summaryrefslogtreecommitdiff
path: root/drivers/acpi/property.c
blob: 333f9146d19e1c02d6f0c1572f59847660963e27 (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
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
/*
 * ACPI device specific properties support.
 *
 * Copyright (C) 2014, Intel Corporation
 * All rights reserved.
 *
 * Authors: Mika Westerberg <mika.westerberg@linux.intel.com>
 *          Darren Hart <dvhart@linux.intel.com>
 *          Rafael J. Wysocki <rafael.j.wysocki@intel.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/acpi.h>
#include <linux/device.h>
#include <linux/export.h>

#include "internal.h"

/* ACPI _DSD device properties UUID: daffd814-6eba-4d8c-8a91-bc9bbf4aa301 */
static const u8 prp_uuid[16] = {
	0x14, 0xd8, 0xff, 0xda, 0xba, 0x6e, 0x8c, 0x4d,
	0x8a, 0x91, 0xbc, 0x9b, 0xbf, 0x4a, 0xa3, 0x01
};
/* ACPI _DSD data subnodes UUID: dbb8e3e6-5886-4ba6-8795-1319f52a966b */
static const u8 ads_uuid[16] = {
	0xe6, 0xe3, 0xb8, 0xdb, 0x86, 0x58, 0xa6, 0x4b,
	0x87, 0x95, 0x13, 0x19, 0xf5, 0x2a, 0x96, 0x6b
};

static bool acpi_enumerate_nondev_subnodes(acpi_handle scope,
					   const union acpi_object *desc,
					   struct acpi_device_data *data);
static bool acpi_extract_properties(const union acpi_object *desc,
				    struct acpi_device_data *data);

static bool acpi_nondev_subnode_ok(acpi_handle scope,
				   const union acpi_object *link,
				   struct list_head *list)
{
	struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
	struct acpi_data_node *dn;
	acpi_handle handle;
	acpi_status status;

	dn = kzalloc(sizeof(*dn), GFP_KERNEL);
	if (!dn)
		return false;

	dn->name = link->package.elements[0].string.pointer;
	dn->fwnode.type = FWNODE_ACPI_DATA;
	INIT_LIST_HEAD(&dn->data.subnodes);

	status = acpi_get_handle(scope, link->package.elements[1].string.pointer,
				 &handle);
	if (ACPI_FAILURE(status))
		goto fail;

	status = acpi_evaluate_object_typed(handle, NULL, NULL, &buf,
					    ACPI_TYPE_PACKAGE);
	if (ACPI_FAILURE(status))
		goto fail;

	if (acpi_extract_properties(buf.pointer, &dn->data))
		dn->handle = handle;

	if (acpi_enumerate_nondev_subnodes(scope, buf.pointer, &dn->data))
		dn->handle = handle;

	if (dn->handle) {
		dn->data.pointer = buf.pointer;
		list_add_tail(&dn->sibling, list);
		return true;
	}

	acpi_handle_debug(handle, "Invalid properties/subnodes data, skipping\n");

 fail:
	ACPI_FREE(buf.pointer);
	kfree(dn);
	return false;
}

static int acpi_add_nondev_subnodes(acpi_handle scope,
				    const union acpi_object *links,
				    struct list_head *list)
{
	bool ret = false;
	int i;

	for (i = 0; i < links->package.count; i++) {
		const union acpi_object *link;

		link = &links->package.elements[i];
		/* Only two elements allowed, both must be strings. */
		if (link->package.count == 2
		    && link->package.elements[0].type == ACPI_TYPE_STRING
		    && link->package.elements[1].type == ACPI_TYPE_STRING
		    && acpi_nondev_subnode_ok(scope, link, list))
			ret = true;
	}

	return ret;
}

static bool acpi_enumerate_nondev_subnodes(acpi_handle scope,
					   const union acpi_object *desc,
					   struct acpi_device_data *data)
{
	int i;

	/* Look for the ACPI data subnodes UUID. */
	for (i = 0; i < desc->package.count; i += 2) {
		const union acpi_object *uuid, *links;

		uuid = &desc->package.elements[i];
		links = &desc->package.elements[i + 1];

