xref: /openbmc/linux/drivers/regulator/core.c (revision 55eb9a6c)
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 		/* get output voltage */
981 		output_uV = regulator_get_voltage_rdev(rdev);
982 		if (output_uV <= 0) {
983 			rdev_err(rdev, "invalid output voltage found\n");
984 			return -EINVAL;
985 		}
986 
987 		/* get input voltage */
988 		input_uV = 0;
989 		if (rdev->supply)
990 			input_uV = regulator_get_voltage(rdev->supply);
991 		if (input_uV <= 0)
992 			input_uV = rdev->constraints->input_uV;
993 		if (input_uV <= 0) {
994 			rdev_err(rdev, "invalid input voltage found\n");
995 			return -EINVAL;
996 		}
997 
998 		/* now get the optimum mode for our new total regulator load */
999 		mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
1000 							 output_uV, current_uA);
1001 
1002 		/* check the new mode is allowed */
1003 		err = regulator_mode_constrain(rdev, &mode);
1004 		if (err < 0) {
1005 			rdev_err(rdev, "failed to get optimum mode @ %d uA %d -> %d uV: %pe\n",
1006 				 current_uA, input_uV, output_uV, ERR_PTR(err));
1007 			return err;
1008 		}
1009 
1010 		err = rdev->desc->ops->set_mode(rdev, mode);
1011 		if (err < 0)
1012 			rdev_err(rdev, "failed to set optimum mode %x: %pe\n",
1013 				 mode, ERR_PTR(err));
1014 	}
1015 
1016 	return err;
1017 }
1018 
1019 static int __suspend_set_state(struct regulator_dev *rdev,
1020 			       const struct regulator_state *rstate)
1021 {
1022 	int ret = 0;
1023 
1024 	if (rstate->enabled == ENABLE_IN_SUSPEND &&
1025 		rdev->desc->ops->set_suspend_enable)
1026 		ret = rdev->desc->ops->set_suspend_enable(rdev);
1027 	else if (rstate->enabled == DISABLE_IN_SUSPEND &&
1028 		rdev->desc->ops->set_suspend_disable)
1029 		ret = rdev->desc->ops->set_suspend_disable(rdev);
1030 	else /* OK if set_suspend_enable or set_suspend_disable is NULL */
1031 		ret = 0;
1032 
1033 	if (ret < 0) {
1034 		rdev_err(rdev, "failed to enabled/disable: %pe\n", ERR_PTR(ret));
1035 		return ret;
1036 	}
1037 
1038 	if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
1039 		ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
1040 		if (ret < 0) {
1041 			rdev_err(rdev, "failed to set voltage: %pe\n", ERR_PTR(ret));
1042 			return ret;
1043 		}
1044 	}
1045 
1046 	if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
1047 		ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
1048 		if (ret < 0) {
1049 			rdev_err(rdev, "failed to set mode: %pe\n", ERR_PTR(ret));
1050 			return ret;
1051 		}
1052 	}
1053 
1054 	return ret;
1055 }
1056 
1057 static int suspend_set_initial_state(struct regulator_dev *rdev)
1058 {
1059 	const struct regulator_state *rstate;
1060 
1061 	rstate = regulator_get_suspend_state_check(rdev,
1062 			rdev->constraints->initial_state);
1063 	if (!rstate)
1064 		return 0;
1065 
1066 	return __suspend_set_state(rdev, rstate);
1067 }
1068 
1069 #if defined(DEBUG) || defined(CONFIG_DYNAMIC_DEBUG)
1070 static void print_constraints_debug(struct regulator_dev *rdev)
1071 {
1072 	struct regulation_constraints *constraints = rdev->constraints;
1073 	char buf[160] = "";
1074 	size_t len = sizeof(buf) - 1;
1075 	int count = 0;
1076 	int ret;
1077 
1078 	if (constraints->min_uV && constraints->max_uV) {
1079 		if (constraints->min_uV == constraints->max_uV)
1080 			count += scnprintf(buf + count, len - count, "%d mV ",
1081 					   constraints->min_uV / 1000);
1082 		else
1083 			count += scnprintf(buf + count, len - count,
1084 					   "%d <--> %d mV ",
1085 					   constraints->min_uV / 1000,
1086 					   constraints->max_uV / 1000);
1087 	}
1088 
1089 	if (!constraints->min_uV ||
1090 	    constraints->min_uV != constraints->max_uV) {
1091 		ret = regulator_get_voltage_rdev(rdev);
1092 		if (ret > 0)
1093 			count += scnprintf(buf + count, len - count,
1094 					   "at %d mV ", ret / 1000);
1095 	}
1096 
1097 	if (constraints->uV_offset)
1098 		count += scnprintf(buf + count, len - count, "%dmV offset ",
1099 				   constraints->uV_offset / 1000);
1100 
1101 	if (constraints->min_uA && constraints->max_uA) {
1102 		if (constraints->min_uA == constraints->max_uA)
1103 			count += scnprintf(buf + count, len - count, "%d mA ",
1104 					   constraints->min_uA / 1000);
1105 		else
1106 			count += scnprintf(buf + count, len - count,
1107 					   "%d <--> %d mA ",
1108 					   constraints->min_uA / 1000,
1109 					   constraints->max_uA / 1000);
1110 	}
1111 
1112 	if (!constraints->min_uA ||
1113 	    constraints->min_uA != constraints->max_uA) {
1114 		ret = _regulator_get_current_limit(rdev);
1115 		if (ret > 0)
1116 			count += scnprintf(buf + count, len - count,
1117 					   "at %d mA ", ret / 1000);
1118 	}
1119 
1120 	if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
1121 		count += scnprintf(buf + count, len - count, "fast ");
1122 	if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
1123 		count += scnprintf(buf + count, len - count, "normal ");
1124 	if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
1125 		count += scnprintf(buf + count, len - count, "idle ");
1126 	if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
1127 		count += scnprintf(buf + count, len - count, "standby ");
1128 
1129 	if (!count)
1130 		count = scnprintf(buf, len, "no parameters");
1131 	else
1132 		--count;
1133 
1134 	count += scnprintf(buf + count, len - count, ", %s",
1135 		_regulator_is_enabled(rdev) ? "enabled" : "disabled");
1136 
1137 	rdev_dbg(rdev, "%s\n", buf);
1138 }
1139 #else /* !DEBUG && !CONFIG_DYNAMIC_DEBUG */
1140 static inline void print_constraints_debug(struct regulator_dev *rdev) {}
1141 #endif /* !DEBUG && !CONFIG_DYNAMIC_DEBUG */
1142 
1143 static void print_constraints(struct regulator_dev *rdev)
1144 {
1145 	struct regulation_constraints *constraints = rdev->constraints;
1146 
1147 	print_constraints_debug(rdev);
1148 
1149 	if ((constraints->min_uV != constraints->max_uV) &&
1150 	    !regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE))
1151 		rdev_warn(rdev,
1152 			  "Voltage range but no REGULATOR_CHANGE_VOLTAGE\n");
1153 }
1154 
1155 static int machine_constraints_voltage(struct regulator_dev *rdev,
1156 	struct regulation_constraints *constraints)
1157 {
1158 	const struct regulator_ops *ops = rdev->desc->ops;
1159 	int ret;
1160 
1161 	/* do we need to apply the constraint voltage */
1162 	if (rdev->constraints->apply_uV &&
1163 	    rdev->constraints->min_uV && rdev->constraints->max_uV) {
1164 		int target_min, target_max;
1165 		int current_uV = regulator_get_voltage_rdev(rdev);
1166 
1167 		if (current_uV == -ENOTRECOVERABLE) {
1168 			/* This regulator can't be read and must be initialized */
1169 			rdev_info(rdev, "Setting %d-%duV\n",
1170 				  rdev->constraints->min_uV,
1171 				  rdev->constraints->max_uV);
1172 			_regulator_do_set_voltage(rdev,
1173 						  rdev->constraints->min_uV,
1174 						  rdev->constraints->max_uV);
1175 			current_uV = regulator_get_voltage_rdev(rdev);
1176 		}
1177 
1178 		if (current_uV < 0) {
1179 			if (current_uV != -EPROBE_DEFER)
1180 				rdev_err(rdev,
1181 					 "failed to get the current voltage: %pe\n",
1182 					 ERR_PTR(current_uV));
1183 			return current_uV;
1184 		}
1185 
1186 		/*
1187 		 * If we're below the minimum voltage move up to the
1188 		 * minimum voltage, if we're above the maximum voltage
1189 		 * then move down to the maximum.
1190 		 */
1191 		target_min = current_uV;
1192 		target_max = current_uV;
1193 
1194 		if (current_uV < rdev->constraints->min_uV) {
1195 			target_min = rdev->constraints->min_uV;
1196 			target_max = rdev->constraints->min_uV;
1197 		}
1198 
1199 		if (current_uV > rdev->constraints->max_uV) {
1200 			target_min = rdev->constraints->max_uV;
1201 			target_max = rdev->constraints->max_uV;
1202 		}
1203 
1204 		if (target_min != current_uV || target_max != current_uV) {
1205 			rdev_info(rdev, "Bringing %duV into %d-%duV\n",
1206 				  current_uV, target_min, target_max);
1207 			ret = _regulator_do_set_voltage(
1208 				rdev, target_min, target_max);
1209 			if (ret < 0) {
1210 				rdev_err(rdev,
1211 					"failed to apply %d-%duV constraint: %pe\n",
1212 					target_min, target_max, ERR_PTR(ret));
1213 				return ret;
1214 			}
1215 		}
1216 	}
1217 
1218 	/* constrain machine-level voltage specs to fit
1219 	 * the actual range supported by this regulator.
1220 	 */
1221 	if (ops->list_voltage && rdev->desc->n_voltages) {
1222 		int	count = rdev->desc->n_voltages;
1223 		int	i;
1224 		int	min_uV = INT_MAX;
1225 		int	max_uV = INT_MIN;
1226 		int	cmin = constraints->min_uV;
1227 		int	cmax = constraints->max_uV;
1228 
1229 		/* it's safe to autoconfigure fixed-voltage supplies
1230 		 * and the constraints are used by list_voltage.
1231 		 */
1232 		if (count == 1 && !cmin) {
1233 			cmin = 1;
1234 			cmax = INT_MAX;
1235 			constraints->min_uV = cmin;
1236 			constraints->max_uV = cmax;
1237 		}
1238 
1239 		/* voltage constraints are optional */
1240 		if ((cmin == 0) && (cmax == 0))
1241 			return 0;
1242 
1243 		/* else require explicit machine-level constraints */
1244 		if (cmin <= 0 || cmax <= 0 || cmax < cmin) {
1245 			rdev_err(rdev, "invalid voltage constraints\n");
1246 			return -EINVAL;
1247 		}
1248 
1249 		/* no need to loop voltages if range is continuous */
1250 		if (rdev->desc->continuous_voltage_range)
1251 			return 0;
1252 
1253 		/* initial: [cmin..cmax] valid, [min_uV..max_uV] not */
1254 		for (i = 0; i < count; i++) {
1255 			int	value;
1256 
1257 			value = ops->list_voltage(rdev, i);
1258 			if (value <= 0)
1259 				continue;
1260 
1261 			/* maybe adjust [min_uV..max_uV] */
1262 			if (value >= cmin && value < min_uV)
1263 				min_uV = value;
1264 			if (value <= cmax && value > max_uV)
1265 				max_uV = value;
1266 		}
1267 
1268 		/* final: [min_uV..max_uV] valid iff constraints valid */
1269 		if (max_uV < min_uV) {
1270 			rdev_err(rdev,
1271 				 "unsupportable voltage constraints %u-%uuV\n",
1272 				 min_uV, max_uV);
1273 			return -EINVAL;
1274 		}
1275 
1276 		/* use regulator's subset of machine constraints */
1277 		if (constraints->min_uV < min_uV) {
1278 			rdev_dbg(rdev, "override min_uV, %d -> %d\n",
1279 				 constraints->min_uV, min_uV);
1280 			constraints->min_uV = min_uV;
1281 		}
1282 		if (constraints->max_uV > max_uV) {
1283 			rdev_dbg(rdev, "override max_uV, %d -> %d\n",
1284 				 constraints->max_uV, max_uV);
1285 			constraints->max_uV = max_uV;
1286 		}
1287 	}
1288 
1289 	return 0;
1290 }
1291 
1292 static int machine_constraints_current(struct regulator_dev *rdev,
1293 	struct regulation_constraints *constraints)
1294 {
1295 	const struct regulator_ops *ops = rdev->desc->ops;
1296 	int ret;
1297 
1298 	if (!constraints->min_uA && !constraints->max_uA)
1299 		return 0;
1300 
1301 	if (constraints->min_uA > constraints->max_uA) {
1302 		rdev_err(rdev, "Invalid current constraints\n");
1303 		return -EINVAL;
1304 	}
1305 
1306 	if (!ops->set_current_limit || !ops->get_current_limit) {
1307 		rdev_warn(rdev, "Operation of current configuration missing\n");
1308 		return 0;
1309 	}
1310 
1311 	/* Set regulator current in constraints range */
1312 	ret = ops->set_current_limit(rdev, constraints->min_uA,
1313 			constraints->max_uA);
1314 	if (ret < 0) {
1315 		rdev_err(rdev, "Failed to set current constraint, %d\n", ret);
1316 		return ret;
1317 	}
1318 
1319 	return 0;
1320 }
1321 
1322 static int _regulator_do_enable(struct regulator_dev *rdev);
1323 
1324 static int notif_set_limit(struct regulator_dev *rdev,
1325 			   int (*set)(struct regulator_dev *, int, int, bool),
1326 			   int limit, int severity)
1327 {
1328 	bool enable;
1329 
1330 	if (limit == REGULATOR_NOTIF_LIMIT_DISABLE) {
1331 		enable = false;
1332 		limit = 0;
1333 	} else {
1334 		enable = true;
1335 	}
1336 
1337 	if (limit == REGULATOR_NOTIF_LIMIT_ENABLE)
1338 		limit = 0;
1339 
1340 	return set(rdev, limit, severity, enable);
1341 }
1342 
1343 static int handle_notify_limits(struct regulator_dev *rdev,
1344 			int (*set)(struct regulator_dev *, int, int, bool),
1345 			struct notification_limit *limits)
1346 {
1347 	int ret = 0;
1348 
1349 	if (!set)
1350 		return -EOPNOTSUPP;
1351 
1352 	if (limits->prot)
1353 		ret = notif_set_limit(rdev, set, limits->prot,
1354 				      REGULATOR_SEVERITY_PROT);
1355 	if (ret)
1356 		return ret;
1357 
1358 	if (limits->err)
1359 		ret = notif_set_limit(rdev, set, limits->err,
1360 				      REGULATOR_SEVERITY_ERR);
1361 	if (ret)
1362 		return ret;
1363 
1364 	if (limits->warn)
1365 		ret = notif_set_limit(rdev, set, limits->warn,
1366 				      REGULATOR_SEVERITY_WARN);
1367 
1368 	return ret;
1369 }
1370 /**
1371  * set_machine_constraints - sets regulator constraints
1372  * @rdev: regulator source
1373  *
1374  * Allows platform initialisation code to define and constrain
1375  * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
1376  * Constraints *must* be set by platform code in order for some
1377  * regulator operations to proceed i.e. set_voltage, set_current_limit,
1378  * set_mode.
1379  */
1380 static int set_machine_constraints(struct regulator_dev *rdev)
1381 {
1382 	int ret = 0;
1383 	const struct regulator_ops *ops = rdev->desc->ops;
1384 
1385 	ret = machine_constraints_voltage(rdev, rdev->constraints);
1386 	if (ret != 0)
1387 		return ret;
1388 
1389 	ret = machine_constraints_current(rdev, rdev->constraints);
1390 	if (ret != 0)
1391 		return ret;
1392 
1393 	if (rdev->constraints->ilim_uA && ops->set_input_current_limit) {
1394 		ret = ops->set_input_current_limit(rdev,
1395 						   rdev->constraints->ilim_uA);
1396 		if (ret < 0) {
1397 			rdev_err(rdev, "failed to set input limit: %pe\n", ERR_PTR(ret));
1398 			return ret;
1399 		}
1400 	}
1401 
1402 	/* do we need to setup our suspend state */
1403 	if (rdev->constraints->initial_state) {
1404 		ret = suspend_set_initial_state(rdev);
1405 		if (ret < 0) {
1406 			rdev_err(rdev, "failed to set suspend state: %pe\n", ERR_PTR(ret));
1407 			return ret;
1408 		}
1409 	}
1410 
1411 	if (rdev->constraints->initial_mode) {
1412 		if (!ops->set_mode) {
1413 			rdev_err(rdev, "no set_mode operation\n");
1414 			return -EINVAL;
1415 		}
1416 
1417 		ret = ops->set_mode(rdev, rdev->constraints->initial_mode);
1418 		if (ret < 0) {
1419 			rdev_err(rdev, "failed to set initial mode: %pe\n", ERR_PTR(ret));
1420 			return ret;
1421 		}
1422 	} else if (rdev->constraints->system_load) {
1423 		/*
1424 		 * We'll only apply the initial system load if an
1425 		 * initial mode wasn't specified.
1426 		 */
1427 		drms_uA_update(rdev);
1428 	}
1429 
1430 	if ((rdev->constraints->ramp_delay || rdev->constraints->ramp_disable)
1431 		&& ops->set_ramp_delay) {
1432 		ret = ops->set_ramp_delay(rdev, rdev->constraints->ramp_delay);
1433 		if (ret < 0) {
1434 			rdev_err(rdev, "failed to set ramp_delay: %pe\n", ERR_PTR(ret));
1435 			return ret;
1436 		}
1437 	}
1438 
1439 	if (rdev->constraints->pull_down && ops->set_pull_down) {
1440 		ret = ops->set_pull_down(rdev);
1441 		if (ret < 0) {
1442 			rdev_err(rdev, "failed to set pull down: %pe\n", ERR_PTR(ret));
1443 			return ret;
1444 		}
1445 	}
1446 
1447 	if (rdev->constraints->soft_start && ops->set_soft_start) {
1448 		ret = ops->set_soft_start(rdev);
1449 		if (ret < 0) {
1450 			rdev_err(rdev, "failed to set soft start: %pe\n", ERR_PTR(ret));
1451 			return ret;
1452 		}
1453 	}
1454 
1455 	/*
1456 	 * Existing logic does not warn if over_current_protection is given as
1457 	 * a constraint but driver does not support that. I think we should
1458 	 * warn about this type of issues as it is possible someone changes
1459 	 * PMIC on board to another type - and the another PMIC's driver does
1460 	 * not support setting protection. Board composer may happily believe
1461 	 * the DT limits are respected - especially if the new PMIC HW also
1462 	 * supports protection but the driver does not. I won't change the logic
1463 	 * without hearing more experienced opinion on this though.
1464 	 *
1465 	 * If warning is seen as a good idea then we can merge handling the
1466 	 * over-curret protection and detection and get rid of this special
1467 	 * handling.
1468 	 */
1469 	if (rdev->constraints->over_current_protection
1470 		&& ops->set_over_current_protection) {
1471 		int lim = rdev->constraints->over_curr_limits.prot;
1472 
1473 		ret = ops->set_over_current_protection(rdev, lim,
1474 						       REGULATOR_SEVERITY_PROT,
1475 						       true);
1476 		if (ret < 0) {
1477 			rdev_err(rdev, "failed to set over current protection: %pe\n",
1478 				 ERR_PTR(ret));
1479 			return ret;
1480 		}
1481 	}
1482 
1483 	if (rdev->constraints->over_current_detection)
1484 		ret = handle_notify_limits(rdev,
1485 					   ops->set_over_current_protection,
1486 					   &rdev->constraints->over_curr_limits);
1487 	if (ret) {
1488 		if (ret != -EOPNOTSUPP) {
1489 			rdev_err(rdev, "failed to set over current limits: %pe\n",
1490 				 ERR_PTR(ret));
1491 			return ret;
1492 		}
1493 		rdev_warn(rdev,
1494 			  "IC does not support requested over-current limits\n");
1495 	}
1496 
1497 	if (rdev->constraints->over_voltage_detection)
1498 		ret = handle_notify_limits(rdev,
1499 					   ops->set_over_voltage_protection,
1500 					   &rdev->constraints->over_voltage_limits);
1501 	if (ret) {
1502 		if (ret != -EOPNOTSUPP) {
1503 			rdev_err(rdev, "failed to set over voltage limits %pe\n",
1504 				 ERR_PTR(ret));
1505 			return ret;
1506 		}
1507 		rdev_warn(rdev,
1508 			  "IC does not support requested over voltage limits\n");
1509 	}
1510 
1511 	if (rdev->constraints->under_voltage_detection)
1512 		ret = handle_notify_limits(rdev,
1513 					   ops->set_under_voltage_protection,
1514 					   &rdev->constraints->under_voltage_limits);
1515 	if (ret) {
1516 		if (ret != -EOPNOTSUPP) {
1517 			rdev_err(rdev, "failed to set under voltage limits %pe\n",
1518 				 ERR_PTR(ret));
1519 			return ret;
1520 		}
1521 		rdev_warn(rdev,
1522 			  "IC does not support requested under voltage limits\n");
1523 	}
1524 
1525 	if (rdev->constraints->over_temp_detection)
1526 		ret = handle_notify_limits(rdev,
1527 					   ops->set_thermal_protection,
1528 					   &rdev->constraints->temp_limits);
1529 	if (ret) {
1530 		if (ret != -EOPNOTSUPP) {
1531 			rdev_err(rdev, "failed to set temperature limits %pe\n",
1532 				 ERR_PTR(ret));
1533 			return ret;
1534 		}
1535 		rdev_warn(rdev,
1536 			  "IC does not support requested temperature limits\n");
1537 	}
1538 
1539 	if (rdev->constraints->active_discharge && ops->set_active_discharge) {
1540 		bool ad_state = (rdev->constraints->active_discharge ==
1541 			      REGULATOR_ACTIVE_DISCHARGE_ENABLE) ? true : false;
1542 
1543 		ret = ops->set_active_discharge(rdev, ad_state);
1544 		if (ret < 0) {
1545 			rdev_err(rdev, "failed to set active discharge: %pe\n", ERR_PTR(ret));
1546 			return ret;
1547 		}
1548 	}
1549 
1550 	/*
1551 	 * If there is no mechanism for controlling the regulator then
1552 	 * flag it as always_on so we don't end up duplicating checks
1553 	 * for this so much.  Note that we could control the state of
1554 	 * a supply to control the output on a regulator that has no
1555 	 * direct control.
1556 	 */
1557 	if (!rdev->ena_pin && !ops->enable) {
1558 		if (rdev->supply_name && !rdev->supply)
1559 			return -EPROBE_DEFER;
1560 
1561 		if (rdev->supply)
1562 			rdev->constraints->always_on =
1563 				rdev->supply->rdev->constraints->always_on;
1564 		else
1565 			rdev->constraints->always_on = true;
1566 	}
1567 
1568 	/* If the constraints say the regulator should be on at this point
1569 	 * and we have control then make sure it is enabled.
1570 	 */
1571 	if (rdev->constraints->always_on || rdev->constraints->boot_on) {
1572 		/* If we want to enable this regulator, make sure that we know
1573 		 * the supplying regulator.
1574 		 */
1575 		if (rdev->supply_name && !rdev->supply)
1576 			return -EPROBE_DEFER;
1577 
1578 		if (rdev->supply) {
1579 			ret = regulator_enable(rdev->supply);
1580 			if (ret < 0) {
1581 				_regulator_put(rdev->supply);
1582 				rdev->supply = NULL;
1583 				return ret;
1584 			}
1585 		}
1586 
1587 		ret = _regulator_do_enable(rdev);
1588 		if (ret < 0 && ret != -EINVAL) {
1589 			rdev_err(rdev, "failed to enable: %pe\n", ERR_PTR(ret));
1590 			return ret;
1591 		}
1592 
1593 		if (rdev->constraints->always_on)
1594 			rdev->use_count++;
1595 	} else if (rdev->desc->off_on_delay) {
1596 		rdev->last_off = ktime_get();
1597 	}
1598 
1599 	print_constraints(rdev);
1600 	return 0;
1601 }
1602 
1603 /**
1604  * set_supply - set regulator supply regulator
1605  * @rdev: regulator name
1606  * @supply_rdev: supply regulator name
1607  *
1608  * Called by platform initialisation code to set the supply regulator for this
1609  * regulator. This ensures that a regulators supply will also be enabled by the
1610  * core if it's child is enabled.
