summaryrefslogtreecommitdiffstats
path: root/drivers/acpi/property.c
blob: 9d460a859be0770d251f8e92589551b01da5aa4b (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
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
/*
 * 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"

static int acpi_data_get_property_array(const struct acpi_device_data *data,
					const char *name,
					acpi_object_type type,
					const union acpi_object **obj);

/*
 * The GUIDs here are made equivalent to each other in order to avoid extra
 * complexity in the properties handling code, with the caveat that the
 * kernel will accept certain combinations of GUID and properties that are
 * not defined without a warning. For instance if any of the properties
 * from different GUID appear in a property list of another, it will be
 * accepted by the kernel. Firmware validation tools should catch these.
 */
static const guid_t prp_guids[] = {
	/* ACPI _DSD device properties GUID: daffd814-6eba-4d8c-8a91-bc9bbf4aa301 */
	GUID_INIT(0xdaffd814, 0x6eba, 0x4d8c,
		  0x8a, 0x91, 0xbc, 0x9b, 0xbf, 0x4a, 0xa3, 0x01),
	/* Hotplug in D3 GUID: 6211e2c0-58a3-4af3-90e1-927a4e0c55a4 */
	GUID_INIT(0x6211e2c0, 0x58a3, 0x4af3,
		  0x90, 0xe1, 0x92, 0x7a, 0x4e, 0x0c, 0x55, 0xa4),
	/* External facing port GUID: efcc06cc-73ac-4bc3-bff0-76143807c389 */
	GUID_INIT(0xefcc06cc, 0x73ac, 0x4bc3,
		  0xbf, 0xf0, 0x76, 0x14, 0x38, 0x07, 0xc3, 0x89),
};

/* ACPI _DSD data subnodes GUID: dbb8e3e6-5886-4ba6-8795-1319f52a966b */
static const guid_t ads_guid =
	GUID_INIT(0xdbb8e3e6, 0x5886, 0x4ba6,
		  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,
					   struct fwnode_handle *parent);
static bool acpi_extract_properties(const union acpi_object *desc,
				    struct acpi_device_data *data);

static bool acpi_nondev_subnode_extract(const union acpi_object *desc,
					acpi_handle handle,
					const union acpi_object *link,
					struct list_head *list,
					struct fwnode_handle *parent)
{
	struct acpi_data_node *dn;
	bool result;

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

	dn->name = link->package.elements[0].string.pointer;
	dn->fwnode.ops = &acpi_data_fwnode_ops;
	dn->parent = parent;
	INIT_LIST_HEAD(&dn->data.properties);
	INIT_LIST_HEAD(&dn->data.subnodes);

	result = acpi_extract_properties(desc, &dn->data);

	if (handle) {
		acpi_handle scope;
		acpi_status status;

		/*
		 * The scope for the subnode object lookup is the one of the
		 * namespace node (device) containing the object that has
		 * returned the package.  That is, it's the scope of that
		 * object's parent.
		 */
		status = acpi_get_parent(handle, &scope);
		if (ACPI_SUCCESS(status)
		    && acpi_enumerate_nondev_subnodes(scope, desc, &dn->data,
						      &dn->fwnode))
			result = true;
	} else if (acpi_enumerate_nondev_subnodes(NULL, desc, &dn->data,
						  &dn->fwnode)) {
		result = true;
	}

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

	kfree(dn);
	acpi_handle_debug(handle, "Invalid properties/subnodes data, skipping\n");
	return false;
}

static bool acpi_nondev_subnode_data_ok(acpi_handle handle,
					const union acpi_object *link,
					struct list_head *list,
					struct fwnode_handle *parent)
{
	struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
	acpi_status status;

	status = acpi_evaluate_object_typed(handle, NULL, NULL, &buf,
					    ACPI_TYPE_PACKAGE);
	if (ACPI_FAILURE(status))
		return false;

	if (acpi_nondev_subnode_extract(buf.pointer, handle, link, list,
					parent))
		return true;

