xref: /openbmc/linux/drivers/acpi/acpica/nspredef.c (revision fd589a8f)
1 /******************************************************************************
2  *
3  * Module Name: nspredef - Validation of ACPI predefined methods and objects
4  *              $Revision: 1.1 $
5  *
6  *****************************************************************************/
7 
8 /*
9  * Copyright (C) 2000 - 2008, Intel Corp.
10  * All rights reserved.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions, and the following disclaimer,
17  *    without modification.
18  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
19  *    substantially similar to the "NO WARRANTY" disclaimer below
20  *    ("Disclaimer") and any redistribution must be conditioned upon
21  *    including a substantially similar Disclaimer requirement for further
22  *    binary redistribution.
23  * 3. Neither the names of the above-listed copyright holders nor the names
24  *    of any contributors may be used to endorse or promote products derived
25  *    from this software without specific prior written permission.
26  *
27  * Alternatively, this software may be distributed under the terms of the
28  * GNU General Public License ("GPL") version 2 as published by the Free
29  * Software Foundation.
30  *
31  * NO WARRANTY
32  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
33  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
34  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
35  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
36  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
37  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
38  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
39  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
40  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
41  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
42  * POSSIBILITY OF SUCH DAMAGES.
43  */
44 
45 #include <acpi/acpi.h>
46 #include "accommon.h"
47 #include "acnamesp.h"
48 #include "acpredef.h"
49 
50 #define _COMPONENT          ACPI_NAMESPACE
51 ACPI_MODULE_NAME("nspredef")
52 
53 /*******************************************************************************
54  *
55  * This module validates predefined ACPI objects that appear in the namespace,
56  * at the time they are evaluated (via acpi_evaluate_object). The purpose of this
57  * validation is to detect problems with BIOS-exposed predefined ACPI objects
58  * before the results are returned to the ACPI-related drivers.
59  *
60  * There are several areas that are validated:
61  *
62  *  1) The number of input arguments as defined by the method/object in the
63  *      ASL is validated against the ACPI specification.
64  *  2) The type of the return object (if any) is validated against the ACPI
65  *      specification.
66  *  3) For returned package objects, the count of package elements is
67  *      validated, as well as the type of each package element. Nested
68  *      packages are supported.
69  *
70  * For any problems found, a warning message is issued.
71  *
72  ******************************************************************************/
73 /* Local prototypes */
74 static acpi_status
75 acpi_ns_check_package(char *pathname,
76 		      union acpi_operand_object **return_object_ptr,
77 		      const union acpi_predefined_info *predefined);
78 
79 static acpi_status
80 acpi_ns_check_package_elements(char *pathname,
81 			       union acpi_operand_object **elements,
82 			       u8 type1,
83 			       u32 count1,
84 			       u8 type2, u32 count2, u32 start_index);
85 
86 static acpi_status
87 acpi_ns_check_object_type(char *pathname,
88 			  union acpi_operand_object **return_object_ptr,
89 			  u32 expected_btypes, u32 package_index);
90 
91 static acpi_status
92 acpi_ns_check_reference(char *pathname,
93 			union acpi_operand_object *return_object);
94 
95 static acpi_status
96 acpi_ns_repair_object(u32 expected_btypes,
97 		      u32 package_index,
98 		      union acpi_operand_object **return_object_ptr);
99 
100 /*
101  * Names for the types that can be returned by the predefined objects.
102  * Used for warning messages. Must be in the same order as the ACPI_RTYPEs
103  */
104 static const char *acpi_rtype_names[] = {
105 	"/Integer",
106 	"/String",
107 	"/Buffer",
108 	"/Package",
109 	"/Reference",
110 };
111 
112 #define ACPI_NOT_PACKAGE    ACPI_UINT32_MAX
113 
114 /*******************************************************************************
115  *
116  * FUNCTION:    acpi_ns_check_predefined_names
117  *
118  * PARAMETERS:  Node            - Namespace node for the method/object
119  *              return_object_ptr - Pointer to the object returned from the
120  *                                evaluation of a method or object
121  *
122  * RETURN:      Status
123  *
124  * DESCRIPTION: Check an ACPI name for a match in the predefined name list.
