xref: /linux/drivers/regulator/core.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
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 		/* Did the lookup explicitly defer for us? */
1407 		if (ret == -EPROBE_DEFER)
1408 			return ret;
1409 
1410 		if (have_full_constraints()) {
1411 			r = dummy_regulator_rdev;
1412 		} else {
1413 			dev_err(dev, "Failed to resolve %s-supply for %s\n",
1414 				rdev->supply_name, rdev->desc->name);
1415 			return -EPROBE_DEFER;
1416 		}
1417 	}
1418 
1419 	/* Recursively resolve the supply of the supply */
1420 	ret = regulator_resolve_supply(r);
1421 	if (ret < 0)
1422 		return ret;
1423 
1424 	ret = set_supply(rdev, r);
1425 	if (ret < 0)
1426 		return ret;
1427 
1428 	/* Cascade always-on state to supply */
1429 	if (_regulator_is_enabled(rdev) && rdev->supply) {
1430 		ret = regulator_enable(rdev->supply);
1431 		if (ret < 0) {
1432 			_regulator_put(rdev->supply);
1433 			return ret;
1434 		}
1435 	}
1436 
1437 	return 0;
1438 }
1439 
1440 /* Internal regulator request function */
1441 static struct regulator *_regulator_get(struct device *dev, const char *id,
1442 					bool exclusive, bool allow_dummy)
1443 {
1444 	struct regulator_dev *rdev;
1445 	struct regulator *regulator = ERR_PTR(-EPROBE_DEFER);
1446 	const char *devname = NULL;
1447 	int ret;
1448 
1449 	if (id == NULL) {
1450 		pr_err("get() with no identifier\n");
1451 		return ERR_PTR(-EINVAL);
1452 	}
1453 
1454 	if (dev)
1455 		devname = dev_name(dev);
1456 
1457 	if (have_full_constraints())
1458 		ret = -ENODEV;
1459 	else
1460 		ret = -EPROBE_DEFER;
1461 
1462 	mutex_lock(&regulator_list_mutex);
1463 
1464 	rdev = regulator_dev_lookup(dev, id, &ret);
1465 	if (rdev)
1466 		goto found;
1467 
1468 	regulator = ERR_PTR(ret);
1469 
1470 	/*
1471 	 * If we have return value from dev_lookup fail, we do not expect to
1472 	 * succeed, so, quit with appropriate error value
1473 	 */
1474 	if (ret && ret != -ENODEV)
1475 		goto out;
1476 
1477 	if (!devname)
1478 		devname = "deviceless";
1479 
1480 	/*
1481 	 * Assume that a regulator is physically present and enabled
1482 	 * even if it isn't hooked up and just provide a dummy.
1483 	 */
1484 	if (have_full_constraints() && allow_dummy) {
1485 		pr_warn("%s supply %s not found, using dummy regulator\n",
1486 			devname, id);
1487 
1488 		rdev = dummy_regulator_rdev;
1489 		goto found;
1490 	/* Don't log an error when called from regulator_get_optional() */
1491 	} else if (!have_full_constraints() || exclusive) {
1492 		dev_warn(dev, "dummy supplies not allowed\n");
1493 	}
1494 
1495 	mutex_unlock(&regulator_list_mutex);
1496 	return regulator;
1497 
1498 found:
1499 	if (rdev->exclusive) {
1500 		regulator = ERR_PTR(-EPERM);
1501 		goto out;
1502 	}
1503 
1504 	if (exclusive && rdev->open_count) {
1505 		regulator = ERR_PTR(-EBUSY);
1506 		goto out;
1507 	}
1508 
1509 	ret = regulator_resolve_supply(rdev);
1510 	if (ret < 0) {
1511 		regulator = ERR_PTR(ret);
1512 		goto out;
1513 	}
1514 
1515 	if (!try_module_get(rdev->owner))
1516 		goto out;
1517 
1518 	regulator = create_regulator(rdev, dev, id);
1519 	if (regulator == NULL) {
1520 		regulator = ERR_PTR(-ENOMEM);
1521 		module_put(rdev->owner);
1522 		goto out;
1523 	}
1524 
1525 	rdev->open_count++;
1526 	if (exclusive) {
1527 		rdev->exclusive = 1;
1528 
1529 		ret = _regulator_is_enabled(rdev);
1530 		if (ret > 0)
1531 			rdev->use_count = 1;
1532 		else
1533 			rdev->use_count = 0;
1534 	}
1535 
1536 out:
1537 	mutex_unlock(&regulator_list_mutex);
1538 
1539 	return regulator;
1540 }
1541 
1542 /**
1543  * regulator_get - lookup and obtain a reference to a regulator.
1544  * @dev: device for regulator "consumer"
1545  * @id: Supply name or regulator ID.
1546  *
1547  * Returns a struct regulator corresponding to the regulator producer,
1548  * or IS_ERR() condition containing errno.
1549  *
1550  * Use of supply names configured via regulator_set_device_supply() is
1551  * strongly encouraged.  It is recommended that the supply name used
1552  * should match the name used for the supply and/or the relevant
1553  * device pins in the datasheet.
1554  */
1555 struct regulator *regulator_get(struct device *dev, const char *id)
1556 {
1557 	return _regulator_get(dev, id, false, true);
1558 }
1559 EXPORT_SYMBOL_GPL(regulator_get);
1560 
1561 /**
1562  * regulator_get_exclusive - obtain exclusive access to a regulator.
1563  * @dev: device for regulator "consumer"
1564  * @id: Supply name or regulator ID.
1565  *
1566  * Returns a struct regulator corresponding to the regulator producer,
1567  * or IS_ERR() condition containing errno.  Other consumers will be
1568  * unable to obtain this regulator while this reference is held and the
1569  * use count for the regulator will be initialised to reflect the current
1570  * state of the regulator.
1571  *
1572  * This is intended for use by consumers which cannot tolerate shared
1573  * use of the regulator such as those which need to force the
1574  * regulator off for correct operation of the hardware they are
1575  * controlling.
1576  *
1577  * Use of supply names configured via regulator_set_device_supply() is
1578  * strongly encouraged.  It is recommended that the supply name used
1579  * should match the name used for the supply and/or the relevant
1580  * device pins in the datasheet.
1581  */
1582 struct regulator *regulator_get_exclusive(struct device *dev, const char *id)
1583 {
1584 	return _regulator_get(dev, id, true, false);
1585 }
1586 EXPORT_SYMBOL_GPL(regulator_get_exclusive);
1587 
1588 /**
1589  * regulator_get_optional - obtain optional access to a regulator.
1590  * @dev: device for regulator "consumer"
1591  * @id: Supply name or regulator ID.
1592  *
1593  * Returns a struct regulator corresponding to the regulator producer,
1594  * or IS_ERR() condition containing errno.
1595  *
1596  * This is intended for use by consumers for devices which can have
1597  * some supplies unconnected in normal use, such as some MMC devices.
1598  * It can allow the regulator core to provide stub supplies for other
1599  * supplies requested using normal regulator_get() calls without
1600  * disrupting the operation of drivers that can handle absent
1601  * supplies.
1602  *
1603  * Use of supply names configured via regulator_set_device_supply() is
1604  * strongly encouraged.  It is recommended that the supply name used
1605  * should match the name used for the supply and/or the relevant
1606  * device pins in the datasheet.
1607  */
1608 struct regulator *regulator_get_optional(struct device *dev, const char *id)
1609 {
1610 	return _regulator_get(dev, id, false, false);
1611 }
1612 EXPORT_SYMBOL_GPL(regulator_get_optional);
1613 
1614 /* regulator_list_mutex lock held by regulator_put() */
1615 static void _regulator_put(struct regulator *regulator)
1616 {
1617 	struct regulator_dev *rdev;
1618 
1619 	if (IS_ERR_OR_NULL(regulator))
1620 		return;
1621 
1622 	lockdep_assert_held_once(&regulator_list_mutex);
1623 
1624 	rdev = regulator->rdev;
1625 
1626 	debugfs_remove_recursive(regulator->debugfs);
1627 
1628 	/* remove any sysfs entries */
1629 	if (regulator->dev)
1630 		sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
1631 	mutex_lock(&rdev->mutex);
1632 	list_del(&regulator->list);
1633 
1634 	rdev->open_count--;
1635 	rdev->exclusive = 0;
1636 	mutex_unlock(&rdev->mutex);
1637 
1638 	kfree(regulator->supply_name);
1639 	kfree(regulator);
1640 
1641 	module_put(rdev->owner);
1642 }
1643 
1644 /**
1645  * regulator_put - "free" the regulator source
1646  * @regulator: regulator source
1647  *
1648  * Note: drivers must ensure that all regulator_enable calls made on this
1649  * regulator source are balanced by regulator_disable calls prior to calling
1650  * this function.
1651  */
1652 void regulator_put(struct regulator *regulator)
1653 {
1654 	mutex_lock(&regulator_list_mutex);
1655 	_regulator_put(regulator);
1656 	mutex_unlock(&regulator_list_mutex);
1657 }
1658 EXPORT_SYMBOL_GPL(regulator_put);
1659 
1660 /**
1661  * regulator_register_supply_alias - Provide device alias for supply lookup
1662  *
1663  * @dev: device that will be given as the regulator "consumer"
1664  * @id: Supply name or regulator ID
1665  * @alias_dev: device that should be used to lookup the supply
1666  * @alias_id: Supply name or regulator ID that should be used to lookup the
1667  * supply
1668  *
1669  * All lookups for id on dev will instead be conducted for alias_id on
1670  * alias_dev.
1671  */
1672 int regulator_register_supply_alias(struct device *dev, const char *id,
1673 				    struct device *alias_dev,
1674 				    const char *alias_id)
1675 {
1676 	struct regulator_supply_alias *map;
1677 
1678 	map = regulator_find_supply_alias(dev, id);
1679 	if (map)
1680 		return -EEXIST;
1681 
1682 	map = kzalloc(sizeof(struct regulator_supply_alias), GFP_KERNEL);
1683 	if (!map)
1684 		return -ENOMEM;
1685 
1686 	map->src_dev = dev;
1687 	map->src_supply = id;
1688 	map->alias_dev = alias_dev;
1689 	map->alias_supply = alias_id;
1690 
1691 	list_add(&map->list, &regulator_supply_alias_list);
1692 
1693 	pr_info("Adding alias for supply %s,%s -> %s,%s\n",
1694 		id, dev_name(dev), alias_id, dev_name(alias_dev));
1695 
1696 	return 0;
1697 }
1698 EXPORT_SYMBOL_GPL(regulator_register_supply_alias);
1699 
1700 /**
1701  * regulator_unregister_supply_alias - Remove device alias
1702  *
1703  * @dev: device that will be given as the regulator "consumer"
1704  * @id: Supply name or regulator ID
1705  *
1706  * Remove a lookup alias if one exists for id on dev.
1707  */
1708 void regulator_unregister_supply_alias(struct device *dev, const char *id)
1709 {
1710 	struct regulator_supply_alias *map;
1711 
1712 	map = regulator_find_supply_alias(dev, id);
1713 	if (map) {
1714 		list_del(&map->list);
1715 		kfree(map);
1716 	}
1717 }
1718 EXPORT_SYMBOL_GPL(regulator_unregister_supply_alias);
1719 
1720 /**
1721  * regulator_bulk_register_supply_alias - register multiple aliases
1722  *
1723  * @dev: device that will be given as the regulator "consumer"
1724  * @id: List of supply names or regulator IDs
1725  * @alias_dev: device that should be used to lookup the supply
1726  * @alias_id: List of supply names or regulator IDs that should be used to
1727  * lookup the supply
1728  * @num_id: Number of aliases to register
1729  *
1730  * @return 0 on success, an errno on failure.
1731  *
1732  * This helper function allows drivers to register several supply
1733  * aliases in one operation.  If any of the aliases cannot be
1734  * registered any aliases that were registered will be removed
1735  * before returning to the caller.
1736  */
1737 int regulator_bulk_register_supply_alias(struct device *dev,
1738 					 const char *const *id,
1739 					 struct device *alias_dev,
1740 					 const char *const *alias_id,
1741 					 int num_id)
1742 {
1743 	int i;
1744 	int ret;
1745 
1746 	for (i = 0; i < num_id; ++i) {
1747 		ret = regulator_register_supply_alias(dev, id[i], alias_dev,
1748 						      alias_id[i]);
1749 		if (ret < 0)
1750 			goto err;
1751 	}
1752 
1753 	return 0;
1754 
1755 err:
1756 	dev_err(dev,
1757 		"Failed to create supply alias %s,%s -> %s,%s\n",
1758 		id[i], dev_name(dev), alias_id[i], dev_name(alias_dev));
1759 
1760 	while (--i >= 0)
1761 		regulator_unregister_supply_alias(dev, id[i]);
1762 
1763 	return ret;
1764 }
1765 EXPORT_SYMBOL_GPL(regulator_bulk_register_supply_alias);
1766 
1767 /**
1768  * regulator_bulk_unregister_supply_alias - unregister multiple aliases
1769  *
1770  * @dev: device that will be given as the regulator "consumer"
1771  * @id: List of supply names or regulator IDs
1772  * @num_id: Number of aliases to unregister
1773  *
1774  * This helper function allows drivers to unregister several supply
1775  * aliases in one operation.