	ACPI_FREE(buf.pointer);
	return false;
}

static bool acpi_nondev_subnode_ok(acpi_handle scope,
				   const union acpi_object *link,
				   struct list_head *list,
				   struct fwnode_handle *parent)
{
	acpi_handle handle;
	acpi_status status;

	if (!scope)
		return false;

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

	return acpi_nondev_subnode_data_ok(handle, link, list, parent);
}

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

	for (i = 0; i < links->package.count; i++) {
		const union acpi_object *link, *desc;
		acpi_handle handle;
		bool result;

		link = &links->package.elements[i];
		/* Only two elements allowed. */
		if (link->package.count != 2)
			continue;

		/* The first one must be a string. */
		if (link->package.elements[0].type != ACPI_TYPE_STRING)
			continue;

		/* The second one may be a string, a reference or a package. */
		switch (link->package.elements[1].type) {
		case ACPI_TYPE_STRING:
			result = acpi_nondev_subnode_ok(scope, link, list,
							 parent);
			break;
		case ACPI_TYPE_LOCAL_REFERENCE:
			handle = link->package.elements[1].reference.handle;
			result = acpi_nondev_subnode_data_ok(handle, link, list,
							     parent);
			break;
		case ACPI_TYPE_PACKAGE:
			desc = &link->package.elements[1];
			result = acpi_nondev_subnode_extract(desc, NULL, link,
							     list, parent);
			break;
		default:
			result = false;
			break;
		}
		ret = ret || result;
	}

	return ret;
}

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

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

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

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

		if (!guid_equal((guid_t *)guid->buffer.pointer, &ads_guid))
			continue;

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

	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_data_get_property_array(&adev->data, "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_is_property_guid(const guid_t *guid)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(prp_guids); i++) {
		if (guid_equal(guid, &prp_guids[i]))
			return true;
	}

	return false;
}

struct acpi_device_properties *
acpi_data_add_props(struct acpi_device_data *data, const guid_t *guid,
		    const union acpi_object *properties)
{
	struct acpi_device_properties *props;

	props = kzalloc(sizeof(*props), GFP_KERNEL);
	if (props) {
		INIT_LIST_HEAD(&props->list);
		props->guid = guid;
		props->properties = properties;
		list_add_tail(&props->list, &data->properties);
	}

	return props;
}

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 GUID. */
	for (i = 0; i < desc->package.count; i += 2) {
		const union acpi_object *guid, *properties;

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

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

		if (!acpi_is_property_guid((guid_t *)guid->buffer.pointer))
			continue;

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

		acpi_data_add_props(data, (const guid_t *)guid->buffer.pointer,
				    properties);
	}

	return !list_empty(&data->properties);
}

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.properties);
	INIT_LIST_HEAD(&adev->data.subnodes);

	if (!adev->handle)
		return;

	/*
	 * 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, acpi_fwnode_handle(adev)))
		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");

	if (!adev->data.pointer)
		acpi_extract_apple_properties(adev);
}

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)
{
	struct acpi_device_properties *props, *tmp;

	acpi_destroy_nondev_subnodes(&adev->data.subnodes);
	ACPI_FREE((void *)adev->data.pointer);
	adev->data.of_compatible = NULL;
	adev->data.pointer = NULL;
	list_for_each_entry_safe(props, tmp, &adev->data.properties, list) {
		list_del(&props->list);
		kfree(props);
	}
}

/**
 * acpi_data_get_property - return an ACPI property with given name
 * @data: ACPI device deta object to get the property from
 * @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 @data.
 *
 * Return: %0 if property with @name has been found (success),
 *         %-EINVAL if the arguments are invalid,
 *         %-EINVAL if the property doesn't exist,
 *         %-EPROTO if the property value type doesn't match @type.
 */
static int acpi_data_get_property(const struct acpi_device_data *data,
				  const char *name, acpi_object_type type,
				  const union acpi_object **obj)
{
	const struct acpi_device_properties *props;

