core.c revision c8e7e4640facbe99d10a6e262523b25be129b9b9
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 * @constraints: constraints to apply
660 *
661 * Allows platform initialisation code to define and constrain
662 * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
663 * Constraints *must* be set by platform code in order for some
664 * regulator operations to proceed i.e. set_voltage, set_current_limit,
665 * set_mode.
666 */
667static int set_machine_constraints(struct regulator_dev *rdev,
668	struct regulation_constraints *constraints)
669{
670	int ret = 0;
671	const char *name;
672	struct regulator_ops *ops = rdev->desc->ops;
673
674	if (constraints->name)
675		name = constraints->name;
676	else if (rdev->desc->name)
677		name = rdev->desc->name;
678	else
679		name = "regulator";
680
681	rdev->constraints = constraints;
682
683	/* do we need to apply the constraint voltage */
684	if (rdev->constraints->apply_uV &&
685		rdev->constraints->min_uV == rdev->constraints->max_uV &&
686		ops->set_voltage) {
687		ret = ops->set_voltage(rdev,
688			rdev->constraints->min_uV, rdev->constraints->max_uV);
689			if (ret < 0) {
690				printk(KERN_ERR "%s: failed to apply %duV constraint to %s\n",
691				       __func__,
692				       rdev->constraints->min_uV, name);
693				rdev->constraints = NULL;
694				goto out;
695			}
696	}
697
698	/* are we enabled at boot time by firmware / bootloader */
699	if (rdev->constraints->boot_on)
700		rdev->use_count = 1;
701
702	/* do we need to setup our suspend state */
703	if (constraints->initial_state) {
704		ret = suspend_prepare(rdev, constraints->initial_state);
705		if (ret < 0) {
706			printk(KERN_ERR "%s: failed to set suspend state for %s\n",
707			       __func__, name);
708			rdev->constraints = NULL;
709			goto out;
710		}
711	}
712
713	/* if always_on is set then turn the regulator on if it's not
714	 * already on. */
715	if (constraints->always_on && ops->enable &&
716	    ((ops->is_enabled && !ops->is_enabled(rdev)) ||
717	     (!ops->is_enabled && !constraints->boot_on))) {
718		ret = ops->enable(rdev);
719		if (ret < 0) {
720			printk(KERN_ERR "%s: failed to enable %s\n",
721			       __func__, name);
722			rdev->constraints = NULL;
723			goto out;
724		}
725	}
726
727	print_constraints(rdev);
728out:
729	return ret;
730}
731
732/**
733 * set_supply - set regulator supply regulator
734 * @rdev: regulator name
735 * @supply_rdev: supply regulator name
736 *
737 * Called by platform initialisation code to set the supply regulator for this
738 * regulator. This ensures that a regulators supply will also be enabled by the
739 * core if it's child is enabled.
740 */
741static int set_supply(struct regulator_dev *rdev,
742	struct regulator_dev *supply_rdev)
743{
744	int err;
745
746	err = sysfs_create_link(&rdev->dev.kobj, &supply_rdev->dev.kobj,
747				"supply");
748	if (err) {
749		printk(KERN_ERR
750		       "%s: could not add device link %s err %d\n",
751		       __func__, supply_rdev->dev.kobj.name, err);
752		       goto out;
753	}
754	rdev->supply = supply_rdev;
755	list_add(&rdev->slist, &supply_rdev->supply_list);
756out:
757	return err;
758}
759
760/**
761 * set_consumer_device_supply: Bind a regulator to a symbolic supply
762 * @rdev:         regulator source
763 * @consumer_dev: device the supply applies to
764 * @supply:       symbolic name for supply
765 *
766 * Allows platform initialisation code to map physical regulator
767 * sources to symbolic names for supplies for use by devices.  Devices
768 * should use these symbolic names to request regulators, avoiding the
769 * need to provide board-specific regulator names as platform data.
770 */
771static int set_consumer_device_supply(struct regulator_dev *rdev,
772	struct device *consumer_dev, const char *supply)
773{
774	struct regulator_map *node;
775
776	if (supply == NULL)
777		return -EINVAL;
778
779	node = kmalloc(sizeof(struct regulator_map), GFP_KERNEL);
780	if (node == NULL)
781		return -ENOMEM;
782
783	node->regulator = rdev;
784	node->dev = consumer_dev;
785	node->supply = supply;
786
787	list_add(&node->list, &regulator_map_list);
788	return 0;
789}
790
791static void unset_consumer_device_supply(struct regulator_dev *rdev,
792	struct device *consumer_dev)
793{
794	struct regulator_map *node, *n;
795
796	list_for_each_entry_safe(node, n, &regulator_map_list, list) {
797		if (rdev == node->regulator &&
798			consumer_dev == node->dev) {
799			list_del(&node->list);
800			kfree(node);
801			return;
802		}
803	}
804}
805
806#define REG_STR_SIZE	32
807
808static struct regulator *create_regulator(struct regulator_dev *rdev,
809					  struct device *dev,
810					  const char *supply_name)
811{
812	struct regulator *regulator;
813	char buf[REG_STR_SIZE];
814	int err, size;
815
816	regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
817	if (regulator == NULL)
818		return NULL;
819
820	mutex_lock(&rdev->mutex);
821	regulator->rdev = rdev;
822	list_add(&regulator->list, &rdev->consumer_list);
823
824	if (dev) {
825		/* create a 'requested_microamps_name' sysfs entry */
826		size = scnprintf(buf, REG_STR_SIZE, "microamps_requested_%s",
827			supply_name);
828		if (size >= REG_STR_SIZE)
829			goto overflow_err;
830
831		regulator->dev = dev;
832		regulator->dev_attr.attr.name = kstrdup(buf, GFP_KERNEL);
833		if (regulator->dev_attr.attr.name == NULL)
834			goto attr_name_err;
835
836		regulator->dev_attr.attr.owner = THIS_MODULE;
837		regulator->dev_attr.attr.mode = 0444;
838		regulator->dev_attr.show = device_requested_uA_show;
839		err = device_create_file(dev, &regulator->dev_attr);
840		if (err < 0) {
841			printk(KERN_WARNING "%s: could not add regulator_dev"
842				" load sysfs\n", __func__);
843			goto attr_name_err;
844		}
845
846		/* also add a link to the device sysfs entry */
847		size = scnprintf(buf, REG_STR_SIZE, "%s-%s",
848				 dev->kobj.name, supply_name);
849		if (size >= REG_STR_SIZE)
850			goto attr_err;
851
852		regulator->supply_name = kstrdup(buf, GFP_KERNEL);
853		if (regulator->supply_name == NULL)
854			goto attr_err;
855
856		err = sysfs_create_link(&rdev->dev.kobj, &dev->kobj,
857					buf);
858		if (err) {
859			printk(KERN_WARNING
860			       "%s: could not add device link %s err %d\n",
861			       __func__, dev->kobj.name, err);
862			device_remove_file(dev, &regulator->dev_attr);
863			goto link_name_err;
864		}
865	}
866	mutex_unlock(&rdev->mutex);
867	return regulator;
868link_name_err:
869	kfree(regulator->supply_name);
870attr_err:
871	device_remove_file(regulator->dev, &regulator->dev_attr);
872attr_name_err:
873	kfree(regulator->dev_attr.attr.name);
874overflow_err:
875	list_del(&regulator->list);
876	kfree(regulator);
877	mutex_unlock(&rdev->mutex);
878	return NULL;
879}
880
881/**
882 * regulator_get - lookup and obtain a reference to a regulator.
