core.c revision 31aae2beeb3d601d556b6a8c39085940ad1e9f42
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/delay.h>
23#include <linux/regulator/consumer.h>
24#include <linux/regulator/driver.h>
25#include <linux/regulator/machine.h>
26
27#define REGULATOR_VERSION "0.5"
28
29static DEFINE_MUTEX(regulator_list_mutex);
30static LIST_HEAD(regulator_list);
31static LIST_HEAD(regulator_map_list);
32static int has_full_constraints;
33
34/*
35 * struct regulator_map
36 *
37 * Used to provide symbolic supply names to devices.
38 */
39struct regulator_map {
40	struct list_head list;
41	const char *dev_name;   /* The dev_name() for the consumer */
42	const char *supply;
43	struct regulator_dev *regulator;
44};
45
46/*
47 * struct regulator
48 *
49 * One for each consumer device.
50 */
51struct regulator {
52	struct device *dev;
53	struct list_head list;
54	int uA_load;
55	int min_uV;
56	int max_uV;
57	char *supply_name;
58	struct device_attribute dev_attr;
59	struct regulator_dev *rdev;
60};
61
62static int _regulator_is_enabled(struct regulator_dev *rdev);
63static int _regulator_disable(struct regulator_dev *rdev);
64static int _regulator_get_voltage(struct regulator_dev *rdev);
65static int _regulator_get_current_limit(struct regulator_dev *rdev);
66static unsigned int _regulator_get_mode(struct regulator_dev *rdev);
67static void _notifier_call_chain(struct regulator_dev *rdev,
68				  unsigned long event, void *data);
69
70static const char *rdev_get_name(struct regulator_dev *rdev)
71{
72	if (rdev->constraints && rdev->constraints->name)
73		return rdev->constraints->name;
74	else if (rdev->desc->name)
75		return rdev->desc->name;
76	else
77		return "";
78}
79
80/* gets the regulator for a given consumer device */
81static struct regulator *get_device_regulator(struct device *dev)
82{
83	struct regulator *regulator = NULL;
84	struct regulator_dev *rdev;
85
86	mutex_lock(&regulator_list_mutex);
87	list_for_each_entry(rdev, &regulator_list, list) {
88		mutex_lock(&rdev->mutex);
89		list_for_each_entry(regulator, &rdev->consumer_list, list) {
90			if (regulator->dev == dev) {
91				mutex_unlock(&rdev->mutex);
92				mutex_unlock(&regulator_list_mutex);
93				return regulator;
94			}
95		}
96		mutex_unlock(&rdev->mutex);
97	}
98	mutex_unlock(&regulator_list_mutex);
99	return NULL;
100}
101
102/* Platform voltage constraint check */
103static int regulator_check_voltage(struct regulator_dev *rdev,
104				   int *min_uV, int *max_uV)
105{
106	BUG_ON(*min_uV > *max_uV);
107
108	if (!rdev->constraints) {
109		printk(KERN_ERR "%s: no constraints for %s\n", __func__,
110		       rdev_get_name(rdev));
111		return -ENODEV;
112	}
113	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
114		printk(KERN_ERR "%s: operation not allowed for %s\n",
115		       __func__, rdev_get_name(rdev));
116		return -EPERM;
117	}
118
119	if (*max_uV > rdev->constraints->max_uV)
120		*max_uV = rdev->constraints->max_uV;
121	if (*min_uV < rdev->constraints->min_uV)
122		*min_uV = rdev->constraints->min_uV;
123
124	if (*min_uV > *max_uV)
125		return -EINVAL;
126
127	return 0;
128}
129
130/* current constraint check */
131static int regulator_check_current_limit(struct regulator_dev *rdev,
132					int *min_uA, int *max_uA)
133{
134	BUG_ON(*min_uA > *max_uA);
135
136	if (!rdev->constraints) {
137		printk(KERN_ERR "%s: no constraints for %s\n", __func__,
138		       rdev_get_name(rdev));
139		return -ENODEV;
140	}
141	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_CURRENT)) {
142		printk(KERN_ERR "%s: operation not allowed for %s\n",
143		       __func__, rdev_get_name(rdev));
144		return -EPERM;
145	}
146
147	if (*max_uA > rdev->constraints->max_uA)
148		*max_uA = rdev->constraints->max_uA;
149	if (*min_uA < rdev->constraints->min_uA)
150		*min_uA = rdev->constraints->min_uA;
151
152	if (*min_uA > *max_uA)
153		return -EINVAL;
154
155	return 0;
156}
157
158/* operating mode constraint check */
159static int regulator_check_mode(struct regulator_dev *rdev, int mode)
160{
161	switch (mode) {
162	case REGULATOR_MODE_FAST:
163	case REGULATOR_MODE_NORMAL:
164	case REGULATOR_MODE_IDLE:
165	case REGULATOR_MODE_STANDBY:
166		break;
167	default:
168		return -EINVAL;
169	}
170
171	if (!rdev->constraints) {
172		printk(KERN_ERR "%s: no constraints for %s\n", __func__,
173		       rdev_get_name(rdev));
174		return -ENODEV;
175	}
176	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_MODE)) {
177		printk(KERN_ERR "%s: operation not allowed for %s\n",
178		       __func__, rdev_get_name(rdev));
179		return -EPERM;
180	}
181	if (!(rdev->constraints->valid_modes_mask & mode)) {
182		printk(KERN_ERR "%s: invalid mode %x for %s\n",
183		       __func__, mode, rdev_get_name(rdev));
184		return -EINVAL;
185	}
186	return 0;
187}
188
189/* dynamic regulator mode switching constraint check */
190static int regulator_check_drms(struct regulator_dev *rdev)
191{
192	if (!rdev->constraints) {
193		printk(KERN_ERR "%s: no constraints for %s\n", __func__,
194		       rdev_get_name(rdev));
195		return -ENODEV;
196	}
197	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS)) {
198		printk(KERN_ERR "%s: operation not allowed for %s\n",
199		       __func__, rdev_get_name(rdev));
200		return -EPERM;
201	}
202	return 0;
203}
204
205static ssize_t device_requested_uA_show(struct device *dev,
206			     struct device_attribute *attr, char *buf)
207{
208	struct regulator *regulator;
209
210	regulator = get_device_regulator(dev);
211	if (regulator == NULL)
212		return 0;
213
214	return sprintf(buf, "%d\n", regulator->uA_load);
215}
216
217static ssize_t regulator_uV_show(struct device *dev,
218				struct device_attribute *attr, char *buf)
219{
220	struct regulator_dev *rdev = dev_get_drvdata(dev);
221	ssize_t ret;
222
223	mutex_lock(&rdev->mutex);
224	ret = sprintf(buf, "%d\n", _regulator_get_voltage(rdev));
225	mutex_unlock(&rdev->mutex);
226
227	return ret;
228}
229static DEVICE_ATTR(microvolts, 0444, regulator_uV_show, NULL);
230
231static ssize_t regulator_uA_show(struct device *dev,
232				struct device_attribute *attr, char *buf)
233{
234	struct regulator_dev *rdev = dev_get_drvdata(dev);
235
236	return sprintf(buf, "%d\n", _regulator_get_current_limit(rdev));
237}
238static DEVICE_ATTR(microamps, 0444, regulator_uA_show, NULL);
239
240static ssize_t regulator_name_show(struct device *dev,
241			     struct device_attribute *attr, char *buf)
242{
243	struct regulator_dev *rdev = dev_get_drvdata(dev);
244
245	return sprintf(buf, "%s\n", rdev_get_name(rdev));
246}
247
248static ssize_t regulator_print_opmode(char *buf, int mode)
249{
250	switch (mode) {
251	case REGULATOR_MODE_FAST:
252		return sprintf(buf, "fast\n");
253	case REGULATOR_MODE_NORMAL:
254		return sprintf(buf, "normal\n");
255	case REGULATOR_MODE_IDLE:
256		return sprintf(buf, "idle\n");
257	case REGULATOR_MODE_STANDBY:
258		return sprintf(buf, "standby\n");
259	}
260	return sprintf(buf, "unknown\n");
261}
262
263static ssize_t regulator_opmode_show(struct device *dev,
264				    struct device_attribute *attr, char *buf)
265{
266	struct regulator_dev *rdev = dev_get_drvdata(dev);
267
268	return regulator_print_opmode(buf, _regulator_get_mode(rdev));
269}
270static DEVICE_ATTR(opmode, 0444, regulator_opmode_show, NULL);
271
272static ssize_t regulator_print_state(char *buf, int state)
273{
274	if (state > 0)
275		return sprintf(buf, "enabled\n");
276	else if (state == 0)
277		return sprintf(buf, "disabled\n");
278	else
279		return sprintf(buf, "unknown\n");
280}
281
282static ssize_t regulator_state_show(struct device *dev,
283				   struct device_attribute *attr, char *buf)
284{
285	struct regulator_dev *rdev = dev_get_drvdata(dev);
286	ssize_t ret;
287
288	mutex_lock(&rdev->mutex);
289	ret = regulator_print_state(buf, _regulator_is_enabled(rdev));
290	mutex_unlock(&rdev->mutex);
291
292	return ret;
293}
294static DEVICE_ATTR(state, 0444, regulator_state_show, NULL);
295
296static ssize_t regulator_status_show(struct device *dev,
297				   struct device_attribute *attr, char *buf)
298{
299	struct regulator_dev *rdev = dev_get_drvdata(dev);
300	int status;
301	char *label;
302
303	status = rdev->desc->ops->get_status(rdev);
304	if (status < 0)
305		return status;
306
307	switch (status) {
308	case REGULATOR_STATUS_OFF:
309		label = "off";
310		break;
311	case REGULATOR_STATUS_ON:
312		label = "on";
313		break;
314	case REGULATOR_STATUS_ERROR:
315		label = "error";
316		break;
317	case REGULATOR_STATUS_FAST:
318		label = "fast";
319		break;
320	case REGULATOR_STATUS_NORMAL:
321		label = "normal";
322		break;
323	case REGULATOR_STATUS_IDLE:
324		label = "idle";
325		break;
326	case REGULATOR_STATUS_STANDBY:
327		label = "standby";
328		break;
329	default:
330		return -ERANGE;
331	}
332
333	return sprintf(buf, "%s\n", label);
334}
335static DEVICE_ATTR(status, 0444, regulator_status_show, NULL);
336
337static ssize_t regulator_min_uA_show(struct device *dev,
338				    struct device_attribute *attr, char *buf)
339{
340	struct regulator_dev *rdev = dev_get_drvdata(dev);
341
342	if (!rdev->constraints)
343		return sprintf(buf, "constraint not defined\n");
344
345	return sprintf(buf, "%d\n", rdev->constraints->min_uA);
346}
347static DEVICE_ATTR(min_microamps, 0444, regulator_min_uA_show, NULL);
348
349static ssize_t regulator_max_uA_show(struct device *dev,
350				    struct device_attribute *attr, char *buf)
351{
352	struct regulator_dev *rdev = dev_get_drvdata(dev);
353
354	if (!rdev->constraints)
355		return sprintf(buf, "constraint not defined\n");
356
357	return sprintf(buf, "%d\n", rdev->constraints->max_uA);
358}
359static DEVICE_ATTR(max_microamps, 0444, regulator_max_uA_show, NULL);
360
361static ssize_t regulator_min_uV_show(struct device *dev,
362				    struct device_attribute *attr, char *buf)
363{
364	struct regulator_dev *rdev = dev_get_drvdata(dev);
365
366	if (!rdev->constraints)
367		return sprintf(buf, "constraint not defined\n");
368
369	return sprintf(buf, "%d\n", rdev->constraints->min_uV);
370}
371static DEVICE_ATTR(min_microvolts, 0444, regulator_min_uV_show, NULL);
372
373static ssize_t regulator_max_uV_show(struct device *dev,
374				    struct device_attribute *attr, char *buf)
375{
376	struct regulator_dev *rdev = dev_get_drvdata(dev);
377
378	if (!rdev->constraints)
379		return sprintf(buf, "constraint not defined\n");
380
381	return sprintf(buf, "%d\n", rdev->constraints->max_uV);
382}
383static DEVICE_ATTR(max_microvolts, 0444, regulator_max_uV_show, NULL);
384
385static ssize_t regulator_total_uA_show(struct device *dev,
386				      struct device_attribute *attr, char *buf)
387{
388	struct regulator_dev *rdev = dev_get_drvdata(dev);
389	struct regulator *regulator;
390	int uA = 0;
391
392	mutex_lock(&rdev->mutex);
393	list_for_each_entry(regulator, &rdev->consumer_list, list)
394		uA += regulator->uA_load;
395	mutex_unlock(&rdev->mutex);
396	return sprintf(buf, "%d\n", uA);
397}
398static DEVICE_ATTR(requested_microamps, 0444, regulator_total_uA_show, NULL);
399
400static ssize_t regulator_num_users_show(struct device *dev,
401				      struct device_attribute *attr, char *buf)
402{
403	struct regulator_dev *rdev = dev_get_drvdata(dev);
404	return sprintf(buf, "%d\n", rdev->use_count);
405}
406
407static ssize_t regulator_type_show(struct device *dev,
408				  struct device_attribute *attr, char *buf)
409{
410	struct regulator_dev *rdev = dev_get_drvdata(dev);
411
412	switch (rdev->desc->type) {
413	case REGULATOR_VOLTAGE:
414		return sprintf(buf, "voltage\n");
415	case REGULATOR_CURRENT:
416		return sprintf(buf, "current\n");
417	}
418	return sprintf(buf, "unknown\n");
419}
420
421static ssize_t regulator_suspend_mem_uV_show(struct device *dev,
422				struct device_attribute *attr, char *buf)
423{
424	struct regulator_dev *rdev = dev_get_drvdata(dev);
425
426	return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
427}
428static DEVICE_ATTR(suspend_mem_microvolts, 0444,
429		regulator_suspend_mem_uV_show, NULL);
430
431static ssize_t regulator_suspend_disk_uV_show(struct device *dev,
432				struct device_attribute *attr, char *buf)
433{
434	struct regulator_dev *rdev = dev_get_drvdata(dev);
435
436	return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
437}
438static DEVICE_ATTR(suspend_disk_microvolts, 0444,
439		regulator_suspend_disk_uV_show, NULL);
440
441static ssize_t regulator_suspend_standby_uV_show(struct device *dev,
442				struct device_attribute *attr, char *buf)
443{
444	struct regulator_dev *rdev = dev_get_drvdata(dev);
445
446	return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
447}
448static DEVICE_ATTR(suspend_standby_microvolts, 0444,
449		regulator_suspend_standby_uV_show, NULL);
450
451static ssize_t regulator_suspend_mem_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_mem.mode);
458}
459static DEVICE_ATTR(suspend_mem_mode, 0444,
460		regulator_suspend_mem_mode_show, NULL);
461
462static ssize_t regulator_suspend_disk_mode_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_opmode(buf,
468		rdev->constraints->state_disk.mode);
469}
470static DEVICE_ATTR(suspend_disk_mode, 0444,
471		regulator_suspend_disk_mode_show, NULL);
472
473static ssize_t regulator_suspend_standby_mode_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_opmode(buf,
479		rdev->constraints->state_standby.mode);
480}
481static DEVICE_ATTR(suspend_standby_mode, 0444,
482		regulator_suspend_standby_mode_show, NULL);
483
484static ssize_t regulator_suspend_mem_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_mem.enabled);
491}
492static DEVICE_ATTR(suspend_mem_state, 0444,
493		regulator_suspend_mem_state_show, NULL);
494
495static ssize_t regulator_suspend_disk_state_show(struct device *dev,
496				   struct device_attribute *attr, char *buf)
497{
498	struct regulator_dev *rdev = dev_get_drvdata(dev);
499
500	return regulator_print_state(buf,
501			rdev->constraints->state_disk.enabled);
502}
503static DEVICE_ATTR(suspend_disk_state, 0444,
504		regulator_suspend_disk_state_show, NULL);
505
506static ssize_t regulator_suspend_standby_state_show(struct device *dev,
507				   struct device_attribute *attr, char *buf)
508{
509	struct regulator_dev *rdev = dev_get_drvdata(dev);
510
511	return regulator_print_state(buf,
512			rdev->constraints->state_standby.enabled);
513}
514static DEVICE_ATTR(suspend_standby_state, 0444,
515		regulator_suspend_standby_state_show, NULL);
516
517
518/*
519 * These are the only attributes are present for all regulators.
520 * Other attributes are a function of regulator functionality.
521 */
522static struct device_attribute regulator_dev_attrs[] = {
523	__ATTR(name, 0444, regulator_name_show, NULL),
524	__ATTR(num_users, 0444, regulator_num_users_show, NULL),
525	__ATTR(type, 0444, regulator_type_show, NULL),
526	__ATTR_NULL,
527};
528
529static void regulator_dev_release(struct device *dev)
530{
531	struct regulator_dev *rdev = dev_get_drvdata(dev);
532	kfree(rdev);
533}
534
535static struct class regulator_class = {
536	.name = "regulator",
537	.dev_release = regulator_dev_release,
538	.dev_attrs = regulator_dev_attrs,
539};
540
541/* Calculate the new optimum regulator operating mode based on the new total
542 * consumer load. All locks held by caller */
543static void drms_uA_update(struct regulator_dev *rdev)
544{
545	struct regulator *sibling;
546	int current_uA = 0, output_uV, input_uV, err;
547	unsigned int mode;
548
549	err = regulator_check_drms(rdev);
550	if (err < 0 || !rdev->desc->ops->get_optimum_mode ||
551	    !rdev->desc->ops->get_voltage || !rdev->desc->ops->set_mode)
552		return;
553
554	/* get output voltage */
555	output_uV = rdev->desc->ops->get_voltage(rdev);
556	if (output_uV <= 0)
557		return;
558
559	/* get input voltage */
560	if (rdev->supply && rdev->supply->desc->ops->get_voltage)
561		input_uV = rdev->supply->desc->ops->get_voltage(rdev->supply);
562	else
563		input_uV = rdev->constraints->input_uV;
564	if (input_uV <= 0)
565		return;
566
567	/* calc total requested load */
568	list_for_each_entry(sibling, &rdev->consumer_list, list)
569		current_uA += sibling->uA_load;
570
571	/* now get the optimum mode for our new total regulator load */
572	mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
573						  output_uV, current_uA);
574
575	/* check the new mode is allowed */
576	err = regulator_check_mode(rdev, mode);
577	if (err == 0)
578		rdev->desc->ops->set_mode(rdev, mode);
579}
580
581static int suspend_set_state(struct regulator_dev *rdev,
582	struct regulator_state *rstate)
583{
584	int ret = 0;
585	bool can_set_state;
586
587	can_set_state = rdev->desc->ops->set_suspend_enable &&
588		rdev->desc->ops->set_suspend_disable;
589
590	/* If we have no suspend mode configration don't set anything;
591	 * only warn if the driver actually makes the suspend mode
592	 * configurable.
