xref: /openbmc/linux/drivers/acpi/acpica/nspredef.c (revision 7fe2f639)
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 - 2011, 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 #define ACPI_CREATE_PREDEFINED_TABLE
46 
47 #include <acpi/acpi.h>
48 #include "accommon.h"
49 #include "acnamesp.h"
50 #include "acpredef.h"
51 
52 #define _COMPONENT          ACPI_NAMESPACE
53 ACPI_MODULE_NAME("nspredef")
54 
55 /*******************************************************************************
56  *
57  * This module validates predefined ACPI objects that appear in the namespace,
58  * at the time they are evaluated (via acpi_evaluate_object). The purpose of this
59  * validation is to detect problems with BIOS-exposed predefined ACPI objects
60  * before the results are returned to the ACPI-related drivers.
61  *
62  * There are several areas that are validated:
63  *
64  *  1) The number of input arguments as defined by the method/object in the
65  *      ASL is validated against the ACPI specification.
66  *  2) The type of the return object (if any) is validated against the ACPI
67  *      specification.
68  *  3) For returned package objects, the count of package elements is
69  *      validated, as well as the type of each package element. Nested
70  *      packages are supported.
71  *
72  * For any problems found, a warning message is issued.
73  *
74  ******************************************************************************/
75 /* Local prototypes */
76 static acpi_status
77 acpi_ns_check_package(struct acpi_predefined_data *data,
78 		      union acpi_operand_object **return_object_ptr);
79 
80 static acpi_status
81 acpi_ns_check_package_list(struct acpi_predefined_data *data,
82 			   const union acpi_predefined_info *package,
83 			   union acpi_operand_object **elements, u32 count);
84 
85 static acpi_status
86 acpi_ns_check_package_elements(struct acpi_predefined_data *data,
87 			       union acpi_operand_object **elements,
88 			       u8 type1,
89 			       u32 count1,
90 			       u8 type2, u32 count2, u32 start_index);
91 
92 static acpi_status
93 acpi_ns_check_object_type(struct acpi_predefined_data *data,
94 			  union acpi_operand_object **return_object_ptr,
95 			  u32 expected_btypes, u32 package_index);
96 
97 static acpi_status
98 acpi_ns_check_reference(struct acpi_predefined_data *data,
99 			union acpi_operand_object *return_object);
100 
101 static void acpi_ns_get_expected_types(char *buffer, u32 expected_btypes);
102 
103 /*
104  * Names for the types that can be returned by the predefined objects.
105  * Used for warning messages. Must be in the same order as the ACPI_RTYPEs
106  */
107 static const char *acpi_rtype_names[] = {
108 	"/Integer",
109 	"/String",
110 	"/Buffer",
111 	"/Package",
112 	"/Reference",
113 };
114 
115 /*******************************************************************************
116  *
117  * FUNCTION:    acpi_ns_check_predefined_names
118  *
119  * PARAMETERS:  Node            - Namespace node for the method/object
120  *              user_param_count - Number of parameters actually passed
121  *              return_status   - Status from the object evaluation
122  *              return_object_ptr - Pointer to the object returned from the
123  *                                evaluation of a method or object
124  *
125  * RETURN:      Status
126  *
127  * DESCRIPTION: Check an ACPI name for a match in the predefined name list.
128  *
129  ******************************************************************************/
130 
131 acpi_status
132 acpi_ns_check_predefined_names(struct acpi_namespace_node *node,
133 			       u32 user_param_count,
134 			       acpi_status return_status,
135 			       union acpi_operand_object **return_object_ptr)
136 {
137 	union acpi_operand_object *return_object = *return_object_ptr;
138 	acpi_status status = AE_OK;
139 	const union acpi_predefined_info *predefined;
140 	char *pathname;
141 	struct acpi_predefined_data *data;
142 
143 	/* Match the name for this method/object against the predefined list */
144 
145 	predefined = acpi_ns_check_for_predefined_name(node);
146 
147 	/* Get the full pathname to the object, for use in warning messages */
148 
149 	pathname = acpi_ns_get_external_pathname(node);
150 	if (!pathname) {
151 		return AE_OK;	/* Could not get pathname, ignore */
152 	}
153 
154 	/*
155 	 * Check that the parameter count for this method matches the ASL
156 	 * definition. For predefined names, ensure that both the caller and
157 	 * the method itself are in accordance with the ACPI specification.
