xref: /linux/drivers/regulator/core.c (revision d39d0ed196aa1685bb24771e92f78633c66ac9cb)
1 /*
2  * core.c  --  Voltage/Current Regulator framework.
3  *
4  * Copyright 2007, 2008 Wolfson Microelectronics PLC.
5  * Copyright 2008 SlimLogic Ltd.
6  *
7  * Author: Liam Girdwood <lrg@slimlogic.co.uk>
8  *
9  *  This program is free software; you can redistribute  it and/or modify it
10  *  under  the terms of  the GNU General  Public License as published by the
11  *  Free Software Foundation;  either version 2 of the  License, or (at your
12  *  option) any later version.
13  *
14  */
15 
16 #include <linux/kernel.h>
17 #include <linux/init.h>
18 #include <linux/device.h>
19 #include <linux/slab.h>
20 #include <linux/err.h>
21 #include <linux/mutex.h>
22 #include <linux/suspend.h>
23 #include <linux/delay.h>
24 #include <linux/regulator/consumer.h>
25 #include <linux/regulator/driver.h>
26 #include <linux/regulator/machine.h>
27 
28 #include "dummy.h"
29 
30 #define REGULATOR_VERSION "0.5"
31 
32 static DEFINE_MUTEX(regulator_list_mutex);
33 static LIST_HEAD(regulator_list);
34 static LIST_HEAD(regulator_map_list);
35 static int has_full_constraints;
36 
37 /*
38  * struct regulator_map
39  *
40  * Used to provide symbolic supply names to devices.
41  */
42 struct regulator_map {
43 	struct list_head list;
44 	const char *dev_name;   /* The dev_name() for the consumer */
45 	const char *supply;
46 	struct regulator_dev *regulator;
47 };
48 
49 /*
50  * struct regulator
51  *
52  * One for each consumer device.
53  */
54 struct regulator {
55 	struct device *dev;
56 	struct list_head list;
57 	int uA_load;
58 	int min_uV;
59 	int max_uV;
60 	char *supply_name;
61 	struct device_attribute dev_attr;
62 	struct regulator_dev *rdev;
63 };
64 
65 static int _regulator_is_enabled(struct regulator_dev *rdev);
66 static int _regulator_disable(struct regulator_dev *rdev);
67 static int _regulator_get_voltage(struct regulator_dev *rdev);
68 static int _regulator_get_current_limit(struct regulator_dev *rdev);
69 static unsigned int _regulator_get_mode(struct regulator_dev *rdev);
70 static void _notifier_call_chain(struct regulator_dev *rdev,
71 				  unsigned long event, void *data);
72 
73 static const char *rdev_get_name(struct regulator_dev *rdev)
74 {
75 	if (rdev->constraints && rdev->constraints->name)
76 		return rdev->constraints->name;
77 	else if (rdev->desc->name)
78 		return rdev->desc->name;
79 	else
80 		return "";
81 }
82 
83 /* gets the regulator for a given consumer device */
84 static struct regulator *get_device_regulator(struct device *dev)
85 {
86 	struct regulator *regulator = NULL;
87 	struct regulator_dev *rdev;
88 
89 	mutex_lock(&regulator_list_mutex);
90 	list_for_each_entry(rdev, &regulator_list, list) {
91 		mutex_lock(&rdev->mutex);
92 		list_for_each_entry(regulator, &rdev->consumer_list, list) {
93 			if (regulator->dev == dev) {
94 				mutex_unlock(&rdev->mutex);
95 				mutex_unlock(&regulator_list_mutex);
96 				return regulator;
97 			}
98 		}
99 		mutex_unlock(&rdev->mutex);
100 	}
101 	mutex_unlock(&regulator_list_mutex);
102 	return NULL;
103 }
104 
105 /* Platform voltage constraint check */
106 static int regulator_check_voltage(struct regulator_dev *rdev,
107 				   int *min_uV, int *max_uV)
108 {
109 	BUG_ON(*min_uV > *max_uV);
110 
111 	if (!rdev->constraints) {
112 		printk(KERN_ERR "%s: no constraints for %s\n", __func__,
113 		       rdev_get_name(rdev));
114 		return -ENODEV;
115 	}
116 	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
117 		printk(KERN_ERR "%s: operation not allowed for %s\n",
118 		       __func__, rdev_get_name(rdev));
119 		return -EPERM;
120 	}
121 
122 	if (*max_uV > rdev->constraints->max_uV)
123 		*max_uV = rdev->constraints->max_uV;
124 	if (*min_uV < rdev->constraints->min_uV)
125 		*min_uV = rdev->constraints->min_uV;
126 
127 	if (*min_uV > *max_uV)
128 		return -EINVAL;
129 
130 	return 0;
131 }
132 
133 /* current constraint check */
134 static int regulator_check_current_limit(struct regulator_dev *rdev,
135 					int *min_uA, int *max_uA)
136 {
137 	BUG_ON(*min_uA > *max_uA);
138 
139 	if (!rdev->constraints) {
140 		printk(KERN_ERR "%s: no constraints for %s\n", __func__,
141 		       rdev_get_name(rdev));
142 		return -ENODEV;
143 	}
144 	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_CURRENT)) {
145 		printk(KERN_ERR "%s: operation not allowed for %s\n",
146 		       __func__, rdev_get_name(rdev));
147 		return -EPERM;
148 	}
149 
150 	if (*max_uA > rdev->constraints->max_uA)
151 		*max_uA = rdev->constraints->max_uA;
152 	if (*min_uA < rdev->constraints->min_uA)
153 		*min_uA = rdev->constraints->min_uA;
154 
155 	if (*min_uA > *max_uA)
156 		return -EINVAL;
157 
158 	return 0;
159 }
160 
161 /* operating mode constraint check */
162 static int regulator_check_mode(struct regulator_dev *rdev, int mode)
163 {
164 	switch (mode) {
165 	case REGULATOR_MODE_FAST:
166 	case REGULATOR_MODE_NORMAL:
167 	case REGULATOR_MODE_IDLE:
168 	case REGULATOR_MODE_STANDBY:
169 		break;
170 	default:
171 		return -EINVAL;
172 	}
173 
174 	if (!rdev->constraints) {
175 		printk(KERN_ERR "%s: no constraints for %s\n", __func__,
176 		       rdev_get_name(rdev));
177 		return -ENODEV;
178 	}
179 	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_MODE)) {
180 		printk(KERN_ERR "%s: operation not allowed for %s\n",
181 		       __func__, rdev_get_name(rdev));
182 		return -EPERM;
183 	}
184 	if (!(rdev->constraints->valid_modes_mask & mode)) {
185 		printk(KERN_ERR "%s: invalid mode %x for %s\n",
186 		       __func__, mode, rdev_get_name(rdev));
187 		return -EINVAL;
188 	}
189 	return 0;
190 }
191 
192 /* dynamic regulator mode switching constraint check */
193 static int regulator_check_drms(struct regulator_dev *rdev)
194 {
195 	if (!rdev->constraints) {
196 		printk(KERN_ERR "%s: no constraints for %s\n", __func__,
197 		       rdev_get_name(rdev));
198 		return -ENODEV;
199 	}
200 	if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS)) {
201 		printk(KERN_ERR "%s: operation not allowed for %s\n",
202 		       __func__, rdev_get_name(rdev));
203 		return -EPERM;
204 	}
205 	return 0;
206 }
207 
208 static ssize_t device_requested_uA_show(struct device *dev,
209 			     struct device_attribute *attr, char *buf)
210 {
211 	struct regulator *regulator;
212 
213 	regulator = get_device_regulator(dev);
214 	if (regulator == NULL)
215 		return 0;
216 
217 	return sprintf(buf, "%d\n", regulator->uA_load);
218 }
219 
220 static ssize_t regulator_uV_show(struct device *dev,
221 				struct device_attribute *attr, char *buf)
222 {
223 	struct regulator_dev *rdev = dev_get_drvdata(dev);
224 	ssize_t ret;
225 
226 	mutex_lock(&rdev->mutex);
227 	ret = sprintf(buf, "%d\n", _regulator_get_voltage(rdev));
228 	mutex_unlock(&rdev->mutex);
229 
230 	return ret;
231 }
232 static DEVICE_ATTR(microvolts, 0444, regulator_uV_show, NULL);
233 
234 static ssize_t regulator_uA_show(struct device *dev,
235 				struct device_attribute *attr, char *buf)
236 {
237 	struct regulator_dev *rdev = dev_get_drvdata(dev);
238 
239 	return sprintf(buf, "%d\n", _regulator_get_current_limit(rdev));
240 }
241 static DEVICE_ATTR(microamps, 0444, regulator_uA_show, NULL);
242 
243 static ssize_t regulator_name_show(struct device *dev,
244 			     struct device_attribute *attr, char *buf)
245 {
246 	struct regulator_dev *rdev = dev_get_drvdata(dev);
247 
248 	return sprintf(buf, "%s\n", rdev_get_name(rdev));
249 }
250 
251 static ssize_t regulator_print_opmode(char *buf, int mode)
252 {
253 	switch (mode) {
254 	case REGULATOR_MODE_FAST:
255 		return sprintf(buf, "fast\n");
256 	case REGULATOR_MODE_NORMAL:
257 		return sprintf(buf, "normal\n");
258 	case REGULATOR_MODE_IDLE:
259 		return sprintf(buf, "idle\n");
260 	case REGULATOR_MODE_STANDBY:
261 		return sprintf(buf, "standby\n");
262 	}
263 	return sprintf(buf, "unknown\n");
264 }
265 
266 static ssize_t regulator_opmode_show(struct device *dev,
267 				    struct device_attribute *attr, char *buf)
268 {
269 	struct regulator_dev *rdev = dev_get_drvdata(dev);
270 
271 	return regulator_print_opmode(buf, _regulator_get_mode(rdev));
272 }
273 static DEVICE_ATTR(opmode, 0444, regulator_opmode_show, NULL);
274 
275 static ssize_t regulator_print_state(char *buf, int state)
276 {
277 	if (state > 0)
278 		return sprintf(buf, "enabled\n");
279 	else if (state == 0)
280 		return sprintf(buf, "disabled\n");
281 	else
282 		return sprintf(buf, "unknown\n");
283 }
284 
285 static ssize_t regulator_state_show(struct device *dev,
286 				   struct device_attribute *attr, char *buf)
287 {
288 	struct regulator_dev *rdev = dev_get_drvdata(dev);
289 	ssize_t ret;
290 
291 	mutex_lock(&rdev->mutex);
292 	ret = regulator_print_state(buf, _regulator_is_enabled(rdev));
293 	mutex_unlock(&rdev->mutex);
294 
295 	return ret;
296 }
297 static DEVICE_ATTR(state, 0444, regulator_state_show, NULL);
298 
299 static ssize_t regulator_status_show(struct device *dev,
300 				   struct device_attribute *attr, char *buf)
301 {
302 	struct regulator_dev *rdev = dev_get_drvdata(dev);
303 	int status;
304 	char *label;
305 
306 	status = rdev->desc->ops->get_status(rdev);
307 	if (status < 0)
308 		return status;
309 
310 	switch (status) {
311 	case REGULATOR_STATUS_OFF:
312 		label = "off";
313 		break;