1611  */
1612 static int set_supply(struct regulator_dev *rdev,
1613 		      struct regulator_dev *supply_rdev)
1614 {
1615 	int err;
1616 
1617 	rdev_dbg(rdev, "supplied by %s\n", rdev_get_name(supply_rdev));
1618 
1619 	if (!try_module_get(supply_rdev->owner))
1620 		return -ENODEV;
1621 
1622 	rdev->supply = create_regulator(supply_rdev, &rdev->dev, "SUPPLY");
1623 	if (rdev->supply == NULL) {
1624 		err = -ENOMEM;
1625 		return err;
1626 	}
1627 	supply_rdev->open_count++;
1628 
1629 	return 0;
1630 }
1631 
1632 /**
1633  * set_consumer_device_supply - Bind a regulator to a symbolic supply
1634  * @rdev:         regulator source
1635  * @consumer_dev_name: dev_name() string for device supply applies to
1636  * @supply:       symbolic name for supply
1637  *
1638  * Allows platform initialisation code to map physical regulator
1639  * sources to symbolic names for supplies for use by devices.  Devices
1640  * should use these symbolic names to request regulators, avoiding the
1641  * need to provide board-specific regulator names as platform data.
1642  */
1643 static int set_consumer_device_supply(struct regulator_dev *rdev,
1644 				      const char *consumer_dev_name,
1645 				      const char *supply)
1646 {
1647 	struct regulator_map *node, *new_node;
1648 	int has_dev;
1649 
1650 	if (supply == NULL)
1651 		return -EINVAL;
1652 
1653 	if (consumer_dev_name != NULL)
1654 		has_dev = 1;
1655 	else
1656 		has_dev = 0;
1657 
1658 	new_node = kzalloc(sizeof(struct regulator_map), GFP_KERNEL);
1659 	if (new_node == NULL)
1660 		return -ENOMEM;
1661 
1662 	new_node->regulator = rdev;
1663 	new_node->supply = supply;
1664 
1665 	if (has_dev) {
1666 		new_node->dev_name = kstrdup(consumer_dev_name, GFP_KERNEL);
1667 		if (new_node->dev_name == NULL) {
1668 			kfree(new_node);
1669 			return -ENOMEM;
1670 		}
1671 	}
1672 
1673 	mutex_lock(&regulator_list_mutex);
1674 	list_for_each_entry(node, &regulator_map_list, list) {
1675 		if (node->dev_name && consumer_dev_name) {
1676 			if (strcmp(node->dev_name, consumer_dev_name) != 0)
1677 				continue;
1678 		} else if (node->dev_name || consumer_dev_name) {
1679 			continue;
1680 		}
1681 
1682 		if (strcmp(node->supply, supply) != 0)
1683 			continue;
1684 
1685 		pr_debug("%s: %s/%s is '%s' supply; fail %s/%s\n",
1686 			 consumer_dev_name,
1687 			 dev_name(&node->regulator->dev),
1688 			 node->regulator->desc->name,
1689 			 supply,
1690 			 dev_name(&rdev->dev), rdev_get_name(rdev));
1691 		goto fail;
1692 	}
1693 
1694 	list_add(&new_node->list, &regulator_map_list);
1695 	mutex_unlock(&regulator_list_mutex);
1696 
1697 	return 0;
1698 
1699 fail:
1700 	mutex_unlock(&regulator_list_mutex);
1701 	kfree(new_node->dev_name);
1702 	kfree(new_node);
1703 	return -EBUSY;
1704 }
1705 
1706 static void unset_regulator_supplies(struct regulator_dev *rdev)
1707 {
1708 	struct regulator_map *node, *n;
1709 
1710 	list_for_each_entry_safe(node, n, &regulator_map_list, list) {
1711 		if (rdev == node->regulator) {
1712 			list_del(&node->list);
1713 			kfree(node->dev_name);
1714 			kfree(node);
1715 		}
1716 	}
1717 }
1718 
1719 #ifdef CONFIG_DEBUG_FS
1720 static ssize_t constraint_flags_read_file(struct file *file,
1721 					  char __user *user_buf,
1722 					  size_t count, loff_t *ppos)
1723 {
1724 	const struct regulator *regulator = file->private_data;
1725 	const struct regulation_constraints *c = regulator->rdev->constraints;
1726 	char *buf;
1727 	ssize_t ret;
1728 
1729 	if (!c)
1730 		return 0;
1731 
1732 	buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
1733 	if (!buf)
1734 		return -ENOMEM;
1735 
1736 	ret = snprintf(buf, PAGE_SIZE,
1737 			"always_on: %u\n"
1738 			"boot_on: %u\n"
1739 			"apply_uV: %u\n"
1740 			"ramp_disable: %u\n"
1741 			"soft_start: %u\n"
1742 			"pull_down: %u\n"
1743 			"over_current_protection: %u\n",
1744 			c->always_on,
1745 			c->boot_on,
1746 			c->apply_uV,
1747 			c->ramp_disable,
1748 			c->soft_start,
1749 			c->pull_down,
1750 			c->over_current_protection);
1751 
1752 	ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
1753 	kfree(buf);
1754 
1755 	return ret;
1756 }
1757 
1758 #endif
1759 
1760 static const struct file_operations constraint_flags_fops = {
1761 #ifdef CONFIG_DEBUG_FS
1762 	.open = simple_open,
1763 	.read = constraint_flags_read_file,
1764 	.llseek = default_llseek,
1765 #endif
1766 };
1767 
1768 #define REG_STR_SIZE	64
1769 
1770 static struct regulator *create_regulator(struct regulator_dev *rdev,
1771 					  struct device *dev,
1772 					  const char *supply_name)
1773 {
1774 	struct regulator *regulator;
1775 	int err = 0;
1776 
1777 	if (dev) {
1778 		char buf[REG_STR_SIZE];
1779 		int size;
1780 
1781 		size = snprintf(buf, REG_STR_SIZE, "%s-%s",
1782 				dev->kobj.name, supply_name);
1783 		if (size >= REG_STR_SIZE)
1784 			return NULL;
1785 
1786 		supply_name = kstrdup(buf, GFP_KERNEL);
1787 		if (supply_name == NULL)
1788 			return NULL;
1789 	} else {
1790 		supply_name = kstrdup_const(supply_name, GFP_KERNEL);
1791 		if (supply_name == NULL)
1792 			return NULL;
1793 	}
1794 
1795 	regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
1796 	if (regulator == NULL) {
1797 		kfree(supply_name);
1798 		return NULL;
1799 	}
1800 
1801 	regulator->rdev = rdev;
1802 	regulator->supply_name = supply_name;
1803 
1804 	regulator_lock(rdev);
1805 	list_add(&regulator->list, &rdev->consumer_list);
1806 	regulator_unlock(rdev);
1807 
1808 	if (dev) {
1809 		regulator->dev = dev;
1810 
1811 		/* Add a link to the device sysfs entry */
1812 		err = sysfs_create_link_nowarn(&rdev->dev.kobj, &dev->kobj,
1813 					       supply_name);
1814 		if (err) {
1815 			rdev_dbg(rdev, "could not add device link %s: %pe\n",
1816 				  dev->kobj.name, ERR_PTR(err));
1817 			/* non-fatal */
1818 		}
1819 	}
1820 
1821 	if (err != -EEXIST)
1822 		regulator->debugfs = debugfs_create_dir(supply_name, rdev->debugfs);
1823 	if (!regulator->debugfs) {
1824 		rdev_dbg(rdev, "Failed to create debugfs directory\n");
1825 	} else {
1826 		debugfs_create_u32("uA_load", 0444, regulator->debugfs,
1827 				   &regulator->uA_load);
1828 		debugfs_create_u32("min_uV", 0444, regulator->debugfs,
1829 				   &regulator->voltage[PM_SUSPEND_ON].min_uV);
1830 		debugfs_create_u32("max_uV", 0444, regulator->debugfs,
1831 				   &regulator->voltage[PM_SUSPEND_ON].max_uV);
1832 		debugfs_create_file("constraint_flags", 0444,
1833 				    regulator->debugfs, regulator,
1834 				    &constraint_flags_fops);
1835 	}
1836 
1837 	/*
1838 	 * Check now if the regulator is an always on regulator - if
1839 	 * it is then we don't need to do nearly so much work for
1840 	 * enable/disable calls.
1841 	 */
1842 	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_STATUS) &&
1843 	    _regulator_is_enabled(rdev))
1844 		regulator->always_on = true;
1845 
1846 	return regulator;
1847 }
1848 
1849 static int _regulator_get_enable_time(struct regulator_dev *rdev)
1850 {
1851 	if (rdev->constraints && rdev->constraints->enable_time)
1852 		return rdev->constraints->enable_time;
1853 	if (rdev->desc->ops->enable_time)
1854 		return rdev->desc->ops->enable_time(rdev);
1855 	return rdev->desc->enable_time;
1856 }
1857 
1858 static struct regulator_supply_alias *regulator_find_supply_alias(
1859 		struct device *dev, const char *supply)
1860 {
1861 	struct regulator_supply_alias *map;
1862 
1863 	list_for_each_entry(map, &regulator_supply_alias_list, list)
1864 		if (map->src_dev == dev && strcmp(map->src_supply, supply) == 0)
1865 			return map;
1866 
1867 	return NULL;
1868 }
1869 
1870 static void regulator_supply_alias(struct device **dev, const char **supply)
1871 {
1872 	struct regulator_supply_alias *map;
1873 
1874 	map = regulator_find_supply_alias(*dev, *supply);
1875 	if (map) {
1876 		dev_dbg(*dev, "Mapping supply %s to %s,%s\n",
1877 				*supply, map->alias_supply,
1878 				dev_name(map->alias_dev));
1879 		*dev = map->alias_dev;
1880 		*supply = map->alias_supply;
1881 	}
1882 }
1883 
1884 static int regulator_match(struct device *dev, const void *data)
1885 {
1886 	struct regulator_dev *r = dev_to_rdev(dev);
1887 
1888 	return strcmp(rdev_get_name(r), data) == 0;
1889 }
1890 
1891 static struct regulator_dev *regulator_lookup_by_name(const char *name)
1892 {
1893 	struct device *dev;
1894 
1895 	dev = class_find_device(&regulator_class, NULL, name, regulator_match);
1896 
1897 	return dev ? dev_to_rdev(dev) : NULL;
1898 }
1899 
1900 /**
1901  * regulator_dev_lookup - lookup a regulator device.
1902  * @dev: device for regulator "consumer".
1903  * @supply: Supply name or regulator ID.
1904  *
1905  * If successful, returns a struct regulator_dev that corresponds to the name
1906  * @supply and with the embedded struct device refcount incremented by one.
1907  * The refcount must be dropped by calling put_device().
1908  * On failure one of the following ERR-PTR-encoded values is returned:
1909  * -ENODEV if lookup fails permanently, -EPROBE_DEFER if lookup could succeed
1910  * in the future.
1911  */
1912 static struct regulator_dev *regulator_dev_lookup(struct device *dev,
1913 						  const char *supply)
1914 {
1915 	struct regulator_dev *r = NULL;
1916 	struct device_node *node;
1917 	struct regulator_map *map;
1918 	const char *devname = NULL;
1919 
1920 	regulator_supply_alias(&dev, &supply);
1921 
1922 	/* first do a dt based lookup */
1923 	if (dev && dev->of_node) {
1924 		node = of_get_regulator(dev, supply);
1925 		if (node) {
1926 			r = of_find_regulator_by_node(node);
1927 			if (r)
1928 				return r;
1929 
1930 			/*
1931 			 * We have a node, but there is no device.
1932 			 * assume it has not registered yet.
1933 			 */
1934 			return ERR_PTR(-EPROBE_DEFER);
1935 		}
1936 	}
1937 
1938 	/* if not found, try doing it non-dt way */
1939 	if (dev)
1940 		devname = dev_name(dev);
1941 
1942 	mutex_lock(&regulator_list_mutex);
1943 	list_for_each_entry(map, &regulator_map_list, list) {
1944 		/* If the mapping has a device set up it must match */
1945 		if (map->dev_name &&
1946 		    (!devname || strcmp(map->dev_name, devname)))
1947 			continue;
1948 
1949 		if (strcmp(map->supply, supply) == 0 &&
1950 		    get_device(&map->regulator->dev)) {
1951 			r = map->regulator;
1952 			break;
1953 		}
1954 	}
1955 	mutex_unlock(&regulator_list_mutex);
1956 
1957 	if (r)
1958 		return r;
1959 
1960 	r = regulator_lookup_by_name(supply);
1961 	if (r)
1962 		return r;
1963 
1964 	return ERR_PTR(-ENODEV);
1965 }
1966 
1967 static int regulator_resolve_supply(struct regulator_dev *rdev)
1968 {
1969 	struct regulator_dev *r;
1970 	struct device *dev = rdev->dev.parent;
1971 	int ret = 0;
1972 
1973 	/* No supply to resolve? */
1974 	if (!rdev->supply_name)
1975 		return 0;
1976 
1977 	/* Supply already resolved? (fast-path without locking contention) */
1978 	if (rdev->supply)
1979 		return 0;
1980 
1981 	r = regulator_dev_lookup(dev, rdev->supply_name);
1982 	if (IS_ERR(r)) {
1983 		ret = PTR_ERR(r);
1984 
1985 		/* Did the lookup explicitly defer for us? */
1986 		if (ret == -EPROBE_DEFER)
1987 			goto out;
1988 
1989 		if (have_full_constraints()) {
1990 			r = dummy_regulator_rdev;
1991 			get_device(&r->dev);
1992 		} else {
1993 			dev_err(dev, "Failed to resolve %s-supply for %s\n",
1994 				rdev->supply_name, rdev->desc->name);
1995 			ret = -EPROBE_DEFER;
1996 			goto out;
1997 		}
1998 	}
1999 
2000 	if (r == rdev) {
2001 		dev_err(dev, "Supply for %s (%s) resolved to itself\n",
2002 			rdev->desc->name, rdev->supply_name);
2003 		if (!have_full_constraints()) {
2004 			ret = -EINVAL;
2005 			goto out;
2006 		}
2007 		r = dummy_regulator_rdev;
2008 		get_device(&r->dev);
2009 	}
2010 
2011 	/*
2012 	 * If the supply's parent device is not the same as the
2013 	 * regulator's parent device, then ensure the parent device
2014 	 * is bound before we resolve the supply, in case the parent
2015 	 * device get probe deferred and unregisters the supply.
2016 	 */
2017 	if (r->dev.parent && r->dev.parent != rdev->dev.parent) {
2018 		if (!device_is_bound(r->dev.parent)) {
2019 			put_device(&r->dev);
2020 			ret = -EPROBE_DEFER;
2021 			goto out;
2022 		}
2023 	}
2024 
2025 	/* Recursively resolve the supply of the supply */
2026 	ret = regulator_resolve_supply(r);
2027 	if (ret < 0) {
2028 		put_device(&r->dev);
2029 		goto out;
2030 	}
2031 
2032 	/*
2033 	 * Recheck rdev->supply with rdev->mutex lock held to avoid a race
2034 	 * between rdev->supply null check and setting rdev->supply in
2035 	 * set_supply() from concurrent tasks.
2036 	 */
2037 	regulator_lock(rdev);
2038 
2039 	/* Supply just resolved by a concurrent task? */
2040 	if (rdev->supply) {
2041 		regulator_unlock(rdev);
2042 		put_device(&r->dev);
2043 		goto out;
2044 	}
2045 
2046 	ret = set_supply(rdev, r);
2047 	if (ret < 0) {
2048 		regulator_unlock(rdev);
2049 		put_device(&r->dev);
2050 		goto out;
2051 	}
2052 
2053 	regulator_unlock(rdev);
2054 
2055 	/*
2056 	 * In set_machine_constraints() we may have turned this regulator on
2057 	 * but we couldn't propagate to the supply if it hadn't been resolved
2058 	 * yet.  Do it now.
2059 	 */
2060 	if (rdev->use_count) {
2061 		ret = regulator_enable(rdev->supply);
2062 		if (ret < 0) {
2063 			_regulator_put(rdev->supply);
2064 			rdev->supply = NULL;
2065 			goto out;
2066 		}
2067 	}
2068 
2069 out:
2070 	return ret;
2071 }
2072 
2073 /* Internal regulator request function */
2074 struct regulator *_regulator_get(struct device *dev, const char *id,
2075 				 enum regulator_get_type get_type)
2076 {
2077 	struct regulator_dev *rdev;
2078 	struct regulator *regulator;
2079 	struct device_link *link;
2080 	int ret;
2081 
2082 	if (get_type >= MAX_GET_TYPE) {
2083 		dev_err(dev, "invalid type %d in %s\n", get_type, __func__);
2084 		return ERR_PTR(-EINVAL);
2085 	}
2086 
2087 	if (id == NULL) {
2088 		pr_err("get() with no identifier\n");
2089 		return ERR_PTR(-EINVAL);
2090 	}
2091 
2092 	rdev = regulator_dev_lookup(dev, id);
2093 	if (IS_ERR(rdev)) {
2094 		ret = PTR_ERR(rdev);
2095 
2096 		/*
2097 		 * If regulator_dev_lookup() fails with error other
2098 		 * than -ENODEV our job here is done, we simply return it.
2099 		 */
2100 		if (ret != -ENODEV)
2101 			return ERR_PTR(ret);
2102 
2103 		if (!have_full_constraints()) {
2104 			dev_warn(dev,
2105 				 "incomplete constraints, dummy supplies not allowed\n");
2106 			return ERR_PTR(-ENODEV);
2107 		}
2108 
2109 		switch (get_type) {
2110 		case NORMAL_GET:
2111 			/*
2112 			 * Assume that a regulator is physically present and
2113 			 * enabled, even if it isn't hooked up, and just
2114 			 * provide a dummy.
2115 			 */
2116 			dev_warn(dev, "supply %s not found, using dummy regulator\n", id);
2117 			rdev = dummy_regulator_rdev;
2118 			get_device(&rdev->dev);
2119 			break;
2120 
2121 		case EXCLUSIVE_GET:
2122 			dev_warn(dev,
2123 				 "dummy supplies not allowed for exclusive requests\n");
2124 			fallthrough;
2125 
2126 		default:
2127 			return ERR_PTR(-ENODEV);
2128 		}
2129 	}
2130 
2131 	if (rdev->exclusive) {
2132 		regulator = ERR_PTR(-EPERM);
2133 		put_device(&rdev->dev);
2134 		return regulator;
2135 	}
2136 
2137 	if (get_type == EXCLUSIVE_GET && rdev->open_count) {
2138 		regulator = ERR_PTR(-EBUSY);
2139 		put_device(&rdev->dev);
2140 		return regulator;
2141 	}
2142 
2143 	mutex_lock(&regulator_list_mutex);
2144 	ret = (rdev->coupling_desc.n_resolved != rdev->coupling_desc.n_coupled);
2145 	mutex_unlock(&regulator_list_mutex);
2146 
2147 	if (ret != 0) {
2148 		regulator = ERR_PTR(-EPROBE_DEFER);
2149 		put_device(&rdev->dev);
2150 		return regulator;
2151 	}
2152 
2153 	ret = regulator_resolve_supply(rdev);
2154 	if (ret < 0) {
2155 		regulator = ERR_PTR(ret);
2156 		put_device(&rdev->dev);
2157 		return regulator;
2158 	}
2159 
2160 	if (!try_module_get(rdev->owner)) {
2161 		regulator = ERR_PTR(-EPROBE_DEFER);
2162 		put_device(&rdev->dev);
2163 		return regulator;
2164 	}
2165 
2166 	regulator = create_regulator(rdev, dev, id);
2167 	if (regulator == NULL) {
2168 		regulator = ERR_PTR(-ENOMEM);
2169 		module_put(rdev->owner);
2170 		put_device(&rdev->dev);
2171 		return regulator;
2172 	}
2173 
2174 	rdev->open_count++;
2175 	if (get_type == EXCLUSIVE_GET) {
2176 		rdev->exclusive = 1;
2177 
2178 		ret = _regulator_is_enabled(rdev);
2179 		if (ret > 0) {
2180 			rdev->use_count = 1;
2181 			regulator->enable_count = 1;
2182 		} else {
2183 			rdev->use_count = 0;
2184 			regulator->enable_count = 0;
2185 		}
2186 	}
2187 
2188 	link = device_link_add(dev, &rdev->dev, DL_FLAG_STATELESS);
2189 	if (!IS_ERR_OR_NULL(link))
2190 		regulator->device_link = true;
2191 
2192 	return regulator;
2193 }
2194 
2195 /**
2196  * regulator_get - lookup and obtain a reference to a regulator.
2197  * @dev: device for regulator "consumer"
2198  * @id: Supply name or regulator ID.
2199  *
2200  * Returns a struct regulator corresponding to the regulator producer,
2201  * or IS_ERR() condition containing errno.
2202  *
2203  * Use of supply names configured via set_consumer_device_supply() is
2204  * strongly encouraged.  It is recommended that the supply name used
2205  * should match the name used for the supply and/or the relevant
2206  * device pins in the datasheet.
2207  */
2208 struct regulator *regulator_get(struct device *dev, const char *id)
2209 {
2210 	return _regulator_get(dev, id, NORMAL_GET);
2211 }
2212 EXPORT_SYMBOL_GPL(regulator_get);
2213 
2214 /**
2215  * regulator_get_exclusive - obtain exclusive access to a regulator.
2216  * @dev: device for regulator "consumer"
2217  * @id: Supply name or regulator ID.
2218  *
2219  * Returns a struct regulator corresponding to the regulator producer,
2220  * or IS_ERR() condition containing errno.  Other consumers will be
2221  * unable to obtain this regulator while this reference is held and the
2222  * use count for the regulator will be initialised to reflect the current
2223  * state of the regulator.
2224  *
2225  * This is intended for use by consumers which cannot tolerate shared
2226  * use of the regulator such as those which need to force the
2227  * regulator off for correct operation of the hardware they are
2228  * controlling.
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_exclusive(struct device *dev, const char *id)
2236 {
2237 	return _regulator_get(dev, id, EXCLUSIVE_GET);
2238 }
2239 EXPORT_SYMBOL_GPL(regulator_get_exclusive);
2240 
2241 /**
2242  * regulator_get_optional - obtain optional 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.
2248  *
2249  * This is intended for use by consumers for devices which can have
2250  * some supplies unconnected in normal use, such as some MMC devices.
2251  * It can allow the regulator core to provide stub supplies for other
2252  * supplies requested using normal regulator_get() calls without
2253  * disrupting the operation of drivers that can handle absent
2254  * supplies.
2255  *
2256  * Use of supply names configured via set_consumer_device_supply() is
2257  * strongly encouraged.  It is recommended that the supply name used
2258  * should match the name used for the supply and/or the relevant
2259  * device pins in the datasheet.