		/*
		 * The first element must be a UUID and the second one must be
		 * a package.
		 */
		if (uuid->type != ACPI_TYPE_BUFFER || uuid->buffer.length != 16
		    || links->type != ACPI_TYPE_PACKAGE)
			break;

		if (memcmp(uuid->buffer.pointer, ads_uuid, sizeof(ads_uuid)))
			continue;

		return acpi_add_nondev_subnodes(scope, links, &data->subnodes);
	}

	return false;
}

static bool acpi_property_value_ok(const union acpi_object *value)
{
	int j;

	/*
	 * The value must be an integer, a string, a reference, or a package
	 * whose every element must be an integer, a string, or a reference.
	 */
	switch (value->type) {
	case ACPI_TYPE_INTEGER:
	case ACPI_TYPE_STRING:
	case ACPI_TYPE_LOCAL_REFERENCE:
		return true;

	case ACPI_TYPE_PACKAGE:
		for (j = 0; j < value->package.count; j++)
			switch (value->package.elements[j].type) {
			case ACPI_TYPE_INTEGER:
			case ACPI_TYPE_STRING:
			case ACPI_TYPE_LOCAL_REFERENCE:
				continue;

			default:
				return false;
			}

		return true;
	}
	return false;
}

static bool acpi_properties_format_valid(const union acpi_object *properties)
{
	int i;

	for (i = 0; i < properties->package.count; i++) {
		const union acpi_object *property;

		property = &properties->package.elements[i];
		/*
		 * Only two elements allowed, the first one must be a string and
		 * the second one has to satisfy certain conditions.
		 */
		if (property->package.count != 2
		    || property->package.elements[0].type != ACPI_TYPE_STRING
		    || !acpi_property_value_ok(&property->package.elements[1]))
			return false;
	}
	return true;
}

static void acpi_init_of_compatible(struct acpi_device *adev)
{
	const union acpi_object *of_compatible;
	int ret;

	ret = acpi_dev_get_property_array(adev, "compatible", ACPI_TYPE_STRING,
					  &of_compatible);
	if (ret) {
		ret = acpi_dev_get_property(adev, "compatible",
					    ACPI_TYPE_STRING, &of_compatible);
		if (ret) {
			if (adev->parent
			    && adev->parent->flags.of_compatible_ok)
				goto out;

			return;
		}
	}
	adev->data.of_compatible = of_compatible;

 out:
	adev->flags.of_compatible_ok = 1;
}

static bool acpi_extract_properties(const union acpi_object *desc,
				    struct acpi_device_data *data)
{
	int i;

	if (desc->package.count % 2)
		return false;

	/* Look for the device properties UUID. */
	for (i = 0; i < desc->package.count; i += 2) {
		const union acpi_object *uuid, *properties;

		uuid = &desc->package.elements[i];
		properties = &desc->package.elements[i + 1];

		/*
		 * The first element must be a UUID and the second one must be
		 * a package.
		 */
		if (uuid->type != ACPI_TYPE_BUFFER || uuid->buffer.length != 16
		    || properties->type != ACPI_TYPE_PACKAGE)
			break;

		if (memcmp(uuid->buffer.pointer, prp_uuid, sizeof(prp_uuid)))
			continue;

		/*
		 * We found the matching UUID. Now validate the format of the
		 * package immediately following it.
		 */
		if (!acpi_properties_format_valid(properties))
			break;

		data->properties = properties;
		return true;
	}

	return false;
}

void acpi_init_properties(struct acpi_device *adev)
{
	struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
	struct acpi_hardware_id *hwid;
	acpi_status status;
	bool acpi_of = false;

	INIT_LIST_HEAD(&adev->data.subnodes);

