xref: /linux/drivers/regulator/core.c (revision a5766f11cfd3a0c03450d99c8fe548c2940be884)
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 
28 static DEFINE_MUTEX(regulator_list_mutex);
29 static LIST_HEAD(regulator_list);
30 static LIST_HEAD(regulator_map_list);
31 
32 /**
33  * struct regulator_dev
34  *
35  * Voltage / Current regulator class device. One for each regulator.
36  */
37 struct regulator_dev {
38 	struct regulator_desc *desc;
39 	int use_count;
40 
41 	/* lists we belong to */
42 	struct list_head list; /* list of all regulators */
43 	struct list_head slist; /* list of supplied regulators */
44 
45 	/* lists we own */
46 	struct list_head consumer_list; /* consumers we supply */
47 	struct list_head supply_list; /* regulators we supply */
48 
49 	struct blocking_notifier_head notifier;
50 	struct mutex mutex; /* consumer lock */
51 	struct module *owner;
52 	struct device dev;
53 	struct regulation_constraints *constraints;
54 	struct regulator_dev *supply;	/* for tree */
55 
56 	void *reg_data;		/* regulator_dev data */
57 };
58 
59 /**
60  * struct regulator_map
61  *
62  * Used to provide symbolic supply names to devices.
63  */
64 struct regulator_map {
65 	struct list_head list;
66 	struct device *dev;
67 	const char *supply;
68 	struct regulator_dev *regulator;
69 };
70 
71 /*
72  * struct regulator
73  *
74  * One for each consumer device.
75  */
76 struct regulator {
77 	struct device *dev;
78 	struct list_head list;
79 	int uA_load;
80 	int min_uV;
81 	int max_uV;
82 	int enabled; /* client has called enabled */
83 	char *supply_name;
84 	struct device_attribute dev_attr;
85 	struct regulator_dev *rdev;
86 };
87 
88 static int _regulator_is_enabled(struct regulator_dev *rdev);
89 static int _regulator_disable(struct regulator_dev *rdev);
90 static int _regulator_get_voltage(struct regulator_dev *rdev);
91 static int _regulator_get_current_limit(struct regulator_dev *rdev);
92 static unsigned int _regulator_get_mode(struct regulator_dev *rdev);
93 static void _notifier_call_chain(struct regulator_dev *rdev,
94 				  unsigned long event, void *data);
95 
96 /* gets the regulator for a given consumer device */
97 static struct regulator *get_device_regulator(struct device *dev)
98 {
99 	struct regulator *regulator = NULL;
100 	struct regulator_dev *rdev;
101 
102 	mutex_lock(&regulator_list_mutex);
103 	list_for_each_entry(rdev, &regulator_list, list) {
104 		mutex_lock(&rdev->mutex);
105 		list_for_each_entry(regulator, &rdev->consumer_list, list) {
106 			if (regulator->dev == dev) {
107 				mutex_unlock(&rdev->mutex);
108 				mutex_unlock(&regulator_list_mutex);
109 				return regulator;
110 			}
111 		}
112 		mutex_unlock(&rdev->mutex);
113 	}
114 	mutex_unlock(&regulator_list_mutex);
115 	return NULL;
116 }
117 
118 /* Platform voltage constraint check */
119 static int regulator_check_voltage(struct regulator_dev *rdev,
120 				   int *min_uV, int *max_uV)
121 {
122 	BUG_ON(*min_uV > *max_uV);
123 
124 	if (!rdev->constraints) {
125 		printk(KERN_ERR "%s: no constraints for %s\n", __func__,
126 		       rdev->desc->name);
127 		return -ENODEV;
128 	}
129 	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
130 		printk(KERN_ERR "%s: operation not allowed for %s\n",
131 		       __func__, rdev->desc->name);
132 		return -EPERM;
133 	}
134 
135 	if (*max_uV > rdev->constraints->max_uV)
136 		*max_uV = rdev->constraints->max_uV;
137 	if (*min_uV < rdev->constraints->min_uV)
138 		*min_uV = rdev->constraints->min_uV;
139 
140 	if (*min_uV > *max_uV)
141 		return -EINVAL;
142 
143 	return 0;
144 }
145 
146 /* current constraint check */
147 static int regulator_check_current_limit(struct regulator_dev *rdev,
148 					int *min_uA, int *max_uA)
149 {
150 	BUG_ON(*min_uA > *max_uA);
151 
152 	if (!rdev->constraints) {
153 		printk(KERN_ERR "%s: no constraints for %s\n", __func__,
154 		       rdev->desc->name);
155 		return -ENODEV;
156 	}
157 	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_CURRENT)) {
158 		printk(KERN_ERR "%s: operation not allowed for %s\n",
159 		       __func__, rdev->desc->name);
160 		return -EPERM;
161 	}
162 
163 	if (*max_uA > rdev->constraints->max_uA)
164 		*max_uA = rdev->constraints->max_uA;
165 	if (*min_uA < rdev->constraints->min_uA)
166 		*min_uA = rdev->constraints->min_uA;
167 
168 	if (*min_uA > *max_uA)
169 		return -EINVAL;
170 
171 	return 0;
172 }
173 
174 /* operating mode constraint check */
175 static int regulator_check_mode(struct regulator_dev *rdev, int mode)
176 {
177 	if (!rdev->constraints) {
178 		printk(KERN_ERR "%s: no constraints for %s\n", __func__,
179 		       rdev->desc->name);
180 		return -ENODEV;
181 	}
182 	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_MODE)) {
183 		printk(KERN_ERR "%s: operation not allowed for %s\n",
184 		       __func__, rdev->desc->name);
185 		return -EPERM;
186 	}
187 	if (!(rdev->constraints->valid_modes_mask & mode)) {
188 		printk(KERN_ERR "%s: invalid mode %x for %s\n",
189 		       __func__, mode, rdev->desc->name);
190 		return -EINVAL;
191 	}
192 	return 0;
193 }
194 
195 /* dynamic regulator mode switching constraint check */
196 static int regulator_check_drms(struct regulator_dev *rdev)
197 {
198 	if (!rdev->constraints) {
199 		printk(KERN_ERR "%s: no constraints for %s\n", __func__,
200 		       rdev->desc->name);
201 		return -ENODEV;
202 	}
203 	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS)) {
204 		printk(KERN_ERR "%s: operation not allowed for %s\n",
205 		       __func__, rdev->desc->name);
206 		return -EPERM;
207 	}
208 	return 0;
209 }
210 
211 static ssize_t device_requested_uA_show(struct device *dev,
212 			     struct device_attribute *attr, char *buf)
213 {
214 	struct regulator *regulator;
215 
216 	regulator = get_device_regulator(dev);
217 	if (regulator == NULL)
218 		return 0;
219 
220 	return sprintf(buf, "%d\n", regulator->uA_load);
221 }
222 
223 static ssize_t regulator_uV_show(struct device *dev,
224 				struct device_attribute *attr, char *buf)
225 {
226 	struct regulator_dev *rdev = dev_get_drvdata(dev);
227 	ssize_t ret;
228 
229 	mutex_lock(&rdev->mutex);
230 	ret = sprintf(buf, "%d\n", _regulator_get_voltage(rdev));
231 	mutex_unlock(&rdev->mutex);
232 
233 	return ret;
234 }
235 
236 static ssize_t regulator_uA_show(struct device *dev,
237 				struct device_attribute *attr, char *buf)
238 {
239 	struct regulator_dev *rdev = dev_get_drvdata(dev);
240 
241 	return sprintf(buf, "%d\n", _regulator_get_current_limit(rdev));
242 }
243 
244 static ssize_t regulator_opmode_show(struct device *dev,
245 				    struct device_attribute *attr, char *buf)
246 {
247 	struct regulator_dev *rdev = dev_get_drvdata(dev);
248 	int mode = _regulator_get_mode(rdev);
249 
250 	switch (mode) {
251 	case REGULATOR_MODE_FAST:
252 		return sprintf(buf, "fast\n");
253 	case REGULATOR_MODE_NORMAL:
254 		return sprintf(buf, "normal\n");
255 	case REGULATOR_MODE_IDLE:
256 		return sprintf(buf, "idle\n");
257 	case REGULATOR_MODE_STANDBY:
258 		return sprintf(buf, "standby\n");
259 	}
260 	return sprintf(buf, "unknown\n");
261 }
262 
263 static ssize_t regulator_state_show(struct device *dev,
264 				   struct device_attribute *attr, char *buf)
265 {
