core.c revision e79055d62ea6ca3c36962209f4c819614972c95a
1/*
2 * core.c  --  Voltage/Current Regulator framework.
3 *
4 * Copyright 2007, 2008 Wolfson Microelectronics PLC.
5 * Copyright 2008 SlimLogic Ltd.
6 *
7 * Author: Liam Girdwood <lrg@slimlogic.co.uk>
8 *
9 *  This program is free software; you can redistribute  it and/or modify it
10 *  under  the terms of  the GNU General  Public License as published by the
11 *  Free Software Foundation;  either version 2 of the  License, or (at your
12 *  option) any later version.
13 *
14 */
15
16#include <linux/kernel.h>
17#include <linux/init.h>
18#include <linux/device.h>
19#include <linux/err.h>
20#include <linux/mutex.h>
21#include <linux/suspend.h>
22#include <linux/regulator/consumer.h>
23#include <linux/regulator/driver.h>
24#include <linux/regulator/machine.h>
25
26#define REGULATOR_VERSION "0.5"
27
28static DEFINE_MUTEX(regulator_list_mutex);
29static LIST_HEAD(regulator_list);
30static LIST_HEAD(regulator_map_list);
31static int has_full_constraints;
32
33/*
34 * struct regulator_map
35 *
36 * Used to provide symbolic supply names to devices.
37 */
38struct regulator_map {
39	struct list_head list;
40	const char *dev_name;   /* The dev_name() for the consumer */
41	const char *supply;
42	struct regulator_dev *regulator;
43};
44
45/*
46 * struct regulator
47 *
48 * One for each consumer device.
49 */
50struct regulator {
51	struct device *dev;
52	struct list_head list;
53	int uA_load;
54	int min_uV;
55	int max_uV;
56	char *supply_name;
57	struct device_attribute dev_attr;
58	struct regulator_dev *rdev;
59};
60
61static int _regulator_is_enabled(struct regulator_dev *rdev);
62static int _regulator_disable(struct regulator_dev *rdev);
63static int _regulator_get_voltage(struct regulator_dev *rdev);
64static int _regulator_get_current_limit(struct regulator_dev *rdev);
65static unsigned int _regulator_get_mode(struct regulator_dev *rdev);
66static void _notifier_call_chain(struct regulator_dev *rdev,
67				  unsigned long event, void *data);
68
69/* gets the regulator for a given consumer device */
70static struct regulator *get_device_regulator(struct device *dev)
71{
72	struct regulator *regulator = NULL;
73	struct regulator_dev *rdev;
74
75	mutex_lock(&regulator_list_mutex);
76	list_for_each_entry(rdev, &regulator_list, list) {
77		mutex_lock(&rdev->mutex);
78		list_for_each_entry(regulator, &rdev->consumer_list, list) {
79			if (regulator->dev == dev) {
80				mutex_unlock(&rdev->mutex);
81				mutex_unlock(&regulator_list_mutex);
82				return regulator;
83			}
84		}
85		mutex_unlock(&rdev->mutex);
86	}
87	mutex_unlock(&regulator_list_mutex);
88	return NULL;
89}
90
91/* Platform voltage constraint check */
92static int regulator_check_voltage(struct regulator_dev *rdev,
93				   int *min_uV, int *max_uV)
94{
95	BUG_ON(*min_uV > *max_uV);
96
97	if (!rdev->constraints) {
98		printk(KERN_ERR "%s: no constraints for %s\n", __func__,
99		       rdev->desc->name);
100		return -ENODEV;
101	}
102	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
103		printk(KERN_ERR "%s: operation not allowed for %s\n",
104		       __func__, rdev->desc->name);
105		return -EPERM;
106	}
107
108	if (*max_uV > rdev->constraints->max_uV)
109		*max_uV = rdev->constraints->max_uV;
110	if (*min_uV < rdev->constraints->min_uV)
111		*min_uV = rdev->constraints->min_uV;
112
113	if (*min_uV > *max_uV)
114		return -EINVAL;
115
116	return 0;
117}
118
119/* current constraint check */
120static int regulator_check_current_limit(struct regulator_dev *rdev,
121					int *min_uA, int *max_uA)
122{
123	BUG_ON(*min_uA > *max_uA);
124
125	if (!rdev->constraints) {
126		printk(KERN_ERR "%s: no constraints for %s\n", __func__,
127		       rdev->desc->name);
128		return -ENODEV;
129	}
130	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_CURRENT)) {
131		printk(KERN_ERR "%s: operation not allowed for %s\n",
132		       __func__, rdev->desc->name);
133		return -EPERM;
134	}
135
136	if (*max_uA > rdev->constraints->max_uA)
137		*max_uA = rdev->constraints->max_uA;
138	if (*min_uA < rdev->constraints->min_uA)
139		*min_uA = rdev->constraints->min_uA;
140
141	if (*min_uA > *max_uA)
142		return -EINVAL;
143
144	return 0;
145}
146
147/* operating mode constraint check */
148static int regulator_check_mode(struct regulator_dev *rdev, int mode)
149{
150	switch (mode) {
151	case REGULATOR_MODE_FAST:
152	case REGULATOR_MODE_NORMAL:
153	case REGULATOR_MODE_IDLE:
154	case REGULATOR_MODE_STANDBY:
155		break;
156	default:
157		return -EINVAL;
158	}
159
160	if (!rdev->constraints) {
161		printk(KERN_ERR "%s: no constraints for %s\n", __func__,
162		       rdev->desc->name);
163		return -ENODEV;
164	}
165	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_MODE)) {
166		printk(KERN_ERR "%s: operation not allowed for %s\n",
167		       __func__, rdev->desc->name);
168		return -EPERM;
169	}
170	if (!(rdev->constraints->valid_modes_mask & mode)) {
171		printk(KERN_ERR "%s: invalid mode %x for %s\n",
172		       __func__, mode, rdev->desc->name);
173		return -EINVAL;
174	}
175	return 0;
176}
177
178/* dynamic regulator mode switching constraint check */
179static int regulator_check_drms(struct regulator_dev *rdev)
180{
181	if (!rdev->constraints) {
182		printk(KERN_ERR "%s: no constraints for %s\n", __func__,
183		       rdev->desc->name);
184		return -ENODEV;
185	}
186	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS)) {
187		printk(KERN_ERR "%s: operation not allowed for %s\n",
188		       __func__, rdev->desc->name);
189		return -EPERM;
190	}
191	return 0;
192}
193
194static ssize_t device_requested_uA_show(struct device *dev,
195			     struct device_attribute *attr, char *buf)
196{
197	struct regulator *regulator;
198
199	regulator = get_device_regulator(dev);
200	if (regulator == NULL)
201		return 0;
202
203	return sprintf(buf, "%d\n", regulator->uA_load);
204}
205
206static ssize_t regulator_uV_show(struct device *dev,
207				struct device_attribute *attr, char *buf)
208{
209	struct regulator_dev *rdev = dev_get_drvdata(dev);
210	ssize_t ret;
211
212	mutex_lock(&rdev->mutex);
213	ret = sprintf(buf, "%d\n", _regulator_get_voltage(rdev));
214	mutex_unlock(&rdev->mutex);
215
216	return ret;
217}
218static DEVICE_ATTR(microvolts, 0444, regulator_uV_show, NULL);
219
220static ssize_t regulator_uA_show(struct device *dev,
221				struct device_attribute *attr, char *buf)
222{
223	struct regulator_dev *rdev = dev_get_drvdata(dev);
224
225	return sprintf(buf, "%d\n", _regulator_get_current_limit(rdev));
226}
227static DEVICE_ATTR(microamps, 0444, regulator_uA_show, NULL);
228
229static ssize_t regulator_name_show(struct device *dev,
230			     struct device_attribute *attr, char *buf)
231{
232	struct regulator_dev *rdev = dev_get_drvdata(dev);
233	const char *name;
234
235	if (rdev->constraints && rdev->constraints->name)
236		name = rdev->constraints->name;
237	else if (rdev->desc->name)
238		name = rdev->desc->name;
239	else
240		name = "";
241
242	return sprintf(buf, "%s\n", name);
243}
244
245static ssize_t regulator_print_opmode(char *buf, int mode)
246{
247	switch (mode) {
248	case REGULATOR_MODE_FAST:
249		return sprintf(buf, "fast\n");
250	case REGULATOR_MODE_NORMAL:
251		return sprintf(buf, "normal\n");
252	case REGULATOR_MODE_IDLE:
253		return sprintf(buf, "idle\n");
254	case REGULATOR_MODE_STANDBY:
255		return sprintf(buf, "standby\n");
256	}
257	return sprintf(buf, "unknown\n");
258}
259
260static ssize_t regulator_opmode_show(struct device *dev,
261				    struct device_attribute *attr, char *buf)
262{
263	struct regulator_dev *rdev = dev_get_drvdata(dev);
264
265	return regulator_print_opmode(buf, _regulator_get_mode(rdev));
266}
267static DEVICE_ATTR(opmode, 0444, regulator_opmode_show, NULL);
268
269static ssize_t regulator_print_state(char *buf, int state)
270{
271	if (state > 0)
272		return sprintf(buf, "enabled\n");
273	else if (state == 0)
274		return sprintf(buf, "disabled\n");
275	else
276		return sprintf(buf, "unknown\n");
277}
278
279static ssize_t regulator_state_show(struct device *dev,
280				   struct device_attribute *attr, char *buf)
281{
282	struct regulator_dev *rdev = dev_get_drvdata(dev);
283	ssize_t ret;
284
285	mutex_lock(&rdev->mutex);
286	ret = regulator_print_state(buf, _regulator_is_enabled(rdev));
287	mutex_unlock(&rdev->mutex);
288
289	return ret;
290}
291static DEVICE_ATTR(state, 0444, regulator_state_show, NULL);
292
293static ssize_t regulator_status_show(struct device *dev,
294				   struct device_attribute *attr, char *buf)
295{
296	struct regulator_dev *rdev = dev_get_drvdata(dev);
297	int status;
298	char *label;
299
300	status = rdev->desc->ops->get_status(rdev);
301	if (status < 0)
302		return status;
303
304	switch (status) {
305	case REGULATOR_STATUS_OFF:
306		label = "off";
307		break;
308	case REGULATOR_STATUS_ON:
309		label = "on";
310		break;
311	case REGULATOR_STATUS_ERROR:
312		label = "error";
313		break;
314	case REGULATOR_STATUS_FAST:
315		label = "fast";
316		break;
317	case REGULATOR_STATUS_NORMAL:
318		label = "normal";
319		break;
320	case REGULATOR_STATUS_IDLE:
321		label = "idle";
322		break;
323	case REGULATOR_STATUS_STANDBY:
324		label = "standby";
325		break;
326	default:
327		return -ERANGE;
328	}
329
330	return sprintf(buf, "%s\n", label);
331}
332static DEVICE_ATTR(status, 0444, regulator_status_show, NULL);
333
334static ssize_t regulator_min_uA_show(struct device *dev,
335				    struct device_attribute *attr, char *buf)
336{
337	struct regulator_dev *rdev = dev_get_drvdata(dev);
338
339	if (!rdev->constraints)
340		return sprintf(buf, "constraint not defined\n");
341
342	return sprintf(buf, "%d\n", rdev->constraints->min_uA);
343}
344static DEVICE_ATTR(min_microamps, 0444, regulator_min_uA_show, NULL);
345
346static ssize_t regulator_max_uA_show(struct device *dev,
347				    struct device_attribute *attr, char *buf)
348{
349	struct regulator_dev *rdev = dev_get_drvdata(dev);
350
351	if (!rdev->constraints)
352		return sprintf(buf, "constraint not defined\n");
353
354	return sprintf(buf, "%d\n", rdev->constraints->max_uA);
355}
356static DEVICE_ATTR(max_microamps, 0444, regulator_max_uA_show, NULL);
357
358static ssize_t regulator_min_uV_show(struct device *dev,
359				    struct device_attribute *attr, char *buf)
360{
361	struct regulator_dev *rdev = dev_get_drvdata(dev);
