core.c revision 215b8b055de7dad26ab6c10f70130934309cb696
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/of.h>
28#include <linux/regmap.h>
29#include <linux/regulator/of_regulator.h>
30#include <linux/regulator/consumer.h>
31#include <linux/regulator/driver.h>
32#include <linux/regulator/machine.h>
33#include <linux/module.h>
34
35#define CREATE_TRACE_POINTS
36#include <trace/events/regulator.h>
37
38#include "dummy.h"
39
40#define rdev_crit(rdev, fmt, ...)					\
41	pr_crit("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
42#define rdev_err(rdev, fmt, ...)					\
43	pr_err("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
44#define rdev_warn(rdev, fmt, ...)					\
45	pr_warn("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
46#define rdev_info(rdev, fmt, ...)					\
47	pr_info("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
48#define rdev_dbg(rdev, fmt, ...)					\
49	pr_debug("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
50
51static DEFINE_MUTEX(regulator_list_mutex);
52static LIST_HEAD(regulator_list);
53static LIST_HEAD(regulator_map_list);
54static bool has_full_constraints;
55static bool board_wants_dummy_regulator;
56
57static struct dentry *debugfs_root;
58
59/*
60 * struct regulator_map
61 *
62 * Used to provide symbolic supply names to devices.
63 */
64struct regulator_map {
65	struct list_head list;
66	const char *dev_name;   /* The dev_name() for the consumer */
67	const char *supply;
68	struct regulator_dev *regulator;
69};
70
71/*
72 * struct regulator
73 *
74 * One for each consumer device.
75 */
76struct regulator {
77	struct device *dev;
78	struct list_head list;
79	unsigned int always_on:1;
80	int uA_load;
81	int min_uV;
82	int max_uV;
83	char *supply_name;
84	struct device_attribute dev_attr;
85	struct regulator_dev *rdev;
86	struct dentry *debugfs;
87};
88
89static int _regulator_is_enabled(struct regulator_dev *rdev);
90static int _regulator_disable(struct regulator_dev *rdev);
91static int _regulator_get_voltage(struct regulator_dev *rdev);
92static int _regulator_get_current_limit(struct regulator_dev *rdev);
93static unsigned int _regulator_get_mode(struct regulator_dev *rdev);
94static void _notifier_call_chain(struct regulator_dev *rdev,
95				  unsigned long event, void *data);
96static int _regulator_do_set_voltage(struct regulator_dev *rdev,
97				     int min_uV, int max_uV);
98static struct regulator *create_regulator(struct regulator_dev *rdev,
99					  struct device *dev,
100					  const char *supply_name);
101
102static const char *rdev_get_name(struct regulator_dev *rdev)
103{
104	if (rdev->constraints && rdev->constraints->name)
105		return rdev->constraints->name;
106	else if (rdev->desc->name)
107		return rdev->desc->name;
108	else
109		return "";
110}
111
112/**
113 * of_get_regulator - get a regulator device node based on supply name
114 * @dev: Device pointer for the consumer (of regulator) device
115 * @supply: regulator supply name
116 *
117 * Extract the regulator device node corresponding to the supply name.
118 * retruns the device node corresponding to the regulator if found, else
119 * returns NULL.
120 */
121static struct device_node *of_get_regulator(struct device *dev, const char *supply)
122{
123	struct device_node *regnode = NULL;
124	char prop_name[32]; /* 32 is max size of property name */
125
126	dev_dbg(dev, "Looking up %s-supply from device tree\n", supply);
127
128	snprintf(prop_name, 32, "%s-supply", supply);
129	regnode = of_parse_phandle(dev->of_node, prop_name, 0);
130
131	if (!regnode) {
132		dev_dbg(dev, "Looking up %s property in node %s failed",
133				prop_name, dev->of_node->full_name);
134		return NULL;
135	}
136	return regnode;
137}
138
139static int _regulator_can_change_status(struct regulator_dev *rdev)
140{
141	if (!rdev->constraints)
142		return 0;
143
144	if (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_STATUS)
145		return 1;
146	else
147		return 0;
148}
149
150/* Platform voltage constraint check */
151static int regulator_check_voltage(struct regulator_dev *rdev,
152				   int *min_uV, int *max_uV)
153{
154	BUG_ON(*min_uV > *max_uV);
155
156	if (!rdev->constraints) {
157		rdev_err(rdev, "no constraints\n");
158		return -ENODEV;
159	}
160	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
161		rdev_err(rdev, "operation not allowed\n");
162		return -EPERM;
163	}
164
165	if (*max_uV > rdev->constraints->max_uV)
166		*max_uV = rdev->constraints->max_uV;
167	if (*min_uV < rdev->constraints->min_uV)
168		*min_uV = rdev->constraints->min_uV;
169
170	if (*min_uV > *max_uV) {
171		rdev_err(rdev, "unsupportable voltage range: %d-%duV\n",
172			 *min_uV, *max_uV);
173		return -EINVAL;
174	}
175
176	return 0;
177}
178
179/* Make sure we select a voltage that suits the needs of all
180 * regulator consumers
181 */
182static int regulator_check_consumers(struct regulator_dev *rdev,
183				     int *min_uV, int *max_uV)
184{
185	struct regulator *regulator;
186
187	list_for_each_entry(regulator, &rdev->consumer_list, list) {
188		/*
189		 * Assume consumers that didn't say anything are OK
190		 * with anything in the constraint range.
191		 */
192		if (!regulator->min_uV && !regulator->max_uV)
193			continue;
194
195		if (*max_uV > regulator->max_uV)
196			*max_uV = regulator->max_uV;
197		if (*min_uV < regulator->min_uV)
198			*min_uV = regulator->min_uV;
199	}
200
201	if (*min_uV > *max_uV)
202		return -EINVAL;
203
204	return 0;
205}
206
207/* current constraint check */
208static int regulator_check_current_limit(struct regulator_dev *rdev,
209					int *min_uA, int *max_uA)
210{
211	BUG_ON(*min_uA > *max_uA);
212
213	if (!rdev->constraints) {
214		rdev_err(rdev, "no constraints\n");
215		return -ENODEV;
216	}
217	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_CURRENT)) {
218		rdev_err(rdev, "operation not allowed\n");
219		return -EPERM;
220	}
221
222	if (*max_uA > rdev->constraints->max_uA)
223		*max_uA = rdev->constraints->max_uA;
224	if (*min_uA < rdev->constraints->min_uA)
225		*min_uA = rdev->constraints->min_uA;
226
227	if (*min_uA > *max_uA) {
228		rdev_err(rdev, "unsupportable current range: %d-%duA\n",
229			 *min_uA, *max_uA);
230		return -EINVAL;
231	}
232
233	return 0;
234}
235
236/* operating mode constraint check */
237static int regulator_mode_constrain(struct regulator_dev *rdev, int *mode)
238{
239	switch (*mode) {
240	case REGULATOR_MODE_FAST:
241	case REGULATOR_MODE_NORMAL:
242	case REGULATOR_MODE_IDLE:
243	case REGULATOR_MODE_STANDBY:
244		break;
245	default:
246		rdev_err(rdev, "invalid mode %x specified\n", *mode);
247		return -EINVAL;
248	}
249
250	if (!rdev->constraints) {
251		rdev_err(rdev, "no constraints\n");
252		return -ENODEV;
253	}
254	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_MODE)) {
255		rdev_err(rdev, "operation not allowed\n");
256		return -EPERM;
257	}
258
259	/* The modes are bitmasks, the most power hungry modes having
260	 * the lowest values. If the requested mode isn't supported
261	 * try higher modes. */
262	while (*mode) {
263		if (rdev->constraints->valid_modes_mask & *mode)
264			return 0;
265		*mode /= 2;
266	}
267
268	return -EINVAL;
269}
270
271/* dynamic regulator mode switching constraint check */
272static int regulator_check_drms(struct regulator_dev *rdev)
273{
274	if (!rdev->constraints) {
275		rdev_err(rdev, "no constraints\n");
276		return -ENODEV;
277	}
278	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS)) {
279		rdev_err(rdev, "operation not allowed\n");
280		return -EPERM;
281	}
282	return 0;
283}
284
285static ssize_t regulator_uV_show(struct device *dev,
286				struct device_attribute *attr, char *buf)
287{
288	struct regulator_dev *rdev = dev_get_drvdata(dev);
289	ssize_t ret;
290
291	mutex_lock(&rdev->mutex);
292	ret = sprintf(buf, "%d\n", _regulator_get_voltage(rdev));
293	mutex_unlock(&rdev->mutex);
294
295	return ret;
296}
297static DEVICE_ATTR(microvolts, 0444, regulator_uV_show, NULL);
298
299static ssize_t regulator_uA_show(struct device *dev,
300				struct device_attribute *attr, char *buf)
301{
302	struct regulator_dev *rdev = dev_get_drvdata(dev);
303
304	return sprintf(buf, "%d\n", _regulator_get_current_limit(rdev));
305}
306static DEVICE_ATTR(microamps, 0444, regulator_uA_show, NULL);
307
308static ssize_t regulator_name_show(struct device *dev,
309			     struct device_attribute *attr, char *buf)
310{
311	struct regulator_dev *rdev = dev_get_drvdata(dev);
312
313	return sprintf(buf, "%s\n", rdev_get_name(rdev));
314}
315
316static ssize_t regulator_print_opmode(char *buf, int mode)
317{
318	switch (mode) {
319	case REGULATOR_MODE_FAST:
320		return sprintf(buf, "fast\n");
321	case REGULATOR_MODE_NORMAL:
322		return sprintf(buf, "normal\n");
323	case REGULATOR_MODE_IDLE:
324		return sprintf(buf, "idle\n");
325	case REGULATOR_MODE_STANDBY:
326		return sprintf(buf, "standby\n");
327	}
328	return sprintf(buf, "unknown\n");
329}
330
331static ssize_t regulator_opmode_show(struct device *dev,
332				    struct device_attribute *attr, char *buf)
333{
334	struct regulator_dev *rdev = dev_get_drvdata(dev);
335
336	return regulator_print_opmode(buf, _regulator_get_mode(rdev));
337}
338static DEVICE_ATTR(opmode, 0444, regulator_opmode_show, NULL);
339
340static ssize_t regulator_print_state(char *buf, int state)
341{
342	if (state > 0)
343		return sprintf(buf, "enabled\n");
344	else if (state == 0)
345		return sprintf(buf, "disabled\n");
346	else
347		return sprintf(buf, "unknown\n");
348}
349
350static ssize_t regulator_state_show(struct device *dev,
351				   struct device_attribute *attr, char *buf)
352{
353	struct regulator_dev *rdev = dev_get_drvdata(dev);
354	ssize_t ret;
355
356	mutex_lock(&rdev->mutex);
357	ret = regulator_print_state(buf, _regulator_is_enabled(rdev));
358	mutex_unlock(&rdev->mutex);
359
360	return ret;
361}
362static DEVICE_ATTR(state, 0444, regulator_state_show, NULL);
363
364static ssize_t regulator_status_show(struct device *dev,
365				   struct device_attribute *attr, char *buf)
366{
367	struct regulator_dev *rdev = dev_get_drvdata(dev);
368	int status;
369	char *label;
370
371	status = rdev->desc->ops->get_status(rdev);
372	if (status < 0)
373		return status;
374
375	switch (status) {
376	case REGULATOR_STATUS_OFF:
377		label = "off";
378		break;
379	case REGULATOR_STATUS_ON:
380		label = "on";
381		break;
382	case REGULATOR_STATUS_ERROR:
383		label = "error";
384		break;
385	case REGULATOR_STATUS_FAST:
386		label = "fast";
387		break;
388	case REGULATOR_STATUS_NORMAL:
389		label = "normal";
390		break;
391	case REGULATOR_STATUS_IDLE:
392		label = "idle";
393		break;
394	case REGULATOR_STATUS_STANDBY:
395		label = "standby";
396		break;
397	case REGULATOR_STATUS_UNDEFINED:
398		label = "undefined";
399		break;
400	default:
401		return -ERANGE;
402	}
403
404	return sprintf(buf, "%s\n", label);
405}
406static DEVICE_ATTR(status, 0444, regulator_status_show, NULL);
407
408static ssize_t regulator_min_uA_show(struct device *dev,
409				    struct device_attribute *attr, char *buf)
410{
411	struct regulator_dev *rdev = dev_get_drvdata(dev);
412
413	if (!rdev->constraints)
414		return sprintf(buf, "constraint not defined\n");
415
416	return sprintf(buf, "%d\n", rdev->constraints->min_uA);
417}
418static DEVICE_ATTR(min_microamps, 0444, regulator_min_uA_show, NULL);
419
420static ssize_t regulator_max_uA_show(struct device *dev,
421				    struct device_attribute *attr, char *buf)
422{
423	struct regulator_dev *rdev = dev_get_drvdata(dev);
424
425	if (!rdev->constraints)
426		return sprintf(buf, "constraint not defined\n");
427
428	return sprintf(buf, "%d\n", rdev->constraints->max_uA);
429}
430static DEVICE_ATTR(max_microamps, 0444, regulator_max_uA_show, NULL);
431
432static ssize_t regulator_min_uV_show(struct device *dev,
433				    struct device_attribute *attr, char *buf)
434{
435	struct regulator_dev *rdev = dev_get_drvdata(dev);
436
437	if (!rdev->constraints)
438		return sprintf(buf, "constraint not defined\n");
439
440	return sprintf(buf, "%d\n", rdev->constraints->min_uV);
441}
442static DEVICE_ATTR(min_microvolts, 0444, regulator_min_uV_show, NULL);
443
444static ssize_t regulator_max_uV_show(struct device *dev,
445				    struct device_attribute *attr, char *buf)
446{
447	struct regulator_dev *rdev = dev_get_drvdata(dev);
448
449	if (!rdev->constraints)
450		return sprintf(buf, "constraint not defined\n");
451
452	return sprintf(buf, "%d\n", rdev->constraints->max_uV);
453}
454static DEVICE_ATTR(max_microvolts, 0444, regulator_max_uV_show, NULL);
455
456static ssize_t regulator_total_uA_show(struct device *dev,
457				      struct device_attribute *attr, char *buf)
458{
459	struct regulator_dev *rdev = dev_get_drvdata(dev);
460	struct regulator *regulator;
461	int uA = 0;
462
463	mutex_lock(&rdev->mutex);
464	list_for_each_entry(regulator, &rdev->consumer_list, list)
465		uA += regulator->uA_load;
466	mutex_unlock(&rdev->mutex);
467	return sprintf(buf, "%d\n", uA);
468}
469static DEVICE_ATTR(requested_microamps, 0444, regulator_total_uA_show, NULL);
470
471static ssize_t regulator_num_users_show(struct device *dev,
472				      struct device_attribute *attr, char *buf)
473{
474	struct regulator_dev *rdev = dev_get_drvdata(dev);
475	return sprintf(buf, "%d\n", rdev->use_count);
476}
477
478static ssize_t regulator_type_show(struct device *dev,
479				  struct device_attribute *attr, char *buf)
480{
481	struct regulator_dev *rdev = dev_get_drvdata(dev);
482
483	switch (rdev->desc->type) {
484	case REGULATOR_VOLTAGE:
485		return sprintf(buf, "voltage\n");
486	case REGULATOR_CURRENT:
487		return sprintf(buf, "current\n");
488	}
489	return sprintf(buf, "unknown\n");
490}
491
492static ssize_t regulator_suspend_mem_uV_show(struct device *dev,
493				struct device_attribute *attr, char *buf)
494{
495	struct regulator_dev *rdev = dev_get_drvdata(dev);
496
497	return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
498}
499static DEVICE_ATTR(suspend_mem_microvolts, 0444,
500		regulator_suspend_mem_uV_show, NULL);
501
502static ssize_t regulator_suspend_disk_uV_show(struct device *dev,
503				struct device_attribute *attr, char *buf)
504{
505	struct regulator_dev *rdev = dev_get_drvdata(dev);
506
507	return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
508}
509static DEVICE_ATTR(suspend_disk_microvolts, 0444,
510		regulator_suspend_disk_uV_show, NULL);
511
512static ssize_t regulator_suspend_standby_uV_show(struct device *dev,
513				struct device_attribute *attr, char *buf)
514{
515	struct regulator_dev *rdev = dev_get_drvdata(dev);
516
517	return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
518}
519static DEVICE_ATTR(suspend_standby_microvolts, 0444,
520		regulator_suspend_standby_uV_show, NULL);
521
522static ssize_t regulator_suspend_mem_mode_show(struct device *dev,
523				struct device_attribute *attr, char *buf)
524{
525	struct regulator_dev *rdev = dev_get_drvdata(dev);
526
527	return regulator_print_opmode(buf,
528		rdev->constraints->state_mem.mode);
529}
530static DEVICE_ATTR(suspend_mem_mode, 0444,
531		regulator_suspend_mem_mode_show, NULL);
532
533static ssize_t regulator_suspend_disk_mode_show(struct device *dev,
534				struct device_attribute *attr, char *buf)
535{
536	struct regulator_dev *rdev = dev_get_drvdata(dev);
537
538	return regulator_print_opmode(buf,
539		rdev->constraints->state_disk.mode);
540}
541static DEVICE_ATTR(suspend_disk_mode, 0444,
542		regulator_suspend_disk_mode_show, NULL);
543
544static ssize_t regulator_suspend_standby_mode_show(struct device *dev,
545				struct device_attribute *attr, char *buf)
546{
547	struct regulator_dev *rdev = dev_get_drvdata(dev);
548
549	return regulator_print_opmode(buf,
550		rdev->constraints->state_standby.mode);
551}
552static DEVICE_ATTR(suspend_standby_mode, 0444,
553		regulator_suspend_standby_mode_show, NULL);
554
555static ssize_t regulator_suspend_mem_state_show(struct device *dev,
556				   struct device_attribute *attr, char *buf)
557{
558	struct regulator_dev *rdev = dev_get_drvdata(dev);
559
560	return regulator_print_state(buf,
561			rdev->constraints->state_mem.enabled);
562}
563static DEVICE_ATTR(suspend_mem_state, 0444,
564		regulator_suspend_mem_state_show, NULL);
565
566static ssize_t regulator_suspend_disk_state_show(struct device *dev,
567				   struct device_attribute *attr, char *buf)
568{
569	struct regulator_dev *rdev = dev_get_drvdata(dev);
570
571	return regulator_print_state(buf,
572			rdev->constraints->state_disk.enabled);
573}
574static DEVICE_ATTR(suspend_disk_state, 0444,
575		regulator_suspend_disk_state_show, NULL);
576
577static ssize_t regulator_suspend_standby_state_show(struct device *dev,
578				   struct device_attribute *attr, char *buf)
579{
580	struct regulator_dev *rdev = dev_get_drvdata(dev);
581
582	return regulator_print_state(buf,
583			rdev->constraints->state_standby.enabled);
584}
585static DEVICE_ATTR(suspend_standby_state, 0444,
586		regulator_suspend_standby_state_show, NULL);
587
588
589/*
590 * These are the only attributes are present for all regulators.
