xref: /openbmc/linux/drivers/regulator/core.c (revision 206e8c00752fbe9cc463184236ac64b2a532cda5)
1 /*
2  * core.c  --  Voltage/Current Regulator framework.
3  *
4  * Copyright 2007, 2008 Wolfson Microelectronics PLC.
5  * Copyright 2008 SlimLogic Ltd.
6  *
7  * Author: Liam Girdwood <lrg@slimlogic.co.uk>
8  *
9  *  This program is free software; you can redistribute  it and/or modify it
10  *  under  the terms of  the GNU General  Public License as published by the
11  *  Free Software Foundation;  either version 2 of the  License, or (at your
12  *  option) any later version.
13  *
14  */
15 
16 #include <linux/kernel.h>
17 #include <linux/init.h>
18 #include <linux/debugfs.h>
19 #include <linux/device.h>
20 #include <linux/slab.h>
21 #include <linux/async.h>
22 #include <linux/err.h>
23 #include <linux/mutex.h>
24 #include <linux/suspend.h>
25 #include <linux/delay.h>
26 #include <linux/gpio.h>
27 #include <linux/gpio/consumer.h>
28 #include <linux/of.h>
29 #include <linux/regmap.h>
30 #include <linux/regulator/of_regulator.h>
31 #include <linux/regulator/consumer.h>
32 #include <linux/regulator/driver.h>
33 #include <linux/regulator/machine.h>
34 #include <linux/module.h>
35 
36 #define CREATE_TRACE_POINTS
37 #include <trace/events/regulator.h>
38 
39 #include "dummy.h"
40 #include "internal.h"
41 
42 #define rdev_crit(rdev, fmt, ...)					\
43 	pr_crit("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
44 #define rdev_err(rdev, fmt, ...)					\
45 	pr_err("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
46 #define rdev_warn(rdev, fmt, ...)					\
47 	pr_warn("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
48 #define rdev_info(rdev, fmt, ...)					\
49 	pr_info("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
50 #define rdev_dbg(rdev, fmt, ...)					\
51 	pr_debug("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
52 
53 static DEFINE_MUTEX(regulator_list_mutex);
54 static LIST_HEAD(regulator_list);
55 static LIST_HEAD(regulator_map_list);
56 static LIST_HEAD(regulator_ena_gpio_list);
57 static LIST_HEAD(regulator_supply_alias_list);
58 static bool has_full_constraints;
59 
60 static struct dentry *debugfs_root;
61 
62 /*
63  * struct regulator_map
64  *
65  * Used to provide symbolic supply names to devices.
66  */
67 struct regulator_map {
68 	struct list_head list;
69 	const char *dev_name;   /* The dev_name() for the consumer */
70 	const char *supply;
71 	struct regulator_dev *regulator;
72 };
73 
74 /*
75  * struct regulator_enable_gpio
76  *
77  * Management for shared enable GPIO pin
78  */
79 struct regulator_enable_gpio {
80 	struct list_head list;
81 	struct gpio_desc *gpiod;
82 	u32 enable_count;	/* a number of enabled shared GPIO */
83 	u32 request_count;	/* a number of requested shared GPIO */
84 	unsigned int ena_gpio_invert:1;
85 };
86 
87 /*
88  * struct regulator_supply_alias
89  *
90  * Used to map lookups for a supply onto an alternative device.
91  */
92 struct regulator_supply_alias {
93 	struct list_head list;
94 	struct device *src_dev;
95 	const char *src_supply;
96 	struct device *alias_dev;
97 	const char *alias_supply;
98 };
99 
100 static int _regulator_is_enabled(struct regulator_dev *rdev);
101 static int _regulator_disable(struct regulator_dev *rdev);
102 static int _regulator_get_voltage(struct regulator_dev *rdev);
103 static int _regulator_get_current_limit(struct regulator_dev *rdev);
104 static unsigned int _regulator_get_mode(struct regulator_dev *rdev);
105 static int _notifier_call_chain(struct regulator_dev *rdev,
106 				  unsigned long event, void *data);
107 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
108 				     int min_uV, int max_uV);
109 static struct regulator *create_regulator(struct regulator_dev *rdev,
110 					  struct device *dev,
111 					  const char *supply_name);
112 static void _regulator_put(struct regulator *regulator);
113 
114 static struct regulator_dev *dev_to_rdev(struct device *dev)
115 {
116 	return container_of(dev, struct regulator_dev, dev);
117 }
118 
119 static const char *rdev_get_name(struct regulator_dev *rdev)
120 {
121 	if (rdev->constraints && rdev->constraints->name)
122 		return rdev->constraints->name;
123 	else if (rdev->desc->name)
124 		return rdev->desc->name;
125 	else
126 		return "";
127 }
128 
129 static bool have_full_constraints(void)
130 {
131 	return has_full_constraints || of_have_populated_dt();
132 }
133 
134 /**
135  * of_get_regulator - get a regulator device node based on supply name
136  * @dev: Device pointer for the consumer (of regulator) device
137  * @supply: regulator supply name
138  *
139  * Extract the regulator device node corresponding to the supply name.
140  * returns the device node corresponding to the regulator if found, else
141  * returns NULL.
142  */
143 static struct device_node *of_get_regulator(struct device *dev, const char *supply)
144 {
145 	struct device_node *regnode = NULL;
146 	char prop_name[32]; /* 32 is max size of property name */
147 
148 	dev_dbg(dev, "Looking up %s-supply from device tree\n", supply);
149 
150 	snprintf(prop_name, 32, "%s-supply", supply);
151 	regnode = of_parse_phandle(dev->of_node, prop_name, 0);
152 
153 	if (!regnode) {
154 		dev_dbg(dev, "Looking up %s property in node %s failed",
155 				prop_name, dev->of_node->full_name);
156 		return NULL;
157 	}
158 	return regnode;
159 }
160 
161 static int _regulator_can_change_status(struct regulator_dev *rdev)
162 {
163 	if (!rdev->constraints)
164 		return 0;
165 
166 	if (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_STATUS)
167 		return 1;
168 	else
169 		return 0;
170 }
171 
172 /* Platform voltage constraint check */
173 static int regulator_check_voltage(struct regulator_dev *rdev,
174 				   int *min_uV, int *max_uV)
175 {
176 	BUG_ON(*min_uV > *max_uV);
177 
178 	if (!rdev->constraints) {
179 		rdev_err(rdev, "no constraints\n");
180 		return -ENODEV;
181 	}
182 	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
183 		rdev_err(rdev, "operation not allowed\n");
184 		return -EPERM;
185 	}
186 
187 	if (*max_uV > rdev->constraints->max_uV)
188 		*max_uV = rdev->constraints->max_uV;
189 	if (*min_uV < rdev->constraints->min_uV)
190 		*min_uV = rdev->constraints->min_uV;
191 
192 	if (*min_uV > *max_uV) {
193 		rdev_err(rdev, "unsupportable voltage range: %d-%duV\n",
194 			 *min_uV, *max_uV);
195 		return -EINVAL;
196 	}
197 
198 	return 0;
199 }
200 
201 /* Make sure we select a voltage that suits the needs of all
202  * regulator consumers
203  */
204 static int regulator_check_consumers(struct regulator_dev *rdev,
205 				     int *min_uV, int *max_uV)
206 {
207 	struct regulator *regulator;
208 
209 	list_for_each_entry(regulator, &rdev->consumer_list, list) {
210 		/*
211 		 * Assume consumers that didn't say anything are OK
212 		 * with anything in the constraint range.
213 		 */
214 		if (!regulator->min_uV && !regulator->max_uV)
215 			continue;
216 
217 		if (*max_uV > regulator->max_uV)
218 			*max_uV = regulator->max_uV;
219 		if (*min_uV < regulator->min_uV)
220 			*min_uV = regulator->min_uV;
221 	}
222 
223 	if (*min_uV > *max_uV) {
224 		rdev_err(rdev, "Restricting voltage, %u-%uuV\n",
225 			*min_uV, *max_uV);
226 		return -EINVAL;
227 	}
228 
229 	return 0;
230 }
231 
232 /* current constraint check */
233 static int regulator_check_current_limit(struct regulator_dev *rdev,
234 					int *min_uA, int *max_uA)
235 {
236 	BUG_ON(*min_uA > *max_uA);
237 
238 	if (!rdev->constraints) {
239 		rdev_err(rdev, "no constraints\n");
240 		return -ENODEV;
241 	}
242 	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_CURRENT)) {
243 		rdev_err(rdev, "operation not allowed\n");
244 		return -EPERM;
245 	}
246 
247 	if (*max_uA > rdev->constraints->max_uA)
248 		*max_uA = rdev->constraints->max_uA;
249 	if (*min_uA < rdev->constraints->min_uA)
250 		*min_uA = rdev->constraints->min_uA;
251 
252 	if (*min_uA > *max_uA) {
253 		rdev_err(rdev, "unsupportable current range: %d-%duA\n",
254 			 *min_uA, *max_uA);
255 		return -EINVAL;
256 	}
257 
258 	return 0;
259 }
260 
261 /* operating mode constraint check */
262 static int regulator_mode_constrain(struct regulator_dev *rdev, int *mode)
263 {
264 	switch (*mode) {
265 	case REGULATOR_MODE_FAST:
266 	case REGULATOR_MODE_NORMAL:
267 	case REGULATOR_MODE_IDLE:
268 	case REGULATOR_MODE_STANDBY:
269 		break;
270 	default:
271 		rdev_err(rdev, "invalid mode %x specified\n", *mode);
272 		return -EINVAL;
273 	}
274 
275 	if (!rdev->constraints) {
276 		rdev_err(rdev, "no constraints\n");
277 		return -ENODEV;
278 	}
279 	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_MODE)) {
280 		rdev_err(rdev, "operation not allowed\n");
281 		return -EPERM;
282 	}
283 
284 	/* The modes are bitmasks, the most power hungry modes having
285 	 * the lowest values. If the requested mode isn't supported
286 	 * try higher modes. */
287 	while (*mode) {
288 		if (rdev->constraints->valid_modes_mask & *mode)
289 			return 0;
290 		*mode /= 2;
291 	}
292 
293 	return -EINVAL;
294 }
295 
296 /* dynamic regulator mode switching constraint check */
297 static int regulator_check_drms(struct regulator_dev *rdev)
298 {
299 	if (!rdev->constraints) {
300 		rdev_err(rdev, "no constraints\n");
301 		return -ENODEV;
302 	}
303 	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS)) {
304 		rdev_dbg(rdev, "operation not allowed\n");
305 		return -EPERM;
306 	}
307 	return 0;
308 }
309 
310 static ssize_t regulator_uV_show(struct device *dev,
311 				struct device_attribute *attr, char *buf)
312 {
313 	struct regulator_dev *rdev = dev_get_drvdata(dev);
314 	ssize_t ret;
315 
316 	mutex_lock(&rdev->mutex);
317 	ret = sprintf(buf, "%d\n", _regulator_get_voltage(rdev));
318 	mutex_unlock(&rdev->mutex);
319 
320 	return ret;
321 }
322 static DEVICE_ATTR(microvolts, 0444, regulator_uV_show, NULL);
323 
324 static ssize_t regulator_uA_show(struct device *dev,
325 				struct device_attribute *attr, char *buf)
326 {
327 	struct regulator_dev *rdev = dev_get_drvdata(dev);
328 
329 	return sprintf(buf, "%d\n", _regulator_get_current_limit(rdev));
330 }
331 static DEVICE_ATTR(microamps, 0444, regulator_uA_show, NULL);
332 
333 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
334 			 char *buf)
335 {
336 	struct regulator_dev *rdev = dev_get_drvdata(dev);
337 
338 	return sprintf(buf, "%s\n", rdev_get_name(rdev));
339 }
340 static DEVICE_ATTR_RO(name);
341 
342 static ssize_t regulator_print_opmode(char *buf, int mode)
343 {
344 	switch (mode) {
345 	case REGULATOR_MODE_FAST:
346 		return sprintf(buf, "fast\n");
347 	case REGULATOR_MODE_NORMAL:
348 		return sprintf(buf, "normal\n");
349 	case REGULATOR_MODE_IDLE:
350 		return sprintf(buf, "idle\n");
351 	case REGULATOR_MODE_STANDBY:
352 		return sprintf(buf, "standby\n");
353 	}
354 	return sprintf(buf, "unknown\n");
355 }
356 
357 static ssize_t regulator_opmode_show(struct device *dev,
358 				    struct device_attribute *attr, char *buf)
359 {
360 	struct regulator_dev *rdev = dev_get_drvdata(dev);
361 
362 	return regulator_print_opmode(buf, _regulator_get_mode(rdev));
363 }
364 static DEVICE_ATTR(opmode, 0444, regulator_opmode_show, NULL);
365 
366 static ssize_t regulator_print_state(char *buf, int state)
367 {
368 	if (state > 0)
369 		return sprintf(buf, "enabled\n");
370 	else if (state == 0)
371 		return sprintf(buf, "disabled\n");
372 	else
373 		return sprintf(buf, "unknown\n");
374 }
375 
376 static ssize_t regulator_state_show(struct device *dev,
377 				   struct device_attribute *attr, char *buf)
378 {
379 	struct regulator_dev *rdev = dev_get_drvdata(dev);
380 	ssize_t ret;
381 
382 	mutex_lock(&rdev->mutex);
383 	ret = regulator_print_state(buf, _regulator_is_enabled(rdev));
384 	mutex_unlock(&rdev->mutex);
385 
386 	return ret;
387 }
388 static DEVICE_ATTR(state, 0444, regulator_state_show, NULL);
389 
390 static ssize_t regulator_status_show(struct device *dev,
391 				   struct device_attribute *attr, char *buf)
392 {
393 	struct regulator_dev *rdev = dev_get_drvdata(dev);
394 	int status;
395 	char *label;
396 
397 	status = rdev->desc->ops->get_status(rdev);
398 	if (status < 0)
399 		return status;
400 
401 	switch (status) {
402 	case REGULATOR_STATUS_OFF:
403 		label = "off";
404 		break;
405 	case REGULATOR_STATUS_ON:
406 		label = "on";
407 		break;
408 	case REGULATOR_STATUS_ERROR:
409 		label = "error";
410 		break;
411 	case REGULATOR_STATUS_FAST:
412 		label = "fast";
413 		break;
414 	case REGULATOR_STATUS_NORMAL:
415 		label = "normal";
416 		break;
417 	case REGULATOR_STATUS_IDLE:
418 		label = "idle";
419 		break;
420 	case REGULATOR_STATUS_STANDBY:
421 		label = "standby";
422 		break;
423 	case REGULATOR_STATUS_BYPASS:
424 		label = "bypass";
425 		break;
426 	case REGULATOR_STATUS_UNDEFINED:
427 		label = "undefined";
428 		break;
429 	default:
430 		return -ERANGE;
431 	}
432 
433 	return sprintf(buf, "%s\n", label);
434 }
435 static DEVICE_ATTR(status, 0444, regulator_status_show, NULL);
436 
437 static ssize_t regulator_min_uA_show(struct device *dev,
438 				    struct device_attribute *attr, char *buf)
439 {
440 	struct regulator_dev *rdev = dev_get_drvdata(dev);
441 
442 	if (!rdev->constraints)
443 		return sprintf(buf, "constraint not defined\n");
444 
445 	return sprintf(buf, "%d\n", rdev->constraints->min_uA);
446 }
447 static DEVICE_ATTR(min_microamps, 0444, regulator_min_uA_show, NULL);
448 
449 static ssize_t regulator_max_uA_show(struct device *dev,
450 				    struct device_attribute *attr, char *buf)
451 {
452 	struct regulator_dev *rdev = dev_get_drvdata(dev);
453 
454 	if (!rdev->constraints)
455 		return sprintf(buf, "constraint not defined\n");
456 
457 	return sprintf(buf, "%d\n", rdev->constraints->max_uA);
458 }
459 static DEVICE_ATTR(max_microamps, 0444, regulator_max_uA_show, NULL);
460 
461 static ssize_t regulator_min_uV_show(struct device *dev,
462 				    struct device_attribute *attr, char *buf)
463 {
464 	struct regulator_dev *rdev = dev_get_drvdata(dev);
465 
466 	if (!rdev->constraints)
467 		return sprintf(buf, "constraint not defined\n");
468 
469 	return sprintf(buf, "%d\n", rdev->constraints->min_uV);
470 }
471 static DEVICE_ATTR(min_microvolts, 0444, regulator_min_uV_show, NULL);
472 
473 static ssize_t regulator_max_uV_show(struct device *dev,
474 				    struct device_attribute *attr, char *buf)
475 {
476 	struct regulator_dev *rdev = dev_get_drvdata(dev);
477 
478 	if (!rdev->constraints)
479 		return sprintf(buf, "constraint not defined\n");
480 
481 	return sprintf(buf, "%d\n", rdev->constraints->max_uV);
482 }
483 static DEVICE_ATTR(max_microvolts, 0444, regulator_max_uV_show, NULL);
484 
485 static ssize_t regulator_total_uA_show(struct device *dev,
486 				      struct device_attribute *attr, char *buf)
487 {
488 	struct regulator_dev *rdev = dev_get_drvdata(dev);
489 	struct regulator *regulator;
490 	int uA = 0;
491 
492 	mutex_lock(&rdev->mutex);
493 	list_for_each_entry(regulator, &rdev->consumer_list, list)
494 		uA += regulator->uA_load;
495 	mutex_unlock(&rdev->mutex);
496 	return sprintf(buf, "%d\n", uA);
497 }
498 static DEVICE_ATTR(requested_microamps, 0444, regulator_total_uA_show, NULL);
499 
500 static ssize_t num_users_show(struct device *dev, struct device_attribute *attr,
501 			      char *buf)
502 {
503 	struct regulator_dev *rdev = dev_get_drvdata(dev);
504 	return sprintf(buf, "%d\n", rdev->use_count);
505 }
506 static DEVICE_ATTR_RO(num_users);
507 
508 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
509 			 char *buf)
510 {
511 	struct regulator_dev *rdev = dev_get_drvdata(dev);
512 
513 	switch (rdev->desc->type) {
514 	case REGULATOR_VOLTAGE:
515 		return sprintf(buf, "voltage\n");
516 	case REGULATOR_CURRENT:
517 		return sprintf(buf, "current\n");
518 	}
519 	return sprintf(buf, "unknown\n");
520 }
521 static DEVICE_ATTR_RO(type);
522 
523 static ssize_t regulator_suspend_mem_uV_show(struct device *dev,
524 				struct device_attribute *attr, char *buf)
525 {
526 	struct regulator_dev *rdev = dev_get_drvdata(dev);
527 
528 	return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
529 }
530 static DEVICE_ATTR(suspend_mem_microvolts, 0444,
531 		regulator_suspend_mem_uV_show, NULL);
532 
533 static ssize_t regulator_suspend_disk_uV_show(struct device *dev,
534 				struct device_attribute *attr, char *buf)
535 {
536 	struct regulator_dev *rdev = dev_get_drvdata(dev);
537 
538 	return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
539 }
540 static DEVICE_ATTR(suspend_disk_microvolts, 0444,
541 		regulator_suspend_disk_uV_show, NULL);
542 
543 static ssize_t regulator_suspend_standby_uV_show(struct device *dev,
544 				struct device_attribute *attr, char *buf)
545 {
546 	struct regulator_dev *rdev = dev_get_drvdata(dev);
547 
548 	return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
549 }
550 static DEVICE_ATTR(suspend_standby_microvolts, 0444,
551 		regulator_suspend_standby_uV_show, NULL);
552 
553 static ssize_t regulator_suspend_mem_mode_show(struct device *dev,
554 				struct device_attribute *attr, char *buf)
555 {
556 	struct regulator_dev *rdev = dev_get_drvdata(dev);
557 
558 	return regulator_print_opmode(buf,
559 		rdev->constraints->state_mem.mode);
560 }
561 static DEVICE_ATTR(suspend_mem_mode, 0444,
562 		regulator_suspend_mem_mode_show, NULL);
563 
564 static ssize_t regulator_suspend_disk_mode_show(struct device *dev,
565 				struct device_attribute *attr, char *buf)
566 {
567 	struct regulator_dev *rdev = dev_get_drvdata(dev);
568 
569 	return regulator_print_opmode(buf,
570 		rdev->constraints->state_disk.mode);
571 }
572 static DEVICE_ATTR(suspend_disk_mode, 0444,
573 		regulator_suspend_disk_mode_show, NULL);
574 
575 static ssize_t regulator_suspend_standby_mode_show(struct device *dev,
576 				struct device_attribute *attr, char *buf)
577 {
578 	struct regulator_dev *rdev = dev_get_drvdata(dev);
579 
580 	return regulator_print_opmode(buf,
581 		rdev->constraints->state_standby.mode);
582 }
583 static DEVICE_ATTR(suspend_standby_mode, 0444,
584 		regulator_suspend_standby_mode_show, NULL);
585 
586 static ssize_t regulator_suspend_mem_state_show(struct device *dev,
587 				   struct device_attribute *attr, char *buf)
588 {
589 	struct regulator_dev *rdev = dev_get_drvdata(dev);
590 
591 	return regulator_print_state(buf,
592 			rdev->constraints->state_mem.enabled);
593 }
594 static DEVICE_ATTR(suspend_mem_state, 0444,
595 		regulator_suspend_mem_state_show, NULL);
596 
597 static ssize_t regulator_suspend_disk_state_show(struct device *dev,
598 				   struct device_attribute *attr, char *buf)
599 {
600 	struct regulator_dev *rdev = dev_get_drvdata(dev);
601 
602 	return regulator_print_state(buf,
603 			rdev->constraints->state_disk.enabled);
604 }
605 static DEVICE_ATTR(suspend_disk_state, 0444,
606 		regulator_suspend_disk_state_show, NULL);
607 
608 static ssize_t regulator_suspend_standby_state_show(struct device *dev,
609 				   struct device_attribute *attr, char *buf)
610 {
611 	struct regulator_dev *rdev = dev_get_drvdata(dev);
612 
613 	return regulator_print_state(buf,
614 			rdev->constraints->state_standby.enabled);
615 }
616 static DEVICE_ATTR(suspend_standby_state, 0444,
617 		regulator_suspend_standby_state_show, NULL);
618 
619 static ssize_t regulator_bypass_show(struct device *dev,
620 				     struct device_attribute *attr, char *buf)
621 {
622 	struct regulator_dev *rdev = dev_get_drvdata(dev);
623 	const char *report;
624 	bool bypass;
625 	int ret;
626 
627 	ret = rdev->desc->ops->get_bypass(rdev, &bypass);
628 
629 	if (ret != 0)
630 		report = "unknown";
631 	else if (bypass)
632 		report = "enabled";
633 	else
634 		report = "disabled";
635 
636 	return sprintf(buf, "%s\n", report);
637 }
638 static DEVICE_ATTR(bypass, 0444,
639 		   regulator_bypass_show, NULL);
640 
641 /* Calculate the new optimum regulator operating mode based on the new total
642  * consumer load. All locks held by caller */
643 static int drms_uA_update(struct regulator_dev *rdev)
644 {
645 	struct regulator *sibling;
646 	int current_uA = 0, output_uV, input_uV, err;
647 	unsigned int mode;
648 
649 	lockdep_assert_held_once(&rdev->mutex);
650 
651 	/*
652 	 * first check to see if we can set modes at all, otherwise just
653 	 * tell the consumer everything is OK.