362
363	if (!rdev->constraints)
364		return sprintf(buf, "constraint not defined\n");
365
366	return sprintf(buf, "%d\n", rdev->constraints->min_uV);
367}
368static DEVICE_ATTR(min_microvolts, 0444, regulator_min_uV_show, NULL);
369
370static ssize_t regulator_max_uV_show(struct device *dev,
371				    struct device_attribute *attr, char *buf)
372{
373	struct regulator_dev *rdev = dev_get_drvdata(dev);
374
375	if (!rdev->constraints)
376		return sprintf(buf, "constraint not defined\n");
377
378	return sprintf(buf, "%d\n", rdev->constraints->max_uV);
379}
380static DEVICE_ATTR(max_microvolts, 0444, regulator_max_uV_show, NULL);
381
382static ssize_t regulator_total_uA_show(struct device *dev,
383				      struct device_attribute *attr, char *buf)
384{
385	struct regulator_dev *rdev = dev_get_drvdata(dev);
386	struct regulator *regulator;
387	int uA = 0;
388
389	mutex_lock(&rdev->mutex);
390	list_for_each_entry(regulator, &rdev->consumer_list, list)
391	    uA += regulator->uA_load;
392	mutex_unlock(&rdev->mutex);
393	return sprintf(buf, "%d\n", uA);
394}
395static DEVICE_ATTR(requested_microamps, 0444, regulator_total_uA_show, NULL);
396
397static ssize_t regulator_num_users_show(struct device *dev,
398				      struct device_attribute *attr, char *buf)
399{
400	struct regulator_dev *rdev = dev_get_drvdata(dev);
401	return sprintf(buf, "%d\n", rdev->use_count);
402}
403
404static ssize_t regulator_type_show(struct device *dev,
405				  struct device_attribute *attr, char *buf)
406{
407	struct regulator_dev *rdev = dev_get_drvdata(dev);
408
409	switch (rdev->desc->type) {
410	case REGULATOR_VOLTAGE:
411		return sprintf(buf, "voltage\n");
412	case REGULATOR_CURRENT:
413		return sprintf(buf, "current\n");
414	}
415	return sprintf(buf, "unknown\n");
416}
417
418static ssize_t regulator_suspend_mem_uV_show(struct device *dev,
419				struct device_attribute *attr, char *buf)
420{
421	struct regulator_dev *rdev = dev_get_drvdata(dev);
422
423	return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
424}
425static DEVICE_ATTR(suspend_mem_microvolts, 0444,
426		regulator_suspend_mem_uV_show, NULL);
427
428static ssize_t regulator_suspend_disk_uV_show(struct device *dev,
429				struct device_attribute *attr, char *buf)
430{
431	struct regulator_dev *rdev = dev_get_drvdata(dev);
432
433	return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
434}
435static DEVICE_ATTR(suspend_disk_microvolts, 0444,
436		regulator_suspend_disk_uV_show, NULL);
437
438static ssize_t regulator_suspend_standby_uV_show(struct device *dev,
439				struct device_attribute *attr, char *buf)
440{
441	struct regulator_dev *rdev = dev_get_drvdata(dev);
442
443	return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
444}
445static DEVICE_ATTR(suspend_standby_microvolts, 0444,
446		regulator_suspend_standby_uV_show, NULL);
447
448static ssize_t regulator_suspend_mem_mode_show(struct device *dev,
449				struct device_attribute *attr, char *buf)
450{
451	struct regulator_dev *rdev = dev_get_drvdata(dev);
452
453	return regulator_print_opmode(buf,
454		rdev->constraints->state_mem.mode);
455}
456static DEVICE_ATTR(suspend_mem_mode, 0444,
457		regulator_suspend_mem_mode_show, NULL);
458
459static ssize_t regulator_suspend_disk_mode_show(struct device *dev,
460				struct device_attribute *attr, char *buf)
461{
462	struct regulator_dev *rdev = dev_get_drvdata(dev);
463
464	return regulator_print_opmode(buf,
465		rdev->constraints->state_disk.mode);
466}
467static DEVICE_ATTR(suspend_disk_mode, 0444,
468		regulator_suspend_disk_mode_show, NULL);
469
470static ssize_t regulator_suspend_standby_mode_show(struct device *dev,
471				struct device_attribute *attr, char *buf)
472{
473	struct regulator_dev *rdev = dev_get_drvdata(dev);
474
475	return regulator_print_opmode(buf,
476		rdev->constraints->state_standby.mode);
477}
478static DEVICE_ATTR(suspend_standby_mode, 0444,
479		regulator_suspend_standby_mode_show, NULL);
480
481static ssize_t regulator_suspend_mem_state_show(struct device *dev,
482				   struct device_attribute *attr, char *buf)
483{
484	struct regulator_dev *rdev = dev_get_drvdata(dev);
485
486	return regulator_print_state(buf,
487			rdev->constraints->state_mem.enabled);
488}
489static DEVICE_ATTR(suspend_mem_state, 0444,
490		regulator_suspend_mem_state_show, NULL);
491
492static ssize_t regulator_suspend_disk_state_show(struct device *dev,
493				   struct device_attribute *attr, char *buf)
494{
495	struct regulator_dev *rdev = dev_get_drvdata(dev);
496
497	return regulator_print_state(buf,
498			rdev->constraints->state_disk.enabled);
499}
500static DEVICE_ATTR(suspend_disk_state, 0444,
501		regulator_suspend_disk_state_show, NULL);
502
503static ssize_t regulator_suspend_standby_state_show(struct device *dev,
504				   struct device_attribute *attr, char *buf)
505{
506	struct regulator_dev *rdev = dev_get_drvdata(dev);
507
508	return regulator_print_state(buf,
509			rdev->constraints->state_standby.enabled);
510}
511static DEVICE_ATTR(suspend_standby_state, 0444,
512		regulator_suspend_standby_state_show, NULL);
513
514
515/*
516 * These are the only attributes are present for all regulators.
517 * Other attributes are a function of regulator functionality.
518 */
519static struct device_attribute regulator_dev_attrs[] = {
520	__ATTR(name, 0444, regulator_name_show, NULL),
521	__ATTR(num_users, 0444, regulator_num_users_show, NULL),
522	__ATTR(type, 0444, regulator_type_show, NULL),
523	__ATTR_NULL,
524};
525
526static void regulator_dev_release(struct device *dev)
527{
528	struct regulator_dev *rdev = dev_get_drvdata(dev);
529	kfree(rdev);
530}
531
532static struct class regulator_class = {
533	.name = "regulator",
534	.dev_release = regulator_dev_release,
535	.dev_attrs = regulator_dev_attrs,
536};
537
538/* Calculate the new optimum regulator operating mode based on the new total
539 * consumer load. All locks held by caller */
540static void drms_uA_update(struct regulator_dev *rdev)
541{
542	struct regulator *sibling;
543	int current_uA = 0, output_uV, input_uV, err;
544	unsigned int mode;
545
546	err = regulator_check_drms(rdev);
547	if (err < 0 || !rdev->desc->ops->get_optimum_mode ||
548	    !rdev->desc->ops->get_voltage || !rdev->desc->ops->set_mode)
549		return;
550
551	/* get output voltage */
552	output_uV = rdev->desc->ops->get_voltage(rdev);
553	if (output_uV <= 0)
554		return;
555
556	/* get input voltage */
557	if (rdev->supply && rdev->supply->desc->ops->get_voltage)
558		input_uV = rdev->supply->desc->ops->get_voltage(rdev->supply);
559	else
560		input_uV = rdev->constraints->input_uV;
561	if (input_uV <= 0)
562		return;
563
564	/* calc total requested load */
565	list_for_each_entry(sibling, &rdev->consumer_list, list)
566	    current_uA += sibling->uA_load;
567
568	/* now get the optimum mode for our new total regulator load */
569	mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
570						  output_uV, current_uA);
571
572	/* check the new mode is allowed */
573	err = regulator_check_mode(rdev, mode);
574	if (err == 0)
575		rdev->desc->ops->set_mode(rdev, mode);
576}
577
578static int suspend_set_state(struct regulator_dev *rdev,
579	struct regulator_state *rstate)
580{
581	int ret = 0;
582
583	/* enable & disable are mandatory for suspend control */
584	if (!rdev->desc->ops->set_suspend_enable ||
585		!rdev->desc->ops->set_suspend_disable) {
586		printk(KERN_ERR "%s: no way to set suspend state\n",
587			__func__);
588		return -EINVAL;
589	}
590
591	if (rstate->enabled)
592		ret = rdev->desc->ops->set_suspend_enable(rdev);
593	else
594		ret = rdev->desc->ops->set_suspend_disable(rdev);
595	if (ret < 0) {
596		printk(KERN_ERR "%s: failed to enabled/disable\n", __func__);
597		return ret;
598	}
599
600	if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
601		ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
602		if (ret < 0) {
603			printk(KERN_ERR "%s: failed to set voltage\n",
604				__func__);
605			return ret;
606		}
607	}
608
609	if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
610		ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
611		if (ret < 0) {
612			printk(KERN_ERR "%s: failed to set mode\n", __func__);
613			return ret;
614		}
615	}
616	return ret;
617}
618
619/* locks held by caller */
620static int suspend_prepare(struct regulator_dev *rdev, suspend_state_t state)
621{
622	if (!rdev->constraints)
623		return -EINVAL;
624
625	switch (state) {
626	case PM_SUSPEND_STANDBY:
627		return suspend_set_state(rdev,
628			&rdev->constraints->state_standby);
629	case PM_SUSPEND_MEM:
630		return suspend_set_state(rdev,
631			&rdev->constraints->state_mem);
632	case PM_SUSPEND_MAX:
633		return suspend_set_state(rdev,
634			&rdev->constraints->state_disk);
635	default:
636		return -EINVAL;
637	}
638}
639
640static void print_constraints(struct regulator_dev *rdev)
641{
642	struct regulation_constraints *constraints = rdev->constraints;
643	char buf[80];
644	int count;
645
646	if (rdev->desc->type == REGULATOR_VOLTAGE) {
647		if (constraints->min_uV == constraints->max_uV)
648			count = sprintf(buf, "%d mV ",
649					constraints->min_uV / 1000);
650		else
651			count = sprintf(buf, "%d <--> %d mV ",
652					constraints->min_uV / 1000,
653					constraints->max_uV / 1000);
654	} else {
655		if (constraints->min_uA == constraints->max_uA)
656			count = sprintf(buf, "%d mA ",
657					constraints->min_uA / 1000);
658		else
659			count = sprintf(buf, "%d <--> %d mA ",
660					constraints->min_uA / 1000,
661					constraints->max_uA / 1000);
662	}
663	if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
664		count += sprintf(buf + count, "fast ");
665	if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
666		count += sprintf(buf + count, "normal ");
667	if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
668		count += sprintf(buf + count, "idle ");
669	if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
670		count += sprintf(buf + count, "standby");
671
672	printk(KERN_INFO "regulator: %s: %s\n", rdev->desc->name, buf);
673}
674
675static int machine_constraints_voltage(struct regulator_dev *rdev,
676	const char *name, struct regulation_constraints *constraints)
677{
678	struct regulator_ops *ops = rdev->desc->ops;
679
680	/* constrain machine-level voltage specs to fit
681	 * the actual range supported by this regulator.