314 	case REGULATOR_STATUS_ON:
315 		label = "on";
316 		break;
317 	case REGULATOR_STATUS_ERROR:
318 		label = "error";
319 		break;
320 	case REGULATOR_STATUS_FAST:
321 		label = "fast";
322 		break;
323 	case REGULATOR_STATUS_NORMAL:
324 		label = "normal";
325 		break;
326 	case REGULATOR_STATUS_IDLE:
327 		label = "idle";
328 		break;
329 	case REGULATOR_STATUS_STANDBY:
330 		label = "standby";
331 		break;
332 	default:
333 		return -ERANGE;
334 	}
335 
336 	return sprintf(buf, "%s\n", label);
337 }
338 static DEVICE_ATTR(status, 0444, regulator_status_show, NULL);
339 
340 static ssize_t regulator_min_uA_show(struct device *dev,
341 				    struct device_attribute *attr, char *buf)
342 {
343 	struct regulator_dev *rdev = dev_get_drvdata(dev);
344 
345 	if (!rdev->constraints)
346 		return sprintf(buf, "constraint not defined\n");
347 
348 	return sprintf(buf, "%d\n", rdev->constraints->min_uA);
349 }
350 static DEVICE_ATTR(min_microamps, 0444, regulator_min_uA_show, NULL);
351 
352 static ssize_t regulator_max_uA_show(struct device *dev,
353 				    struct device_attribute *attr, char *buf)
354 {
355 	struct regulator_dev *rdev = dev_get_drvdata(dev);
356 
357 	if (!rdev->constraints)
358 		return sprintf(buf, "constraint not defined\n");
359 
360 	return sprintf(buf, "%d\n", rdev->constraints->max_uA);
361 }
362 static DEVICE_ATTR(max_microamps, 0444, regulator_max_uA_show, NULL);
363 
364 static ssize_t regulator_min_uV_show(struct device *dev,
365 				    struct device_attribute *attr, char *buf)
366 {
367 	struct regulator_dev *rdev = dev_get_drvdata(dev);
368 
369 	if (!rdev->constraints)
370 		return sprintf(buf, "constraint not defined\n");
371 
372 	return sprintf(buf, "%d\n", rdev->constraints->min_uV);
373 }
374 static DEVICE_ATTR(min_microvolts, 0444, regulator_min_uV_show, NULL);
375 
376 static ssize_t regulator_max_uV_show(struct device *dev,
377 				    struct device_attribute *attr, char *buf)
378 {
379 	struct regulator_dev *rdev = dev_get_drvdata(dev);
380 
381 	if (!rdev->constraints)
382 		return sprintf(buf, "constraint not defined\n");
383 
384 	return sprintf(buf, "%d\n", rdev->constraints->max_uV);
385 }
386 static DEVICE_ATTR(max_microvolts, 0444, regulator_max_uV_show, NULL);
387 
388 static ssize_t regulator_total_uA_show(struct device *dev,
389 				      struct device_attribute *attr, char *buf)
390 {
391 	struct regulator_dev *rdev = dev_get_drvdata(dev);
392 	struct regulator *regulator;
393 	int uA = 0;
394 
395 	mutex_lock(&rdev->mutex);
396 	list_for_each_entry(regulator, &rdev->consumer_list, list)
397 		uA += regulator->uA_load;
398 	mutex_unlock(&rdev->mutex);
399 	return sprintf(buf, "%d\n", uA);
400 }
401 static DEVICE_ATTR(requested_microamps, 0444, regulator_total_uA_show, NULL);
402 
403 static ssize_t regulator_num_users_show(struct device *dev,
404 				      struct device_attribute *attr, char *buf)
405 {
406 	struct regulator_dev *rdev = dev_get_drvdata(dev);
407 	return sprintf(buf, "%d\n", rdev->use_count);
408 }
409 
410 static ssize_t regulator_type_show(struct device *dev,
411 				  struct device_attribute *attr, char *buf)
412 {
413 	struct regulator_dev *rdev = dev_get_drvdata(dev);
414 
415 	switch (rdev->desc->type) {
416 	case REGULATOR_VOLTAGE:
417 		return sprintf(buf, "voltage\n");
418 	case REGULATOR_CURRENT:
419 		return sprintf(buf, "current\n");
420 	}
421 	return sprintf(buf, "unknown\n");
422 }
423 
424 static ssize_t regulator_suspend_mem_uV_show(struct device *dev,
425 				struct device_attribute *attr, char *buf)
426 {
427 	struct regulator_dev *rdev = dev_get_drvdata(dev);
428 
429 	return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
430 }
431 static DEVICE_ATTR(suspend_mem_microvolts, 0444,
432 		regulator_suspend_mem_uV_show, NULL);
433 
434 static ssize_t regulator_suspend_disk_uV_show(struct device *dev,
435 				struct device_attribute *attr, char *buf)
436 {
437 	struct regulator_dev *rdev = dev_get_drvdata(dev);
438 
439 	return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
440 }
441 static DEVICE_ATTR(suspend_disk_microvolts, 0444,
442 		regulator_suspend_disk_uV_show, NULL);
443 
444 static ssize_t regulator_suspend_standby_uV_show(struct device *dev,
445 				struct device_attribute *attr, char *buf)
446 {
447 	struct regulator_dev *rdev = dev_get_drvdata(dev);
448 
449 	return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
450 }
451 static DEVICE_ATTR(suspend_standby_microvolts, 0444,
452 		regulator_suspend_standby_uV_show, NULL);
453 
454 static ssize_t regulator_suspend_mem_mode_show(struct device *dev,
455 				struct device_attribute *attr, char *buf)
456 {
457 	struct regulator_dev *rdev = dev_get_drvdata(dev);
458 
459 	return regulator_print_opmode(buf,
460 		rdev->constraints->state_mem.mode);
461 }
462 static DEVICE_ATTR(suspend_mem_mode, 0444,
463 		regulator_suspend_mem_mode_show, NULL);
464 
465 static ssize_t regulator_suspend_disk_mode_show(struct device *dev,
466 				struct device_attribute *attr, char *buf)
467 {
468 	struct regulator_dev *rdev = dev_get_drvdata(dev);
469 
470 	return regulator_print_opmode(buf,
471 		rdev->constraints->state_disk.mode);
472 }
473 static DEVICE_ATTR(suspend_disk_mode, 0444,
474 		regulator_suspend_disk_mode_show, NULL);
475 
476 static ssize_t regulator_suspend_standby_mode_show(struct device *dev,
477 				struct device_attribute *attr, char *buf)
478 {
479 	struct regulator_dev *rdev = dev_get_drvdata(dev);
480 
481 	return regulator_print_opmode(buf,
482 		rdev->constraints->state_standby.mode);
483 }
484 static DEVICE_ATTR(suspend_standby_mode, 0444,
485 		regulator_suspend_standby_mode_show, NULL);
486 
487 static ssize_t regulator_suspend_mem_state_show(struct device *dev,
488 				   struct device_attribute *attr, char *buf)
489 {
490 	struct regulator_dev *rdev = dev_get_drvdata(dev);
491 
492 	return regulator_print_state(buf,
493 			rdev->constraints->state_mem.enabled);
494 }
495 static DEVICE_ATTR(suspend_mem_state, 0444,
496 		regulator_suspend_mem_state_show, NULL);
497 
498 static ssize_t regulator_suspend_disk_state_show(struct device *dev,
499 				   struct device_attribute *attr, char *buf)
500 {
501 	struct regulator_dev *rdev = dev_get_drvdata(dev);
502 
503 	return regulator_print_state(buf,
504 			rdev->constraints->state_disk.enabled);
505 }
506 static DEVICE_ATTR(suspend_disk_state, 0444,
507 		regulator_suspend_disk_state_show, NULL);
508 
509 static ssize_t regulator_suspend_standby_state_show(struct device *dev,
510 				   struct device_attribute *attr, char *buf)
511 {
512 	struct regulator_dev *rdev = dev_get_drvdata(dev);
513 
514 	return regulator_print_state(buf,
515 			rdev->constraints->state_standby.enabled);
516 }
517 static DEVICE_ATTR(suspend_standby_state, 0444,
518 		regulator_suspend_standby_state_show, NULL);
519 
520 
521 /*
522  * These are the only attributes are present for all regulators.
523  * Other attributes are a function of regulator functionality.
524  */
525 static struct device_attribute regulator_dev_attrs[] = {
526 	__ATTR(name, 0444, regulator_name_show, NULL),
527 	__ATTR(num_users, 0444, regulator_num_users_show, NULL),
528 	__ATTR(type, 0444, regulator_type_show, NULL),
529 	__ATTR_NULL,
530 };
531 
532 static void regulator_dev_release(struct device *dev)
533 {
534 	struct regulator_dev *rdev = dev_get_drvdata(dev);
535 	kfree(rdev);
536 }
537 
538 static struct class regulator_class = {
539 	.name = "regulator",
540 	.dev_release = regulator_dev_release,
541 	.dev_attrs = regulator_dev_attrs,
542 };
543 
544 /* Calculate the new optimum regulator operating mode based on the new total
545  * consumer load. All locks held by caller */
546 static void drms_uA_update(struct regulator_dev *rdev)
547 {
548 	struct regulator *sibling;
549 	int current_uA = 0, output_uV, input_uV, err;
550 	unsigned int mode;
551 
552 	err = regulator_check_drms(rdev);
553 	if (err < 0 || !rdev->desc->ops->get_optimum_mode ||
554 	    !rdev->desc->ops->get_voltage || !rdev->desc->ops->set_mode)
555 		return;
556 
557 	/* get output voltage */
558 	output_uV = rdev->desc->ops->get_voltage(rdev);
559 	if (output_uV <= 0)
560 		return;
561 
562 	/* get input voltage */
563 	if (rdev->supply && rdev->supply->desc->ops->get_voltage)
564 		input_uV = rdev->supply->desc->ops->get_voltage(rdev->supply);
565 	else
566 		input_uV = rdev->constraints->input_uV;
567 	if (input_uV <= 0)
568 		return;
569 
570 	/* calc total requested load */
571 	list_for_each_entry(sibling, &rdev->consumer_list, list)
572 		current_uA += sibling->uA_load;
573 
574 	/* now get the optimum mode for our new total regulator load */
575 	mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
576 						  output_uV, current_uA);
577 
578 	/* check the new mode is allowed */
579 	err = regulator_check_mode(rdev, mode);
580 	if (err == 0)
581 		rdev->desc->ops->set_mode(rdev, mode);
582 }
583 
584 static int suspend_set_state(struct regulator_dev *rdev,
585 	struct regulator_state *rstate)
586 {
587 	int ret = 0;
588 	bool can_set_state;
589 
590 	can_set_state = rdev->desc->ops->set_suspend_enable &&
591 		rdev->desc->ops->set_suspend_disable;
592 
593 	/* If we have no suspend mode configration don't set anything;
594 	 * only warn if the driver actually makes the suspend mode
595 	 * configurable.