593	 */
594	if (!rstate->enabled && !rstate->disabled) {
595		if (can_set_state)
596			printk(KERN_WARNING "%s: No configuration for %s\n",
597			       __func__, rdev_get_name(rdev));
598		return 0;
599	}
600
601	if (rstate->enabled && rstate->disabled) {
602		printk(KERN_ERR "%s: invalid configuration for %s\n",
603		       __func__, rdev_get_name(rdev));
604		return -EINVAL;
605	}
606
607	if (!can_set_state) {
608		printk(KERN_ERR "%s: no way to set suspend state\n",
609			__func__);
610		return -EINVAL;
611	}
612
613	if (rstate->enabled)
614		ret = rdev->desc->ops->set_suspend_enable(rdev);
615	else
616		ret = rdev->desc->ops->set_suspend_disable(rdev);
617	if (ret < 0) {
618		printk(KERN_ERR "%s: failed to enabled/disable\n", __func__);
619		return ret;
620	}
621
622	if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
623		ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
624		if (ret < 0) {
625			printk(KERN_ERR "%s: failed to set voltage\n",
626				__func__);
627			return ret;
628		}
629	}
630
631	if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
632		ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
633		if (ret < 0) {
634			printk(KERN_ERR "%s: failed to set mode\n", __func__);
635			return ret;
636		}
637	}
638	return ret;
639}
640
641/* locks held by caller */
642static int suspend_prepare(struct regulator_dev *rdev, suspend_state_t state)
643{
644	if (!rdev->constraints)
645		return -EINVAL;
646
647	switch (state) {
648	case PM_SUSPEND_STANDBY:
649		return suspend_set_state(rdev,
650			&rdev->constraints->state_standby);
651	case PM_SUSPEND_MEM:
652		return suspend_set_state(rdev,
653			&rdev->constraints->state_mem);
654	case PM_SUSPEND_MAX:
655		return suspend_set_state(rdev,
656			&rdev->constraints->state_disk);
657	default:
658		return -EINVAL;
659	}
660}
661
662static void print_constraints(struct regulator_dev *rdev)
663{
664	struct regulation_constraints *constraints = rdev->constraints;
665	char buf[80] = "";
666	int count = 0;
667	int ret;
668
669	if (constraints->min_uV && constraints->max_uV) {
670		if (constraints->min_uV == constraints->max_uV)
671			count += sprintf(buf + count, "%d mV ",
672					 constraints->min_uV / 1000);
673		else
674			count += sprintf(buf + count, "%d <--> %d mV ",
675					 constraints->min_uV / 1000,
676					 constraints->max_uV / 1000);
677	}
678
679	if (!constraints->min_uV ||
680	    constraints->min_uV != constraints->max_uV) {
681		ret = _regulator_get_voltage(rdev);
682		if (ret > 0)
683			count += sprintf(buf + count, "at %d mV ", ret / 1000);
684	}
685
686	if (constraints->min_uA && constraints->max_uA) {
687		if (constraints->min_uA == constraints->max_uA)
688			count += sprintf(buf + count, "%d mA ",
689					 constraints->min_uA / 1000);
690		else
691			count += sprintf(buf + count, "%d <--> %d mA ",
692					 constraints->min_uA / 1000,
693					 constraints->max_uA / 1000);
694	}
695
696	if (!constraints->min_uA ||
697	    constraints->min_uA != constraints->max_uA) {
698		ret = _regulator_get_current_limit(rdev);
699		if (ret > 0)
700			count += sprintf(buf + count, "at %d uA ", ret / 1000);
701	}
702
703	if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
704		count += sprintf(buf + count, "fast ");
705	if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
706		count += sprintf(buf + count, "normal ");
707	if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
708		count += sprintf(buf + count, "idle ");
709	if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
710		count += sprintf(buf + count, "standby");
711
712	printk(KERN_INFO "regulator: %s: %s\n", rdev_get_name(rdev), buf);
713}
714
715static int machine_constraints_voltage(struct regulator_dev *rdev,
716	struct regulation_constraints *constraints)
717{
718	struct regulator_ops *ops = rdev->desc->ops;
719	const char *name = rdev_get_name(rdev);
720	int ret;
721
722	/* do we need to apply the constraint voltage */
723	if (rdev->constraints->apply_uV &&
724		rdev->constraints->min_uV == rdev->constraints->max_uV &&
725		ops->set_voltage) {
726		ret = ops->set_voltage(rdev,
727			rdev->constraints->min_uV, rdev->constraints->max_uV);
728			if (ret < 0) {
729				printk(KERN_ERR "%s: failed to apply %duV constraint to %s\n",
730				       __func__,
731				       rdev->constraints->min_uV, name);
732				rdev->constraints = NULL;
733				return ret;
734			}
735	}
736
737	/* constrain machine-level voltage specs to fit
738	 * the actual range supported by this regulator.
739	 */
740	if (ops->list_voltage && rdev->desc->n_voltages) {
741		int	count = rdev->desc->n_voltages;
742		int	i;
743		int	min_uV = INT_MAX;
744		int	max_uV = INT_MIN;
745		int	cmin = constraints->min_uV;
746		int	cmax = constraints->max_uV;
747
748		/* it's safe to autoconfigure fixed-voltage supplies
749		   and the constraints are used by list_voltage. */
750		if (count == 1 && !cmin) {
751			cmin = 1;
752			cmax = INT_MAX;
753			constraints->min_uV = cmin;
754			constraints->max_uV = cmax;
755		}
756
757		/* voltage constraints are optional */
758		if ((cmin == 0) && (cmax == 0))
759			return 0;
760
761		/* else require explicit machine-level constraints */
762		if (cmin <= 0 || cmax <= 0 || cmax < cmin) {
763			pr_err("%s: %s '%s' voltage constraints\n",
764				       __func__, "invalid", name);
765			return -EINVAL;
766		}
767
768		/* initial: [cmin..cmax] valid, [min_uV..max_uV] not */
769		for (i = 0; i < count; i++) {
770			int	value;
771
772			value = ops->list_voltage(rdev, i);
773			if (value <= 0)
774				continue;
775
776			/* maybe adjust [min_uV..max_uV] */
777			if (value >= cmin && value < min_uV)
778				min_uV = value;
779			if (value <= cmax && value > max_uV)
780				max_uV = value;
781		}
782
783		/* final: [min_uV..max_uV] valid iff constraints valid */
784		if (max_uV < min_uV) {
785			pr_err("%s: %s '%s' voltage constraints\n",
786				       __func__, "unsupportable", name);
787			return -EINVAL;
788		}
789
790		/* use regulator's subset of machine constraints */
791		if (constraints->min_uV < min_uV) {
792			pr_debug("%s: override '%s' %s, %d -> %d\n",
793				       __func__, name, "min_uV",
794					constraints->min_uV, min_uV);
795			constraints->min_uV = min_uV;
796		}
797		if (constraints->max_uV > max_uV) {
798			pr_debug("%s: override '%s' %s, %d -> %d\n",
799				       __func__, name, "max_uV",
800					constraints->max_uV, max_uV);
801			constraints->max_uV = max_uV;
802		}
803	}
804
805	return 0;
806}
807
808/**
809 * set_machine_constraints - sets regulator constraints
810 * @rdev: regulator source
811 * @constraints: constraints to apply
812 *
813 * Allows platform initialisation code to define and constrain
814 * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
815 * Constraints *must* be set by platform code in order for some
816 * regulator operations to proceed i.e. set_voltage, set_current_limit,
817 * set_mode.
818 */
819static int set_machine_constraints(struct regulator_dev *rdev,
820	struct regulation_constraints *constraints)
821{
822	int ret = 0;
823	const char *name;
824	struct regulator_ops *ops = rdev->desc->ops;
825
826	rdev->constraints = constraints;
827
828	name = rdev_get_name(rdev);
829
830	ret = machine_constraints_voltage(rdev, constraints);
831	if (ret != 0)
832		goto out;
833
834	/* do we need to setup our suspend state */
835	if (constraints->initial_state) {
836		ret = suspend_prepare(rdev, constraints->initial_state);
837		if (ret < 0) {
838			printk(KERN_ERR "%s: failed to set suspend state for %s\n",
839			       __func__, name);
840			rdev->constraints = NULL;
841			goto out;
842		}
843	}
844
845	if (constraints->initial_mode) {
846		if (!ops->set_mode) {
847			printk(KERN_ERR "%s: no set_mode operation for %s\n",
848			       __func__, name);
849			ret = -EINVAL;
850			goto out;
851		}
852
853		ret = ops->set_mode(rdev, constraints->initial_mode);
854		if (ret < 0) {
855			printk(KERN_ERR
856			       "%s: failed to set initial mode for %s: %d\n",
857			       __func__, name, ret);
858			goto out;
859		}
860	}
861
862	/* If the constraints say the regulator should be on at this point
863	 * and we have control then make sure it is enabled.
864	 */
865	if ((constraints->always_on || constraints->boot_on) && ops->enable) {
866		ret = ops->enable(rdev);
867		if (ret < 0) {
868			printk(KERN_ERR "%s: failed to enable %s\n",
869			       __func__, name);
870			rdev->constraints = NULL;
871			goto out;
872		}
873	}
874
875	print_constraints(rdev);
876out:
877	return ret;
878}
879
880/**
881 * set_supply - set regulator supply regulator
882 * @rdev: regulator name
883 * @supply_rdev: supply regulator name
884 *
885 * Called by platform initialisation code to set the supply regulator for this
886 * regulator. This ensures that a regulators supply will also be enabled by the
887 * core if it's child is enabled.
888 */
889static int set_supply(struct regulator_dev *rdev,
890	struct regulator_dev *supply_rdev)
891{
892	int err;
893
894	err = sysfs_create_link(&rdev->dev.kobj, &supply_rdev->dev.kobj,
895				"supply");
896	if (err) {
897		printk(KERN_ERR
898		       "%s: could not add device link %s err %d\n",
899		       __func__, supply_rdev->dev.kobj.name, err);
900		       goto out;
901	}
902	rdev->supply = supply_rdev;
903	list_add(&rdev->slist, &supply_rdev->supply_list);
904out:
905	return err;
906}
907
908/**
909 * set_consumer_device_supply: Bind a regulator to a symbolic supply
910 * @rdev:         regulator source
911 * @consumer_dev: device the supply applies to
912 * @consumer_dev_name: dev_name() string for device supply applies to
913 * @supply:       symbolic name for supply
914 *
915 * Allows platform initialisation code to map physical regulator
916 * sources to symbolic names for supplies for use by devices.  Devices
917 * should use these symbolic names to request regulators, avoiding the
918 * need to provide board-specific regulator names as platform data.
919 *
920 * Only one of consumer_dev and consumer_dev_name may be specified.