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

	if (!data->pointer || list_empty(&data->properties))
		return -EINVAL;

	list_for_each_entry(props, &data->properties, list) {
		const union acpi_object *properties;
		unsigned int i;

		properties = props->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;
				if (obj)
					*obj = propvalue;

				return 0;
			}
		}
	}
	return -EINVAL;
}

/**
 * acpi_dev_get_property - return an ACPI property with given name.
 * @adev: ACPI device to get the property from.
 * @name: Name of the property.
 * @type: Expected property type.
 * @obj: Location to store the property value (if not %NULL).
 */
int acpi_dev_get_property(const struct acpi_device *adev, const char *name,
			  acpi_object_type type, const union acpi_object **obj)
{
	return adev ? acpi_data_get_property(&adev->data, name, type, obj) : -EINVAL;
}
EXPORT_SYMBOL_GPL(acpi_dev_get_property);

static const struct acpi_device_data *
acpi_device_data_of_node(const struct fwnode_handle *fwnode)
{
	if (is_acpi_device_node(fwnode)) {
		const struct acpi_device *adev = to_acpi_device_node(fwnode);
		return &adev->data;
	} else if (is_acpi_data_node(fwnode)) {
		const struct acpi_data_node *dn = to_acpi_data_node(fwnode);
		return &dn->data;
	}
	return NULL;
}

/**
 * acpi_node_prop_get - return an ACPI property with given name.
 * @fwnode: Firmware node to get the property from.
 * @propname: Name of the property.
 * @valptr: Location to store a pointer to the property value (if not %NULL).
 */
int acpi_node_prop_get(const struct fwnode_handle *fwnode,
		       const char *propname, void **valptr)
{
	return acpi_data_get_property(acpi_device_data_of_node(fwnode),
				      propname, ACPI_TYPE_ANY,
				      (const union acpi_object **)valptr);
}

/**
 * acpi_data_get_property_array - return an ACPI array property with given name
 * @adev: ACPI data object to get the property from
 * @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 @data.
 *
 * Return: %0 if array property (package) with @name has been found (success),
 *         %-EINVAL if the arguments are invalid,
 *         %-EINVAL if the property doesn't exist,
 *         %-EPROTO if the property is not a package or the type of its elements
 *           doesn't match @type.
 */
static int acpi_data_get_property_array(const struct acpi_device_data *data,
					const char *name,
					acpi_object_type type,
					const union acpi_object **obj)
{
	const union acpi_object *prop;
	int ret, i;

	ret = acpi_data_get_property(data, 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;
}

static struct fwnode_handle *
acpi_fwnode_get_named_child_node(const struct fwnode_handle *fwnode,
				 const char *childname)
{
	struct fwnode_handle *child;

	/*
	 * Find first matching named child node of this fwnode.
	 * For ACPI this will be a data only sub-node.
	 */
	fwnode_for_each_child_node(fwnode, child)
		if (acpi_data_node_match(child, childname))
			return child;

	return NULL;
}

/**
 * __acpi_node_get_property_reference - returns handle to the referenced object
 * @fwnode: Firmware node to get the property from
 * @propname: Name of the property
 * @index: Index of the reference to return
 * @num_args: Maximum number of arguments after each reference
 * @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.
 *
 * It is possible to leave holes in the property value set like in the
 * example below:
 *
 * Package () {
 *     "cs-gpios",
 *     Package () {
 *        ^GPIO, 19, 0, 0,
 *        ^GPIO, 20, 0, 0,
 *        0,
 *        ^GPIO, 21, 0, 0,
 *     }
 * }
 *
 * Calling this function with index %2 or index %3 return %-ENOENT. If the
 * property does not contain any more values %-ENOENT is returned. The NULL
 * entry must be single integer and preferably contain value %0.
 *
 * Return: %0 on success, negative error code on failure.
 */
int __acpi_node_get_property_reference(const struct fwnode_handle *fwnode,
	const char *propname, size_t index, size_t num_args,
	struct fwnode_reference_args *args)
{
	const union acpi_object *element, *end;
	const union acpi_object *obj;
	const struct acpi_device_data *data;
	struct acpi_device *device;
	int ret, idx = 0;

	data = acpi_device_data_of_node(fwnode);
	if (!data)
		return -ENOENT;

	ret = acpi_data_get_property(data, propname, ACPI_TYPE_ANY, &obj);
	if (ret)
		return ret == -EINVAL ? -ENOENT : -EINVAL;