266 	struct regulator_dev *rdev = dev_get_drvdata(dev);
267 	int state = _regulator_is_enabled(rdev);
268 
269 	if (state > 0)
270 		return sprintf(buf, "enabled\n");
271 	else if (state == 0)
272 		return sprintf(buf, "disabled\n");
273 	else
274 		return sprintf(buf, "unknown\n");
275 }
276 
277 static ssize_t regulator_min_uA_show(struct device *dev,
278 				    struct device_attribute *attr, char *buf)
279 {
280 	struct regulator_dev *rdev = dev_get_drvdata(dev);
281 
282 	if (!rdev->constraints)
283 		return sprintf(buf, "constraint not defined\n");
284 
285 	return sprintf(buf, "%d\n", rdev->constraints->min_uA);
286 }
287 
288 static ssize_t regulator_max_uA_show(struct device *dev,
289 				    struct device_attribute *attr, char *buf)
290 {
291 	struct regulator_dev *rdev = dev_get_drvdata(dev);
292 
293 	if (!rdev->constraints)
294 		return sprintf(buf, "constraint not defined\n");
295 
296 	return sprintf(buf, "%d\n", rdev->constraints->max_uA);
297 }
298 
299 static ssize_t regulator_min_uV_show(struct device *dev,
300 				    struct device_attribute *attr, char *buf)
301 {
302 	struct regulator_dev *rdev = dev_get_drvdata(dev);
303 
304 	if (!rdev->constraints)
305 		return sprintf(buf, "constraint not defined\n");
306 
307 	return sprintf(buf, "%d\n", rdev->constraints->min_uV);
308 }
309 
310 static ssize_t regulator_max_uV_show(struct device *dev,
311 				    struct device_attribute *attr, char *buf)
312 {
313 	struct regulator_dev *rdev = dev_get_drvdata(dev);
314 
315 	if (!rdev->constraints)
316 		return sprintf(buf, "constraint not defined\n");
317 
318 	return sprintf(buf, "%d\n", rdev->constraints->max_uV);
319 }
320 
321 static ssize_t regulator_total_uA_show(struct device *dev,
322 				      struct device_attribute *attr, char *buf)
323 {
324 	struct regulator_dev *rdev = dev_get_drvdata(dev);
325 	struct regulator *regulator;
326 	int uA = 0;
327 
328 	mutex_lock(&rdev->mutex);
329 	list_for_each_entry(regulator, &rdev->consumer_list, list)
330 	    uA += regulator->uA_load;
331 	mutex_unlock(&rdev->mutex);
332 	return sprintf(buf, "%d\n", uA);
333 }
334 
335 static ssize_t regulator_num_users_show(struct device *dev,
336 				      struct device_attribute *attr, char *buf)
337 {
338 	struct regulator_dev *rdev = dev_get_drvdata(dev);
339 	return sprintf(buf, "%d\n", rdev->use_count);
340 }
341 
342 static ssize_t regulator_type_show(struct device *dev,
343 				  struct device_attribute *attr, char *buf)
344 {
345 	struct regulator_dev *rdev = dev_get_drvdata(dev);
346 
347 	switch (rdev->desc->type) {
348 	case REGULATOR_VOLTAGE:
349 		return sprintf(buf, "voltage\n");
350 	case REGULATOR_CURRENT:
351 		return sprintf(buf, "current\n");
352 	}
353 	return sprintf(buf, "unknown\n");
354 }
355 
356 static ssize_t regulator_suspend_mem_uV_show(struct device *dev,
357 				struct device_attribute *attr, char *buf)
358 {
359 	struct regulator_dev *rdev = dev_get_drvdata(dev);
360 
361 	if (!rdev->constraints)
362 		return sprintf(buf, "not defined\n");
363 	return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
364 }
365 
366 static ssize_t regulator_suspend_disk_uV_show(struct device *dev,
367 				struct device_attribute *attr, char *buf)
368 {
369 	struct regulator_dev *rdev = dev_get_drvdata(dev);
370 
371 	if (!rdev->constraints)
372 		return sprintf(buf, "not defined\n");
373 	return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
374 }
375 
376 static ssize_t regulator_suspend_standby_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, "not defined\n");
383 	return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
384 }
385 
386 static ssize_t suspend_opmode_show(struct regulator_dev *rdev,
387 	unsigned int mode, char *buf)
388 {
389 	switch (mode) {
390 	case REGULATOR_MODE_FAST:
391 		return sprintf(buf, "fast\n");
392 	case REGULATOR_MODE_NORMAL:
393 		return sprintf(buf, "normal\n");
394 	case REGULATOR_MODE_IDLE:
395 		return sprintf(buf, "idle\n");
396 	case REGULATOR_MODE_STANDBY:
397 		return sprintf(buf, "standby\n");
398 	}
399 	return sprintf(buf, "unknown\n");
400 }
401 
402 static ssize_t regulator_suspend_mem_mode_show(struct device *dev,
403 				struct device_attribute *attr, char *buf)
404 {
405 	struct regulator_dev *rdev = dev_get_drvdata(dev);
406 
407 	if (!rdev->constraints)
408 		return sprintf(buf, "not defined\n");
409 	return suspend_opmode_show(rdev,
410 		rdev->constraints->state_mem.mode, buf);
411 }
412 
413 static ssize_t regulator_suspend_disk_mode_show(struct device *dev,
414 				struct device_attribute *attr, char *buf)
415 {
416 	struct regulator_dev *rdev = dev_get_drvdata(dev);
417 
418 	if (!rdev->constraints)
419 		return sprintf(buf, "not defined\n");
420 	return suspend_opmode_show(rdev,
421 		rdev->constraints->state_disk.mode, buf);
422 }
423 
424 static ssize_t regulator_suspend_standby_mode_show(struct device *dev,
425 				struct device_attribute *attr, char *buf)
426 {
427 	struct regulator_dev *rdev = dev_get_drvdata(dev);
428 
429 	if (!rdev->constraints)
430 		return sprintf(buf, "not defined\n");
431 	return suspend_opmode_show(rdev,
432 		rdev->constraints->state_standby.mode, buf);
433 }
434 
435 static ssize_t regulator_suspend_mem_state_show(struct device *dev,
436 				   struct device_attribute *attr, char *buf)
437 {
438 	struct regulator_dev *rdev = dev_get_drvdata(dev);
439 
440 	if (!rdev->constraints)
441 		return sprintf(buf, "not defined\n");
442 
443 	if (rdev->constraints->state_mem.enabled)
444 		return sprintf(buf, "enabled\n");
445 	else
446 		return sprintf(buf, "disabled\n");
447 }
448 
449 static ssize_t regulator_suspend_disk_state_show(struct device *dev,
450 				   struct device_attribute *attr, char *buf)
451 {
452 	struct regulator_dev *rdev = dev_get_drvdata(dev);
453 
454 	if (!rdev->constraints)
455 		return sprintf(buf, "not defined\n");
456 
457 	if (rdev->constraints->state_disk.enabled)
458 		return sprintf(buf, "enabled\n");
459 	else
460 		return sprintf(buf, "disabled\n");
461 }
462 
463 static ssize_t regulator_suspend_standby_state_show(struct device *dev,
464 				   struct device_attribute *attr, char *buf)
465 {
466 	struct regulator_dev *rdev = dev_get_drvdata(dev);
467 
468 	if (!rdev->constraints)
469 		return sprintf(buf, "not defined\n");
470 
471 	if (rdev->constraints->state_standby.enabled)
472 		return sprintf(buf, "enabled\n");
473 	else
474 		return sprintf(buf, "disabled\n");
475 }
476 static struct device_attribute regulator_dev_attrs[] = {
477 	__ATTR(microvolts, 0444, regulator_uV_show, NULL),
478 	__ATTR(microamps, 0444, regulator_uA_show, NULL),
479 	__ATTR(opmode, 0444, regulator_opmode_show, NULL),
480 	__ATTR(state, 0444, regulator_state_show, NULL),
481 	__ATTR(min_microvolts, 0444, regulator_min_uV_show, NULL),
482 	__ATTR(min_microamps, 0444, regulator_min_uA_show, NULL),
483 	__ATTR(max_microvolts, 0444, regulator_max_uV_show, NULL),
484 	__ATTR(max_microamps, 0444, regulator_max_uA_show, NULL),
485 	__ATTR(requested_microamps, 0444, regulator_total_uA_show, NULL),
486 	__ATTR(num_users, 0444, regulator_num_users_show, NULL),
487 	__ATTR(type, 0444, regulator_type_show, NULL),
488 	__ATTR(suspend_mem_microvolts, 0444,
489 		regulator_suspend_mem_uV_show, NULL),