1776  */
1777 void regulator_bulk_unregister_supply_alias(struct device *dev,
1778 					    const char *const *id,
1779 					    int num_id)
1780 {
1781 	int i;
1782 
1783 	for (i = 0; i < num_id; ++i)
1784 		regulator_unregister_supply_alias(dev, id[i]);
1785 }
1786 EXPORT_SYMBOL_GPL(regulator_bulk_unregister_supply_alias);
1787 
1788 
1789 /* Manage enable GPIO list. Same GPIO pin can be shared among regulators */
1790 static int regulator_ena_gpio_request(struct regulator_dev *rdev,
1791 				const struct regulator_config *config)
1792 {
1793 	struct regulator_enable_gpio *pin;
1794 	struct gpio_desc *gpiod;
1795 	int ret;
1796 
1797 	gpiod = gpio_to_desc(config->ena_gpio);
1798 
1799 	list_for_each_entry(pin, &regulator_ena_gpio_list, list) {
1800 		if (pin->gpiod == gpiod) {
1801 			rdev_dbg(rdev, "GPIO %d is already used\n",
1802 				config->ena_gpio);
1803 			goto update_ena_gpio_to_rdev;
1804 		}
1805 	}
1806 
1807 	ret = gpio_request_one(config->ena_gpio,
1808 				GPIOF_DIR_OUT | config->ena_gpio_flags,
1809 				rdev_get_name(rdev));
1810 	if (ret)
1811 		return ret;
1812 
1813 	pin = kzalloc(sizeof(struct regulator_enable_gpio), GFP_KERNEL);
1814 	if (pin == NULL) {
1815 		gpio_free(config->ena_gpio);
1816 		return -ENOMEM;
1817 	}
1818 
1819 	pin->gpiod = gpiod;
1820 	pin->ena_gpio_invert = config->ena_gpio_invert;
1821 	list_add(&pin->list, &regulator_ena_gpio_list);
1822 
1823 update_ena_gpio_to_rdev:
1824 	pin->request_count++;
1825 	rdev->ena_pin = pin;
1826 	return 0;
1827 }
1828 
1829 static void regulator_ena_gpio_free(struct regulator_dev *rdev)
1830 {
1831 	struct regulator_enable_gpio *pin, *n;
1832 
1833 	if (!rdev->ena_pin)
1834 		return;
1835 
1836 	/* Free the GPIO only in case of no use */
1837 	list_for_each_entry_safe(pin, n, &regulator_ena_gpio_list, list) {
1838 		if (pin->gpiod == rdev->ena_pin->gpiod) {
1839 			if (pin->request_count <= 1) {
1840 				pin->request_count = 0;
1841 				gpiod_put(pin->gpiod);
1842 				list_del(&pin->list);
1843 				kfree(pin);
1844 				rdev->ena_pin = NULL;
1845 				return;
1846 			} else {
1847 				pin->request_count--;
1848 			}
1849 		}
1850 	}
1851 }
1852 
1853 /**
1854  * regulator_ena_gpio_ctrl - balance enable_count of each GPIO and actual GPIO pin control
1855  * @rdev: regulator_dev structure
1856  * @enable: enable GPIO at initial use?
1857  *
1858  * GPIO is enabled in case of initial use. (enable_count is 0)
1859  * GPIO is disabled when it is not shared any more. (enable_count <= 1)
1860  */
1861 static int regulator_ena_gpio_ctrl(struct regulator_dev *rdev, bool enable)
1862 {
1863 	struct regulator_enable_gpio *pin = rdev->ena_pin;
1864 
1865 	if (!pin)
1866 		return -EINVAL;
1867 
1868 	if (enable) {
1869 		/* Enable GPIO at initial use */
1870 		if (pin->enable_count == 0)
1871 			gpiod_set_value_cansleep(pin->gpiod,
1872 						 !pin->ena_gpio_invert);
1873 
1874 		pin->enable_count++;
1875 	} else {
1876 		if (pin->enable_count > 1) {
1877 			pin->enable_count--;
1878 			return 0;
1879 		}
1880 
1881 		/* Disable GPIO if not used */
1882 		if (pin->enable_count <= 1) {
1883 			gpiod_set_value_cansleep(pin->gpiod,
1884 						 pin->ena_gpio_invert);
1885 			pin->enable_count = 0;
1886 		}
1887 	}
1888 
1889 	return 0;
1890 }
1891 
1892 /**
1893  * _regulator_enable_delay - a delay helper function
1894  * @delay: time to delay in microseconds
1895  *
1896  * Delay for the requested amount of time as per the guidelines in:
1897  *
1898  *     Documentation/timers/timers-howto.txt
1899  *
1900  * The assumption here is that regulators will never be enabled in
1901  * atomic context and therefore sleeping functions can be used.
1902  */
1903 static void _regulator_enable_delay(unsigned int delay)
1904 {
1905 	unsigned int ms = delay / 1000;
1906 	unsigned int us = delay % 1000;
1907 
1908 	if (ms > 0) {
1909 		/*
1910 		 * For small enough values, handle super-millisecond
1911 		 * delays in the usleep_range() call below.
1912 		 */
1913 		if (ms < 20)
1914 			us += ms * 1000;
1915 		else
1916 			msleep(ms);
1917 	}
1918 
1919 	/*
1920 	 * Give the scheduler some room to coalesce with any other
1921 	 * wakeup sources. For delays shorter than 10 us, don't even
1922 	 * bother setting up high-resolution timers and just busy-
1923 	 * loop.
1924 	 */
1925 	if (us >= 10)
1926 		usleep_range(us, us + 100);
1927 	else
1928 		udelay(us);
1929 }
1930 
1931 static int _regulator_do_enable(struct regulator_dev *rdev)
1932 {
1933 	int ret, delay;
1934 
1935 	/* Query before enabling in case configuration dependent.  */
1936 	ret = _regulator_get_enable_time(rdev);
1937 	if (ret >= 0) {
1938 		delay = ret;
1939 	} else {
1940 		rdev_warn(rdev, "enable_time() failed: %d\n", ret);
1941 		delay = 0;
1942 	}
1943 
1944 	trace_regulator_enable(rdev_get_name(rdev));
1945 
1946 	if (rdev->desc->off_on_delay) {
1947 		/* if needed, keep a distance of off_on_delay from last time
1948 		 * this regulator was disabled.
1949 		 */
1950 		unsigned long start_jiffy = jiffies;
1951 		unsigned long intended, max_delay, remaining;
1952 
1953 		max_delay = usecs_to_jiffies(rdev->desc->off_on_delay);
1954 		intended = rdev->last_off_jiffy + max_delay;
1955 
1956 		if (time_before(start_jiffy, intended)) {
1957 			/* calc remaining jiffies to deal with one-time
1958 			 * timer wrapping.
1959 			 * in case of multiple timer wrapping, either it can be
1960 			 * detected by out-of-range remaining, or it cannot be
1961 			 * detected and we gets a panelty of
1962 			 * _regulator_enable_delay().
1963 			 */
1964 			remaining = intended - start_jiffy;
1965 			if (remaining <= max_delay)
1966 				_regulator_enable_delay(
1967 						jiffies_to_usecs(remaining));
1968 		}
1969 	}
1970 
1971 	if (rdev->ena_pin) {
1972 		if (!rdev->ena_gpio_state) {
1973 			ret = regulator_ena_gpio_ctrl(rdev, true);
1974 			if (ret < 0)
1975 				return ret;
1976 			rdev->ena_gpio_state = 1;
1977 		}
1978 	} else if (rdev->desc->ops->enable) {
1979 		ret = rdev->desc->ops->enable(rdev);
1980 		if (ret < 0)
1981 			return ret;
1982 	} else {
1983 		return -EINVAL;
1984 	}
1985 
1986 	/* Allow the regulator to ramp; it would be useful to extend
1987 	 * this for bulk operations so that the regulators can ramp
1988 	 * together.  */
1989 	trace_regulator_enable_delay(rdev_get_name(rdev));
1990 
1991 	_regulator_enable_delay(delay);
1992 
1993 	trace_regulator_enable_complete(rdev_get_name(rdev));
1994 
1995 	return 0;
1996 }
1997 
1998 /* locks held by regulator_enable() */
1999 static int _regulator_enable(struct regulator_dev *rdev)
2000 {
2001 	int ret;
2002 
2003 	lockdep_assert_held_once(&rdev->mutex);
2004 
2005 	/* check voltage and requested load before enabling */
2006 	if (rdev->constraints &&
2007 	    (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS))
2008 		drms_uA_update(rdev);
2009 
2010 	if (rdev->use_count == 0) {
2011 		/* The regulator may on if it's not switchable or left on */
2012 		ret = _regulator_is_enabled(rdev);
2013 		if (ret == -EINVAL || ret == 0) {
2014 			if (!_regulator_can_change_status(rdev))
2015 				return -EPERM;
2016 
2017 			ret = _regulator_do_enable(rdev);
2018 			if (ret < 0)
2019 				return ret;
2020 
2021 		} else if (ret < 0) {
2022 			rdev_err(rdev, "is_enabled() failed: %d\n", ret);
2023 			return ret;
2024 		}
2025 		/* Fallthrough on positive return values - already enabled */
2026 	}
2027 
2028 	rdev->use_count++;
2029 
2030 	return 0;
2031 }
2032 
2033 /**
2034  * regulator_enable - enable regulator output
2035  * @regulator: regulator source
2036  *
2037  * Request that the regulator be enabled with the regulator output at
2038  * the predefined voltage or current value.  Calls to regulator_enable()
2039  * must be balanced with calls to regulator_disable().
2040  *
2041  * NOTE: the output value can be set by other drivers, boot loader or may be
2042  * hardwired in the regulator.
2043  */
2044 int regulator_enable(struct regulator *regulator)
2045 {
2046 	struct regulator_dev *rdev = regulator->rdev;
2047 	int ret = 0;
2048 
2049 	if (regulator->always_on)
2050 		return 0;
2051 
2052 	if (rdev->supply) {
2053 		ret = regulator_enable(rdev->supply);
2054 		if (ret != 0)
2055 			return ret;
2056 	}
2057 
2058 	mutex_lock(&rdev->mutex);
2059 	ret = _regulator_enable(rdev);
2060 	mutex_unlock(&rdev->mutex);
2061 
2062 	if (ret != 0 && rdev->supply)
2063 		regulator_disable(rdev->supply);
2064 
2065 	return ret;
2066 }
2067 EXPORT_SYMBOL_GPL(regulator_enable);
2068 
2069 static int _regulator_do_disable(struct regulator_dev *rdev)
2070 {
2071 	int ret;
2072 
2073 	trace_regulator_disable(rdev_get_name(rdev));
2074 
2075 	if (rdev->ena_pin) {
2076 		if (rdev->ena_gpio_state) {
2077 			ret = regulator_ena_gpio_ctrl(rdev, false);
2078 			if (ret < 0)
2079 				return ret;
2080 			rdev->ena_gpio_state = 0;
2081 		}
2082 
2083 	} else if (rdev->desc->ops->disable) {
2084 		ret = rdev->desc->ops->disable(rdev);
2085 		if (ret != 0)
2086 			return ret;
2087 	}
2088 
2089 	/* cares about last_off_jiffy only if off_on_delay is required by
2090 	 * device.
2091 	 */
2092 	if (rdev->desc->off_on_delay)
2093 		rdev->last_off_jiffy = jiffies;
2094 
2095 	trace_regulator_disable_complete(rdev_get_name(rdev));
2096 
2097 	return 0;
2098 }
2099 
2100 /* locks held by regulator_disable() */
2101 static int _regulator_disable(struct regulator_dev *rdev)
2102 {
2103 	int ret = 0;
2104 
2105 	lockdep_assert_held_once(&rdev->mutex);
2106 
2107 	if (WARN(rdev->use_count <= 0,
2108 		 "unbalanced disables for %s\n", rdev_get_name(rdev)))
2109 		return -EIO;
2110 
2111 	/* are we the last user and permitted to disable ? */
2112 	if (rdev->use_count == 1 &&
2113 	    (rdev->constraints && !rdev->constraints->always_on)) {
2114 
2115 		/* we are last user */
2116 		if (_regulator_can_change_status(rdev)) {
2117 			ret = _notifier_call_chain(rdev,
2118 						   REGULATOR_EVENT_PRE_DISABLE,
2119 						   NULL);
2120 			if (ret & NOTIFY_STOP_MASK)
2121 				return -EINVAL;
2122 
2123 			ret = _regulator_do_disable(rdev);
2124 			if (ret < 0) {
2125 				rdev_err(rdev, "failed to disable\n");
2126 				_notifier_call_chain(rdev,
2127 						REGULATOR_EVENT_ABORT_DISABLE,
2128 						NULL);
2129 				return ret;
2130 			}
2131 			_notifier_call_chain(rdev, REGULATOR_EVENT_DISABLE,
2132 					NULL);
2133 		}
2134 
2135 		rdev->use_count = 0;
2136 	} else if (rdev->use_count > 1) {
2137 
2138 		if (rdev->constraints &&
2139 			(rdev->constraints->valid_ops_mask &
2140 			REGULATOR_CHANGE_DRMS))
2141 			drms_uA_update(rdev);
2142 
2143 		rdev->use_count--;
2144 	}
2145 
2146 	return ret;
2147 }
2148 
2149 /**
2150  * regulator_disable - disable regulator output
2151  * @regulator: regulator source
2152  *
2153  * Disable the regulator output voltage or current.  Calls to
2154  * regulator_enable() must be balanced with calls to
2155  * regulator_disable().