2260  */
2261 struct regulator *regulator_get_optional(struct device *dev, const char *id)
2262 {
2263 	return _regulator_get(dev, id, OPTIONAL_GET);
2264 }
2265 EXPORT_SYMBOL_GPL(regulator_get_optional);
2266 
2267 static void destroy_regulator(struct regulator *regulator)
2268 {
2269 	struct regulator_dev *rdev = regulator->rdev;
2270 
2271 	debugfs_remove_recursive(regulator->debugfs);
2272 
2273 	if (regulator->dev) {
2274 		if (regulator->device_link)
2275 			device_link_remove(regulator->dev, &rdev->dev);
2276 
2277 		/* remove any sysfs entries */
2278 		sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
2279 	}
2280 
2281 	regulator_lock(rdev);
2282 	list_del(&regulator->list);
2283 
2284 	rdev->open_count--;
2285 	rdev->exclusive = 0;
2286 	regulator_unlock(rdev);
2287 
2288 	kfree_const(regulator->supply_name);
2289 	kfree(regulator);
2290 }
2291 
2292 /* regulator_list_mutex lock held by regulator_put() */
2293 static void _regulator_put(struct regulator *regulator)
2294 {
2295 	struct regulator_dev *rdev;
2296 
2297 	if (IS_ERR_OR_NULL(regulator))
2298 		return;
2299 
2300 	lockdep_assert_held_once(&regulator_list_mutex);
2301 
2302 	/* Docs say you must disable before calling regulator_put() */
2303 	WARN_ON(regulator->enable_count);
2304 
2305 	rdev = regulator->rdev;
2306 
2307 	destroy_regulator(regulator);
2308 
2309 	module_put(rdev->owner);
2310 	put_device(&rdev->dev);
2311 }
2312 
2313 /**
2314  * regulator_put - "free" the regulator source
2315  * @regulator: regulator source
2316  *
2317  * Note: drivers must ensure that all regulator_enable calls made on this
2318  * regulator source are balanced by regulator_disable calls prior to calling
2319  * this function.
2320  */
2321 void regulator_put(struct regulator *regulator)
2322 {
2323 	mutex_lock(&regulator_list_mutex);
2324 	_regulator_put(regulator);
2325 	mutex_unlock(&regulator_list_mutex);
2326 }
2327 EXPORT_SYMBOL_GPL(regulator_put);
2328 
2329 /**
2330  * regulator_register_supply_alias - Provide device alias for supply lookup
2331  *
2332  * @dev: device that will be given as the regulator "consumer"
2333  * @id: Supply name or regulator ID
2334  * @alias_dev: device that should be used to lookup the supply
2335  * @alias_id: Supply name or regulator ID that should be used to lookup the
2336  * supply
2337  *
2338  * All lookups for id on dev will instead be conducted for alias_id on
2339  * alias_dev.
2340  */
2341 int regulator_register_supply_alias(struct device *dev, const char *id,
2342 				    struct device *alias_dev,
2343 				    const char *alias_id)
2344 {
2345 	struct regulator_supply_alias *map;
2346 
2347 	map = regulator_find_supply_alias(dev, id);
2348 	if (map)
2349 		return -EEXIST;
2350 
2351 	map = kzalloc(sizeof(struct regulator_supply_alias), GFP_KERNEL);
2352 	if (!map)
2353 		return -ENOMEM;
2354 
2355 	map->src_dev = dev;
2356 	map->src_supply = id;
2357 	map->alias_dev = alias_dev;
2358 	map->alias_supply = alias_id;
2359 
2360 	list_add(&map->list, &regulator_supply_alias_list);
2361 
2362 	pr_info("Adding alias for supply %s,%s -> %s,%s\n",
2363 		id, dev_name(dev), alias_id, dev_name(alias_dev));
2364 
2365 	return 0;
2366 }
2367 EXPORT_SYMBOL_GPL(regulator_register_supply_alias);
2368 
2369 /**
2370  * regulator_unregister_supply_alias - Remove device alias
2371  *
2372  * @dev: device that will be given as the regulator "consumer"
2373  * @id: Supply name or regulator ID
2374  *
2375  * Remove a lookup alias if one exists for id on dev.
2376  */
2377 void regulator_unregister_supply_alias(struct device *dev, const char *id)
2378 {
2379 	struct regulator_supply_alias *map;
2380 
2381 	map = regulator_find_supply_alias(dev, id);
2382 	if (map) {
2383 		list_del(&map->list);
2384 		kfree(map);
2385 	}
2386 }
2387 EXPORT_SYMBOL_GPL(regulator_unregister_supply_alias);
2388 
2389 /**
2390  * regulator_bulk_register_supply_alias - register multiple aliases
2391  *
2392  * @dev: device that will be given as the regulator "consumer"
2393  * @id: List of supply names or regulator IDs
2394  * @alias_dev: device that should be used to lookup the supply
2395  * @alias_id: List of supply names or regulator IDs that should be used to
2396  * lookup the supply
2397  * @num_id: Number of aliases to register
2398  *
2399  * @return 0 on success, an errno on failure.
2400  *
2401  * This helper function allows drivers to register several supply
2402  * aliases in one operation.  If any of the aliases cannot be
2403  * registered any aliases that were registered will be removed
2404  * before returning to the caller.
2405  */
2406 int regulator_bulk_register_supply_alias(struct device *dev,
2407 					 const char *const *id,
2408 					 struct device *alias_dev,
2409 					 const char *const *alias_id,
2410 					 int num_id)
2411 {
2412 	int i;
2413 	int ret;
2414 
2415 	for (i = 0; i < num_id; ++i) {
2416 		ret = regulator_register_supply_alias(dev, id[i], alias_dev,
2417 						      alias_id[i]);
2418 		if (ret < 0)
2419 			goto err;
2420 	}
2421 
2422 	return 0;
2423 
2424 err:
2425 	dev_err(dev,
2426 		"Failed to create supply alias %s,%s -> %s,%s\n",
2427 		id[i], dev_name(dev), alias_id[i], dev_name(alias_dev));
2428 
2429 	while (--i >= 0)
2430 		regulator_unregister_supply_alias(dev, id[i]);
2431 
2432 	return ret;
2433 }
2434 EXPORT_SYMBOL_GPL(regulator_bulk_register_supply_alias);
2435 
2436 /**
2437  * regulator_bulk_unregister_supply_alias - unregister multiple aliases
2438  *
2439  * @dev: device that will be given as the regulator "consumer"
2440  * @id: List of supply names or regulator IDs
2441  * @num_id: Number of aliases to unregister
2442  *
2443  * This helper function allows drivers to unregister several supply
2444  * aliases in one operation.
2445  */
2446 void regulator_bulk_unregister_supply_alias(struct device *dev,
2447 					    const char *const *id,
2448 					    int num_id)
2449 {
2450 	int i;
2451 
2452 	for (i = 0; i < num_id; ++i)
2453 		regulator_unregister_supply_alias(dev, id[i]);
2454 }
2455 EXPORT_SYMBOL_GPL(regulator_bulk_unregister_supply_alias);
2456 
2457 
2458 /* Manage enable GPIO list. Same GPIO pin can be shared among regulators */
2459 static int regulator_ena_gpio_request(struct regulator_dev *rdev,
2460 				const struct regulator_config *config)
2461 {
2462 	struct regulator_enable_gpio *pin, *new_pin;
2463 	struct gpio_desc *gpiod;
2464 
2465 	gpiod = config->ena_gpiod;
2466 	new_pin = kzalloc(sizeof(*new_pin), GFP_KERNEL);
2467 
2468 	mutex_lock(&regulator_list_mutex);
2469 
2470 	list_for_each_entry(pin, &regulator_ena_gpio_list, list) {
2471 		if (pin->gpiod == gpiod) {
2472 			rdev_dbg(rdev, "GPIO is already used\n");
2473 			goto update_ena_gpio_to_rdev;
2474 		}
2475 	}
2476 
2477 	if (new_pin == NULL) {
2478 		mutex_unlock(&regulator_list_mutex);
2479 		return -ENOMEM;
2480 	}
2481 
2482 	pin = new_pin;
2483 	new_pin = NULL;
2484 
2485 	pin->gpiod = gpiod;
2486 	list_add(&pin->list, &regulator_ena_gpio_list);
2487 
2488 update_ena_gpio_to_rdev:
2489 	pin->request_count++;
2490 	rdev->ena_pin = pin;
2491 
2492 	mutex_unlock(&regulator_list_mutex);
2493 	kfree(new_pin);
2494 
2495 	return 0;
2496 }
2497 
2498 static void regulator_ena_gpio_free(struct regulator_dev *rdev)
2499 {
2500 	struct regulator_enable_gpio *pin, *n;
2501 
2502 	if (!rdev->ena_pin)
2503 		return;
2504 
2505 	/* Free the GPIO only in case of no use */
2506 	list_for_each_entry_safe(pin, n, &regulator_ena_gpio_list, list) {
2507 		if (pin != rdev->ena_pin)
2508 			continue;
2509 
2510 		if (--pin->request_count)
2511 			break;
2512 
2513 		gpiod_put(pin->gpiod);
2514 		list_del(&pin->list);
2515 		kfree(pin);
2516 		break;
2517 	}
2518 
2519 	rdev->ena_pin = NULL;
2520 }
2521 
2522 /**
2523  * regulator_ena_gpio_ctrl - balance enable_count of each GPIO and actual GPIO pin control
2524  * @rdev: regulator_dev structure
2525  * @enable: enable GPIO at initial use?
2526  *
2527  * GPIO is enabled in case of initial use. (enable_count is 0)
2528  * GPIO is disabled when it is not shared any more. (enable_count <= 1)
2529  */
2530 static int regulator_ena_gpio_ctrl(struct regulator_dev *rdev, bool enable)
2531 {
2532 	struct regulator_enable_gpio *pin = rdev->ena_pin;
2533 
2534 	if (!pin)
2535 		return -EINVAL;
2536 
2537 	if (enable) {
2538 		/* Enable GPIO at initial use */
2539 		if (pin->enable_count == 0)
2540 			gpiod_set_value_cansleep(pin->gpiod, 1);
2541 
2542 		pin->enable_count++;
2543 	} else {
2544 		if (pin->enable_count > 1) {
2545 			pin->enable_count--;
2546 			return 0;
2547 		}
2548 
2549 		/* Disable GPIO if not used */
2550 		if (pin->enable_count <= 1) {
2551 			gpiod_set_value_cansleep(pin->gpiod, 0);
2552 			pin->enable_count = 0;
2553 		}
2554 	}
2555 
2556 	return 0;
2557 }
2558 
2559 /**
2560  * _regulator_delay_helper - a delay helper function
2561  * @delay: time to delay in microseconds
2562  *
2563  * Delay for the requested amount of time as per the guidelines in:
2564  *
2565  *     Documentation/timers/timers-howto.rst
2566  *
2567  * The assumption here is that these regulator operations will never used in
2568  * atomic context and therefore sleeping functions can be used.
2569  */
2570 static void _regulator_delay_helper(unsigned int delay)
2571 {
2572 	unsigned int ms = delay / 1000;
2573 	unsigned int us = delay % 1000;
2574 
2575 	if (ms > 0) {
2576 		/*
2577 		 * For small enough values, handle super-millisecond
2578 		 * delays in the usleep_range() call below.
2579 		 */
2580 		if (ms < 20)
2581 			us += ms * 1000;
2582 		else
2583 			msleep(ms);
2584 	}
2585 
2586 	/*
2587 	 * Give the scheduler some room to coalesce with any other
2588 	 * wakeup sources. For delays shorter than 10 us, don't even
2589 	 * bother setting up high-resolution timers and just busy-
2590 	 * loop.
2591 	 */
2592 	if (us >= 10)
2593 		usleep_range(us, us + 100);
2594 	else
2595 		udelay(us);
2596 }
2597 
2598 /**
2599  * _regulator_check_status_enabled
2600  *
2601  * A helper function to check if the regulator status can be interpreted
2602  * as 'regulator is enabled'.
2603  * @rdev: the regulator device to check
2604  *
2605  * Return:
2606  * * 1			- if status shows regulator is in enabled state
2607  * * 0			- if not enabled state
2608  * * Error Value	- as received from ops->get_status()
2609  */
2610 static inline int _regulator_check_status_enabled(struct regulator_dev *rdev)
2611 {
2612 	int ret = rdev->desc->ops->get_status(rdev);
2613 
2614 	if (ret < 0) {
2615 		rdev_info(rdev, "get_status returned error: %d\n", ret);
2616 		return ret;
2617 	}
2618 
2619 	switch (ret) {
2620 	case REGULATOR_STATUS_OFF:
2621 	case REGULATOR_STATUS_ERROR:
2622 	case REGULATOR_STATUS_UNDEFINED:
2623 		return 0;
2624 	default:
2625 		return 1;
2626 	}
2627 }
2628 
2629 static int _regulator_do_enable(struct regulator_dev *rdev)
2630 {
2631 	int ret, delay;
2632 
2633 	/* Query before enabling in case configuration dependent.  */
2634 	ret = _regulator_get_enable_time(rdev);
2635 	if (ret >= 0) {
2636 		delay = ret;
2637 	} else {
2638 		rdev_warn(rdev, "enable_time() failed: %pe\n", ERR_PTR(ret));
2639 		delay = 0;
2640 	}
2641 
2642 	trace_regulator_enable(rdev_get_name(rdev));
2643 
2644 	if (rdev->desc->off_on_delay && rdev->last_off) {
2645 		/* if needed, keep a distance of off_on_delay from last time
2646 		 * this regulator was disabled.
2647 		 */
2648 		ktime_t end = ktime_add_us(rdev->last_off, rdev->desc->off_on_delay);
2649 		s64 remaining = ktime_us_delta(end, ktime_get());
2650 
2651 		if (remaining > 0)
2652 			_regulator_delay_helper(remaining);
2653 	}
2654 
2655 	if (rdev->ena_pin) {
2656 		if (!rdev->ena_gpio_state) {
2657 			ret = regulator_ena_gpio_ctrl(rdev, true);
2658 			if (ret < 0)
2659 				return ret;
2660 			rdev->ena_gpio_state = 1;
2661 		}
2662 	} else if (rdev->desc->ops->enable) {
2663 		ret = rdev->desc->ops->enable(rdev);
2664 		if (ret < 0)
2665 			return ret;
2666 	} else {
2667 		return -EINVAL;
2668 	}
2669 
2670 	/* Allow the regulator to ramp; it would be useful to extend
2671 	 * this for bulk operations so that the regulators can ramp
2672 	 * together.
2673 	 */
2674 	trace_regulator_enable_delay(rdev_get_name(rdev));
2675 
2676 	/* If poll_enabled_time is set, poll upto the delay calculated
2677 	 * above, delaying poll_enabled_time uS to check if the regulator
2678 	 * actually got enabled.
2679 	 * If the regulator isn't enabled after our delay helper has expired,
2680 	 * return -ETIMEDOUT.
2681 	 */
2682 	if (rdev->desc->poll_enabled_time) {
2683 		unsigned int time_remaining = delay;
2684 
2685 		while (time_remaining > 0) {
2686 			_regulator_delay_helper(rdev->desc->poll_enabled_time);
2687 
2688 			if (rdev->desc->ops->get_status) {
2689 				ret = _regulator_check_status_enabled(rdev);
2690 				if (ret < 0)
2691 					return ret;
2692 				else if (ret)
2693 					break;
2694 			} else if (rdev->desc->ops->is_enabled(rdev))
2695 				break;
2696 
2697 			time_remaining -= rdev->desc->poll_enabled_time;
2698 		}
2699 
2700 		if (time_remaining <= 0) {
2701 			rdev_err(rdev, "Enabled check timed out\n");
2702 			return -ETIMEDOUT;
2703 		}
2704 	} else {
2705 		_regulator_delay_helper(delay);
2706 	}
2707 
2708 	trace_regulator_enable_complete(rdev_get_name(rdev));
2709 
2710 	return 0;
2711 }
2712 
2713 /**
2714  * _regulator_handle_consumer_enable - handle that a consumer enabled
2715  * @regulator: regulator source
2716  *
2717  * Some things on a regulator consumer (like the contribution towards total
2718  * load on the regulator) only have an effect when the consumer wants the
2719  * regulator enabled.  Explained in example with two consumers of the same
2720  * regulator:
2721  *   consumer A: set_load(100);       => total load = 0
2722  *   consumer A: regulator_enable();  => total load = 100
2723  *   consumer B: set_load(1000);      => total load = 100
2724  *   consumer B: regulator_enable();  => total load = 1100
2725  *   consumer A: regulator_disable(); => total_load = 1000
2726  *
2727  * This function (together with _regulator_handle_consumer_disable) is
2728  * responsible for keeping track of the refcount for a given regulator consumer
2729  * and applying / unapplying these things.
2730  *
2731  * Returns 0 upon no error; -error upon error.
2732  */
2733 static int _regulator_handle_consumer_enable(struct regulator *regulator)
2734 {
2735 	struct regulator_dev *rdev = regulator->rdev;
2736 
2737 	lockdep_assert_held_once(&rdev->mutex.base);
2738 
2739 	regulator->enable_count++;
2740 	if (regulator->uA_load && regulator->enable_count == 1)
2741 		return drms_uA_update(rdev);
2742 
2743 	return 0;
2744 }
2745 
2746 /**
2747  * _regulator_handle_consumer_disable - handle that a consumer disabled
2748  * @regulator: regulator source
2749  *
2750  * The opposite of _regulator_handle_consumer_enable().
2751  *
2752  * Returns 0 upon no error; -error upon error.
2753  */
2754 static int _regulator_handle_consumer_disable(struct regulator *regulator)
2755 {
2756 	struct regulator_dev *rdev = regulator->rdev;
2757 
2758 	lockdep_assert_held_once(&rdev->mutex.base);
2759 
2760 	if (!regulator->enable_count) {
2761 		rdev_err(rdev, "Underflow of regulator enable count\n");
2762 		return -EINVAL;
2763 	}
2764 
2765 	regulator->enable_count--;
2766 	if (regulator->uA_load && regulator->enable_count == 0)
2767 		return drms_uA_update(rdev);
2768 
2769 	return 0;
2770 }
2771 
2772 /* locks held by regulator_enable() */
2773 static int _regulator_enable(struct regulator *regulator)
2774 {
2775 	struct regulator_dev *rdev = regulator->rdev;
2776 	int ret;
2777 
2778 	lockdep_assert_held_once(&rdev->mutex.base);
2779 
2780 	if (rdev->use_count == 0 && rdev->supply) {
2781 		ret = _regulator_enable(rdev->supply);
2782 		if (ret < 0)
2783 			return ret;
2784 	}
2785 
2786 	/* balance only if there are regulators coupled */
2787 	if (rdev->coupling_desc.n_coupled > 1) {
2788 		ret = regulator_balance_voltage(rdev, PM_SUSPEND_ON);
2789 		if (ret < 0)
2790 			goto err_disable_supply;
2791 	}
2792 
2793 	ret = _regulator_handle_consumer_enable(regulator);
2794 	if (ret < 0)
2795 		goto err_disable_supply;
2796 
2797 	if (rdev->use_count == 0) {
2798 		/*
2799 		 * The regulator may already be enabled if it's not switchable
2800 		 * or was left on
2801 		 */
2802 		ret = _regulator_is_enabled(rdev);
2803 		if (ret == -EINVAL || ret == 0) {
2804 			if (!regulator_ops_is_valid(rdev,
2805 					REGULATOR_CHANGE_STATUS)) {
2806 				ret = -EPERM;
2807 				goto err_consumer_disable;
2808 			}
2809 
2810 			ret = _regulator_do_enable(rdev);
2811 			if (ret < 0)
2812 				goto err_consumer_disable;
2813 
2814 			_notifier_call_chain(rdev, REGULATOR_EVENT_ENABLE,
2815 					     NULL);
2816 		} else if (ret < 0) {
2817 			rdev_err(rdev, "is_enabled() failed: %pe\n", ERR_PTR(ret));
2818 			goto err_consumer_disable;
2819 		}
2820 		/* Fallthrough on positive return values - already enabled */
2821 	}
2822 
2823 	rdev->use_count++;
2824 
2825 	return 0;
2826 
2827 err_consumer_disable:
2828 	_regulator_handle_consumer_disable(regulator);
2829 
2830 err_disable_supply:
2831 	if (rdev->use_count == 0 && rdev->supply)
2832 		_regulator_disable(rdev->supply);
2833 
2834 	return ret;
2835 }
2836 
2837 /**
2838  * regulator_enable - enable regulator output
2839  * @regulator: regulator source
2840  *
2841  * Request that the regulator be enabled with the regulator output at
2842  * the predefined voltage or current value.  Calls to regulator_enable()
2843  * must be balanced with calls to regulator_disable().
2844  *
2845  * NOTE: the output value can be set by other drivers, boot loader or may be
2846  * hardwired in the regulator.
2847  */
2848 int regulator_enable(struct regulator *regulator)
2849 {
2850 	struct regulator_dev *rdev = regulator->rdev;
2851 	struct ww_acquire_ctx ww_ctx;
2852 	int ret;
2853 
2854 	regulator_lock_dependent(rdev, &ww_ctx);
2855 	ret = _regulator_enable(regulator);
2856 	regulator_unlock_dependent(rdev, &ww_ctx);
2857 
2858 	return ret;
2859 }
2860 EXPORT_SYMBOL_GPL(regulator_enable);
2861 
2862 static int _regulator_do_disable(struct regulator_dev *rdev)
2863 {
2864 	int ret;
2865 
2866 	trace_regulator_disable(rdev_get_name(rdev));
2867 
2868 	if (rdev->ena_pin) {
2869 		if (rdev->ena_gpio_state) {
2870 			ret = regulator_ena_gpio_ctrl(rdev, false);
2871 			if (ret < 0)
2872 				return ret;
2873 			rdev->ena_gpio_state = 0;
2874 		}
2875 
2876 	} else if (rdev->desc->ops->disable) {
2877 		ret = rdev->desc->ops->disable(rdev);
2878 		if (ret != 0)
2879 			return ret;
2880 	}
2881 
2882 	if (rdev->desc->off_on_delay)
2883 		rdev->last_off = ktime_get();
2884 
2885 	trace_regulator_disable_complete(rdev_get_name(rdev));
2886 
2887 	return 0;
2888 }
2889 
2890 /* locks held by regulator_disable() */
2891 static int _regulator_disable(struct regulator *regulator)
2892 {
2893 	struct regulator_dev *rdev = regulator->rdev;
2894 	int ret = 0;
2895 
2896 	lockdep_assert_held_once(&rdev->mutex.base);
2897 
2898 	if (WARN(rdev->use_count <= 0,
2899 		 "unbalanced disables for %s\n", rdev_get_name(rdev)))
2900 		return -EIO;
2901 
2902 	/* are we the last user and permitted to disable ? */
2903 	if (rdev->use_count == 1 &&
2904 	    (rdev->constraints && !rdev->constraints->always_on)) {
2905 
2906 		/* we are last user */
2907 		if (regulator_ops_is_valid(rdev, REGULATOR_CHANGE_STATUS)) {
2908 			ret = _notifier_call_chain(rdev,
2909 						   REGULATOR_EVENT_PRE_DISABLE,
2910 						   NULL);
2911 			if (ret & NOTIFY_STOP_MASK)
2912 				return -EINVAL;
2913 
2914 			ret = _regulator_do_disable(rdev);
2915 			if (ret < 0) {
2916 				rdev_err(rdev, "failed to disable: %pe\n", ERR_PTR(ret));
2917 				_notifier_call_chain(rdev,
2918 						REGULATOR_EVENT_ABORT_DISABLE,
2919 						NULL);
2920 				return ret;
2921 			}
2922 			_notifier_call_chain(rdev, REGULATOR_EVENT_DISABLE,
2923 					NULL);
2924 		}
2925 
2926 		rdev->use_count = 0;
2927 	} else if (rdev->use_count > 1) {
2928 		rdev->use_count--;
2929 	}
2930 
2931 	if (ret == 0)
2932 		ret = _regulator_handle_consumer_disable(regulator);
2933 
2934 	if (ret == 0 && rdev->coupling_desc.n_coupled > 1)
2935 		ret = regulator_balance_voltage(rdev, PM_SUSPEND_ON);
2936 
2937 	if (ret == 0 && rdev->use_count == 0 && rdev->supply)
2938 		ret = _regulator_disable(rdev->supply);
2939 
2940 	return ret;
2941 }
2942 
2943 /**
2944  * regulator_disable - disable regulator output
2945  * @regulator: regulator source
2946  *
2947  * Disable the regulator output voltage or current.  Calls to
2948  * regulator_enable() must be balanced with calls to
2949  * regulator_disable().