	/*
	 * 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 == -ENODEV ? -EINVAL : ret;

		args->fwnode = acpi_fwnode_handle(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)
		return -EINVAL;
	if (index >= obj->package.count)
		return -ENOENT;

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

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

		if (element->type == ACPI_TYPE_LOCAL_REFERENCE) {
			struct fwnode_handle *ref_fwnode;

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

			nargs = 0;
			element++;

			/*
			 * Find the referred data extension node under the
			 * referred device node.
			 */
			for (ref_fwnode = acpi_fwnode_handle(device);
			     element < end && element->type == ACPI_TYPE_STRING;
			     element++) {
				ref_fwnode = acpi_fwnode_get_named_child_node(
					ref_fwnode, element->string.pointer);
				if (!ref_fwnode)
					return -EINVAL;
			}

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

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

			if (nargs > NR_FWNODE_REFERENCE_ARGS)
				return -EINVAL;

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

				return 0;
			}

			element += nargs;
		} else if (element->type == ACPI_TYPE_INTEGER) {
			if (idx == index)
				return -ENOENT;
			element++;
		} else {
			return -EINVAL;
		}

		idx++;
	}

	return -ENOENT;
}
EXPORT_SYMBOL_GPL(__acpi_node_get_property_reference);

static int acpi_data_prop_read_single(const struct acpi_device_data *data,
				      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_data_get_property(data, 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_data_get_property(data, propname, ACPI_TYPE_STRING, &obj);
		if (ret)
			return ret;

		*(char **)val = obj->string.pointer;

		return 1;
	} else {
		ret = -EINVAL;
	}
	return ret;
}

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

	if (!adev)
		return -EINVAL;

	ret = acpi_data_prop_read_single(&adev->data, propname, proptype, val);
	if (ret < 0 || proptype != ACPI_TYPE_STRING)
		return ret;
	return 0;
}

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 nval;
}

static int acpi_data_prop_read(const struct acpi_device_data *data,
			       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_data_prop_read_single(data, propname, proptype, val);
		if (ret >= 0)
			return ret;
	}

	ret = acpi_data_get_property_array(data, propname, ACPI_TYPE_ANY, &obj);
	if (ret)
		return ret;

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

	if (proptype != DEV_PROP_STRING && 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,
			min_t(u32, nval, obj->package.count));
		break;
	default:
		ret = -EINVAL;
		break;
	}
	return ret;
}

int acpi_dev_prop_read(const struct acpi_device *adev, const char *propname,
		       enum dev_prop_type proptype, void *val, size_t nval)
{
	return adev ? acpi_data_prop_read(&adev->data, propname, proptype, val, nval) : -EINVAL;
}

/**
 * acpi_node_prop_read - retrieve the value of an ACPI property with given name.
 * @fwnode: Firmware node to get the property from.
 * @propname: Name of the property.
 * @proptype: Expected property type.
 * @val: Location to store the property value (if not %NULL).
 * @nval: Size of the array pointed to by @val.
 *
 * If @val is %NULL, return the number of array elements comprising the value
 * of the property.  Otherwise, read at most @nval values to the array at the
 * location pointed to by @val.
 */
int acpi_node_prop_read(const struct fwnode_handle *fwnode,
			const char *propname, enum dev_prop_type proptype,
			void *val, size_t nval)
{
	return acpi_data_prop_read(acpi_device_data_of_node(fwnode),
				   propname, proptype, val, nval);
}