490 	__ATTR(suspend_disk_microvolts, 0444,
491 		regulator_suspend_disk_uV_show, NULL),
492 	__ATTR(suspend_standby_microvolts, 0444,
493 		regulator_suspend_standby_uV_show, NULL),
494 	__ATTR(suspend_mem_mode, 0444,
495 		regulator_suspend_mem_mode_show, NULL),
496 	__ATTR(suspend_disk_mode, 0444,
497 		regulator_suspend_disk_mode_show, NULL),
498 	__ATTR(suspend_standby_mode, 0444,
499 		regulator_suspend_standby_mode_show, NULL),
500 	__ATTR(suspend_mem_state, 0444,
501 		regulator_suspend_mem_state_show, NULL),
502 	__ATTR(suspend_disk_state, 0444,
503 		regulator_suspend_disk_state_show, NULL),
504 	__ATTR(suspend_standby_state, 0444,
505 		regulator_suspend_standby_state_show, NULL),
506 	__ATTR_NULL,
507 };
508 
509 static void regulator_dev_release(struct device *dev)
510 {
511 	struct regulator_dev *rdev = dev_get_drvdata(dev);
512 	kfree(rdev);
513 }
514 
515 static struct class regulator_class = {
516 	.name = "regulator",
517 	.dev_release = regulator_dev_release,
518 	.dev_attrs = regulator_dev_attrs,
519 };
520 
521 /* Calculate the new optimum regulator operating mode based on the new total
522  * consumer load. All locks held by caller */
523 static void drms_uA_update(struct regulator_dev *rdev)
524 {
525 	struct regulator *sibling;
526 	int current_uA = 0, output_uV, input_uV, err;
527 	unsigned int mode;
528 
529 	err = regulator_check_drms(rdev);
530 	if (err < 0 || !rdev->desc->ops->get_optimum_mode ||
531 	    !rdev->desc->ops->get_voltage || !rdev->desc->ops->set_mode);
532 	return;
533 
534 	/* get output voltage */
535 	output_uV = rdev->desc->ops->get_voltage(rdev);
536 	if (output_uV <= 0)
537 		return;
538 
539 	/* get input voltage */
540 	if (rdev->supply && rdev->supply->desc->ops->get_voltage)
541 		input_uV = rdev->supply->desc->ops->get_voltage(rdev->supply);
542 	else
543 		input_uV = rdev->constraints->input_uV;
544 	if (input_uV <= 0)
545 		return;
546 
547 	/* calc total requested load */
548 	list_for_each_entry(sibling, &rdev->consumer_list, list)
549 	    current_uA += sibling->uA_load;
550 
551 	/* now get the optimum mode for our new total regulator load */
552 	mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
553 						  output_uV, current_uA);
554 
555 	/* check the new mode is allowed */
556 	err = regulator_check_mode(rdev, mode);
557 	if (err == 0)
558 		rdev->desc->ops->set_mode(rdev, mode);
559 }
560 
561 static int suspend_set_state(struct regulator_dev *rdev,
562 	struct regulator_state *rstate)
563 {
564 	int ret = 0;
565 
566 	/* enable & disable are mandatory for suspend control */
567 	if (!rdev->desc->ops->set_suspend_enable ||
568 		!rdev->desc->ops->set_suspend_disable) {
569 		printk(KERN_ERR "%s: no way to set suspend state\n",
570 			__func__);
571 		return -EINVAL;
572 	}
573 
574 	if (rstate->enabled)
575 		ret = rdev->desc->ops->set_suspend_enable(rdev);
576 	else
577 		ret = rdev->desc->ops->set_suspend_disable(rdev);
578 	if (ret < 0) {
579 		printk(KERN_ERR "%s: failed to enabled/disable\n", __func__);
580 		return ret;
581 	}
582 
583 	if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
584 		ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
585 		if (ret < 0) {
586 			printk(KERN_ERR "%s: failed to set voltage\n",
587 				__func__);
588 			return ret;
589 		}
590 	}
591 
592 	if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
593 		ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
594 		if (ret < 0) {
595 			printk(KERN_ERR "%s: failed to set mode\n", __func__);
596 			return ret;
597 		}
598 	}
599 	return ret;
600 }
601 
602 /* locks held by caller */
603 static int suspend_prepare(struct regulator_dev *rdev, suspend_state_t state)
604 {
605 	if (!rdev->constraints)
606 		return -EINVAL;
607 
608 	switch (state) {
609 	case PM_SUSPEND_STANDBY:
610 		return suspend_set_state(rdev,
611 			&rdev->constraints->state_standby);
612 	case PM_SUSPEND_MEM:
613 		return suspend_set_state(rdev,
614 			&rdev->constraints->state_mem);
615 	case PM_SUSPEND_MAX:
616 		return suspend_set_state(rdev,
617 			&rdev->constraints->state_disk);
618 	default:
619 		return -EINVAL;
620 	}
621 }
622 
623 static void print_constraints(struct regulator_dev *rdev)
624 {
625 	struct regulation_constraints *constraints = rdev->constraints;
626 	char buf[80];
627 	int count;
628 
629 	if (rdev->desc->type == REGULATOR_VOLTAGE) {
630 		if (constraints->min_uV == constraints->max_uV)
631 			count = sprintf(buf, "%d mV ",
632 					constraints->min_uV / 1000);
633 		else
634 			count = sprintf(buf, "%d <--> %d mV ",
635 					constraints->min_uV / 1000,
636 					constraints->max_uV / 1000);
637 	} else {
638 		if (constraints->min_uA == constraints->max_uA)
639 			count = sprintf(buf, "%d mA ",
640 					constraints->min_uA / 1000);
641 		else
642 			count = sprintf(buf, "%d <--> %d mA ",
643 					constraints->min_uA / 1000,
644 					constraints->max_uA / 1000);
645 	}
646 	if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
647 		count += sprintf(buf + count, "fast ");
648 	if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
649 		count += sprintf(buf + count, "normal ");
650 	if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
651 		count += sprintf(buf + count, "idle ");
652 	if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
653 		count += sprintf(buf + count, "standby");
654 
655 	printk(KERN_INFO "regulator: %s: %s\n", rdev->desc->name, buf);
656 }
657 
658 /**
659  * set_machine_constraints - sets regulator constraints
660  * @regulator: regulator source
661  *
662  * Allows platform initialisation code to define and constrain
663  * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
664  * Constraints *must* be set by platform code in order for some
665  * regulator operations to proceed i.e. set_voltage, set_current_limit,
666  * set_mode.
667  */
668 static int set_machine_constraints(struct regulator_dev *rdev,
669 	struct regulation_constraints *constraints)
670 {
671 	int ret = 0;
672 
673 	rdev->constraints = constraints;
674 
675 	/* do we need to apply the constraint voltage */
676 	if (rdev->constraints->apply_uV &&
677 		rdev->constraints->min_uV == rdev->constraints->max_uV &&
678 		rdev->desc->ops->set_voltage) {
679 		ret = rdev->desc->ops->set_voltage(rdev,
680 			rdev->constraints->min_uV, rdev->constraints->max_uV);
681 			if (ret < 0) {
682 				printk(KERN_ERR "%s: failed to apply %duV"
683 					" constraint\n", __func__,
684 					rdev->constraints->min_uV);
685 				rdev->constraints = NULL;
686 				goto out;
687 			}
688 	}
689 
690 	/* are we enabled at boot time by firmware / bootloader */
691 	if (rdev->constraints->boot_on)
692 		rdev->use_count = 1;
693 
694 	/* do we need to setup our suspend state */
695 	if (constraints->initial_state)
696 		ret = suspend_prepare(rdev, constraints->initial_state);
697 
698 	print_constraints(rdev);
699 out:
700 	return ret;
701 }
702 
703 /**
704  * set_supply - set regulator supply regulator
705  * @regulator: regulator name
706  * @supply: supply regulator name
707  *
708  * Called by platform initialisation code to set the supply regulator for this
709  * regulator. This ensures that a regulators supply will also be enabled by the
710  * core if it's child is enabled.
