summaryrefslogtreecommitdiff
path: root/drivers/acpi/acpica/nspredef.c
blob: 309586f5809c71be68785915be1f19142c2ca7e8 (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
/******************************************************************************
 *
 * Module Name: nspredef - Validation of ACPI predefined methods and objects
 *              $Revision: 1.1 $
 *
 *****************************************************************************/

/*
 * Copyright (C) 2000 - 2008, Intel Corp.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer,
 *    without modification.
 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 *    substantially similar to the "NO WARRANTY" disclaimer below
 *    ("Disclaimer") and any redistribution must be conditioned upon
 *    including a substantially similar Disclaimer requirement for further
 *    binary redistribution.
 * 3. Neither the names of the above-listed copyright holders nor the names
 *    of any contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * Alternatively, this software may be distributed under the terms of the
 * GNU General Public License ("GPL") version 2 as published by the Free
 * Software Foundation.
 *
 * NO WARRANTY
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGES.
 */

#define ACPI_CREATE_PREDEFINED_TABLE

#include <acpi/acpi.h>
#include "accommon.h"
#include "acnamesp.h"
#include "acpredef.h"

#define _COMPONENT          ACPI_NAMESPACE
ACPI_MODULE_NAME("nspredef")

/*******************************************************************************
 *
 * This module validates predefined ACPI objects that appear in the namespace,
 * at the time they are evaluated (via acpi_evaluate_object). The purpose of this
 * validation is to detect problems with BIOS-exposed predefined ACPI objects
 * before the results are returned to the ACPI-related drivers.
 *
 * There are several areas that are validated:
 *
 *  1) The number of input arguments as defined by the method/object in the
 *      ASL is validated against the ACPI specification.
 *  2) The type of the return object (if any) is validated against the ACPI
 *      specification.
 *  3) For returned package objects, the count of package elements is
 *      validated, as well as the type of each package element. Nested
 *      packages are supported.
 *
 * For any problems found, a warning message is issued.
 *
 ******************************************************************************/
/* Local prototypes */
static acpi_status
acpi_ns_check_package(struct acpi_predefined_data *data,
		      union acpi_operand_object **return_object_ptr);

static acpi_status
acpi_ns_check_package_list(struct acpi_predefined_data *data,
			   const union acpi_predefined_info *package,
			   union acpi_operand_object **elements, u32 count);

static acpi_status
acpi_ns_check_package_elements(struct acpi_predefined_data *data,
			       union acpi_operand_object **elements,
			       u8 type1,
			       u32 count1,
			       u8 type2, u32 count2, u32 start_index);

static acpi_status
acpi_ns_check_object_type(struct acpi_predefined_data *data,
			  union acpi_operand_object **return_object_ptr,
			  u32 expected_btypes, u32 package_index);

static acpi_status
acpi_ns_check_reference(struct acpi_predefined_data *data,
			union acpi_operand_object *return_object);

static void acpi_ns_get_expected_types(char *buffer, u32 expected_btypes);

/*
 * Names for the types that can be returned by the predefined objects.
 * Used for warning messages. Must be in the same order as the ACPI_RTYPEs
 */
static const char *acpi_rtype_names[] = {
	"/Integer",
	"/String",
	"/Buffer",
	"/Package",
	"/Reference",
};

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_check_predefined_names
 *
 * PARAMETERS:  Node            - Namespace node for the method/object
 *              user_param_count - Number of parameters actually passed
 *              return_status   - Status from the object evaluation
 *              return_object_ptr - Pointer to the object returned from the
 *                                evaluation of a method or object
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Check an ACPI name for a match in the predefined name list.
 *
 ******************************************************************************/

acpi_status
acpi_ns_check_predefined_names(struct acpi_namespace_node *node,
			       u32 user_param_count,
			       acpi_status return_status,
			       union acpi_operand_object **return_object_ptr)
{
	union acpi_operand_object *return_object = *return_object_ptr;
	acpi_status status = AE_OK;
	const union acpi_predefined_info *predefined;
	char *pathname;
	struct acpi_predefined_data *data;

	/* Match the name for this method/object against the predefined list */

	predefined = acpi_ns_check_for_predefined_name(node);

	/* Get the full pathname to the object, for use in warning messages */

	pathname = acpi_ns_get_external_pathname(node);
	if (!pathname) {
		return AE_OK;	/* Could not get pathname, ignore */
	}