	/*
	 * Check if ACPI_DT_NAMESPACE_HID is present and inthat case we fill in
	 * Device Tree compatible properties for this device.
	 */
	list_for_each_entry(hwid, &adev->pnp.ids, list) {
		if (!strcmp(hwid->id, ACPI_DT_NAMESPACE_HID)) {
			acpi_of = true;
			break;
		}
	}

	status = acpi_evaluate_object_typed(adev->handle, "_DSD", NULL, &buf,
					    ACPI_TYPE_PACKAGE);
	if (ACPI_FAILURE(status))
		goto out;

	if (acpi_extract_properties(buf.pointer, &adev->data)) {
		adev->data.pointer = buf.pointer;
		if (acpi_of)
			acpi_init_of_compatible(adev);
	}
	if (acpi_enumerate_nondev_subnodes(adev->handle, buf.pointer, &adev->data))
		adev->data.pointer = buf.pointer;

	if (!adev->data.pointer) {
		acpi_handle_debug(adev->handle, "Invalid _DSD data, skipping\n");
		ACPI_FREE(buf.pointer);
	}

 out:
	if (acpi_of && !adev->flags.of_compatible_ok)
		acpi_handle_info(adev->handle,
			 ACPI_DT_NAMESPACE_HID " requires 'compatible' property\n");
}

static void acpi_destroy_nondev_subnodes(struct list_head *list)
{
	struct acpi_data_node *dn, *next;

	if (list_empty(list))
		return;

	list_for_each_entry_safe_reverse(dn, next, list, sibling) {
		acpi_destroy_nondev_subnodes(&dn->data.subnodes);
		wait_for_completion(&dn->kobj_done);
		list_del(&dn->sibling);
		ACPI_FREE((void *)dn->data.pointer);
		kfree(dn);
	}
}

void acpi_free_properties(struct acpi_device *adev)
{
	acpi_destroy_nondev_subnodes(&adev->data.subnodes);
	ACPI_FREE((void *)adev->data.pointer);
	adev->data.of_compatible = NULL;
	adev->data.pointer = NULL;
	adev->data.properties = NULL;
}

/**
 * acpi_dev_get_property - return an ACPI property with given name
 * @adev: ACPI device to get property
 * @name: Name of the property
 * @type: Expected property type
 * @obj: Location to store the property value (if not %NULL)
 *
 * Look up a property with @name and store a pointer to the resulting ACPI
 * object at the location pointed to by @obj if found.
 *
 * Callers must not attempt to free the returned objects.  These objects will be
 * freed by the ACPI core automatically during the removal of @adev.
 *
 * Return: %0 if property with @name has been found (success),
 *         %-EINVAL if the arguments are invalid,
 *         %-ENODATA if the property doesn't exist,
 *         %-EPROTO if the property value type doesn't match @type.
 */
int acpi_dev_get_property(struct acpi_device *adev, const char *name,
			  acpi_object_type type, const union acpi_object **obj)
{
	const union acpi_object *properties;
	int i;

	if (!adev || !name)
		return -EINVAL;

	if (!adev->data.pointer || !adev->data.properties)
		return -ENODATA;

	properties = adev->data.properties;
	for (i = 0; i < properties->package.count; i++) {
		const union acpi_object *propname, *propvalue;
		const union acpi_object *property;

		property = &properties->package.elements[i];

		propname = &property->package.elements[0];
		propvalue = &property->package.elements[1];

		if (!strcmp(name, propname->string.pointer)) {
			if (type != ACPI_TYPE_ANY && propvalue->type != type)
				return -EPROTO;
			else if (obj)
				*obj = propvalue;

			return 0;
		}
	}
	return -ENODATA;
}
EXPORT_SYMBOL_GPL(acpi_dev_get_property);

/**
 * acpi_dev_get_property_array - return an ACPI array property with given name
 * @adev: ACPI device to get property
 * @name: Name of the property
 * @type: Expected type of array elements
 * @obj: Location to store a pointer to the property value (if not NULL)
 *
 * Look up an array property with @name and store a pointer to the resulting
 * ACPI object at the location pointed to by @obj if found.
 *
 * Callers must not attempt to free the returned objects.  Those objects will be
 * freed by the ACPI core automatically during the removal of @adev.
 *
 * Return: %0 if array property (package) with @name has been found (success),
 *         %-EINVAL if the arguments are invalid,
 *         %-ENODATA if the property doesn't exist,
 *         %-EPROTO if the property is not a package or the type of its elements
 *           doesn't match @type.
 */
int acpi_dev_get_property_array(struct acpi_device *adev, const char *name,
				acpi_object_type type,
				const union acpi_object **obj)
{
	const union acpi_object *prop;
	int ret, i;

	ret = acpi_dev_get_property(adev, name, ACPI_TYPE_PACKAGE, &prop);
	if (ret)
		return ret;

	if (type != ACPI_TYPE_ANY) {
		/* Check that all elements are of correct type. */
		for (i = 0; i < prop->package.count; i++)
			if (prop->package.elements[i].type != type)
				return -EPROTO;
	}
	if (obj)
		*obj = prop;

	return 0;
}
EXPORT_SYMBOL_GPL(acpi_dev_get_property_array);

