core.c revision 068a2782f59efe5855091860bbccbadf1c72fffd
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/slab.h>
20#include <linux/err.h>
21#include <linux/mutex.h>
22#include <linux/suspend.h>
23#include <linux/delay.h>
24#include <linux/regulator/consumer.h>
25#include <linux/regulator/driver.h>
26#include <linux/regulator/machine.h>
27
28#include "dummy.h"
29
30#define REGULATOR_VERSION "0.5"
31
32static DEFINE_MUTEX(regulator_list_mutex);
33static LIST_HEAD(regulator_list);
34static LIST_HEAD(regulator_map_list);
35static int has_full_constraints;
36
37/*
38 * struct regulator_map
39 *
40 * Used to provide symbolic supply names to devices.
41 */
42struct regulator_map {
43	struct list_head list;
44	const char *dev_name;   /* The dev_name() for the consumer */
45	const char *supply;
46	struct regulator_dev *regulator;
47};
48
49/*
50 * struct regulator
51 *
52 * One for each consumer device.
53 */
54struct regulator {
55	struct device *dev;
56	struct list_head list;
57	int uA_load;
58	int min_uV;
59	int max_uV;
60	char *supply_name;
61	struct device_attribute dev_attr;
62	struct regulator_dev *rdev;
63};
64
65static int _regulator_is_enabled(struct regulator_dev *rdev);
66static int _regulator_disable(struct regulator_dev *rdev);
67static int _regulator_get_voltage(struct regulator_dev *rdev);
68static int _regulator_get_current_limit(struct regulator_dev *rdev);
69static unsigned int _regulator_get_mode(struct regulator_dev *rdev);
70static void _notifier_call_chain(struct regulator_dev *rdev,
71				  unsigned long event, void *data);
72
73static const char *rdev_get_name(struct regulator_dev *rdev)
74{
75	if (rdev->constraints && rdev->constraints->name)
76		return rdev->constraints->name;
77	else if (rdev->desc->name)
78		return rdev->desc->name;
79	else
80		return "";
81}
82
83/* gets the regulator for a given consumer device */
84static struct regulator *get_device_regulator(struct device *dev)
85{
86	struct regulator *regulator = NULL;
87	struct regulator_dev *rdev;
88
89	mutex_lock(&regulator_list_mutex);
90	list_for_each_entry(rdev, &regulator_list, list) {
91		mutex_lock(&rdev->mutex);
92		list_for_each_entry(regulator, &rdev->consumer_list, list) {
93			if (regulator->dev == dev) {
94				mutex_unlock(&rdev->mutex);
95				mutex_unlock(&regulator_list_mutex);
96				return regulator;
97			}
98		}
99		mutex_unlock(&rdev->mutex);
100	}
101	mutex_unlock(&regulator_list_mutex);
102	return NULL;
103}
104
105/* Platform voltage constraint check */
106static int regulator_check_voltage(struct regulator_dev *rdev,
107				   int *min_uV, int *max_uV)
108{
109	BUG_ON(*min_uV > *max_uV);
110
111	if (!rdev->constraints) {
112		printk(KERN_ERR "%s: no constraints for %s\n", __func__,
113		       rdev_get_name(rdev));
114		return -ENODEV;
115	}
116	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
117		printk(KERN_ERR "%s: operation not allowed for %s\n",
118		       __func__, rdev_get_name(rdev));
119		return -EPERM;
120	}
121
122	if (*max_uV > rdev->constraints->max_uV)
123		*max_uV = rdev->constraints->max_uV;
124	if (*min_uV < rdev->constraints->min_uV)
125		*min_uV = rdev->constraints->min_uV;
126
127	if (*min_uV > *max_uV)
128		return -EINVAL;
129
130	return 0;
131}
132
133/* current constraint check */
134static int regulator_check_current_limit(struct regulator_dev *rdev,
135					int *min_uA, int *max_uA)
136{
137	BUG_ON(*min_uA > *max_uA);
138
139	if (!rdev->constraints) {
140		printk(KERN_ERR "%s: no constraints for %s\n", __func__,
141		       rdev_get_name(rdev));
142		return -ENODEV;
143	}
144	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_CURRENT)) {
145		printk(KERN_ERR "%s: operation not allowed for %s\n",
146		       __func__, rdev_get_name(rdev));
147		return -EPERM;
148	}
149
150	if (*max_uA > rdev->constraints->max_uA)
151		*max_uA = rdev->constraints->max_uA;
152	if (*min_uA < rdev->constraints->min_uA)
153		*min_uA = rdev->constraints->min_uA;
154
155	if (*min_uA > *max_uA)
156		return -EINVAL;
157
158	return 0;
159}
160
161/* operating mode constraint check */
162static int regulator_check_mode(struct regulator_dev *rdev, int mode)
163{
164	switch (mode) {
165	case REGULATOR_MODE_FAST:
166	case REGULATOR_MODE_NORMAL:
167	case REGULATOR_MODE_IDLE:
168	case REGULATOR_MODE_STANDBY:
169		break;
170	default:
171		return -EINVAL;
172	}
173
174	if (!rdev->constraints) {
175		printk(KERN_ERR "%s: no constraints for %s\n", __func__,
176		       rdev_get_name(rdev));
177		return -ENODEV;
178	}
179	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_MODE)) {
180		printk(KERN_ERR "%s: operation not allowed for %s\n",
181		       __func__, rdev_get_name(rdev));
182		return -EPERM;
183	}
184	if (!(rdev->constraints->valid_modes_mask & mode)) {
185		printk(KERN_ERR "%s: invalid mode %x for %s\n",
186		       __func__, mode, rdev_get_name(rdev));
187		return -EINVAL;
188	}
189	return 0;
190}
191
192/* dynamic regulator mode switching constraint check */
193static int regulator_check_drms(struct regulator_dev *rdev)
194{
195	if (!rdev->constraints) {
196		printk(KERN_ERR "%s: no constraints for %s\n", __func__,
197		       rdev_get_name(rdev));
198		return -ENODEV;
199	}
200	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS)) {
201		printk(KERN_ERR "%s: operation not allowed for %s\n",
202		       __func__, rdev_get_name(rdev));
203		return -EPERM;
204	}
205	return 0;
206}
207
208static ssize_t device_requested_uA_show(struct device *dev,
209			     struct device_attribute *attr, char *buf)
210{
211	struct regulator *regulator;
212
213	regulator = get_device_regulator(dev);
214	if (regulator == NULL)
215		return 0;
216
217	return sprintf(buf, "%d\n", regulator->uA_load);
218}
219
220static ssize_t regulator_uV_show(struct device *dev,
221				struct device_attribute *attr, char *buf)
222{
223	struct regulator_dev *rdev = dev_get_drvdata(dev);
224	ssize_t ret;
225
226	mutex_lock(&rdev->mutex);
227	ret = sprintf(buf, "%d\n", _regulator_get_voltage(rdev));
228	mutex_unlock(&rdev->mutex);
229
230	return ret;
231}
232static DEVICE_ATTR(microvolts, 0444, regulator_uV_show, NULL);
233
234static ssize_t regulator_uA_show(struct device *dev,
235				struct device_attribute *attr, char *buf)
236{
237	struct regulator_dev *rdev = dev_get_drvdata(dev);
238
239	return sprintf(buf, "%d\n", _regulator_get_current_limit(rdev));
240}
241static DEVICE_ATTR(microamps, 0444, regulator_uA_show, NULL);
242
243static ssize_t regulator_name_show(struct device *dev,
244			     struct device_attribute *attr, char *buf)
245{
246	struct regulator_dev *rdev = dev_get_drvdata(dev);
247
248	return sprintf(buf, "%s\n", rdev_get_name(rdev));
249}
250
251static ssize_t regulator_print_opmode(char *buf, int mode)
252{
253	switch (mode) {
254	case REGULATOR_MODE_FAST:
255		return sprintf(buf, "fast\n");
256	case REGULATOR_MODE_NORMAL:
257		return sprintf(buf, "normal\n");
258	case REGULATOR_MODE_IDLE:
259		return sprintf(buf, "idle\n");
260	case REGULATOR_MODE_STANDBY:
261		return sprintf(buf, "standby\n");
262	}
263	return sprintf(buf, "unknown\n");
264}
265
266static ssize_t regulator_opmode_show(struct device *dev,
267				    struct device_attribute *attr, char *buf)
268{
269	struct regulator_dev *rdev = dev_get_drvdata(dev);
270
271	return regulator_print_opmode(buf, _regulator_get_mode(rdev));
272}
273static DEVICE_ATTR(opmode, 0444, regulator_opmode_show, NULL);
274
275static ssize_t regulator_print_state(char *buf, int state)
276{
277	if (state > 0)
278		return sprintf(buf, "enabled\n");
279	else if (state == 0)
280		return sprintf(buf, "disabled\n");
