xref: /openbmc/linux/drivers/regulator/core.c (revision eb3fcf007fffe5830d815e713591f3e858f2a365)
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 (!r) {
1398 		if (ret == -ENODEV) {
1399 			/*
1400 			 * No supply was specified for this regulator and
1401 			 * there will never be one.
1402 			 */
1403 			return 0;
1404 		}
1405 
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) && rdev->supply) {
1426 		ret = regulator_enable(rdev->supply);
1427 		if (ret < 0) {
1428 			_regulator_put(rdev->supply);
1429 			return ret;
1430 		}
1431 	}
1432 
1433 	return 0;
1434 }
1435 
1436 /* Internal regulator request function */
1437 static struct regulator *_regulator_get(struct device *dev, const char *id,
1438 					bool exclusive, bool allow_dummy)
1439 {
1440 	struct regulator_dev *rdev;
1441 	struct regulator *regulator = ERR_PTR(-EPROBE_DEFER);
1442 	const char *devname = NULL;
1443 	int ret;
1444 
1445 	if (id == NULL) {
1446 		pr_err("get() with no identifier\n");
1447 		return ERR_PTR(-EINVAL);
1448 	}
1449 
1450 	if (dev)
1451 		devname = dev_name(dev);
1452 
1453 	if (have_full_constraints())
1454 		ret = -ENODEV;
1455 	else
1456 		ret = -EPROBE_DEFER;
1457 
1458 	mutex_lock(&regulator_list_mutex);
1459 
1460 	rdev = regulator_dev_lookup(dev, id, &ret);
1461 	if (rdev)
1462 		goto found;
1463 
1464 	regulator = ERR_PTR(ret);
1465 
1466 	/*
1467 	 * If we have return value from dev_lookup fail, we do not expect to
1468 	 * succeed, so, quit with appropriate error value
1469 	 */
1470 	if (ret && ret != -ENODEV)
1471 		goto out;
1472 
1473 	if (!devname)
1474 		devname = "deviceless";
1475 
1476 	/*
1477 	 * Assume that a regulator is physically present and enabled
1478 	 * even if it isn't hooked up and just provide a dummy.
1479 	 */
1480 	if (have_full_constraints() && allow_dummy) {
1481 		pr_warn("%s supply %s not found, using dummy regulator\n",
1482 			devname, id);
1483 
1484 		rdev = dummy_regulator_rdev;
1485 		goto found;
1486 	/* Don't log an error when called from regulator_get_optional() */
1487 	} else if (!have_full_constraints() || exclusive) {
1488 		dev_warn(dev, "dummy supplies not allowed\n");
1489 	}
1490 
1491 	mutex_unlock(&regulator_list_mutex);
1492 	return regulator;
1493 
1494 found:
1495 	if (rdev->exclusive) {
1496 		regulator = ERR_PTR(-EPERM);
1497 		goto out;
1498 	}
1499 
1500 	if (exclusive && rdev->open_count) {
1501 		regulator = ERR_PTR(-EBUSY);
1502 		goto out;
1503 	}
1504 
1505 	ret = regulator_resolve_supply(rdev);
1506 	if (ret < 0) {
1507 		regulator = ERR_PTR(ret);
1508 		goto out;
1509 	}
1510 
1511 	if (!try_module_get(rdev->owner))
1512 		goto out;
1513 
1514 	regulator = create_regulator(rdev, dev, id);
1515 	if (regulator == NULL) {
1516 		regulator = ERR_PTR(-ENOMEM);
1517 		module_put(rdev->owner);
1518 		goto out;
1519 	}
1520 
1521 	rdev->open_count++;
1522 	if (exclusive) {
1523 		rdev->exclusive = 1;
1524 
1525 		ret = _regulator_is_enabled(rdev);
1526 		if (ret > 0)
1527 			rdev->use_count = 1;
1528 		else
1529 			rdev->use_count = 0;
1530 	}
1531 
1532 out:
1533 	mutex_unlock(&regulator_list_mutex);
1534 
1535 	return regulator;
1536 }
1537 
1538 /**
1539  * regulator_get - lookup and obtain a reference to a regulator.
1540  * @dev: device for regulator "consumer"
1541  * @id: Supply name or regulator ID.
1542  *
1543  * Returns a struct regulator corresponding to the regulator producer,
1544  * or IS_ERR() condition containing errno.
1545  *
1546  * Use of supply names configured via regulator_set_device_supply() is
1547  * strongly encouraged.  It is recommended that the supply name used
1548  * should match the name used for the supply and/or the relevant
1549  * device pins in the datasheet.
1550  */
1551 struct regulator *regulator_get(struct device *dev, const char *id)
1552 {
1553 	return _regulator_get(dev, id, false, true);
1554 }
1555 EXPORT_SYMBOL_GPL(regulator_get);
1556 
1557 /**
1558  * regulator_get_exclusive - obtain exclusive access to a regulator.
1559  * @dev: device for regulator "consumer"
1560  * @id: Supply name or regulator ID.
1561  *
1562  * Returns a struct regulator corresponding to the regulator producer,
1563  * or IS_ERR() condition containing errno.  Other consumers will be
1564  * unable to obtain this regulator while this reference is held and the
1565  * use count for the regulator will be initialised to reflect the current
1566  * state of the regulator.
1567  *
1568  * This is intended for use by consumers which cannot tolerate shared
1569  * use of the regulator such as those which need to force the
1570  * regulator off for correct operation of the hardware they are
1571  * controlling.
1572  *
1573  * Use of supply names configured via regulator_set_device_supply() is
1574  * strongly encouraged.  It is recommended that the supply name used
1575  * should match the name used for the supply and/or the relevant
1576  * device pins in the datasheet.
1577  */
1578 struct regulator *regulator_get_exclusive(struct device *dev, const char *id)
1579 {
1580 	return _regulator_get(dev, id, true, false);
1581 }
1582 EXPORT_SYMBOL_GPL(regulator_get_exclusive);
1583 
1584 /**
1585  * regulator_get_optional - obtain optional access to a regulator.
1586  * @dev: device for regulator "consumer"
1587  * @id: Supply name or regulator ID.
1588  *
1589  * Returns a struct regulator corresponding to the regulator producer,
1590  * or IS_ERR() condition containing errno.
1591  *
1592  * This is intended for use by consumers for devices which can have
1593  * some supplies unconnected in normal use, such as some MMC devices.
1594  * It can allow the regulator core to provide stub supplies for other
1595  * supplies requested using normal regulator_get() calls without
1596  * disrupting the operation of drivers that can handle absent
1597  * supplies.
1598  *
1599  * Use of supply names configured via regulator_set_device_supply() is
1600  * strongly encouraged.  It is recommended that the supply name used
1601  * should match the name used for the supply and/or the relevant
1602  * device pins in the datasheet.
1603  */
1604 struct regulator *regulator_get_optional(struct device *dev, const char *id)
1605 {
1606 	return _regulator_get(dev, id, false, false);
1607 }
1608 EXPORT_SYMBOL_GPL(regulator_get_optional);
1609 
1610 /* regulator_list_mutex lock held by regulator_put() */
1611 static void _regulator_put(struct regulator *regulator)
1612 {
1613 	struct regulator_dev *rdev;
1614 
1615 	if (IS_ERR_OR_NULL(regulator))
1616 		return;
1617 
1618 	lockdep_assert_held_once(&regulator_list_mutex);
1619 
1620 	rdev = regulator->rdev;
1621 
1622 	debugfs_remove_recursive(regulator->debugfs);
1623 
1624 	/* remove any sysfs entries */
1625 	if (regulator->dev)
1626 		sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
1627 	mutex_lock(&rdev->mutex);
1628 	list_del(&regulator->list);
1629 
1630 	rdev->open_count--;
1631 	rdev->exclusive = 0;
1632 	mutex_unlock(&rdev->mutex);
1633 
1634 	kfree(regulator->supply_name);
1635 	kfree(regulator);
1636 
1637 	module_put(rdev->owner);
1638 }
1639 
1640 /**
1641  * regulator_put - "free" the regulator source
1642  * @regulator: regulator source
1643  *
1644  * Note: drivers must ensure that all regulator_enable calls made on this
1645  * regulator source are balanced by regulator_disable calls prior to calling
1646  * this function.
1647  */
1648 void regulator_put(struct regulator *regulator)
1649 {
1650 	mutex_lock(&regulator_list_mutex);
1651 	_regulator_put(regulator);
1652 	mutex_unlock(&regulator_list_mutex);
1653 }
1654 EXPORT_SYMBOL_GPL(regulator_put);
1655 
1656 /**
1657  * regulator_register_supply_alias - Provide device alias for supply lookup
1658  *
1659  * @dev: device that will be given as the regulator "consumer"
1660  * @id: Supply name or regulator ID
1661  * @alias_dev: device that should be used to lookup the supply
1662  * @alias_id: Supply name or regulator ID that should be used to lookup the
1663  * supply
1664  *
1665  * All lookups for id on dev will instead be conducted for alias_id on
1666  * alias_dev.
1667  */
1668 int regulator_register_supply_alias(struct device *dev, const char *id,
1669 				    struct device *alias_dev,
1670 				    const char *alias_id)
1671 {
1672 	struct regulator_supply_alias *map;
1673 
1674 	map = regulator_find_supply_alias(dev, id);
1675 	if (map)
1676 		return -EEXIST;
1677 
1678 	map = kzalloc(sizeof(struct regulator_supply_alias), GFP_KERNEL);
1679 	if (!map)
1680 		return -ENOMEM;
1681 
1682 	map->src_dev = dev;
1683 	map->src_supply = id;
1684 	map->alias_dev = alias_dev;
1685 	map->alias_supply = alias_id;
1686 
1687 	list_add(&map->list, &regulator_supply_alias_list);
1688 
1689 	pr_info("Adding alias for supply %s,%s -> %s,%s\n",
1690 		id, dev_name(dev), alias_id, dev_name(alias_dev));
1691 
1692 	return 0;
1693 }
1694 EXPORT_SYMBOL_GPL(regulator_register_supply_alias);
1695 
1696 /**
1697  * regulator_unregister_supply_alias - Remove device alias
1698  *
1699  * @dev: device that will be given as the regulator "consumer"
1700  * @id: Supply name or regulator ID
1701  *
1702  * Remove a lookup alias if one exists for id on dev.
1703  */
1704 void regulator_unregister_supply_alias(struct device *dev, const char *id)
1705 {
1706 	struct regulator_supply_alias *map;
1707 
1708 	map = regulator_find_supply_alias(dev, id);
1709 	if (map) {
1710 		list_del(&map->list);
1711 		kfree(map);
1712 	}
1713 }
1714 EXPORT_SYMBOL_GPL(regulator_unregister_supply_alias);
1715 
1716 /**
1717  * regulator_bulk_register_supply_alias - register multiple aliases
1718  *
1719  * @dev: device that will be given as the regulator "consumer"
1720  * @id: List of supply names or regulator IDs
1721  * @alias_dev: device that should be used to lookup the supply
1722  * @alias_id: List of supply names or regulator IDs that should be used to
1723  * lookup the supply
1724  * @num_id: Number of aliases to register
1725  *
1726  * @return 0 on success, an errno on failure.
1727  *
1728  * This helper function allows drivers to register several supply
1729  * aliases in one operation.  If any of the aliases cannot be
1730  * registered any aliases that were registered will be removed
1731  * before returning to the caller.
1732  */
1733 int regulator_bulk_register_supply_alias(struct device *dev,
1734 					 const char *const *id,
1735 					 struct device *alias_dev,
1736 					 const char *const *alias_id,
1737 					 int num_id)
1738 {
1739 	int i;
1740 	int ret;
1741 
1742 	for (i = 0; i < num_id; ++i) {
1743 		ret = regulator_register_supply_alias(dev, id[i], alias_dev,
1744 						      alias_id[i]);
1745 		if (ret < 0)
1746 			goto err;
1747 	}
1748 
1749 	return 0;
1750 
1751 err:
1752 	dev_err(dev,
1753 		"Failed to create supply alias %s,%s -> %s,%s\n",
1754 		id[i], dev_name(dev), alias_id[i], dev_name(alias_dev));
1755 
1756 	while (--i >= 0)
1757 		regulator_unregister_supply_alias(dev, id[i]);
1758 
1759 	return ret;
1760 }
1761 EXPORT_SYMBOL_GPL(regulator_bulk_register_supply_alias);
1762 
1763 /**
1764  * regulator_bulk_unregister_supply_alias - unregister multiple aliases
1765  *
1766  * @dev: device that will be given as the regulator "consumer"
1767  * @id: List of supply names or regulator IDs
1768  * @num_id: Number of aliases to unregister
1769  *
1770  * This helper function allows drivers to unregister several supply
1771  * aliases in one operation.