158 	 */
159 	acpi_ns_check_parameter_count(pathname, node, user_param_count,
160 				      predefined);
161 
162 	/* If not a predefined name, we cannot validate the return object */
163 
164 	if (!predefined) {
165 		goto cleanup;
166 	}
167 
168 	/*
169 	 * If the method failed or did not actually return an object, we cannot
170 	 * validate the return object
171 	 */
172 	if ((return_status != AE_OK) && (return_status != AE_CTRL_RETURN_VALUE)) {
173 		goto cleanup;
174 	}
175 
176 	/*
177 	 * If there is no return value, check if we require a return value for
178 	 * this predefined name. Either one return value is expected, or none,
179 	 * for both methods and other objects.
180 	 *
181 	 * Exit now if there is no return object. Warning if one was expected.
182 	 */
183 	if (!return_object) {
184 		if ((predefined->info.expected_btypes) &&
185 		    (!(predefined->info.expected_btypes & ACPI_RTYPE_NONE))) {
186 			ACPI_WARN_PREDEFINED((AE_INFO, pathname,
187 					      ACPI_WARN_ALWAYS,
188 					      "Missing expected return value"));
189 
190 			status = AE_AML_NO_RETURN_VALUE;
191 		}
192 		goto cleanup;
193 	}
194 
195 	/*
196 	 * 1) We have a return value, but if one wasn't expected, just exit, this is
197 	 * not a problem. For example, if the "Implicit Return" feature is
198 	 * enabled, methods will always return a value.
199 	 *
200 	 * 2) If the return value can be of any type, then we cannot perform any
201 	 * validation, exit.
202 	 */
203 	if ((!predefined->info.expected_btypes) ||
204 	    (predefined->info.expected_btypes == ACPI_RTYPE_ALL)) {
205 		goto cleanup;
206 	}
207 
208 	/* Create the parameter data block for object validation */
209 
210 	data = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_predefined_data));
211 	if (!data) {
212 		goto cleanup;
213 	}
214 	data->predefined = predefined;
215 	data->node_flags = node->flags;
216 	data->pathname = pathname;
217 
218 	/*
219 	 * Check that the type of the main return object is what is expected
220 	 * for this predefined name
221 	 */
222 	status = acpi_ns_check_object_type(data, return_object_ptr,
223 					   predefined->info.expected_btypes,
224 					   ACPI_NOT_PACKAGE_ELEMENT);
225 	if (ACPI_FAILURE(status)) {
226 		goto exit;
227 	}
228 
229 	/*
230 	 * For returned Package objects, check the type of all sub-objects.
231 	 * Note: Package may have been newly created by call above.
232 	 */
233 	if ((*return_object_ptr)->common.type == ACPI_TYPE_PACKAGE) {
234 		data->parent_package = *return_object_ptr;
235 		status = acpi_ns_check_package(data, return_object_ptr);
236 		if (ACPI_FAILURE(status)) {
237 			goto exit;
238 		}
239 	}
240 
241 	/*
242 	 * The return object was OK, or it was successfully repaired above.
243 	 * Now make some additional checks such as verifying that package
244 	 * objects are sorted correctly (if required) or buffer objects have
245 	 * the correct data width (bytes vs. dwords). These repairs are
246 	 * performed on a per-name basis, i.e., the code is specific to
247 	 * particular predefined names.
248 	 */
249 	status = acpi_ns_complex_repairs(data, node, status, return_object_ptr);
250 
251 exit:
252 	/*
253 	 * If the object validation failed or if we successfully repaired one
254 	 * or more objects, mark the parent node to suppress further warning
255 	 * messages during the next evaluation of the same method/object.
256 	 */
257 	if (ACPI_FAILURE(status) || (data->flags & ACPI_OBJECT_REPAIRED)) {
258 		node->flags |= ANOBJ_EVALUATED;
259 	}
260 	ACPI_FREE(data);
261 
262 cleanup:
263 	ACPI_FREE(pathname);
264 	return (status);
265 }
266 
267 /*******************************************************************************
268  *
269  * FUNCTION:    acpi_ns_check_parameter_count
270  *
271  * PARAMETERS:  Pathname        - Full pathname to the node (for error msgs)
272  *              Node            - Namespace node for the method/object
273  *              user_param_count - Number of args passed in by the caller
274  *              Predefined      - Pointer to entry in predefined name table
275  *
276  * RETURN:      None
277  *
278  * DESCRIPTION: Check that the declared (in ASL/AML) parameter count for a
279  *              predefined name is what is expected (i.e., what is defined in
280  *              the ACPI specification for this predefined name.)
281  *
282  ******************************************************************************/
283 
284 void
285 acpi_ns_check_parameter_count(char *pathname,
286 			      struct acpi_namespace_node *node,
287 			      u32 user_param_count,
288 			      const union acpi_predefined_info *predefined)
289 {
290 	u32 param_count;
291 	u32 required_params_current;
292 	u32 required_params_old;
293 
294 	/* Methods have 0-7 parameters. All other types have zero. */
295 
296 	param_count = 0;
297 	if (node->type == ACPI_TYPE_METHOD) {
298 		param_count = node->object->method.param_count;
299 	}
300 
301 	if (!predefined) {
302 		/*
303 		 * Check the parameter count for non-predefined methods/objects.