281	else
282		return sprintf(buf, "unknown\n");
283}
284
285static ssize_t regulator_state_show(struct device *dev,
286				   struct device_attribute *attr, char *buf)
287{
288	struct regulator_dev *rdev = dev_get_drvdata(dev);
289	ssize_t ret;
290
291	mutex_lock(&rdev->mutex);
292	ret = regulator_print_state(buf, _regulator_is_enabled(rdev));
293	mutex_unlock(&rdev->mutex);
294
295	return ret;
296}
297static DEVICE_ATTR(state, 0444, regulator_state_show, NULL);
298
299static ssize_t regulator_status_show(struct device *dev,
300				   struct device_attribute *attr, char *buf)
301{
302	struct regulator_dev *rdev = dev_get_drvdata(dev);
303	int status;
304	char *label;
305
306	status = rdev->desc->ops->get_status(rdev);
307	if (status < 0)
308		return status;
309
310	switch (status) {
311	case REGULATOR_STATUS_OFF:
312		label = "off";
313		break;
314	case REGULATOR_STATUS_ON:
315		label = "on";
316		break;
317	case REGULATOR_STATUS_ERROR:
318		label = "error";
319		break;
320	case REGULATOR_STATUS_FAST:
321		label = "fast";
322		break;
323	case REGULATOR_STATUS_NORMAL:
324		label = "normal";
325		break;
326	case REGULATOR_STATUS_IDLE:
327		label = "idle";
328		break;
329	case REGULATOR_STATUS_STANDBY:
330		label = "standby";
331		break;
332	default:
333		return -ERANGE;
334	}
335
336	return sprintf(buf, "%s\n", label);
337}
338static DEVICE_ATTR(status, 0444, regulator_status_show, NULL);
339
340static ssize_t regulator_min_uA_show(struct device *dev,
341				    struct device_attribute *attr, char *buf)
342{
343	struct regulator_dev *rdev = dev_get_drvdata(dev);
344
345	if (!rdev->constraints)
346		return sprintf(buf, "constraint not defined\n");
347
348	return sprintf(buf, "%d\n", rdev->constraints->min_uA);
349}
350static DEVICE_ATTR(min_microamps, 0444, regulator_min_uA_show, NULL);
351
352static ssize_t regulator_max_uA_show(struct device *dev,
353				    struct device_attribute *attr, char *buf)
354{
355	struct regulator_dev *rdev = dev_get_drvdata(dev);
356
357	if (!rdev->constraints)
358		return sprintf(buf, "constraint not defined\n");
359
360	return sprintf(buf, "%d\n", rdev->constraints->max_uA);
361}
362static DEVICE_ATTR(max_microamps, 0444, regulator_max_uA_show, NULL);
363
364static ssize_t regulator_min_uV_show(struct device *dev,
365				    struct device_attribute *attr, char *buf)
366{
367	struct regulator_dev *rdev = dev_get_drvdata(dev);
368
369	if (!rdev->constraints)
370		return sprintf(buf, "constraint not defined\n");
371
372	return sprintf(buf, "%d\n", rdev->constraints->min_uV);
373}
374static DEVICE_ATTR(min_microvolts, 0444, regulator_min_uV_show, NULL);
375
376static ssize_t regulator_max_uV_show(struct device *dev,
377				    struct device_attribute *attr, char *buf)
378{
379	struct regulator_dev *rdev = dev_get_drvdata(dev);
380
381	if (!rdev->constraints)
382		return sprintf(buf, "constraint not defined\n");
383
384	return sprintf(buf, "%d\n", rdev->constraints->max_uV);
385}
386static DEVICE_ATTR(max_microvolts, 0444, regulator_max_uV_show, NULL);
387
388static ssize_t regulator_total_uA_show(struct device *dev,
389				      struct device_attribute *attr, char *buf)
390{
391	struct regulator_dev *rdev = dev_get_drvdata(dev);
392	struct regulator *regulator;
393	int uA = 0;
394
395	mutex_lock(&rdev->mutex);
396	list_for_each_entry(regulator, &rdev->consumer_list, list)
397		uA += regulator->uA_load;
398	mutex_unlock(&rdev->mutex);
399	return sprintf(buf, "%d\n", uA);
400}
401static DEVICE_ATTR(requested_microamps, 0444, regulator_total_uA_show, NULL);
402
403static ssize_t regulator_num_users_show(struct device *dev,
404				      struct device_attribute *attr, char *buf)
405{
406	struct regulator_dev *rdev = dev_get_drvdata(dev);
407	return sprintf(buf, "%d\n", rdev->use_count);
408}
409
410static ssize_t regulator_type_show(struct device *dev,
411				  struct device_attribute *attr, char *buf)
412{
413	struct regulator_dev *rdev = dev_get_drvdata(dev);
414
415	switch (rdev->desc->type) {
416	case REGULATOR_VOLTAGE:
417		return sprintf(buf, "voltage\n");
418	case REGULATOR_CURRENT:
419		return sprintf(buf, "current\n");
420	}
421	return sprintf(buf, "unknown\n");
422}
423
424static ssize_t regulator_suspend_mem_uV_show(struct device *dev,
425				struct device_attribute *attr, char *buf)
426{
427	struct regulator_dev *rdev = dev_get_drvdata(dev);
428
429	return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
430}
431static DEVICE_ATTR(suspend_mem_microvolts, 0444,
432		regulator_suspend_mem_uV_show, NULL);
433
434static ssize_t regulator_suspend_disk_uV_show(struct device *dev,
435				struct device_attribute *attr, char *buf)
436{
437	struct regulator_dev *rdev = dev_get_drvdata(dev);
438
439	return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
440}
441static DEVICE_ATTR(suspend_disk_microvolts, 0444,
442		regulator_suspend_disk_uV_show, NULL);
443
444static ssize_t regulator_suspend_standby_uV_show(struct device *dev,
445				struct device_attribute *attr, char *buf)
446{
447	struct regulator_dev *rdev = dev_get_drvdata(dev);
448
449	return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
450}
451static DEVICE_ATTR(suspend_standby_microvolts, 0444,
452		regulator_suspend_standby_uV_show, NULL);
453
454static ssize_t regulator_suspend_mem_mode_show(struct device *dev,
455				struct device_attribute *attr, char *buf)
456{
457	struct regulator_dev *rdev = dev_get_drvdata(dev);
458
459	return regulator_print_opmode(buf,
460		rdev->constraints->state_mem.mode);
461}
462static DEVICE_ATTR(suspend_mem_mode, 0444,
463		regulator_suspend_mem_mode_show, NULL);
464
465static ssize_t regulator_suspend_disk_mode_show(struct device *dev,
466				struct device_attribute *attr, char *buf)
467{
468	struct regulator_dev *rdev = dev_get_drvdata(dev);
469
470	return regulator_print_opmode(buf,
471		rdev->constraints->state_disk.mode);
472}
473static DEVICE_ATTR(suspend_disk_mode, 0444,
474		regulator_suspend_disk_mode_show, NULL);
475
476static ssize_t regulator_suspend_standby_mode_show(struct device *dev,
477				struct device_attribute *attr, char *buf)
478{
479	struct regulator_dev *rdev = dev_get_drvdata(dev);
480
481	return regulator_print_opmode(buf,
482		rdev->constraints->state_standby.mode);
483}
484static DEVICE_ATTR(suspend_standby_mode, 0444,
485		regulator_suspend_standby_mode_show, NULL);
486
487static ssize_t regulator_suspend_mem_state_show(struct device *dev,
488				   struct device_attribute *attr, char *buf)
489{
490	struct regulator_dev *rdev = dev_get_drvdata(dev);
491
492	return regulator_print_state(buf,
493			rdev->constraints->state_mem.enabled);
494}
495static DEVICE_ATTR(suspend_mem_state, 0444,
496		regulator_suspend_mem_state_show, NULL);
497
498static ssize_t regulator_suspend_disk_state_show(struct device *dev,
499				   struct device_attribute *attr, char *buf)
500{
501	struct regulator_dev *rdev = dev_get_drvdata(dev);
502
503	return regulator_print_state(buf,
504			rdev->constraints->state_disk.enabled);
505}
506static DEVICE_ATTR(suspend_disk_state, 0444,
507		regulator_suspend_disk_state_show, NULL);
508
509static ssize_t regulator_suspend_standby_state_show(struct device *dev,
510				   struct device_attribute *attr, char *buf)
511{
512	struct regulator_dev *rdev = dev_get_drvdata(dev);
513
514	return regulator_print_state(buf,
515			rdev->constraints->state_standby.enabled);
516}
517static DEVICE_ATTR(suspend_standby_state, 0444,
518		regulator_suspend_standby_state_show, NULL);
519
520
521/*
522 * These are the only attributes are present for all regulators.