711  */
712 static int set_supply(struct regulator_dev *rdev,
713 	struct regulator_dev *supply_rdev)
714 {
715 	int err;
716 
717 	err = sysfs_create_link(&rdev->dev.kobj, &supply_rdev->dev.kobj,
718 				"supply");
719 	if (err) {
720 		printk(KERN_ERR
721 		       "%s: could not add device link %s err %d\n",
722 		       __func__, supply_rdev->dev.kobj.name, err);
723 		       goto out;
724 	}
725 	rdev->supply = supply_rdev;
726 	list_add(&rdev->slist, &supply_rdev->supply_list);
727 out:
728 	return err;
729 }
730 
731 /**
732  * set_consumer_device_supply: Bind a regulator to a symbolic supply
733  * @regulator: regulator source
734  * @dev:       device the supply applies to
735  * @supply:    symbolic name for supply
736  *
737  * Allows platform initialisation code to map physical regulator
738  * sources to symbolic names for supplies for use by devices.  Devices
739  * should use these symbolic names to request regulators, avoiding the
740  * need to provide board-specific regulator names as platform data.
741  */
742 static int set_consumer_device_supply(struct regulator_dev *rdev,
743 	struct device *consumer_dev, const char *supply)
744 {
745 	struct regulator_map *node;
746 
747 	if (supply == NULL)
748 		return -EINVAL;
749 
750 	node = kmalloc(sizeof(struct regulator_map), GFP_KERNEL);
751 	if (node == NULL)
752 		return -ENOMEM;
753 
754 	node->regulator = rdev;
755 	node->dev = consumer_dev;
756 	node->supply = supply;
757 
758 	list_add(&node->list, &regulator_map_list);
759 	return 0;
760 }
761 
762 static void unset_consumer_device_supply(struct regulator_dev *rdev,
763 	struct device *consumer_dev)
764 {
765 	struct regulator_map *node, *n;
766 
767 	list_for_each_entry_safe(node, n, &regulator_map_list, list) {
768 		if (rdev == node->regulator &&
769 			consumer_dev == node->dev) {
770 			list_del(&node->list);
771 			kfree(node);
772 			return;
773 		}
774 	}
775 }
776 
777 #define REG_STR_SIZE	32
778 
779 static struct regulator *create_regulator(struct regulator_dev *rdev,
780 					  struct device *dev,
781 					  const char *supply_name)
782 {
783 	struct regulator *regulator;
784 	char buf[REG_STR_SIZE];
785 	int err, size;
786 
787 	regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
788 	if (regulator == NULL)
789 		return NULL;
790 
791 	mutex_lock(&rdev->mutex);
792 	regulator->rdev = rdev;
793 	list_add(&regulator->list, &rdev->consumer_list);
794 
795 	if (dev) {
796 		/* create a 'requested_microamps_name' sysfs entry */
797 		size = scnprintf(buf, REG_STR_SIZE, "microamps_requested_%s",
798 			supply_name);
799 		if (size >= REG_STR_SIZE)
800 			goto overflow_err;
801 
802 		regulator->dev = dev;
803 		regulator->dev_attr.attr.name = kstrdup(buf, GFP_KERNEL);
804 		if (regulator->dev_attr.attr.name == NULL)
805 			goto attr_name_err;
806 
807 		regulator->dev_attr.attr.owner = THIS_MODULE;
808 		regulator->dev_attr.attr.mode = 0444;
809 		regulator->dev_attr.show = device_requested_uA_show;
810 		err = device_create_file(dev, &regulator->dev_attr);
811 		if (err < 0) {
812 			printk(KERN_WARNING "%s: could not add regulator_dev"
813 				" load sysfs\n", __func__);
814 			goto attr_name_err;
815 		}
816 
817 		/* also add a link to the device sysfs entry */
818 		size = scnprintf(buf, REG_STR_SIZE, "%s-%s",
819 				 dev->kobj.name, supply_name);
820 		if (size >= REG_STR_SIZE)
821 			goto attr_err;
822 
823 		regulator->supply_name = kstrdup(buf, GFP_KERNEL);
824 		if (regulator->supply_name == NULL)
825 			goto attr_err;
826 
827 		err = sysfs_create_link(&rdev->dev.kobj, &dev->kobj,
828 					buf);
829 		if (err) {
830 			printk(KERN_WARNING
831 			       "%s: could not add device link %s err %d\n",
832 			       __func__, dev->kobj.name, err);
833 			device_remove_file(dev, &regulator->dev_attr);
834 			goto link_name_err;
835 		}
836 	}
837 	mutex_unlock(&rdev->mutex);
838 	return regulator;
839 link_name_err:
840 	kfree(regulator->supply_name);
841 attr_err:
842 	device_remove_file(regulator->dev, &regulator->dev_attr);
843 attr_name_err:
844 	kfree(regulator->dev_attr.attr.name);
845 overflow_err:
846 	list_del(&regulator->list);
847 	kfree(regulator);
848 	mutex_unlock(&rdev->mutex);
849 	return NULL;
850 }
851 
852 /**
853  * regulator_get - lookup and obtain a reference to a regulator.
854  * @dev: device for regulator "consumer"
855  * @id: Supply name or regulator ID.
856  *
857  * Returns a struct regulator corresponding to the regulator producer,
858  * or IS_ERR() condition containing errno.  Use of supply names
859  * configured via regulator_set_device_supply() is strongly
860  * encouraged.
861  */
862 struct regulator *regulator_get(struct device *dev, const char *id)
863 {
864 	struct regulator_dev *rdev;
865 	struct regulator_map *map;
866 	struct regulator *regulator = ERR_PTR(-ENODEV);
867 
868 	if (id == NULL) {
869 		printk(KERN_ERR "regulator: get() with no identifier\n");
870 		return regulator;
871 	}
872 
873 	mutex_lock(&regulator_list_mutex);
874 
875 	list_for_each_entry(map, &regulator_map_list, list) {
876 		if (dev == map->dev &&
877 		    strcmp(map->supply, id) == 0) {
878 			rdev = map->regulator;
879 			goto found;
880 		}
881 	}
882 	printk(KERN_ERR "regulator: Unable to get requested regulator: %s\n",
883 	       id);
884 	mutex_unlock(&regulator_list_mutex);
885 	return regulator;
886 
887 found:
888 	if (!try_module_get(rdev->owner))
889 		goto out;
890 
891 	regulator = create_regulator(rdev, dev, id);
892 	if (regulator == NULL) {
893 		regulator = ERR_PTR(-ENOMEM);
894 		module_put(rdev->owner);
895 	}
896 
897 out:
898 	mutex_unlock(&regulator_list_mutex);
899 	return regulator;
900 }
901 EXPORT_SYMBOL_GPL(regulator_get);
902 
903 /**
904  * regulator_put - "free" the regulator source
905  * @regulator: regulator source
906  *
907  * Note: drivers must ensure that all regulator_enable calls made on this
908  * regulator source are balanced by regulator_disable calls prior to calling
909  * this function.
910  */
911 void regulator_put(struct regulator *regulator)
912 {
913 	struct regulator_dev *rdev;
914 
915 	if (regulator == NULL || IS_ERR(regulator))
916 		return;
917 
918 	if (regulator->enabled) {
919 		printk(KERN_WARNING "Releasing supply %s while enabled\n",
920 		       regulator->supply_name);
921 		WARN_ON(regulator->enabled);
922 		regulator_disable(regulator);
923 	}
924 
925 	mutex_lock(&regulator_list_mutex);
926 	rdev = regulator->rdev;
927 
928 	/* remove any sysfs entries */
929 	if (regulator->dev) {
930 		sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
931 		kfree(regulator->supply_name);
932 		device_remove_file(regulator->dev, &regulator->dev_attr);
933 		kfree(regulator->dev_attr.attr.name);
934 	}
935 	list_del(&regulator->list);
936 	kfree(regulator);
937 
938 	module_put(rdev->owner);
939 	mutex_unlock(&regulator_list_mutex);
940 }
941 EXPORT_SYMBOL_GPL(regulator_put);
942 
943 /* locks held by regulator_enable() */
944 static int _regulator_enable(struct regulator_dev *rdev)
945 {
946 	int ret = -EINVAL;
947 
948 	if (!rdev->constraints) {
949 		printk(KERN_ERR "%s: %s has no constraints\n",
950 		       __func__, rdev->desc->name);
951 		return ret;
952 	}
953 
954 	/* do we need to enable the supply regulator first */
955 	if (rdev->supply) {
956 		ret = _regulator_enable(rdev->supply);
957 		if (ret < 0) {
958 			printk(KERN_ERR "%s: failed to enable %s: %d\n",
959 			       __func__, rdev->desc->name, ret);
960 			return ret;
961 		}
962 	}
963 
964 	/* check voltage and requested load before enabling */
965 	if (rdev->desc->ops->enable) {
966 
967 		if (rdev->constraints &&
968 			(rdev->constraints->valid_ops_mask &
969 			REGULATOR_CHANGE_DRMS))
970 			drms_uA_update(rdev);
971 
972 		ret = rdev->desc->ops->enable(rdev);
973 		if (ret < 0) {
974 			printk(KERN_ERR "%s: failed to enable %s: %d\n",
975 			       __func__, rdev->desc->name, ret);
976 			return ret;
977 		}
978 		rdev->use_count++;
979 		return ret;
980 	}
981 
982 	return ret;
983 }
984 
985 /**
986  * regulator_enable - enable regulator output
987  * @regulator: regulator source
988  *
989  * Enable the regulator output at the predefined voltage or current value.
