core.c revision 69279fb9a95051971ac03e558c4d46e7ba84ab3a
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/device.h>
19#include <linux/err.h>
20#include <linux/mutex.h>
21#include <linux/suspend.h>
22#include <linux/regulator/consumer.h>
23#include <linux/regulator/driver.h>
24#include <linux/regulator/machine.h>
25
26#define REGULATOR_VERSION "0.5"
27
28static DEFINE_MUTEX(regulator_list_mutex);
29static LIST_HEAD(regulator_list);
30static LIST_HEAD(regulator_map_list);
31
32/*
33 * struct regulator_dev
34 *
35 * Voltage / Current regulator class device. One for each regulator.
36 */
37struct regulator_dev {
38	struct regulator_desc *desc;
39	int use_count;
40
41	/* lists we belong to */
42	struct list_head list; /* list of all regulators */
43	struct list_head slist; /* list of supplied regulators */
44
45	/* lists we own */
46	struct list_head consumer_list; /* consumers we supply */
47	struct list_head supply_list; /* regulators we supply */
48
49	struct blocking_notifier_head notifier;
50	struct mutex mutex; /* consumer lock */
51	struct module *owner;
52	struct device dev;
53	struct regulation_constraints *constraints;
54	struct regulator_dev *supply;	/* for tree */
55
56	void *reg_data;		/* regulator_dev data */
57};
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	struct device *dev;
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	int uA_load;
80	int min_uV;
81	int max_uV;
82	int enabled; /* count of client enables */
83	char *supply_name;
84	struct device_attribute dev_attr;
85	struct regulator_dev *rdev;
86};
87
88static int _regulator_is_enabled(struct regulator_dev *rdev);
89static int _regulator_disable(struct regulator_dev *rdev);
90static int _regulator_get_voltage(struct regulator_dev *rdev);
91static int _regulator_get_current_limit(struct regulator_dev *rdev);
92static unsigned int _regulator_get_mode(struct regulator_dev *rdev);
93static void _notifier_call_chain(struct regulator_dev *rdev,
94				  unsigned long event, void *data);
95
96/* gets the regulator for a given consumer device */
97static struct regulator *get_device_regulator(struct device *dev)
98{
99	struct regulator *regulator = NULL;
100	struct regulator_dev *rdev;
101
102	mutex_lock(&regulator_list_mutex);
103	list_for_each_entry(rdev, &regulator_list, list) {
104		mutex_lock(&rdev->mutex);
105		list_for_each_entry(regulator, &rdev->consumer_list, list) {
106			if (regulator->dev == dev) {
107				mutex_unlock(&rdev->mutex);
108				mutex_unlock(&regulator_list_mutex);
109				return regulator;
110			}
111		}
112		mutex_unlock(&rdev->mutex);
113	}
114	mutex_unlock(&regulator_list_mutex);
115	return NULL;
116}
117
118/* Platform voltage constraint check */
119static int regulator_check_voltage(struct regulator_dev *rdev,
120				   int *min_uV, int *max_uV)
121{
122	BUG_ON(*min_uV > *max_uV);
123
124	if (!rdev->constraints) {
125		printk(KERN_ERR "%s: no constraints for %s\n", __func__,
126		       rdev->desc->name);
127		return -ENODEV;
128	}
129	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
130		printk(KERN_ERR "%s: operation not allowed for %s\n",
131		       __func__, rdev->desc->name);
132		return -EPERM;
133	}
134
135	if (*max_uV > rdev->constraints->max_uV)
136		*max_uV = rdev->constraints->max_uV;
137	if (*min_uV < rdev->constraints->min_uV)
138		*min_uV = rdev->constraints->min_uV;
139
140	if (*min_uV > *max_uV)
141		return -EINVAL;
142
143	return 0;
144}
145
146/* current constraint check */
147static int regulator_check_current_limit(struct regulator_dev *rdev,
148					int *min_uA, int *max_uA)
149{
150	BUG_ON(*min_uA > *max_uA);
151
152	if (!rdev->constraints) {
153		printk(KERN_ERR "%s: no constraints for %s\n", __func__,
154		       rdev->desc->name);
155		return -ENODEV;
156	}
157	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_CURRENT)) {
158		printk(KERN_ERR "%s: operation not allowed for %s\n",
159		       __func__, rdev->desc->name);
160		return -EPERM;
161	}
162
163	if (*max_uA > rdev->constraints->max_uA)
164		*max_uA = rdev->constraints->max_uA;
165	if (*min_uA < rdev->constraints->min_uA)
166		*min_uA = rdev->constraints->min_uA;
167
168	if (*min_uA > *max_uA)
169		return -EINVAL;
170
171	return 0;
172}
173
174/* operating mode constraint check */
175static int regulator_check_mode(struct regulator_dev *rdev, int mode)
176{
177	switch (mode) {
178	case REGULATOR_MODE_FAST:
179	case REGULATOR_MODE_NORMAL:
180	case REGULATOR_MODE_IDLE:
181	case REGULATOR_MODE_STANDBY:
182		break;
183	default:
184		return -EINVAL;
185	}
186
187	if (!rdev->constraints) {
188		printk(KERN_ERR "%s: no constraints for %s\n", __func__,
189		       rdev->desc->name);
190		return -ENODEV;
191	}
192	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_MODE)) {
193		printk(KERN_ERR "%s: operation not allowed for %s\n",
194		       __func__, rdev->desc->name);
195		return -EPERM;
196	}
197	if (!(rdev->constraints->valid_modes_mask & mode)) {
198		printk(KERN_ERR "%s: invalid mode %x for %s\n",
199		       __func__, mode, rdev->desc->name);
200		return -EINVAL;
201	}
202	return 0;
203}
204
205/* dynamic regulator mode switching constraint check */
206static int regulator_check_drms(struct regulator_dev *rdev)
207{
208	if (!rdev->constraints) {
209		printk(KERN_ERR "%s: no constraints for %s\n", __func__,
210		       rdev->desc->name);
211		return -ENODEV;
212	}
213	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS)) {
214		printk(KERN_ERR "%s: operation not allowed for %s\n",
215		       __func__, rdev->desc->name);
216		return -EPERM;
217	}
218	return 0;
219}
220
221static ssize_t device_requested_uA_show(struct device *dev,
222			     struct device_attribute *attr, char *buf)
223{
224	struct regulator *regulator;
225
226	regulator = get_device_regulator(dev);
227	if (regulator == NULL)
228		return 0;
229
230	return sprintf(buf, "%d\n", regulator->uA_load);
231}
232
233static ssize_t regulator_uV_show(struct device *dev,
234				struct device_attribute *attr, char *buf)
235{
236	struct regulator_dev *rdev = dev_get_drvdata(dev);
237	ssize_t ret;
238
239	mutex_lock(&rdev->mutex);
240	ret = sprintf(buf, "%d\n", _regulator_get_voltage(rdev));
241	mutex_unlock(&rdev->mutex);
242
243	return ret;
244}
245static DEVICE_ATTR(microvolts, 0444, regulator_uV_show, NULL);
246
247static ssize_t regulator_uA_show(struct device *dev,
248				struct device_attribute *attr, char *buf)
249{
250	struct regulator_dev *rdev = dev_get_drvdata(dev);
251
252	return sprintf(buf, "%d\n", _regulator_get_current_limit(rdev));
253}
254static DEVICE_ATTR(microamps, 0444, regulator_uA_show, NULL);
255
256static ssize_t regulator_name_show(struct device *dev,
257			     struct device_attribute *attr, char *buf)
258{
259	struct regulator_dev *rdev = dev_get_drvdata(dev);
260	const char *name;
261
262	if (rdev->constraints->name)
263		name = rdev->constraints->name;
264	else if (rdev->desc->name)
265		name = rdev->desc->name;
266	else
267		name = "";
268
269	return sprintf(buf, "%s\n", name);
270}
271
272static ssize_t regulator_print_opmode(char *buf, int mode)
273{
274	switch (mode) {
275	case REGULATOR_MODE_FAST:
276		return sprintf(buf, "fast\n");
277	case REGULATOR_MODE_NORMAL:
278		return sprintf(buf, "normal\n");
279	case REGULATOR_MODE_IDLE:
280		return sprintf(buf, "idle\n");
281	case REGULATOR_MODE_STANDBY:
282		return sprintf(buf, "standby\n");
283	}
284	return sprintf(buf, "unknown\n");
285}
286
287static ssize_t regulator_opmode_show(struct device *dev,
288				    struct device_attribute *attr, char *buf)
289{
290	struct regulator_dev *rdev = dev_get_drvdata(dev);
291
292	return regulator_print_opmode(buf, _regulator_get_mode(rdev));
293}
294static DEVICE_ATTR(opmode, 0444, regulator_opmode_show, NULL);
295
296static ssize_t regulator_print_state(char *buf, int state)
297{
298	if (state > 0)
299		return sprintf(buf, "enabled\n");
300	else if (state == 0)
301		return sprintf(buf, "disabled\n");
302	else
303		return sprintf(buf, "unknown\n");
304}
305
306static ssize_t regulator_state_show(struct device *dev,
307				   struct device_attribute *attr, char *buf)
308{
309	struct regulator_dev *rdev = dev_get_drvdata(dev);
310
311	return regulator_print_state(buf, _regulator_is_enabled(rdev));
312}
313static DEVICE_ATTR(state, 0444, regulator_state_show, NULL);
314
315static ssize_t regulator_min_uA_show(struct device *dev,
316				    struct device_attribute *attr, char *buf)
317{
318	struct regulator_dev *rdev = dev_get_drvdata(dev);
319
320	if (!rdev->constraints)
321		return sprintf(buf, "constraint not defined\n");
322
323	return sprintf(buf, "%d\n", rdev->constraints->min_uA);
324}
325static DEVICE_ATTR(min_microamps, 0444, regulator_min_uA_show, NULL);
326
327static ssize_t regulator_max_uA_show(struct device *dev,
328				    struct device_attribute *attr, char *buf)
329{
330	struct regulator_dev *rdev = dev_get_drvdata(dev);
331
332	if (!rdev->constraints)
333		return sprintf(buf, "constraint not defined\n");
334
335	return sprintf(buf, "%d\n", rdev->constraints->max_uA);
336}
337static DEVICE_ATTR(max_microamps, 0444, regulator_max_uA_show, NULL);
338
339static ssize_t regulator_min_uV_show(struct device *dev,
340				    struct device_attribute *attr, char *buf)
341{
342	struct regulator_dev *rdev = dev_get_drvdata(dev);
343
344	if (!rdev->constraints)
345		return sprintf(buf, "constraint not defined\n");
346
347	return sprintf(buf, "%d\n", rdev->constraints->min_uV);
348}
349static DEVICE_ATTR(min_microvolts, 0444, regulator_min_uV_show, NULL);
350
351static ssize_t regulator_max_uV_show(struct device *dev,
352				    struct device_attribute *attr, char *buf)
353{
354	struct regulator_dev *rdev = dev_get_drvdata(dev);
355
356	if (!rdev->constraints)
357		return sprintf(buf, "constraint not defined\n");
358
359	return sprintf(buf, "%d\n", rdev->constraints->max_uV);
360}
361static DEVICE_ATTR(max_microvolts, 0444, regulator_max_uV_show, NULL);
362
363static ssize_t regulator_total_uA_show(struct device *dev,
364				      struct device_attribute *attr, char *buf)
365{
366	struct regulator_dev *rdev = dev_get_drvdata(dev);
367	struct regulator *regulator;
368	int uA = 0;
369
370	mutex_lock(&rdev->mutex);
371	list_for_each_entry(regulator, &rdev->consumer_list, list)
372	    uA += regulator->uA_load;
373	mutex_unlock(&rdev->mutex);
374	return sprintf(buf, "%d\n", uA);
375}
376static DEVICE_ATTR(requested_microamps, 0444, regulator_total_uA_show, NULL);
377
378static ssize_t regulator_num_users_show(struct device *dev,
379				      struct device_attribute *attr, char *buf)
380{
381	struct regulator_dev *rdev = dev_get_drvdata(dev);
382	return sprintf(buf, "%d\n", rdev->use_count);
383}
384
385static ssize_t regulator_type_show(struct device *dev,
386				  struct device_attribute *attr, char *buf)
387{
388	struct regulator_dev *rdev = dev_get_drvdata(dev);
389
390	switch (rdev->desc->type) {
391	case REGULATOR_VOLTAGE:
392		return sprintf(buf, "voltage\n");
393	case REGULATOR_CURRENT:
394		return sprintf(buf, "current\n");
395	}
396	return sprintf(buf, "unknown\n");
397}
398
399static ssize_t regulator_suspend_mem_uV_show(struct device *dev,
400				struct device_attribute *attr, char *buf)
401{
402	struct regulator_dev *rdev = dev_get_drvdata(dev);
403
404	return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
405}
406static DEVICE_ATTR(suspend_mem_microvolts, 0444,
407		regulator_suspend_mem_uV_show, NULL);
408
409static ssize_t regulator_suspend_disk_uV_show(struct device *dev,
410				struct device_attribute *attr, char *buf)
411{
412	struct regulator_dev *rdev = dev_get_drvdata(dev);
413
414	return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
415}
416static DEVICE_ATTR(suspend_disk_microvolts, 0444,
417		regulator_suspend_disk_uV_show, NULL);
418
419static ssize_t regulator_suspend_standby_uV_show(struct device *dev,
420				struct device_attribute *attr, char *buf)
421{
422	struct regulator_dev *rdev = dev_get_drvdata(dev);
423
424	return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
425}
426static DEVICE_ATTR(suspend_standby_microvolts, 0444,
427		regulator_suspend_standby_uV_show, NULL);
428
429static ssize_t regulator_suspend_mem_mode_show(struct device *dev,
430				struct device_attribute *attr, char *buf)
431{
432	struct regulator_dev *rdev = dev_get_drvdata(dev);
433
434	return regulator_print_opmode(buf,
435		rdev->constraints->state_mem.mode);
436}
437static DEVICE_ATTR(suspend_mem_mode, 0444,
438		regulator_suspend_mem_mode_show, NULL);
439
440static ssize_t regulator_suspend_disk_mode_show(struct device *dev,
441				struct device_attribute *attr, char *buf)
442{
443	struct regulator_dev *rdev = dev_get_drvdata(dev);
444
445	return regulator_print_opmode(buf,
446		rdev->constraints->state_disk.mode);
447}
448static DEVICE_ATTR(suspend_disk_mode, 0444,
449		regulator_suspend_disk_mode_show, NULL);
450
451static ssize_t regulator_suspend_standby_mode_show(struct device *dev,
452				struct device_attribute *attr, char *buf)
453{
454	struct regulator_dev *rdev = dev_get_drvdata(dev);
455
456	return regulator_print_opmode(buf,
457		rdev->constraints->state_standby.mode);
458}
459static DEVICE_ATTR(suspend_standby_mode, 0444,
460		regulator_suspend_standby_mode_show, NULL);
461
462static ssize_t regulator_suspend_mem_state_show(struct device *dev,
463				   struct device_attribute *attr, char *buf)
464{
465	struct regulator_dev *rdev = dev_get_drvdata(dev);
466
467	return regulator_print_state(buf,
468			rdev->constraints->state_mem.enabled);
469}
470static DEVICE_ATTR(suspend_mem_state, 0444,
471		regulator_suspend_mem_state_show, NULL);
472
473static ssize_t regulator_suspend_disk_state_show(struct device *dev,
474				   struct device_attribute *attr, char *buf)
475{
476	struct regulator_dev *rdev = dev_get_drvdata(dev);
477
478	return regulator_print_state(buf,
479			rdev->constraints->state_disk.enabled);
480}
481static DEVICE_ATTR(suspend_disk_state, 0444,
482		regulator_suspend_disk_state_show, NULL);
483
484static ssize_t regulator_suspend_standby_state_show(struct device *dev,
485				   struct device_attribute *attr, char *buf)
486{
487	struct regulator_dev *rdev = dev_get_drvdata(dev);
488
489	return regulator_print_state(buf,
490			rdev->constraints->state_standby.enabled);
491}
492static DEVICE_ATTR(suspend_standby_state, 0444,
493		regulator_suspend_standby_state_show, NULL);
494
495
496/*
497 * These are the only attributes are present for all regulators.
498 * Other attributes are a function of regulator functionality.