654 	 */
655 	err = regulator_check_drms(rdev);
656 	if (err < 0)
657 		return 0;
658 
659 	if (!rdev->desc->ops->get_optimum_mode &&
660 	    !rdev->desc->ops->set_load)
661 		return 0;
662 
663 	if (!rdev->desc->ops->set_mode &&
664 	    !rdev->desc->ops->set_load)
665 		return -EINVAL;
666 
667 	/* get output voltage */
668 	output_uV = _regulator_get_voltage(rdev);
669 	if (output_uV <= 0) {
670 		rdev_err(rdev, "invalid output voltage found\n");
671 		return -EINVAL;
672 	}
673 
674 	/* get input voltage */
675 	input_uV = 0;
676 	if (rdev->supply)
677 		input_uV = regulator_get_voltage(rdev->supply);
678 	if (input_uV <= 0)
679 		input_uV = rdev->constraints->input_uV;
680 	if (input_uV <= 0) {
681 		rdev_err(rdev, "invalid input voltage found\n");
682 		return -EINVAL;
683 	}
684 
685 	/* calc total requested load */
686 	list_for_each_entry(sibling, &rdev->consumer_list, list)
687 		current_uA += sibling->uA_load;
688 
689 	current_uA += rdev->constraints->system_load;
690 
691 	if (rdev->desc->ops->set_load) {
692 		/* set the optimum mode for our new total regulator load */
693 		err = rdev->desc->ops->set_load(rdev, current_uA);
694 		if (err < 0)
695 			rdev_err(rdev, "failed to set load %d\n", current_uA);
696 	} else {
697 		/* now get the optimum mode for our new total regulator load */
698 		mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
699 							 output_uV, current_uA);
700 
701 		/* check the new mode is allowed */
702 		err = regulator_mode_constrain(rdev, &mode);
703 		if (err < 0) {
704 			rdev_err(rdev, "failed to get optimum mode @ %d uA %d -> %d uV\n",
705 				 current_uA, input_uV, output_uV);
706 			return err;
707 		}
708 
709 		err = rdev->desc->ops->set_mode(rdev, mode);
710 		if (err < 0)
711 			rdev_err(rdev, "failed to set optimum mode %x\n", mode);
712 	}
713 
714 	return err;
715 }
716 
717 static int suspend_set_state(struct regulator_dev *rdev,
718 	struct regulator_state *rstate)
719 {
720 	int ret = 0;
721 
722 	/* If we have no suspend mode configration don't set anything;
723 	 * only warn if the driver implements set_suspend_voltage or
724 	 * set_suspend_mode callback.
725 	 */
726 	if (!rstate->enabled && !rstate->disabled) {
727 		if (rdev->desc->ops->set_suspend_voltage ||
728 		    rdev->desc->ops->set_suspend_mode)
729 			rdev_warn(rdev, "No configuration\n");
730 		return 0;
731 	}
732 
733 	if (rstate->enabled && rstate->disabled) {
734 		rdev_err(rdev, "invalid configuration\n");
735 		return -EINVAL;
736 	}
737 
738 	if (rstate->enabled && rdev->desc->ops->set_suspend_enable)
739 		ret = rdev->desc->ops->set_suspend_enable(rdev);
740 	else if (rstate->disabled && rdev->desc->ops->set_suspend_disable)
741 		ret = rdev->desc->ops->set_suspend_disable(rdev);
742 	else /* OK if set_suspend_enable or set_suspend_disable is NULL */
743 		ret = 0;
744 
745 	if (ret < 0) {
746 		rdev_err(rdev, "failed to enabled/disable\n");
747 		return ret;
748 	}
749 
750 	if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
751 		ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
752 		if (ret < 0) {
753 			rdev_err(rdev, "failed to set voltage\n");
754 			return ret;
755 		}
756 	}
757 
758 	if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
759 		ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
760 		if (ret < 0) {
761 			rdev_err(rdev, "failed to set mode\n");
762 			return ret;
763 		}
764 	}
765 	return ret;
766 }
767 
768 /* locks held by caller */
769 static int suspend_prepare(struct regulator_dev *rdev, suspend_state_t state)
770 {
771 	lockdep_assert_held_once(&rdev->mutex);
772 
773 	if (!rdev->constraints)
774 		return -EINVAL;
775 
776 	switch (state) {
777 	case PM_SUSPEND_STANDBY:
778 		return suspend_set_state(rdev,
779 			&rdev->constraints->state_standby);
780 	case PM_SUSPEND_MEM:
781 		return suspend_set_state(rdev,
782 			&rdev->constraints->state_mem);
783 	case PM_SUSPEND_MAX:
784 		return suspend_set_state(rdev,
785 			&rdev->constraints->state_disk);
786 	default:
787 		return -EINVAL;
788 	}
789 }
790 
791 static void print_constraints(struct regulator_dev *rdev)
792 {
793 	struct regulation_constraints *constraints = rdev->constraints;
794 	char buf[160] = "";
795 	size_t len = sizeof(buf) - 1;
796 	int count = 0;
797 	int ret;
798 
799 	if (constraints->min_uV && constraints->max_uV) {
800 		if (constraints->min_uV == constraints->max_uV)
801 			count += scnprintf(buf + count, len - count, "%d mV ",
802 					   constraints->min_uV / 1000);
803 		else
804 			count += scnprintf(buf + count, len - count,
805 					   "%d <--> %d mV ",
806 					   constraints->min_uV / 1000,
807 					   constraints->max_uV / 1000);
808 	}
809 
810 	if (!constraints->min_uV ||
811 	    constraints->min_uV != constraints->max_uV) {
812 		ret = _regulator_get_voltage(rdev);
813 		if (ret > 0)
814 			count += scnprintf(buf + count, len - count,
815 					   "at %d mV ", ret / 1000);
816 	}
817 
818 	if (constraints->uV_offset)
819 		count += scnprintf(buf + count, len - count, "%dmV offset ",
820 				   constraints->uV_offset / 1000);
821 
822 	if (constraints->min_uA && constraints->max_uA) {
823 		if (constraints->min_uA == constraints->max_uA)
824 			count += scnprintf(buf + count, len - count, "%d mA ",
825 					   constraints->min_uA / 1000);
826 		else
827 			count += scnprintf(buf + count, len - count,
828 					   "%d <--> %d mA ",
829 					   constraints->min_uA / 1000,
830 					   constraints->max_uA / 1000);
831 	}
832 
833 	if (!constraints->min_uA ||
834 	    constraints->min_uA != constraints->max_uA) {
835 		ret = _regulator_get_current_limit(rdev);
836 		if (ret > 0)
837 			count += scnprintf(buf + count, len - count,
838 					   "at %d mA ", ret / 1000);
839 	}
840 
841 	if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
842 		count += scnprintf(buf + count, len - count, "fast ");
843 	if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
844 		count += scnprintf(buf + count, len - count, "normal ");
845 	if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
846 		count += scnprintf(buf + count, len - count, "idle ");
847 	if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
848 		count += scnprintf(buf + count, len - count, "standby");
849 
850 	if (!count)
851 		scnprintf(buf, len, "no parameters");
852 
853 	rdev_dbg(rdev, "%s\n", buf);
854 
855 	if ((constraints->min_uV != constraints->max_uV) &&
856 	    !(constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE))
857 		rdev_warn(rdev,
858 			  "Voltage range but no REGULATOR_CHANGE_VOLTAGE\n");
859 }
860 
861 static int machine_constraints_voltage(struct regulator_dev *rdev,
862 	struct regulation_constraints *constraints)
863 {
864 	const struct regulator_ops *ops = rdev->desc->ops;
865 	int ret;
866 
867 	/* do we need to apply the constraint voltage */
868 	if (rdev->constraints->apply_uV &&
869 	    rdev->constraints->min_uV == rdev->constraints->max_uV) {
870 		int current_uV = _regulator_get_voltage(rdev);
871 		if (current_uV < 0) {
872 			rdev_err(rdev,
873 				 "failed to get the current voltage(%d)\n",
874 				 current_uV);
875 			return current_uV;
876 		}
877 		if (current_uV < rdev->constraints->min_uV ||
878 		    current_uV > rdev->constraints->max_uV) {
879 			ret = _regulator_do_set_voltage(
880 				rdev, rdev->constraints->min_uV,
881 				rdev->constraints->max_uV);
882 			if (ret < 0) {
883 				rdev_err(rdev,
884 					"failed to apply %duV constraint(%d)\n",
885 					rdev->constraints->min_uV, ret);
886 				return ret;
887 			}
888 		}
889 	}
890 
891 	/* constrain machine-level voltage specs to fit
892 	 * the actual range supported by this regulator.
893 	 */
894 	if (ops->list_voltage && rdev->desc->n_voltages) {
895 		int	count = rdev->desc->n_voltages;
896 		int	i;
897 		int	min_uV = INT_MAX;
898 		int	max_uV = INT_MIN;
899 		int	cmin = constraints->min_uV;
900 		int	cmax = constraints->max_uV;
901 
902 		/* it's safe to autoconfigure fixed-voltage supplies
903 		   and the constraints are used by list_voltage. */
904 		if (count == 1 && !cmin) {
905 			cmin = 1;
906 			cmax = INT_MAX;
907 			constraints->min_uV = cmin;
908 			constraints->max_uV = cmax;
909 		}
910 
911 		/* voltage constraints are optional */
912 		if ((cmin == 0) && (cmax == 0))
913 			return 0;
914 
915 		/* else require explicit machine-level constraints */
916 		if (cmin <= 0 || cmax <= 0 || cmax < cmin) {
917 			rdev_err(rdev, "invalid voltage constraints\n");
918 			return -EINVAL;
919 		}
920 
921 		/* initial: [cmin..cmax] valid, [min_uV..max_uV] not */
922 		for (i = 0; i < count; i++) {
923 			int	value;
924 
925 			value = ops->list_voltage(rdev, i);
926 			if (value <= 0)
927 				continue;
928 
929 			/* maybe adjust [min_uV..max_uV] */
930 			if (value >= cmin && value < min_uV)
931 				min_uV = value;
932 			if (value <= cmax && value > max_uV)
933 				max_uV = value;
934 		}
935 
936 		/* final: [min_uV..max_uV] valid iff constraints valid */
937 		if (max_uV < min_uV) {
938 			rdev_err(rdev,
939 				 "unsupportable voltage constraints %u-%uuV\n",
940 				 min_uV, max_uV);
941 			return -EINVAL;
942 		}
943 
944 		/* use regulator's subset of machine constraints */
945 		if (constraints->min_uV < min_uV) {
946 			rdev_dbg(rdev, "override min_uV, %d -> %d\n",
947 				 constraints->min_uV, min_uV);
948 			constraints->min_uV = min_uV;
949 		}
950 		if (constraints->max_uV > max_uV) {
951 			rdev_dbg(rdev, "override max_uV, %d -> %d\n",
952 				 constraints->max_uV, max_uV);
953 			constraints->max_uV = max_uV;
954 		}
955 	}
956 
957 	return 0;
958 }
959 
960 static int machine_constraints_current(struct regulator_dev *rdev,
961 	struct regulation_constraints *constraints)
962 {
963 	const struct regulator_ops *ops = rdev->desc->ops;
964 	int ret;
965 
966 	if (!constraints->min_uA && !constraints->max_uA)
967 		return 0;
968 
969 	if (constraints->min_uA > constraints->max_uA) {
970 		rdev_err(rdev, "Invalid current constraints\n");
971 		return -EINVAL;
972 	}
973 
974 	if (!ops->set_current_limit || !ops->get_current_limit) {
975 		rdev_warn(rdev, "Operation of current configuration missing\n");
976 		return 0;
977 	}
978 
979 	/* Set regulator current in constraints range */
980 	ret = ops->set_current_limit(rdev, constraints->min_uA,
981 			constraints->max_uA);
982 	if (ret < 0) {
983 		rdev_err(rdev, "Failed to set current constraint, %d\n", ret);
984 		return ret;
985 	}
986 
987 	return 0;
988 }
989 
990 static int _regulator_do_enable(struct regulator_dev *rdev);
991 
992 /**
993  * set_machine_constraints - sets regulator constraints
994  * @rdev: regulator source
995  * @constraints: constraints to apply
996  *
997  * Allows platform initialisation code to define and constrain
998  * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
999  * Constraints *must* be set by platform code in order for some
1000  * regulator operations to proceed i.e. set_voltage, set_current_limit,
1001  * set_mode.
1002  */
1003 static int set_machine_constraints(struct regulator_dev *rdev,
1004 	const struct regulation_constraints *constraints)
1005 {
1006 	int ret = 0;
1007 	const struct regulator_ops *ops = rdev->desc->ops;
1008 
1009 	if (constraints)
1010 		rdev->constraints = kmemdup(constraints, sizeof(*constraints),
1011 					    GFP_KERNEL);
1012 	else
1013 		rdev->constraints = kzalloc(sizeof(*constraints),
1014 					    GFP_KERNEL);
1015 	if (!rdev->constraints)
1016 		return -ENOMEM;
1017 
1018 	ret = machine_constraints_voltage(rdev, rdev->constraints);
1019 	if (ret != 0)
1020 		goto out;
1021 
1022 	ret = machine_constraints_current(rdev, rdev->constraints);
1023 	if (ret != 0)
1024 		goto out;
1025 
1026 	if (rdev->constraints->ilim_uA && ops->set_input_current_limit) {
1027 		ret = ops->set_input_current_limit(rdev,
1028 						   rdev->constraints->ilim_uA);
1029 		if (ret < 0) {
1030 			rdev_err(rdev, "failed to set input limit\n");
1031 			goto out;
1032 		}
1033 	}
1034 
1035 	/* do we need to setup our suspend state */
1036 	if (rdev->constraints->initial_state) {
1037 		ret = suspend_prepare(rdev, rdev->constraints->initial_state);
1038 		if (ret < 0) {
1039 			rdev_err(rdev, "failed to set suspend state\n");
1040 			goto out;
1041 		}
1042 	}
1043 
1044 	if (rdev->constraints->initial_mode) {
1045 		if (!ops->set_mode) {
1046 			rdev_err(rdev, "no set_mode operation\n");
1047 			ret = -EINVAL;
1048 			goto out;
1049 		}
1050 
1051 		ret = ops->set_mode(rdev, rdev->constraints->initial_mode);
1052 		if (ret < 0) {
1053 			rdev_err(rdev, "failed to set initial mode: %d\n", ret);
1054 			goto out;
1055 		}
1056 	}
1057 
1058 	/* If the constraints say the regulator should be on at this point
1059 	 * and we have control then make sure it is enabled.