921 */
922static int set_consumer_device_supply(struct regulator_dev *rdev,
923	struct device *consumer_dev, const char *consumer_dev_name,
924	const char *supply)
925{
926	struct regulator_map *node;
927	int has_dev;
928
929	if (consumer_dev && consumer_dev_name)
930		return -EINVAL;
931
932	if (!consumer_dev_name && consumer_dev)
933		consumer_dev_name = dev_name(consumer_dev);
934
935	if (supply == NULL)
936		return -EINVAL;
937
938	if (consumer_dev_name != NULL)
939		has_dev = 1;
940	else
941		has_dev = 0;
942
943	list_for_each_entry(node, &regulator_map_list, list) {
944		if (consumer_dev_name != node->dev_name)
945			continue;
946		if (strcmp(node->supply, supply) != 0)
947			continue;
948
949		dev_dbg(consumer_dev, "%s/%s is '%s' supply; fail %s/%s\n",
950				dev_name(&node->regulator->dev),
951				node->regulator->desc->name,
952				supply,
953				dev_name(&rdev->dev), rdev_get_name(rdev));
954		return -EBUSY;
955	}
956
957	node = kzalloc(sizeof(struct regulator_map), GFP_KERNEL);
958	if (node == NULL)
959		return -ENOMEM;
960
961	node->regulator = rdev;
962	node->supply = supply;
963
964	if (has_dev) {
965		node->dev_name = kstrdup(consumer_dev_name, GFP_KERNEL);
966		if (node->dev_name == NULL) {
967			kfree(node);
968			return -ENOMEM;
969		}
970	}
971
972	list_add(&node->list, &regulator_map_list);
973	return 0;
974}
975
976static void unset_consumer_device_supply(struct regulator_dev *rdev,
977	const char *consumer_dev_name, struct device *consumer_dev)
978{
979	struct regulator_map *node, *n;
980
981	if (consumer_dev && !consumer_dev_name)
982		consumer_dev_name = dev_name(consumer_dev);
983
984	list_for_each_entry_safe(node, n, &regulator_map_list, list) {
985		if (rdev != node->regulator)
986			continue;
987
988		if (consumer_dev_name && node->dev_name &&
989		    strcmp(consumer_dev_name, node->dev_name))
990			continue;
991
992		list_del(&node->list);
993		kfree(node->dev_name);
994		kfree(node);
995		return;
996	}
997}
998
999static void unset_regulator_supplies(struct regulator_dev *rdev)
1000{
1001	struct regulator_map *node, *n;
1002
1003	list_for_each_entry_safe(node, n, &regulator_map_list, list) {
1004		if (rdev == node->regulator) {
1005			list_del(&node->list);
1006			kfree(node->dev_name);
1007			kfree(node);
1008			return;
1009		}
1010	}
1011}
1012
1013#define REG_STR_SIZE	32
1014
1015static struct regulator *create_regulator(struct regulator_dev *rdev,
1016					  struct device *dev,
1017					  const char *supply_name)
1018{
1019	struct regulator *regulator;
1020	char buf[REG_STR_SIZE];
1021	int err, size;
1022
1023	regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
1024	if (regulator == NULL)
1025		return NULL;
1026
1027	mutex_lock(&rdev->mutex);
1028	regulator->rdev = rdev;
1029	list_add(&regulator->list, &rdev->consumer_list);
1030
1031	if (dev) {
1032		/* create a 'requested_microamps_name' sysfs entry */
1033		size = scnprintf(buf, REG_STR_SIZE, "microamps_requested_%s",
1034			supply_name);
1035		if (size >= REG_STR_SIZE)
1036			goto overflow_err;
1037
1038		regulator->dev = dev;
1039		regulator->dev_attr.attr.name = kstrdup(buf, GFP_KERNEL);
1040		if (regulator->dev_attr.attr.name == NULL)
1041			goto attr_name_err;
1042
1043		regulator->dev_attr.attr.owner = THIS_MODULE;
1044		regulator->dev_attr.attr.mode = 0444;
1045		regulator->dev_attr.show = device_requested_uA_show;
1046		err = device_create_file(dev, &regulator->dev_attr);
1047		if (err < 0) {
1048			printk(KERN_WARNING "%s: could not add regulator_dev"
1049				" load sysfs\n", __func__);
1050			goto attr_name_err;
1051		}
1052
1053		/* also add a link to the device sysfs entry */
1054		size = scnprintf(buf, REG_STR_SIZE, "%s-%s",
1055				 dev->kobj.name, supply_name);
1056		if (size >= REG_STR_SIZE)
1057			goto attr_err;
1058
1059		regulator->supply_name = kstrdup(buf, GFP_KERNEL);
1060		if (regulator->supply_name == NULL)
1061			goto attr_err;
1062
1063		err = sysfs_create_link(&rdev->dev.kobj, &dev->kobj,
1064					buf);
1065		if (err) {
1066			printk(KERN_WARNING
1067			       "%s: could not add device link %s err %d\n",
1068			       __func__, dev->kobj.name, err);
1069			device_remove_file(dev, &regulator->dev_attr);
1070			goto link_name_err;
1071		}
1072	}
1073	mutex_unlock(&rdev->mutex);
1074	return regulator;
1075link_name_err:
1076	kfree(regulator->supply_name);
1077attr_err:
1078	device_remove_file(regulator->dev, &regulator->dev_attr);
1079attr_name_err:
1080	kfree(regulator->dev_attr.attr.name);
1081overflow_err:
1082	list_del(&regulator->list);
1083	kfree(regulator);
1084	mutex_unlock(&rdev->mutex);
1085	return NULL;
1086}
1087
1088static int _regulator_get_enable_time(struct regulator_dev *rdev)
1089{
1090	if (!rdev->desc->ops->enable_time)
1091		return 0;
1092	return rdev->desc->ops->enable_time(rdev);
1093}
1094
1095/* Internal regulator request function */
1096static struct regulator *_regulator_get(struct device *dev, const char *id,
1097					int exclusive)
1098{
1099	struct regulator_dev *rdev;
1100	struct regulator_map *map;
1101	struct regulator *regulator = ERR_PTR(-ENODEV);
1102	const char *devname = NULL;
1103	int ret;
1104
1105	if (id == NULL) {
1106		printk(KERN_ERR "regulator: get() with no identifier\n");
1107		return regulator;
1108	}
1109
1110	if (dev)
1111		devname = dev_name(dev);
1112
1113	mutex_lock(&regulator_list_mutex);
1114
1115	list_for_each_entry(map, &regulator_map_list, list) {
1116		/* If the mapping has a device set up it must match */
1117		if (map->dev_name &&
1118		    (!devname || strcmp(map->dev_name, devname)))
1119			continue;
1120
1121		if (strcmp(map->supply, id) == 0) {
1122			rdev = map->regulator;
1123			goto found;
1124		}
1125	}
1126	mutex_unlock(&regulator_list_mutex);
1127	return regulator;
1128
1129found:
1130	if (rdev->exclusive) {
1131		regulator = ERR_PTR(-EPERM);
1132		goto out;
1133	}
1134
1135	if (exclusive && rdev->open_count) {
1136		regulator = ERR_PTR(-EBUSY);
1137		goto out;
1138	}
1139
1140	if (!try_module_get(rdev->owner))
1141		goto out;
1142
1143	regulator = create_regulator(rdev, dev, id);
1144	if (regulator == NULL) {
1145		regulator = ERR_PTR(-ENOMEM);
1146		module_put(rdev->owner);
1147	}
1148
1149	rdev->open_count++;
1150	if (exclusive) {
1151		rdev->exclusive = 1;
1152
1153		ret = _regulator_is_enabled(rdev);
1154		if (ret > 0)
1155			rdev->use_count = 1;
1156		else
1157			rdev->use_count = 0;
1158	}
1159
1160out:
1161	mutex_unlock(&regulator_list_mutex);
1162
1163	return regulator;
1164}
1165
1166/**
1167 * regulator_get - lookup and obtain a reference to a regulator.
1168 * @dev: device for regulator "consumer"
1169 * @id: Supply name or regulator ID.
1170 *
1171 * Returns a struct regulator corresponding to the regulator producer,
1172 * or IS_ERR() condition containing errno.
1173 *
1174 * Use of supply names configured via regulator_set_device_supply() is
1175 * strongly encouraged.  It is recommended that the supply name used
1176 * should match the name used for the supply and/or the relevant
1177 * device pins in the datasheet.
1178 */
1179struct regulator *regulator_get(struct device *dev, const char *id)
1180{
1181	return _regulator_get(dev, id, 0);
1182}
1183EXPORT_SYMBOL_GPL(regulator_get);
1184
1185/**
1186 * regulator_get_exclusive - obtain exclusive access to a regulator.
1187 * @dev: device for regulator "consumer"
1188 * @id: Supply name or regulator ID.
1189 *
1190 * Returns a struct regulator corresponding to the regulator producer,
1191 * or IS_ERR() condition containing errno.  Other consumers will be
1192 * unable to obtain this reference is held and the use count for the
1193 * regulator will be initialised to reflect the current state of the
1194 * regulator.
1195 *
1196 * This is intended for use by consumers which cannot tolerate shared
1197 * use of the regulator such as those which need to force the
1198 * regulator off for correct operation of the hardware they are
1199 * controlling.
1200 *
1201 * Use of supply names configured via regulator_set_device_supply() is
1202 * strongly encouraged.  It is recommended that the supply name used
1203 * should match the name used for the supply and/or the relevant
1204 * device pins in the datasheet.
1205 */
1206struct regulator *regulator_get_exclusive(struct device *dev, const char *id)
1207{
1208	return _regulator_get(dev, id, 1);
1209}
1210EXPORT_SYMBOL_GPL(regulator_get_exclusive);
1211
1212/**
1213 * regulator_put - "free" the regulator source
1214 * @regulator: regulator source
1215 *
1216 * Note: drivers must ensure that all regulator_enable calls made on this
1217 * regulator source are balanced by regulator_disable calls prior to calling
1218 * this function.
1219 */
1220void regulator_put(struct regulator *regulator)
1221{
1222	struct regulator_dev *rdev;
1223
1224	if (regulator == NULL || IS_ERR(regulator))
1225		return;
1226
1227	mutex_lock(&regulator_list_mutex);
1228	rdev = regulator->rdev;
1229
1230	/* remove any sysfs entries */
1231	if (regulator->dev) {
1232		sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
1233		kfree(regulator->supply_name);
1234		device_remove_file(regulator->dev, &regulator->dev_attr);
1235		kfree(regulator->dev_attr.attr.name);
1236	}
1237	list_del(&regulator->list);
1238	kfree(regulator);
1239
1240	rdev->open_count--;
1241	rdev->exclusive = 0;
1242
1243	module_put(rdev->owner);
1244	mutex_unlock(&regulator_list_mutex);
1245}
1246EXPORT_SYMBOL_GPL(regulator_put);
1247
1248static int _regulator_can_change_status(struct regulator_dev *rdev)
1249{
1250	if (!rdev->constraints)
1251		return 0;
1252
1253	if (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_STATUS)
1254		return 1;
1255	else
1256		return 0;
1257}
1258
1259/* locks held by regulator_enable() */
1260static int _regulator_enable(struct regulator_dev *rdev)
1261{
1262	int ret, delay;
1263
1264	/* do we need to enable the supply regulator first */
1265	if (rdev->supply) {
1266		ret = _regulator_enable(rdev->supply);
1267		if (ret < 0) {
1268			printk(KERN_ERR "%s: failed to enable %s: %d\n",
1269			       __func__, rdev_get_name(rdev), ret);
1270			return ret;
1271		}
1272	}
1273
1274	/* check voltage and requested load before enabling */
1275	if (rdev->constraints &&
1276	    (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS))
1277		drms_uA_update(rdev);
1278
1279	if (rdev->use_count == 0) {
1280		/* The regulator may on if it's not switchable or left on */
1281		ret = _regulator_is_enabled(rdev);
1282		if (ret == -EINVAL || ret == 0) {
1283			if (!_regulator_can_change_status(rdev))
1284				return -EPERM;
1285
1286			if (!rdev->desc->ops->enable)
1287				return -EINVAL;
1288
1289			/* Query before enabling in case configuration
1290			 * dependant.  */
1291			ret = _regulator_get_enable_time(rdev);
1292			if (ret >= 0) {
1293				delay = ret;
1294			} else {
1295				printk(KERN_WARNING
1296					"%s: enable_time() failed for %s: %d\n",
1297					__func__, rdev_get_name(rdev),
1298					ret);
1299				delay = 0;
1300			}
1301
1302			/* Allow the regulator to ramp; it would be useful
1303			 * to extend this for bulk operations so that the
1304			 * regulators can ramp together.  */
1305			ret = rdev->desc->ops->enable(rdev);
1306			if (ret < 0)
1307				return ret;
1308
1309			if (delay >= 1000)
1310				mdelay(delay / 1000);
1311			else if (delay)
1312				udelay(delay);
1313
1314		} else if (ret < 0) {
1315			printk(KERN_ERR "%s: is_enabled() failed for %s: %d\n",
1316			       __func__, rdev_get_name(rdev), ret);
1317			return ret;
1318		}
1319		/* Fallthrough on positive return values - already enabled */
1320	}
1321
1322	rdev->use_count++;
1323
1324	return 0;
1325}
1326
1327/**
1328 * regulator_enable - enable regulator output
1329 * @regulator: regulator source
1330 *
1331 * Request that the regulator be enabled with the regulator output at
1332 * the predefined voltage or current value.  Calls to regulator_enable()
1333 * must be balanced with calls to regulator_disable().
