struct coupling_desc *c_desc = &rdev->coupling_desc;
3835 	struct regulator_dev **c_rdevs = c_desc->coupled_rdevs;
3836 	struct regulation_constraints *constraints = rdev->constraints;
3837 	int desired_min_uV = 0, desired_max_uV = INT_MAX;
3838 	int max_current_uV = 0, min_current_uV = INT_MAX;
3839 	int highest_min_uV = 0, target_uV, possible_uV;
3840 	int i, ret, max_spread;
3841 	bool done;
3842 
3843 	*current_uV = -1;
3844 
3845 	/*
3846 	 * If there are no coupled regulators, simply set the voltage
3847 	 * demanded by consumers.
3848 	 */
3849 	if (n_coupled == 1) {
3850 		/*
3851 		 * If consumers don't provide any demands, set voltage
3852 		 * to min_uV
3853 		 */
3854 		desired_min_uV = constraints->min_uV;
3855 		desired_max_uV = constraints->max_uV;
3856 
3857 		ret = regulator_check_consumers(rdev,
3858 						&desired_min_uV,
3859 						&desired_max_uV, state);
3860 		if (ret < 0)
3861 			return ret;
3862 
3863 		possible_uV = desired_min_uV;
3864 		done = true;
3865 
3866 		goto finish;
3867 	}
3868 
3869 	/* Find highest min desired voltage */
3870 	for (i = 0; i < n_coupled; i++) {
3871 		int tmp_min = 0;
3872 		int tmp_max = INT_MAX;
3873 
3874 		lockdep_assert_held_once(&c_rdevs[i]->mutex.base);
3875 
3876 		ret = regulator_check_consumers(c_rdevs[i],
3877 						&tmp_min,
3878 						&tmp_max, state);
3879 		if (ret < 0)
3880 			return ret;
3881 
3882 		ret = regulator_check_voltage(c_rdevs[i], &tmp_min, &tmp_max);
3883 		if (ret < 0)
3884 			return ret;
3885 
3886 		highest_min_uV = max(highest_min_uV, tmp_min);
3887 
3888 		if (i == 0) {
3889 			desired_min_uV = tmp_min;
3890 			desired_max_uV = tmp_max;
3891 		}
3892 	}
3893 
3894 	max_spread = constraints->max_spread[0];
3895 
3896 	/*
3897 	 * Let target_uV be equal to the desired one if possible.
3898 	 * If not, set it to minimum voltage, allowed by other coupled
3899 	 * regulators.
3900 	 */
3901 	target_uV = max(desired_min_uV, highest_min_uV - max_spread);
3902 
3903 	/*
3904 	 * Find min and max voltages, which currently aren't violating
3905 	 * max_spread.
3906 	 */
3907 	for (i = 1; i < n_coupled; i++) {
3908 		int tmp_act;
3909 
3910 		if (!_regulator_is_enabled(c_rdevs[i]))
3911 			continue;
3912 
3913 		tmp_act = regulator_get_voltage_rdev(c_rdevs[i]);
3914 		if (tmp_act < 0)
3915 			return tmp_act;
3916 
3917 		min_current_uV = min(tmp_act, min_current_uV);
3918 		max_current_uV = max(tmp_act, max_current_uV);
3919 	}
3920 
3921 	/* There aren't any other regulators enabled */
3922 	if (max_current_uV == 0) {
3923 		possible_uV = target_uV;
3924 	} else {
3925 		/*
3926 		 * Correct target voltage, so as it currently isn't
3927 		 * violating max_spread
3928 		 */
3929 		possible_uV = max(target_uV, max_current_uV - max_spread);
3930 		possible_uV = min(possible_uV, min_current_uV + max_spread);
3931 	}
3932 
3933 	if (possible_uV > desired_max_uV)
3934 		return -EINVAL;
3935 
3936 	done = (possible_uV == target_uV);
3937 	desired_min_uV = possible_uV;
3938 
3939 finish:
3940 	/* Apply max_uV_step constraint if necessary */
3941 	if (state == PM_SUSPEND_ON) {
3942 		ret = regulator_limit_voltage_step(rdev, current_uV,
3943 						   &desired_min_uV);
3944 		if (ret < 0)
3945 			return ret;
3946 
3947 		if (ret == 0)
3948 			done = false;
3949 	}
3950 
3951 	/* Set current_uV if wasn't done earlier in the code and if necessary */
3952 	if (n_coupled > 1 && *current_uV == -1) {
3953 
3954 		if (_regulator_is_enabled(rdev)) {
3955 			ret = regulator_get_voltage_rdev(rdev);
3956 			if (ret < 0)
3957 				return ret;
3958 
3959 			*current_uV = ret;
3960 		} else {
3961 			*current_uV = desired_min_uV;
3962 		}
3963 	}
3964 
3965 	*min_uV = desired_min_uV;
3966 	*max_uV = desired_max_uV;
3967 
3968 	return done;
3969 }
3970 
3971 int regulator_do_balance_voltage(struct regulator_dev *rdev,
3972 				 suspend_state_t state, bool skip_coupled)
3973 {
3974 	struct regulator_dev **c_rdevs;
3975 	struct regulator_dev *best_rdev;
3976 	struct coupling_desc *c_desc = &rdev->coupling_desc;
3977 	int i, ret, n_coupled, best_min_uV, best_max_uV, best_c_rdev;
3978 	unsigned int delta, best_delta;
3979 	unsigned long c_rdev_done = 0;
3980 	bool best_c_rdev_done;
3981 
3982 	c_rdevs = c_desc->coupled_rdevs;
3983 	n_coupled = skip_coupled ? 1 : c_desc->n_coupled;
3984 
3985 	/*
3986 	 * Find the best possible voltage change on each loop. Leave the loop
3987 	 * if there isn't any possible change.
3988 	 */
3989 	do {
3990 		best_c_rdev_done = false;
3991 		best_delta = 0;
3992 		best_min_uV = 0;
3993 		best_max_uV = 0;
3994 		best_c_rdev = 0;
3995 		best_rdev = NULL;
3996 
3997 		/*
3998 		 * Find highest difference between optimal voltage
3999 		 * and current voltage.
4000 		 */
4001 		for (i = 0; i < n_coupled; i++) {
4002 			/*
4003 			 * optimal_uV is the best voltage that can be set for
4004 			 * i-th regulator at the moment without violating
4005 			 * max_spread constraint in order to balance
4006 			 * the coupled voltages.
4007 			 */
4008 			int optimal_uV = 0, optimal_max_uV = 0, current_uV = 0;
4009 
4010 			if (test_bit(i, &c_rdev_done))
4011 				continue;
4012 
4013 			ret = regulator_get_optimal_voltage(c_rdevs[i],
4014 							    &current_uV,
4015 							    &optimal_uV,
4016 							    &optimal_max_uV,
4017 							    state, n_coupled);
4018 			if (ret < 0)
4019 				goto out;
4020 
4021 			delta = abs(optimal_uV - current_uV);
4022 
4023 			if (delta && best_delta <= delta) {
4024 				best_c_rdev_done = ret;
4025 				best_delta = delta;
4026 				best_rdev = c_rdevs[i];
4027 				best_min_uV = optimal_uV;
4028 				best_max_uV = optimal_max_uV;
4029 				best_c_rdev = i;
4030 			}
4031 		}
4032 
4033 		/* Nothing to change, return successfully */
4034 		if (!best_rdev) {
4035 			ret = 0;
4036 			goto out;
4037 		}
4038 
4039 		ret = regulator_set_voltage_rdev(best_rdev, best_min_uV,
4040 						 best_max_uV, state);
4041 
4042 		if (ret < 0)
4043 			goto out;
4044 
4045 		if (best_c_rdev_done)
4046 			set_bit(best_c_rdev, &c_rdev_done);
4047 
4048 	} while (n_coupled > 1);
4049 
4050 out:
4051 	return ret;
4052 }
4053 
4054 static int regulator_balance_voltage(struct regulator_dev *rdev,
4055 				     suspend_state_t state)
4056 {
4057 	struct coupling_desc *c_desc = &rdev->coupling_desc;
4058 	struct regulator_coupler *coupler = c_desc->coupler;
4059 	bool skip_coupled = false;
4060 
4061 	/*
4062 	 * If system is in a state other than PM_SUSPEND_ON, don't check
4063 	 * other coupled regulators.
4064 	 */
4065 	if (state != PM_SUSPEND_ON)
4066 		skip_coupled = true;
4067 
4068 	if (c_desc->n_resolved < c_desc->n_coupled) {
4069 		rdev_err(rdev, "Not all coupled regulators registered\n");
4070 		return -EPERM;
4071 	}
4072 
4073 	/* Invoke custom balancer for customized couplers */
4074 	if (coupler && coupler->balance_voltage)
4075 		return coupler->balance_voltage(coupler, rdev, state);
4076 
4077 	return regulator_do_balance_voltage(rdev, state, skip_coupled);
4078 }
4079 
4080 /**
4081  * regulator_set_voltage - set regulator output voltage
4082  * @regulator: regulator source
4083  * @min_uV: Minimum required voltage in uV
4084  * @max_uV: Maximum acceptable voltage in uV
4085  *
4086  * Sets a voltage regulator to the desired output voltage. This can be set
4087  * during any regulator state. IOW, regulator can be disabled or enabled.
4088  *
4089  * If the regulator is enabled then the voltage will change to the new value
4090  * immediately otherwise if the regulator is disabled the regulator will
4091  * output at the new voltage when enabled.
4092  *
4093  * NOTE: If the regulator is shared between several devices then the lowest
4094  * request voltage that meets the system constraints will be used.
4095  * Regulator system constraints must be set for this regulator before
4096  * calling this function otherwise this call will fail.
4097  */
4098 int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
4099 {
4100 	struct ww_acquire_ctx ww_ctx;
4101 	int ret;
4102 
4103 	regulator_lock_dependent(regulator->rdev, &ww_ctx);
4104 
4105 	ret = regulator_set_voltage_unlocked(regulator, min_uV, max_uV,
4106 					     PM_SUSPEND_ON);
4107 
4108 	regulator_unlock_dependent(regulator->rdev, &ww_ctx);
4109 
4110 	return ret;
4111 }
4112 EXPORT_SYMBOL_GPL(regulator_set_voltage);
4113 
4114 static inline int regulator_suspend_toggle(struct regulator_dev *rdev,
4115 					   suspend_state_t state, bool en)
4116 {
4117 	struct regulator_state *rstate;
4118 
4119 	rstate = regulator_get_suspend_state(rdev, state);
4120 	if (rstate == NULL)
4121 		return -EINVAL;
4122 
4123 	if (!rstate->changeable)
4124 		return -EPERM;
4125 
4126 	rstate->enabled = (en) ? ENABLE_IN_SUSPEND : DISABLE_IN_SUSPEND;
4127 
4128 	return 0;
4129 }
4130 
4131 int regulator_suspend_enable(struct regulator_dev *rdev,
4132 				    suspend_state_t state)
4133 {
4134 	return regulator_suspend_toggle(rdev, state, true);
4135 }
4136 EXPORT_SYMBOL_GPL(regulator_suspend_enable);
4137 
4138 int regulator_suspend_disable(struct regulator_dev *rdev,
4139 				     suspend_state_t state)
4140 {
4141 	struct regulator *regulator;
4142 	struct regulator_voltage *voltage;
4143 
4144 	/*
4145 	 * if any consumer wants this regulator device keeping on in
4146 	 * suspend states, don't set it as disabled.