1060 	 */
1061 	if (rdev->constraints->always_on || rdev->constraints->boot_on) {
1062 		ret = _regulator_do_enable(rdev);
1063 		if (ret < 0 && ret != -EINVAL) {
1064 			rdev_err(rdev, "failed to enable\n");
1065 			goto out;
1066 		}
1067 	}
1068 
1069 	if ((rdev->constraints->ramp_delay || rdev->constraints->ramp_disable)
1070 		&& ops->set_ramp_delay) {
1071 		ret = ops->set_ramp_delay(rdev, rdev->constraints->ramp_delay);
1072 		if (ret < 0) {
1073 			rdev_err(rdev, "failed to set ramp_delay\n");
1074 			goto out;
1075 		}
1076 	}
1077 
1078 	if (rdev->constraints->pull_down && ops->set_pull_down) {
1079 		ret = ops->set_pull_down(rdev);
1080 		if (ret < 0) {
1081 			rdev_err(rdev, "failed to set pull down\n");
1082 			goto out;
1083 		}
1084 	}
1085 
1086 	if (rdev->constraints->soft_start && ops->set_soft_start) {
1087 		ret = ops->set_soft_start(rdev);
1088 		if (ret < 0) {
1089 			rdev_err(rdev, "failed to set soft start\n");
1090 			goto out;
1091 		}
1092 	}
1093 
1094 	if (rdev->constraints->over_current_protection
1095 		&& ops->set_over_current_protection) {
1096 		ret = ops->set_over_current_protection(rdev);
1097 		if (ret < 0) {
1098 			rdev_err(rdev, "failed to set over current protection\n");
1099 			goto out;
1100 		}
1101 	}
1102 
1103 	print_constraints(rdev);
1104 	return 0;
1105 out:
1106 	kfree(rdev->constraints);
1107 	rdev->constraints = NULL;
1108 	return ret;
1109 }
1110 
1111 /**
1112  * set_supply - set regulator supply regulator
1113  * @rdev: regulator name
1114  * @supply_rdev: supply regulator name
1115  *
1116  * Called by platform initialisation code to set the supply regulator for this
1117  * regulator. This ensures that a regulators supply will also be enabled by the
1118  * core if it's child is enabled.
1119  */
1120 static int set_supply(struct regulator_dev *rdev,
1121 		      struct regulator_dev *supply_rdev)
1122 {
1123 	int err;
1124 
1125 	rdev_info(rdev, "supplied by %s\n", rdev_get_name(supply_rdev));
1126 
1127 	if (!try_module_get(supply_rdev->owner))
1128 		return -ENODEV;
1129 
1130 	rdev->supply = create_regulator(supply_rdev, &rdev->dev, "SUPPLY");
1131 	if (rdev->supply == NULL) {
1132 		err = -ENOMEM;
1133 		return err;
1134 	}
1135 	supply_rdev->open_count++;
1136 
1137 	return 0;
1138 }
1139 
1140 /**
1141  * set_consumer_device_supply - Bind a regulator to a symbolic supply
1142  * @rdev:         regulator source
1143  * @consumer_dev_name: dev_name() string for device supply applies to
1144  * @supply:       symbolic name for supply
1145  *
1146  * Allows platform initialisation code to map physical regulator
1147  * sources to symbolic names for supplies for use by devices.  Devices
1148  * should use these symbolic names to request regulators, avoiding the
1149  * need to provide board-specific regulator names as platform data.
1150  */
1151 static int set_consumer_device_supply(struct regulator_dev *rdev,
1152 				      const char *consumer_dev_name,
1153 				      const char *supply)
1154 {
1155 	struct regulator_map *node;
1156 	int has_dev;
1157 
1158 	if (supply == NULL)
1159 		return -EINVAL;
1160 
1161 	if (consumer_dev_name != NULL)
1162 		has_dev = 1;
1163 	else
1164 		has_dev = 0;
1165 
1166 	list_for_each_entry(node, &regulator_map_list, list) {
1167 		if (node->dev_name && consumer_dev_name) {
1168 			if (strcmp(node->dev_name, consumer_dev_name) != 0)
1169 				continue;
1170 		} else if (node->dev_name || consumer_dev_name) {
1171 			continue;
1172 		}
1173 
1174 		if (strcmp(node->supply, supply) != 0)
1175 			continue;
1176 
1177 		pr_debug("%s: %s/%s is '%s' supply; fail %s/%s\n",
1178 			 consumer_dev_name,
1179 			 dev_name(&node->regulator->dev),
1180 			 node->regulator->desc->name,
1181 			 supply,
1182 			 dev_name(&rdev->dev), rdev_get_name(rdev));
1183 		return -EBUSY;
1184 	}
1185 
1186 	node = kzalloc(sizeof(struct regulator_map), GFP_KERNEL);
1187 	if (node == NULL)
1188 		return -ENOMEM;
1189 
1190 	node->regulator = rdev;
1191 	node->supply = supply;
1192 
1193 	if (has_dev) {
1194 		node->dev_name = kstrdup(consumer_dev_name, GFP_KERNEL);
1195 		if (node->dev_name == NULL) {
1196 			kfree(node);
1197 			return -ENOMEM;
1198 		}
1199 	}
1200 
1201 	list_add(&node->list, &regulator_map_list);
1202 	return 0;
1203 }
1204 
1205 static void unset_regulator_supplies(struct regulator_dev *rdev)
1206 {
1207 	struct regulator_map *node, *n;
1208 
1209 	list_for_each_entry_safe(node, n, &regulator_map_list, list) {
1210 		if (rdev == node->regulator) {
1211 			list_del(&node->list);
1212 			kfree(node->dev_name);
1213 			kfree(node);
1214 		}
1215 	}
1216 }
1217 
1218 #define REG_STR_SIZE	64
1219 
1220 static struct regulator *create_regulator(struct regulator_dev *rdev,
1221 					  struct device *dev,
1222 					  const char *supply_name)
1223 {
1224 	struct regulator *regulator;
1225 	char buf[REG_STR_SIZE];
1226 	int err, size;
1227 
1228 	regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
1229 	if (regulator == NULL)
1230 		return NULL;
1231 
1232 	mutex_lock(&rdev->mutex);
1233 	regulator->rdev = rdev;
1234 	list_add(&regulator->list, &rdev->consumer_list);
1235 
1236 	if (dev) {
1237 		regulator->dev = dev;
1238 
1239 		/* Add a link to the device sysfs entry */
1240 		size = scnprintf(buf, REG_STR_SIZE, "%s-%s",
1241 				 dev->kobj.name, supply_name);
1242 		if (size >= REG_STR_SIZE)
1243 			goto overflow_err;
1244 
1245 		regulator->supply_name = kstrdup(buf, GFP_KERNEL);
1246 		if (regulator->supply_name == NULL)
1247 			goto overflow_err;
1248 
1249 		err = sysfs_create_link_nowarn(&rdev->dev.kobj, &dev->kobj,
1250 					buf);
1251 		if (err) {
1252 			rdev_dbg(rdev, "could not add device link %s err %d\n",
1253 				  dev->kobj.name, err);
1254 			/* non-fatal */
1255 		}
1256 	} else {
1257 		regulator->supply_name = kstrdup(supply_name, GFP_KERNEL);
1258 		if (regulator->supply_name == NULL)
1259 			goto overflow_err;
1260 	}
1261 
1262 	regulator->debugfs = debugfs_create_dir(regulator->supply_name,
1263 						rdev->debugfs);
1264 	if (!regulator->debugfs) {
1265 		rdev_dbg(rdev, "Failed to create debugfs directory\n");
1266 	} else {
1267 		debugfs_create_u32("uA_load", 0444, regulator->debugfs,
1268 				   &regulator->uA_load);
1269 		debugfs_create_u32("min_uV", 0444, regulator->debugfs,
1270 				   &regulator->min_uV);
1271 		debugfs_create_u32("max_uV", 0444, regulator->debugfs,
1272 				   &regulator->max_uV);
1273 	}
1274 
1275 	/*
1276 	 * Check now if the regulator is an always on regulator - if
1277 	 * it is then we don't need to do nearly so much work for
1278 	 * enable/disable calls.
1279 	 */
1280 	if (!_regulator_can_change_status(rdev) &&
1281 	    _regulator_is_enabled(rdev))
1282 		regulator->always_on = true;
1283 
1284 	mutex_unlock(&rdev->mutex);
1285 	return regulator;
1286 overflow_err:
1287 	list_del(&regulator->list);
1288 	kfree(regulator);
1289 	mutex_unlock(&rdev->mutex);
1290 	return NULL;
1291 }
1292 
1293 static int _regulator_get_enable_time(struct regulator_dev *rdev)
1294 {
1295 	if (rdev->constraints && rdev->constraints->enable_time)
1296 		return rdev->constraints->enable_time;
1297 	if (!rdev->desc->ops->enable_time)
1298 		return rdev->desc->enable_time;
1299 	return rdev->desc->ops->enable_time(rdev);
1300 }
1301 
1302 static struct regulator_supply_alias *regulator_find_supply_alias(
1303 		struct device *dev, const char *supply)
1304 {
1305 	struct regulator_supply_alias *map;
1306 
1307 	list_for_each_entry(map, &regulator_supply_alias_list, list)
1308 		if (map->src_dev == dev && strcmp(map->src_supply, supply) == 0)
1309 			return map;
1310 
1311 	return NULL;
1312 }
1313 
1314 static void regulator_supply_alias(struct device **dev, const char **supply)
1315 {
1316 	struct regulator_supply_alias *map;
1317 
1318 	map = regulator_find_supply_alias(*dev, *supply);
1319 	if (map) {
1320 		dev_dbg(*dev, "Mapping supply %s to %s,%s\n",
1321 				*supply, map->alias_supply,
1322 				dev_name(map->alias_dev));
1323 		*dev = map->alias_dev;
1324 		*supply = map->alias_supply;
1325 	}
1326 }
1327 
1328 static struct regulator_dev *regulator_dev_lookup(struct device *dev,
1329 						  const char *supply,
1330 						  int *ret)
1331 {
1332 	struct regulator_dev *r;
1333 	struct device_node *node;
1334 	struct regulator_map *map;
1335 	const char *devname = NULL;
1336 
1337 	regulator_supply_alias(&dev, &supply);
1338 
1339 	/* first do a dt based lookup */
1340 	if (dev && dev->of_node) {
1341 		node = of_get_regulator(dev, supply);
1342 		if (node) {
1343 			list_for_each_entry(r, &regulator_list, list)
1344 				if (r->dev.parent &&
1345 					node == r->dev.of_node)
1346 					return r;
1347 			*ret = -EPROBE_DEFER;
1348 			return NULL;
1349 		} else {
1350 			/*
1351 			 * If we couldn't even get the node then it's
1352 			 * not just that the device didn't register
1353 			 * yet, there's no node and we'll never
1354 			 * succeed.
1355 			 */
1356 			*ret = -ENODEV;
1357 		}
1358 	}
1359 
1360 	/* if not found, try doing it non-dt way */
1361 	if (dev)
1362 		devname = dev_name(dev);
1363 
1364 	list_for_each_entry(r, &regulator_list, list)
1365 		if (strcmp(rdev_get_name(r), supply) == 0)
1366 			return r;
1367 
1368 	list_for_each_entry(map, &regulator_map_list, list) {
1369 		/* If the mapping has a device set up it must match */
1370 		if (map->dev_name &&
1371 		    (!devname || strcmp(map->dev_name, devname)))
1372 			continue;
1373 
1374 		if (strcmp(map->supply, supply) == 0)
1375 			return map->regulator;
1376 	}
1377 
1378 
1379 	return NULL;
1380 }
1381 
1382 static int regulator_resolve_supply(struct regulator_dev *rdev)
1383 {
1384 	struct regulator_dev *r;
1385 	struct device *dev = rdev->dev.parent;
1386 	int ret;
1387 
1388 	/* No supply to resovle? */
1389 	if (!rdev->supply_name)
1390 		return 0;
1391 
1392 	/* Supply already resolved? */
1393 	if (rdev->supply)
1394 		return 0;
1395 
1396 	r = regulator_dev_lookup(dev, rdev->supply_name, &ret);
1397 	if (ret == -ENODEV) {
1398 		/*
1399 		 * No supply was specified for this regulator and
1400 		 * there will never be one.
1401 		 */
1402 		return 0;
1403 	}
1404 
1405 	if (!r) {
1406 		if (have_full_constraints()) {
1407 			r = dummy_regulator_rdev;
1408 		} else {
1409 			dev_err(dev, "Failed to resolve %s-supply for %s\n",
1410 				rdev->supply_name, rdev->desc->name);
1411 			return -EPROBE_DEFER;
1412 		}
1413 	}
1414 
1415 	/* Recursively resolve the supply of the supply */
1416 	ret = regulator_resolve_supply(r);
1417 	if (ret < 0)
1418 		return ret;
1419 
1420 	ret = set_supply(rdev, r);
1421 	if (ret < 0)
1422 		return ret;
1423 
1424 	/* Cascade always-on state to supply */
1425 	if (_regulator_is_enabled(rdev)) {
1426 		ret = regulator_enable(rdev->supply);
1427 		if (ret < 0) {
1428 			if (rdev->supply)
1429 				_regulator_put(rdev->supply);
1430 			return ret;
1431 		}
1432 	}
1433 
1434 	return 0;
1435 }
1436 
1437 /* Internal regulator request function */
1438 static struct regulator *_regulator_get(struct device *dev, const char *id,
1439 					bool exclusive, bool allow_dummy)
1440 {
1441 	struct regulator_dev *rdev;
1442 	struct regulator *regulator = ERR_PTR(-EPROBE_DEFER);
1443 	const char *devname = NULL;
1444 	int ret;
1445 
1446 	if (id == NULL) {
1447 		pr_err("get() with no identifier\n");
1448 		return ERR_PTR(-EINVAL);
1449 	}
1450 
1451 	if (dev)
1452 		devname = dev_name(dev);
1453 
1454 	if (have_full_constraints())
1455 		ret = -ENODEV;
1456 	else
1457 		ret = -EPROBE_DEFER;
1458 
1459 	mutex_lock(&regulator_list_mutex);
1460 
1461 	rdev = regulator_dev_lookup(dev, id, &ret);
1462 	if (rdev)
1463 		goto found;
1464 
1465 	regulator = ERR_PTR(ret);
1466 
1467 	/*
1468 	 * If we have return value from dev_lookup fail, we do not expect to
1469 	 * succeed, so, quit with appropriate error value
1470 	 */
1471 	if (ret && ret != -ENODEV)
1472 		goto out;
1473 
1474 	if (!devname)
1475 		devname = "deviceless";
1476 
1477 	/*
1478 	 * Assume that a regulator is physically present and enabled
1479 	 * even if it isn't hooked up and just provide a dummy.
1480 	 */
1481 	if (have_full_constraints() && allow_dummy) {
1482 		pr_warn("%s supply %s not found, using dummy regulator\n",
1483 			devname, id);
1484 
1485 		rdev = dummy_regulator_rdev;
1486 		goto found;
1487 	/* Don't log an error when called from regulator_get_optional() */
1488 	} else if (!have_full_constraints() || exclusive) {
1489 		dev_warn(dev, "dummy supplies not allowed\n");
1490 	}
1491 
1492 	mutex_unlock(&regulator_list_mutex);
1493 	return regulator;
1494 
1495 found:
1496 	if (rdev->exclusive) {
1497 		regulator = ERR_PTR(-EPERM);
1498 		goto out;
1499 	}
1500 
1501 	if (exclusive && rdev->open_count) {
1502 		regulator = ERR_PTR(-EBUSY);
1503 		goto out;
1504 	}
1505 
1506 	ret = regulator_resolve_supply(rdev);
1507 	if (ret < 0) {
1508 		regulator = ERR_PTR(ret);
1509 		goto out;
1510 	}
1511 
1512 	if (!try_module_get(rdev->owner))
1513 		goto out;
1514 
1515 	regulator = create_regulator(rdev, dev, id);
1516 	if (regulator == NULL) {
1517 		regulator = ERR_PTR(-ENOMEM);
1518 		module_put(rdev->owner);
1519 		goto out;
1520 	}
1521 
1522 	rdev->open_count++;
1523 	if (exclusive) {
1524 		rdev->exclusive = 1;
1525 
1526 		ret = _regulator_is_enabled(rdev);
1527 		if (ret > 0)
1528 			rdev->use_count = 1;
1529 		else
1530 			rdev->use_count = 0;
1531 	}
1532 
1533 out:
1534 	mutex_unlock(&regulator_list_mutex);
1535 
1536 	return regulator;
1537 }
1538 
1539 /**
1540  * regulator_get - lookup and obtain a reference to a regulator.
1541  * @dev: device for regulator "consumer"
1542  * @id: Supply name or regulator ID.
1543  *
1544  * Returns a struct regulator corresponding to the regulator producer,
1545  * or IS_ERR() condition containing errno.
1546  *
1547  * Use of supply names configured via regulator_set_device_supply() is
1548  * strongly encouraged.  It is recommended that the supply name used
1549  * should match the name used for the supply and/or the relevant
1550  * device pins in the datasheet.
1551  */
1552 struct regulator *regulator_get(struct device *dev, const char *id)
1553 {
1554 	return _regulator_get(dev, id, false, true);
1555 }
1556 EXPORT_SYMBOL_GPL(regulator_get);
1557 
1558 /**
1559  * regulator_get_exclusive - obtain exclusive access to a regulator.
1560  * @dev: device for regulator "consumer"
1561  * @id: Supply name or regulator ID.
1562  *
1563  * Returns a struct regulator corresponding to the regulator producer,
1564  * or IS_ERR() condition containing errno.  Other consumers will be
1565  * unable to obtain this regulator while this reference is held and the
1566  * use count for the regulator will be initialised to reflect the current
1567  * state of the regulator.
1568  *
1569  * This is intended for use by consumers which cannot tolerate shared
1570  * use of the regulator such as those which need to force the
1571  * regulator off for correct operation of the hardware they are
1572  * controlling.
1573  *
1574  * Use of supply names configured via regulator_set_device_supply() is
1575  * strongly encouraged.  It is recommended that the supply name used
1576  * should match the name used for the supply and/or the relevant
1577  * device pins in the datasheet.
1578  */
1579 struct regulator *regulator_get_exclusive(struct device *dev, const char *id)
1580 {
1581 	return _regulator_get(dev, id, true, false);
1582 }
1583 EXPORT_SYMBOL_GPL(regulator_get_exclusive);
1584 
1585 /**
1586  * regulator_get_optional - obtain optional access to a regulator.
1587  * @dev: device for regulator "consumer"
1588  * @id: Supply name or regulator ID.
1589  *
1590  * Returns a struct regulator corresponding to the regulator producer,
1591  * or IS_ERR() condition containing errno.
1592  *
1593  * This is intended for use by consumers for devices which can have
1594  * some supplies unconnected in normal use, such as some MMC devices.
1595  * It can allow the regulator core to provide stub supplies for other
1596  * supplies requested using normal regulator_get() calls without
1597  * disrupting the operation of drivers that can handle absent
1598  * supplies.
1599  *
1600  * Use of supply names configured via regulator_set_device_supply() is
1601  * strongly encouraged.  It is recommended that the supply name used
1602  * should match the name used for the supply and/or the relevant
1603  * device pins in the datasheet.