596 	 */
597 	if (!rstate->enabled && !rstate->disabled) {
598 		if (can_set_state)
599 			printk(KERN_WARNING "%s: No configuration for %s\n",
600 			       __func__, rdev_get_name(rdev));
601 		return 0;
602 	}
603 
604 	if (rstate->enabled && rstate->disabled) {
605 		printk(KERN_ERR "%s: invalid configuration for %s\n",
606 		       __func__, rdev_get_name(rdev));
607 		return -EINVAL;
608 	}
609 
610 	if (!can_set_state) {
611 		printk(KERN_ERR "%s: no way to set suspend state\n",
612 			__func__);
613 		return -EINVAL;
614 	}
615 
616 	if (rstate->enabled)
617 		ret = rdev->desc->ops->set_suspend_enable(rdev);
618 	else
619 		ret = rdev->desc->ops->set_suspend_disable(rdev);
620 	if (ret < 0) {
621 		printk(KERN_ERR "%s: failed to enabled/disable\n", __func__);
622 		return ret;
623 	}
624 
625 	if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
626 		ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
627 		if (ret < 0) {
628 			printk(KERN_ERR "%s: failed to set voltage\n",
629 				__func__);
630 			return ret;
631 		}
632 	}
633 
634 	if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
635 		ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
636 		if (ret < 0) {
637 			printk(KERN_ERR "%s: failed to set mode\n", __func__);
638 			return ret;
639 		}
640 	}
641 	return ret;
642 }
643 
644 /* locks held by caller */
645 static int suspend_prepare(struct regulator_dev *rdev, suspend_state_t state)
646 {
647 	if (!rdev->constraints)
648 		return -EINVAL;
649 
650 	switch (state) {
651 	case PM_SUSPEND_STANDBY:
652 		return suspend_set_state(rdev,
653 			&rdev->constraints->state_standby);
654 	case PM_SUSPEND_MEM:
655 		return suspend_set_state(rdev,
656 			&rdev->constraints->state_mem);
657 	case PM_SUSPEND_MAX:
658 		return suspend_set_state(rdev,
659 			&rdev->constraints->state_disk);
660 	default:
661 		return -EINVAL;
662 	}
663 }
664 
665 static void print_constraints(struct regulator_dev *rdev)
666 {
667 	struct regulation_constraints *constraints = rdev->constraints;
668 	char buf[80] = "";
669 	int count = 0;
670 	int ret;
671 
672 	if (constraints->min_uV && constraints->max_uV) {
673 		if (constraints->min_uV == constraints->max_uV)
674 			count += sprintf(buf + count, "%d mV ",
675 					 constraints->min_uV / 1000);
676 		else
677 			count += sprintf(buf + count, "%d <--> %d mV ",
678 					 constraints->min_uV / 1000,
679 					 constraints->max_uV / 1000);
680 	}
681 
682 	if (!constraints->min_uV ||
683 	    constraints->min_uV != constraints->max_uV) {
684 		ret = _regulator_get_voltage(rdev);
685 		if (ret > 0)
686 			count += sprintf(buf + count, "at %d mV ", ret / 1000);
687 	}
688 
689 	if (constraints->min_uA && constraints->max_uA) {
690 		if (constraints->min_uA == constraints->max_uA)
691 			count += sprintf(buf + count, "%d mA ",
692 					 constraints->min_uA / 1000);
693 		else
694 			count += sprintf(buf + count, "%d <--> %d mA ",
695 					 constraints->min_uA / 1000,
696 					 constraints->max_uA / 1000);
697 	}
698 
699 	if (!constraints->min_uA ||
700 	    constraints->min_uA != constraints->max_uA) {
701 		ret = _regulator_get_current_limit(rdev);
702 		if (ret > 0)
703 			count += sprintf(buf + count, "at %d uA ", ret / 1000);
704 	}
705 
706 	if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
707 		count += sprintf(buf + count, "fast ");
708 	if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
709 		count += sprintf(buf + count, "normal ");
710 	if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
711 		count += sprintf(buf + count, "idle ");
712 	if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
713 		count += sprintf(buf + count, "standby");
714 
715 	printk(KERN_INFO "regulator: %s: %s\n", rdev_get_name(rdev), buf);
716 }
717 
718 static int machine_constraints_voltage(struct regulator_dev *rdev,
719 	struct regulation_constraints *constraints)
720 {
721 	struct regulator_ops *ops = rdev->desc->ops;
722 	const char *name = rdev_get_name(rdev);
723 	int ret;
724 
725 	/* do we need to apply the constraint voltage */
726 	if (rdev->constraints->apply_uV &&
727 		rdev->constraints->min_uV == rdev->constraints->max_uV &&
728 		ops->set_voltage) {
729 		ret = ops->set_voltage(rdev,
730 			rdev->constraints->min_uV, rdev->constraints->max_uV);
731 			if (ret < 0) {
732 				printk(KERN_ERR "%s: failed to apply %duV constraint to %s\n",
733 				       __func__,
734 				       rdev->constraints->min_uV, name);
735 				rdev->constraints = NULL;
736 				return ret;
737 			}
738 	}
739 
740 	/* constrain machine-level voltage specs to fit
741 	 * the actual range supported by this regulator.
742 	 */
743 	if (ops->list_voltage && rdev->desc->n_voltages) {
744 		int	count = rdev->desc->n_voltages;
745 		int	i;
746 		int	min_uV = INT_MAX;
747 		int	max_uV = INT_MIN;
748 		int	cmin = constraints->min_uV;
749 		int	cmax = constraints->max_uV;
750 
751 		/* it's safe to autoconfigure fixed-voltage supplies
752 		   and the constraints are used by list_voltage. */
753 		if (count == 1 && !cmin) {
754 			cmin = 1;
755 			cmax = INT_MAX;
756 			constraints->min_uV = cmin;
757 			constraints->max_uV = cmax;
758 		}
759 
760 		/* voltage constraints are optional */
761 		if ((cmin == 0) && (cmax == 0))
762 			return 0;
763 
764 		/* else require explicit machine-level constraints */
765 		if (cmin <= 0 || cmax <= 0 || cmax < cmin) {
766 			pr_err("%s: %s '%s' voltage constraints\n",
767 				       __func__, "invalid", name);
768 			return -EINVAL;
769 		}
770 
771 		/* initial: [cmin..cmax] valid, [min_uV..max_uV] not */
772 		for (i = 0; i < count; i++) {
773 			int	value;
774 
775 			value = ops->list_voltage(rdev, i);
776 			if (value <= 0)
777 				continue;
778 
779 			/* maybe adjust [min_uV..max_uV] */
780 			if (value >= cmin && value < min_uV)
781 				min_uV = value;
782 			if (value <= cmax && value > max_uV)
783 				max_uV = value;
784 		}
785 
786 		/* final: [min_uV..max_uV] valid iff constraints valid */
787 		if (max_uV < min_uV) {
788 			pr_err("%s: %s '%s' voltage constraints\n",
789 				       __func__, "unsupportable", name);
790 			return -EINVAL;
791 		}
792 
793 		/* use regulator's subset of machine constraints */
794 		if (constraints->min_uV < min_uV) {
795 			pr_debug("%s: override '%s' %s, %d -> %d\n",
796 				       __func__, name, "min_uV",
797 					constraints->min_uV, min_uV);
798 			constraints->min_uV = min_uV;
799 		}
800 		if (constraints->max_uV > max_uV) {
801 			pr_debug("%s: override '%s' %s, %d -> %d\n",
802 				       __func__, name, "max_uV",
803 					constraints->max_uV, max_uV);
804 			constraints->max_uV = max_uV;
805 		}
806 	}
807 
808 	return 0;
809 }
810 
811 /**
812  * set_machine_constraints - sets regulator constraints
813  * @rdev: regulator source
814  * @constraints: constraints to apply
815  *
816  * Allows platform initialisation code to define and constrain
817  * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
818  * Constraints *must* be set by platform code in order for some
819  * regulator operations to proceed i.e. set_voltage, set_current_limit,
820  * set_mode.
821  */
822 static int set_machine_constraints(struct regulator_dev *rdev,
823 	struct regulation_constraints *constraints)
824 {
825 	int ret = 0;
826 	const char *name;
827 	struct regulator_ops *ops = rdev->desc->ops;
828 
829 	rdev->constraints = constraints;
830 
831 	name = rdev_get_name(rdev);
832 
833 	ret = machine_constraints_voltage(rdev, constraints);
834 	if (ret != 0)
835 		goto out;
836 
837 	/* do we need to setup our suspend state */
838 	if (constraints->initial_state) {
839 		ret = suspend_prepare(rdev, constraints->initial_state);
840 		if (ret < 0) {
841 			printk(KERN_ERR "%s: failed to set suspend state for %s\n",
842 			       __func__, name);
843 			rdev->constraints = NULL;
844 			goto out;
845 		}
846 	}
847 
848 	if (constraints->initial_mode) {
849 		if (!ops->set_mode) {
850 			printk(KERN_ERR "%s: no set_mode operation for %s\n",
851 			       __func__, name);
852 			ret = -EINVAL;
853 			goto out;
854 		}
855 
856 		ret = ops->set_mode(rdev, constraints->initial_mode);
857 		if (ret < 0) {
858 			printk(KERN_ERR
859 			       "%s: failed to set initial mode for %s: %d\n",
860 			       __func__, name, ret);
861 			goto out;
862 		}
863 	}
864 
865 	/* If the constraints say the regulator should be on at this point
866 	 * and we have control then make sure it is enabled.
867 	 */
868 	if ((constraints->always_on || constraints->boot_on) && ops->enable) {
869 		ret = ops->enable(rdev);
870 		if (ret < 0) {
871 			printk(KERN_ERR "%s: failed to enable %s\n",
872 			       __func__, name);
873 			rdev->constraints = NULL;
874 			goto out;
875 		}
876 	}
877 
878 	print_constraints(rdev);
879 out:
880 	return ret;
881 }
882 
883 /**
884  * set_supply - set regulator supply regulator
885  * @rdev: regulator name
886  * @supply_rdev: supply regulator name
887  *
888  * Called by platform initialisation code to set the supply regulator for this
889  * regulator. This ensures that a regulators supply will also be enabled by the
890  * core if it's child is enabled.
891  */
892 static int set_supply(struct regulator_dev *rdev,
893 	struct regulator_dev *supply_rdev)
894 {
895 	int err;
896 
897 	err = sysfs_create_link(&rdev->dev.kobj, &supply_rdev->dev.kobj,
898 				"supply");
899 	if (err) {
900 		printk(KERN_ERR
901 		       "%s: could not add device link %s err %d\n",
902 		       __func__, supply_rdev->dev.kobj.name, err);
903 		       goto out;
904 	}
905 	rdev->supply = supply_rdev;
906 	list_add(&rdev->slist, &supply_rdev->supply_list);
907 out:
908 	return err;
909 }
910 
911 /**
912  * set_consumer_device_supply: Bind a regulator to a symbolic supply
913  * @rdev:         regulator source
914  * @consumer_dev: device the supply applies to
915  * @consumer_dev_name: dev_name() string for device supply applies to
916  * @supply:       symbolic name for supply
917  *
918  * Allows platform initialisation code to map physical regulator
919  * sources to symbolic names for supplies for use by devices.  Devices
920  * should use these symbolic names to request regulators, avoiding the
921  * need to provide board-specific regulator names as platform data.
922  *
923  * Only one of consumer_dev and consumer_dev_name may be specified.