4147 	 */
4148 	list_for_each_entry(regulator, &rdev->consumer_list, list) {
4149 		voltage = &regulator->voltage[state];
4150 		if (voltage->min_uV || voltage->max_uV)
4151 			return 0;
4152 	}
4153 
4154 	return regulator_suspend_toggle(rdev, state, false);
4155 }
4156 EXPORT_SYMBOL_GPL(regulator_suspend_disable);
4157 
4158 static int _regulator_set_suspend_voltage(struct regulator *regulator,
4159 					  int min_uV, int max_uV,
4160 					  suspend_state_t state)
4161 {
4162 	struct regulator_dev *rdev = regulator->rdev;
4163 	struct regulator_state *rstate;
4164 
4165 	rstate = regulator_get_suspend_state(rdev, state);
4166 	if (rstate == NULL)
4167 		return -EINVAL;
4168 
4169 	if (rstate->min_uV == rstate->max_uV) {
4170 		rdev_err(rdev, "The suspend voltage can't be changed!\n");
4171 		return -EPERM;
4172 	}
4173 
4174 	return regulator_set_voltage_unlocked(regulator, min_uV, max_uV, state);
4175 }
4176 
4177 int regulator_set_suspend_voltage(struct regulator *regulator, int min_uV,
4178 				  int max_uV, suspend_state_t state)
4179 {
4180 	struct ww_acquire_ctx ww_ctx;
4181 	int ret;
4182 
4183 	/* PM_SUSPEND_ON is handled by regulator_set_voltage() */
4184 	if (regulator_check_states(state) || state == PM_SUSPEND_ON)
4185 		return -EINVAL;
4186 
4187 	regulator_lock_dependent(regulator->rdev, &ww_ctx);
4188 
4189 	ret = _regulator_set_suspend_voltage(regulator, min_uV,
4190 					     max_uV, state);
4191 
4192 	regulator_unlock_dependent(regulator->rdev, &ww_ctx);
4193 
4194 	return ret;
4195 }
4196 EXPORT_SYMBOL_GPL(regulator_set_suspend_voltage);
4197 
4198 /**
4199  * regulator_set_voltage_time - get raise/fall time
4200  * @regulator: regulator source
4201  * @old_uV: starting voltage in microvolts
4202  * @new_uV: target voltage in microvolts
4203  *
4204  * Provided with the starting and ending voltage, this function attempts to
4205  * calculate the time in microseconds required to rise or fall to this new
4206  * voltage.
4207  */
4208 int regulator_set_voltage_time(struct regulator *regulator,
4209 			       int old_uV, int new_uV)
4210 {
4211 	struct regulator_dev *rdev = regulator->rdev;
4212 	const struct regulator_ops *ops = rdev->desc->ops;
4213 	int old_sel = -1;
4214 	int new_sel = -1;
4215 	int voltage;
4216 	int i;
4217 
4218 	if (ops->set_voltage_time)
4219 		return ops->set_voltage_time(rdev, old_uV, new_uV);
4220 	else if (!ops->set_voltage_time_sel)
4221 		return _regulator_set_voltage_time(rdev, old_uV, new_uV);
4222 
4223 	/* Currently requires operations to do this */
4224 	if (!ops->list_voltage || !rdev->desc->n_voltages)
4225 		return -EINVAL;
4226 
4227 	for (i = 0; i < rdev->desc->n_voltages; i++) {
4228 		/* We only look for exact voltage matches here */
4229 		if (i < rdev->desc->linear_min_sel)
4230 			continue;
4231 
4232 		if (old_sel >= 0 && new_sel >= 0)
4233 			break;
4234 
4235 		voltage = regulator_list_voltage(regulator, i);
4236 		if (voltage < 0)
4237 			return -EINVAL;
4238 		if (voltage == 0)
4239 			continue;
4240 		if (voltage == old_uV)
4241 			old_sel = i;
4242 		if (voltage == new_uV)
4243 			new_sel = i;
4244 	}
4245 
4246 	if (old_sel < 0 || new_sel < 0)
4247 		return -EINVAL;
4248 
4249 	return ops->set_voltage_time_sel(rdev, old_sel, new_sel);
4250 }
4251 EXPORT_SYMBOL_GPL(regulator_set_voltage_time);
4252 
4253 /**
4254  * regulator_set_voltage_time_sel - get raise/fall time
4255  * @rdev: regulator source device
4256  * @old_selector: selector for starting voltage
4257  * @new_selector: selector for target voltage
4258  *
4259  * Provided with the starting and target voltage selectors, this function
4260  * returns time in microseconds required to rise or fall to this new voltage
4261  *
4262  * Drivers providing ramp_delay in regulation_constraints can use this as their
4263  * set_voltage_time_sel() operation.
4264  */
4265 int regulator_set_voltage_time_sel(struct regulator_dev *rdev,
4266 				   unsigned int old_selector,
4267 				   unsigned int new_selector)
4268 {
4269 	int old_volt, new_volt;
4270 
4271 	/* sanity check */
4272 	if (!rdev->desc->ops->list_voltage)
4273 		return -EINVAL;
4274 
4275 	old_volt = rdev->desc->ops->list_voltage(rdev, old_selector);
4276 	new_volt = rdev->desc->ops->list_voltage(rdev, new_selector);
4277 
4278 	if (rdev->desc->ops->set_voltage_time)
4279 		return rdev->desc->ops->set_voltage_time(rdev, old_volt,
4280 							 new_volt);
4281 	else
4282 		return _regulator_set_voltage_time(rdev, old_volt, new_volt);
4283 }
4284 EXPORT_SYMBOL_GPL(regulator_set_voltage_time_sel);
4285 
4286 int regulator_sync_voltage_rdev(struct regulator_dev *rdev)
4287 {
4288 	int ret;
4289 
4290 	regulator_lock(rdev);
4291 
4292 	if (!rdev->desc->ops->set_voltage &&
4293 	    !rdev->desc->ops->set_voltage_sel) {
4294 		ret = -EINVAL;
4295 		goto out;
4296 	}
4297 
4298 	/* balance only, if regulator is coupled */
4299 	if (rdev->coupling_desc.n_coupled > 1)
4300 		ret = regulator_balance_voltage(rdev, PM_SUSPEND_ON);
4301 	else
4302 		ret = -EOPNOTSUPP;
4303 
4304 out:
4305 	regulator_unlock(rdev);
4306 	return ret;
4307 }
4308 
4309 /**
4310  * regulator_sync_voltage - re-apply last regulator output voltage
4311  * @regulator: regulator source
4312  *
4313  * Re-apply the last configured voltage.  This is intended to be used
4314  * where some external control source the consumer is cooperating with
4315  * has caused the configured voltage to change.
4316  */
4317 int regulator_sync_voltage(struct regulator *regulator)
4318 {
4319 	struct regulator_dev *rdev = regulator->rdev;
4320 	struct regulator_voltage *voltage = &regulator->voltage[PM_SUSPEND_ON];
4321 	int ret, min_uV, max_uV;
4322 
4323 	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE))
4324 		return 0;
4325 
4326 	regulator_lock(rdev);
4327 
4328 	if (!rdev->desc->ops->set_voltage &&
4329 	    !rdev->desc->ops->set_voltage_sel) {
4330 		ret = -EINVAL;
4331 		goto out;
4332 	}
4333 
4334 	/* This is only going to work if we've had a voltage configured. */
4335 	if (!voltage->min_uV && !voltage->max_uV) {
4336 		ret = -EINVAL;
4337 		goto out;
4338 	}
4339 
4340 	min_uV = voltage->min_uV;
4341 	max_uV = voltage->max_uV;
4342 
4343 	/* This should be a paranoia check... */
4344 	ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
4345 	if (ret < 0)
4346 		goto out;
4347 
4348 	ret = regulator_check_consumers(rdev, &min_uV, &max_uV, 0);
4349 	if (ret < 0)
4350 		goto out;
4351 
4352 	/* balance only, if regulator is coupled */
4353 	if (rdev->coupling_desc.n_coupled > 1)
4354 		ret = regulator_balance_voltage(rdev, PM_SUSPEND_ON);
4355 	else
4356 		ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
4357 
4358 out:
4359 	regulator_unlock(rdev);
4360 	return ret;
4361 }
4362 EXPORT_SYMBOL_GPL(regulator_sync_voltage);
4363 
4364 int regulator_get_voltage_rdev(struct regulator_dev *rdev)
4365 {
4366 	int sel, ret;
4367 	bool bypassed;
4368 
4369 	if (rdev->desc->ops->get_bypass) {
4370 		ret = rdev->desc->ops->get_bypass(rdev, &bypassed);
4371 		if (ret < 0)
4372 			return ret;
4373 		if (bypassed) {
4374 			/* if bypassed the regulator must have a supply */
4375 			if (!rdev->supply) {
4376 				rdev_err(rdev,
4377 					 "bypassed regulator has no supply!\n");
4378 				return -EPROBE_DEFER;
4379 			}
4380 
4381 			return regulator_get_voltage_rdev(rdev->supply->rdev);
4382 		}
4383 	}
4384 
4385 	if (rdev->desc->ops->get_voltage_sel) {
4386 		sel = rdev->desc->ops->get_voltage_sel(rdev);
4387 		if (sel < 0)
4388 			return sel;
4389 		ret = rdev->desc->ops->list_voltage(rdev, sel);
4390 	} else if (rdev->desc->ops->get_voltage) {
4391 		ret = rdev->desc->ops->get_voltage(rdev);
4392 	} else if (rdev->desc->ops->list_voltage) {
4393 		ret = rdev->desc->ops->list_voltage(rdev, 0);
4394 	} else if (rdev->desc->fixed_uV && (rdev->desc->n_voltages == 1)) {
4395 		ret = rdev->desc->fixed_uV;
4396 	} else if (rdev->supply) {
4397 		ret = regulator_get_voltage_rdev(rdev->supply->rdev);
4398 	} else if (rdev->supply_name) {
4399 		return -EPROBE_DEFER;
4400 	} else {
4401 		return -EINVAL;
4402 	}
4403 
4404 	if (ret < 0)
4405 		return ret;
4406 	return ret - rdev->constraints->uV_offset;
4407 }
4408 EXPORT_SYMBOL_GPL(regulator_get_voltage_rdev);
4409 
4410 /**
4411  * regulator_get_voltage - get regulator output voltage
4412  * @regulator: regulator source
4413  *
4414  * This returns the current regulator voltage in uV.
4415  *
4416  * NOTE: If the regulator is disabled it will return the voltage value. This
4417  * function should not be used to determine regulator state.
4418  */
4419 int regulator_get_voltage(struct regulator *regulator)
4420 {
4421 	struct ww_acquire_ctx ww_ctx;
4422 	int ret;
4423 
4424 	regulator_lock_dependent(regulator->rdev, &ww_ctx);
4425 	ret = regulator_get_voltage_rdev(regulator->rdev);
4426 	regulator_unlock_dependent(regulator->rdev, &ww_ctx);
4427 
4428 	return ret;
4429 }
4430 EXPORT_SYMBOL_GPL(regulator_get_voltage);
4431 
4432 /**
4433  * regulator_set_current_limit - set regulator output current limit
4434  * @regulator: regulator source
4435  * @min_uA: Minimum supported current in uA
4436  * @max_uA: Maximum supported current in uA
4437  *
4438  * Sets current sink to the desired output current. This can be set during
4439  * any regulator state. IOW, regulator can be disabled or enabled.