523 * Other attributes are a function of regulator functionality.
524 */
525static struct device_attribute regulator_dev_attrs[] = {
526	__ATTR(name, 0444, regulator_name_show, NULL),
527	__ATTR(num_users, 0444, regulator_num_users_show, NULL),
528	__ATTR(type, 0444, regulator_type_show, NULL),
529	__ATTR_NULL,
530};
531
532static void regulator_dev_release(struct device *dev)
533{
534	struct regulator_dev *rdev = dev_get_drvdata(dev);
535	kfree(rdev);
536}
537
538static struct class regulator_class = {
539	.name = "regulator",
540	.dev_release = regulator_dev_release,
541	.dev_attrs = regulator_dev_attrs,
542};
543
544/* Calculate the new optimum regulator operating mode based on the new total
545 * consumer load. All locks held by caller */
546static void drms_uA_update(struct regulator_dev *rdev)
547{
548	struct regulator *sibling;
549	int current_uA = 0, output_uV, input_uV, err;
550	unsigned int mode;
551
552	err = regulator_check_drms(rdev);
553	if (err < 0 || !rdev->desc->ops->get_optimum_mode ||
554	    !rdev->desc->ops->get_voltage || !rdev->desc->ops->set_mode)
555		return;
556
557	/* get output voltage */
558	output_uV = rdev->desc->ops->get_voltage(rdev);
559	if (output_uV <= 0)
560		return;
561
562	/* get input voltage */
563	if (rdev->supply && rdev->supply->desc->ops->get_voltage)
564		input_uV = rdev->supply->desc->ops->get_voltage(rdev->supply);
565	else
566		input_uV = rdev->constraints->input_uV;
567	if (input_uV <= 0)
568		return;
569
570	/* calc total requested load */
571	list_for_each_entry(sibling, &rdev->consumer_list, list)
572		current_uA += sibling->uA_load;
573
574	/* now get the optimum mode for our new total regulator load */
575	mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
576						  output_uV, current_uA);
577
578	/* check the new mode is allowed */
579	err = regulator_check_mode(rdev, mode);
580	if (err == 0)
581		rdev->desc->ops->set_mode(rdev, mode);
582}
583
584static int suspend_set_state(struct regulator_dev *rdev,
585	struct regulator_state *rstate)
586{
587	int ret = 0;
588	bool can_set_state;
589
590	can_set_state = rdev->desc->ops->set_suspend_enable &&
591		rdev->desc->ops->set_suspend_disable;
592
593	/* If we have no suspend mode configration don't set anything;
594	 * only warn if the driver actually makes the suspend mode
595	 * configurable.
596	 */
597	if (!rstate->enabled && !rstate->disabled) {
598		if (can_set_state)
599			printk(KERN_WARNING "%s: No configuration for %s\n",
600			       __func__, rdev_get_name(rdev));
601		return 0;
602	}
603
604	if (rstate->enabled && rstate->disabled) {
605		printk(KERN_ERR "%s: invalid configuration for %s\n",
606		       __func__, rdev_get_name(rdev));
607		return -EINVAL;
608	}
609
610	if (!can_set_state) {
611		printk(KERN_ERR "%s: no way to set suspend state\n",
612			__func__);
613		return -EINVAL;
614	}
615
616	if (rstate->enabled)
617		ret = rdev->desc->ops->set_suspend_enable(rdev);
618	else
619		ret = rdev->desc->ops->set_suspend_disable(rdev);
620	if (ret < 0) {
621		printk(KERN_ERR "%s: failed to enabled/disable\n", __func__);
622		return ret;
623	}
624
625	if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
626		ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
627		if (ret < 0) {
628			printk(KERN_ERR "%s: failed to set voltage\n",
629				__func__);
630			return ret;
631		}
632	}
633
634	if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
635		ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
636		if (ret < 0) {
637			printk(KERN_ERR "%s: failed to set mode\n", __func__);
638			return ret;
639		}
640	}
641	return ret;
642}
643
644/* locks held by caller */
645static int suspend_prepare(struct regulator_dev *rdev, suspend_state_t state)
646{
647	if (!rdev->constraints)
648		return -EINVAL;
649
650	switch (state) {
651	case PM_SUSPEND_STANDBY:
652		return suspend_set_state(rdev,
653			&rdev->constraints->state_standby);
654	case PM_SUSPEND_MEM:
655		return suspend_set_state(rdev,
656			&rdev->constraints->state_mem);
657	case PM_SUSPEND_MAX:
658		return suspend_set_state(rdev,
659			&rdev->constraints->state_disk);
660	default:
661		return -EINVAL;
662	}
663}
664
665static void print_constraints(struct regulator_dev *rdev)
666{
667	struct regulation_constraints *constraints = rdev->constraints;
668	char buf[80] = "";
669	int count = 0;
670	int ret;
671
672	if (constraints->min_uV && constraints->max_uV) {
673		if (constraints->min_uV == constraints->max_uV)
674			count += sprintf(buf + count, "%d mV ",
675					 constraints->min_uV / 1000);
676		else
677			count += sprintf(buf + count, "%d <--> %d mV ",
678					 constraints->min_uV / 1000,
679					 constraints->max_uV / 1000);
680	}
681
682	if (!constraints->min_uV ||
683	    constraints->min_uV != constraints->max_uV) {
684		ret = _regulator_get_voltage(rdev);
685		if (ret > 0)
686			count += sprintf(buf + count, "at %d mV ", ret / 1000);
687	}
688
689	if (constraints->min_uA && constraints->max_uA) {
690		if (constraints->min_uA == constraints->max_uA)
691			count += sprintf(buf + count, "%d mA ",
692					 constraints->min_uA / 1000);
693		else
694			count += sprintf(buf + count, "%d <--> %d mA ",
695					 constraints->min_uA / 1000,
696					 constraints->max_uA / 1000);
697	}
698
699	if (!constraints->min_uA ||
700	    constraints->min_uA != constraints->max_uA) {
701		ret = _regulator_get_current_limit(rdev);
702		if (ret > 0)
703			count += sprintf(buf + count, "at %d uA ", ret / 1000);
704	}
705
706	if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
707		count += sprintf(buf + count, "fast ");
708	if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
709		count += sprintf(buf + count, "normal ");
710	if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
711		count += sprintf(buf + count, "idle ");
712	if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
713		count += sprintf(buf + count, "standby");
714
715	printk(KERN_INFO "regulator: %s: %s\n", rdev_get_name(rdev), buf);
716}
717
718static int machine_constraints_voltage(struct regulator_dev *rdev,
719	struct regulation_constraints *constraints)
720{
721	struct regulator_ops *ops = rdev->desc->ops;
722	const char *name = rdev_get_name(rdev);
723	int ret;
724
725	/* do we need to apply the constraint voltage */
726	if (rdev->constraints->apply_uV &&
727		rdev->constraints->min_uV == rdev->constraints->max_uV &&
728		ops->set_voltage) {
729		ret = ops->set_voltage(rdev,
730			rdev->constraints->min_uV, rdev->constraints->max_uV);
731			if (ret < 0) {
732				printk(KERN_ERR "%s: failed to apply %duV constraint to %s\n",
733				       __func__,
734				       rdev->constraints->min_uV, name);
735				rdev->constraints = NULL;
736				return ret;
737			}
738	}
739
740	/* constrain machine-level voltage specs to fit
741	 * the actual range supported by this regulator.