2950  *
2951  * NOTE: this will only disable the regulator output if no other consumer
2952  * devices have it enabled, the regulator device supports disabling and
2953  * machine constraints permit this operation.
2954  */
2955 int regulator_disable(struct regulator *regulator)
2956 {
2957 	struct regulator_dev *rdev = regulator->rdev;
2958 	struct ww_acquire_ctx ww_ctx;
2959 	int ret;
2960 
2961 	regulator_lock_dependent(rdev, &ww_ctx);
2962 	ret = _regulator_disable(regulator);
2963 	regulator_unlock_dependent(rdev, &ww_ctx);
2964 
2965 	return ret;
2966 }
2967 EXPORT_SYMBOL_GPL(regulator_disable);
2968 
2969 /* locks held by regulator_force_disable() */
2970 static int _regulator_force_disable(struct regulator_dev *rdev)
2971 {
2972 	int ret = 0;
2973 
2974 	lockdep_assert_held_once(&rdev->mutex.base);
2975 
2976 	ret = _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
2977 			REGULATOR_EVENT_PRE_DISABLE, NULL);
2978 	if (ret & NOTIFY_STOP_MASK)
2979 		return -EINVAL;
2980 
2981 	ret = _regulator_do_disable(rdev);
2982 	if (ret < 0) {
2983 		rdev_err(rdev, "failed to force disable: %pe\n", ERR_PTR(ret));
2984 		_notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
2985 				REGULATOR_EVENT_ABORT_DISABLE, NULL);
2986 		return ret;
2987 	}
2988 
2989 	_notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
2990 			REGULATOR_EVENT_DISABLE, NULL);
2991 
2992 	return 0;
2993 }
2994 
2995 /**
2996  * regulator_force_disable - force disable regulator output
2997  * @regulator: regulator source
2998  *
2999  * Forcibly disable the regulator output voltage or current.
3000  * NOTE: this *will* disable the regulator output even if other consumer
3001  * devices have it enabled. This should be used for situations when device
3002  * damage will likely occur if the regulator is not disabled (e.g. over temp).
3003  */
3004 int regulator_force_disable(struct regulator *regulator)
3005 {
3006 	struct regulator_dev *rdev = regulator->rdev;
3007 	struct ww_acquire_ctx ww_ctx;
3008 	int ret;
3009 
3010 	regulator_lock_dependent(rdev, &ww_ctx);
3011 
3012 	ret = _regulator_force_disable(regulator->rdev);
3013 
3014 	if (rdev->coupling_desc.n_coupled > 1)
3015 		regulator_balance_voltage(rdev, PM_SUSPEND_ON);
3016 
3017 	if (regulator->uA_load) {
3018 		regulator->uA_load = 0;
3019 		ret = drms_uA_update(rdev);
3020 	}
3021 
3022 	if (rdev->use_count != 0 && rdev->supply)
3023 		_regulator_disable(rdev->supply);
3024 
3025 	regulator_unlock_dependent(rdev, &ww_ctx);
3026 
3027 	return ret;
3028 }
3029 EXPORT_SYMBOL_GPL(regulator_force_disable);
3030 
3031 static void regulator_disable_work(struct work_struct *work)
3032 {
3033 	struct regulator_dev *rdev = container_of(work, struct regulator_dev,
3034 						  disable_work.work);
3035 	struct ww_acquire_ctx ww_ctx;
3036 	int count, i, ret;
3037 	struct regulator *regulator;
3038 	int total_count = 0;
3039 
3040 	regulator_lock_dependent(rdev, &ww_ctx);
3041 
3042 	/*
3043 	 * Workqueue functions queue the new work instance while the previous
3044 	 * work instance is being processed. Cancel the queued work instance
3045 	 * as the work instance under processing does the job of the queued
3046 	 * work instance.
3047 	 */
3048 	cancel_delayed_work(&rdev->disable_work);
3049 
3050 	list_for_each_entry(regulator, &rdev->consumer_list, list) {
3051 		count = regulator->deferred_disables;
3052 
3053 		if (!count)
3054 			continue;
3055 
3056 		total_count += count;
3057 		regulator->deferred_disables = 0;
3058 
3059 		for (i = 0; i < count; i++) {
3060 			ret = _regulator_disable(regulator);
3061 			if (ret != 0)
3062 				rdev_err(rdev, "Deferred disable failed: %pe\n",
3063 					 ERR_PTR(ret));
3064 		}
3065 	}
3066 	WARN_ON(!total_count);
3067 
3068 	if (rdev->coupling_desc.n_coupled > 1)
3069 		regulator_balance_voltage(rdev, PM_SUSPEND_ON);
3070 
3071 	regulator_unlock_dependent(rdev, &ww_ctx);
3072 }
3073 
3074 /**
3075  * regulator_disable_deferred - disable regulator output with delay
3076  * @regulator: regulator source
3077  * @ms: milliseconds until the regulator is disabled
3078  *
3079  * Execute regulator_disable() on the regulator after a delay.  This
3080  * is intended for use with devices that require some time to quiesce.
3081  *
3082  * NOTE: this will only disable the regulator output if no other consumer
3083  * devices have it enabled, the regulator device supports disabling and
3084  * machine constraints permit this operation.
3085  */
3086 int regulator_disable_deferred(struct regulator *regulator, int ms)
3087 {
3088 	struct regulator_dev *rdev = regulator->rdev;
3089 
3090 	if (!ms)
3091 		return regulator_disable(regulator);
3092 
3093 	regulator_lock(rdev);
3094 	regulator->deferred_disables++;
3095 	mod_delayed_work(system_power_efficient_wq, &rdev->disable_work,
3096 			 msecs_to_jiffies(ms));
3097 	regulator_unlock(rdev);
3098 
3099 	return 0;
3100 }
3101 EXPORT_SYMBOL_GPL(regulator_disable_deferred);
3102 
3103 static int _regulator_is_enabled(struct regulator_dev *rdev)
3104 {
3105 	/* A GPIO control always takes precedence */
3106 	if (rdev->ena_pin)
3107 		return rdev->ena_gpio_state;
3108 
3109 	/* If we don't know then assume that the regulator is always on */
3110 	if (!rdev->desc->ops->is_enabled)
3111 		return 1;
3112 
3113 	return rdev->desc->ops->is_enabled(rdev);
3114 }
3115 
3116 static int _regulator_list_voltage(struct regulator_dev *rdev,
3117 				   unsigned selector, int lock)
3118 {
3119 	const struct regulator_ops *ops = rdev->desc->ops;
3120 	int ret;
3121 
3122 	if (rdev->desc->fixed_uV && rdev->desc->n_voltages == 1 && !selector)
3123 		return rdev->desc->fixed_uV;
3124 
3125 	if (ops->list_voltage) {
3126 		if (selector >= rdev->desc->n_voltages)
3127 			return -EINVAL;
3128 		if (selector < rdev->desc->linear_min_sel)
3129 			return 0;
3130 		if (lock)
3131 			regulator_lock(rdev);
3132 		ret = ops->list_voltage(rdev, selector);
3133 		if (lock)
3134 			regulator_unlock(rdev);
3135 	} else if (rdev->is_switch && rdev->supply) {
3136 		ret = _regulator_list_voltage(rdev->supply->rdev,
3137 					      selector, lock);
3138 	} else {
3139 		return -EINVAL;
3140 	}
3141 
3142 	if (ret > 0) {
3143 		if (ret < rdev->constraints->min_uV)
3144 			ret = 0;
3145 		else if (ret > rdev->constraints->max_uV)
3146 			ret = 0;
3147 	}
3148 
3149 	return ret;
3150 }
3151 
3152 /**
3153  * regulator_is_enabled - is the regulator output enabled
3154  * @regulator: regulator source
3155  *
3156  * Returns positive if the regulator driver backing the source/client
3157  * has requested that the device be enabled, zero if it hasn't, else a
3158  * negative errno code.
3159  *
3160  * Note that the device backing this regulator handle can have multiple
3161  * users, so it might be enabled even if regulator_enable() was never
3162  * called for this particular source.
3163  */
3164 int regulator_is_enabled(struct regulator *regulator)
3165 {
3166 	int ret;
3167 
3168 	if (regulator->always_on)
3169 		return 1;
3170 
3171 	regulator_lock(regulator->rdev);
3172 	ret = _regulator_is_enabled(regulator->rdev);
3173 	regulator_unlock(regulator->rdev);
3174 
3175 	return ret;
3176 }
3177 EXPORT_SYMBOL_GPL(regulator_is_enabled);
3178 
3179 /**
3180  * regulator_count_voltages - count regulator_list_voltage() selectors
3181  * @regulator: regulator source
3182  *
3183  * Returns number of selectors, or negative errno.  Selectors are
3184  * numbered starting at zero, and typically correspond to bitfields
3185  * in hardware registers.
3186  */
3187 int regulator_count_voltages(struct regulator *regulator)
3188 {
3189 	struct regulator_dev	*rdev = regulator->rdev;
3190 
3191 	if (rdev->desc->n_voltages)
3192 		return rdev->desc->n_voltages;
3193 
3194 	if (!rdev->is_switch || !rdev->supply)
3195 		return -EINVAL;
3196 
3197 	return regulator_count_voltages(rdev->supply);
3198 }
3199 EXPORT_SYMBOL_GPL(regulator_count_voltages);
3200 
3201 /**
3202  * regulator_list_voltage - enumerate supported voltages
3203  * @regulator: regulator source
3204  * @selector: identify voltage to list
3205  * Context: can sleep
3206  *
3207  * Returns a voltage that can be passed to @regulator_set_voltage(),
3208  * zero if this selector code can't be used on this system, or a
3209  * negative errno.
3210  */
3211 int regulator_list_voltage(struct regulator *regulator, unsigned selector)
3212 {
3213 	return _regulator_list_voltage(regulator->rdev, selector, 1);
3214 }
3215 EXPORT_SYMBOL_GPL(regulator_list_voltage);
3216 
3217 /**
3218  * regulator_get_regmap - get the regulator's register map
3219  * @regulator: regulator source
3220  *
3221  * Returns the register map for the given regulator, or an ERR_PTR value
3222  * if the regulator doesn't use regmap.
3223  */
3224 struct regmap *regulator_get_regmap(struct regulator *regulator)
3225 {
3226 	struct regmap *map = regulator->rdev->regmap;
3227 
3228 	return map ? map : ERR_PTR(-EOPNOTSUPP);
3229 }
3230 
3231 /**
3232  * regulator_get_hardware_vsel_register - get the HW voltage selector register
3233  * @regulator: regulator source
3234  * @vsel_reg: voltage selector register, output parameter
3235  * @vsel_mask: mask for voltage selector bitfield, output parameter
3236  *
3237  * Returns the hardware register offset and bitmask used for setting the
3238  * regulator voltage. This might be useful when configuring voltage-scaling
3239  * hardware or firmware that can make I2C requests behind the kernel's back,
3240  * for example.
3241  *
3242  * On success, the output parameters @vsel_reg and @vsel_mask are filled in
3243  * and 0 is returned, otherwise a negative errno is returned.
3244  */
3245 int regulator_get_hardware_vsel_register(struct regulator *regulator,
3246 					 unsigned *vsel_reg,
3247 					 unsigned *vsel_mask)
3248 {
3249 	struct regulator_dev *rdev = regulator->rdev;
3250 	const struct regulator_ops *ops = rdev->desc->ops;
3251 
3252 	if (ops->set_voltage_sel != regulator_set_voltage_sel_regmap)
3253 		return -EOPNOTSUPP;
3254 
3255 	*vsel_reg = rdev->desc->vsel_reg;
3256 	*vsel_mask = rdev->desc->vsel_mask;
3257 
3258 	return 0;
3259 }
3260 EXPORT_SYMBOL_GPL(regulator_get_hardware_vsel_register);
3261 
3262 /**
3263  * regulator_list_hardware_vsel - get the HW-specific register value for a selector
3264  * @regulator: regulator source
3265  * @selector: identify voltage to list
3266  *
3267  * Converts the selector to a hardware-specific voltage selector that can be
3268  * directly written to the regulator registers. The address of the voltage
3269  * register can be determined by calling @regulator_get_hardware_vsel_register.
3270  *
3271  * On error a negative errno is returned.
3272  */
3273 int regulator_list_hardware_vsel(struct regulator *regulator,
3274 				 unsigned selector)
3275 {
3276 	struct regulator_dev *rdev = regulator->rdev;
3277 	const struct regulator_ops *ops = rdev->desc->ops;
3278 
3279 	if (selector >= rdev->desc->n_voltages)
3280 		return -EINVAL;
3281 	if (selector < rdev->desc->linear_min_sel)
3282 		return 0;
3283 	if (ops->set_voltage_sel != regulator_set_voltage_sel_regmap)
3284 		return -EOPNOTSUPP;
3285 
3286 	return selector;
3287 }
3288 EXPORT_SYMBOL_GPL(regulator_list_hardware_vsel);
3289 
3290 /**
3291  * regulator_get_linear_step - return the voltage step size between VSEL values
3292  * @regulator: regulator source
3293  *
3294  * Returns the voltage step size between VSEL values for linear
3295  * regulators, or return 0 if the regulator isn't a linear regulator.
3296  */
3297 unsigned int regulator_get_linear_step(struct regulator *regulator)
3298 {
3299 	struct regulator_dev *rdev = regulator->rdev;
3300 
3301 	return rdev->desc->uV_step;
3302 }
3303 EXPORT_SYMBOL_GPL(regulator_get_linear_step);
3304 
3305 /**
3306  * regulator_is_supported_voltage - check if a voltage range can be supported
3307  *
3308  * @regulator: Regulator to check.
3309  * @min_uV: Minimum required voltage in uV.
3310  * @max_uV: Maximum required voltage in uV.
3311  *
3312  * Returns a boolean.
3313  */
3314 int regulator_is_supported_voltage(struct regulator *regulator,
3315 				   int min_uV, int max_uV)
3316 {
3317 	struct regulator_dev *rdev = regulator->rdev;
3318 	int i, voltages, ret;
3319 
3320 	/* If we can't change voltage check the current voltage */
3321 	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE)) {
3322 		ret = regulator_get_voltage(regulator);
3323 		if (ret >= 0)
3324 			return min_uV <= ret && ret <= max_uV;
3325 		else
3326 			return ret;
3327 	}
3328 
3329 	/* Any voltage within constrains range is fine? */
3330 	if (rdev->desc->continuous_voltage_range)
3331 		return min_uV >= rdev->constraints->min_uV &&
3332 				max_uV <= rdev->constraints->max_uV;
3333 
3334 	ret = regulator_count_voltages(regulator);
3335 	if (ret < 0)
3336 		return 0;
3337 	voltages = ret;
3338 
3339 	for (i = 0; i < voltages; i++) {
3340 		ret = regulator_list_voltage(regulator, i);
3341 
3342 		if (ret >= min_uV && ret <= max_uV)
3343 			return 1;
3344 	}
3345 
3346 	return 0;
3347 }
3348 EXPORT_SYMBOL_GPL(regulator_is_supported_voltage);
3349 
3350 static int regulator_map_voltage(struct regulator_dev *rdev, int min_uV,
3351 				 int max_uV)
3352 {
3353 	const struct regulator_desc *desc = rdev->desc;
3354 
3355 	if (desc->ops->map_voltage)
3356 		return desc->ops->map_voltage(rdev, min_uV, max_uV);
3357 
3358 	if (desc->ops->list_voltage == regulator_list_voltage_linear)
3359 		return regulator_map_voltage_linear(rdev, min_uV, max_uV);
3360 
3361 	if (desc->ops->list_voltage == regulator_list_voltage_linear_range)
3362 		return regulator_map_voltage_linear_range(rdev, min_uV, max_uV);
3363 
3364 	if (desc->ops->list_voltage ==
3365 		regulator_list_voltage_pickable_linear_range)
3366 		return regulator_map_voltage_pickable_linear_range(rdev,
3367 							min_uV, max_uV);
3368 
3369 	return regulator_map_voltage_iterate(rdev, min_uV, max_uV);
3370 }
3371 
3372 static int _regulator_call_set_voltage(struct regulator_dev *rdev,
3373 				       int min_uV, int max_uV,
3374 				       unsigned *selector)
3375 {
3376 	struct pre_voltage_change_data data;
3377 	int ret;
3378 
3379 	data.old_uV = regulator_get_voltage_rdev(rdev);
3380 	data.min_uV = min_uV;
3381 	data.max_uV = max_uV;
3382 	ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE,
3383 				   &data);
3384 	if (ret & NOTIFY_STOP_MASK)
3385 		return -EINVAL;
3386 
3387 	ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV, selector);
3388 	if (ret >= 0)
3389 		return ret;
3390 
3391 	_notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE,
3392 			     (void *)data.old_uV);
3393 
3394 	return ret;
3395 }
3396 
3397 static int _regulator_call_set_voltage_sel(struct regulator_dev *rdev,
3398 					   int uV, unsigned selector)
3399 {
3400 	struct pre_voltage_change_data data;
3401 	int ret;
3402 
3403 	data.old_uV = regulator_get_voltage_rdev(rdev);
3404 	data.min_uV = uV;
3405 	data.max_uV = uV;
3406 	ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE,
3407 				   &data);
3408 	if (ret & NOTIFY_STOP_MASK)
3409 		return -EINVAL;
3410 
3411 	ret = rdev->desc->ops->set_voltage_sel(rdev, selector);
3412 	if (ret >= 0)
3413 		return ret;
3414 
3415 	_notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE,
3416 			     (void *)data.old_uV);
3417 
3418 	return ret;
3419 }
3420 
3421 static int _regulator_set_voltage_sel_step(struct regulator_dev *rdev,
3422 					   int uV, int new_selector)
3423 {
3424 	const struct regulator_ops *ops = rdev->desc->ops;
3425 	int diff, old_sel, curr_sel, ret;
3426 
3427 	/* Stepping is only needed if the regulator is enabled. */
3428 	if (!_regulator_is_enabled(rdev))
3429 		goto final_set;
3430 
3431 	if (!ops->get_voltage_sel)
3432 		return -EINVAL;
3433 
3434 	old_sel = ops->get_voltage_sel(rdev);
3435 	if (old_sel < 0)
3436 		return old_sel;
3437 
3438 	diff = new_selector - old_sel;
3439 	if (diff == 0)
3440 		return 0; /* No change needed. */
3441 
3442 	if (diff > 0) {
3443 		/* Stepping up. */
3444 		for (curr_sel = old_sel + rdev->desc->vsel_step;
3445 		     curr_sel < new_selector;
3446 		     curr_sel += rdev->desc->vsel_step) {
3447 			/*
3448 			 * Call the callback directly instead of using
3449 			 * _regulator_call_set_voltage_sel() as we don't
3450 			 * want to notify anyone yet. Same in the branch
3451 			 * below.
3452 			 */
3453 			ret = ops->set_voltage_sel(rdev, curr_sel);
3454 			if (ret)
3455 				goto try_revert;
3456 		}
3457 	} else {
3458 		/* Stepping down. */
3459 		for (curr_sel = old_sel - rdev->desc->vsel_step;
3460 		     curr_sel > new_selector;
3461 		     curr_sel -= rdev->desc->vsel_step) {
3462 			ret = ops->set_voltage_sel(rdev, curr_sel);
3463 			if (ret)
3464 				goto try_revert;
3465 		}
3466 	}
3467 
3468 final_set:
3469 	/* The final selector will trigger the notifiers. */
3470 	return _regulator_call_set_voltage_sel(rdev, uV, new_selector);
3471 
3472 try_revert:
3473 	/*
3474 	 * At least try to return to the previous voltage if setting a new
3475 	 * one failed.
3476 	 */
3477 	(void)ops->set_voltage_sel(rdev, old_sel);
3478 	return ret;
3479 }
3480 
3481 static int _regulator_set_voltage_time(struct regulator_dev *rdev,
3482 				       int old_uV, int new_uV)
3483 {
3484 	unsigned int ramp_delay = 0;
3485 
3486 	if (rdev->constraints->ramp_delay)
3487 		ramp_delay = rdev->constraints->ramp_delay;
3488 	else if (rdev->desc->ramp_delay)
3489 		ramp_delay = rdev->desc->ramp_delay;
3490 	else if (rdev->constraints->settling_time)
3491 		return rdev->constraints->settling_time;
3492 	else if (rdev->constraints->settling_time_up &&
3493 		 (new_uV > old_uV))
3494 		return rdev->constraints->settling_time_up;
3495 	else if (rdev->constraints->settling_time_down &&
3496 		 (new_uV < old_uV))
3497 		return rdev->constraints->settling_time_down;
3498 
3499 	if (ramp_delay == 0) {
3500 		rdev_dbg(rdev, "ramp_delay not set\n");
3501 		return 0;
3502 	}
3503 
3504 	return DIV_ROUND_UP(abs(new_uV - old_uV), ramp_delay);
3505 }
3506 
3507 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
3508 				     int min_uV, int max_uV)
3509 {
3510 	int ret;
3511 	int delay = 0;
3512 	int best_val = 0;
3513 	unsigned int selector;
3514 	int old_selector = -1;
3515 	const struct regulator_ops *ops = rdev->desc->ops;
3516 	int old_uV = regulator_get_voltage_rdev(rdev);
3517 
3518 	trace_regulator_set_voltage(rdev_get_name(rdev), min_uV, max_uV);
3519 
3520 	min_uV += rdev->constraints->uV_offset;
3521 	max_uV += rdev->constraints->uV_offset;
3522 
3523 	/*
3524 	 * If we can't obtain the old selector there is not enough
3525 	 * info to call set_voltage_time_sel().
3526 	 */
3527 	if (_regulator_is_enabled(rdev) &&
3528 	    ops->set_voltage_time_sel && ops->get_voltage_sel) {
3529 		old_selector = ops->get_voltage_sel(rdev);
3530 		if (old_selector < 0)
3531 			return old_selector;
3532 	}
3533 
3534 	if (ops->set_voltage) {
3535 		ret = _regulator_call_set_voltage(rdev, min_uV, max_uV,
3536 						  &selector);
3537 
3538 		if (ret >= 0) {
3539 			if (ops->list_voltage)
3540 				best_val = ops->list_voltage(rdev,
3541 							     selector);
3542 			else
3543 				best_val = regulator_get_voltage_rdev(rdev);
3544 		}
3545 
3546 	} else if (ops->set_voltage_sel) {
3547 		ret = regulator_map_voltage(rdev, min_uV, max_uV);
3548 		if (ret >= 0) {
3549 			best_val = ops->list_voltage(rdev, ret);
3550 			if (min_uV <= best_val && max_uV >= best_val) {
3551 				selector = ret;
3552 				if (old_selector == selector)
3553 					ret = 0;
3554 				else if (rdev->desc->vsel_step)
3555 					ret = _regulator_set_voltage_sel_step(
3556 						rdev, best_val, selector);
3557 				else
3558 					ret = _regulator_call_set_voltage_sel(
3559 						rdev, best_val, selector);
3560 			} else {
3561 				ret = -EINVAL;
3562 			}
3563 		}
3564 	} else {
3565 		ret = -EINVAL;
3566 	}
3567 
3568 	if (ret)
3569 		goto out;
3570 
3571 	if (ops->set_voltage_time_sel) {
3572 		/*
3573 		 * Call set_voltage_time_sel if successfully obtained
3574 		 * old_selector
3575 		 */
3576 		if (old_selector >= 0 && old_selector != selector)
3577 			delay = ops->set_voltage_time_sel(rdev, old_selector,
3578 							  selector);
3579 	} else {
3580 		if (old_uV != best_val) {
3581 			if (ops->set_voltage_time)
3582 				delay = ops->set_voltage_time(rdev, old_uV,
3583 							      best_val);
3584 			else
3585 				delay = _regulator_set_voltage_time(rdev,
3586 								    old_uV,
3587 								    best_val);
3588 		}
3589 	}
3590 
3591 	if (delay < 0) {
3592 		rdev_warn(rdev, "failed to get delay: %pe\n", ERR_PTR(delay));
3593 		delay = 0;
3594 	}
3595 
3596 	/* Insert any necessary delays */
3597 	_regulator_delay_helper(delay);
3598 
3599 	if (best_val >= 0) {
3600 		unsigned long data = best_val;
3601 
3602 		_notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE,
3603 				     (void *)data);
3604 	}
3605 
3606 out:
3607 	trace_regulator_set_voltage_complete(rdev_get_name(rdev), best_val);
3608 
3609 	return ret;
3610 }
3611 
3612 static int _regulator_do_set_suspend_voltage(struct regulator_dev *rdev,
3613 				  int min_uV, int max_uV, suspend_state_t state)
3614 {
3615 	struct regulator_state *rstate;
3616 	int uV, sel;
3617 
3618 	rstate = regulator_get_suspend_state(rdev, state);
3619 	if (rstate == NULL)
3620 		return -EINVAL;
3621 
3622 	if (min_uV < rstate->min_uV)
3623 		min_uV = rstate->min_uV;
3624 	if (max_uV > rstate->max_uV)
3625 		max_uV = rstate->max_uV;
3626 
3627 	sel = regulator_map_voltage(rdev, min_uV, max_uV);
3628 	if (sel < 0)
3629 		return sel;
3630 
3631 	uV = rdev->desc->ops->list_voltage(rdev, sel);
3632 	if (uV >= min_uV && uV <= max_uV)
3633 		rstate->uV = uV;
3634 
3635 	return 0;
3636 }
3637 
3638 static int regulator_set_voltage_unlocked(struct regulator *regulator,
3639 					  int min_uV, int max_uV,
3640 					  suspend_state_t state)
3641 {
3642 	struct regulator_dev *rdev = regulator->rdev;
3643 	struct regulator_voltage *voltage = &regulator->voltage[state];
3644 	int ret = 0;
3645 	int old_min_uV, old_max_uV;
3646 	int current_uV;
3647 
3648 	/* If we're setting the same range as last time the change
3649 	 * should be a noop (some cpufreq implementations use the same
3650 	 * voltage for multiple frequencies, for example).