2156  *
2157  * NOTE: this will only disable the regulator output if no other consumer
2158  * devices have it enabled, the regulator device supports disabling and
2159  * machine constraints permit this operation.
2160  */
2161 int regulator_disable(struct regulator *regulator)
2162 {
2163 	struct regulator_dev *rdev = regulator->rdev;
2164 	int ret = 0;
2165 
2166 	if (regulator->always_on)
2167 		return 0;
2168 
2169 	mutex_lock(&rdev->mutex);
2170 	ret = _regulator_disable(rdev);
2171 	mutex_unlock(&rdev->mutex);
2172 
2173 	if (ret == 0 && rdev->supply)
2174 		regulator_disable(rdev->supply);
2175 
2176 	return ret;
2177 }
2178 EXPORT_SYMBOL_GPL(regulator_disable);
2179 
2180 /* locks held by regulator_force_disable() */
2181 static int _regulator_force_disable(struct regulator_dev *rdev)
2182 {
2183 	int ret = 0;
2184 
2185 	lockdep_assert_held_once(&rdev->mutex);
2186 
2187 	ret = _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
2188 			REGULATOR_EVENT_PRE_DISABLE, NULL);
2189 	if (ret & NOTIFY_STOP_MASK)
2190 		return -EINVAL;
2191 
2192 	ret = _regulator_do_disable(rdev);
2193 	if (ret < 0) {
2194 		rdev_err(rdev, "failed to force disable\n");
2195 		_notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
2196 				REGULATOR_EVENT_ABORT_DISABLE, NULL);
2197 		return ret;
2198 	}
2199 
2200 	_notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
2201 			REGULATOR_EVENT_DISABLE, NULL);
2202 
2203 	return 0;
2204 }
2205 
2206 /**
2207  * regulator_force_disable - force disable regulator output
2208  * @regulator: regulator source
2209  *
2210  * Forcibly disable the regulator output voltage or current.
2211  * NOTE: this *will* disable the regulator output even if other consumer
2212  * devices have it enabled. This should be used for situations when device
2213  * damage will likely occur if the regulator is not disabled (e.g. over temp).
2214  */
2215 int regulator_force_disable(struct regulator *regulator)
2216 {
2217 	struct regulator_dev *rdev = regulator->rdev;
2218 	int ret;
2219 
2220 	mutex_lock(&rdev->mutex);
2221 	regulator->uA_load = 0;
2222 	ret = _regulator_force_disable(regulator->rdev);
2223 	mutex_unlock(&rdev->mutex);
2224 
2225 	if (rdev->supply)
2226 		while (rdev->open_count--)
2227 			regulator_disable(rdev->supply);
2228 
2229 	return ret;
2230 }
2231 EXPORT_SYMBOL_GPL(regulator_force_disable);
2232 
2233 static void regulator_disable_work(struct work_struct *work)
2234 {
2235 	struct regulator_dev *rdev = container_of(work, struct regulator_dev,
2236 						  disable_work.work);
2237 	int count, i, ret;
2238 
2239 	mutex_lock(&rdev->mutex);
2240 
2241 	BUG_ON(!rdev->deferred_disables);
2242 
2243 	count = rdev->deferred_disables;
2244 	rdev->deferred_disables = 0;
2245 
2246 	for (i = 0; i < count; i++) {
2247 		ret = _regulator_disable(rdev);
2248 		if (ret != 0)
2249 			rdev_err(rdev, "Deferred disable failed: %d\n", ret);
2250 	}
2251 
2252 	mutex_unlock(&rdev->mutex);
2253 
2254 	if (rdev->supply) {
2255 		for (i = 0; i < count; i++) {
2256 			ret = regulator_disable(rdev->supply);
2257 			if (ret != 0) {
2258 				rdev_err(rdev,
2259 					 "Supply disable failed: %d\n", ret);
2260 			}
2261 		}
2262 	}
2263 }
2264 
2265 /**
2266  * regulator_disable_deferred - disable regulator output with delay
2267  * @regulator: regulator source
2268  * @ms: miliseconds until the regulator is disabled
2269  *
2270  * Execute regulator_disable() on the regulator after a delay.  This
2271  * is intended for use with devices that require some time to quiesce.
2272  *
2273  * NOTE: this will only disable the regulator output if no other consumer
2274  * devices have it enabled, the regulator device supports disabling and
2275  * machine constraints permit this operation.
2276  */
2277 int regulator_disable_deferred(struct regulator *regulator, int ms)
2278 {
2279 	struct regulator_dev *rdev = regulator->rdev;
2280 	int ret;
2281 
2282 	if (regulator->always_on)
2283 		return 0;
2284 
2285 	if (!ms)
2286 		return regulator_disable(regulator);
2287 
2288 	mutex_lock(&rdev->mutex);
2289 	rdev->deferred_disables++;
2290 	mutex_unlock(&rdev->mutex);
2291 
2292 	ret = queue_delayed_work(system_power_efficient_wq,
2293 				 &rdev->disable_work,
2294 				 msecs_to_jiffies(ms));
2295 	if (ret < 0)
2296 		return ret;
2297 	else
2298 		return 0;
2299 }
2300 EXPORT_SYMBOL_GPL(regulator_disable_deferred);
2301 
2302 static int _regulator_is_enabled(struct regulator_dev *rdev)
2303 {
2304 	/* A GPIO control always takes precedence */
2305 	if (rdev->ena_pin)
2306 		return rdev->ena_gpio_state;
2307 
2308 	/* If we don't know then assume that the regulator is always on */
2309 	if (!rdev->desc->ops->is_enabled)
2310 		return 1;
2311 
2312 	return rdev->desc->ops->is_enabled(rdev);
2313 }
2314 
2315 /**
2316  * regulator_is_enabled - is the regulator output enabled
2317  * @regulator: regulator source
2318  *
2319  * Returns positive if the regulator driver backing the source/client
2320  * has requested that the device be enabled, zero if it hasn't, else a
2321  * negative errno code.
2322  *
2323  * Note that the device backing this regulator handle can have multiple
2324  * users, so it might be enabled even if regulator_enable() was never
2325  * called for this particular source.
2326  */
2327 int regulator_is_enabled(struct regulator *regulator)
2328 {
2329 	int ret;
2330 
2331 	if (regulator->always_on)
2332 		return 1;
2333 
2334 	mutex_lock(&regulator->rdev->mutex);
2335 	ret = _regulator_is_enabled(regulator->rdev);
2336 	mutex_unlock(&regulator->rdev->mutex);
2337 
2338 	return ret;
2339 }
2340 EXPORT_SYMBOL_GPL(regulator_is_enabled);
2341 
2342 /**
2343  * regulator_can_change_voltage - check if regulator can change voltage
2344  * @regulator: regulator source
2345  *
2346  * Returns positive if the regulator driver backing the source/client
2347  * can change its voltage, false otherwise. Useful for detecting fixed
2348  * or dummy regulators and disabling voltage change logic in the client
2349  * driver.
2350  */
2351 int regulator_can_change_voltage(struct regulator *regulator)
2352 {
2353 	struct regulator_dev	*rdev = regulator->rdev;
2354 
2355 	if (rdev->constraints &&
2356 	    (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
2357 		if (rdev->desc->n_voltages - rdev->desc->linear_min_sel > 1)
2358 			return 1;
2359 
2360 		if (rdev->desc->continuous_voltage_range &&
2361 		    rdev->constraints->min_uV && rdev->constraints->max_uV &&
2362 		    rdev->constraints->min_uV != rdev->constraints->max_uV)
2363 			return 1;
2364 	}
2365 
2366 	return 0;
2367 }
2368 EXPORT_SYMBOL_GPL(regulator_can_change_voltage);
2369 
2370 /**
2371  * regulator_count_voltages - count regulator_list_voltage() selectors
2372  * @regulator: regulator source
2373  *
2374  * Returns number of selectors, or negative errno.  Selectors are
2375  * numbered starting at zero, and typically correspond to bitfields
2376  * in hardware registers.
2377  */
2378 int regulator_count_voltages(struct regulator *regulator)
2379 {
2380 	struct regulator_dev	*rdev = regulator->rdev;
2381 
2382 	if (rdev->desc->n_voltages)
2383 		return rdev->desc->n_voltages;
2384 
2385 	if (!rdev->supply)
2386 		return -EINVAL;
2387 
2388 	return regulator_count_voltages(rdev->supply);
2389 }
2390 EXPORT_SYMBOL_GPL(regulator_count_voltages);
2391 
2392 /**
2393  * regulator_list_voltage - enumerate supported voltages
2394  * @regulator: regulator source
2395  * @selector: identify voltage to list
2396  * Context: can sleep
2397  *
2398  * Returns a voltage that can be passed to @regulator_set_voltage(),
2399  * zero if this selector code can't be used on this system, or a
2400  * negative errno.
2401  */
2402 int regulator_list_voltage(struct regulator *regulator, unsigned selector)
2403 {
2404 	struct regulator_dev *rdev = regulator->rdev;
2405 	const struct regulator_ops *ops = rdev->desc->ops;
2406 	int ret;
2407 
2408 	if (rdev->desc->fixed_uV && rdev->desc->n_voltages == 1 && !selector)
2409 		return rdev->desc->fixed_uV;
2410 
2411 	if (ops->list_voltage) {
2412 		if (selector >= rdev->desc->n_voltages)
2413 			return -EINVAL;
2414 		mutex_lock(&rdev->mutex);
2415 		ret = ops->list_voltage(rdev, selector);
2416 		mutex_unlock(&rdev->mutex);
2417 	} else if (rdev->supply) {
2418 		ret = regulator_list_voltage(rdev->supply, selector);
2419 	} else {
2420 		return -EINVAL;
2421 	}
2422 
2423 	if (ret > 0) {
2424 		if (ret < rdev->constraints->min_uV)
2425 			ret = 0;
2426 		else if (ret > rdev->constraints->max_uV)
2427 			ret = 0;
2428 	}
2429 
2430 	return ret;
2431 }
2432 EXPORT_SYMBOL_GPL(regulator_list_voltage);
2433 
2434 /**
2435  * regulator_get_regmap - get the regulator's register map
2436  * @regulator: regulator source
2437  *
2438  * Returns the register map for the given regulator, or an ERR_PTR value
2439  * if the regulator doesn't use regmap.
2440  */
2441 struct regmap *regulator_get_regmap(struct regulator *regulator)
2442 {
2443 	struct regmap *map = regulator->rdev->regmap;
2444 
2445 	return map ? map : ERR_PTR(-EOPNOTSUPP);
2446 }
2447 
2448 /**
2449  * regulator_get_hardware_vsel_register - get the HW voltage selector register
2450  * @regulator: regulator source
2451  * @vsel_reg: voltage selector register, output parameter
2452  * @vsel_mask: mask for voltage selector bitfield, output parameter
2453  *
2454  * Returns the hardware register offset and bitmask used for setting the
2455  * regulator voltage. This might be useful when configuring voltage-scaling
2456  * hardware or firmware that can make I2C requests behind the kernel's back,
2457  * for example.
2458  *
2459  * On success, the output parameters @vsel_reg and @vsel_mask are filled in
2460  * and 0 is returned, otherwise a negative errno is returned.
2461  */
2462 int regulator_get_hardware_vsel_register(struct regulator *regulator,
2463 					 unsigned *vsel_reg,
2464 					 unsigned *vsel_mask)
2465 {
2466 	struct regulator_dev *rdev = regulator->rdev;
2467 	const struct regulator_ops *ops = rdev->desc->ops;
2468 
2469 	if (ops->set_voltage_sel != regulator_set_voltage_sel_regmap)
2470 		return -EOPNOTSUPP;
2471 
2472 	 *vsel_reg = rdev->desc->vsel_reg;
2473 	 *vsel_mask = rdev->desc->vsel_mask;
2474 
2475 	 return 0;
2476 }
2477 EXPORT_SYMBOL_GPL(regulator_get_hardware_vsel_register);
2478 
2479 /**
2480  * regulator_list_hardware_vsel - get the HW-specific register value for a selector
2481  * @regulator: regulator source
2482  * @selector: identify voltage to list
2483  *
2484  * Converts the selector to a hardware-specific voltage selector that can be
2485  * directly written to the regulator registers. The address of the voltage
2486  * register can be determined by calling @regulator_get_hardware_vsel_register.