4440  *
4441  * If the regulator is enabled then the current will change to the new value
4442  * immediately otherwise if the regulator is disabled the regulator will
4443  * output at the new current when enabled.
4444  *
4445  * NOTE: Regulator system constraints must be set for this regulator before
4446  * calling this function otherwise this call will fail.
4447  */
4448 int regulator_set_current_limit(struct regulator *regulator,
4449 			       int min_uA, int max_uA)
4450 {
4451 	struct regulator_dev *rdev = regulator->rdev;
4452 	int ret;
4453 
4454 	regulator_lock(rdev);
4455 
4456 	/* sanity check */
4457 	if (!rdev->desc->ops->set_current_limit) {
4458 		ret = -EINVAL;
4459 		goto out;
4460 	}
4461 
4462 	/* constraints check */
4463 	ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
4464 	if (ret < 0)
4465 		goto out;
4466 
4467 	ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
4468 out:
4469 	regulator_unlock(rdev);
4470 	return ret;
4471 }
4472 EXPORT_SYMBOL_GPL(regulator_set_current_limit);
4473 
4474 static int _regulator_get_current_limit_unlocked(struct regulator_dev *rdev)
4475 {
4476 	/* sanity check */
4477 	if (!rdev->desc->ops->get_current_limit)
4478 		return -EINVAL;
4479 
4480 	return rdev->desc->ops->get_current_limit(rdev);
4481 }
4482 
4483 static int _regulator_get_current_limit(struct regulator_dev *rdev)
4484 {
4485 	int ret;
4486 
4487 	regulator_lock(rdev);
4488 	ret = _regulator_get_current_limit_unlocked(rdev);
4489 	regulator_unlock(rdev);
4490 
4491 	return ret;
4492 }
4493 
4494 /**
4495  * regulator_get_current_limit - get regulator output current
4496  * @regulator: regulator source
4497  *
4498  * This returns the current supplied by the specified current sink in uA.
4499  *
4500  * NOTE: If the regulator is disabled it will return the current value. This
4501  * function should not be used to determine regulator state.
4502  */
4503 int regulator_get_current_limit(struct regulator *regulator)
4504 {
4505 	return _regulator_get_current_limit(regulator->rdev);
4506 }
4507 EXPORT_SYMBOL_GPL(regulator_get_current_limit);
4508 
4509 /**
4510  * regulator_set_mode - set regulator operating mode
4511  * @regulator: regulator source
4512  * @mode: operating mode - one of the REGULATOR_MODE constants
4513  *
4514  * Set regulator operating mode to increase regulator efficiency or improve
4515  * regulation performance.
4516  *
4517  * NOTE: Regulator system constraints must be set for this regulator before
4518  * calling this function otherwise this call will fail.
4519  */
4520 int regulator_set_mode(struct regulator *regulator, unsigned int mode)
4521 {
4522 	struct regulator_dev *rdev = regulator->rdev;
4523 	int ret;
4524 	int regulator_curr_mode;
4525 
4526 	regulator_lock(rdev);
4527 
4528 	/* sanity check */
4529 	if (!rdev->desc->ops->set_mode) {
4530 		ret = -EINVAL;
4531 		goto out;
4532 	}
4533 
4534 	/* return if the same mode is requested */
4535 	if (rdev->desc->ops->get_mode) {
4536 		regulator_curr_mode = rdev->desc->ops->get_mode(rdev);
4537 		if (regulator_curr_mode == mode) {
4538 			ret = 0;
4539 			goto out;
4540 		}
4541 	}
4542 
4543 	/* constraints check */
4544 	ret = regulator_mode_constrain(rdev, &mode);
4545 	if (ret < 0)
4546 		goto out;
4547 
4548 	ret = rdev->desc->ops->set_mode(rdev, mode);
4549 out:
4550 	regulator_unlock(rdev);
4551 	return ret;
4552 }
4553 EXPORT_SYMBOL_GPL(regulator_set_mode);
4554 
4555 static unsigned int _regulator_get_mode_unlocked(struct regulator_dev *rdev)
4556 {
4557 	/* sanity check */
4558 	if (!rdev->desc->ops->get_mode)
4559 		return -EINVAL;
4560 
4561 	return rdev->desc->ops->get_mode(rdev);
4562 }
4563 
4564 static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
4565 {
4566 	int ret;
4567 
4568 	regulator_lock(rdev);
4569 	ret = _regulator_get_mode_unlocked(rdev);
4570 	regulator_unlock(rdev);
4571 
4572 	return ret;
4573 }
4574 
4575 /**
4576  * regulator_get_mode - get regulator operating mode
4577  * @regulator: regulator source
4578  *
4579  * Get the current regulator operating mode.
4580  */
4581 unsigned int regulator_get_mode(struct regulator *regulator)
4582 {
4583 	return _regulator_get_mode(regulator->rdev);
4584 }
4585 EXPORT_SYMBOL_GPL(regulator_get_mode);
4586 
4587 static int rdev_get_cached_err_flags(struct regulator_dev *rdev)
4588 {
4589 	int ret = 0;
4590 
4591 	if (rdev->use_cached_err) {
4592 		spin_lock(&rdev->err_lock);
4593 		ret = rdev->cached_err;
4594 		spin_unlock(&rdev->err_lock);
4595 	}
4596 	return ret;
4597 }
4598 
4599 static int _regulator_get_error_flags(struct regulator_dev *rdev,
4600 					unsigned int *flags)
4601 {
4602 	int cached_flags, ret = 0;
4603 
4604 	regulator_lock(rdev);
4605 
4606 	cached_flags = rdev_get_cached_err_flags(rdev);
4607 
4608 	if (rdev->desc->ops->get_error_flags)
4609 		ret = rdev->desc->ops->get_error_flags(rdev, flags);
4610 	else if (!rdev->use_cached_err)
4611 		ret = -EINVAL;
4612 
4613 	*flags |= cached_flags;
4614 
4615 	regulator_unlock(rdev);
4616 
4617 	return ret;
4618 }
4619 
4620 /**
4621  * regulator_get_error_flags - get regulator error information
4622  * @regulator: regulator source
4623  * @flags: pointer to store error flags
4624  *
4625  * Get the current regulator error information.
4626  */
4627 int regulator_get_error_flags(struct regulator *regulator,
4628 				unsigned int *flags)
4629 {
4630 	return _regulator_get_error_flags(regulator->rdev, flags);
4631 }
4632 EXPORT_SYMBOL_GPL(regulator_get_error_flags);
4633 
4634 /**
4635  * regulator_set_load - set regulator load
4636  * @regulator: regulator source
4637  * @uA_load: load current
4638  *
4639  * Notifies the regulator core of a new device load. This is then used by
4640  * DRMS (if enabled by constraints) to set the most efficient regulator
4641  * operating mode for the new regulator loading.
4642  *
4643  * Consumer devices notify their supply regulator of the maximum power
4644  * they will require (can be taken from device datasheet in the power
4645  * consumption tables) when they change operational status and hence power
4646  * state. Examples of operational state changes that can affect power
4647  * consumption are :-
4648  *
4649  *    o Device is opened / closed.
4650  *    o Device I/O is about to begin or has just finished.
4651  *    o Device is idling in between work.
4652  *
4653  * This information is also exported via sysfs to userspace.
4654  *
4655  * DRMS will sum the total requested load on the regulator and change
4656  * to the most efficient operating mode if platform constraints allow.
4657  *
4658  * NOTE: when a regulator consumer requests to have a regulator
4659  * disabled then any load that consumer requested no longer counts
4660  * toward the total requested load.  If the regulator is re-enabled
4661  * then the previously requested load will start counting again.
4662  *
4663  * If a regulator is an always-on regulator then an individual consumer's
4664  * load will still be removed if that consumer is fully disabled.
4665  *
4666  * On error a negative errno is returned.
4667  */
4668 int regulator_set_load(struct regulator *regulator, int uA_load)
4669 {
4670 	struct regulator_dev *rdev = regulator->rdev;
4671 	int old_uA_load;
4672 	int ret = 0;
4673 
4674 	regulator_lock(rdev);
4675 	old_uA_load = regulator->uA_load;
4676 	regulator->uA_load = uA_load;
4677 	if (regulator->enable_count && old_uA_load != uA_load) {
4678 		ret = drms_uA_update(rdev);
4679 		if (ret < 0)
4680 			regulator->uA_load = old_uA_load;
4681 	}
4682 	regulator_unlock(rdev);
4683 
4684 	return ret;
4685 }
4686 EXPORT_SYMBOL_GPL(regulator_set_load);
4687 
4688 /**
4689  * regulator_allow_bypass - allow the regulator to go into bypass mode
4690  *
4691  * @regulator: Regulator to configure
4692  * @enable: enable or disable bypass mode
4693  *
4694  * Allow the regulator to go into bypass mode if all other consumers
4695  * for the regulator also enable bypass mode and the machine
4696  * constraints allow this.  Bypass mode means that the regulator is
4697  * simply passing the input directly to the output with no regulation.
4698  */
4699 int regulator_allow_bypass(struct regulator *regulator, bool enable)
4700 {
4701 	struct regulator_dev *rdev = regulator->rdev;
4702 	const char *name = rdev_get_name(rdev);
4703 	int ret = 0;
4704 
4705 	if (!rdev->desc->ops->set_bypass)
4706 		return 0;
4707 
4708 	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_BYPASS))
4709 		return 0;
4710 
4711 	regulator_lock(rdev);
4712 
4713 	if (enable && !regulator->bypass) {
4714 		rdev->bypass_count++;
4715 
4716 		if (rdev->bypass_count == rdev->open_count) {
4717 			trace_regulator_bypass_enable(name);
4718 
4719 			ret = rdev->desc->ops->set_bypass(rdev, enable);
4720 			if (ret != 0)
4721 				rdev->bypass_count--;
4722 			else
4723 				trace_regulator_bypass_enable_complete(name);
4724 		}
4725 
4726 	} else if (!enable && regulator->bypass) {
4727 		rdev->bypass_count--;
4728 
4729 		if (rdev->bypass_count != rdev->open_count) {
4730 			trace_regulator_bypass_disable(name);
4731 
4732 			ret = rdev->desc->ops->set_bypass(rdev, enable);
4733 			if (ret != 0)
4734 				rdev->bypass_count++;
4735 			else
4736 				trace_regulator_bypass_disable_complete(name);
4737 		}
4738 	}
4739 
4740 	if (ret == 0)
4741 		regulator->bypass = enable;
4742 
4743 	regulator_unlock(rdev);
4744 
4745 	return ret;
4746 }
4747 EXPORT_SYMBOL_GPL(regulator_allow_bypass);
4748 
4749 /**
4750  * regulator_register_notifier - register regulator event notifier
4751  * @regulator: regulator source
4752  * @nb: notifier block
4753  *
4754  * Register notifier block to receive regulator events.
