summaryrefslogtreecommitdiffstats
path: root/drivers/regulator/of_regulator.c
blob: 06c0b15fe4c08782e0d2c14745ac72e7849ce4f8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * OF helpers for regulator framework
 *
 * Copyright (C) 2011 Texas Instruments, Inc.
 * Rajendra Nayak <rnayak@ti.com>
 */

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/regulator/machine.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/of_regulator.h>

#include "internal.h"

static const char *const regulator_states[PM_SUSPEND_MAX + 1] = {
	[PM_SUSPEND_STANDBY]	= "regulator-state-standby",
	[PM_SUSPEND_MEM]	= "regulator-state-mem",
	[PM_SUSPEND_MAX]	= "regulator-state-disk",
};

static int of_get_regulation_constraints(struct device *dev,
					struct device_node *np,
					struct regulator_init_data **init_data,
					const struct regulator_desc *desc)
{
	struct regulation_constraints *constraints = &(*init_data)->constraints;
	struct regulator_state *suspend_state;
	struct device_node *suspend_np;
	unsigned int mode;
	int ret, i, len;
	int n_phandles;
	u32 pval;

	n_phandles = of_count_phandle_with_args(np, "regulator-coupled-with",
						NULL);
	n_phandles = max(n_phandles, 0);

	constraints->name = of_get_property(np, "regulator-name", NULL);

	if (!of_property_read_u32(np, "regulator-min-microvolt", &pval))
		constraints->min_uV = pval;

	if (!of_property_read_u32(np, "regulator-max-microvolt", &pval))
		constraints->max_uV = pval;

	/* Voltage change possible? */
	if (constraints->min_uV != constraints->max_uV)
		constraints->valid_ops_mask |= REGULATOR_CHANGE_VOLTAGE;

	/* Do we have a voltage range, if so try to apply it? */
	if (constraints->min_uV && constraints->max_uV)
		constraints->apply_uV = true;

	if (!of_property_read_u32(np, "regulator-microvolt-offset", &pval))
		constraints->uV_offset = pval;
	if (!of_property_read_u32(np, "regulator-min-microamp", &pval))
		constraints->min_uA = pval;
	if (!of_property_read_u32(np, "regulator-max-microamp", &pval))
		constraints->max_uA = pval;

	if (!of_property_read_u32(np, "regulator-input-current-limit-microamp",
				  &pval))
		constraints->ilim_uA = pval;

	/* Current change possible? */
	if (constraints->min_uA != constraints->max_uA)
		constraints->valid_ops_mask |= REGULATOR_CHANGE_CURRENT;

	constraints->boot_on = of_property_read_bool(np, "regulator-boot-on");
	constraints->always_on = of_property_read_bool(np, "regulator-always-on");
	if (!constraints->always_on) /* status change should be possible. */
		constraints->valid_ops_mask |= REGULATOR_CHANGE_STATUS;

	constraints->pull_down = of_property_read_bool(np, "regulator-pull-down");

	if (of_property_read_bool(np, "regulator-allow-bypass"))
		constraints->valid_ops_mask |= REGULATOR_CHANGE_BYPASS;

	if (of_property_read_bool(np, "regulator-allow-set-load"))
		constraints->valid_ops_mask |= REGULATOR_CHANGE_DRMS;

	ret = of_property_read_u32(np, "regulator-ramp-delay", &pval);
	if (!ret) {
		if (pval)
			constraints->ramp_delay = pval;
		else
			constraints->ramp_disable = true;
	}

	ret = of_property_read_u32(np, "regulator-settling-time-us", &pval);
	if (!ret)
		constraints->settling_time = pval;

	ret = of_property_read_u32(np, "regulator-settling-time-up-us", &pval);
	if (!ret)
		constraints->settling_time_up = pval;
	if (constraints->settling_time_up && constraints->settling_time) {
		pr_warn("%pOFn: ambiguous configuration for settling time, ignoring 'regulator-settling-time-up-us'\n",
			np);
		constraints->settling_time_up = 0;
	}

	ret = of_property_read_u32(np, "regulator-settling-time-down-us",
				   &pval);
	if (!ret)
		constraints->settling_time_down = pval;
	if (constraints->settling_time_down && constraints->settling_time) {
		pr_warn("%pOFn: ambiguous configuration for settling time, ignoring 'regulator-settling-time-down-us'\n",
			np);
		constraints->settling_time_down = 0;
	}

	ret = of_property_read_u32(np, "regulator-enable-ramp-delay", &pval);
	if (!ret)
		constraints->enable_time = pval;

	constraints->soft_start = of_property_read_bool(np,
					"regulator-soft-start");
	ret = of_property_read_u32(np, "regulator-active-discharge", &pval);
	if (!ret) {
		constraints->active_discharge =
				(pval) ? REGULATOR_ACTIVE_DISCHARGE_ENABLE :
					REGULATOR_ACTIVE_DISCHARGE_DISABLE;
	}