	/*
	 * Check that the parameter count for this method matches the ASL
	 * definition. For predefined names, ensure that both the caller and
	 * the method itself are in accordance with the ACPI specification.
	 */
	acpi_ns_check_parameter_count(pathname, node, user_param_count,
				      predefined);

	/* If not a predefined name, we cannot validate the return object */

	if (!predefined) {
		goto cleanup;
	}

	/*
	 * If the method failed or did not actually return an object, we cannot
	 * validate the return object
	 */
	if ((return_status != AE_OK) && (return_status != AE_CTRL_RETURN_VALUE)) {
		goto cleanup;
	}

	/*
	 * If there is no return value, check if we require a return value for
	 * this predefined name. Either one return value is expected, or none,
	 * for both methods and other objects.
	 *
	 * Exit now if there is no return object. Warning if one was expected.
	 */
	if (!return_object) {
		if ((predefined->info.expected_btypes) &&
		    (!(predefined->info.expected_btypes & ACPI_RTYPE_NONE))) {
			ACPI_WARN_PREDEFINED((AE_INFO, pathname,
					      ACPI_WARN_ALWAYS,
					      "Missing expected return value"));

			status = AE_AML_NO_RETURN_VALUE;
		}
		goto cleanup;
	}

	/*
	 * 1) We have a return value, but if one wasn't expected, just exit, this is
	 * not a problem. For example, if the "Implicit Return" feature is
	 * enabled, methods will always return a value.
	 *
	 * 2) If the return value can be of any type, then we cannot perform any
	 * validation, exit.
	 */
	if ((!predefined->info.expected_btypes) ||
	    (predefined->info.expected_btypes == ACPI_RTYPE_ALL)) {
		goto cleanup;
	}

	/* Create the parameter data block for object validation */

	data = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_predefined_data));
	if (!data) {
		goto cleanup;
	}
	data->predefined = predefined;
	data->node_flags = node->flags;
	data->pathname = pathname;

	/*
	 * Check that the type of the main return object is what is expected
	 * for this predefined name
	 */
	status = acpi_ns_check_object_type(data, return_object_ptr,
					   predefined->info.expected_btypes,
					   ACPI_NOT_PACKAGE_ELEMENT);
	if (ACPI_FAILURE(status)) {
		goto exit;
	}

	/*
	 * For returned Package objects, check the type of all sub-objects.
	 * Note: Package may have been newly created by call above.
	 */
	if ((*return_object_ptr)->common.type == ACPI_TYPE_PACKAGE) {
		status = acpi_ns_check_package(data, return_object_ptr);
		if (ACPI_FAILURE(status)) {
			goto exit;
		}
	}

	/*
	 * The return object was OK, or it was successfully repaired above.
	 * Now make some additional checks such as verifying that package
	 * objects are sorted correctly (if required) or buffer objects have
	 * the correct data width (bytes vs. dwords). These repairs are
	 * performed on a per-name basis, i.e., the code is specific to
	 * particular predefined names.
	 */
	status = acpi_ns_complex_repairs(data, node, status, return_object_ptr);

exit:
	/*
	 * If the object validation failed or if we successfully repaired one
	 * or more objects, mark the parent node to suppress further warning
	 * messages during the next evaluation of the same method/object.
	 */
	if (ACPI_FAILURE(status) || (data->flags & ACPI_OBJECT_REPAIRED)) {
		node->flags |= ANOBJ_EVALUATED;
	}
	ACPI_FREE(data);

cleanup:
	ACPI_FREE(pathname);
	return (status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_check_parameter_count
 *
 * PARAMETERS:  Pathname        - Full pathname to the node (for error msgs)
 *              Node            - Namespace node for the method/object
 *              user_param_count - Number of args passed in by the caller
 *              Predefined      - Pointer to entry in predefined name table
 *
 * RETURN:      None
 *
 * DESCRIPTION: Check that the declared (in ASL/AML) parameter count for a
 *              predefined name is what is expected (i.e., what is defined in
 *              the ACPI specification for this predefined name.)
 *
 ******************************************************************************/

void
acpi_ns_check_parameter_count(char *pathname,
			      struct acpi_namespace_node *node,
			      u32 user_param_count,
			      const union acpi_predefined_info *predefined)
{
	u32 param_count;
	u32 required_params_current;
	u32 required_params_old;