2487  *
2488  * On error a negative errno is returned.
2489  */
2490 int regulator_list_hardware_vsel(struct regulator *regulator,
2491 				 unsigned selector)
2492 {
2493 	struct regulator_dev *rdev = regulator->rdev;
2494 	const struct regulator_ops *ops = rdev->desc->ops;
2495 
2496 	if (selector >= rdev->desc->n_voltages)
2497 		return -EINVAL;
2498 	if (ops->set_voltage_sel != regulator_set_voltage_sel_regmap)
2499 		return -EOPNOTSUPP;
2500 
2501 	return selector;
2502 }
2503 EXPORT_SYMBOL_GPL(regulator_list_hardware_vsel);
2504 
2505 /**
2506  * regulator_get_linear_step - return the voltage step size between VSEL values
2507  * @regulator: regulator source
2508  *
2509  * Returns the voltage step size between VSEL values for linear
2510  * regulators, or return 0 if the regulator isn't a linear regulator.
2511  */
2512 unsigned int regulator_get_linear_step(struct regulator *regulator)
2513 {
2514 	struct regulator_dev *rdev = regulator->rdev;
2515 
2516 	return rdev->desc->uV_step;
2517 }
2518 EXPORT_SYMBOL_GPL(regulator_get_linear_step);
2519 
2520 /**
2521  * regulator_is_supported_voltage - check if a voltage range can be supported
2522  *
2523  * @regulator: Regulator to check.
2524  * @min_uV: Minimum required voltage in uV.
2525  * @max_uV: Maximum required voltage in uV.
2526  *
2527  * Returns a boolean or a negative error code.
2528  */
2529 int regulator_is_supported_voltage(struct regulator *regulator,
2530 				   int min_uV, int max_uV)
2531 {
2532 	struct regulator_dev *rdev = regulator->rdev;
2533 	int i, voltages, ret;
2534 
2535 	/* If we can't change voltage check the current voltage */
2536 	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
2537 		ret = regulator_get_voltage(regulator);
2538 		if (ret >= 0)
2539 			return min_uV <= ret && ret <= max_uV;
2540 		else
2541 			return ret;
2542 	}
2543 
2544 	/* Any voltage within constrains range is fine? */
2545 	if (rdev->desc->continuous_voltage_range)
2546 		return min_uV >= rdev->constraints->min_uV &&
2547 				max_uV <= rdev->constraints->max_uV;
2548 
2549 	ret = regulator_count_voltages(regulator);
2550 	if (ret < 0)
2551 		return ret;
2552 	voltages = ret;
2553 
2554 	for (i = 0; i < voltages; i++) {
2555 		ret = regulator_list_voltage(regulator, i);
2556 
2557 		if (ret >= min_uV && ret <= max_uV)
2558 			return 1;
2559 	}
2560 
2561 	return 0;
2562 }
2563 EXPORT_SYMBOL_GPL(regulator_is_supported_voltage);
2564 
2565 static int _regulator_call_set_voltage(struct regulator_dev *rdev,
2566 				       int min_uV, int max_uV,
2567 				       unsigned *selector)
2568 {
2569 	struct pre_voltage_change_data data;
2570 	int ret;
2571 
2572 	data.old_uV = _regulator_get_voltage(rdev);
2573 	data.min_uV = min_uV;
2574 	data.max_uV = max_uV;
2575 	ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE,
2576 				   &data);
2577 	if (ret & NOTIFY_STOP_MASK)
2578 		return -EINVAL;
2579 
2580 	ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV, selector);
2581 	if (ret >= 0)
2582 		return ret;
2583 
2584 	_notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE,
2585 			     (void *)data.old_uV);
2586 
2587 	return ret;
2588 }
2589 
2590 static int _regulator_call_set_voltage_sel(struct regulator_dev *rdev,
2591 					   int uV, unsigned selector)
2592 {
2593 	struct pre_voltage_change_data data;
2594 	int ret;
2595 
2596 	data.old_uV = _regulator_get_voltage(rdev);
2597 	data.min_uV = uV;
2598 	data.max_uV = uV;
2599 	ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE,
2600 				   &data);
2601 	if (ret & NOTIFY_STOP_MASK)
2602 		return -EINVAL;
2603 
2604 	ret = rdev->desc->ops->set_voltage_sel(rdev, selector);
2605 	if (ret >= 0)
2606 		return ret;
2607 
2608 	_notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE,
2609 			     (void *)data.old_uV);
2610 
2611 	return ret;
2612 }
2613 
2614 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
2615 				     int min_uV, int max_uV)
2616 {
2617 	int ret;
2618 	int delay = 0;
2619 	int best_val = 0;
2620 	unsigned int selector;
2621 	int old_selector = -1;
2622 
2623 	trace_regulator_set_voltage(rdev_get_name(rdev), min_uV, max_uV);
2624 
2625 	min_uV += rdev->constraints->uV_offset;
2626 	max_uV += rdev->constraints->uV_offset;
2627 
2628 	/*
2629 	 * If we can't obtain the old selector there is not enough
2630 	 * info to call set_voltage_time_sel().
2631 	 */
2632 	if (_regulator_is_enabled(rdev) &&
2633 	    rdev->desc->ops->set_voltage_time_sel &&
2634 	    rdev->desc->ops->get_voltage_sel) {
2635 		old_selector = rdev->desc->ops->get_voltage_sel(rdev);
2636 		if (old_selector < 0)
2637 			return old_selector;
2638 	}
2639 
2640 	if (rdev->desc->ops->set_voltage) {
2641 		ret = _regulator_call_set_voltage(rdev, min_uV, max_uV,
2642 						  &selector);
2643 
2644 		if (ret >= 0) {
2645 			if (rdev->desc->ops->list_voltage)
2646 				best_val = rdev->desc->ops->list_voltage(rdev,
2647 									 selector);
2648 			else
2649 				best_val = _regulator_get_voltage(rdev);
2650 		}
2651 
2652 	} else if (rdev->desc->ops->set_voltage_sel) {
2653 		if (rdev->desc->ops->map_voltage) {
2654 			ret = rdev->desc->ops->map_voltage(rdev, min_uV,
2655 							   max_uV);
2656 		} else {
2657 			if (rdev->desc->ops->list_voltage ==
2658 			    regulator_list_voltage_linear)
2659 				ret = regulator_map_voltage_linear(rdev,
2660 								min_uV, max_uV);
2661 			else if (rdev->desc->ops->list_voltage ==
2662 				 regulator_list_voltage_linear_range)
2663 				ret = regulator_map_voltage_linear_range(rdev,
2664 								min_uV, max_uV);
2665 			else
2666 				ret = regulator_map_voltage_iterate(rdev,
2667 								min_uV, max_uV);
2668 		}
2669 
2670 		if (ret >= 0) {
2671 			best_val = rdev->desc->ops->list_voltage(rdev, ret);
2672 			if (min_uV <= best_val && max_uV >= best_val) {
2673 				selector = ret;
2674 				if (old_selector == selector)
2675 					ret = 0;
2676 				else
2677 					ret = _regulator_call_set_voltage_sel(
2678 						rdev, best_val, selector);
2679 			} else {
2680 				ret = -EINVAL;
2681 			}
2682 		}
2683 	} else {
2684 		ret = -EINVAL;
2685 	}
2686 
2687 	/* Call set_voltage_time_sel if successfully obtained old_selector */
2688 	if (ret == 0 && !rdev->constraints->ramp_disable && old_selector >= 0
2689 		&& old_selector != selector) {
2690 
2691 		delay = rdev->desc->ops->set_voltage_time_sel(rdev,
2692 						old_selector, selector);
2693 		if (delay < 0) {
2694 			rdev_warn(rdev, "set_voltage_time_sel() failed: %d\n",
2695 				  delay);
2696 			delay = 0;
2697 		}
2698 
2699 		/* Insert any necessary delays */
2700 		if (delay >= 1000) {
2701 			mdelay(delay / 1000);
2702 			udelay(delay % 1000);
2703 		} else if (delay) {
2704 			udelay(delay);
2705 		}
2706 	}
2707 
2708 	if (ret == 0 && best_val >= 0) {
2709 		unsigned long data = best_val;
2710 
2711 		_notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE,
2712 				     (void *)data);
2713 	}
2714 
2715 	trace_regulator_set_voltage_complete(rdev_get_name(rdev), best_val);
2716 
2717 	return ret;
2718 }
2719 
2720 /**
2721  * regulator_set_voltage - set regulator output voltage
2722  * @regulator: regulator source
2723  * @min_uV: Minimum required voltage in uV
2724  * @max_uV: Maximum acceptable voltage in uV
2725  *
2726  * Sets a voltage regulator to the desired output voltage. This can be set
2727  * during any regulator state. IOW, regulator can be disabled or enabled.
2728  *
2729  * If the regulator is enabled then the voltage will change to the new value
2730  * immediately otherwise if the regulator is disabled the regulator will
2731  * output at the new voltage when enabled.
2732  *
2733  * NOTE: If the regulator is shared between several devices then the lowest
2734  * request voltage that meets the system constraints will be used.
2735  * Regulator system constraints must be set for this regulator before
2736  * calling this function otherwise this call will fail.
2737  */
2738 int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
2739 {
2740 	struct regulator_dev *rdev = regulator->rdev;
2741 	int ret = 0;
2742 	int old_min_uV, old_max_uV;
2743 	int current_uV;
2744 
2745 	mutex_lock(&rdev->mutex);
2746 
2747 	/* If we're setting the same range as last time the change
2748 	 * should be a noop (some cpufreq implementations use the same
2749 	 * voltage for multiple frequencies, for example).
2750 	 */
2751 	if (regulator->min_uV == min_uV && regulator->max_uV == max_uV)
2752 		goto out;
2753 
2754 	/* If we're trying to set a range that overlaps the current voltage,
2755 	 * return successfully even though the regulator does not support
2756 	 * changing the voltage.
2757 	 */
2758 	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
2759 		current_uV = _regulator_get_voltage(rdev);
2760 		if (min_uV <= current_uV && current_uV <= max_uV) {
2761 			regulator->min_uV = min_uV;
2762 			regulator->max_uV = max_uV;
2763 			goto out;
2764 		}
2765 	}
2766 
2767 	/* sanity check */
2768 	if (!rdev->desc->ops->set_voltage &&
2769 	    !rdev->desc->ops->set_voltage_sel) {
2770 		ret = -EINVAL;
2771 		goto out;
2772 	}
2773 
2774 	/* constraints check */
2775 	ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
2776 	if (ret < 0)
2777 		goto out;
2778 
2779 	/* restore original values in case of error */
2780 	old_min_uV = regulator->min_uV;
2781 	old_max_uV = regulator->max_uV;
2782 	regulator->min_uV = min_uV;
2783 	regulator->max_uV = max_uV;
2784 
2785 	ret = regulator_check_consumers(rdev, &min_uV, &max_uV);
2786 	if (ret < 0)
2787 		goto out2;
2788 
2789 	ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
2790 	if (ret < 0)
2791 		goto out2;
2792 
2793 out:
2794 	mutex_unlock(&rdev->mutex);
2795 	return ret;
2796 out2:
2797 	regulator->min_uV = old_min_uV;
2798 	regulator->max_uV = old_max_uV;
2799 	mutex_unlock(&rdev->mutex);
2800 	return ret;
2801 }
2802 EXPORT_SYMBOL_GPL(regulator_set_voltage);
2803 
2804 /**
2805  * regulator_set_voltage_time - get raise/fall time
2806  * @regulator: regulator source
2807  * @old_uV: starting voltage in microvolts
2808  * @new_uV: target voltage in microvolts
2809  *
2810  * Provided with the starting and ending voltage, this function attempts to
2811  * calculate the time in microseconds required to rise or fall to this new
2812  * voltage.
2813  */
2814 int regulator_set_voltage_time(struct regulator *regulator,
2815 			       int old_uV, int new_uV)
2816 {
2817 	struct regulator_dev *rdev = regulator->rdev;
2818 	const struct regulator_ops *ops = rdev->desc->ops;
2819 	int old_sel = -1;
2820 	int new_sel = -1;
2821 	int voltage;
2822 	int i;
2823 
2824 	/* Currently requires operations to do this */
2825 	if (!ops->list_voltage || !ops->set_voltage_time_sel
2826 	    || !rdev->desc->n_voltages)
2827 		return -EINVAL;
2828 
2829 	for (i = 0; i < rdev->desc->n_voltages; i++) {
2830 		/* We only look for exact voltage matches here */
2831 		voltage = regulator_list_voltage(regulator, i);
2832 		if (voltage < 0)
2833 			return -EINVAL;
2834 		if (voltage == 0)
2835 			continue;
2836 		if (voltage == old_uV)
2837 			old_sel = i;
2838 		if (voltage == new_uV)
2839 			new_sel = i;
2840 	}
2841 
2842 	if (old_sel < 0 || new_sel < 0)
2843 		return -EINVAL;
2844 
2845 	return ops->set_voltage_time_sel(rdev, old_sel, new_sel);
2846 }
2847 EXPORT_SYMBOL_GPL(regulator_set_voltage_time);
2848 
2849 /**
2850  * regulator_set_voltage_time_sel - get raise/fall time
2851  * @rdev: regulator source device
2852  * @old_selector: selector for starting voltage
2853  * @new_selector: selector for target voltage
2854  *
2855  * Provided with the starting and target voltage selectors, this function
2856  * returns time in microseconds required to rise or fall to this new voltage
2857  *
2858  * Drivers providing ramp_delay in regulation_constraints can use this as their
2859  * set_voltage_time_sel() operation.