990  * NOTE: the output value can be set by other drivers, boot loader or may be
991  * hardwired in the regulator.
992  * NOTE: calls to regulator_enable() must be balanced with calls to
993  * regulator_disable().
994  */
995 int regulator_enable(struct regulator *regulator)
996 {
997 	int ret;
998 
999 	if (regulator->enabled) {
1000 		printk(KERN_CRIT "Regulator %s already enabled\n",
1001 		       regulator->supply_name);
1002 		WARN_ON(regulator->enabled);
1003 		return 0;
1004 	}
1005 
1006 	mutex_lock(&regulator->rdev->mutex);
1007 	regulator->enabled = 1;
1008 	ret = _regulator_enable(regulator->rdev);
1009 	if (ret != 0)
1010 		regulator->enabled = 0;
1011 	mutex_unlock(&regulator->rdev->mutex);
1012 	return ret;
1013 }
1014 EXPORT_SYMBOL_GPL(regulator_enable);
1015 
1016 /* locks held by regulator_disable() */
1017 static int _regulator_disable(struct regulator_dev *rdev)
1018 {
1019 	int ret = 0;
1020 
1021 	/* are we the last user and permitted to disable ? */
1022 	if (rdev->use_count == 1 && !rdev->constraints->always_on) {
1023 
1024 		/* we are last user */
1025 		if (rdev->desc->ops->disable) {
1026 			ret = rdev->desc->ops->disable(rdev);
1027 			if (ret < 0) {
1028 				printk(KERN_ERR "%s: failed to disable %s\n",
1029 				       __func__, rdev->desc->name);
1030 				return ret;
1031 			}
1032 		}
1033 
1034 		/* decrease our supplies ref count and disable if required */
1035 		if (rdev->supply)
1036 			_regulator_disable(rdev->supply);
1037 
1038 		rdev->use_count = 0;
1039 	} else if (rdev->use_count > 1) {
1040 
1041 		if (rdev->constraints &&
1042 			(rdev->constraints->valid_ops_mask &
1043 			REGULATOR_CHANGE_DRMS))
1044 			drms_uA_update(rdev);
1045 
1046 		rdev->use_count--;
1047 	}
1048 	return ret;
1049 }
1050 
1051 /**
1052  * regulator_disable - disable regulator output
1053  * @regulator: regulator source
1054  *
1055  * Disable the regulator output voltage or current.
1056  * NOTE: this will only disable the regulator output if no other consumer
1057  * devices have it enabled.
1058  * NOTE: calls to regulator_enable() must be balanced with calls to
1059  * regulator_disable().
1060  */
1061 int regulator_disable(struct regulator *regulator)
1062 {
1063 	int ret;
1064 
1065 	if (!regulator->enabled) {
1066 		printk(KERN_ERR "%s: not in use by this consumer\n",
1067 			__func__);
1068 		return 0;
1069 	}
1070 
1071 	mutex_lock(&regulator->rdev->mutex);
1072 	regulator->enabled = 0;
1073 	regulator->uA_load = 0;
1074 	ret = _regulator_disable(regulator->rdev);
1075 	mutex_unlock(&regulator->rdev->mutex);
1076 	return ret;
1077 }
1078 EXPORT_SYMBOL_GPL(regulator_disable);
1079 
1080 /* locks held by regulator_force_disable() */
1081 static int _regulator_force_disable(struct regulator_dev *rdev)
1082 {
1083 	int ret = 0;
1084 
1085 	/* force disable */
1086 	if (rdev->desc->ops->disable) {
1087 		/* ah well, who wants to live forever... */
1088 		ret = rdev->desc->ops->disable(rdev);
1089 		if (ret < 0) {
1090 			printk(KERN_ERR "%s: failed to force disable %s\n",
1091 			       __func__, rdev->desc->name);
1092 			return ret;
1093 		}
1094 		/* notify other consumers that power has been forced off */
1095 		_notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE,
1096 			NULL);
1097 	}
1098 
1099 	/* decrease our supplies ref count and disable if required */
1100 	if (rdev->supply)
1101 		_regulator_disable(rdev->supply);
1102 
1103 	rdev->use_count = 0;
1104 	return ret;
1105 }
1106 
1107 /**
1108  * regulator_force_disable - force disable regulator output
1109  * @regulator: regulator source
1110  *
1111  * Forcibly disable the regulator output voltage or current.
1112  * NOTE: this *will* disable the regulator output even if other consumer
1113  * devices have it enabled. This should be used for situations when device
1114  * damage will likely occur if the regulator is not disabled (e.g. over temp).
1115  */
1116 int regulator_force_disable(struct regulator *regulator)
1117 {
1118 	int ret;
1119 
1120 	mutex_lock(&regulator->rdev->mutex);
1121 	regulator->enabled = 0;
1122 	regulator->uA_load = 0;
1123 	ret = _regulator_force_disable(regulator->rdev);
1124 	mutex_unlock(&regulator->rdev->mutex);
1125 	return ret;
1126 }
1127 EXPORT_SYMBOL_GPL(regulator_force_disable);
1128 
1129 static int _regulator_is_enabled(struct regulator_dev *rdev)
1130 {
1131 	int ret;
1132 
1133 	mutex_lock(&rdev->mutex);
1134 
1135 	/* sanity check */
1136 	if (!rdev->desc->ops->is_enabled) {
1137 		ret = -EINVAL;
1138 		goto out;
1139 	}
1140 
1141 	ret = rdev->desc->ops->is_enabled(rdev);
1142 out:
1143 	mutex_unlock(&rdev->mutex);
1144 	return ret;
1145 }
1146 
1147 /**
1148  * regulator_is_enabled - is the regulator output enabled
1149  * @regulator: regulator source
1150  *
1151  * Returns zero for disabled otherwise return number of enable requests.
1152  */
1153 int regulator_is_enabled(struct regulator *regulator)
1154 {
1155 	return _regulator_is_enabled(regulator->rdev);
1156 }
1157 EXPORT_SYMBOL_GPL(regulator_is_enabled);
1158 
1159 /**
1160  * regulator_set_voltage - set regulator output voltage
1161  * @regulator: regulator source
1162  * @min_uV: Minimum required voltage in uV
1163  * @max_uV: Maximum acceptable voltage in uV
1164  *
1165  * Sets a voltage regulator to the desired output voltage. This can be set
1166  * during any regulator state. IOW, regulator can be disabled or enabled.
1167  *
1168  * If the regulator is enabled then the voltage will change to the new value
1169  * immediately otherwise if the regulator is disabled the regulator will
1170  * output at the new voltage when enabled.
1171  *
1172  * NOTE: If the regulator is shared between several devices then the lowest
1173  * request voltage that meets the system constraints will be used.
1174  * NOTE: Regulator system constraints must be set for this regulator before
1175  * calling this function otherwise this call will fail.