591 * Other attributes are a function of regulator functionality.
592 */
593static struct device_attribute regulator_dev_attrs[] = {
594	__ATTR(name, 0444, regulator_name_show, NULL),
595	__ATTR(num_users, 0444, regulator_num_users_show, NULL),
596	__ATTR(type, 0444, regulator_type_show, NULL),
597	__ATTR_NULL,
598};
599
600static void regulator_dev_release(struct device *dev)
601{
602	struct regulator_dev *rdev = dev_get_drvdata(dev);
603	kfree(rdev);
604}
605
606static struct class regulator_class = {
607	.name = "regulator",
608	.dev_release = regulator_dev_release,
609	.dev_attrs = regulator_dev_attrs,
610};
611
612/* Calculate the new optimum regulator operating mode based on the new total
613 * consumer load. All locks held by caller */
614static void drms_uA_update(struct regulator_dev *rdev)
615{
616	struct regulator *sibling;
617	int current_uA = 0, output_uV, input_uV, err;
618	unsigned int mode;
619
620	err = regulator_check_drms(rdev);
621	if (err < 0 || !rdev->desc->ops->get_optimum_mode ||
622	    (!rdev->desc->ops->get_voltage &&
623	     !rdev->desc->ops->get_voltage_sel) ||
624	    !rdev->desc->ops->set_mode)
625		return;
626
627	/* get output voltage */
628	output_uV = _regulator_get_voltage(rdev);
629	if (output_uV <= 0)
630		return;
631
632	/* get input voltage */
633	input_uV = 0;
634	if (rdev->supply)
635		input_uV = regulator_get_voltage(rdev->supply);
636	if (input_uV <= 0)
637		input_uV = rdev->constraints->input_uV;
638	if (input_uV <= 0)
639		return;
640
641	/* calc total requested load */
642	list_for_each_entry(sibling, &rdev->consumer_list, list)
643		current_uA += sibling->uA_load;
644
645	/* now get the optimum mode for our new total regulator load */
646	mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
647						  output_uV, current_uA);
648
649	/* check the new mode is allowed */
650	err = regulator_mode_constrain(rdev, &mode);
651	if (err == 0)
652		rdev->desc->ops->set_mode(rdev, mode);
653}
654
655static int suspend_set_state(struct regulator_dev *rdev,
656	struct regulator_state *rstate)
657{
658	int ret = 0;
659
660	/* If we have no suspend mode configration don't set anything;
661	 * only warn if the driver implements set_suspend_voltage or
662	 * set_suspend_mode callback.
663	 */
664	if (!rstate->enabled && !rstate->disabled) {
665		if (rdev->desc->ops->set_suspend_voltage ||
666		    rdev->desc->ops->set_suspend_mode)
667			rdev_warn(rdev, "No configuration\n");
668		return 0;
669	}
670
671	if (rstate->enabled && rstate->disabled) {
672		rdev_err(rdev, "invalid configuration\n");
673		return -EINVAL;
674	}
675
676	if (rstate->enabled && rdev->desc->ops->set_suspend_enable)
677		ret = rdev->desc->ops->set_suspend_enable(rdev);
678	else if (rstate->disabled && rdev->desc->ops->set_suspend_disable)
679		ret = rdev->desc->ops->set_suspend_disable(rdev);
680	else /* OK if set_suspend_enable or set_suspend_disable is NULL */
681		ret = 0;
682
683	if (ret < 0) {
684		rdev_err(rdev, "failed to enabled/disable\n");
685		return ret;
686	}
687
688	if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
689		ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
690		if (ret < 0) {
691			rdev_err(rdev, "failed to set voltage\n");
692			return ret;
693		}
694	}
695
696	if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
697		ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
698		if (ret < 0) {
699			rdev_err(rdev, "failed to set mode\n");
700			return ret;
701		}
702	}
703	return ret;
704}
705
706/* locks held by caller */
707static int suspend_prepare(struct regulator_dev *rdev, suspend_state_t state)
708{
709	if (!rdev->constraints)
710		return -EINVAL;
711
712	switch (state) {
713	case PM_SUSPEND_STANDBY:
714		return suspend_set_state(rdev,
715			&rdev->constraints->state_standby);
716	case PM_SUSPEND_MEM:
717		return suspend_set_state(rdev,
718			&rdev->constraints->state_mem);
719	case PM_SUSPEND_MAX:
720		return suspend_set_state(rdev,
721			&rdev->constraints->state_disk);
722	default:
723		return -EINVAL;
724	}
725}
726
727static void print_constraints(struct regulator_dev *rdev)
728{
729	struct regulation_constraints *constraints = rdev->constraints;
730	char buf[80] = "";
731	int count = 0;
732	int ret;
733
734	if (constraints->min_uV && constraints->max_uV) {
735		if (constraints->min_uV == constraints->max_uV)
736			count += sprintf(buf + count, "%d mV ",
737					 constraints->min_uV / 1000);
738		else
739			count += sprintf(buf + count, "%d <--> %d mV ",
740					 constraints->min_uV / 1000,
741					 constraints->max_uV / 1000);
742	}
743
744	if (!constraints->min_uV ||
745	    constraints->min_uV != constraints->max_uV) {
746		ret = _regulator_get_voltage(rdev);
747		if (ret > 0)
748			count += sprintf(buf + count, "at %d mV ", ret / 1000);
749	}
750
751	if (constraints->uV_offset)
752		count += sprintf(buf, "%dmV offset ",
753				 constraints->uV_offset / 1000);
754
755	if (constraints->min_uA && constraints->max_uA) {
756		if (constraints->min_uA == constraints->max_uA)
757			count += sprintf(buf + count, "%d mA ",
758					 constraints->min_uA / 1000);
759		else
760			count += sprintf(buf + count, "%d <--> %d mA ",
761					 constraints->min_uA / 1000,
762					 constraints->max_uA / 1000);
763	}
764
765	if (!constraints->min_uA ||
766	    constraints->min_uA != constraints->max_uA) {
767		ret = _regulator_get_current_limit(rdev);
768		if (ret > 0)
769			count += sprintf(buf + count, "at %d mA ", ret / 1000);
770	}
771
772	if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
773		count += sprintf(buf + count, "fast ");
774	if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
775		count += sprintf(buf + count, "normal ");
776	if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
777		count += sprintf(buf + count, "idle ");
778	if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
779		count += sprintf(buf + count, "standby");
780
781	if (!count)
782		sprintf(buf, "no parameters");
783
784	rdev_info(rdev, "%s\n", buf);
785
786	if ((constraints->min_uV != constraints->max_uV) &&
787	    !(constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE))
788		rdev_warn(rdev,
789			  "Voltage range but no REGULATOR_CHANGE_VOLTAGE\n");
790}
791
792static int machine_constraints_voltage(struct regulator_dev *rdev,
793	struct regulation_constraints *constraints)
794{
795	struct regulator_ops *ops = rdev->desc->ops;
796	int ret;
797
798	/* do we need to apply the constraint voltage */
799	if (rdev->constraints->apply_uV &&
800	    rdev->constraints->min_uV == rdev->constraints->max_uV) {
801		ret = _regulator_do_set_voltage(rdev,
802						rdev->constraints->min_uV,
803						rdev->constraints->max_uV);
804		if (ret < 0) {
805			rdev_err(rdev, "failed to apply %duV constraint\n",
806				 rdev->constraints->min_uV);
807			return ret;
808		}
809	}
810
811	/* constrain machine-level voltage specs to fit
812	 * the actual range supported by this regulator.
813	 */
814	if (ops->list_voltage && rdev->desc->n_voltages) {
815		int	count = rdev->desc->n_voltages;
816		int	i;
817		int	min_uV = INT_MAX;
818		int	max_uV = INT_MIN;
819		int	cmin = constraints->min_uV;
820		int	cmax = constraints->max_uV;
821
822		/* it's safe to autoconfigure fixed-voltage supplies
823		   and the constraints are used by list_voltage. */
824		if (count == 1 && !cmin) {
825			cmin = 1;
826			cmax = INT_MAX;
827			constraints->min_uV = cmin;
828			constraints->max_uV = cmax;
829		}
830
831		/* voltage constraints are optional */
832		if ((cmin == 0) && (cmax == 0))
833			return 0;
834
835		/* else require explicit machine-level constraints */
836		if (cmin <= 0 || cmax <= 0 || cmax < cmin) {
837			rdev_err(rdev, "invalid voltage constraints\n");
838			return -EINVAL;
839		}
840
841		/* initial: [cmin..cmax] valid, [min_uV..max_uV] not */
842		for (i = 0; i < count; i++) {
843			int	value;
844
845			value = ops->list_voltage(rdev, i);
846			if (value <= 0)
847				continue;
848
849			/* maybe adjust [min_uV..max_uV] */
850			if (value >= cmin && value < min_uV)
851				min_uV = value;
852			if (value <= cmax && value > max_uV)
853				max_uV = value;
854		}
855
856		/* final: [min_uV..max_uV] valid iff constraints valid */
857		if (max_uV < min_uV) {
858			rdev_err(rdev, "unsupportable voltage constraints\n");
859			return -EINVAL;
860		}
861
862		/* use regulator's subset of machine constraints */
863		if (constraints->min_uV < min_uV) {
864			rdev_dbg(rdev, "override min_uV, %d -> %d\n",
865				 constraints->min_uV, min_uV);
866			constraints->min_uV = min_uV;
867		}
868		if (constraints->max_uV > max_uV) {
869			rdev_dbg(rdev, "override max_uV, %d -> %d\n",
870				 constraints->max_uV, max_uV);
871			constraints->max_uV = max_uV;
872		}
873	}
874
875	return 0;
876}
877
878/**
879 * set_machine_constraints - sets regulator constraints
880 * @rdev: regulator source
881 * @constraints: constraints to apply
882 *
883 * Allows platform initialisation code to define and constrain
884 * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
885 * Constraints *must* be set by platform code in order for some
886 * regulator operations to proceed i.e. set_voltage, set_current_limit,
887 * set_mode.
888 */
889static int set_machine_constraints(struct regulator_dev *rdev,
890	const struct regulation_constraints *constraints)
891{
892	int ret = 0;
893	struct regulator_ops *ops = rdev->desc->ops;
894
895	if (constraints)
896		rdev->constraints = kmemdup(constraints, sizeof(*constraints),
897					    GFP_KERNEL);
898	else
899		rdev->constraints = kzalloc(sizeof(*constraints),
900					    GFP_KERNEL);
901	if (!rdev->constraints)
902		return -ENOMEM;
903
904	ret = machine_constraints_voltage(rdev, rdev->constraints);
905	if (ret != 0)
906		goto out;
907
908	/* do we need to setup our suspend state */
909	if (rdev->constraints->initial_state) {
910		ret = suspend_prepare(rdev, rdev->constraints->initial_state);
911		if (ret < 0) {
912			rdev_err(rdev, "failed to set suspend state\n");
913			goto out;
914		}
915	}
916
917	if (rdev->constraints->initial_mode) {
918		if (!ops->set_mode) {
919			rdev_err(rdev, "no set_mode operation\n");
920			ret = -EINVAL;
921			goto out;
922		}
923
924		ret = ops->set_mode(rdev, rdev->constraints->initial_mode);
925		if (ret < 0) {
926			rdev_err(rdev, "failed to set initial mode: %d\n", ret);
927			goto out;
928		}
929	}
930
931	/* If the constraints say the regulator should be on at this point
932	 * and we have control then make sure it is enabled.