2860  */
2861 int regulator_set_voltage_time_sel(struct regulator_dev *rdev,
2862 				   unsigned int old_selector,
2863 				   unsigned int new_selector)
2864 {
2865 	unsigned int ramp_delay = 0;
2866 	int old_volt, new_volt;
2867 
2868 	if (rdev->constraints->ramp_delay)
2869 		ramp_delay = rdev->constraints->ramp_delay;
2870 	else if (rdev->desc->ramp_delay)
2871 		ramp_delay = rdev->desc->ramp_delay;
2872 
2873 	if (ramp_delay == 0) {
2874 		rdev_warn(rdev, "ramp_delay not set\n");
2875 		return 0;
2876 	}
2877 
2878 	/* sanity check */
2879 	if (!rdev->desc->ops->list_voltage)
2880 		return -EINVAL;
2881 
2882 	old_volt = rdev->desc->ops->list_voltage(rdev, old_selector);
2883 	new_volt = rdev->desc->ops->list_voltage(rdev, new_selector);
2884 
2885 	return DIV_ROUND_UP(abs(new_volt - old_volt), ramp_delay);
2886 }
2887 EXPORT_SYMBOL_GPL(regulator_set_voltage_time_sel);
2888 
2889 /**
2890  * regulator_sync_voltage - re-apply last regulator output voltage
2891  * @regulator: regulator source
2892  *
2893  * Re-apply the last configured voltage.  This is intended to be used
2894  * where some external control source the consumer is cooperating with
2895  * has caused the configured voltage to change.
2896  */
2897 int regulator_sync_voltage(struct regulator *regulator)
2898 {
2899 	struct regulator_dev *rdev = regulator->rdev;
2900 	int ret, min_uV, max_uV;
2901 
2902 	mutex_lock(&rdev->mutex);
2903 
2904 	if (!rdev->desc->ops->set_voltage &&
2905 	    !rdev->desc->ops->set_voltage_sel) {
2906 		ret = -EINVAL;
2907 		goto out;
2908 	}
2909 
2910 	/* This is only going to work if we've had a voltage configured. */
2911 	if (!regulator->min_uV && !regulator->max_uV) {
2912 		ret = -EINVAL;
2913 		goto out;
2914 	}
2915 
2916 	min_uV = regulator->min_uV;
2917 	max_uV = regulator->max_uV;
2918 
2919 	/* This should be a paranoia check... */
2920 	ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
2921 	if (ret < 0)
2922 		goto out;
2923 
2924 	ret = regulator_check_consumers(rdev, &min_uV, &max_uV);
2925 	if (ret < 0)
2926 		goto out;
2927 
2928 	ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
2929 
2930 out:
2931 	mutex_unlock(&rdev->mutex);
2932 	return ret;
2933 }
2934 EXPORT_SYMBOL_GPL(regulator_sync_voltage);
2935 
2936 static int _regulator_get_voltage(struct regulator_dev *rdev)
2937 {
2938 	int sel, ret;
2939 
2940 	if (rdev->desc->ops->get_voltage_sel) {
2941 		sel = rdev->desc->ops->get_voltage_sel(rdev);
2942 		if (sel < 0)
2943 			return sel;
2944 		ret = rdev->desc->ops->list_voltage(rdev, sel);
2945 	} else if (rdev->desc->ops->get_voltage) {
2946 		ret = rdev->desc->ops->get_voltage(rdev);
2947 	} else if (rdev->desc->ops->list_voltage) {
2948 		ret = rdev->desc->ops->list_voltage(rdev, 0);
2949 	} else if (rdev->desc->fixed_uV && (rdev->desc->n_voltages == 1)) {
2950 		ret = rdev->desc->fixed_uV;
2951 	} else if (rdev->supply) {
2952 		ret = regulator_get_voltage(rdev->supply);
2953 	} else {
2954 		return -EINVAL;
2955 	}
2956 
2957 	if (ret < 0)
2958 		return ret;
2959 	return ret - rdev->constraints->uV_offset;
2960 }
2961 
2962 /**
2963  * regulator_get_voltage - get regulator output voltage
2964  * @regulator: regulator source
2965  *
2966  * This returns the current regulator voltage in uV.
2967  *
2968  * NOTE: If the regulator is disabled it will return the voltage value. This
2969  * function should not be used to determine regulator state.
2970  */
2971 int regulator_get_voltage(struct regulator *regulator)
2972 {
2973 	int ret;
2974 
2975 	mutex_lock(&regulator->rdev->mutex);
2976 
2977 	ret = _regulator_get_voltage(regulator->rdev);
2978 
2979 	mutex_unlock(&regulator->rdev->mutex);
2980 
2981 	return ret;
2982 }
2983 EXPORT_SYMBOL_GPL(regulator_get_voltage);
2984 
2985 /**
2986  * regulator_set_current_limit - set regulator output current limit
2987  * @regulator: regulator source
2988  * @min_uA: Minimum supported current in uA
2989  * @max_uA: Maximum supported current in uA
2990  *
2991  * Sets current sink to the desired output current. This can be set during
2992  * any regulator state. IOW, regulator can be disabled or enabled.
2993  *
2994  * If the regulator is enabled then the current will change to the new value
2995  * immediately otherwise if the regulator is disabled the regulator will
2996  * output at the new current when enabled.
2997  *
2998  * NOTE: Regulator system constraints must be set for this regulator before
2999  * calling this function otherwise this call will fail.
3000  */
3001 int regulator_set_current_limit(struct regulator *regulator,
3002 			       int min_uA, int max_uA)
3003 {
3004 	struct regulator_dev *rdev = regulator->rdev;
3005 	int ret;
3006 
3007 	mutex_lock(&rdev->mutex);
3008 
3009 	/* sanity check */
3010 	if (!rdev->desc->ops->set_current_limit) {
3011 		ret = -EINVAL;
3012 		goto out;
3013 	}
3014 
3015 	/* constraints check */
3016 	ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
3017 	if (ret < 0)
3018 		goto out;
3019 
3020 	ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
3021 out:
3022 	mutex_unlock(&rdev->mutex);
3023 	return ret;
3024 }
3025 EXPORT_SYMBOL_GPL(regulator_set_current_limit);
3026 
3027 static int _regulator_get_current_limit(struct regulator_dev *rdev)
3028 {
3029 	int ret;
3030 
3031 	mutex_lock(&rdev->mutex);
3032 
3033 	/* sanity check */
3034 	if (!rdev->desc->ops->get_current_limit) {
3035 		ret = -EINVAL;
3036 		goto out;
3037 	}
3038 
3039 	ret = rdev->desc->ops->get_current_limit(rdev);
3040 out:
3041 	mutex_unlock(&rdev->mutex);
3042 	return ret;
3043 }
3044 
3045 /**
3046  * regulator_get_current_limit - get regulator output current
3047  * @regulator: regulator source
3048  *
3049  * This returns the current supplied by the specified current sink in uA.
3050  *
3051  * NOTE: If the regulator is disabled it will return the current value. This
3052  * function should not be used to determine regulator state.
3053  */
3054 int regulator_get_current_limit(struct regulator *regulator)
3055 {
3056 	return _regulator_get_current_limit(regulator->rdev);
3057 }
3058 EXPORT_SYMBOL_GPL(regulator_get_current_limit);
3059 
3060 /**
3061  * regulator_set_mode - set regulator operating mode
3062  * @regulator: regulator source
3063  * @mode: operating mode - one of the REGULATOR_MODE constants
3064  *
3065  * Set regulator operating mode to increase regulator efficiency or improve
3066  * regulation performance.
3067  *
3068  * NOTE: Regulator system constraints must be set for this regulator before
3069  * calling this function otherwise this call will fail.
3070  */
3071 int regulator_set_mode(struct regulator *regulator, unsigned int mode)
3072 {
3073 	struct regulator_dev *rdev = regulator->rdev;
3074 	int ret;
3075 	int regulator_curr_mode;
3076 
3077 	mutex_lock(&rdev->mutex);
3078 
3079 	/* sanity check */
3080 	if (!rdev->desc->ops->set_mode) {
3081 		ret = -EINVAL;
3082 		goto out;
3083 	}
3084 
3085 	/* return if the same mode is requested */
3086 	if (rdev->desc->ops->get_mode) {
3087 		regulator_curr_mode = rdev->desc->ops->get_mode(rdev);
3088 		if (regulator_curr_mode == mode) {
3089 			ret = 0;
3090 			goto out;
3091 		}
3092 	}
3093 
3094 	/* constraints check */
3095 	ret = regulator_mode_constrain(rdev, &mode);
3096 	if (ret < 0)
3097 		goto out;
3098 
3099 	ret = rdev->desc->ops->set_mode(rdev, mode);
3100 out:
3101 	mutex_unlock(&rdev->mutex);
3102 	return ret;
3103 }
3104 EXPORT_SYMBOL_GPL(regulator_set_mode);
3105 
3106 static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
3107 {
3108 	int ret;
3109 
3110 	mutex_lock(&rdev->mutex);
3111 
3112 	/* sanity check */
3113 	if (!rdev->desc->ops->get_mode) {
3114 		ret = -EINVAL;
3115 		goto out;
3116 	}
3117 
3118 	ret = rdev->desc->ops->get_mode(rdev);
3119 out:
3120 	mutex_unlock(&rdev->mutex);
3121 	return ret;
3122 }
3123 
3124 /**
3125  * regulator_get_mode - get regulator operating mode
3126  * @regulator: regulator source
3127  *
3128  * Get the current regulator operating mode.
3129  */
3130 unsigned int regulator_get_mode(struct regulator *regulator)
3131 {
3132 	return _regulator_get_mode(regulator->rdev);
3133 }
3134 EXPORT_SYMBOL_GPL(regulator_get_mode);
3135 
3136 /**
3137  * regulator_set_load - set regulator load
3138  * @regulator: regulator source
3139  * @uA_load: load current
3140  *
3141  * Notifies the regulator core of a new device load. This is then used by
3142  * DRMS (if enabled by constraints) to set the most efficient regulator
3143  * operating mode for the new regulator loading.
3144  *
3145  * Consumer devices notify their supply regulator of the maximum power
3146  * they will require (can be taken from device datasheet in the power
3147  * consumption tables) when they change operational status and hence power
3148  * state. Examples of operational state changes that can affect power
3149  * consumption are :-
3150  *
3151  *    o Device is opened / closed.
3152  *    o Device I/O is about to begin or has just finished.
3153  *    o Device is idling in between work.
3154  *
3155  * This information is also exported via sysfs to userspace.
3156  *
3157  * DRMS will sum the total requested load on the regulator and change
3158  * to the most efficient operating mode if platform constraints allow.
3159  *
3160  * On error a negative errno is returned.
3161  */
3162 int regulator_set_load(struct regulator *regulator, int uA_load)
3163 {
3164 	struct regulator_dev *rdev = regulator->rdev;
3165 	int ret;
3166 
3167 	mutex_lock(&rdev->mutex);
3168 	regulator->uA_load = uA_load;
3169 	ret = drms_uA_update(rdev);
3170 	mutex_unlock(&rdev->mutex);
3171 
3172 	return ret;
3173 }
3174 EXPORT_SYMBOL_GPL(regulator_set_load);
3175 
3176 /**
3177  * regulator_allow_bypass - allow the regulator to go into bypass mode
3178  *
3179  * @regulator: Regulator to configure
3180  * @enable: enable or disable bypass mode
3181  *
3182  * Allow the regulator to go into bypass mode if all other consumers
3183  * for the regulator also enable bypass mode and the machine
3184  * constraints allow this.  Bypass mode means that the regulator is
3185  * simply passing the input directly to the output with no regulation.