/**
 * acpi_dev_get_property_reference - returns handle to the referenced object
 * @adev: ACPI device to get property
 * @name: Name of the property
 * @index: Index of the reference to return
 * @args: Location to store the returned reference with optional arguments
 *
 * Find property with @name, verifify that it is a package containing at least
 * one object reference and if so, store the ACPI device object pointer to the
 * target object in @args->adev.  If the reference includes arguments, store
 * them in the @args->args[] array.
 *
 * If there's more than one reference in the property value package, @index is
 * used to select the one to return.
 *
 * Return: %0 on success, negative error code on failure.
 */
int acpi_dev_get_property_reference(struct acpi_device *adev,
				    const char *name, size_t index,
				    struct acpi_reference_args *args)
{
	const union acpi_object *element, *end;
	const union acpi_object *obj;
	struct acpi_device *device;
	int ret, idx = 0;

	ret = acpi_dev_get_property(adev, name, ACPI_TYPE_ANY, &obj);
	if (ret)
		return ret;

	/*
	 * The simplest case is when the value is a single reference.  Just
	 * return that reference then.
	 */
	if (obj->type == ACPI_TYPE_LOCAL_REFERENCE) {
		if (index)
			return -EINVAL;

		ret = acpi_bus_get_device(obj->reference.handle, &device);
		if (ret)
			return ret;

		args->adev = device;
		args->nargs = 0;
		return 0;
	}

	/*
	 * If it is not a single reference, then it is a package of
	 * references followed by number of ints as follows:
	 *
	 *  Package () { REF, INT, REF, INT, INT }
	 *
	 * The index argument is then used to determine which reference
	 * the caller wants (along with the arguments).
	 */
	if (obj->type != ACPI_TYPE_PACKAGE || index >= obj->package.count)
		return -EPROTO;

	element = obj->package.elements;
	end = element + obj->package.count;

	while (element < end) {
		u32 nargs, i;

		if (element->type != ACPI_TYPE_LOCAL_REFERENCE)
			return -EPROTO;

		ret = acpi_bus_get_device(element->reference.handle, &device);
		if (ret)
			return -ENODEV;

		element++;
		nargs = 0;

		/* assume following integer elements are all args */
		for (i = 0; element + i < end; i++) {
			int type = element[i].type;

			if (type == ACPI_TYPE_INTEGER)
				nargs++;
			else if (type == ACPI_TYPE_LOCAL_REFERENCE)
				break;
			else
				return -EPROTO;
		}

		if (idx++ == index) {
			args->adev = device;
			args->nargs = nargs;
			for (i = 0; i < nargs; i++)
				args->args[i] = element[i].integer.value;

			return 0;
		}

		element += nargs;
	}

	return -EPROTO;
}
EXPORT_SYMBOL_GPL(acpi_dev_get_property_reference);

int acpi_dev_prop_get(struct acpi_device *adev, const char *propname,
		      void **valptr)
{
	return acpi_dev_get_property(adev, propname, ACPI_TYPE_ANY,
				     (const union acpi_object **)valptr);
}

int acpi_dev_prop_read_single(struct acpi_device *adev, const char *propname,
			      enum dev_prop_type proptype, void *val)
{
	const union acpi_object *obj;
	int ret;

	if (!val)
		return -EINVAL;

	if (proptype >= DEV_PROP_U8 && proptype <= DEV_PROP_U64) {
		ret = acpi_dev_get_property(adev, propname, ACPI_TYPE_INTEGER, &obj);
		if (ret)
			return ret;