125  *
126  ******************************************************************************/
127 
128 acpi_status
129 acpi_ns_check_predefined_names(struct acpi_namespace_node *node,
130 			       u32 user_param_count,
131 			       acpi_status return_status,
132 			       union acpi_operand_object **return_object_ptr)
133 {
134 	union acpi_operand_object *return_object = *return_object_ptr;
135 	acpi_status status = AE_OK;
136 	const union acpi_predefined_info *predefined;
137 	char *pathname;
138 
139 	/* Match the name for this method/object against the predefined list */
140 
141 	predefined = acpi_ns_check_for_predefined_name(node);
142 
143 	/* Get the full pathname to the object, for use in error messages */
144 
145 	pathname = acpi_ns_get_external_pathname(node);
146 	if (!pathname) {
147 		return AE_OK;	/* Could not get pathname, ignore */
148 	}
149 
150 	/*
151 	 * Check that the parameter count for this method matches the ASL
152 	 * definition. For predefined names, ensure that both the caller and
153 	 * the method itself are in accordance with the ACPI specification.
154 	 */
155 	acpi_ns_check_parameter_count(pathname, node, user_param_count,
156 				      predefined);
157 
158 	/* If not a predefined name, we cannot validate the return object */
159 
160 	if (!predefined) {
161 		goto exit;
162 	}
163 
164 	/* If the method failed, we cannot validate the return object */
165 
166 	if ((return_status != AE_OK) && (return_status != AE_CTRL_RETURN_VALUE)) {
167 		goto exit;
168 	}
169 
170 	/*
171 	 * Only validate the return value on the first successful evaluation of
172 	 * the method. This ensures that any warnings will only be emitted during
173 	 * the very first evaluation of the method/object.
174 	 */
175 	if (node->flags & ANOBJ_EVALUATED) {
176 		goto exit;
177 	}
178 
179 	/* Mark the node as having been successfully evaluated */
180 
181 	node->flags |= ANOBJ_EVALUATED;
182 
183 	/*
184 	 * If there is no return value, check if we require a return value for
185 	 * this predefined name. Either one return value is expected, or none,
186 	 * for both methods and other objects.
187 	 *
188 	 * Exit now if there is no return object. Warning if one was expected.
189 	 */
190 	if (!return_object) {
191 		if ((predefined->info.expected_btypes) &&
192 		    (!(predefined->info.expected_btypes & ACPI_RTYPE_NONE))) {
193 			ACPI_ERROR((AE_INFO,
194 				    "%s: Missing expected return value",
195 				    pathname));
196 
197 			status = AE_AML_NO_RETURN_VALUE;
198 		}
199 		goto exit;
200 	}
201 
202 	/*
203 	 * We have a return value, but if one wasn't expected, just exit, this is
204 	 * not a problem
205 	 *
206 	 * For example, if the "Implicit Return" feature is enabled, methods will
207 	 * always return a value
208 	 */
209 	if (!predefined->info.expected_btypes) {
210 		goto exit;
211 	}
212 
213 	/*
214 	 * Check that the type of the return object is what is expected for
215 	 * this predefined name
216 	 */
217 	status = acpi_ns_check_object_type(pathname, return_object_ptr,
218 					   predefined->info.expected_btypes,
219 					   ACPI_NOT_PACKAGE);
220 	if (ACPI_FAILURE(status)) {
221 		goto exit;
222 	}
223 
224 	/* For returned Package objects, check the type of all sub-objects */
225 
226 	if (return_object->common.type == ACPI_TYPE_PACKAGE) {
227 		status =
228 		    acpi_ns_check_package(pathname, return_object_ptr,
229 					  predefined);
230 	}
231 
232       exit:
233 	ACPI_FREE(pathname);
234 	return (status);
235 }
236 
237 /*******************************************************************************
238  *
239  * FUNCTION:    acpi_ns_check_parameter_count
240  *
241  * PARAMETERS:  Pathname        - Full pathname to the node (for error msgs)
242  *              Node            - Namespace node for the method/object
243  *              user_param_count - Number of args passed in by the caller
244  *              Predefined      - Pointer to entry in predefined name table
245  *
246  * RETURN:      None
247  *
248  * DESCRIPTION: Check that the declared (in ASL/AML) parameter count for a
249  *              predefined name is what is expected (i.e., what is defined in
250  *              the ACPI specification for this predefined name.)