3186  */
3187 int regulator_allow_bypass(struct regulator *regulator, bool enable)
3188 {
3189 	struct regulator_dev *rdev = regulator->rdev;
3190 	int ret = 0;
3191 
3192 	if (!rdev->desc->ops->set_bypass)
3193 		return 0;
3194 
3195 	if (rdev->constraints &&
3196 	    !(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_BYPASS))
3197 		return 0;
3198 
3199 	mutex_lock(&rdev->mutex);
3200 
3201 	if (enable && !regulator->bypass) {
3202 		rdev->bypass_count++;
3203 
3204 		if (rdev->bypass_count == rdev->open_count) {
3205 			ret = rdev->desc->ops->set_bypass(rdev, enable);
3206 			if (ret != 0)
3207 				rdev->bypass_count--;
3208 		}
3209 
3210 	} else if (!enable && regulator->bypass) {
3211 		rdev->bypass_count--;
3212 
3213 		if (rdev->bypass_count != rdev->open_count) {
3214 			ret = rdev->desc->ops->set_bypass(rdev, enable);
3215 			if (ret != 0)
3216 				rdev->bypass_count++;
3217 		}
3218 	}
3219 
3220 	if (ret == 0)
3221 		regulator->bypass = enable;
3222 
3223 	mutex_unlock(&rdev->mutex);
3224 
3225 	return ret;
3226 }
3227 EXPORT_SYMBOL_GPL(regulator_allow_bypass);
3228 
3229 /**
3230  * regulator_register_notifier - register regulator event notifier
3231  * @regulator: regulator source
3232  * @nb: notifier block
3233  *
3234  * Register notifier block to receive regulator events.
3235  */
3236 int regulator_register_notifier(struct regulator *regulator,
3237 			      struct notifier_block *nb)
3238 {
3239 	return blocking_notifier_chain_register(&regulator->rdev->notifier,
3240 						nb);
3241 }
3242 EXPORT_SYMBOL_GPL(regulator_register_notifier);
3243 
3244 /**
3245  * regulator_unregister_notifier - unregister regulator event notifier
3246  * @regulator: regulator source
3247  * @nb: notifier block
3248  *
3249  * Unregister regulator event notifier block.
3250  */
3251 int regulator_unregister_notifier(struct regulator *regulator,
3252 				struct notifier_block *nb)
3253 {
3254 	return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
3255 						  nb);
3256 }
3257 EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
3258 
3259 /* notify regulator consumers and downstream regulator consumers.
3260  * Note mutex must be held by caller.
3261  */
3262 static int _notifier_call_chain(struct regulator_dev *rdev,
3263 				  unsigned long event, void *data)
3264 {
3265 	/* call rdev chain first */
3266 	return blocking_notifier_call_chain(&rdev->notifier, event, data);
3267 }
3268 
3269 /**
3270  * regulator_bulk_get - get multiple regulator consumers
3271  *
3272  * @dev:           Device to supply
3273  * @num_consumers: Number of consumers to register
3274  * @consumers:     Configuration of consumers; clients are stored here.
3275  *
3276  * @return 0 on success, an errno on failure.
3277  *
3278  * This helper function allows drivers to get several regulator
3279  * consumers in one operation.  If any of the regulators cannot be
3280  * acquired then any regulators that were allocated will be freed
3281  * before returning to the caller.
3282  */
3283 int regulator_bulk_get(struct device *dev, int num_consumers,
3284 		       struct regulator_bulk_data *consumers)
3285 {
3286 	int i;
3287 	int ret;
3288 
3289 	for (i = 0; i < num_consumers; i++)
3290 		consumers[i].consumer = NULL;
3291 
3292 	for (i = 0; i < num_consumers; i++) {
3293 		consumers[i].consumer = regulator_get(dev,
3294 						      consumers[i].supply);
3295 		if (IS_ERR(consumers[i].consumer)) {
3296 			ret = PTR_ERR(consumers[i].consumer);
3297 			dev_err(dev, "Failed to get supply '%s': %d\n",
3298 				consumers[i].supply, ret);
3299 			consumers[i].consumer = NULL;
3300 			goto err;
3301 		}
3302 	}
3303 
3304 	return 0;
3305 
3306 err:
3307 	while (--i >= 0)
3308 		regulator_put(consumers[i].consumer);
3309 
3310 	return ret;
3311 }
3312 EXPORT_SYMBOL_GPL(regulator_bulk_get);
3313 
3314 static void regulator_bulk_enable_async(void *data, async_cookie_t cookie)
3315 {
3316 	struct regulator_bulk_data *bulk = data;
3317 
3318 	bulk->ret = regulator_enable(bulk->consumer);
3319 }
3320 
3321 /**
3322  * regulator_bulk_enable - enable multiple regulator consumers
3323  *
3324  * @num_consumers: Number of consumers
3325  * @consumers:     Consumer data; clients are stored here.
3326  * @return         0 on success, an errno on failure
3327  *
3328  * This convenience API allows consumers to enable multiple regulator
3329  * clients in a single API call.  If any consumers cannot be enabled
3330  * then any others that were enabled will be disabled again prior to
3331  * return.
3332  */
3333 int regulator_bulk_enable(int num_consumers,
3334 			  struct regulator_bulk_data *consumers)
3335 {
3336 	ASYNC_DOMAIN_EXCLUSIVE(async_domain);
3337 	int i;
3338 	int ret = 0;
3339 
3340 	for (i = 0; i < num_consumers; i++) {
3341 		if (consumers[i].consumer->always_on)
3342 			consumers[i].ret = 0;
3343 		else
3344 			async_schedule_domain(regulator_bulk_enable_async,
3345 					      &consumers[i], &async_domain);
3346 	}
3347 
3348 	async_synchronize_full_domain(&async_domain);
3349 
3350 	/* If any consumer failed we need to unwind any that succeeded */
3351 	for (i = 0; i < num_consumers; i++) {
3352 		if (consumers[i].ret != 0) {
3353 			ret = consumers[i].ret;
3354 			goto err;
3355 		}
3356 	}
3357 
3358 	return 0;
3359 
3360 err:
3361 	for (i = 0; i < num_consumers; i++) {
3362 		if (consumers[i].ret < 0)
3363 			pr_err("Failed to enable %s: %d\n", consumers[i].supply,
3364 			       consumers[i].ret);
3365 		else
3366 			regulator_disable(consumers[i].consumer);
3367 	}
3368 
3369 	return ret;
3370 }
3371 EXPORT_SYMBOL_GPL(regulator_bulk_enable);
3372 
3373 /**
3374  * regulator_bulk_disable - disable multiple regulator consumers
3375  *
3376  * @num_consumers: Number of consumers
3377  * @consumers:     Consumer data; clients are stored here.
3378  * @return         0 on success, an errno on failure
3379  *
3380  * This convenience API allows consumers to disable multiple regulator
3381  * clients in a single API call.  If any consumers cannot be disabled
3382  * then any others that were disabled will be enabled again prior to
3383  * return.
3384  */
3385 int regulator_bulk_disable(int num_consumers,
3386 			   struct regulator_bulk_data *consumers)
3387 {
3388 	int i;
3389 	int ret, r;
3390 
3391 	for (i = num_consumers - 1; i >= 0; --i) {
3392 		ret = regulator_disable(consumers[i].consumer);
3393 		if (ret != 0)
3394 			goto err;
3395 	}
3396 
3397 	return 0;
3398 
3399 err:
3400 	pr_err("Failed to disable %s: %d\n", consumers[i].supply, ret);
3401 	for (++i; i < num_consumers; ++i) {
3402 		r = regulator_enable(consumers[i].consumer);
3403 		if (r != 0)
3404 			pr_err("Failed to reename %s: %d\n",
3405 			       consumers[i].supply, r);
3406 	}
3407 
3408 	return ret;
3409 }
3410 EXPORT_SYMBOL_GPL(regulator_bulk_disable);
3411 
3412 /**
3413  * regulator_bulk_force_disable - force disable multiple regulator consumers
3414  *
3415  * @num_consumers: Number of consumers
3416  * @consumers:     Consumer data; clients are stored here.
3417  * @return         0 on success, an errno on failure
3418  *
3419  * This convenience API allows consumers to forcibly disable multiple regulator
3420  * clients in a single API call.
3421  * NOTE: This should be used for situations when device damage will
3422  * likely occur if the regulators are not disabled (e.g. over temp).
3423  * Although regulator_force_disable function call for some consumers can
3424  * return error numbers, the function is called for all consumers.
3425  */
3426 int regulator_bulk_force_disable(int num_consumers,
3427 			   struct regulator_bulk_data *consumers)
3428 {
3429 	int i;
3430 	int ret;
3431 
3432 	for (i = 0; i < num_consumers; i++)
3433 		consumers[i].ret =
3434 			    regulator_force_disable(consumers[i].consumer);
3435 
3436 	for (i = 0; i < num_consumers; i++) {
3437 		if (consumers[i].ret != 0) {
3438 			ret = consumers[i].ret;
3439 			goto out;
3440 		}
3441 	}
3442 
3443 	return 0;
3444 out:
3445 	return ret;
3446 }
3447 EXPORT_SYMBOL_GPL(regulator_bulk_force_disable);
3448 
3449 /**
3450  * regulator_bulk_free - free multiple regulator consumers
3451  *
3452  * @num_consumers: Number of consumers
3453  * @consumers:     Consumer data; clients are stored here.
3454  *
3455  * This convenience API allows consumers to free multiple regulator
3456  * clients in a single API call.
3457  */
3458 void regulator_bulk_free(int num_consumers,
3459 			 struct regulator_bulk_data *consumers)
3460 {
3461 	int i;
3462 
3463 	for (i = 0; i < num_consumers; i++) {
3464 		regulator_put(consumers[i].consumer);
3465 		consumers[i].consumer = NULL;
3466 	}
3467 }
3468 EXPORT_SYMBOL_GPL(regulator_bulk_free);
3469 
3470 /**
3471  * regulator_notifier_call_chain - call regulator event notifier
3472  * @rdev: regulator source
3473  * @event: notifier block
3474  * @data: callback-specific data.
3475  *
3476  * Called by regulator drivers to notify clients a regulator event has
3477  * occurred. We also notify regulator clients downstream.
3478  * Note lock must be held by caller.
3479  */
3480 int regulator_notifier_call_chain(struct regulator_dev *rdev,
3481 				  unsigned long event, void *data)
3482 {
3483 	lockdep_assert_held_once(&rdev->mutex);
3484 
3485 	_notifier_call_chain(rdev, event, data);
3486 	return NOTIFY_DONE;
3487 
3488 }
3489 EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
3490 
3491 /**
3492  * regulator_mode_to_status - convert a regulator mode into a status
3493  *
3494  * @mode: Mode to convert
3495  *
3496  * Convert a regulator mode into a status.
3497  */
3498 int regulator_mode_to_status(unsigned int mode)
3499 {
3500 	switch (mode) {
3501 	case REGULATOR_MODE_FAST:
3502 		return REGULATOR_STATUS_FAST;
3503 	case REGULATOR_MODE_NORMAL:
3504 		return REGULATOR_STATUS_NORMAL;
3505 	case REGULATOR_MODE_IDLE:
3506 		return REGULATOR_STATUS_IDLE;
3507 	case REGULATOR_MODE_STANDBY:
3508 		return REGULATOR_STATUS_STANDBY;
3509 	default:
3510 		return REGULATOR_STATUS_UNDEFINED;
3511 	}
3512 }
3513 EXPORT_SYMBOL_GPL(regulator_mode_to_status);
3514 
3515 static struct attribute *regulator_dev_attrs[] = {
3516 	&dev_attr_name.attr,
3517 	&dev_attr_num_users.attr,
3518 	&dev_attr_type.attr,
3519 	&dev_attr_microvolts.attr,
3520 	&dev_attr_microamps.attr,
3521 	&dev_attr_opmode.attr,
3522 	&dev_attr_state.attr,
3523 	&dev_attr_status.attr,
3524 	&dev_attr_bypass.attr,
3525 	&dev_attr_requested_microamps.attr,
3526 	&dev_attr_min_microvolts.attr,
3527 	&dev_attr_max_microvolts.attr,
3528 	&dev_attr_min_microamps.attr,
3529 	&dev_attr_max_microamps.attr,
3530 	&dev_attr_suspend_standby_state.attr,
3531 	&dev_attr_suspend_mem_state.attr,
3532 	&dev_attr_suspend_disk_state.attr,
3533 	&dev_attr_suspend_standby_microvolts.attr,
3534 	&dev_attr_suspend_mem_microvolts.attr,
3535 	&dev_attr_suspend_disk_microvolts.attr,
3536 	&dev_attr_suspend_standby_mode.attr,
3537 	&dev_attr_suspend_mem_mode.attr,
3538 	&dev_attr_suspend_disk_mode.attr,
3539 	NULL
3540 };
3541 
3542 /*
3543  * To avoid cluttering sysfs (and memory) with useless state, only
3544  * create attributes that can be meaningfully displayed.