924  */
925 static int set_consumer_device_supply(struct regulator_dev *rdev,
926 	struct device *consumer_dev, const char *consumer_dev_name,
927 	const char *supply)
928 {
929 	struct regulator_map *node;
930 	int has_dev;
931 
932 	if (consumer_dev && consumer_dev_name)
933 		return -EINVAL;
934 
935 	if (!consumer_dev_name && consumer_dev)
936 		consumer_dev_name = dev_name(consumer_dev);
937 
938 	if (supply == NULL)
939 		return -EINVAL;
940 
941 	if (consumer_dev_name != NULL)
942 		has_dev = 1;
943 	else
944 		has_dev = 0;
945 
946 	list_for_each_entry(node, &regulator_map_list, list) {
947 		if (node->dev_name && consumer_dev_name) {
948 			if (strcmp(node->dev_name, consumer_dev_name) != 0)
949 				continue;
950 		} else if (node->dev_name || consumer_dev_name) {
951 			continue;
952 		}
953 
954 		if (strcmp(node->supply, supply) != 0)
955 			continue;
956 
957 		dev_dbg(consumer_dev, "%s/%s is '%s' supply; fail %s/%s\n",
958 				dev_name(&node->regulator->dev),
959 				node->regulator->desc->name,
960 				supply,
961 				dev_name(&rdev->dev), rdev_get_name(rdev));
962 		return -EBUSY;
963 	}
964 
965 	node = kzalloc(sizeof(struct regulator_map), GFP_KERNEL);
966 	if (node == NULL)
967 		return -ENOMEM;
968 
969 	node->regulator = rdev;
970 	node->supply = supply;
971 
972 	if (has_dev) {
973 		node->dev_name = kstrdup(consumer_dev_name, GFP_KERNEL);
974 		if (node->dev_name == NULL) {
975 			kfree(node);
976 			return -ENOMEM;
977 		}
978 	}
979 
980 	list_add(&node->list, &regulator_map_list);
981 	return 0;
982 }
983 
984 static void unset_regulator_supplies(struct regulator_dev *rdev)
985 {
986 	struct regulator_map *node, *n;
987 
988 	list_for_each_entry_safe(node, n, &regulator_map_list, list) {
989 		if (rdev == node->regulator) {
990 			list_del(&node->list);
991 			kfree(node->dev_name);
992 			kfree(node);
993 		}
994 	}
995 }
996 
997 #define REG_STR_SIZE	32
998 
999 static struct regulator *create_regulator(struct regulator_dev *rdev,
1000 					  struct device *dev,
1001 					  const char *supply_name)
1002 {
1003 	struct regulator *regulator;
1004 	char buf[REG_STR_SIZE];
1005 	int err, size;
1006 
1007 	regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
1008 	if (regulator == NULL)
1009 		return NULL;
1010 
1011 	mutex_lock(&rdev->mutex);
1012 	regulator->rdev = rdev;
1013 	list_add(&regulator->list, &rdev->consumer_list);
1014 
1015 	if (dev) {
1016 		/* create a 'requested_microamps_name' sysfs entry */
1017 		size = scnprintf(buf, REG_STR_SIZE, "microamps_requested_%s",
1018 			supply_name);
1019 		if (size >= REG_STR_SIZE)
1020 			goto overflow_err;
1021 
1022 		regulator->dev = dev;
1023 		sysfs_attr_init(&regulator->dev_attr.attr);
1024 		regulator->dev_attr.attr.name = kstrdup(buf, GFP_KERNEL);
1025 		if (regulator->dev_attr.attr.name == NULL)
1026 			goto attr_name_err;
1027 
1028 		regulator->dev_attr.attr.mode = 0444;
1029 		regulator->dev_attr.show = device_requested_uA_show;
1030 		err = device_create_file(dev, &regulator->dev_attr);
1031 		if (err < 0) {
1032 			printk(KERN_WARNING "%s: could not add regulator_dev"
1033 				" load sysfs\n", __func__);
1034 			goto attr_name_err;
1035 		}
1036 
1037 		/* also add a link to the device sysfs entry */
1038 		size = scnprintf(buf, REG_STR_SIZE, "%s-%s",
1039 				 dev->kobj.name, supply_name);
1040 		if (size >= REG_STR_SIZE)
1041 			goto attr_err;
1042 
1043 		regulator->supply_name = kstrdup(buf, GFP_KERNEL);
1044 		if (regulator->supply_name == NULL)
1045 			goto attr_err;
1046 
1047 		err = sysfs_create_link(&rdev->dev.kobj, &dev->kobj,
1048 					buf);
1049 		if (err) {
1050 			printk(KERN_WARNING
1051 			       "%s: could not add device link %s err %d\n",
1052 			       __func__, dev->kobj.name, err);
1053 			device_remove_file(dev, &regulator->dev_attr);
1054 			goto link_name_err;
1055 		}
1056 	}
1057 	mutex_unlock(&rdev->mutex);
1058 	return regulator;
1059 link_name_err:
1060 	kfree(regulator->supply_name);
1061 attr_err:
1062 	device_remove_file(regulator->dev, &regulator->dev_attr);
1063 attr_name_err:
1064 	kfree(regulator->dev_attr.attr.name);
1065 overflow_err:
1066 	list_del(&regulator->list);
1067 	kfree(regulator);
1068 	mutex_unlock(&rdev->mutex);
1069 	return NULL;
1070 }
1071 
1072 static int _regulator_get_enable_time(struct regulator_dev *rdev)
1073 {
1074 	if (!rdev->desc->ops->enable_time)
1075 		return 0;
1076 	return rdev->desc->ops->enable_time(rdev);
1077 }
1078 
1079 /* Internal regulator request function */
1080 static struct regulator *_regulator_get(struct device *dev, const char *id,
1081 					int exclusive)
1082 {
1083 	struct regulator_dev *rdev;
1084 	struct regulator_map *map;
1085 	struct regulator *regulator = ERR_PTR(-ENODEV);
1086 	const char *devname = NULL;
1087 	int ret;
1088 
1089 	if (id == NULL) {
1090 		printk(KERN_ERR "regulator: get() with no identifier\n");
1091 		return regulator;
1092 	}
1093 
1094 	if (dev)
1095 		devname = dev_name(dev);
1096 
1097 	mutex_lock(&regulator_list_mutex);
1098 
1099 	list_for_each_entry(map, &regulator_map_list, list) {
1100 		/* If the mapping has a device set up it must match */
1101 		if (map->dev_name &&
1102 		    (!devname || strcmp(map->dev_name, devname)))
1103 			continue;
1104 
1105 		if (strcmp(map->supply, id) == 0) {
1106 			rdev = map->regulator;
1107 			goto found;
1108 		}
1109 	}
1110 
1111 #ifdef CONFIG_REGULATOR_DUMMY
1112 	if (!devname)
1113 		devname = "deviceless";
1114 
1115 	/* If the board didn't flag that it was fully constrained then
1116 	 * substitute in a dummy regulator so consumers can continue.
1117 	 */
1118 	if (!has_full_constraints) {
1119 		pr_warning("%s supply %s not found, using dummy regulator\n",
1120 			   devname, id);
1121 		rdev = dummy_regulator_rdev;
1122 		goto found;
1123 	}
1124 #endif
1125 
1126 	mutex_unlock(&regulator_list_mutex);
1127 	return regulator;
1128 
1129 found:
1130 	if (rdev->exclusive) {
1131 		regulator = ERR_PTR(-EPERM);
1132 		goto out;
1133 	}
1134 
1135 	if (exclusive && rdev->open_count) {
1136 		regulator = ERR_PTR(-EBUSY);
1137 		goto out;
1138 	}
1139 
1140 	if (!try_module_get(rdev->owner))
1141 		goto out;
1142 
1143 	regulator = create_regulator(rdev, dev, id);
1144 	if (regulator == NULL) {
1145 		regulator = ERR_PTR(-ENOMEM);
1146 		module_put(rdev->owner);
1147 	}
1148 
1149 	rdev->open_count++;
1150 	if (exclusive) {
1151 		rdev->exclusive = 1;
1152 
1153 		ret = _regulator_is_enabled(rdev);
1154 		if (ret > 0)
1155 			rdev->use_count = 1;
1156 		else
1157 			rdev->use_count = 0;
1158 	}
1159 
1160 out:
1161 	mutex_unlock(&regulator_list_mutex);
1162 
1163 	return regulator;
1164 }
1165 
1166 /**
1167  * regulator_get - lookup and obtain a reference to a regulator.
1168  * @dev: device for regulator "consumer"
1169  * @id: Supply name or regulator ID.
1170  *
1171  * Returns a struct regulator corresponding to the regulator producer,
1172  * or IS_ERR() condition containing errno.
1173  *
1174  * Use of supply names configured via regulator_set_device_supply() is
1175  * strongly encouraged.  It is recommended that the supply name used
1176  * should match the name used for the supply and/or the relevant
1177  * device pins in the datasheet.
1178  */
1179 struct regulator *regulator_get(struct device *dev, const char *id)
1180 {
1181 	return _regulator_get(dev, id, 0);
1182 }
1183 EXPORT_SYMBOL_GPL(regulator_get);
1184 
1185 /**
1186  * regulator_get_exclusive - obtain exclusive access to a regulator.
1187  * @dev: device for regulator "consumer"
1188  * @id: Supply name or regulator ID.
1189  *
1190  * Returns a struct regulator corresponding to the regulator producer,
1191  * or IS_ERR() condition containing errno.  Other consumers will be
1192  * unable to obtain this reference is held and the use count for the
1193  * regulator will be initialised to reflect the current state of the
1194  * regulator.
1195  *
1196  * This is intended for use by consumers which cannot tolerate shared
1197  * use of the regulator such as those which need to force the
1198  * regulator off for correct operation of the hardware they are
1199  * controlling.
1200  *
1201  * Use of supply names configured via regulator_set_device_supply() is
1202  * strongly encouraged.  It is recommended that the supply name used
1203  * should match the name used for the supply and/or the relevant
1204  * device pins in the datasheet.
1205  */
1206 struct regulator *regulator_get_exclusive(struct device *dev, const char *id)
1207 {
1208 	return _regulator_get(dev, id, 1);
1209 }
1210 EXPORT_SYMBOL_GPL(regulator_get_exclusive);
1211 
1212 /**
1213  * regulator_put - "free" the regulator source
1214  * @regulator: regulator source
1215  *
1216  * Note: drivers must ensure that all regulator_enable calls made on this
1217  * regulator source are balanced by regulator_disable calls prior to calling
1218  * this function.
1219  */
1220 void regulator_put(struct regulator *regulator)
1221 {
1222 	struct regulator_dev *rdev;
1223 
1224 	if (regulator == NULL || IS_ERR(regulator))
1225 		return;
1226 
1227 	mutex_lock(&regulator_list_mutex);
1228 	rdev = regulator->rdev;
1229 
1230 	/* remove any sysfs entries */
1231 	if (regulator->dev) {
1232 		sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
1233 		kfree(regulator->supply_name);
1234 		device_remove_file(regulator->dev, &regulator->dev_attr);
1235 		kfree(regulator->dev_attr.attr.name);
1236 	}
1237 	list_del(&regulator->list);
1238 	kfree(regulator);
1239 
1240 	rdev->open_count--;
1241 	rdev->exclusive = 0;
1242 
1243 	module_put(rdev->owner);
1244 	mutex_unlock(&regulator_list_mutex);
1245 }
1246 EXPORT_SYMBOL_GPL(regulator_put);
1247 
1248 static int _regulator_can_change_status(struct regulator_dev *rdev)
1249 {
1250 	if (!rdev->constraints)
1251 		return 0;
1252 
1253 	if (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_STATUS)
1254 		return 1;
1255 	else
1256 		return 0;
1257 }
1258 
1259 /* locks held by regulator_enable() */
1260 static int _regulator_enable(struct regulator_dev *rdev)
1261 {
1262 	int ret, delay;
1263 
1264 	/* do we need to enable the supply regulator first */
1265 	if (rdev->supply) {
1266 		ret = _regulator_enable(rdev->supply);
1267 		if (ret < 0) {
1268 			printk(KERN_ERR "%s: failed to enable %s: %d\n",
1269 			       __func__, rdev_get_name(rdev), ret);
1270 			return ret;
1271 		}
1272 	}
1273 
1274 	/* check voltage and requested load before enabling */
1275 	if (rdev->constraints &&
1276 	    (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS))
1277 		drms_uA_update(rdev);
1278 
1279 	if (rdev->use_count == 0) {
1280 		/* The regulator may on if it's not switchable or left on */
1281 		ret = _regulator_is_enabled(rdev);
1282 		if (ret == -EINVAL || ret == 0) {
1283 			if (!_regulator_can_change_status(rdev))
1284 				return -EPERM;
1285 
1286 			if (!rdev->desc->ops->enable)
1287 				return -EINVAL;
1288 
1289 			/* Query before enabling in case configuration
1290 			 * dependant.  */
1291 			ret = _regulator_get_enable_time(rdev);
1292 			if (ret >= 0) {
1293 				delay = ret;
1294 			} else {
1295 				printk(KERN_WARNING
1296 					"%s: enable_time() failed for %s: %d\n",
1297 					__func__, rdev_get_name(rdev),
1298 					ret);
1299 				delay = 0;
1300 			}
1301 
1302 			/* Allow the regulator to ramp; it would be useful
1303 			 * to extend this for bulk operations so that the
1304 			 * regulators can ramp together.  */
1305 			ret = rdev->desc->ops->enable(rdev);
1306 			if (ret < 0)
1307 				return ret;
1308 
1309 			if (delay >= 1000)
1310 				mdelay(delay / 1000);
1311 			else if (delay)
1312 				udelay(delay);
1313 
1314 		} else if (ret < 0) {
1315 			printk(KERN_ERR "%s: is_enabled() failed for %s: %d\n",
1316 			       __func__, rdev_get_name(rdev), ret);
1317 			return ret;
1318 		}
1319 		/* Fallthrough on positive return values - already enabled */
1320 	}
1321 
1322 	rdev->use_count++;
1323 
1324 	return 0;
1325 }
1326 
1327 /**
1328  * regulator_enable - enable regulator output
1329  * @regulator: regulator source
1330  *
1331  * Request that the regulator be enabled with the regulator output at
1332  * the predefined voltage or current value.  Calls to regulator_enable()
1333  * must be balanced with calls to regulator_disable().