1176  */
1177 int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
1178 {
1179 	struct regulator_dev *rdev = regulator->rdev;
1180 	int ret;
1181 
1182 	mutex_lock(&rdev->mutex);
1183 
1184 	/* sanity check */
1185 	if (!rdev->desc->ops->set_voltage) {
1186 		ret = -EINVAL;
1187 		goto out;
1188 	}
1189 
1190 	/* constraints check */
1191 	ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
1192 	if (ret < 0)
1193 		goto out;
1194 	regulator->min_uV = min_uV;
1195 	regulator->max_uV = max_uV;
1196 	ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV);
1197 
1198 out:
1199 	mutex_unlock(&rdev->mutex);
1200 	return ret;
1201 }
1202 EXPORT_SYMBOL_GPL(regulator_set_voltage);
1203 
1204 static int _regulator_get_voltage(struct regulator_dev *rdev)
1205 {
1206 	/* sanity check */
1207 	if (rdev->desc->ops->get_voltage)
1208 		return rdev->desc->ops->get_voltage(rdev);
1209 	else
1210 		return -EINVAL;
1211 }
1212 
1213 /**
1214  * regulator_get_voltage - get regulator output voltage
1215  * @regulator: regulator source
1216  *
1217  * This returns the current regulator voltage in uV.
1218  *
1219  * NOTE: If the regulator is disabled it will return the voltage value. This
1220  * function should not be used to determine regulator state.
1221  */
1222 int regulator_get_voltage(struct regulator *regulator)
1223 {
1224 	int ret;
1225 
1226 	mutex_lock(&regulator->rdev->mutex);
1227 
1228 	ret = _regulator_get_voltage(regulator->rdev);
1229 
1230 	mutex_unlock(&regulator->rdev->mutex);
1231 
1232 	return ret;
1233 }
1234 EXPORT_SYMBOL_GPL(regulator_get_voltage);
1235 
1236 /**
1237  * regulator_set_current_limit - set regulator output current limit
1238  * @regulator: regulator source
1239  * @min_uA: Minimuum supported current in uA
1240  * @max_uA: Maximum supported current in uA
1241  *
1242  * Sets current sink to the desired output current. This can be set during
1243  * any regulator state. IOW, regulator can be disabled or enabled.
1244  *
1245  * If the regulator is enabled then the current will change to the new value
1246  * immediately otherwise if the regulator is disabled the regulator will
1247  * output at the new current when enabled.
1248  *
1249  * NOTE: Regulator system constraints must be set for this regulator before
1250  * calling this function otherwise this call will fail.
1251  */
1252 int regulator_set_current_limit(struct regulator *regulator,
1253 			       int min_uA, int max_uA)
1254 {
1255 	struct regulator_dev *rdev = regulator->rdev;
1256 	int ret;
1257 
1258 	mutex_lock(&rdev->mutex);
1259 
1260 	/* sanity check */
1261 	if (!rdev->desc->ops->set_current_limit) {
1262 		ret = -EINVAL;
1263 		goto out;
1264 	}
1265 
1266 	/* constraints check */
1267 	ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
1268 	if (ret < 0)
1269 		goto out;
1270 
1271 	ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
1272 out:
1273 	mutex_unlock(&rdev->mutex);
1274 	return ret;
1275 }
1276 EXPORT_SYMBOL_GPL(regulator_set_current_limit);
1277 
1278 static int _regulator_get_current_limit(struct regulator_dev *rdev)
1279 {
1280 	int ret;
1281 
1282 	mutex_lock(&rdev->mutex);
1283 
1284 	/* sanity check */
1285 	if (!rdev->desc->ops->get_current_limit) {
1286 		ret = -EINVAL;
1287 		goto out;
1288 	}
1289 
1290 	ret = rdev->desc->ops->get_current_limit(rdev);
1291 out:
1292 	mutex_unlock(&rdev->mutex);
1293 	return ret;
1294 }
1295 
1296 /**
1297  * regulator_get_current_limit - get regulator output current
1298  * @regulator: regulator source
1299  *
1300  * This returns the current supplied by the specified current sink in uA.
1301  *
1302  * NOTE: If the regulator is disabled it will return the current value. This
1303  * function should not be used to determine regulator state.
1304  */
1305 int regulator_get_current_limit(struct regulator *regulator)
1306 {
1307 	return _regulator_get_current_limit(regulator->rdev);
1308 }
1309 EXPORT_SYMBOL_GPL(regulator_get_current_limit);
1310 
1311 /**
1312  * regulator_set_mode - set regulator operating mode
1313  * @regulator: regulator source
1314  * @mode: operating mode - one of the REGULATOR_MODE constants
1315  *
1316  * Set regulator operating mode to increase regulator efficiency or improve
1317  * regulation performance.
1318  *
1319  * NOTE: Regulator system constraints must be set for this regulator before
1320  * calling this function otherwise this call will fail.
1321  */
1322 int regulator_set_mode(struct regulator *regulator, unsigned int mode)
1323 {
1324 	struct regulator_dev *rdev = regulator->rdev;
1325 	int ret;
1326 
1327 	mutex_lock(&rdev->mutex);
1328 
1329 	/* sanity check */
1330 	if (!rdev->desc->ops->set_mode) {
1331 		ret = -EINVAL;
1332 		goto out;
1333 	}
1334 
1335 	/* constraints check */
1336 	ret = regulator_check_mode(rdev, mode);
1337 	if (ret < 0)
1338 		goto out;
1339 
1340 	ret = rdev->desc->ops->set_mode(rdev, mode);
1341 out:
1342 	mutex_unlock(&rdev->mutex);
1343 	return ret;
1344 }
1345 EXPORT_SYMBOL_GPL(regulator_set_mode);
1346 
1347 static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
1348 {
1349 	int ret;
1350 
1351 	mutex_lock(&rdev->mutex);
1352 
1353 	/* sanity check */
1354 	if (!rdev->desc->ops->get_mode) {
1355 		ret = -EINVAL;
1356 		goto out;
1357 	}
1358 
1359 	ret = rdev->desc->ops->get_mode(rdev);
1360 out:
1361 	mutex_unlock(&rdev->mutex);
1362 	return ret;
1363 }
1364 
1365 /**
1366  * regulator_get_mode - get regulator operating mode
1367  * @regulator: regulator source
1368  *
1369  * Get the current regulator operating mode.
1370  */
1371 unsigned int regulator_get_mode(struct regulator *regulator)
1372 {
1373 	return _regulator_get_mode(regulator->rdev);
1374 }
1375 EXPORT_SYMBOL_GPL(regulator_get_mode);
1376 
1377 /**
1378  * regulator_set_optimum_mode - set regulator optimum operating mode
1379  * @regulator: regulator source
1380  * @uA_load: load current
1381  *
1382  * Notifies the regulator core of a new device load. This is then used by
1383  * DRMS (if enabled by constraints) to set the most efficient regulator
1384  * operating mode for the new regulator loading.
1385  *
1386  * Consumer devices notify their supply regulator of the maximum power
1387  * they will require (can be taken from device datasheet in the power
1388  * consumption tables) when they change operational status and hence power
1389  * state. Examples of operational state changes that can affect power
1390  * consumption are :-
1391  *
1392  *    o Device is opened / closed.
1393  *    o Device I/O is about to begin or has just finished.
1394  *    o Device is idling in between work.
1395  *
1396  * This information is also exported via sysfs to userspace.
1397  *
1398  * DRMS will sum the total requested load on the regulator and change
1399  * to the most efficient operating mode if platform constraints allow.
1400  *
1401  * Returns the new regulator mode or error.