4755  */
4756 int regulator_register_notifier(struct regulator *regulator,
4757 			      struct notifier_block *nb)
4758 {
4759 	return blocking_notifier_chain_register(&regulator->rdev->notifier,
4760 						nb);
4761 }
4762 EXPORT_SYMBOL_GPL(regulator_register_notifier);
4763 
4764 /**
4765  * regulator_unregister_notifier - unregister regulator event notifier
4766  * @regulator: regulator source
4767  * @nb: notifier block
4768  *
4769  * Unregister regulator event notifier block.
4770  */
4771 int regulator_unregister_notifier(struct regulator *regulator,
4772 				struct notifier_block *nb)
4773 {
4774 	return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
4775 						  nb);
4776 }
4777 EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
4778 
4779 /* notify regulator consumers and downstream regulator consumers.
4780  * Note mutex must be held by caller.
4781  */
4782 static int _notifier_call_chain(struct regulator_dev *rdev,
4783 				  unsigned long event, void *data)
4784 {
4785 	/* call rdev chain first */
4786 	return blocking_notifier_call_chain(&rdev->notifier, event, data);
4787 }
4788 
4789 int _regulator_bulk_get(struct device *dev, int num_consumers,
4790 			struct regulator_bulk_data *consumers, enum regulator_get_type get_type)
4791 {
4792 	int i;
4793 	int ret;
4794 
4795 	for (i = 0; i < num_consumers; i++)
4796 		consumers[i].consumer = NULL;
4797 
4798 	for (i = 0; i < num_consumers; i++) {
4799 		consumers[i].consumer = _regulator_get(dev,
4800 						       consumers[i].supply, get_type);
4801 		if (IS_ERR(consumers[i].consumer)) {
4802 			ret = dev_err_probe(dev, PTR_ERR(consumers[i].consumer),
4803 					    "Failed to get supply '%s'",
4804 					    consumers[i].supply);
4805 			consumers[i].consumer = NULL;
4806 			goto err;
4807 		}
4808 
4809 		if (consumers[i].init_load_uA > 0) {
4810 			ret = regulator_set_load(consumers[i].consumer,
4811 						 consumers[i].init_load_uA);
4812 			if (ret) {
4813 				i++;
4814 				goto err;
4815 			}
4816 		}
4817 	}
4818 
4819 	return 0;
4820 
4821 err:
4822 	while (--i >= 0)
4823 		regulator_put(consumers[i].consumer);
4824 
4825 	return ret;
4826 }
4827 
4828 /**
4829  * regulator_bulk_get - get multiple regulator consumers
4830  *
4831  * @dev:           Device to supply
4832  * @num_consumers: Number of consumers to register
4833  * @consumers:     Configuration of consumers; clients are stored here.
4834  *
4835  * @return 0 on success, an errno on failure.
4836  *
4837  * This helper function allows drivers to get several regulator
4838  * consumers in one operation.  If any of the regulators cannot be
4839  * acquired then any regulators that were allocated will be freed
4840  * before returning to the caller.
4841  */
4842 int regulator_bulk_get(struct device *dev, int num_consumers,
4843 		       struct regulator_bulk_data *consumers)
4844 {
4845 	return _regulator_bulk_get(dev, num_consumers, consumers, NORMAL_GET);
4846 }
4847 EXPORT_SYMBOL_GPL(regulator_bulk_get);
4848 
4849 static void regulator_bulk_enable_async(void *data, async_cookie_t cookie)
4850 {
4851 	struct regulator_bulk_data *bulk = data;
4852 
4853 	bulk->ret = regulator_enable(bulk->consumer);
4854 }
4855 
4856 /**
4857  * regulator_bulk_enable - enable multiple regulator consumers
4858  *
4859  * @num_consumers: Number of consumers
4860  * @consumers:     Consumer data; clients are stored here.
4861  * @return         0 on success, an errno on failure
4862  *
4863  * This convenience API allows consumers to enable multiple regulator
4864  * clients in a single API call.  If any consumers cannot be enabled
4865  * then any others that were enabled will be disabled again prior to
4866  * return.
4867  */
4868 int regulator_bulk_enable(int num_consumers,
4869 			  struct regulator_bulk_data *consumers)
4870 {
4871 	ASYNC_DOMAIN_EXCLUSIVE(async_domain);
4872 	int i;
4873 	int ret = 0;
4874 
4875 	for (i = 0; i < num_consumers; i++) {
4876 		async_schedule_domain(regulator_bulk_enable_async,
4877 				      &consumers[i], &async_domain);
4878 	}
4879 
4880 	async_synchronize_full_domain(&async_domain);
4881 
4882 	/* If any consumer failed we need to unwind any that succeeded */
4883 	for (i = 0; i < num_consumers; i++) {
4884 		if (consumers[i].ret != 0) {
4885 			ret = consumers[i].ret;
4886 			goto err;
4887 		}
4888 	}
4889 
4890 	return 0;
4891 
4892 err:
4893 	for (i = 0; i < num_consumers; i++) {
4894 		if (consumers[i].ret < 0)
4895 			pr_err("Failed to enable %s: %pe\n", consumers[i].supply,
4896 			       ERR_PTR(consumers[i].ret));
4897 		else
4898 			regulator_disable(consumers[i].consumer);
4899 	}
4900 
4901 	return ret;
4902 }
4903 EXPORT_SYMBOL_GPL(regulator_bulk_enable);
4904 
4905 /**
4906  * regulator_bulk_disable - disable multiple regulator consumers
4907  *
4908  * @num_consumers: Number of consumers
4909  * @consumers:     Consumer data; clients are stored here.
4910  * @return         0 on success, an errno on failure
4911  *
4912  * This convenience API allows consumers to disable multiple regulator
4913  * clients in a single API call.  If any consumers cannot be disabled
4914  * then any others that were disabled will be enabled again prior to
4915  * return.
4916  */
4917 int regulator_bulk_disable(int num_consumers,
4918 			   struct regulator_bulk_data *consumers)
4919 {
4920 	int i;
4921 	int ret, r;
4922 
4923 	for (i = num_consumers - 1; i >= 0; --i) {
4924 		ret = regulator_disable(consumers[i].consumer);
4925 		if (ret != 0)
4926 			goto err;
4927 	}
4928 
4929 	return 0;
4930 
4931 err:
4932 	pr_err("Failed to disable %s: %pe\n", consumers[i].supply, ERR_PTR(ret));
4933 	for (++i; i < num_consumers; ++i) {
4934 		r = regulator_enable(consumers[i].consumer);
4935 		if (r != 0)
4936 			pr_err("Failed to re-enable %s: %pe\n",
4937 			       consumers[i].supply, ERR_PTR(r));
4938 	}
4939 
4940 	return ret;
4941 }
4942 EXPORT_SYMBOL_GPL(regulator_bulk_disable);
4943 
4944 /**
4945  * regulator_bulk_force_disable - force disable multiple regulator consumers
4946  *
4947  * @num_consumers: Number of consumers
4948  * @consumers:     Consumer data; clients are stored here.
4949  * @return         0 on success, an errno on failure
4950  *
4951  * This convenience API allows consumers to forcibly disable multiple regulator
4952  * clients in a single API call.
4953  * NOTE: This should be used for situations when device damage will
4954  * likely occur if the regulators are not disabled (e.g. over temp).
4955  * Although regulator_force_disable function call for some consumers can
4956  * return error numbers, the function is called for all consumers.
4957  */
4958 int regulator_bulk_force_disable(int num_consumers,
4959 			   struct regulator_bulk_data *consumers)
4960 {
4961 	int i;
4962 	int ret = 0;
4963 
4964 	for (i = 0; i < num_consumers; i++) {
4965 		consumers[i].ret =
4966 			    regulator_force_disable(consumers[i].consumer);
4967 
4968 		/* Store first error for reporting */
4969 		if (consumers[i].ret && !ret)
4970 			ret = consumers[i].ret;
4971 	}
4972 
4973 	return ret;
4974 }
4975 EXPORT_SYMBOL_GPL(regulator_bulk_force_disable);
4976 
4977 /**
4978  * regulator_bulk_free - free multiple regulator consumers
4979  *
4980  * @num_consumers: Number of consumers
4981  * @consumers:     Consumer data; clients are stored here.
4982  *
4983  * This convenience API allows consumers to free multiple regulator
4984  * clients in a single API call.
4985  */
4986 void regulator_bulk_free(int num_consumers,
4987 			 struct regulator_bulk_data *consumers)
4988 {
4989 	int i;
4990 
4991 	for (i = 0; i < num_consumers; i++) {
4992 		regulator_put(consumers[i].consumer);
4993 		consumers[i].consumer = NULL;
4994 	}
4995 }
4996 EXPORT_SYMBOL_GPL(regulator_bulk_free);
4997 
4998 /**
4999  * regulator_notifier_call_chain - call regulator event notifier
5000  * @rdev: regulator source
5001  * @event: notifier block
5002  * @data: callback-specific data.
5003  *
5004  * Called by regulator drivers to notify clients a regulator event has
5005  * occurred.
5006  */
5007 int regulator_notifier_call_chain(struct regulator_dev *rdev,
5008 				  unsigned long event, void *data)
5009 {
5010 	_notifier_call_chain(rdev, event, data);
5011 	return NOTIFY_DONE;
5012 
5013 }
5014 EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
5015 
5016 /**
5017  * regulator_mode_to_status - convert a regulator mode into a status
5018  *
5019  * @mode: Mode to convert
5020  *
5021  * Convert a regulator mode into a status.
5022  */
5023 int regulator_mode_to_status(unsigned int mode)
5024 {
5025 	switch (mode) {
5026 	case REGULATOR_MODE_FAST:
5027 		return REGULATOR_STATUS_FAST;
5028 	case REGULATOR_MODE_NORMAL:
5029 		return REGULATOR_STATUS_NORMAL;
5030 	case REGULATOR_MODE_IDLE:
5031 		return REGULATOR_STATUS_IDLE;
5032 	case REGULATOR_MODE_STANDBY:
5033 		return REGULATOR_STATUS_STANDBY;
5034 	default:
5035 		return REGULATOR_STATUS_UNDEFINED;
5036 	}
5037 }
5038 EXPORT_SYMBOL_GPL(regulator_mode_to_status);
5039 
5040 static struct attribute *regulator_dev_attrs[] = {
5041 	&dev_attr_name.attr,
5042 	&dev_attr_num_users.attr,
5043 	&dev_attr_type.attr,
5044 	&dev_attr_microvolts.attr,
5045 	&dev_attr_microamps.attr,
5046 	&dev_attr_opmode.attr,
5047 	&dev_attr_state.attr,
5048 	&dev_attr_status.attr,
5049 	&dev_attr_bypass.attr,
5050 	&dev_attr_requested_microamps.attr,
5051 	&dev_attr_min_microvolts.attr,
5052 	&dev_attr_max_microvolts.attr,
5053 	&dev_attr_min_microamps.attr,
5054 	&dev_attr_max_microamps.attr,
5055 	&dev_attr_under_voltage.attr,
5056 	&dev_attr_over_current.attr,
5057 	&dev_attr_regulation_out.attr,
5058 	&dev_attr_fail.attr,
5059 	&dev_attr_over_temp.attr,
5060 	&dev_attr_under_voltage_warn.attr,
5061 	&dev_attr_over_current_warn.attr,
5062 	&dev_attr_over_voltage_warn.attr,
5063 	&dev_attr_over_temp_warn.attr,
5064 	&dev_attr_suspend_standby_state.attr,
5065 	&dev_attr_suspend_mem_state.attr,
5066 	&dev_attr_suspend_disk_state.attr,
5067 	&dev_attr_suspend_standby_microvolts.attr,
5068 	&dev_attr_suspend_mem_microvolts.attr,
5069 	&dev_attr_suspend_disk_microvolts.attr,
5070 	&dev_attr_suspend_standby_mode.attr,
5071 	&dev_attr_suspend_mem_mode.attr,
5072 	&dev_attr_suspend_disk_mode.attr,
5073 	NULL
5074 };
5075 
5076 /*
5077  * To avoid cluttering sysfs (and memory) with useless state, only
5078  * create attributes that can be meaningfully displayed.