682	 */
683	if (ops->list_voltage && rdev->desc->n_voltages) {
684		int	count = rdev->desc->n_voltages;
685		int	i;
686		int	min_uV = INT_MAX;
687		int	max_uV = INT_MIN;
688		int	cmin = constraints->min_uV;
689		int	cmax = constraints->max_uV;
690
691		/* it's safe to autoconfigure fixed-voltage supplies
692		   and the constraints are used by list_voltage. */
693		if (count == 1 && !cmin) {
694			cmin = 1;
695			cmax = INT_MAX;
696			constraints->min_uV = cmin;
697			constraints->max_uV = cmax;
698		}
699
700		/* voltage constraints are optional */
701		if ((cmin == 0) && (cmax == 0))
702			return 0;
703
704		/* else require explicit machine-level constraints */
705		if (cmin <= 0 || cmax <= 0 || cmax < cmin) {
706			pr_err("%s: %s '%s' voltage constraints\n",
707				       __func__, "invalid", name);
708			return -EINVAL;
709		}
710
711		/* initial: [cmin..cmax] valid, [min_uV..max_uV] not */
712		for (i = 0; i < count; i++) {
713			int	value;
714
715			value = ops->list_voltage(rdev, i);
716			if (value <= 0)
717				continue;
718
719			/* maybe adjust [min_uV..max_uV] */
720			if (value >= cmin && value < min_uV)
721				min_uV = value;
722			if (value <= cmax && value > max_uV)
723				max_uV = value;
724		}
725
726		/* final: [min_uV..max_uV] valid iff constraints valid */
727		if (max_uV < min_uV) {
728			pr_err("%s: %s '%s' voltage constraints\n",
729				       __func__, "unsupportable", name);
730			return -EINVAL;
731		}
732
733		/* use regulator's subset of machine constraints */
734		if (constraints->min_uV < min_uV) {
735			pr_debug("%s: override '%s' %s, %d -> %d\n",
736				       __func__, name, "min_uV",
737					constraints->min_uV, min_uV);
738			constraints->min_uV = min_uV;
739		}
740		if (constraints->max_uV > max_uV) {
741			pr_debug("%s: override '%s' %s, %d -> %d\n",
742				       __func__, name, "max_uV",
743					constraints->max_uV, max_uV);
744			constraints->max_uV = max_uV;
745		}
746	}
747
748	return 0;
749}
750
751/**
752 * set_machine_constraints - sets regulator constraints
753 * @rdev: regulator source
754 * @constraints: constraints to apply
755 *
756 * Allows platform initialisation code to define and constrain
757 * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
758 * Constraints *must* be set by platform code in order for some
759 * regulator operations to proceed i.e. set_voltage, set_current_limit,
760 * set_mode.
761 */
762static int set_machine_constraints(struct regulator_dev *rdev,
763	struct regulation_constraints *constraints)
764{
765	int ret = 0;
766	const char *name;
767	struct regulator_ops *ops = rdev->desc->ops;
768
769	if (constraints->name)
770		name = constraints->name;
771	else if (rdev->desc->name)
772		name = rdev->desc->name;
773	else
774		name = "regulator";
775
776	ret = machine_constraints_voltage(rdev, name, constraints);
777	if (ret != 0)
778		goto out;
779
780	rdev->constraints = constraints;
781
782	/* do we need to apply the constraint voltage */
783	if (rdev->constraints->apply_uV &&
784		rdev->constraints->min_uV == rdev->constraints->max_uV &&
785		ops->set_voltage) {
786		ret = ops->set_voltage(rdev,
787			rdev->constraints->min_uV, rdev->constraints->max_uV);
788			if (ret < 0) {
789				printk(KERN_ERR "%s: failed to apply %duV constraint to %s\n",
790				       __func__,
791				       rdev->constraints->min_uV, name);
792				rdev->constraints = NULL;
793				goto out;
794			}
795	}
796
797	/* do we need to setup our suspend state */
798	if (constraints->initial_state) {
799		ret = suspend_prepare(rdev, constraints->initial_state);
800		if (ret < 0) {
801			printk(KERN_ERR "%s: failed to set suspend state for %s\n",
802			       __func__, name);
803			rdev->constraints = NULL;
804			goto out;
805		}
806	}
807
808	if (constraints->initial_mode) {
809		if (!ops->set_mode) {
810			printk(KERN_ERR "%s: no set_mode operation for %s\n",
811			       __func__, name);
812			ret = -EINVAL;
813			goto out;
814		}
815
816		ret = ops->set_mode(rdev, constraints->initial_mode);
817		if (ret < 0) {
818			printk(KERN_ERR
819			       "%s: failed to set initial mode for %s: %d\n",
820			       __func__, name, ret);
821			goto out;
822		}
823	}
824
825	/* If the constraints say the regulator should be on at this point
826	 * and we have control then make sure it is enabled.
827	 */
828	if ((constraints->always_on || constraints->boot_on) && ops->enable) {
829		ret = ops->enable(rdev);
830		if (ret < 0) {
831			printk(KERN_ERR "%s: failed to enable %s\n",
832			       __func__, name);
833			rdev->constraints = NULL;
834			goto out;
835		}
836	}
837
838	print_constraints(rdev);
839out:
840	return ret;
841}
842
843/**
844 * set_supply - set regulator supply regulator
845 * @rdev: regulator name
846 * @supply_rdev: supply regulator name
847 *
848 * Called by platform initialisation code to set the supply regulator for this
849 * regulator. This ensures that a regulators supply will also be enabled by the
850 * core if it's child is enabled.
851 */
852static int set_supply(struct regulator_dev *rdev,
853	struct regulator_dev *supply_rdev)
854{
855	int err;
856
857	err = sysfs_create_link(&rdev->dev.kobj, &supply_rdev->dev.kobj,
858				"supply");
859	if (err) {
860		printk(KERN_ERR
861		       "%s: could not add device link %s err %d\n",
862		       __func__, supply_rdev->dev.kobj.name, err);
863		       goto out;
864	}
865	rdev->supply = supply_rdev;
866	list_add(&rdev->slist, &supply_rdev->supply_list);
867out:
868	return err;
869}
870
871/**
872 * set_consumer_device_supply: Bind a regulator to a symbolic supply
873 * @rdev:         regulator source
874 * @consumer_dev: device the supply applies to
875 * @consumer_dev_name: dev_name() string for device supply applies to
876 * @supply:       symbolic name for supply
877 *
878 * Allows platform initialisation code to map physical regulator
879 * sources to symbolic names for supplies for use by devices.  Devices
880 * should use these symbolic names to request regulators, avoiding the
881 * need to provide board-specific regulator names as platform data.
882 *
883 * Only one of consumer_dev and consumer_dev_name may be specified.