1604  */
1605 struct regulator *regulator_get_optional(struct device *dev, const char *id)
1606 {
1607 	return _regulator_get(dev, id, false, false);
1608 }
1609 EXPORT_SYMBOL_GPL(regulator_get_optional);
1610 
1611 /* regulator_list_mutex lock held by regulator_put() */
1612 static void _regulator_put(struct regulator *regulator)
1613 {
1614 	struct regulator_dev *rdev;
1615 
1616 	if (IS_ERR_OR_NULL(regulator))
1617 		return;
1618 
1619 	lockdep_assert_held_once(&regulator_list_mutex);
1620 
1621 	rdev = regulator->rdev;
1622 
1623 	debugfs_remove_recursive(regulator->debugfs);
1624 
1625 	/* remove any sysfs entries */
1626 	if (regulator->dev)
1627 		sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
1628 	mutex_lock(&rdev->mutex);
1629 	list_del(&regulator->list);
1630 
1631 	rdev->open_count--;
1632 	rdev->exclusive = 0;
1633 	mutex_unlock(&rdev->mutex);
1634 
1635 	kfree(regulator->supply_name);
1636 	kfree(regulator);
1637 
1638 	module_put(rdev->owner);
1639 }
1640 
1641 /**
1642  * regulator_put - "free" the regulator source
1643  * @regulator: regulator source
1644  *
1645  * Note: drivers must ensure that all regulator_enable calls made on this
1646  * regulator source are balanced by regulator_disable calls prior to calling
1647  * this function.
1648  */
1649 void regulator_put(struct regulator *regulator)
1650 {
1651 	mutex_lock(&regulator_list_mutex);
1652 	_regulator_put(regulator);
1653 	mutex_unlock(&regulator_list_mutex);
1654 }
1655 EXPORT_SYMBOL_GPL(regulator_put);
1656 
1657 /**
1658  * regulator_register_supply_alias - Provide device alias for supply lookup
1659  *
1660  * @dev: device that will be given as the regulator "consumer"
1661  * @id: Supply name or regulator ID
1662  * @alias_dev: device that should be used to lookup the supply
1663  * @alias_id: Supply name or regulator ID that should be used to lookup the
1664  * supply
1665  *
1666  * All lookups for id on dev will instead be conducted for alias_id on
1667  * alias_dev.
1668  */
1669 int regulator_register_supply_alias(struct device *dev, const char *id,
1670 				    struct device *alias_dev,
1671 				    const char *alias_id)
1672 {
1673 	struct regulator_supply_alias *map;
1674 
1675 	map = regulator_find_supply_alias(dev, id);
1676 	if (map)
1677 		return -EEXIST;
1678 
1679 	map = kzalloc(sizeof(struct regulator_supply_alias), GFP_KERNEL);
1680 	if (!map)
1681 		return -ENOMEM;
1682 
1683 	map->src_dev = dev;
1684 	map->src_supply = id;
1685 	map->alias_dev = alias_dev;
1686 	map->alias_supply = alias_id;
1687 
1688 	list_add(&map->list, &regulator_supply_alias_list);
1689 
1690 	pr_info("Adding alias for supply %s,%s -> %s,%s\n",
1691 		id, dev_name(dev), alias_id, dev_name(alias_dev));
1692 
1693 	return 0;
1694 }
1695 EXPORT_SYMBOL_GPL(regulator_register_supply_alias);
1696 
1697 /**
1698  * regulator_unregister_supply_alias - Remove device alias
1699  *
1700  * @dev: device that will be given as the regulator "consumer"
1701  * @id: Supply name or regulator ID
1702  *
1703  * Remove a lookup alias if one exists for id on dev.
1704  */
1705 void regulator_unregister_supply_alias(struct device *dev, const char *id)
1706 {
1707 	struct regulator_supply_alias *map;
1708 
1709 	map = regulator_find_supply_alias(dev, id);
1710 	if (map) {
1711 		list_del(&map->list);
1712 		kfree(map);
1713 	}
1714 }
1715 EXPORT_SYMBOL_GPL(regulator_unregister_supply_alias);
1716 
1717 /**
1718  * regulator_bulk_register_supply_alias - register multiple aliases
1719  *
1720  * @dev: device that will be given as the regulator "consumer"
1721  * @id: List of supply names or regulator IDs
1722  * @alias_dev: device that should be used to lookup the supply
1723  * @alias_id: List of supply names or regulator IDs that should be used to
1724  * lookup the supply
1725  * @num_id: Number of aliases to register
1726  *
1727  * @return 0 on success, an errno on failure.
1728  *
1729  * This helper function allows drivers to register several supply
1730  * aliases in one operation.  If any of the aliases cannot be
1731  * registered any aliases that were registered will be removed
1732  * before returning to the caller.
1733  */
1734 int regulator_bulk_register_supply_alias(struct device *dev,
1735 					 const char *const *id,
1736 					 struct device *alias_dev,
1737 					 const char *const *alias_id,
1738 					 int num_id)
1739 {
1740 	int i;
1741 	int ret;
1742 
1743 	for (i = 0; i < num_id; ++i) {
1744 		ret = regulator_register_supply_alias(dev, id[i], alias_dev,
1745 						      alias_id[i]);
1746 		if (ret < 0)
1747 			goto err;
1748 	}
1749 
1750 	return 0;
1751 
1752 err:
1753 	dev_err(dev,
1754 		"Failed to create supply alias %s,%s -> %s,%s\n",
1755 		id[i], dev_name(dev), alias_id[i], dev_name(alias_dev));
1756 
1757 	while (--i >= 0)
1758 		regulator_unregister_supply_alias(dev, id[i]);
1759 
1760 	return ret;
1761 }
1762 EXPORT_SYMBOL_GPL(regulator_bulk_register_supply_alias);
1763 
1764 /**
1765  * regulator_bulk_unregister_supply_alias - unregister multiple aliases
1766  *
1767  * @dev: device that will be given as the regulator "consumer"
1768  * @id: List of supply names or regulator IDs
1769  * @num_id: Number of aliases to unregister
1770  *
1771  * This helper function allows drivers to unregister several supply
1772  * aliases in one operation.
1773  */
1774 void regulator_bulk_unregister_supply_alias(struct device *dev,
1775 					    const char *const *id,
1776 					    int num_id)
1777 {
1778 	int i;
1779 
1780 	for (i = 0; i < num_id; ++i)
1781 		regulator_unregister_supply_alias(dev, id[i]);
1782 }
1783 EXPORT_SYMBOL_GPL(regulator_bulk_unregister_supply_alias);
1784 
1785 
1786 /* Manage enable GPIO list. Same GPIO pin can be shared among regulators */
1787 static int regulator_ena_gpio_request(struct regulator_dev *rdev,
1788 				const struct regulator_config *config)
1789 {
1790 	struct regulator_enable_gpio *pin;
1791 	struct gpio_desc *gpiod;
1792 	int ret;
1793 
1794 	gpiod = gpio_to_desc(config->ena_gpio);
1795 
1796 	list_for_each_entry(pin, &regulator_ena_gpio_list, list) {
1797 		if (pin->gpiod == gpiod) {
1798 			rdev_dbg(rdev, "GPIO %d is already used\n",
1799 				config->ena_gpio);
1800 			goto update_ena_gpio_to_rdev;
1801 		}
1802 	}
1803 
1804 	ret = gpio_request_one(config->ena_gpio,
1805 				GPIOF_DIR_OUT | config->ena_gpio_flags,
1806 				rdev_get_name(rdev));
1807 	if (ret)
1808 		return ret;
1809 
1810 	pin = kzalloc(sizeof(struct regulator_enable_gpio), GFP_KERNEL);
1811 	if (pin == NULL) {
1812 		gpio_free(config->ena_gpio);
1813 		return -ENOMEM;
1814 	}
1815 
1816 	pin->gpiod = gpiod;
1817 	pin->ena_gpio_invert = config->ena_gpio_invert;
1818 	list_add(&pin->list, &regulator_ena_gpio_list);
1819 
1820 update_ena_gpio_to_rdev:
1821 	pin->request_count++;
1822 	rdev->ena_pin = pin;
1823 	return 0;
1824 }
1825 
1826 static void regulator_ena_gpio_free(struct regulator_dev *rdev)
1827 {
1828 	struct regulator_enable_gpio *pin, *n;
1829 
1830 	if (!rdev->ena_pin)
1831 		return;
1832 
1833 	/* Free the GPIO only in case of no use */
1834 	list_for_each_entry_safe(pin, n, &regulator_ena_gpio_list, list) {
1835 		if (pin->gpiod == rdev->ena_pin->gpiod) {
1836 			if (pin->request_count <= 1) {
1837 				pin->request_count = 0;
1838 				gpiod_put(pin->gpiod);
1839 				list_del(&pin->list);
1840 				kfree(pin);
1841 				rdev->ena_pin = NULL;
1842 				return;
1843 			} else {
1844 				pin->request_count--;
1845 			}
1846 		}
1847 	}
1848 }
1849 
1850 /**
1851  * regulator_ena_gpio_ctrl - balance enable_count of each GPIO and actual GPIO pin control
1852  * @rdev: regulator_dev structure
1853  * @enable: enable GPIO at initial use?
1854  *
1855  * GPIO is enabled in case of initial use. (enable_count is 0)
1856  * GPIO is disabled when it is not shared any more. (enable_count <= 1)
1857  */
1858 static int regulator_ena_gpio_ctrl(struct regulator_dev *rdev, bool enable)
1859 {
1860 	struct regulator_enable_gpio *pin = rdev->ena_pin;
1861 
1862 	if (!pin)
1863 		return -EINVAL;
1864 
1865 	if (enable) {
1866 		/* Enable GPIO at initial use */
1867 		if (pin->enable_count == 0)
1868 			gpiod_set_value_cansleep(pin->gpiod,
1869 						 !pin->ena_gpio_invert);
1870 
1871 		pin->enable_count++;
1872 	} else {
1873 		if (pin->enable_count > 1) {
1874 			pin->enable_count--;
1875 			return 0;
1876 		}
1877 
1878 		/* Disable GPIO if not used */
1879 		if (pin->enable_count <= 1) {
1880 			gpiod_set_value_cansleep(pin->gpiod,
1881 						 pin->ena_gpio_invert);
1882 			pin->enable_count = 0;
1883 		}
1884 	}
1885 
1886 	return 0;
1887 }
1888 
1889 /**
1890  * _regulator_enable_delay - a delay helper function
1891  * @delay: time to delay in microseconds
1892  *
1893  * Delay for the requested amount of time as per the guidelines in:
1894  *
1895  *     Documentation/timers/timers-howto.txt
1896  *
1897  * The assumption here is that regulators will never be enabled in
1898  * atomic context and therefore sleeping functions can be used.
1899  */
1900 static void _regulator_enable_delay(unsigned int delay)
1901 {
1902 	unsigned int ms = delay / 1000;
1903 	unsigned int us = delay % 1000;
1904 
1905 	if (ms > 0) {
1906 		/*
1907 		 * For small enough values, handle super-millisecond
1908 		 * delays in the usleep_range() call below.
1909 		 */
1910 		if (ms < 20)
1911 			us += ms * 1000;
1912 		else
1913 			msleep(ms);
1914 	}
1915 
1916 	/*
1917 	 * Give the scheduler some room to coalesce with any other
1918 	 * wakeup sources. For delays shorter than 10 us, don't even
1919 	 * bother setting up high-resolution timers and just busy-
1920 	 * loop.
1921 	 */
1922 	if (us >= 10)
1923 		usleep_range(us, us + 100);
1924 	else
1925 		udelay(us);
1926 }
1927 
1928 static int _regulator_do_enable(struct regulator_dev *rdev)
1929 {
1930 	int ret, delay;
1931 
1932 	/* Query before enabling in case configuration dependent.  */
1933 	ret = _regulator_get_enable_time(rdev);
1934 	if (ret >= 0) {
1935 		delay = ret;
1936 	} else {
1937 		rdev_warn(rdev, "enable_time() failed: %d\n", ret);
1938 		delay = 0;
1939 	}
1940 
1941 	trace_regulator_enable(rdev_get_name(rdev));
1942 
1943 	if (rdev->desc->off_on_delay) {
1944 		/* if needed, keep a distance of off_on_delay from last time
1945 		 * this regulator was disabled.
1946 		 */
1947 		unsigned long start_jiffy = jiffies;
1948 		unsigned long intended, max_delay, remaining;
1949 
1950 		max_delay = usecs_to_jiffies(rdev->desc->off_on_delay);
1951 		intended = rdev->last_off_jiffy + max_delay;
1952 
1953 		if (time_before(start_jiffy, intended)) {
1954 			/* calc remaining jiffies to deal with one-time
1955 			 * timer wrapping.
1956 			 * in case of multiple timer wrapping, either it can be
1957 			 * detected by out-of-range remaining, or it cannot be
1958 			 * detected and we gets a panelty of
1959 			 * _regulator_enable_delay().
1960 			 */
1961 			remaining = intended - start_jiffy;
1962 			if (remaining <= max_delay)
1963 				_regulator_enable_delay(
1964 						jiffies_to_usecs(remaining));
1965 		}
1966 	}
1967 
1968 	if (rdev->ena_pin) {
1969 		if (!rdev->ena_gpio_state) {
1970 			ret = regulator_ena_gpio_ctrl(rdev, true);
1971 			if (ret < 0)
1972 				return ret;
1973 			rdev->ena_gpio_state = 1;
1974 		}
1975 	} else if (rdev->desc->ops->enable) {
1976 		ret = rdev->desc->ops->enable(rdev);
1977 		if (ret < 0)
1978 			return ret;
1979 	} else {
1980 		return -EINVAL;
1981 	}
1982 
1983 	/* Allow the regulator to ramp; it would be useful to extend
1984 	 * this for bulk operations so that the regulators can ramp
1985 	 * together.  */
1986 	trace_regulator_enable_delay(rdev_get_name(rdev));
1987 
1988 	_regulator_enable_delay(delay);
1989 
1990 	trace_regulator_enable_complete(rdev_get_name(rdev));
1991 
1992 	return 0;
1993 }
1994 
1995 /* locks held by regulator_enable() */
1996 static int _regulator_enable(struct regulator_dev *rdev)
1997 {
1998 	int ret;
1999 
2000 	lockdep_assert_held_once(&rdev->mutex);
2001 
2002 	/* check voltage and requested load before enabling */
2003 	if (rdev->constraints &&
2004 	    (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS))
2005 		drms_uA_update(rdev);
2006 
2007 	if (rdev->use_count == 0) {
2008 		/* The regulator may on if it's not switchable or left on */
2009 		ret = _regulator_is_enabled(rdev);
2010 		if (ret == -EINVAL || ret == 0) {
2011 			if (!_regulator_can_change_status(rdev))
2012 				return -EPERM;
2013 
2014 			ret = _regulator_do_enable(rdev);
2015 			if (ret < 0)
2016 				return ret;
2017 
2018 		} else if (ret < 0) {
2019 			rdev_err(rdev, "is_enabled() failed: %d\n", ret);
2020 			return ret;
2021 		}
2022 		/* Fallthrough on positive return values - already enabled */
2023 	}
2024 
2025 	rdev->use_count++;
2026 
2027 	return 0;
2028 }
2029 
2030 /**
2031  * regulator_enable - enable regulator output
2032  * @regulator: regulator source
2033  *
2034  * Request that the regulator be enabled with the regulator output at
2035  * the predefined voltage or current value.  Calls to regulator_enable()
2036  * must be balanced with calls to regulator_disable().
2037  *
2038  * NOTE: the output value can be set by other drivers, boot loader or may be
2039  * hardwired in the regulator.
2040  */
2041 int regulator_enable(struct regulator *regulator)
2042 {
2043 	struct regulator_dev *rdev = regulator->rdev;
2044 	int ret = 0;
2045 
2046 	if (regulator->always_on)
2047 		return 0;
2048 
2049 	if (rdev->supply) {
2050 		ret = regulator_enable(rdev->supply);
2051 		if (ret != 0)
2052 			return ret;
2053 	}
2054 
2055 	mutex_lock(&rdev->mutex);
2056 	ret = _regulator_enable(rdev);
2057 	mutex_unlock(&rdev->mutex);
2058 
2059 	if (ret != 0 && rdev->supply)
2060 		regulator_disable(rdev->supply);
2061 
2062 	return ret;
2063 }
2064 EXPORT_SYMBOL_GPL(regulator_enable);
2065 
2066 static int _regulator_do_disable(struct regulator_dev *rdev)
2067 {
2068 	int ret;
2069 
2070 	trace_regulator_disable(rdev_get_name(rdev));
2071 
2072 	if (rdev->ena_pin) {
2073 		if (rdev->ena_gpio_state) {
2074 			ret = regulator_ena_gpio_ctrl(rdev, false);
2075 			if (ret < 0)
2076 				return ret;
2077 			rdev->ena_gpio_state = 0;
2078 		}
2079 
2080 	} else if (rdev->desc->ops->disable) {
2081 		ret = rdev->desc->ops->disable(rdev);
2082 		if (ret != 0)
2083 			return ret;
2084 	}
2085 
2086 	/* cares about last_off_jiffy only if off_on_delay is required by
2087 	 * device.
2088 	 */
2089 	if (rdev->desc->off_on_delay)
2090 		rdev->last_off_jiffy = jiffies;
2091 
2092 	trace_regulator_disable_complete(rdev_get_name(rdev));
2093 
2094 	return 0;
2095 }
2096 
2097 /* locks held by regulator_disable() */
2098 static int _regulator_disable(struct regulator_dev *rdev)
2099 {
2100 	int ret = 0;
2101 
2102 	lockdep_assert_held_once(&rdev->mutex);
2103 
2104 	if (WARN(rdev->use_count <= 0,
2105 		 "unbalanced disables for %s\n", rdev_get_name(rdev)))
2106 		return -EIO;
2107 
2108 	/* are we the last user and permitted to disable ? */
2109 	if (rdev->use_count == 1 &&
2110 	    (rdev->constraints && !rdev->constraints->always_on)) {
2111 
2112 		/* we are last user */
2113 		if (_regulator_can_change_status(rdev)) {
2114 			ret = _notifier_call_chain(rdev,
2115 						   REGULATOR_EVENT_PRE_DISABLE,
2116 						   NULL);
2117 			if (ret & NOTIFY_STOP_MASK)
2118 				return -EINVAL;
2119 
2120 			ret = _regulator_do_disable(rdev);
2121 			if (ret < 0) {
2122 				rdev_err(rdev, "failed to disable\n");
2123 				_notifier_call_chain(rdev,
2124 						REGULATOR_EVENT_ABORT_DISABLE,
2125 						NULL);
2126 				return ret;
2127 			}
2128 			_notifier_call_chain(rdev, REGULATOR_EVENT_DISABLE,
2129 					NULL);
2130 		}
2131 
2132 		rdev->use_count = 0;
2133 	} else if (rdev->use_count > 1) {
2134 
2135 		if (rdev->constraints &&
2136 			(rdev->constraints->valid_ops_mask &
2137 			REGULATOR_CHANGE_DRMS))
2138 			drms_uA_update(rdev);
2139 
2140 		rdev->use_count--;
2141 	}
2142 
2143 	return ret;
2144 }
2145 
2146 /**
2147  * regulator_disable - disable regulator output
2148  * @regulator: regulator source
2149  *
2150  * Disable the regulator output voltage or current.  Calls to
2151  * regulator_enable() must be balanced with calls to
2152  * regulator_disable().