933	 */
934	if ((rdev->constraints->always_on || rdev->constraints->boot_on) &&
935	    ops->enable) {
936		ret = ops->enable(rdev);
937		if (ret < 0) {
938			rdev_err(rdev, "failed to enable\n");
939			goto out;
940		}
941	}
942
943	if (rdev->constraints->ramp_delay && ops->set_ramp_delay) {
944		ret = ops->set_ramp_delay(rdev, rdev->constraints->ramp_delay);
945		if (ret < 0) {
946			rdev_err(rdev, "failed to set ramp_delay\n");
947			goto out;
948		}
949	}
950
951	print_constraints(rdev);
952	return 0;
953out:
954	kfree(rdev->constraints);
955	rdev->constraints = NULL;
956	return ret;
957}
958
959/**
960 * set_supply - set regulator supply regulator
961 * @rdev: regulator name
962 * @supply_rdev: supply regulator name
963 *
964 * Called by platform initialisation code to set the supply regulator for this
965 * regulator. This ensures that a regulators supply will also be enabled by the
966 * core if it's child is enabled.
967 */
968static int set_supply(struct regulator_dev *rdev,
969		      struct regulator_dev *supply_rdev)
970{
971	int err;
972
973	rdev_info(rdev, "supplied by %s\n", rdev_get_name(supply_rdev));
974
975	rdev->supply = create_regulator(supply_rdev, &rdev->dev, "SUPPLY");
976	if (rdev->supply == NULL) {
977		err = -ENOMEM;
978		return err;
979	}
980	supply_rdev->open_count++;
981
982	return 0;
983}
984
985/**
986 * set_consumer_device_supply - Bind a regulator to a symbolic supply
987 * @rdev:         regulator source
988 * @consumer_dev_name: dev_name() string for device supply applies to
989 * @supply:       symbolic name for supply
990 *
991 * Allows platform initialisation code to map physical regulator
992 * sources to symbolic names for supplies for use by devices.  Devices
993 * should use these symbolic names to request regulators, avoiding the
994 * need to provide board-specific regulator names as platform data.
995 */
996static int set_consumer_device_supply(struct regulator_dev *rdev,
997				      const char *consumer_dev_name,
998				      const char *supply)
999{
1000	struct regulator_map *node;
1001	int has_dev;
1002
1003	if (supply == NULL)
1004		return -EINVAL;
1005
1006	if (consumer_dev_name != NULL)
1007		has_dev = 1;
1008	else
1009		has_dev = 0;
1010
1011	list_for_each_entry(node, &regulator_map_list, list) {
1012		if (node->dev_name && consumer_dev_name) {
1013			if (strcmp(node->dev_name, consumer_dev_name) != 0)
1014				continue;
1015		} else if (node->dev_name || consumer_dev_name) {
1016			continue;
1017		}
1018
1019		if (strcmp(node->supply, supply) != 0)
1020			continue;
1021
1022		pr_debug("%s: %s/%s is '%s' supply; fail %s/%s\n",
1023			 consumer_dev_name,
1024			 dev_name(&node->regulator->dev),
1025			 node->regulator->desc->name,
1026			 supply,
1027			 dev_name(&rdev->dev), rdev_get_name(rdev));
1028		return -EBUSY;
1029	}
1030
1031	node = kzalloc(sizeof(struct regulator_map), GFP_KERNEL);
1032	if (node == NULL)
1033		return -ENOMEM;
1034
1035	node->regulator = rdev;
1036	node->supply = supply;
1037
1038	if (has_dev) {
1039		node->dev_name = kstrdup(consumer_dev_name, GFP_KERNEL);
1040		if (node->dev_name == NULL) {
1041			kfree(node);
1042			return -ENOMEM;
1043		}
1044	}
1045
1046	list_add(&node->list, &regulator_map_list);
1047	return 0;
1048}
1049
1050static void unset_regulator_supplies(struct regulator_dev *rdev)
1051{
1052	struct regulator_map *node, *n;
1053
1054	list_for_each_entry_safe(node, n, &regulator_map_list, list) {
1055		if (rdev == node->regulator) {
1056			list_del(&node->list);
1057			kfree(node->dev_name);
1058			kfree(node);
1059		}
1060	}
1061}
1062
1063#define REG_STR_SIZE	64
1064
1065static struct regulator *create_regulator(struct regulator_dev *rdev,
1066					  struct device *dev,
1067					  const char *supply_name)
1068{
1069	struct regulator *regulator;
1070	char buf[REG_STR_SIZE];
1071	int err, size;
1072
1073	regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
1074	if (regulator == NULL)
1075		return NULL;
1076
1077	mutex_lock(&rdev->mutex);
1078	regulator->rdev = rdev;
1079	list_add(&regulator->list, &rdev->consumer_list);
1080
1081	if (dev) {
1082		regulator->dev = dev;
1083
1084		/* Add a link to the device sysfs entry */
1085		size = scnprintf(buf, REG_STR_SIZE, "%s-%s",
1086				 dev->kobj.name, supply_name);
1087		if (size >= REG_STR_SIZE)
1088			goto overflow_err;
1089
1090		regulator->supply_name = kstrdup(buf, GFP_KERNEL);
1091		if (regulator->supply_name == NULL)
1092			goto overflow_err;
1093
1094		err = sysfs_create_link(&rdev->dev.kobj, &dev->kobj,
1095					buf);
1096		if (err) {
1097			rdev_warn(rdev, "could not add device link %s err %d\n",
1098				  dev->kobj.name, err);
1099			/* non-fatal */
1100		}
1101	} else {
1102		regulator->supply_name = kstrdup(supply_name, GFP_KERNEL);
1103		if (regulator->supply_name == NULL)
1104			goto overflow_err;
1105	}
1106
1107	regulator->debugfs = debugfs_create_dir(regulator->supply_name,
1108						rdev->debugfs);
1109	if (!regulator->debugfs) {
1110		rdev_warn(rdev, "Failed to create debugfs directory\n");
1111	} else {
1112		debugfs_create_u32("uA_load", 0444, regulator->debugfs,
1113				   &regulator->uA_load);
1114		debugfs_create_u32("min_uV", 0444, regulator->debugfs,
1115				   &regulator->min_uV);
1116		debugfs_create_u32("max_uV", 0444, regulator->debugfs,
1117				   &regulator->max_uV);
1118	}
1119
1120	/*
1121	 * Check now if the regulator is an always on regulator - if
1122	 * it is then we don't need to do nearly so much work for
1123	 * enable/disable calls.
1124	 */
1125	if (!_regulator_can_change_status(rdev) &&
1126	    _regulator_is_enabled(rdev))
1127		regulator->always_on = true;
1128
1129	mutex_unlock(&rdev->mutex);
1130	return regulator;
1131overflow_err:
1132	list_del(&regulator->list);
1133	kfree(regulator);
1134	mutex_unlock(&rdev->mutex);
1135	return NULL;
1136}
1137
1138static int _regulator_get_enable_time(struct regulator_dev *rdev)
1139{
1140	if (!rdev->desc->ops->enable_time)
1141		return rdev->desc->enable_time;
1142	return rdev->desc->ops->enable_time(rdev);
1143}
1144
1145static struct regulator_dev *regulator_dev_lookup(struct device *dev,
1146						  const char *supply,
1147						  int *ret)
1148{
1149	struct regulator_dev *r;
1150	struct device_node *node;
1151	struct regulator_map *map;
1152	const char *devname = NULL;
1153
1154	/* first do a dt based lookup */
1155	if (dev && dev->of_node) {
1156		node = of_get_regulator(dev, supply);
1157		if (node) {
1158			list_for_each_entry(r, &regulator_list, list)
1159				if (r->dev.parent &&
1160					node == r->dev.of_node)
1161					return r;
1162		} else {
1163			/*
1164			 * If we couldn't even get the node then it's
1165			 * not just that the device didn't register
1166			 * yet, there's no node and we'll never
1167			 * succeed.
1168			 */
1169			*ret = -ENODEV;
1170		}
1171	}
1172
1173	/* if not found, try doing it non-dt way */
1174	if (dev)
1175		devname = dev_name(dev);
1176
1177	list_for_each_entry(r, &regulator_list, list)
1178		if (strcmp(rdev_get_name(r), supply) == 0)
1179			return r;
1180
1181	list_for_each_entry(map, &regulator_map_list, list) {
1182		/* If the mapping has a device set up it must match */
1183		if (map->dev_name &&
1184		    (!devname || strcmp(map->dev_name, devname)))
1185			continue;
1186
1187		if (strcmp(map->supply, supply) == 0)
1188			return map->regulator;
1189	}
1190
1191
1192	return NULL;
1193}
1194
1195/* Internal regulator request function */
1196static struct regulator *_regulator_get(struct device *dev, const char *id,
1197					int exclusive)
1198{
1199	struct regulator_dev *rdev;
1200	struct regulator *regulator = ERR_PTR(-EPROBE_DEFER);
1201	const char *devname = NULL;
1202	int ret;
1203
1204	if (id == NULL) {
1205		pr_err("get() with no identifier\n");
1206		return regulator;
1207	}
1208
1209	if (dev)
1210		devname = dev_name(dev);
1211
1212	mutex_lock(&regulator_list_mutex);
1213
1214	rdev = regulator_dev_lookup(dev, id, &ret);
1215	if (rdev)
1216		goto found;
1217
1218	if (board_wants_dummy_regulator) {
1219		rdev = dummy_regulator_rdev;
1220		goto found;
1221	}
1222
1223#ifdef CONFIG_REGULATOR_DUMMY
1224	if (!devname)
1225		devname = "deviceless";
1226
1227	/* If the board didn't flag that it was fully constrained then
1228	 * substitute in a dummy regulator so consumers can continue.
1229	 */
1230	if (!has_full_constraints) {
1231		pr_warn("%s supply %s not found, using dummy regulator\n",
1232			devname, id);
1233		rdev = dummy_regulator_rdev;
1234		goto found;
1235	}
1236#endif
1237
1238	mutex_unlock(&regulator_list_mutex);
1239	return regulator;
1240
1241found:
1242	if (rdev->exclusive) {
1243		regulator = ERR_PTR(-EPERM);
1244		goto out;
1245	}
1246
1247	if (exclusive && rdev->open_count) {
1248		regulator = ERR_PTR(-EBUSY);
1249		goto out;
1250	}
1251
1252	if (!try_module_get(rdev->owner))
1253		goto out;
1254
1255	regulator = create_regulator(rdev, dev, id);
1256	if (regulator == NULL) {
1257		regulator = ERR_PTR(-ENOMEM);
1258		module_put(rdev->owner);
1259		goto out;
1260	}
1261
1262	rdev->open_count++;
1263	if (exclusive) {
1264		rdev->exclusive = 1;
1265
1266		ret = _regulator_is_enabled(rdev);
1267		if (ret > 0)
1268			rdev->use_count = 1;
1269		else
1270			rdev->use_count = 0;
1271	}
1272
1273out:
1274	mutex_unlock(&regulator_list_mutex);
1275
1276	return regulator;
1277}
1278
1279/**
1280 * regulator_get - lookup and obtain a reference to a regulator.
1281 * @dev: device for regulator "consumer"
1282 * @id: Supply name or regulator ID.
1283 *
1284 * Returns a struct regulator corresponding to the regulator producer,
1285 * or IS_ERR() condition containing errno.
1286 *
1287 * Use of supply names configured via regulator_set_device_supply() is
1288 * strongly encouraged.  It is recommended that the supply name used
1289 * should match the name used for the supply and/or the relevant
1290 * device pins in the datasheet.
1291 */
1292struct regulator *regulator_get(struct device *dev, const char *id)
1293{
1294	return _regulator_get(dev, id, 0);
1295}
1296EXPORT_SYMBOL_GPL(regulator_get);
1297
1298static void devm_regulator_release(struct device *dev, void *res)
1299{
1300	regulator_put(*(struct regulator **)res);
1301}
1302
1303/**
1304 * devm_regulator_get - Resource managed regulator_get()
1305 * @dev: device for regulator "consumer"
1306 * @id: Supply name or regulator ID.
1307 *
1308 * Managed regulator_get(). Regulators returned from this function are
1309 * automatically regulator_put() on driver detach. See regulator_get() for more
1310 * information.
1311 */
1312struct regulator *devm_regulator_get(struct device *dev, const char *id)
1313{
1314	struct regulator **ptr, *regulator;
1315
1316	ptr = devres_alloc(devm_regulator_release, sizeof(*ptr), GFP_KERNEL);
1317	if (!ptr)
1318		return ERR_PTR(-ENOMEM);
1319
1320	regulator = regulator_get(dev, id);
1321	if (!IS_ERR(regulator)) {
1322		*ptr = regulator;
1323		devres_add(dev, ptr);
1324	} else {
1325		devres_free(ptr);
1326	}
1327
1328	return regulator;
1329}
1330EXPORT_SYMBOL_GPL(devm_regulator_get);
1331
1332/**
1333 * regulator_get_exclusive - obtain exclusive access to a regulator.
1334 * @dev: device for regulator "consumer"
1335 * @id: Supply name or regulator ID.
1336 *
1337 * Returns a struct regulator corresponding to the regulator producer,
1338 * or IS_ERR() condition containing errno.  Other consumers will be
1339 * unable to obtain this reference is held and the use count for the
1340 * regulator will be initialised to reflect the current state of the
1341 * regulator.
1342 *
1343 * This is intended for use by consumers which cannot tolerate shared
1344 * use of the regulator such as those which need to force the
1345 * regulator off for correct operation of the hardware they are
1346 * controlling.
1347 *
1348 * Use of supply names configured via regulator_set_device_supply() is
1349 * strongly encouraged.  It is recommended that the supply name used
1350 * should match the name used for the supply and/or the relevant
1351 * device pins in the datasheet.
1352 */
1353struct regulator *regulator_get_exclusive(struct device *dev, const char *id)
1354{
1355	return _regulator_get(dev, id, 1);
1356}
1357EXPORT_SYMBOL_GPL(regulator_get_exclusive);
1358
1359/**
1360 * regulator_put - "free" the regulator source
1361 * @regulator: regulator source
1362 *
1363 * Note: drivers must ensure that all regulator_enable calls made on this
1364 * regulator source are balanced by regulator_disable calls prior to calling
1365 * this function.
1366 */
1367void regulator_put(struct regulator *regulator)
1368{
1369	struct regulator_dev *rdev;
1370
1371	if (regulator == NULL || IS_ERR(regulator))
1372		return;
1373
1374	mutex_lock(&regulator_list_mutex);
1375	rdev = regulator->rdev;
1376
1377	debugfs_remove_recursive(regulator->debugfs);
1378
1379	/* remove any sysfs entries */
1380	if (regulator->dev)
1381		sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
1382	kfree(regulator->supply_name);
1383	list_del(&regulator->list);
1384	kfree(regulator);
1385
1386	rdev->open_count--;
1387	rdev->exclusive = 0;
1388
1389	module_put(rdev->owner);
1390	mutex_unlock(&regulator_list_mutex);
1391}
1392EXPORT_SYMBOL_GPL(regulator_put);
1393
1394static int devm_regulator_match(struct device *dev, void *res, void *data)
1395{
1396	struct regulator **r = res;
1397	if (!r || !*r) {
1398		WARN_ON(!r || !*r);
1399		return 0;
1400	}
1401	return *r == data;
1402}
1403
1404/**
1405 * devm_regulator_put - Resource managed regulator_put()
1406 * @regulator: regulator to free
1407 *
1408 * Deallocate a regulator allocated with devm_regulator_get(). Normally
1409 * this function will not need to be called and the resource management
1410 * code will ensure that the resource is freed.