	/* Methods have 0-7 parameters. All other types have zero. */

	param_count = 0;
	if (node->type == ACPI_TYPE_METHOD) {
		param_count = node->object->method.param_count;
	}

	if (!predefined) {
		/*
		 * Check the parameter count for non-predefined methods/objects.
		 *
		 * Warning if too few or too many arguments have been passed by the
		 * caller. An incorrect number of arguments may not cause the method
		 * to fail. However, the method will fail if there are too few
		 * arguments and the method attempts to use one of the missing ones.
		 */
		if (user_param_count < param_count) {
			ACPI_WARN_PREDEFINED((AE_INFO, pathname,
					      ACPI_WARN_ALWAYS,
					      "Insufficient arguments - needs %u, found %u",
					      param_count, user_param_count));
		} else if (user_param_count > param_count) {
			ACPI_WARN_PREDEFINED((AE_INFO, pathname,
					      ACPI_WARN_ALWAYS,
					      "Excess arguments - needs %u, found %u",
					      param_count, user_param_count));
		}
		return;
	}

	/*
	 * Validate the user-supplied parameter count.
	 * Allow two different legal argument counts (_SCP, etc.)
	 */
	required_params_current = predefined->info.param_count & 0x0F;
	required_params_old = predefined->info.param_count >> 4;

	if (user_param_count != ACPI_UINT32_MAX) {
		if ((user_param_count != required_params_current) &&
		    (user_param_count != required_params_old)) {
			ACPI_WARN_PREDEFINED((AE_INFO, pathname,
					      ACPI_WARN_ALWAYS,
					      "Parameter count mismatch - "
					      "caller passed %u, ACPI requires %u",
					      user_param_count,
					      required_params_current));
		}
	}

	/*
	 * Check that the ASL-defined parameter count is what is expected for
	 * this predefined name (parameter count as defined by the ACPI
	 * specification)
	 */
	if ((param_count != required_params_current) &&
	    (param_count != required_params_old)) {
		ACPI_WARN_PREDEFINED((AE_INFO, pathname, node->flags,
				      "Parameter count mismatch - ASL declared %u, ACPI requires %u",
				      param_count, required_params_current));
	}
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_check_for_predefined_name
 *
 * PARAMETERS:  Node            - Namespace node for the method/object
 *
 * RETURN:      Pointer to entry in predefined table. NULL indicates not found.
 *
 * DESCRIPTION: Check an object name against the predefined object list.
 *
 ******************************************************************************/

const union acpi_predefined_info *acpi_ns_check_for_predefined_name(struct
								    acpi_namespace_node
								    *node)
{
	const union acpi_predefined_info *this_name;

	/* Quick check for a predefined name, first character must be underscore */

	if (node->name.ascii[0] != '_') {
		return (NULL);
	}

	/* Search info table for a predefined method/object name */

	this_name = predefined_names;
	while (this_name->info.name[0]) {
		if (ACPI_COMPARE_NAME(node->name.ascii, this_name->info.name)) {
			return (this_name);
		}

		/*
		 * Skip next entry in the table if this name returns a Package
		 * (next entry contains the package info)
		 */
		if (this_name->info.expected_btypes & ACPI_RTYPE_PACKAGE) {
			this_name++;
		}

		this_name++;
	}

	return (NULL);		/* Not found */
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_check_package
 *
 * PARAMETERS:  Data            - Pointer to validation data structure
 *              return_object_ptr - Pointer to the object returned from the
 *                                evaluation of a method or object
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Check a returned package object for the correct count and
 *              correct type of all sub-objects.
 *
 ******************************************************************************/

static acpi_status
acpi_ns_check_package(struct acpi_predefined_data *data,
		      union acpi_operand_object **return_object_ptr)
{
	union acpi_operand_object *return_object = *return_object_ptr;
	const union acpi_predefined_info *package;
	union acpi_operand_object **elements;
	acpi_status status = AE_OK;
	u32 expected_count;
	u32 count;
	u32 i;

	ACPI_FUNCTION_NAME(ns_check_package);

	/* The package info for this name is in the next table entry */

	package = data->predefined + 1;

	ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
			  "%s Validating return Package of Type %X, Count %X\n",
			  data->pathname, package->ret_info.type,
			  return_object->package.count));

	/*
	 * For variable-length Packages, we can safely remove all embedded
	 * and trailing NULL package elements
	 */
	acpi_ns_remove_null_elements(data, package->ret_info.type,
				     return_object);