2153  *
2154  * NOTE: this will only disable the regulator output if no other consumer
2155  * devices have it enabled, the regulator device supports disabling and
2156  * machine constraints permit this operation.
2157  */
2158 int regulator_disable(struct regulator *regulator)
2159 {
2160 	struct regulator_dev *rdev = regulator->rdev;
2161 	int ret = 0;
2162 
2163 	if (regulator->always_on)
2164 		return 0;
2165 
2166 	mutex_lock(&rdev->mutex);
2167 	ret = _regulator_disable(rdev);
2168 	mutex_unlock(&rdev->mutex);
2169 
2170 	if (ret == 0 && rdev->supply)
2171 		regulator_disable(rdev->supply);
2172 
2173 	return ret;
2174 }
2175 EXPORT_SYMBOL_GPL(regulator_disable);
2176 
2177 /* locks held by regulator_force_disable() */
2178 static int _regulator_force_disable(struct regulator_dev *rdev)
2179 {
2180 	int ret = 0;
2181 
2182 	lockdep_assert_held_once(&rdev->mutex);
2183 
2184 	ret = _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
2185 			REGULATOR_EVENT_PRE_DISABLE, NULL);
2186 	if (ret & NOTIFY_STOP_MASK)
2187 		return -EINVAL;
2188 
2189 	ret = _regulator_do_disable(rdev);
2190 	if (ret < 0) {
2191 		rdev_err(rdev, "failed to force disable\n");
2192 		_notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
2193 				REGULATOR_EVENT_ABORT_DISABLE, NULL);
2194 		return ret;
2195 	}
2196 
2197 	_notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
2198 			REGULATOR_EVENT_DISABLE, NULL);
2199 
2200 	return 0;
2201 }
2202 
2203 /**
2204  * regulator_force_disable - force disable regulator output
2205  * @regulator: regulator source
2206  *
2207  * Forcibly disable the regulator output voltage or current.
2208  * NOTE: this *will* disable the regulator output even if other consumer
2209  * devices have it enabled. This should be used for situations when device
2210  * damage will likely occur if the regulator is not disabled (e.g. over temp).
2211  */
2212 int regulator_force_disable(struct regulator *regulator)
2213 {
2214 	struct regulator_dev *rdev = regulator->rdev;
2215 	int ret;
2216 
2217 	mutex_lock(&rdev->mutex);
2218 	regulator->uA_load = 0;
2219 	ret = _regulator_force_disable(regulator->rdev);
2220 	mutex_unlock(&rdev->mutex);
2221 
2222 	if (rdev->supply)
2223 		while (rdev->open_count--)
2224 			regulator_disable(rdev->supply);
2225 
2226 	return ret;
2227 }
2228 EXPORT_SYMBOL_GPL(regulator_force_disable);
2229 
2230 static void regulator_disable_work(struct work_struct *work)
2231 {
2232 	struct regulator_dev *rdev = container_of(work, struct regulator_dev,
2233 						  disable_work.work);
2234 	int count, i, ret;
2235 
2236 	mutex_lock(&rdev->mutex);
2237 
2238 	BUG_ON(!rdev->deferred_disables);
2239 
2240 	count = rdev->deferred_disables;
2241 	rdev->deferred_disables = 0;
2242 
2243 	for (i = 0; i < count; i++) {
2244 		ret = _regulator_disable(rdev);
2245 		if (ret != 0)
2246 			rdev_err(rdev, "Deferred disable failed: %d\n", ret);
2247 	}
2248 
2249 	mutex_unlock(&rdev->mutex);
2250 
2251 	if (rdev->supply) {
2252 		for (i = 0; i < count; i++) {
2253 			ret = regulator_disable(rdev->supply);
2254 			if (ret != 0) {
2255 				rdev_err(rdev,
2256 					 "Supply disable failed: %d\n", ret);
2257 			}
2258 		}
2259 	}
2260 }
2261 
2262 /**
2263  * regulator_disable_deferred - disable regulator output with delay
2264  * @regulator: regulator source
2265  * @ms: miliseconds until the regulator is disabled
2266  *
2267  * Execute regulator_disable() on the regulator after a delay.  This
2268  * is intended for use with devices that require some time to quiesce.
2269  *
2270  * NOTE: this will only disable the regulator output if no other consumer
2271  * devices have it enabled, the regulator device supports disabling and
2272  * machine constraints permit this operation.
2273  */
2274 int regulator_disable_deferred(struct regulator *regulator, int ms)
2275 {
2276 	struct regulator_dev *rdev = regulator->rdev;
2277 	int ret;
2278 
2279 	if (regulator->always_on)
2280 		return 0;
2281 
2282 	if (!ms)
2283 		return regulator_disable(regulator);
2284 
2285 	mutex_lock(&rdev->mutex);
2286 	rdev->deferred_disables++;
2287 	mutex_unlock(&rdev->mutex);
2288 
2289 	ret = queue_delayed_work(system_power_efficient_wq,
2290 				 &rdev->disable_work,
2291 				 msecs_to_jiffies(ms));
2292 	if (ret < 0)
2293 		return ret;
2294 	else
2295 		return 0;
2296 }
2297 EXPORT_SYMBOL_GPL(regulator_disable_deferred);
2298 
2299 static int _regulator_is_enabled(struct regulator_dev *rdev)
2300 {
2301 	/* A GPIO control always takes precedence */
2302 	if (rdev->ena_pin)
2303 		return rdev->ena_gpio_state;
2304 
2305 	/* If we don't know then assume that the regulator is always on */
2306 	if (!rdev->desc->ops->is_enabled)
2307 		return 1;
2308 
2309 	return rdev->desc->ops->is_enabled(rdev);
2310 }
2311 
2312 /**
2313  * regulator_is_enabled - is the regulator output enabled
2314  * @regulator: regulator source
2315  *
2316  * Returns positive if the regulator driver backing the source/client
2317  * has requested that the device be enabled, zero if it hasn't, else a
2318  * negative errno code.
2319  *
2320  * Note that the device backing this regulator handle can have multiple
2321  * users, so it might be enabled even if regulator_enable() was never
2322  * called for this particular source.
2323  */
2324 int regulator_is_enabled(struct regulator *regulator)
2325 {
2326 	int ret;
2327 
2328 	if (regulator->always_on)
2329 		return 1;
2330 
2331 	mutex_lock(&regulator->rdev->mutex);
2332 	ret = _regulator_is_enabled(regulator->rdev);
2333 	mutex_unlock(&regulator->rdev->mutex);
2334 
2335 	return ret;
2336 }
2337 EXPORT_SYMBOL_GPL(regulator_is_enabled);
2338 
2339 /**
2340  * regulator_can_change_voltage - check if regulator can change voltage
2341  * @regulator: regulator source
2342  *
2343  * Returns positive if the regulator driver backing the source/client
2344  * can change its voltage, false otherwise. Useful for detecting fixed
2345  * or dummy regulators and disabling voltage change logic in the client
2346  * driver.
2347  */
2348 int regulator_can_change_voltage(struct regulator *regulator)
2349 {
2350 	struct regulator_dev	*rdev = regulator->rdev;
2351 
2352 	if (rdev->constraints &&
2353 	    (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
2354 		if (rdev->desc->n_voltages - rdev->desc->linear_min_sel > 1)
2355 			return 1;
2356 
2357 		if (rdev->desc->continuous_voltage_range &&
2358 		    rdev->constraints->min_uV && rdev->constraints->max_uV &&
2359 		    rdev->constraints->min_uV != rdev->constraints->max_uV)
2360 			return 1;
2361 	}
2362 
2363 	return 0;
2364 }
2365 EXPORT_SYMBOL_GPL(regulator_can_change_voltage);
2366 
2367 /**
2368  * regulator_count_voltages - count regulator_list_voltage() selectors
2369  * @regulator: regulator source
2370  *
2371  * Returns number of selectors, or negative errno.  Selectors are
2372  * numbered starting at zero, and typically correspond to bitfields
2373  * in hardware registers.
2374  */
2375 int regulator_count_voltages(struct regulator *regulator)
2376 {
2377 	struct regulator_dev	*rdev = regulator->rdev;
2378 
2379 	if (rdev->desc->n_voltages)
2380 		return rdev->desc->n_voltages;
2381 
2382 	if (!rdev->supply)
2383 		return -EINVAL;
2384 
2385 	return regulator_count_voltages(rdev->supply);
2386 }
2387 EXPORT_SYMBOL_GPL(regulator_count_voltages);
2388 
2389 /**
2390  * regulator_list_voltage - enumerate supported voltages
2391  * @regulator: regulator source
2392  * @selector: identify voltage to list
2393  * Context: can sleep
2394  *
2395  * Returns a voltage that can be passed to @regulator_set_voltage(),
2396  * zero if this selector code can't be used on this system, or a
2397  * negative errno.
2398  */
2399 int regulator_list_voltage(struct regulator *regulator, unsigned selector)
2400 {
2401 	struct regulator_dev *rdev = regulator->rdev;
2402 	const struct regulator_ops *ops = rdev->desc->ops;
2403 	int ret;
2404 
2405 	if (rdev->desc->fixed_uV && rdev->desc->n_voltages == 1 && !selector)
2406 		return rdev->desc->fixed_uV;
2407 
2408 	if (ops->list_voltage) {
2409 		if (selector >= rdev->desc->n_voltages)
2410 			return -EINVAL;
2411 		mutex_lock(&rdev->mutex);
2412 		ret = ops->list_voltage(rdev, selector);
2413 		mutex_unlock(&rdev->mutex);
2414 	} else if (rdev->supply) {
2415 		ret = regulator_list_voltage(rdev->supply, selector);
2416 	} else {
2417 		return -EINVAL;
2418 	}
2419 
2420 	if (ret > 0) {
2421 		if (ret < rdev->constraints->min_uV)
2422 			ret = 0;
2423 		else if (ret > rdev->constraints->max_uV)
2424 			ret = 0;
2425 	}
2426 
2427 	return ret;
2428 }
2429 EXPORT_SYMBOL_GPL(regulator_list_voltage);
2430 
2431 /**
2432  * regulator_get_regmap - get the regulator's register map
2433  * @regulator: regulator source
2434  *
2435  * Returns the register map for the given regulator, or an ERR_PTR value
2436  * if the regulator doesn't use regmap.
2437  */
2438 struct regmap *regulator_get_regmap(struct regulator *regulator)
2439 {
2440 	struct regmap *map = regulator->rdev->regmap;
2441 
2442 	return map ? map : ERR_PTR(-EOPNOTSUPP);
2443 }
2444 
2445 /**
2446  * regulator_get_hardware_vsel_register - get the HW voltage selector register
2447  * @regulator: regulator source
2448  * @vsel_reg: voltage selector register, output parameter
2449  * @vsel_mask: mask for voltage selector bitfield, output parameter
2450  *
2451  * Returns the hardware register offset and bitmask used for setting the
2452  * regulator voltage. This might be useful when configuring voltage-scaling
2453  * hardware or firmware that can make I2C requests behind the kernel's back,
2454  * for example.
2455  *
2456  * On success, the output parameters @vsel_reg and @vsel_mask are filled in
2457  * and 0 is returned, otherwise a negative errno is returned.
2458  */
2459 int regulator_get_hardware_vsel_register(struct regulator *regulator,
2460 					 unsigned *vsel_reg,
2461 					 unsigned *vsel_mask)
2462 {
2463 	struct regulator_dev *rdev = regulator->rdev;
2464 	const struct regulator_ops *ops = rdev->desc->ops;
2465 
2466 	if (ops->set_voltage_sel != regulator_set_voltage_sel_regmap)
2467 		return -EOPNOTSUPP;
2468 
2469 	 *vsel_reg = rdev->desc->vsel_reg;
2470 	 *vsel_mask = rdev->desc->vsel_mask;
2471 
2472 	 return 0;
2473 }
2474 EXPORT_SYMBOL_GPL(regulator_get_hardware_vsel_register);
2475 
2476 /**
2477  * regulator_list_hardware_vsel - get the HW-specific register value for a selector
2478  * @regulator: regulator source
2479  * @selector: identify voltage to list
2480  *
2481  * Converts the selector to a hardware-specific voltage selector that can be
2482  * directly written to the regulator registers. The address of the voltage
2483  * register can be determined by calling @regulator_get_hardware_vsel_register.
2484  *
2485  * On error a negative errno is returned.
2486  */
2487 int regulator_list_hardware_vsel(struct regulator *regulator,
2488 				 unsigned selector)
2489 {
2490 	struct regulator_dev *rdev = regulator->rdev;
2491 	const struct regulator_ops *ops = rdev->desc->ops;
2492 
2493 	if (selector >= rdev->desc->n_voltages)
2494 		return -EINVAL;
2495 	if (ops->set_voltage_sel != regulator_set_voltage_sel_regmap)
2496 		return -EOPNOTSUPP;
2497 
2498 	return selector;
2499 }
2500 EXPORT_SYMBOL_GPL(regulator_list_hardware_vsel);
2501 
2502 /**
2503  * regulator_get_linear_step - return the voltage step size between VSEL values
2504  * @regulator: regulator source
2505  *
2506  * Returns the voltage step size between VSEL values for linear
2507  * regulators, or return 0 if the regulator isn't a linear regulator.
2508  */
2509 unsigned int regulator_get_linear_step(struct regulator *regulator)
2510 {
2511 	struct regulator_dev *rdev = regulator->rdev;
2512 
2513 	return rdev->desc->uV_step;
2514 }
2515 EXPORT_SYMBOL_GPL(regulator_get_linear_step);
2516 
2517 /**
2518  * regulator_is_supported_voltage - check if a voltage range can be supported
2519  *
2520  * @regulator: Regulator to check.
2521  * @min_uV: Minimum required voltage in uV.
2522  * @max_uV: Maximum required voltage in uV.
2523  *
2524  * Returns a boolean or a negative error code.
2525  */
2526 int regulator_is_supported_voltage(struct regulator *regulator,
2527 				   int min_uV, int max_uV)
2528 {
2529 	struct regulator_dev *rdev = regulator->rdev;
2530 	int i, voltages, ret;
2531 
2532 	/* If we can't change voltage check the current voltage */
2533 	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
2534 		ret = regulator_get_voltage(regulator);
2535 		if (ret >= 0)
2536 			return min_uV <= ret && ret <= max_uV;
2537 		else
2538 			return ret;
2539 	}
2540 
2541 	/* Any voltage within constrains range is fine? */
2542 	if (rdev->desc->continuous_voltage_range)
2543 		return min_uV >= rdev->constraints->min_uV &&
2544 				max_uV <= rdev->constraints->max_uV;
2545 
2546 	ret = regulator_count_voltages(regulator);
2547 	if (ret < 0)
2548 		return ret;
2549 	voltages = ret;
2550 
2551 	for (i = 0; i < voltages; i++) {
2552 		ret = regulator_list_voltage(regulator, i);
2553 
2554 		if (ret >= min_uV && ret <= max_uV)
2555 			return 1;
2556 	}
2557 
2558 	return 0;
2559 }
2560 EXPORT_SYMBOL_GPL(regulator_is_supported_voltage);
2561 
2562 static int _regulator_call_set_voltage(struct regulator_dev *rdev,
2563 				       int min_uV, int max_uV,
2564 				       unsigned *selector)
2565 {
2566 	struct pre_voltage_change_data data;
2567 	int ret;
2568 
2569 	data.old_uV = _regulator_get_voltage(rdev);
2570 	data.min_uV = min_uV;
2571 	data.max_uV = max_uV;
2572 	ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE,
2573 				   &data);
2574 	if (ret & NOTIFY_STOP_MASK)
2575 		return -EINVAL;
2576 
2577 	ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV, selector);
2578 	if (ret >= 0)
2579 		return ret;
2580 
2581 	_notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE,
2582 			     (void *)data.old_uV);
2583 
2584 	return ret;
2585 }
2586 
2587 static int _regulator_call_set_voltage_sel(struct regulator_dev *rdev,
2588 					   int uV, unsigned selector)
2589 {
2590 	struct pre_voltage_change_data data;
2591 	int ret;
2592 
2593 	data.old_uV = _regulator_get_voltage(rdev);
2594 	data.min_uV = uV;
2595 	data.max_uV = uV;
2596 	ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE,
2597 				   &data);
2598 	if (ret & NOTIFY_STOP_MASK)
2599 		return -EINVAL;
2600 
2601 	ret = rdev->desc->ops->set_voltage_sel(rdev, selector);
2602 	if (ret >= 0)
2603 		return ret;
2604 
2605 	_notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE,
2606 			     (void *)data.old_uV);
2607 
2608 	return ret;
2609 }
2610 
2611 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
2612 				     int min_uV, int max_uV)
2613 {
2614 	int ret;
2615 	int delay = 0;
2616 	int best_val = 0;
2617 	unsigned int selector;
2618 	int old_selector = -1;
2619 
2620 	trace_regulator_set_voltage(rdev_get_name(rdev), min_uV, max_uV);
2621 
2622 	min_uV += rdev->constraints->uV_offset;
2623 	max_uV += rdev->constraints->uV_offset;
2624 
2625 	/*
2626 	 * If we can't obtain the old selector there is not enough
2627 	 * info to call set_voltage_time_sel().
2628 	 */
2629 	if (_regulator_is_enabled(rdev) &&
2630 	    rdev->desc->ops->set_voltage_time_sel &&
2631 	    rdev->desc->ops->get_voltage_sel) {
2632 		old_selector = rdev->desc->ops->get_voltage_sel(rdev);
2633 		if (old_selector < 0)
2634 			return old_selector;
2635 	}
2636 
2637 	if (rdev->desc->ops->set_voltage) {
2638 		ret = _regulator_call_set_voltage(rdev, min_uV, max_uV,
2639 						  &selector);
2640 
2641 		if (ret >= 0) {
2642 			if (rdev->desc->ops->list_voltage)
2643 				best_val = rdev->desc->ops->list_voltage(rdev,
2644 									 selector);
2645 			else
2646 				best_val = _regulator_get_voltage(rdev);
2647 		}
2648 
2649 	} else if (rdev->desc->ops->set_voltage_sel) {
2650 		if (rdev->desc->ops->map_voltage) {
2651 			ret = rdev->desc->ops->map_voltage(rdev, min_uV,
2652 							   max_uV);
2653 		} else {
2654 			if (rdev->desc->ops->list_voltage ==
2655 			    regulator_list_voltage_linear)
2656 				ret = regulator_map_voltage_linear(rdev,
2657 								min_uV, max_uV);
2658 			else if (rdev->desc->ops->list_voltage ==
2659 				 regulator_list_voltage_linear_range)
2660 				ret = regulator_map_voltage_linear_range(rdev,
2661 								min_uV, max_uV);
2662 			else
2663 				ret = regulator_map_voltage_iterate(rdev,
2664 								min_uV, max_uV);
2665 		}
2666 
2667 		if (ret >= 0) {
2668 			best_val = rdev->desc->ops->list_voltage(rdev, ret);
2669 			if (min_uV <= best_val && max_uV >= best_val) {
2670 				selector = ret;
2671 				if (old_selector == selector)
2672 					ret = 0;
2673 				else
2674 					ret = _regulator_call_set_voltage_sel(
2675 						rdev, best_val, selector);
2676 			} else {
2677 				ret = -EINVAL;
2678 			}
2679 		}
2680 	} else {
2681 		ret = -EINVAL;
2682 	}
2683 
2684 	/* Call set_voltage_time_sel if successfully obtained old_selector */
2685 	if (ret == 0 && !rdev->constraints->ramp_disable && old_selector >= 0
2686 		&& old_selector != selector) {
2687 
2688 		delay = rdev->desc->ops->set_voltage_time_sel(rdev,
2689 						old_selector, selector);
2690 		if (delay < 0) {
2691 			rdev_warn(rdev, "set_voltage_time_sel() failed: %d\n",
2692 				  delay);
2693 			delay = 0;
2694 		}
2695 
2696 		/* Insert any necessary delays */
2697 		if (delay >= 1000) {
2698 			mdelay(delay / 1000);
2699 			udelay(delay % 1000);
2700 		} else if (delay) {
2701 			udelay(delay);
2702 		}
2703 	}
2704 
2705 	if (ret == 0 && best_val >= 0) {
2706 		unsigned long data = best_val;
2707 
2708 		_notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE,
2709 				     (void *)data);
2710 	}
2711 
2712 	trace_regulator_set_voltage_complete(rdev_get_name(rdev), best_val);
2713 
2714 	return ret;
2715 }
2716 
2717 /**
2718  * regulator_set_voltage - set regulator output voltage
2719  * @regulator: regulator source
2720  * @min_uV: Minimum required voltage in uV
2721  * @max_uV: Maximum acceptable voltage in uV
2722  *
2723  * Sets a voltage regulator to the desired output voltage. This can be set
2724  * during any regulator state. IOW, regulator can be disabled or enabled.