1334 *
1335 * NOTE: the output value can be set by other drivers, boot loader or may be
1336 * hardwired in the regulator.
1337 */
1338int regulator_enable(struct regulator *regulator)
1339{
1340	struct regulator_dev *rdev = regulator->rdev;
1341	int ret = 0;
1342
1343	mutex_lock(&rdev->mutex);
1344	ret = _regulator_enable(rdev);
1345	mutex_unlock(&rdev->mutex);
1346	return ret;
1347}
1348EXPORT_SYMBOL_GPL(regulator_enable);
1349
1350/* locks held by regulator_disable() */
1351static int _regulator_disable(struct regulator_dev *rdev)
1352{
1353	int ret = 0;
1354
1355	if (WARN(rdev->use_count <= 0,
1356			"unbalanced disables for %s\n",
1357			rdev_get_name(rdev)))
1358		return -EIO;
1359
1360	/* are we the last user and permitted to disable ? */
1361	if (rdev->use_count == 1 &&
1362	    (rdev->constraints && !rdev->constraints->always_on)) {
1363
1364		/* we are last user */
1365		if (_regulator_can_change_status(rdev) &&
1366		    rdev->desc->ops->disable) {
1367			ret = rdev->desc->ops->disable(rdev);
1368			if (ret < 0) {
1369				printk(KERN_ERR "%s: failed to disable %s\n",
1370				       __func__, rdev_get_name(rdev));
1371				return ret;
1372			}
1373
1374			_notifier_call_chain(rdev, REGULATOR_EVENT_DISABLE,
1375					     NULL);
1376		}
1377
1378		/* decrease our supplies ref count and disable if required */
1379		if (rdev->supply)
1380			_regulator_disable(rdev->supply);
1381
1382		rdev->use_count = 0;
1383	} else if (rdev->use_count > 1) {
1384
1385		if (rdev->constraints &&
1386			(rdev->constraints->valid_ops_mask &
1387			REGULATOR_CHANGE_DRMS))
1388			drms_uA_update(rdev);
1389
1390		rdev->use_count--;
1391	}
1392	return ret;
1393}
1394
1395/**
1396 * regulator_disable - disable regulator output
1397 * @regulator: regulator source
1398 *
1399 * Disable the regulator output voltage or current.  Calls to
1400 * regulator_enable() must be balanced with calls to
1401 * regulator_disable().
1402 *
1403 * NOTE: this will only disable the regulator output if no other consumer
1404 * devices have it enabled, the regulator device supports disabling and
1405 * machine constraints permit this operation.
1406 */
1407int regulator_disable(struct regulator *regulator)
1408{
1409	struct regulator_dev *rdev = regulator->rdev;
1410	int ret = 0;
1411
1412	mutex_lock(&rdev->mutex);
1413	ret = _regulator_disable(rdev);
1414	mutex_unlock(&rdev->mutex);
1415	return ret;
1416}
1417EXPORT_SYMBOL_GPL(regulator_disable);
1418
1419/* locks held by regulator_force_disable() */
1420static int _regulator_force_disable(struct regulator_dev *rdev)
1421{
1422	int ret = 0;
1423
1424	/* force disable */
1425	if (rdev->desc->ops->disable) {
1426		/* ah well, who wants to live forever... */
1427		ret = rdev->desc->ops->disable(rdev);
1428		if (ret < 0) {
1429			printk(KERN_ERR "%s: failed to force disable %s\n",
1430			       __func__, rdev_get_name(rdev));
1431			return ret;
1432		}
1433		/* notify other consumers that power has been forced off */
1434		_notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
1435			REGULATOR_EVENT_DISABLE, NULL);
1436	}
1437
1438	/* decrease our supplies ref count and disable if required */
1439	if (rdev->supply)
1440		_regulator_disable(rdev->supply);
1441
1442	rdev->use_count = 0;
1443	return ret;
1444}
1445
1446/**
1447 * regulator_force_disable - force disable regulator output
1448 * @regulator: regulator source
1449 *
1450 * Forcibly disable the regulator output voltage or current.
1451 * NOTE: this *will* disable the regulator output even if other consumer
1452 * devices have it enabled. This should be used for situations when device
1453 * damage will likely occur if the regulator is not disabled (e.g. over temp).
1454 */
1455int regulator_force_disable(struct regulator *regulator)
1456{
1457	int ret;
1458
1459	mutex_lock(&regulator->rdev->mutex);
1460	regulator->uA_load = 0;
1461	ret = _regulator_force_disable(regulator->rdev);
1462	mutex_unlock(&regulator->rdev->mutex);
1463	return ret;
1464}
1465EXPORT_SYMBOL_GPL(regulator_force_disable);
1466
1467static int _regulator_is_enabled(struct regulator_dev *rdev)
1468{
1469	/* sanity check */
1470	if (!rdev->desc->ops->is_enabled)
1471		return -EINVAL;
1472
1473	return rdev->desc->ops->is_enabled(rdev);
1474}
1475
1476/**
1477 * regulator_is_enabled - is the regulator output enabled
1478 * @regulator: regulator source
1479 *
1480 * Returns positive if the regulator driver backing the source/client
1481 * has requested that the device be enabled, zero if it hasn't, else a
1482 * negative errno code.
1483 *
1484 * Note that the device backing this regulator handle can have multiple
1485 * users, so it might be enabled even if regulator_enable() was never
1486 * called for this particular source.
1487 */
1488int regulator_is_enabled(struct regulator *regulator)
1489{
1490	int ret;
1491
1492	mutex_lock(&regulator->rdev->mutex);
1493	ret = _regulator_is_enabled(regulator->rdev);
1494	mutex_unlock(&regulator->rdev->mutex);
1495
1496	return ret;
1497}
1498EXPORT_SYMBOL_GPL(regulator_is_enabled);
1499
1500/**
1501 * regulator_count_voltages - count regulator_list_voltage() selectors
1502 * @regulator: regulator source
1503 *
1504 * Returns number of selectors, or negative errno.  Selectors are
1505 * numbered starting at zero, and typically correspond to bitfields
1506 * in hardware registers.
1507 */
1508int regulator_count_voltages(struct regulator *regulator)
1509{
1510	struct regulator_dev	*rdev = regulator->rdev;
1511
1512	return rdev->desc->n_voltages ? : -EINVAL;
1513}
1514EXPORT_SYMBOL_GPL(regulator_count_voltages);
1515
1516/**
1517 * regulator_list_voltage - enumerate supported voltages
1518 * @regulator: regulator source
1519 * @selector: identify voltage to list
1520 * Context: can sleep
1521 *
1522 * Returns a voltage that can be passed to @regulator_set_voltage(),
1523 * zero if this selector code can't be used on this sytem, or a
1524 * negative errno.
1525 */
1526int regulator_list_voltage(struct regulator *regulator, unsigned selector)
1527{
1528	struct regulator_dev	*rdev = regulator->rdev;
1529	struct regulator_ops	*ops = rdev->desc->ops;
1530	int			ret;
1531
1532	if (!ops->list_voltage || selector >= rdev->desc->n_voltages)
1533		return -EINVAL;
1534
1535	mutex_lock(&rdev->mutex);
1536	ret = ops->list_voltage(rdev, selector);
1537	mutex_unlock(&rdev->mutex);
1538
1539	if (ret > 0) {
1540		if (ret < rdev->constraints->min_uV)
1541			ret = 0;
1542		else if (ret > rdev->constraints->max_uV)
1543			ret = 0;
1544	}
1545
1546	return ret;
1547}
1548EXPORT_SYMBOL_GPL(regulator_list_voltage);
1549
1550/**
1551 * regulator_is_supported_voltage - check if a voltage range can be supported
1552 *
1553 * @regulator: Regulator to check.
1554 * @min_uV: Minimum required voltage in uV.
1555 * @max_uV: Maximum required voltage in uV.
1556 *
1557 * Returns a boolean or a negative error code.
1558 */
1559int regulator_is_supported_voltage(struct regulator *regulator,
1560				   int min_uV, int max_uV)
1561{
1562	int i, voltages, ret;
1563
1564	ret = regulator_count_voltages(regulator);
1565	if (ret < 0)
1566		return ret;
1567	voltages = ret;
1568
1569	for (i = 0; i < voltages; i++) {
1570		ret = regulator_list_voltage(regulator, i);
1571
1572		if (ret >= min_uV && ret <= max_uV)
1573			return 1;
1574	}
1575
1576	return 0;
1577}
1578
1579/**
1580 * regulator_set_voltage - set regulator output voltage
1581 * @regulator: regulator source
1582 * @min_uV: Minimum required voltage in uV
1583 * @max_uV: Maximum acceptable voltage in uV
1584 *
1585 * Sets a voltage regulator to the desired output voltage. This can be set
1586 * during any regulator state. IOW, regulator can be disabled or enabled.
1587 *
1588 * If the regulator is enabled then the voltage will change to the new value
1589 * immediately otherwise if the regulator is disabled the regulator will
1590 * output at the new voltage when enabled.
1591 *
1592 * NOTE: If the regulator is shared between several devices then the lowest
1593 * request voltage that meets the system constraints will be used.
1594 * Regulator system constraints must be set for this regulator before
1595 * calling this function otherwise this call will fail.