1411 */
1412void devm_regulator_put(struct regulator *regulator)
1413{
1414	int rc;
1415
1416	rc = devres_release(regulator->dev, devm_regulator_release,
1417			    devm_regulator_match, regulator);
1418	if (rc != 0)
1419		WARN_ON(rc);
1420}
1421EXPORT_SYMBOL_GPL(devm_regulator_put);
1422
1423static int _regulator_do_enable(struct regulator_dev *rdev)
1424{
1425	int ret, delay;
1426
1427	/* Query before enabling in case configuration dependent.  */
1428	ret = _regulator_get_enable_time(rdev);
1429	if (ret >= 0) {
1430		delay = ret;
1431	} else {
1432		rdev_warn(rdev, "enable_time() failed: %d\n", ret);
1433		delay = 0;
1434	}
1435
1436	trace_regulator_enable(rdev_get_name(rdev));
1437
1438	if (rdev->ena_gpio) {
1439		gpio_set_value_cansleep(rdev->ena_gpio,
1440					!rdev->ena_gpio_invert);
1441		rdev->ena_gpio_state = 1;
1442	} else if (rdev->desc->ops->enable) {
1443		ret = rdev->desc->ops->enable(rdev);
1444		if (ret < 0)
1445			return ret;
1446	} else {
1447		return -EINVAL;
1448	}
1449
1450	/* Allow the regulator to ramp; it would be useful to extend
1451	 * this for bulk operations so that the regulators can ramp
1452	 * together.  */
1453	trace_regulator_enable_delay(rdev_get_name(rdev));
1454
1455	if (delay >= 1000) {
1456		mdelay(delay / 1000);
1457		udelay(delay % 1000);
1458	} else if (delay) {
1459		udelay(delay);
1460	}
1461
1462	trace_regulator_enable_complete(rdev_get_name(rdev));
1463
1464	return 0;
1465}
1466
1467/* locks held by regulator_enable() */
1468static int _regulator_enable(struct regulator_dev *rdev)
1469{
1470	int ret;
1471
1472	/* check voltage and requested load before enabling */
1473	if (rdev->constraints &&
1474	    (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS))
1475		drms_uA_update(rdev);
1476
1477	if (rdev->use_count == 0) {
1478		/* The regulator may on if it's not switchable or left on */
1479		ret = _regulator_is_enabled(rdev);
1480		if (ret == -EINVAL || ret == 0) {
1481			if (!_regulator_can_change_status(rdev))
1482				return -EPERM;
1483
1484			ret = _regulator_do_enable(rdev);
1485			if (ret < 0)
1486				return ret;
1487
1488		} else if (ret < 0) {
1489			rdev_err(rdev, "is_enabled() failed: %d\n", ret);
1490			return ret;
1491		}
1492		/* Fallthrough on positive return values - already enabled */
1493	}
1494
1495	rdev->use_count++;
1496
1497	return 0;
1498}
1499
1500/**
1501 * regulator_enable - enable regulator output
1502 * @regulator: regulator source
1503 *
1504 * Request that the regulator be enabled with the regulator output at
1505 * the predefined voltage or current value.  Calls to regulator_enable()
1506 * must be balanced with calls to regulator_disable().
1507 *
1508 * NOTE: the output value can be set by other drivers, boot loader or may be
1509 * hardwired in the regulator.
1510 */
1511int regulator_enable(struct regulator *regulator)
1512{
1513	struct regulator_dev *rdev = regulator->rdev;
1514	int ret = 0;
1515
1516	if (regulator->always_on)
1517		return 0;
1518
1519	if (rdev->supply) {
1520		ret = regulator_enable(rdev->supply);
1521		if (ret != 0)
1522			return ret;
1523	}
1524
1525	mutex_lock(&rdev->mutex);
1526	ret = _regulator_enable(rdev);
1527	mutex_unlock(&rdev->mutex);
1528
1529	if (ret != 0 && rdev->supply)
1530		regulator_disable(rdev->supply);
1531
1532	return ret;
1533}
1534EXPORT_SYMBOL_GPL(regulator_enable);
1535
1536static int _regulator_do_disable(struct regulator_dev *rdev)
1537{
1538	int ret;
1539
1540	trace_regulator_disable(rdev_get_name(rdev));
1541
1542	if (rdev->ena_gpio) {
1543		gpio_set_value_cansleep(rdev->ena_gpio,
1544					rdev->ena_gpio_invert);
1545		rdev->ena_gpio_state = 0;
1546
1547	} else if (rdev->desc->ops->disable) {
1548		ret = rdev->desc->ops->disable(rdev);
1549		if (ret != 0)
1550			return ret;
1551	}
1552
1553	trace_regulator_disable_complete(rdev_get_name(rdev));
1554
1555	_notifier_call_chain(rdev, REGULATOR_EVENT_DISABLE,
1556			     NULL);
1557	return 0;
1558}
1559
1560/* locks held by regulator_disable() */
1561static int _regulator_disable(struct regulator_dev *rdev)
1562{
1563	int ret = 0;
1564
1565	if (WARN(rdev->use_count <= 0,
1566		 "unbalanced disables for %s\n", rdev_get_name(rdev)))
1567		return -EIO;
1568
1569	/* are we the last user and permitted to disable ? */
1570	if (rdev->use_count == 1 &&
1571	    (rdev->constraints && !rdev->constraints->always_on)) {
1572
1573		/* we are last user */
1574		if (_regulator_can_change_status(rdev)) {
1575			ret = _regulator_do_disable(rdev);
1576			if (ret < 0) {
1577				rdev_err(rdev, "failed to disable\n");
1578				return ret;
1579			}
1580		}
1581
1582		rdev->use_count = 0;
1583	} else if (rdev->use_count > 1) {
1584
1585		if (rdev->constraints &&
1586			(rdev->constraints->valid_ops_mask &
1587			REGULATOR_CHANGE_DRMS))
1588			drms_uA_update(rdev);
1589
1590		rdev->use_count--;
1591	}
1592
1593	return ret;
1594}
1595
1596/**
1597 * regulator_disable - disable regulator output
1598 * @regulator: regulator source
1599 *
1600 * Disable the regulator output voltage or current.  Calls to
1601 * regulator_enable() must be balanced with calls to
1602 * regulator_disable().
1603 *
1604 * NOTE: this will only disable the regulator output if no other consumer
1605 * devices have it enabled, the regulator device supports disabling and
1606 * machine constraints permit this operation.
1607 */
1608int regulator_disable(struct regulator *regulator)
1609{
1610	struct regulator_dev *rdev = regulator->rdev;
1611	int ret = 0;
1612
1613	if (regulator->always_on)
1614		return 0;
1615
1616	mutex_lock(&rdev->mutex);
1617	ret = _regulator_disable(rdev);
1618	mutex_unlock(&rdev->mutex);
1619
1620	if (ret == 0 && rdev->supply)
1621		regulator_disable(rdev->supply);
1622
1623	return ret;
1624}
1625EXPORT_SYMBOL_GPL(regulator_disable);
1626
1627/* locks held by regulator_force_disable() */
1628static int _regulator_force_disable(struct regulator_dev *rdev)
1629{
1630	int ret = 0;
1631
1632	/* force disable */
1633	if (rdev->desc->ops->disable) {
1634		/* ah well, who wants to live forever... */
1635		ret = rdev->desc->ops->disable(rdev);
1636		if (ret < 0) {
1637			rdev_err(rdev, "failed to force disable\n");
1638			return ret;
1639		}
1640		/* notify other consumers that power has been forced off */
1641		_notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
1642			REGULATOR_EVENT_DISABLE, NULL);
1643	}
1644
1645	return ret;
1646}
1647
1648/**
1649 * regulator_force_disable - force disable regulator output
1650 * @regulator: regulator source
1651 *
1652 * Forcibly disable the regulator output voltage or current.
1653 * NOTE: this *will* disable the regulator output even if other consumer
1654 * devices have it enabled. This should be used for situations when device
1655 * damage will likely occur if the regulator is not disabled (e.g. over temp).
1656 */
1657int regulator_force_disable(struct regulator *regulator)
1658{
1659	struct regulator_dev *rdev = regulator->rdev;
1660	int ret;
1661
1662	mutex_lock(&rdev->mutex);
1663	regulator->uA_load = 0;
1664	ret = _regulator_force_disable(regulator->rdev);
1665	mutex_unlock(&rdev->mutex);
1666
1667	if (rdev->supply)
1668		while (rdev->open_count--)
1669			regulator_disable(rdev->supply);
1670
1671	return ret;
1672}
1673EXPORT_SYMBOL_GPL(regulator_force_disable);
1674
1675static void regulator_disable_work(struct work_struct *work)
1676{
1677	struct regulator_dev *rdev = container_of(work, struct regulator_dev,
1678						  disable_work.work);
1679	int count, i, ret;
1680
1681	mutex_lock(&rdev->mutex);
1682
1683	BUG_ON(!rdev->deferred_disables);
1684
1685	count = rdev->deferred_disables;
1686	rdev->deferred_disables = 0;
1687
1688	for (i = 0; i < count; i++) {
1689		ret = _regulator_disable(rdev);
1690		if (ret != 0)
1691			rdev_err(rdev, "Deferred disable failed: %d\n", ret);
1692	}
1693
1694	mutex_unlock(&rdev->mutex);
1695
1696	if (rdev->supply) {
1697		for (i = 0; i < count; i++) {
1698			ret = regulator_disable(rdev->supply);
1699			if (ret != 0) {
1700				rdev_err(rdev,
1701					 "Supply disable failed: %d\n", ret);
1702			}
1703		}
1704	}
1705}
1706
1707/**
1708 * regulator_disable_deferred - disable regulator output with delay
1709 * @regulator: regulator source
1710 * @ms: miliseconds until the regulator is disabled
1711 *
1712 * Execute regulator_disable() on the regulator after a delay.  This
1713 * is intended for use with devices that require some time to quiesce.
1714 *
1715 * NOTE: this will only disable the regulator output if no other consumer
1716 * devices have it enabled, the regulator device supports disabling and
1717 * machine constraints permit this operation.
1718 */
1719int regulator_disable_deferred(struct regulator *regulator, int ms)
1720{
1721	struct regulator_dev *rdev = regulator->rdev;
1722	int ret;
1723
1724	if (regulator->always_on)
1725		return 0;
1726
1727	mutex_lock(&rdev->mutex);
1728	rdev->deferred_disables++;
1729	mutex_unlock(&rdev->mutex);
1730
1731	ret = schedule_delayed_work(&rdev->disable_work,
1732				    msecs_to_jiffies(ms));
1733	if (ret < 0)
1734		return ret;
1735	else
1736		return 0;
1737}
1738EXPORT_SYMBOL_GPL(regulator_disable_deferred);
1739
1740/**
1741 * regulator_is_enabled_regmap - standard is_enabled() for regmap users
1742 *
1743 * @rdev: regulator to operate on
1744 *
1745 * Regulators that use regmap for their register I/O can set the
1746 * enable_reg and enable_mask fields in their descriptor and then use
1747 * this as their is_enabled operation, saving some code.
1748 */
1749int regulator_is_enabled_regmap(struct regulator_dev *rdev)
1750{
1751	unsigned int val;
1752	int ret;
1753
1754	ret = regmap_read(rdev->regmap, rdev->desc->enable_reg, &val);
1755	if (ret != 0)
1756		return ret;
1757
1758	return (val & rdev->desc->enable_mask) != 0;
1759}
1760EXPORT_SYMBOL_GPL(regulator_is_enabled_regmap);
1761
1762/**
1763 * regulator_enable_regmap - standard enable() for regmap users
1764 *
1765 * @rdev: regulator to operate on
1766 *
1767 * Regulators that use regmap for their register I/O can set the
1768 * enable_reg and enable_mask fields in their descriptor and then use
1769 * this as their enable() operation, saving some code.
1770 */
1771int regulator_enable_regmap(struct regulator_dev *rdev)
1772{
1773	return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
1774				  rdev->desc->enable_mask,
1775				  rdev->desc->enable_mask);
1776}
1777EXPORT_SYMBOL_GPL(regulator_enable_regmap);
1778
1779/**
1780 * regulator_disable_regmap - standard disable() for regmap users
1781 *
1782 * @rdev: regulator to operate on
1783 *
1784 * Regulators that use regmap for their register I/O can set the
1785 * enable_reg and enable_mask fields in their descriptor and then use
1786 * this as their disable() operation, saving some code.
1787 */
1788int regulator_disable_regmap(struct regulator_dev *rdev)
1789{
1790	return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
1791				  rdev->desc->enable_mask, 0);
1792}
1793EXPORT_SYMBOL_GPL(regulator_disable_regmap);
1794
1795static int _regulator_is_enabled(struct regulator_dev *rdev)
1796{
1797	/* A GPIO control always takes precedence */
1798	if (rdev->ena_gpio)
1799		return rdev->ena_gpio_state;
1800
1801	/* If we don't know then assume that the regulator is always on */
1802	if (!rdev->desc->ops->is_enabled)
1803		return 1;
1804
1805	return rdev->desc->ops->is_enabled(rdev);
1806}
1807
1808/**
1809 * regulator_is_enabled - is the regulator output enabled
1810 * @regulator: regulator source
1811 *
1812 * Returns positive if the regulator driver backing the source/client
1813 * has requested that the device be enabled, zero if it hasn't, else a
1814 * negative errno code.
1815 *
1816 * Note that the device backing this regulator handle can have multiple
1817 * users, so it might be enabled even if regulator_enable() was never
1818 * called for this particular source.
1819 */
1820int regulator_is_enabled(struct regulator *regulator)
1821{
1822	int ret;
1823
1824	if (regulator->always_on)
1825		return 1;
1826
1827	mutex_lock(&regulator->rdev->mutex);
1828	ret = _regulator_is_enabled(regulator->rdev);
1829	mutex_unlock(&regulator->rdev->mutex);
1830
1831	return ret;
1832}
1833EXPORT_SYMBOL_GPL(regulator_is_enabled);
1834
1835/**
1836 * regulator_count_voltages - count regulator_list_voltage() selectors
1837 * @regulator: regulator source
1838 *
1839 * Returns number of selectors, or negative errno.  Selectors are
1840 * numbered starting at zero, and typically correspond to bitfields
1841 * in hardware registers.
1842 */
1843int regulator_count_voltages(struct regulator *regulator)
1844{
1845	struct regulator_dev	*rdev = regulator->rdev;
1846
1847	return rdev->desc->n_voltages ? : -EINVAL;
1848}
1849EXPORT_SYMBOL_GPL(regulator_count_voltages);
1850
1851/**
1852 * regulator_list_voltage_linear - List voltages with simple calculation
1853 *
1854 * @rdev: Regulator device
1855 * @selector: Selector to convert into a voltage
1856 *
1857 * Regulators with a simple linear mapping between voltages and
1858 * selectors can set min_uV and uV_step in the regulator descriptor
1859 * and then use this function as their list_voltage() operation,
1860 */
1861int regulator_list_voltage_linear(struct regulator_dev *rdev,
1862				  unsigned int selector)
1863{
1864	if (selector >= rdev->desc->n_voltages)
1865		return -EINVAL;
1866
1867	return rdev->desc->min_uV + (rdev->desc->uV_step * selector);
1868}
1869EXPORT_SYMBOL_GPL(regulator_list_voltage_linear);
1870
1871/**
1872 * regulator_list_voltage_table - List voltages with table based mapping
1873 *
1874 * @rdev: Regulator device
1875 * @selector: Selector to convert into a voltage
1876 *
1877 * Regulators with table based mapping between voltages and
1878 * selectors can set volt_table in the regulator descriptor
1879 * and then use this function as their list_voltage() operation.