884 */
885static int set_consumer_device_supply(struct regulator_dev *rdev,
886	struct device *consumer_dev, const char *consumer_dev_name,
887	const char *supply)
888{
889	struct regulator_map *node;
890	int has_dev;
891
892	if (consumer_dev && consumer_dev_name)
893		return -EINVAL;
894
895	if (!consumer_dev_name && consumer_dev)
896		consumer_dev_name = dev_name(consumer_dev);
897
898	if (supply == NULL)
899		return -EINVAL;
900
901	if (consumer_dev_name != NULL)
902		has_dev = 1;
903	else
904		has_dev = 0;
905
906	list_for_each_entry(node, &regulator_map_list, list) {
907		if (consumer_dev_name != node->dev_name)
908			continue;
909		if (strcmp(node->supply, supply) != 0)
910			continue;
911
912		dev_dbg(consumer_dev, "%s/%s is '%s' supply; fail %s/%s\n",
913				dev_name(&node->regulator->dev),
914				node->regulator->desc->name,
915				supply,
916				dev_name(&rdev->dev), rdev->desc->name);
917		return -EBUSY;
918	}
919
920	node = kzalloc(sizeof(struct regulator_map), GFP_KERNEL);
921	if (node == NULL)
922		return -ENOMEM;
923
924	node->regulator = rdev;
925	node->supply = supply;
926
927	if (has_dev) {
928		node->dev_name = kstrdup(consumer_dev_name, GFP_KERNEL);
929		if (node->dev_name == NULL) {
930			kfree(node);
931			return -ENOMEM;
932		}
933	}
934
935	list_add(&node->list, &regulator_map_list);
936	return 0;
937}
938
939static void unset_consumer_device_supply(struct regulator_dev *rdev,
940	const char *consumer_dev_name, struct device *consumer_dev)
941{
942	struct regulator_map *node, *n;
943
944	if (consumer_dev && !consumer_dev_name)
945		consumer_dev_name = dev_name(consumer_dev);
946
947	list_for_each_entry_safe(node, n, &regulator_map_list, list) {
948		if (rdev != node->regulator)
949			continue;
950
951		if (consumer_dev_name && node->dev_name &&
952		    strcmp(consumer_dev_name, node->dev_name))
953			continue;
954
955		list_del(&node->list);
956		kfree(node->dev_name);
957		kfree(node);
958		return;
959	}
960}
961
962static void unset_regulator_supplies(struct regulator_dev *rdev)
963{
964	struct regulator_map *node, *n;
965
966	list_for_each_entry_safe(node, n, &regulator_map_list, list) {
967		if (rdev == node->regulator) {
968			list_del(&node->list);
969			kfree(node->dev_name);
970			kfree(node);
971			return;
972		}
973	}
974}
975
976#define REG_STR_SIZE	32
977
978static struct regulator *create_regulator(struct regulator_dev *rdev,
979					  struct device *dev,
980					  const char *supply_name)
981{
982	struct regulator *regulator;
983	char buf[REG_STR_SIZE];
984	int err, size;
985
986	regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
987	if (regulator == NULL)
988		return NULL;
989
990	mutex_lock(&rdev->mutex);
991	regulator->rdev = rdev;
992	list_add(&regulator->list, &rdev->consumer_list);
993
994	if (dev) {
995		/* create a 'requested_microamps_name' sysfs entry */
996		size = scnprintf(buf, REG_STR_SIZE, "microamps_requested_%s",
997			supply_name);
998		if (size >= REG_STR_SIZE)
999			goto overflow_err;
1000
1001		regulator->dev = dev;
1002		regulator->dev_attr.attr.name = kstrdup(buf, GFP_KERNEL);
1003		if (regulator->dev_attr.attr.name == NULL)
1004			goto attr_name_err;
1005
1006		regulator->dev_attr.attr.owner = THIS_MODULE;
1007		regulator->dev_attr.attr.mode = 0444;
1008		regulator->dev_attr.show = device_requested_uA_show;
1009		err = device_create_file(dev, &regulator->dev_attr);
1010		if (err < 0) {
1011			printk(KERN_WARNING "%s: could not add regulator_dev"
1012				" load sysfs\n", __func__);
1013			goto attr_name_err;
1014		}
1015
1016		/* also add a link to the device sysfs entry */
1017		size = scnprintf(buf, REG_STR_SIZE, "%s-%s",
1018				 dev->kobj.name, supply_name);
1019		if (size >= REG_STR_SIZE)
1020			goto attr_err;
1021
1022		regulator->supply_name = kstrdup(buf, GFP_KERNEL);
1023		if (regulator->supply_name == NULL)
1024			goto attr_err;
1025
1026		err = sysfs_create_link(&rdev->dev.kobj, &dev->kobj,
1027					buf);
1028		if (err) {
1029			printk(KERN_WARNING
1030			       "%s: could not add device link %s err %d\n",
1031			       __func__, dev->kobj.name, err);
1032			device_remove_file(dev, &regulator->dev_attr);
1033			goto link_name_err;
1034		}
1035	}
1036	mutex_unlock(&rdev->mutex);
1037	return regulator;
1038link_name_err:
1039	kfree(regulator->supply_name);
1040attr_err:
1041	device_remove_file(regulator->dev, &regulator->dev_attr);
1042attr_name_err:
1043	kfree(regulator->dev_attr.attr.name);
1044overflow_err:
1045	list_del(&regulator->list);
1046	kfree(regulator);
1047	mutex_unlock(&rdev->mutex);
1048	return NULL;
1049}
1050
1051/* Internal regulator request function */
1052static struct regulator *_regulator_get(struct device *dev, const char *id,
1053					int exclusive)
1054{
1055	struct regulator_dev *rdev;
1056	struct regulator_map *map;
1057	struct regulator *regulator = ERR_PTR(-ENODEV);
1058	const char *devname = NULL;
1059	int ret;
1060
1061	if (id == NULL) {
1062		printk(KERN_ERR "regulator: get() with no identifier\n");
1063		return regulator;
1064	}
1065
1066	if (dev)
1067		devname = dev_name(dev);
1068
1069	mutex_lock(&regulator_list_mutex);
1070
1071	list_for_each_entry(map, &regulator_map_list, list) {
1072		/* If the mapping has a device set up it must match */
1073		if (map->dev_name &&
1074		    (!devname || strcmp(map->dev_name, devname)))
1075			continue;
1076
1077		if (strcmp(map->supply, id) == 0) {
1078			rdev = map->regulator;
1079			goto found;
1080		}
1081	}
1082	mutex_unlock(&regulator_list_mutex);
1083	return regulator;
1084
1085found:
1086	if (rdev->exclusive) {
1087		regulator = ERR_PTR(-EPERM);
1088		goto out;
1089	}
1090
1091	if (exclusive && rdev->open_count) {
1092		regulator = ERR_PTR(-EBUSY);
1093		goto out;
1094	}
1095
1096	if (!try_module_get(rdev->owner))
1097		goto out;
1098
1099	regulator = create_regulator(rdev, dev, id);
1100	if (regulator == NULL) {
1101		regulator = ERR_PTR(-ENOMEM);
1102		module_put(rdev->owner);
1103	}
1104
1105	rdev->open_count++;
1106	if (exclusive) {
1107		rdev->exclusive = 1;
1108
1109		ret = _regulator_is_enabled(rdev);
1110		if (ret > 0)
1111			rdev->use_count = 1;
1112		else
1113			rdev->use_count = 0;
1114	}
1115
1116out:
1117	mutex_unlock(&regulator_list_mutex);
1118
1119	return regulator;
1120}
1121
1122/**
1123 * regulator_get - lookup and obtain a reference to a regulator.
1124 * @dev: device for regulator "consumer"
1125 * @id: Supply name or regulator ID.
1126 *
1127 * Returns a struct regulator corresponding to the regulator producer,
1128 * or IS_ERR() condition containing errno.
1129 *
1130 * Use of supply names configured via regulator_set_device_supply() is
1131 * strongly encouraged.  It is recommended that the supply name used
1132 * should match the name used for the supply and/or the relevant
1133 * device pins in the datasheet.
1134 */
1135struct regulator *regulator_get(struct device *dev, const char *id)
1136{
1137	return _regulator_get(dev, id, 0);
1138}
1139EXPORT_SYMBOL_GPL(regulator_get);
1140
1141/**
1142 * regulator_get_exclusive - obtain exclusive access to a regulator.
1143 * @dev: device for regulator "consumer"
1144 * @id: Supply name or regulator ID.
1145 *
1146 * Returns a struct regulator corresponding to the regulator producer,
1147 * or IS_ERR() condition containing errno.  Other consumers will be
1148 * unable to obtain this reference is held and the use count for the
1149 * regulator will be initialised to reflect the current state of the
1150 * regulator.
1151 *
1152 * This is intended for use by consumers which cannot tolerate shared
1153 * use of the regulator such as those which need to force the
1154 * regulator off for correct operation of the hardware they are
1155 * controlling.
1156 *
1157 * Use of supply names configured via regulator_set_device_supply() is
1158 * strongly encouraged.  It is recommended that the supply name used
1159 * should match the name used for the supply and/or the relevant
1160 * device pins in the datasheet.
1161 */
1162struct regulator *regulator_get_exclusive(struct device *dev, const char *id)
1163{
1164	return _regulator_get(dev, id, 1);
1165}
1166EXPORT_SYMBOL_GPL(regulator_get_exclusive);
1167
1168/**
1169 * regulator_put - "free" the regulator source
1170 * @regulator: regulator source
1171 *
1172 * Note: drivers must ensure that all regulator_enable calls made on this
1173 * regulator source are balanced by regulator_disable calls prior to calling
1174 * this function.
1175 */
1176void regulator_put(struct regulator *regulator)
1177{
1178	struct regulator_dev *rdev;
1179
1180	if (regulator == NULL || IS_ERR(regulator))
1181		return;
1182
1183	mutex_lock(&regulator_list_mutex);
1184	rdev = regulator->rdev;
1185
1186	/* remove any sysfs entries */
1187	if (regulator->dev) {
1188		sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
1189		kfree(regulator->supply_name);
1190		device_remove_file(regulator->dev, &regulator->dev_attr);
1191		kfree(regulator->dev_attr.attr.name);
1192	}
1193	list_del(&regulator->list);
1194	kfree(regulator);
1195
1196	rdev->open_count--;
1197	rdev->exclusive = 0;
1198
1199	module_put(rdev->owner);
1200	mutex_unlock(&regulator_list_mutex);
1201}
1202EXPORT_SYMBOL_GPL(regulator_put);
1203
1204static int _regulator_can_change_status(struct regulator_dev *rdev)
1205{
1206	if (!rdev->constraints)
1207		return 0;
1208
1209	if (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_STATUS)
1210		return 1;
1211	else
1212		return 0;
1213}
1214
1215/* locks held by regulator_enable() */
1216static int _regulator_enable(struct regulator_dev *rdev)
1217{
1218	int ret;
1219
1220	/* do we need to enable the supply regulator first */
1221	if (rdev->supply) {
1222		ret = _regulator_enable(rdev->supply);
1223		if (ret < 0) {
1224			printk(KERN_ERR "%s: failed to enable %s: %d\n",
1225			       __func__, rdev->desc->name, ret);
1226			return ret;
1227		}
1228	}
1229
1230	/* check voltage and requested load before enabling */
1231	if (rdev->constraints &&
1232	    (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS))
1233		drms_uA_update(rdev);
1234
1235	if (rdev->use_count == 0) {
1236		/* The regulator may on if it's not switchable or left on */
1237		ret = _regulator_is_enabled(rdev);
1238		if (ret == -EINVAL || ret == 0) {
1239			if (!_regulator_can_change_status(rdev))
1240				return -EPERM;
1241
1242			if (rdev->desc->ops->enable) {
1243				ret = rdev->desc->ops->enable(rdev);
1244				if (ret < 0)
1245					return ret;
1246			} else {
1247				return -EINVAL;
1248			}
1249		} else if (ret < 0) {
1250			printk(KERN_ERR "%s: is_enabled() failed for %s: %d\n",
1251			       __func__, rdev->desc->name, ret);
1252			return ret;
1253		}
1254		/* Fallthrough on positive return values - already enabled */
1255	}
1256
1257	rdev->use_count++;
1258
1259	return 0;
1260}
1261
1262/**
1263 * regulator_enable - enable regulator output
1264 * @regulator: regulator source
1265 *
1266 * Request that the regulator be enabled with the regulator output at
1267 * the predefined voltage or current value.  Calls to regulator_enable()
1268 * must be balanced with calls to regulator_disable().