1334  *
1335  * NOTE: the output value can be set by other drivers, boot loader or may be
1336  * hardwired in the regulator.
1337  */
1338 int regulator_enable(struct regulator *regulator)
1339 {
1340 	struct regulator_dev *rdev = regulator->rdev;
1341 	int ret = 0;
1342 
1343 	mutex_lock(&rdev->mutex);
1344 	ret = _regulator_enable(rdev);
1345 	mutex_unlock(&rdev->mutex);
1346 	return ret;
1347 }
1348 EXPORT_SYMBOL_GPL(regulator_enable);
1349 
1350 /* locks held by regulator_disable() */
1351 static int _regulator_disable(struct regulator_dev *rdev)
1352 {
1353 	int ret = 0;
1354 
1355 	if (WARN(rdev->use_count <= 0,
1356 			"unbalanced disables for %s\n",
1357 			rdev_get_name(rdev)))
1358 		return -EIO;
1359 
1360 	/* are we the last user and permitted to disable ? */
1361 	if (rdev->use_count == 1 &&
1362 	    (rdev->constraints && !rdev->constraints->always_on)) {
1363 
1364 		/* we are last user */
1365 		if (_regulator_can_change_status(rdev) &&
1366 		    rdev->desc->ops->disable) {
1367 			ret = rdev->desc->ops->disable(rdev);
1368 			if (ret < 0) {
1369 				printk(KERN_ERR "%s: failed to disable %s\n",
1370 				       __func__, rdev_get_name(rdev));
1371 				return ret;
1372 			}
1373 
1374 			_notifier_call_chain(rdev, REGULATOR_EVENT_DISABLE,
1375 					     NULL);
1376 		}
1377 
1378 		/* decrease our supplies ref count and disable if required */
1379 		if (rdev->supply)
1380 			_regulator_disable(rdev->supply);
1381 
1382 		rdev->use_count = 0;
1383 	} else if (rdev->use_count > 1) {
1384 
1385 		if (rdev->constraints &&
1386 			(rdev->constraints->valid_ops_mask &
1387 			REGULATOR_CHANGE_DRMS))
1388 			drms_uA_update(rdev);
1389 
1390 		rdev->use_count--;
1391 	}
1392 	return ret;
1393 }
1394 
1395 /**
1396  * regulator_disable - disable regulator output
1397  * @regulator: regulator source
1398  *
1399  * Disable the regulator output voltage or current.  Calls to
1400  * regulator_enable() must be balanced with calls to
1401  * regulator_disable().
1402  *
1403  * NOTE: this will only disable the regulator output if no other consumer
1404  * devices have it enabled, the regulator device supports disabling and
1405  * machine constraints permit this operation.
1406  */
1407 int regulator_disable(struct regulator *regulator)
1408 {
1409 	struct regulator_dev *rdev = regulator->rdev;
1410 	int ret = 0;
1411 
1412 	mutex_lock(&rdev->mutex);
1413 	ret = _regulator_disable(rdev);
1414 	mutex_unlock(&rdev->mutex);
1415 	return ret;
1416 }
1417 EXPORT_SYMBOL_GPL(regulator_disable);
1418 
1419 /* locks held by regulator_force_disable() */
1420 static int _regulator_force_disable(struct regulator_dev *rdev)
1421 {
1422 	int ret = 0;
1423 
1424 	/* force disable */
1425 	if (rdev->desc->ops->disable) {
1426 		/* ah well, who wants to live forever... */
1427 		ret = rdev->desc->ops->disable(rdev);
1428 		if (ret < 0) {
1429 			printk(KERN_ERR "%s: failed to force disable %s\n",
1430 			       __func__, rdev_get_name(rdev));
1431 			return ret;
1432 		}
1433 		/* notify other consumers that power has been forced off */
1434 		_notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
1435 			REGULATOR_EVENT_DISABLE, NULL);
1436 	}
1437 
1438 	/* decrease our supplies ref count and disable if required */
1439 	if (rdev->supply)
1440 		_regulator_disable(rdev->supply);
1441 
1442 	rdev->use_count = 0;
1443 	return ret;
1444 }
1445 
1446 /**
1447  * regulator_force_disable - force disable regulator output
1448  * @regulator: regulator source
1449  *
1450  * Forcibly disable the regulator output voltage or current.
1451  * NOTE: this *will* disable the regulator output even if other consumer
1452  * devices have it enabled. This should be used for situations when device
1453  * damage will likely occur if the regulator is not disabled (e.g. over temp).
1454  */
1455 int regulator_force_disable(struct regulator *regulator)
1456 {
1457 	int ret;
1458 
1459 	mutex_lock(&regulator->rdev->mutex);
1460 	regulator->uA_load = 0;
1461 	ret = _regulator_force_disable(regulator->rdev);
1462 	mutex_unlock(&regulator->rdev->mutex);
1463 	return ret;
1464 }
1465 EXPORT_SYMBOL_GPL(regulator_force_disable);
1466 
1467 static int _regulator_is_enabled(struct regulator_dev *rdev)
1468 {
1469 	/* If we don't know then assume that the regulator is always on */
1470 	if (!rdev->desc->ops->is_enabled)
1471 		return 1;
1472 
1473 	return rdev->desc->ops->is_enabled(rdev);
1474 }
1475 
1476 /**
1477  * regulator_is_enabled - is the regulator output enabled
1478  * @regulator: regulator source
1479  *
1480  * Returns positive if the regulator driver backing the source/client
1481  * has requested that the device be enabled, zero if it hasn't, else a
1482  * negative errno code.
1483  *
1484  * Note that the device backing this regulator handle can have multiple
1485  * users, so it might be enabled even if regulator_enable() was never
1486  * called for this particular source.
1487  */
1488 int regulator_is_enabled(struct regulator *regulator)
1489 {
1490 	int ret;
1491 
1492 	mutex_lock(&regulator->rdev->mutex);
1493 	ret = _regulator_is_enabled(regulator->rdev);
1494 	mutex_unlock(&regulator->rdev->mutex);
1495 
1496 	return ret;
1497 }
1498 EXPORT_SYMBOL_GPL(regulator_is_enabled);
1499 
1500 /**
1501  * regulator_count_voltages - count regulator_list_voltage() selectors
1502  * @regulator: regulator source
1503  *
1504  * Returns number of selectors, or negative errno.  Selectors are
1505  * numbered starting at zero, and typically correspond to bitfields
1506  * in hardware registers.
1507  */
1508 int regulator_count_voltages(struct regulator *regulator)
1509 {
1510 	struct regulator_dev	*rdev = regulator->rdev;
1511 
1512 	return rdev->desc->n_voltages ? : -EINVAL;
1513 }
1514 EXPORT_SYMBOL_GPL(regulator_count_voltages);
1515 
1516 /**
1517  * regulator_list_voltage - enumerate supported voltages
1518  * @regulator: regulator source
1519  * @selector: identify voltage to list
1520  * Context: can sleep
1521  *
1522  * Returns a voltage that can be passed to @regulator_set_voltage(),
1523  * zero if this selector code can't be used on this system, or a
1524  * negative errno.
1525  */
1526 int regulator_list_voltage(struct regulator *regulator, unsigned selector)
1527 {
1528 	struct regulator_dev	*rdev = regulator->rdev;
1529 	struct regulator_ops	*ops = rdev->desc->ops;
1530 	int			ret;
1531 
1532 	if (!ops->list_voltage || selector >= rdev->desc->n_voltages)
1533 		return -EINVAL;
1534 
1535 	mutex_lock(&rdev->mutex);
1536 	ret = ops->list_voltage(rdev, selector);
1537 	mutex_unlock(&rdev->mutex);
1538 
1539 	if (ret > 0) {
1540 		if (ret < rdev->constraints->min_uV)
1541 			ret = 0;
1542 		else if (ret > rdev->constraints->max_uV)
1543 			ret = 0;
1544 	}
1545 
1546 	return ret;
1547 }
1548 EXPORT_SYMBOL_GPL(regulator_list_voltage);
1549 
1550 /**
1551  * regulator_is_supported_voltage - check if a voltage range can be supported
1552  *
1553  * @regulator: Regulator to check.
1554  * @min_uV: Minimum required voltage in uV.
1555  * @max_uV: Maximum required voltage in uV.
1556  *
1557  * Returns a boolean or a negative error code.
1558  */
1559 int regulator_is_supported_voltage(struct regulator *regulator,
1560 				   int min_uV, int max_uV)
1561 {
1562 	int i, voltages, ret;
1563 
1564 	ret = regulator_count_voltages(regulator);
1565 	if (ret < 0)
1566 		return ret;
1567 	voltages = ret;
1568 
1569 	for (i = 0; i < voltages; i++) {
1570 		ret = regulator_list_voltage(regulator, i);
1571 
1572 		if (ret >= min_uV && ret <= max_uV)
1573 			return 1;
1574 	}
1575 
1576 	return 0;
1577 }
1578 
1579 /**
1580  * regulator_set_voltage - set regulator output voltage
1581  * @regulator: regulator source
1582  * @min_uV: Minimum required voltage in uV
1583  * @max_uV: Maximum acceptable voltage in uV
1584  *
1585  * Sets a voltage regulator to the desired output voltage. This can be set
1586  * during any regulator state. IOW, regulator can be disabled or enabled.
1587  *
1588  * If the regulator is enabled then the voltage will change to the new value
1589  * immediately otherwise if the regulator is disabled the regulator will
1590  * output at the new voltage when enabled.
1591  *
1592  * NOTE: If the regulator is shared between several devices then the lowest
1593  * request voltage that meets the system constraints will be used.
1594  * Regulator system constraints must be set for this regulator before
1595  * calling this function otherwise this call will fail.