1402  */
1403 int regulator_set_optimum_mode(struct regulator *regulator, int uA_load)
1404 {
1405 	struct regulator_dev *rdev = regulator->rdev;
1406 	struct regulator *consumer;
1407 	int ret, output_uV, input_uV, total_uA_load = 0;
1408 	unsigned int mode;
1409 
1410 	mutex_lock(&rdev->mutex);
1411 
1412 	regulator->uA_load = uA_load;
1413 	ret = regulator_check_drms(rdev);
1414 	if (ret < 0)
1415 		goto out;
1416 	ret = -EINVAL;
1417 
1418 	/* sanity check */
1419 	if (!rdev->desc->ops->get_optimum_mode)
1420 		goto out;
1421 
1422 	/* get output voltage */
1423 	output_uV = rdev->desc->ops->get_voltage(rdev);
1424 	if (output_uV <= 0) {
1425 		printk(KERN_ERR "%s: invalid output voltage found for %s\n",
1426 			__func__, rdev->desc->name);
1427 		goto out;
1428 	}
1429 
1430 	/* get input voltage */
1431 	if (rdev->supply && rdev->supply->desc->ops->get_voltage)
1432 		input_uV = rdev->supply->desc->ops->get_voltage(rdev->supply);
1433 	else
1434 		input_uV = rdev->constraints->input_uV;
1435 	if (input_uV <= 0) {
1436 		printk(KERN_ERR "%s: invalid input voltage found for %s\n",
1437 			__func__, rdev->desc->name);
1438 		goto out;
1439 	}
1440 
1441 	/* calc total requested load for this regulator */
1442 	list_for_each_entry(consumer, &rdev->consumer_list, list)
1443 	    total_uA_load += consumer->uA_load;
1444 
1445 	mode = rdev->desc->ops->get_optimum_mode(rdev,
1446 						 input_uV, output_uV,
1447 						 total_uA_load);
1448 	if (ret <= 0) {
1449 		printk(KERN_ERR "%s: failed to get optimum mode for %s @"
1450 			" %d uA %d -> %d uV\n", __func__, rdev->desc->name,
1451 			total_uA_load, input_uV, output_uV);
1452 		goto out;
1453 	}
1454 
1455 	ret = rdev->desc->ops->set_mode(rdev, mode);
1456 	if (ret <= 0) {
1457 		printk(KERN_ERR "%s: failed to set optimum mode %x for %s\n",
1458 			__func__, mode, rdev->desc->name);
1459 		goto out;
1460 	}
1461 	ret = mode;
1462 out:
1463 	mutex_unlock(&rdev->mutex);
1464 	return ret;
1465 }
1466 EXPORT_SYMBOL_GPL(regulator_set_optimum_mode);
1467 
1468 /**
1469  * regulator_register_notifier - register regulator event notifier
1470  * @regulator: regulator source
1471  * @notifier_block: notifier block
1472  *
1473  * Register notifier block to receive regulator events.
1474  */
1475 int regulator_register_notifier(struct regulator *regulator,
1476 			      struct notifier_block *nb)
1477 {
1478 	return blocking_notifier_chain_register(&regulator->rdev->notifier,
1479 						nb);
1480 }
1481 EXPORT_SYMBOL_GPL(regulator_register_notifier);
1482 
1483 /**
1484  * regulator_unregister_notifier - unregister regulator event notifier
1485  * @regulator: regulator source
1486  * @notifier_block: notifier block
1487  *
1488  * Unregister regulator event notifier block.
1489  */
1490 int regulator_unregister_notifier(struct regulator *regulator,
1491 				struct notifier_block *nb)
1492 {
1493 	return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
1494 						  nb);
1495 }
1496 EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
1497 
1498 /* notify regulator consumers and downstream regulator consumers */
1499 static void _notifier_call_chain(struct regulator_dev *rdev,
1500 				  unsigned long event, void *data)
1501 {
1502 	struct regulator_dev *_rdev;
1503 
1504 	/* call rdev chain first */
1505 	mutex_lock(&rdev->mutex);
1506 	blocking_notifier_call_chain(&rdev->notifier, event, NULL);
1507 	mutex_unlock(&rdev->mutex);
1508 
1509 	/* now notify regulator we supply */
1510 	list_for_each_entry(_rdev, &rdev->supply_list, slist)
1511 		_notifier_call_chain(_rdev, event, data);
1512 }
1513 
1514 /**
1515  * regulator_bulk_get - get multiple regulator consumers
1516  *
1517  * @dev:           Device to supply
1518  * @num_consumers: Number of consumers to register
1519  * @consumers:     Configuration of consumers; clients are stored here.
1520  *
1521  * @return 0 on success, an errno on failure.
1522  *
1523  * This helper function allows drivers to get several regulator
1524  * consumers in one operation.  If any of the regulators cannot be
1525  * acquired then any regulators that were allocated will be freed
1526  * before returning to the caller.
1527  */
1528 int regulator_bulk_get(struct device *dev, int num_consumers,
1529 		       struct regulator_bulk_data *consumers)
1530 {
1531 	int i;
1532 	int ret;
1533 
1534 	for (i = 0; i < num_consumers; i++)
1535 		consumers[i].consumer = NULL;
1536 
1537 	for (i = 0; i < num_consumers; i++) {
1538 		consumers[i].consumer = regulator_get(dev,
1539 						      consumers[i].supply);
1540 		if (IS_ERR(consumers[i].consumer)) {
1541 			dev_err(dev, "Failed to get supply '%s'\n",
1542 				consumers[i].supply);
1543 			ret = PTR_ERR(consumers[i].consumer);
1544 			consumers[i].consumer = NULL;
1545 			goto err;
1546 		}
1547 	}
1548 
1549 	return 0;
1550 
1551 err:
1552 	for (i = 0; i < num_consumers && consumers[i].consumer; i++)
1553 		regulator_put(consumers[i].consumer);
1554 
1555 	return ret;
1556 }
1557 EXPORT_SYMBOL_GPL(regulator_bulk_get);
1558 
1559 /**
1560  * regulator_bulk_enable - enable multiple regulator consumers
1561  *
1562  * @num_consumers: Number of consumers
1563  * @consumers:     Consumer data; clients are stored here.
1564  * @return         0 on success, an errno on failure
1565  *
1566  * This convenience API allows consumers to enable multiple regulator
1567  * clients in a single API call.  If any consumers cannot be enabled
1568  * then any others that were enabled will be disabled again prior to
1569  * return.
1570  */
1571 int regulator_bulk_enable(int num_consumers,
1572 			  struct regulator_bulk_data *consumers)
1573 {
1574 	int i;
1575 	int ret;
1576 
1577 	for (i = 0; i < num_consumers; i++) {
1578 		ret = regulator_enable(consumers[i].consumer);
1579 		if (ret != 0)
1580 			goto err;
1581 	}
1582 
1583 	return 0;
1584 
1585 err:
1586 	printk(KERN_ERR "Failed to enable %s\n", consumers[i].supply);
1587 	for (i = 0; i < num_consumers; i++)
1588 		regulator_disable(consumers[i].consumer);
1589 
1590 	return ret;
1591 }
1592 EXPORT_SYMBOL_GPL(regulator_bulk_enable);
1593 
1594 /**
1595  * regulator_bulk_disable - disable multiple regulator consumers
1596  *
1597  * @num_consumers: Number of consumers
1598  * @consumers:     Consumer data; clients are stored here.
1599  * @return         0 on success, an errno on failure
1600  *
1601  * This convenience API allows consumers to disable multiple regulator
1602  * clients in a single API call.  If any consumers cannot be enabled
1603  * then any others that were disabled will be disabled again prior to
1604  * return.
1605  */
1606 int regulator_bulk_disable(int num_consumers,
1607 			   struct regulator_bulk_data *consumers)
1608 {
1609 	int i;
1610 	int ret;
1611 
1612 	for (i = 0; i < num_consumers; i++) {
1613 		ret = regulator_disable(consumers[i].consumer);
1614 		if (ret != 0)
1615 			goto err;
1616 	}
1617 
1618 	return 0;
1619 
1620 err:
1621 	printk(KERN_ERR "Failed to disable %s\n", consumers[i].supply);
1622 	for (i = 0; i < num_consumers; i++)
1623 		regulator_enable(consumers[i].consumer);
1624 
1625 	return ret;
1626 }
1627 EXPORT_SYMBOL_GPL(regulator_bulk_disable);
1628 
1629 /**
1630  * regulator_bulk_free - free multiple regulator consumers
1631  *
1632  * @num_consumers: Number of consumers
1633  * @consumers:     Consumer data; clients are stored here.
1634  *
1635  * This convenience API allows consumers to free multiple regulator
1636  * clients in a single API call.
1637  */
1638 void regulator_bulk_free(int num_consumers,
1639 			 struct regulator_bulk_data *consumers)
1640 {
1641 	int i;
1642 
1643 	for (i = 0; i < num_consumers; i++) {
1644 		regulator_put(consumers[i].consumer);
1645 		consumers[i].consumer = NULL;
1646 	}
1647 }
1648 EXPORT_SYMBOL_GPL(regulator_bulk_free);
1649 
1650 /**
1651  * regulator_notifier_call_chain - call regulator event notifier
1652  * @regulator: regulator source
1653  * @event: notifier block
1654  * @data:
1655  *
1656  * Called by regulator drivers to notify clients a regulator event has
1657  * occurred. We also notify regulator clients downstream.
1658  */
1659 int regulator_notifier_call_chain(struct regulator_dev *rdev,
1660 				  unsigned long event, void *data)
1661 {
1662 	_notifier_call_chain(rdev, event, data);
1663 	return NOTIFY_DONE;
1664 
1665 }
1666 EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
1667 
1668 /**
1669  * regulator_register - register regulator
1670  * @regulator: regulator source
1671  * @reg_data: private regulator data
1672  *
1673  * Called by regulator drivers to register a regulator.