251  *
252  ******************************************************************************/
253 
254 void
255 acpi_ns_check_parameter_count(char *pathname,
256 			      struct acpi_namespace_node *node,
257 			      u32 user_param_count,
258 			      const union acpi_predefined_info *predefined)
259 {
260 	u32 param_count;
261 	u32 required_params_current;
262 	u32 required_params_old;
263 
264 	/* Methods have 0-7 parameters. All other types have zero. */
265 
266 	param_count = 0;
267 	if (node->type == ACPI_TYPE_METHOD) {
268 		param_count = node->object->method.param_count;
269 	}
270 
271 	/* Argument count check for non-predefined methods/objects */
272 
273 	if (!predefined) {
274 		/*
275 		 * Warning if too few or too many arguments have been passed by the
276 		 * caller. An incorrect number of arguments may not cause the method
277 		 * to fail. However, the method will fail if there are too few
278 		 * arguments and the method attempts to use one of the missing ones.
279 		 */
280 		if (user_param_count < param_count) {
281 			ACPI_WARNING((AE_INFO,
282 				      "%s: Insufficient arguments - needs %d, found %d",
283 				      pathname, param_count, user_param_count));
284 		} else if (user_param_count > param_count) {
285 			ACPI_WARNING((AE_INFO,
286 				      "%s: Excess arguments - needs %d, found %d",
287 				      pathname, param_count, user_param_count));
288 		}
289 		return;
290 	}
291 
292 	/* Allow two different legal argument counts (_SCP, etc.) */
293 
294 	required_params_current = predefined->info.param_count & 0x0F;
295 	required_params_old = predefined->info.param_count >> 4;
296 
297 	if (user_param_count != ACPI_UINT32_MAX) {
298 
299 		/* Validate the user-supplied parameter count */
300 
301 		if ((user_param_count != required_params_current) &&
302 		    (user_param_count != required_params_old)) {
303 			ACPI_WARNING((AE_INFO,
304 				      "%s: Parameter count mismatch - "
305 				      "caller passed %d, ACPI requires %d",
306 				      pathname, user_param_count,
307 				      required_params_current));
308 		}
309 	}
310 
311 	/*
312 	 * Only validate the argument count on the first successful evaluation of
313 	 * the method. This ensures that any warnings will only be emitted during
314 	 * the very first evaluation of the method/object.
315 	 */
316 	if (node->flags & ANOBJ_EVALUATED) {
317 		return;
318 	}
319 
320 	/*
321 	 * Check that the ASL-defined parameter count is what is expected for
322 	 * this predefined name.
323 	 */
324 	if ((param_count != required_params_current) &&
325 	    (param_count != required_params_old)) {
326 		ACPI_WARNING((AE_INFO,
327 			      "%s: Parameter count mismatch - ASL declared %d, ACPI requires %d",
328 			      pathname, param_count, required_params_current));
329 	}
330 }
331 
332 /*******************************************************************************
333  *
334  * FUNCTION:    acpi_ns_check_for_predefined_name
335  *
336  * PARAMETERS:  Node            - Namespace node for the method/object
337  *
338  * RETURN:      Pointer to entry in predefined table. NULL indicates not found.
339  *
340  * DESCRIPTION: Check an object name against the predefined object list.
341  *
342  ******************************************************************************/
343 
344 const union acpi_predefined_info *acpi_ns_check_for_predefined_name(struct
345 								    acpi_namespace_node
346 								    *node)
347 {
348 	const union acpi_predefined_info *this_name;
349 
350 	/* Quick check for a predefined name, first character must be underscore */
351 
352 	if (node->name.ascii[0] != '_') {
353 		return (NULL);
354 	}
355 
356 	/* Search info table for a predefined method/object name */
357 
358 	this_name = predefined_names;
359 	while (this_name->info.name[0]) {
360 		if (ACPI_COMPARE_NAME(node->name.ascii, this_name->info.name)) {
361 
362 			/* Return pointer to this table entry */
363 
364 			return (this_name);
365 		}
366 
367 		/*
368 		 * Skip next entry in the table if this name returns a Package
369 		 * (next entry contains the package info)
370 		 */
371 		if (this_name->info.expected_btypes & ACPI_RTYPE_PACKAGE) {
372 			this_name++;
373 		}
374 
375 		this_name++;
376 	}
377 
378 	return (NULL);
379 }
380 
381 /*******************************************************************************
382  *
383  * FUNCTION:    acpi_ns_check_package
384  *
385  * PARAMETERS:  Pathname        - Full pathname to the node (for error msgs)
386  *              return_object_ptr - Pointer to the object returned from the
387  *                                evaluation of a method or object
388  *              Predefined      - Pointer to entry in predefined name table
389  *
390  * RETURN:      Status
391  *
392  * DESCRIPTION: Check a returned package object for the correct count and
393  *              correct type of all sub-objects.