3651 	 */
3652 	if (voltage->min_uV == min_uV && voltage->max_uV == max_uV)
3653 		goto out;
3654 
3655 	/* If we're trying to set a range that overlaps the current voltage,
3656 	 * return successfully even though the regulator does not support
3657 	 * changing the voltage.
3658 	 */
3659 	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE)) {
3660 		current_uV = regulator_get_voltage_rdev(rdev);
3661 		if (min_uV <= current_uV && current_uV <= max_uV) {
3662 			voltage->min_uV = min_uV;
3663 			voltage->max_uV = max_uV;
3664 			goto out;
3665 		}
3666 	}
3667 
3668 	/* sanity check */
3669 	if (!rdev->desc->ops->set_voltage &&
3670 	    !rdev->desc->ops->set_voltage_sel) {
3671 		ret = -EINVAL;
3672 		goto out;
3673 	}
3674 
3675 	/* constraints check */
3676 	ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
3677 	if (ret < 0)
3678 		goto out;
3679 
3680 	/* restore original values in case of error */
3681 	old_min_uV = voltage->min_uV;
3682 	old_max_uV = voltage->max_uV;
3683 	voltage->min_uV = min_uV;
3684 	voltage->max_uV = max_uV;
3685 
3686 	/* for not coupled regulators this will just set the voltage */
3687 	ret = regulator_balance_voltage(rdev, state);
3688 	if (ret < 0) {
3689 		voltage->min_uV = old_min_uV;
3690 		voltage->max_uV = old_max_uV;
3691 	}
3692 
3693 out:
3694 	return ret;
3695 }
3696 
3697 int regulator_set_voltage_rdev(struct regulator_dev *rdev, int min_uV,
3698 			       int max_uV, suspend_state_t state)
3699 {
3700 	int best_supply_uV = 0;
3701 	int supply_change_uV = 0;
3702 	int ret;
3703 
3704 	if (rdev->supply &&
3705 	    regulator_ops_is_valid(rdev->supply->rdev,
3706 				   REGULATOR_CHANGE_VOLTAGE) &&
3707 	    (rdev->desc->min_dropout_uV || !(rdev->desc->ops->get_voltage ||
3708 					   rdev->desc->ops->get_voltage_sel))) {
3709 		int current_supply_uV;
3710 		int selector;
3711 
3712 		selector = regulator_map_voltage(rdev, min_uV, max_uV);
3713 		if (selector < 0) {
3714 			ret = selector;
3715 			goto out;
3716 		}
3717 
3718 		best_supply_uV = _regulator_list_voltage(rdev, selector, 0);
3719 		if (best_supply_uV < 0) {
3720 			ret = best_supply_uV;
3721 			goto out;
3722 		}
3723 
3724 		best_supply_uV += rdev->desc->min_dropout_uV;
3725 
3726 		current_supply_uV = regulator_get_voltage_rdev(rdev->supply->rdev);
3727 		if (current_supply_uV < 0) {
3728 			ret = current_supply_uV;
3729 			goto out;
3730 		}
3731 
3732 		supply_change_uV = best_supply_uV - current_supply_uV;
3733 	}
3734 
3735 	if (supply_change_uV > 0) {
3736 		ret = regulator_set_voltage_unlocked(rdev->supply,
3737 				best_supply_uV, INT_MAX, state);
3738 		if (ret) {
3739 			dev_err(&rdev->dev, "Failed to increase supply voltage: %pe\n",
3740 				ERR_PTR(ret));
3741 			goto out;
3742 		}
3743 	}
3744 
3745 	if (state == PM_SUSPEND_ON)
3746 		ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
3747 	else
3748 		ret = _regulator_do_set_suspend_voltage(rdev, min_uV,
3749 							max_uV, state);
3750 	if (ret < 0)
3751 		goto out;
3752 
3753 	if (supply_change_uV < 0) {
3754 		ret = regulator_set_voltage_unlocked(rdev->supply,
3755 				best_supply_uV, INT_MAX, state);
3756 		if (ret)
3757 			dev_warn(&rdev->dev, "Failed to decrease supply voltage: %pe\n",
3758 				 ERR_PTR(ret));
3759 		/* No need to fail here */
3760 		ret = 0;
3761 	}
3762 
3763 out:
3764 	return ret;
3765 }
3766 EXPORT_SYMBOL_GPL(regulator_set_voltage_rdev);
3767 
3768 static int regulator_limit_voltage_step(struct regulator_dev *rdev,
3769 					int *current_uV, int *min_uV)
3770 {
3771 	struct regulation_constraints *constraints = rdev->constraints;
3772 
3773 	/* Limit voltage change only if necessary */
3774 	if (!constraints->max_uV_step || !_regulator_is_enabled(rdev))
3775 		return 1;
3776 
3777 	if (*current_uV < 0) {
3778 		*current_uV = regulator_get_voltage_rdev(rdev);
3779 
3780 		if (*current_uV < 0)
3781 			return *current_uV;
3782 	}
3783 
3784 	if (abs(*current_uV - *min_uV) <= constraints->max_uV_step)
3785 		return 1;
3786 
3787 	/* Clamp target voltage within the given step */
3788 	if (*current_uV < *min_uV)
3789 		*min_uV = min(*current_uV + constraints->max_uV_step,
3790 			      *min_uV);
3791 	else
3792 		*min_uV = max(*current_uV - constraints->max_uV_step,
3793 			      *min_uV);
3794 
3795 	return 0;
3796 }
3797 
3798 static int regulator_get_optimal_voltage(struct regulator_dev *rdev,
3799 					 int *current_uV,
3800 					 int *min_uV, int *max_uV,
3801 					 suspend_state_t state,
3802 					 int n_coupled)
3803 {
3804 	struct coupling_desc *c_desc = &rdev->coupling_desc;
3805 	struct regulator_dev **c_rdevs = c_desc->coupled_rdevs;
3806 	struct regulation_constraints *constraints = rdev->constraints;
3807 	int desired_min_uV = 0, desired_max_uV = INT_MAX;
3808 	int max_current_uV = 0, min_current_uV = INT_MAX;
3809 	int highest_min_uV = 0, target_uV, possible_uV;
3810 	int i, ret, max_spread;
3811 	bool done;
3812 
3813 	*current_uV = -1;
3814 
3815 	/*
3816 	 * If there are no coupled regulators, simply set the voltage
3817 	 * demanded by consumers.
3818 	 */
3819 	if (n_coupled == 1) {
3820 		/*
3821 		 * If consumers don't provide any demands, set voltage
3822 		 * to min_uV
3823 		 */
3824 		desired_min_uV = constraints->min_uV;
3825 		desired_max_uV = constraints->max_uV;
3826 
3827 		ret = regulator_check_consumers(rdev,
3828 						&desired_min_uV,
3829 						&desired_max_uV, state);
3830 		if (ret < 0)
3831 			return ret;
3832 
3833 		possible_uV = desired_min_uV;
3834 		done = true;
3835 
3836 		goto finish;
3837 	}
3838 
3839 	/* Find highest min desired voltage */
3840 	for (i = 0; i < n_coupled; i++) {
3841 		int tmp_min = 0;
3842 		int tmp_max = INT_MAX;
3843 
3844 		lockdep_assert_held_once(&c_rdevs[i]->mutex.base);
3845 
3846 		ret = regulator_check_consumers(c_rdevs[i],
3847 						&tmp_min,
3848 						&tmp_max, state);
3849 		if (ret < 0)
3850 			return ret;
3851 
3852 		ret = regulator_check_voltage(c_rdevs[i], &tmp_min, &tmp_max);
3853 		if (ret < 0)
3854 			return ret;
3855 
3856 		highest_min_uV = max(highest_min_uV, tmp_min);
3857 
3858 		if (i == 0) {
3859 			desired_min_uV = tmp_min;
3860 			desired_max_uV = tmp_max;
3861 		}
3862 	}
3863 
3864 	max_spread = constraints->max_spread[0];
3865 
3866 	/*
3867 	 * Let target_uV be equal to the desired one if possible.
3868 	 * If not, set it to minimum voltage, allowed by other coupled
3869 	 * regulators.
3870 	 */
3871 	target_uV = max(desired_min_uV, highest_min_uV - max_spread);
3872 
3873 	/*
3874 	 * Find min and max voltages, which currently aren't violating
3875 	 * max_spread.
3876 	 */
3877 	for (i = 1; i < n_coupled; i++) {
3878 		int tmp_act;
3879 
3880 		if (!_regulator_is_enabled(c_rdevs[i]))
3881 			continue;
3882 
3883 		tmp_act = regulator_get_voltage_rdev(c_rdevs[i]);
3884 		if (tmp_act < 0)
3885 			return tmp_act;
3886 
3887 		min_current_uV = min(tmp_act, min_current_uV);
3888 		max_current_uV = max(tmp_act, max_current_uV);
3889 	}
3890 
3891 	/* There aren't any other regulators enabled */
3892 	if (max_current_uV == 0) {
3893 		possible_uV = target_uV;
3894 	} else {
3895 		/*
3896 		 * Correct target voltage, so as it currently isn't
3897 		 * violating max_spread
3898 		 */
3899 		possible_uV = max(target_uV, max_current_uV - max_spread);
3900 		possible_uV = min(possible_uV, min_current_uV + max_spread);
3901 	}
3902 
3903 	if (possible_uV > desired_max_uV)
3904 		return -EINVAL;
3905 
3906 	done = (possible_uV == target_uV);
3907 	desired_min_uV = possible_uV;
3908 
3909 finish:
3910 	/* Apply max_uV_step constraint if necessary */
3911 	if (state == PM_SUSPEND_ON) {
3912 		ret = regulator_limit_voltage_step(rdev, current_uV,
3913 						   &desired_min_uV);
3914 		if (ret < 0)
3915 			return ret;
3916 
3917 		if (ret == 0)
3918 			done = false;
3919 	}
3920 
3921 	/* Set current_uV if wasn't done earlier in the code and if necessary */
3922 	if (n_coupled > 1 && *current_uV == -1) {
3923 
3924 		if (_regulator_is_enabled(rdev)) {
3925 			ret = regulator_get_voltage_rdev(rdev);
3926 			if (ret < 0)
3927 				return ret;
3928 
3929 			*current_uV = ret;
3930 		} else {
3931 			*current_uV = desired_min_uV;
3932 		}
3933 	}
3934 
3935 	*min_uV = desired_min_uV;
3936 	*max_uV = desired_max_uV;
3937 
3938 	return done;
3939 }
3940 
3941 int regulator_do_balance_voltage(struct regulator_dev *rdev,
3942 				 suspend_state_t state, bool skip_coupled)
3943 {
3944 	struct regulator_dev **c_rdevs;
3945 	struct regulator_dev *best_rdev;
3946 	struct coupling_desc *c_desc = &rdev->coupling_desc;
3947 	int i, ret, n_coupled, best_min_uV, best_max_uV, best_c_rdev;
3948 	unsigned int delta, best_delta;
3949 	unsigned long c_rdev_done = 0;
3950 	bool best_c_rdev_done;
3951 
3952 	c_rdevs = c_desc->coupled_rdevs;
3953 	n_coupled = skip_coupled ? 1 : c_desc->n_coupled;
3954 
3955 	/*
3956 	 * Find the best possible voltage change on each loop. Leave the loop
3957 	 * if there isn't any possible change.
3958 	 */
3959 	do {
3960 		best_c_rdev_done = false;
3961 		best_delta = 0;
3962 		best_min_uV = 0;
3963 		best_max_uV = 0;
3964 		best_c_rdev = 0;
3965 		best_rdev = NULL;
3966 
3967 		/*
3968 		 * Find highest difference between optimal voltage
3969 		 * and current voltage.
3970 		 */
3971 		for (i = 0; i < n_coupled; i++) {
3972 			/*
3973 			 * optimal_uV is the best voltage that can be set for
3974 			 * i-th regulator at the moment without violating
3975 			 * max_spread constraint in order to balance
3976 			 * the coupled voltages.
3977 			 */
3978 			int optimal_uV = 0, optimal_max_uV = 0, current_uV = 0;
3979 
3980 			if (test_bit(i, &c_rdev_done))
3981 				continue;
3982 
3983 			ret = regulator_get_optimal_voltage(c_rdevs[i],
3984 							    &current_uV,
3985 							    &optimal_uV,
3986 							    &optimal_max_uV,
3987 							    state, n_coupled);
3988 			if (ret < 0)
3989 				goto out;
3990 
3991 			delta = abs(optimal_uV - current_uV);
3992 
3993 			if (delta && best_delta <= delta) {
3994 				best_c_rdev_done = ret;
3995 				best_delta = delta;
3996 				best_rdev = c_rdevs[i];
3997 				best_min_uV = optimal_uV;
3998 				best_max_uV = optimal_max_uV;
3999 				best_c_rdev = i;
4000 			}
4001 		}
4002 
4003 		/* Nothing to change, return successfully */
4004 		if (!best_rdev) {
4005 			ret = 0;
4006 			goto out;
4007 		}
4008 
4009 		ret = regulator_set_voltage_rdev(best_rdev, best_min_uV,
4010 						 best_max_uV, state);
4011 
4012 		if (ret < 0)
4013 			goto out;
4014 
4015 		if (best_c_rdev_done)
4016 			set_bit(best_c_rdev, &c_rdev_done);
4017 
4018 	} while (n_coupled > 1);
4019 
4020 out:
4021 	return ret;
4022 }
4023 
4024 static int regulator_balance_voltage(struct regulator_dev *rdev,
4025 				     suspend_state_t state)
4026 {
4027 	struct coupling_desc *c_desc = &rdev->coupling_desc;
4028 	struct regulator_coupler *coupler = c_desc->coupler;
4029 	bool skip_coupled = false;
4030 
4031 	/*
4032 	 * If system is in a state other than PM_SUSPEND_ON, don't check
4033 	 * other coupled regulators.
4034 	 */
4035 	if (state != PM_SUSPEND_ON)
4036 		skip_coupled = true;
4037 
4038 	if (c_desc->n_resolved < c_desc->n_coupled) {
4039 		rdev_err(rdev, "Not all coupled regulators registered\n");
4040 		return -EPERM;
4041 	}
4042 
4043 	/* Invoke custom balancer for customized couplers */
4044 	if (coupler && coupler->balance_voltage)
4045 		return coupler->balance_voltage(coupler, rdev, state);
4046 
4047 	return regulator_do_balance_voltage(rdev, state, skip_coupled);
4048 }
4049 
4050 /**
4051  * regulator_set_voltage - set regulator output voltage
4052  * @regulator: regulator source
4053  * @min_uV: Minimum required voltage in uV
4054  * @max_uV: Maximum acceptable voltage in uV
4055  *
4056  * Sets a voltage regulator to the desired output voltage. This can be set
4057  * during any regulator state. IOW, regulator can be disabled or enabled.
4058  *
4059  * If the regulator is enabled then the voltage will change to the new value
4060  * immediately otherwise if the regulator is disabled the regulator will
4061  * output at the new voltage when enabled.
4062  *
4063  * NOTE: If the regulator is shared between several devices then the lowest
4064  * request voltage that meets the system constraints will be used.
4065  * Regulator system constraints must be set for this regulator before
4066  * calling this function otherwise this call will fail.
4067  */
4068 int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
4069 {
4070 	struct ww_acquire_ctx ww_ctx;
4071 	int ret;
4072 
4073 	regulator_lock_dependent(regulator->rdev, &ww_ctx);
4074 
4075 	ret = regulator_set_voltage_unlocked(regulator, min_uV, max_uV,
4076 					     PM_SUSPEND_ON);
4077 
4078 	regulator_unlock_dependent(regulator->rdev, &ww_ctx);
4079 
4080 	return ret;
4081 }
4082 EXPORT_SYMBOL_GPL(regulator_set_voltage);
4083 
4084 static inline int regulator_suspend_toggle(struct regulator_dev *rdev,
4085 					   suspend_state_t state, bool en)
4086 {
4087 	struct regulator_state *rstate;
4088 
4089 	rstate = regulator_get_suspend_state(rdev, state);
4090 	if (rstate == NULL)
4091 		return -EINVAL;
4092 
4093 	if (!rstate->changeable)
4094 		return -EPERM;
4095 
4096 	rstate->enabled = (en) ? ENABLE_IN_SUSPEND : DISABLE_IN_SUSPEND;
4097 
4098 	return 0;
4099 }
4100 
4101 int regulator_suspend_enable(struct regulator_dev *rdev,
4102 				    suspend_state_t state)
4103 {
4104 	return regulator_suspend_toggle(rdev, state, true);
4105 }
4106 EXPORT_SYMBOL_GPL(regulator_suspend_enable);
4107 
4108 int regulator_suspend_disable(struct regulator_dev *rdev,
4109 				     suspend_state_t state)
4110 {
4111 	struct regulator *regulator;
4112 	struct regulator_voltage *voltage;
4113 
4114 	/*
4115 	 * if any consumer wants this regulator device keeping on in
4116 	 * suspend states, don't set it as disabled.
4117 	 */
4118 	list_for_each_entry(regulator, &rdev->consumer_list, list) {
4119 		voltage = &regulator->voltage[state];
4120 		if (voltage->min_uV || voltage->max_uV)
4121 			return 0;
4122 	}
4123 
4124 	return regulator_suspend_toggle(rdev, state, false);
4125 }
4126 EXPORT_SYMBOL_GPL(regulator_suspend_disable);
4127 
4128 static int _regulator_set_suspend_voltage(struct regulator *regulator,
4129 					  int min_uV, int max_uV,
4130 					  suspend_state_t state)
4131 {
4132 	struct regulator_dev *rdev = regulator->rdev;
4133 	struct regulator_state *rstate;
4134 
4135 	rstate = regulator_get_suspend_state(rdev, state);
4136 	if (rstate == NULL)
4137 		return -EINVAL;
4138 
4139 	if (rstate->min_uV == rstate->max_uV) {
4140 		rdev_err(rdev, "The suspend voltage can't be changed!\n");
4141 		return -EPERM;
4142 	}
4143 
4144 	return regulator_set_voltage_unlocked(regulator, min_uV, max_uV, state);
4145 }
4146 
4147 int regulator_set_suspend_voltage(struct regulator *regulator, int min_uV,
4148 				  int max_uV, suspend_state_t state)
4149 {
4150 	struct ww_acquire_ctx ww_ctx;
4151 	int ret;
4152 
4153 	/* PM_SUSPEND_ON is handled by regulator_set_voltage() */
4154 	if (regulator_check_states(state) || state == PM_SUSPEND_ON)
4155 		return -EINVAL;
4156 
4157 	regulator_lock_dependent(regulator->rdev, &ww_ctx);
4158 
4159 	ret = _regulator_set_suspend_voltage(regulator, min_uV,
4160 					     max_uV, state);
4161 
4162 	regulator_unlock_dependent(regulator->rdev, &ww_ctx);
4163 
4164 	return ret;
4165 }
4166 EXPORT_SYMBOL_GPL(regulator_set_suspend_voltage);
4167 
4168 /**
4169  * regulator_set_voltage_time - get raise/fall time
4170  * @regulator: regulator source
4171  * @old_uV: starting voltage in microvolts
4172  * @new_uV: target voltage in microvolts
4173  *
4174  * Provided with the starting and ending voltage, this function attempts to
4175  * calculate the time in microseconds required to rise or fall to this new
4176  * voltage.
4177  */
4178 int regulator_set_voltage_time(struct regulator *regulator,
4179 			       int old_uV, int new_uV)
4180 {
4181 	struct regulator_dev *rdev = regulator->rdev;
4182 	const struct regulator_ops *ops = rdev->desc->ops;
4183 	int old_sel = -1;
4184 	int new_sel = -1;
4185 	int voltage;
4186 	int i;
4187 
4188 	if (ops->set_voltage_time)
4189 		return ops->set_voltage_time(rdev, old_uV, new_uV);
4190 	else if (!ops->set_voltage_time_sel)
4191 		return _regulator_set_voltage_time(rdev, old_uV, new_uV);
4192 
4193 	/* Currently requires operations to do this */
4194 	if (!ops->list_voltage || !rdev->desc->n_voltages)
4195 		return -EINVAL;
4196 
4197 	for (i = 0; i < rdev->desc->n_voltages; i++) {
4198 		/* We only look for exact voltage matches here */
4199 		if (i < rdev->desc->linear_min_sel)
4200 			continue;
4201 
4202 		if (old_sel >= 0 && new_sel >= 0)
4203 			break;
4204 
4205 		voltage = regulator_list_voltage(regulator, i);
4206 		if (voltage < 0)
4207 			return -EINVAL;
4208 		if (voltage == 0)
4209 			continue;
4210 		if (voltage == old_uV)
4211 			old_sel = i;
4212 		if (voltage == new_uV)
4213 			new_sel = i;
4214 	}
4215 
4216 	if (old_sel < 0 || new_sel < 0)
4217 		return -EINVAL;
4218 
4219 	return ops->set_voltage_time_sel(rdev, old_sel, new_sel);
4220 }
4221 EXPORT_SYMBOL_GPL(regulator_set_voltage_time);
4222 
4223 /**
4224  * regulator_set_voltage_time_sel - get raise/fall time
4225  * @rdev: regulator source device
4226  * @old_selector: selector for starting voltage
4227  * @new_selector: selector for target voltage
4228  *
4229  * Provided with the starting and target voltage selectors, this function
4230  * returns time in microseconds required to rise or fall to this new voltage
4231  *
4232  * Drivers providing ramp_delay in regulation_constraints can use this as their
4233  * set_voltage_time_sel() operation.