	if (!of_property_read_u32(np, "regulator-initial-mode", &pval)) {
		if (desc && desc->of_map_mode) {
			mode = desc->of_map_mode(pval);
			if (mode == REGULATOR_MODE_INVALID)
				pr_err("%pOFn: invalid mode %u\n", np, pval);
			else
				constraints->initial_mode = mode;
		} else {
			pr_warn("%pOFn: mapping for mode %d not defined\n",
				np, pval);
		}
	}

	len = of_property_count_elems_of_size(np, "regulator-allowed-modes",
						sizeof(u32));
	if (len > 0) {
		if (desc && desc->of_map_mode) {
			for (i = 0; i < len; i++) {
				ret = of_property_read_u32_index(np,
					"regulator-allowed-modes", i, &pval);
				if (ret) {
					pr_err("%pOFn: couldn't read allowed modes index %d, ret=%d\n",
						np, i, ret);
					break;
				}
				mode = desc->of_map_mode(pval);
				if (mode == REGULATOR_MODE_INVALID)
					pr_err("%pOFn: invalid regulator-allowed-modes element %u\n",
						np, pval);
				else
					constraints->valid_modes_mask |= mode;
			}
			if (constraints->valid_modes_mask)
				constraints->valid_ops_mask
					|= REGULATOR_CHANGE_MODE;
		} else {
			pr_warn("%pOFn: mode mapping not defined\n", np);
		}
	}

	if (!of_property_read_u32(np, "regulator-system-load", &pval))
		constraints->system_load = pval;

	if (n_phandles) {
		constraints->max_spread = devm_kzalloc(dev,
				sizeof(*constraints->max_spread) * n_phandles,
				GFP_KERNEL);

		if (!constraints->max_spread)
			return -ENOMEM;

		of_property_read_u32_array(np, "regulator-coupled-max-spread",
					   constraints->max_spread, n_phandles);
	}

	if (!of_property_read_u32(np, "regulator-max-step-microvolt",
				  &pval))
		constraints->max_uV_step = pval;

	constraints->over_current_protection = of_property_read_bool(np,
					"regulator-over-current-protection");

	for (i = 0; i < ARRAY_SIZE(regulator_states); i++) {
		switch (i) {
		case PM_SUSPEND_MEM:
			suspend_state = &constraints->state_mem;
			break;
		case PM_SUSPEND_MAX:
			suspend_state = &constraints->state_disk;
			break;
		case PM_SUSPEND_STANDBY:
			suspend_state = &constraints->state_standby;
			break;
		case PM_SUSPEND_ON:
		case PM_SUSPEND_TO_IDLE:
		default:
			continue;
		}

		suspend_np = of_get_child_by_name(np, regulator_states[i]);
		if (!suspend_np || !suspend_state)
			continue;

		if (!of_property_read_u32(suspend_np, "regulator-mode",
					  &pval)) {
			if (desc && desc->of_map_mode) {
				mode = desc->of_map_mode(pval);
				if (mode == REGULATOR_MODE_INVALID)
					pr_err("%pOFn: invalid mode %u\n",
					       np, pval);
				else
					suspend_state->mode = mode;
			} else {
				pr_warn("%pOFn: mapping for mode %d not defined\n",
					np, pval);
			}
		}

		if (of_property_read_bool(suspend_np,
					"regulator-on-in-suspend"))
			suspend_state->enabled = ENABLE_IN_SUSPEND;
		else if (of_property_read_bool(suspend_np,
					"regulator-off-in-suspend"))
			suspend_state->enabled = DISABLE_IN_SUSPEND;

		if (!of_property_read_u32(suspend_np,
				"regulator-suspend-min-microvolt", &pval))
			suspend_state->min_uV = pval;

		if (!of_property_read_u32(suspend_np,
				"regulator-suspend-max-microvolt", &pval))
			suspend_state->max_uV = pval;

		if (!of_property_read_u32(suspend_np,
					"regulator-suspend-microvolt", &pval))
			suspend_state->uV = pval;
		else /* otherwise use min_uV as default suspend voltage */
			suspend_state->uV = suspend_state->min_uV;

		if (of_property_read_bool(suspend_np,
					"regulator-changeable-in-suspend"))
			suspend_state->changeable = true;

		if (i == PM_SUSPEND_MEM)
			constraints->initial_state = PM_SUSPEND_MEM;