1772  */
1773 void regulator_bulk_unregister_supply_alias(struct device *dev,
1774 					    const char *const *id,
1775 					    int num_id)
1776 {
1777 	int i;
1778 
1779 	for (i = 0; i < num_id; ++i)
1780 		regulator_unregister_supply_alias(dev, id[i]);
1781 }
1782 EXPORT_SYMBOL_GPL(regulator_bulk_unregister_supply_alias);
1783 
1784 
1785 /* Manage enable GPIO list. Same GPIO pin can be shared among regulators */
1786 static int regulator_ena_gpio_request(struct regulator_dev *rdev,
1787 				const struct regulator_config *config)
1788 {
1789 	struct regulator_enable_gpio *pin;
1790 	struct gpio_desc *gpiod;
1791 	int ret;
1792 
1793 	gpiod = gpio_to_desc(config->ena_gpio);
1794 
1795 	list_for_each_entry(pin, &regulator_ena_gpio_list, list) {
1796 		if (pin->gpiod == gpiod) {
1797 			rdev_dbg(rdev, "GPIO %d is already used\n",
1798 				config->ena_gpio);
1799 			goto update_ena_gpio_to_rdev;
1800 		}
1801 	}
1802 
1803 	ret = gpio_request_one(config->ena_gpio,
1804 				GPIOF_DIR_OUT | config->ena_gpio_flags,
1805 				rdev_get_name(rdev));
1806 	if (ret)
1807 		return ret;
1808 
1809 	pin = kzalloc(sizeof(struct regulator_enable_gpio), GFP_KERNEL);
1810 	if (pin == NULL) {
1811 		gpio_free(config->ena_gpio);
1812 		return -ENOMEM;
1813 	}
1814 
1815 	pin->gpiod = gpiod;
1816 	pin->ena_gpio_invert = config->ena_gpio_invert;
1817 	list_add(&pin->list, &regulator_ena_gpio_list);
1818 
1819 update_ena_gpio_to_rdev:
1820 	pin->request_count++;
1821 	rdev->ena_pin = pin;
1822 	return 0;
1823 }
1824 
1825 static void regulator_ena_gpio_free(struct regulator_dev *rdev)
1826 {
1827 	struct regulator_enable_gpio *pin, *n;
1828 
1829 	if (!rdev->ena_pin)
1830 		return;
1831 
1832 	/* Free the GPIO only in case of no use */
1833 	list_for_each_entry_safe(pin, n, &regulator_ena_gpio_list, list) {
1834 		if (pin->gpiod == rdev->ena_pin->gpiod) {
1835 			if (pin->request_count <= 1) {
1836 				pin->request_count = 0;
1837 				gpiod_put(pin->gpiod);
1838 				list_del(&pin->list);
1839 				kfree(pin);
1840 				rdev->ena_pin = NULL;
1841 				return;
1842 			} else {
1843 				pin->request_count--;
1844 			}
1845 		}
1846 	}
1847 }
1848 
1849 /**
1850  * regulator_ena_gpio_ctrl - balance enable_count of each GPIO and actual GPIO pin control
1851  * @rdev: regulator_dev structure
1852  * @enable: enable GPIO at initial use?
1853  *
1854  * GPIO is enabled in case of initial use. (enable_count is 0)
1855  * GPIO is disabled when it is not shared any more. (enable_count <= 1)
1856  */
1857 static int regulator_ena_gpio_ctrl(struct regulator_dev *rdev, bool enable)
1858 {
1859 	struct regulator_enable_gpio *pin = rdev->ena_pin;
1860 
1861 	if (!pin)
1862 		return -EINVAL;
1863 
1864 	if (enable) {
1865 		/* Enable GPIO at initial use */
1866 		if (pin->enable_count == 0)
1867 			gpiod_set_value_cansleep(pin->gpiod,
1868 						 !pin->ena_gpio_invert);
1869 
1870 		pin->enable_count++;
1871 	} else {
1872 		if (pin->enable_count > 1) {
1873 			pin->enable_count--;
1874 			return 0;
1875 		}
1876 
1877 		/* Disable GPIO if not used */
1878 		if (pin->enable_count <= 1) {
1879 			gpiod_set_value_cansleep(pin->gpiod,
1880 						 pin->ena_gpio_invert);
1881 			pin->enable_count = 0;
1882 		}
1883 	}
1884 
1885 	return 0;
1886 }
1887 
1888 /**
1889  * _regulator_enable_delay - a delay helper function
1890  * @delay: time to delay in microseconds
1891  *
1892  * Delay for the requested amount of time as per the guidelines in:
1893  *
1894  *     Documentation/timers/timers-howto.txt
1895  *
1896  * The assumption here is that regulators will never be enabled in
1897  * atomic context and therefore sleeping functions can be used.
1898  */
1899 static void _regulator_enable_delay(unsigned int delay)
1900 {
1901 	unsigned int ms = delay / 1000;
1902 	unsigned int us = delay % 1000;
1903 
1904 	if (ms > 0) {
1905 		/*
1906 		 * For small enough values, handle super-millisecond
1907 		 * delays in the usleep_range() call below.
1908 		 */
1909 		if (ms < 20)
1910 			us += ms * 1000;
1911 		else
1912 			msleep(ms);
1913 	}
1914 
1915 	/*
1916 	 * Give the scheduler some room to coalesce with any other
1917 	 * wakeup sources. For delays shorter than 10 us, don't even
1918 	 * bother setting up high-resolution timers and just busy-
1919 	 * loop.
1920 	 */
1921 	if (us >= 10)
1922 		usleep_range(us, us + 100);
1923 	else
1924 		udelay(us);
1925 }
1926 
1927 static int _regulator_do_enable(struct regulator_dev *rdev)
1928 {
1929 	int ret, delay;
1930 
1931 	/* Query before enabling in case configuration dependent.  */
1932 	ret = _regulator_get_enable_time(rdev);
1933 	if (ret >= 0) {
1934 		delay = ret;
1935 	} else {
1936 		rdev_warn(rdev, "enable_time() failed: %d\n", ret);
1937 		delay = 0;
1938 	}
1939 
1940 	trace_regulator_enable(rdev_get_name(rdev));
1941 
1942 	if (rdev->desc->off_on_delay) {
1943 		/* if needed, keep a distance of off_on_delay from last time
1944 		 * this regulator was disabled.
1945 		 */
1946 		unsigned long start_jiffy = jiffies;
1947 		unsigned long intended, max_delay, remaining;
1948 
1949 		max_delay = usecs_to_jiffies(rdev->desc->off_on_delay);
1950 		intended = rdev->last_off_jiffy + max_delay;
1951 
1952 		if (time_before(start_jiffy, intended)) {
1953 			/* calc remaining jiffies to deal with one-time
1954 			 * timer wrapping.
1955 			 * in case of multiple timer wrapping, either it can be
1956 			 * detected by out-of-range remaining, or it cannot be
1957 			 * detected and we gets a panelty of
1958 			 * _regulator_enable_delay().
1959 			 */
1960 			remaining = intended - start_jiffy;
1961 			if (remaining <= max_delay)
1962 				_regulator_enable_delay(
1963 						jiffies_to_usecs(remaining));
1964 		}
1965 	}
1966 
1967 	if (rdev->ena_pin) {
1968 		if (!rdev->ena_gpio_state) {
1969 			ret = regulator_ena_gpio_ctrl(rdev, true);
1970 			if (ret < 0)
1971 				return ret;
1972 			rdev->ena_gpio_state = 1;
1973 		}
1974 	} else if (rdev->desc->ops->enable) {
1975 		ret = rdev->desc->ops->enable(rdev);
1976 		if (ret < 0)
1977 			return ret;
1978 	} else {
1979 		return -EINVAL;
1980 	}
1981 
1982 	/* Allow the regulator to ramp; it would be useful to extend
1983 	 * this for bulk operations so that the regulators can ramp
1984 	 * together.  */
1985 	trace_regulator_enable_delay(rdev_get_name(rdev));
1986 
1987 	_regulator_enable_delay(delay);
1988 
1989 	trace_regulator_enable_complete(rdev_get_name(rdev));
1990 
1991 	return 0;
1992 }
1993 
1994 /* locks held by regulator_enable() */
1995 static int _regulator_enable(struct regulator_dev *rdev)
1996 {
1997 	int ret;
1998 
1999 	lockdep_assert_held_once(&rdev->mutex);
2000 
2001 	/* check voltage and requested load before enabling */
2002 	if (rdev->constraints &&
2003 	    (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS))
2004 		drms_uA_update(rdev);
2005 
2006 	if (rdev->use_count == 0) {
2007 		/* The regulator may on if it's not switchable or left on */
2008 		ret = _regulator_is_enabled(rdev);
2009 		if (ret == -EINVAL || ret == 0) {
2010 			if (!_regulator_can_change_status(rdev))
2011 				return -EPERM;
2012 
2013 			ret = _regulator_do_enable(rdev);
2014 			if (ret < 0)
2015 				return ret;
2016 
2017 		} else if (ret < 0) {
2018 			rdev_err(rdev, "is_enabled() failed: %d\n", ret);
2019 			return ret;
2020 		}
2021 		/* Fallthrough on positive return values - already enabled */
2022 	}
2023 
2024 	rdev->use_count++;
2025 
2026 	return 0;
2027 }
2028 
2029 /**
2030  * regulator_enable - enable regulator output
2031  * @regulator: regulator source
2032  *
2033  * Request that the regulator be enabled with the regulator output at
2034  * the predefined voltage or current value.  Calls to regulator_enable()
2035  * must be balanced with calls to regulator_disable().
2036  *
2037  * NOTE: the output value can be set by other drivers, boot loader or may be
2038  * hardwired in the regulator.
2039  */
2040 int regulator_enable(struct regulator *regulator)
2041 {
2042 	struct regulator_dev *rdev = regulator->rdev;
2043 	int ret = 0;
2044 
2045 	if (regulator->always_on)
2046 		return 0;
2047 
2048 	if (rdev->supply) {
2049 		ret = regulator_enable(rdev->supply);
2050 		if (ret != 0)
2051 			return ret;
2052 	}
2053 
2054 	mutex_lock(&rdev->mutex);
2055 	ret = _regulator_enable(rdev);
2056 	mutex_unlock(&rdev->mutex);
2057 
2058 	if (ret != 0 && rdev->supply)
2059 		regulator_disable(rdev->supply);
2060 
2061 	return ret;
2062 }
2063 EXPORT_SYMBOL_GPL(regulator_enable);
2064 
2065 static int _regulator_do_disable(struct regulator_dev *rdev)
2066 {
2067 	int ret;
2068 
2069 	trace_regulator_disable(rdev_get_name(rdev));
2070 
2071 	if (rdev->ena_pin) {
2072 		if (rdev->ena_gpio_state) {
2073 			ret = regulator_ena_gpio_ctrl(rdev, false);
2074 			if (ret < 0)
2075 				return ret;
2076 			rdev->ena_gpio_state = 0;
2077 		}
2078 
2079 	} else if (rdev->desc->ops->disable) {
2080 		ret = rdev->desc->ops->disable(rdev);
2081 		if (ret != 0)
2082 			return ret;
2083 	}
2084 
2085 	/* cares about last_off_jiffy only if off_on_delay is required by
2086 	 * device.
2087 	 */
2088 	if (rdev->desc->off_on_delay)
2089 		rdev->last_off_jiffy = jiffies;
2090 
2091 	trace_regulator_disable_complete(rdev_get_name(rdev));
2092 
2093 	return 0;
2094 }
2095 
2096 /* locks held by regulator_disable() */
2097 static int _regulator_disable(struct regulator_dev *rdev)
2098 {
2099 	int ret = 0;
2100 
2101 	lockdep_assert_held_once(&rdev->mutex);
2102 
2103 	if (WARN(rdev->use_count <= 0,
2104 		 "unbalanced disables for %s\n", rdev_get_name(rdev)))
2105 		return -EIO;
2106 
2107 	/* are we the last user and permitted to disable ? */
2108 	if (rdev->use_count == 1 &&
2109 	    (rdev->constraints && !rdev->constraints->always_on)) {
2110 
2111 		/* we are last user */
2112 		if (_regulator_can_change_status(rdev)) {
2113 			ret = _notifier_call_chain(rdev,
2114 						   REGULATOR_EVENT_PRE_DISABLE,
2115 						   NULL);
2116 			if (ret & NOTIFY_STOP_MASK)
2117 				return -EINVAL;
2118 
2119 			ret = _regulator_do_disable(rdev);
2120 			if (ret < 0) {
2121 				rdev_err(rdev, "failed to disable\n");
2122 				_notifier_call_chain(rdev,
2123 						REGULATOR_EVENT_ABORT_DISABLE,
2124 						NULL);
2125 				return ret;
2126 			}
2127 			_notifier_call_chain(rdev, REGULATOR_EVENT_DISABLE,
2128 					NULL);
2129 		}
2130 
2131 		rdev->use_count = 0;
2132 	} else if (rdev->use_count > 1) {
2133 
2134 		if (rdev->constraints &&
2135 			(rdev->constraints->valid_ops_mask &
2136 			REGULATOR_CHANGE_DRMS))
2137 			drms_uA_update(rdev);
2138 
2139 		rdev->use_count--;
2140 	}
2141 
2142 	return ret;
2143 }
2144 
2145 /**
2146  * regulator_disable - disable regulator output
2147  * @regulator: regulator source
2148  *
2149  * Disable the regulator output voltage or current.  Calls to
2150  * regulator_enable() must be balanced with calls to
2151  * regulator_disable().