5079  */
5080 static umode_t regulator_attr_is_visible(struct kobject *kobj,
5081 					 struct attribute *attr, int idx)
5082 {
5083 	struct device *dev = kobj_to_dev(kobj);
5084 	struct regulator_dev *rdev = dev_to_rdev(dev);
5085 	const struct regulator_ops *ops = rdev->desc->ops;
5086 	umode_t mode = attr->mode;
5087 
5088 	/* these three are always present */
5089 	if (attr == &dev_attr_name.attr ||
5090 	    attr == &dev_attr_num_users.attr ||
5091 	    attr == &dev_attr_type.attr)
5092 		return mode;
5093 
5094 	/* some attributes need specific methods to be displayed */
5095 	if (attr == &dev_attr_microvolts.attr) {
5096 		if ((ops->get_voltage && ops->get_voltage(rdev) >= 0) ||
5097 		    (ops->get_voltage_sel && ops->get_voltage_sel(rdev) >= 0) ||
5098 		    (ops->list_voltage && ops->list_voltage(rdev, 0) >= 0) ||
5099 		    (rdev->desc->fixed_uV && rdev->desc->n_voltages == 1))
5100 			return mode;
5101 		return 0;
5102 	}
5103 
5104 	if (attr == &dev_attr_microamps.attr)
5105 		return ops->get_current_limit ? mode : 0;
5106 
5107 	if (attr == &dev_attr_opmode.attr)
5108 		return ops->get_mode ? mode : 0;
5109 
5110 	if (attr == &dev_attr_state.attr)
5111 		return (rdev->ena_pin || ops->is_enabled) ? mode : 0;
5112 
5113 	if (attr == &dev_attr_status.attr)
5114 		return ops->get_status ? mode : 0;
5115 
5116 	if (attr == &dev_attr_bypass.attr)
5117 		return ops->get_bypass ? mode : 0;
5118 
5119 	if (attr == &dev_attr_under_voltage.attr ||
5120 	    attr == &dev_attr_over_current.attr ||
5121 	    attr == &dev_attr_regulation_out.attr ||
5122 	    attr == &dev_attr_fail.attr ||
5123 	    attr == &dev_attr_over_temp.attr ||
5124 	    attr == &dev_attr_under_voltage_warn.attr ||
5125 	    attr == &dev_attr_over_current_warn.attr ||
5126 	    attr == &dev_attr_over_voltage_warn.attr ||
5127 	    attr == &dev_attr_over_temp_warn.attr)
5128 		return ops->get_error_flags ? mode : 0;
5129 
5130 	/* constraints need specific supporting methods */
5131 	if (attr == &dev_attr_min_microvolts.attr ||
5132 	    attr == &dev_attr_max_microvolts.attr)
5133 		return (ops->set_voltage || ops->set_voltage_sel) ? mode : 0;
5134 
5135 	if (attr == &dev_attr_min_microamps.attr ||
5136 	    attr == &dev_attr_max_microamps.attr)
5137 		return ops->set_current_limit ? mode : 0;
5138 
5139 	if (attr == &dev_attr_suspend_standby_state.attr ||
5140 	    attr == &dev_attr_suspend_mem_state.attr ||
5141 	    attr == &dev_attr_suspend_disk_state.attr)
5142 		return mode;
5143 
5144 	if (attr == &dev_attr_suspend_standby_microvolts.attr ||
5145 	    attr == &dev_attr_suspend_mem_microvolts.attr ||
5146 	    attr == &dev_attr_suspend_disk_microvolts.attr)
5147 		return ops->set_suspend_voltage ? mode : 0;
5148 
5149 	if (attr == &dev_attr_suspend_standby_mode.attr ||
5150 	    attr == &dev_attr_suspend_mem_mode.attr ||
5151 	    attr == &dev_attr_suspend_disk_mode.attr)
5152 		return ops->set_suspend_mode ? mode : 0;
5153 
5154 	return mode;
5155 }
5156 
5157 static const struct attribute_group regulator_dev_group = {
5158 	.attrs = regulator_dev_attrs,
5159 	.is_visible = regulator_attr_is_visible,
5160 };
5161 
5162 static const struct attribute_group *regulator_dev_groups[] = {
5163 	&regulator_dev_group,
5164 	NULL
5165 };
5166 
5167 static void regulator_dev_release(struct device *dev)
5168 {
5169 	struct regulator_dev *rdev = dev_get_drvdata(dev);
5170 
5171 	debugfs_remove_recursive(rdev->debugfs);
5172 	kfree(rdev->constraints);
5173 	of_node_put(rdev->dev.of_node);
5174 	kfree(rdev);
5175 }
5176 
5177 static void rdev_init_debugfs(struct regulator_dev *rdev)
5178 {
5179 	struct device *parent = rdev->dev.parent;
5180 	const char *rname = rdev_get_name(rdev);
5181 	char name[NAME_MAX];
5182 
5183 	/* Avoid duplicate debugfs directory names */
5184 	if (parent && rname == rdev->desc->name) {
5185 		snprintf(name, sizeof(name), "%s-%s", dev_name(parent),
5186 			 rname);
5187 		rname = name;
5188 	}
5189 
5190 	rdev->debugfs = debugfs_create_dir(rname, debugfs_root);
5191 	if (!rdev->debugfs) {
5192 		rdev_warn(rdev, "Failed to create debugfs directory\n");
5193 		return;
5194 	}
5195 
5196 	debugfs_create_u32("use_count", 0444, rdev->debugfs,
5197 			   &rdev->use_count);
5198 	debugfs_create_u32("open_count", 0444, rdev->debugfs,
5199 			   &rdev->open_count);
5200 	debugfs_create_u32("bypass_count", 0444, rdev->debugfs,
5201 			   &rdev->bypass_count);
5202 }
5203 
5204 static int regulator_register_resolve_supply(struct device *dev, void *data)
5205 {
5206 	struct regulator_dev *rdev = dev_to_rdev(dev);
5207 
5208 	if (regulator_resolve_supply(rdev))
5209 		rdev_dbg(rdev, "unable to resolve supply\n");
5210 
5211 	return 0;
5212 }
5213 
5214 int regulator_coupler_register(struct regulator_coupler *coupler)
5215 {
5216 	mutex_lock(&regulator_list_mutex);
5217 	list_add_tail(&coupler->list, &regulator_coupler_list);
5218 	mutex_unlock(&regulator_list_mutex);
5219 
5220 	return 0;
5221 }
5222 
5223 static struct regulator_coupler *
5224 regulator_find_coupler(struct regulator_dev *rdev)
5225 {
5226 	struct regulator_coupler *coupler;
5227 	int err;
5228 
5229 	/*
5230 	 * Note that regulators are appended to the list and the generic
5231 	 * coupler is registered first, hence it will be attached at last
5232 	 * if nobody cared.
5233 	 */
5234 	list_for_each_entry_reverse(coupler, &regulator_coupler_list, list) {
5235 		err = coupler->attach_regulator(coupler, rdev);
5236 		if (!err) {
5237 			if (!coupler->balance_voltage &&
5238 			    rdev->coupling_desc.n_coupled > 2)
5239 				goto err_unsupported;
5240 
5241 			return coupler;
5242 		}
5243 
5244 		if (err < 0)
5245 			return ERR_PTR(err);
5246 
5247 		if (err == 1)
5248 			continue;
5249 
5250 		break;
5251 	}
5252 
5253 	return ERR_PTR(-EINVAL);
5254 
5255 err_unsupported:
5256 	if (coupler->detach_regulator)
5257 		coupler->detach_regulator(coupler, rdev);
5258 
5259 	rdev_err(rdev,
5260 		"Voltage balancing for multiple regulator couples is unimplemented\n");
5261 
5262 	return ERR_PTR(-EPERM);
5263 }
5264 
5265 static void regulator_resolve_coupling(struct regulator_dev *rdev)
5266 {
5267 	struct regulator_coupler *coupler = rdev->coupling_desc.coupler;
5268 	struct coupling_desc *c_desc = &rdev->coupling_desc;
5269 	int n_coupled = c_desc->n_coupled;
5270 	struct regulator_dev *c_rdev;
5271 	int i;
5272 
5273 	for (i = 1; i < n_coupled; i++) {
5274 		/* already resolved */
5275 		if (c_desc->coupled_rdevs[i])
5276 			continue;
5277 
5278 		c_rdev = of_parse_coupled_regulator(rdev, i - 1);
5279 
5280 		if (!c_rdev)
5281 			continue;
5282 
5283 		if (c_rdev->coupling_desc.coupler != coupler) {
5284 			rdev_err(rdev, "coupler mismatch with %s\n",
5285 				 rdev_get_name(c_rdev));
5286 			return;
5287 		}
5288 
5289 		c_desc->coupled_rdevs[i] = c_rdev;
5290 		c_desc->n_resolved++;
5291 
5292 		regulator_resolve_coupling(c_rdev);
5293 	}
5294 }
5295 
5296 static void regulator_remove_coupling(struct regulator_dev *rdev)
5297 {
5298 	struct regulator_coupler *coupler = rdev->coupling_desc.coupler;
5299 	struct coupling_desc *__c_desc, *c_desc = &rdev->coupling_desc;
5300 	struct regulator_dev *__c_rdev, *c_rdev;
5301 	unsigned int __n_coupled, n_coupled;
5302 	int i, k;
5303 	int err;
5304 
5305 	n_coupled = c_desc->n_coupled;
5306 
5307 	for (i = 1; i < n_coupled; i++) {
5308 		c_rdev = c_desc->coupled_rdevs[i];
5309 
5310 		if (!c_rdev)
5311 			continue;
5312 
5313 		regulator_lock(c_rdev);
5314 
5315 		__c_desc = &c_rdev->coupling_desc;
5316 		__n_coupled = __c_desc->n_coupled;
5317 
5318 		for (k = 1; k < __n_coupled; k++) {
5319 			__c_rdev = __c_desc->coupled_rdevs[k];
5320 
5321 			if (__c_rdev == rdev) {
5322 				__c_desc->coupled_rdevs[k] = NULL;
5323 				__c_desc->n_resolved--;
5324 				break;
5325 			}
5326 		}
5327 
5328 		regulator_unlock(c_rdev);
5329 
5330 		c_desc->coupled_rdevs[i] = NULL;
5331 		c_desc->n_resolved--;
5332 	}
5333 
5334 	if (coupler && coupler->detach_regulator) {
5335 		err = coupler->detach_regulator(coupler, rdev);
5336 		if (err)
5337 			rdev_err(rdev, "failed to detach from coupler: %pe\n",
5338 				 ERR_PTR(err));
5339 	}
5340 
5341 	kfree(rdev->coupling_desc.coupled_rdevs);
5342 	rdev->coupling_desc.coupled_rdevs = NULL;
5343 }
5344 
5345 static int regulator_init_coupling(struct regulator_dev *rdev)
5346 {
5347 	struct regulator_dev **coupled;
5348 	int err, n_phandles;
5349 
5350 	if (!IS_ENABLED(CONFIG_OF))
5351 		n_phandles = 0;
5352 	else
5353 		n_phandles = of_get_n_coupled(rdev);
5354 
5355 	coupled = kcalloc(n_phandles + 1, sizeof(*coupled), GFP_KERNEL);
5356 	if (!coupled)
5357 		return -ENOMEM;
5358 
5359 	rdev->coupling_desc.coupled_rdevs = coupled;
5360 
5361 	/*
5362 	 * Every regulator should always have coupling descriptor filled with
5363 	 * at least pointer to itself.