1269 *
1270 * NOTE: the output value can be set by other drivers, boot loader or may be
1271 * hardwired in the regulator.
1272 */
1273int regulator_enable(struct regulator *regulator)
1274{
1275	struct regulator_dev *rdev = regulator->rdev;
1276	int ret = 0;
1277
1278	mutex_lock(&rdev->mutex);
1279	ret = _regulator_enable(rdev);
1280	mutex_unlock(&rdev->mutex);
1281	return ret;
1282}
1283EXPORT_SYMBOL_GPL(regulator_enable);
1284
1285/* locks held by regulator_disable() */
1286static int _regulator_disable(struct regulator_dev *rdev)
1287{
1288	int ret = 0;
1289
1290	if (WARN(rdev->use_count <= 0,
1291			"unbalanced disables for %s\n",
1292			rdev->desc->name))
1293		return -EIO;
1294
1295	/* are we the last user and permitted to disable ? */
1296	if (rdev->use_count == 1 &&
1297	    (rdev->constraints && !rdev->constraints->always_on)) {
1298
1299		/* we are last user */
1300		if (_regulator_can_change_status(rdev) &&
1301		    rdev->desc->ops->disable) {
1302			ret = rdev->desc->ops->disable(rdev);
1303			if (ret < 0) {
1304				printk(KERN_ERR "%s: failed to disable %s\n",
1305				       __func__, rdev->desc->name);
1306				return ret;
1307			}
1308		}
1309
1310		/* decrease our supplies ref count and disable if required */
1311		if (rdev->supply)
1312			_regulator_disable(rdev->supply);
1313
1314		rdev->use_count = 0;
1315	} else if (rdev->use_count > 1) {
1316
1317		if (rdev->constraints &&
1318			(rdev->constraints->valid_ops_mask &
1319			REGULATOR_CHANGE_DRMS))
1320			drms_uA_update(rdev);
1321
1322		rdev->use_count--;
1323	}
1324	return ret;
1325}
1326
1327/**
1328 * regulator_disable - disable regulator output
1329 * @regulator: regulator source
1330 *
1331 * Disable the regulator output voltage or current.  Calls to
1332 * regulator_enable() must be balanced with calls to
1333 * regulator_disable().
1334 *
1335 * NOTE: this will only disable the regulator output if no other consumer
1336 * devices have it enabled, the regulator device supports disabling and
1337 * machine constraints permit this operation.
1338 */
1339int regulator_disable(struct regulator *regulator)
1340{
1341	struct regulator_dev *rdev = regulator->rdev;
1342	int ret = 0;
1343
1344	mutex_lock(&rdev->mutex);
1345	ret = _regulator_disable(rdev);
1346	mutex_unlock(&rdev->mutex);
1347	return ret;
1348}
1349EXPORT_SYMBOL_GPL(regulator_disable);
1350
1351/* locks held by regulator_force_disable() */
1352static int _regulator_force_disable(struct regulator_dev *rdev)
1353{
1354	int ret = 0;
1355
1356	/* force disable */
1357	if (rdev->desc->ops->disable) {
1358		/* ah well, who wants to live forever... */
1359		ret = rdev->desc->ops->disable(rdev);
1360		if (ret < 0) {
1361			printk(KERN_ERR "%s: failed to force disable %s\n",
1362			       __func__, rdev->desc->name);
1363			return ret;
1364		}
1365		/* notify other consumers that power has been forced off */
1366		_notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE,
1367			NULL);
1368	}
1369
1370	/* decrease our supplies ref count and disable if required */
1371	if (rdev->supply)
1372		_regulator_disable(rdev->supply);
1373
1374	rdev->use_count = 0;
1375	return ret;
1376}
1377
1378/**
1379 * regulator_force_disable - force disable regulator output
1380 * @regulator: regulator source
1381 *
1382 * Forcibly disable the regulator output voltage or current.
1383 * NOTE: this *will* disable the regulator output even if other consumer
1384 * devices have it enabled. This should be used for situations when device
1385 * damage will likely occur if the regulator is not disabled (e.g. over temp).
1386 */
1387int regulator_force_disable(struct regulator *regulator)
1388{
1389	int ret;
1390
1391	mutex_lock(&regulator->rdev->mutex);
1392	regulator->uA_load = 0;
1393	ret = _regulator_force_disable(regulator->rdev);
1394	mutex_unlock(&regulator->rdev->mutex);
1395	return ret;
1396}
1397EXPORT_SYMBOL_GPL(regulator_force_disable);
1398
1399static int _regulator_is_enabled(struct regulator_dev *rdev)
1400{
1401	/* sanity check */
1402	if (!rdev->desc->ops->is_enabled)
1403		return -EINVAL;
1404
1405	return rdev->desc->ops->is_enabled(rdev);
1406}
1407
1408/**
1409 * regulator_is_enabled - is the regulator output enabled
1410 * @regulator: regulator source
1411 *
1412 * Returns positive if the regulator driver backing the source/client
1413 * has requested that the device be enabled, zero if it hasn't, else a
1414 * negative errno code.
1415 *
1416 * Note that the device backing this regulator handle can have multiple
1417 * users, so it might be enabled even if regulator_enable() was never
1418 * called for this particular source.
1419 */
1420int regulator_is_enabled(struct regulator *regulator)
1421{
1422	int ret;
1423
1424	mutex_lock(&regulator->rdev->mutex);
1425	ret = _regulator_is_enabled(regulator->rdev);
1426	mutex_unlock(&regulator->rdev->mutex);
1427
1428	return ret;
1429}
1430EXPORT_SYMBOL_GPL(regulator_is_enabled);
1431
1432/**
1433 * regulator_count_voltages - count regulator_list_voltage() selectors
1434 * @regulator: regulator source
1435 *
1436 * Returns number of selectors, or negative errno.  Selectors are
1437 * numbered starting at zero, and typically correspond to bitfields
1438 * in hardware registers.
1439 */
1440int regulator_count_voltages(struct regulator *regulator)
1441{
1442	struct regulator_dev	*rdev = regulator->rdev;
1443
1444	return rdev->desc->n_voltages ? : -EINVAL;
1445}
1446EXPORT_SYMBOL_GPL(regulator_count_voltages);
1447
1448/**
1449 * regulator_list_voltage - enumerate supported voltages
1450 * @regulator: regulator source
1451 * @selector: identify voltage to list
1452 * Context: can sleep
1453 *
1454 * Returns a voltage that can be passed to @regulator_set_voltage(),
1455 * zero if this selector code can't be used on this sytem, or a
1456 * negative errno.
1457 */
1458int regulator_list_voltage(struct regulator *regulator, unsigned selector)
1459{
1460	struct regulator_dev	*rdev = regulator->rdev;
1461	struct regulator_ops	*ops = rdev->desc->ops;
1462	int			ret;
1463
1464	if (!ops->list_voltage || selector >= rdev->desc->n_voltages)
1465		return -EINVAL;
1466
1467	mutex_lock(&rdev->mutex);
1468	ret = ops->list_voltage(rdev, selector);
1469	mutex_unlock(&rdev->mutex);
1470
1471	if (ret > 0) {
1472		if (ret < rdev->constraints->min_uV)
1473			ret = 0;
1474		else if (ret > rdev->constraints->max_uV)
1475			ret = 0;
1476	}
1477
1478	return ret;
1479}
1480EXPORT_SYMBOL_GPL(regulator_list_voltage);
1481
1482/**
1483 * regulator_is_supported_voltage - check if a voltage range can be supported
1484 *
1485 * @regulator: Regulator to check.
1486 * @min_uV: Minimum required voltage in uV.
1487 * @max_uV: Maximum required voltage in uV.
1488 *
1489 * Returns a boolean or a negative error code.
1490 */
1491int regulator_is_supported_voltage(struct regulator *regulator,
1492				   int min_uV, int max_uV)
1493{
1494	int i, voltages, ret;
1495
1496	ret = regulator_count_voltages(regulator);
1497	if (ret < 0)
1498		return ret;
1499	voltages = ret;
1500
1501	for (i = 0; i < voltages; i++) {
1502		ret = regulator_list_voltage(regulator, i);
1503
1504		if (ret >= min_uV && ret <= max_uV)
1505			return 1;
1506	}
1507
1508	return 0;
1509}
1510
1511/**
1512 * regulator_set_voltage - set regulator output voltage
1513 * @regulator: regulator source
1514 * @min_uV: Minimum required voltage in uV
1515 * @max_uV: Maximum acceptable voltage in uV
1516 *
1517 * Sets a voltage regulator to the desired output voltage. This can be set
1518 * during any regulator state. IOW, regulator can be disabled or enabled.
1519 *
1520 * If the regulator is enabled then the voltage will change to the new value
1521 * immediately otherwise if the regulator is disabled the regulator will
1522 * output at the new voltage when enabled.
1523 *
1524 * NOTE: If the regulator is shared between several devices then the lowest
1525 * request voltage that meets the system constraints will be used.
1526 * Regulator system constraints must be set for this regulator before
1527 * calling this function otherwise this call will fail.
1528 */
1529int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
1530{
1531	struct regulator_dev *rdev = regulator->rdev;
1532	int ret;
1533
1534	mutex_lock(&rdev->mutex);
1535
1536	/* sanity check */
1537	if (!rdev->desc->ops->set_voltage) {
1538		ret = -EINVAL;
1539		goto out;
1540	}
1541
1542	/* constraints check */
1543	ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
1544	if (ret < 0)
1545		goto out;
1546	regulator->min_uV = min_uV;
1547	regulator->max_uV = max_uV;
1548	ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV);
1549
1550out:
1551	_notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE, NULL);
1552	mutex_unlock(&rdev->mutex);
1553	return ret;
1554}
1555EXPORT_SYMBOL_GPL(regulator_set_voltage);
1556
1557static int _regulator_get_voltage(struct regulator_dev *rdev)
1558{
1559	/* sanity check */
1560	if (rdev->desc->ops->get_voltage)
1561		return rdev->desc->ops->get_voltage(rdev);
1562	else
1563		return -EINVAL;
1564}
1565
1566/**
1567 * regulator_get_voltage - get regulator output voltage
1568 * @regulator: regulator source
1569 *
1570 * This returns the current regulator voltage in uV.