883 * @dev: device for regulator "consumer"
884 * @id: Supply name or regulator ID.
885 *
886 * Returns a struct regulator corresponding to the regulator producer,
887 * or IS_ERR() condition containing errno.  Use of supply names
888 * configured via regulator_set_device_supply() is strongly
889 * encouraged.
890 */
891struct regulator *regulator_get(struct device *dev, const char *id)
892{
893	struct regulator_dev *rdev;
894	struct regulator_map *map;
895	struct regulator *regulator = ERR_PTR(-ENODEV);
896
897	if (id == NULL) {
898		printk(KERN_ERR "regulator: get() with no identifier\n");
899		return regulator;
900	}
901
902	mutex_lock(&regulator_list_mutex);
903
904	list_for_each_entry(map, &regulator_map_list, list) {
905		if (dev == map->dev &&
906		    strcmp(map->supply, id) == 0) {
907			rdev = map->regulator;
908			goto found;
909		}
910	}
911	printk(KERN_ERR "regulator: Unable to get requested regulator: %s\n",
912	       id);
913	mutex_unlock(&regulator_list_mutex);
914	return regulator;
915
916found:
917	if (!try_module_get(rdev->owner))
918		goto out;
919
920	regulator = create_regulator(rdev, dev, id);
921	if (regulator == NULL) {
922		regulator = ERR_PTR(-ENOMEM);
923		module_put(rdev->owner);
924	}
925
926out:
927	mutex_unlock(&regulator_list_mutex);
928	return regulator;
929}
930EXPORT_SYMBOL_GPL(regulator_get);
931
932/**
933 * regulator_put - "free" the regulator source
934 * @regulator: regulator source
935 *
936 * Note: drivers must ensure that all regulator_enable calls made on this
937 * regulator source are balanced by regulator_disable calls prior to calling
938 * this function.
939 */
940void regulator_put(struct regulator *regulator)
941{
942	struct regulator_dev *rdev;
943
944	if (regulator == NULL || IS_ERR(regulator))
945		return;
946
947	mutex_lock(&regulator_list_mutex);
948	rdev = regulator->rdev;
949
950	if (WARN(regulator->enabled, "Releasing supply %s while enabled\n",
951			       regulator->supply_name))
952		_regulator_disable(rdev);
953
954	/* remove any sysfs entries */
955	if (regulator->dev) {
956		sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
957		kfree(regulator->supply_name);
958		device_remove_file(regulator->dev, &regulator->dev_attr);
959		kfree(regulator->dev_attr.attr.name);
960	}
961	list_del(&regulator->list);
962	kfree(regulator);
963
964	module_put(rdev->owner);
965	mutex_unlock(&regulator_list_mutex);
966}
967EXPORT_SYMBOL_GPL(regulator_put);
968
969/* locks held by regulator_enable() */
970static int _regulator_enable(struct regulator_dev *rdev)
971{
972	int ret = -EINVAL;
973
974	if (!rdev->constraints) {
975		printk(KERN_ERR "%s: %s has no constraints\n",
976		       __func__, rdev->desc->name);
977		return ret;
978	}
979
980	/* do we need to enable the supply regulator first */
981	if (rdev->supply) {
982		ret = _regulator_enable(rdev->supply);
983		if (ret < 0) {
984			printk(KERN_ERR "%s: failed to enable %s: %d\n",
985			       __func__, rdev->desc->name, ret);
986			return ret;
987		}
988	}
989
990	/* check voltage and requested load before enabling */
991	if (rdev->desc->ops->enable) {
992
993		if (rdev->constraints &&
994			(rdev->constraints->valid_ops_mask &
995			REGULATOR_CHANGE_DRMS))
996			drms_uA_update(rdev);
997
998		ret = rdev->desc->ops->enable(rdev);
999		if (ret < 0) {
1000			printk(KERN_ERR "%s: failed to enable %s: %d\n",
1001			       __func__, rdev->desc->name, ret);
1002			return ret;
1003		}
1004		rdev->use_count++;
1005		return ret;
1006	}
1007
1008	return ret;
1009}
1010
1011/**
1012 * regulator_enable - enable regulator output
1013 * @regulator: regulator source
1014 *
1015 * Enable the regulator output at the predefined voltage or current value.