	/* Extract package count and elements array */

	elements = return_object->package.elements;
	count = return_object->package.count;

	/* The package must have at least one element, else invalid */

	if (!count) {
		ACPI_WARN_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
				      "Return Package has no elements (empty)"));

		return (AE_AML_OPERAND_VALUE);
	}

	/*
	 * Decode the type of the expected package contents
	 *
	 * PTYPE1 packages contain no subpackages
	 * PTYPE2 packages contain sub-packages
	 */
	switch (package->ret_info.type) {
	case ACPI_PTYPE1_FIXED:

		/*
		 * The package count is fixed and there are no sub-packages
		 *
		 * If package is too small, exit.
		 * If package is larger than expected, issue warning but continue
		 */
		expected_count =
		    package->ret_info.count1 + package->ret_info.count2;
		if (count < expected_count) {
			goto package_too_small;
		} else if (count > expected_count) {
			ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
					  "%s: Return Package is larger than needed - "
					  "found %u, expected %u\n",
					  data->pathname, count,
					  expected_count));
		}

		/* Validate all elements of the returned package */

		status = acpi_ns_check_package_elements(data, elements,
							package->ret_info.
							object_type1,
							package->ret_info.
							count1,
							package->ret_info.
							object_type2,
							package->ret_info.
							count2, 0);
		break;

	case ACPI_PTYPE1_VAR:

		/*
		 * The package count is variable, there are no sub-packages, and all
		 * elements must be of the same type
		 */
		for (i = 0; i < count; i++) {
			status = acpi_ns_check_object_type(data, elements,
							   package->ret_info.
							   object_type1, i);
			if (ACPI_FAILURE(status)) {
				return (status);
			}
			elements++;
		}
		break;

	case ACPI_PTYPE1_OPTION:

		/*
		 * The package count is variable, there are no sub-packages. There are
		 * a fixed number of required elements, and a variable number of
		 * optional elements.
		 *
		 * Check if package is at least as large as the minimum required
		 */
		expected_count = package->ret_info3.count;
		if (count < expected_count) {
			goto package_too_small;
		}

		/* Variable number of sub-objects */

		for (i = 0; i < count; i++) {
			if (i < package->ret_info3.count) {

				/* These are the required package elements (0, 1, or 2) */

				status =
				    acpi_ns_check_object_type(data, elements,
							      package->
							      ret_info3.
							      object_type[i],
							      i);
				if (ACPI_FAILURE(status)) {
					return (status);
				}
			} else {
				/* These are the optional package elements */

				status =
				    acpi_ns_check_object_type(data, elements,
							      package->
							      ret_info3.
							      tail_object_type,
							      i);
				if (ACPI_FAILURE(status)) {
					return (status);
				}
			}
			elements++;
		}
		break;

	case ACPI_PTYPE2_REV_FIXED:

		/* First element is the (Integer) revision */

		status = acpi_ns_check_object_type(data, elements,
						   ACPI_RTYPE_INTEGER, 0);
		if (ACPI_FAILURE(status)) {
			return (status);
		}

		elements++;
		count--;

		/* Examine the sub-packages */

		status =
		    acpi_ns_check_package_list(data, package, elements, count);
		break;

	case ACPI_PTYPE2_PKG_COUNT:

		/* First element is the (Integer) count of sub-packages to follow */

		status = acpi_ns_check_object_type(data, elements,
						   ACPI_RTYPE_INTEGER, 0);
		if (ACPI_FAILURE(status)) {
			return (status);
		}

		/*
		 * Count cannot be larger than the parent package length, but allow it
		 * to be smaller. The >= accounts for the Integer above.
		 */
		expected_count = (u32) (*elements)->integer.value;
		if (expected_count >= count) {
			goto package_too_small;
		}

		count = expected_count;
		elements++;

		/* Examine the sub-packages */

		status =
		    acpi_ns_check_package_list(data, package, elements, count);
		break;

	case ACPI_PTYPE2:
	case ACPI_PTYPE2_FIXED:
	case ACPI_PTYPE2_MIN:
	case ACPI_PTYPE2_COUNT:

		/*
		 * These types all return a single Package that consists of a
		 * variable number of sub-Packages.
		 *
		 * First, ensure that the first element is a sub-Package. If not,
		 * the BIOS may have incorrectly returned the object as a single
		 * package instead of a Package of Packages (a common error if
		 * there is only one entry). We may be able to repair this by
		 * wrapping the returned Package with a new outer Package.
		 */
		if (*elements
		    && ((*elements)->common.type != ACPI_TYPE_PACKAGE)) {

			/* Create the new outer package and populate it */

			status =
			    acpi_ns_repair_package_list(data,
							return_object_ptr);
			if (ACPI_FAILURE(status)) {
				return (status);
			}

			/* Update locals to point to the new package (of 1 element) */

			return_object = *return_object_ptr;
			elements = return_object->package.elements;
			count = 1;
		}

		/* Examine the sub-packages */

		status =
		    acpi_ns_check_package_list(data, package, elements, count);
		break;

	default:

		/* Should not get here if predefined info table is correct */

		ACPI_WARN_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
				      "Invalid internal return type in table entry: %X",
				      package->ret_info.type));

		return (AE_AML_INTERNAL);
	}

	return (status);

package_too_small:

	/* Error exit for the case with an incorrect package count */

	ACPI_WARN_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
			      "Return Package is too small - found %u elements, expected %u",
			      count, expected_count));

	return (AE_AML_OPERAND_VALUE);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_check_package_list
 *
 * PARAMETERS:  Data            - Pointer to validation data structure
 *              Package         - Pointer to package-specific info for method
 *              Elements        - Element list of parent package. All elements
 *                                of this list should be of type Package.
 *              Count           - Count of subpackages
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Examine a list of subpackages
 *
 ******************************************************************************/

static acpi_status
acpi_ns_check_package_list(struct acpi_predefined_data *data,
			   const union acpi_predefined_info *package,
			   union acpi_operand_object **elements, u32 count)
{
	union acpi_operand_object *sub_package;
	union acpi_operand_object **sub_elements;
	acpi_status status;
	u32 expected_count;
	u32 i;
	u32 j;

	/*
	 * Validate each sub-Package in the parent Package
	 *
	 * NOTE: assumes list of sub-packages contains no NULL elements.
	 * Any NULL elements should have been removed by earlier call
	 * to acpi_ns_remove_null_elements.
	 */
	for (i = 0; i < count; i++) {
		sub_package = *elements;
		sub_elements = sub_package->package.elements;

		/* Each sub-object must be of type Package */

		status = acpi_ns_check_object_type(data, &sub_package,
						   ACPI_RTYPE_PACKAGE, i);
		if (ACPI_FAILURE(status)) {
			return (status);
		}

		/* Examine the different types of expected sub-packages */

		switch (package->ret_info.type) {
		case ACPI_PTYPE2:
		case ACPI_PTYPE2_PKG_COUNT:
		case ACPI_PTYPE2_REV_FIXED:

			/* Each subpackage has a fixed number of elements */

			expected_count =
			    package->ret_info.count1 + package->ret_info.count2;
			if (sub_package->package.count < expected_count) {
				goto package_too_small;
			}

			status =
			    acpi_ns_check_package_elements(data, sub_elements,
							   package->ret_info.
							   object_type1,
							   package->ret_info.
							   count1,
							   package->ret_info.
							   object_type2,
							   package->ret_info.
							   count2, 0);
			if (ACPI_FAILURE(status)) {
				return (status);
			}
			break;

		case ACPI_PTYPE2_FIXED:

			/* Each sub-package has a fixed length */

			expected_count = package->ret_info2.count;
			if (sub_package->package.count < expected_count) {
				goto package_too_small;
			}

			/* Check the type of each sub-package element */

			for (j = 0; j < expected_count; j++) {
				status =
				    acpi_ns_check_object_type(data,
							      &sub_elements[j],
							      package->
							      ret_info2.
							      object_type[j],
							      j);
				if (ACPI_FAILURE(status)) {
					return (status);
				}
			}
			break;

		case ACPI_PTYPE2_MIN:

			/* Each sub-package has a variable but minimum length */

			expected_count = package->ret_info.count1;
			if (sub_package->package.count < expected_count) {
				goto package_too_small;
			}

			/* Check the type of each sub-package element */

			status =
			    acpi_ns_check_package_elements(data, sub_elements,
							   package->ret_info.
							   object_type1,
							   sub_package->package.
							   count, 0, 0, 0);
			if (ACPI_FAILURE(status)) {
				return (status);
			}
			break;

		case ACPI_PTYPE2_COUNT:

			/*
			 * First element is the (Integer) count of elements, including
			 * the count field.
			 */
			status = acpi_ns_check_object_type(data, sub_elements,
							   ACPI_RTYPE_INTEGER,
							   0);
			if (ACPI_FAILURE(status)) {
				return (status);
			}

			/*
			 * Make sure package is large enough for the Count and is
			 * is as large as the minimum size
			 */
			expected_count = (u32)(*sub_elements)->integer.value;
			if (sub_package->package.count < expected_count) {
				goto package_too_small;
			}
			if (sub_package->package.count <
			    package->ret_info.count1) {
				expected_count = package->ret_info.count1;
				goto package_too_small;
			}

			/* Check the type of each sub-package element */

			status =
			    acpi_ns_check_package_elements(data,
							   (sub_elements + 1),
							   package->ret_info.
							   object_type1,
							   (expected_count - 1),
							   0, 0, 1);
			if (ACPI_FAILURE(status)) {
				return (status);
			}
			break;

		default:	/* Should not get here, type was validated by caller */

			return (AE_AML_INTERNAL);
		}

		elements++;
	}

	return (AE_OK);

package_too_small:

	/* The sub-package count was smaller than required */

	ACPI_WARN_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
			      "Return Sub-Package[%u] is too small - found %u elements, expected %u",
			      i, sub_package->package.count, expected_count));

	return (AE_AML_OPERAND_VALUE);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_check_package_elements
 *
 * PARAMETERS:  Data            - Pointer to validation data structure
 *              Elements        - Pointer to the package elements array
 *              Type1           - Object type for first group
 *              Count1          - Count for first group
 *              Type2           - Object type for second group
 *              Count2          - Count for second group
 *              start_index     - Start of the first group of elements
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Check that all elements of a package are of the correct object
 *              type. Supports up to two groups of different object types.
 *
 ******************************************************************************/

static acpi_status
acpi_ns_check_package_elements(struct acpi_predefined_data *data,
			       union acpi_operand_object **elements,
			       u8 type1,
			       u32 count1,
			       u8 type2, u32 count2, u32 start_index)
{
	union acpi_operand_object **this_element = elements;
	acpi_status status;
	u32 i;

	/*
	 * Up to two groups of package elements are supported by the data
	 * structure. All elements in each group must be of the same type.
	 * The second group can have a count of zero.
	 */
	for (i = 0; i < count1; i++) {
		status = acpi_ns_check_object_type(data, this_element,
						   type1, i + start_index);
		if (ACPI_FAILURE(status)) {
			return (status);
		}
		this_element++;
	}

	for (i = 0; i < count2; i++) {
		status = acpi_ns_check_object_type(data, this_element,
						   type2,
						   (i + count1 + start_index));
		if (ACPI_FAILURE(status)) {
			return (status);
		}
		this_element++;
	}

	return (AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_check_object_type
 *
 * PARAMETERS:  Data            - Pointer to validation data structure
 *              return_object_ptr - Pointer to the object returned from the
 *                                evaluation of a method or object
 *              expected_btypes - Bitmap of expected return type(s)
 *              package_index   - Index of object within parent package (if
 *                                applicable - ACPI_NOT_PACKAGE_ELEMENT
 *                                otherwise)
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Check the type of the return object against the expected object
 *              type(s). Use of Btype allows multiple expected object types.
 *
 ******************************************************************************/

static acpi_status
acpi_ns_check_object_type(struct acpi_predefined_data *data,
			  union acpi_operand_object **return_object_ptr,
			  u32 expected_btypes, u32 package_index)
{
	union acpi_operand_object *return_object = *return_object_ptr;
	acpi_status status = AE_OK;
	u32 return_btype;
	char type_buffer[48];	/* Room for 5 types */

	/*
	 * If we get a NULL return_object here, it is a NULL package element,
	 * and this is always an error.
	 */
	if (!return_object) {
		goto type_error_exit;
	}

	/* A Namespace node should not get here, but make sure */

	if (ACPI_GET_DESCRIPTOR_TYPE(return_object) == ACPI_DESC_TYPE_NAMED) {
		ACPI_WARN_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
				      "Invalid return type - Found a Namespace node [%4.4s] type %s",
				      return_object->node.name.ascii,
				      acpi_ut_get_type_name(return_object->node.
							    type)));
		return (AE_AML_OPERAND_TYPE);
	}