1571 *
1572 * NOTE: If the regulator is disabled it will return the voltage value. This
1573 * function should not be used to determine regulator state.
1574 */
1575int regulator_get_voltage(struct regulator *regulator)
1576{
1577	int ret;
1578
1579	mutex_lock(&regulator->rdev->mutex);
1580
1581	ret = _regulator_get_voltage(regulator->rdev);
1582
1583	mutex_unlock(&regulator->rdev->mutex);
1584
1585	return ret;
1586}
1587EXPORT_SYMBOL_GPL(regulator_get_voltage);
1588
1589/**
1590 * regulator_set_current_limit - set regulator output current limit
1591 * @regulator: regulator source
1592 * @min_uA: Minimuum supported current in uA
1593 * @max_uA: Maximum supported current in uA
1594 *
1595 * Sets current sink to the desired output current. This can be set during
1596 * any regulator state. IOW, regulator can be disabled or enabled.
1597 *
1598 * If the regulator is enabled then the current will change to the new value
1599 * immediately otherwise if the regulator is disabled the regulator will
1600 * output at the new current when enabled.
1601 *
1602 * NOTE: Regulator system constraints must be set for this regulator before
1603 * calling this function otherwise this call will fail.
1604 */
1605int regulator_set_current_limit(struct regulator *regulator,
1606			       int min_uA, int max_uA)
1607{
1608	struct regulator_dev *rdev = regulator->rdev;
1609	int ret;
1610
1611	mutex_lock(&rdev->mutex);
1612
1613	/* sanity check */
1614	if (!rdev->desc->ops->set_current_limit) {
1615		ret = -EINVAL;
1616		goto out;
1617	}
1618
1619	/* constraints check */
1620	ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
1621	if (ret < 0)
1622		goto out;
1623
1624	ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
1625out:
1626	mutex_unlock(&rdev->mutex);
1627	return ret;
1628}
1629EXPORT_SYMBOL_GPL(regulator_set_current_limit);
1630
1631static int _regulator_get_current_limit(struct regulator_dev *rdev)
1632{
1633	int ret;
1634
1635	mutex_lock(&rdev->mutex);
1636
1637	/* sanity check */
1638	if (!rdev->desc->ops->get_current_limit) {
1639		ret = -EINVAL;
1640		goto out;
1641	}
1642
1643	ret = rdev->desc->ops->get_current_limit(rdev);
1644out:
1645	mutex_unlock(&rdev->mutex);
1646	return ret;
1647}
1648
1649/**
1650 * regulator_get_current_limit - get regulator output current
1651 * @regulator: regulator source
1652 *
1653 * This returns the current supplied by the specified current sink in uA.
1654 *
1655 * NOTE: If the regulator is disabled it will return the current value. This
1656 * function should not be used to determine regulator state.
1657 */
1658int regulator_get_current_limit(struct regulator *regulator)
1659{
1660	return _regulator_get_current_limit(regulator->rdev);
1661}
1662EXPORT_SYMBOL_GPL(regulator_get_current_limit);
1663
1664/**
1665 * regulator_set_mode - set regulator operating mode
1666 * @regulator: regulator source
1667 * @mode: operating mode - one of the REGULATOR_MODE constants
1668 *
1669 * Set regulator operating mode to increase regulator efficiency or improve
1670 * regulation performance.
1671 *
1672 * NOTE: Regulator system constraints must be set for this regulator before
1673 * calling this function otherwise this call will fail.
1674 */
1675int regulator_set_mode(struct regulator *regulator, unsigned int mode)
1676{
1677	struct regulator_dev *rdev = regulator->rdev;
1678	int ret;
1679
1680	mutex_lock(&rdev->mutex);
1681
1682	/* sanity check */
1683	if (!rdev->desc->ops->set_mode) {
1684		ret = -EINVAL;
1685		goto out;
1686	}
1687
1688	/* constraints check */
1689	ret = regulator_check_mode(rdev, mode);
1690	if (ret < 0)
1691		goto out;
1692
1693	ret = rdev->desc->ops->set_mode(rdev, mode);
1694out:
1695	mutex_unlock(&rdev->mutex);
1696	return ret;
1697}
1698EXPORT_SYMBOL_GPL(regulator_set_mode);
1699
1700static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
1701{
1702	int ret;
1703
1704	mutex_lock(&rdev->mutex);
1705
1706	/* sanity check */
1707	if (!rdev->desc->ops->get_mode) {
1708		ret = -EINVAL;
1709		goto out;
1710	}
1711
1712	ret = rdev->desc->ops->get_mode(rdev);
1713out:
1714	mutex_unlock(&rdev->mutex);
1715	return ret;
1716}
1717
1718/**
1719 * regulator_get_mode - get regulator operating mode
1720 * @regulator: regulator source
1721 *
1722 * Get the current regulator operating mode.
1723 */
1724unsigned int regulator_get_mode(struct regulator *regulator)
1725{
1726	return _regulator_get_mode(regulator->rdev);
1727}
1728EXPORT_SYMBOL_GPL(regulator_get_mode);
1729
1730/**
1731 * regulator_set_optimum_mode - set regulator optimum operating mode
1732 * @regulator: regulator source
1733 * @uA_load: load current
1734 *
1735 * Notifies the regulator core of a new device load. This is then used by
1736 * DRMS (if enabled by constraints) to set the most efficient regulator
1737 * operating mode for the new regulator loading.
1738 *
1739 * Consumer devices notify their supply regulator of the maximum power
1740 * they will require (can be taken from device datasheet in the power
1741 * consumption tables) when they change operational status and hence power
1742 * state. Examples of operational state changes that can affect power
1743 * consumption are :-
1744 *
1745 *    o Device is opened / closed.
1746 *    o Device I/O is about to begin or has just finished.
1747 *    o Device is idling in between work.
1748 *
1749 * This information is also exported via sysfs to userspace.
1750 *
1751 * DRMS will sum the total requested load on the regulator and change
1752 * to the most efficient operating mode if platform constraints allow.
1753 *
1754 * Returns the new regulator mode or error.
1755 */
1756int regulator_set_optimum_mode(struct regulator *regulator, int uA_load)
1757{
1758	struct regulator_dev *rdev = regulator->rdev;
1759	struct regulator *consumer;
1760	int ret, output_uV, input_uV, total_uA_load = 0;
1761	unsigned int mode;
1762
1763	mutex_lock(&rdev->mutex);
1764
1765	regulator->uA_load = uA_load;
1766	ret = regulator_check_drms(rdev);
1767	if (ret < 0)
1768		goto out;
1769	ret = -EINVAL;
1770
1771	/* sanity check */
1772	if (!rdev->desc->ops->get_optimum_mode)
1773		goto out;
1774
1775	/* get output voltage */
1776	output_uV = rdev->desc->ops->get_voltage(rdev);
1777	if (output_uV <= 0) {
1778		printk(KERN_ERR "%s: invalid output voltage found for %s\n",
1779			__func__, rdev->desc->name);
1780		goto out;
1781	}
1782
1783	/* get input voltage */
1784	if (rdev->supply && rdev->supply->desc->ops->get_voltage)
1785		input_uV = rdev->supply->desc->ops->get_voltage(rdev->supply);
1786	else
1787		input_uV = rdev->constraints->input_uV;
1788	if (input_uV <= 0) {
1789		printk(KERN_ERR "%s: invalid input voltage found for %s\n",
1790			__func__, rdev->desc->name);
1791		goto out;
1792	}
1793
1794	/* calc total requested load for this regulator */
1795	list_for_each_entry(consumer, &rdev->consumer_list, list)
1796	    total_uA_load += consumer->uA_load;
1797
1798	mode = rdev->desc->ops->get_optimum_mode(rdev,
1799						 input_uV, output_uV,
1800						 total_uA_load);
1801	ret = regulator_check_mode(rdev, mode);
1802	if (ret < 0) {
1803		printk(KERN_ERR "%s: failed to get optimum mode for %s @"
1804			" %d uA %d -> %d uV\n", __func__, rdev->desc->name,
1805			total_uA_load, input_uV, output_uV);
1806		goto out;
1807	}
1808
1809	ret = rdev->desc->ops->set_mode(rdev, mode);
1810	if (ret < 0) {
1811		printk(KERN_ERR "%s: failed to set optimum mode %x for %s\n",
1812			__func__, mode, rdev->desc->name);
1813		goto out;
1814	}
1815	ret = mode;
1816out:
1817	mutex_unlock(&rdev->mutex);
1818	return ret;
1819}
1820EXPORT_SYMBOL_GPL(regulator_set_optimum_mode);
1821
1822/**
1823 * regulator_register_notifier - register regulator event notifier
1824 * @regulator: regulator source
1825 * @nb: notifier block
1826 *
1827 * Register notifier block to receive regulator events.
1828 */
1829int regulator_register_notifier(struct regulator *regulator,
1830			      struct notifier_block *nb)
1831{
1832	return blocking_notifier_chain_register(&regulator->rdev->notifier,
1833						nb);
1834}
1835EXPORT_SYMBOL_GPL(regulator_register_notifier);
1836
1837/**
1838 * regulator_unregister_notifier - unregister regulator event notifier
1839 * @regulator: regulator source
1840 * @nb: notifier block
1841 *
1842 * Unregister regulator event notifier block.
1843 */
1844int regulator_unregister_notifier(struct regulator *regulator,
1845				struct notifier_block *nb)
1846{
1847	return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
1848						  nb);
1849}
1850EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
1851
1852/* notify regulator consumers and downstream regulator consumers.
1853 * Note mutex must be held by caller.
1854 */
1855static void _notifier_call_chain(struct regulator_dev *rdev,
1856				  unsigned long event, void *data)
1857{
1858	struct regulator_dev *_rdev;
1859
1860	/* call rdev chain first */
1861	blocking_notifier_call_chain(&rdev->notifier, event, NULL);
1862
1863	/* now notify regulator we supply */
1864	list_for_each_entry(_rdev, &rdev->supply_list, slist) {
1865	  mutex_lock(&_rdev->mutex);
1866	  _notifier_call_chain(_rdev, event, data);
1867	  mutex_unlock(&_rdev->mutex);
1868	}
1869}
1870
1871/**
1872 * regulator_bulk_get - get multiple regulator consumers
1873 *
1874 * @dev:           Device to supply
1875 * @num_consumers: Number of consumers to register
1876 * @consumers:     Configuration of consumers; clients are stored here.