1016 * NOTE: the output value can be set by other drivers, boot loader or may be
1017 * hardwired in the regulator.  Calls to regulator_enable() must be balanced
1018 * with calls to regulator_disable().
1019 */
1020int regulator_enable(struct regulator *regulator)
1021{
1022	struct regulator_dev *rdev = regulator->rdev;
1023	int ret = 0;
1024
1025	mutex_lock(&rdev->mutex);
1026	if (regulator->enabled == 0)
1027		ret = _regulator_enable(rdev);
1028	else if (regulator->enabled < 0)
1029		ret = -EIO;
1030	if (ret == 0)
1031		regulator->enabled++;
1032	mutex_unlock(&rdev->mutex);
1033	return ret;
1034}
1035EXPORT_SYMBOL_GPL(regulator_enable);
1036
1037/* locks held by regulator_disable() */
1038static int _regulator_disable(struct regulator_dev *rdev)
1039{
1040	int ret = 0;
1041
1042	/* are we the last user and permitted to disable ? */
1043	if (rdev->use_count == 1 && !rdev->constraints->always_on) {
1044
1045		/* we are last user */
1046		if (rdev->desc->ops->disable) {
1047			ret = rdev->desc->ops->disable(rdev);
1048			if (ret < 0) {
1049				printk(KERN_ERR "%s: failed to disable %s\n",
1050				       __func__, rdev->desc->name);
1051				return ret;
1052			}
1053		}
1054
1055		/* decrease our supplies ref count and disable if required */
1056		if (rdev->supply)
1057			_regulator_disable(rdev->supply);
1058
1059		rdev->use_count = 0;
1060	} else if (rdev->use_count > 1) {
1061
1062		if (rdev->constraints &&
1063			(rdev->constraints->valid_ops_mask &
1064			REGULATOR_CHANGE_DRMS))
1065			drms_uA_update(rdev);
1066
1067		rdev->use_count--;
1068	}
1069	return ret;
1070}
1071
1072/**
1073 * regulator_disable - disable regulator output
1074 * @regulator: regulator source
1075 *
1076 * Disable the regulator output voltage or current.
1077 *
1078 * NOTE: this will only disable the regulator output if no other consumer
1079 * devices have it enabled.  Calls to regulator_enable() must be balanced with
1080 * calls to regulator_disable().
1081 */
1082int regulator_disable(struct regulator *regulator)
1083{
1084	struct regulator_dev *rdev = regulator->rdev;
1085	int ret = 0;
1086
1087	mutex_lock(&rdev->mutex);
1088	if (regulator->enabled == 1) {
1089		ret = _regulator_disable(rdev);
1090		if (ret == 0)
1091			regulator->uA_load = 0;
1092	} else if (WARN(regulator->enabled <= 0,
1093			"unbalanced disables for supply %s\n",
1094			regulator->supply_name))
1095		ret = -EIO;
1096	if (ret == 0)
1097		regulator->enabled--;
1098	mutex_unlock(&rdev->mutex);
1099	return ret;
1100}
1101EXPORT_SYMBOL_GPL(regulator_disable);
1102
1103/* locks held by regulator_force_disable() */
1104static int _regulator_force_disable(struct regulator_dev *rdev)
1105{
1106	int ret = 0;
1107
1108	/* force disable */
1109	if (rdev->desc->ops->disable) {
1110		/* ah well, who wants to live forever... */
1111		ret = rdev->desc->ops->disable(rdev);
1112		if (ret < 0) {
1113			printk(KERN_ERR "%s: failed to force disable %s\n",
1114			       __func__, rdev->desc->name);
1115			return ret;
1116		}
1117		/* notify other consumers that power has been forced off */
1118		_notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE,
1119			NULL);
1120	}
1121
1122	/* decrease our supplies ref count and disable if required */
1123	if (rdev->supply)
1124		_regulator_disable(rdev->supply);
1125
1126	rdev->use_count = 0;
1127	return ret;
1128}
1129
1130/**
1131 * regulator_force_disable - force disable regulator output
1132 * @regulator: regulator source
1133 *
1134 * Forcibly disable the regulator output voltage or current.
1135 * NOTE: this *will* disable the regulator output even if other consumer
1136 * devices have it enabled. This should be used for situations when device
1137 * damage will likely occur if the regulator is not disabled (e.g. over temp).
1138 */
1139int regulator_force_disable(struct regulator *regulator)
1140{
1141	int ret;
1142
1143	mutex_lock(&regulator->rdev->mutex);
1144	regulator->enabled = 0;
1145	regulator->uA_load = 0;
1146	ret = _regulator_force_disable(regulator->rdev);
1147	mutex_unlock(&regulator->rdev->mutex);
1148	return ret;
1149}
1150EXPORT_SYMBOL_GPL(regulator_force_disable);
1151
1152static int _regulator_is_enabled(struct regulator_dev *rdev)
1153{
1154	int ret;
1155
1156	mutex_lock(&rdev->mutex);
1157
1158	/* sanity check */
1159	if (!rdev->desc->ops->is_enabled) {
1160		ret = -EINVAL;
1161		goto out;
1162	}
1163
1164	ret = rdev->desc->ops->is_enabled(rdev);
1165out:
1166	mutex_unlock(&rdev->mutex);
1167	return ret;
1168}
1169
1170/**
1171 * regulator_is_enabled - is the regulator output enabled
1172 * @regulator: regulator source
1173 *
1174 * Returns positive if the regulator driver backing the source/client
1175 * has requested that the device be enabled, zero if it hasn't, else a
1176 * negative errno code.
1177 *
1178 * Note that the device backing this regulator handle can have multiple
1179 * users, so it might be enabled even if regulator_enable() was never
1180 * called for this particular source.