394  *
395  ******************************************************************************/
396 
397 static acpi_status
398 acpi_ns_check_package(char *pathname,
399 		      union acpi_operand_object **return_object_ptr,
400 		      const union acpi_predefined_info *predefined)
401 {
402 	union acpi_operand_object *return_object = *return_object_ptr;
403 	const union acpi_predefined_info *package;
404 	union acpi_operand_object *sub_package;
405 	union acpi_operand_object **elements;
406 	union acpi_operand_object **sub_elements;
407 	acpi_status status;
408 	u32 expected_count;
409 	u32 count;
410 	u32 i;
411 	u32 j;
412 
413 	ACPI_FUNCTION_NAME(ns_check_package);
414 
415 	/* The package info for this name is in the next table entry */
416 
417 	package = predefined + 1;
418 
419 	ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
420 			  "%s Validating return Package of Type %X, Count %X\n",
421 			  pathname, package->ret_info.type,
422 			  return_object->package.count));
423 
424 	/* Extract package count and elements array */
425 
426 	elements = return_object->package.elements;
427 	count = return_object->package.count;
428 
429 	/* The package must have at least one element, else invalid */
430 
431 	if (!count) {
432 		ACPI_WARNING((AE_INFO,
433 			      "%s: Return Package has no elements (empty)",
434 			      pathname));
435 
436 		return (AE_AML_OPERAND_VALUE);
437 	}
438 
439 	/*
440 	 * Decode the type of the expected package contents
441 	 *
442 	 * PTYPE1 packages contain no subpackages
443 	 * PTYPE2 packages contain sub-packages
444 	 */
445 	switch (package->ret_info.type) {
446 	case ACPI_PTYPE1_FIXED:
447 
448 		/*
449 		 * The package count is fixed and there are no sub-packages
450 		 *
451 		 * If package is too small, exit.
452 		 * If package is larger than expected, issue warning but continue
453 		 */
454 		expected_count =
455 		    package->ret_info.count1 + package->ret_info.count2;
456 		if (count < expected_count) {
457 			goto package_too_small;
458 		} else if (count > expected_count) {
459 			ACPI_WARNING((AE_INFO,
460 				      "%s: Return Package is larger than needed - "
461 				      "found %u, expected %u", pathname, count,
462 				      expected_count));
463 		}
464 
465 		/* Validate all elements of the returned package */
466 
467 		status = acpi_ns_check_package_elements(pathname, elements,
468 							package->ret_info.
469 							object_type1,
470 							package->ret_info.
471 							count1,
472 							package->ret_info.
473 							object_type2,
474 							package->ret_info.
475 							count2, 0);
476 		if (ACPI_FAILURE(status)) {
477 			return (status);
478 		}
479 		break;
480 
481 	case ACPI_PTYPE1_VAR:
482 
483 		/*
484 		 * The package count is variable, there are no sub-packages, and all
485 		 * elements must be of the same type
486 		 */
487 		for (i = 0; i < count; i++) {
488 			status = acpi_ns_check_object_type(pathname, elements,
489 							   package->ret_info.
490 							   object_type1, i);
491 			if (ACPI_FAILURE(status)) {
492 				return (status);
493 			}
494 			elements++;
495 		}
496 		break;
497 
498 	case ACPI_PTYPE1_OPTION:
499 
500 		/*
501 		 * The package count is variable, there are no sub-packages. There are
502 		 * a fixed number of required elements, and a variable number of
503 		 * optional elements.
504 		 *
505 		 * Check if package is at least as large as the minimum required
506 		 */
507 		expected_count = package->ret_info3.count;
508 		if (count < expected_count) {
509 			goto package_too_small;
510 		}
511 
512 		/* Variable number of sub-objects */
513 
514 		for (i = 0; i < count; i++) {
515 			if (i < package->ret_info3.count) {
516 
517 				/* These are the required package elements (0, 1, or 2) */
518 
519 				status =
520 				    acpi_ns_check_object_type(pathname,
521 							      elements,
522 							      package->
523 							      ret_info3.
524 							      object_type[i],
525 							      i);
526 				if (ACPI_FAILURE(status)) {
527 					return (status);
528 				}
529 			} else {
530 				/* These are the optional package elements */
531 
532 				status =
533 				    acpi_ns_check_object_type(pathname,
534 							      elements,
535 							      package->
536 							      ret_info3.