4234  */
4235 int regulator_set_voltage_time_sel(struct regulator_dev *rdev,
4236 				   unsigned int old_selector,
4237 				   unsigned int new_selector)
4238 {
4239 	int old_volt, new_volt;
4240 
4241 	/* sanity check */
4242 	if (!rdev->desc->ops->list_voltage)
4243 		return -EINVAL;
4244 
4245 	old_volt = rdev->desc->ops->list_voltage(rdev, old_selector);
4246 	new_volt = rdev->desc->ops->list_voltage(rdev, new_selector);
4247 
4248 	if (rdev->desc->ops->set_voltage_time)
4249 		return rdev->desc->ops->set_voltage_time(rdev, old_volt,
4250 							 new_volt);
4251 	else
4252 		return _regulator_set_voltage_time(rdev, old_volt, new_volt);
4253 }
4254 EXPORT_SYMBOL_GPL(regulator_set_voltage_time_sel);
4255 
4256 int regulator_sync_voltage_rdev(struct regulator_dev *rdev)
4257 {
4258 	int ret;
4259 
4260 	regulator_lock(rdev);
4261 
4262 	if (!rdev->desc->ops->set_voltage &&
4263 	    !rdev->desc->ops->set_voltage_sel) {
4264 		ret = -EINVAL;
4265 		goto out;
4266 	}
4267 
4268 	/* balance only, if regulator is coupled */
4269 	if (rdev->coupling_desc.n_coupled > 1)
4270 		ret = regulator_balance_voltage(rdev, PM_SUSPEND_ON);
4271 	else
4272 		ret = -EOPNOTSUPP;
4273 
4274 out:
4275 	regulator_unlock(rdev);
4276 	return ret;
4277 }
4278 
4279 /**
4280  * regulator_sync_voltage - re-apply last regulator output voltage
4281  * @regulator: regulator source
4282  *
4283  * Re-apply the last configured voltage.  This is intended to be used
4284  * where some external control source the consumer is cooperating with
4285  * has caused the configured voltage to change.
4286  */
4287 int regulator_sync_voltage(struct regulator *regulator)
4288 {
4289 	struct regulator_dev *rdev = regulator->rdev;
4290 	struct regulator_voltage *voltage = &regulator->voltage[PM_SUSPEND_ON];
4291 	int ret, min_uV, max_uV;
4292 
4293 	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE))
4294 		return 0;
4295 
4296 	regulator_lock(rdev);
4297 
4298 	if (!rdev->desc->ops->set_voltage &&
4299 	    !rdev->desc->ops->set_voltage_sel) {
4300 		ret = -EINVAL;
4301 		goto out;
4302 	}
4303 
4304 	/* This is only going to work if we've had a voltage configured. */
4305 	if (!voltage->min_uV && !voltage->max_uV) {
4306 		ret = -EINVAL;
4307 		goto out;
4308 	}
4309 
4310 	min_uV = voltage->min_uV;
4311 	max_uV = voltage->max_uV;
4312 
4313 	/* This should be a paranoia check... */
4314 	ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
4315 	if (ret < 0)
4316 		goto out;
4317 
4318 	ret = regulator_check_consumers(rdev, &min_uV, &max_uV, 0);
4319 	if (ret < 0)
4320 		goto out;
4321 
4322 	/* balance only, if regulator is coupled */
4323 	if (rdev->coupling_desc.n_coupled > 1)
4324 		ret = regulator_balance_voltage(rdev, PM_SUSPEND_ON);
4325 	else
4326 		ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
4327 
4328 out:
4329 	regulator_unlock(rdev);
4330 	return ret;
4331 }
4332 EXPORT_SYMBOL_GPL(regulator_sync_voltage);
4333 
4334 int regulator_get_voltage_rdev(struct regulator_dev *rdev)
4335 {
4336 	int sel, ret;
4337 	bool bypassed;
4338 
4339 	if (rdev->desc->ops->get_bypass) {
4340 		ret = rdev->desc->ops->get_bypass(rdev, &bypassed);
4341 		if (ret < 0)
4342 			return ret;
4343 		if (bypassed) {
4344 			/* if bypassed the regulator must have a supply */
4345 			if (!rdev->supply) {
4346 				rdev_err(rdev,
4347 					 "bypassed regulator has no supply!\n");
4348 				return -EPROBE_DEFER;
4349 			}
4350 
4351 			return regulator_get_voltage_rdev(rdev->supply->rdev);
4352 		}
4353 	}
4354 
4355 	if (rdev->desc->ops->get_voltage_sel) {
4356 		sel = rdev->desc->ops->get_voltage_sel(rdev);
4357 		if (sel < 0)
4358 			return sel;
4359 		ret = rdev->desc->ops->list_voltage(rdev, sel);
4360 	} else if (rdev->desc->ops->get_voltage) {
4361 		ret = rdev->desc->ops->get_voltage(rdev);
4362 	} else if (rdev->desc->ops->list_voltage) {
4363 		ret = rdev->desc->ops->list_voltage(rdev, 0);
4364 	} else if (rdev->desc->fixed_uV && (rdev->desc->n_voltages == 1)) {
4365 		ret = rdev->desc->fixed_uV;
4366 	} else if (rdev->supply) {
4367 		ret = regulator_get_voltage_rdev(rdev->supply->rdev);
4368 	} else if (rdev->supply_name) {
4369 		return -EPROBE_DEFER;
4370 	} else {
4371 		return -EINVAL;
4372 	}
4373 
4374 	if (ret < 0)
4375 		return ret;
4376 	return ret - rdev->constraints->uV_offset;
4377 }
4378 EXPORT_SYMBOL_GPL(regulator_get_voltage_rdev);
4379 
4380 /**
4381  * regulator_get_voltage - get regulator output voltage
4382  * @regulator: regulator source
4383  *
4384  * This returns the current regulator voltage in uV.
4385  *
4386  * NOTE: If the regulator is disabled it will return the voltage value. This
4387  * function should not be used to determine regulator state.
4388  */
4389 int regulator_get_voltage(struct regulator *regulator)
4390 {
4391 	struct ww_acquire_ctx ww_ctx;
4392 	int ret;
4393 
4394 	regulator_lock_dependent(regulator->rdev, &ww_ctx);
4395 	ret = regulator_get_voltage_rdev(regulator->rdev);
4396 	regulator_unlock_dependent(regulator->rdev, &ww_ctx);
4397 
4398 	return ret;
4399 }
4400 EXPORT_SYMBOL_GPL(regulator_get_voltage);
4401 
4402 /**
4403  * regulator_set_current_limit - set regulator output current limit
4404  * @regulator: regulator source
4405  * @min_uA: Minimum supported current in uA
4406  * @max_uA: Maximum supported current in uA
4407  *
4408  * Sets current sink to the desired output current. This can be set during
4409  * any regulator state. IOW, regulator can be disabled or enabled.
4410  *
4411  * If the regulator is enabled then the current will change to the new value
4412  * immediately otherwise if the regulator is disabled the regulator will
4413  * output at the new current when enabled.
4414  *
4415  * NOTE: Regulator system constraints must be set for this regulator before
4416  * calling this function otherwise this call will fail.
4417  */
4418 int regulator_set_current_limit(struct regulator *regulator,
4419 			       int min_uA, int max_uA)
4420 {
4421 	struct regulator_dev *rdev = regulator->rdev;
4422 	int ret;
4423 
4424 	regulator_lock(rdev);
4425 
4426 	/* sanity check */
4427 	if (!rdev->desc->ops->set_current_limit) {
4428 		ret = -EINVAL;
4429 		goto out;
4430 	}
4431 
4432 	/* constraints check */
4433 	ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
4434 	if (ret < 0)
4435 		goto out;
4436 
4437 	ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
4438 out:
4439 	regulator_unlock(rdev);
4440 	return ret;
4441 }
4442 EXPORT_SYMBOL_GPL(regulator_set_current_limit);
4443 
4444 static int _regulator_get_current_limit_unlocked(struct regulator_dev *rdev)
4445 {
4446 	/* sanity check */
4447 	if (!rdev->desc->ops->get_current_limit)
4448 		return -EINVAL;
4449 
4450 	return rdev->desc->ops->get_current_limit(rdev);
4451 }
4452 
4453 static int _regulator_get_current_limit(struct regulator_dev *rdev)
4454 {
4455 	int ret;
4456 
4457 	regulator_lock(rdev);
4458 	ret = _regulator_get_current_limit_unlocked(rdev);
4459 	regulator_unlock(rdev);
4460 
4461 	return ret;
4462 }
4463 
4464 /**
4465  * regulator_get_current_limit - get regulator output current
4466  * @regulator: regulator source
4467  *
4468  * This returns the current supplied by the specified current sink in uA.
4469  *
4470  * NOTE: If the regulator is disabled it will return the current value. This
4471  * function should not be used to determine regulator state.
4472  */
4473 int regulator_get_current_limit(struct regulator *regulator)
4474 {
4475 	return _regulator_get_current_limit(regulator->rdev);
4476 }
4477 EXPORT_SYMBOL_GPL(regulator_get_current_limit);
4478 
4479 /**
4480  * regulator_set_mode - set regulator operating mode
4481  * @regulator: regulator source
4482  * @mode: operating mode - one of the REGULATOR_MODE constants
4483  *
4484  * Set regulator operating mode to increase regulator efficiency or improve
4485  * regulation performance.
4486  *
4487  * NOTE: Regulator system constraints must be set for this regulator before
4488  * calling this function otherwise this call will fail.
4489  */
4490 int regulator_set_mode(struct regulator *regulator, unsigned int mode)
4491 {
4492 	struct regulator_dev *rdev = regulator->rdev;
4493 	int ret;
4494 	int regulator_curr_mode;
4495 
4496 	regulator_lock(rdev);
4497 
4498 	/* sanity check */
4499 	if (!rdev->desc->ops->set_mode) {
4500 		ret = -EINVAL;
4501 		goto out;
4502 	}
4503 
4504 	/* return if the same mode is requested */
4505 	if (rdev->desc->ops->get_mode) {
4506 		regulator_curr_mode = rdev->desc->ops->get_mode(rdev);
4507 		if (regulator_curr_mode == mode) {
4508 			ret = 0;
4509 			goto out;
4510 		}
4511 	}
4512 
4513 	/* constraints check */
4514 	ret = regulator_mode_constrain(rdev, &mode);
4515 	if (ret < 0)
4516 		goto out;
4517 
4518 	ret = rdev->desc->ops->set_mode(rdev, mode);
4519 out:
4520 	regulator_unlock(rdev);
4521 	return ret;
4522 }
4523 EXPORT_SYMBOL_GPL(regulator_set_mode);
4524 
4525 static unsigned int _regulator_get_mode_unlocked(struct regulator_dev *rdev)
4526 {
4527 	/* sanity check */
4528 	if (!rdev->desc->ops->get_mode)
4529 		return -EINVAL;
4530 
4531 	return rdev->desc->ops->get_mode(rdev);
4532 }
4533 
4534 static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
4535 {
4536 	int ret;
4537 
4538 	regulator_lock(rdev);
4539 	ret = _regulator_get_mode_unlocked(rdev);
4540 	regulator_unlock(rdev);
4541 
4542 	return ret;
4543 }
4544 
4545 /**
4546  * regulator_get_mode - get regulator operating mode
4547  * @regulator: regulator source
4548  *
4549  * Get the current regulator operating mode.
4550  */
4551 unsigned int regulator_get_mode(struct regulator *regulator)
4552 {
4553 	return _regulator_get_mode(regulator->rdev);
4554 }
4555 EXPORT_SYMBOL_GPL(regulator_get_mode);
4556 
4557 static int rdev_get_cached_err_flags(struct regulator_dev *rdev)
4558 {
4559 	int ret = 0;
4560 
4561 	if (rdev->use_cached_err) {
4562 		spin_lock(&rdev->err_lock);
4563 		ret = rdev->cached_err;
4564 		spin_unlock(&rdev->err_lock);
4565 	}
4566 	return ret;
4567 }
4568 
4569 static int _regulator_get_error_flags(struct regulator_dev *rdev,
4570 					unsigned int *flags)
4571 {
4572 	int cached_flags, ret = 0;
4573 
4574 	regulator_lock(rdev);
4575 
4576 	cached_flags = rdev_get_cached_err_flags(rdev);
4577 
4578 	if (rdev->desc->ops->get_error_flags)
4579 		ret = rdev->desc->ops->get_error_flags(rdev, flags);
4580 	else if (!rdev->use_cached_err)
4581 		ret = -EINVAL;
4582 
4583 	*flags |= cached_flags;
4584 
4585 	regulator_unlock(rdev);
4586 
4587 	return ret;
4588 }
4589 
4590 /**
4591  * regulator_get_error_flags - get regulator error information
4592  * @regulator: regulator source
4593  * @flags: pointer to store error flags
4594  *
4595  * Get the current regulator error information.
4596  */
4597 int regulator_get_error_flags(struct regulator *regulator,
4598 				unsigned int *flags)
4599 {
4600 	return _regulator_get_error_flags(regulator->rdev, flags);
4601 }
4602 EXPORT_SYMBOL_GPL(regulator_get_error_flags);
4603 
4604 /**
4605  * regulator_set_load - set regulator load
4606  * @regulator: regulator source
4607  * @uA_load: load current
4608  *
4609  * Notifies the regulator core of a new device load. This is then used by
4610  * DRMS (if enabled by constraints) to set the most efficient regulator
4611  * operating mode for the new regulator loading.
4612  *
4613  * Consumer devices notify their supply regulator of the maximum power
4614  * they will require (can be taken from device datasheet in the power
4615  * consumption tables) when they change operational status and hence power
4616  * state. Examples of operational state changes that can affect power
4617  * consumption are :-
4618  *
4619  *    o Device is opened / closed.
4620  *    o Device I/O is about to begin or has just finished.
4621  *    o Device is idling in between work.
4622  *
4623  * This information is also exported via sysfs to userspace.
4624  *
4625  * DRMS will sum the total requested load on the regulator and change
4626  * to the most efficient operating mode if platform constraints allow.
4627  *
4628  * NOTE: when a regulator consumer requests to have a regulator
4629  * disabled then any load that consumer requested no longer counts
4630  * toward the total requested load.  If the regulator is re-enabled
4631  * then the previously requested load will start counting again.
4632  *
4633  * If a regulator is an always-on regulator then an individual consumer's
4634  * load will still be removed if that consumer is fully disabled.
4635  *
4636  * On error a negative errno is returned.
4637  */
4638 int regulator_set_load(struct regulator *regulator, int uA_load)
4639 {
4640 	struct regulator_dev *rdev = regulator->rdev;
4641 	int old_uA_load;
4642 	int ret = 0;
4643 
4644 	regulator_lock(rdev);
4645 	old_uA_load = regulator->uA_load;
4646 	regulator->uA_load = uA_load;
4647 	if (regulator->enable_count && old_uA_load != uA_load) {
4648 		ret = drms_uA_update(rdev);
4649 		if (ret < 0)
4650 			regulator->uA_load = old_uA_load;
4651 	}
4652 	regulator_unlock(rdev);
4653 
4654 	return ret;
4655 }
4656 EXPORT_SYMBOL_GPL(regulator_set_load);
4657 
4658 /**
4659  * regulator_allow_bypass - allow the regulator to go into bypass mode
4660  *
4661  * @regulator: Regulator to configure
4662  * @enable: enable or disable bypass mode
4663  *
4664  * Allow the regulator to go into bypass mode if all other consumers
4665  * for the regulator also enable bypass mode and the machine
4666  * constraints allow this.  Bypass mode means that the regulator is
4667  * simply passing the input directly to the output with no regulation.
4668  */
4669 int regulator_allow_bypass(struct regulator *regulator, bool enable)
4670 {
4671 	struct regulator_dev *rdev = regulator->rdev;
4672 	const char *name = rdev_get_name(rdev);
4673 	int ret = 0;
4674 
4675 	if (!rdev->desc->ops->set_bypass)
4676 		return 0;
4677 
4678 	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_BYPASS))
4679 		return 0;
4680 
4681 	regulator_lock(rdev);
4682 
4683 	if (enable && !regulator->bypass) {
4684 		rdev->bypass_count++;
4685 
4686 		if (rdev->bypass_count == rdev->open_count) {
4687 			trace_regulator_bypass_enable(name);
4688 
4689 			ret = rdev->desc->ops->set_bypass(rdev, enable);
4690 			if (ret != 0)
4691 				rdev->bypass_count--;
4692 			else
4693 				trace_regulator_bypass_enable_complete(name);
4694 		}
4695 
4696 	} else if (!enable && regulator->bypass) {
4697 		rdev->bypass_count--;
4698 
4699 		if (rdev->bypass_count != rdev->open_count) {
4700 			trace_regulator_bypass_disable(name);
4701 
4702 			ret = rdev->desc->ops->set_bypass(rdev, enable);
4703 			if (ret != 0)
4704 				rdev->bypass_count++;
4705 			else
4706 				trace_regulator_bypass_disable_complete(name);
4707 		}
4708 	}
4709 
4710 	if (ret == 0)
4711 		regulator->bypass = enable;
4712 
4713 	regulator_unlock(rdev);
4714 
4715 	return ret;
4716 }
4717 EXPORT_SYMBOL_GPL(regulator_allow_bypass);
4718 
4719 /**
4720  * regulator_register_notifier - register regulator event notifier
4721  * @regulator: regulator source
4722  * @nb: notifier block
4723  *
4724  * Register notifier block to receive regulator events.
4725  */
4726 int regulator_register_notifier(struct regulator *regulator,
4727 			      struct notifier_block *nb)
4728 {
4729 	return blocking_notifier_chain_register(&regulator->rdev->notifier,
4730 						nb);
4731 }
4732 EXPORT_SYMBOL_GPL(regulator_register_notifier);
4733 
4734 /**
4735  * regulator_unregister_notifier - unregister regulator event notifier
4736  * @regulator: regulator source
4737  * @nb: notifier block
4738  *
4739  * Unregister regulator event notifier block.
4740  */
4741 int regulator_unregister_notifier(struct regulator *regulator,
4742 				struct notifier_block *nb)
4743 {
4744 	return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
4745 						  nb);
4746 }
4747 EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
4748 
4749 /* notify regulator consumers and downstream regulator consumers.
4750  * Note mutex must be held by caller.
4751  */
4752 static int _notifier_call_chain(struct regulator_dev *rdev,
4753 				  unsigned long event, void *data)
4754 {
4755 	/* call rdev chain first */
4756 	return blocking_notifier_call_chain(&rdev->notifier, event, data);
4757 }
4758 
4759 /**
4760  * regulator_bulk_get - get multiple regulator consumers
4761  *
4762  * @dev:           Device to supply
4763  * @num_consumers: Number of consumers to register
4764  * @consumers:     Configuration of consumers; clients are stored here.
4765  *
4766  * @return 0 on success, an errno on failure.
4767  *
4768  * This helper function allows drivers to get several regulator
4769  * consumers in one operation.  If any of the regulators cannot be
4770  * acquired then any regulators that were allocated will be freed
4771  * before returning to the caller.
4772  */
4773 int regulator_bulk_get(struct device *dev, int num_consumers,
4774 		       struct regulator_bulk_data *consumers)
4775 {
4776 	int i;
4777 	int ret;
4778 
4779 	for (i = 0; i < num_consumers; i++)
4780 		consumers[i].consumer = NULL;
4781 
4782 	for (i = 0; i < num_consumers; i++) {
4783 		consumers[i].consumer = regulator_get(dev,
4784 						      consumers[i].supply);
4785 		if (IS_ERR(consumers[i].consumer)) {
4786 			ret = PTR_ERR(consumers[i].consumer);
4787 			consumers[i].consumer = NULL;
4788 			goto err;
4789 		}
4790 	}
4791 
4792 	return 0;
4793 
4794 err:
4795 	if (ret != -EPROBE_DEFER)
4796 		dev_err(dev, "Failed to get supply '%s': %pe\n",
4797 			consumers[i].supply, ERR_PTR(ret));
4798 	else
4799 		dev_dbg(dev, "Failed to get supply '%s', deferring\n",
4800 			consumers[i].supply);
4801 
4802 	while (--i >= 0)
4803 		regulator_put(consumers[i].consumer);
4804 
4805 	return ret;
4806 }
4807 EXPORT_SYMBOL_GPL(regulator_bulk_get);
4808 
4809 static void regulator_bulk_enable_async(void *data, async_cookie_t cookie)
4810 {
4811 	struct regulator_bulk_data *bulk = data;
4812 
4813 	bulk->ret = regulator_enable(bulk->consumer);
4814 }
4815 
4816 /**
4817  * regulator_bulk_enable - enable multiple regulator consumers
4818  *
4819  * @num_consumers: Number of consumers
4820  * @consumers:     Consumer data; clients are stored here.
4821  * @return         0 on success, an errno on failure
4822  *
4823  * This convenience API allows consumers to enable multiple regulator
4824  * clients in a single API call.  If any consumers cannot be enabled
4825  * then any others that were enabled will be disabled again prior to
4826  * return.
4827  */
4828 int regulator_bulk_enable(int num_consumers,
4829 			  struct regulator_bulk_data *consumers)
4830 {
4831 	ASYNC_DOMAIN_EXCLUSIVE(async_domain);
4832 	int i;
4833 	int ret = 0;
4834 
4835 	for (i = 0; i < num_consumers; i++) {
4836 		async_schedule_domain(regulator_bulk_enable_async,
4837 				      &consumers[i], &async_domain);
4838 	}
4839 
4840 	async_synchronize_full_domain(&async_domain);
4841 
4842 	/* If any consumer failed we need to unwind any that succeeded */
4843 	for (i = 0; i < num_consumers; i++) {
4844 		if (consumers[i].ret != 0) {
4845 			ret = consumers[i].ret;
4846 			goto err;
4847 		}
4848 	}
4849 
4850 	return 0;
4851 
4852 err:
4853 	for (i = 0; i < num_consumers; i++) {
4854 		if (consumers[i].ret < 0)
4855 			pr_err("Failed to enable %s: %pe\n", consumers[i].supply,
4856 			       ERR_PTR(consumers[i].ret));
4857 		else
4858 			regulator_disable(consumers[i].consumer);
4859 	}
4860 
4861 	return ret;
4862 }
4863 EXPORT_SYMBOL_GPL(regulator_bulk_enable);
4864 
4865 /**
4866  * regulator_bulk_disable - disable multiple regulator consumers
4867  *
4868  * @num_consumers: Number of consumers
4869  * @consumers:     Consumer data; clients are stored here.
4870  * @return         0 on success, an errno on failure
4871  *
4872  * This convenience API allows consumers to disable multiple regulator
4873  * clients in a single API call.  If any consumers cannot be disabled
4874  * then any others that were disabled will be enabled again prior to
4875  * return.
4876  */
4877 int regulator_bulk_disable(int num_consumers,
4878 			   struct regulator_bulk_data *consumers)
4879 {
4880 	int i;
4881 	int ret, r;
4882 
4883 	for (i = num_consumers - 1; i >= 0; --i) {
4884 		ret = regulator_disable(consumers[i].consumer);
4885 		if (ret != 0)
4886 			goto err;
4887 	}
4888 
4889 	return 0;
4890 
4891 err:
4892 	pr_err("Failed to disable %s: %pe\n", consumers[i].supply, ERR_PTR(ret));
4893 	for (++i; i < num_consumers; ++i) {
4894 		r = regulator_enable(consumers[i].consumer);
4895 		if (r != 0)
4896 			pr_err("Failed to re-enable %s: %pe\n",
4897 			       consumers[i].supply, ERR_PTR(r));
4898 	}
4899 
4900 	return ret;
4901 }
4902 EXPORT_SYMBOL_GPL(regulator_bulk_disable);
4903 
4904 /**
4905  * regulator_bulk_force_disable - force disable multiple regulator consumers
4906  *
4907  * @num_consumers: Number of consumers
4908  * @consumers:     Consumer data; clients are stored here.
4909  * @return         0 on success, an errno on failure
4910  *
4911  * This convenience API allows consumers to forcibly disable multiple regulator
4912  * clients in a single API call.
4913  * NOTE: This should be used for situations when device damage will
4914  * likely occur if the regulators are not disabled (e.g. over temp).
4915  * Although regulator_force_disable function call for some consumers can
4916  * return error numbers, the function is called for all consumers.