1181 */
1182int regulator_is_enabled(struct regulator *regulator)
1183{
1184	return _regulator_is_enabled(regulator->rdev);
1185}
1186EXPORT_SYMBOL_GPL(regulator_is_enabled);
1187
1188/**
1189 * regulator_set_voltage - set regulator output voltage
1190 * @regulator: regulator source
1191 * @min_uV: Minimum required voltage in uV
1192 * @max_uV: Maximum acceptable voltage in uV
1193 *
1194 * Sets a voltage regulator to the desired output voltage. This can be set
1195 * during any regulator state. IOW, regulator can be disabled or enabled.
1196 *
1197 * If the regulator is enabled then the voltage will change to the new value
1198 * immediately otherwise if the regulator is disabled the regulator will
1199 * output at the new voltage when enabled.
1200 *
1201 * NOTE: If the regulator is shared between several devices then the lowest
1202 * request voltage that meets the system constraints will be used.
1203 * Regulator system constraints must be set for this regulator before
1204 * calling this function otherwise this call will fail.
1205 */
1206int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
1207{
1208	struct regulator_dev *rdev = regulator->rdev;
1209	int ret;
1210
1211	mutex_lock(&rdev->mutex);
1212
1213	/* sanity check */
1214	if (!rdev->desc->ops->set_voltage) {
1215		ret = -EINVAL;
1216		goto out;
1217	}
1218
1219	/* constraints check */
1220	ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
1221	if (ret < 0)
1222		goto out;
1223	regulator->min_uV = min_uV;
1224	regulator->max_uV = max_uV;
1225	ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV);
1226
1227out:
1228	mutex_unlock(&rdev->mutex);
1229	return ret;
1230}
1231EXPORT_SYMBOL_GPL(regulator_set_voltage);
1232
1233static int _regulator_get_voltage(struct regulator_dev *rdev)
1234{
1235	/* sanity check */
1236	if (rdev->desc->ops->get_voltage)
1237		return rdev->desc->ops->get_voltage(rdev);
1238	else
1239		return -EINVAL;
1240}
1241
1242/**
1243 * regulator_get_voltage - get regulator output voltage
1244 * @regulator: regulator source
1245 *
1246 * This returns the current regulator voltage in uV.
1247 *
1248 * NOTE: If the regulator is disabled it will return the voltage value. This
1249 * function should not be used to determine regulator state.
1250 */
1251int regulator_get_voltage(struct regulator *regulator)
1252{
1253	int ret;
1254
1255	mutex_lock(&regulator->rdev->mutex);
1256
1257	ret = _regulator_get_voltage(regulator->rdev);
1258
1259	mutex_unlock(&regulator->rdev->mutex);
1260
1261	return ret;
1262}
1263EXPORT_SYMBOL_GPL(regulator_get_voltage);
1264
1265/**
1266 * regulator_set_current_limit - set regulator output current limit
1267 * @regulator: regulator source
1268 * @min_uA: Minimuum supported current in uA
1269 * @max_uA: Maximum supported current in uA
1270 *
1271 * Sets current sink to the desired output current. This can be set during
1272 * any regulator state. IOW, regulator can be disabled or enabled.
1273 *
1274 * If the regulator is enabled then the current will change to the new value
1275 * immediately otherwise if the regulator is disabled the regulator will
1276 * output at the new current when enabled.
1277 *
1278 * NOTE: Regulator system constraints must be set for this regulator before
1279 * calling this function otherwise this call will fail.
1280 */
1281int regulator_set_current_limit(struct regulator *regulator,
1282			       int min_uA, int max_uA)
1283{
1284	struct regulator_dev *rdev = regulator->rdev;
1285	int ret;
1286
1287	mutex_lock(&rdev->mutex);
1288
1289	/* sanity check */
1290	if (!rdev->desc->ops->set_current_limit) {
1291		ret = -EINVAL;
1292		goto out;
1293	}
1294
1295	/* constraints check */
1296	ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
1297	if (ret < 0)
1298		goto out;
1299
1300	ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
1301out:
1302	mutex_unlock(&rdev->mutex);
1303	return ret;
1304}
1305EXPORT_SYMBOL_GPL(regulator_set_current_limit);
1306
1307static int _regulator_get_current_limit(struct regulator_dev *rdev)
1308{
1309	int ret;
1310
1311	mutex_lock(&rdev->mutex);
1312
1313	/* sanity check */
1314	if (!rdev->desc->ops->get_current_limit) {
1315		ret = -EINVAL;
1316		goto out;
1317	}
1318
1319	ret = rdev->desc->ops->get_current_limit(rdev);
1320out:
1321	mutex_unlock(&rdev->mutex);
1322	return ret;
1323}
1324
1325/**
1326 * regulator_get_current_limit - get regulator output current
1327 * @regulator: regulator source
1328 *
1329 * This returns the current supplied by the specified current sink in uA.
1330 *
1331 * NOTE: If the regulator is disabled it will return the current value. This
1332 * function should not be used to determine regulator state.
1333 */
1334int regulator_get_current_limit(struct regulator *regulator)
1335{
1336	return _regulator_get_current_limit(regulator->rdev);
1337}
1338EXPORT_SYMBOL_GPL(regulator_get_current_limit);
1339
1340/**
1341 * regulator_set_mode - set regulator operating mode
1342 * @regulator: regulator source
1343 * @mode: operating mode - one of the REGULATOR_MODE constants
1344 *
1345 * Set regulator operating mode to increase regulator efficiency or improve
1346 * regulation performance.
1347 *
1348 * NOTE: Regulator system constraints must be set for this regulator before
1349 * calling this function otherwise this call will fail.