2152  *
2153  * NOTE: this will only disable the regulator output if no other consumer
2154  * devices have it enabled, the regulator device supports disabling and
2155  * machine constraints permit this operation.
2156  */
2157 int regulator_disable(struct regulator *regulator)
2158 {
2159 	struct regulator_dev *rdev = regulator->rdev;
2160 	int ret = 0;
2161 
2162 	if (regulator->always_on)
2163 		return 0;
2164 
2165 	mutex_lock(&rdev->mutex);
2166 	ret = _regulator_disable(rdev);
2167 	mutex_unlock(&rdev->mutex);
2168 
2169 	if (ret == 0 && rdev->supply)
2170 		regulator_disable(rdev->supply);
2171 
2172 	return ret;
2173 }
2174 EXPORT_SYMBOL_GPL(regulator_disable);
2175 
2176 /* locks held by regulator_force_disable() */
2177 static int _regulator_force_disable(struct regulator_dev *rdev)
2178 {
2179 	int ret = 0;
2180 
2181 	lockdep_assert_held_once(&rdev->mutex);
2182 
2183 	ret = _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
2184 			REGULATOR_EVENT_PRE_DISABLE, NULL);
2185 	if (ret & NOTIFY_STOP_MASK)
2186 		return -EINVAL;
2187 
2188 	ret = _regulator_do_disable(rdev);
2189 	if (ret < 0) {
2190 		rdev_err(rdev, "failed to force disable\n");
2191 		_notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
2192 				REGULATOR_EVENT_ABORT_DISABLE, NULL);
2193 		return ret;
2194 	}
2195 
2196 	_notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
2197 			REGULATOR_EVENT_DISABLE, NULL);
2198 
2199 	return 0;
2200 }
2201 
2202 /**
2203  * regulator_force_disable - force disable regulator output
2204  * @regulator: regulator source
2205  *
2206  * Forcibly disable the regulator output voltage or current.
2207  * NOTE: this *will* disable the regulator output even if other consumer
2208  * devices have it enabled. This should be used for situations when device
2209  * damage will likely occur if the regulator is not disabled (e.g. over temp).
2210  */
2211 int regulator_force_disable(struct regulator *regulator)
2212 {
2213 	struct regulator_dev *rdev = regulator->rdev;
2214 	int ret;
2215 
2216 	mutex_lock(&rdev->mutex);
2217 	regulator->uA_load = 0;
2218 	ret = _regulator_force_disable(regulator->rdev);
2219 	mutex_unlock(&rdev->mutex);
2220 
2221 	if (rdev->supply)
2222 		while (rdev->open_count--)
2223 			regulator_disable(rdev->supply);
2224 
2225 	return ret;
2226 }
2227 EXPORT_SYMBOL_GPL(regulator_force_disable);
2228 
2229 static void regulator_disable_work(struct work_struct *work)
2230 {
2231 	struct regulator_dev *rdev = container_of(work, struct regulator_dev,
2232 						  disable_work.work);
2233 	int count, i, ret;
2234 
2235 	mutex_lock(&rdev->mutex);
2236 
2237 	BUG_ON(!rdev->deferred_disables);
2238 
2239 	count = rdev->deferred_disables;
2240 	rdev->deferred_disables = 0;
2241 
2242 	for (i = 0; i < count; i++) {
2243 		ret = _regulator_disable(rdev);
2244 		if (ret != 0)
2245 			rdev_err(rdev, "Deferred disable failed: %d\n", ret);
2246 	}
2247 
2248 	mutex_unlock(&rdev->mutex);
2249 
2250 	if (rdev->supply) {
2251 		for (i = 0; i < count; i++) {
2252 			ret = regulator_disable(rdev->supply);
2253 			if (ret != 0) {
2254 				rdev_err(rdev,
2255 					 "Supply disable failed: %d\n", ret);
2256 			}
2257 		}
2258 	}
2259 }
2260 
2261 /**
2262  * regulator_disable_deferred - disable regulator output with delay
2263  * @regulator: regulator source
2264  * @ms: miliseconds until the regulator is disabled
2265  *
2266  * Execute regulator_disable() on the regulator after a delay.  This
2267  * is intended for use with devices that require some time to quiesce.
2268  *
2269  * NOTE: this will only disable the regulator output if no other consumer
2270  * devices have it enabled, the regulator device supports disabling and
2271  * machine constraints permit this operation.
2272  */
2273 int regulator_disable_deferred(struct regulator *regulator, int ms)
2274 {
2275 	struct regulator_dev *rdev = regulator->rdev;
2276 	int ret;
2277 
2278 	if (regulator->always_on)
2279 		return 0;
2280 
2281 	if (!ms)
2282 		return regulator_disable(regulator);
2283 
2284 	mutex_lock(&rdev->mutex);
2285 	rdev->deferred_disables++;
2286 	mutex_unlock(&rdev->mutex);
2287 
2288 	ret = queue_delayed_work(system_power_efficient_wq,
2289 				 &rdev->disable_work,
2290 				 msecs_to_jiffies(ms));
2291 	if (ret < 0)
2292 		return ret;
2293 	else
2294 		return 0;
2295 }
2296 EXPORT_SYMBOL_GPL(regulator_disable_deferred);
2297 
2298 static int _regulator_is_enabled(struct regulator_dev *rdev)
2299 {
2300 	/* A GPIO control always takes precedence */
2301 	if (rdev->ena_pin)
2302 		return rdev->ena_gpio_state;
2303 
2304 	/* If we don't know then assume that the regulator is always on */
2305 	if (!rdev->desc->ops->is_enabled)
2306 		return 1;
2307 
2308 	return rdev->desc->ops->is_enabled(rdev);
2309 }
2310 
2311 /**
2312  * regulator_is_enabled - is the regulator output enabled
2313  * @regulator: regulator source
2314  *
2315  * Returns positive if the regulator driver backing the source/client
2316  * has requested that the device be enabled, zero if it hasn't, else a
2317  * negative errno code.
2318  *
2319  * Note that the device backing this regulator handle can have multiple
2320  * users, so it might be enabled even if regulator_enable() was never
2321  * called for this particular source.
2322  */
2323 int regulator_is_enabled(struct regulator *regulator)
2324 {
2325 	int ret;
2326 
2327 	if (regulator->always_on)
2328 		return 1;
2329 
2330 	mutex_lock(&regulator->rdev->mutex);
2331 	ret = _regulator_is_enabled(regulator->rdev);
2332 	mutex_unlock(&regulator->rdev->mutex);
2333 
2334 	return ret;
2335 }
2336 EXPORT_SYMBOL_GPL(regulator_is_enabled);
2337 
2338 /**
2339  * regulator_can_change_voltage - check if regulator can change voltage
2340  * @regulator: regulator source
2341  *
2342  * Returns positive if the regulator driver backing the source/client
2343  * can change its voltage, false otherwise. Useful for detecting fixed
2344  * or dummy regulators and disabling voltage change logic in the client
2345  * driver.
2346  */
2347 int regulator_can_change_voltage(struct regulator *regulator)
2348 {
2349 	struct regulator_dev	*rdev = regulator->rdev;
2350 
2351 	if (rdev->constraints &&
2352 	    (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
2353 		if (rdev->desc->n_voltages - rdev->desc->linear_min_sel > 1)
2354 			return 1;
2355 
2356 		if (rdev->desc->continuous_voltage_range &&
2357 		    rdev->constraints->min_uV && rdev->constraints->max_uV &&
2358 		    rdev->constraints->min_uV != rdev->constraints->max_uV)
2359 			return 1;
2360 	}
2361 
2362 	return 0;
2363 }
2364 EXPORT_SYMBOL_GPL(regulator_can_change_voltage);
2365 
2366 /**
2367  * regulator_count_voltages - count regulator_list_voltage() selectors
2368  * @regulator: regulator source
2369  *
2370  * Returns number of selectors, or negative errno.  Selectors are
2371  * numbered starting at zero, and typically correspond to bitfields
2372  * in hardware registers.
2373  */
2374 int regulator_count_voltages(struct regulator *regulator)
2375 {
2376 	struct regulator_dev	*rdev = regulator->rdev;
2377 
2378 	if (rdev->desc->n_voltages)
2379 		return rdev->desc->n_voltages;
2380 
2381 	if (!rdev->supply)
2382 		return -EINVAL;
2383 
2384 	return regulator_count_voltages(rdev->supply);
2385 }
2386 EXPORT_SYMBOL_GPL(regulator_count_voltages);
2387 
2388 /**
2389  * regulator_list_voltage - enumerate supported voltages
2390  * @regulator: regulator source
2391  * @selector: identify voltage to list
2392  * Context: can sleep
2393  *
2394  * Returns a voltage that can be passed to @regulator_set_voltage(),
2395  * zero if this selector code can't be used on this system, or a
2396  * negative errno.
2397  */
2398 int regulator_list_voltage(struct regulator *regulator, unsigned selector)
2399 {
2400 	struct regulator_dev *rdev = regulator->rdev;
2401 	const struct regulator_ops *ops = rdev->desc->ops;
2402 	int ret;
2403 
2404 	if (rdev->desc->fixed_uV && rdev->desc->n_voltages == 1 && !selector)
2405 		return rdev->desc->fixed_uV;
2406 
2407 	if (ops->list_voltage) {
2408 		if (selector >= rdev->desc->n_voltages)
2409 			return -EINVAL;
2410 		mutex_lock(&rdev->mutex);
2411 		ret = ops->list_voltage(rdev, selector);
2412 		mutex_unlock(&rdev->mutex);
2413 	} else if (rdev->supply) {
2414 		ret = regulator_list_voltage(rdev->supply, selector);
2415 	} else {
2416 		return -EINVAL;
2417 	}
2418 
2419 	if (ret > 0) {
2420 		if (ret < rdev->constraints->min_uV)
2421 			ret = 0;
2422 		else if (ret > rdev->constraints->max_uV)
2423 			ret = 0;
2424 	}
2425 
2426 	return ret;
2427 }
2428 EXPORT_SYMBOL_GPL(regulator_list_voltage);
2429 
2430 /**
2431  * regulator_get_regmap - get the regulator's register map
2432  * @regulator: regulator source
2433  *
2434  * Returns the register map for the given regulator, or an ERR_PTR value
2435  * if the regulator doesn't use regmap.
2436  */
2437 struct regmap *regulator_get_regmap(struct regulator *regulator)
2438 {
2439 	struct regmap *map = regulator->rdev->regmap;
2440 
2441 	return map ? map : ERR_PTR(-EOPNOTSUPP);
2442 }
2443 
2444 /**
2445  * regulator_get_hardware_vsel_register - get the HW voltage selector register
2446  * @regulator: regulator source
2447  * @vsel_reg: voltage selector register, output parameter
2448  * @vsel_mask: mask for voltage selector bitfield, output parameter
2449  *
2450  * Returns the hardware register offset and bitmask used for setting the
2451  * regulator voltage. This might be useful when configuring voltage-scaling
2452  * hardware or firmware that can make I2C requests behind the kernel's back,
2453  * for example.
2454  *
2455  * On success, the output parameters @vsel_reg and @vsel_mask are filled in
2456  * and 0 is returned, otherwise a negative errno is returned.
2457  */
2458 int regulator_get_hardware_vsel_register(struct regulator *regulator,
2459 					 unsigned *vsel_reg,
2460 					 unsigned *vsel_mask)
2461 {
2462 	struct regulator_dev *rdev = regulator->rdev;
2463 	const struct regulator_ops *ops = rdev->desc->ops;
2464 
2465 	if (ops->set_voltage_sel != regulator_set_voltage_sel_regmap)
2466 		return -EOPNOTSUPP;
2467 
2468 	 *vsel_reg = rdev->desc->vsel_reg;
2469 	 *vsel_mask = rdev->desc->vsel_mask;
2470 
2471 	 return 0;
2472 }
2473 EXPORT_SYMBOL_GPL(regulator_get_hardware_vsel_register);
2474 
2475 /**
2476  * regulator_list_hardware_vsel - get the HW-specific register value for a selector
2477  * @regulator: regulator source
2478  * @selector: identify voltage to list
2479  *
2480  * Converts the selector to a hardware-specific voltage selector that can be
2481  * directly written to the regulator registers. The address of the voltage
2482  * register can be determined by calling @regulator_get_hardware_vsel_register.
2483  *
2484  * On error a negative errno is returned.