4917  */
4918 int regulator_bulk_force_disable(int num_consumers,
4919 			   struct regulator_bulk_data *consumers)
4920 {
4921 	int i;
4922 	int ret = 0;
4923 
4924 	for (i = 0; i < num_consumers; i++) {
4925 		consumers[i].ret =
4926 			    regulator_force_disable(consumers[i].consumer);
4927 
4928 		/* Store first error for reporting */
4929 		if (consumers[i].ret && !ret)
4930 			ret = consumers[i].ret;
4931 	}
4932 
4933 	return ret;
4934 }
4935 EXPORT_SYMBOL_GPL(regulator_bulk_force_disable);
4936 
4937 /**
4938  * regulator_bulk_free - free multiple regulator consumers
4939  *
4940  * @num_consumers: Number of consumers
4941  * @consumers:     Consumer data; clients are stored here.
4942  *
4943  * This convenience API allows consumers to free multiple regulator
4944  * clients in a single API call.
4945  */
4946 void regulator_bulk_free(int num_consumers,
4947 			 struct regulator_bulk_data *consumers)
4948 {
4949 	int i;
4950 
4951 	for (i = 0; i < num_consumers; i++) {
4952 		regulator_put(consumers[i].consumer);
4953 		consumers[i].consumer = NULL;
4954 	}
4955 }
4956 EXPORT_SYMBOL_GPL(regulator_bulk_free);
4957 
4958 /**
4959  * regulator_notifier_call_chain - call regulator event notifier
4960  * @rdev: regulator source
4961  * @event: notifier block
4962  * @data: callback-specific data.
4963  *
4964  * Called by regulator drivers to notify clients a regulator event has
4965  * occurred.
4966  */
4967 int regulator_notifier_call_chain(struct regulator_dev *rdev,
4968 				  unsigned long event, void *data)
4969 {
4970 	_notifier_call_chain(rdev, event, data);
4971 	return NOTIFY_DONE;
4972 
4973 }
4974 EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
4975 
4976 /**
4977  * regulator_mode_to_status - convert a regulator mode into a status
4978  *
4979  * @mode: Mode to convert
4980  *
4981  * Convert a regulator mode into a status.
4982  */
4983 int regulator_mode_to_status(unsigned int mode)
4984 {
4985 	switch (mode) {
4986 	case REGULATOR_MODE_FAST:
4987 		return REGULATOR_STATUS_FAST;
4988 	case REGULATOR_MODE_NORMAL:
4989 		return REGULATOR_STATUS_NORMAL;
4990 	case REGULATOR_MODE_IDLE:
4991 		return REGULATOR_STATUS_IDLE;
4992 	case REGULATOR_MODE_STANDBY:
4993 		return REGULATOR_STATUS_STANDBY;
4994 	default:
4995 		return REGULATOR_STATUS_UNDEFINED;
4996 	}
4997 }
4998 EXPORT_SYMBOL_GPL(regulator_mode_to_status);
4999 
5000 static struct attribute *regulator_dev_attrs[] = {
5001 	&dev_attr_name.attr,
5002 	&dev_attr_num_users.attr,
5003 	&dev_attr_type.attr,
5004 	&dev_attr_microvolts.attr,
5005 	&dev_attr_microamps.attr,
5006 	&dev_attr_opmode.attr,
5007 	&dev_attr_state.attr,
5008 	&dev_attr_status.attr,
5009 	&dev_attr_bypass.attr,
5010 	&dev_attr_requested_microamps.attr,
5011 	&dev_attr_min_microvolts.attr,
5012 	&dev_attr_max_microvolts.attr,
5013 	&dev_attr_min_microamps.attr,
5014 	&dev_attr_max_microamps.attr,
5015 	&dev_attr_under_voltage.attr,
5016 	&dev_attr_over_current.attr,
5017 	&dev_attr_regulation_out.attr,
5018 	&dev_attr_fail.attr,
5019 	&dev_attr_over_temp.attr,
5020 	&dev_attr_under_voltage_warn.attr,
5021 	&dev_attr_over_current_warn.attr,
5022 	&dev_attr_over_voltage_warn.attr,
5023 	&dev_attr_over_temp_warn.attr,
5024 	&dev_attr_suspend_standby_state.attr,
5025 	&dev_attr_suspend_mem_state.attr,
5026 	&dev_attr_suspend_disk_state.attr,
5027 	&dev_attr_suspend_standby_microvolts.attr,
5028 	&dev_attr_suspend_mem_microvolts.attr,
5029 	&dev_attr_suspend_disk_microvolts.attr,
5030 	&dev_attr_suspend_standby_mode.attr,
5031 	&dev_attr_suspend_mem_mode.attr,
5032 	&dev_attr_suspend_disk_mode.attr,
5033 	NULL
5034 };
5035 
5036 /*
5037  * To avoid cluttering sysfs (and memory) with useless state, only
5038  * create attributes that can be meaningfully displayed.
5039  */
5040 static umode_t regulator_attr_is_visible(struct kobject *kobj,
5041 					 struct attribute *attr, int idx)
5042 {
5043 	struct device *dev = kobj_to_dev(kobj);
5044 	struct regulator_dev *rdev = dev_to_rdev(dev);
5045 	const struct regulator_ops *ops = rdev->desc->ops;
5046 	umode_t mode = attr->mode;
5047 
5048 	/* these three are always present */
5049 	if (attr == &dev_attr_name.attr ||
5050 	    attr == &dev_attr_num_users.attr ||
5051 	    attr == &dev_attr_type.attr)
5052 		return mode;
5053 
5054 	/* some attributes need specific methods to be displayed */
5055 	if (attr == &dev_attr_microvolts.attr) {
5056 		if ((ops->get_voltage && ops->get_voltage(rdev) >= 0) ||
5057 		    (ops->get_voltage_sel && ops->get_voltage_sel(rdev) >= 0) ||
5058 		    (ops->list_voltage && ops->list_voltage(rdev, 0) >= 0) ||
5059 		    (rdev->desc->fixed_uV && rdev->desc->n_voltages == 1))
5060 			return mode;
5061 		return 0;
5062 	}
5063 
5064 	if (attr == &dev_attr_microamps.attr)
5065 		return ops->get_current_limit ? mode : 0;
5066 
5067 	if (attr == &dev_attr_opmode.attr)
5068 		return ops->get_mode ? mode : 0;
5069 
5070 	if (attr == &dev_attr_state.attr)
5071 		return (rdev->ena_pin || ops->is_enabled) ? mode : 0;
5072 
5073 	if (attr == &dev_attr_status.attr)
5074 		return ops->get_status ? mode : 0;
5075 
5076 	if (attr == &dev_attr_bypass.attr)
5077 		return ops->get_bypass ? mode : 0;
5078 
5079 	if (attr == &dev_attr_under_voltage.attr ||
5080 	    attr == &dev_attr_over_current.attr ||
5081 	    attr == &dev_attr_regulation_out.attr ||
5082 	    attr == &dev_attr_fail.attr ||
5083 	    attr == &dev_attr_over_temp.attr ||
5084 	    attr == &dev_attr_under_voltage_warn.attr ||
5085 	    attr == &dev_attr_over_current_warn.attr ||
5086 	    attr == &dev_attr_over_voltage_warn.attr ||
5087 	    attr == &dev_attr_over_temp_warn.attr)
5088 		return ops->get_error_flags ? mode : 0;
5089 
5090 	/* constraints need specific supporting methods */
5091 	if (attr == &dev_attr_min_microvolts.attr ||
5092 	    attr == &dev_attr_max_microvolts.attr)
5093 		return (ops->set_voltage || ops->set_voltage_sel) ? mode : 0;
5094 
5095 	if (attr == &dev_attr_min_microamps.attr ||
5096 	    attr == &dev_attr_max_microamps.attr)
5097 		return ops->set_current_limit ? mode : 0;
5098 
5099 	if (attr == &dev_attr_suspend_standby_state.attr ||
5100 	    attr == &dev_attr_suspend_mem_state.attr ||
5101 	    attr == &dev_attr_suspend_disk_state.attr)
5102 		return mode;
5103 
5104 	if (attr == &dev_attr_suspend_standby_microvolts.attr ||
5105 	    attr == &dev_attr_suspend_mem_microvolts.attr ||
5106 	    attr == &dev_attr_suspend_disk_microvolts.attr)
5107 		return ops->set_suspend_voltage ? mode : 0;
5108 
5109 	if (attr == &dev_attr_suspend_standby_mode.attr ||
5110 	    attr == &dev_attr_suspend_mem_mode.attr ||
5111 	    attr == &dev_attr_suspend_disk_mode.attr)
5112 		return ops->set_suspend_mode ? mode : 0;
5113 
5114 	return mode;
5115 }
5116 
5117 static const struct attribute_group regulator_dev_group = {
5118 	.attrs = regulator_dev_attrs,
5119 	.is_visible = regulator_attr_is_visible,
5120 };
5121 
5122 static const struct attribute_group *regulator_dev_groups[] = {
5123 	&regulator_dev_group,
5124 	NULL
5125 };
5126 
5127 static void regulator_dev_release(struct device *dev)
5128 {
5129 	struct regulator_dev *rdev = dev_get_drvdata(dev);
5130 
5131 	kfree(rdev->constraints);
5132 	of_node_put(rdev->dev.of_node);
5133 	kfree(rdev);
5134 }
5135 
5136 static void rdev_init_debugfs(struct regulator_dev *rdev)
5137 {
5138 	struct device *parent = rdev->dev.parent;
5139 	const char *rname = rdev_get_name(rdev);
5140 	char name[NAME_MAX];
5141 
5142 	/* Avoid duplicate debugfs directory names */
5143 	if (parent && rname == rdev->desc->name) {
5144 		snprintf(name, sizeof(name), "%s-%s", dev_name(parent),
5145 			 rname);
5146 		rname = name;
5147 	}
5148 
5149 	rdev->debugfs = debugfs_create_dir(rname, debugfs_root);
5150 	if (!rdev->debugfs) {
5151 		rdev_warn(rdev, "Failed to create debugfs directory\n");
5152 		return;
5153 	}
5154 
5155 	debugfs_create_u32("use_count", 0444, rdev->debugfs,
5156 			   &rdev->use_count);
5157 	debugfs_create_u32("open_count", 0444, rdev->debugfs,
5158 			   &rdev->open_count);
5159 	debugfs_create_u32("bypass_count", 0444, rdev->debugfs,
5160 			   &rdev->bypass_count);
5161 }
5162 
5163 static int regulator_register_resolve_supply(struct device *dev, void *data)
5164 {
5165 	struct regulator_dev *rdev = dev_to_rdev(dev);
5166 
5167 	if (regulator_resolve_supply(rdev))
5168 		rdev_dbg(rdev, "unable to resolve supply\n");
5169 
5170 	return 0;
5171 }
5172 
5173 int regulator_coupler_register(struct regulator_coupler *coupler)
5174 {
5175 	mutex_lock(&regulator_list_mutex);
5176 	list_add_tail(&coupler->list, &regulator_coupler_list);
5177 	mutex_unlock(&regulator_list_mutex);
5178 
5179 	return 0;
5180 }
5181 
5182 static struct regulator_coupler *
5183 regulator_find_coupler(struct regulator_dev *rdev)
5184 {
5185 	struct regulator_coupler *coupler;
5186 	int err;
5187 
5188 	/*
5189 	 * Note that regulators are appended to the list and the generic
5190 	 * coupler is registered first, hence it will be attached at last
5191 	 * if nobody cared.
5192 	 */
5193 	list_for_each_entry_reverse(coupler, &regulator_coupler_list, list) {
5194 		err = coupler->attach_regulator(coupler, rdev);
5195 		if (!err) {
5196 			if (!coupler->balance_voltage &&
5197 			    rdev->coupling_desc.n_coupled > 2)
5198 				goto err_unsupported;
5199 
5200 			return coupler;
5201 		}
5202 
5203 		if (err < 0)
5204 			return ERR_PTR(err);
5205 
5206 		if (err == 1)
5207 			continue;
5208 
5209 		break;
5210 	}
5211 
5212 	return ERR_PTR(-EINVAL);
5213 
5214 err_unsupported:
5215 	if (coupler->detach_regulator)
5216 		coupler->detach_regulator(coupler, rdev);
5217 
5218 	rdev_err(rdev,
5219 		"Voltage balancing for multiple regulator couples is unimplemented\n");
5220 
5221 	return ERR_PTR(-EPERM);
5222 }
5223 
5224 static void regulator_resolve_coupling(struct regulator_dev *rdev)
5225 {
5226 	struct regulator_coupler *coupler = rdev->coupling_desc.coupler;
5227 	struct coupling_desc *c_desc = &rdev->coupling_desc;
5228 	int n_coupled = c_desc->n_coupled;
5229 	struct regulator_dev *c_rdev;
5230 	int i;
5231 
5232 	for (i = 1; i < n_coupled; i++) {
5233 		/* already resolved */
5234 		if (c_desc->coupled_rdevs[i])
5235 			continue;
5236 
5237 		c_rdev = of_parse_coupled_regulator(rdev, i - 1);
5238 
5239 		if (!c_rdev)
5240 			continue;
5241 
5242 		if (c_rdev->coupling_desc.coupler != coupler) {
5243 			rdev_err(rdev, "coupler mismatch with %s\n",
5244 				 rdev_get_name(c_rdev));
5245 			return;
5246 		}
5247 
5248 		c_desc->coupled_rdevs[i] = c_rdev;
5249 		c_desc->n_resolved++;
5250 
5251 		regulator_resolve_coupling(c_rdev);
5252 	}
5253 }
5254 
5255 static void regulator_remove_coupling(struct regulator_dev *rdev)
5256 {
5257 	struct regulator_coupler *coupler = rdev->coupling_desc.coupler;
5258 	struct coupling_desc *__c_desc, *c_desc = &rdev->coupling_desc;
5259 	struct regulator_dev *__c_rdev, *c_rdev;
5260 	unsigned int __n_coupled, n_coupled;
5261 	int i, k;
5262 	int err;
5263 
5264 	n_coupled = c_desc->n_coupled;
5265 
5266 	for (i = 1; i < n_coupled; i++) {
5267 		c_rdev = c_desc->coupled_rdevs[i];
5268 
5269 		if (!c_rdev)
5270 			continue;
5271 
5272 		regulator_lock(c_rdev);
5273 
5274 		__c_desc = &c_rdev->coupling_desc;
5275 		__n_coupled = __c_desc->n_coupled;
5276 
5277 		for (k = 1; k < __n_coupled; k++) {
5278 			__c_rdev = __c_desc->coupled_rdevs[k];
5279 
5280 			if (__c_rdev == rdev) {
5281 				__c_desc->coupled_rdevs[k] = NULL;
5282 				__c_desc->n_resolved--;
5283 				break;
5284 			}
5285 		}
5286 
5287 		regulator_unlock(c_rdev);
5288 
5289 		c_desc->coupled_rdevs[i] = NULL;
5290 		c_desc->n_resolved--;
5291 	}
5292 
5293 	if (coupler && coupler->detach_regulator) {
5294 		err = coupler->detach_regulator(coupler, rdev);
5295 		if (err)
5296 			rdev_err(rdev, "failed to detach from coupler: %pe\n",
5297 				 ERR_PTR(err));
5298 	}
5299 
5300 	kfree(rdev->coupling_desc.coupled_rdevs);
5301 	rdev->coupling_desc.coupled_rdevs = NULL;
5302 }
5303 
5304 static int regulator_init_coupling(struct regulator_dev *rdev)
5305 {
5306 	struct regulator_dev **coupled;
5307 	int err, n_phandles;
5308 
5309 	if (!IS_ENABLED(CONFIG_OF))
5310 		n_phandles = 0;
5311 	else
5312 		n_phandles = of_get_n_coupled(rdev);
5313 
5314 	coupled = kcalloc(n_phandles + 1, sizeof(*coupled), GFP_KERNEL);
5315 	if (!coupled)
5316 		return -ENOMEM;
5317 
5318 	rdev->coupling_desc.coupled_rdevs = coupled;
5319 
5320 	/*
5321 	 * Every regulator should always have coupling descriptor filled with
5322 	 * at least pointer to itself.
5323 	 */
5324 	rdev->coupling_desc.coupled_rdevs[0] = rdev;
5325 	rdev->coupling_desc.n_coupled = n_phandles + 1;
5326 	rdev->coupling_desc.n_resolved++;
5327 
5328 	/* regulator isn't coupled */
5329 	if (n_phandles == 0)
5330 		return 0;
5331 
5332 	if (!of_check_coupling_data(rdev))
5333 		return -EPERM;
5334 
5335 	mutex_lock(&regulator_list_mutex);
5336 	rdev->coupling_desc.coupler = regulator_find_coupler(rdev);
5337 	mutex_unlock(&regulator_list_mutex);
5338 
5339 	if (IS_ERR(rdev->coupling_desc.coupler)) {
5340 		err = PTR_ERR(rdev->coupling_desc.coupler);
5341 		rdev_err(rdev, "failed to get coupler: %pe\n", ERR_PTR(err));
5342 		return err;
5343 	}
5344 
5345 	return 0;
5346 }
5347 
5348 static int generic_coupler_attach(struct regulator_coupler *coupler,
5349 				  struct regulator_dev *rdev)
5350 {
5351 	if (rdev->coupling_desc.n_coupled > 2) {
5352 		rdev_err(rdev,
5353 			 "Voltage balancing for multiple regulator couples is unimplemented\n");
5354 		return -EPERM;
5355 	}
5356 
5357 	if (!rdev->constraints->always_on) {
5358 		rdev_err(rdev,
5359 			 "Coupling of a non always-on regulator is unimplemented\n");
5360 		return -ENOTSUPP;
5361 	}
5362 
5363 	return 0;
5364 }
5365 
5366 static struct regulator_coupler generic_regulator_coupler = {
5367 	.attach_regulator = generic_coupler_attach,
5368 };
5369 
5370 /**
5371  * regulator_register - register regulator
5372  * @regulator_desc: regulator to register
5373  * @cfg: runtime configuration for regulator
5374  *
5375  * Called by regulator drivers to register a regulator.
5376  * Returns a valid pointer to struct regulator_dev on success
5377  * or an ERR_PTR() on error.
5378  */
5379 struct regulator_dev *
5380 regulator_register(const struct regulator_desc *regulator_desc,
5381 		   const struct regulator_config *cfg)
5382 {
5383 	const struct regulator_init_data *init_data;
5384 	struct regulator_config *config = NULL;
5385 	static atomic_t regulator_no = ATOMIC_INIT(-1);
5386 	struct regulator_dev *rdev;
5387 	bool dangling_cfg_gpiod = false;
5388 	bool dangling_of_gpiod = false;
5389 	struct device *dev;
5390 	int ret, i;
5391 
5392 	if (cfg == NULL)
5393 		return ERR_PTR(-EINVAL);
5394 	if (cfg->ena_gpiod)
5395 		dangling_cfg_gpiod = true;
5396 	if (regulator_desc == NULL) {
5397 		ret = -EINVAL;
5398 		goto rinse;
5399 	}
5400 
5401 	dev = cfg->dev;
5402 	WARN_ON(!dev);
5403 
5404 	if (regulator_desc->name == NULL || regulator_desc->ops == NULL) {
5405 		ret = -EINVAL;
5406 		goto rinse;
5407 	}
5408 
5409 	if (regulator_desc->type != REGULATOR_VOLTAGE &&
5410 	    regulator_desc->type != REGULATOR_CURRENT) {
5411 		ret = -EINVAL;
5412 		goto rinse;
5413 	}
5414 
5415 	/* Only one of each should be implemented */
5416 	WARN_ON(regulator_desc->ops->get_voltage &&
5417 		regulator_desc->ops->get_voltage_sel);
5418 	WARN_ON(regulator_desc->ops->set_voltage &&
5419 		regulator_desc->ops->set_voltage_sel);
5420 
5421 	/* If we're using selectors we must implement list_voltage. */
5422 	if (regulator_desc->ops->get_voltage_sel &&
5423 	    !regulator_desc->ops->list_voltage) {
5424 		ret = -EINVAL;
5425 		goto rinse;
5426 	}
5427 	if (regulator_desc->ops->set_voltage_sel &&
5428 	    !regulator_desc->ops->list_voltage) {
5429 		ret = -EINVAL;
5430 		goto rinse;
5431 	}
5432 
5433 	rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
5434 	if (rdev == NULL) {
5435 		ret = -ENOMEM;
5436 		goto rinse;
5437 	}
5438 	device_initialize(&rdev->dev);
5439 	spin_lock_init(&rdev->err_lock);
5440 
5441 	/*
5442 	 * Duplicate the config so the driver could override it after
5443 	 * parsing init data.
5444 	 */
5445 	config = kmemdup(cfg, sizeof(*cfg), GFP_KERNEL);
5446 	if (config == NULL) {
5447 		ret = -ENOMEM;
5448 		goto clean;
5449 	}
5450 
5451 	init_data = regulator_of_get_init_data(dev, regulator_desc, config,
5452 					       &rdev->dev.of_node);
5453 
5454 	/*
5455 	 * Sometimes not all resources are probed already so we need to take
5456 	 * that into account. This happens most the time if the ena_gpiod comes
5457 	 * from a gpio extender or something else.
5458 	 */
5459 	if (PTR_ERR(init_data) == -EPROBE_DEFER) {
5460 		ret = -EPROBE_DEFER;
5461 		goto clean;
5462 	}
5463 
5464 	/*
5465 	 * We need to keep track of any GPIO descriptor coming from the
5466 	 * device tree until we have handled it over to the core. If the
5467 	 * config that was passed in to this function DOES NOT contain
5468 	 * a descriptor, and the config after this call DOES contain
5469 	 * a descriptor, we definitely got one from parsing the device
5470 	 * tree.