1596  */
1597 int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
1598 {
1599 	struct regulator_dev *rdev = regulator->rdev;
1600 	int ret;
1601 
1602 	mutex_lock(&rdev->mutex);
1603 
1604 	/* sanity check */
1605 	if (!rdev->desc->ops->set_voltage) {
1606 		ret = -EINVAL;
1607 		goto out;
1608 	}
1609 
1610 	/* constraints check */
1611 	ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
1612 	if (ret < 0)
1613 		goto out;
1614 	regulator->min_uV = min_uV;
1615 	regulator->max_uV = max_uV;
1616 	ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV);
1617 
1618 out:
1619 	_notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE, NULL);
1620 	mutex_unlock(&rdev->mutex);
1621 	return ret;
1622 }
1623 EXPORT_SYMBOL_GPL(regulator_set_voltage);
1624 
1625 static int _regulator_get_voltage(struct regulator_dev *rdev)
1626 {
1627 	/* sanity check */
1628 	if (rdev->desc->ops->get_voltage)
1629 		return rdev->desc->ops->get_voltage(rdev);
1630 	else
1631 		return -EINVAL;
1632 }
1633 
1634 /**
1635  * regulator_get_voltage - get regulator output voltage
1636  * @regulator: regulator source
1637  *
1638  * This returns the current regulator voltage in uV.
1639  *
1640  * NOTE: If the regulator is disabled it will return the voltage value. This
1641  * function should not be used to determine regulator state.
1642  */
1643 int regulator_get_voltage(struct regulator *regulator)
1644 {
1645 	int ret;
1646 
1647 	mutex_lock(&regulator->rdev->mutex);
1648 
1649 	ret = _regulator_get_voltage(regulator->rdev);
1650 
1651 	mutex_unlock(&regulator->rdev->mutex);
1652 
1653 	return ret;
1654 }
1655 EXPORT_SYMBOL_GPL(regulator_get_voltage);
1656 
1657 /**
1658  * regulator_set_current_limit - set regulator output current limit
1659  * @regulator: regulator source
1660  * @min_uA: Minimuum supported current in uA
1661  * @max_uA: Maximum supported current in uA
1662  *
1663  * Sets current sink to the desired output current. This can be set during
1664  * any regulator state. IOW, regulator can be disabled or enabled.
1665  *
1666  * If the regulator is enabled then the current will change to the new value
1667  * immediately otherwise if the regulator is disabled the regulator will
1668  * output at the new current when enabled.
1669  *
1670  * NOTE: Regulator system constraints must be set for this regulator before
1671  * calling this function otherwise this call will fail.
1672  */
1673 int regulator_set_current_limit(struct regulator *regulator,
1674 			       int min_uA, int max_uA)
1675 {
1676 	struct regulator_dev *rdev = regulator->rdev;
1677 	int ret;
1678 
1679 	mutex_lock(&rdev->mutex);
1680 
1681 	/* sanity check */
1682 	if (!rdev->desc->ops->set_current_limit) {
1683 		ret = -EINVAL;
1684 		goto out;
1685 	}
1686 
1687 	/* constraints check */
1688 	ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
1689 	if (ret < 0)
1690 		goto out;
1691 
1692 	ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
1693 out:
1694 	mutex_unlock(&rdev->mutex);
1695 	return ret;
1696 }
1697 EXPORT_SYMBOL_GPL(regulator_set_current_limit);
1698 
1699 static int _regulator_get_current_limit(struct regulator_dev *rdev)
1700 {
1701 	int ret;
1702 
1703 	mutex_lock(&rdev->mutex);
1704 
1705 	/* sanity check */
1706 	if (!rdev->desc->ops->get_current_limit) {
1707 		ret = -EINVAL;
1708 		goto out;
1709 	}
1710 
1711 	ret = rdev->desc->ops->get_current_limit(rdev);
1712 out:
1713 	mutex_unlock(&rdev->mutex);
1714 	return ret;
1715 }
1716 
1717 /**
1718  * regulator_get_current_limit - get regulator output current
1719  * @regulator: regulator source
1720  *
1721  * This returns the current supplied by the specified current sink in uA.
1722  *
1723  * NOTE: If the regulator is disabled it will return the current value. This
1724  * function should not be used to determine regulator state.
1725  */
1726 int regulator_get_current_limit(struct regulator *regulator)
1727 {
1728 	return _regulator_get_current_limit(regulator->rdev);
1729 }
1730 EXPORT_SYMBOL_GPL(regulator_get_current_limit);
1731 
1732 /**
1733  * regulator_set_mode - set regulator operating mode
1734  * @regulator: regulator source
1735  * @mode: operating mode - one of the REGULATOR_MODE constants
1736  *
1737  * Set regulator operating mode to increase regulator efficiency or improve
1738  * regulation performance.
1739  *
1740  * NOTE: Regulator system constraints must be set for this regulator before
1741  * calling this function otherwise this call will fail.
1742  */
1743 int regulator_set_mode(struct regulator *regulator, unsigned int mode)
1744 {
1745 	struct regulator_dev *rdev = regulator->rdev;
1746 	int ret;
1747 	int regulator_curr_mode;
1748 
1749 	mutex_lock(&rdev->mutex);
1750 
1751 	/* sanity check */
1752 	if (!rdev->desc->ops->set_mode) {
1753 		ret = -EINVAL;
1754 		goto out;
1755 	}
1756 
1757 	/* return if the same mode is requested */
1758 	if (rdev->desc->ops->get_mode) {
1759 		regulator_curr_mode = rdev->desc->ops->get_mode(rdev);
1760 		if (regulator_curr_mode == mode) {
1761 			ret = 0;
1762 			goto out;
1763 		}
1764 	}
1765 
1766 	/* constraints check */
1767 	ret = regulator_check_mode(rdev, mode);
1768 	if (ret < 0)
1769 		goto out;
1770 
1771 	ret = rdev->desc->ops->set_mode(rdev, mode);
1772 out:
1773 	mutex_unlock(&rdev->mutex);
1774 	return ret;
1775 }
1776 EXPORT_SYMBOL_GPL(regulator_set_mode);
1777 
1778 static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
1779 {
1780 	int ret;
1781 
1782 	mutex_lock(&rdev->mutex);
1783 
1784 	/* sanity check */
1785 	if (!rdev->desc->ops->get_mode) {
1786 		ret = -EINVAL;
1787 		goto out;
1788 	}
1789 
1790 	ret = rdev->desc->ops->get_mode(rdev);
1791 out:
1792 	mutex_unlock(&rdev->mutex);
1793 	return ret;
1794 }
1795 
1796 /**
1797  * regulator_get_mode - get regulator operating mode
1798  * @regulator: regulator source
1799  *
1800  * Get the current regulator operating mode.
1801  */
1802 unsigned int regulator_get_mode(struct regulator *regulator)
1803 {
1804 	return _regulator_get_mode(regulator->rdev);
1805 }
1806 EXPORT_SYMBOL_GPL(regulator_get_mode);
1807 
1808 /**
1809  * regulator_set_optimum_mode - set regulator optimum operating mode
1810  * @regulator: regulator source
1811  * @uA_load: load current
1812  *
1813  * Notifies the regulator core of a new device load. This is then used by
1814  * DRMS (if enabled by constraints) to set the most efficient regulator
1815  * operating mode for the new regulator loading.
1816  *
1817  * Consumer devices notify their supply regulator of the maximum power
1818  * they will require (can be taken from device datasheet in the power
1819  * consumption tables) when they change operational status and hence power
1820  * state. Examples of operational state changes that can affect power
1821  * consumption are :-
1822  *
1823  *    o Device is opened / closed.
1824  *    o Device I/O is about to begin or has just finished.
1825  *    o Device is idling in between work.
1826  *
1827  * This information is also exported via sysfs to userspace.
1828  *
1829  * DRMS will sum the total requested load on the regulator and change
1830  * to the most efficient operating mode if platform constraints allow.
1831  *
1832  * Returns the new regulator mode or error.
1833  */
1834 int regulator_set_optimum_mode(struct regulator *regulator, int uA_load)
1835 {
1836 	struct regulator_dev *rdev = regulator->rdev;
1837 	struct regulator *consumer;
1838 	int ret, output_uV, input_uV, total_uA_load = 0;
1839 	unsigned int mode;
1840 
1841 	mutex_lock(&rdev->mutex);
1842 
1843 	regulator->uA_load = uA_load;
1844 	ret = regulator_check_drms(rdev);
1845 	if (ret < 0)
1846 		goto out;
1847 	ret = -EINVAL;
1848 
1849 	/* sanity check */
1850 	if (!rdev->desc->ops->get_optimum_mode)
1851 		goto out;
1852 
1853 	/* get output voltage */
1854 	output_uV = rdev->desc->ops->get_voltage(rdev);
1855 	if (output_uV <= 0) {
1856 		printk(KERN_ERR "%s: invalid output voltage found for %s\n",
1857 			__func__, rdev_get_name(rdev));
1858 		goto out;
1859 	}
1860 
1861 	/* get input voltage */
1862 	if (rdev->supply && rdev->supply->desc->ops->get_voltage)
1863 		input_uV = rdev->supply->desc->ops->get_voltage(rdev->supply);
1864 	else
1865 		input_uV = rdev->constraints->input_uV;
1866 	if (input_uV <= 0) {
1867 		printk(KERN_ERR "%s: invalid input voltage found for %s\n",
1868 			__func__, rdev_get_name(rdev));
1869 		goto out;
1870 	}
1871 
1872 	/* calc total requested load for this regulator */
1873 	list_for_each_entry(consumer, &rdev->consumer_list, list)
1874 		total_uA_load += consumer->uA_load;
1875 
1876 	mode = rdev->desc->ops->get_optimum_mode(rdev,
1877 						 input_uV, output_uV,
1878 						 total_uA_load);
1879 	ret = regulator_check_mode(rdev, mode);
1880 	if (ret < 0) {
1881 		printk(KERN_ERR "%s: failed to get optimum mode for %s @"
1882 			" %d uA %d -> %d uV\n", __func__, rdev_get_name(rdev),
1883 			total_uA_load, input_uV, output_uV);
1884 		goto out;
1885 	}
1886 
1887 	ret = rdev->desc->ops->set_mode(rdev, mode);
1888 	if (ret < 0) {
1889 		printk(KERN_ERR "%s: failed to set optimum mode %x for %s\n",
1890 			__func__, mode, rdev_get_name(rdev));
1891 		goto out;
1892 	}
1893 	ret = mode;
1894 out:
1895 	mutex_unlock(&rdev->mutex);
1896 	return ret;
1897 }
1898 EXPORT_SYMBOL_GPL(regulator_set_optimum_mode);
1899 
1900 /**
1901  * regulator_register_notifier - register regulator event notifier
1902  * @regulator: regulator source
1903  * @nb: notifier block
1904  *
1905  * Register notifier block to receive regulator events.
1906  */
1907 int regulator_register_notifier(struct regulator *regulator,
1908 			      struct notifier_block *nb)
1909 {
1910 	return blocking_notifier_chain_register(&regulator->rdev->notifier,
1911 						nb);
1912 }
1913 EXPORT_SYMBOL_GPL(regulator_register_notifier);
1914 
1915 /**
1916  * regulator_unregister_notifier - unregister regulator event notifier
1917  * @regulator: regulator source
1918  * @nb: notifier block
1919  *
1920  * Unregister regulator event notifier block.
1921  */
1922 int regulator_unregister_notifier(struct regulator *regulator,
1923 				struct notifier_block *nb)
1924 {
1925 	return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
1926 						  nb);
1927 }
1928 EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
1929 
1930 /* notify regulator consumers and downstream regulator consumers.
1931  * Note mutex must be held by caller.
1932  */
1933 static void _notifier_call_chain(struct regulator_dev *rdev,
1934 				  unsigned long event, void *data)
1935 {
1936 	struct regulator_dev *_rdev;
1937 
1938 	/* call rdev chain first */
1939 	blocking_notifier_call_chain(&rdev->notifier, event, NULL);
1940 
1941 	/* now notify regulator we supply */
1942 	list_for_each_entry(_rdev, &rdev->supply_list, slist) {
1943 		mutex_lock(&_rdev->mutex);
1944 		_notifier_call_chain(_rdev, event, data);
1945 		mutex_unlock(&_rdev->mutex);
1946 	}
1947 }
1948 
1949 /**
1950  * regulator_bulk_get - get multiple regulator consumers
1951  *
1952  * @dev:           Device to supply
1953  * @num_consumers: Number of consumers to register
1954  * @consumers:     Configuration of consumers; clients are stored here.