1350 */
1351int regulator_set_mode(struct regulator *regulator, unsigned int mode)
1352{
1353	struct regulator_dev *rdev = regulator->rdev;
1354	int ret;
1355
1356	mutex_lock(&rdev->mutex);
1357
1358	/* sanity check */
1359	if (!rdev->desc->ops->set_mode) {
1360		ret = -EINVAL;
1361		goto out;
1362	}
1363
1364	/* constraints check */
1365	ret = regulator_check_mode(rdev, mode);
1366	if (ret < 0)
1367		goto out;
1368
1369	ret = rdev->desc->ops->set_mode(rdev, mode);
1370out:
1371	mutex_unlock(&rdev->mutex);
1372	return ret;
1373}
1374EXPORT_SYMBOL_GPL(regulator_set_mode);
1375
1376static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
1377{
1378	int ret;
1379
1380	mutex_lock(&rdev->mutex);
1381
1382	/* sanity check */
1383	if (!rdev->desc->ops->get_mode) {
1384		ret = -EINVAL;
1385		goto out;
1386	}
1387
1388	ret = rdev->desc->ops->get_mode(rdev);
1389out:
1390	mutex_unlock(&rdev->mutex);
1391	return ret;
1392}
1393
1394/**
1395 * regulator_get_mode - get regulator operating mode
1396 * @regulator: regulator source
1397 *
1398 * Get the current regulator operating mode.
1399 */
1400unsigned int regulator_get_mode(struct regulator *regulator)
1401{
1402	return _regulator_get_mode(regulator->rdev);
1403}
1404EXPORT_SYMBOL_GPL(regulator_get_mode);
1405
1406/**
1407 * regulator_set_optimum_mode - set regulator optimum operating mode
1408 * @regulator: regulator source
1409 * @uA_load: load current
1410 *
1411 * Notifies the regulator core of a new device load. This is then used by
1412 * DRMS (if enabled by constraints) to set the most efficient regulator
1413 * operating mode for the new regulator loading.
1414 *
1415 * Consumer devices notify their supply regulator of the maximum power
1416 * they will require (can be taken from device datasheet in the power
1417 * consumption tables) when they change operational status and hence power
1418 * state. Examples of operational state changes that can affect power
1419 * consumption are :-
1420 *
1421 *    o Device is opened / closed.
1422 *    o Device I/O is about to begin or has just finished.
1423 *    o Device is idling in between work.
1424 *
1425 * This information is also exported via sysfs to userspace.
1426 *
1427 * DRMS will sum the total requested load on the regulator and change
1428 * to the most efficient operating mode if platform constraints allow.
1429 *
1430 * Returns the new regulator mode or error.
1431 */
1432int regulator_set_optimum_mode(struct regulator *regulator, int uA_load)
1433{
1434	struct regulator_dev *rdev = regulator->rdev;
1435	struct regulator *consumer;
1436	int ret, output_uV, input_uV, total_uA_load = 0;
1437	unsigned int mode;
1438
1439	mutex_lock(&rdev->mutex);
1440
1441	regulator->uA_load = uA_load;
1442	ret = regulator_check_drms(rdev);
1443	if (ret < 0)
1444		goto out;
1445	ret = -EINVAL;
1446
1447	/* sanity check */
1448	if (!rdev->desc->ops->get_optimum_mode)
1449		goto out;
1450
1451	/* get output voltage */
1452	output_uV = rdev->desc->ops->get_voltage(rdev);
1453	if (output_uV <= 0) {
1454		printk(KERN_ERR "%s: invalid output voltage found for %s\n",
1455			__func__, rdev->desc->name);
1456		goto out;
1457	}
1458
1459	/* get input voltage */
1460	if (rdev->supply && rdev->supply->desc->ops->get_voltage)
1461		input_uV = rdev->supply->desc->ops->get_voltage(rdev->supply);
1462	else
1463		input_uV = rdev->constraints->input_uV;
1464	if (input_uV <= 0) {
1465		printk(KERN_ERR "%s: invalid input voltage found for %s\n",
1466			__func__, rdev->desc->name);
1467		goto out;
1468	}
1469
1470	/* calc total requested load for this regulator */
1471	list_for_each_entry(consumer, &rdev->consumer_list, list)
1472	    total_uA_load += consumer->uA_load;
1473
1474	mode = rdev->desc->ops->get_optimum_mode(rdev,
1475						 input_uV, output_uV,
1476						 total_uA_load);
1477	ret = regulator_check_mode(rdev, mode);
1478	if (ret < 0) {
1479		printk(KERN_ERR "%s: failed to get optimum mode for %s @"
1480			" %d uA %d -> %d uV\n", __func__, rdev->desc->name,
1481			total_uA_load, input_uV, output_uV);
1482		goto out;
1483	}
1484
1485	ret = rdev->desc->ops->set_mode(rdev, mode);
1486	if (ret < 0) {
1487		printk(KERN_ERR "%s: failed to set optimum mode %x for %s\n",
1488			__func__, mode, rdev->desc->name);
1489		goto out;
1490	}
1491	ret = mode;
1492out:
1493	mutex_unlock(&rdev->mutex);
1494	return ret;
1495}
1496EXPORT_SYMBOL_GPL(regulator_set_optimum_mode);
1497
1498/**
1499 * regulator_register_notifier - register regulator event notifier
1500 * @regulator: regulator source
1501 * @nb: notifier block
1502 *
1503 * Register notifier block to receive regulator events.
1504 */
1505int regulator_register_notifier(struct regulator *regulator,
1506			      struct notifier_block *nb)
1507{
1508	return blocking_notifier_chain_register(&regulator->rdev->notifier,
1509						nb);
1510}
1511EXPORT_SYMBOL_GPL(regulator_register_notifier);
1512
1513/**
1514 * regulator_unregister_notifier - unregister regulator event notifier
1515 * @regulator: regulator source
1516 * @nb: notifier block
1517 *
1518 * Unregister regulator event notifier block.