5364 	 */
5365 	rdev->coupling_desc.coupled_rdevs[0] = rdev;
5366 	rdev->coupling_desc.n_coupled = n_phandles + 1;
5367 	rdev->coupling_desc.n_resolved++;
5368 
5369 	/* regulator isn't coupled */
5370 	if (n_phandles == 0)
5371 		return 0;
5372 
5373 	if (!of_check_coupling_data(rdev))
5374 		return -EPERM;
5375 
5376 	mutex_lock(&regulator_list_mutex);
5377 	rdev->coupling_desc.coupler = regulator_find_coupler(rdev);
5378 	mutex_unlock(&regulator_list_mutex);
5379 
5380 	if (IS_ERR(rdev->coupling_desc.coupler)) {
5381 		err = PTR_ERR(rdev->coupling_desc.coupler);
5382 		rdev_err(rdev, "failed to get coupler: %pe\n", ERR_PTR(err));
5383 		return err;
5384 	}
5385 
5386 	return 0;
5387 }
5388 
5389 static int generic_coupler_attach(struct regulator_coupler *coupler,
5390 				  struct regulator_dev *rdev)
5391 {
5392 	if (rdev->coupling_desc.n_coupled > 2) {
5393 		rdev_err(rdev,
5394 			 "Voltage balancing for multiple regulator couples is unimplemented\n");
5395 		return -EPERM;
5396 	}
5397 
5398 	if (!rdev->constraints->always_on) {
5399 		rdev_err(rdev,
5400 			 "Coupling of a non always-on regulator is unimplemented\n");
5401 		return -ENOTSUPP;
5402 	}
5403 
5404 	return 0;
5405 }
5406 
5407 static struct regulator_coupler generic_regulator_coupler = {
5408 	.attach_regulator = generic_coupler_attach,
5409 };
5410 
5411 /**
5412  * regulator_register - register regulator
5413  * @dev: the device that drive the regulator
5414  * @regulator_desc: regulator to register
5415  * @cfg: runtime configuration for regulator
5416  *
5417  * Called by regulator drivers to register a regulator.
5418  * Returns a valid pointer to struct regulator_dev on success
5419  * or an ERR_PTR() on error.
5420  */
5421 struct regulator_dev *
5422 regulator_register(struct device *dev,
5423 		   const struct regulator_desc *regulator_desc,
5424 		   const struct regulator_config *cfg)
5425 {
5426 	const struct regulator_init_data *init_data;
5427 	struct regulator_config *config = NULL;
5428 	static atomic_t regulator_no = ATOMIC_INIT(-1);
5429 	struct regulator_dev *rdev;
5430 	bool dangling_cfg_gpiod = false;
5431 	bool dangling_of_gpiod = false;
5432 	int ret, i;
5433 	bool resolved_early = false;
5434 
5435 	if (cfg == NULL)
5436 		return ERR_PTR(-EINVAL);
5437 	if (cfg->ena_gpiod)
5438 		dangling_cfg_gpiod = true;
5439 	if (regulator_desc == NULL) {
5440 		ret = -EINVAL;
5441 		goto rinse;
5442 	}
5443 
5444 	WARN_ON(!dev || !cfg->dev);
5445 
5446 	if (regulator_desc->name == NULL || regulator_desc->ops == NULL) {
5447 		ret = -EINVAL;
5448 		goto rinse;
5449 	}
5450 
5451 	if (regulator_desc->type != REGULATOR_VOLTAGE &&
5452 	    regulator_desc->type != REGULATOR_CURRENT) {
5453 		ret = -EINVAL;
5454 		goto rinse;
5455 	}
5456 
5457 	/* Only one of each should be implemented */
5458 	WARN_ON(regulator_desc->ops->get_voltage &&
5459 		regulator_desc->ops->get_voltage_sel);
5460 	WARN_ON(regulator_desc->ops->set_voltage &&
5461 		regulator_desc->ops->set_voltage_sel);
5462 
5463 	/* If we're using selectors we must implement list_voltage. */
5464 	if (regulator_desc->ops->get_voltage_sel &&
5465 	    !regulator_desc->ops->list_voltage) {
5466 		ret = -EINVAL;
5467 		goto rinse;
5468 	}
5469 	if (regulator_desc->ops->set_voltage_sel &&
5470 	    !regulator_desc->ops->list_voltage) {
5471 		ret = -EINVAL;
5472 		goto rinse;
5473 	}
5474 
5475 	rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
5476 	if (rdev == NULL) {
5477 		ret = -ENOMEM;
5478 		goto rinse;
5479 	}
5480 	device_initialize(&rdev->dev);
5481 	spin_lock_init(&rdev->err_lock);
5482 
5483 	/*
5484 	 * Duplicate the config so the driver could override it after
5485 	 * parsing init data.
5486 	 */
5487 	config = kmemdup(cfg, sizeof(*cfg), GFP_KERNEL);
5488 	if (config == NULL) {
5489 		ret = -ENOMEM;
5490 		goto clean;
5491 	}
5492 
5493 	init_data = regulator_of_get_init_data(dev, regulator_desc, config,
5494 					       &rdev->dev.of_node);
5495 
5496 	/*
5497 	 * Sometimes not all resources are probed already so we need to take
5498 	 * that into account. This happens most the time if the ena_gpiod comes
5499 	 * from a gpio extender or something else.
5500 	 */
5501 	if (PTR_ERR(init_data) == -EPROBE_DEFER) {
5502 		ret = -EPROBE_DEFER;
5503 		goto clean;
5504 	}
5505 
5506 	/*
5507 	 * We need to keep track of any GPIO descriptor coming from the
5508 	 * device tree until we have handled it over to the core. If the
5509 	 * config that was passed in to this function DOES NOT contain
5510 	 * a descriptor, and the config after this call DOES contain
5511 	 * a descriptor, we definitely got one from parsing the device
5512 	 * tree.
5513 	 */
5514 	if (!cfg->ena_gpiod && config->ena_gpiod)
5515 		dangling_of_gpiod = true;
5516 	if (!init_data) {
5517 		init_data = config->init_data;
5518 		rdev->dev.of_node = of_node_get(config->of_node);
5519 	}
5520 
5521 	ww_mutex_init(&rdev->mutex, &regulator_ww_class);
5522 	rdev->reg_data = config->driver_data;
5523 	rdev->owner = regulator_desc->owner;
5524 	rdev->desc = regulator_desc;
5525 	if (config->regmap)
5526 		rdev->regmap = config->regmap;
5527 	else if (dev_get_regmap(dev, NULL))
5528 		rdev->regmap = dev_get_regmap(dev, NULL);
5529 	else if (dev->parent)
5530 		rdev->regmap = dev_get_regmap(dev->parent, NULL);
5531 	INIT_LIST_HEAD(&rdev->consumer_list);
5532 	INIT_LIST_HEAD(&rdev->list);
5533 	BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
5534 	INIT_DELAYED_WORK(&rdev->disable_work, regulator_disable_work);
5535 
5536 	if (init_data && init_data->supply_regulator)
5537 		rdev->supply_name = init_data->supply_regulator;
5538 	else if (regulator_desc->supply_name)
5539 		rdev->supply_name = regulator_desc->supply_name;
5540 
5541 	/* register with sysfs */
5542 	rdev->dev.class = &regulator_class;
5543 	rdev->dev.parent = config->dev;
5544 	dev_set_name(&rdev->dev, "regulator.%lu",
5545 		    (unsigned long) atomic_inc_return(&regulator_no));
5546 	dev_set_drvdata(&rdev->dev, rdev);
5547 
5548 	/* set regulator constraints */
5549 	if (init_data)
5550 		rdev->constraints = kmemdup(&init_data->constraints,
5551 					    sizeof(*rdev->constraints),
5552 					    GFP_KERNEL);
5553 	else
5554 		rdev->constraints = kzalloc(sizeof(*rdev->constraints),
5555 					    GFP_KERNEL);
5556 	if (!rdev->constraints) {
5557 		ret = -ENOMEM;
5558 		goto wash;
5559 	}
5560 
5561 	if ((rdev->supply_name && !rdev->supply) &&
5562 		(rdev->constraints->always_on ||
5563 		 rdev->constraints->boot_on)) {
5564 		ret = regulator_resolve_supply(rdev);
5565 		if (ret)
5566 			rdev_dbg(rdev, "unable to resolve supply early: %pe\n",
5567 					 ERR_PTR(ret));
5568 
5569 		resolved_early = true;
5570 	}
5571 
5572 	/* perform any regulator specific init */
5573 	if (init_data && init_data->regulator_init) {
5574 		ret = init_data->regulator_init(rdev->reg_data);
5575 		if (ret < 0)
5576 			goto wash;
5577 	}
5578 
5579 	if (config->ena_gpiod) {
5580 		ret = regulator_ena_gpio_request(rdev, config);
5581 		if (ret != 0) {
5582 			rdev_err(rdev, "Failed to request enable GPIO: %pe\n",
5583 				 ERR_PTR(ret));
5584 			goto wash;
5585 		}
5586 		/* The regulator core took over the GPIO descriptor */
5587 		dangling_cfg_gpiod = false;
5588 		dangling_of_gpiod = false;
5589 	}
5590 
5591 	ret = set_machine_constraints(rdev);
5592 	if (ret == -EPROBE_DEFER && !resolved_early) {
5593 		/* Regulator might be in bypass mode and so needs its supply
5594 		 * to set the constraints
5595 		 */
5596 		/* FIXME: this currently triggers a chicken-and-egg problem
5597 		 * when creating -SUPPLY symlink in sysfs to a regulator
5598 		 * that is just being created
5599 		 */
5600 		rdev_dbg(rdev, "will resolve supply early: %s\n",
5601 			 rdev->supply_name);
5602 		ret = regulator_resolve_supply(rdev);
5603 		if (!ret)
5604 			ret = set_machine_constraints(rdev);
5605 		else
5606 			rdev_dbg(rdev, "unable to resolve supply early: %pe\n",
5607 				 ERR_PTR(ret));
5608 	}
5609 	if (ret < 0)
5610 		goto wash;
5611 
5612 	ret = regulator_init_coupling(rdev);
5613 	if (ret < 0)
5614 		goto wash;
5615 
5616 	/* add consumers devices */
5617 	if (init_data) {
5618 		for (i = 0; i < init_data->num_consumer_supplies; i++) {
5619 			ret = set_consumer_device_supply(rdev,
5620 				init_data->consumer_supplies[i].dev_name,
5621 				init_data->consumer_supplies[i].supply);
5622 			if (ret < 0) {
5623 				dev_err(dev, "Failed to set supply %s\n",
5624 					init_data->consumer_supplies[i].supply);
5625 				goto unset_supplies;
5626 			}
5627 		}
5628 	}
5629 
5630 	if (!rdev->desc->ops->get_voltage &&
5631 	    !rdev->desc->ops->list_voltage &&
5632 	    !rdev->desc->fixed_uV)
5633 		rdev->is_switch = true;
5634 
5635 	ret = device_add(&rdev->dev);
5636 	if (ret != 0)
5637 		goto unset_supplies;
5638 
5639 	rdev_init_debugfs(rdev);
5640 
5641 	/* try to resolve regulators coupling since a new one was registered */
5642 	mutex_lock(&regulator_list_mutex);
5643 	regulator_resolve_coupling(rdev);
5644 	mutex_unlock(&regulator_list_mutex);
5645 
5646 	/* try to resolve regulators supply since a new one was registered */
5647 	class_for_each_device(&regulator_class, NULL, NULL,
5648 			      regulator_register_resolve_supply);
5649 	kfree(config);
5650 	return rdev;
5651 
5652 unset_supplies:
5653 	mutex_lock(&regulator_list_mutex);
5654 	unset_regulator_supplies(rdev);
5655 	regulator_remove_coupling(rdev);
5656 	mutex_unlock(&regulator_list_mutex);
5657 wash:
5658 	regulator_put(rdev->supply);
5659 	kfree(rdev->coupling_desc.coupled_rdevs);
5660 	mutex_lock(&regulator_list_mutex);
5661 	regulator_ena_gpio_free(rdev);
5662 	mutex_unlock(&regulator_list_mutex);
5663 	put_device(&rdev->dev);
5664 	rdev = NULL;
5665 clean:
5666 	if (dangling_of_gpiod)
5667 		gpiod_put(config->ena_gpiod);
5668 	if (rdev && rdev->dev.of_node)
5669 		of_node_put(rdev->dev.of_node);
5670 	kfree(rdev);
5671 	kfree(config);
5672 rinse:
5673 	if (dangling_cfg_gpiod)
5674 		gpiod_put(cfg->ena_gpiod);
5675 	return ERR_PTR(ret);
5676 }
5677 EXPORT_SYMBOL_GPL(regulator_register);
5678 
5679 /**
5680  * regulator_unregister - unregister regulator
5681  * @rdev: regulator to unregister
5682  *
5683  * Called by regulator drivers to unregister a regulator.