1880 */
1881int regulator_list_voltage_table(struct regulator_dev *rdev,
1882				 unsigned int selector)
1883{
1884	if (!rdev->desc->volt_table) {
1885		BUG_ON(!rdev->desc->volt_table);
1886		return -EINVAL;
1887	}
1888
1889	if (selector >= rdev->desc->n_voltages)
1890		return -EINVAL;
1891
1892	return rdev->desc->volt_table[selector];
1893}
1894EXPORT_SYMBOL_GPL(regulator_list_voltage_table);
1895
1896/**
1897 * regulator_list_voltage - enumerate supported voltages
1898 * @regulator: regulator source
1899 * @selector: identify voltage to list
1900 * Context: can sleep
1901 *
1902 * Returns a voltage that can be passed to @regulator_set_voltage(),
1903 * zero if this selector code can't be used on this system, or a
1904 * negative errno.
1905 */
1906int regulator_list_voltage(struct regulator *regulator, unsigned selector)
1907{
1908	struct regulator_dev	*rdev = regulator->rdev;
1909	struct regulator_ops	*ops = rdev->desc->ops;
1910	int			ret;
1911
1912	if (!ops->list_voltage || selector >= rdev->desc->n_voltages)
1913		return -EINVAL;
1914
1915	mutex_lock(&rdev->mutex);
1916	ret = ops->list_voltage(rdev, selector);
1917	mutex_unlock(&rdev->mutex);
1918
1919	if (ret > 0) {
1920		if (ret < rdev->constraints->min_uV)
1921			ret = 0;
1922		else if (ret > rdev->constraints->max_uV)
1923			ret = 0;
1924	}
1925
1926	return ret;
1927}
1928EXPORT_SYMBOL_GPL(regulator_list_voltage);
1929
1930/**
1931 * regulator_is_supported_voltage - check if a voltage range can be supported
1932 *
1933 * @regulator: Regulator to check.
1934 * @min_uV: Minimum required voltage in uV.
1935 * @max_uV: Maximum required voltage in uV.
1936 *
1937 * Returns a boolean or a negative error code.
1938 */
1939int regulator_is_supported_voltage(struct regulator *regulator,
1940				   int min_uV, int max_uV)
1941{
1942	struct regulator_dev *rdev = regulator->rdev;
1943	int i, voltages, ret;
1944
1945	/* If we can't change voltage check the current voltage */
1946	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
1947		ret = regulator_get_voltage(regulator);
1948		if (ret >= 0)
1949			return (min_uV >= ret && ret <= max_uV);
1950		else
1951			return ret;
1952	}
1953
1954	ret = regulator_count_voltages(regulator);
1955	if (ret < 0)
1956		return ret;
1957	voltages = ret;
1958
1959	for (i = 0; i < voltages; i++) {
1960		ret = regulator_list_voltage(regulator, i);
1961
1962		if (ret >= min_uV && ret <= max_uV)
1963			return 1;
1964	}
1965
1966	return 0;
1967}
1968EXPORT_SYMBOL_GPL(regulator_is_supported_voltage);
1969
1970/**
1971 * regulator_get_voltage_sel_regmap - standard get_voltage_sel for regmap users
1972 *
1973 * @rdev: regulator to operate on
1974 *
1975 * Regulators that use regmap for their register I/O can set the
1976 * vsel_reg and vsel_mask fields in their descriptor and then use this
1977 * as their get_voltage_vsel operation, saving some code.
1978 */
1979int regulator_get_voltage_sel_regmap(struct regulator_dev *rdev)
1980{
1981	unsigned int val;
1982	int ret;
1983
1984	ret = regmap_read(rdev->regmap, rdev->desc->vsel_reg, &val);
1985	if (ret != 0)
1986		return ret;
1987
1988	val &= rdev->desc->vsel_mask;
1989	val >>= ffs(rdev->desc->vsel_mask) - 1;
1990
1991	return val;
1992}
1993EXPORT_SYMBOL_GPL(regulator_get_voltage_sel_regmap);
1994
1995/**
1996 * regulator_set_voltage_sel_regmap - standard set_voltage_sel for regmap users
1997 *
1998 * @rdev: regulator to operate on
1999 * @sel: Selector to set
2000 *
2001 * Regulators that use regmap for their register I/O can set the
2002 * vsel_reg and vsel_mask fields in their descriptor and then use this
2003 * as their set_voltage_vsel operation, saving some code.
2004 */
2005int regulator_set_voltage_sel_regmap(struct regulator_dev *rdev, unsigned sel)
2006{
2007	sel <<= ffs(rdev->desc->vsel_mask) - 1;
2008
2009	return regmap_update_bits(rdev->regmap, rdev->desc->vsel_reg,
2010				  rdev->desc->vsel_mask, sel);
2011}
2012EXPORT_SYMBOL_GPL(regulator_set_voltage_sel_regmap);
2013
2014/**
2015 * regulator_map_voltage_iterate - map_voltage() based on list_voltage()
2016 *
2017 * @rdev: Regulator to operate on
2018 * @min_uV: Lower bound for voltage
2019 * @max_uV: Upper bound for voltage
2020 *
2021 * Drivers implementing set_voltage_sel() and list_voltage() can use
2022 * this as their map_voltage() operation.  It will find a suitable
2023 * voltage by calling list_voltage() until it gets something in bounds
2024 * for the requested voltages.
2025 */
2026int regulator_map_voltage_iterate(struct regulator_dev *rdev,
2027				  int min_uV, int max_uV)
2028{
2029	int best_val = INT_MAX;
2030	int selector = 0;
2031	int i, ret;
2032
2033	/* Find the smallest voltage that falls within the specified
2034	 * range.
2035	 */
2036	for (i = 0; i < rdev->desc->n_voltages; i++) {
2037		ret = rdev->desc->ops->list_voltage(rdev, i);
2038		if (ret < 0)
2039			continue;
2040
2041		if (ret < best_val && ret >= min_uV && ret <= max_uV) {
2042			best_val = ret;
2043			selector = i;
2044		}
2045	}
2046
2047	if (best_val != INT_MAX)
2048		return selector;
2049	else
2050		return -EINVAL;
2051}
2052EXPORT_SYMBOL_GPL(regulator_map_voltage_iterate);
2053
2054/**
2055 * regulator_map_voltage_linear - map_voltage() for simple linear mappings
2056 *
2057 * @rdev: Regulator to operate on
2058 * @min_uV: Lower bound for voltage
2059 * @max_uV: Upper bound for voltage
2060 *
2061 * Drivers providing min_uV and uV_step in their regulator_desc can
2062 * use this as their map_voltage() operation.
2063 */
2064int regulator_map_voltage_linear(struct regulator_dev *rdev,
2065				 int min_uV, int max_uV)
2066{
2067	int ret, voltage;
2068
2069	/* Allow uV_step to be 0 for fixed voltage */
2070	if (rdev->desc->n_voltages == 1 && rdev->desc->uV_step == 0) {
2071		if (min_uV <= rdev->desc->min_uV && rdev->desc->min_uV <= max_uV)
2072			return 0;
2073		else
2074			return -EINVAL;
2075	}
2076
2077	if (!rdev->desc->uV_step) {
2078		BUG_ON(!rdev->desc->uV_step);
2079		return -EINVAL;
2080	}
2081
2082	if (min_uV < rdev->desc->min_uV)
2083		min_uV = rdev->desc->min_uV;
2084
2085	ret = DIV_ROUND_UP(min_uV - rdev->desc->min_uV, rdev->desc->uV_step);
2086	if (ret < 0)
2087		return ret;
2088
2089	/* Map back into a voltage to verify we're still in bounds */
2090	voltage = rdev->desc->ops->list_voltage(rdev, ret);
2091	if (voltage < min_uV || voltage > max_uV)
2092		return -EINVAL;
2093
2094	return ret;
2095}
2096EXPORT_SYMBOL_GPL(regulator_map_voltage_linear);
2097
2098static int _regulator_do_set_voltage(struct regulator_dev *rdev,
2099				     int min_uV, int max_uV)
2100{
2101	int ret;
2102	int delay = 0;
2103	int best_val = 0;
2104	unsigned int selector;
2105	int old_selector = -1;
2106
2107	trace_regulator_set_voltage(rdev_get_name(rdev), min_uV, max_uV);
2108
2109	min_uV += rdev->constraints->uV_offset;
2110	max_uV += rdev->constraints->uV_offset;
2111
2112	/*
2113	 * If we can't obtain the old selector there is not enough
2114	 * info to call set_voltage_time_sel().
2115	 */
2116	if (_regulator_is_enabled(rdev) &&
2117	    rdev->desc->ops->set_voltage_time_sel &&
2118	    rdev->desc->ops->get_voltage_sel) {
2119		old_selector = rdev->desc->ops->get_voltage_sel(rdev);
2120		if (old_selector < 0)
2121			return old_selector;
2122	}
2123
2124	if (rdev->desc->ops->set_voltage) {
2125		ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV,
2126						   &selector);
2127
2128		if (ret >= 0) {
2129			if (rdev->desc->ops->list_voltage)
2130				best_val = rdev->desc->ops->list_voltage(rdev,
2131									 selector);
2132			else
2133				best_val = _regulator_get_voltage(rdev);
2134		}
2135
2136	} else if (rdev->desc->ops->set_voltage_sel) {
2137		if (rdev->desc->ops->map_voltage) {
2138			ret = rdev->desc->ops->map_voltage(rdev, min_uV,
2139							   max_uV);
2140		} else {
2141			if (rdev->desc->ops->list_voltage ==
2142			    regulator_list_voltage_linear)
2143				ret = regulator_map_voltage_linear(rdev,
2144								min_uV, max_uV);
2145			else
2146				ret = regulator_map_voltage_iterate(rdev,
2147								min_uV, max_uV);
2148		}
2149
2150		if (ret >= 0) {
2151			best_val = rdev->desc->ops->list_voltage(rdev, ret);
2152			if (min_uV <= best_val && max_uV >= best_val) {
2153				selector = ret;
2154				ret = rdev->desc->ops->set_voltage_sel(rdev,
2155								       ret);
2156			} else {
2157				ret = -EINVAL;
2158			}
2159		}
2160	} else {
2161		ret = -EINVAL;
2162	}
2163
2164	/* Call set_voltage_time_sel if successfully obtained old_selector */
2165	if (ret == 0 && _regulator_is_enabled(rdev) && old_selector >= 0 &&
2166	    rdev->desc->ops->set_voltage_time_sel) {
2167
2168		delay = rdev->desc->ops->set_voltage_time_sel(rdev,
2169						old_selector, selector);
2170		if (delay < 0) {
2171			rdev_warn(rdev, "set_voltage_time_sel() failed: %d\n",
2172				  delay);
2173			delay = 0;
2174		}
2175
2176		/* Insert any necessary delays */
2177		if (delay >= 1000) {
2178			mdelay(delay / 1000);
2179			udelay(delay % 1000);
2180		} else if (delay) {
2181			udelay(delay);
2182		}
2183	}
2184
2185	if (ret == 0 && best_val >= 0) {
2186		unsigned long data = best_val;
2187
2188		_notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE,
2189				     (void *)data);
2190	}
2191
2192	trace_regulator_set_voltage_complete(rdev_get_name(rdev), best_val);
2193
2194	return ret;
2195}
2196
2197/**
2198 * regulator_set_voltage - set regulator output voltage
2199 * @regulator: regulator source
2200 * @min_uV: Minimum required voltage in uV
2201 * @max_uV: Maximum acceptable voltage in uV
2202 *
2203 * Sets a voltage regulator to the desired output voltage. This can be set
2204 * during any regulator state. IOW, regulator can be disabled or enabled.
2205 *
2206 * If the regulator is enabled then the voltage will change to the new value
2207 * immediately otherwise if the regulator is disabled the regulator will
2208 * output at the new voltage when enabled.
2209 *
2210 * NOTE: If the regulator is shared between several devices then the lowest
2211 * request voltage that meets the system constraints will be used.
2212 * Regulator system constraints must be set for this regulator before
2213 * calling this function otherwise this call will fail.
2214 */
2215int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
2216{
2217	struct regulator_dev *rdev = regulator->rdev;
2218	int ret = 0;
2219
2220	mutex_lock(&rdev->mutex);
2221
2222	/* If we're setting the same range as last time the change
2223	 * should be a noop (some cpufreq implementations use the same
2224	 * voltage for multiple frequencies, for example).
2225	 */
2226	if (regulator->min_uV == min_uV && regulator->max_uV == max_uV)
2227		goto out;
2228
2229	/* sanity check */
2230	if (!rdev->desc->ops->set_voltage &&
2231	    !rdev->desc->ops->set_voltage_sel) {
2232		ret = -EINVAL;
2233		goto out;
2234	}
2235
2236	/* constraints check */
2237	ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
2238	if (ret < 0)
2239		goto out;
2240	regulator->min_uV = min_uV;
2241	regulator->max_uV = max_uV;
2242
2243	ret = regulator_check_consumers(rdev, &min_uV, &max_uV);
2244	if (ret < 0)
2245		goto out;
2246
2247	ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
2248
2249out:
2250	mutex_unlock(&rdev->mutex);
2251	return ret;
2252}
2253EXPORT_SYMBOL_GPL(regulator_set_voltage);
2254
2255/**
2256 * regulator_set_voltage_time - get raise/fall time
2257 * @regulator: regulator source
2258 * @old_uV: starting voltage in microvolts
2259 * @new_uV: target voltage in microvolts
2260 *
2261 * Provided with the starting and ending voltage, this function attempts to
2262 * calculate the time in microseconds required to rise or fall to this new
2263 * voltage.
2264 */
2265int regulator_set_voltage_time(struct regulator *regulator,
2266			       int old_uV, int new_uV)
2267{
2268	struct regulator_dev	*rdev = regulator->rdev;
2269	struct regulator_ops	*ops = rdev->desc->ops;
2270	int old_sel = -1;
2271	int new_sel = -1;
2272	int voltage;
2273	int i;
2274
2275	/* Currently requires operations to do this */
2276	if (!ops->list_voltage || !ops->set_voltage_time_sel
2277	    || !rdev->desc->n_voltages)
2278		return -EINVAL;
2279
2280	for (i = 0; i < rdev->desc->n_voltages; i++) {
2281		/* We only look for exact voltage matches here */
2282		voltage = regulator_list_voltage(regulator, i);
2283		if (voltage < 0)
2284			return -EINVAL;
2285		if (voltage == 0)
2286			continue;
2287		if (voltage == old_uV)
2288			old_sel = i;
2289		if (voltage == new_uV)
2290			new_sel = i;
2291	}
2292
2293	if (old_sel < 0 || new_sel < 0)
2294		return -EINVAL;
2295
2296	return ops->set_voltage_time_sel(rdev, old_sel, new_sel);
2297}
2298EXPORT_SYMBOL_GPL(regulator_set_voltage_time);
2299
2300/**
2301 *regulator_set_voltage_time_sel - get raise/fall time
2302 * @regulator: regulator source
2303 * @old_selector: selector for starting voltage
2304 * @new_selector: selector for target voltage
2305 *
2306 * Provided with the starting and target voltage selectors, this function
2307 * returns time in microseconds required to rise or fall to this new voltage
2308 *
2309 * Drivers providing ramp_delay in regulation_constraints can use this as their
2310 * set_voltage_time_sel() operation.