499 */
500static struct device_attribute regulator_dev_attrs[] = {
501	__ATTR(name, 0444, regulator_name_show, NULL),
502	__ATTR(num_users, 0444, regulator_num_users_show, NULL),
503	__ATTR(type, 0444, regulator_type_show, NULL),
504	__ATTR_NULL,
505};
506
507static void regulator_dev_release(struct device *dev)
508{
509	struct regulator_dev *rdev = dev_get_drvdata(dev);
510	kfree(rdev);
511}
512
513static struct class regulator_class = {
514	.name = "regulator",
515	.dev_release = regulator_dev_release,
516	.dev_attrs = regulator_dev_attrs,
517};
518
519/* Calculate the new optimum regulator operating mode based on the new total
520 * consumer load. All locks held by caller */
521static void drms_uA_update(struct regulator_dev *rdev)
522{
523	struct regulator *sibling;
524	int current_uA = 0, output_uV, input_uV, err;
525	unsigned int mode;
526
527	err = regulator_check_drms(rdev);
528	if (err < 0 || !rdev->desc->ops->get_optimum_mode ||
529	    !rdev->desc->ops->get_voltage || !rdev->desc->ops->set_mode);
530	return;
531
532	/* get output voltage */
533	output_uV = rdev->desc->ops->get_voltage(rdev);
534	if (output_uV <= 0)
535		return;
536
537	/* get input voltage */
538	if (rdev->supply && rdev->supply->desc->ops->get_voltage)
539		input_uV = rdev->supply->desc->ops->get_voltage(rdev->supply);
540	else
541		input_uV = rdev->constraints->input_uV;
542	if (input_uV <= 0)
543		return;
544
545	/* calc total requested load */
546	list_for_each_entry(sibling, &rdev->consumer_list, list)
547	    current_uA += sibling->uA_load;
548
549	/* now get the optimum mode for our new total regulator load */
550	mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
551						  output_uV, current_uA);
552
553	/* check the new mode is allowed */
554	err = regulator_check_mode(rdev, mode);
555	if (err == 0)
556		rdev->desc->ops->set_mode(rdev, mode);
557}
558
559static int suspend_set_state(struct regulator_dev *rdev,
560	struct regulator_state *rstate)
561{
562	int ret = 0;
563
564	/* enable & disable are mandatory for suspend control */
565	if (!rdev->desc->ops->set_suspend_enable ||
566		!rdev->desc->ops->set_suspend_disable) {
567		printk(KERN_ERR "%s: no way to set suspend state\n",
568			__func__);
569		return -EINVAL;
570	}
571
572	if (rstate->enabled)
573		ret = rdev->desc->ops->set_suspend_enable(rdev);
574	else
575		ret = rdev->desc->ops->set_suspend_disable(rdev);
576	if (ret < 0) {
577		printk(KERN_ERR "%s: failed to enabled/disable\n", __func__);
578		return ret;
579	}
580
581	if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
582		ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
583		if (ret < 0) {
584			printk(KERN_ERR "%s: failed to set voltage\n",
585				__func__);
586			return ret;
587		}
588	}
589
590	if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
591		ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
592		if (ret < 0) {
593			printk(KERN_ERR "%s: failed to set mode\n", __func__);
594			return ret;
595		}
596	}
597	return ret;
598}
599
600/* locks held by caller */
601static int suspend_prepare(struct regulator_dev *rdev, suspend_state_t state)
602{
603	if (!rdev->constraints)
604		return -EINVAL;
605
606	switch (state) {
607	case PM_SUSPEND_STANDBY:
608		return suspend_set_state(rdev,
609			&rdev->constraints->state_standby);
610	case PM_SUSPEND_MEM:
611		return suspend_set_state(rdev,
612			&rdev->constraints->state_mem);
613	case PM_SUSPEND_MAX:
614		return suspend_set_state(rdev,
615			&rdev->constraints->state_disk);
616	default:
617		return -EINVAL;
618	}
619}
620
621static void print_constraints(struct regulator_dev *rdev)
622{
623	struct regulation_constraints *constraints = rdev->constraints;
624	char buf[80];
625	int count;
626
627	if (rdev->desc->type == REGULATOR_VOLTAGE) {
628		if (constraints->min_uV == constraints->max_uV)
629			count = sprintf(buf, "%d mV ",
630					constraints->min_uV / 1000);
631		else
632			count = sprintf(buf, "%d <--> %d mV ",
633					constraints->min_uV / 1000,
634					constraints->max_uV / 1000);
635	} else {
636		if (constraints->min_uA == constraints->max_uA)
637			count = sprintf(buf, "%d mA ",
638					constraints->min_uA / 1000);
639		else
640			count = sprintf(buf, "%d <--> %d mA ",
641					constraints->min_uA / 1000,
642					constraints->max_uA / 1000);
643	}
644	if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
645		count += sprintf(buf + count, "fast ");
646	if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
647		count += sprintf(buf + count, "normal ");
648	if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
649		count += sprintf(buf + count, "idle ");
650	if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
651		count += sprintf(buf + count, "standby");
652
653	printk(KERN_INFO "regulator: %s: %s\n", rdev->desc->name, buf);
654}
655
656/**
657 * set_machine_constraints - sets regulator constraints
658 * @rdev: regulator source
659 *
660 * Allows platform initialisation code to define and constrain
661 * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
662 * Constraints *must* be set by platform code in order for some
663 * regulator operations to proceed i.e. set_voltage, set_current_limit,
664 * set_mode.
665 */
666static int set_machine_constraints(struct regulator_dev *rdev,
667	struct regulation_constraints *constraints)
668{
669	int ret = 0;
670	const char *name;
671	struct regulator_ops *ops = rdev->desc->ops;
672
673	if (constraints->name)
674		name = constraints->name;
675	else if (rdev->desc->name)
676		name = rdev->desc->name;
677	else
678		name = "regulator";
679
680	rdev->constraints = constraints;
681
682	/* do we need to apply the constraint voltage */
683	if (rdev->constraints->apply_uV &&
684		rdev->constraints->min_uV == rdev->constraints->max_uV &&
685		ops->set_voltage) {
686		ret = ops->set_voltage(rdev,
687			rdev->constraints->min_uV, rdev->constraints->max_uV);
688			if (ret < 0) {
689				printk(KERN_ERR "%s: failed to apply %duV constraint to %s\n",
690				       __func__,
691				       rdev->constraints->min_uV, name);
692				rdev->constraints = NULL;
693				goto out;
694			}
695	}
696
697	/* are we enabled at boot time by firmware / bootloader */
698	if (rdev->constraints->boot_on)
699		rdev->use_count = 1;
700
701	/* do we need to setup our suspend state */
702	if (constraints->initial_state) {
703		ret = suspend_prepare(rdev, constraints->initial_state);
704		if (ret < 0) {
705			printk(KERN_ERR "%s: failed to set suspend state for %s\n",
706			       __func__, name);
707			rdev->constraints = NULL;
708			goto out;
709		}
710	}
711
712	/* if always_on is set then turn the regulator on if it's not
713	 * already on. */
714	if (constraints->always_on && ops->enable &&
715	    ((ops->is_enabled && !ops->is_enabled(rdev)) ||
716	     (!ops->is_enabled && !constraints->boot_on))) {
717		ret = ops->enable(rdev);
718		if (ret < 0) {
719			printk(KERN_ERR "%s: failed to enable %s\n",
720			       __func__, name);
721			rdev->constraints = NULL;
722			goto out;
723		}
724	}
725
726	print_constraints(rdev);
727out:
728	return ret;
729}
730
731/**
732 * set_supply - set regulator supply regulator
733 * @rdev: regulator name
734 * @supply_rdev: supply regulator name
735 *
736 * Called by platform initialisation code to set the supply regulator for this
737 * regulator. This ensures that a regulators supply will also be enabled by the
738 * core if it's child is enabled.
739 */
740static int set_supply(struct regulator_dev *rdev,
741	struct regulator_dev *supply_rdev)
742{
743	int err;
744
745	err = sysfs_create_link(&rdev->dev.kobj, &supply_rdev->dev.kobj,
746				"supply");
747	if (err) {
748		printk(KERN_ERR
749		       "%s: could not add device link %s err %d\n",
750		       __func__, supply_rdev->dev.kobj.name, err);
751		       goto out;
752	}
753	rdev->supply = supply_rdev;
754	list_add(&rdev->slist, &supply_rdev->supply_list);
755out:
756	return err;
757}
758
759/**
760 * set_consumer_device_supply: Bind a regulator to a symbolic supply
761 * @rdev:         regulator source
762 * @consumer_dev: device the supply applies to
763 * @supply:       symbolic name for supply
764 *
765 * Allows platform initialisation code to map physical regulator
766 * sources to symbolic names for supplies for use by devices.  Devices
767 * should use these symbolic names to request regulators, avoiding the
768 * need to provide board-specific regulator names as platform data.