2725  *
2726  * If the regulator is enabled then the voltage will change to the new value
2727  * immediately otherwise if the regulator is disabled the regulator will
2728  * output at the new voltage when enabled.
2729  *
2730  * NOTE: If the regulator is shared between several devices then the lowest
2731  * request voltage that meets the system constraints will be used.
2732  * Regulator system constraints must be set for this regulator before
2733  * calling this function otherwise this call will fail.
2734  */
2735 int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
2736 {
2737 	struct regulator_dev *rdev = regulator->rdev;
2738 	int ret = 0;
2739 	int old_min_uV, old_max_uV;
2740 	int current_uV;
2741 
2742 	mutex_lock(&rdev->mutex);
2743 
2744 	/* If we're setting the same range as last time the change
2745 	 * should be a noop (some cpufreq implementations use the same
2746 	 * voltage for multiple frequencies, for example).
2747 	 */
2748 	if (regulator->min_uV == min_uV && regulator->max_uV == max_uV)
2749 		goto out;
2750 
2751 	/* If we're trying to set a range that overlaps the current voltage,
2752 	 * return successfully even though the regulator does not support
2753 	 * changing the voltage.
2754 	 */
2755 	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
2756 		current_uV = _regulator_get_voltage(rdev);
2757 		if (min_uV <= current_uV && current_uV <= max_uV) {
2758 			regulator->min_uV = min_uV;
2759 			regulator->max_uV = max_uV;
2760 			goto out;
2761 		}
2762 	}
2763 
2764 	/* sanity check */
2765 	if (!rdev->desc->ops->set_voltage &&
2766 	    !rdev->desc->ops->set_voltage_sel) {
2767 		ret = -EINVAL;
2768 		goto out;
2769 	}
2770 
2771 	/* constraints check */
2772 	ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
2773 	if (ret < 0)
2774 		goto out;
2775 
2776 	/* restore original values in case of error */
2777 	old_min_uV = regulator->min_uV;
2778 	old_max_uV = regulator->max_uV;
2779 	regulator->min_uV = min_uV;
2780 	regulator->max_uV = max_uV;
2781 
2782 	ret = regulator_check_consumers(rdev, &min_uV, &max_uV);
2783 	if (ret < 0)
2784 		goto out2;
2785 
2786 	ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
2787 	if (ret < 0)
2788 		goto out2;
2789 
2790 out:
2791 	mutex_unlock(&rdev->mutex);
2792 	return ret;
2793 out2:
2794 	regulator->min_uV = old_min_uV;
2795 	regulator->max_uV = old_max_uV;
2796 	mutex_unlock(&rdev->mutex);
2797 	return ret;
2798 }
2799 EXPORT_SYMBOL_GPL(regulator_set_voltage);
2800 
2801 /**
2802  * regulator_set_voltage_time - get raise/fall time
2803  * @regulator: regulator source
2804  * @old_uV: starting voltage in microvolts
2805  * @new_uV: target voltage in microvolts
2806  *
2807  * Provided with the starting and ending voltage, this function attempts to
2808  * calculate the time in microseconds required to rise or fall to this new
2809  * voltage.
2810  */
2811 int regulator_set_voltage_time(struct regulator *regulator,
2812 			       int old_uV, int new_uV)
2813 {
2814 	struct regulator_dev *rdev = regulator->rdev;
2815 	const struct regulator_ops *ops = rdev->desc->ops;
2816 	int old_sel = -1;
2817 	int new_sel = -1;
2818 	int voltage;
2819 	int i;
2820 
2821 	/* Currently requires operations to do this */
2822 	if (!ops->list_voltage || !ops->set_voltage_time_sel
2823 	    || !rdev->desc->n_voltages)
2824 		return -EINVAL;
2825 
2826 	for (i = 0; i < rdev->desc->n_voltages; i++) {
2827 		/* We only look for exact voltage matches here */
2828 		voltage = regulator_list_voltage(regulator, i);
2829 		if (voltage < 0)
2830 			return -EINVAL;
2831 		if (voltage == 0)
2832 			continue;
2833 		if (voltage == old_uV)
2834 			old_sel = i;
2835 		if (voltage == new_uV)
2836 			new_sel = i;
2837 	}
2838 
2839 	if (old_sel < 0 || new_sel < 0)
2840 		return -EINVAL;
2841 
2842 	return ops->set_voltage_time_sel(rdev, old_sel, new_sel);
2843 }
2844 EXPORT_SYMBOL_GPL(regulator_set_voltage_time);
2845 
2846 /**
2847  * regulator_set_voltage_time_sel - get raise/fall time
2848  * @rdev: regulator source device
2849  * @old_selector: selector for starting voltage
2850  * @new_selector: selector for target voltage
2851  *
2852  * Provided with the starting and target voltage selectors, this function
2853  * returns time in microseconds required to rise or fall to this new voltage
2854  *
2855  * Drivers providing ramp_delay in regulation_constraints can use this as their
2856  * set_voltage_time_sel() operation.
2857  */
2858 int regulator_set_voltage_time_sel(struct regulator_dev *rdev,
2859 				   unsigned int old_selector,
2860 				   unsigned int new_selector)
2861 {
2862 	unsigned int ramp_delay = 0;
2863 	int old_volt, new_volt;
2864 
2865 	if (rdev->constraints->ramp_delay)
2866 		ramp_delay = rdev->constraints->ramp_delay;
2867 	else if (rdev->desc->ramp_delay)
2868 		ramp_delay = rdev->desc->ramp_delay;
2869 
2870 	if (ramp_delay == 0) {
2871 		rdev_warn(rdev, "ramp_delay not set\n");
2872 		return 0;
2873 	}
2874 
2875 	/* sanity check */
2876 	if (!rdev->desc->ops->list_voltage)
2877 		return -EINVAL;
2878 
2879 	old_volt = rdev->desc->ops->list_voltage(rdev, old_selector);
2880 	new_volt = rdev->desc->ops->list_voltage(rdev, new_selector);
2881 
2882 	return DIV_ROUND_UP(abs(new_volt - old_volt), ramp_delay);
2883 }
2884 EXPORT_SYMBOL_GPL(regulator_set_voltage_time_sel);
2885 
2886 /**
2887  * regulator_sync_voltage - re-apply last regulator output voltage
2888  * @regulator: regulator source
2889  *
2890  * Re-apply the last configured voltage.  This is intended to be used
2891  * where some external control source the consumer is cooperating with
2892  * has caused the configured voltage to change.
2893  */
2894 int regulator_sync_voltage(struct regulator *regulator)
2895 {
2896 	struct regulator_dev *rdev = regulator->rdev;
2897 	int ret, min_uV, max_uV;
2898 
2899 	mutex_lock(&rdev->mutex);
2900 
2901 	if (!rdev->desc->ops->set_voltage &&
2902 	    !rdev->desc->ops->set_voltage_sel) {
2903 		ret = -EINVAL;
2904 		goto out;
2905 	}
2906 
2907 	/* This is only going to work if we've had a voltage configured. */
2908 	if (!regulator->min_uV && !regulator->max_uV) {
2909 		ret = -EINVAL;
2910 		goto out;
2911 	}
2912 
2913 	min_uV = regulator->min_uV;
2914 	max_uV = regulator->max_uV;
2915 
2916 	/* This should be a paranoia check... */
2917 	ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
2918 	if (ret < 0)
2919 		goto out;
2920 
2921 	ret = regulator_check_consumers(rdev, &min_uV, &max_uV);
2922 	if (ret < 0)
2923 		goto out;
2924 
2925 	ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
2926 
2927 out:
2928 	mutex_unlock(&rdev->mutex);
2929 	return ret;
2930 }
2931 EXPORT_SYMBOL_GPL(regulator_sync_voltage);
2932 
2933 static int _regulator_get_voltage(struct regulator_dev *rdev)
2934 {
2935 	int sel, ret;
2936 
2937 	if (rdev->desc->ops->get_voltage_sel) {
2938 		sel = rdev->desc->ops->get_voltage_sel(rdev);
2939 		if (sel < 0)
2940 			return sel;
2941 		ret = rdev->desc->ops->list_voltage(rdev, sel);
2942 	} else if (rdev->desc->ops->get_voltage) {
2943 		ret = rdev->desc->ops->get_voltage(rdev);
2944 	} else if (rdev->desc->ops->list_voltage) {
2945 		ret = rdev->desc->ops->list_voltage(rdev, 0);
2946 	} else if (rdev->desc->fixed_uV && (rdev->desc->n_voltages == 1)) {
2947 		ret = rdev->desc->fixed_uV;
2948 	} else if (rdev->supply) {
2949 		ret = regulator_get_voltage(rdev->supply);
2950 	} else {
2951 		return -EINVAL;
2952 	}
2953 
2954 	if (ret < 0)
2955 		return ret;
2956 	return ret - rdev->constraints->uV_offset;
2957 }
2958 
2959 /**
2960  * regulator_get_voltage - get regulator output voltage
2961  * @regulator: regulator source
2962  *
2963  * This returns the current regulator voltage in uV.
2964  *
2965  * NOTE: If the regulator is disabled it will return the voltage value. This
2966  * function should not be used to determine regulator state.
2967  */
2968 int regulator_get_voltage(struct regulator *regulator)
2969 {
2970 	int ret;
2971 
2972 	mutex_lock(&regulator->rdev->mutex);
2973 
2974 	ret = _regulator_get_voltage(regulator->rdev);
2975 
2976 	mutex_unlock(&regulator->rdev->mutex);
2977 
2978 	return ret;
2979 }
2980 EXPORT_SYMBOL_GPL(regulator_get_voltage);
2981 
2982 /**
2983  * regulator_set_current_limit - set regulator output current limit
2984  * @regulator: regulator source
2985  * @min_uA: Minimum supported current in uA
2986  * @max_uA: Maximum supported current in uA
2987  *
2988  * Sets current sink to the desired output current. This can be set during
2989  * any regulator state. IOW, regulator can be disabled or enabled.
2990  *
2991  * If the regulator is enabled then the current will change to the new value
2992  * immediately otherwise if the regulator is disabled the regulator will
2993  * output at the new current when enabled.
2994  *
2995  * NOTE: Regulator system constraints must be set for this regulator before
2996  * calling this function otherwise this call will fail.
2997  */
2998 int regulator_set_current_limit(struct regulator *regulator,
2999 			       int min_uA, int max_uA)
3000 {
3001 	struct regulator_dev *rdev = regulator->rdev;
3002 	int ret;
3003 
3004 	mutex_lock(&rdev->mutex);
3005 
3006 	/* sanity check */
3007 	if (!rdev->desc->ops->set_current_limit) {
3008 		ret = -EINVAL;
3009 		goto out;
3010 	}
3011 
3012 	/* constraints check */
3013 	ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
3014 	if (ret < 0)
3015 		goto out;
3016 
3017 	ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
3018 out:
3019 	mutex_unlock(&rdev->mutex);
3020 	return ret;
3021 }
3022 EXPORT_SYMBOL_GPL(regulator_set_current_limit);
3023 
3024 static int _regulator_get_current_limit(struct regulator_dev *rdev)
3025 {
3026 	int ret;
3027 
3028 	mutex_lock(&rdev->mutex);
3029 
3030 	/* sanity check */
3031 	if (!rdev->desc->ops->get_current_limit) {
3032 		ret = -EINVAL;
3033 		goto out;
3034 	}
3035 
3036 	ret = rdev->desc->ops->get_current_limit(rdev);
3037 out:
3038 	mutex_unlock(&rdev->mutex);
3039 	return ret;
3040 }
3041 
3042 /**
3043  * regulator_get_current_limit - get regulator output current
3044  * @regulator: regulator source
3045  *
3046  * This returns the current supplied by the specified current sink in uA.
3047  *
3048  * NOTE: If the regulator is disabled it will return the current value. This
3049  * function should not be used to determine regulator state.
3050  */
3051 int regulator_get_current_limit(struct regulator *regulator)
3052 {
3053 	return _regulator_get_current_limit(regulator->rdev);
3054 }
3055 EXPORT_SYMBOL_GPL(regulator_get_current_limit);
3056 
3057 /**
3058  * regulator_set_mode - set regulator operating mode
3059  * @regulator: regulator source
3060  * @mode: operating mode - one of the REGULATOR_MODE constants
3061  *
3062  * Set regulator operating mode to increase regulator efficiency or improve
3063  * regulation performance.
3064  *
3065  * NOTE: Regulator system constraints must be set for this regulator before
3066  * calling this function otherwise this call will fail.
3067  */
3068 int regulator_set_mode(struct regulator *regulator, unsigned int mode)
3069 {
3070 	struct regulator_dev *rdev = regulator->rdev;
3071 	int ret;
3072 	int regulator_curr_mode;
3073 
3074 	mutex_lock(&rdev->mutex);
3075 
3076 	/* sanity check */
3077 	if (!rdev->desc->ops->set_mode) {
3078 		ret = -EINVAL;
3079 		goto out;
3080 	}
3081 
3082 	/* return if the same mode is requested */
3083 	if (rdev->desc->ops->get_mode) {
3084 		regulator_curr_mode = rdev->desc->ops->get_mode(rdev);
3085 		if (regulator_curr_mode == mode) {
3086 			ret = 0;
3087 			goto out;
3088 		}
3089 	}
3090 
3091 	/* constraints check */
3092 	ret = regulator_mode_constrain(rdev, &mode);
3093 	if (ret < 0)
3094 		goto out;
3095 
3096 	ret = rdev->desc->ops->set_mode(rdev, mode);
3097 out:
3098 	mutex_unlock(&rdev->mutex);
3099 	return ret;
3100 }
3101 EXPORT_SYMBOL_GPL(regulator_set_mode);
3102 
3103 static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
3104 {
3105 	int ret;
3106 
3107 	mutex_lock(&rdev->mutex);
3108 
3109 	/* sanity check */
3110 	if (!rdev->desc->ops->get_mode) {
3111 		ret = -EINVAL;
3112 		goto out;
3113 	}
3114 
3115 	ret = rdev->desc->ops->get_mode(rdev);
3116 out:
3117 	mutex_unlock(&rdev->mutex);
3118 	return ret;
3119 }
3120 
3121 /**
3122  * regulator_get_mode - get regulator operating mode
3123  * @regulator: regulator source
3124  *
3125  * Get the current regulator operating mode.
3126  */
3127 unsigned int regulator_get_mode(struct regulator *regulator)
3128 {
3129 	return _regulator_get_mode(regulator->rdev);
3130 }
3131 EXPORT_SYMBOL_GPL(regulator_get_mode);
3132 
3133 /**
3134  * regulator_set_load - set regulator load
3135  * @regulator: regulator source
3136  * @uA_load: load current
3137  *
3138  * Notifies the regulator core of a new device load. This is then used by
3139  * DRMS (if enabled by constraints) to set the most efficient regulator
3140  * operating mode for the new regulator loading.
3141  *
3142  * Consumer devices notify their supply regulator of the maximum power
3143  * they will require (can be taken from device datasheet in the power
3144  * consumption tables) when they change operational status and hence power
3145  * state. Examples of operational state changes that can affect power
3146  * consumption are :-
3147  *
3148  *    o Device is opened / closed.
3149  *    o Device I/O is about to begin or has just finished.
3150  *    o Device is idling in between work.
3151  *
3152  * This information is also exported via sysfs to userspace.
3153  *
3154  * DRMS will sum the total requested load on the regulator and change
3155  * to the most efficient operating mode if platform constraints allow.
3156  *
3157  * On error a negative errno is returned.
3158  */
3159 int regulator_set_load(struct regulator *regulator, int uA_load)
3160 {
3161 	struct regulator_dev *rdev = regulator->rdev;
3162 	int ret;
3163 
3164 	mutex_lock(&rdev->mutex);
3165 	regulator->uA_load = uA_load;
3166 	ret = drms_uA_update(rdev);
3167 	mutex_unlock(&rdev->mutex);
3168 
3169 	return ret;
3170 }
3171 EXPORT_SYMBOL_GPL(regulator_set_load);
3172 
3173 /**
3174  * regulator_allow_bypass - allow the regulator to go into bypass mode
3175  *
3176  * @regulator: Regulator to configure
3177  * @enable: enable or disable bypass mode
3178  *
3179  * Allow the regulator to go into bypass mode if all other consumers
3180  * for the regulator also enable bypass mode and the machine
3181  * constraints allow this.  Bypass mode means that the regulator is
3182  * simply passing the input directly to the output with no regulation.
3183  */
3184 int regulator_allow_bypass(struct regulator *regulator, bool enable)
3185 {
3186 	struct regulator_dev *rdev = regulator->rdev;
3187 	int ret = 0;
3188 
3189 	if (!rdev->desc->ops->set_bypass)
3190 		return 0;
3191 
3192 	if (rdev->constraints &&
3193 	    !(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_BYPASS))
3194 		return 0;
3195 
3196 	mutex_lock(&rdev->mutex);
3197 
3198 	if (enable && !regulator->bypass) {
3199 		rdev->bypass_count++;
3200 
3201 		if (rdev->bypass_count == rdev->open_count) {
3202 			ret = rdev->desc->ops->set_bypass(rdev, enable);
3203 			if (ret != 0)
3204 				rdev->bypass_count--;
3205 		}
3206 
3207 	} else if (!enable && regulator->bypass) {
3208 		rdev->bypass_count--;
3209 
3210 		if (rdev->bypass_count != rdev->open_count) {
3211 			ret = rdev->desc->ops->set_bypass(rdev, enable);
3212 			if (ret != 0)
3213 				rdev->bypass_count++;
3214 		}
3215 	}
3216 
3217 	if (ret == 0)
3218 		regulator->bypass = enable;
3219 
3220 	mutex_unlock(&rdev->mutex);
3221 
3222 	return ret;
3223 }
3224 EXPORT_SYMBOL_GPL(regulator_allow_bypass);
3225 
3226 /**
3227  * regulator_register_notifier - register regulator event notifier
3228  * @regulator: regulator source
3229  * @nb: notifier block
3230  *
3231  * Register notifier block to receive regulator events.