1596 */
1597int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
1598{
1599	struct regulator_dev *rdev = regulator->rdev;
1600	int ret;
1601
1602	mutex_lock(&rdev->mutex);
1603
1604	/* sanity check */
1605	if (!rdev->desc->ops->set_voltage) {
1606		ret = -EINVAL;
1607		goto out;
1608	}
1609
1610	/* constraints check */
1611	ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
1612	if (ret < 0)
1613		goto out;
1614	regulator->min_uV = min_uV;
1615	regulator->max_uV = max_uV;
1616	ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV);
1617
1618out:
1619	_notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE, NULL);
1620	mutex_unlock(&rdev->mutex);
1621	return ret;
1622}
1623EXPORT_SYMBOL_GPL(regulator_set_voltage);
1624
1625static int _regulator_get_voltage(struct regulator_dev *rdev)
1626{
1627	/* sanity check */
1628	if (rdev->desc->ops->get_voltage)
1629		return rdev->desc->ops->get_voltage(rdev);
1630	else
1631		return -EINVAL;
1632}
1633
1634/**
1635 * regulator_get_voltage - get regulator output voltage
1636 * @regulator: regulator source
1637 *
1638 * This returns the current regulator voltage in uV.
1639 *
1640 * NOTE: If the regulator is disabled it will return the voltage value. This
1641 * function should not be used to determine regulator state.
1642 */
1643int regulator_get_voltage(struct regulator *regulator)
1644{
1645	int ret;
1646
1647	mutex_lock(&regulator->rdev->mutex);
1648
1649	ret = _regulator_get_voltage(regulator->rdev);
1650
1651	mutex_unlock(&regulator->rdev->mutex);
1652
1653	return ret;
1654}
1655EXPORT_SYMBOL_GPL(regulator_get_voltage);
1656
1657/**
1658 * regulator_set_current_limit - set regulator output current limit
1659 * @regulator: regulator source
1660 * @min_uA: Minimuum supported current in uA
1661 * @max_uA: Maximum supported current in uA
1662 *
1663 * Sets current sink to the desired output current. This can be set during
1664 * any regulator state. IOW, regulator can be disabled or enabled.
1665 *
1666 * If the regulator is enabled then the current will change to the new value
1667 * immediately otherwise if the regulator is disabled the regulator will
1668 * output at the new current when enabled.
1669 *
1670 * NOTE: Regulator system constraints must be set for this regulator before
1671 * calling this function otherwise this call will fail.
1672 */
1673int regulator_set_current_limit(struct regulator *regulator,
1674			       int min_uA, int max_uA)
1675{
1676	struct regulator_dev *rdev = regulator->rdev;
1677	int ret;
1678
1679	mutex_lock(&rdev->mutex);
1680
1681	/* sanity check */
1682	if (!rdev->desc->ops->set_current_limit) {
1683		ret = -EINVAL;
1684		goto out;
1685	}
1686
1687	/* constraints check */
1688	ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
1689	if (ret < 0)
1690		goto out;
1691
1692	ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
1693out:
1694	mutex_unlock(&rdev->mutex);
1695	return ret;
1696}
1697EXPORT_SYMBOL_GPL(regulator_set_current_limit);
1698
1699static int _regulator_get_current_limit(struct regulator_dev *rdev)
1700{
1701	int ret;
1702
1703	mutex_lock(&rdev->mutex);
1704
1705	/* sanity check */
1706	if (!rdev->desc->ops->get_current_limit) {
1707		ret = -EINVAL;
1708		goto out;
1709	}
1710
1711	ret = rdev->desc->ops->get_current_limit(rdev);
1712out:
1713	mutex_unlock(&rdev->mutex);
1714	return ret;
1715}
1716
1717/**
1718 * regulator_get_current_limit - get regulator output current
1719 * @regulator: regulator source
1720 *
1721 * This returns the current supplied by the specified current sink in uA.
1722 *
1723 * NOTE: If the regulator is disabled it will return the current value. This
1724 * function should not be used to determine regulator state.
1725 */
1726int regulator_get_current_limit(struct regulator *regulator)
1727{
1728	return _regulator_get_current_limit(regulator->rdev);
1729}
1730EXPORT_SYMBOL_GPL(regulator_get_current_limit);
1731
1732/**
1733 * regulator_set_mode - set regulator operating mode
1734 * @regulator: regulator source
1735 * @mode: operating mode - one of the REGULATOR_MODE constants
1736 *
1737 * Set regulator operating mode to increase regulator efficiency or improve
1738 * regulation performance.
1739 *
1740 * NOTE: Regulator system constraints must be set for this regulator before
1741 * calling this function otherwise this call will fail.
1742 */
1743int regulator_set_mode(struct regulator *regulator, unsigned int mode)
1744{
1745	struct regulator_dev *rdev = regulator->rdev;
1746	int ret;
1747
1748	mutex_lock(&rdev->mutex);
1749
1750	/* sanity check */
1751	if (!rdev->desc->ops->set_mode) {
1752		ret = -EINVAL;
1753		goto out;
1754	}
1755
1756	/* constraints check */
1757	ret = regulator_check_mode(rdev, mode);
1758	if (ret < 0)
1759		goto out;
1760
1761	ret = rdev->desc->ops->set_mode(rdev, mode);
1762out:
1763	mutex_unlock(&rdev->mutex);
1764	return ret;
1765}
1766EXPORT_SYMBOL_GPL(regulator_set_mode);
1767
1768static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
1769{
1770	int ret;
1771
1772	mutex_lock(&rdev->mutex);
1773
1774	/* sanity check */
1775	if (!rdev->desc->ops->get_mode) {
1776		ret = -EINVAL;
1777		goto out;
1778	}
1779
1780	ret = rdev->desc->ops->get_mode(rdev);
1781out:
1782	mutex_unlock(&rdev->mutex);
1783	return ret;
1784}
1785
1786/**
1787 * regulator_get_mode - get regulator operating mode
1788 * @regulator: regulator source
1789 *
1790 * Get the current regulator operating mode.
1791 */
1792unsigned int regulator_get_mode(struct regulator *regulator)
1793{
1794	return _regulator_get_mode(regulator->rdev);
1795}
1796EXPORT_SYMBOL_GPL(regulator_get_mode);
1797
1798/**
1799 * regulator_set_optimum_mode - set regulator optimum operating mode
1800 * @regulator: regulator source
1801 * @uA_load: load current
1802 *
1803 * Notifies the regulator core of a new device load. This is then used by
1804 * DRMS (if enabled by constraints) to set the most efficient regulator
1805 * operating mode for the new regulator loading.
1806 *
1807 * Consumer devices notify their supply regulator of the maximum power
1808 * they will require (can be taken from device datasheet in the power
1809 * consumption tables) when they change operational status and hence power
1810 * state. Examples of operational state changes that can affect power
1811 * consumption are :-
1812 *
1813 *    o Device is opened / closed.
1814 *    o Device I/O is about to begin or has just finished.
1815 *    o Device is idling in between work.
1816 *
1817 * This information is also exported via sysfs to userspace.
1818 *
1819 * DRMS will sum the total requested load on the regulator and change
1820 * to the most efficient operating mode if platform constraints allow.
1821 *
1822 * Returns the new regulator mode or error.
1823 */
1824int regulator_set_optimum_mode(struct regulator *regulator, int uA_load)
1825{
1826	struct regulator_dev *rdev = regulator->rdev;
1827	struct regulator *consumer;
1828	int ret, output_uV, input_uV, total_uA_load = 0;
1829	unsigned int mode;
1830
1831	mutex_lock(&rdev->mutex);
1832
1833	regulator->uA_load = uA_load;
1834	ret = regulator_check_drms(rdev);
1835	if (ret < 0)
1836		goto out;
1837	ret = -EINVAL;
1838
1839	/* sanity check */
1840	if (!rdev->desc->ops->get_optimum_mode)
1841		goto out;
1842
1843	/* get output voltage */
1844	output_uV = rdev->desc->ops->get_voltage(rdev);
1845	if (output_uV <= 0) {
1846		printk(KERN_ERR "%s: invalid output voltage found for %s\n",
1847			__func__, rdev_get_name(rdev));
1848		goto out;
1849	}
1850
1851	/* get input voltage */
1852	if (rdev->supply && rdev->supply->desc->ops->get_voltage)
1853		input_uV = rdev->supply->desc->ops->get_voltage(rdev->supply);
1854	else
1855		input_uV = rdev->constraints->input_uV;
1856	if (input_uV <= 0) {
1857		printk(KERN_ERR "%s: invalid input voltage found for %s\n",
1858			__func__, rdev_get_name(rdev));
1859		goto out;
1860	}
1861
1862	/* calc total requested load for this regulator */
1863	list_for_each_entry(consumer, &rdev->consumer_list, list)
1864		total_uA_load += consumer->uA_load;
1865
1866	mode = rdev->desc->ops->get_optimum_mode(rdev,
1867						 input_uV, output_uV,
1868						 total_uA_load);
1869	ret = regulator_check_mode(rdev, mode);
1870	if (ret < 0) {
1871		printk(KERN_ERR "%s: failed to get optimum mode for %s @"
1872			" %d uA %d -> %d uV\n", __func__, rdev_get_name(rdev),
1873			total_uA_load, input_uV, output_uV);
1874		goto out;
1875	}
1876
1877	ret = rdev->desc->ops->set_mode(rdev, mode);
1878	if (ret < 0) {
1879		printk(KERN_ERR "%s: failed to set optimum mode %x for %s\n",
1880			__func__, mode, rdev_get_name(rdev));
1881		goto out;
1882	}
1883	ret = mode;
1884out:
1885	mutex_unlock(&rdev->mutex);
1886	return ret;
1887}
1888EXPORT_SYMBOL_GPL(regulator_set_optimum_mode);
1889
1890/**
1891 * regulator_register_notifier - register regulator event notifier
1892 * @regulator: regulator source
1893 * @nb: notifier block
1894 *
1895 * Register notifier block to receive regulator events.
1896 */
1897int regulator_register_notifier(struct regulator *regulator,
1898			      struct notifier_block *nb)
1899{
1900	return blocking_notifier_chain_register(&regulator->rdev->notifier,
1901						nb);
1902}
1903EXPORT_SYMBOL_GPL(regulator_register_notifier);
1904
1905/**
1906 * regulator_unregister_notifier - unregister regulator event notifier
1907 * @regulator: regulator source
1908 * @nb: notifier block
1909 *
1910 * Unregister regulator event notifier block.
1911 */
1912int regulator_unregister_notifier(struct regulator *regulator,
1913				struct notifier_block *nb)
1914{
1915	return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
1916						  nb);
1917}
1918EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
1919
1920/* notify regulator consumers and downstream regulator consumers.
1921 * Note mutex must be held by caller.