		switch (proptype) {
		case DEV_PROP_U8:
			if (obj->integer.value > U8_MAX)
				return -EOVERFLOW;
			*(u8 *)val = obj->integer.value;
			break;
		case DEV_PROP_U16:
			if (obj->integer.value > U16_MAX)
				return -EOVERFLOW;
			*(u16 *)val = obj->integer.value;
			break;
		case DEV_PROP_U32:
			if (obj->integer.value > U32_MAX)
				return -EOVERFLOW;
			*(u32 *)val = obj->integer.value;
			break;
		default:
			*(u64 *)val = obj->integer.value;
			break;
		}
	} else if (proptype == DEV_PROP_STRING) {
		ret = acpi_dev_get_property(adev, propname, ACPI_TYPE_STRING, &obj);
		if (ret)
			return ret;

		*(char **)val = obj->string.pointer;
	} else {
		ret = -EINVAL;
	}
	return ret;
}

static int acpi_copy_property_array_u8(const union acpi_object *items, u8 *val,
				       size_t nval)
{
	int i;

	for (i = 0; i < nval; i++) {
		if (items[i].type != ACPI_TYPE_INTEGER)
			return -EPROTO;
		if (items[i].integer.value > U8_MAX)
			return -EOVERFLOW;

		val[i] = items[i].integer.value;
	}
	return 0;
}

static int acpi_copy_property_array_u16(const union acpi_object *items,
					u16 *val, size_t nval)
{
	int i;

	for (i = 0; i < nval; i++) {
		if (items[i].type != ACPI_TYPE_INTEGER)
			return -EPROTO;
		if (items[i].integer.value > U16_MAX)
			return -EOVERFLOW;

		val[i] = items[i].integer.value;
	}
	return 0;
}

static int acpi_copy_property_array_u32(const union acpi_object *items,
					u32 *val, size_t nval)
{
	int i;

	for (i = 0; i < nval; i++) {
		if (items[i].type != ACPI_TYPE_INTEGER)
			return -EPROTO;
		if (items[i].integer.value > U32_MAX)
			return -EOVERFLOW;

		val[i] = items[i].integer.value;
	}
	return 0;
}

static int acpi_copy_property_array_u64(const union acpi_object *items,
					u64 *val, size_t nval)
{
	int i;

	for (i = 0; i < nval; i++) {
		if (items[i].type != ACPI_TYPE_INTEGER)
			return -EPROTO;

		val[i] = items[i].integer.value;
	}
	return 0;
}

static int acpi_copy_property_array_string(const union acpi_object *items,
					   char **val, size_t nval)
{
	int i;

	for (i = 0; i < nval; i++) {
		if (items[i].type != ACPI_TYPE_STRING)
			return -EPROTO;

		val[i] = items[i].string.pointer;
	}
	return 0;
}

int acpi_dev_prop_read(struct acpi_device *adev, const char *propname,
		       enum dev_prop_type proptype, void *val, size_t nval)
{
	const union acpi_object *obj;
	const union acpi_object *items;
	int ret;

	if (val && nval == 1) {
		ret = acpi_dev_prop_read_single(adev, propname, proptype, val);
		if (!ret)
			return ret;
	}

	ret = acpi_dev_get_property_array(adev, propname, ACPI_TYPE_ANY, &obj);
	if (ret)
		return ret;

	if (!val)
		return obj->package.count;

	if (nval > obj->package.count)
		return -EOVERFLOW;
	else if (nval <= 0)
		return -EINVAL;

	items = obj->package.elements;

	switch (proptype) {
	case DEV_PROP_U8:
		ret = acpi_copy_property_array_u8(items, (u8 *)val, nval);
		break;
	case DEV_PROP_U16:
		ret = acpi_copy_property_array_u16(items, (u16 *)val, nval);
		break;
	case DEV_PROP_U32:
		ret = acpi_copy_property_array_u32(items, (u32 *)val, nval);
		break;
	case DEV_PROP_U64:
		ret = acpi_copy_property_array_u64(items, (u64 *)val, nval);
		break;
	case DEV_PROP_STRING:
		ret = acpi_copy_property_array_string(items, (char **)val, nval);
		break;
	default:
		ret = -EINVAL;
		break;
	}
	return ret;
}