742	 */
743	if (ops->list_voltage && rdev->desc->n_voltages) {
744		int	count = rdev->desc->n_voltages;
745		int	i;
746		int	min_uV = INT_MAX;
747		int	max_uV = INT_MIN;
748		int	cmin = constraints->min_uV;
749		int	cmax = constraints->max_uV;
750
751		/* it's safe to autoconfigure fixed-voltage supplies
752		   and the constraints are used by list_voltage. */
753		if (count == 1 && !cmin) {
754			cmin = 1;
755			cmax = INT_MAX;
756			constraints->min_uV = cmin;
757			constraints->max_uV = cmax;
758		}
759
760		/* voltage constraints are optional */
761		if ((cmin == 0) && (cmax == 0))
762			return 0;
763
764		/* else require explicit machine-level constraints */
765		if (cmin <= 0 || cmax <= 0 || cmax < cmin) {
766			pr_err("%s: %s '%s' voltage constraints\n",
767				       __func__, "invalid", name);
768			return -EINVAL;
769		}
770
771		/* initial: [cmin..cmax] valid, [min_uV..max_uV] not */
772		for (i = 0; i < count; i++) {
773			int	value;
774
775			value = ops->list_voltage(rdev, i);
776			if (value <= 0)
777				continue;
778
779			/* maybe adjust [min_uV..max_uV] */
780			if (value >= cmin && value < min_uV)
781				min_uV = value;
782			if (value <= cmax && value > max_uV)
783				max_uV = value;
784		}
785
786		/* final: [min_uV..max_uV] valid iff constraints valid */
787		if (max_uV < min_uV) {
788			pr_err("%s: %s '%s' voltage constraints\n",
789				       __func__, "unsupportable", name);
790			return -EINVAL;
791		}
792
793		/* use regulator's subset of machine constraints */
794		if (constraints->min_uV < min_uV) {
795			pr_debug("%s: override '%s' %s, %d -> %d\n",
796				       __func__, name, "min_uV",
797					constraints->min_uV, min_uV);
798			constraints->min_uV = min_uV;
799		}
800		if (constraints->max_uV > max_uV) {
801			pr_debug("%s: override '%s' %s, %d -> %d\n",
802				       __func__, name, "max_uV",
803					constraints->max_uV, max_uV);
804			constraints->max_uV = max_uV;
805		}
806	}
807
808	return 0;
809}
810
811/**
812 * set_machine_constraints - sets regulator constraints
813 * @rdev: regulator source
814 * @constraints: constraints to apply
815 *
816 * Allows platform initialisation code to define and constrain
817 * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
818 * Constraints *must* be set by platform code in order for some
819 * regulator operations to proceed i.e. set_voltage, set_current_limit,
820 * set_mode.
821 */
822static int set_machine_constraints(struct regulator_dev *rdev,
823	struct regulation_constraints *constraints)
824{
825	int ret = 0;
826	const char *name;
827	struct regulator_ops *ops = rdev->desc->ops;
828
829	rdev->constraints = constraints;
830
831	name = rdev_get_name(rdev);
832
833	ret = machine_constraints_voltage(rdev, constraints);
834	if (ret != 0)
835		goto out;
836
837	/* do we need to setup our suspend state */
838	if (constraints->initial_state) {
839		ret = suspend_prepare(rdev, constraints->initial_state);
840		if (ret < 0) {
841			printk(KERN_ERR "%s: failed to set suspend state for %s\n",
842			       __func__, name);
843			rdev->constraints = NULL;
844			goto out;
845		}
846	}
847
848	if (constraints->initial_mode) {
849		if (!ops->set_mode) {
850			printk(KERN_ERR "%s: no set_mode operation for %s\n",
851			       __func__, name);
852			ret = -EINVAL;
853			goto out;
854		}
855
856		ret = ops->set_mode(rdev, constraints->initial_mode);
857		if (ret < 0) {
858			printk(KERN_ERR
859			       "%s: failed to set initial mode for %s: %d\n",
860			       __func__, name, ret);
861			goto out;
862		}
863	}
864
865	/* If the constraints say the regulator should be on at this point
866	 * and we have control then make sure it is enabled.
867	 */
868	if ((constraints->always_on || constraints->boot_on) && ops->enable) {
869		ret = ops->enable(rdev);
870		if (ret < 0) {
871			printk(KERN_ERR "%s: failed to enable %s\n",
872			       __func__, name);
873			rdev->constraints = NULL;
874			goto out;
875		}
876	}
877
878	print_constraints(rdev);
879out:
880	return ret;
881}
882
883/**
884 * set_supply - set regulator supply regulator
885 * @rdev: regulator name
886 * @supply_rdev: supply regulator name
887 *
888 * Called by platform initialisation code to set the supply regulator for this
889 * regulator. This ensures that a regulators supply will also be enabled by the
890 * core if it's child is enabled.
891 */
892static int set_supply(struct regulator_dev *rdev,
893	struct regulator_dev *supply_rdev)
894{
895	int err;
896
897	err = sysfs_create_link(&rdev->dev.kobj, &supply_rdev->dev.kobj,
898				"supply");
899	if (err) {
900		printk(KERN_ERR
901		       "%s: could not add device link %s err %d\n",
902		       __func__, supply_rdev->dev.kobj.name, err);
903		       goto out;
904	}
905	rdev->supply = supply_rdev;
906	list_add(&rdev->slist, &supply_rdev->supply_list);
907out:
908	return err;
909}
910
911/**
912 * set_consumer_device_supply: Bind a regulator to a symbolic supply
913 * @rdev:         regulator source
914 * @consumer_dev: device the supply applies to
915 * @consumer_dev_name: dev_name() string for device supply applies to
916 * @supply:       symbolic name for supply
917 *
918 * Allows platform initialisation code to map physical regulator
919 * sources to symbolic names for supplies for use by devices.  Devices
920 * should use these symbolic names to request regulators, avoiding the
921 * need to provide board-specific regulator names as platform data.
922 *
923 * Only one of consumer_dev and consumer_dev_name may be specified.