769 */
770static int set_consumer_device_supply(struct regulator_dev *rdev,
771	struct device *consumer_dev, const char *supply)
772{
773	struct regulator_map *node;
774
775	if (supply == NULL)
776		return -EINVAL;
777
778	node = kmalloc(sizeof(struct regulator_map), GFP_KERNEL);
779	if (node == NULL)
780		return -ENOMEM;
781
782	node->regulator = rdev;
783	node->dev = consumer_dev;
784	node->supply = supply;
785
786	list_add(&node->list, &regulator_map_list);
787	return 0;
788}
789
790static void unset_consumer_device_supply(struct regulator_dev *rdev,
791	struct device *consumer_dev)
792{
793	struct regulator_map *node, *n;
794
795	list_for_each_entry_safe(node, n, &regulator_map_list, list) {
796		if (rdev == node->regulator &&
797			consumer_dev == node->dev) {
798			list_del(&node->list);
799			kfree(node);
800			return;
801		}
802	}
803}
804
805#define REG_STR_SIZE	32
806
807static struct regulator *create_regulator(struct regulator_dev *rdev,
808					  struct device *dev,
809					  const char *supply_name)
810{
811	struct regulator *regulator;
812	char buf[REG_STR_SIZE];
813	int err, size;
814
815	regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
816	if (regulator == NULL)
817		return NULL;
818
819	mutex_lock(&rdev->mutex);
820	regulator->rdev = rdev;
821	list_add(&regulator->list, &rdev->consumer_list);
822
823	if (dev) {
824		/* create a 'requested_microamps_name' sysfs entry */
825		size = scnprintf(buf, REG_STR_SIZE, "microamps_requested_%s",
826			supply_name);
827		if (size >= REG_STR_SIZE)
828			goto overflow_err;
829
830		regulator->dev = dev;
831		regulator->dev_attr.attr.name = kstrdup(buf, GFP_KERNEL);
832		if (regulator->dev_attr.attr.name == NULL)
833			goto attr_name_err;
834
835		regulator->dev_attr.attr.owner = THIS_MODULE;
836		regulator->dev_attr.attr.mode = 0444;
837		regulator->dev_attr.show = device_requested_uA_show;
838		err = device_create_file(dev, &regulator->dev_attr);
839		if (err < 0) {
840			printk(KERN_WARNING "%s: could not add regulator_dev"
841				" load sysfs\n", __func__);
842			goto attr_name_err;
843		}
844
845		/* also add a link to the device sysfs entry */
846		size = scnprintf(buf, REG_STR_SIZE, "%s-%s",
847				 dev->kobj.name, supply_name);
848		if (size >= REG_STR_SIZE)
849			goto attr_err;
850
851		regulator->supply_name = kstrdup(buf, GFP_KERNEL);
852		if (regulator->supply_name == NULL)
853			goto attr_err;
854
855		err = sysfs_create_link(&rdev->dev.kobj, &dev->kobj,
856					buf);
857		if (err) {
858			printk(KERN_WARNING
859			       "%s: could not add device link %s err %d\n",
860			       __func__, dev->kobj.name, err);
861			device_remove_file(dev, &regulator->dev_attr);
862			goto link_name_err;
863		}
864	}
865	mutex_unlock(&rdev->mutex);
866	return regulator;
867link_name_err:
868	kfree(regulator->supply_name);
869attr_err:
870	device_remove_file(regulator->dev, &regulator->dev_attr);
871attr_name_err:
872	kfree(regulator->dev_attr.attr.name);
873overflow_err:
874	list_del(&regulator->list);
875	kfree(regulator);
876	mutex_unlock(&rdev->mutex);
877	return NULL;
878}
879
880/**
881 * regulator_get - lookup and obtain a reference to a regulator.
882 * @dev: device for regulator "consumer"
883 * @id: Supply name or regulator ID.
884 *
885 * Returns a struct regulator corresponding to the regulator producer,
886 * or IS_ERR() condition containing errno.  Use of supply names
887 * configured via regulator_set_device_supply() is strongly
888 * encouraged.
889 */
890struct regulator *regulator_get(struct device *dev, const char *id)
891{
892	struct regulator_dev *rdev;
893	struct regulator_map *map;
894	struct regulator *regulator = ERR_PTR(-ENODEV);
895
896	if (id == NULL) {
897		printk(KERN_ERR "regulator: get() with no identifier\n");
898		return regulator;
899	}
900
901	mutex_lock(&regulator_list_mutex);
902
903	list_for_each_entry(map, &regulator_map_list, list) {
904		if (dev == map->dev &&
905		    strcmp(map->supply, id) == 0) {
906			rdev = map->regulator;
907			goto found;
908		}
909	}
910	printk(KERN_ERR "regulator: Unable to get requested regulator: %s\n",
911	       id);
912	mutex_unlock(&regulator_list_mutex);
913	return regulator;
914
915found:
916	if (!try_module_get(rdev->owner))
917		goto out;
918
919	regulator = create_regulator(rdev, dev, id);
920	if (regulator == NULL) {
921		regulator = ERR_PTR(-ENOMEM);
922		module_put(rdev->owner);
923	}
924
925out:
926	mutex_unlock(&regulator_list_mutex);
927	return regulator;
928}
929EXPORT_SYMBOL_GPL(regulator_get);
930
931/**
932 * regulator_put - "free" the regulator source
933 * @regulator: regulator source
934 *
935 * Note: drivers must ensure that all regulator_enable calls made on this
936 * regulator source are balanced by regulator_disable calls prior to calling
937 * this function.
938 */
939void regulator_put(struct regulator *regulator)
940{
941	struct regulator_dev *rdev;
942
943	if (regulator == NULL || IS_ERR(regulator))
944		return;
945
946	mutex_lock(&regulator_list_mutex);
947	rdev = regulator->rdev;
948
949	if (WARN(regulator->enabled, "Releasing supply %s while enabled\n",
950			       regulator->supply_name))
951		_regulator_disable(rdev);
952
953	/* remove any sysfs entries */
954	if (regulator->dev) {
955		sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
956		kfree(regulator->supply_name);
957		device_remove_file(regulator->dev, &regulator->dev_attr);
958		kfree(regulator->dev_attr.attr.name);
959	}
960	list_del(&regulator->list);
961	kfree(regulator);
962
963	module_put(rdev->owner);
964	mutex_unlock(&regulator_list_mutex);
965}
966EXPORT_SYMBOL_GPL(regulator_put);
967
968/* locks held by regulator_enable() */
969static int _regulator_enable(struct regulator_dev *rdev)
970{
971	int ret = -EINVAL;
972
973	if (!rdev->constraints) {
974		printk(KERN_ERR "%s: %s has no constraints\n",
975		       __func__, rdev->desc->name);
976		return ret;
977	}
978
979	/* do we need to enable the supply regulator first */
980	if (rdev->supply) {
981		ret = _regulator_enable(rdev->supply);
982		if (ret < 0) {
983			printk(KERN_ERR "%s: failed to enable %s: %d\n",
984			       __func__, rdev->desc->name, ret);
985			return ret;
986		}
987	}
988
989	/* check voltage and requested load before enabling */
990	if (rdev->desc->ops->enable) {
991
992		if (rdev->constraints &&
993			(rdev->constraints->valid_ops_mask &
994			REGULATOR_CHANGE_DRMS))
995			drms_uA_update(rdev);
996
997		ret = rdev->desc->ops->enable(rdev);
998		if (ret < 0) {
999			printk(KERN_ERR "%s: failed to enable %s: %d\n",
1000			       __func__, rdev->desc->name, ret);
1001			return ret;
1002		}
1003		rdev->use_count++;
1004		return ret;
1005	}
1006
1007	return ret;
1008}
1009
1010/**
1011 * regulator_enable - enable regulator output
1012 * @regulator: regulator source
1013 *
1014 * Enable the regulator output at the predefined voltage or current value.
1015 * NOTE: the output value can be set by other drivers, boot loader or may be
1016 * hardwired in the regulator.  Calls to regulator_enable() must be balanced
1017 * with calls to regulator_disable().