1519 */
1520int regulator_unregister_notifier(struct regulator *regulator,
1521				struct notifier_block *nb)
1522{
1523	return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
1524						  nb);
1525}
1526EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
1527
1528/* notify regulator consumers and downstream regulator consumers */
1529static void _notifier_call_chain(struct regulator_dev *rdev,
1530				  unsigned long event, void *data)
1531{
1532	struct regulator_dev *_rdev;
1533
1534	/* call rdev chain first */
1535	mutex_lock(&rdev->mutex);
1536	blocking_notifier_call_chain(&rdev->notifier, event, NULL);
1537	mutex_unlock(&rdev->mutex);
1538
1539	/* now notify regulator we supply */
1540	list_for_each_entry(_rdev, &rdev->supply_list, slist)
1541		_notifier_call_chain(_rdev, event, data);
1542}
1543
1544/**
1545 * regulator_bulk_get - get multiple regulator consumers
1546 *
1547 * @dev:           Device to supply
1548 * @num_consumers: Number of consumers to register
1549 * @consumers:     Configuration of consumers; clients are stored here.
1550 *
1551 * @return 0 on success, an errno on failure.
1552 *
1553 * This helper function allows drivers to get several regulator
1554 * consumers in one operation.  If any of the regulators cannot be
1555 * acquired then any regulators that were allocated will be freed
1556 * before returning to the caller.
1557 */
1558int regulator_bulk_get(struct device *dev, int num_consumers,
1559		       struct regulator_bulk_data *consumers)
1560{
1561	int i;
1562	int ret;
1563
1564	for (i = 0; i < num_consumers; i++)
1565		consumers[i].consumer = NULL;
1566
1567	for (i = 0; i < num_consumers; i++) {
1568		consumers[i].consumer = regulator_get(dev,
1569						      consumers[i].supply);
1570		if (IS_ERR(consumers[i].consumer)) {
1571			dev_err(dev, "Failed to get supply '%s'\n",
1572				consumers[i].supply);
1573			ret = PTR_ERR(consumers[i].consumer);
1574			consumers[i].consumer = NULL;
1575			goto err;
1576		}
1577	}
1578
1579	return 0;
1580
1581err:
1582	for (i = 0; i < num_consumers && consumers[i].consumer; i++)
1583		regulator_put(consumers[i].consumer);
1584
1585	return ret;
1586}
1587EXPORT_SYMBOL_GPL(regulator_bulk_get);
1588
1589/**
1590 * regulator_bulk_enable - enable multiple regulator consumers
1591 *
1592 * @num_consumers: Number of consumers
1593 * @consumers:     Consumer data; clients are stored here.
1594 * @return         0 on success, an errno on failure
1595 *
1596 * This convenience API allows consumers to enable multiple regulator
1597 * clients in a single API call.  If any consumers cannot be enabled
1598 * then any others that were enabled will be disabled again prior to
1599 * return.
1600 */
1601int regulator_bulk_enable(int num_consumers,
1602			  struct regulator_bulk_data *consumers)
1603{
1604	int i;
1605	int ret;
1606
1607	for (i = 0; i < num_consumers; i++) {
1608		ret = regulator_enable(consumers[i].consumer);
1609		if (ret != 0)
1610			goto err;
1611	}
1612
1613	return 0;
1614
1615err:
1616	printk(KERN_ERR "Failed to enable %s\n", consumers[i].supply);
1617	for (i = 0; i < num_consumers; i++)
1618		regulator_disable(consumers[i].consumer);
1619
1620	return ret;
1621}
1622EXPORT_SYMBOL_GPL(regulator_bulk_enable);
1623
1624/**
1625 * regulator_bulk_disable - disable multiple regulator consumers
1626 *
1627 * @num_consumers: Number of consumers
1628 * @consumers:     Consumer data; clients are stored here.
1629 * @return         0 on success, an errno on failure
1630 *
1631 * This convenience API allows consumers to disable multiple regulator
1632 * clients in a single API call.  If any consumers cannot be enabled
1633 * then any others that were disabled will be disabled again prior to
1634 * return.
1635 */
1636int regulator_bulk_disable(int num_consumers,
1637			   struct regulator_bulk_data *consumers)
1638{
1639	int i;
1640	int ret;
1641
1642	for (i = 0; i < num_consumers; i++) {
1643		ret = regulator_disable(consumers[i].consumer);
1644		if (ret != 0)
1645			goto err;
1646	}
1647
1648	return 0;
1649
1650err:
1651	printk(KERN_ERR "Failed to disable %s\n", consumers[i].supply);
1652	for (i = 0; i < num_consumers; i++)
1653		regulator_enable(consumers[i].consumer);
1654
1655	return ret;
1656}
1657EXPORT_SYMBOL_GPL(regulator_bulk_disable);
1658
1659/**
1660 * regulator_bulk_free - free multiple regulator consumers
1661 *
1662 * @num_consumers: Number of consumers
1663 * @consumers:     Consumer data; clients are stored here.
1664 *
1665 * This convenience API allows consumers to free multiple regulator
1666 * clients in a single API call.
1667 */
1668void regulator_bulk_free(int num_consumers,
1669			 struct regulator_bulk_data *consumers)
1670{
1671	int i;
1672
1673	for (i = 0; i < num_consumers; i++) {
1674		regulator_put(consumers[i].consumer);
1675		consumers[i].consumer = NULL;
1676	}
1677}
1678EXPORT_SYMBOL_GPL(regulator_bulk_free);
1679
1680/**
1681 * regulator_notifier_call_chain - call regulator event notifier
1682 * @rdev: regulator source
1683 * @event: notifier block
1684 * @data: callback-specific data.
1685 *
1686 * Called by regulator drivers to notify clients a regulator event has
1687 * occurred. We also notify regulator clients downstream.
1688 */
1689int regulator_notifier_call_chain(struct regulator_dev *rdev,
1690				  unsigned long event, void *data)
1691{
1692	_notifier_call_chain(rdev, event, data);
1693	return NOTIFY_DONE;
1694
1695}
1696EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
1697
1698/*
1699 * To avoid cluttering sysfs (and memory) with useless state, only
1700 * create attributes that can be meaningfully displayed.