924 */
925static int set_consumer_device_supply(struct regulator_dev *rdev,
926	struct device *consumer_dev, const char *consumer_dev_name,
927	const char *supply)
928{
929	struct regulator_map *node;
930	int has_dev;
931
932	if (consumer_dev && consumer_dev_name)
933		return -EINVAL;
934
935	if (!consumer_dev_name && consumer_dev)
936		consumer_dev_name = dev_name(consumer_dev);
937
938	if (supply == NULL)
939		return -EINVAL;
940
941	if (consumer_dev_name != NULL)
942		has_dev = 1;
943	else
944		has_dev = 0;
945
946	list_for_each_entry(node, &regulator_map_list, list) {
947		if (node->dev_name && consumer_dev_name) {
948			if (strcmp(node->dev_name, consumer_dev_name) != 0)
949				continue;
950		} else if (node->dev_name || consumer_dev_name) {
951			continue;
952		}
953
954		if (strcmp(node->supply, supply) != 0)
955			continue;
956
957		dev_dbg(consumer_dev, "%s/%s is '%s' supply; fail %s/%s\n",
958				dev_name(&node->regulator->dev),
959				node->regulator->desc->name,
960				supply,
961				dev_name(&rdev->dev), rdev_get_name(rdev));
962		return -EBUSY;
963	}
964
965	node = kzalloc(sizeof(struct regulator_map), GFP_KERNEL);
966	if (node == NULL)
967		return -ENOMEM;
968
969	node->regulator = rdev;
970	node->supply = supply;
971
972	if (has_dev) {
973		node->dev_name = kstrdup(consumer_dev_name, GFP_KERNEL);
974		if (node->dev_name == NULL) {
975			kfree(node);
976			return -ENOMEM;
977		}
978	}
979
980	list_add(&node->list, &regulator_map_list);
981	return 0;
982}
983
984static void unset_regulator_supplies(struct regulator_dev *rdev)
985{
986	struct regulator_map *node, *n;
987
988	list_for_each_entry_safe(node, n, &regulator_map_list, list) {
989		if (rdev == node->regulator) {
990			list_del(&node->list);
991			kfree(node->dev_name);
992			kfree(node);
993		}
994	}
995}
996
997#define REG_STR_SIZE	32
998
999static struct regulator *create_regulator(struct regulator_dev *rdev,
1000					  struct device *dev,
1001					  const char *supply_name)
1002{
1003	struct regulator *regulator;
1004	char buf[REG_STR_SIZE];
1005	int err, size;
1006
1007	regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
1008	if (regulator == NULL)
1009		return NULL;
1010
1011	mutex_lock(&rdev->mutex);
1012	regulator->rdev = rdev;
1013	list_add(&regulator->list, &rdev->consumer_list);
1014
1015	if (dev) {
1016		/* create a 'requested_microamps_name' sysfs entry */
1017		size = scnprintf(buf, REG_STR_SIZE, "microamps_requested_%s",
1018			supply_name);
1019		if (size >= REG_STR_SIZE)
1020			goto overflow_err;
1021
1022		regulator->dev = dev;
1023		sysfs_attr_init(&regulator->dev_attr.attr);
1024		regulator->dev_attr.attr.name = kstrdup(buf, GFP_KERNEL);
1025		if (regulator->dev_attr.attr.name == NULL)
1026			goto attr_name_err;
1027
1028		regulator->dev_attr.attr.mode = 0444;
1029		regulator->dev_attr.show = device_requested_uA_show;
1030		err = device_create_file(dev, &regulator->dev_attr);
1031		if (err < 0) {
1032			printk(KERN_WARNING "%s: could not add regulator_dev"
1033				" load sysfs\n", __func__);
1034			goto attr_name_err;
1035		}
1036
1037		/* also add a link to the device sysfs entry */
1038		size = scnprintf(buf, REG_STR_SIZE, "%s-%s",
1039				 dev->kobj.name, supply_name);
1040		if (size >= REG_STR_SIZE)
1041			goto attr_err;
1042
1043		regulator->supply_name = kstrdup(buf, GFP_KERNEL);
1044		if (regulator->supply_name == NULL)
1045			goto attr_err;
1046
1047		err = sysfs_create_link(&rdev->dev.kobj, &dev->kobj,
1048					buf);
1049		if (err) {
1050			printk(KERN_WARNING
1051			       "%s: could not add device link %s err %d\n",
1052			       __func__, dev->kobj.name, err);
1053			device_remove_file(dev, &regulator->dev_attr);
1054			goto link_name_err;
1055		}
1056	}
1057	mutex_unlock(&rdev->mutex);
1058	return regulator;
1059link_name_err:
1060	kfree(regulator->supply_name);
1061attr_err:
1062	device_remove_file(regulator->dev, &regulator->dev_attr);
1063attr_name_err:
1064	kfree(regulator->dev_attr.attr.name);
1065overflow_err:
1066	list_del(&regulator->list);
1067	kfree(regulator);
1068	mutex_unlock(&rdev->mutex);
1069	return NULL;
1070}
1071
1072static int _regulator_get_enable_time(struct regulator_dev *rdev)
1073{
1074	if (!rdev->desc->ops->enable_time)
1075		return 0;
1076	return rdev->desc->ops->enable_time(rdev);
1077}
1078
1079/* Internal regulator request function */
1080static struct regulator *_regulator_get(struct device *dev, const char *id,
1081					int exclusive)
1082{
1083	struct regulator_dev *rdev;
1084	struct regulator_map *map;
1085	struct regulator *regulator = ERR_PTR(-ENODEV);
1086	const char *devname = NULL;
1087	int ret;
1088
1089	if (id == NULL) {
1090		printk(KERN_ERR "regulator: get() with no identifier\n");
1091		return regulator;
1092	}
1093
1094	if (dev)
1095		devname = dev_name(dev);
1096
1097	mutex_lock(&regulator_list_mutex);
1098
1099	list_for_each_entry(map, &regulator_map_list, list) {
1100		/* If the mapping has a device set up it must match */
1101		if (map->dev_name &&
1102		    (!devname || strcmp(map->dev_name, devname)))
1103			continue;
1104
1105		if (strcmp(map->supply, id) == 0) {
1106			rdev = map->regulator;
1107			goto found;
1108		}
1109	}
1110
1111#ifdef CONFIG_REGULATOR_DUMMY
1112	if (!devname)
1113		devname = "deviceless";
1114
1115	/* If the board didn't flag that it was fully constrained then
1116	 * substitute in a dummy regulator so consumers can continue.
1117	 */
1118	if (!has_full_constraints) {
1119		pr_warning("%s supply %s not found, using dummy regulator\n",
1120			   devname, id);
1121		rdev = dummy_regulator_rdev;
1122		goto found;
1123	}
1124#endif
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	/* If we don't know then assume that the regulator is always on */
1470	if (!rdev->desc->ops->is_enabled)
1471		return 1;
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 system, 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	int regulator_curr_mode;
1748
1749	mutex_lock(&rdev->mutex);
1750
1751	/* sanity check */
1752	if (!rdev->desc->ops->set_mode) {
1753		ret = -EINVAL;
1754		goto out;
1755	}
1756
1757	/* return if the same mode is requested */
1758	if (rdev->desc->ops->get_mode) {
1759		regulator_curr_mode = rdev->desc->ops->get_mode(rdev);
1760		if (regulator_curr_mode == mode) {
1761			ret = 0;
1762			goto out;
1763		}
1764	}
1765
1766	/* constraints check */
1767	ret = regulator_check_mode(rdev, mode);
1768	if (ret < 0)
1769		goto out;
1770
1771	ret = rdev->desc->ops->set_mode(rdev, mode);
1772out:
1773	mutex_unlock(&rdev->mutex);
1774	return ret;
1775}
1776EXPORT_SYMBOL_GPL(regulator_set_mode);
1777
1778static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
1779{
1780	int ret;
1781
1782	mutex_lock(&rdev->mutex);
1783
1784	/* sanity check */
1785	if (!rdev->desc->ops->get_mode) {
1786		ret = -EINVAL;
1787		goto out;
1788	}
1789
1790	ret = rdev->desc->ops->get_mode(rdev);
1791out:
1792	mutex_unlock(&rdev->mutex);
1793	return ret;
1794}
1795
1796/**
1797 * regulator_get_mode - get regulator operating mode
1798 * @regulator: regulator source
1799 *
1800 * Get the current regulator operating mode.
1801 */
1802unsigned int regulator_get_mode(struct regulator *regulator)
1803{
1804	return _regulator_get_mode(regulator->rdev);
1805}
1806EXPORT_SYMBOL_GPL(regulator_get_mode);
1807
1808/**
1809 * regulator_set_optimum_mode - set regulator optimum operating mode
1810 * @regulator: regulator source
1811 * @uA_load: load current
1812 *
1813 * Notifies the regulator core of a new device load. This is then used by
1814 * DRMS (if enabled by constraints) to set the most efficient regulator
1815 * operating mode for the new regulator loading.
1816 *
1817 * Consumer devices notify their supply regulator of the maximum power
1818 * they will require (can be taken from device datasheet in the power
1819 * consumption tables) when they change operational status and hence power
1820 * state. Examples of operational state changes that can affect power
1821 * consumption are :-
1822 *
1823 *    o Device is opened / closed.
1824 *    o Device I/O is about to begin or has just finished.
1825 *    o Device is idling in between work.
1826 *
1827 * This information is also exported via sysfs to userspace.
1828 *
1829 * DRMS will sum the total requested load on the regulator and change
1830 * to the most efficient operating mode if platform constraints allow.
1831 *
1832 * Returns the new regulator mode or error.