1922 */
1923static void _notifier_call_chain(struct regulator_dev *rdev,
1924				  unsigned long event, void *data)
1925{
1926	struct regulator_dev *_rdev;
1927
1928	/* call rdev chain first */
1929	blocking_notifier_call_chain(&rdev->notifier, event, NULL);
1930
1931	/* now notify regulator we supply */
1932	list_for_each_entry(_rdev, &rdev->supply_list, slist) {
1933		mutex_lock(&_rdev->mutex);
1934		_notifier_call_chain(_rdev, event, data);
1935		mutex_unlock(&_rdev->mutex);
1936	}
1937}
1938
1939/**
1940 * regulator_bulk_get - get multiple regulator consumers
1941 *
1942 * @dev:           Device to supply
1943 * @num_consumers: Number of consumers to register
1944 * @consumers:     Configuration of consumers; clients are stored here.
1945 *
1946 * @return 0 on success, an errno on failure.
1947 *
1948 * This helper function allows drivers to get several regulator
1949 * consumers in one operation.  If any of the regulators cannot be
1950 * acquired then any regulators that were allocated will be freed
1951 * before returning to the caller.
1952 */
1953int regulator_bulk_get(struct device *dev, int num_consumers,
1954		       struct regulator_bulk_data *consumers)
1955{
1956	int i;
1957	int ret;
1958
1959	for (i = 0; i < num_consumers; i++)
1960		consumers[i].consumer = NULL;
1961
1962	for (i = 0; i < num_consumers; i++) {
1963		consumers[i].consumer = regulator_get(dev,
1964						      consumers[i].supply);
1965		if (IS_ERR(consumers[i].consumer)) {
1966			ret = PTR_ERR(consumers[i].consumer);
1967			dev_err(dev, "Failed to get supply '%s': %d\n",
1968				consumers[i].supply, ret);
1969			consumers[i].consumer = NULL;
1970			goto err;
1971		}
1972	}
1973
1974	return 0;
1975
1976err:
1977	for (i = 0; i < num_consumers && consumers[i].consumer; i++)
1978		regulator_put(consumers[i].consumer);
1979
1980	return ret;
1981}
1982EXPORT_SYMBOL_GPL(regulator_bulk_get);
1983
1984/**
1985 * regulator_bulk_enable - enable multiple regulator consumers
1986 *
1987 * @num_consumers: Number of consumers
1988 * @consumers:     Consumer data; clients are stored here.
1989 * @return         0 on success, an errno on failure
1990 *
1991 * This convenience API allows consumers to enable multiple regulator
1992 * clients in a single API call.  If any consumers cannot be enabled
1993 * then any others that were enabled will be disabled again prior to
1994 * return.
1995 */
1996int regulator_bulk_enable(int num_consumers,
1997			  struct regulator_bulk_data *consumers)
1998{
1999	int i;
2000	int ret;
2001
2002	for (i = 0; i < num_consumers; i++) {
2003		ret = regulator_enable(consumers[i].consumer);
2004		if (ret != 0)
2005			goto err;
2006	}
2007
2008	return 0;
2009
2010err:
2011	printk(KERN_ERR "Failed to enable %s: %d\n", consumers[i].supply, ret);
2012	for (--i; i >= 0; --i)
2013		regulator_disable(consumers[i].consumer);
2014
2015	return ret;
2016}
2017EXPORT_SYMBOL_GPL(regulator_bulk_enable);
2018
2019/**
2020 * regulator_bulk_disable - disable multiple regulator consumers
2021 *
2022 * @num_consumers: Number of consumers
2023 * @consumers:     Consumer data; clients are stored here.
2024 * @return         0 on success, an errno on failure
2025 *
2026 * This convenience API allows consumers to disable multiple regulator
2027 * clients in a single API call.  If any consumers cannot be enabled
2028 * then any others that were disabled will be disabled again prior to
2029 * return.
2030 */
2031int regulator_bulk_disable(int num_consumers,
2032			   struct regulator_bulk_data *consumers)
2033{
2034	int i;
2035	int ret;
2036
2037	for (i = 0; i < num_consumers; i++) {
2038		ret = regulator_disable(consumers[i].consumer);
2039		if (ret != 0)
2040			goto err;
2041	}
2042
2043	return 0;
2044
2045err:
2046	printk(KERN_ERR "Failed to disable %s: %d\n", consumers[i].supply,
2047	       ret);
2048	for (--i; i >= 0; --i)
2049		regulator_enable(consumers[i].consumer);
2050
2051	return ret;
2052}
2053EXPORT_SYMBOL_GPL(regulator_bulk_disable);
2054
2055/**
2056 * regulator_bulk_free - free multiple regulator consumers
2057 *
2058 * @num_consumers: Number of consumers
2059 * @consumers:     Consumer data; clients are stored here.
2060 *
2061 * This convenience API allows consumers to free multiple regulator
2062 * clients in a single API call.
2063 */
2064void regulator_bulk_free(int num_consumers,
2065			 struct regulator_bulk_data *consumers)
2066{
2067	int i;
2068
2069	for (i = 0; i < num_consumers; i++) {
2070		regulator_put(consumers[i].consumer);
2071		consumers[i].consumer = NULL;
2072	}
2073}
2074EXPORT_SYMBOL_GPL(regulator_bulk_free);
2075
2076/**
2077 * regulator_notifier_call_chain - call regulator event notifier
2078 * @rdev: regulator source
2079 * @event: notifier block
2080 * @data: callback-specific data.
2081 *
2082 * Called by regulator drivers to notify clients a regulator event has
2083 * occurred. We also notify regulator clients downstream.
2084 * Note lock must be held by caller.
2085 */
2086int regulator_notifier_call_chain(struct regulator_dev *rdev,
2087				  unsigned long event, void *data)
2088{
2089	_notifier_call_chain(rdev, event, data);
2090	return NOTIFY_DONE;
2091
2092}
2093EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
2094
2095/**
2096 * regulator_mode_to_status - convert a regulator mode into a status
2097 *
2098 * @mode: Mode to convert
2099 *
2100 * Convert a regulator mode into a status.
2101 */
2102int regulator_mode_to_status(unsigned int mode)
2103{
2104	switch (mode) {
2105	case REGULATOR_MODE_FAST:
2106		return REGULATOR_STATUS_FAST;
2107	case REGULATOR_MODE_NORMAL:
2108		return REGULATOR_STATUS_NORMAL;
2109	case REGULATOR_MODE_IDLE:
2110		return REGULATOR_STATUS_IDLE;
2111	case REGULATOR_STATUS_STANDBY:
2112		return REGULATOR_STATUS_STANDBY;
2113	default:
2114		return 0;
2115	}
2116}
2117EXPORT_SYMBOL_GPL(regulator_mode_to_status);
2118
2119/*
2120 * To avoid cluttering sysfs (and memory) with useless state, only
2121 * create attributes that can be meaningfully displayed.
2122 */
2123static int add_regulator_attributes(struct regulator_dev *rdev)
2124{
2125	struct device		*dev = &rdev->dev;
2126	struct regulator_ops	*ops = rdev->desc->ops;
2127	int			status = 0;
2128
2129	/* some attributes need specific methods to be displayed */
2130	if (ops->get_voltage) {
2131		status = device_create_file(dev, &dev_attr_microvolts);
2132		if (status < 0)
2133			return status;
2134	}
2135	if (ops->get_current_limit) {
2136		status = device_create_file(dev, &dev_attr_microamps);
2137		if (status < 0)
2138			return status;
2139	}
2140	if (ops->get_mode) {
2141		status = device_create_file(dev, &dev_attr_opmode);
2142		if (status < 0)
2143			return status;
2144	}
2145	if (ops->is_enabled) {
2146		status = device_create_file(dev, &dev_attr_state);
2147		if (status < 0)
2148			return status;
2149	}
2150	if (ops->get_status) {
2151		status = device_create_file(dev, &dev_attr_status);
2152		if (status < 0)
2153			return status;
2154	}
2155
2156	/* some attributes are type-specific */
2157	if (rdev->desc->type == REGULATOR_CURRENT) {
2158		status = device_create_file(dev, &dev_attr_requested_microamps);
2159		if (status < 0)
2160			return status;
2161	}
2162
2163	/* all the other attributes exist to support constraints;
2164	 * don't show them if there are no constraints, or if the
2165	 * relevant supporting methods are missing.
2166	 */
2167	if (!rdev->constraints)
2168		return status;
2169
2170	/* constraints need specific supporting methods */
2171	if (ops->set_voltage) {
2172		status = device_create_file(dev, &dev_attr_min_microvolts);
2173		if (status < 0)
2174			return status;
2175		status = device_create_file(dev, &dev_attr_max_microvolts);
2176		if (status < 0)
2177			return status;
2178	}
2179	if (ops->set_current_limit) {
2180		status = device_create_file(dev, &dev_attr_min_microamps);
2181		if (status < 0)
2182			return status;
2183		status = device_create_file(dev, &dev_attr_max_microamps);
2184		if (status < 0)
2185			return status;
2186	}
2187
2188	/* suspend mode constraints need multiple supporting methods */
2189	if (!(ops->set_suspend_enable && ops->set_suspend_disable))
2190		return status;
2191
2192	status = device_create_file(dev, &dev_attr_suspend_standby_state);
2193	if (status < 0)
2194		return status;
2195	status = device_create_file(dev, &dev_attr_suspend_mem_state);
2196	if (status < 0)
2197		return status;
2198	status = device_create_file(dev, &dev_attr_suspend_disk_state);
2199	if (status < 0)
2200		return status;
2201
2202	if (ops->set_suspend_voltage) {
2203		status = device_create_file(dev,
2204				&dev_attr_suspend_standby_microvolts);
2205		if (status < 0)
2206			return status;
2207		status = device_create_file(dev,
2208				&dev_attr_suspend_mem_microvolts);
2209		if (status < 0)
2210			return status;
2211		status = device_create_file(dev,
2212				&dev_attr_suspend_disk_microvolts);
2213		if (status < 0)
2214			return status;
2215	}
2216
2217	if (ops->set_suspend_mode) {
2218		status = device_create_file(dev,
2219				&dev_attr_suspend_standby_mode);
2220		if (status < 0)
2221			return status;
2222		status = device_create_file(dev,
2223				&dev_attr_suspend_mem_mode);
2224		if (status < 0)
2225			return status;
2226		status = device_create_file(dev,
2227				&dev_attr_suspend_disk_mode);
2228		if (status < 0)
2229			return status;
2230	}
2231
2232	return status;
2233}
2234
2235/**
2236 * regulator_register - register regulator
2237 * @regulator_desc: regulator to register
2238 * @dev: struct device for the regulator
2239 * @init_data: platform provided init data, passed through by driver
2240 * @driver_data: private regulator data
2241 *
2242 * Called by regulator drivers to register a regulator.
2243 * Returns 0 on success.