2485  */
2486 int regulator_list_hardware_vsel(struct regulator *regulator,
2487 				 unsigned selector)
2488 {
2489 	struct regulator_dev *rdev = regulator->rdev;
2490 	const struct regulator_ops *ops = rdev->desc->ops;
2491 
2492 	if (selector >= rdev->desc->n_voltages)
2493 		return -EINVAL;
2494 	if (ops->set_voltage_sel != regulator_set_voltage_sel_regmap)
2495 		return -EOPNOTSUPP;
2496 
2497 	return selector;
2498 }
2499 EXPORT_SYMBOL_GPL(regulator_list_hardware_vsel);
2500 
2501 /**
2502  * regulator_get_linear_step - return the voltage step size between VSEL values
2503  * @regulator: regulator source
2504  *
2505  * Returns the voltage step size between VSEL values for linear
2506  * regulators, or return 0 if the regulator isn't a linear regulator.
2507  */
2508 unsigned int regulator_get_linear_step(struct regulator *regulator)
2509 {
2510 	struct regulator_dev *rdev = regulator->rdev;
2511 
2512 	return rdev->desc->uV_step;
2513 }
2514 EXPORT_SYMBOL_GPL(regulator_get_linear_step);
2515 
2516 /**
2517  * regulator_is_supported_voltage - check if a voltage range can be supported
2518  *
2519  * @regulator: Regulator to check.
2520  * @min_uV: Minimum required voltage in uV.
2521  * @max_uV: Maximum required voltage in uV.
2522  *
2523  * Returns a boolean or a negative error code.
2524  */
2525 int regulator_is_supported_voltage(struct regulator *regulator,
2526 				   int min_uV, int max_uV)
2527 {
2528 	struct regulator_dev *rdev = regulator->rdev;
2529 	int i, voltages, ret;
2530 
2531 	/* If we can't change voltage check the current voltage */
2532 	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
2533 		ret = regulator_get_voltage(regulator);
2534 		if (ret >= 0)
2535 			return min_uV <= ret && ret <= max_uV;
2536 		else
2537 			return ret;
2538 	}
2539 
2540 	/* Any voltage within constrains range is fine? */
2541 	if (rdev->desc->continuous_voltage_range)
2542 		return min_uV >= rdev->constraints->min_uV &&
2543 				max_uV <= rdev->constraints->max_uV;
2544 
2545 	ret = regulator_count_voltages(regulator);
2546 	if (ret < 0)
2547 		return ret;
2548 	voltages = ret;
2549 
2550 	for (i = 0; i < voltages; i++) {
2551 		ret = regulator_list_voltage(regulator, i);
2552 
2553 		if (ret >= min_uV && ret <= max_uV)
2554 			return 1;
2555 	}
2556 
2557 	return 0;
2558 }
2559 EXPORT_SYMBOL_GPL(regulator_is_supported_voltage);
2560 
2561 static int _regulator_call_set_voltage(struct regulator_dev *rdev,
2562 				       int min_uV, int max_uV,
2563 				       unsigned *selector)
2564 {
2565 	struct pre_voltage_change_data data;
2566 	int ret;
2567 
2568 	data.old_uV = _regulator_get_voltage(rdev);
2569 	data.min_uV = min_uV;
2570 	data.max_uV = max_uV;
2571 	ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE,
2572 				   &data);
2573 	if (ret & NOTIFY_STOP_MASK)
2574 		return -EINVAL;
2575 
2576 	ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV, selector);
2577 	if (ret >= 0)
2578 		return ret;
2579 
2580 	_notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE,
2581 			     (void *)data.old_uV);
2582 
2583 	return ret;
2584 }
2585 
2586 static int _regulator_call_set_voltage_sel(struct regulator_dev *rdev,
2587 					   int uV, unsigned selector)
2588 {
2589 	struct pre_voltage_change_data data;
2590 	int ret;
2591 
2592 	data.old_uV = _regulator_get_voltage(rdev);
2593 	data.min_uV = uV;
2594 	data.max_uV = uV;
2595 	ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE,
2596 				   &data);
2597 	if (ret & NOTIFY_STOP_MASK)
2598 		return -EINVAL;
2599 
2600 	ret = rdev->desc->ops->set_voltage_sel(rdev, selector);
2601 	if (ret >= 0)
2602 		return ret;
2603 
2604 	_notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE,
2605 			     (void *)data.old_uV);
2606 
2607 	return ret;
2608 }
2609 
2610 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
2611 				     int min_uV, int max_uV)
2612 {
2613 	int ret;
2614 	int delay = 0;
2615 	int best_val = 0;
2616 	unsigned int selector;
2617 	int old_selector = -1;
2618 
2619 	trace_regulator_set_voltage(rdev_get_name(rdev), min_uV, max_uV);
2620 
2621 	min_uV += rdev->constraints->uV_offset;
2622 	max_uV += rdev->constraints->uV_offset;
2623 
2624 	/*
2625 	 * If we can't obtain the old selector there is not enough
2626 	 * info to call set_voltage_time_sel().
2627 	 */
2628 	if (_regulator_is_enabled(rdev) &&
2629 	    rdev->desc->ops->set_voltage_time_sel &&
2630 	    rdev->desc->ops->get_voltage_sel) {
2631 		old_selector = rdev->desc->ops->get_voltage_sel(rdev);
2632 		if (old_selector < 0)
2633 			return old_selector;
2634 	}
2635 
2636 	if (rdev->desc->ops->set_voltage) {
2637 		ret = _regulator_call_set_voltage(rdev, min_uV, max_uV,
2638 						  &selector);
2639 
2640 		if (ret >= 0) {
2641 			if (rdev->desc->ops->list_voltage)
2642 				best_val = rdev->desc->ops->list_voltage(rdev,
2643 									 selector);
2644 			else
2645 				best_val = _regulator_get_voltage(rdev);
2646 		}
2647 
2648 	} else if (rdev->desc->ops->set_voltage_sel) {
2649 		if (rdev->desc->ops->map_voltage) {
2650 			ret = rdev->desc->ops->map_voltage(rdev, min_uV,
2651 							   max_uV);
2652 		} else {
2653 			if (rdev->desc->ops->list_voltage ==
2654 			    regulator_list_voltage_linear)
2655 				ret = regulator_map_voltage_linear(rdev,
2656 								min_uV, max_uV);
2657 			else if (rdev->desc->ops->list_voltage ==
2658 				 regulator_list_voltage_linear_range)
2659 				ret = regulator_map_voltage_linear_range(rdev,
2660 								min_uV, max_uV);
2661 			else
2662 				ret = regulator_map_voltage_iterate(rdev,
2663 								min_uV, max_uV);
2664 		}
2665 
2666 		if (ret >= 0) {
2667 			best_val = rdev->desc->ops->list_voltage(rdev, ret);
2668 			if (min_uV <= best_val && max_uV >= best_val) {
2669 				selector = ret;
2670 				if (old_selector == selector)
2671 					ret = 0;
2672 				else
2673 					ret = _regulator_call_set_voltage_sel(
2674 						rdev, best_val, selector);
2675 			} else {
2676 				ret = -EINVAL;
2677 			}
2678 		}
2679 	} else {
2680 		ret = -EINVAL;
2681 	}
2682 
2683 	/* Call set_voltage_time_sel if successfully obtained old_selector */
2684 	if (ret == 0 && !rdev->constraints->ramp_disable && old_selector >= 0
2685 		&& old_selector != selector) {
2686 
2687 		delay = rdev->desc->ops->set_voltage_time_sel(rdev,
2688 						old_selector, selector);
2689 		if (delay < 0) {
2690 			rdev_warn(rdev, "set_voltage_time_sel() failed: %d\n",
2691 				  delay);
2692 			delay = 0;
2693 		}
2694 
2695 		/* Insert any necessary delays */
2696 		if (delay >= 1000) {
2697 			mdelay(delay / 1000);
2698 			udelay(delay % 1000);
2699 		} else if (delay) {
2700 			udelay(delay);
2701 		}
2702 	}
2703 
2704 	if (ret == 0 && best_val >= 0) {
2705 		unsigned long data = best_val;
2706 
2707 		_notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE,
2708 				     (void *)data);
2709 	}
2710 
2711 	trace_regulator_set_voltage_complete(rdev_get_name(rdev), best_val);
2712 
2713 	return ret;
2714 }
2715 
2716 /**
2717  * regulator_set_voltage - set regulator output voltage
2718  * @regulator: regulator source
2719  * @min_uV: Minimum required voltage in uV
2720  * @max_uV: Maximum acceptable voltage in uV
2721  *
2722  * Sets a voltage regulator to the desired output voltage. This can be set
2723  * during any regulator state. IOW, regulator can be disabled or enabled.
2724  *
2725  * If the regulator is enabled then the voltage will change to the new value
2726  * immediately otherwise if the regulator is disabled the regulator will
2727  * output at the new voltage when enabled.
2728  *
2729  * NOTE: If the regulator is shared between several devices then the lowest
2730  * request voltage that meets the system constraints will be used.
2731  * Regulator system constraints must be set for this regulator before
2732  * calling this function otherwise this call will fail.
2733  */
2734 int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
2735 {
2736 	struct regulator_dev *rdev = regulator->rdev;
2737 	int ret = 0;
2738 	int old_min_uV, old_max_uV;
2739 	int current_uV;
2740 
2741 	mutex_lock(&rdev->mutex);
2742 
2743 	/* If we're setting the same range as last time the change
2744 	 * should be a noop (some cpufreq implementations use the same
2745 	 * voltage for multiple frequencies, for example).
2746 	 */
2747 	if (regulator->min_uV == min_uV && regulator->max_uV == max_uV)
2748 		goto out;
2749 
2750 	/* If we're trying to set a range that overlaps the current voltage,
2751 	 * return successfully even though the regulator does not support
2752 	 * changing the voltage.
2753 	 */
2754 	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
2755 		current_uV = _regulator_get_voltage(rdev);
2756 		if (min_uV <= current_uV && current_uV <= max_uV) {
2757 			regulator->min_uV = min_uV;
2758 			regulator->max_uV = max_uV;
2759 			goto out;
2760 		}
2761 	}
2762 
2763 	/* sanity check */
2764 	if (!rdev->desc->ops->set_voltage &&
2765 	    !rdev->desc->ops->set_voltage_sel) {
2766 		ret = -EINVAL;
2767 		goto out;
2768 	}
2769 
2770 	/* constraints check */
2771 	ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
2772 	if (ret < 0)
2773 		goto out;
2774 
2775 	/* restore original values in case of error */
2776 	old_min_uV = regulator->min_uV;
2777 	old_max_uV = regulator->max_uV;
2778 	regulator->min_uV = min_uV;
2779 	regulator->max_uV = max_uV;
2780 
2781 	ret = regulator_check_consumers(rdev, &min_uV, &max_uV);
2782 	if (ret < 0)
2783 		goto out2;
2784 
2785 	ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
2786 	if (ret < 0)
2787 		goto out2;
2788 
2789 out:
2790 	mutex_unlock(&rdev->mutex);
2791 	return ret;
2792 out2:
2793 	regulator->min_uV = old_min_uV;
2794 	regulator->max_uV = old_max_uV;
2795 	mutex_unlock(&rdev->mutex);
2796 	return ret;
2797 }
2798 EXPORT_SYMBOL_GPL(regulator_set_voltage);
2799 
2800 /**
2801  * regulator_set_voltage_time - get raise/fall time
2802  * @regulator: regulator source
2803  * @old_uV: starting voltage in microvolts
2804  * @new_uV: target voltage in microvolts
2805  *
2806  * Provided with the starting and ending voltage, this function attempts to
2807  * calculate the time in microseconds required to rise or fall to this new
2808  * voltage.
2809  */
2810 int regulator_set_voltage_time(struct regulator *regulator,
2811 			       int old_uV, int new_uV)
2812 {
2813 	struct regulator_dev *rdev = regulator->rdev;
2814 	const struct regulator_ops *ops = rdev->desc->ops;
2815 	int old_sel = -1;
2816 	int new_sel = -1;
2817 	int voltage;
2818 	int i;
2819 
2820 	/* Currently requires operations to do this */
2821 	if (!ops->list_voltage || !ops->set_voltage_time_sel
2822 	    || !rdev->desc->n_voltages)
2823 		return -EINVAL;
2824 
2825 	for (i = 0; i < rdev->desc->n_voltages; i++) {
2826 		/* We only look for exact voltage matches here */
2827 		voltage = regulator_list_voltage(regulator, i);
2828 		if (voltage < 0)
2829 			return -EINVAL;
2830 		if (voltage == 0)
2831 			continue;
2832 		if (voltage == old_uV)
2833 			old_sel = i;
2834 		if (voltage == new_uV)
2835 			new_sel = i;
2836 	}
2837 
2838 	if (old_sel < 0 || new_sel < 0)
2839 		return -EINVAL;
2840 
2841 	return ops->set_voltage_time_sel(rdev, old_sel, new_sel);
2842 }
2843 EXPORT_SYMBOL_GPL(regulator_set_voltage_time);
2844 
2845 /**
2846  * regulator_set_voltage_time_sel - get raise/fall time
2847  * @rdev: regulator source device
2848  * @old_selector: selector for starting voltage
2849  * @new_selector: selector for target voltage
2850  *
2851  * Provided with the starting and target voltage selectors, this function
2852  * returns time in microseconds required to rise or fall to this new voltage
2853  *
2854  * Drivers providing ramp_delay in regulation_constraints can use this as their
2855  * set_voltage_time_sel() operation.