1018 */
1019int regulator_enable(struct regulator *regulator)
1020{
1021	struct regulator_dev *rdev = regulator->rdev;
1022	int ret = 0;
1023
1024	mutex_lock(&rdev->mutex);
1025	if (regulator->enabled == 0)
1026		ret = _regulator_enable(rdev);
1027	else if (regulator->enabled < 0)
1028		ret = -EIO;
1029	if (ret == 0)
1030		regulator->enabled++;
1031	mutex_unlock(&rdev->mutex);
1032	return ret;
1033}
1034EXPORT_SYMBOL_GPL(regulator_enable);
1035
1036/* locks held by regulator_disable() */
1037static int _regulator_disable(struct regulator_dev *rdev)
1038{
1039	int ret = 0;
1040
1041	/* are we the last user and permitted to disable ? */
1042	if (rdev->use_count == 1 && !rdev->constraints->always_on) {
1043
1044		/* we are last user */
1045		if (rdev->desc->ops->disable) {
1046			ret = rdev->desc->ops->disable(rdev);
1047			if (ret < 0) {
1048				printk(KERN_ERR "%s: failed to disable %s\n",
1049				       __func__, rdev->desc->name);
1050				return ret;
1051			}
1052		}
1053
1054		/* decrease our supplies ref count and disable if required */
1055		if (rdev->supply)
1056			_regulator_disable(rdev->supply);
1057
1058		rdev->use_count = 0;
1059	} else if (rdev->use_count > 1) {
1060
1061		if (rdev->constraints &&
1062			(rdev->constraints->valid_ops_mask &
1063			REGULATOR_CHANGE_DRMS))
1064			drms_uA_update(rdev);
1065
1066		rdev->use_count--;
1067	}
1068	return ret;
1069}
1070
1071/**
1072 * regulator_disable - disable regulator output
1073 * @regulator: regulator source
1074 *
1075 * Disable the regulator output voltage or current.
1076 *
1077 * NOTE: this will only disable the regulator output if no other consumer
1078 * devices have it enabled.  Calls to regulator_enable() must be balanced with
1079 * calls to regulator_disable().
1080 */
1081int regulator_disable(struct regulator *regulator)
1082{
1083	struct regulator_dev *rdev = regulator->rdev;
1084	int ret = 0;
1085
1086	mutex_lock(&rdev->mutex);
1087	if (regulator->enabled == 1) {
1088		ret = _regulator_disable(rdev);
1089		if (ret == 0)
1090			regulator->uA_load = 0;
1091	} else if (WARN(regulator->enabled <= 0,
1092			"unbalanced disables for supply %s\n",
1093			regulator->supply_name))
1094		ret = -EIO;
1095	if (ret == 0)
1096		regulator->enabled--;
1097	mutex_unlock(&rdev->mutex);
1098	return ret;
1099}
1100EXPORT_SYMBOL_GPL(regulator_disable);
1101
1102/* locks held by regulator_force_disable() */
1103static int _regulator_force_disable(struct regulator_dev *rdev)
1104{
1105	int ret = 0;
1106
1107	/* force disable */
1108	if (rdev->desc->ops->disable) {
1109		/* ah well, who wants to live forever... */
1110		ret = rdev->desc->ops->disable(rdev);
1111		if (ret < 0) {
1112			printk(KERN_ERR "%s: failed to force disable %s\n",
1113			       __func__, rdev->desc->name);
1114			return ret;
1115		}
1116		/* notify other consumers that power has been forced off */
1117		_notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE,
1118			NULL);
1119	}
1120
1121	/* decrease our supplies ref count and disable if required */
1122	if (rdev->supply)
1123		_regulator_disable(rdev->supply);
1124
1125	rdev->use_count = 0;
1126	return ret;
1127}
1128
1129/**
1130 * regulator_force_disable - force disable regulator output
1131 * @regulator: regulator source
1132 *
1133 * Forcibly disable the regulator output voltage or current.
1134 * NOTE: this *will* disable the regulator output even if other consumer
1135 * devices have it enabled. This should be used for situations when device
1136 * damage will likely occur if the regulator is not disabled (e.g. over temp).
1137 */
1138int regulator_force_disable(struct regulator *regulator)
1139{
1140	int ret;
1141
1142	mutex_lock(&regulator->rdev->mutex);
1143	regulator->enabled = 0;
1144	regulator->uA_load = 0;
1145	ret = _regulator_force_disable(regulator->rdev);
1146	mutex_unlock(&regulator->rdev->mutex);
1147	return ret;
1148}
1149EXPORT_SYMBOL_GPL(regulator_force_disable);
1150
1151static int _regulator_is_enabled(struct regulator_dev *rdev)
1152{
1153	int ret;
1154
1155	mutex_lock(&rdev->mutex);
1156
1157	/* sanity check */
1158	if (!rdev->desc->ops->is_enabled) {
1159		ret = -EINVAL;
1160		goto out;
1161	}
1162
1163	ret = rdev->desc->ops->is_enabled(rdev);
1164out:
1165	mutex_unlock(&rdev->mutex);
1166	return ret;
1167}
1168
1169/**
1170 * regulator_is_enabled - is the regulator output enabled
1171 * @regulator: regulator source
1172 *
1173 * Returns positive if the regulator driver backing the source/client
1174 * has requested that the device be enabled, zero if it hasn't, else a
1175 * negative errno code.
1176 *
1177 * Note that the device backing this regulator handle can have multiple
1178 * users, so it might be enabled even if regulator_enable() was never
1179 * called for this particular source.
1180 */
1181int regulator_is_enabled(struct regulator *regulator)
1182{
1183	return _regulator_is_enabled(regulator->rdev);
1184}
1185EXPORT_SYMBOL_GPL(regulator_is_enabled);
1186
1187/**
1188 * regulator_set_voltage - set regulator output voltage
1189 * @regulator: regulator source
1190 * @min_uV: Minimum required voltage in uV
1191 * @max_uV: Maximum acceptable voltage in uV
1192 *
1193 * Sets a voltage regulator to the desired output voltage. This can be set
1194 * during any regulator state. IOW, regulator can be disabled or enabled.
1195 *
1196 * If the regulator is enabled then the voltage will change to the new value
1197 * immediately otherwise if the regulator is disabled the regulator will
1198 * output at the new voltage when enabled.
1199 *
1200 * NOTE: If the regulator is shared between several devices then the lowest
1201 * request voltage that meets the system constraints will be used.
1202 * Regulator system constraints must be set for this regulator before
1203 * calling this function otherwise this call will fail.
1204 */
1205int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
1206{
1207	struct regulator_dev *rdev = regulator->rdev;
1208	int ret;
1209
1210	mutex_lock(&rdev->mutex);
1211
1212	/* sanity check */
1213	if (!rdev->desc->ops->set_voltage) {
1214		ret = -EINVAL;
1215		goto out;
1216	}
1217
1218	/* constraints check */
1219	ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
1220	if (ret < 0)
1221		goto out;
1222	regulator->min_uV = min_uV;
1223	regulator->max_uV = max_uV;
1224	ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV);
1225
1226out:
1227	mutex_unlock(&rdev->mutex);
1228	return ret;
1229}
1230EXPORT_SYMBOL_GPL(regulator_set_voltage);
1231
1232static int _regulator_get_voltage(struct regulator_dev *rdev)
1233{
1234	/* sanity check */
1235	if (rdev->desc->ops->get_voltage)
1236		return rdev->desc->ops->get_voltage(rdev);
1237	else
1238		return -EINVAL;
1239}
1240
1241/**
1242 * regulator_get_voltage - get regulator output voltage
1243 * @regulator: regulator source
1244 *
1245 * This returns the current regulator voltage in uV.
1246 *
1247 * NOTE: If the regulator is disabled it will return the voltage value. This
1248 * function should not be used to determine regulator state.
1249 */
1250int regulator_get_voltage(struct regulator *regulator)
1251{
1252	int ret;
1253
1254	mutex_lock(&regulator->rdev->mutex);
1255
1256	ret = _regulator_get_voltage(regulator->rdev);
1257
1258	mutex_unlock(&regulator->rdev->mutex);
1259
1260	return ret;
1261}
1262EXPORT_SYMBOL_GPL(regulator_get_voltage);
1263
1264/**
1265 * regulator_set_current_limit - set regulator output current limit
1266 * @regulator: regulator source
1267 * @min_uA: Minimuum supported current in uA
1268 * @max_uA: Maximum supported current in uA
1269 *
1270 * Sets current sink to the desired output current. This can be set during
1271 * any regulator state. IOW, regulator can be disabled or enabled.
1272 *
1273 * If the regulator is enabled then the current will change to the new value
1274 * immediately otherwise if the regulator is disabled the regulator will
1275 * output at the new current when enabled.
1276 *
1277 * NOTE: Regulator system constraints must be set for this regulator before
1278 * calling this function otherwise this call will fail.