1701 */
1702static int add_regulator_attributes(struct regulator_dev *rdev)
1703{
1704	struct device		*dev = &rdev->dev;
1705	struct regulator_ops	*ops = rdev->desc->ops;
1706	int			status = 0;
1707
1708	/* some attributes need specific methods to be displayed */
1709	if (ops->get_voltage) {
1710		status = device_create_file(dev, &dev_attr_microvolts);
1711		if (status < 0)
1712			return status;
1713	}
1714	if (ops->get_current_limit) {
1715		status = device_create_file(dev, &dev_attr_microamps);
1716		if (status < 0)
1717			return status;
1718	}
1719	if (ops->get_mode) {
1720		status = device_create_file(dev, &dev_attr_opmode);
1721		if (status < 0)
1722			return status;
1723	}
1724	if (ops->is_enabled) {
1725		status = device_create_file(dev, &dev_attr_state);
1726		if (status < 0)
1727			return status;
1728	}
1729
1730	/* some attributes are type-specific */
1731	if (rdev->desc->type == REGULATOR_CURRENT) {
1732		status = device_create_file(dev, &dev_attr_requested_microamps);
1733		if (status < 0)
1734			return status;
1735	}
1736
1737	/* all the other attributes exist to support constraints;
1738	 * don't show them if there are no constraints, or if the
1739	 * relevant supporting methods are missing.
1740	 */
1741	if (!rdev->constraints)
1742		return status;
1743
1744	/* constraints need specific supporting methods */
1745	if (ops->set_voltage) {
1746		status = device_create_file(dev, &dev_attr_min_microvolts);
1747		if (status < 0)
1748			return status;
1749		status = device_create_file(dev, &dev_attr_max_microvolts);
1750		if (status < 0)
1751			return status;
1752	}
1753	if (ops->set_current_limit) {
1754		status = device_create_file(dev, &dev_attr_min_microamps);
1755		if (status < 0)
1756			return status;
1757		status = device_create_file(dev, &dev_attr_max_microamps);
1758		if (status < 0)
1759			return status;
1760	}
1761
1762	/* suspend mode constraints need multiple supporting methods */
1763	if (!(ops->set_suspend_enable && ops->set_suspend_disable))
1764		return status;
1765
1766	status = device_create_file(dev, &dev_attr_suspend_standby_state);
1767	if (status < 0)
1768		return status;
1769	status = device_create_file(dev, &dev_attr_suspend_mem_state);
1770	if (status < 0)
1771		return status;
1772	status = device_create_file(dev, &dev_attr_suspend_disk_state);
1773	if (status < 0)
1774		return status;
1775
1776	if (ops->set_suspend_voltage) {
1777		status = device_create_file(dev,
1778				&dev_attr_suspend_standby_microvolts);
1779		if (status < 0)
1780			return status;
1781		status = device_create_file(dev,
1782				&dev_attr_suspend_mem_microvolts);
1783		if (status < 0)
1784			return status;
1785		status = device_create_file(dev,
1786				&dev_attr_suspend_disk_microvolts);
1787		if (status < 0)
1788			return status;
1789	}
1790
1791	if (ops->set_suspend_mode) {
1792		status = device_create_file(dev,
1793				&dev_attr_suspend_standby_mode);
1794		if (status < 0)
1795			return status;
1796		status = device_create_file(dev,
1797				&dev_attr_suspend_mem_mode);
1798		if (status < 0)
1799			return status;
1800		status = device_create_file(dev,
1801				&dev_attr_suspend_disk_mode);
1802		if (status < 0)
1803			return status;
1804	}
1805
1806	return status;
1807}
1808
1809/**
1810 * regulator_register - register regulator
1811 * @regulator_desc: regulator to register
1812 * @dev: struct device for the regulator
1813 * @driver_data: private regulator data
1814 *
1815 * Called by regulator drivers to register a regulator.
1816 * Returns 0 on success.
1817 */
1818struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc,
1819	struct device *dev, void *driver_data)
1820{
1821	static atomic_t regulator_no = ATOMIC_INIT(0);
1822	struct regulator_dev *rdev;
1823	struct regulator_init_data *init_data = dev->platform_data;
1824	int ret, i;
1825
1826	if (regulator_desc == NULL)
1827		return ERR_PTR(-EINVAL);
1828
1829	if (regulator_desc->name == NULL || regulator_desc->ops == NULL)
1830		return ERR_PTR(-EINVAL);
1831
1832	if (!regulator_desc->type == REGULATOR_VOLTAGE &&
1833	    !regulator_desc->type == REGULATOR_CURRENT)
1834		return ERR_PTR(-EINVAL);
1835
1836	if (!init_data)
1837		return ERR_PTR(-EINVAL);
1838
1839	rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
1840	if (rdev == NULL)
1841		return ERR_PTR(-ENOMEM);
1842
1843	mutex_lock(&regulator_list_mutex);
1844
1845	mutex_init(&rdev->mutex);
1846	rdev->reg_data = driver_data;
1847	rdev->owner = regulator_desc->owner;
1848	rdev->desc = regulator_desc;
1849	INIT_LIST_HEAD(&rdev->consumer_list);
1850	INIT_LIST_HEAD(&rdev->supply_list);
1851	INIT_LIST_HEAD(&rdev->list);
1852	INIT_LIST_HEAD(&rdev->slist);
1853	BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
1854
1855	/* preform any regulator specific init */
1856	if (init_data->regulator_init) {
1857		ret = init_data->regulator_init(rdev->reg_data);
1858		if (ret < 0)
1859			goto clean;
1860	}
1861
1862	/* register with sysfs */