1674  * Returns 0 on success.
1675  */
1676 struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc,
1677 	struct device *dev, void *driver_data)
1678 {
1679 	static atomic_t regulator_no = ATOMIC_INIT(0);
1680 	struct regulator_dev *rdev;
1681 	struct regulator_init_data *init_data = dev->platform_data;
1682 	int ret, i;
1683 
1684 	if (regulator_desc == NULL)
1685 		return ERR_PTR(-EINVAL);
1686 
1687 	if (regulator_desc->name == NULL || regulator_desc->ops == NULL)
1688 		return ERR_PTR(-EINVAL);
1689 
1690 	if (!regulator_desc->type == REGULATOR_VOLTAGE &&
1691 	    !regulator_desc->type == REGULATOR_CURRENT)
1692 		return ERR_PTR(-EINVAL);
1693 
1694 	rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
1695 	if (rdev == NULL)
1696 		return ERR_PTR(-ENOMEM);
1697 
1698 	mutex_lock(&regulator_list_mutex);
1699 
1700 	mutex_init(&rdev->mutex);
1701 	rdev->reg_data = driver_data;
1702 	rdev->owner = regulator_desc->owner;
1703 	rdev->desc = regulator_desc;
1704 	INIT_LIST_HEAD(&rdev->consumer_list);
1705 	INIT_LIST_HEAD(&rdev->supply_list);
1706 	INIT_LIST_HEAD(&rdev->list);
1707 	INIT_LIST_HEAD(&rdev->slist);
1708 	BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
1709 
1710 	/* preform any regulator specific init */
1711 	if (init_data->regulator_init) {
1712 		ret = init_data->regulator_init(rdev->reg_data);
1713 		if (ret < 0) {
1714 			kfree(rdev);
1715 			rdev = ERR_PTR(ret);
1716 			goto out;
1717 		}
1718 	}
1719 
1720 	/* set regulator constraints */
1721 	ret = set_machine_constraints(rdev, &init_data->constraints);
1722 	if (ret < 0) {
1723 		kfree(rdev);
1724 		rdev = ERR_PTR(ret);
1725 		goto out;
1726 	}
1727 
1728 	/* register with sysfs */
1729 	rdev->dev.class = &regulator_class;
1730 	rdev->dev.parent = dev;
1731 	snprintf(rdev->dev.bus_id, sizeof(rdev->dev.bus_id),
1732 		 "regulator.%d", atomic_inc_return(&regulator_no) - 1);
1733 	ret = device_register(&rdev->dev);
1734 	if (ret != 0) {
1735 		kfree(rdev);
1736 		rdev = ERR_PTR(ret);
1737 		goto out;
1738 	}
1739 
1740 	dev_set_drvdata(&rdev->dev, rdev);
1741 
1742 	/* set supply regulator if it exists */
1743 	if (init_data->supply_regulator_dev) {
1744 		ret = set_supply(rdev,
1745 			dev_get_drvdata(init_data->supply_regulator_dev));
1746 		if (ret < 0) {
1747 			device_unregister(&rdev->dev);
1748 			kfree(rdev);
1749 			rdev = ERR_PTR(ret);
1750 			goto out;
1751 		}
1752 	}
1753 
1754 	/* add consumers devices */
1755 	for (i = 0; i < init_data->num_consumer_supplies; i++) {
1756 		ret = set_consumer_device_supply(rdev,
1757 			init_data->consumer_supplies[i].dev,
1758 			init_data->consumer_supplies[i].supply);
1759 		if (ret < 0) {
1760 			for (--i; i >= 0; i--)
1761 				unset_consumer_device_supply(rdev,
1762 					init_data->consumer_supplies[i].dev);
1763 			device_unregister(&rdev->dev);
1764 			kfree(rdev);
1765 			rdev = ERR_PTR(ret);
1766 			goto out;
1767 		}
1768 	}
1769 
1770 	list_add(&rdev->list, &regulator_list);
1771 out:
1772 	mutex_unlock(&regulator_list_mutex);
1773 	return rdev;
1774 }
1775 EXPORT_SYMBOL_GPL(regulator_register);
1776 
1777 /**
1778  * regulator_unregister - unregister regulator
1779  * @regulator: regulator source
1780  *
1781  * Called by regulator drivers to unregister a regulator.
1782  */
1783 void regulator_unregister(struct regulator_dev *rdev)
1784 {
1785 	if (rdev == NULL)
1786 		return;
1787 
1788 	mutex_lock(&regulator_list_mutex);
1789 	list_del(&rdev->list);
1790 	if (rdev->supply)
1791 		sysfs_remove_link(&rdev->dev.kobj, "supply");
1792 	device_unregister(&rdev->dev);
1793 	mutex_unlock(&regulator_list_mutex);
1794 }
1795 EXPORT_SYMBOL_GPL(regulator_unregister);
1796 
1797 /**
1798  * regulator_suspend_prepare: prepare regulators for system wide suspend
1799  * @state: system suspend state
1800  *
1801  * Configure each regulator with it's suspend operating parameters for state.
1802  * This will usually be called by machine suspend code prior to supending.
1803  */
1804 int regulator_suspend_prepare(suspend_state_t state)
1805 {
1806 	struct regulator_dev *rdev;
1807 	int ret = 0;
1808 
1809 	/* ON is handled by regulator active state */
1810 	if (state == PM_SUSPEND_ON)
1811 		return -EINVAL;
1812 
1813 	mutex_lock(&regulator_list_mutex);
1814 	list_for_each_entry(rdev, &regulator_list, list) {
1815 
1816 		mutex_lock(&rdev->mutex);
1817 		ret = suspend_prepare(rdev, state);
1818 		mutex_unlock(&rdev->mutex);
1819 
1820 		if (ret < 0) {
1821 			printk(KERN_ERR "%s: failed to prepare %s\n",
1822 				__func__, rdev->desc->name);
1823 			goto out;
1824 		}
1825 	}
1826 out:
1827 	mutex_unlock(&regulator_list_mutex);
1828 	return ret;
1829 }
1830 EXPORT_SYMBOL_GPL(regulator_suspend_prepare);
1831 
1832 /**
1833  * rdev_get_drvdata - get rdev regulator driver data
1834  * @regulator: regulator
1835  *
1836  * Get rdev regulator driver private data. This call can be used in the
1837  * regulator driver context.
1838  */
1839 void *rdev_get_drvdata(struct regulator_dev *rdev)
1840 {
1841 	return rdev->reg_data;
1842 }
1843 EXPORT_SYMBOL_GPL(rdev_get_drvdata);
1844 
1845 /**
1846  * regulator_get_drvdata - get regulator driver data
1847  * @regulator: regulator
1848  *
1849  * Get regulator driver private data. This call can be used in the consumer
1850  * driver context when non API regulator specific functions need to be called.
1851  */
1852 void *regulator_get_drvdata(struct regulator *regulator)
1853 {
1854 	return regulator->rdev->reg_data;
1855 }
1856 EXPORT_SYMBOL_GPL(regulator_get_drvdata);
1857 
1858 /**
1859  * regulator_set_drvdata - set regulator driver data
1860  * @regulator: regulator
1861  * @data: data
1862  */
1863 void regulator_set_drvdata(struct regulator *regulator, void *data)
1864 {
1865 	regulator->rdev->reg_data = data;
1866 }
1867 EXPORT_SYMBOL_GPL(regulator_set_drvdata);
1868 
1869 /**
1870  * regulator_get_id - get regulator ID
1871  * @regulator: regulator
1872  */
1873 int rdev_get_id(struct regulator_dev *rdev)
1874 {
1875 	return rdev->desc->id;
1876 }
1877 EXPORT_SYMBOL_GPL(rdev_get_id);
1878 
1879 struct device *rdev_get_dev(struct regulator_dev *rdev)
1880 {
1881 	return &rdev->dev;
1882 }
1883 EXPORT_SYMBOL_GPL(rdev_get_dev);
1884 
1885 void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
1886 {
1887 	return reg_init_data->driver_data;
1888 }
1889 EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
1890 
1891 static int __init regulator_init(void)
1892 {
1893 	printk(KERN_INFO "regulator: core version %s\n", REGULATOR_VERSION);
1894 	return class_register(&regulator_class);
1895 }
1896 
1897 /* init early to allow our consumers to complete system booting */
1898 core_initcall(regulator_init);
1899