2244 */
2245struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc,
2246	struct device *dev, struct regulator_init_data *init_data,
2247	void *driver_data)
2248{
2249	static atomic_t regulator_no = ATOMIC_INIT(0);
2250	struct regulator_dev *rdev;
2251	int ret, i;
2252
2253	if (regulator_desc == NULL)
2254		return ERR_PTR(-EINVAL);
2255
2256	if (regulator_desc->name == NULL || regulator_desc->ops == NULL)
2257		return ERR_PTR(-EINVAL);
2258
2259	if (regulator_desc->type != REGULATOR_VOLTAGE &&
2260	    regulator_desc->type != REGULATOR_CURRENT)
2261		return ERR_PTR(-EINVAL);
2262
2263	if (!init_data)
2264		return ERR_PTR(-EINVAL);
2265
2266	rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
2267	if (rdev == NULL)
2268		return ERR_PTR(-ENOMEM);
2269
2270	mutex_lock(&regulator_list_mutex);
2271
2272	mutex_init(&rdev->mutex);
2273	rdev->reg_data = driver_data;
2274	rdev->owner = regulator_desc->owner;
2275	rdev->desc = regulator_desc;
2276	INIT_LIST_HEAD(&rdev->consumer_list);
2277	INIT_LIST_HEAD(&rdev->supply_list);
2278	INIT_LIST_HEAD(&rdev->list);
2279	INIT_LIST_HEAD(&rdev->slist);
2280	BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
2281
2282	/* preform any regulator specific init */
2283	if (init_data->regulator_init) {
2284		ret = init_data->regulator_init(rdev->reg_data);
2285		if (ret < 0)
2286			goto clean;
2287	}
2288
2289	/* register with sysfs */
2290	rdev->dev.class = &regulator_class;
2291	rdev->dev.parent = dev;
2292	dev_set_name(&rdev->dev, "regulator.%d",
2293		     atomic_inc_return(&regulator_no) - 1);
2294	ret = device_register(&rdev->dev);
2295	if (ret != 0)
2296		goto clean;
2297
2298	dev_set_drvdata(&rdev->dev, rdev);
2299
2300	/* set regulator constraints */
2301	ret = set_machine_constraints(rdev, &init_data->constraints);
2302	if (ret < 0)
2303		goto scrub;
2304
2305	/* add attributes supported by this regulator */
2306	ret = add_regulator_attributes(rdev);
2307	if (ret < 0)
2308		goto scrub;
2309
2310	/* set supply regulator if it exists */
2311	if (init_data->supply_regulator_dev) {
2312		ret = set_supply(rdev,
2313			dev_get_drvdata(init_data->supply_regulator_dev));
2314		if (ret < 0)
2315			goto scrub;
2316	}
2317
2318	/* add consumers devices */
2319	for (i = 0; i < init_data->num_consumer_supplies; i++) {
2320		ret = set_consumer_device_supply(rdev,
2321			init_data->consumer_supplies[i].dev,
2322			init_data->consumer_supplies[i].dev_name,
2323			init_data->consumer_supplies[i].supply);
2324		if (ret < 0) {
2325			for (--i; i >= 0; i--)
2326				unset_consumer_device_supply(rdev,
2327				    init_data->consumer_supplies[i].dev_name,
2328				    init_data->consumer_supplies[i].dev);
2329			goto scrub;
2330		}
2331	}
2332
2333	list_add(&rdev->list, &regulator_list);
2334out:
2335	mutex_unlock(&regulator_list_mutex);
2336	return rdev;
2337
2338scrub:
2339	device_unregister(&rdev->dev);
2340	/* device core frees rdev */
2341	rdev = ERR_PTR(ret);
2342	goto out;
2343
2344clean:
2345	kfree(rdev);
2346	rdev = ERR_PTR(ret);
2347	goto out;
2348}
2349EXPORT_SYMBOL_GPL(regulator_register);
2350
2351/**
2352 * regulator_unregister - unregister regulator
2353 * @rdev: regulator to unregister
2354 *
2355 * Called by regulator drivers to unregister a regulator.
2356 */
2357void regulator_unregister(struct regulator_dev *rdev)
2358{
2359	if (rdev == NULL)
2360		return;
2361
2362	mutex_lock(&regulator_list_mutex);
2363	WARN_ON(rdev->open_count);
2364	unset_regulator_supplies(rdev);
2365	list_del(&rdev->list);
2366	if (rdev->supply)
2367		sysfs_remove_link(&rdev->dev.kobj, "supply");
2368	device_unregister(&rdev->dev);
2369	mutex_unlock(&regulator_list_mutex);
2370}
2371EXPORT_SYMBOL_GPL(regulator_unregister);
2372
2373/**
2374 * regulator_suspend_prepare - prepare regulators for system wide suspend
2375 * @state: system suspend state
2376 *
2377 * Configure each regulator with it's suspend operating parameters for state.
2378 * This will usually be called by machine suspend code prior to supending.
2379 */
2380int regulator_suspend_prepare(suspend_state_t state)
2381{
2382	struct regulator_dev *rdev;
2383	int ret = 0;
2384
2385	/* ON is handled by regulator active state */
2386	if (state == PM_SUSPEND_ON)
2387		return -EINVAL;
2388
2389	mutex_lock(&regulator_list_mutex);
2390	list_for_each_entry(rdev, &regulator_list, list) {
2391
2392		mutex_lock(&rdev->mutex);
2393		ret = suspend_prepare(rdev, state);
2394		mutex_unlock(&rdev->mutex);
2395
2396		if (ret < 0) {
2397			printk(KERN_ERR "%s: failed to prepare %s\n",
2398				__func__, rdev_get_name(rdev));
2399			goto out;
2400		}
2401	}
2402out:
2403	mutex_unlock(&regulator_list_mutex);
2404	return ret;
2405}
2406EXPORT_SYMBOL_GPL(regulator_suspend_prepare);
2407
2408/**
2409 * regulator_has_full_constraints - the system has fully specified constraints
2410 *
2411 * Calling this function will cause the regulator API to disable all
2412 * regulators which have a zero use count and don't have an always_on
2413 * constraint in a late_initcall.
2414 *
2415 * The intention is that this will become the default behaviour in a
2416 * future kernel release so users are encouraged to use this facility
2417 * now.
2418 */
2419void regulator_has_full_constraints(void)
2420{
2421	has_full_constraints = 1;
2422}
2423EXPORT_SYMBOL_GPL(regulator_has_full_constraints);
2424
2425/**
2426 * rdev_get_drvdata - get rdev regulator driver data
2427 * @rdev: regulator
2428 *
2429 * Get rdev regulator driver private data. This call can be used in the
2430 * regulator driver context.
2431 */
2432void *rdev_get_drvdata(struct regulator_dev *rdev)
2433{
2434	return rdev->reg_data;
2435}
2436EXPORT_SYMBOL_GPL(rdev_get_drvdata);
2437
2438/**
2439 * regulator_get_drvdata - get regulator driver data
2440 * @regulator: regulator
2441 *
2442 * Get regulator driver private data. This call can be used in the consumer
2443 * driver context when non API regulator specific functions need to be called.
2444 */
2445void *regulator_get_drvdata(struct regulator *regulator)
2446{
2447	return regulator->rdev->reg_data;
2448}
2449EXPORT_SYMBOL_GPL(regulator_get_drvdata);
2450
2451/**
2452 * regulator_set_drvdata - set regulator driver data
2453 * @regulator: regulator
2454 * @data: data
2455 */
2456void regulator_set_drvdata(struct regulator *regulator, void *data)
2457{
2458	regulator->rdev->reg_data = data;
2459}
2460EXPORT_SYMBOL_GPL(regulator_set_drvdata);
2461
2462/**
2463 * regulator_get_id - get regulator ID
2464 * @rdev: regulator
2465 */
2466int rdev_get_id(struct regulator_dev *rdev)
2467{
2468	return rdev->desc->id;
2469}
2470EXPORT_SYMBOL_GPL(rdev_get_id);
2471
2472struct device *rdev_get_dev(struct regulator_dev *rdev)
2473{
2474	return &rdev->dev;
2475}
2476EXPORT_SYMBOL_GPL(rdev_get_dev);
2477
2478void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
2479{
2480	return reg_init_data->driver_data;
2481}
2482EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
2483
2484static int __init regulator_init(void)
2485{
2486	printk(KERN_INFO "regulator: core version %s\n", REGULATOR_VERSION);
2487	return class_register(&regulator_class);
2488}
2489
2490/* init early to allow our consumers to complete system booting */
2491core_initcall(regulator_init);
2492
2493static int __init regulator_init_complete(void)
2494{
2495	struct regulator_dev *rdev;
2496	struct regulator_ops *ops;
2497	struct regulation_constraints *c;
2498	int enabled, ret;
2499	const char *name;
2500
2501	mutex_lock(&regulator_list_mutex);
2502
2503	/* If we have a full configuration then disable any regulators
2504	 * which are not in use or always_on.  This will become the
2505	 * default behaviour in the future.
2506	 */
2507	list_for_each_entry(rdev, &regulator_list, list) {
2508		ops = rdev->desc->ops;
2509		c = rdev->constraints;
2510
2511		name = rdev_get_name(rdev);
2512
2513		if (!ops->disable || (c && c->always_on))
2514			continue;
2515
2516		mutex_lock(&rdev->mutex);
2517
2518		if (rdev->use_count)
2519			goto unlock;
2520
2521		/* If we can't read the status assume it's on. */
2522		if (ops->is_enabled)
2523			enabled = ops->is_enabled(rdev);
2524		else
2525			enabled = 1;
2526
2527		if (!enabled)
2528			goto unlock;
2529
2530		if (has_full_constraints) {
2531			/* We log since this may kill the system if it
2532			 * goes wrong. */
2533			printk(KERN_INFO "%s: disabling %s\n",
2534			       __func__, name);
2535			ret = ops->disable(rdev);
2536			if (ret != 0) {
2537				printk(KERN_ERR
2538				       "%s: couldn't disable %s: %d\n",
2539				       __func__, name, ret);
2540			}
2541		} else {
2542			/* The intention is that in future we will
2543			 * assume that full constraints are provided
2544			 * so warn even if we aren't going to do
2545			 * anything here.
2546			 */
2547			printk(KERN_WARNING
2548			       "%s: incomplete constraints, leaving %s on\n",
2549			       __func__, name);
2550		}
2551
2552unlock:
2553		mutex_unlock(&rdev->mutex);
2554	}
2555
2556	mutex_unlock(&regulator_list_mutex);
2557
2558	return 0;
2559}
2560late_initcall(regulator_init_complete);
2561