1877 *
1878 * @return 0 on success, an errno on failure.
1879 *
1880 * This helper function allows drivers to get several regulator
1881 * consumers in one operation.  If any of the regulators cannot be
1882 * acquired then any regulators that were allocated will be freed
1883 * before returning to the caller.
1884 */
1885int regulator_bulk_get(struct device *dev, int num_consumers,
1886		       struct regulator_bulk_data *consumers)
1887{
1888	int i;
1889	int ret;
1890
1891	for (i = 0; i < num_consumers; i++)
1892		consumers[i].consumer = NULL;
1893
1894	for (i = 0; i < num_consumers; i++) {
1895		consumers[i].consumer = regulator_get(dev,
1896						      consumers[i].supply);
1897		if (IS_ERR(consumers[i].consumer)) {
1898			ret = PTR_ERR(consumers[i].consumer);
1899			dev_err(dev, "Failed to get supply '%s': %d\n",
1900				consumers[i].supply, ret);
1901			consumers[i].consumer = NULL;
1902			goto err;
1903		}
1904	}
1905
1906	return 0;
1907
1908err:
1909	for (i = 0; i < num_consumers && consumers[i].consumer; i++)
1910		regulator_put(consumers[i].consumer);
1911
1912	return ret;
1913}
1914EXPORT_SYMBOL_GPL(regulator_bulk_get);
1915
1916/**
1917 * regulator_bulk_enable - enable multiple regulator consumers
1918 *
1919 * @num_consumers: Number of consumers
1920 * @consumers:     Consumer data; clients are stored here.
1921 * @return         0 on success, an errno on failure
1922 *
1923 * This convenience API allows consumers to enable multiple regulator
1924 * clients in a single API call.  If any consumers cannot be enabled
1925 * then any others that were enabled will be disabled again prior to
1926 * return.
1927 */
1928int regulator_bulk_enable(int num_consumers,
1929			  struct regulator_bulk_data *consumers)
1930{
1931	int i;
1932	int ret;
1933
1934	for (i = 0; i < num_consumers; i++) {
1935		ret = regulator_enable(consumers[i].consumer);
1936		if (ret != 0)
1937			goto err;
1938	}
1939
1940	return 0;
1941
1942err:
1943	printk(KERN_ERR "Failed to enable %s: %d\n", consumers[i].supply, ret);
1944	for (i = 0; i < num_consumers; i++)
1945		regulator_disable(consumers[i].consumer);
1946
1947	return ret;
1948}
1949EXPORT_SYMBOL_GPL(regulator_bulk_enable);
1950
1951/**
1952 * regulator_bulk_disable - disable multiple regulator consumers
1953 *
1954 * @num_consumers: Number of consumers
1955 * @consumers:     Consumer data; clients are stored here.
1956 * @return         0 on success, an errno on failure
1957 *
1958 * This convenience API allows consumers to disable multiple regulator
1959 * clients in a single API call.  If any consumers cannot be enabled
1960 * then any others that were disabled will be disabled again prior to
1961 * return.
1962 */
1963int regulator_bulk_disable(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		ret = regulator_disable(consumers[i].consumer);
1971		if (ret != 0)
1972			goto err;
1973	}
1974
1975	return 0;
1976
1977err:
1978	printk(KERN_ERR "Failed to disable %s: %d\n", consumers[i].supply,
1979	       ret);
1980	for (i = 0; i < num_consumers; i++)
1981		regulator_enable(consumers[i].consumer);
1982
1983	return ret;
1984}
1985EXPORT_SYMBOL_GPL(regulator_bulk_disable);
1986
1987/**
1988 * regulator_bulk_free - free multiple regulator consumers
1989 *
1990 * @num_consumers: Number of consumers
1991 * @consumers:     Consumer data; clients are stored here.
1992 *
1993 * This convenience API allows consumers to free multiple regulator
1994 * clients in a single API call.
1995 */
1996void regulator_bulk_free(int num_consumers,
1997			 struct regulator_bulk_data *consumers)
1998{
1999	int i;
2000
2001	for (i = 0; i < num_consumers; i++) {
2002		regulator_put(consumers[i].consumer);
2003		consumers[i].consumer = NULL;
2004	}
2005}
2006EXPORT_SYMBOL_GPL(regulator_bulk_free);
2007
2008/**
2009 * regulator_notifier_call_chain - call regulator event notifier
2010 * @rdev: regulator source
2011 * @event: notifier block
2012 * @data: callback-specific data.
2013 *
2014 * Called by regulator drivers to notify clients a regulator event has
2015 * occurred. We also notify regulator clients downstream.
2016 * Note lock must be held by caller.
2017 */
2018int regulator_notifier_call_chain(struct regulator_dev *rdev,
2019				  unsigned long event, void *data)
2020{
2021	_notifier_call_chain(rdev, event, data);
2022	return NOTIFY_DONE;
2023
2024}
2025EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
2026
2027/**
2028 * regulator_mode_to_status - convert a regulator mode into a status
2029 *
2030 * @mode: Mode to convert
2031 *
2032 * Convert a regulator mode into a status.
2033 */
2034int regulator_mode_to_status(unsigned int mode)
2035{
2036	switch (mode) {
2037	case REGULATOR_MODE_FAST:
2038		return REGULATOR_STATUS_FAST;
2039	case REGULATOR_MODE_NORMAL:
2040		return REGULATOR_STATUS_NORMAL;
2041	case REGULATOR_MODE_IDLE:
2042		return REGULATOR_STATUS_IDLE;
2043	case REGULATOR_STATUS_STANDBY:
2044		return REGULATOR_STATUS_STANDBY;
2045	default:
2046		return 0;
2047	}
2048}
2049EXPORT_SYMBOL_GPL(regulator_mode_to_status);
2050
2051/*
2052 * To avoid cluttering sysfs (and memory) with useless state, only
2053 * create attributes that can be meaningfully displayed.
2054 */
2055static int add_regulator_attributes(struct regulator_dev *rdev)
2056{
2057	struct device		*dev = &rdev->dev;
2058	struct regulator_ops	*ops = rdev->desc->ops;
2059	int			status = 0;
2060
2061	/* some attributes need specific methods to be displayed */
2062	if (ops->get_voltage) {
2063		status = device_create_file(dev, &dev_attr_microvolts);
2064		if (status < 0)
2065			return status;
2066	}
2067	if (ops->get_current_limit) {
2068		status = device_create_file(dev, &dev_attr_microamps);
2069		if (status < 0)
2070			return status;
2071	}
2072	if (ops->get_mode) {
2073		status = device_create_file(dev, &dev_attr_opmode);
2074		if (status < 0)
2075			return status;
2076	}
2077	if (ops->is_enabled) {
2078		status = device_create_file(dev, &dev_attr_state);
2079		if (status < 0)
2080			return status;
2081	}
2082	if (ops->get_status) {
2083		status = device_create_file(dev, &dev_attr_status);
2084		if (status < 0)
2085			return status;
2086	}
2087
2088	/* some attributes are type-specific */
2089	if (rdev->desc->type == REGULATOR_CURRENT) {
2090		status = device_create_file(dev, &dev_attr_requested_microamps);
2091		if (status < 0)
2092			return status;
2093	}
2094
2095	/* all the other attributes exist to support constraints;
2096	 * don't show them if there are no constraints, or if the
2097	 * relevant supporting methods are missing.
2098	 */
2099	if (!rdev->constraints)
2100		return status;
2101
2102	/* constraints need specific supporting methods */
2103	if (ops->set_voltage) {
2104		status = device_create_file(dev, &dev_attr_min_microvolts);
2105		if (status < 0)
2106			return status;
2107		status = device_create_file(dev, &dev_attr_max_microvolts);
2108		if (status < 0)
2109			return status;
2110	}
2111	if (ops->set_current_limit) {
2112		status = device_create_file(dev, &dev_attr_min_microamps);
2113		if (status < 0)
2114			return status;
2115		status = device_create_file(dev, &dev_attr_max_microamps);
2116		if (status < 0)
2117			return status;
2118	}
2119
2120	/* suspend mode constraints need multiple supporting methods */
2121	if (!(ops->set_suspend_enable && ops->set_suspend_disable))
2122		return status;
2123
2124	status = device_create_file(dev, &dev_attr_suspend_standby_state);
2125	if (status < 0)
2126		return status;
2127	status = device_create_file(dev, &dev_attr_suspend_mem_state);
2128	if (status < 0)
2129		return status;
2130	status = device_create_file(dev, &dev_attr_suspend_disk_state);
2131	if (status < 0)
2132		return status;
2133
2134	if (ops->set_suspend_voltage) {
2135		status = device_create_file(dev,
2136				&dev_attr_suspend_standby_microvolts);
2137		if (status < 0)
2138			return status;
2139		status = device_create_file(dev,
2140				&dev_attr_suspend_mem_microvolts);
2141		if (status < 0)
2142			return status;
2143		status = device_create_file(dev,
2144				&dev_attr_suspend_disk_microvolts);
2145		if (status < 0)
2146			return status;
2147	}
2148
2149	if (ops->set_suspend_mode) {
2150		status = device_create_file(dev,
2151				&dev_attr_suspend_standby_mode);
2152		if (status < 0)
2153			return status;
2154		status = device_create_file(dev,
2155				&dev_attr_suspend_mem_mode);
2156		if (status < 0)
2157			return status;
2158		status = device_create_file(dev,
2159				&dev_attr_suspend_disk_mode);
2160		if (status < 0)
2161			return status;
2162	}
2163
2164	return status;
2165}
2166
2167/**
2168 * regulator_register - register regulator
2169 * @regulator_desc: regulator to register
2170 * @dev: struct device for the regulator
2171 * @init_data: platform provided init data, passed through by driver
2172 * @driver_data: private regulator data
2173 *
2174 * Called by regulator drivers to register a regulator.
2175 * Returns 0 on success.