2311 */
2312int regulator_set_voltage_time_sel(struct regulator_dev *rdev,
2313				   unsigned int old_selector,
2314				   unsigned int new_selector)
2315{
2316	unsigned int ramp_delay = 0;
2317	int old_volt, new_volt;
2318
2319	if (rdev->constraints->ramp_delay)
2320		ramp_delay = rdev->constraints->ramp_delay;
2321	else if (rdev->desc->ramp_delay)
2322		ramp_delay = rdev->desc->ramp_delay;
2323
2324	if (ramp_delay == 0) {
2325		rdev_warn(rdev, "ramp_delay not set\n");
2326		return 0;
2327	}
2328
2329	/* sanity check */
2330	if (!rdev->desc->ops->list_voltage)
2331		return -EINVAL;
2332
2333	old_volt = rdev->desc->ops->list_voltage(rdev, old_selector);
2334	new_volt = rdev->desc->ops->list_voltage(rdev, new_selector);
2335
2336	return DIV_ROUND_UP(abs(new_volt - old_volt), ramp_delay);
2337}
2338EXPORT_SYMBOL_GPL(regulator_set_voltage_time_sel);
2339
2340/**
2341 * regulator_sync_voltage - re-apply last regulator output voltage
2342 * @regulator: regulator source
2343 *
2344 * Re-apply the last configured voltage.  This is intended to be used
2345 * where some external control source the consumer is cooperating with
2346 * has caused the configured voltage to change.
2347 */
2348int regulator_sync_voltage(struct regulator *regulator)
2349{
2350	struct regulator_dev *rdev = regulator->rdev;
2351	int ret, min_uV, max_uV;
2352
2353	mutex_lock(&rdev->mutex);
2354
2355	if (!rdev->desc->ops->set_voltage &&
2356	    !rdev->desc->ops->set_voltage_sel) {
2357		ret = -EINVAL;
2358		goto out;
2359	}
2360
2361	/* This is only going to work if we've had a voltage configured. */
2362	if (!regulator->min_uV && !regulator->max_uV) {
2363		ret = -EINVAL;
2364		goto out;
2365	}
2366
2367	min_uV = regulator->min_uV;
2368	max_uV = regulator->max_uV;
2369
2370	/* This should be a paranoia check... */
2371	ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
2372	if (ret < 0)
2373		goto out;
2374
2375	ret = regulator_check_consumers(rdev, &min_uV, &max_uV);
2376	if (ret < 0)
2377		goto out;
2378
2379	ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
2380
2381out:
2382	mutex_unlock(&rdev->mutex);
2383	return ret;
2384}
2385EXPORT_SYMBOL_GPL(regulator_sync_voltage);
2386
2387static int _regulator_get_voltage(struct regulator_dev *rdev)
2388{
2389	int sel, ret;
2390
2391	if (rdev->desc->ops->get_voltage_sel) {
2392		sel = rdev->desc->ops->get_voltage_sel(rdev);
2393		if (sel < 0)
2394			return sel;
2395		ret = rdev->desc->ops->list_voltage(rdev, sel);
2396	} else if (rdev->desc->ops->get_voltage) {
2397		ret = rdev->desc->ops->get_voltage(rdev);
2398	} else {
2399		return -EINVAL;
2400	}
2401
2402	if (ret < 0)
2403		return ret;
2404	return ret - rdev->constraints->uV_offset;
2405}
2406
2407/**
2408 * regulator_get_voltage - get regulator output voltage
2409 * @regulator: regulator source
2410 *
2411 * This returns the current regulator voltage in uV.
2412 *
2413 * NOTE: If the regulator is disabled it will return the voltage value. This
2414 * function should not be used to determine regulator state.
2415 */
2416int regulator_get_voltage(struct regulator *regulator)
2417{
2418	int ret;
2419
2420	mutex_lock(&regulator->rdev->mutex);
2421
2422	ret = _regulator_get_voltage(regulator->rdev);
2423
2424	mutex_unlock(&regulator->rdev->mutex);
2425
2426	return ret;
2427}
2428EXPORT_SYMBOL_GPL(regulator_get_voltage);
2429
2430/**
2431 * regulator_set_current_limit - set regulator output current limit
2432 * @regulator: regulator source
2433 * @min_uA: Minimuum supported current in uA
2434 * @max_uA: Maximum supported current in uA
2435 *
2436 * Sets current sink to the desired output current. This can be set during
2437 * any regulator state. IOW, regulator can be disabled or enabled.
2438 *
2439 * If the regulator is enabled then the current will change to the new value
2440 * immediately otherwise if the regulator is disabled the regulator will
2441 * output at the new current when enabled.
2442 *
2443 * NOTE: Regulator system constraints must be set for this regulator before
2444 * calling this function otherwise this call will fail.
2445 */
2446int regulator_set_current_limit(struct regulator *regulator,
2447			       int min_uA, int max_uA)
2448{
2449	struct regulator_dev *rdev = regulator->rdev;
2450	int ret;
2451
2452	mutex_lock(&rdev->mutex);
2453
2454	/* sanity check */
2455	if (!rdev->desc->ops->set_current_limit) {
2456		ret = -EINVAL;
2457		goto out;
2458	}
2459
2460	/* constraints check */
2461	ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
2462	if (ret < 0)
2463		goto out;
2464
2465	ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
2466out:
2467	mutex_unlock(&rdev->mutex);
2468	return ret;
2469}
2470EXPORT_SYMBOL_GPL(regulator_set_current_limit);
2471
2472static int _regulator_get_current_limit(struct regulator_dev *rdev)
2473{
2474	int ret;
2475
2476	mutex_lock(&rdev->mutex);
2477
2478	/* sanity check */
2479	if (!rdev->desc->ops->get_current_limit) {
2480		ret = -EINVAL;
2481		goto out;
2482	}
2483
2484	ret = rdev->desc->ops->get_current_limit(rdev);
2485out:
2486	mutex_unlock(&rdev->mutex);
2487	return ret;
2488}
2489
2490/**
2491 * regulator_get_current_limit - get regulator output current
2492 * @regulator: regulator source
2493 *
2494 * This returns the current supplied by the specified current sink in uA.
2495 *
2496 * NOTE: If the regulator is disabled it will return the current value. This
2497 * function should not be used to determine regulator state.
2498 */
2499int regulator_get_current_limit(struct regulator *regulator)
2500{
2501	return _regulator_get_current_limit(regulator->rdev);
2502}
2503EXPORT_SYMBOL_GPL(regulator_get_current_limit);
2504
2505/**
2506 * regulator_set_mode - set regulator operating mode
2507 * @regulator: regulator source
2508 * @mode: operating mode - one of the REGULATOR_MODE constants
2509 *
2510 * Set regulator operating mode to increase regulator efficiency or improve
2511 * regulation performance.
2512 *
2513 * NOTE: Regulator system constraints must be set for this regulator before
2514 * calling this function otherwise this call will fail.
2515 */
2516int regulator_set_mode(struct regulator *regulator, unsigned int mode)
2517{
2518	struct regulator_dev *rdev = regulator->rdev;
2519	int ret;
2520	int regulator_curr_mode;
2521
2522	mutex_lock(&rdev->mutex);
2523
2524	/* sanity check */
2525	if (!rdev->desc->ops->set_mode) {
2526		ret = -EINVAL;
2527		goto out;
2528	}
2529
2530	/* return if the same mode is requested */
2531	if (rdev->desc->ops->get_mode) {
2532		regulator_curr_mode = rdev->desc->ops->get_mode(rdev);
2533		if (regulator_curr_mode == mode) {
2534			ret = 0;
2535			goto out;
2536		}
2537	}
2538
2539	/* constraints check */
2540	ret = regulator_mode_constrain(rdev, &mode);
2541	if (ret < 0)
2542		goto out;
2543
2544	ret = rdev->desc->ops->set_mode(rdev, mode);
2545out:
2546	mutex_unlock(&rdev->mutex);
2547	return ret;
2548}
2549EXPORT_SYMBOL_GPL(regulator_set_mode);
2550
2551static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
2552{
2553	int ret;
2554
2555	mutex_lock(&rdev->mutex);
2556
2557	/* sanity check */
2558	if (!rdev->desc->ops->get_mode) {
2559		ret = -EINVAL;
2560		goto out;
2561	}
2562
2563	ret = rdev->desc->ops->get_mode(rdev);
2564out:
2565	mutex_unlock(&rdev->mutex);
2566	return ret;
2567}
2568
2569/**
2570 * regulator_get_mode - get regulator operating mode
2571 * @regulator: regulator source
2572 *
2573 * Get the current regulator operating mode.
2574 */
2575unsigned int regulator_get_mode(struct regulator *regulator)
2576{
2577	return _regulator_get_mode(regulator->rdev);
2578}
2579EXPORT_SYMBOL_GPL(regulator_get_mode);
2580
2581/**
2582 * regulator_set_optimum_mode - set regulator optimum operating mode
2583 * @regulator: regulator source
2584 * @uA_load: load current
2585 *
2586 * Notifies the regulator core of a new device load. This is then used by
2587 * DRMS (if enabled by constraints) to set the most efficient regulator
2588 * operating mode for the new regulator loading.
2589 *
2590 * Consumer devices notify their supply regulator of the maximum power
2591 * they will require (can be taken from device datasheet in the power
2592 * consumption tables) when they change operational status and hence power
2593 * state. Examples of operational state changes that can affect power
2594 * consumption are :-
2595 *
2596 *    o Device is opened / closed.
2597 *    o Device I/O is about to begin or has just finished.
2598 *    o Device is idling in between work.
2599 *
2600 * This information is also exported via sysfs to userspace.
2601 *
2602 * DRMS will sum the total requested load on the regulator and change
2603 * to the most efficient operating mode if platform constraints allow.
2604 *
2605 * Returns the new regulator mode or error.
2606 */
2607int regulator_set_optimum_mode(struct regulator *regulator, int uA_load)
2608{
2609	struct regulator_dev *rdev = regulator->rdev;
2610	struct regulator *consumer;
2611	int ret, output_uV, input_uV = 0, total_uA_load = 0;
2612	unsigned int mode;
2613
2614	if (rdev->supply)
2615		input_uV = regulator_get_voltage(rdev->supply);
2616
2617	mutex_lock(&rdev->mutex);
2618
2619	/*
2620	 * first check to see if we can set modes at all, otherwise just
2621	 * tell the consumer everything is OK.
2622	 */
2623	regulator->uA_load = uA_load;
2624	ret = regulator_check_drms(rdev);
2625	if (ret < 0) {
2626		ret = 0;
2627		goto out;
2628	}
2629
2630	if (!rdev->desc->ops->get_optimum_mode)
2631		goto out;
2632
2633	/*
2634	 * we can actually do this so any errors are indicators of
2635	 * potential real failure.
2636	 */
2637	ret = -EINVAL;
2638
2639	if (!rdev->desc->ops->set_mode)
2640		goto out;
2641
2642	/* get output voltage */
2643	output_uV = _regulator_get_voltage(rdev);
2644	if (output_uV <= 0) {
2645		rdev_err(rdev, "invalid output voltage found\n");
2646		goto out;
2647	}
2648
2649	/* No supply? Use constraint voltage */
2650	if (input_uV <= 0)
2651		input_uV = rdev->constraints->input_uV;
2652	if (input_uV <= 0) {
2653		rdev_err(rdev, "invalid input voltage found\n");
2654		goto out;
2655	}
2656
2657	/* calc total requested load for this regulator */
2658	list_for_each_entry(consumer, &rdev->consumer_list, list)
2659		total_uA_load += consumer->uA_load;
2660
2661	mode = rdev->desc->ops->get_optimum_mode(rdev,
2662						 input_uV, output_uV,
2663						 total_uA_load);
2664	ret = regulator_mode_constrain(rdev, &mode);
2665	if (ret < 0) {
2666		rdev_err(rdev, "failed to get optimum mode @ %d uA %d -> %d uV\n",
2667			 total_uA_load, input_uV, output_uV);
2668		goto out;
2669	}
2670
2671	ret = rdev->desc->ops->set_mode(rdev, mode);
2672	if (ret < 0) {
2673		rdev_err(rdev, "failed to set optimum mode %x\n", mode);
2674		goto out;
2675	}
2676	ret = mode;
2677out:
2678	mutex_unlock(&rdev->mutex);
2679	return ret;
2680}
2681EXPORT_SYMBOL_GPL(regulator_set_optimum_mode);
2682
2683/**
2684 * regulator_register_notifier - register regulator event notifier
2685 * @regulator: regulator source
2686 * @nb: notifier block
2687 *
2688 * Register notifier block to receive regulator events.
2689 */
2690int regulator_register_notifier(struct regulator *regulator,
2691			      struct notifier_block *nb)
2692{
2693	return blocking_notifier_chain_register(&regulator->rdev->notifier,
2694						nb);
2695}
2696EXPORT_SYMBOL_GPL(regulator_register_notifier);
2697
2698/**
2699 * regulator_unregister_notifier - unregister regulator event notifier
2700 * @regulator: regulator source
2701 * @nb: notifier block
2702 *
2703 * Unregister regulator event notifier block.
2704 */
2705int regulator_unregister_notifier(struct regulator *regulator,
2706				struct notifier_block *nb)
2707{
2708	return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
2709						  nb);
2710}
2711EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
2712
2713/* notify regulator consumers and downstream regulator consumers.
2714 * Note mutex must be held by caller.
2715 */
2716static void _notifier_call_chain(struct regulator_dev *rdev,
2717				  unsigned long event, void *data)
2718{
2719	/* call rdev chain first */
2720	blocking_notifier_call_chain(&rdev->notifier, event, data);
2721}
2722
2723/**
2724 * regulator_bulk_get - get multiple regulator consumers
2725 *
2726 * @dev:           Device to supply
2727 * @num_consumers: Number of consumers to register
2728 * @consumers:     Configuration of consumers; clients are stored here.
2729 *
2730 * @return 0 on success, an errno on failure.
2731 *
2732 * This helper function allows drivers to get several regulator
2733 * consumers in one operation.  If any of the regulators cannot be
2734 * acquired then any regulators that were allocated will be freed
2735 * before returning to the caller.