2856  */
2857 int regulator_set_voltage_time_sel(struct regulator_dev *rdev,
2858 				   unsigned int old_selector,
2859 				   unsigned int new_selector)
2860 {
2861 	unsigned int ramp_delay = 0;
2862 	int old_volt, new_volt;
2863 
2864 	if (rdev->constraints->ramp_delay)
2865 		ramp_delay = rdev->constraints->ramp_delay;
2866 	else if (rdev->desc->ramp_delay)
2867 		ramp_delay = rdev->desc->ramp_delay;
2868 
2869 	if (ramp_delay == 0) {
2870 		rdev_warn(rdev, "ramp_delay not set\n");
2871 		return 0;
2872 	}
2873 
2874 	/* sanity check */
2875 	if (!rdev->desc->ops->list_voltage)
2876 		return -EINVAL;
2877 
2878 	old_volt = rdev->desc->ops->list_voltage(rdev, old_selector);
2879 	new_volt = rdev->desc->ops->list_voltage(rdev, new_selector);
2880 
2881 	return DIV_ROUND_UP(abs(new_volt - old_volt), ramp_delay);
2882 }
2883 EXPORT_SYMBOL_GPL(regulator_set_voltage_time_sel);
2884 
2885 /**
2886  * regulator_sync_voltage - re-apply last regulator output voltage
2887  * @regulator: regulator source
2888  *
2889  * Re-apply the last configured voltage.  This is intended to be used
2890  * where some external control source the consumer is cooperating with
2891  * has caused the configured voltage to change.
2892  */
2893 int regulator_sync_voltage(struct regulator *regulator)
2894 {
2895 	struct regulator_dev *rdev = regulator->rdev;
2896 	int ret, min_uV, max_uV;
2897 
2898 	mutex_lock(&rdev->mutex);
2899 
2900 	if (!rdev->desc->ops->set_voltage &&
2901 	    !rdev->desc->ops->set_voltage_sel) {
2902 		ret = -EINVAL;
2903 		goto out;
2904 	}
2905 
2906 	/* This is only going to work if we've had a voltage configured. */
2907 	if (!regulator->min_uV && !regulator->max_uV) {
2908 		ret = -EINVAL;
2909 		goto out;
2910 	}
2911 
2912 	min_uV = regulator->min_uV;
2913 	max_uV = regulator->max_uV;
2914 
2915 	/* This should be a paranoia check... */
2916 	ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
2917 	if (ret < 0)
2918 		goto out;
2919 
2920 	ret = regulator_check_consumers(rdev, &min_uV, &max_uV);
2921 	if (ret < 0)
2922 		goto out;
2923 
2924 	ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
2925 
2926 out:
2927 	mutex_unlock(&rdev->mutex);
2928 	return ret;
2929 }
2930 EXPORT_SYMBOL_GPL(regulator_sync_voltage);
2931 
2932 static int _regulator_get_voltage(struct regulator_dev *rdev)
2933 {
2934 	int sel, ret;
2935 
2936 	if (rdev->desc->ops->get_voltage_sel) {
2937 		sel = rdev->desc->ops->get_voltage_sel(rdev);
2938 		if (sel < 0)
2939 			return sel;
2940 		ret = rdev->desc->ops->list_voltage(rdev, sel);
2941 	} else if (rdev->desc->ops->get_voltage) {
2942 		ret = rdev->desc->ops->get_voltage(rdev);
2943 	} else if (rdev->desc->ops->list_voltage) {
2944 		ret = rdev->desc->ops->list_voltage(rdev, 0);
2945 	} else if (rdev->desc->fixed_uV && (rdev->desc->n_voltages == 1)) {
2946 		ret = rdev->desc->fixed_uV;
2947 	} else if (rdev->supply) {
2948 		ret = regulator_get_voltage(rdev->supply);
2949 	} else {
2950 		return -EINVAL;
2951 	}
2952 
2953 	if (ret < 0)
2954 		return ret;
2955 	return ret - rdev->constraints->uV_offset;
2956 }
2957 
2958 /**
2959  * regulator_get_voltage - get regulator output voltage
2960  * @regulator: regulator source
2961  *
2962  * This returns the current regulator voltage in uV.
2963  *
2964  * NOTE: If the regulator is disabled it will return the voltage value. This
2965  * function should not be used to determine regulator state.
2966  */
2967 int regulator_get_voltage(struct regulator *regulator)
2968 {
2969 	int ret;
2970 
2971 	mutex_lock(&regulator->rdev->mutex);
2972 
2973 	ret = _regulator_get_voltage(regulator->rdev);
2974 
2975 	mutex_unlock(&regulator->rdev->mutex);
2976 
2977 	return ret;
2978 }
2979 EXPORT_SYMBOL_GPL(regulator_get_voltage);
2980 
2981 /**
2982  * regulator_set_current_limit - set regulator output current limit
2983  * @regulator: regulator source
2984  * @min_uA: Minimum supported current in uA
2985  * @max_uA: Maximum supported current in uA
2986  *
2987  * Sets current sink to the desired output current. This can be set during
2988  * any regulator state. IOW, regulator can be disabled or enabled.
2989  *
2990  * If the regulator is enabled then the current will change to the new value
2991  * immediately otherwise if the regulator is disabled the regulator will
2992  * output at the new current when enabled.
2993  *
2994  * NOTE: Regulator system constraints must be set for this regulator before
2995  * calling this function otherwise this call will fail.
2996  */
2997 int regulator_set_current_limit(struct regulator *regulator,
2998 			       int min_uA, int max_uA)
2999 {
3000 	struct regulator_dev *rdev = regulator->rdev;
3001 	int ret;
3002 
3003 	mutex_lock(&rdev->mutex);
3004 
3005 	/* sanity check */
3006 	if (!rdev->desc->ops->set_current_limit) {
3007 		ret = -EINVAL;
3008 		goto out;
3009 	}
3010 
3011 	/* constraints check */
3012 	ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
3013 	if (ret < 0)
3014 		goto out;
3015 
3016 	ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
3017 out:
3018 	mutex_unlock(&rdev->mutex);
3019 	return ret;
3020 }
3021 EXPORT_SYMBOL_GPL(regulator_set_current_limit);
3022 
3023 static int _regulator_get_current_limit(struct regulator_dev *rdev)
3024 {
3025 	int ret;
3026 
3027 	mutex_lock(&rdev->mutex);
3028 
3029 	/* sanity check */
3030 	if (!rdev->desc->ops->get_current_limit) {
3031 		ret = -EINVAL;
3032 		goto out;
3033 	}
3034 
3035 	ret = rdev->desc->ops->get_current_limit(rdev);
3036 out:
3037 	mutex_unlock(&rdev->mutex);
3038 	return ret;
3039 }
3040 
3041 /**
3042  * regulator_get_current_limit - get regulator output current
3043  * @regulator: regulator source
3044  *
3045  * This returns the current supplied by the specified current sink in uA.
3046  *
3047  * NOTE: If the regulator is disabled it will return the current value. This
3048  * function should not be used to determine regulator state.
3049  */
3050 int regulator_get_current_limit(struct regulator *regulator)
3051 {
3052 	return _regulator_get_current_limit(regulator->rdev);
3053 }
3054 EXPORT_SYMBOL_GPL(regulator_get_current_limit);
3055 
3056 /**
3057  * regulator_set_mode - set regulator operating mode
3058  * @regulator: regulator source
3059  * @mode: operating mode - one of the REGULATOR_MODE constants
3060  *
3061  * Set regulator operating mode to increase regulator efficiency or improve
3062  * regulation performance.
3063  *
3064  * NOTE: Regulator system constraints must be set for this regulator before
3065  * calling this function otherwise this call will fail.
3066  */
3067 int regulator_set_mode(struct regulator *regulator, unsigned int mode)
3068 {
3069 	struct regulator_dev *rdev = regulator->rdev;
3070 	int ret;
3071 	int regulator_curr_mode;
3072 
3073 	mutex_lock(&rdev->mutex);
3074 
3075 	/* sanity check */
3076 	if (!rdev->desc->ops->set_mode) {
3077 		ret = -EINVAL;
3078 		goto out;
3079 	}
3080 
3081 	/* return if the same mode is requested */
3082 	if (rdev->desc->ops->get_mode) {
3083 		regulator_curr_mode = rdev->desc->ops->get_mode(rdev);
3084 		if (regulator_curr_mode == mode) {
3085 			ret = 0;
3086 			goto out;
3087 		}
3088 	}
3089 
3090 	/* constraints check */
3091 	ret = regulator_mode_constrain(rdev, &mode);
3092 	if (ret < 0)
3093 		goto out;
3094 
3095 	ret = rdev->desc->ops->set_mode(rdev, mode);
3096 out:
3097 	mutex_unlock(&rdev->mutex);
3098 	return ret;
3099 }
3100 EXPORT_SYMBOL_GPL(regulator_set_mode);
3101 
3102 static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
3103 {
3104 	int ret;
3105 
3106 	mutex_lock(&rdev->mutex);
3107 
3108 	/* sanity check */
3109 	if (!rdev->desc->ops->get_mode) {
3110 		ret = -EINVAL;
3111 		goto out;
3112 	}
3113 
3114 	ret = rdev->desc->ops->get_mode(rdev);
3115 out:
3116 	mutex_unlock(&rdev->mutex);
3117 	return ret;
3118 }
3119 
3120 /**
3121  * regulator_get_mode - get regulator operating mode
3122  * @regulator: regulator source
3123  *
3124  * Get the current regulator operating mode.
3125  */
3126 unsigned int regulator_get_mode(struct regulator *regulator)
3127 {
3128 	return _regulator_get_mode(regulator->rdev);
3129 }
3130 EXPORT_SYMBOL_GPL(regulator_get_mode);
3131 
3132 /**
3133  * regulator_set_load - set regulator load
3134  * @regulator: regulator source
3135  * @uA_load: load current
3136  *
3137  * Notifies the regulator core of a new device load. This is then used by
3138  * DRMS (if enabled by constraints) to set the most efficient regulator
3139  * operating mode for the new regulator loading.
3140  *
3141  * Consumer devices notify their supply regulator of the maximum power
3142  * they will require (can be taken from device datasheet in the power
3143  * consumption tables) when they change operational status and hence power
3144  * state. Examples of operational state changes that can affect power
3145  * consumption are :-
3146  *
3147  *    o Device is opened / closed.
3148  *    o Device I/O is about to begin or has just finished.
3149  *    o Device is idling in between work.
3150  *
3151  * This information is also exported via sysfs to userspace.
3152  *
3153  * DRMS will sum the total requested load on the regulator and change
3154  * to the most efficient operating mode if platform constraints allow.
3155  *
3156  * On error a negative errno is returned.
3157  */
3158 int regulator_set_load(struct regulator *regulator, int uA_load)
3159 {
3160 	struct regulator_dev *rdev = regulator->rdev;
3161 	int ret;
3162 
3163 	mutex_lock(&rdev->mutex);
3164 	regulator->uA_load = uA_load;
3165 	ret = drms_uA_update(rdev);
3166 	mutex_unlock(&rdev->mutex);
3167 
3168 	return ret;
3169 }
3170 EXPORT_SYMBOL_GPL(regulator_set_load);
3171 
3172 /**
3173  * regulator_allow_bypass - allow the regulator to go into bypass mode
3174  *
3175  * @regulator: Regulator to configure
3176  * @enable: enable or disable bypass mode
3177  *
3178  * Allow the regulator to go into bypass mode if all other consumers
3179  * for the regulator also enable bypass mode and the machine
3180  * constraints allow this.  Bypass mode means that the regulator is
3181  * simply passing the input directly to the output with no regulation.
3182  */
3183 int regulator_allow_bypass(struct regulator *regulator, bool enable)
3184 {
3185 	struct regulator_dev *rdev = regulator->rdev;
3186 	int ret = 0;
3187 
3188 	if (!rdev->desc->ops->set_bypass)
3189 		return 0;
3190 
3191 	if (rdev->constraints &&
3192 	    !(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_BYPASS))
3193 		return 0;
3194 
3195 	mutex_lock(&rdev->mutex);
3196 
3197 	if (enable && !regulator->bypass) {
3198 		rdev->bypass_count++;
3199 
3200 		if (rdev->bypass_count == rdev->open_count) {
3201 			ret = rdev->desc->ops->set_bypass(rdev, enable);
3202 			if (ret != 0)
3203 				rdev->bypass_count--;
3204 		}
3205 
3206 	} else if (!enable && regulator->bypass) {
3207 		rdev->bypass_count--;
3208 
3209 		if (rdev->bypass_count != rdev->open_count) {
3210 			ret = rdev->desc->ops->set_bypass(rdev, enable);
3211 			if (ret != 0)
3212 				rdev->bypass_count++;
3213 		}
3214 	}
3215 
3216 	if (ret == 0)
3217 		regulator->bypass = enable;
3218 
3219 	mutex_unlock(&rdev->mutex);
3220 
3221 	return ret;
3222 }
3223 EXPORT_SYMBOL_GPL(regulator_allow_bypass);
3224 
3225 /**
3226  * regulator_register_notifier - register regulator event notifier
3227  * @regulator: regulator source
3228  * @nb: notifier block
3229  *
3230  * Register notifier block to receive regulator events.