537 							      tail_object_type,
538 							      i);
539 				if (ACPI_FAILURE(status)) {
540 					return (status);
541 				}
542 			}
543 			elements++;
544 		}
545 		break;
546 
547 	case ACPI_PTYPE2_PKG_COUNT:
548 
549 		/* First element is the (Integer) count of sub-packages to follow */
550 
551 		status = acpi_ns_check_object_type(pathname, elements,
552 						   ACPI_RTYPE_INTEGER, 0);
553 		if (ACPI_FAILURE(status)) {
554 			return (status);
555 		}
556 
557 		/*
558 		 * Count cannot be larger than the parent package length, but allow it
559 		 * to be smaller. The >= accounts for the Integer above.
560 		 */
561 		expected_count = (u32) (*elements)->integer.value;
562 		if (expected_count >= count) {
563 			goto package_too_small;
564 		}
565 
566 		count = expected_count;
567 		elements++;
568 
569 		/* Now we can walk the sub-packages */
570 
571 		/*lint -fallthrough */
572 
573 	case ACPI_PTYPE2:
574 	case ACPI_PTYPE2_FIXED:
575 	case ACPI_PTYPE2_MIN:
576 	case ACPI_PTYPE2_COUNT:
577 
578 		/*
579 		 * These types all return a single package that consists of a variable
580 		 * number of sub-packages
581 		 */
582 		for (i = 0; i < count; i++) {
583 			sub_package = *elements;
584 			sub_elements = sub_package->package.elements;
585 
586 			/* Each sub-object must be of type Package */
587 
588 			status =
589 			    acpi_ns_check_object_type(pathname, &sub_package,
590 						      ACPI_RTYPE_PACKAGE, i);
591 			if (ACPI_FAILURE(status)) {
592 				return (status);
593 			}
594 
595 			/* Examine the different types of sub-packages */
596 
597 			switch (package->ret_info.type) {
598 			case ACPI_PTYPE2:
599 			case ACPI_PTYPE2_PKG_COUNT:
600 
601 				/* Each subpackage has a fixed number of elements */
602 
603 				expected_count =
604 				    package->ret_info.count1 +
605 				    package->ret_info.count2;
606 				if (sub_package->package.count !=
607 				    expected_count) {
608 					count = sub_package->package.count;
609 					goto package_too_small;
610 				}
611 
612 				status =
613 				    acpi_ns_check_package_elements(pathname,
614 								   sub_elements,
615 								   package->
616 								   ret_info.
617 								   object_type1,
618 								   package->
619 								   ret_info.
620 								   count1,
621 								   package->
622 								   ret_info.
623 								   object_type2,
624 								   package->
625 								   ret_info.
626 								   count2, 0);
627 				if (ACPI_FAILURE(status)) {
628 					return (status);
629 				}
630 				break;
631 
632 			case ACPI_PTYPE2_FIXED:
633 
634 				/* Each sub-package has a fixed length */
635 
636 				expected_count = package->ret_info2.count;
637 				if (sub_package->package.count < expected_count) {
638 					count = sub_package->package.count;
639 					goto package_too_small;
640 				}
641 
642 				/* Check the type of each sub-package element */
643 
644 				for (j = 0; j < expected_count; j++) {
645 					status =
646 					    acpi_ns_check_object_type(pathname,
647 						&sub_elements[j],
648 						package->ret_info2.object_type[j], j);
649 					if (ACPI_FAILURE(status)) {
650 						return (status);
651 					}
652 				}
653 				break;
654 
655 			case ACPI_PTYPE2_MIN:
656 
657 				/* Each sub-package has a variable but minimum length */
658 
659 				expected_count = package->ret_info.count1;
660 				if (sub_package->package.count < expected_count) {
661 					count = sub_package->package.count;
662 					goto package_too_small;
663 				}
664 
665 				/* Check the type of each sub-package element */
666 
667 				status =
668 				    acpi_ns_check_package_elements(pathname,
669 								   sub_elements,
670 								   package->
671 								   ret_info.
672 								   object_type1,
673 								   sub_package->
674 								   package.