5684  */
5685 void regulator_unregister(struct regulator_dev *rdev)
5686 {
5687 	if (rdev == NULL)
5688 		return;
5689 
5690 	if (rdev->supply) {
5691 		while (rdev->use_count--)
5692 			regulator_disable(rdev->supply);
5693 		regulator_put(rdev->supply);
5694 	}
5695 
5696 	flush_work(&rdev->disable_work.work);
5697 
5698 	mutex_lock(&regulator_list_mutex);
5699 
5700 	WARN_ON(rdev->open_count);
5701 	regulator_remove_coupling(rdev);
5702 	unset_regulator_supplies(rdev);
5703 	list_del(&rdev->list);
5704 	regulator_ena_gpio_free(rdev);
5705 	device_unregister(&rdev->dev);
5706 
5707 	mutex_unlock(&regulator_list_mutex);
5708 }
5709 EXPORT_SYMBOL_GPL(regulator_unregister);
5710 
5711 #ifdef CONFIG_SUSPEND
5712 /**
5713  * regulator_suspend - prepare regulators for system wide suspend
5714  * @dev: ``&struct device`` pointer that is passed to _regulator_suspend()
5715  *
5716  * Configure each regulator with it's suspend operating parameters for state.
5717  */
5718 static int regulator_suspend(struct device *dev)
5719 {
5720 	struct regulator_dev *rdev = dev_to_rdev(dev);
5721 	suspend_state_t state = pm_suspend_target_state;
5722 	int ret;
5723 	const struct regulator_state *rstate;
5724 
5725 	rstate = regulator_get_suspend_state_check(rdev, state);
5726 	if (!rstate)
5727 		return 0;
5728 
5729 	regulator_lock(rdev);
5730 	ret = __suspend_set_state(rdev, rstate);
5731 	regulator_unlock(rdev);
5732 
5733 	return ret;
5734 }
5735 
5736 static int regulator_resume(struct device *dev)
5737 {
5738 	suspend_state_t state = pm_suspend_target_state;
5739 	struct regulator_dev *rdev = dev_to_rdev(dev);
5740 	struct regulator_state *rstate;
5741 	int ret = 0;
5742 
5743 	rstate = regulator_get_suspend_state(rdev, state);
5744 	if (rstate == NULL)
5745 		return 0;
5746 
5747 	/* Avoid grabbing the lock if we don't need to */
5748 	if (!rdev->desc->ops->resume)
5749 		return 0;
5750 
5751 	regulator_lock(rdev);
5752 
5753 	if (rstate->enabled == ENABLE_IN_SUSPEND ||
5754 	    rstate->enabled == DISABLE_IN_SUSPEND)
5755 		ret = rdev->desc->ops->resume(rdev);
5756 
5757 	regulator_unlock(rdev);
5758 
5759 	return ret;
5760 }
5761 #else /* !CONFIG_SUSPEND */
5762 
5763 #define regulator_suspend	NULL
5764 #define regulator_resume	NULL
5765 
5766 #endif /* !CONFIG_SUSPEND */
5767 
5768 #ifdef CONFIG_PM
5769 static const struct dev_pm_ops __maybe_unused regulator_pm_ops = {
5770 	.suspend	= regulator_suspend,
5771 	.resume		= regulator_resume,
5772 };
5773 #endif
5774 
5775 struct class regulator_class = {
5776 	.name = "regulator",
5777 	.dev_release = regulator_dev_release,
5778 	.dev_groups = regulator_dev_groups,
5779 #ifdef CONFIG_PM
5780 	.pm = &regulator_pm_ops,
5781 #endif
5782 };
5783 /**
5784  * regulator_has_full_constraints - the system has fully specified constraints
5785  *
5786  * Calling this function will cause the regulator API to disable all
5787  * regulators which have a zero use count and don't have an always_on
5788  * constraint in a late_initcall.
5789  *
5790  * The intention is that this will become the default behaviour in a
5791  * future kernel release so users are encouraged to use this facility
5792  * now.
5793  */
5794 void regulator_has_full_constraints(void)
5795 {
5796 	has_full_constraints = 1;
5797 }
5798 EXPORT_SYMBOL_GPL(regulator_has_full_constraints);
5799 
5800 /**
5801  * rdev_get_drvdata - get rdev regulator driver data
5802  * @rdev: regulator
5803  *
5804  * Get rdev regulator driver private data. This call can be used in the
5805  * regulator driver context.
5806  */
5807 void *rdev_get_drvdata(struct regulator_dev *rdev)
5808 {
5809 	return rdev->reg_data;
5810 }
5811 EXPORT_SYMBOL_GPL(rdev_get_drvdata);
5812 
5813 /**
5814  * regulator_get_drvdata - get regulator driver data
5815  * @regulator: regulator
5816  *
5817  * Get regulator driver private data. This call can be used in the consumer
5818  * driver context when non API regulator specific functions need to be called.
5819  */
5820 void *regulator_get_drvdata(struct regulator *regulator)
5821 {
5822 	return regulator->rdev->reg_data;
5823 }
5824 EXPORT_SYMBOL_GPL(regulator_get_drvdata);
5825 
5826 /**
5827  * regulator_set_drvdata - set regulator driver data
5828  * @regulator: regulator
5829  * @data: data
5830  */
5831 void regulator_set_drvdata(struct regulator *regulator, void *data)
5832 {
5833 	regulator->rdev->reg_data = data;
5834 }
5835 EXPORT_SYMBOL_GPL(regulator_set_drvdata);
5836 
5837 /**
5838  * rdev_get_id - get regulator ID
5839  * @rdev: regulator
5840  */
5841 int rdev_get_id(struct regulator_dev *rdev)
5842 {
5843 	return rdev->desc->id;
5844 }
5845 EXPORT_SYMBOL_GPL(rdev_get_id);
5846 
5847 struct device *rdev_get_dev(struct regulator_dev *rdev)
5848 {
5849 	return &rdev->dev;
5850 }
5851 EXPORT_SYMBOL_GPL(rdev_get_dev);
5852 
5853 struct regmap *rdev_get_regmap(struct regulator_dev *rdev)
5854 {
5855 	return rdev->regmap;
5856 }
5857 EXPORT_SYMBOL_GPL(rdev_get_regmap);
5858 
5859 void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
5860 {
5861 	return reg_init_data->driver_data;
5862 }
5863 EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
5864 
5865 #ifdef CONFIG_DEBUG_FS
5866 static int supply_map_show(struct seq_file *sf, void *data)
5867 {
5868 	struct regulator_map *map;
5869 
5870 	list_for_each_entry(map, &regulator_map_list, list) {
5871 		seq_printf(sf, "%s -> %s.%s\n",
5872 				rdev_get_name(map->regulator), map->dev_name,
5873 				map->supply);
5874 	}
5875 
5876 	return 0;
5877 }
5878 DEFINE_SHOW_ATTRIBUTE(supply_map);
5879 
5880 struct summary_data {
5881 	struct seq_file *s;
5882 	struct regulator_dev *parent;
5883 	int level;
5884 };
5885 
5886 static void regulator_summary_show_subtree(struct seq_file *s,
5887 					   struct regulator_dev *rdev,
5888 					   int level);
5889 
5890 static int regulator_summary_show_children(struct device *dev, void *data)
5891 {
5892 	struct regulator_dev *rdev = dev_to_rdev(dev);
5893 	struct summary_data *summary_data = data;
5894 
5895 	if (rdev->supply && rdev->supply->rdev == summary_data->parent)
5896 		regulator_summary_show_subtree(summary_data->s, rdev,
5897 					       summary_data->level + 1);
5898 
5899 	return 0;
5900 }
5901 
5902 static void regulator_summary_show_subtree(struct seq_file *s,
5903 					   struct regulator_dev *rdev,
5904 					   int level)
5905 {
5906 	struct regulation_constraints *c;
5907 	struct regulator *consumer;
5908 	struct summary_data summary_data;
5909 	unsigned int opmode;
5910 
5911 	if (!rdev)
5912 		return;
5913 
5914 	opmode = _regulator_get_mode_unlocked(rdev);
5915 	seq_printf(s, "%*s%-*s %3d %4d %6d %7s ",
5916 		   level * 3 + 1, "",
5917 		   30 - level * 3, rdev_get_name(rdev),
5918 		   rdev->use_count, rdev->open_count, rdev->bypass_count,
5919 		   regulator_opmode_to_str(opmode));
5920 
5921 	seq_printf(s, "%5dmV ", regulator_get_voltage_rdev(rdev) / 1000);
5922 	seq_printf(s, "%5dmA ",
5923 		   _regulator_get_current_limit_unlocked(rdev) / 1000);
5924 
5925 	c = rdev->constraints;
5926 	if (c) {
5927 		switch (rdev->desc->type) {
5928 		case REGULATOR_VOLTAGE:
5929 			seq_printf(s, "%5dmV %5dmV ",
5930 				   c->min_uV / 1000, c->max_uV / 1000);
5931 			break;
5932 		case REGULATOR_CURRENT:
5933 			seq_printf(s, "%5dmA %5dmA ",
5934 				   c->min_uA / 1000, c->max_uA / 1000);
5935 			break;
5936 		}
5937 	}
5938 
5939 	seq_puts(s, "\n");
5940 
5941 	list_for_each_entry(consumer, &rdev->consumer_list, list) {
5942 		if (consumer->dev && consumer->dev->class == &regulator_class)
5943 			continue;
5944 
5945 		seq_printf(s, "%*s%-*s ",
5946 			   (level + 1) * 3 + 1, "",
5947 			   30 - (level + 1) * 3,
5948 			   consumer->supply_name ? consumer->supply_name :
5949 			   consumer->dev ? dev_name(consumer->dev) : "deviceless");
5950 
5951 		switch (rdev->desc->type) {
5952 		case REGULATOR_VOLTAGE:
5953 			seq_printf(s, "%3d %33dmA%c%5dmV %5dmV",
5954 				   consumer->enable_count,
5955 				   consumer->uA_load / 1000,
5956 				   consumer->uA_load && !consumer->enable_count ?