/**
 * acpi_get_next_subnode - Return the next child node handle for a fwnode
 * @fwnode: Firmware node to find the next child node for.
 * @child: Handle to one of the device's child nodes or a null handle.
 */
struct fwnode_handle *acpi_get_next_subnode(const struct fwnode_handle *fwnode,
					    struct fwnode_handle *child)
{
	const struct acpi_device *adev = to_acpi_device_node(fwnode);
	const struct list_head *head;
	struct list_head *next;

	if (!child || is_acpi_device_node(child)) {
		struct acpi_device *child_adev;

		if (adev)
			head = &adev->children;
		else
			goto nondev;

		if (list_empty(head))
			goto nondev;

		if (child) {
			adev = to_acpi_device_node(child);
			next = adev->node.next;
			if (next == head) {
				child = NULL;
				goto nondev;
			}
			child_adev = list_entry(next, struct acpi_device, node);
		} else {
			child_adev = list_first_entry(head, struct acpi_device,
						      node);
		}
		return acpi_fwnode_handle(child_adev);
	}

 nondev:
	if (!child || is_acpi_data_node(child)) {
		const struct acpi_data_node *data = to_acpi_data_node(fwnode);
		struct acpi_data_node *dn;

		/*
		 * We can have a combination of device and data nodes, e.g. with
		 * hierarchical _DSD properties. Make sure the adev pointer is
		 * restored before going through data nodes, otherwise we will
		 * be looking for data_nodes below the last device found instead
		 * of the common fwnode shared by device_nodes and data_nodes.
		 */
		adev = to_acpi_device_node(fwnode);
		if (adev)
			head = &adev->data.subnodes;
		else if (data)
			head = &data->data.subnodes;
		else
			return NULL;

		if (list_empty(head))
			return NULL;

		if (child) {
			dn = to_acpi_data_node(child);
			next = dn->sibling.next;
			if (next == head)
				return NULL;

			dn = list_entry(next, struct acpi_data_node, sibling);
		} else {
			dn = list_first_entry(head, struct acpi_data_node, sibling);
		}
		return &dn->fwnode;
	}
	return NULL;
}

/**
 * acpi_node_get_parent - Return parent fwnode of this fwnode
 * @fwnode: Firmware node whose parent to get
 *
 * Returns parent node of an ACPI device or data firmware node or %NULL if
 * not available.
 */
struct fwnode_handle *acpi_node_get_parent(const struct fwnode_handle *fwnode)
{
	if (is_acpi_data_node(fwnode)) {
		/* All data nodes have parent pointer so just return that */
		return to_acpi_data_node(fwnode)->parent;
	} else if (is_acpi_device_node(fwnode)) {
		acpi_handle handle, parent_handle;

		handle = to_acpi_device_node(fwnode)->handle;
		if (ACPI_SUCCESS(acpi_get_parent(handle, &parent_handle))) {
			struct acpi_device *adev;

			if (!acpi_bus_get_device(parent_handle, &adev))
				return acpi_fwnode_handle(adev);
		}
	}

	return NULL;
}

/*
 * Return true if the node is an ACPI graph node. Called on either ports
 * or endpoints.
 */
static bool is_acpi_graph_node(struct fwnode_handle *fwnode,
			       const char *str)
{
	unsigned int len = strlen(str);
	const char *name;

	if (!len || !is_acpi_data_node(fwnode))
		return false;

	name = to_acpi_data_node(fwnode)->name;

	return (fwnode_property_present(fwnode, "reg") &&
		!strncmp(name, str, len) && name[len] == '@') ||
		fwnode_property_present(fwnode, str);
}