3545  */
3546 static umode_t regulator_attr_is_visible(struct kobject *kobj,
3547 					 struct attribute *attr, int idx)
3548 {
3549 	struct device *dev = kobj_to_dev(kobj);
3550 	struct regulator_dev *rdev = container_of(dev, struct regulator_dev, dev);
3551 	const struct regulator_ops *ops = rdev->desc->ops;
3552 	umode_t mode = attr->mode;
3553 
3554 	/* these three are always present */
3555 	if (attr == &dev_attr_name.attr ||
3556 	    attr == &dev_attr_num_users.attr ||
3557 	    attr == &dev_attr_type.attr)
3558 		return mode;
3559 
3560 	/* some attributes need specific methods to be displayed */
3561 	if (attr == &dev_attr_microvolts.attr) {
3562 		if ((ops->get_voltage && ops->get_voltage(rdev) >= 0) ||
3563 		    (ops->get_voltage_sel && ops->get_voltage_sel(rdev) >= 0) ||
3564 		    (ops->list_voltage && ops->list_voltage(rdev, 0) >= 0) ||
3565 		    (rdev->desc->fixed_uV && rdev->desc->n_voltages == 1))
3566 			return mode;
3567 		return 0;
3568 	}
3569 
3570 	if (attr == &dev_attr_microamps.attr)
3571 		return ops->get_current_limit ? mode : 0;
3572 
3573 	if (attr == &dev_attr_opmode.attr)
3574 		return ops->get_mode ? mode : 0;
3575 
3576 	if (attr == &dev_attr_state.attr)
3577 		return (rdev->ena_pin || ops->is_enabled) ? mode : 0;
3578 
3579 	if (attr == &dev_attr_status.attr)
3580 		return ops->get_status ? mode : 0;
3581 
3582 	if (attr == &dev_attr_bypass.attr)
3583 		return ops->get_bypass ? mode : 0;
3584 
3585 	/* some attributes are type-specific */
3586 	if (attr == &dev_attr_requested_microamps.attr)
3587 		return rdev->desc->type == REGULATOR_CURRENT ? mode : 0;
3588 
3589 	/* constraints need specific supporting methods */
3590 	if (attr == &dev_attr_min_microvolts.attr ||
3591 	    attr == &dev_attr_max_microvolts.attr)
3592 		return (ops->set_voltage || ops->set_voltage_sel) ? mode : 0;
3593 
3594 	if (attr == &dev_attr_min_microamps.attr ||
3595 	    attr == &dev_attr_max_microamps.attr)
3596 		return ops->set_current_limit ? mode : 0;
3597 
3598 	if (attr == &dev_attr_suspend_standby_state.attr ||
3599 	    attr == &dev_attr_suspend_mem_state.attr ||
3600 	    attr == &dev_attr_suspend_disk_state.attr)
3601 		return mode;
3602 
3603 	if (attr == &dev_attr_suspend_standby_microvolts.attr ||
3604 	    attr == &dev_attr_suspend_mem_microvolts.attr ||
3605 	    attr == &dev_attr_suspend_disk_microvolts.attr)
3606 		return ops->set_suspend_voltage ? mode : 0;
3607 
3608 	if (attr == &dev_attr_suspend_standby_mode.attr ||
3609 	    attr == &dev_attr_suspend_mem_mode.attr ||
3610 	    attr == &dev_attr_suspend_disk_mode.attr)
3611 		return ops->set_suspend_mode ? mode : 0;
3612 
3613 	return mode;
3614 }
3615 
3616 static const struct attribute_group regulator_dev_group = {
3617 	.attrs = regulator_dev_attrs,
3618 	.is_visible = regulator_attr_is_visible,
3619 };
3620 
3621 static const struct attribute_group *regulator_dev_groups[] = {
3622 	&regulator_dev_group,
3623 	NULL
3624 };
3625 
3626 static void regulator_dev_release(struct device *dev)
3627 {
3628 	struct regulator_dev *rdev = dev_get_drvdata(dev);
3629 
3630 	kfree(rdev->constraints);
3631 	of_node_put(rdev->dev.of_node);
3632 	kfree(rdev);
3633 }
3634 
3635 static struct class regulator_class = {
3636 	.name = "regulator",
3637 	.dev_release = regulator_dev_release,
3638 	.dev_groups = regulator_dev_groups,
3639 };
3640 
3641 static void rdev_init_debugfs(struct regulator_dev *rdev)
3642 {
3643 	struct device *parent = rdev->dev.parent;
3644 	const char *rname = rdev_get_name(rdev);
3645 	char name[NAME_MAX];
3646 
3647 	/* Avoid duplicate debugfs directory names */
3648 	if (parent && rname == rdev->desc->name) {
3649 		snprintf(name, sizeof(name), "%s-%s", dev_name(parent),
3650 			 rname);
3651 		rname = name;
3652 	}
3653 
3654 	rdev->debugfs = debugfs_create_dir(rname, debugfs_root);
3655 	if (!rdev->debugfs) {
3656 		rdev_warn(rdev, "Failed to create debugfs directory\n");
3657 		return;
3658 	}
3659 
3660 	debugfs_create_u32("use_count", 0444, rdev->debugfs,
3661 			   &rdev->use_count);
3662 	debugfs_create_u32("open_count", 0444, rdev->debugfs,
3663 			   &rdev->open_count);
3664 	debugfs_create_u32("bypass_count", 0444, rdev->debugfs,
3665 			   &rdev->bypass_count);
3666 }
3667 
3668 /**
3669  * regulator_register - register regulator
3670  * @regulator_desc: regulator to register
3671  * @cfg: runtime configuration for regulator
3672  *
3673  * Called by regulator drivers to register a regulator.
3674  * Returns a valid pointer to struct regulator_dev on success
3675  * or an ERR_PTR() on error.
3676  */
3677 struct regulator_dev *
3678 regulator_register(const struct regulator_desc *regulator_desc,
3679 		   const struct regulator_config *cfg)
3680 {
3681 	const struct regulation_constraints *constraints = NULL;
3682 	const struct regulator_init_data *init_data;
3683 	struct regulator_config *config = NULL;
3684 	static atomic_t regulator_no = ATOMIC_INIT(-1);
3685 	struct regulator_dev *rdev;
3686 	struct device *dev;
3687 	int ret, i;
3688 
3689 	if (regulator_desc == NULL || cfg == NULL)
3690 		return ERR_PTR(-EINVAL);
3691 
3692 	dev = cfg->dev;
3693 	WARN_ON(!dev);
3694 
3695 	if (regulator_desc->name == NULL || regulator_desc->ops == NULL)
3696 		return ERR_PTR(-EINVAL);
3697 
3698 	if (regulator_desc->type != REGULATOR_VOLTAGE &&
3699 	    regulator_desc->type != REGULATOR_CURRENT)
3700 		return ERR_PTR(-EINVAL);
3701 
3702 	/* Only one of each should be implemented */
3703 	WARN_ON(regulator_desc->ops->get_voltage &&
3704 		regulator_desc->ops->get_voltage_sel);
3705 	WARN_ON(regulator_desc->ops->set_voltage &&
3706 		regulator_desc->ops->set_voltage_sel);
3707 
3708 	/* If we're using selectors we must implement list_voltage. */
3709 	if (regulator_desc->ops->get_voltage_sel &&
3710 	    !regulator_desc->ops->list_voltage) {
3711 		return ERR_PTR(-EINVAL);
3712 	}
3713 	if (regulator_desc->ops->set_voltage_sel &&
3714 	    !regulator_desc->ops->list_voltage) {
3715 		return ERR_PTR(-EINVAL);
3716 	}
3717 
3718 	rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
3719 	if (rdev == NULL)
3720 		return ERR_PTR(-ENOMEM);
3721 
3722 	/*
3723 	 * Duplicate the config so the driver could override it after
3724 	 * parsing init data.
3725 	 */
3726 	config = kmemdup(cfg, sizeof(*cfg), GFP_KERNEL);
3727 	if (config == NULL) {
3728 		kfree(rdev);
3729 		return ERR_PTR(-ENOMEM);
3730 	}
3731 
3732 	init_data = regulator_of_get_init_data(dev, regulator_desc, config,
3733 					       &rdev->dev.of_node);
3734 	if (!init_data) {
3735 		init_data = config->init_data;
3736 		rdev->dev.of_node = of_node_get(config->of_node);
3737 	}
3738 
3739 	mutex_lock(&regulator_list_mutex);
3740 
3741 	mutex_init(&rdev->mutex);
3742 	rdev->reg_data = config->driver_data;
3743 	rdev->owner = regulator_desc->owner;
3744 	rdev->desc = regulator_desc;
3745 	if (config->regmap)
3746 		rdev->regmap = config->regmap;
3747 	else if (dev_get_regmap(dev, NULL))
3748 		rdev->regmap = dev_get_regmap(dev, NULL);
3749 	else if (dev->parent)
3750 		rdev->regmap = dev_get_regmap(dev->parent, NULL);
3751 	INIT_LIST_HEAD(&rdev->consumer_list);
3752 	INIT_LIST_HEAD(&rdev->list);
3753 	BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
3754 	INIT_DELAYED_WORK(&rdev->disable_work, regulator_disable_work);
3755 
3756 	/* preform any regulator specific init */
3757 	if (init_data && init_data->regulator_init) {
3758 		ret = init_data->regulator_init(rdev->reg_data);
3759 		if (ret < 0)
3760 			goto clean;
3761 	}
3762 
3763 	/* register with sysfs */
3764 	rdev->dev.class = &regulator_class;
3765 	rdev->dev.parent = dev;
3766 	dev_set_name(&rdev->dev, "regulator.%lu",
3767 		    (unsigned long) atomic_inc_return(&regulator_no));
3768 	ret = device_register(&rdev->dev);
3769 	if (ret != 0) {
3770 		put_device(&rdev->dev);
3771 		goto clean;
3772 	}
3773 
3774 	dev_set_drvdata(&rdev->dev, rdev);
3775 
3776 	if ((config->ena_gpio || config->ena_gpio_initialized) &&
3777 	    gpio_is_valid(config->ena_gpio)) {
3778 		ret = regulator_ena_gpio_request(rdev, config);
3779 		if (ret != 0) {
3780 			rdev_err(rdev, "Failed to request enable GPIO%d: %d\n",
3781 				 config->ena_gpio, ret);
3782 			goto wash;
3783 		}
3784 	}
3785 
3786 	/* set regulator constraints */
3787 	if (init_data)
3788 		constraints = &init_data->constraints;
3789 
3790 	ret = set_machine_constraints(rdev, constraints);
3791 	if (ret < 0)
3792 		goto scrub;
3793 
3794 	if (init_data && init_data->supply_regulator)
3795 		rdev->supply_name = init_data->supply_regulator;
3796 	else if (regulator_desc->supply_name)
3797 		rdev->supply_name = regulator_desc->supply_name;
3798 
3799 	/* add consumers devices */
3800 	if (init_data) {
3801 		for (i = 0; i < init_data->num_consumer_supplies; i++) {
3802 			ret = set_consumer_device_supply(rdev,
3803 				init_data->consumer_supplies[i].dev_name,
3804 				init_data->consumer_supplies[i].supply);
3805 			if (ret < 0) {
3806 				dev_err(dev, "Failed to set supply %s\n",
3807 					init_data->consumer_supplies[i].supply);
3808 				goto unset_supplies;
3809 			}
3810 		}
3811 	}
3812 
3813 	list_add(&rdev->list, &regulator_list);
3814 
3815 	rdev_init_debugfs(rdev);
3816 out:
3817 	mutex_unlock(&regulator_list_mutex);
3818 	kfree(config);
3819 	return rdev;
3820 
3821 unset_supplies:
3822 	unset_regulator_supplies(rdev);
3823 
3824 scrub:
3825 	regulator_ena_gpio_free(rdev);
3826 	kfree(rdev->constraints);
3827 wash:
3828 	device_unregister(&rdev->dev);
3829 	/* device core frees rdev */
3830 	rdev = ERR_PTR(ret);
3831 	goto out;
3832 
3833 clean:
3834 	kfree(rdev);
3835 	rdev = ERR_PTR(ret);
3836 	goto out;
3837 }
3838 EXPORT_SYMBOL_GPL(regulator_register);
3839 
3840 /**
3841  * regulator_unregister - unregister regulator
3842  * @rdev: regulator to unregister
3843  *
3844  * Called by regulator drivers to unregister a regulator.
3845  */
3846 void regulator_unregister(struct regulator_dev *rdev)
3847 {
3848 	if (rdev == NULL)
3849 		return;
3850 
3851 	if (rdev->supply) {
3852 		while (rdev->use_count--)
3853 			regulator_disable(rdev->supply);
3854 		regulator_put(rdev->supply);
3855 	}
3856 	mutex_lock(&regulator_list_mutex);
3857 	debugfs_remove_recursive(rdev->debugfs);
3858 	flush_work(&rdev->disable_work.work);
3859 	WARN_ON(rdev->open_count);
3860 	unset_regulator_supplies(rdev);
3861 	list_del(&rdev->list);
3862 	mutex_unlock(&regulator_list_mutex);
3863 	regulator_ena_gpio_free(rdev);
3864 	device_unregister(&rdev->dev);
3865 }
3866 EXPORT_SYMBOL_GPL(regulator_unregister);
3867 
3868 /**
3869  * regulator_suspend_prepare - prepare regulators for system wide suspend
3870  * @state: system suspend state
3871  *
3872  * Configure each regulator with it's suspend operating parameters for state.
3873  * This will usually be called by machine suspend code prior to supending.