1833 */
1834int regulator_set_optimum_mode(struct regulator *regulator, int uA_load)
1835{
1836	struct regulator_dev *rdev = regulator->rdev;
1837	struct regulator *consumer;
1838	int ret, output_uV, input_uV, total_uA_load = 0;
1839	unsigned int mode;
1840
1841	mutex_lock(&rdev->mutex);
1842
1843	regulator->uA_load = uA_load;
1844	ret = regulator_check_drms(rdev);
1845	if (ret < 0)
1846		goto out;
1847	ret = -EINVAL;
1848
1849	/* sanity check */
1850	if (!rdev->desc->ops->get_optimum_mode)
1851		goto out;
1852
1853	/* get output voltage */
1854	output_uV = rdev->desc->ops->get_voltage(rdev);
1855	if (output_uV <= 0) {
1856		printk(KERN_ERR "%s: invalid output voltage found for %s\n",
1857			__func__, rdev_get_name(rdev));
1858		goto out;
1859	}
1860
1861	/* get input voltage */
1862	if (rdev->supply && rdev->supply->desc->ops->get_voltage)
1863		input_uV = rdev->supply->desc->ops->get_voltage(rdev->supply);
1864	else
1865		input_uV = rdev->constraints->input_uV;
1866	if (input_uV <= 0) {
1867		printk(KERN_ERR "%s: invalid input voltage found for %s\n",
1868			__func__, rdev_get_name(rdev));
1869		goto out;
1870	}
1871
1872	/* calc total requested load for this regulator */
1873	list_for_each_entry(consumer, &rdev->consumer_list, list)
1874		total_uA_load += consumer->uA_load;
1875
1876	mode = rdev->desc->ops->get_optimum_mode(rdev,
1877						 input_uV, output_uV,
1878						 total_uA_load);
1879	ret = regulator_check_mode(rdev, mode);
1880	if (ret < 0) {
1881		printk(KERN_ERR "%s: failed to get optimum mode for %s @"
1882			" %d uA %d -> %d uV\n", __func__, rdev_get_name(rdev),
1883			total_uA_load, input_uV, output_uV);
1884		goto out;
1885	}
1886
1887	ret = rdev->desc->ops->set_mode(rdev, mode);
1888	if (ret < 0) {
1889		printk(KERN_ERR "%s: failed to set optimum mode %x for %s\n",
1890			__func__, mode, rdev_get_name(rdev));
1891		goto out;
1892	}
1893	ret = mode;
1894out:
1895	mutex_unlock(&rdev->mutex);
1896	return ret;
1897}
1898EXPORT_SYMBOL_GPL(regulator_set_optimum_mode);
1899
1900/**
1901 * regulator_register_notifier - register regulator event notifier
1902 * @regulator: regulator source
1903 * @nb: notifier block
1904 *
1905 * Register notifier block to receive regulator events.
1906 */
1907int regulator_register_notifier(struct regulator *regulator,
1908			      struct notifier_block *nb)
1909{
1910	return blocking_notifier_chain_register(&regulator->rdev->notifier,
1911						nb);
1912}
1913EXPORT_SYMBOL_GPL(regulator_register_notifier);
1914
1915/**
1916 * regulator_unregister_notifier - unregister regulator event notifier
1917 * @regulator: regulator source
1918 * @nb: notifier block
1919 *
1920 * Unregister regulator event notifier block.
1921 */
1922int regulator_unregister_notifier(struct regulator *regulator,
1923				struct notifier_block *nb)
1924{
1925	return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
1926						  nb);
1927}
1928EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
1929
1930/* notify regulator consumers and downstream regulator consumers.
1931 * Note mutex must be held by caller.
1932 */
1933static void _notifier_call_chain(struct regulator_dev *rdev,
1934				  unsigned long event, void *data)
1935{
1936	struct regulator_dev *_rdev;
1937
1938	/* call rdev chain first */
1939	blocking_notifier_call_chain(&rdev->notifier, event, NULL);
1940
1941	/* now notify regulator we supply */
1942	list_for_each_entry(_rdev, &rdev->supply_list, slist) {
1943		mutex_lock(&_rdev->mutex);
1944		_notifier_call_chain(_rdev, event, data);
1945		mutex_unlock(&_rdev->mutex);
1946	}
1947}
1948
1949/**
1950 * regulator_bulk_get - get multiple regulator consumers
1951 *
1952 * @dev:           Device to supply
1953 * @num_consumers: Number of consumers to register
1954 * @consumers:     Configuration of consumers; clients are stored here.
1955 *
1956 * @return 0 on success, an errno on failure.
1957 *
1958 * This helper function allows drivers to get several regulator
1959 * consumers in one operation.  If any of the regulators cannot be
1960 * acquired then any regulators that were allocated will be freed
1961 * before returning to the caller.
1962 */
1963int regulator_bulk_get(struct device *dev, int num_consumers,
1964		       struct regulator_bulk_data *consumers)
1965{
1966	int i;
1967	int ret;
1968
1969	for (i = 0; i < num_consumers; i++)
1970		consumers[i].consumer = NULL;
1971
1972	for (i = 0; i < num_consumers; i++) {
1973		consumers[i].consumer = regulator_get(dev,
1974						      consumers[i].supply);
1975		if (IS_ERR(consumers[i].consumer)) {
1976			ret = PTR_ERR(consumers[i].consumer);
1977			dev_err(dev, "Failed to get supply '%s': %d\n",
1978				consumers[i].supply, ret);
1979			consumers[i].consumer = NULL;
1980			goto err;
1981		}
1982	}
1983
1984	return 0;
1985
1986err:
1987	for (i = 0; i < num_consumers && consumers[i].consumer; i++)
1988		regulator_put(consumers[i].consumer);
1989
1990	return ret;
1991}
1992EXPORT_SYMBOL_GPL(regulator_bulk_get);
1993
1994/**
1995 * regulator_bulk_enable - enable multiple regulator consumers
1996 *
1997 * @num_consumers: Number of consumers
1998 * @consumers:     Consumer data; clients are stored here.
1999 * @return         0 on success, an errno on failure
2000 *
2001 * This convenience API allows consumers to enable multiple regulator
2002 * clients in a single API call.  If any consumers cannot be enabled
2003 * then any others that were enabled will be disabled again prior to
2004 * return.
2005 */
2006int regulator_bulk_enable(int num_consumers,
2007			  struct regulator_bulk_data *consumers)
2008{
2009	int i;
2010	int ret;
2011
2012	for (i = 0; i < num_consumers; i++) {
2013		ret = regulator_enable(consumers[i].consumer);
2014		if (ret != 0)
2015			goto err;
2016	}
2017
2018	return 0;
2019
2020err:
2021	printk(KERN_ERR "Failed to enable %s: %d\n", consumers[i].supply, ret);
2022	for (--i; i >= 0; --i)
2023		regulator_disable(consumers[i].consumer);
2024
2025	return ret;
2026}
2027EXPORT_SYMBOL_GPL(regulator_bulk_enable);
2028
2029/**
2030 * regulator_bulk_disable - disable multiple regulator consumers
2031 *
2032 * @num_consumers: Number of consumers
2033 * @consumers:     Consumer data; clients are stored here.
2034 * @return         0 on success, an errno on failure
2035 *
2036 * This convenience API allows consumers to disable multiple regulator
2037 * clients in a single API call.  If any consumers cannot be enabled
2038 * then any others that were disabled will be disabled again prior to
2039 * return.
2040 */
2041int regulator_bulk_disable(int num_consumers,
2042			   struct regulator_bulk_data *consumers)
2043{
2044	int i;
2045	int ret;
2046
2047	for (i = 0; i < num_consumers; i++) {
2048		ret = regulator_disable(consumers[i].consumer);
2049		if (ret != 0)
2050			goto err;
2051	}
2052
2053	return 0;
2054
2055err:
2056	printk(KERN_ERR "Failed to disable %s: %d\n", consumers[i].supply,
2057	       ret);
2058	for (--i; i >= 0; --i)
2059		regulator_enable(consumers[i].consumer);
2060
2061	return ret;
2062}
2063EXPORT_SYMBOL_GPL(regulator_bulk_disable);
2064
2065/**
2066 * regulator_bulk_free - free multiple regulator consumers
2067 *
2068 * @num_consumers: Number of consumers
2069 * @consumers:     Consumer data; clients are stored here.
2070 *
2071 * This convenience API allows consumers to free multiple regulator
2072 * clients in a single API call.
2073 */
2074void regulator_bulk_free(int num_consumers,
2075			 struct regulator_bulk_data *consumers)
2076{
2077	int i;
2078
2079	for (i = 0; i < num_consumers; i++) {
2080		regulator_put(consumers[i].consumer);
2081		consumers[i].consumer = NULL;
2082	}
2083}
2084EXPORT_SYMBOL_GPL(regulator_bulk_free);
2085
2086/**
2087 * regulator_notifier_call_chain - call regulator event notifier
2088 * @rdev: regulator source
2089 * @event: notifier block
2090 * @data: callback-specific data.
2091 *
2092 * Called by regulator drivers to notify clients a regulator event has
2093 * occurred. We also notify regulator clients downstream.
2094 * Note lock must be held by caller.