/**
 * acpi_graph_get_next_endpoint - Get next endpoint ACPI firmware node
 * @fwnode: Pointer to the parent firmware node
 * @prev: Previous endpoint node or %NULL to get the first
 *
 * Looks up next endpoint ACPI firmware node below a given @fwnode. Returns
 * %NULL if there is no next endpoint or in case of error. In case of success
 * the next endpoint is returned.
 */
static struct fwnode_handle *acpi_graph_get_next_endpoint(
	const struct fwnode_handle *fwnode, struct fwnode_handle *prev)
{
	struct fwnode_handle *port = NULL;
	struct fwnode_handle *endpoint;

	if (!prev) {
		do {
			port = fwnode_get_next_child_node(fwnode, port);
			/*
			 * The names of the port nodes begin with "port@"
			 * followed by the number of the port node and they also
			 * have a "reg" property that also has the number of the
			 * port node. For compatibility reasons a node is also
			 * recognised as a port node from the "port" property.
			 */
			if (is_acpi_graph_node(port, "port"))
				break;
		} while (port);
	} else {
		port = fwnode_get_parent(prev);
	}

	if (!port)
		return NULL;

	endpoint = fwnode_get_next_child_node(port, prev);
	while (!endpoint) {
		port = fwnode_get_next_child_node(fwnode, port);
		if (!port)
			break;
		if (is_acpi_graph_node(port, "port"))
			endpoint = fwnode_get_next_child_node(port, NULL);
	}

	/*
	 * The names of the endpoint nodes begin with "endpoint@" followed by
	 * the number of the endpoint node and they also have a "reg" property
	 * that also has the number of the endpoint node. For compatibility
	 * reasons a node is also recognised as an endpoint node from the
	 * "endpoint" property.
	 */
	if (!is_acpi_graph_node(endpoint, "endpoint"))
		return NULL;

	return endpoint;
}

/**
 * acpi_graph_get_child_prop_value - Return a child with a given property value
 * @fwnode: device fwnode
 * @prop_name: The name of the property to look for
 * @val: the desired property value
 *
 * Return the port node corresponding to a given port number. Returns
 * the child node on success, NULL otherwise.
 */
static struct fwnode_handle *acpi_graph_get_child_prop_value(
	const struct fwnode_handle *fwnode, const char *prop_name,
	unsigned int val)
{
	struct fwnode_handle *child;

	fwnode_for_each_child_node(fwnode, child) {
		u32 nr;

		if (fwnode_property_read_u32(child, prop_name, &nr))
			continue;

		if (val == nr)
			return child;
	}

	return NULL;
}


/**
 * acpi_graph_get_remote_enpoint - Parses and returns remote end of an endpoint
 * @fwnode: Endpoint firmware node pointing to a remote device
 * @endpoint: Firmware node of remote endpoint is filled here if not %NULL
 *
 * Returns the remote endpoint corresponding to @__fwnode. NULL on error.
 */
static struct fwnode_handle *
acpi_graph_get_remote_endpoint(const struct fwnode_handle *__fwnode)
{
	struct fwnode_handle *fwnode;
	unsigned int port_nr, endpoint_nr;
	struct fwnode_reference_args args;
	int ret;

	memset(&args, 0, sizeof(args));
	ret = acpi_node_get_property_reference(__fwnode, "remote-endpoint", 0,
					       &args);
	if (ret)
		return NULL;

	/* Direct endpoint reference? */
	if (!is_acpi_device_node(args.fwnode))
		return args.nargs ? NULL : args.fwnode;

	/*
	 * Always require two arguments with the reference: port and
	 * endpoint indices.
	 */
	if (args.nargs != 2)
		return NULL;

	fwnode = args.fwnode;
	port_nr = args.args[0];
	endpoint_nr = args.args[1];

	fwnode = acpi_graph_get_child_prop_value(fwnode, "port", port_nr);

	return acpi_graph_get_child_prop_value(fwnode, "endpoint", endpoint_nr);
}

static bool acpi_fwnode_device_is_available(const struct fwnode_handle *fwnode)
{
	if (!is_acpi_device_node(fwnode))
		return false;

	return acpi_device_is_present(to_acpi_device_node(fwnode));
}

static bool acpi_fwnode_property_present(const struct fwnode_handle *fwnode,
					 const char *propname)
{
	return !acpi_node_prop_get(fwnode, propname, NULL);
}

static int
acpi_fwnode_property_read_int_array(const struct fwnode_handle *fwnode,
				    const char *propname,
				    unsigned int elem_size, void *val,
				    size_t nval)
{
	enum dev_prop_type type;