5471 	 */
5472 	if (!cfg->ena_gpiod && config->ena_gpiod)
5473 		dangling_of_gpiod = true;
5474 	if (!init_data) {
5475 		init_data = config->init_data;
5476 		rdev->dev.of_node = of_node_get(config->of_node);
5477 	}
5478 
5479 	ww_mutex_init(&rdev->mutex, &regulator_ww_class);
5480 	rdev->reg_data = config->driver_data;
5481 	rdev->owner = regulator_desc->owner;
5482 	rdev->desc = regulator_desc;
5483 	if (config->regmap)
5484 		rdev->regmap = config->regmap;
5485 	else if (dev_get_regmap(dev, NULL))
5486 		rdev->regmap = dev_get_regmap(dev, NULL);
5487 	else if (dev->parent)
5488 		rdev->regmap = dev_get_regmap(dev->parent, NULL);
5489 	INIT_LIST_HEAD(&rdev->consumer_list);
5490 	INIT_LIST_HEAD(&rdev->list);
5491 	BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
5492 	INIT_DELAYED_WORK(&rdev->disable_work, regulator_disable_work);
5493 
5494 	/* preform any regulator specific init */
5495 	if (init_data && init_data->regulator_init) {
5496 		ret = init_data->regulator_init(rdev->reg_data);
5497 		if (ret < 0)
5498 			goto clean;
5499 	}
5500 
5501 	if (config->ena_gpiod) {
5502 		ret = regulator_ena_gpio_request(rdev, config);
5503 		if (ret != 0) {
5504 			rdev_err(rdev, "Failed to request enable GPIO: %pe\n",
5505 				 ERR_PTR(ret));
5506 			goto clean;
5507 		}
5508 		/* The regulator core took over the GPIO descriptor */
5509 		dangling_cfg_gpiod = false;
5510 		dangling_of_gpiod = false;
5511 	}
5512 
5513 	/* register with sysfs */
5514 	rdev->dev.class = &regulator_class;
5515 	rdev->dev.parent = dev;
5516 	dev_set_name(&rdev->dev, "regulator.%lu",
5517 		    (unsigned long) atomic_inc_return(&regulator_no));
5518 	dev_set_drvdata(&rdev->dev, rdev);
5519 
5520 	/* set regulator constraints */
5521 	if (init_data)
5522 		rdev->constraints = kmemdup(&init_data->constraints,
5523 					    sizeof(*rdev->constraints),
5524 					    GFP_KERNEL);
5525 	else
5526 		rdev->constraints = kzalloc(sizeof(*rdev->constraints),
5527 					    GFP_KERNEL);
5528 	if (!rdev->constraints) {
5529 		ret = -ENOMEM;
5530 		goto wash;
5531 	}
5532 
5533 	if (init_data && init_data->supply_regulator)
5534 		rdev->supply_name = init_data->supply_regulator;
5535 	else if (regulator_desc->supply_name)
5536 		rdev->supply_name = regulator_desc->supply_name;
5537 
5538 	ret = set_machine_constraints(rdev);
5539 	if (ret == -EPROBE_DEFER) {
5540 		/* Regulator might be in bypass mode and so needs its supply
5541 		 * to set the constraints
5542 		 */
5543 		/* FIXME: this currently triggers a chicken-and-egg problem
5544 		 * when creating -SUPPLY symlink in sysfs to a regulator
5545 		 * that is just being created
5546 		 */
5547 		rdev_dbg(rdev, "will resolve supply early: %s\n",
5548 			 rdev->supply_name);
5549 		ret = regulator_resolve_supply(rdev);
5550 		if (!ret)
5551 			ret = set_machine_constraints(rdev);
5552 		else
5553 			rdev_dbg(rdev, "unable to resolve supply early: %pe\n",
5554 				 ERR_PTR(ret));
5555 	}
5556 	if (ret < 0)
5557 		goto wash;
5558 
5559 	ret = regulator_init_coupling(rdev);
5560 	if (ret < 0)
5561 		goto wash;
5562 
5563 	/* add consumers devices */
5564 	if (init_data) {
5565 		for (i = 0; i < init_data->num_consumer_supplies; i++) {
5566 			ret = set_consumer_device_supply(rdev,
5567 				init_data->consumer_supplies[i].dev_name,
5568 				init_data->consumer_supplies[i].supply);
5569 			if (ret < 0) {
5570 				dev_err(dev, "Failed to set supply %s\n",
5571 					init_data->consumer_supplies[i].supply);
5572 				goto unset_supplies;
5573 			}
5574 		}
5575 	}
5576 
5577 	if (!rdev->desc->ops->get_voltage &&
5578 	    !rdev->desc->ops->list_voltage &&
5579 	    !rdev->desc->fixed_uV)
5580 		rdev->is_switch = true;
5581 
5582 	ret = device_add(&rdev->dev);
5583 	if (ret != 0)
5584 		goto unset_supplies;
5585 
5586 	rdev_init_debugfs(rdev);
5587 
5588 	/* try to resolve regulators coupling since a new one was registered */
5589 	mutex_lock(&regulator_list_mutex);
5590 	regulator_resolve_coupling(rdev);
5591 	mutex_unlock(&regulator_list_mutex);
5592 
5593 	/* try to resolve regulators supply since a new one was registered */
5594 	class_for_each_device(&regulator_class, NULL, NULL,
5595 			      regulator_register_resolve_supply);
5596 	kfree(config);
5597 	return rdev;
5598 
5599 unset_supplies:
5600 	mutex_lock(&regulator_list_mutex);
5601 	unset_regulator_supplies(rdev);
5602 	regulator_remove_coupling(rdev);
5603 	mutex_unlock(&regulator_list_mutex);
5604 wash:
5605 	kfree(rdev->coupling_desc.coupled_rdevs);
5606 	mutex_lock(&regulator_list_mutex);
5607 	regulator_ena_gpio_free(rdev);
5608 	mutex_unlock(&regulator_list_mutex);
5609 clean:
5610 	if (dangling_of_gpiod)
5611 		gpiod_put(config->ena_gpiod);
5612 	kfree(config);
5613 	put_device(&rdev->dev);
5614 rinse:
5615 	if (dangling_cfg_gpiod)
5616 		gpiod_put(cfg->ena_gpiod);
5617 	return ERR_PTR(ret);
5618 }
5619 EXPORT_SYMBOL_GPL(regulator_register);
5620 
5621 /**
5622  * regulator_unregister - unregister regulator
5623  * @rdev: regulator to unregister
5624  *
5625  * Called by regulator drivers to unregister a regulator.
5626  */
5627 void regulator_unregister(struct regulator_dev *rdev)
5628 {
5629 	if (rdev == NULL)
5630 		return;
5631 
5632 	if (rdev->supply) {
5633 		while (rdev->use_count--)
5634 			regulator_disable(rdev->supply);
5635 		regulator_put(rdev->supply);
5636 	}
5637 
5638 	flush_work(&rdev->disable_work.work);
5639 
5640 	mutex_lock(&regulator_list_mutex);
5641 
5642 	debugfs_remove_recursive(rdev->debugfs);
5643 	WARN_ON(rdev->open_count);
5644 	regulator_remove_coupling(rdev);
5645 	unset_regulator_supplies(rdev);
5646 	list_del(&rdev->list);
5647 	regulator_ena_gpio_free(rdev);
5648 	device_unregister(&rdev->dev);
5649 
5650 	mutex_unlock(&regulator_list_mutex);
5651 }
5652 EXPORT_SYMBOL_GPL(regulator_unregister);
5653 
5654 #ifdef CONFIG_SUSPEND
5655 /**
5656  * regulator_suspend - prepare regulators for system wide suspend
5657  * @dev: ``&struct device`` pointer that is passed to _regulator_suspend()
5658  *
5659  * Configure each regulator with it's suspend operating parameters for state.
5660  */
5661 static int regulator_suspend(struct device *dev)
5662 {
5663 	struct regulator_dev *rdev = dev_to_rdev(dev);
5664 	suspend_state_t state = pm_suspend_target_state;
5665 	int ret;
5666 	const struct regulator_state *rstate;
5667 
5668 	rstate = regulator_get_suspend_state_check(rdev, state);
5669 	if (!rstate)
5670 		return 0;
5671 
5672 	regulator_lock(rdev);
5673 	ret = __suspend_set_state(rdev, rstate);
5674 	regulator_unlock(rdev);
5675 
5676 	return ret;
5677 }
5678 
5679 static int regulator_resume(struct device *dev)
5680 {
5681 	suspend_state_t state = pm_suspend_target_state;
5682 	struct regulator_dev *rdev = dev_to_rdev(dev);
5683 	struct regulator_state *rstate;
5684 	int ret = 0;
5685 
5686 	rstate = regulator_get_suspend_state(rdev, state);
5687 	if (rstate == NULL)
5688 		return 0;
5689 
5690 	/* Avoid grabbing the lock if we don't need to */
5691 	if (!rdev->desc->ops->resume)
5692 		return 0;
5693 
5694 	regulator_lock(rdev);
5695 
5696 	if (rstate->enabled == ENABLE_IN_SUSPEND ||
5697 	    rstate->enabled == DISABLE_IN_SUSPEND)
5698 		ret = rdev->desc->ops->resume(rdev);
5699 
5700 	regulator_unlock(rdev);
5701 
5702 	return ret;
5703 }
5704 #else /* !CONFIG_SUSPEND */
5705 
5706 #define regulator_suspend	NULL
5707 #define regulator_resume	NULL
5708 
5709 #endif /* !CONFIG_SUSPEND */
5710 
5711 #ifdef CONFIG_PM
5712 static const struct dev_pm_ops __maybe_unused regulator_pm_ops = {
5713 	.suspend	= regulator_suspend,
5714 	.resume		= regulator_resume,
5715 };
5716 #endif
5717 
5718 struct class regulator_class = {
5719 	.name = "regulator",
5720 	.dev_release = regulator_dev_release,
5721 	.dev_groups = regulator_dev_groups,
5722 #ifdef CONFIG_PM
5723 	.pm = &regulator_pm_ops,
5724 #endif
5725 };
5726 /**
5727  * regulator_has_full_constraints - the system has fully specified constraints
5728  *
5729  * Calling this function will cause the regulator API to disable all
5730  * regulators which have a zero use count and don't have an always_on
5731  * constraint in a late_initcall.
5732  *
5733  * The intention is that this will become the default behaviour in a
5734  * future kernel release so users are encouraged to use this facility
5735  * now.
5736  */
5737 void regulator_has_full_constraints(void)
5738 {
5739 	has_full_constraints = 1;
5740 }
5741 EXPORT_SYMBOL_GPL(regulator_has_full_constraints);
5742 
5743 /**
5744  * rdev_get_drvdata - get rdev regulator driver data
5745  * @rdev: regulator
5746  *
5747  * Get rdev regulator driver private data. This call can be used in the
5748  * regulator driver context.
5749  */
5750 void *rdev_get_drvdata(struct regulator_dev *rdev)
5751 {
5752 	return rdev->reg_data;
5753 }
5754 EXPORT_SYMBOL_GPL(rdev_get_drvdata);
5755 
5756 /**
5757  * regulator_get_drvdata - get regulator driver data
5758  * @regulator: regulator
5759  *
5760  * Get regulator driver private data. This call can be used in the consumer
5761  * driver context when non API regulator specific functions need to be called.
5762  */
5763 void *regulator_get_drvdata(struct regulator *regulator)
5764 {
5765 	return regulator->rdev->reg_data;
5766 }
5767 EXPORT_SYMBOL_GPL(regulator_get_drvdata);
5768 
5769 /**
5770  * regulator_set_drvdata - set regulator driver data
5771  * @regulator: regulator
5772  * @data: data
5773  */
5774 void regulator_set_drvdata(struct regulator *regulator, void *data)
5775 {
5776 	regulator->rdev->reg_data = data;
5777 }
5778 EXPORT_SYMBOL_GPL(regulator_set_drvdata);
5779 
5780 /**
5781  * rdev_get_id - get regulator ID
5782  * @rdev: regulator
5783  */
5784 int rdev_get_id(struct regulator_dev *rdev)
5785 {
5786 	return rdev->desc->id;
5787 }
5788 EXPORT_SYMBOL_GPL(rdev_get_id);
5789 
5790 struct device *rdev_get_dev(struct regulator_dev *rdev)
5791 {
5792 	return &rdev->dev;
5793 }
5794 EXPORT_SYMBOL_GPL(rdev_get_dev);
5795 
5796 struct regmap *rdev_get_regmap(struct regulator_dev *rdev)
5797 {
5798 	return rdev->regmap;
5799 }
5800 EXPORT_SYMBOL_GPL(rdev_get_regmap);
5801 
5802 void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
5803 {
5804 	return reg_init_data->driver_data;
5805 }
5806 EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
5807 
5808 #ifdef CONFIG_DEBUG_FS
5809 static int supply_map_show(struct seq_file *sf, void *data)
5810 {
5811 	struct regulator_map *map;
5812 
5813 	list_for_each_entry(map, &regulator_map_list, list) {
5814 		seq_printf(sf, "%s -> %s.%s\n",
5815 				rdev_get_name(map->regulator), map->dev_name,
5816 				map->supply);
5817 	}
5818 
5819 	return 0;
5820 }
5821 DEFINE_SHOW_ATTRIBUTE(supply_map);
5822 
5823 struct summary_data {
5824 	struct seq_file *s;
5825 	struct regulator_dev *parent;
5826 	int level;
5827 };
5828 
5829 static void regulator_summary_show_subtree(struct seq_file *s,
5830 					   struct regulator_dev *rdev,
5831 					   int level);
5832 
5833 static int regulator_summary_show_children(struct device *dev, void *data)
5834 {
5835 	struct regulator_dev *rdev = dev_to_rdev(dev);
5836 	struct summary_data *summary_data = data;
5837 
5838 	if (rdev->supply && rdev->supply->rdev == summary_data->parent)
5839 		regulator_summary_show_subtree(summary_data->s, rdev,
5840 					       summary_data->level + 1);
5841 
5842 	return 0;
5843 }
5844 
5845 static void regulator_summary_show_subtree(struct seq_file *s,
5846 					   struct regulator_dev *rdev,
5847 					   int level)
5848 {
5849 	struct regulation_constraints *c;
5850 	struct regulator *consumer;
5851 	struct summary_data summary_data;
5852 	unsigned int opmode;
5853 
5854 	if (!rdev)
5855 		return;
5856 
5857 	opmode = _regulator_get_mode_unlocked(rdev);
5858 	seq_printf(s, "%*s%-*s %3d %4d %6d %7s ",
5859 		   level * 3 + 1, "",
5860 		   30 - level * 3, rdev_get_name(rdev),
5861 		   rdev->use_count, rdev->open_count, rdev->bypass_count,
5862 		   regulator_opmode_to_str(opmode));
5863 
5864 	seq_printf(s, "%5dmV ", regulator_get_voltage_rdev(rdev) / 1000);
5865 	seq_printf(s, "%5dmA ",
5866 		   _regulator_get_current_limit_unlocked(rdev) / 1000);
5867 
5868 	c = rdev->constraints;
5869 	if (c) {
5870 		switch (rdev->desc->type) {
5871 		case REGULATOR_VOLTAGE:
5872 			seq_printf(s, "%5dmV %5dmV ",
5873 				   c->min_uV / 1000, c->max_uV / 1000);
5874 			break;
5875 		case REGULATOR_CURRENT:
5876 			seq_printf(s, "%5dmA %5dmA ",
5877 				   c->min_uA / 1000, c->max_uA / 1000);
5878 			break;
5879 		}
5880 	}
5881 
5882 	seq_puts(s, "\n");
5883 
5884 	list_for_each_entry(consumer, &rdev->consumer_list, list) {
5885 		if (consumer->dev && consumer->dev->class == &regulator_class)
5886 			continue;
5887 
5888 		seq_printf(s, "%*s%-*s ",
5889 			   (level + 1) * 3 + 1, "",
5890 			   30 - (level + 1) * 3,
5891 			   consumer->supply_name ? consumer->supply_name :
5892 			   consumer->dev ? dev_name(consumer->dev) : "deviceless");
5893 
5894 		switch (rdev->desc->type) {
5895 		case REGULATOR_VOLTAGE:
5896 			seq_printf(s, "%3d %33dmA%c%5dmV %5dmV",
5897 				   consumer->enable_count,
5898 				   consumer->uA_load / 1000,
5899 				   consumer->uA_load && !consumer->enable_count ?
5900 				   '*' : ' ',
5901 				   consumer->voltage[PM_SUSPEND_ON].min_uV / 1000,
5902 				   consumer->voltage[PM_SUSPEND_ON].max_uV / 1000);
5903 			break;
5904 		case REGULATOR_CURRENT:
5905 			break;
5906 		}
5907 
5908 		seq_puts(s, "\n");
5909 	}
5910 
5911 	summary_data.s = s;
5912 	summary_data.level = level;
5913 	summary_data.parent = rdev;
5914 
5915 	class_for_each_device(&regulator_class, NULL, &summary_data,
5916 			      regulator_summary_show_children);
5917 }
5918 
5919 struct summary_lock_data {
5920 	struct ww_acquire_ctx *ww_ctx;
5921 	struct regulator_dev **new_contended_rdev;
5922 	struct regulator_dev **old_contended_rdev;
5923 };
5924 
5925 static int regulator_summary_lock_one(struct device *dev, void *data)
5926 {
5927 	struct regulator_dev *rdev = dev_to_rdev(dev);
5928 	struct summary_lock_data *lock_data = data;
5929 	int ret = 0;
5930 
5931 	if (rdev != *lock_data->old_contended_rdev) {
5932 		ret = regulator_lock_nested(rdev, lock_data->ww_ctx);
5933 
5934 		if (ret == -EDEADLK)
5935 			*lock_data->new_contended_rdev = rdev;
5936 		else
5937 			WARN_ON_ONCE(ret);
5938 	} else {
5939 		*lock_data->old_contended_rdev = NULL;
5940 	}
5941 
5942 	return ret;
5943 }
5944 
5945 static int regulator_summary_unlock_one(struct device *dev, void *data)
5946 {
5947 	struct regulator_dev *rdev = dev_to_rdev(dev);
5948 	struct summary_lock_data *lock_data = data;
5949 
5950 	if (lock_data) {
5951 		if (rdev == *lock_data->new_contended_rdev)
5952 			return -EDEADLK;
5953 	}
5954 
5955 	regulator_unlock(rdev);
5956 
5957 	return 0;
5958 }
5959 
5960 static int regulator_summary_lock_all(struct ww_acquire_ctx *ww_ctx,
5961 				      struct regulator_dev **new_contended_rdev,
5962 				      struct regulator_dev **old_contended_rdev)
5963 {
5964 	struct summary_lock_data lock_data;
5965 	int ret;
5966 
5967 	lock_data.ww_ctx = ww_ctx;
5968 	lock_data.new_contended_rdev = new_contended_rdev;
5969 	lock_data.old_contended_rdev = old_contended_rdev;
5970 
5971 	ret = class_for_each_device(&regulator_class, NULL, &lock_data,
5972 				    regulator_summary_lock_one);
5973 	if (ret)
5974 		class_for_each_device(&regulator_class, NULL, &lock_data,
5975 				      regulator_summary_unlock_one);
5976 
5977 	return ret;
5978 }
5979 
5980 static void regulator_summary_lock(struct ww_acquire_ctx *ww_ctx)
5981 {
5982 	struct regulator_dev *new_contended_rdev = NULL;
5983 	struct regulator_dev *old_contended_rdev = NULL;
5984 	int err;
5985 
5986 	mutex_lock(&regulator_list_mutex);
5987 
5988 	ww_acquire_init(ww_ctx, &regulator_ww_class);
5989 
5990 	do {
5991 		if (new_contended_rdev) {
5992 			ww_mutex_lock_slow(&new_contended_rdev->mutex, ww_ctx);
5993 			old_contended_rdev = new_contended_rdev;
5994 			old_contended_rdev->ref_cnt++;
5995 		}
5996 
5997 		err = regulator_summary_lock_all(ww_ctx,
5998 						 &new_contended_rdev,
5999 						 &old_contended_rdev);
6000 
6001 		if (old_contended_rdev)
6002 			regulator_unlock(old_contended_rdev);
6003 
6004 	} while (err == -EDEADLK);
6005 
6006 	ww_acquire_done(ww_ctx);
6007 }
6008 
6009 static void regulator_summary_unlock(struct ww_acquire_ctx *ww_ctx)
6010 {
6011 	class_for_each_device(&regulator_class, NULL, NULL,
6012 			      regulator_summary_unlock_one);
6013 	ww_acquire_fini(ww_ctx);
6014 
6015 	mutex_unlock(&regulator_list_mutex);
6016 }
6017 
6018 static int regulator_summary_show_roots(struct device *dev, void *data)
6019 {
6020 	struct regulator_dev *rdev = dev_to_rdev(dev);
6021 	struct seq_file *s = data;
6022 
6023 	if (!rdev->supply)
6024 		regulator_summary_show_subtree(s, rdev, 0);
6025 
6026 	return 0;
6027 }
6028 
6029 static int regulator_summary_show(struct seq_file *s, void *data)
6030 {
6031 	struct ww_acquire_ctx ww_ctx;
6032 
6033 	seq_puts(s, " regulator                      use open bypass  opmode voltage current     min     max\n");
6034 	seq_puts(s, "---------------------------------------------------------------------------------------\n");
6035 
6036 	regulator_summary_lock(&ww_ctx);
6037 
6038 	class_for_each_device(&regulator_class, NULL, s,
6039 			      regulator_summary_show_roots);
6040 
6041 	regulator_summary_unlock(&ww_ctx);
6042 
6043 	return 0;
6044 }
6045 DEFINE_SHOW_ATTRIBUTE(regulator_summary);
6046 #endif /* CONFIG_DEBUG_FS */
6047 
6048 static int __init regulator_init(void)
6049 {
6050 	int ret;
6051 
6052 	ret = class_register(&regulator_class);
6053 
6054 	debugfs_root = debugfs_create_dir("regulator", NULL);
6055 	if (!debugfs_root)
6056 		pr_warn("regulator: Failed to create debugfs directory\n");
6057 
6058 #ifdef CONFIG_DEBUG_FS
6059 	debugfs_create_file("supply_map", 0444, debugfs_root, NULL,
6060 			    &supply_map_fops);
6061 
6062 	debugfs_create_file("regulator_summary", 0444, debugfs_root,
6063 			    NULL, &regulator_summary_fops);
6064 #endif
6065 	regulator_dummy_init();
6066 
6067 	regulator_coupler_register(&generic_regulator_coupler);
6068 
6069 	return ret;
6070 }
6071 
6072 /* init early to allow our consumers to complete system booting */
6073 core_initcall(regulator_init);
6074 
6075 static int regulator_late_cleanup(struct device *dev, void *data)
6076 {
6077 	struct regulator_dev *rdev = dev_to_rdev(dev);
6078 	struct regulation_constraints *c = rdev->constraints;
6079 	int ret;
6080 
6081 	if (c && c->always_on)
6082 		return 0;
6083 
6084 	if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_STATUS))
6085 		return 0;
6086 
6087 	regulator_lock(rdev);
6088 
6089 	if (rdev->use_count)
6090 		goto unlock;
6091 
6092 	/* If reading the status failed, assume that it's off. */
6093 	if (_regulator_is_enabled(rdev) <= 0)
6094 		goto unlock;
6095 
6096 	if (have_full_constraints()) {
6097 		/* We log since this may kill the system if it goes
6098 		 * wrong.
6099 		 */
6100 		rdev_info(rdev, "disabling\n");
6101 		ret = _regulator_do_disable(rdev);
6102 		if (ret != 0)
6103 			rdev_err(rdev, "couldn't disable: %pe\n", ERR_PTR(ret));
6104 	} else {
6105 		/* The intention is that in future we will
6106 		 * assume that full constraints are provided
6107 		 * so warn even if we aren't going to do
6108 		 * anything here.
6109 		 */
6110 		rdev_warn(rdev, "incomplete constraints, leaving on\n");
6111 	}
6112 
6113 unlock:
6114 	regulator_unlock(rdev);
6115 
6116 	return 0;
6117 }
6118 
6119 static void regulator_init_complete_work_function(struct work_struct *work)
6120 {
6121 	/*
6122 	 * Regulators may had failed to resolve their input supplies
6123 	 * when were registered, either because the input supply was
6124 	 * not registered yet or because its parent device was not
6125 	 * bound yet. So attempt to resolve the input supplies for
6126 	 * pending regulators before trying to disable unused ones.
6127 	 */
6128 	class_for_each_device(&regulator_class, NULL, NULL,
6129 			      regulator_register_resolve_supply);
6130 
6131 	/* If we have a full configuration then disable any regulators
6132 	 * we have permission to change the status for and which are
6133 	 * not in use or always_on.  This is effectively the default
6134 	 * for DT and ACPI as they have full constraints.
6135 	 */
6136 	class_for_each_device(&regulator_class, NULL, NULL,
6137 			      regulator_late_cleanup);
6138 }
6139 
6140 static DECLARE_DELAYED_WORK(regulator_init_complete_work,
6141 			    regulator_init_complete_work_function);
6142 
6143 static int __init regulator_init_complete(void)
6144 {
6145 	/*
6146 	 * Since DT doesn't provide an idiomatic mechanism for
6147 	 * enabling full constraints and since it's much more natural
6148 	 * with DT to provide them just assume that a DT enabled
6149 	 * system has full constraints.
6150 	 */
6151 	if (of_have_populated_dt())
6152 		has_full_constraints = true;
6153 
6154 	/*
6155 	 * We punt completion for an arbitrary amount of time since
6156 	 * systems like distros will load many drivers from userspace
6157 	 * so consumers might not always be ready yet, this is
6158 	 * particularly an issue with laptops where this might bounce
6159 	 * the display off then on.  Ideally we'd get a notification
6160 	 * from userspace when this happens but we don't so just wait
6161 	 * a bit and hope we waited long enough.  It'd be better if
6162 	 * we'd only do this on systems that need it, and a kernel
6163 	 * command line option might be useful.
6164 	 */
6165 	schedule_delayed_work(&regulator_init_complete_work,
6166 			      msecs_to_jiffies(30000));
6167 
6168 	return 0;
6169 }
6170 late_initcall_sync(regulator_init_complete);
6171