3231  */
3232 int regulator_register_notifier(struct regulator *regulator,
3233 			      struct notifier_block *nb)
3234 {
3235 	return blocking_notifier_chain_register(&regulator->rdev->notifier,
3236 						nb);
3237 }
3238 EXPORT_SYMBOL_GPL(regulator_register_notifier);
3239 
3240 /**
3241  * regulator_unregister_notifier - unregister regulator event notifier
3242  * @regulator: regulator source
3243  * @nb: notifier block
3244  *
3245  * Unregister regulator event notifier block.
3246  */
3247 int regulator_unregister_notifier(struct regulator *regulator,
3248 				struct notifier_block *nb)
3249 {
3250 	return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
3251 						  nb);
3252 }
3253 EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
3254 
3255 /* notify regulator consumers and downstream regulator consumers.
3256  * Note mutex must be held by caller.
3257  */
3258 static int _notifier_call_chain(struct regulator_dev *rdev,
3259 				  unsigned long event, void *data)
3260 {
3261 	/* call rdev chain first */
3262 	return blocking_notifier_call_chain(&rdev->notifier, event, data);
3263 }
3264 
3265 /**
3266  * regulator_bulk_get - get multiple regulator consumers
3267  *
3268  * @dev:           Device to supply
3269  * @num_consumers: Number of consumers to register
3270  * @consumers:     Configuration of consumers; clients are stored here.
3271  *
3272  * @return 0 on success, an errno on failure.
3273  *
3274  * This helper function allows drivers to get several regulator
3275  * consumers in one operation.  If any of the regulators cannot be
3276  * acquired then any regulators that were allocated will be freed
3277  * before returning to the caller.
3278  */
3279 int regulator_bulk_get(struct device *dev, int num_consumers,
3280 		       struct regulator_bulk_data *consumers)
3281 {
3282 	int i;
3283 	int ret;
3284 
3285 	for (i = 0; i < num_consumers; i++)
3286 		consumers[i].consumer = NULL;
3287 
3288 	for (i = 0; i < num_consumers; i++) {
3289 		consumers[i].consumer = regulator_get(dev,
3290 						      consumers[i].supply);
3291 		if (IS_ERR(consumers[i].consumer)) {
3292 			ret = PTR_ERR(consumers[i].consumer);
3293 			dev_err(dev, "Failed to get supply '%s': %d\n",
3294 				consumers[i].supply, ret);
3295 			consumers[i].consumer = NULL;
3296 			goto err;
3297 		}
3298 	}
3299 
3300 	return 0;
3301 
3302 err:
3303 	while (--i >= 0)
3304 		regulator_put(consumers[i].consumer);
3305 
3306 	return ret;
3307 }
3308 EXPORT_SYMBOL_GPL(regulator_bulk_get);
3309 
3310 static void regulator_bulk_enable_async(void *data, async_cookie_t cookie)
3311 {
3312 	struct regulator_bulk_data *bulk = data;
3313 
3314 	bulk->ret = regulator_enable(bulk->consumer);
3315 }
3316 
3317 /**
3318  * regulator_bulk_enable - enable multiple regulator consumers
3319  *
3320  * @num_consumers: Number of consumers
3321  * @consumers:     Consumer data; clients are stored here.
3322  * @return         0 on success, an errno on failure
3323  *
3324  * This convenience API allows consumers to enable multiple regulator
3325  * clients in a single API call.  If any consumers cannot be enabled
3326  * then any others that were enabled will be disabled again prior to
3327  * return.
3328  */
3329 int regulator_bulk_enable(int num_consumers,
3330 			  struct regulator_bulk_data *consumers)
3331 {
3332 	ASYNC_DOMAIN_EXCLUSIVE(async_domain);
3333 	int i;
3334 	int ret = 0;
3335 
3336 	for (i = 0; i < num_consumers; i++) {
3337 		if (consumers[i].consumer->always_on)
3338 			consumers[i].ret = 0;
3339 		else
3340 			async_schedule_domain(regulator_bulk_enable_async,
3341 					      &consumers[i], &async_domain);
3342 	}
3343 
3344 	async_synchronize_full_domain(&async_domain);
3345 
3346 	/* If any consumer failed we need to unwind any that succeeded */
3347 	for (i = 0; i < num_consumers; i++) {
3348 		if (consumers[i].ret != 0) {
3349 			ret = consumers[i].ret;
3350 			goto err;
3351 		}
3352 	}
3353 
3354 	return 0;
3355 
3356 err:
3357 	for (i = 0; i < num_consumers; i++) {
3358 		if (consumers[i].ret < 0)
3359 			pr_err("Failed to enable %s: %d\n", consumers[i].supply,
3360 			       consumers[i].ret);
3361 		else
3362 			regulator_disable(consumers[i].consumer);
3363 	}
3364 
3365 	return ret;
3366 }
3367 EXPORT_SYMBOL_GPL(regulator_bulk_enable);
3368 
3369 /**
3370  * regulator_bulk_disable - disable multiple regulator consumers
3371  *
3372  * @num_consumers: Number of consumers
3373  * @consumers:     Consumer data; clients are stored here.
3374  * @return         0 on success, an errno on failure
3375  *
3376  * This convenience API allows consumers to disable multiple regulator
3377  * clients in a single API call.  If any consumers cannot be disabled
3378  * then any others that were disabled will be enabled again prior to
3379  * return.
3380  */
3381 int regulator_bulk_disable(int num_consumers,
3382 			   struct regulator_bulk_data *consumers)
3383 {
3384 	int i;
3385 	int ret, r;
3386 
3387 	for (i = num_consumers - 1; i >= 0; --i) {
3388 		ret = regulator_disable(consumers[i].consumer);
3389 		if (ret != 0)
3390 			goto err;
3391 	}
3392 
3393 	return 0;
3394 
3395 err:
3396 	pr_err("Failed to disable %s: %d\n", consumers[i].supply, ret);
3397 	for (++i; i < num_consumers; ++i) {
3398 		r = regulator_enable(consumers[i].consumer);
3399 		if (r != 0)
3400 			pr_err("Failed to reename %s: %d\n",
3401 			       consumers[i].supply, r);
3402 	}
3403 
3404 	return ret;
3405 }
3406 EXPORT_SYMBOL_GPL(regulator_bulk_disable);
3407 
3408 /**
3409  * regulator_bulk_force_disable - force disable multiple regulator consumers
3410  *
3411  * @num_consumers: Number of consumers
3412  * @consumers:     Consumer data; clients are stored here.
3413  * @return         0 on success, an errno on failure
3414  *
3415  * This convenience API allows consumers to forcibly disable multiple regulator
3416  * clients in a single API call.
3417  * NOTE: This should be used for situations when device damage will
3418  * likely occur if the regulators are not disabled (e.g. over temp).
3419  * Although regulator_force_disable function call for some consumers can
3420  * return error numbers, the function is called for all consumers.
3421  */
3422 int regulator_bulk_force_disable(int num_consumers,
3423 			   struct regulator_bulk_data *consumers)
3424 {
3425 	int i;
3426 	int ret;
3427 
3428 	for (i = 0; i < num_consumers; i++)
3429 		consumers[i].ret =
3430 			    regulator_force_disable(consumers[i].consumer);
3431 
3432 	for (i = 0; i < num_consumers; i++) {
3433 		if (consumers[i].ret != 0) {
3434 			ret = consumers[i].ret;
3435 			goto out;
3436 		}
3437 	}
3438 
3439 	return 0;
3440 out:
3441 	return ret;
3442 }
3443 EXPORT_SYMBOL_GPL(regulator_bulk_force_disable);
3444 
3445 /**
3446  * regulator_bulk_free - free multiple regulator consumers
3447  *
3448  * @num_consumers: Number of consumers
3449  * @consumers:     Consumer data; clients are stored here.
3450  *
3451  * This convenience API allows consumers to free multiple regulator
3452  * clients in a single API call.
3453  */
3454 void regulator_bulk_free(int num_consumers,
3455 			 struct regulator_bulk_data *consumers)
3456 {
3457 	int i;
3458 
3459 	for (i = 0; i < num_consumers; i++) {
3460 		regulator_put(consumers[i].consumer);
3461 		consumers[i].consumer = NULL;
3462 	}
3463 }
3464 EXPORT_SYMBOL_GPL(regulator_bulk_free);
3465 
3466 /**
3467  * regulator_notifier_call_chain - call regulator event notifier
3468  * @rdev: regulator source
3469  * @event: notifier block
3470  * @data: callback-specific data.
3471  *
3472  * Called by regulator drivers to notify clients a regulator event has
3473  * occurred. We also notify regulator clients downstream.
3474  * Note lock must be held by caller.
3475  */
3476 int regulator_notifier_call_chain(struct regulator_dev *rdev,
3477 				  unsigned long event, void *data)
3478 {
3479 	lockdep_assert_held_once(&rdev->mutex);
3480 
3481 	_notifier_call_chain(rdev, event, data);
3482 	return NOTIFY_DONE;
3483 
3484 }
3485 EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
3486 
3487 /**
3488  * regulator_mode_to_status - convert a regulator mode into a status
3489  *
3490  * @mode: Mode to convert
3491  *
3492  * Convert a regulator mode into a status.
3493  */
3494 int regulator_mode_to_status(unsigned int mode)
3495 {
3496 	switch (mode) {
3497 	case REGULATOR_MODE_FAST:
3498 		return REGULATOR_STATUS_FAST;
3499 	case REGULATOR_MODE_NORMAL:
3500 		return REGULATOR_STATUS_NORMAL;
3501 	case REGULATOR_MODE_IDLE:
3502 		return REGULATOR_STATUS_IDLE;
3503 	case REGULATOR_MODE_STANDBY:
3504 		return REGULATOR_STATUS_STANDBY;
3505 	default:
3506 		return REGULATOR_STATUS_UNDEFINED;
3507 	}
3508 }
3509 EXPORT_SYMBOL_GPL(regulator_mode_to_status);
3510 
3511 static struct attribute *regulator_dev_attrs[] = {
3512 	&dev_attr_name.attr,
3513 	&dev_attr_num_users.attr,
3514 	&dev_attr_type.attr,
3515 	&dev_attr_microvolts.attr,
3516 	&dev_attr_microamps.attr,
3517 	&dev_attr_opmode.attr,
3518 	&dev_attr_state.attr,
3519 	&dev_attr_status.attr,
3520 	&dev_attr_bypass.attr,
3521 	&dev_attr_requested_microamps.attr,
3522 	&dev_attr_min_microvolts.attr,
3523 	&dev_attr_max_microvolts.attr,
3524 	&dev_attr_min_microamps.attr,
3525 	&dev_attr_max_microamps.attr,
3526 	&dev_attr_suspend_standby_state.attr,
3527 	&dev_attr_suspend_mem_state.attr,
3528 	&dev_attr_suspend_disk_state.attr,
3529 	&dev_attr_suspend_standby_microvolts.attr,
3530 	&dev_attr_suspend_mem_microvolts.attr,
3531 	&dev_attr_suspend_disk_microvolts.attr,
3532 	&dev_attr_suspend_standby_mode.attr,
3533 	&dev_attr_suspend_mem_mode.attr,
3534 	&dev_attr_suspend_disk_mode.attr,
3535 	NULL
3536 };
3537 
3538 /*
3539  * To avoid cluttering sysfs (and memory) with useless state, only
3540  * create attributes that can be meaningfully displayed.