	/*
	 * Convert the object type (ACPI_TYPE_xxx) to a bitmapped object type.
	 * The bitmapped type allows multiple possible return types.
	 *
	 * Note, the cases below must handle all of the possible types returned
	 * from all of the predefined names (including elements of returned
	 * packages)
	 */
	switch (return_object->common.type) {
	case ACPI_TYPE_INTEGER:
		return_btype = ACPI_RTYPE_INTEGER;
		break;

	case ACPI_TYPE_BUFFER:
		return_btype = ACPI_RTYPE_BUFFER;
		break;

	case ACPI_TYPE_STRING:
		return_btype = ACPI_RTYPE_STRING;
		break;

	case ACPI_TYPE_PACKAGE:
		return_btype = ACPI_RTYPE_PACKAGE;
		break;

	case ACPI_TYPE_LOCAL_REFERENCE:
		return_btype = ACPI_RTYPE_REFERENCE;
		break;

	default:
		/* Not one of the supported objects, must be incorrect */

		goto type_error_exit;
	}

	/* Is the object one of the expected types? */

	if (return_btype & expected_btypes) {

		/* For reference objects, check that the reference type is correct */

		if (return_object->common.type == ACPI_TYPE_LOCAL_REFERENCE) {
			status = acpi_ns_check_reference(data, return_object);
		}

		return (status);
	}

	/* Type mismatch -- attempt repair of the returned object */

	status = acpi_ns_repair_object(data, expected_btypes,
				       package_index, return_object_ptr);
	if (ACPI_SUCCESS(status)) {
		return (AE_OK);	/* Repair was successful */
	}

      type_error_exit:

	/* Create a string with all expected types for this predefined object */

	acpi_ns_get_expected_types(type_buffer, expected_btypes);

	if (package_index == ACPI_NOT_PACKAGE_ELEMENT) {
		ACPI_WARN_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
				      "Return type mismatch - found %s, expected %s",
				      acpi_ut_get_object_type_name
				      (return_object), type_buffer));
	} else {
		ACPI_WARN_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
				      "Return Package type mismatch at index %u - "
				      "found %s, expected %s", package_index,
				      acpi_ut_get_object_type_name
				      (return_object), type_buffer));
	}

	return (AE_AML_OPERAND_TYPE);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_check_reference
 *
 * PARAMETERS:  Data            - Pointer to validation data structure
 *              return_object   - Object returned from the evaluation of a
 *                                method or object
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Check a returned reference object for the correct reference
 *              type. The only reference type that can be returned from a
 *              predefined method is a named reference. All others are invalid.
 *
 ******************************************************************************/

static acpi_status
acpi_ns_check_reference(struct acpi_predefined_data *data,
			union acpi_operand_object *return_object)
{

	/*
	 * Check the reference object for the correct reference type (opcode).
	 * The only type of reference that can be converted to an union acpi_object is
	 * a reference to a named object (reference class: NAME)
	 */
	if (return_object->reference.class == ACPI_REFCLASS_NAME) {
		return (AE_OK);
	}

	ACPI_WARN_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
			      "Return type mismatch - unexpected reference object type [%s] %2.2X",
			      acpi_ut_get_reference_name(return_object),
			      return_object->reference.class));

	return (AE_AML_OPERAND_TYPE);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_get_expected_types
 *
 * PARAMETERS:  Buffer          - Pointer to where the string is returned
 *              expected_btypes - Bitmap of expected return type(s)
 *
 * RETURN:      Buffer is populated with type names.
 *
 * DESCRIPTION: Translate the expected types bitmap into a string of ascii
 *              names of expected types, for use in warning messages.
 *
 ******************************************************************************/

static void acpi_ns_get_expected_types(char *buffer, u32 expected_btypes)
{
	u32 this_rtype;
	u32 i;
	u32 j;

	j = 1;
	buffer[0] = 0;
	this_rtype = ACPI_RTYPE_INTEGER;

	for (i = 0; i < ACPI_NUM_RTYPES; i++) {

		/* If one of the expected types, concatenate the name of this type */

		if (expected_btypes & this_rtype) {
			ACPI_STRCAT(buffer, &acpi_rtype_names[i][j]);
			j = 0;	/* Use name separator from now on */
		}
		this_rtype <<= 1;	/* Next Rtype */
	}
}