3232  */
3233 int regulator_register_notifier(struct regulator *regulator,
3234 			      struct notifier_block *nb)
3235 {
3236 	return blocking_notifier_chain_register(&regulator->rdev->notifier,
3237 						nb);
3238 }
3239 EXPORT_SYMBOL_GPL(regulator_register_notifier);
3240 
3241 /**
3242  * regulator_unregister_notifier - unregister regulator event notifier
3243  * @regulator: regulator source
3244  * @nb: notifier block
3245  *
3246  * Unregister regulator event notifier block.
3247  */
3248 int regulator_unregister_notifier(struct regulator *regulator,
3249 				struct notifier_block *nb)
3250 {
3251 	return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
3252 						  nb);
3253 }
3254 EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
3255 
3256 /* notify regulator consumers and downstream regulator consumers.
3257  * Note mutex must be held by caller.
3258  */
3259 static int _notifier_call_chain(struct regulator_dev *rdev,
3260 				  unsigned long event, void *data)
3261 {
3262 	/* call rdev chain first */
3263 	return blocking_notifier_call_chain(&rdev->notifier, event, data);
3264 }
3265 
3266 /**
3267  * regulator_bulk_get - get multiple regulator consumers
3268  *
3269  * @dev:           Device to supply
3270  * @num_consumers: Number of consumers to register
3271  * @consumers:     Configuration of consumers; clients are stored here.
3272  *
3273  * @return 0 on success, an errno on failure.
3274  *
3275  * This helper function allows drivers to get several regulator
3276  * consumers in one operation.  If any of the regulators cannot be
3277  * acquired then any regulators that were allocated will be freed
3278  * before returning to the caller.
3279  */
3280 int regulator_bulk_get(struct device *dev, int num_consumers,
3281 		       struct regulator_bulk_data *consumers)
3282 {
3283 	int i;
3284 	int ret;
3285 
3286 	for (i = 0; i < num_consumers; i++)
3287 		consumers[i].consumer = NULL;
3288 
3289 	for (i = 0; i < num_consumers; i++) {
3290 		consumers[i].consumer = regulator_get(dev,
3291 						      consumers[i].supply);
3292 		if (IS_ERR(consumers[i].consumer)) {
3293 			ret = PTR_ERR(consumers[i].consumer);
3294 			dev_err(dev, "Failed to get supply '%s': %d\n",
3295 				consumers[i].supply, ret);
3296 			consumers[i].consumer = NULL;
3297 			goto err;
3298 		}
3299 	}
3300 
3301 	return 0;
3302 
3303 err:
3304 	while (--i >= 0)
3305 		regulator_put(consumers[i].consumer);
3306 
3307 	return ret;
3308 }
3309 EXPORT_SYMBOL_GPL(regulator_bulk_get);
3310 
3311 static void regulator_bulk_enable_async(void *data, async_cookie_t cookie)
3312 {
3313 	struct regulator_bulk_data *bulk = data;
3314 
3315 	bulk->ret = regulator_enable(bulk->consumer);
3316 }
3317 
3318 /**
3319  * regulator_bulk_enable - enable multiple regulator consumers
3320  *
3321  * @num_consumers: Number of consumers
3322  * @consumers:     Consumer data; clients are stored here.
3323  * @return         0 on success, an errno on failure
3324  *
3325  * This convenience API allows consumers to enable multiple regulator
3326  * clients in a single API call.  If any consumers cannot be enabled
3327  * then any others that were enabled will be disabled again prior to
3328  * return.
3329  */
3330 int regulator_bulk_enable(int num_consumers,
3331 			  struct regulator_bulk_data *consumers)
3332 {
3333 	ASYNC_DOMAIN_EXCLUSIVE(async_domain);
3334 	int i;
3335 	int ret = 0;
3336 
3337 	for (i = 0; i < num_consumers; i++) {
3338 		if (consumers[i].consumer->always_on)
3339 			consumers[i].ret = 0;
3340 		else
3341 			async_schedule_domain(regulator_bulk_enable_async,
3342 					      &consumers[i], &async_domain);
3343 	}
3344 
3345 	async_synchronize_full_domain(&async_domain);
3346 
3347 	/* If any consumer failed we need to unwind any that succeeded */
3348 	for (i = 0; i < num_consumers; i++) {
3349 		if (consumers[i].ret != 0) {
3350 			ret = consumers[i].ret;
3351 			goto err;
3352 		}
3353 	}
3354 
3355 	return 0;
3356 
3357 err:
3358 	for (i = 0; i < num_consumers; i++) {
3359 		if (consumers[i].ret < 0)
3360 			pr_err("Failed to enable %s: %d\n", consumers[i].supply,
3361 			       consumers[i].ret);
3362 		else
3363 			regulator_disable(consumers[i].consumer);
3364 	}
3365 
3366 	return ret;
3367 }
3368 EXPORT_SYMBOL_GPL(regulator_bulk_enable);
3369 
3370 /**
3371  * regulator_bulk_disable - disable multiple regulator consumers
3372  *
3373  * @num_consumers: Number of consumers
3374  * @consumers:     Consumer data; clients are stored here.
3375  * @return         0 on success, an errno on failure
3376  *
3377  * This convenience API allows consumers to disable multiple regulator
3378  * clients in a single API call.  If any consumers cannot be disabled
3379  * then any others that were disabled will be enabled again prior to
3380  * return.
3381  */
3382 int regulator_bulk_disable(int num_consumers,
3383 			   struct regulator_bulk_data *consumers)
3384 {
3385 	int i;
3386 	int ret, r;
3387 
3388 	for (i = num_consumers - 1; i >= 0; --i) {
3389 		ret = regulator_disable(consumers[i].consumer);
3390 		if (ret != 0)
3391 			goto err;
3392 	}
3393 
3394 	return 0;
3395 
3396 err:
3397 	pr_err("Failed to disable %s: %d\n", consumers[i].supply, ret);
3398 	for (++i; i < num_consumers; ++i) {
3399 		r = regulator_enable(consumers[i].consumer);
3400 		if (r != 0)
3401 			pr_err("Failed to reename %s: %d\n",
3402 			       consumers[i].supply, r);
3403 	}
3404 
3405 	return ret;
3406 }
3407 EXPORT_SYMBOL_GPL(regulator_bulk_disable);
3408 
3409 /**
3410  * regulator_bulk_force_disable - force disable multiple regulator consumers
3411  *
3412  * @num_consumers: Number of consumers
3413  * @consumers:     Consumer data; clients are stored here.
3414  * @return         0 on success, an errno on failure
3415  *
3416  * This convenience API allows consumers to forcibly disable multiple regulator
3417  * clients in a single API call.
3418  * NOTE: This should be used for situations when device damage will
3419  * likely occur if the regulators are not disabled (e.g. over temp).
3420  * Although regulator_force_disable function call for some consumers can
3421  * return error numbers, the function is called for all consumers.
3422  */
3423 int regulator_bulk_force_disable(int num_consumers,
3424 			   struct regulator_bulk_data *consumers)
3425 {
3426 	int i;
3427 	int ret;
3428 
3429 	for (i = 0; i < num_consumers; i++)
3430 		consumers[i].ret =
3431 			    regulator_force_disable(consumers[i].consumer);
3432 
3433 	for (i = 0; i < num_consumers; i++) {
3434 		if (consumers[i].ret != 0) {
3435 			ret = consumers[i].ret;
3436 			goto out;
3437 		}
3438 	}
3439 
3440 	return 0;
3441 out:
3442 	return ret;
3443 }
3444 EXPORT_SYMBOL_GPL(regulator_bulk_force_disable);
3445 
3446 /**
3447  * regulator_bulk_free - free multiple regulator consumers
3448  *
3449  * @num_consumers: Number of consumers
3450  * @consumers:     Consumer data; clients are stored here.
3451  *
3452  * This convenience API allows consumers to free multiple regulator
3453  * clients in a single API call.
3454  */
3455 void regulator_bulk_free(int num_consumers,
3456 			 struct regulator_bulk_data *consumers)
3457 {
3458 	int i;
3459 
3460 	for (i = 0; i < num_consumers; i++) {
3461 		regulator_put(consumers[i].consumer);
3462 		consumers[i].consumer = NULL;
3463 	}
3464 }
3465 EXPORT_SYMBOL_GPL(regulator_bulk_free);
3466 
3467 /**
3468  * regulator_notifier_call_chain - call regulator event notifier
3469  * @rdev: regulator source
3470  * @event: notifier block
3471  * @data: callback-specific data.
3472  *
3473  * Called by regulator drivers to notify clients a regulator event has
3474  * occurred. We also notify regulator clients downstream.
3475  * Note lock must be held by caller.
3476  */
3477 int regulator_notifier_call_chain(struct regulator_dev *rdev,
3478 				  unsigned long event, void *data)
3479 {
3480 	lockdep_assert_held_once(&rdev->mutex);
3481 
3482 	_notifier_call_chain(rdev, event, data);
3483 	return NOTIFY_DONE;
3484 
3485 }
3486 EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
3487 
3488 /**
3489  * regulator_mode_to_status - convert a regulator mode into a status
3490  *
3491  * @mode: Mode to convert
3492  *
3493  * Convert a regulator mode into a status.
3494  */
3495 int regulator_mode_to_status(unsigned int mode)
3496 {
3497 	switch (mode) {
3498 	case REGULATOR_MODE_FAST:
3499 		return REGULATOR_STATUS_FAST;
3500 	case REGULATOR_MODE_NORMAL:
3501 		return REGULATOR_STATUS_NORMAL;
3502 	case REGULATOR_MODE_IDLE:
3503 		return REGULATOR_STATUS_IDLE;
3504 	case REGULATOR_MODE_STANDBY:
3505 		return REGULATOR_STATUS_STANDBY;
3506 	default:
3507 		return REGULATOR_STATUS_UNDEFINED;
3508 	}
3509 }
3510 EXPORT_SYMBOL_GPL(regulator_mode_to_status);
3511 
3512 static struct attribute *regulator_dev_attrs[] = {
3513 	&dev_attr_name.attr,
3514 	&dev_attr_num_users.attr,
3515 	&dev_attr_type.attr,
3516 	&dev_attr_microvolts.attr,
3517 	&dev_attr_microamps.attr,
3518 	&dev_attr_opmode.attr,
3519 	&dev_attr_state.attr,
3520 	&dev_attr_status.attr,
3521 	&dev_attr_bypass.attr,
3522 	&dev_attr_requested_microamps.attr,
3523 	&dev_attr_min_microvolts.attr,
3524 	&dev_attr_max_microvolts.attr,
3525 	&dev_attr_min_microamps.attr,
3526 	&dev_attr_max_microamps.attr,
3527 	&dev_attr_suspend_standby_state.attr,
3528 	&dev_attr_suspend_mem_state.attr,
3529 	&dev_attr_suspend_disk_state.attr,
3530 	&dev_attr_suspend_standby_microvolts.attr,
3531 	&dev_attr_suspend_mem_microvolts.attr,
3532 	&dev_attr_suspend_disk_microvolts.attr,
3533 	&dev_attr_suspend_standby_mode.attr,
3534 	&dev_attr_suspend_mem_mode.attr,
3535 	&dev_attr_suspend_disk_mode.attr,
3536 	NULL
3537 };
3538 
3539 /*
3540  * To avoid cluttering sysfs (and memory) with useless state, only
3541  * create attributes that can be meaningfully displayed.
3542  */
3543 static umode_t regulator_attr_is_visible(struct kobject *kobj,
3544 					 struct attribute *attr, int idx)
3545 {
3546 	struct device *dev = kobj_to_dev(kobj);
3547 	struct regulator_dev *rdev = container_of(dev, struct regulator_dev, dev);
3548 	const struct regulator_ops *ops = rdev->desc->ops;
3549 	umode_t mode = attr->mode;
3550 
3551 	/* these three are always present */
3552 	if (attr == &dev_attr_name.attr ||
3553 	    attr == &dev_attr_num_users.attr ||
3554 	    attr == &dev_attr_type.attr)
3555 		return mode;
3556 
3557 	/* some attributes need specific methods to be displayed */
3558 	if (attr == &dev_attr_microvolts.attr) {
3559 		if ((ops->get_voltage && ops->get_voltage(rdev) >= 0) ||
3560 		    (ops->get_voltage_sel && ops->get_voltage_sel(rdev) >= 0) ||
3561 		    (ops->list_voltage && ops->list_voltage(rdev, 0) >= 0) ||
3562 		    (rdev->desc->fixed_uV && rdev->desc->n_voltages == 1))
3563 			return mode;
3564 		return 0;
3565 	}
3566 
3567 	if (attr == &dev_attr_microamps.attr)
3568 		return ops->get_current_limit ? mode : 0;
3569 
3570 	if (attr == &dev_attr_opmode.attr)
3571 		return ops->get_mode ? mode : 0;
3572 
3573 	if (attr == &dev_attr_state.attr)
3574 		return (rdev->ena_pin || ops->is_enabled) ? mode : 0;
3575 
3576 	if (attr == &dev_attr_status.attr)
3577 		return ops->get_status ? mode : 0;
3578 
3579 	if (attr == &dev_attr_bypass.attr)
3580 		return ops->get_bypass ? mode : 0;
3581 
3582 	/* some attributes are type-specific */
3583 	if (attr == &dev_attr_requested_microamps.attr)
3584 		return rdev->desc->type == REGULATOR_CURRENT ? mode : 0;
3585 
3586 	/* constraints need specific supporting methods */
3587 	if (attr == &dev_attr_min_microvolts.attr ||
3588 	    attr == &dev_attr_max_microvolts.attr)
3589 		return (ops->set_voltage || ops->set_voltage_sel) ? mode : 0;
3590 
3591 	if (attr == &dev_attr_min_microamps.attr ||
3592 	    attr == &dev_attr_max_microamps.attr)
3593 		return ops->set_current_limit ? mode : 0;
3594 
3595 	if (attr == &dev_attr_suspend_standby_state.attr ||
3596 	    attr == &dev_attr_suspend_mem_state.attr ||
3597 	    attr == &dev_attr_suspend_disk_state.attr)
3598 		return mode;
3599 
3600 	if (attr == &dev_attr_suspend_standby_microvolts.attr ||
3601 	    attr == &dev_attr_suspend_mem_microvolts.attr ||
3602 	    attr == &dev_attr_suspend_disk_microvolts.attr)
3603 		return ops->set_suspend_voltage ? mode : 0;
3604 
3605 	if (attr == &dev_attr_suspend_standby_mode.attr ||
3606 	    attr == &dev_attr_suspend_mem_mode.attr ||
3607 	    attr == &dev_attr_suspend_disk_mode.attr)
3608 		return ops->set_suspend_mode ? mode : 0;
3609 
3610 	return mode;
3611 }
3612 
3613 static const struct attribute_group regulator_dev_group = {
3614 	.attrs = regulator_dev_attrs,
3615 	.is_visible = regulator_attr_is_visible,
3616 };
3617 
3618 static const struct attribute_group *regulator_dev_groups[] = {
3619 	&regulator_dev_group,
3620 	NULL
3621 };
3622 
3623 static void regulator_dev_release(struct device *dev)
3624 {
3625 	struct regulator_dev *rdev = dev_get_drvdata(dev);
3626 
3627 	kfree(rdev->constraints);
3628 	of_node_put(rdev->dev.of_node);
3629 	kfree(rdev);
3630 }
3631 
3632 static struct class regulator_class = {
3633 	.name = "regulator",
3634 	.dev_release = regulator_dev_release,
3635 	.dev_groups = regulator_dev_groups,
3636 };
3637 
3638 static void rdev_init_debugfs(struct regulator_dev *rdev)
3639 {
3640 	struct device *parent = rdev->dev.parent;
3641 	const char *rname = rdev_get_name(rdev);
3642 	char name[NAME_MAX];
3643 
3644 	/* Avoid duplicate debugfs directory names */
3645 	if (parent && rname == rdev->desc->name) {
3646 		snprintf(name, sizeof(name), "%s-%s", dev_name(parent),
3647 			 rname);
3648 		rname = name;
3649 	}
3650 
3651 	rdev->debugfs = debugfs_create_dir(rname, debugfs_root);
3652 	if (!rdev->debugfs) {
3653 		rdev_warn(rdev, "Failed to create debugfs directory\n");
3654 		return;
3655 	}
3656 
3657 	debugfs_create_u32("use_count", 0444, rdev->debugfs,
3658 			   &rdev->use_count);
3659 	debugfs_create_u32("open_count", 0444, rdev->debugfs,
3660 			   &rdev->open_count);
3661 	debugfs_create_u32("bypass_count", 0444, rdev->debugfs,
3662 			   &rdev->bypass_count);
3663 }
3664 
3665 /**
3666  * regulator_register - register regulator
3667  * @regulator_desc: regulator to register
3668  * @cfg: runtime configuration for regulator
3669  *
3670  * Called by regulator drivers to register a regulator.
3671  * Returns a valid pointer to struct regulator_dev on success
3672  * or an ERR_PTR() on error.
3673  */
3674 struct regulator_dev *
3675 regulator_register(const struct regulator_desc *regulator_desc,
3676 		   const struct regulator_config *cfg)
3677 {
3678 	const struct regulation_constraints *constraints = NULL;
3679 	const struct regulator_init_data *init_data;
3680 	struct regulator_config *config = NULL;
3681 	static atomic_t regulator_no = ATOMIC_INIT(-1);
3682 	struct regulator_dev *rdev;
3683 	struct device *dev;
3684 	int ret, i;
3685 
3686 	if (regulator_desc == NULL || cfg == NULL)
3687 		return ERR_PTR(-EINVAL);
3688 
3689 	dev = cfg->dev;
3690 	WARN_ON(!dev);
3691 
3692 	if (regulator_desc->name == NULL || regulator_desc->ops == NULL)
3693 		return ERR_PTR(-EINVAL);
3694 
3695 	if (regulator_desc->type != REGULATOR_VOLTAGE &&
3696 	    regulator_desc->type != REGULATOR_CURRENT)
3697 		return ERR_PTR(-EINVAL);
3698 
3699 	/* Only one of each should be implemented */
3700 	WARN_ON(regulator_desc->ops->get_voltage &&
3701 		regulator_desc->ops->get_voltage_sel);
3702 	WARN_ON(regulator_desc->ops->set_voltage &&
3703 		regulator_desc->ops->set_voltage_sel);
3704 
3705 	/* If we're using selectors we must implement list_voltage. */
3706 	if (regulator_desc->ops->get_voltage_sel &&
3707 	    !regulator_desc->ops->list_voltage) {
3708 		return ERR_PTR(-EINVAL);
3709 	}
3710 	if (regulator_desc->ops->set_voltage_sel &&
3711 	    !regulator_desc->ops->list_voltage) {
3712 		return ERR_PTR(-EINVAL);
3713 	}
3714 
3715 	rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
3716 	if (rdev == NULL)
3717 		return ERR_PTR(-ENOMEM);
3718 
3719 	/*
3720 	 * Duplicate the config so the driver could override it after
3721 	 * parsing init data.