3874  */
3875 int regulator_suspend_prepare(suspend_state_t state)
3876 {
3877 	struct regulator_dev *rdev;
3878 	int ret = 0;
3879 
3880 	/* ON is handled by regulator active state */
3881 	if (state == PM_SUSPEND_ON)
3882 		return -EINVAL;
3883 
3884 	mutex_lock(&regulator_list_mutex);
3885 	list_for_each_entry(rdev, &regulator_list, list) {
3886 
3887 		mutex_lock(&rdev->mutex);
3888 		ret = suspend_prepare(rdev, state);
3889 		mutex_unlock(&rdev->mutex);
3890 
3891 		if (ret < 0) {
3892 			rdev_err(rdev, "failed to prepare\n");
3893 			goto out;
3894 		}
3895 	}
3896 out:
3897 	mutex_unlock(&regulator_list_mutex);
3898 	return ret;
3899 }
3900 EXPORT_SYMBOL_GPL(regulator_suspend_prepare);
3901 
3902 /**
3903  * regulator_suspend_finish - resume regulators from system wide suspend
3904  *
3905  * Turn on regulators that might be turned off by regulator_suspend_prepare
3906  * and that should be turned on according to the regulators properties.
3907  */
3908 int regulator_suspend_finish(void)
3909 {
3910 	struct regulator_dev *rdev;
3911 	int ret = 0, error;
3912 
3913 	mutex_lock(&regulator_list_mutex);
3914 	list_for_each_entry(rdev, &regulator_list, list) {
3915 		mutex_lock(&rdev->mutex);
3916 		if (rdev->use_count > 0  || rdev->constraints->always_on) {
3917 			if (!_regulator_is_enabled(rdev)) {
3918 				error = _regulator_do_enable(rdev);
3919 				if (error)
3920 					ret = error;
3921 			}
3922 		} else {
3923 			if (!have_full_constraints())
3924 				goto unlock;
3925 			if (!_regulator_is_enabled(rdev))
3926 				goto unlock;
3927 
3928 			error = _regulator_do_disable(rdev);
3929 			if (error)
3930 				ret = error;
3931 		}
3932 unlock:
3933 		mutex_unlock(&rdev->mutex);
3934 	}
3935 	mutex_unlock(&regulator_list_mutex);
3936 	return ret;
3937 }
3938 EXPORT_SYMBOL_GPL(regulator_suspend_finish);
3939 
3940 /**
3941  * regulator_has_full_constraints - the system has fully specified constraints
3942  *
3943  * Calling this function will cause the regulator API to disable all
3944  * regulators which have a zero use count and don't have an always_on
3945  * constraint in a late_initcall.
3946  *
3947  * The intention is that this will become the default behaviour in a
3948  * future kernel release so users are encouraged to use this facility
3949  * now.
3950  */
3951 void regulator_has_full_constraints(void)
3952 {
3953 	has_full_constraints = 1;
3954 }
3955 EXPORT_SYMBOL_GPL(regulator_has_full_constraints);
3956 
3957 /**
3958  * rdev_get_drvdata - get rdev regulator driver data
3959  * @rdev: regulator
3960  *
3961  * Get rdev regulator driver private data. This call can be used in the
3962  * regulator driver context.
3963  */
3964 void *rdev_get_drvdata(struct regulator_dev *rdev)
3965 {
3966 	return rdev->reg_data;
3967 }
3968 EXPORT_SYMBOL_GPL(rdev_get_drvdata);
3969 
3970 /**
3971  * regulator_get_drvdata - get regulator driver data
3972  * @regulator: regulator
3973  *
3974  * Get regulator driver private data. This call can be used in the consumer
3975  * driver context when non API regulator specific functions need to be called.
3976  */
3977 void *regulator_get_drvdata(struct regulator *regulator)
3978 {
3979 	return regulator->rdev->reg_data;
3980 }
3981 EXPORT_SYMBOL_GPL(regulator_get_drvdata);
3982 
3983 /**
3984  * regulator_set_drvdata - set regulator driver data
3985  * @regulator: regulator
3986  * @data: data
3987  */
3988 void regulator_set_drvdata(struct regulator *regulator, void *data)
3989 {
3990 	regulator->rdev->reg_data = data;
3991 }
3992 EXPORT_SYMBOL_GPL(regulator_set_drvdata);
3993 
3994 /**
3995  * regulator_get_id - get regulator ID
3996  * @rdev: regulator
3997  */
3998 int rdev_get_id(struct regulator_dev *rdev)
3999 {
4000 	return rdev->desc->id;
4001 }
4002 EXPORT_SYMBOL_GPL(rdev_get_id);
4003 
4004 struct device *rdev_get_dev(struct regulator_dev *rdev)
4005 {
4006 	return &rdev->dev;
4007 }
4008 EXPORT_SYMBOL_GPL(rdev_get_dev);
4009 
4010 void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
4011 {
4012 	return reg_init_data->driver_data;
4013 }
4014 EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
4015 
4016 #ifdef CONFIG_DEBUG_FS
4017 static ssize_t supply_map_read_file(struct file *file, char __user *user_buf,
4018 				    size_t count, loff_t *ppos)
4019 {
4020 	char *buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
4021 	ssize_t len, ret = 0;
4022 	struct regulator_map *map;
4023 
4024 	if (!buf)
4025 		return -ENOMEM;
4026 
4027 	list_for_each_entry(map, &regulator_map_list, list) {
4028 		len = snprintf(buf + ret, PAGE_SIZE - ret,
4029 			       "%s -> %s.%s\n",
4030 			       rdev_get_name(map->regulator), map->dev_name,
4031 			       map->supply);
4032 		if (len >= 0)
4033 			ret += len;
4034 		if (ret > PAGE_SIZE) {
4035 			ret = PAGE_SIZE;
4036 			break;
4037 		}
4038 	}
4039 
4040 	ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
4041 
4042 	kfree(buf);
4043 
4044 	return ret;
4045 }
4046 #endif
4047 
4048 static const struct file_operations supply_map_fops = {
4049 #ifdef CONFIG_DEBUG_FS
4050 	.read = supply_map_read_file,
4051 	.llseek = default_llseek,
4052 #endif
4053 };
4054 
4055 #ifdef CONFIG_DEBUG_FS
4056 static void regulator_summary_show_subtree(struct seq_file *s,
4057 					   struct regulator_dev *rdev,
4058 					   int level)
4059 {
4060 	struct list_head *list = s->private;
4061 	struct regulator_dev *child;
4062 	struct regulation_constraints *c;
4063 	struct regulator *consumer;
4064 
4065 	if (!rdev)
4066 		return;
4067 
4068 	seq_printf(s, "%*s%-*s %3d %4d %6d ",
4069 		   level * 3 + 1, "",
4070 		   30 - level * 3, rdev_get_name(rdev),
4071 		   rdev->use_count, rdev->open_count, rdev->bypass_count);
4072 
4073 	seq_printf(s, "%5dmV ", _regulator_get_voltage(rdev) / 1000);
4074 	seq_printf(s, "%5dmA ", _regulator_get_current_limit(rdev) / 1000);
4075 
4076 	c = rdev->constraints;
4077 	if (c) {
4078 		switch (rdev->desc->type) {
4079 		case REGULATOR_VOLTAGE:
4080 			seq_printf(s, "%5dmV %5dmV ",
4081 				   c->min_uV / 1000, c->max_uV / 1000);
4082 			break;
4083 		case REGULATOR_CURRENT:
4084 			seq_printf(s, "%5dmA %5dmA ",
4085 				   c->min_uA / 1000, c->max_uA / 1000);
4086 			break;
4087 		}
4088 	}
4089 
4090 	seq_puts(s, "\n");
4091 
4092 	list_for_each_entry(consumer, &rdev->consumer_list, list) {
4093 		if (consumer->dev->class == &regulator_class)
4094 			continue;
4095 
4096 		seq_printf(s, "%*s%-*s ",
4097 			   (level + 1) * 3 + 1, "",
4098 			   30 - (level + 1) * 3, dev_name(consumer->dev));
4099 
4100 		switch (rdev->desc->type) {
4101 		case REGULATOR_VOLTAGE:
4102 			seq_printf(s, "%37dmV %5dmV",
4103 				   consumer->min_uV / 1000,
4104 				   consumer->max_uV / 1000);
4105 			break;
4106 		case REGULATOR_CURRENT:
4107 			break;
4108 		}
4109 
4110 		seq_puts(s, "\n");
4111 	}
4112 
4113 	list_for_each_entry(child, list, list) {
4114 		/* handle only non-root regulators supplied by current rdev */
4115 		if (!child->supply || child->supply->rdev != rdev)
4116 			continue;
4117 
4118 		regulator_summary_show_subtree(s, child, level + 1);
4119 	}
4120 }
4121 
4122 static int regulator_summary_show(struct seq_file *s, void *data)
4123 {
4124 	struct list_head *list = s->private;
4125 	struct regulator_dev *rdev;
4126 
4127 	seq_puts(s, " regulator                      use open bypass voltage current     min     max\n");
4128 	seq_puts(s, "-------------------------------------------------------------------------------\n");
4129 
4130 	mutex_lock(&regulator_list_mutex);
4131 
4132 	list_for_each_entry(rdev, list, list) {
4133 		if (rdev->supply)
4134 			continue;
4135 
4136 		regulator_summary_show_subtree(s, rdev, 0);
4137 	}
4138 
4139 	mutex_unlock(&regulator_list_mutex);
4140 
4141 	return 0;
4142 }
4143 
4144 static int regulator_summary_open(struct inode *inode, struct file *file)
4145 {
4146 	return single_open(file, regulator_summary_show, inode->i_private);
4147 }
4148 #endif
4149 
4150 static const struct file_operations regulator_summary_fops = {
4151 #ifdef CONFIG_DEBUG_FS
4152 	.open		= regulator_summary_open,
4153 	.read		= seq_read,
4154 	.llseek		= seq_lseek,
4155 	.release	= single_release,
4156 #endif
4157 };
4158 
4159 static int __init regulator_init(void)
4160 {
4161 	int ret;
4162 
4163 	ret = class_register(&regulator_class);
4164 
4165 	debugfs_root = debugfs_create_dir("regulator", NULL);
4166 	if (!debugfs_root)
4167 		pr_warn("regulator: Failed to create debugfs directory\n");
4168 
4169 	debugfs_create_file("supply_map", 0444, debugfs_root, NULL,
4170 			    &supply_map_fops);
4171 
4172 	debugfs_create_file("regulator_summary", 0444, debugfs_root,
4173 			    &regulator_list, &regulator_summary_fops);
4174 
4175 	regulator_dummy_init();
4176 
4177 	return ret;
4178 }
4179 
4180 /* init early to allow our consumers to complete system booting */
4181 core_initcall(regulator_init);
4182 
4183 static int __init regulator_late_cleanup(struct device *dev, void *data)
4184 {
4185 	struct regulator_dev *rdev = dev_to_rdev(dev);
4186 	const struct regulator_ops *ops = rdev->desc->ops;
4187 	struct regulation_constraints *c = rdev->constraints;
4188 	int enabled, ret;
4189 
4190 	if (c && c->always_on)
4191 		return 0;
4192 
4193 	if (c && !(c->valid_ops_mask & REGULATOR_CHANGE_STATUS))
4194 		return 0;
4195 
4196 	mutex_lock(&rdev->mutex);
4197 
4198 	if (rdev->use_count)
4199 		goto unlock;
4200 
4201 	/* If we can't read the status assume it's on. */
4202 	if (ops->is_enabled)
4203 		enabled = ops->is_enabled(rdev);
4204 	else
4205 		enabled = 1;
4206 
4207 	if (!enabled)
4208 		goto unlock;
4209 
4210 	if (have_full_constraints()) {
4211 		/* We log since this may kill the system if it goes
4212 		 * wrong. */
4213 		rdev_info(rdev, "disabling\n");
4214 		ret = _regulator_do_disable(rdev);
4215 		if (ret != 0)
4216 			rdev_err(rdev, "couldn't disable: %d\n", ret);
4217 	} else {
4218 		/* The intention is that in future we will
4219 		 * assume that full constraints are provided
4220 		 * so warn even if we aren't going to do
4221 		 * anything here.
4222 		 */
4223 		rdev_warn(rdev, "incomplete constraints, leaving on\n");
4224 	}
4225 
4226 unlock:
4227 	mutex_unlock(&rdev->mutex);
4228 
4229 	return 0;
4230 }
4231 
4232 static int __init regulator_init_complete(void)
4233 {
4234 	/*
4235 	 * Since DT doesn't provide an idiomatic mechanism for
4236 	 * enabling full constraints and since it's much more natural
4237 	 * with DT to provide them just assume that a DT enabled
4238 	 * system has full constraints.
4239 	 */
4240 	if (of_have_populated_dt())
4241 		has_full_constraints = true;
4242 
4243 	/* If we have a full configuration then disable any regulators
4244 	 * we have permission to change the status for and which are
4245 	 * not in use or always_on.  This is effectively the default
4246 	 * for DT and ACPI as they have full constraints.
4247 	 */
4248 	class_for_each_device(&regulator_class, NULL, NULL,
4249 			      regulator_late_cleanup);
4250 
4251 	return 0;
4252 }
4253 late_initcall_sync(regulator_init_complete);
4254