1955  *
1956  * @return 0 on success, an errno on failure.
1957  *
1958  * This helper function allows drivers to get several regulator
1959  * consumers in one operation.  If any of the regulators cannot be
1960  * acquired then any regulators that were allocated will be freed
1961  * before returning to the caller.
1962  */
1963 int regulator_bulk_get(struct device *dev, int num_consumers,
1964 		       struct regulator_bulk_data *consumers)
1965 {
1966 	int i;
1967 	int ret;
1968 
1969 	for (i = 0; i < num_consumers; i++)
1970 		consumers[i].consumer = NULL;
1971 
1972 	for (i = 0; i < num_consumers; i++) {
1973 		consumers[i].consumer = regulator_get(dev,
1974 						      consumers[i].supply);
1975 		if (IS_ERR(consumers[i].consumer)) {
1976 			ret = PTR_ERR(consumers[i].consumer);
1977 			dev_err(dev, "Failed to get supply '%s': %d\n",
1978 				consumers[i].supply, ret);
1979 			consumers[i].consumer = NULL;
1980 			goto err;
1981 		}
1982 	}
1983 
1984 	return 0;
1985 
1986 err:
1987 	for (i = 0; i < num_consumers && consumers[i].consumer; i++)
1988 		regulator_put(consumers[i].consumer);
1989 
1990 	return ret;
1991 }
1992 EXPORT_SYMBOL_GPL(regulator_bulk_get);
1993 
1994 /**
1995  * regulator_bulk_enable - enable multiple regulator consumers
1996  *
1997  * @num_consumers: Number of consumers
1998  * @consumers:     Consumer data; clients are stored here.
1999  * @return         0 on success, an errno on failure
2000  *
2001  * This convenience API allows consumers to enable multiple regulator
2002  * clients in a single API call.  If any consumers cannot be enabled
2003  * then any others that were enabled will be disabled again prior to
2004  * return.
2005  */
2006 int regulator_bulk_enable(int num_consumers,
2007 			  struct regulator_bulk_data *consumers)
2008 {
2009 	int i;
2010 	int ret;
2011 
2012 	for (i = 0; i < num_consumers; i++) {
2013 		ret = regulator_enable(consumers[i].consumer);
2014 		if (ret != 0)
2015 			goto err;
2016 	}
2017 
2018 	return 0;
2019 
2020 err:
2021 	printk(KERN_ERR "Failed to enable %s: %d\n", consumers[i].supply, ret);
2022 	for (--i; i >= 0; --i)
2023 		regulator_disable(consumers[i].consumer);
2024 
2025 	return ret;
2026 }
2027 EXPORT_SYMBOL_GPL(regulator_bulk_enable);
2028 
2029 /**
2030  * regulator_bulk_disable - disable multiple regulator consumers
2031  *
2032  * @num_consumers: Number of consumers
2033  * @consumers:     Consumer data; clients are stored here.
2034  * @return         0 on success, an errno on failure
2035  *
2036  * This convenience API allows consumers to disable multiple regulator
2037  * clients in a single API call.  If any consumers cannot be enabled
2038  * then any others that were disabled will be disabled again prior to
2039  * return.
2040  */
2041 int regulator_bulk_disable(int num_consumers,
2042 			   struct regulator_bulk_data *consumers)
2043 {
2044 	int i;
2045 	int ret;
2046 
2047 	for (i = 0; i < num_consumers; i++) {
2048 		ret = regulator_disable(consumers[i].consumer);
2049 		if (ret != 0)
2050 			goto err;
2051 	}
2052 
2053 	return 0;
2054 
2055 err:
2056 	printk(KERN_ERR "Failed to disable %s: %d\n", consumers[i].supply,
2057 	       ret);
2058 	for (--i; i >= 0; --i)
2059 		regulator_enable(consumers[i].consumer);
2060 
2061 	return ret;
2062 }
2063 EXPORT_SYMBOL_GPL(regulator_bulk_disable);
2064 
2065 /**
2066  * regulator_bulk_free - free multiple regulator consumers
2067  *
2068  * @num_consumers: Number of consumers
2069  * @consumers:     Consumer data; clients are stored here.
2070  *
2071  * This convenience API allows consumers to free multiple regulator
2072  * clients in a single API call.
2073  */
2074 void regulator_bulk_free(int num_consumers,
2075 			 struct regulator_bulk_data *consumers)
2076 {
2077 	int i;
2078 
2079 	for (i = 0; i < num_consumers; i++) {
2080 		regulator_put(consumers[i].consumer);
2081 		consumers[i].consumer = NULL;
2082 	}
2083 }
2084 EXPORT_SYMBOL_GPL(regulator_bulk_free);
2085 
2086 /**
2087  * regulator_notifier_call_chain - call regulator event notifier
2088  * @rdev: regulator source
2089  * @event: notifier block
2090  * @data: callback-specific data.
2091  *
2092  * Called by regulator drivers to notify clients a regulator event has
2093  * occurred. We also notify regulator clients downstream.
2094  * Note lock must be held by caller.
2095  */
2096 int regulator_notifier_call_chain(struct regulator_dev *rdev,
2097 				  unsigned long event, void *data)
2098 {
2099 	_notifier_call_chain(rdev, event, data);
2100 	return NOTIFY_DONE;
2101 
2102 }
2103 EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
2104 
2105 /**
2106  * regulator_mode_to_status - convert a regulator mode into a status
2107  *
2108  * @mode: Mode to convert
2109  *
2110  * Convert a regulator mode into a status.
2111  */
2112 int regulator_mode_to_status(unsigned int mode)
2113 {
2114 	switch (mode) {
2115 	case REGULATOR_MODE_FAST:
2116 		return REGULATOR_STATUS_FAST;
2117 	case REGULATOR_MODE_NORMAL:
2118 		return REGULATOR_STATUS_NORMAL;
2119 	case REGULATOR_MODE_IDLE:
2120 		return REGULATOR_STATUS_IDLE;
2121 	case REGULATOR_STATUS_STANDBY:
2122 		return REGULATOR_STATUS_STANDBY;
2123 	default:
2124 		return 0;
2125 	}
2126 }
2127 EXPORT_SYMBOL_GPL(regulator_mode_to_status);
2128 
2129 /*
2130  * To avoid cluttering sysfs (and memory) with useless state, only
2131  * create attributes that can be meaningfully displayed.
2132  */
2133 static int add_regulator_attributes(struct regulator_dev *rdev)
2134 {
2135 	struct device		*dev = &rdev->dev;
2136 	struct regulator_ops	*ops = rdev->desc->ops;
2137 	int			status = 0;
2138 
2139 	/* some attributes need specific methods to be displayed */
2140 	if (ops->get_voltage) {
2141 		status = device_create_file(dev, &dev_attr_microvolts);
2142 		if (status < 0)
2143 			return status;
2144 	}
2145 	if (ops->get_current_limit) {
2146 		status = device_create_file(dev, &dev_attr_microamps);
2147 		if (status < 0)
2148 			return status;
2149 	}
2150 	if (ops->get_mode) {
2151 		status = device_create_file(dev, &dev_attr_opmode);
2152 		if (status < 0)
2153 			return status;
2154 	}
2155 	if (ops->is_enabled) {
2156 		status = device_create_file(dev, &dev_attr_state);
2157 		if (status < 0)
2158 			return status;
2159 	}
2160 	if (ops->get_status) {
2161 		status = device_create_file(dev, &dev_attr_status);
2162 		if (status < 0)
2163 			return status;
2164 	}
2165 
2166 	/* some attributes are type-specific */
2167 	if (rdev->desc->type == REGULATOR_CURRENT) {
2168 		status = device_create_file(dev, &dev_attr_requested_microamps);
2169 		if (status < 0)
2170 			return status;
2171 	}
2172 
2173 	/* all the other attributes exist to support constraints;
2174 	 * don't show them if there are no constraints, or if the
2175 	 * relevant supporting methods are missing.
2176 	 */
2177 	if (!rdev->constraints)
2178 		return status;
2179 
2180 	/* constraints need specific supporting methods */
2181 	if (ops->set_voltage) {
2182 		status = device_create_file(dev, &dev_attr_min_microvolts);
2183 		if (status < 0)
2184 			return status;
2185 		status = device_create_file(dev, &dev_attr_max_microvolts);
2186 		if (status < 0)
2187 			return status;
2188 	}
2189 	if (ops->set_current_limit) {
2190 		status = device_create_file(dev, &dev_attr_min_microamps);
2191 		if (status < 0)
2192 			return status;
2193 		status = device_create_file(dev, &dev_attr_max_microamps);
2194 		if (status < 0)
2195 			return status;
2196 	}
2197 
2198 	/* suspend mode constraints need multiple supporting methods */
2199 	if (!(ops->set_suspend_enable && ops->set_suspend_disable))
2200 		return status;
2201 
2202 	status = device_create_file(dev, &dev_attr_suspend_standby_state);
2203 	if (status < 0)
2204 		return status;
2205 	status = device_create_file(dev, &dev_attr_suspend_mem_state);
2206 	if (status < 0)
2207 		return status;
2208 	status = device_create_file(dev, &dev_attr_suspend_disk_state);
2209 	if (status < 0)
2210 		return status;
2211 
2212 	if (ops->set_suspend_voltage) {
2213 		status = device_create_file(dev,
2214 				&dev_attr_suspend_standby_microvolts);
2215 		if (status < 0)
2216 			return status;
2217 		status = device_create_file(dev,
2218 				&dev_attr_suspend_mem_microvolts);
2219 		if (status < 0)
2220 			return status;
2221 		status = device_create_file(dev,
2222 				&dev_attr_suspend_disk_microvolts);
2223 		if (status < 0)
2224 			return status;
2225 	}
2226 
2227 	if (ops->set_suspend_mode) {
2228 		status = device_create_file(dev,
2229 				&dev_attr_suspend_standby_mode);
2230 		if (status < 0)
2231 			return status;
2232 		status = device_create_file(dev,
2233 				&dev_attr_suspend_mem_mode);
2234 		if (status < 0)
2235 			return status;
2236 		status = device_create_file(dev,
2237 				&dev_attr_suspend_disk_mode);
2238 		if (status < 0)
2239 			return status;
2240 	}
2241 
2242 	return status;
2243 }
2244 
2245 /**
2246  * regulator_register - register regulator
2247  * @regulator_desc: regulator to register
2248  * @dev: struct device for the regulator
2249  * @init_data: platform provided init data, passed through by driver
2250  * @driver_data: private regulator data
2251  *
2252  * Called by regulator drivers to register a regulator.
2253  * Returns 0 on success.