1863	rdev->dev.class = &regulator_class;
1864	rdev->dev.parent = dev;
1865	dev_set_name(&rdev->dev, "regulator.%d",
1866		     atomic_inc_return(&regulator_no) - 1);
1867	ret = device_register(&rdev->dev);
1868	if (ret != 0)
1869		goto clean;
1870
1871	dev_set_drvdata(&rdev->dev, rdev);
1872
1873	/* set regulator constraints */
1874	ret = set_machine_constraints(rdev, &init_data->constraints);
1875	if (ret < 0)
1876		goto scrub;
1877
1878	/* add attributes supported by this regulator */
1879	ret = add_regulator_attributes(rdev);
1880	if (ret < 0)
1881		goto scrub;
1882
1883	/* set supply regulator if it exists */
1884	if (init_data->supply_regulator_dev) {
1885		ret = set_supply(rdev,
1886			dev_get_drvdata(init_data->supply_regulator_dev));
1887		if (ret < 0)
1888			goto scrub;
1889	}
1890
1891	/* add consumers devices */
1892	for (i = 0; i < init_data->num_consumer_supplies; i++) {
1893		ret = set_consumer_device_supply(rdev,
1894			init_data->consumer_supplies[i].dev,
1895			init_data->consumer_supplies[i].supply);
1896		if (ret < 0) {
1897			for (--i; i >= 0; i--)
1898				unset_consumer_device_supply(rdev,
1899					init_data->consumer_supplies[i].dev);
1900			goto scrub;
1901		}
1902	}
1903
1904	list_add(&rdev->list, &regulator_list);
1905out:
1906	mutex_unlock(&regulator_list_mutex);
1907	return rdev;
1908
1909scrub:
1910	device_unregister(&rdev->dev);
1911clean:
1912	kfree(rdev);
1913	rdev = ERR_PTR(ret);
1914	goto out;
1915}
1916EXPORT_SYMBOL_GPL(regulator_register);
1917
1918/**
1919 * regulator_unregister - unregister regulator
1920 * @rdev: regulator to unregister
1921 *
1922 * Called by regulator drivers to unregister a regulator.
1923 */
1924void regulator_unregister(struct regulator_dev *rdev)
1925{
1926	if (rdev == NULL)
1927		return;
1928
1929	mutex_lock(&regulator_list_mutex);
1930	list_del(&rdev->list);
1931	if (rdev->supply)
1932		sysfs_remove_link(&rdev->dev.kobj, "supply");
1933	device_unregister(&rdev->dev);
1934	mutex_unlock(&regulator_list_mutex);
1935}
1936EXPORT_SYMBOL_GPL(regulator_unregister);
1937
1938/**
1939 * regulator_suspend_prepare: prepare regulators for system wide suspend
1940 * @state: system suspend state
1941 *
1942 * Configure each regulator with it's suspend operating parameters for state.
1943 * This will usually be called by machine suspend code prior to supending.
1944 */
1945int regulator_suspend_prepare(suspend_state_t state)
1946{
1947	struct regulator_dev *rdev;
1948	int ret = 0;
1949
1950	/* ON is handled by regulator active state */
1951	if (state == PM_SUSPEND_ON)
1952		return -EINVAL;
1953
1954	mutex_lock(&regulator_list_mutex);
1955	list_for_each_entry(rdev, &regulator_list, list) {
1956
1957		mutex_lock(&rdev->mutex);
1958		ret = suspend_prepare(rdev, state);
1959		mutex_unlock(&rdev->mutex);
1960
1961		if (ret < 0) {
1962			printk(KERN_ERR "%s: failed to prepare %s\n",
1963				__func__, rdev->desc->name);
1964			goto out;
1965		}
1966	}
1967out:
1968	mutex_unlock(&regulator_list_mutex);
1969	return ret;
1970}
1971EXPORT_SYMBOL_GPL(regulator_suspend_prepare);
1972
1973/**
1974 * rdev_get_drvdata - get rdev regulator driver data
1975 * @rdev: regulator
1976 *
1977 * Get rdev regulator driver private data. This call can be used in the
1978 * regulator driver context.
1979 */
1980void *rdev_get_drvdata(struct regulator_dev *rdev)
1981{
1982	return rdev->reg_data;
1983}
1984EXPORT_SYMBOL_GPL(rdev_get_drvdata);
1985
1986/**
1987 * regulator_get_drvdata - get regulator driver data
1988 * @regulator: regulator
1989 *
1990 * Get regulator driver private data. This call can be used in the consumer
1991 * driver context when non API regulator specific functions need to be called.
1992 */
1993void *regulator_get_drvdata(struct regulator *regulator)
1994{
1995	return regulator->rdev->reg_data;
1996}
1997EXPORT_SYMBOL_GPL(regulator_get_drvdata);
1998
1999/**
2000 * regulator_set_drvdata - set regulator driver data
2001 * @regulator: regulator
2002 * @data: data
2003 */
2004void regulator_set_drvdata(struct regulator *regulator, void *data)
2005{
2006	regulator->rdev->reg_data = data;
2007}
2008EXPORT_SYMBOL_GPL(regulator_set_drvdata);
2009
2010/**
2011 * regulator_get_id - get regulator ID
2012 * @rdev: regulator
2013 */
2014int rdev_get_id(struct regulator_dev *rdev)
2015{
2016	return rdev->desc->id;
2017}
2018EXPORT_SYMBOL_GPL(rdev_get_id);
2019
2020struct device *rdev_get_dev(struct regulator_dev *rdev)
2021{
2022	return &rdev->dev;
2023}
2024EXPORT_SYMBOL_GPL(rdev_get_dev);
2025
2026void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
2027{
2028	return reg_init_data->driver_data;
2029}
2030EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
2031
2032static int __init regulator_init(void)
2033{
2034	printk(KERN_INFO "regulator: core version %s\n", REGULATOR_VERSION);
2035	return class_register(&regulator_class);
2036}
2037
2038/* init early to allow our consumers to complete system booting */
2039core_initcall(regulator_init);
2040