2095 */
2096int regulator_notifier_call_chain(struct regulator_dev *rdev,
2097				  unsigned long event, void *data)
2098{
2099	_notifier_call_chain(rdev, event, data);
2100	return NOTIFY_DONE;
2101
2102}
2103EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
2104
2105/**
2106 * regulator_mode_to_status - convert a regulator mode into a status
2107 *
2108 * @mode: Mode to convert
2109 *
2110 * Convert a regulator mode into a status.
2111 */
2112int regulator_mode_to_status(unsigned int mode)
2113{
2114	switch (mode) {
2115	case REGULATOR_MODE_FAST:
2116		return REGULATOR_STATUS_FAST;
2117	case REGULATOR_MODE_NORMAL:
2118		return REGULATOR_STATUS_NORMAL;
2119	case REGULATOR_MODE_IDLE:
2120		return REGULATOR_STATUS_IDLE;
2121	case REGULATOR_STATUS_STANDBY:
2122		return REGULATOR_STATUS_STANDBY;
2123	default:
2124		return 0;
2125	}
2126}
2127EXPORT_SYMBOL_GPL(regulator_mode_to_status);
2128
2129/*
2130 * To avoid cluttering sysfs (and memory) with useless state, only
2131 * create attributes that can be meaningfully displayed.
2132 */
2133static int add_regulator_attributes(struct regulator_dev *rdev)
2134{
2135	struct device		*dev = &rdev->dev;
2136	struct regulator_ops	*ops = rdev->desc->ops;
2137	int			status = 0;
2138
2139	/* some attributes need specific methods to be displayed */
2140	if (ops->get_voltage) {
2141		status = device_create_file(dev, &dev_attr_microvolts);
2142		if (status < 0)
2143			return status;
2144	}
2145	if (ops->get_current_limit) {
2146		status = device_create_file(dev, &dev_attr_microamps);
2147		if (status < 0)
2148			return status;
2149	}
2150	if (ops->get_mode) {
2151		status = device_create_file(dev, &dev_attr_opmode);
2152		if (status < 0)
2153			return status;
2154	}
2155	if (ops->is_enabled) {
2156		status = device_create_file(dev, &dev_attr_state);
2157		if (status < 0)
2158			return status;
2159	}
2160	if (ops->get_status) {
2161		status = device_create_file(dev, &dev_attr_status);
2162		if (status < 0)
2163			return status;
2164	}
2165
2166	/* some attributes are type-specific */
2167	if (rdev->desc->type == REGULATOR_CURRENT) {
2168		status = device_create_file(dev, &dev_attr_requested_microamps);
2169		if (status < 0)
2170			return status;
2171	}
2172
2173	/* all the other attributes exist to support constraints;
2174	 * don't show them if there are no constraints, or if the
2175	 * relevant supporting methods are missing.
2176	 */
2177	if (!rdev->constraints)
2178		return status;
2179
2180	/* constraints need specific supporting methods */
2181	if (ops->set_voltage) {
2182		status = device_create_file(dev, &dev_attr_min_microvolts);
2183		if (status < 0)
2184			return status;
2185		status = device_create_file(dev, &dev_attr_max_microvolts);
2186		if (status < 0)
2187			return status;
2188	}
2189	if (ops->set_current_limit) {
2190		status = device_create_file(dev, &dev_attr_min_microamps);
2191		if (status < 0)
2192			return status;
2193		status = device_create_file(dev, &dev_attr_max_microamps);
2194		if (status < 0)
2195			return status;
2196	}
2197
2198	/* suspend mode constraints need multiple supporting methods */
2199	if (!(ops->set_suspend_enable && ops->set_suspend_disable))
2200		return status;
2201
2202	status = device_create_file(dev, &dev_attr_suspend_standby_state);
2203	if (status < 0)
2204		return status;
2205	status = device_create_file(dev, &dev_attr_suspend_mem_state);
2206	if (status < 0)
2207		return status;
2208	status = device_create_file(dev, &dev_attr_suspend_disk_state);
2209	if (status < 0)
2210		return status;
2211
2212	if (ops->set_suspend_voltage) {
2213		status = device_create_file(dev,
2214				&dev_attr_suspend_standby_microvolts);
2215		if (status < 0)
2216			return status;
2217		status = device_create_file(dev,
2218				&dev_attr_suspend_mem_microvolts);
2219		if (status < 0)
2220			return status;
2221		status = device_create_file(dev,
2222				&dev_attr_suspend_disk_microvolts);
2223		if (status < 0)
2224			return status;
2225	}
2226
2227	if (ops->set_suspend_mode) {
2228		status = device_create_file(dev,
2229				&dev_attr_suspend_standby_mode);
2230		if (status < 0)
2231			return status;
2232		status = device_create_file(dev,
2233				&dev_attr_suspend_mem_mode);
2234		if (status < 0)
2235			return status;
2236		status = device_create_file(dev,
2237				&dev_attr_suspend_disk_mode);
2238		if (status < 0)
2239			return status;
2240	}
2241
2242	return status;
2243}
2244
2245/**
2246 * regulator_register - register regulator
2247 * @regulator_desc: regulator to register
2248 * @dev: struct device for the regulator
2249 * @init_data: platform provided init data, passed through by driver
2250 * @driver_data: private regulator data
2251 *
2252 * Called by regulator drivers to register a regulator.
2253 * Returns 0 on success.
2254 */
2255struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc,
2256	struct device *dev, struct regulator_init_data *init_data,
2257	void *driver_data)
2258{
2259	static atomic_t regulator_no = ATOMIC_INIT(0);
2260	struct regulator_dev *rdev;
2261	int ret, i;
2262
2263	if (regulator_desc == NULL)
2264		return ERR_PTR(-EINVAL);
2265
2266	if (regulator_desc->name == NULL || regulator_desc->ops == NULL)
2267		return ERR_PTR(-EINVAL);
2268
2269	if (regulator_desc->type != REGULATOR_VOLTAGE &&
2270	    regulator_desc->type != REGULATOR_CURRENT)
2271		return ERR_PTR(-EINVAL);
2272
2273	if (!init_data)
2274		return ERR_PTR(-EINVAL);
2275
2276	rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
2277	if (rdev == NULL)
2278		return ERR_PTR(-ENOMEM);
2279
2280	mutex_lock(&regulator_list_mutex);
2281
2282	mutex_init(&rdev->mutex);
2283	rdev->reg_data = driver_data;
2284	rdev->owner = regulator_desc->owner;
2285	rdev->desc = regulator_desc;
2286	INIT_LIST_HEAD(&rdev->consumer_list);
2287	INIT_LIST_HEAD(&rdev->supply_list);
2288	INIT_LIST_HEAD(&rdev->list);
2289	INIT_LIST_HEAD(&rdev->slist);
2290	BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
2291
2292	/* preform any regulator specific init */
2293	if (init_data->regulator_init) {
2294		ret = init_data->regulator_init(rdev->reg_data);
2295		if (ret < 0)
2296			goto clean;
2297	}
2298
2299	/* register with sysfs */
2300	rdev->dev.class = &regulator_class;
2301	rdev->dev.parent = dev;
2302	dev_set_name(&rdev->dev, "regulator.%d",
2303		     atomic_inc_return(&regulator_no) - 1);
2304	ret = device_register(&rdev->dev);
2305	if (ret != 0)
2306		goto clean;
2307
2308	dev_set_drvdata(&rdev->dev, rdev);
2309
2310	/* set regulator constraints */
2311	ret = set_machine_constraints(rdev, &init_data->constraints);
2312	if (ret < 0)
2313		goto scrub;
2314
2315	/* add attributes supported by this regulator */
2316	ret = add_regulator_attributes(rdev);
2317	if (ret < 0)
2318		goto scrub;
2319
2320	/* set supply regulator if it exists */
2321	if (init_data->supply_regulator && init_data->supply_regulator_dev) {
2322		dev_err(dev,
2323			"Supply regulator specified by both name and dev\n");
2324		goto scrub;
2325	}
2326
2327	if (init_data->supply_regulator) {
2328		struct regulator_dev *r;
2329		int found = 0;
2330
2331		list_for_each_entry(r, &regulator_list, list) {
2332			if (strcmp(rdev_get_name(r),
2333				   init_data->supply_regulator) == 0) {
2334				found = 1;
2335				break;
2336			}
2337		}
2338
2339		if (!found) {
2340			dev_err(dev, "Failed to find supply %s\n",
2341				init_data->supply_regulator);
2342			goto scrub;
2343		}
2344
2345		ret = set_supply(rdev, r);
2346		if (ret < 0)
2347			goto scrub;
2348	}
2349
2350	if (init_data->supply_regulator_dev) {
2351		dev_warn(dev, "Uses supply_regulator_dev instead of regulator_supply\n");
2352		ret = set_supply(rdev,
2353			dev_get_drvdata(init_data->supply_regulator_dev));
2354		if (ret < 0)
2355			goto scrub;
2356	}
2357
2358	/* add consumers devices */
2359	for (i = 0; i < init_data->num_consumer_supplies; i++) {
2360		ret = set_consumer_device_supply(rdev,
2361			init_data->consumer_supplies[i].dev,
2362			init_data->consumer_supplies[i].dev_name,
2363			init_data->consumer_supplies[i].supply);
2364		if (ret < 0)
2365			goto unset_supplies;
2366	}
2367
2368	list_add(&rdev->list, &regulator_list);
2369out:
2370	mutex_unlock(&regulator_list_mutex);
2371	return rdev;
2372
2373unset_supplies:
2374	unset_regulator_supplies(rdev);
2375
2376scrub:
2377	device_unregister(&rdev->dev);
2378	/* device core frees rdev */
2379	rdev = ERR_PTR(ret);
2380	goto out;
2381
2382clean:
2383	kfree(rdev);
2384	rdev = ERR_PTR(ret);
2385	goto out;
2386}
2387EXPORT_SYMBOL_GPL(regulator_register);
2388
2389/**
2390 * regulator_unregister - unregister regulator
2391 * @rdev: regulator to unregister
2392 *
2393 * Called by regulator drivers to unregister a regulator.