3722 	 */
3723 	config = kmemdup(cfg, sizeof(*cfg), GFP_KERNEL);
3724 	if (config == NULL) {
3725 		kfree(rdev);
3726 		return ERR_PTR(-ENOMEM);
3727 	}
3728 
3729 	init_data = regulator_of_get_init_data(dev, regulator_desc, config,
3730 					       &rdev->dev.of_node);
3731 	if (!init_data) {
3732 		init_data = config->init_data;
3733 		rdev->dev.of_node = of_node_get(config->of_node);
3734 	}
3735 
3736 	mutex_lock(&regulator_list_mutex);
3737 
3738 	mutex_init(&rdev->mutex);
3739 	rdev->reg_data = config->driver_data;
3740 	rdev->owner = regulator_desc->owner;
3741 	rdev->desc = regulator_desc;
3742 	if (config->regmap)
3743 		rdev->regmap = config->regmap;
3744 	else if (dev_get_regmap(dev, NULL))
3745 		rdev->regmap = dev_get_regmap(dev, NULL);
3746 	else if (dev->parent)
3747 		rdev->regmap = dev_get_regmap(dev->parent, NULL);
3748 	INIT_LIST_HEAD(&rdev->consumer_list);
3749 	INIT_LIST_HEAD(&rdev->list);
3750 	BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
3751 	INIT_DELAYED_WORK(&rdev->disable_work, regulator_disable_work);
3752 
3753 	/* preform any regulator specific init */
3754 	if (init_data && init_data->regulator_init) {
3755 		ret = init_data->regulator_init(rdev->reg_data);
3756 		if (ret < 0)
3757 			goto clean;
3758 	}
3759 
3760 	/* register with sysfs */
3761 	rdev->dev.class = &regulator_class;
3762 	rdev->dev.parent = dev;
3763 	dev_set_name(&rdev->dev, "regulator.%lu",
3764 		    (unsigned long) atomic_inc_return(&regulator_no));
3765 	ret = device_register(&rdev->dev);
3766 	if (ret != 0) {
3767 		put_device(&rdev->dev);
3768 		goto clean;
3769 	}
3770 
3771 	dev_set_drvdata(&rdev->dev, rdev);
3772 
3773 	if ((config->ena_gpio || config->ena_gpio_initialized) &&
3774 	    gpio_is_valid(config->ena_gpio)) {
3775 		ret = regulator_ena_gpio_request(rdev, config);
3776 		if (ret != 0) {
3777 			rdev_err(rdev, "Failed to request enable GPIO%d: %d\n",
3778 				 config->ena_gpio, ret);
3779 			goto wash;
3780 		}
3781 	}
3782 
3783 	/* set regulator constraints */
3784 	if (init_data)
3785 		constraints = &init_data->constraints;
3786 
3787 	ret = set_machine_constraints(rdev, constraints);
3788 	if (ret < 0)
3789 		goto scrub;
3790 
3791 	if (init_data && init_data->supply_regulator)
3792 		rdev->supply_name = init_data->supply_regulator;
3793 	else if (regulator_desc->supply_name)
3794 		rdev->supply_name = regulator_desc->supply_name;
3795 
3796 	/* add consumers devices */
3797 	if (init_data) {
3798 		for (i = 0; i < init_data->num_consumer_supplies; i++) {
3799 			ret = set_consumer_device_supply(rdev,
3800 				init_data->consumer_supplies[i].dev_name,
3801 				init_data->consumer_supplies[i].supply);
3802 			if (ret < 0) {
3803 				dev_err(dev, "Failed to set supply %s\n",
3804 					init_data->consumer_supplies[i].supply);
3805 				goto unset_supplies;
3806 			}
3807 		}
3808 	}
3809 
3810 	list_add(&rdev->list, &regulator_list);
3811 
3812 	rdev_init_debugfs(rdev);
3813 out:
3814 	mutex_unlock(&regulator_list_mutex);
3815 	kfree(config);
3816 	return rdev;
3817 
3818 unset_supplies:
3819 	unset_regulator_supplies(rdev);
3820 
3821 scrub:
3822 	regulator_ena_gpio_free(rdev);
3823 	kfree(rdev->constraints);
3824 wash:
3825 	device_unregister(&rdev->dev);
3826 	/* device core frees rdev */
3827 	rdev = ERR_PTR(ret);
3828 	goto out;
3829 
3830 clean:
3831 	kfree(rdev);
3832 	rdev = ERR_PTR(ret);
3833 	goto out;
3834 }
3835 EXPORT_SYMBOL_GPL(regulator_register);
3836 
3837 /**
3838  * regulator_unregister - unregister regulator
3839  * @rdev: regulator to unregister
3840  *
3841  * Called by regulator drivers to unregister a regulator.
3842  */
3843 void regulator_unregister(struct regulator_dev *rdev)
3844 {
3845 	if (rdev == NULL)
3846 		return;
3847 
3848 	if (rdev->supply) {
3849 		while (rdev->use_count--)
3850 			regulator_disable(rdev->supply);
3851 		regulator_put(rdev->supply);
3852 	}
3853 	mutex_lock(&regulator_list_mutex);
3854 	debugfs_remove_recursive(rdev->debugfs);
3855 	flush_work(&rdev->disable_work.work);
3856 	WARN_ON(rdev->open_count);
3857 	unset_regulator_supplies(rdev);
3858 	list_del(&rdev->list);
3859 	mutex_unlock(&regulator_list_mutex);
3860 	regulator_ena_gpio_free(rdev);
3861 	device_unregister(&rdev->dev);
3862 }
3863 EXPORT_SYMBOL_GPL(regulator_unregister);
3864 
3865 /**
3866  * regulator_suspend_prepare - prepare regulators for system wide suspend
3867  * @state: system suspend state
3868  *
3869  * Configure each regulator with it's suspend operating parameters for state.
3870  * This will usually be called by machine suspend code prior to supending.
3871  */
3872 int regulator_suspend_prepare(suspend_state_t state)
3873 {
3874 	struct regulator_dev *rdev;
3875 	int ret = 0;
3876 
3877 	/* ON is handled by regulator active state */
3878 	if (state == PM_SUSPEND_ON)
3879 		return -EINVAL;
3880 
3881 	mutex_lock(&regulator_list_mutex);
3882 	list_for_each_entry(rdev, &regulator_list, list) {
3883 
3884 		mutex_lock(&rdev->mutex);
3885 		ret = suspend_prepare(rdev, state);
3886 		mutex_unlock(&rdev->mutex);
3887 
3888 		if (ret < 0) {
3889 			rdev_err(rdev, "failed to prepare\n");
3890 			goto out;
3891 		}
3892 	}
3893 out:
3894 	mutex_unlock(&regulator_list_mutex);
3895 	return ret;
3896 }
3897 EXPORT_SYMBOL_GPL(regulator_suspend_prepare);
3898 
3899 /**
3900  * regulator_suspend_finish - resume regulators from system wide suspend
3901  *
3902  * Turn on regulators that might be turned off by regulator_suspend_prepare
3903  * and that should be turned on according to the regulators properties.
3904  */
3905 int regulator_suspend_finish(void)
3906 {
3907 	struct regulator_dev *rdev;
3908 	int ret = 0, error;
3909 
3910 	mutex_lock(&regulator_list_mutex);
3911 	list_for_each_entry(rdev, &regulator_list, list) {
3912 		mutex_lock(&rdev->mutex);
3913 		if (rdev->use_count > 0  || rdev->constraints->always_on) {
3914 			if (!_regulator_is_enabled(rdev)) {
3915 				error = _regulator_do_enable(rdev);
3916 				if (error)
3917 					ret = error;
3918 			}
3919 		} else {
3920 			if (!have_full_constraints())
3921 				goto unlock;
3922 			if (!_regulator_is_enabled(rdev))
3923 				goto unlock;
3924 
3925 			error = _regulator_do_disable(rdev);
3926 			if (error)
3927 				ret = error;
3928 		}
3929 unlock:
3930 		mutex_unlock(&rdev->mutex);
3931 	}
3932 	mutex_unlock(&regulator_list_mutex);
3933 	return ret;
3934 }
3935 EXPORT_SYMBOL_GPL(regulator_suspend_finish);
3936 
3937 /**
3938  * regulator_has_full_constraints - the system has fully specified constraints
3939  *
3940  * Calling this function will cause the regulator API to disable all
3941  * regulators which have a zero use count and don't have an always_on
3942  * constraint in a late_initcall.
3943  *
3944  * The intention is that this will become the default behaviour in a
3945  * future kernel release so users are encouraged to use this facility
3946  * now.
3947  */
3948 void regulator_has_full_constraints(void)
3949 {
3950 	has_full_constraints = 1;
3951 }
3952 EXPORT_SYMBOL_GPL(regulator_has_full_constraints);
3953 
3954 /**
3955  * rdev_get_drvdata - get rdev regulator driver data
3956  * @rdev: regulator
3957  *
3958  * Get rdev regulator driver private data. This call can be used in the
3959  * regulator driver context.
3960  */
3961 void *rdev_get_drvdata(struct regulator_dev *rdev)
3962 {
3963 	return rdev->reg_data;
3964 }
3965 EXPORT_SYMBOL_GPL(rdev_get_drvdata);
3966 
3967 /**
3968  * regulator_get_drvdata - get regulator driver data
3969  * @regulator: regulator
3970  *
3971  * Get regulator driver private data. This call can be used in the consumer
3972  * driver context when non API regulator specific functions need to be called.
3973  */
3974 void *regulator_get_drvdata(struct regulator *regulator)
3975 {
3976 	return regulator->rdev->reg_data;
3977 }
3978 EXPORT_SYMBOL_GPL(regulator_get_drvdata);
3979 
3980 /**
3981  * regulator_set_drvdata - set regulator driver data
3982  * @regulator: regulator
3983  * @data: data
3984  */
3985 void regulator_set_drvdata(struct regulator *regulator, void *data)
3986 {
3987 	regulator->rdev->reg_data = data;
3988 }
3989 EXPORT_SYMBOL_GPL(regulator_set_drvdata);
3990 
3991 /**
3992  * regulator_get_id - get regulator ID
3993  * @rdev: regulator
3994  */
3995 int rdev_get_id(struct regulator_dev *rdev)
3996 {
3997 	return rdev->desc->id;
3998 }
3999 EXPORT_SYMBOL_GPL(rdev_get_id);
4000 
4001 struct device *rdev_get_dev(struct regulator_dev *rdev)
4002 {
4003 	return &rdev->dev;
4004 }
4005 EXPORT_SYMBOL_GPL(rdev_get_dev);
4006 
4007 void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
4008 {
4009 	return reg_init_data->driver_data;
4010 }
4011 EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
4012 
4013 #ifdef CONFIG_DEBUG_FS
4014 static ssize_t supply_map_read_file(struct file *file, char __user *user_buf,
4015 				    size_t count, loff_t *ppos)
4016 {
4017 	char *buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
4018 	ssize_t len, ret = 0;
4019 	struct regulator_map *map;
4020 
4021 	if (!buf)
4022 		return -ENOMEM;
4023 
4024 	list_for_each_entry(map, &regulator_map_list, list) {
4025 		len = snprintf(buf + ret, PAGE_SIZE - ret,
4026 			       "%s -> %s.%s\n",
4027 			       rdev_get_name(map->regulator), map->dev_name,
4028 			       map->supply);
4029 		if (len >= 0)
4030 			ret += len;
4031 		if (ret > PAGE_SIZE) {
4032 			ret = PAGE_SIZE;
4033 			break;
4034 		}
4035 	}
4036 
4037 	ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
4038 
4039 	kfree(buf);
4040 
4041 	return ret;
4042 }
4043 #endif
4044 
4045 static const struct file_operations supply_map_fops = {
4046 #ifdef CONFIG_DEBUG_FS
4047 	.read = supply_map_read_file,
4048 	.llseek = default_llseek,
4049 #endif
4050 };
4051 
4052 #ifdef CONFIG_DEBUG_FS
4053 static void regulator_summary_show_subtree(struct seq_file *s,
4054 					   struct regulator_dev *rdev,
4055 					   int level)
4056 {
4057 	struct list_head *list = s->private;
4058 	struct regulator_dev *child;
4059 	struct regulation_constraints *c;
4060 	struct regulator *consumer;
4061 
4062 	if (!rdev)
4063 		return;
4064 
4065 	seq_printf(s, "%*s%-*s %3d %4d %6d ",
4066 		   level * 3 + 1, "",
4067 		   30 - level * 3, rdev_get_name(rdev),
4068 		   rdev->use_count, rdev->open_count, rdev->bypass_count);
4069 
4070 	seq_printf(s, "%5dmV ", _regulator_get_voltage(rdev) / 1000);
4071 	seq_printf(s, "%5dmA ", _regulator_get_current_limit(rdev) / 1000);
4072 
4073 	c = rdev->constraints;
4074 	if (c) {
4075 		switch (rdev->desc->type) {
4076 		case REGULATOR_VOLTAGE:
4077 			seq_printf(s, "%5dmV %5dmV ",
4078 				   c->min_uV / 1000, c->max_uV / 1000);
4079 			break;
4080 		case REGULATOR_CURRENT:
4081 			seq_printf(s, "%5dmA %5dmA ",
4082 				   c->min_uA / 1000, c->max_uA / 1000);
4083 			break;
4084 		}
4085 	}
4086 
4087 	seq_puts(s, "\n");
4088 
4089 	list_for_each_entry(consumer, &rdev->consumer_list, list) {
4090 		if (consumer->dev->class == &regulator_class)
4091 			continue;
4092 
4093 		seq_printf(s, "%*s%-*s ",
4094 			   (level + 1) * 3 + 1, "",
4095 			   30 - (level + 1) * 3, dev_name(consumer->dev));
4096 
4097 		switch (rdev->desc->type) {
4098 		case REGULATOR_VOLTAGE:
4099 			seq_printf(s, "%37dmV %5dmV",
4100 				   consumer->min_uV / 1000,
4101 				   consumer->max_uV / 1000);
4102 			break;
4103 		case REGULATOR_CURRENT:
4104 			break;
4105 		}
4106 
4107 		seq_puts(s, "\n");
4108 	}
4109 
4110 	list_for_each_entry(child, list, list) {
4111 		/* handle only non-root regulators supplied by current rdev */
4112 		if (!child->supply || child->supply->rdev != rdev)
4113 			continue;
4114 
4115 		regulator_summary_show_subtree(s, child, level + 1);
4116 	}
4117 }
4118 
4119 static int regulator_summary_show(struct seq_file *s, void *data)
4120 {
4121 	struct list_head *list = s->private;
4122 	struct regulator_dev *rdev;
4123 
4124 	seq_puts(s, " regulator                      use open bypass voltage current     min     max\n");
4125 	seq_puts(s, "-------------------------------------------------------------------------------\n");
4126 
4127 	mutex_lock(&regulator_list_mutex);
4128 
4129 	list_for_each_entry(rdev, list, list) {
4130 		if (rdev->supply)
4131 			continue;
4132 
4133 		regulator_summary_show_subtree(s, rdev, 0);
4134 	}
4135 
4136 	mutex_unlock(&regulator_list_mutex);
4137 
4138 	return 0;
4139 }
4140 
4141 static int regulator_summary_open(struct inode *inode, struct file *file)
4142 {
4143 	return single_open(file, regulator_summary_show, inode->i_private);
4144 }
4145 #endif
4146 
4147 static const struct file_operations regulator_summary_fops = {
4148 #ifdef CONFIG_DEBUG_FS
4149 	.open		= regulator_summary_open,
4150 	.read		= seq_read,
4151 	.llseek		= seq_lseek,
4152 	.release	= single_release,
4153 #endif
4154 };
4155 
4156 static int __init regulator_init(void)
4157 {
4158 	int ret;
4159 
4160 	ret = class_register(&regulator_class);
4161 
4162 	debugfs_root = debugfs_create_dir("regulator", NULL);
4163 	if (!debugfs_root)
4164 		pr_warn("regulator: Failed to create debugfs directory\n");
4165 
4166 	debugfs_create_file("supply_map", 0444, debugfs_root, NULL,
4167 			    &supply_map_fops);
4168 
4169 	debugfs_create_file("regulator_summary", 0444, debugfs_root,
4170 			    &regulator_list, &regulator_summary_fops);
4171 
4172 	regulator_dummy_init();
4173 
4174 	return ret;
4175 }
4176 
4177 /* init early to allow our consumers to complete system booting */
4178 core_initcall(regulator_init);
4179 
4180 static int __init regulator_late_cleanup(struct device *dev, void *data)
4181 {
4182 	struct regulator_dev *rdev = dev_to_rdev(dev);
4183 	const struct regulator_ops *ops = rdev->desc->ops;
4184 	struct regulation_constraints *c = rdev->constraints;
4185 	int enabled, ret;
4186 
4187 	if (c && c->always_on)
4188 		return 0;
4189 
4190 	if (c && !(c->valid_ops_mask & REGULATOR_CHANGE_STATUS))
4191 		return 0;
4192 
4193 	mutex_lock(&rdev->mutex);
4194 
4195 	if (rdev->use_count)
4196 		goto unlock;
4197 
4198 	/* If we can't read the status assume it's on. */
4199 	if (ops->is_enabled)
4200 		enabled = ops->is_enabled(rdev);
4201 	else
4202 		enabled = 1;
4203 
4204 	if (!enabled)
4205 		goto unlock;
4206 
4207 	if (have_full_constraints()) {
4208 		/* We log since this may kill the system if it goes
4209 		 * wrong. */
4210 		rdev_info(rdev, "disabling\n");
4211 		ret = _regulator_do_disable(rdev);
4212 		if (ret != 0)
4213 			rdev_err(rdev, "couldn't disable: %d\n", ret);
4214 	} else {
4215 		/* The intention is that in future we will
4216 		 * assume that full constraints are provided
4217 		 * so warn even if we aren't going to do
4218 		 * anything here.
4219 		 */
4220 		rdev_warn(rdev, "incomplete constraints, leaving on\n");
4221 	}
4222 
4223 unlock:
4224 	mutex_unlock(&rdev->mutex);
4225 
4226 	return 0;
4227 }
4228 
4229 static int __init regulator_init_complete(void)
4230 {
4231 	/*
4232 	 * Since DT doesn't provide an idiomatic mechanism for
4233 	 * enabling full constraints and since it's much more natural
4234 	 * with DT to provide them just assume that a DT enabled
4235 	 * system has full constraints.
4236 	 */
4237 	if (of_have_populated_dt())
4238 		has_full_constraints = true;
4239 
4240 	/* If we have a full configuration then disable any regulators
4241 	 * we have permission to change the status for and which are
4242 	 * not in use or always_on.  This is effectively the default
4243 	 * for DT and ACPI as they have full constraints.
4244 	 */
4245 	class_for_each_device(&regulator_class, NULL, NULL,
4246 			      regulator_late_cleanup);
4247 
4248 	return 0;
4249 }
4250 late_initcall_sync(regulator_init_complete);
4251