3541  */
3542 static umode_t regulator_attr_is_visible(struct kobject *kobj,
3543 					 struct attribute *attr, int idx)
3544 {
3545 	struct device *dev = kobj_to_dev(kobj);
3546 	struct regulator_dev *rdev = container_of(dev, struct regulator_dev, dev);
3547 	const struct regulator_ops *ops = rdev->desc->ops;
3548 	umode_t mode = attr->mode;
3549 
3550 	/* these three are always present */
3551 	if (attr == &dev_attr_name.attr ||
3552 	    attr == &dev_attr_num_users.attr ||
3553 	    attr == &dev_attr_type.attr)
3554 		return mode;
3555 
3556 	/* some attributes need specific methods to be displayed */
3557 	if (attr == &dev_attr_microvolts.attr) {
3558 		if ((ops->get_voltage && ops->get_voltage(rdev) >= 0) ||
3559 		    (ops->get_voltage_sel && ops->get_voltage_sel(rdev) >= 0) ||
3560 		    (ops->list_voltage && ops->list_voltage(rdev, 0) >= 0) ||
3561 		    (rdev->desc->fixed_uV && rdev->desc->n_voltages == 1))
3562 			return mode;
3563 		return 0;
3564 	}
3565 
3566 	if (attr == &dev_attr_microamps.attr)
3567 		return ops->get_current_limit ? mode : 0;
3568 
3569 	if (attr == &dev_attr_opmode.attr)
3570 		return ops->get_mode ? mode : 0;
3571 
3572 	if (attr == &dev_attr_state.attr)
3573 		return (rdev->ena_pin || ops->is_enabled) ? mode : 0;
3574 
3575 	if (attr == &dev_attr_status.attr)
3576 		return ops->get_status ? mode : 0;
3577 
3578 	if (attr == &dev_attr_bypass.attr)
3579 		return ops->get_bypass ? mode : 0;
3580 
3581 	/* some attributes are type-specific */
3582 	if (attr == &dev_attr_requested_microamps.attr)
3583 		return rdev->desc->type == REGULATOR_CURRENT ? mode : 0;
3584 
3585 	/* constraints need specific supporting methods */
3586 	if (attr == &dev_attr_min_microvolts.attr ||
3587 	    attr == &dev_attr_max_microvolts.attr)
3588 		return (ops->set_voltage || ops->set_voltage_sel) ? mode : 0;
3589 
3590 	if (attr == &dev_attr_min_microamps.attr ||
3591 	    attr == &dev_attr_max_microamps.attr)
3592 		return ops->set_current_limit ? mode : 0;
3593 
3594 	if (attr == &dev_attr_suspend_standby_state.attr ||
3595 	    attr == &dev_attr_suspend_mem_state.attr ||
3596 	    attr == &dev_attr_suspend_disk_state.attr)
3597 		return mode;
3598 
3599 	if (attr == &dev_attr_suspend_standby_microvolts.attr ||
3600 	    attr == &dev_attr_suspend_mem_microvolts.attr ||
3601 	    attr == &dev_attr_suspend_disk_microvolts.attr)
3602 		return ops->set_suspend_voltage ? mode : 0;
3603 
3604 	if (attr == &dev_attr_suspend_standby_mode.attr ||
3605 	    attr == &dev_attr_suspend_mem_mode.attr ||
3606 	    attr == &dev_attr_suspend_disk_mode.attr)
3607 		return ops->set_suspend_mode ? mode : 0;
3608 
3609 	return mode;
3610 }
3611 
3612 static const struct attribute_group regulator_dev_group = {
3613 	.attrs = regulator_dev_attrs,
3614 	.is_visible = regulator_attr_is_visible,
3615 };
3616 
3617 static const struct attribute_group *regulator_dev_groups[] = {
3618 	&regulator_dev_group,
3619 	NULL
3620 };
3621 
3622 static void regulator_dev_release(struct device *dev)
3623 {
3624 	struct regulator_dev *rdev = dev_get_drvdata(dev);
3625 
3626 	kfree(rdev->constraints);
3627 	of_node_put(rdev->dev.of_node);
3628 	kfree(rdev);
3629 }
3630 
3631 static struct class regulator_class = {
3632 	.name = "regulator",
3633 	.dev_release = regulator_dev_release,
3634 	.dev_groups = regulator_dev_groups,
3635 };
3636 
3637 static void rdev_init_debugfs(struct regulator_dev *rdev)
3638 {
3639 	struct device *parent = rdev->dev.parent;
3640 	const char *rname = rdev_get_name(rdev);
3641 	char name[NAME_MAX];
3642 
3643 	/* Avoid duplicate debugfs directory names */
3644 	if (parent && rname == rdev->desc->name) {
3645 		snprintf(name, sizeof(name), "%s-%s", dev_name(parent),
3646 			 rname);
3647 		rname = name;
3648 	}
3649 
3650 	rdev->debugfs = debugfs_create_dir(rname, debugfs_root);
3651 	if (!rdev->debugfs) {
3652 		rdev_warn(rdev, "Failed to create debugfs directory\n");
3653 		return;
3654 	}
3655 
3656 	debugfs_create_u32("use_count", 0444, rdev->debugfs,
3657 			   &rdev->use_count);
3658 	debugfs_create_u32("open_count", 0444, rdev->debugfs,
3659 			   &rdev->open_count);
3660 	debugfs_create_u32("bypass_count", 0444, rdev->debugfs,
3661 			   &rdev->bypass_count);
3662 }
3663 
3664 /**
3665  * regulator_register - register regulator
3666  * @regulator_desc: regulator to register
3667  * @cfg: runtime configuration for regulator
3668  *
3669  * Called by regulator drivers to register a regulator.
3670  * Returns a valid pointer to struct regulator_dev on success
3671  * or an ERR_PTR() on error.
3672  */
3673 struct regulator_dev *
3674 regulator_register(const struct regulator_desc *regulator_desc,
3675 		   const struct regulator_config *cfg)
3676 {
3677 	const struct regulation_constraints *constraints = NULL;
3678 	const struct regulator_init_data *init_data;
3679 	struct regulator_config *config = NULL;
3680 	static atomic_t regulator_no = ATOMIC_INIT(-1);
3681 	struct regulator_dev *rdev;
3682 	struct device *dev;
3683 	int ret, i;
3684 
3685 	if (regulator_desc == NULL || cfg == NULL)
3686 		return ERR_PTR(-EINVAL);
3687 
3688 	dev = cfg->dev;
3689 	WARN_ON(!dev);
3690 
3691 	if (regulator_desc->name == NULL || regulator_desc->ops == NULL)
3692 		return ERR_PTR(-EINVAL);
3693 
3694 	if (regulator_desc->type != REGULATOR_VOLTAGE &&
3695 	    regulator_desc->type != REGULATOR_CURRENT)
3696 		return ERR_PTR(-EINVAL);
3697 
3698 	/* Only one of each should be implemented */
3699 	WARN_ON(regulator_desc->ops->get_voltage &&
3700 		regulator_desc->ops->get_voltage_sel);
3701 	WARN_ON(regulator_desc->ops->set_voltage &&
3702 		regulator_desc->ops->set_voltage_sel);
3703 
3704 	/* If we're using selectors we must implement list_voltage. */
3705 	if (regulator_desc->ops->get_voltage_sel &&
3706 	    !regulator_desc->ops->list_voltage) {
3707 		return ERR_PTR(-EINVAL);
3708 	}
3709 	if (regulator_desc->ops->set_voltage_sel &&
3710 	    !regulator_desc->ops->list_voltage) {
3711 		return ERR_PTR(-EINVAL);
3712 	}
3713 
3714 	rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
3715 	if (rdev == NULL)
3716 		return ERR_PTR(-ENOMEM);
3717 
3718 	/*
3719 	 * Duplicate the config so the driver could override it after
3720 	 * parsing init data.
3721 	 */
3722 	config = kmemdup(cfg, sizeof(*cfg), GFP_KERNEL);
3723 	if (config == NULL) {
3724 		kfree(rdev);
3725 		return ERR_PTR(-ENOMEM);
3726 	}
3727 
3728 	init_data = regulator_of_get_init_data(dev, regulator_desc, config,
3729 					       &rdev->dev.of_node);
3730 	if (!init_data) {
3731 		init_data = config->init_data;
3732 		rdev->dev.of_node = of_node_get(config->of_node);
3733 	}
3734 
3735 	mutex_lock(&regulator_list_mutex);
3736 
3737 	mutex_init(&rdev->mutex);
3738 	rdev->reg_data = config->driver_data;
3739 	rdev->owner = regulator_desc->owner;
3740 	rdev->desc = regulator_desc;
3741 	if (config->regmap)
3742 		rdev->regmap = config->regmap;
3743 	else if (dev_get_regmap(dev, NULL))
3744 		rdev->regmap = dev_get_regmap(dev, NULL);
3745 	else if (dev->parent)
3746 		rdev->regmap = dev_get_regmap(dev->parent, NULL);
3747 	INIT_LIST_HEAD(&rdev->consumer_list);
3748 	INIT_LIST_HEAD(&rdev->list);
3749 	BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
3750 	INIT_DELAYED_WORK(&rdev->disable_work, regulator_disable_work);
3751 
3752 	/* preform any regulator specific init */
3753 	if (init_data && init_data->regulator_init) {
3754 		ret = init_data->regulator_init(rdev->reg_data);
3755 		if (ret < 0)
3756 			goto clean;
3757 	}
3758 
3759 	/* register with sysfs */
3760 	rdev->dev.class = &regulator_class;
3761 	rdev->dev.parent = dev;
3762 	dev_set_name(&rdev->dev, "regulator.%lu",
3763 		    (unsigned long) atomic_inc_return(&regulator_no));
3764 	ret = device_register(&rdev->dev);
3765 	if (ret != 0) {
3766 		put_device(&rdev->dev);
3767 		goto clean;
3768 	}
3769 
3770 	dev_set_drvdata(&rdev->dev, rdev);
3771 
3772 	if ((config->ena_gpio || config->ena_gpio_initialized) &&
3773 	    gpio_is_valid(config->ena_gpio)) {
3774 		ret = regulator_ena_gpio_request(rdev, config);
3775 		if (ret != 0) {
3776 			rdev_err(rdev, "Failed to request enable GPIO%d: %d\n",
3777 				 config->ena_gpio, ret);
3778 			goto wash;
3779 		}
3780 	}
3781 
3782 	/* set regulator constraints */
3783 	if (init_data)
3784 		constraints = &init_data->constraints;
3785 
3786 	ret = set_machine_constraints(rdev, constraints);
3787 	if (ret < 0)
3788 		goto scrub;
3789 
3790 	if (init_data && init_data->supply_regulator)
3791 		rdev->supply_name = init_data->supply_regulator;
3792 	else if (regulator_desc->supply_name)
3793 		rdev->supply_name = regulator_desc->supply_name;
3794 
3795 	/* add consumers devices */
3796 	if (init_data) {
3797 		for (i = 0; i < init_data->num_consumer_supplies; i++) {
3798 			ret = set_consumer_device_supply(rdev,
3799 				init_data->consumer_supplies[i].dev_name,
3800 				init_data->consumer_supplies[i].supply);
3801 			if (ret < 0) {
3802 				dev_err(dev, "Failed to set supply %s\n",
3803 					init_data->consumer_supplies[i].supply);
3804 				goto unset_supplies;
3805 			}
3806 		}
3807 	}
3808 
3809 	list_add(&rdev->list, &regulator_list);
3810 
3811 	rdev_init_debugfs(rdev);
3812 out:
3813 	mutex_unlock(&regulator_list_mutex);
3814 	kfree(config);
3815 	return rdev;
3816 
3817 unset_supplies:
3818 	unset_regulator_supplies(rdev);
3819 
3820 scrub:
3821 	regulator_ena_gpio_free(rdev);
3822 	kfree(rdev->constraints);
3823 wash:
3824 	device_unregister(&rdev->dev);
3825 	/* device core frees rdev */
3826 	rdev = ERR_PTR(ret);
3827 	goto out;
3828 
3829 clean:
3830 	kfree(rdev);
3831 	rdev = ERR_PTR(ret);
3832 	goto out;
3833 }
3834 EXPORT_SYMBOL_GPL(regulator_register);
3835 
3836 /**
3837  * regulator_unregister - unregister regulator
3838  * @rdev: regulator to unregister
3839  *
3840  * Called by regulator drivers to unregister a regulator.
3841  */
3842 void regulator_unregister(struct regulator_dev *rdev)
3843 {
3844 	if (rdev == NULL)
3845 		return;
3846 
3847 	if (rdev->supply) {
3848 		while (rdev->use_count--)
3849 			regulator_disable(rdev->supply);
3850 		regulator_put(rdev->supply);
3851 	}
3852 	mutex_lock(&regulator_list_mutex);
3853 	debugfs_remove_recursive(rdev->debugfs);
3854 	flush_work(&rdev->disable_work.work);
3855 	WARN_ON(rdev->open_count);
3856 	unset_regulator_supplies(rdev);
3857 	list_del(&rdev->list);
3858 	mutex_unlock(&regulator_list_mutex);
3859 	regulator_ena_gpio_free(rdev);
3860 	device_unregister(&rdev->dev);
3861 }
3862 EXPORT_SYMBOL_GPL(regulator_unregister);
3863 
3864 /**
3865  * regulator_suspend_prepare - prepare regulators for system wide suspend
3866  * @state: system suspend state
3867  *
3868  * Configure each regulator with it's suspend operating parameters for state.
3869  * This will usually be called by machine suspend code prior to supending.