2394 */
2395void regulator_unregister(struct regulator_dev *rdev)
2396{
2397	if (rdev == NULL)
2398		return;
2399
2400	mutex_lock(&regulator_list_mutex);
2401	WARN_ON(rdev->open_count);
2402	unset_regulator_supplies(rdev);
2403	list_del(&rdev->list);
2404	if (rdev->supply)
2405		sysfs_remove_link(&rdev->dev.kobj, "supply");
2406	device_unregister(&rdev->dev);
2407	mutex_unlock(&regulator_list_mutex);
2408}
2409EXPORT_SYMBOL_GPL(regulator_unregister);
2410
2411/**
2412 * regulator_suspend_prepare - prepare regulators for system wide suspend
2413 * @state: system suspend state
2414 *
2415 * Configure each regulator with it's suspend operating parameters for state.
2416 * This will usually be called by machine suspend code prior to supending.
2417 */
2418int regulator_suspend_prepare(suspend_state_t state)
2419{
2420	struct regulator_dev *rdev;
2421	int ret = 0;
2422
2423	/* ON is handled by regulator active state */
2424	if (state == PM_SUSPEND_ON)
2425		return -EINVAL;
2426
2427	mutex_lock(&regulator_list_mutex);
2428	list_for_each_entry(rdev, &regulator_list, list) {
2429
2430		mutex_lock(&rdev->mutex);
2431		ret = suspend_prepare(rdev, state);
2432		mutex_unlock(&rdev->mutex);
2433
2434		if (ret < 0) {
2435			printk(KERN_ERR "%s: failed to prepare %s\n",
2436				__func__, rdev_get_name(rdev));
2437			goto out;
2438		}
2439	}
2440out:
2441	mutex_unlock(&regulator_list_mutex);
2442	return ret;
2443}
2444EXPORT_SYMBOL_GPL(regulator_suspend_prepare);
2445
2446/**
2447 * regulator_has_full_constraints - the system has fully specified constraints
2448 *
2449 * Calling this function will cause the regulator API to disable all
2450 * regulators which have a zero use count and don't have an always_on
2451 * constraint in a late_initcall.
2452 *
2453 * The intention is that this will become the default behaviour in a
2454 * future kernel release so users are encouraged to use this facility
2455 * now.
2456 */
2457void regulator_has_full_constraints(void)
2458{
2459	has_full_constraints = 1;
2460}
2461EXPORT_SYMBOL_GPL(regulator_has_full_constraints);
2462
2463/**
2464 * rdev_get_drvdata - get rdev regulator driver data
2465 * @rdev: regulator
2466 *
2467 * Get rdev regulator driver private data. This call can be used in the
2468 * regulator driver context.
2469 */
2470void *rdev_get_drvdata(struct regulator_dev *rdev)
2471{
2472	return rdev->reg_data;
2473}
2474EXPORT_SYMBOL_GPL(rdev_get_drvdata);
2475
2476/**
2477 * regulator_get_drvdata - get regulator driver data
2478 * @regulator: regulator
2479 *
2480 * Get regulator driver private data. This call can be used in the consumer
2481 * driver context when non API regulator specific functions need to be called.
2482 */
2483void *regulator_get_drvdata(struct regulator *regulator)
2484{
2485	return regulator->rdev->reg_data;
2486}
2487EXPORT_SYMBOL_GPL(regulator_get_drvdata);
2488
2489/**
2490 * regulator_set_drvdata - set regulator driver data
2491 * @regulator: regulator
2492 * @data: data
2493 */
2494void regulator_set_drvdata(struct regulator *regulator, void *data)
2495{
2496	regulator->rdev->reg_data = data;
2497}
2498EXPORT_SYMBOL_GPL(regulator_set_drvdata);
2499
2500/**
2501 * regulator_get_id - get regulator ID
2502 * @rdev: regulator
2503 */
2504int rdev_get_id(struct regulator_dev *rdev)
2505{
2506	return rdev->desc->id;
2507}
2508EXPORT_SYMBOL_GPL(rdev_get_id);
2509
2510struct device *rdev_get_dev(struct regulator_dev *rdev)
2511{
2512	return &rdev->dev;
2513}
2514EXPORT_SYMBOL_GPL(rdev_get_dev);
2515
2516void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
2517{
2518	return reg_init_data->driver_data;
2519}
2520EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
2521
2522static int __init regulator_init(void)
2523{
2524	int ret;
2525
2526	printk(KERN_INFO "regulator: core version %s\n", REGULATOR_VERSION);
2527
2528	ret = class_register(&regulator_class);
2529
2530	regulator_dummy_init();
2531
2532	return ret;
2533}
2534
2535/* init early to allow our consumers to complete system booting */
2536core_initcall(regulator_init);
2537
2538static int __init regulator_init_complete(void)
2539{
2540	struct regulator_dev *rdev;
2541	struct regulator_ops *ops;
2542	struct regulation_constraints *c;
2543	int enabled, ret;
2544	const char *name;
2545
2546	mutex_lock(&regulator_list_mutex);
2547
2548	/* If we have a full configuration then disable any regulators
2549	 * which are not in use or always_on.  This will become the
2550	 * default behaviour in the future.
2551	 */
2552	list_for_each_entry(rdev, &regulator_list, list) {
2553		ops = rdev->desc->ops;
2554		c = rdev->constraints;
2555
2556		name = rdev_get_name(rdev);
2557
2558		if (!ops->disable || (c && c->always_on))
2559			continue;
2560
2561		mutex_lock(&rdev->mutex);
2562
2563		if (rdev->use_count)
2564			goto unlock;
2565
2566		/* If we can't read the status assume it's on. */
2567		if (ops->is_enabled)
2568			enabled = ops->is_enabled(rdev);
2569		else
2570			enabled = 1;
2571
2572		if (!enabled)
2573			goto unlock;
2574
2575		if (has_full_constraints) {
2576			/* We log since this may kill the system if it
2577			 * goes wrong. */
2578			printk(KERN_INFO "%s: disabling %s\n",
2579			       __func__, name);
2580			ret = ops->disable(rdev);
2581			if (ret != 0) {
2582				printk(KERN_ERR
2583				       "%s: couldn't disable %s: %d\n",
2584				       __func__, name, ret);
2585			}
2586		} else {
2587			/* The intention is that in future we will
2588			 * assume that full constraints are provided
2589			 * so warn even if we aren't going to do
2590			 * anything here.
2591			 */
2592			printk(KERN_WARNING
2593			       "%s: incomplete constraints, leaving %s on\n",
2594			       __func__, name);
2595		}
2596
2597unlock:
2598		mutex_unlock(&rdev->mutex);
2599	}
2600
2601	mutex_unlock(&regulator_list_mutex);
2602
2603	return 0;
2604}
2605late_initcall(regulator_init_complete);
2606