	switch (elem_size) {
	case sizeof(u8):
		type = DEV_PROP_U8;
		break;
	case sizeof(u16):
		type = DEV_PROP_U16;
		break;
	case sizeof(u32):
		type = DEV_PROP_U32;
		break;
	case sizeof(u64):
		type = DEV_PROP_U64;
		break;
	default:
		return -ENXIO;
	}

	return acpi_node_prop_read(fwnode, propname, type, val, nval);
}

static int
acpi_fwnode_property_read_string_array(const struct fwnode_handle *fwnode,
				       const char *propname, const char **val,
				       size_t nval)
{
	return acpi_node_prop_read(fwnode, propname, DEV_PROP_STRING,
				   val, nval);
}

static int
acpi_fwnode_get_reference_args(const struct fwnode_handle *fwnode,
			       const char *prop, const char *nargs_prop,
			       unsigned int args_count, unsigned int index,
			       struct fwnode_reference_args *args)
{
	return __acpi_node_get_property_reference(fwnode, prop, index,
						  args_count, args);
}

static struct fwnode_handle *
acpi_fwnode_get_parent(struct fwnode_handle *fwnode)
{
	return acpi_node_get_parent(fwnode);
}

static int acpi_fwnode_graph_parse_endpoint(const struct fwnode_handle *fwnode,
					    struct fwnode_endpoint *endpoint)
{
	struct fwnode_handle *port_fwnode = fwnode_get_parent(fwnode);

	endpoint->local_fwnode = fwnode;

	if (fwnode_property_read_u32(port_fwnode, "reg", &endpoint->port))
		fwnode_property_read_u32(port_fwnode, "port", &endpoint->port);
	if (fwnode_property_read_u32(fwnode, "reg", &endpoint->id))
		fwnode_property_read_u32(fwnode, "endpoint", &endpoint->id);

	return 0;
}

static const void *
acpi_fwnode_device_get_match_data(const struct fwnode_handle *fwnode,
				  const struct device *dev)
{
	return acpi_device_get_match_data(dev);
}

#define DECLARE_ACPI_FWNODE_OPS(ops) \
	const struct fwnode_operations ops = {				\
		.device_is_available = acpi_fwnode_device_is_available, \
		.device_get_match_data = acpi_fwnode_device_get_match_data, \
		.property_present = acpi_fwnode_property_present,	\
		.property_read_int_array =				\
			acpi_fwnode_property_read_int_array,		\
		.property_read_string_array =				\
			acpi_fwnode_property_read_string_array,		\
		.get_parent = acpi_node_get_parent,			\
		.get_next_child_node = acpi_get_next_subnode,		\
		.get_named_child_node = acpi_fwnode_get_named_child_node, \
		.get_reference_args = acpi_fwnode_get_reference_args,	\
		.graph_get_next_endpoint =				\
			acpi_graph_get_next_endpoint,			\
		.graph_get_remote_endpoint =				\
			acpi_graph_get_remote_endpoint,			\
		.graph_get_port_parent = acpi_fwnode_get_parent,	\
		.graph_parse_endpoint = acpi_fwnode_graph_parse_endpoint, \
	};								\
	EXPORT_SYMBOL_GPL(ops)

DECLARE_ACPI_FWNODE_OPS(acpi_device_fwnode_ops);
DECLARE_ACPI_FWNODE_OPS(acpi_data_fwnode_ops);
const struct fwnode_operations acpi_static_fwnode_ops;

bool is_acpi_device_node(const struct fwnode_handle *fwnode)
{
	return !IS_ERR_OR_NULL(fwnode) &&
		fwnode->ops == &acpi_device_fwnode_ops;
}
EXPORT_SYMBOL(is_acpi_device_node);

bool is_acpi_data_node(const struct fwnode_handle *fwnode)
{
	return !IS_ERR_OR_NULL(fwnode) && fwnode->ops == &acpi_data_fwnode_ops;
}
EXPORT_SYMBOL(is_acpi_data_node);