675 								   count, 0, 0,
676 								   0);
677 				if (ACPI_FAILURE(status)) {
678 					return (status);
679 				}
680 				break;
681 
682 			case ACPI_PTYPE2_COUNT:
683 
684 				/* First element is the (Integer) count of elements to follow */
685 
686 				status =
687 				    acpi_ns_check_object_type(pathname,
688 							      sub_elements,
689 							      ACPI_RTYPE_INTEGER,
690 							      0);
691 				if (ACPI_FAILURE(status)) {
692 					return (status);
693 				}
694 
695 				/* Make sure package is large enough for the Count */
696 
697 				expected_count =
698 				    (u32) (*sub_elements)->integer.value;
699 				if (sub_package->package.count < expected_count) {
700 					count = sub_package->package.count;
701 					goto package_too_small;
702 				}
703 
704 				/* Check the type of each sub-package element */
705 
706 				status =
707 				    acpi_ns_check_package_elements(pathname,
708 								   (sub_elements
709 								    + 1),
710 								   package->
711 								   ret_info.
712 								   object_type1,
713 								   (expected_count
714 								    - 1), 0, 0,
715 								   1);
716 				if (ACPI_FAILURE(status)) {
717 					return (status);
718 				}
719 				break;
720 
721 			default:
722 				break;
723 			}
724 
725 			elements++;
726 		}
727 		break;
728 
729 	default:
730 
731 		/* Should not get here if predefined info table is correct */
732 
733 		ACPI_WARNING((AE_INFO,
734 			      "%s: Invalid internal return type in table entry: %X",
735 			      pathname, package->ret_info.type));
736 
737 		return (AE_AML_INTERNAL);
738 	}
739 
740 	return (AE_OK);
741 
742       package_too_small:
743 
744 	/* Error exit for the case with an incorrect package count */
745 
746 	ACPI_WARNING((AE_INFO, "%s: Return Package is too small - "
747 		      "found %u, expected %u", pathname, count,
748 		      expected_count));
749 
750 	return (AE_AML_OPERAND_VALUE);
751 }
752 
753 /*******************************************************************************
754  *
755  * FUNCTION:    acpi_ns_check_package_elements
756  *
757  * PARAMETERS:  Pathname        - Full pathname to the node (for error msgs)
758  *              Elements        - Pointer to the package elements array
759  *              Type1           - Object type for first group
760  *              Count1          - Count for first group
761  *              Type2           - Object type for second group
762  *              Count2          - Count for second group
763  *              start_index     - Start of the first group of elements
764  *
765  * RETURN:      Status
766  *
767  * DESCRIPTION: Check that all elements of a package are of the correct object
768  *              type. Supports up to two groups of different object types.
769  *
770  ******************************************************************************/
771 
772 static acpi_status
773 acpi_ns_check_package_elements(char *pathname,
774 			       union acpi_operand_object **elements,
775 			       u8 type1,
776 			       u32 count1,
777 			       u8 type2, u32 count2, u32 start_index)
778 {
779 	union acpi_operand_object **this_element = elements;
780 	acpi_status status;
781 	u32 i;
782 
783 	/*
784 	 * Up to two groups of package elements are supported by the data
785 	 * structure. All elements in each group must be of the same type.
786 	 * The second group can have a count of zero.
787 	 */
788 	for (i = 0; i < count1; i++) {
789 		status = acpi_ns_check_object_type(pathname, this_element,
790 						   type1, i + start_index);
791 		if (ACPI_FAILURE(status)) {
792 			return (status);
793 		}
794 		this_element++;
795 	}
796 
797 	for (i = 0; i < count2; i++) {
798 		status = acpi_ns_check_object_type(pathname, this_element,
799 						   type2,
800 						   (i + count1 + start_index));
801 		if (ACPI_FAILURE(status)) {
802 			return (status);
803 		}
804 		this_element++;
805 	}
806 
807 	return (AE_OK);
808 }
809 
810 /*******************************************************************************
811  *
812  * FUNCTION:    acpi_ns_check_object_type
813  *
814  * PARAMETERS:  Pathname        - Full pathname to the node (for error msgs)
815  *              return_object_ptr - Pointer to the object returned from the
816  *                                evaluation of a method or object
817  *              expected_btypes - Bitmap of expected return type(s)
818  *              package_index   - Index of object within parent package (if
819  *                                applicable - ACPI_NOT_PACKAGE otherwise)
820  *
821  * RETURN:      Status
822  *
823  * DESCRIPTION: Check the type of the return object against the expected object
824  *              type(s). Use of Btype allows multiple expected object types.