2736 */
2737int regulator_bulk_get(struct device *dev, int num_consumers,
2738		       struct regulator_bulk_data *consumers)
2739{
2740	int i;
2741	int ret;
2742
2743	for (i = 0; i < num_consumers; i++)
2744		consumers[i].consumer = NULL;
2745
2746	for (i = 0; i < num_consumers; i++) {
2747		consumers[i].consumer = regulator_get(dev,
2748						      consumers[i].supply);
2749		if (IS_ERR(consumers[i].consumer)) {
2750			ret = PTR_ERR(consumers[i].consumer);
2751			dev_err(dev, "Failed to get supply '%s': %d\n",
2752				consumers[i].supply, ret);
2753			consumers[i].consumer = NULL;
2754			goto err;
2755		}
2756	}
2757
2758	return 0;
2759
2760err:
2761	while (--i >= 0)
2762		regulator_put(consumers[i].consumer);
2763
2764	return ret;
2765}
2766EXPORT_SYMBOL_GPL(regulator_bulk_get);
2767
2768/**
2769 * devm_regulator_bulk_get - managed get multiple regulator consumers
2770 *
2771 * @dev:           Device to supply
2772 * @num_consumers: Number of consumers to register
2773 * @consumers:     Configuration of consumers; clients are stored here.
2774 *
2775 * @return 0 on success, an errno on failure.
2776 *
2777 * This helper function allows drivers to get several regulator
2778 * consumers in one operation with management, the regulators will
2779 * automatically be freed when the device is unbound.  If any of the
2780 * regulators cannot be acquired then any regulators that were
2781 * allocated will be freed before returning to the caller.
2782 */
2783int devm_regulator_bulk_get(struct device *dev, int num_consumers,
2784			    struct regulator_bulk_data *consumers)
2785{
2786	int i;
2787	int ret;
2788
2789	for (i = 0; i < num_consumers; i++)
2790		consumers[i].consumer = NULL;
2791
2792	for (i = 0; i < num_consumers; i++) {
2793		consumers[i].consumer = devm_regulator_get(dev,
2794							   consumers[i].supply);
2795		if (IS_ERR(consumers[i].consumer)) {
2796			ret = PTR_ERR(consumers[i].consumer);
2797			dev_err(dev, "Failed to get supply '%s': %d\n",
2798				consumers[i].supply, ret);
2799			consumers[i].consumer = NULL;
2800			goto err;
2801		}
2802	}
2803
2804	return 0;
2805
2806err:
2807	for (i = 0; i < num_consumers && consumers[i].consumer; i++)
2808		devm_regulator_put(consumers[i].consumer);
2809
2810	return ret;
2811}
2812EXPORT_SYMBOL_GPL(devm_regulator_bulk_get);
2813
2814static void regulator_bulk_enable_async(void *data, async_cookie_t cookie)
2815{
2816	struct regulator_bulk_data *bulk = data;
2817
2818	bulk->ret = regulator_enable(bulk->consumer);
2819}
2820
2821/**
2822 * regulator_bulk_enable - enable multiple regulator consumers
2823 *
2824 * @num_consumers: Number of consumers
2825 * @consumers:     Consumer data; clients are stored here.
2826 * @return         0 on success, an errno on failure
2827 *
2828 * This convenience API allows consumers to enable multiple regulator
2829 * clients in a single API call.  If any consumers cannot be enabled
2830 * then any others that were enabled will be disabled again prior to
2831 * return.
2832 */
2833int regulator_bulk_enable(int num_consumers,
2834			  struct regulator_bulk_data *consumers)
2835{
2836	ASYNC_DOMAIN_EXCLUSIVE(async_domain);
2837	int i;
2838	int ret = 0;
2839
2840	for (i = 0; i < num_consumers; i++) {
2841		if (consumers[i].consumer->always_on)
2842			consumers[i].ret = 0;
2843		else
2844			async_schedule_domain(regulator_bulk_enable_async,
2845					      &consumers[i], &async_domain);
2846	}
2847
2848	async_synchronize_full_domain(&async_domain);
2849
2850	/* If any consumer failed we need to unwind any that succeeded */
2851	for (i = 0; i < num_consumers; i++) {
2852		if (consumers[i].ret != 0) {
2853			ret = consumers[i].ret;
2854			goto err;
2855		}
2856	}
2857
2858	return 0;
2859
2860err:
2861	pr_err("Failed to enable %s: %d\n", consumers[i].supply, ret);
2862	while (--i >= 0)
2863		regulator_disable(consumers[i].consumer);
2864
2865	return ret;
2866}
2867EXPORT_SYMBOL_GPL(regulator_bulk_enable);
2868
2869/**
2870 * regulator_bulk_disable - disable multiple regulator consumers
2871 *
2872 * @num_consumers: Number of consumers
2873 * @consumers:     Consumer data; clients are stored here.
2874 * @return         0 on success, an errno on failure
2875 *
2876 * This convenience API allows consumers to disable multiple regulator
2877 * clients in a single API call.  If any consumers cannot be disabled
2878 * then any others that were disabled will be enabled again prior to
2879 * return.
2880 */
2881int regulator_bulk_disable(int num_consumers,
2882			   struct regulator_bulk_data *consumers)
2883{
2884	int i;
2885	int ret, r;
2886
2887	for (i = num_consumers - 1; i >= 0; --i) {
2888		ret = regulator_disable(consumers[i].consumer);
2889		if (ret != 0)
2890			goto err;
2891	}
2892
2893	return 0;
2894
2895err:
2896	pr_err("Failed to disable %s: %d\n", consumers[i].supply, ret);
2897	for (++i; i < num_consumers; ++i) {
2898		r = regulator_enable(consumers[i].consumer);
2899		if (r != 0)
2900			pr_err("Failed to reename %s: %d\n",
2901			       consumers[i].supply, r);
2902	}
2903
2904	return ret;
2905}
2906EXPORT_SYMBOL_GPL(regulator_bulk_disable);
2907
2908/**
2909 * regulator_bulk_force_disable - force disable multiple regulator consumers
2910 *
2911 * @num_consumers: Number of consumers
2912 * @consumers:     Consumer data; clients are stored here.
2913 * @return         0 on success, an errno on failure
2914 *
2915 * This convenience API allows consumers to forcibly disable multiple regulator
2916 * clients in a single API call.
2917 * NOTE: This should be used for situations when device damage will
2918 * likely occur if the regulators are not disabled (e.g. over temp).
2919 * Although regulator_force_disable function call for some consumers can
2920 * return error numbers, the function is called for all consumers.
2921 */
2922int regulator_bulk_force_disable(int num_consumers,
2923			   struct regulator_bulk_data *consumers)
2924{
2925	int i;
2926	int ret;
2927
2928	for (i = 0; i < num_consumers; i++)
2929		consumers[i].ret =
2930			    regulator_force_disable(consumers[i].consumer);
2931
2932	for (i = 0; i < num_consumers; i++) {
2933		if (consumers[i].ret != 0) {
2934			ret = consumers[i].ret;
2935			goto out;
2936		}
2937	}
2938
2939	return 0;
2940out:
2941	return ret;
2942}
2943EXPORT_SYMBOL_GPL(regulator_bulk_force_disable);
2944
2945/**
2946 * regulator_bulk_free - free multiple regulator consumers
2947 *
2948 * @num_consumers: Number of consumers
2949 * @consumers:     Consumer data; clients are stored here.
2950 *
2951 * This convenience API allows consumers to free multiple regulator
2952 * clients in a single API call.
2953 */
2954void regulator_bulk_free(int num_consumers,
2955			 struct regulator_bulk_data *consumers)
2956{
2957	int i;
2958
2959	for (i = 0; i < num_consumers; i++) {
2960		regulator_put(consumers[i].consumer);
2961		consumers[i].consumer = NULL;
2962	}
2963}
2964EXPORT_SYMBOL_GPL(regulator_bulk_free);
2965
2966/**
2967 * regulator_notifier_call_chain - call regulator event notifier
2968 * @rdev: regulator source
2969 * @event: notifier block
2970 * @data: callback-specific data.
2971 *
2972 * Called by regulator drivers to notify clients a regulator event has
2973 * occurred. We also notify regulator clients downstream.
2974 * Note lock must be held by caller.
2975 */
2976int regulator_notifier_call_chain(struct regulator_dev *rdev,
2977				  unsigned long event, void *data)
2978{
2979	_notifier_call_chain(rdev, event, data);
2980	return NOTIFY_DONE;
2981
2982}
2983EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
2984
2985/**
2986 * regulator_mode_to_status - convert a regulator mode into a status
2987 *
2988 * @mode: Mode to convert
2989 *
2990 * Convert a regulator mode into a status.
2991 */
2992int regulator_mode_to_status(unsigned int mode)
2993{
2994	switch (mode) {
2995	case REGULATOR_MODE_FAST:
2996		return REGULATOR_STATUS_FAST;
2997	case REGULATOR_MODE_NORMAL:
2998		return REGULATOR_STATUS_NORMAL;
2999	case REGULATOR_MODE_IDLE:
3000		return REGULATOR_STATUS_IDLE;
3001	case REGULATOR_MODE_STANDBY:
3002		return REGULATOR_STATUS_STANDBY;
3003	default:
3004		return REGULATOR_STATUS_UNDEFINED;
3005	}
3006}
3007EXPORT_SYMBOL_GPL(regulator_mode_to_status);
3008
3009/*
3010 * To avoid cluttering sysfs (and memory) with useless state, only
3011 * create attributes that can be meaningfully displayed.
3012 */
3013static int add_regulator_attributes(struct regulator_dev *rdev)
3014{
3015	struct device		*dev = &rdev->dev;
3016	struct regulator_ops	*ops = rdev->desc->ops;
3017	int			status = 0;
3018
3019	/* some attributes need specific methods to be displayed */
3020	if ((ops->get_voltage && ops->get_voltage(rdev) >= 0) ||
3021	    (ops->get_voltage_sel && ops->get_voltage_sel(rdev) >= 0)) {
3022		status = device_create_file(dev, &dev_attr_microvolts);
3023		if (status < 0)
3024			return status;
3025	}
3026	if (ops->get_current_limit) {
3027		status = device_create_file(dev, &dev_attr_microamps);
3028		if (status < 0)
3029			return status;
3030	}
3031	if (ops->get_mode) {
3032		status = device_create_file(dev, &dev_attr_opmode);
3033		if (status < 0)
3034			return status;
3035	}
3036	if (ops->is_enabled) {
3037		status = device_create_file(dev, &dev_attr_state);
3038		if (status < 0)
3039			return status;
3040	}
3041	if (ops->get_status) {
3042		status = device_create_file(dev, &dev_attr_status);
3043		if (status < 0)
3044			return status;
3045	}
3046
3047	/* some attributes are type-specific */
3048	if (rdev->desc->type == REGULATOR_CURRENT) {
3049		status = device_create_file(dev, &dev_attr_requested_microamps);
3050		if (status < 0)
3051			return status;
3052	}
3053
3054	/* all the other attributes exist to support constraints;
3055	 * don't show them if there are no constraints, or if the
3056	 * relevant supporting methods are missing.
3057	 */
3058	if (!rdev->constraints)
3059		return status;
3060
3061	/* constraints need specific supporting methods */
3062	if (ops->set_voltage || ops->set_voltage_sel) {
3063		status = device_create_file(dev, &dev_attr_min_microvolts);
3064		if (status < 0)
3065			return status;
3066		status = device_create_file(dev, &dev_attr_max_microvolts);
3067		if (status < 0)
3068			return status;
3069	}
3070	if (ops->set_current_limit) {
3071		status = device_create_file(dev, &dev_attr_min_microamps);
3072		if (status < 0)
3073			return status;
3074		status = device_create_file(dev, &dev_attr_max_microamps);
3075		if (status < 0)
3076			return status;
3077	}
3078
3079	status = device_create_file(dev, &dev_attr_suspend_standby_state);
3080	if (status < 0)
3081		return status;
3082	status = device_create_file(dev, &dev_attr_suspend_mem_state);
3083	if (status < 0)
3084		return status;
3085	status = device_create_file(dev, &dev_attr_suspend_disk_state);
3086	if (status < 0)
3087		return status;
3088
3089	if (ops->set_suspend_voltage) {
3090		status = device_create_file(dev,
3091				&dev_attr_suspend_standby_microvolts);
3092		if (status < 0)
3093			return status;
3094		status = device_create_file(dev,
3095				&dev_attr_suspend_mem_microvolts);
3096		if (status < 0)
3097			return status;
3098		status = device_create_file(dev,
3099				&dev_attr_suspend_disk_microvolts);
3100		if (status < 0)
3101			return status;
3102	}
3103
3104	if (ops->set_suspend_mode) {
3105		status = device_create_file(dev,
3106				&dev_attr_suspend_standby_mode);
3107		if (status < 0)
3108			return status;
3109		status = device_create_file(dev,
3110				&dev_attr_suspend_mem_mode);
3111		if (status < 0)
3112			return status;
3113		status = device_create_file(dev,
3114				&dev_attr_suspend_disk_mode);
3115		if (status < 0)
3116			return status;
3117	}
3118
3119	return status;
3120}
3121
3122static void rdev_init_debugfs(struct regulator_dev *rdev)
3123{
3124	rdev->debugfs = debugfs_create_dir(rdev_get_name(rdev), debugfs_root);
3125	if (!rdev->debugfs) {
3126		rdev_warn(rdev, "Failed to create debugfs directory\n");
3127		return;
3128	}
3129
3130	debugfs_create_u32("use_count", 0444, rdev->debugfs,
3131			   &rdev->use_count);
3132	debugfs_create_u32("open_count", 0444, rdev->debugfs,
3133			   &rdev->open_count);
3134}
3135
3136/**
3137 * regulator_register - register regulator
3138 * @regulator_desc: regulator to register
3139 * @config: runtime configuration for regulator
3140 *
3141 * Called by regulator drivers to register a regulator.
3142 * Returns 0 on success.