1279 */
1280int regulator_set_current_limit(struct regulator *regulator,
1281			       int min_uA, int max_uA)
1282{
1283	struct regulator_dev *rdev = regulator->rdev;
1284	int ret;
1285
1286	mutex_lock(&rdev->mutex);
1287
1288	/* sanity check */
1289	if (!rdev->desc->ops->set_current_limit) {
1290		ret = -EINVAL;
1291		goto out;
1292	}
1293
1294	/* constraints check */
1295	ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
1296	if (ret < 0)
1297		goto out;
1298
1299	ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
1300out:
1301	mutex_unlock(&rdev->mutex);
1302	return ret;
1303}
1304EXPORT_SYMBOL_GPL(regulator_set_current_limit);
1305
1306static int _regulator_get_current_limit(struct regulator_dev *rdev)
1307{
1308	int ret;
1309
1310	mutex_lock(&rdev->mutex);
1311
1312	/* sanity check */
1313	if (!rdev->desc->ops->get_current_limit) {
1314		ret = -EINVAL;
1315		goto out;
1316	}
1317
1318	ret = rdev->desc->ops->get_current_limit(rdev);
1319out:
1320	mutex_unlock(&rdev->mutex);
1321	return ret;
1322}
1323
1324/**
1325 * regulator_get_current_limit - get regulator output current
1326 * @regulator: regulator source
1327 *
1328 * This returns the current supplied by the specified current sink in uA.
1329 *
1330 * NOTE: If the regulator is disabled it will return the current value. This
1331 * function should not be used to determine regulator state.
1332 */
1333int regulator_get_current_limit(struct regulator *regulator)
1334{
1335	return _regulator_get_current_limit(regulator->rdev);
1336}
1337EXPORT_SYMBOL_GPL(regulator_get_current_limit);
1338
1339/**
1340 * regulator_set_mode - set regulator operating mode
1341 * @regulator: regulator source
1342 * @mode: operating mode - one of the REGULATOR_MODE constants
1343 *
1344 * Set regulator operating mode to increase regulator efficiency or improve
1345 * regulation performance.
1346 *
1347 * NOTE: Regulator system constraints must be set for this regulator before
1348 * calling this function otherwise this call will fail.
1349 */
1350int regulator_set_mode(struct regulator *regulator, unsigned int mode)
1351{
1352	struct regulator_dev *rdev = regulator->rdev;
1353	int ret;
1354
1355	mutex_lock(&rdev->mutex);
1356
1357	/* sanity check */
1358	if (!rdev->desc->ops->set_mode) {
1359		ret = -EINVAL;
1360		goto out;
1361	}
1362
1363	/* constraints check */
1364	ret = regulator_check_mode(rdev, mode);
1365	if (ret < 0)
1366		goto out;
1367
1368	ret = rdev->desc->ops->set_mode(rdev, mode);
1369out:
1370	mutex_unlock(&rdev->mutex);
1371	return ret;
1372}
1373EXPORT_SYMBOL_GPL(regulator_set_mode);
1374
1375static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
1376{
1377	int ret;
1378
1379	mutex_lock(&rdev->mutex);
1380
1381	/* sanity check */
1382	if (!rdev->desc->ops->get_mode) {
1383		ret = -EINVAL;
1384		goto out;
1385	}
1386
1387	ret = rdev->desc->ops->get_mode(rdev);
1388out:
1389	mutex_unlock(&rdev->mutex);
1390	return ret;
1391}
1392
1393/**
1394 * regulator_get_mode - get regulator operating mode
1395 * @regulator: regulator source
1396 *
1397 * Get the current regulator operating mode.
1398 */
1399unsigned int regulator_get_mode(struct regulator *regulator)
1400{
1401	return _regulator_get_mode(regulator->rdev);
1402}
1403EXPORT_SYMBOL_GPL(regulator_get_mode);
1404
1405/**
1406 * regulator_set_optimum_mode - set regulator optimum operating mode
1407 * @regulator: regulator source
1408 * @uA_load: load current
1409 *
1410 * Notifies the regulator core of a new device load. This is then used by
1411 * DRMS (if enabled by constraints) to set the most efficient regulator
1412 * operating mode for the new regulator loading.
1413 *
1414 * Consumer devices notify their supply regulator of the maximum power
1415 * they will require (can be taken from device datasheet in the power
1416 * consumption tables) when they change operational status and hence power
1417 * state. Examples of operational state changes that can affect power
1418 * consumption are :-
1419 *
1420 *    o Device is opened / closed.
1421 *    o Device I/O is about to begin or has just finished.
1422 *    o Device is idling in between work.
1423 *
1424 * This information is also exported via sysfs to userspace.
1425 *
1426 * DRMS will sum the total requested load on the regulator and change
1427 * to the most efficient operating mode if platform constraints allow.
1428 *
1429 * Returns the new regulator mode or error.
1430 */
1431int regulator_set_optimum_mode(struct regulator *regulator, int uA_load)
1432{
1433	struct regulator_dev *rdev = regulator->rdev;
1434	struct regulator *consumer;
1435	int ret, output_uV, input_uV, total_uA_load = 0;
1436	unsigned int mode;
1437
1438	mutex_lock(&rdev->mutex);
1439
1440	regulator->uA_load = uA_load;
1441	ret = regulator_check_drms(rdev);
1442	if (ret < 0)
1443		goto out;
1444	ret = -EINVAL;
1445
1446	/* sanity check */
1447	if (!rdev->desc->ops->get_optimum_mode)
1448		goto out;
1449
1450	/* get output voltage */
1451	output_uV = rdev->desc->ops->get_voltage(rdev);
1452	if (output_uV <= 0) {
1453		printk(KERN_ERR "%s: invalid output voltage found for %s\n",
1454			__func__, rdev->desc->name);
1455		goto out;
1456	}
1457
1458	/* get input voltage */
1459	if (rdev->supply && rdev->supply->desc->ops->get_voltage)
1460		input_uV = rdev->supply->desc->ops->get_voltage(rdev->supply);
1461	else
1462		input_uV = rdev->constraints->input_uV;
1463	if (input_uV <= 0) {
1464		printk(KERN_ERR "%s: invalid input voltage found for %s\n",
1465			__func__, rdev->desc->name);
1466		goto out;
1467	}
1468
1469	/* calc total requested load for this regulator */
1470	list_for_each_entry(consumer, &rdev->consumer_list, list)
1471	    total_uA_load += consumer->uA_load;
1472
1473	mode = rdev->desc->ops->get_optimum_mode(rdev,
1474						 input_uV, output_uV,
1475						 total_uA_load);
1476	ret = regulator_check_mode(rdev, mode);
1477	if (ret < 0) {
1478		printk(KERN_ERR "%s: failed to get optimum mode for %s @"
1479			" %d uA %d -> %d uV\n", __func__, rdev->desc->name,
1480			total_uA_load, input_uV, output_uV);
1481		goto out;
1482	}
1483
1484	ret = rdev->desc->ops->set_mode(rdev, mode);
1485	if (ret < 0) {
1486		printk(KERN_ERR "%s: failed to set optimum mode %x for %s\n",
1487			__func__, mode, rdev->desc->name);
1488		goto out;
1489	}
1490	ret = mode;
1491out:
1492	mutex_unlock(&rdev->mutex);
1493	return ret;
1494}
1495EXPORT_SYMBOL_GPL(regulator_set_optimum_mode);
1496
1497/**
1498 * regulator_register_notifier - register regulator event notifier
1499 * @regulator: regulator source
1500 * @nb: notifier block
1501 *
1502 * Register notifier block to receive regulator events.
1503 */
1504int regulator_register_notifier(struct regulator *regulator,
1505			      struct notifier_block *nb)
1506{
1507	return blocking_notifier_chain_register(&regulator->rdev->notifier,
1508						nb);
1509}
1510EXPORT_SYMBOL_GPL(regulator_register_notifier);
1511
1512/**
1513 * regulator_unregister_notifier - unregister regulator event notifier
1514 * @regulator: regulator source
1515 * @nb: notifier block
1516 *
1517 * Unregister regulator event notifier block.
1518 */
1519int regulator_unregister_notifier(struct regulator *regulator,
1520				struct notifier_block *nb)
1521{
1522	return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
1523						  nb);
1524}
1525EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
1526
1527/* notify regulator consumers and downstream regulator consumers */
1528static void _notifier_call_chain(struct regulator_dev *rdev,
1529				  unsigned long event, void *data)
1530{
1531	struct regulator_dev *_rdev;
1532
1533	/* call rdev chain first */
1534	mutex_lock(&rdev->mutex);
1535	blocking_notifier_call_chain(&rdev->notifier, event, NULL);
1536	mutex_unlock(&rdev->mutex);
1537
1538	/* now notify regulator we supply */
1539	list_for_each_entry(_rdev, &rdev->supply_list, slist)
1540		_notifier_call_chain(_rdev, event, data);
1541}
1542
1543/**
1544 * regulator_bulk_get - get multiple regulator consumers
1545 *
1546 * @dev:           Device to supply
1547 * @num_consumers: Number of consumers to register
1548 * @consumers:     Configuration of consumers; clients are stored here.