3870  */
3871 int regulator_suspend_prepare(suspend_state_t state)
3872 {
3873 	struct regulator_dev *rdev;
3874 	int ret = 0;
3875 
3876 	/* ON is handled by regulator active state */
3877 	if (state == PM_SUSPEND_ON)
3878 		return -EINVAL;
3879 
3880 	mutex_lock(&regulator_list_mutex);
3881 	list_for_each_entry(rdev, &regulator_list, list) {
3882 
3883 		mutex_lock(&rdev->mutex);
3884 		ret = suspend_prepare(rdev, state);
3885 		mutex_unlock(&rdev->mutex);
3886 
3887 		if (ret < 0) {
3888 			rdev_err(rdev, "failed to prepare\n");
3889 			goto out;
3890 		}
3891 	}
3892 out:
3893 	mutex_unlock(&regulator_list_mutex);
3894 	return ret;
3895 }
3896 EXPORT_SYMBOL_GPL(regulator_suspend_prepare);
3897 
3898 /**
3899  * regulator_suspend_finish - resume regulators from system wide suspend
3900  *
3901  * Turn on regulators that might be turned off by regulator_suspend_prepare
3902  * and that should be turned on according to the regulators properties.
3903  */
3904 int regulator_suspend_finish(void)
3905 {
3906 	struct regulator_dev *rdev;
3907 	int ret = 0, error;
3908 
3909 	mutex_lock(&regulator_list_mutex);
3910 	list_for_each_entry(rdev, &regulator_list, list) {
3911 		mutex_lock(&rdev->mutex);
3912 		if (rdev->use_count > 0  || rdev->constraints->always_on) {
3913 			if (!_regulator_is_enabled(rdev)) {
3914 				error = _regulator_do_enable(rdev);
3915 				if (error)
3916 					ret = error;
3917 			}
3918 		} else {
3919 			if (!have_full_constraints())
3920 				goto unlock;
3921 			if (!_regulator_is_enabled(rdev))
3922 				goto unlock;
3923 
3924 			error = _regulator_do_disable(rdev);
3925 			if (error)
3926 				ret = error;
3927 		}
3928 unlock:
3929 		mutex_unlock(&rdev->mutex);
3930 	}
3931 	mutex_unlock(&regulator_list_mutex);
3932 	return ret;
3933 }
3934 EXPORT_SYMBOL_GPL(regulator_suspend_finish);
3935 
3936 /**
3937  * regulator_has_full_constraints - the system has fully specified constraints
3938  *
3939  * Calling this function will cause the regulator API to disable all
3940  * regulators which have a zero use count and don't have an always_on
3941  * constraint in a late_initcall.
3942  *
3943  * The intention is that this will become the default behaviour in a
3944  * future kernel release so users are encouraged to use this facility
3945  * now.
3946  */
3947 void regulator_has_full_constraints(void)
3948 {
3949 	has_full_constraints = 1;
3950 }
3951 EXPORT_SYMBOL_GPL(regulator_has_full_constraints);
3952 
3953 /**
3954  * rdev_get_drvdata - get rdev regulator driver data
3955  * @rdev: regulator
3956  *
3957  * Get rdev regulator driver private data. This call can be used in the
3958  * regulator driver context.
3959  */
3960 void *rdev_get_drvdata(struct regulator_dev *rdev)
3961 {
3962 	return rdev->reg_data;
3963 }
3964 EXPORT_SYMBOL_GPL(rdev_get_drvdata);
3965 
3966 /**
3967  * regulator_get_drvdata - get regulator driver data
3968  * @regulator: regulator
3969  *
3970  * Get regulator driver private data. This call can be used in the consumer
3971  * driver context when non API regulator specific functions need to be called.
3972  */
3973 void *regulator_get_drvdata(struct regulator *regulator)
3974 {
3975 	return regulator->rdev->reg_data;
3976 }
3977 EXPORT_SYMBOL_GPL(regulator_get_drvdata);
3978 
3979 /**
3980  * regulator_set_drvdata - set regulator driver data
3981  * @regulator: regulator
3982  * @data: data
3983  */
3984 void regulator_set_drvdata(struct regulator *regulator, void *data)
3985 {
3986 	regulator->rdev->reg_data = data;
3987 }
3988 EXPORT_SYMBOL_GPL(regulator_set_drvdata);
3989 
3990 /**
3991  * regulator_get_id - get regulator ID
3992  * @rdev: regulator
3993  */
3994 int rdev_get_id(struct regulator_dev *rdev)
3995 {
3996 	return rdev->desc->id;
3997 }
3998 EXPORT_SYMBOL_GPL(rdev_get_id);
3999 
4000 struct device *rdev_get_dev(struct regulator_dev *rdev)
4001 {
4002 	return &rdev->dev;
4003 }
4004 EXPORT_SYMBOL_GPL(rdev_get_dev);
4005 
4006 void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
4007 {
4008 	return reg_init_data->driver_data;
4009 }
4010 EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
4011 
4012 #ifdef CONFIG_DEBUG_FS
4013 static ssize_t supply_map_read_file(struct file *file, char __user *user_buf,
4014 				    size_t count, loff_t *ppos)
4015 {
4016 	char *buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
4017 	ssize_t len, ret = 0;
4018 	struct regulator_map *map;
4019 
4020 	if (!buf)
4021 		return -ENOMEM;
4022 
4023 	list_for_each_entry(map, &regulator_map_list, list) {
4024 		len = snprintf(buf + ret, PAGE_SIZE - ret,
4025 			       "%s -> %s.%s\n",
4026 			       rdev_get_name(map->regulator), map->dev_name,
4027 			       map->supply);
4028 		if (len >= 0)
4029 			ret += len;
4030 		if (ret > PAGE_SIZE) {
4031 			ret = PAGE_SIZE;
4032 			break;
4033 		}
4034 	}
4035 
4036 	ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
4037 
4038 	kfree(buf);
4039 
4040 	return ret;
4041 }
4042 #endif
4043 
4044 static const struct file_operations supply_map_fops = {
4045 #ifdef CONFIG_DEBUG_FS
4046 	.read = supply_map_read_file,
4047 	.llseek = default_llseek,
4048 #endif
4049 };
4050 
4051 #ifdef CONFIG_DEBUG_FS
4052 static void regulator_summary_show_subtree(struct seq_file *s,
4053 					   struct regulator_dev *rdev,
4054 					   int level)
4055 {
4056 	struct list_head *list = s->private;
4057 	struct regulator_dev *child;
4058 	struct regulation_constraints *c;
4059 	struct regulator *consumer;
4060 
4061 	if (!rdev)
4062 		return;
4063 
4064 	seq_printf(s, "%*s%-*s %3d %4d %6d ",
4065 		   level * 3 + 1, "",
4066 		   30 - level * 3, rdev_get_name(rdev),
4067 		   rdev->use_count, rdev->open_count, rdev->bypass_count);
4068 
4069 	seq_printf(s, "%5dmV ", _regulator_get_voltage(rdev) / 1000);
4070 	seq_printf(s, "%5dmA ", _regulator_get_current_limit(rdev) / 1000);
4071 
4072 	c = rdev->constraints;
4073 	if (c) {
4074 		switch (rdev->desc->type) {
4075 		case REGULATOR_VOLTAGE:
4076 			seq_printf(s, "%5dmV %5dmV ",
4077 				   c->min_uV / 1000, c->max_uV / 1000);
4078 			break;
4079 		case REGULATOR_CURRENT:
4080 			seq_printf(s, "%5dmA %5dmA ",
4081 				   c->min_uA / 1000, c->max_uA / 1000);
4082 			break;
4083 		}
4084 	}
4085 
4086 	seq_puts(s, "\n");
4087 
4088 	list_for_each_entry(consumer, &rdev->consumer_list, list) {
4089 		if (consumer->dev->class == &regulator_class)
4090 			continue;
4091 
4092 		seq_printf(s, "%*s%-*s ",
4093 			   (level + 1) * 3 + 1, "",
4094 			   30 - (level + 1) * 3, dev_name(consumer->dev));
4095 
4096 		switch (rdev->desc->type) {
4097 		case REGULATOR_VOLTAGE:
4098 			seq_printf(s, "%37dmV %5dmV",
4099 				   consumer->min_uV / 1000,
4100 				   consumer->max_uV / 1000);
4101 			break;
4102 		case REGULATOR_CURRENT:
4103 			break;
4104 		}
4105 
4106 		seq_puts(s, "\n");
4107 	}
4108 
4109 	list_for_each_entry(child, list, list) {
4110 		/* handle only non-root regulators supplied by current rdev */
4111 		if (!child->supply || child->supply->rdev != rdev)
4112 			continue;
4113 
4114 		regulator_summary_show_subtree(s, child, level + 1);
4115 	}
4116 }
4117 
4118 static int regulator_summary_show(struct seq_file *s, void *data)
4119 {
4120 	struct list_head *list = s->private;
4121 	struct regulator_dev *rdev;
4122 
4123 	seq_puts(s, " regulator                      use open bypass voltage current     min     max\n");
4124 	seq_puts(s, "-------------------------------------------------------------------------------\n");
4125 
4126 	mutex_lock(&regulator_list_mutex);
4127 
4128 	list_for_each_entry(rdev, list, list) {
4129 		if (rdev->supply)
4130 			continue;
4131 
4132 		regulator_summary_show_subtree(s, rdev, 0);
4133 	}
4134 
4135 	mutex_unlock(&regulator_list_mutex);
4136 
4137 	return 0;
4138 }
4139 
4140 static int regulator_summary_open(struct inode *inode, struct file *file)
4141 {
4142 	return single_open(file, regulator_summary_show, inode->i_private);
4143 }
4144 #endif
4145 
4146 static const struct file_operations regulator_summary_fops = {
4147 #ifdef CONFIG_DEBUG_FS
4148 	.open		= regulator_summary_open,
4149 	.read		= seq_read,
4150 	.llseek		= seq_lseek,
4151 	.release	= single_release,
4152 #endif
4153 };
4154 
4155 static int __init regulator_init(void)
4156 {
4157 	int ret;
4158 
4159 	ret = class_register(&regulator_class);
4160 
4161 	debugfs_root = debugfs_create_dir("regulator", NULL);
4162 	if (!debugfs_root)
4163 		pr_warn("regulator: Failed to create debugfs directory\n");
4164 
4165 	debugfs_create_file("supply_map", 0444, debugfs_root, NULL,
4166 			    &supply_map_fops);
4167 
4168 	debugfs_create_file("regulator_summary", 0444, debugfs_root,
4169 			    &regulator_list, &regulator_summary_fops);
4170 
4171 	regulator_dummy_init();
4172 
4173 	return ret;
4174 }
4175 
4176 /* init early to allow our consumers to complete system booting */
4177 core_initcall(regulator_init);
4178 
4179 static int __init regulator_late_cleanup(struct device *dev, void *data)
4180 {
4181 	struct regulator_dev *rdev = dev_to_rdev(dev);
4182 	const struct regulator_ops *ops = rdev->desc->ops;
4183 	struct regulation_constraints *c = rdev->constraints;
4184 	int enabled, ret;
4185 
4186 	if (c && c->always_on)
4187 		return 0;
4188 
4189 	if (c && !(c->valid_ops_mask & REGULATOR_CHANGE_STATUS))
4190 		return 0;
4191 
4192 	mutex_lock(&rdev->mutex);
4193 
4194 	if (rdev->use_count)
4195 		goto unlock;
4196 
4197 	/* If we can't read the status assume it's on. */
4198 	if (ops->is_enabled)
4199 		enabled = ops->is_enabled(rdev);
4200 	else
4201 		enabled = 1;
4202 
4203 	if (!enabled)
4204 		goto unlock;
4205 
4206 	if (have_full_constraints()) {
4207 		/* We log since this may kill the system if it goes
4208 		 * wrong. */
4209 		rdev_info(rdev, "disabling\n");
4210 		ret = _regulator_do_disable(rdev);
4211 		if (ret != 0)
4212 			rdev_err(rdev, "couldn't disable: %d\n", ret);
4213 	} else {
4214 		/* The intention is that in future we will
4215 		 * assume that full constraints are provided
4216 		 * so warn even if we aren't going to do
4217 		 * anything here.
4218 		 */
4219 		rdev_warn(rdev, "incomplete constraints, leaving on\n");
4220 	}
4221 
4222 unlock:
4223 	mutex_unlock(&rdev->mutex);
4224 
4225 	return 0;
4226 }
4227 
4228 static int __init regulator_init_complete(void)
4229 {
4230 	/*
4231 	 * Since DT doesn't provide an idiomatic mechanism for
4232 	 * enabling full constraints and since it's much more natural
4233 	 * with DT to provide them just assume that a DT enabled
4234 	 * system has full constraints.
4235 	 */
4236 	if (of_have_populated_dt())
4237 		has_full_constraints = true;
4238 
4239 	/* If we have a full configuration then disable any regulators
4240 	 * we have permission to change the status for and which are
4241 	 * not in use or always_on.  This is effectively the default
4242 	 * for DT and ACPI as they have full constraints.
4243 	 */
4244 	class_for_each_device(&regulator_class, NULL, NULL,
4245 			      regulator_late_cleanup);
4246 
4247 	return 0;
4248 }
4249 late_initcall_sync(regulator_init_complete);
4250