825  *
826  ******************************************************************************/
827 
828 static acpi_status
829 acpi_ns_check_object_type(char *pathname,
830 			  union acpi_operand_object **return_object_ptr,
831 			  u32 expected_btypes, u32 package_index)
832 {
833 	union acpi_operand_object *return_object = *return_object_ptr;
834 	acpi_status status = AE_OK;
835 	u32 return_btype;
836 	char type_buffer[48];	/* Room for 5 types */
837 	u32 this_rtype;
838 	u32 i;
839 	u32 j;
840 
841 	/*
842 	 * If we get a NULL return_object here, it is a NULL package element,
843 	 * and this is always an error.
844 	 */
845 	if (!return_object) {
846 		goto type_error_exit;
847 	}
848 
849 	/* A Namespace node should not get here, but make sure */
850 
851 	if (ACPI_GET_DESCRIPTOR_TYPE(return_object) == ACPI_DESC_TYPE_NAMED) {
852 		ACPI_WARNING((AE_INFO,
853 			      "%s: Invalid return type - Found a Namespace node [%4.4s] type %s",
854 			      pathname, return_object->node.name.ascii,
855 			      acpi_ut_get_type_name(return_object->node.type)));
856 		return (AE_AML_OPERAND_TYPE);
857 	}
858 
859 	/*
860 	 * Convert the object type (ACPI_TYPE_xxx) to a bitmapped object type.
861 	 * The bitmapped type allows multiple possible return types.
862 	 *
863 	 * Note, the cases below must handle all of the possible types returned
864 	 * from all of the predefined names (including elements of returned
865 	 * packages)
866 	 */
867 	switch (return_object->common.type) {
868 	case ACPI_TYPE_INTEGER:
869 		return_btype = ACPI_RTYPE_INTEGER;
870 		break;
871 
872 	case ACPI_TYPE_BUFFER:
873 		return_btype = ACPI_RTYPE_BUFFER;
874 		break;
875 
876 	case ACPI_TYPE_STRING:
877 		return_btype = ACPI_RTYPE_STRING;
878 		break;
879 
880 	case ACPI_TYPE_PACKAGE:
881 		return_btype = ACPI_RTYPE_PACKAGE;
882 		break;
883 
884 	case ACPI_TYPE_LOCAL_REFERENCE:
885 		return_btype = ACPI_RTYPE_REFERENCE;
886 		break;
887 
888 	default:
889 		/* Not one of the supported objects, must be incorrect */
890 
891 		goto type_error_exit;
892 	}
893 
894 	/* Is the object one of the expected types? */
895 
896 	if (!(return_btype & expected_btypes)) {
897 
898 		/* Type mismatch -- attempt repair of the returned object */
899 
900 		status = acpi_ns_repair_object(expected_btypes, package_index,
901 					       return_object_ptr);
902 		if (ACPI_SUCCESS(status)) {
903 			return (status);
904 		}
905 		goto type_error_exit;
906 	}
907 
908 	/* For reference objects, check that the reference type is correct */
909 
910 	if (return_object->common.type == ACPI_TYPE_LOCAL_REFERENCE) {
911 		status = acpi_ns_check_reference(pathname, return_object);
912 	}
913 
914 	return (status);
915 
916       type_error_exit:
917 
918 	/* Create a string with all expected types for this predefined object */
919 
920 	j = 1;
921 	type_buffer[0] = 0;
922 	this_rtype = ACPI_RTYPE_INTEGER;
923 
924 	for (i = 0; i < ACPI_NUM_RTYPES; i++) {
925 
926 		/* If one of the expected types, concatenate the name of this type */
927 
928 		if (expected_btypes & this_rtype) {
929 			ACPI_STRCAT(type_buffer, &acpi_rtype_names[i][j]);
930 			j = 0;	/* Use name separator from now on */
931 		}
932 		this_rtype <<= 1;	/* Next Rtype */
933 	}
934 
935 	if (package_index == ACPI_NOT_PACKAGE) {
936 		ACPI_WARNING((AE_INFO,
937 			      "%s: Return type mismatch - found %s, expected %s",
938 			      pathname,
939 			      acpi_ut_get_object_type_name(return_object),
940 			      type_buffer));
941 	} else {
942 		ACPI_WARNING((AE_INFO,
943 			      "%s: Return Package type mismatch at index %u - "
944 			      "found %s, expected %s", pathname, package_index,
945 			      acpi_ut_get_object_type_name(return_object),
946 			      type_buffer));
947 	}
948 
949 	return (AE_AML_OPERAND_TYPE);
950 }
951 
952 /*******************************************************************************
953  *
954  * FUNCTION:    acpi_ns_check_reference
955  *
956  * PARAMETERS:  Pathname        - Full pathname to the node (for error msgs)
957  *              return_object   - Object returned from the evaluation of a
958  *                                method or object
959  *
960  * RETURN:      Status
961  *
962  * DESCRIPTION: Check a returned reference object for the correct reference
963  *              type. The only reference type that can be returned from a
964  *              predefined method is a named reference. All others are invalid.