1549 *
1550 * @return 0 on success, an errno on failure.
1551 *
1552 * This helper function allows drivers to get several regulator
1553 * consumers in one operation.  If any of the regulators cannot be
1554 * acquired then any regulators that were allocated will be freed
1555 * before returning to the caller.
1556 */
1557int regulator_bulk_get(struct device *dev, int num_consumers,
1558		       struct regulator_bulk_data *consumers)
1559{
1560	int i;
1561	int ret;
1562
1563	for (i = 0; i < num_consumers; i++)
1564		consumers[i].consumer = NULL;
1565
1566	for (i = 0; i < num_consumers; i++) {
1567		consumers[i].consumer = regulator_get(dev,
1568						      consumers[i].supply);
1569		if (IS_ERR(consumers[i].consumer)) {
1570			dev_err(dev, "Failed to get supply '%s'\n",
1571				consumers[i].supply);
1572			ret = PTR_ERR(consumers[i].consumer);
1573			consumers[i].consumer = NULL;
1574			goto err;
1575		}
1576	}
1577
1578	return 0;
1579
1580err:
1581	for (i = 0; i < num_consumers && consumers[i].consumer; i++)
1582		regulator_put(consumers[i].consumer);
1583
1584	return ret;
1585}
1586EXPORT_SYMBOL_GPL(regulator_bulk_get);
1587
1588/**
1589 * regulator_bulk_enable - enable multiple regulator consumers
1590 *
1591 * @num_consumers: Number of consumers
1592 * @consumers:     Consumer data; clients are stored here.
1593 * @return         0 on success, an errno on failure
1594 *
1595 * This convenience API allows consumers to enable multiple regulator
1596 * clients in a single API call.  If any consumers cannot be enabled
1597 * then any others that were enabled will be disabled again prior to
1598 * return.
1599 */
1600int regulator_bulk_enable(int num_consumers,
1601			  struct regulator_bulk_data *consumers)
1602{
1603	int i;
1604	int ret;
1605
1606	for (i = 0; i < num_consumers; i++) {
1607		ret = regulator_enable(consumers[i].consumer);
1608		if (ret != 0)
1609			goto err;
1610	}
1611
1612	return 0;
1613
1614err:
1615	printk(KERN_ERR "Failed to enable %s\n", consumers[i].supply);
1616	for (i = 0; i < num_consumers; i++)
1617		regulator_disable(consumers[i].consumer);
1618
1619	return ret;
1620}
1621EXPORT_SYMBOL_GPL(regulator_bulk_enable);
1622
1623/**
1624 * regulator_bulk_disable - disable multiple regulator consumers
1625 *
1626 * @num_consumers: Number of consumers
1627 * @consumers:     Consumer data; clients are stored here.
1628 * @return         0 on success, an errno on failure
1629 *
1630 * This convenience API allows consumers to disable multiple regulator
1631 * clients in a single API call.  If any consumers cannot be enabled
1632 * then any others that were disabled will be disabled again prior to
1633 * return.
1634 */
1635int regulator_bulk_disable(int num_consumers,
1636			   struct regulator_bulk_data *consumers)
1637{
1638	int i;
1639	int ret;
1640
1641	for (i = 0; i < num_consumers; i++) {
1642		ret = regulator_disable(consumers[i].consumer);
1643		if (ret != 0)
1644			goto err;
1645	}
1646
1647	return 0;
1648
1649err:
1650	printk(KERN_ERR "Failed to disable %s\n", consumers[i].supply);
1651	for (i = 0; i < num_consumers; i++)
1652		regulator_enable(consumers[i].consumer);
1653
1654	return ret;
1655}
1656EXPORT_SYMBOL_GPL(regulator_bulk_disable);
1657
1658/**
1659 * regulator_bulk_free - free multiple regulator consumers
1660 *
1661 * @num_consumers: Number of consumers
1662 * @consumers:     Consumer data; clients are stored here.
1663 *
1664 * This convenience API allows consumers to free multiple regulator
1665 * clients in a single API call.
1666 */
1667void regulator_bulk_free(int num_consumers,
1668			 struct regulator_bulk_data *consumers)
1669{
1670	int i;
1671
1672	for (i = 0; i < num_consumers; i++) {
1673		regulator_put(consumers[i].consumer);
1674		consumers[i].consumer = NULL;
1675	}
1676}
1677EXPORT_SYMBOL_GPL(regulator_bulk_free);
1678
1679/**
1680 * regulator_notifier_call_chain - call regulator event notifier
1681 * @rdev: regulator source
1682 * @event: notifier block
1683 * @data: callback-specific data.
1684 *
1685 * Called by regulator drivers to notify clients a regulator event has
1686 * occurred. We also notify regulator clients downstream.
1687 */
1688int regulator_notifier_call_chain(struct regulator_dev *rdev,
1689				  unsigned long event, void *data)
1690{
1691	_notifier_call_chain(rdev, event, data);
1692	return NOTIFY_DONE;
1693
1694}
1695EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
1696
1697/*
1698 * To avoid cluttering sysfs (and memory) with useless state, only
1699 * create attributes that can be meaningfully displayed.
1700 */
1701static int add_regulator_attributes(struct regulator_dev *rdev)
1702{
1703	struct device		*dev = &rdev->dev;
1704	struct regulator_ops	*ops = rdev->desc->ops;
1705	int			status = 0;
1706
1707	/* some attributes need specific methods to be displayed */
1708	if (ops->get_voltage) {
1709		status = device_create_file(dev, &dev_attr_microvolts);
1710		if (status < 0)
1711			return status;
1712	}
1713	if (ops->get_current_limit) {
1714		status = device_create_file(dev, &dev_attr_microamps);
1715		if (status < 0)
1716			return status;
1717	}
1718	if (ops->get_mode) {
1719		status = device_create_file(dev, &dev_attr_opmode);
1720		if (status < 0)
1721			return status;
1722	}
1723	if (ops->is_enabled) {
1724		status = device_create_file(dev, &dev_attr_state);
1725		if (status < 0)
1726			return status;
1727	}
1728
1729	/* some attributes are type-specific */
1730	if (rdev->desc->type == REGULATOR_CURRENT) {
1731		status = device_create_file(dev, &dev_attr_requested_microamps);
1732		if (status < 0)
1733			return status;
1734	}
1735
1736	/* all the other attributes exist to support constraints;
1737	 * don't show them if there are no constraints, or if the
1738	 * relevant supporting methods are missing.
1739	 */
1740	if (!rdev->constraints)
1741		return status;
1742
1743	/* constraints need specific supporting methods */
1744	if (ops->set_voltage) {
1745		status = device_create_file(dev, &dev_attr_min_microvolts);
1746		if (status < 0)
1747			return status;
1748		status = device_create_file(dev, &dev_attr_max_microvolts);
1749		if (status < 0)
1750			return status;
1751	}
1752	if (ops->set_current_limit) {
1753		status = device_create_file(dev, &dev_attr_min_microamps);
1754		if (status < 0)
1755			return status;
1756		status = device_create_file(dev, &dev_attr_max_microamps);
1757		if (status < 0)
1758			return status;
1759	}
1760
1761	/* suspend mode constraints need multiple supporting methods */
1762	if (!(ops->set_suspend_enable && ops->set_suspend_disable))
1763		return status;
1764
1765	status = device_create_file(dev, &dev_attr_suspend_standby_state);
1766	if (status < 0)
1767		return status;
1768	status = device_create_file(dev, &dev_attr_suspend_mem_state);
1769	if (status < 0)
1770		return status;
1771	status = device_create_file(dev, &dev_attr_suspend_disk_state);
1772	if (status < 0)
1773		return status;
1774
1775	if (ops->set_suspend_voltage) {
1776		status = device_create_file(dev,
1777				&dev_attr_suspend_standby_microvolts);
1778		if (status < 0)
1779			return status;
1780		status = device_create_file(dev,
1781				&dev_attr_suspend_mem_microvolts);
1782		if (status < 0)
1783			return status;
1784		status = device_create_file(dev,
1785				&dev_attr_suspend_disk_microvolts);
1786		if (status < 0)
1787			return status;
1788	}
1789
1790	if (ops->set_suspend_mode) {
1791		status = device_create_file(dev,
1792				&dev_attr_suspend_standby_mode);
1793		if (status < 0)
1794			return status;
1795		status = device_create_file(dev,
1796				&dev_attr_suspend_mem_mode);
1797		if (status < 0)
1798			return status;
1799		status = device_create_file(dev,
1800				&dev_attr_suspend_disk_mode);
1801		if (status < 0)
1802			return status;
1803	}
1804
1805	return status;
1806}
1807
1808/**
1809 * regulator_register - register regulator
1810 * @regulator_desc: regulator to register
1811 * @dev: struct device for the regulator
1812 * @driver_data: private regulator data
1813 *
1814 * Called by regulator drivers to register a regulator.