		of_node_put(suspend_np);
		suspend_state = NULL;
		suspend_np = NULL;
	}

	return 0;
}

/**
 * of_get_regulator_init_data - extract regulator_init_data structure info
 * @dev: device requesting for regulator_init_data
 * @node: regulator device node
 * @desc: regulator description
 *
 * Populates regulator_init_data structure by extracting data from device
 * tree node, returns a pointer to the populated structure or NULL if memory
 * alloc fails.
 */
struct regulator_init_data *of_get_regulator_init_data(struct device *dev,
					  struct device_node *node,
					  const struct regulator_desc *desc)
{
	struct regulator_init_data *init_data;

	if (!node)
		return NULL;

	init_data = devm_kzalloc(dev, sizeof(*init_data), GFP_KERNEL);
	if (!init_data)
		return NULL; /* Out of memory? */

	if (of_get_regulation_constraints(dev, node, &init_data, desc))
		return NULL;

	return init_data;
}
EXPORT_SYMBOL_GPL(of_get_regulator_init_data);

struct devm_of_regulator_matches {
	struct of_regulator_match *matches;
	unsigned int num_matches;
};

static void devm_of_regulator_put_matches(struct device *dev, void *res)
{
	struct devm_of_regulator_matches *devm_matches = res;
	int i;

	for (i = 0; i < devm_matches->num_matches; i++)
		of_node_put(devm_matches->matches[i].of_node);
}

/**
 * of_regulator_match - extract multiple regulator init data from device tree.
 * @dev: device requesting the data
 * @node: parent device node of the regulators
 * @matches: match table for the regulators
 * @num_matches: number of entries in match table
 *
 * This function uses a match table specified by the regulator driver to
 * parse regulator init data from the device tree. @node is expected to
 * contain a set of child nodes, each providing the init data for one
 * regulator. The data parsed from a child node will be matched to a regulator
 * based on either the deprecated property regulator-compatible if present,
 * or otherwise the child node's name. Note that the match table is modified
 * in place and an additional of_node reference is taken for each matched
 * regulator.
 *
 * Returns the number of matches found or a negative error code on failure.
 */
int of_regulator_match(struct device *dev, struct device_node *node,
		       struct of_regulator_match *matches,
		       unsigned int num_matches)
{
	unsigned int count = 0;
	unsigned int i;
	const char *name;
	struct device_node *child;
	struct devm_of_regulator_matches *devm_matches;

	if (!dev || !node)
		return -EINVAL;

	devm_matches = devres_alloc(devm_of_regulator_put_matches,
				    sizeof(struct devm_of_regulator_matches),
				    GFP_KERNEL);
	if (!devm_matches)
		return -ENOMEM;

	devm_matches->matches = matches;
	devm_matches->num_matches = num_matches;

	devres_add(dev, devm_matches);

	for (i = 0; i < num_matches; i++) {
		struct of_regulator_match *match = &matches[i];
		match->init_data = NULL;
		match->of_node = NULL;
	}

	for_each_child_of_node(node, child) {
		name = of_get_property(child,
					"regulator-compatible", NULL);
		if (!name)
			name = child->name;
		for (i = 0; i < num_matches; i++) {
			struct of_regulator_match *match = &matches[i];
			if (match->of_node)
				continue;

			if (strcmp(match->name, name))
				continue;

			match->init_data =
				of_get_regulator_init_data(dev, child,
							   match->desc);
			if (!match->init_data) {
				dev_err(dev,
					"failed to parse DT for regulator %pOFn\n",
					child);
				of_node_put(child);
				return -EINVAL;
			}
			match->of_node = of_node_get(child);
			count++;
			break;
		}
	}

	return count;
}
EXPORT_SYMBOL_GPL(of_regulator_match);

static struct
device_node *regulator_of_get_init_node(struct device *dev,
					const struct regulator_desc *desc)
{
	struct device_node *search, *child;
	const char *name;

	if (!dev->of_node || !desc->of_match)
		return NULL;

	if (desc->regulators_node) {
		search = of_get_child_by_name(dev->of_node,
					      desc->regulators_node);
	} else {
		search = of_node_get(dev->of_node);

		if (!strcmp(desc->of_match, search->name))
			return search;
	}

	if (!search) {
		dev_dbg(dev, "Failed to find regulator container node '%s'\n",
			desc->regulators_node);
		return NULL;
	}

	for_each_available_child_of_node(search, child) {
		name = of_get_property(child, "regulator-compatible", NULL);
		if (!name)
			name = child->name;

		if (!strcmp(desc->of_match, name)) {
			of_node_put(search);
			return of_node_get(child);
		}
	}

	of_node_put(search);

	return NULL;
}

struct regulator_init_data *regulator_of_get_init_data(struct device *dev,
					    const struct regulator_desc *desc,
					    struct regulator_config *config,
					    struct device_node **node)
{
	struct device_node *child;
	struct regulator_init_data *init_data = NULL;

	child = regulator_of_get_init_node(dev, desc);
	if (!child)
		return NULL;

	init_data = of_get_regulator_init_data(dev, child, desc);
	if (!init_data) {
		dev_err(dev, "failed to parse DT for regulator %pOFn\n", child);
		goto error;
	}

	if (desc->of_parse_cb) {
		int ret;

		ret = desc->of_parse_cb(child, desc, config);
		if (ret) {
			if (ret == -EPROBE_DEFER) {
				of_node_put(child);
				return ERR_PTR(-EPROBE_DEFER);
			}
			dev_err(dev,
				"driver callback failed to parse DT for regulator %pOFn\n",
				child);
			goto error;
		}
	}