5957 				   '*' : ' ',
5958 				   consumer->voltage[PM_SUSPEND_ON].min_uV / 1000,
5959 				   consumer->voltage[PM_SUSPEND_ON].max_uV / 1000);
5960 			break;
5961 		case REGULATOR_CURRENT:
5962 			break;
5963 		}
5964 
5965 		seq_puts(s, "\n");
5966 	}
5967 
5968 	summary_data.s = s;
5969 	summary_data.level = level;
5970 	summary_data.parent = rdev;
5971 
5972 	class_for_each_device(&regulator_class, NULL, &summary_data,
5973 			      regulator_summary_show_children);
5974 }
5975 
5976 struct summary_lock_data {
5977 	struct ww_acquire_ctx *ww_ctx;
5978 	struct regulator_dev **new_contended_rdev;
5979 	struct regulator_dev **old_contended_rdev;
5980 };
5981 
5982 static int regulator_summary_lock_one(struct device *dev, void *data)
5983 {
5984 	struct regulator_dev *rdev = dev_to_rdev(dev);
5985 	struct summary_lock_data *lock_data = data;
5986 	int ret = 0;
5987 
5988 	if (rdev != *lock_data->old_contended_rdev) {
5989 		ret = regulator_lock_nested(rdev, lock_data->ww_ctx);
5990 
5991 		if (ret == -EDEADLK)
5992 			*lock_data->new_contended_rdev = rdev;
5993 		else
5994 			WARN_ON_ONCE(ret);
5995 	} else {
5996 		*lock_data->old_contended_rdev = NULL;
5997 	}
5998 
5999 	return ret;
6000 }
6001 
6002 static int regulator_summary_unlock_one(struct device *dev, void *data)
6003 {
6004 	struct regulator_dev *rdev = dev_to_rdev(dev);
6005 	struct summary_lock_data *lock_data = data;
6006 
6007 	if (lock_data) {
6008 		if (rdev == *lock_data->new_contended_rdev)
6009 			return -EDEADLK;
6010 	}
6011 
6012 	regulator_unlock(rdev);
6013 
6014 	return 0;
6015 }
6016 
6017 static int regulator_summary_lock_all(struct ww_acquire_ctx *ww_ctx,
6018 				      struct regulator_dev **new_contended_rdev,
6019 				      struct regulator_dev **old_contended_rdev)
6020 {
6021 	struct summary_lock_data lock_data;
6022 	int ret;
6023 
6024 	lock_data.ww_ctx = ww_ctx;
6025 	lock_data.new_contended_rdev = new_contended_rdev;
6026 	lock_data.old_contended_rdev = old_contended_rdev;
6027 
6028 	ret = class_for_each_device(&regulator_class, NULL, &lock_data,
6029 				    regulator_summary_lock_one);
6030 	if (ret)
6031 		class_for_each_device(&regulator_class, NULL, &lock_data,
6032 				      regulator_summary_unlock_one);
6033 
6034 	return ret;
6035 }
6036 
6037 static void regulator_summary_lock(struct ww_acquire_ctx *ww_ctx)
6038 {
6039 	struct regulator_dev *new_contended_rdev = NULL;
6040 	struct regulator_dev *old_contended_rdev = NULL;
6041 	int err;
6042 
6043 	mutex_lock(&regulator_list_mutex);
6044 
6045 	ww_acquire_init(ww_ctx, &regulator_ww_class);
6046 
6047 	do {
6048 		if (new_contended_rdev) {
6049 			ww_mutex_lock_slow(&new_contended_rdev->mutex, ww_ctx);
6050 			old_contended_rdev = new_contended_rdev;
6051 			old_contended_rdev->ref_cnt++;
6052 		}
6053 
6054 		err = regulator_summary_lock_all(ww_ctx,
6055 						 &new_contended_rdev,
6056 						 &old_contended_rdev);
6057 
6058 		if (old_contended_rdev)
6059 			regulator_unlock(old_contended_rdev);
6060 
6061 	} while (err == -EDEADLK);
6062 
6063 	ww_acquire_done(ww_ctx);
6064 }
6065 
6066 static void regulator_summary_unlock(struct ww_acquire_ctx *ww_ctx)
6067 {
6068 	class_for_each_device(&regulator_class, NULL, NULL,
6069 			      regulator_summary_unlock_one);
6070 	ww_acquire_fini(ww_ctx);
6071 
6072 	mutex_unlock(&regulator_list_mutex);
6073 }
6074 
6075 static int regulator_summary_show_roots(struct device *dev, void *data)
6076 {
6077 	struct regulator_dev *rdev = dev_to_rdev(dev);
6078 	struct seq_file *s = data;
6079 
6080 	if (!rdev->supply)
6081 		regulator_summary_show_subtree(s, rdev, 0);
6082 
6083 	return 0;
6084 }
6085 
6086 static int regulator_summary_show(struct seq_file *s, void *data)
6087 {
6088 	struct ww_acquire_ctx ww_ctx;
6089 
6090 	seq_puts(s, " regulator                      use open bypass  opmode voltage current     min     max\n");
6091 	seq_puts(s, "---------------------------------------------------------------------------------------\n");
6092 
6093 	regulator_summary_lock(&ww_ctx);
6094 
6095 	class_for_each_device(&regulator_class, NULL, s,
6096 			      regulator_summary_show_roots);
6097 
6098 	regulator_summary_unlock(&ww_ctx);
6099 
6100 	return 0;
6101 }
6102 DEFINE_SHOW_ATTRIBUTE(regulator_summary);
6103 #endif /* CONFIG_DEBUG_FS */
6104 
6105 static int __init regulator_init(void)
6106 {
6107 	int ret;
6108 
6109 	ret = class_register(&regulator_class);
6110 
6111 	debugfs_root = debugfs_create_dir("regulator", NULL);
6112 	if (!debugfs_root)
6113 		pr_warn("regulator: Failed to create debugfs directory\n");
6114 
6115 #ifdef CONFIG_DEBUG_FS
6116 	debugfs_create_file("supply_map", 0444, debugfs_root, NULL,
6117 			    &supply_map_fops);
6118 
6119 	debugfs_create_file("regulator_summary", 0444, debugfs_root,
6120 			    NULL, &regulator_summary_fops);
6121 #endif
6122 	regulator_dummy_init();
6123 
6124 	regulator_coupler_register(&generic_regulator_coupler);
6125 
6126 	return ret;
6127 }
6128 
6129 /* init early to allow our consumers to complete system booting */
6130 core_initcall(regulator_init);
6131 
6132 static int regulator_late_cleanup(struct device *dev, void *data)
6133 {
6134 	struct regulator_dev *rdev = dev_to_rdev(dev);
6135 	struct regulation_constraints *c = rdev->constraints;
6136 	int ret;
6137 
6138 	if (c && c->always_on)
6139 		return 0;
6140 
6141 	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_STATUS))
6142 		return 0;
6143 
6144 	regulator_lock(rdev);
6145 
6146 	if (rdev->use_count)
6147 		goto unlock;
6148 
6149 	/* If reading the status failed, assume that it's off. */
6150 	if (_regulator_is_enabled(rdev) <= 0)
6151 		goto unlock;
6152 
6153 	if (have_full_constraints()) {
6154 		/* We log since this may kill the system if it goes
6155 		 * wrong.
6156 		 */
6157 		rdev_info(rdev, "disabling\n");
6158 		ret = _regulator_do_disable(rdev);
6159 		if (ret != 0)
6160 			rdev_err(rdev, "couldn't disable: %pe\n", ERR_PTR(ret));
6161 	} else {
6162 		/* The intention is that in future we will
6163 		 * assume that full constraints are provided
6164 		 * so warn even if we aren't going to do
6165 		 * anything here.
6166 		 */
6167 		rdev_warn(rdev, "incomplete constraints, leaving on\n");
6168 	}
6169 
6170 unlock:
6171 	regulator_unlock(rdev);
6172 
6173 	return 0;
6174 }
6175 
6176 static void regulator_init_complete_work_function(struct work_struct *work)
6177 {
6178 	/*
6179 	 * Regulators may had failed to resolve their input supplies
6180 	 * when were registered, either because the input supply was
6181 	 * not registered yet or because its parent device was not
6182 	 * bound yet. So attempt to resolve the input supplies for
6183 	 * pending regulators before trying to disable unused ones.
6184 	 */
6185 	class_for_each_device(&regulator_class, NULL, NULL,
6186 			      regulator_register_resolve_supply);
6187 
6188 	/* If we have a full configuration then disable any regulators
6189 	 * we have permission to change the status for and which are
6190 	 * not in use or always_on.  This is effectively the default
6191 	 * for DT and ACPI as they have full constraints.
6192 	 */
6193 	class_for_each_device(&regulator_class, NULL, NULL,
6194 			      regulator_late_cleanup);
6195 }
6196 
6197 static DECLARE_DELAYED_WORK(regulator_init_complete_work,
6198 			    regulator_init_complete_work_function);
6199 
6200 static int __init regulator_init_complete(void)
6201 {
6202 	/*
6203 	 * Since DT doesn't provide an idiomatic mechanism for
6204 	 * enabling full constraints and since it's much more natural
6205 	 * with DT to provide them just assume that a DT enabled
6206 	 * system has full constraints.
6207 	 */
6208 	if (of_have_populated_dt())
6209 		has_full_constraints = true;
6210 
6211 	/*
6212 	 * We punt completion for an arbitrary amount of time since
6213 	 * systems like distros will load many drivers from userspace
6214 	 * so consumers might not always be ready yet, this is
6215 	 * particularly an issue with laptops where this might bounce
6216 	 * the display off then on.  Ideally we'd get a notification
6217 	 * from userspace when this happens but we don't so just wait
6218 	 * a bit and hope we waited long enough.  It'd be better if
6219 	 * we'd only do this on systems that need it, and a kernel
6220 	 * command line option might be useful.
6221 	 */
6222 	schedule_delayed_work(&regulator_init_complete_work,
6223 			      msecs_to_jiffies(30000));
6224 
6225 	return 0;
6226 }
6227 late_initcall_sync(regulator_init_complete);
6228