965  *
966  ******************************************************************************/
967 
968 static acpi_status
969 acpi_ns_check_reference(char *pathname,
970 			union acpi_operand_object *return_object)
971 {
972 
973 	/*
974 	 * Check the reference object for the correct reference type (opcode).
975 	 * The only type of reference that can be converted to an union acpi_object is
976 	 * a reference to a named object (reference class: NAME)
977 	 */
978 	if (return_object->reference.class == ACPI_REFCLASS_NAME) {
979 		return (AE_OK);
980 	}
981 
982 	ACPI_WARNING((AE_INFO,
983 		      "%s: Return type mismatch - "
984 		      "unexpected reference object type [%s] %2.2X",
985 		      pathname, acpi_ut_get_reference_name(return_object),
986 		      return_object->reference.class));
987 
988 	return (AE_AML_OPERAND_TYPE);
989 }
990 
991 /*******************************************************************************
992  *
993  * FUNCTION:    acpi_ns_repair_object
994  *
995  * PARAMETERS:  Pathname        - Full pathname to the node (for error msgs)
996  *              package_index   - Used to determine if target is in a package
997  *              return_object_ptr - Pointer to the object returned from the
998  *                                evaluation of a method or object
999  *
1000  * RETURN:      Status. AE_OK if repair was successful.
1001  *
1002  * DESCRIPTION: Attempt to repair/convert a return object of a type that was
1003  *              not expected.
1004  *
1005  ******************************************************************************/
1006 
1007 static acpi_status
1008 acpi_ns_repair_object(u32 expected_btypes,
1009 		      u32 package_index,
1010 		      union acpi_operand_object **return_object_ptr)
1011 {
1012 	union acpi_operand_object *return_object = *return_object_ptr;
1013 	union acpi_operand_object *new_object;
1014 	acpi_size length;
1015 
1016 	switch (return_object->common.type) {
1017 	case ACPI_TYPE_BUFFER:
1018 
1019 		if (!(expected_btypes & ACPI_RTYPE_STRING)) {
1020 			return (AE_AML_OPERAND_TYPE);
1021 		}
1022 
1023 		/*
1024 		 * Have a Buffer, expected a String, convert. Use a to_string
1025 		 * conversion, no transform performed on the buffer data. The best
1026 		 * example of this is the _BIF method, where the string data from
1027 		 * the battery is often (incorrectly) returned as buffer object(s).
1028 		 */
1029 		length = 0;
1030 		while ((length < return_object->buffer.length) &&
1031 		       (return_object->buffer.pointer[length])) {
1032 			length++;
1033 		}
1034 
1035 		/* Allocate a new string object */
1036 
1037 		new_object = acpi_ut_create_string_object(length);
1038 		if (!new_object) {
1039 			return (AE_NO_MEMORY);
1040 		}
1041 
1042 		/*
1043 		 * Copy the raw buffer data with no transform. String is already NULL
1044 		 * terminated at Length+1.
1045 		 */
1046 		ACPI_MEMCPY(new_object->string.pointer,
1047 			    return_object->buffer.pointer, length);
1048 
1049 		/* Install the new return object */
1050 
1051 		acpi_ut_remove_reference(return_object);
1052 		*return_object_ptr = new_object;
1053 
1054 		/*
1055 		 * If the object is a package element, we need to:
1056 		 * 1. Decrement the reference count of the orignal object, it was
1057 		 *    incremented when building the package
1058 		 * 2. Increment the reference count of the new object, it will be
1059 		 *    decremented when releasing the package
1060 		 */
1061 		if (package_index != ACPI_NOT_PACKAGE) {
1062 			acpi_ut_remove_reference(return_object);
1063 			acpi_ut_add_reference(new_object);
1064 		}
1065 		return (AE_OK);
1066 
1067 	default:
1068 		break;
1069 	}
1070 
1071 	return (AE_AML_OPERAND_TYPE);
1072 }
1073