	*node = child;

	return init_data;

error:
	of_node_put(child);

	return NULL;
}

struct regulator_dev *of_find_regulator_by_node(struct device_node *np)
{
	struct device *dev;

	dev = class_find_device_by_of_node(&regulator_class, np);

	return dev ? dev_to_rdev(dev) : NULL;
}

/*
 * Returns number of regulators coupled with rdev.
 */
int of_get_n_coupled(struct regulator_dev *rdev)
{
	struct device_node *node = rdev->dev.of_node;
	int n_phandles;

	n_phandles = of_count_phandle_with_args(node,
						"regulator-coupled-with",
						NULL);

	return (n_phandles > 0) ? n_phandles : 0;
}

/* Looks for "to_find" device_node in src's "regulator-coupled-with" property */
static bool of_coupling_find_node(struct device_node *src,
				  struct device_node *to_find,
				  int *index)
{
	int n_phandles, i;
	bool found = false;

	n_phandles = of_count_phandle_with_args(src,
						"regulator-coupled-with",
						NULL);

	for (i = 0; i < n_phandles; i++) {
		struct device_node *tmp = of_parse_phandle(src,
					   "regulator-coupled-with", i);

		if (!tmp)
			break;

		/* found */
		if (tmp == to_find)
			found = true;

		of_node_put(tmp);

		if (found) {
			*index = i;
			break;
		}
	}

	return found;
}

/**
 * of_check_coupling_data - Parse rdev's coupling properties and check data
 *			    consistency
 * @rdev: pointer to regulator_dev whose data is checked
 *
 * Function checks if all the following conditions are met:
 * - rdev's max_spread is greater than 0
 * - all coupled regulators have the same max_spread
 * - all coupled regulators have the same number of regulator_dev phandles
 * - all regulators are linked to each other
 *
 * Returns true if all conditions are met.
 */
bool of_check_coupling_data(struct regulator_dev *rdev)
{
	struct device_node *node = rdev->dev.of_node;
	int n_phandles = of_get_n_coupled(rdev);
	struct device_node *c_node;
	int index;
	int i;
	bool ret = true;

	/* iterate over rdev's phandles */
	for (i = 0; i < n_phandles; i++) {
		int max_spread = rdev->constraints->max_spread[i];
		int c_max_spread, c_n_phandles;

		if (max_spread <= 0) {
			dev_err(&rdev->dev, "max_spread value invalid\n");
			return false;
		}

		c_node = of_parse_phandle(node,
					  "regulator-coupled-with", i);

		if (!c_node)
			ret = false;

		c_n_phandles = of_count_phandle_with_args(c_node,
							  "regulator-coupled-with",
							  NULL);

		if (c_n_phandles != n_phandles) {
			dev_err(&rdev->dev, "number of coupled reg phandles mismatch\n");
			ret = false;
			goto clean;
		}

		if (!of_coupling_find_node(c_node, node, &index)) {
			dev_err(&rdev->dev, "missing 2-way linking for coupled regulators\n");
			ret = false;
			goto clean;
		}

		if (of_property_read_u32_index(c_node, "regulator-coupled-max-spread",
					       index, &c_max_spread)) {
			ret = false;
			goto clean;
		}

		if (c_max_spread != max_spread) {
			dev_err(&rdev->dev,
				"coupled regulators max_spread mismatch\n");
			ret = false;
			goto clean;
		}

clean:
		of_node_put(c_node);
		if (!ret)
			break;
	}

	return ret;
}

/**
 * of_parse_coupled regulator - Get regulator_dev pointer from rdev's property
 * @rdev: Pointer to regulator_dev, whose DTS is used as a source to parse
 *	  "regulator-coupled-with" property
 * @index: Index in phandles array
 *
 * Returns the regulator_dev pointer parsed from DTS. If it has not been yet
 * registered, returns NULL
 */
struct regulator_dev *of_parse_coupled_regulator(struct regulator_dev *rdev,
						 int index)
{
	struct device_node *node = rdev->dev.of_node;
	struct device_node *c_node;
	struct regulator_dev *c_rdev;

	c_node = of_parse_phandle(node, "regulator-coupled-with", index);
	if (!c_node)
		return NULL;

	c_rdev = of_find_regulator_by_node(c_node);

	of_node_put(c_node);

	return c_rdev;
}