2176 */
2177struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc,
2178	struct device *dev, struct regulator_init_data *init_data,
2179	void *driver_data)
2180{
2181	static atomic_t regulator_no = ATOMIC_INIT(0);
2182	struct regulator_dev *rdev;
2183	int ret, i;
2184
2185	if (regulator_desc == NULL)
2186		return ERR_PTR(-EINVAL);
2187
2188	if (regulator_desc->name == NULL || regulator_desc->ops == NULL)
2189		return ERR_PTR(-EINVAL);
2190
2191	if (regulator_desc->type != REGULATOR_VOLTAGE &&
2192	    regulator_desc->type != REGULATOR_CURRENT)
2193		return ERR_PTR(-EINVAL);
2194
2195	if (!init_data)
2196		return ERR_PTR(-EINVAL);
2197
2198	rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
2199	if (rdev == NULL)
2200		return ERR_PTR(-ENOMEM);
2201
2202	mutex_lock(&regulator_list_mutex);
2203
2204	mutex_init(&rdev->mutex);
2205	rdev->reg_data = driver_data;
2206	rdev->owner = regulator_desc->owner;
2207	rdev->desc = regulator_desc;
2208	INIT_LIST_HEAD(&rdev->consumer_list);
2209	INIT_LIST_HEAD(&rdev->supply_list);
2210	INIT_LIST_HEAD(&rdev->list);
2211	INIT_LIST_HEAD(&rdev->slist);
2212	BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
2213
2214	/* preform any regulator specific init */
2215	if (init_data->regulator_init) {
2216		ret = init_data->regulator_init(rdev->reg_data);
2217		if (ret < 0)
2218			goto clean;
2219	}
2220
2221	/* register with sysfs */
2222	rdev->dev.class = &regulator_class;
2223	rdev->dev.parent = dev;
2224	dev_set_name(&rdev->dev, "regulator.%d",
2225		     atomic_inc_return(&regulator_no) - 1);
2226	ret = device_register(&rdev->dev);
2227	if (ret != 0)
2228		goto clean;
2229
2230	dev_set_drvdata(&rdev->dev, rdev);
2231
2232	/* set regulator constraints */
2233	ret = set_machine_constraints(rdev, &init_data->constraints);
2234	if (ret < 0)
2235		goto scrub;
2236
2237	/* add attributes supported by this regulator */
2238	ret = add_regulator_attributes(rdev);
2239	if (ret < 0)
2240		goto scrub;
2241
2242	/* set supply regulator if it exists */
2243	if (init_data->supply_regulator_dev) {
2244		ret = set_supply(rdev,
2245			dev_get_drvdata(init_data->supply_regulator_dev));
2246		if (ret < 0)
2247			goto scrub;
2248	}
2249
2250	/* add consumers devices */
2251	for (i = 0; i < init_data->num_consumer_supplies; i++) {
2252		ret = set_consumer_device_supply(rdev,
2253			init_data->consumer_supplies[i].dev,
2254			init_data->consumer_supplies[i].dev_name,
2255			init_data->consumer_supplies[i].supply);
2256		if (ret < 0) {
2257			for (--i; i >= 0; i--)
2258				unset_consumer_device_supply(rdev,
2259				    init_data->consumer_supplies[i].dev_name,
2260				    init_data->consumer_supplies[i].dev);
2261			goto scrub;
2262		}
2263	}
2264
2265	list_add(&rdev->list, &regulator_list);
2266out:
2267	mutex_unlock(&regulator_list_mutex);
2268	return rdev;
2269
2270scrub:
2271	device_unregister(&rdev->dev);
2272	/* device core frees rdev */
2273	rdev = ERR_PTR(ret);
2274	goto out;
2275
2276clean:
2277	kfree(rdev);
2278	rdev = ERR_PTR(ret);
2279	goto out;
2280}
2281EXPORT_SYMBOL_GPL(regulator_register);
2282
2283/**
2284 * regulator_unregister - unregister regulator
2285 * @rdev: regulator to unregister
2286 *
2287 * Called by regulator drivers to unregister a regulator.
2288 */
2289void regulator_unregister(struct regulator_dev *rdev)
2290{
2291	if (rdev == NULL)
2292		return;
2293
2294	mutex_lock(&regulator_list_mutex);
2295	WARN_ON(rdev->open_count);
2296	unset_regulator_supplies(rdev);
2297	list_del(&rdev->list);
2298	if (rdev->supply)
2299		sysfs_remove_link(&rdev->dev.kobj, "supply");
2300	device_unregister(&rdev->dev);
2301	mutex_unlock(&regulator_list_mutex);
2302}
2303EXPORT_SYMBOL_GPL(regulator_unregister);
2304
2305/**
2306 * regulator_suspend_prepare - prepare regulators for system wide suspend
2307 * @state: system suspend state
2308 *
2309 * Configure each regulator with it's suspend operating parameters for state.
2310 * This will usually be called by machine suspend code prior to supending.
2311 */
2312int regulator_suspend_prepare(suspend_state_t state)
2313{
2314	struct regulator_dev *rdev;
2315	int ret = 0;
2316
2317	/* ON is handled by regulator active state */
2318	if (state == PM_SUSPEND_ON)
2319		return -EINVAL;
2320
2321	mutex_lock(&regulator_list_mutex);
2322	list_for_each_entry(rdev, &regulator_list, list) {
2323
2324		mutex_lock(&rdev->mutex);
2325		ret = suspend_prepare(rdev, state);
2326		mutex_unlock(&rdev->mutex);
2327
2328		if (ret < 0) {
2329			printk(KERN_ERR "%s: failed to prepare %s\n",
2330				__func__, rdev->desc->name);
2331			goto out;
2332		}
2333	}
2334out:
2335	mutex_unlock(&regulator_list_mutex);
2336	return ret;
2337}
2338EXPORT_SYMBOL_GPL(regulator_suspend_prepare);
2339
2340/**
2341 * regulator_has_full_constraints - the system has fully specified constraints
2342 *
2343 * Calling this function will cause the regulator API to disable all
2344 * regulators which have a zero use count and don't have an always_on
2345 * constraint in a late_initcall.
2346 *
2347 * The intention is that this will become the default behaviour in a
2348 * future kernel release so users are encouraged to use this facility
2349 * now.
2350 */
2351void regulator_has_full_constraints(void)
2352{
2353	has_full_constraints = 1;
2354}
2355EXPORT_SYMBOL_GPL(regulator_has_full_constraints);
2356
2357/**
2358 * rdev_get_drvdata - get rdev regulator driver data
2359 * @rdev: regulator
2360 *
2361 * Get rdev regulator driver private data. This call can be used in the
2362 * regulator driver context.
2363 */
2364void *rdev_get_drvdata(struct regulator_dev *rdev)
2365{
2366	return rdev->reg_data;
2367}
2368EXPORT_SYMBOL_GPL(rdev_get_drvdata);
2369
2370/**
2371 * regulator_get_drvdata - get regulator driver data
2372 * @regulator: regulator
2373 *
2374 * Get regulator driver private data. This call can be used in the consumer
2375 * driver context when non API regulator specific functions need to be called.
2376 */
2377void *regulator_get_drvdata(struct regulator *regulator)
2378{
2379	return regulator->rdev->reg_data;
2380}
2381EXPORT_SYMBOL_GPL(regulator_get_drvdata);
2382
2383/**
2384 * regulator_set_drvdata - set regulator driver data
2385 * @regulator: regulator
2386 * @data: data
2387 */
2388void regulator_set_drvdata(struct regulator *regulator, void *data)
2389{
2390	regulator->rdev->reg_data = data;
2391}
2392EXPORT_SYMBOL_GPL(regulator_set_drvdata);
2393
2394/**
2395 * regulator_get_id - get regulator ID
2396 * @rdev: regulator
2397 */
2398int rdev_get_id(struct regulator_dev *rdev)
2399{
2400	return rdev->desc->id;
2401}
2402EXPORT_SYMBOL_GPL(rdev_get_id);
2403
2404struct device *rdev_get_dev(struct regulator_dev *rdev)
2405{
2406	return &rdev->dev;
2407}
2408EXPORT_SYMBOL_GPL(rdev_get_dev);
2409
2410void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
2411{
2412	return reg_init_data->driver_data;
2413}
2414EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
2415
2416static int __init regulator_init(void)
2417{
2418	printk(KERN_INFO "regulator: core version %s\n", REGULATOR_VERSION);
2419	return class_register(&regulator_class);
2420}
2421
2422/* init early to allow our consumers to complete system booting */
2423core_initcall(regulator_init);
2424
2425static int __init regulator_init_complete(void)
2426{
2427	struct regulator_dev *rdev;
2428	struct regulator_ops *ops;
2429	struct regulation_constraints *c;
2430	int enabled, ret;
2431	const char *name;
2432
2433	mutex_lock(&regulator_list_mutex);
2434
2435	/* If we have a full configuration then disable any regulators
2436	 * which are not in use or always_on.  This will become the
2437	 * default behaviour in the future.
2438	 */
2439	list_for_each_entry(rdev, &regulator_list, list) {
2440		ops = rdev->desc->ops;
2441		c = rdev->constraints;
2442
2443		if (c && c->name)
2444			name = c->name;
2445		else if (rdev->desc->name)
2446			name = rdev->desc->name;
2447		else
2448			name = "regulator";
2449
2450		if (!ops->disable || (c && c->always_on))
2451			continue;
2452
2453		mutex_lock(&rdev->mutex);
2454
2455		if (rdev->use_count)
2456			goto unlock;
2457
2458		/* If we can't read the status assume it's on. */
2459		if (ops->is_enabled)
2460			enabled = ops->is_enabled(rdev);
2461		else
2462			enabled = 1;
2463
2464		if (!enabled)
2465			goto unlock;
2466
2467		if (has_full_constraints) {
2468			/* We log since this may kill the system if it
2469			 * goes wrong. */
2470			printk(KERN_INFO "%s: disabling %s\n",
2471			       __func__, name);
2472			ret = ops->disable(rdev);
2473			if (ret != 0) {
2474				printk(KERN_ERR
2475				       "%s: couldn't disable %s: %d\n",
2476				       __func__, name, ret);
2477			}
2478		} else {
2479			/* The intention is that in future we will
2480			 * assume that full constraints are provided
2481			 * so warn even if we aren't going to do
2482			 * anything here.
2483			 */
2484			printk(KERN_WARNING
2485			       "%s: incomplete constraints, leaving %s on\n",
2486			       __func__, name);
2487		}
2488
2489unlock:
2490		mutex_unlock(&rdev->mutex);
2491	}
2492
2493	mutex_unlock(&regulator_list_mutex);
2494
2495	return 0;
2496}
2497late_initcall(regulator_init_complete);
2498