3143 */
3144struct regulator_dev *
3145regulator_register(const struct regulator_desc *regulator_desc,
3146		   const struct regulator_config *config)
3147{
3148	const struct regulation_constraints *constraints = NULL;
3149	const struct regulator_init_data *init_data;
3150	static atomic_t regulator_no = ATOMIC_INIT(0);
3151	struct regulator_dev *rdev;
3152	struct device *dev;
3153	int ret, i;
3154	const char *supply = NULL;
3155
3156	if (regulator_desc == NULL || config == NULL)
3157		return ERR_PTR(-EINVAL);
3158
3159	dev = config->dev;
3160	WARN_ON(!dev);
3161
3162	if (regulator_desc->name == NULL || regulator_desc->ops == NULL)
3163		return ERR_PTR(-EINVAL);
3164
3165	if (regulator_desc->type != REGULATOR_VOLTAGE &&
3166	    regulator_desc->type != REGULATOR_CURRENT)
3167		return ERR_PTR(-EINVAL);
3168
3169	/* Only one of each should be implemented */
3170	WARN_ON(regulator_desc->ops->get_voltage &&
3171		regulator_desc->ops->get_voltage_sel);
3172	WARN_ON(regulator_desc->ops->set_voltage &&
3173		regulator_desc->ops->set_voltage_sel);
3174
3175	/* If we're using selectors we must implement list_voltage. */
3176	if (regulator_desc->ops->get_voltage_sel &&
3177	    !regulator_desc->ops->list_voltage) {
3178		return ERR_PTR(-EINVAL);
3179	}
3180	if (regulator_desc->ops->set_voltage_sel &&
3181	    !regulator_desc->ops->list_voltage) {
3182		return ERR_PTR(-EINVAL);
3183	}
3184
3185	init_data = config->init_data;
3186
3187	rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
3188	if (rdev == NULL)
3189		return ERR_PTR(-ENOMEM);
3190
3191	mutex_lock(&regulator_list_mutex);
3192
3193	mutex_init(&rdev->mutex);
3194	rdev->reg_data = config->driver_data;
3195	rdev->owner = regulator_desc->owner;
3196	rdev->desc = regulator_desc;
3197	if (config->regmap)
3198		rdev->regmap = config->regmap;
3199	else
3200		rdev->regmap = dev_get_regmap(dev, NULL);
3201	INIT_LIST_HEAD(&rdev->consumer_list);
3202	INIT_LIST_HEAD(&rdev->list);
3203	BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
3204	INIT_DELAYED_WORK(&rdev->disable_work, regulator_disable_work);
3205
3206	/* preform any regulator specific init */
3207	if (init_data && init_data->regulator_init) {
3208		ret = init_data->regulator_init(rdev->reg_data);
3209		if (ret < 0)
3210			goto clean;
3211	}
3212
3213	/* register with sysfs */
3214	rdev->dev.class = &regulator_class;
3215	rdev->dev.of_node = config->of_node;
3216	rdev->dev.parent = dev;
3217	dev_set_name(&rdev->dev, "regulator.%d",
3218		     atomic_inc_return(&regulator_no) - 1);
3219	ret = device_register(&rdev->dev);
3220	if (ret != 0) {
3221		put_device(&rdev->dev);
3222		goto clean;
3223	}
3224
3225	dev_set_drvdata(&rdev->dev, rdev);
3226
3227	if (config->ena_gpio) {
3228		ret = gpio_request_one(config->ena_gpio,
3229				       GPIOF_DIR_OUT | config->ena_gpio_flags,
3230				       rdev_get_name(rdev));
3231		if (ret != 0) {
3232			rdev_err(rdev, "Failed to request enable GPIO%d: %d\n",
3233				 config->ena_gpio, ret);
3234			goto clean;
3235		}
3236
3237		rdev->ena_gpio = config->ena_gpio;
3238		rdev->ena_gpio_invert = config->ena_gpio_invert;
3239
3240		if (config->ena_gpio_flags & GPIOF_OUT_INIT_HIGH)
3241			rdev->ena_gpio_state = 1;
3242
3243		if (rdev->ena_gpio_invert)
3244			rdev->ena_gpio_state = !rdev->ena_gpio_state;
3245	}
3246
3247	/* set regulator constraints */
3248	if (init_data)
3249		constraints = &init_data->constraints;
3250
3251	ret = set_machine_constraints(rdev, constraints);
3252	if (ret < 0)
3253		goto scrub;
3254
3255	/* add attributes supported by this regulator */
3256	ret = add_regulator_attributes(rdev);
3257	if (ret < 0)
3258		goto scrub;
3259
3260	if (init_data && init_data->supply_regulator)
3261		supply = init_data->supply_regulator;
3262	else if (regulator_desc->supply_name)
3263		supply = regulator_desc->supply_name;
3264
3265	if (supply) {
3266		struct regulator_dev *r;
3267
3268		r = regulator_dev_lookup(dev, supply, &ret);
3269
3270		if (!r) {
3271			dev_err(dev, "Failed to find supply %s\n", supply);
3272			ret = -EPROBE_DEFER;
3273			goto scrub;
3274		}
3275
3276		ret = set_supply(rdev, r);
3277		if (ret < 0)
3278			goto scrub;
3279
3280		/* Enable supply if rail is enabled */
3281		if (_regulator_is_enabled(rdev)) {
3282			ret = regulator_enable(rdev->supply);
3283			if (ret < 0)
3284				goto scrub;
3285		}
3286	}
3287
3288	/* add consumers devices */
3289	if (init_data) {
3290		for (i = 0; i < init_data->num_consumer_supplies; i++) {
3291			ret = set_consumer_device_supply(rdev,
3292				init_data->consumer_supplies[i].dev_name,
3293				init_data->consumer_supplies[i].supply);
3294			if (ret < 0) {
3295				dev_err(dev, "Failed to set supply %s\n",
3296					init_data->consumer_supplies[i].supply);
3297				goto unset_supplies;
3298			}
3299		}
3300	}
3301
3302	list_add(&rdev->list, &regulator_list);
3303
3304	rdev_init_debugfs(rdev);
3305out:
3306	mutex_unlock(&regulator_list_mutex);
3307	return rdev;
3308
3309unset_supplies:
3310	unset_regulator_supplies(rdev);
3311
3312scrub:
3313	if (rdev->supply)
3314		regulator_put(rdev->supply);
3315	if (rdev->ena_gpio)
3316		gpio_free(rdev->ena_gpio);
3317	kfree(rdev->constraints);
3318	device_unregister(&rdev->dev);
3319	/* device core frees rdev */
3320	rdev = ERR_PTR(ret);
3321	goto out;
3322
3323clean:
3324	kfree(rdev);
3325	rdev = ERR_PTR(ret);
3326	goto out;
3327}
3328EXPORT_SYMBOL_GPL(regulator_register);
3329
3330/**
3331 * regulator_unregister - unregister regulator
3332 * @rdev: regulator to unregister
3333 *
3334 * Called by regulator drivers to unregister a regulator.
3335 */
3336void regulator_unregister(struct regulator_dev *rdev)
3337{
3338	if (rdev == NULL)
3339		return;
3340
3341	if (rdev->supply)
3342		regulator_put(rdev->supply);
3343	mutex_lock(&regulator_list_mutex);
3344	debugfs_remove_recursive(rdev->debugfs);
3345	flush_work_sync(&rdev->disable_work.work);
3346	WARN_ON(rdev->open_count);
3347	unset_regulator_supplies(rdev);
3348	list_del(&rdev->list);
3349	kfree(rdev->constraints);
3350	if (rdev->ena_gpio)
3351		gpio_free(rdev->ena_gpio);
3352	device_unregister(&rdev->dev);
3353	mutex_unlock(&regulator_list_mutex);
3354}
3355EXPORT_SYMBOL_GPL(regulator_unregister);
3356
3357/**
3358 * regulator_suspend_prepare - prepare regulators for system wide suspend
3359 * @state: system suspend state
3360 *
3361 * Configure each regulator with it's suspend operating parameters for state.
3362 * This will usually be called by machine suspend code prior to supending.
3363 */
3364int regulator_suspend_prepare(suspend_state_t state)
3365{
3366	struct regulator_dev *rdev;
3367	int ret = 0;
3368
3369	/* ON is handled by regulator active state */
3370	if (state == PM_SUSPEND_ON)
3371		return -EINVAL;
3372
3373	mutex_lock(&regulator_list_mutex);
3374	list_for_each_entry(rdev, &regulator_list, list) {
3375
3376		mutex_lock(&rdev->mutex);
3377		ret = suspend_prepare(rdev, state);
3378		mutex_unlock(&rdev->mutex);
3379
3380		if (ret < 0) {
3381			rdev_err(rdev, "failed to prepare\n");
3382			goto out;
3383		}
3384	}
3385out:
3386	mutex_unlock(&regulator_list_mutex);
3387	return ret;
3388}
3389EXPORT_SYMBOL_GPL(regulator_suspend_prepare);
3390
3391/**
3392 * regulator_suspend_finish - resume regulators from system wide suspend
3393 *
3394 * Turn on regulators that might be turned off by regulator_suspend_prepare
3395 * and that should be turned on according to the regulators properties.
3396 */
3397int regulator_suspend_finish(void)
3398{
3399	struct regulator_dev *rdev;
3400	int ret = 0, error;
3401
3402	mutex_lock(&regulator_list_mutex);
3403	list_for_each_entry(rdev, &regulator_list, list) {
3404		struct regulator_ops *ops = rdev->desc->ops;
3405
3406		mutex_lock(&rdev->mutex);
3407		if ((rdev->use_count > 0  || rdev->constraints->always_on) &&
3408				ops->enable) {
3409			error = ops->enable(rdev);
3410			if (error)
3411				ret = error;
3412		} else {
3413			if (!has_full_constraints)
3414				goto unlock;
3415			if (!ops->disable)
3416				goto unlock;
3417			if (!_regulator_is_enabled(rdev))
3418				goto unlock;
3419
3420			error = ops->disable(rdev);
3421			if (error)
3422				ret = error;
3423		}
3424unlock:
3425		mutex_unlock(&rdev->mutex);
3426	}
3427	mutex_unlock(&regulator_list_mutex);
3428	return ret;
3429}
3430EXPORT_SYMBOL_GPL(regulator_suspend_finish);
3431
3432/**
3433 * regulator_has_full_constraints - the system has fully specified constraints
3434 *
3435 * Calling this function will cause the regulator API to disable all
3436 * regulators which have a zero use count and don't have an always_on
3437 * constraint in a late_initcall.
3438 *
3439 * The intention is that this will become the default behaviour in a
3440 * future kernel release so users are encouraged to use this facility
3441 * now.
3442 */
3443void regulator_has_full_constraints(void)
3444{
3445	has_full_constraints = 1;
3446}
3447EXPORT_SYMBOL_GPL(regulator_has_full_constraints);
3448
3449/**
3450 * regulator_use_dummy_regulator - Provide a dummy regulator when none is found
3451 *
3452 * Calling this function will cause the regulator API to provide a
3453 * dummy regulator to consumers if no physical regulator is found,
3454 * allowing most consumers to proceed as though a regulator were
3455 * configured.  This allows systems such as those with software
3456 * controllable regulators for the CPU core only to be brought up more
3457 * readily.
3458 */
3459void regulator_use_dummy_regulator(void)
3460{
3461	board_wants_dummy_regulator = true;
3462}
3463EXPORT_SYMBOL_GPL(regulator_use_dummy_regulator);
3464
3465/**
3466 * rdev_get_drvdata - get rdev regulator driver data
3467 * @rdev: regulator
3468 *
3469 * Get rdev regulator driver private data. This call can be used in the
3470 * regulator driver context.
3471 */
3472void *rdev_get_drvdata(struct regulator_dev *rdev)
3473{
3474	return rdev->reg_data;
3475}
3476EXPORT_SYMBOL_GPL(rdev_get_drvdata);
3477
3478/**
3479 * regulator_get_drvdata - get regulator driver data
3480 * @regulator: regulator
3481 *
3482 * Get regulator driver private data. This call can be used in the consumer
3483 * driver context when non API regulator specific functions need to be called.
3484 */
3485void *regulator_get_drvdata(struct regulator *regulator)
3486{
3487	return regulator->rdev->reg_data;
3488}
3489EXPORT_SYMBOL_GPL(regulator_get_drvdata);
3490
3491/**
3492 * regulator_set_drvdata - set regulator driver data
3493 * @regulator: regulator
3494 * @data: data
3495 */
3496void regulator_set_drvdata(struct regulator *regulator, void *data)
3497{
3498	regulator->rdev->reg_data = data;
3499}
3500EXPORT_SYMBOL_GPL(regulator_set_drvdata);
3501
3502/**
3503 * regulator_get_id - get regulator ID
3504 * @rdev: regulator
3505 */
3506int rdev_get_id(struct regulator_dev *rdev)
3507{
3508	return rdev->desc->id;
3509}
3510EXPORT_SYMBOL_GPL(rdev_get_id);
3511
3512struct device *rdev_get_dev(struct regulator_dev *rdev)
3513{
3514	return &rdev->dev;
3515}
3516EXPORT_SYMBOL_GPL(rdev_get_dev);
3517
3518void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
3519{
3520	return reg_init_data->driver_data;
3521}
3522EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
3523
3524#ifdef CONFIG_DEBUG_FS
3525static ssize_t supply_map_read_file(struct file *file, char __user *user_buf,
3526				    size_t count, loff_t *ppos)
3527{
3528	char *buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
3529	ssize_t len, ret = 0;
3530	struct regulator_map *map;
3531
3532	if (!buf)
3533		return -ENOMEM;
3534
3535	list_for_each_entry(map, &regulator_map_list, list) {
3536		len = snprintf(buf + ret, PAGE_SIZE - ret,
3537			       "%s -> %s.%s\n",
3538			       rdev_get_name(map->regulator), map->dev_name,
3539			       map->supply);
3540		if (len >= 0)
3541			ret += len;
3542		if (ret > PAGE_SIZE) {
3543			ret = PAGE_SIZE;
3544			break;
3545		}
3546	}
3547
3548	ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
3549
3550	kfree(buf);
3551
3552	return ret;
3553}
3554#endif
3555
3556static const struct file_operations supply_map_fops = {
3557#ifdef CONFIG_DEBUG_FS
3558	.read = supply_map_read_file,
3559	.llseek = default_llseek,
3560#endif
3561};
3562
3563static int __init regulator_init(void)
3564{
3565	int ret;
3566
3567	ret = class_register(&regulator_class);
3568
3569	debugfs_root = debugfs_create_dir("regulator", NULL);
3570	if (!debugfs_root)
3571		pr_warn("regulator: Failed to create debugfs directory\n");
3572
3573	debugfs_create_file("supply_map", 0444, debugfs_root, NULL,
3574			    &supply_map_fops);
3575
3576	regulator_dummy_init();
3577
3578	return ret;
3579}
3580
3581/* init early to allow our consumers to complete system booting */
3582core_initcall(regulator_init);
3583
3584static int __init regulator_init_complete(void)
3585{
3586	struct regulator_dev *rdev;
3587	struct regulator_ops *ops;
3588	struct regulation_constraints *c;
3589	int enabled, ret;
3590
3591	/*
3592	 * Since DT doesn't provide an idiomatic mechanism for
3593	 * enabling full constraints and since it's much more natural
3594	 * with DT to provide them just assume that a DT enabled
3595	 * system has full constraints.
3596	 */
3597	if (of_have_populated_dt())
3598		has_full_constraints = true;
3599
3600	mutex_lock(&regulator_list_mutex);
3601
3602	/* If we have a full configuration then disable any regulators
3603	 * which are not in use or always_on.  This will become the
3604	 * default behaviour in the future.
3605	 */
3606	list_for_each_entry(rdev, &regulator_list, list) {
3607		ops = rdev->desc->ops;
3608		c = rdev->constraints;
3609
3610		if (!ops->disable || (c && c->always_on))
3611			continue;
3612
3613		mutex_lock(&rdev->mutex);
3614
3615		if (rdev->use_count)
3616			goto unlock;
3617
3618		/* If we can't read the status assume it's on. */
3619		if (ops->is_enabled)
3620			enabled = ops->is_enabled(rdev);
3621		else
3622			enabled = 1;
3623
3624		if (!enabled)
3625			goto unlock;
3626
3627		if (has_full_constraints) {
3628			/* We log since this may kill the system if it
3629			 * goes wrong. */
3630			rdev_info(rdev, "disabling\n");
3631			ret = ops->disable(rdev);
3632			if (ret != 0) {
3633				rdev_err(rdev, "couldn't disable: %d\n", ret);
3634			}
3635		} else {
3636			/* The intention is that in future we will
3637			 * assume that full constraints are provided
3638			 * so warn even if we aren't going to do
3639			 * anything here.
3640			 */
3641			rdev_warn(rdev, "incomplete constraints, leaving on\n");
3642		}
3643
3644unlock:
3645		mutex_unlock(&rdev->mutex);
3646	}
3647
3648	mutex_unlock(&regulator_list_mutex);
3649
3650	return 0;
3651}
3652late_initcall(regulator_init_complete);
3653