2254  */
2255 struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc,
2256 	struct device *dev, struct regulator_init_data *init_data,
2257 	void *driver_data)
2258 {
2259 	static atomic_t regulator_no = ATOMIC_INIT(0);
2260 	struct regulator_dev *rdev;
2261 	int ret, i;
2262 
2263 	if (regulator_desc == NULL)
2264 		return ERR_PTR(-EINVAL);
2265 
2266 	if (regulator_desc->name == NULL || regulator_desc->ops == NULL)
2267 		return ERR_PTR(-EINVAL);
2268 
2269 	if (regulator_desc->type != REGULATOR_VOLTAGE &&
2270 	    regulator_desc->type != REGULATOR_CURRENT)
2271 		return ERR_PTR(-EINVAL);
2272 
2273 	if (!init_data)
2274 		return ERR_PTR(-EINVAL);
2275 
2276 	rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
2277 	if (rdev == NULL)
2278 		return ERR_PTR(-ENOMEM);
2279 
2280 	mutex_lock(&regulator_list_mutex);
2281 
2282 	mutex_init(&rdev->mutex);
2283 	rdev->reg_data = driver_data;
2284 	rdev->owner = regulator_desc->owner;
2285 	rdev->desc = regulator_desc;
2286 	INIT_LIST_HEAD(&rdev->consumer_list);
2287 	INIT_LIST_HEAD(&rdev->supply_list);
2288 	INIT_LIST_HEAD(&rdev->list);
2289 	INIT_LIST_HEAD(&rdev->slist);
2290 	BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
2291 
2292 	/* preform any regulator specific init */
2293 	if (init_data->regulator_init) {
2294 		ret = init_data->regulator_init(rdev->reg_data);
2295 		if (ret < 0)
2296 			goto clean;
2297 	}
2298 
2299 	/* register with sysfs */
2300 	rdev->dev.class = &regulator_class;
2301 	rdev->dev.parent = dev;
2302 	dev_set_name(&rdev->dev, "regulator.%d",
2303 		     atomic_inc_return(&regulator_no) - 1);
2304 	ret = device_register(&rdev->dev);
2305 	if (ret != 0)
2306 		goto clean;
2307 
2308 	dev_set_drvdata(&rdev->dev, rdev);
2309 
2310 	/* set regulator constraints */
2311 	ret = set_machine_constraints(rdev, &init_data->constraints);
2312 	if (ret < 0)
2313 		goto scrub;
2314 
2315 	/* add attributes supported by this regulator */
2316 	ret = add_regulator_attributes(rdev);
2317 	if (ret < 0)
2318 		goto scrub;
2319 
2320 	/* set supply regulator if it exists */
2321 	if (init_data->supply_regulator && init_data->supply_regulator_dev) {
2322 		dev_err(dev,
2323 			"Supply regulator specified by both name and dev\n");
2324 		goto scrub;
2325 	}
2326 
2327 	if (init_data->supply_regulator) {
2328 		struct regulator_dev *r;
2329 		int found = 0;
2330 
2331 		list_for_each_entry(r, &regulator_list, list) {
2332 			if (strcmp(rdev_get_name(r),
2333 				   init_data->supply_regulator) == 0) {
2334 				found = 1;
2335 				break;
2336 			}
2337 		}
2338 
2339 		if (!found) {
2340 			dev_err(dev, "Failed to find supply %s\n",
2341 				init_data->supply_regulator);
2342 			goto scrub;
2343 		}
2344 
2345 		ret = set_supply(rdev, r);
2346 		if (ret < 0)
2347 			goto scrub;
2348 	}
2349 
2350 	if (init_data->supply_regulator_dev) {
2351 		dev_warn(dev, "Uses supply_regulator_dev instead of regulator_supply\n");
2352 		ret = set_supply(rdev,
2353 			dev_get_drvdata(init_data->supply_regulator_dev));
2354 		if (ret < 0)
2355 			goto scrub;
2356 	}
2357 
2358 	/* add consumers devices */
2359 	for (i = 0; i < init_data->num_consumer_supplies; i++) {
2360 		ret = set_consumer_device_supply(rdev,
2361 			init_data->consumer_supplies[i].dev,
2362 			init_data->consumer_supplies[i].dev_name,
2363 			init_data->consumer_supplies[i].supply);
2364 		if (ret < 0)
2365 			goto unset_supplies;
2366 	}
2367 
2368 	list_add(&rdev->list, &regulator_list);
2369 out:
2370 	mutex_unlock(&regulator_list_mutex);
2371 	return rdev;
2372 
2373 unset_supplies:
2374 	unset_regulator_supplies(rdev);
2375 
2376 scrub:
2377 	device_unregister(&rdev->dev);
2378 	/* device core frees rdev */
2379 	rdev = ERR_PTR(ret);
2380 	goto out;
2381 
2382 clean:
2383 	kfree(rdev);
2384 	rdev = ERR_PTR(ret);
2385 	goto out;
2386 }
2387 EXPORT_SYMBOL_GPL(regulator_register);
2388 
2389 /**
2390  * regulator_unregister - unregister regulator
2391  * @rdev: regulator to unregister
2392  *
2393  * Called by regulator drivers to unregister a regulator.
2394  */
2395 void regulator_unregister(struct regulator_dev *rdev)
2396 {
2397 	if (rdev == NULL)
2398 		return;
2399 
2400 	mutex_lock(&regulator_list_mutex);
2401 	WARN_ON(rdev->open_count);
2402 	unset_regulator_supplies(rdev);
2403 	list_del(&rdev->list);
2404 	if (rdev->supply)
2405 		sysfs_remove_link(&rdev->dev.kobj, "supply");
2406 	device_unregister(&rdev->dev);
2407 	mutex_unlock(&regulator_list_mutex);
2408 }
2409 EXPORT_SYMBOL_GPL(regulator_unregister);
2410 
2411 /**
2412  * regulator_suspend_prepare - prepare regulators for system wide suspend
2413  * @state: system suspend state
2414  *
2415  * Configure each regulator with it's suspend operating parameters for state.
2416  * This will usually be called by machine suspend code prior to supending.
2417  */
2418 int regulator_suspend_prepare(suspend_state_t state)
2419 {
2420 	struct regulator_dev *rdev;
2421 	int ret = 0;
2422 
2423 	/* ON is handled by regulator active state */
2424 	if (state == PM_SUSPEND_ON)
2425 		return -EINVAL;
2426 
2427 	mutex_lock(&regulator_list_mutex);
2428 	list_for_each_entry(rdev, &regulator_list, list) {
2429 
2430 		mutex_lock(&rdev->mutex);
2431 		ret = suspend_prepare(rdev, state);
2432 		mutex_unlock(&rdev->mutex);
2433 
2434 		if (ret < 0) {
2435 			printk(KERN_ERR "%s: failed to prepare %s\n",
2436 				__func__, rdev_get_name(rdev));
2437 			goto out;
2438 		}
2439 	}
2440 out:
2441 	mutex_unlock(&regulator_list_mutex);
2442 	return ret;
2443 }
2444 EXPORT_SYMBOL_GPL(regulator_suspend_prepare);
2445 
2446 /**
2447  * regulator_has_full_constraints - the system has fully specified constraints
2448  *
2449  * Calling this function will cause the regulator API to disable all
2450  * regulators which have a zero use count and don't have an always_on
2451  * constraint in a late_initcall.
2452  *
2453  * The intention is that this will become the default behaviour in a
2454  * future kernel release so users are encouraged to use this facility
2455  * now.
2456  */
2457 void regulator_has_full_constraints(void)
2458 {
2459 	has_full_constraints = 1;
2460 }
2461 EXPORT_SYMBOL_GPL(regulator_has_full_constraints);
2462 
2463 /**
2464  * rdev_get_drvdata - get rdev regulator driver data
2465  * @rdev: regulator
2466  *
2467  * Get rdev regulator driver private data. This call can be used in the
2468  * regulator driver context.
2469  */
2470 void *rdev_get_drvdata(struct regulator_dev *rdev)
2471 {
2472 	return rdev->reg_data;
2473 }
2474 EXPORT_SYMBOL_GPL(rdev_get_drvdata);
2475 
2476 /**
2477  * regulator_get_drvdata - get regulator driver data
2478  * @regulator: regulator
2479  *
2480  * Get regulator driver private data. This call can be used in the consumer
2481  * driver context when non API regulator specific functions need to be called.
2482  */
2483 void *regulator_get_drvdata(struct regulator *regulator)
2484 {
2485 	return regulator->rdev->reg_data;
2486 }
2487 EXPORT_SYMBOL_GPL(regulator_get_drvdata);
2488 
2489 /**
2490  * regulator_set_drvdata - set regulator driver data
2491  * @regulator: regulator
2492  * @data: data
2493  */
2494 void regulator_set_drvdata(struct regulator *regulator, void *data)
2495 {
2496 	regulator->rdev->reg_data = data;
2497 }
2498 EXPORT_SYMBOL_GPL(regulator_set_drvdata);
2499 
2500 /**
2501  * regulator_get_id - get regulator ID
2502  * @rdev: regulator
2503  */
2504 int rdev_get_id(struct regulator_dev *rdev)
2505 {
2506 	return rdev->desc->id;
2507 }
2508 EXPORT_SYMBOL_GPL(rdev_get_id);
2509 
2510 struct device *rdev_get_dev(struct regulator_dev *rdev)
2511 {
2512 	return &rdev->dev;
2513 }
2514 EXPORT_SYMBOL_GPL(rdev_get_dev);
2515 
2516 void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
2517 {
2518 	return reg_init_data->driver_data;
2519 }
2520 EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
2521 
2522 static int __init regulator_init(void)
2523 {
2524 	int ret;
2525 
2526 	printk(KERN_INFO "regulator: core version %s\n", REGULATOR_VERSION);
2527 
2528 	ret = class_register(&regulator_class);
2529 
2530 	regulator_dummy_init();
2531 
2532 	return ret;
2533 }
2534 
2535 /* init early to allow our consumers to complete system booting */
2536 core_initcall(regulator_init);
2537 
2538 static int __init regulator_init_complete(void)
2539 {
2540 	struct regulator_dev *rdev;
2541 	struct regulator_ops *ops;
2542 	struct regulation_constraints *c;
2543 	int enabled, ret;
2544 	const char *name;
2545 
2546 	mutex_lock(&regulator_list_mutex);
2547 
2548 	/* If we have a full configuration then disable any regulators
2549 	 * which are not in use or always_on.  This will become the
2550 	 * default behaviour in the future.
2551 	 */
2552 	list_for_each_entry(rdev, &regulator_list, list) {
2553 		ops = rdev->desc->ops;
2554 		c = rdev->constraints;
2555 
2556 		name = rdev_get_name(rdev);
2557 
2558 		if (!ops->disable || (c && c->always_on))
2559 			continue;
2560 
2561 		mutex_lock(&rdev->mutex);
2562 
2563 		if (rdev->use_count)
2564 			goto unlock;
2565 
2566 		/* If we can't read the status assume it's on. */
2567 		if (ops->is_enabled)
2568 			enabled = ops->is_enabled(rdev);
2569 		else
2570 			enabled = 1;
2571 
2572 		if (!enabled)
2573 			goto unlock;
2574 
2575 		if (has_full_constraints) {
2576 			/* We log since this may kill the system if it
2577 			 * goes wrong. */
2578 			printk(KERN_INFO "%s: disabling %s\n",
2579 			       __func__, name);
2580 			ret = ops->disable(rdev);
2581 			if (ret != 0) {
2582 				printk(KERN_ERR
2583 				       "%s: couldn't disable %s: %d\n",
2584 				       __func__, name, ret);
2585 			}
2586 		} else {
2587 			/* The intention is that in future we will
2588 			 * assume that full constraints are provided
2589 			 * so warn even if we aren't going to do
2590 			 * anything here.
2591 			 */
2592 			printk(KERN_WARNING
2593 			       "%s: incomplete constraints, leaving %s on\n",
2594 			       __func__, name);
2595 		}
2596 
2597 unlock:
2598 		mutex_unlock(&rdev->mutex);
2599 	}
2600 
2601 	mutex_unlock(&regulator_list_mutex);
2602 
2603 	return 0;
2604 }
2605 late_initcall(regulator_init_complete);
2606