1815 * Returns 0 on success.
1816 */
1817struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc,
1818	struct device *dev, void *driver_data)
1819{
1820	static atomic_t regulator_no = ATOMIC_INIT(0);
1821	struct regulator_dev *rdev;
1822	struct regulator_init_data *init_data = dev->platform_data;
1823	int ret, i;
1824
1825	if (regulator_desc == NULL)
1826		return ERR_PTR(-EINVAL);
1827
1828	if (regulator_desc->name == NULL || regulator_desc->ops == NULL)
1829		return ERR_PTR(-EINVAL);
1830
1831	if (!regulator_desc->type == REGULATOR_VOLTAGE &&
1832	    !regulator_desc->type == REGULATOR_CURRENT)
1833		return ERR_PTR(-EINVAL);
1834
1835	if (!init_data)
1836		return ERR_PTR(-EINVAL);
1837
1838	rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
1839	if (rdev == NULL)
1840		return ERR_PTR(-ENOMEM);
1841
1842	mutex_lock(&regulator_list_mutex);
1843
1844	mutex_init(&rdev->mutex);
1845	rdev->reg_data = driver_data;
1846	rdev->owner = regulator_desc->owner;
1847	rdev->desc = regulator_desc;
1848	INIT_LIST_HEAD(&rdev->consumer_list);
1849	INIT_LIST_HEAD(&rdev->supply_list);
1850	INIT_LIST_HEAD(&rdev->list);
1851	INIT_LIST_HEAD(&rdev->slist);
1852	BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
1853
1854	/* preform any regulator specific init */
1855	if (init_data->regulator_init) {
1856		ret = init_data->regulator_init(rdev->reg_data);
1857		if (ret < 0)
1858			goto clean;
1859	}
1860
1861	/* register with sysfs */
1862	rdev->dev.class = &regulator_class;
1863	rdev->dev.parent = dev;
1864	dev_set_name(&rdev->dev, "regulator.%d",
1865		     atomic_inc_return(&regulator_no) - 1);
1866	ret = device_register(&rdev->dev);
1867	if (ret != 0)
1868		goto clean;
1869
1870	dev_set_drvdata(&rdev->dev, rdev);
1871
1872	/* set regulator constraints */
1873	ret = set_machine_constraints(rdev, &init_data->constraints);
1874	if (ret < 0)
1875		goto scrub;
1876
1877	/* add attributes supported by this regulator */
1878	ret = add_regulator_attributes(rdev);
1879	if (ret < 0)
1880		goto scrub;
1881
1882	/* set supply regulator if it exists */
1883	if (init_data->supply_regulator_dev) {
1884		ret = set_supply(rdev,
1885			dev_get_drvdata(init_data->supply_regulator_dev));
1886		if (ret < 0)
1887			goto scrub;
1888	}
1889
1890	/* add consumers devices */
1891	for (i = 0; i < init_data->num_consumer_supplies; i++) {
1892		ret = set_consumer_device_supply(rdev,
1893			init_data->consumer_supplies[i].dev,
1894			init_data->consumer_supplies[i].supply);
1895		if (ret < 0) {
1896			for (--i; i >= 0; i--)
1897				unset_consumer_device_supply(rdev,
1898					init_data->consumer_supplies[i].dev);
1899			goto scrub;
1900		}
1901	}
1902
1903	list_add(&rdev->list, &regulator_list);
1904out:
1905	mutex_unlock(&regulator_list_mutex);
1906	return rdev;
1907
1908scrub:
1909	device_unregister(&rdev->dev);
1910clean:
1911	kfree(rdev);
1912	rdev = ERR_PTR(ret);
1913	goto out;
1914}
1915EXPORT_SYMBOL_GPL(regulator_register);
1916
1917/**
1918 * regulator_unregister - unregister regulator
1919 * @rdev: regulator to unregister
1920 *
1921 * Called by regulator drivers to unregister a regulator.
1922 */
1923void regulator_unregister(struct regulator_dev *rdev)
1924{
1925	if (rdev == NULL)
1926		return;
1927
1928	mutex_lock(&regulator_list_mutex);
1929	list_del(&rdev->list);
1930	if (rdev->supply)
1931		sysfs_remove_link(&rdev->dev.kobj, "supply");
1932	device_unregister(&rdev->dev);
1933	mutex_unlock(&regulator_list_mutex);
1934}
1935EXPORT_SYMBOL_GPL(regulator_unregister);
1936
1937/**
1938 * regulator_suspend_prepare: prepare regulators for system wide suspend
1939 * @state: system suspend state
1940 *
1941 * Configure each regulator with it's suspend operating parameters for state.
1942 * This will usually be called by machine suspend code prior to supending.
1943 */
1944int regulator_suspend_prepare(suspend_state_t state)
1945{
1946	struct regulator_dev *rdev;
1947	int ret = 0;
1948
1949	/* ON is handled by regulator active state */
1950	if (state == PM_SUSPEND_ON)
1951		return -EINVAL;
1952
1953	mutex_lock(&regulator_list_mutex);
1954	list_for_each_entry(rdev, &regulator_list, list) {
1955
1956		mutex_lock(&rdev->mutex);
1957		ret = suspend_prepare(rdev, state);
1958		mutex_unlock(&rdev->mutex);
1959
1960		if (ret < 0) {
1961			printk(KERN_ERR "%s: failed to prepare %s\n",
1962				__func__, rdev->desc->name);
1963			goto out;
1964		}
1965	}
1966out:
1967	mutex_unlock(&regulator_list_mutex);
1968	return ret;
1969}
1970EXPORT_SYMBOL_GPL(regulator_suspend_prepare);
1971
1972/**
1973 * rdev_get_drvdata - get rdev regulator driver data
1974 * @rdev: regulator
1975 *
1976 * Get rdev regulator driver private data. This call can be used in the
1977 * regulator driver context.
1978 */
1979void *rdev_get_drvdata(struct regulator_dev *rdev)
1980{
1981	return rdev->reg_data;
1982}
1983EXPORT_SYMBOL_GPL(rdev_get_drvdata);
1984
1985/**
1986 * regulator_get_drvdata - get regulator driver data
1987 * @regulator: regulator
1988 *
1989 * Get regulator driver private data. This call can be used in the consumer
1990 * driver context when non API regulator specific functions need to be called.
1991 */
1992void *regulator_get_drvdata(struct regulator *regulator)
1993{
1994	return regulator->rdev->reg_data;
1995}
1996EXPORT_SYMBOL_GPL(regulator_get_drvdata);
1997
1998/**
1999 * regulator_set_drvdata - set regulator driver data
2000 * @regulator: regulator
2001 * @data: data
2002 */
2003void regulator_set_drvdata(struct regulator *regulator, void *data)
2004{
2005	regulator->rdev->reg_data = data;
2006}
2007EXPORT_SYMBOL_GPL(regulator_set_drvdata);
2008
2009/**
2010 * regulator_get_id - get regulator ID
2011 * @rdev: regulator
2012 */
2013int rdev_get_id(struct regulator_dev *rdev)
2014{
2015	return rdev->desc->id;
2016}
2017EXPORT_SYMBOL_GPL(rdev_get_id);
2018
2019struct device *rdev_get_dev(struct regulator_dev *rdev)
2020{
2021	return &rdev->dev;
2022}
2023EXPORT_SYMBOL_GPL(rdev_get_dev);
2024
2025void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
2026{
2027	return reg_init_data->driver_data;
2028}
2029EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
2030
2031static int __init regulator_init(void)
2032{
2033	printk(KERN_INFO "regulator: core version %s\n", REGULATOR_VERSION);
2034	return class_register(&regulator_class);
2035}
2036
2037/* init early to allow our consumers to complete system booting */
2038core_initcall(regulator_init);
2039