304 		 *
305 		 * Warning if too few or too many arguments have been passed by the
306 		 * caller. An incorrect number of arguments may not cause the method
307 		 * to fail. However, the method will fail if there are too few
308 		 * arguments and the method attempts to use one of the missing ones.
309 		 */
310 		if (user_param_count < param_count) {
311 			ACPI_WARN_PREDEFINED((AE_INFO, pathname,
312 					      ACPI_WARN_ALWAYS,
313 					      "Insufficient arguments - needs %u, found %u",
314 					      param_count, user_param_count));
315 		} else if (user_param_count > param_count) {
316 			ACPI_WARN_PREDEFINED((AE_INFO, pathname,
317 					      ACPI_WARN_ALWAYS,
318 					      "Excess arguments - needs %u, found %u",
319 					      param_count, user_param_count));
320 		}
321 		return;
322 	}
323 
324 	/*
325 	 * Validate the user-supplied parameter count.
326 	 * Allow two different legal argument counts (_SCP, etc.)
327 	 */
328 	required_params_current = predefined->info.param_count & 0x0F;
329 	required_params_old = predefined->info.param_count >> 4;
330 
331 	if (user_param_count != ACPI_UINT32_MAX) {
332 		if ((user_param_count != required_params_current) &&
333 		    (user_param_count != required_params_old)) {
334 			ACPI_WARN_PREDEFINED((AE_INFO, pathname,
335 					      ACPI_WARN_ALWAYS,
336 					      "Parameter count mismatch - "
337 					      "caller passed %u, ACPI requires %u",
338 					      user_param_count,
339 					      required_params_current));
340 		}
341 	}
342 
343 	/*
344 	 * Check that the ASL-defined parameter count is what is expected for
345 	 * this predefined name (parameter count as defined by the ACPI
346 	 * specification)
347 	 */
348 	if ((param_count != required_params_current) &&
349 	    (param_count != required_params_old)) {
350 		ACPI_WARN_PREDEFINED((AE_INFO, pathname, node->flags,
351 				      "Parameter count mismatch - ASL declared %u, ACPI requires %u",
352 				      param_count, required_params_current));
353 	}
354 }
355 
356 /*******************************************************************************
357  *
358  * FUNCTION:    acpi_ns_check_for_predefined_name
359  *
360  * PARAMETERS:  Node            - Namespace node for the method/object
361  *
362  * RETURN:      Pointer to entry in predefined table. NULL indicates not found.
363  *
364  * DESCRIPTION: Check an object name against the predefined object list.
365  *
366  ******************************************************************************/
367 
368 const union acpi_predefined_info *acpi_ns_check_for_predefined_name(struct
369 								    acpi_namespace_node
370 								    *node)
371 {
372 	const union acpi_predefined_info *this_name;
373 
374 	/* Quick check for a predefined name, first character must be underscore */
375 
376 	if (node->name.ascii[0] != '_') {
377 		return (NULL);
378 	}
379 
380 	/* Search info table for a predefined method/object name */
381 
382 	this_name = predefined_names;
383 	while (this_name->info.name[0]) {
384 		if (ACPI_COMPARE_NAME(node->name.ascii, this_name->info.name)) {
385 			return (this_name);
386 		}
387 
388 		/*
389 		 * Skip next entry in the table if this name returns a Package
390 		 * (next entry contains the package info)
391 		 */
392 		if (this_name->info.expected_btypes & ACPI_RTYPE_PACKAGE) {
393 			this_name++;
394 		}
395 
396 		this_name++;
397 	}
398 
399 	return (NULL);		/* Not found */
400 }
401 
402 /*******************************************************************************
403  *
404  * FUNCTION:    acpi_ns_check_package
405  *
406  * PARAMETERS:  Data            - Pointer to validation data structure
407  *              return_object_ptr - Pointer to the object returned from the
408  *                                evaluation of a method or object
409  *
410  * RETURN:      Status
411  *
412  * DESCRIPTION: Check a returned package object for the correct count and
413  *              correct type of all sub-objects.
414  *
415  ******************************************************************************/
416 
417 static acpi_status
418 acpi_ns_check_package(struct acpi_predefined_data *data,
419 		      union acpi_operand_object **return_object_ptr)
420 {
421 	union acpi_operand_object *return_object = *return_object_ptr;
422 	const union acpi_predefined_info *package;
423 	union acpi_operand_object **elements;
424 	acpi_status status = AE_OK;
425 	u32 expected_count;
426 	u32 count;
427 	u32 i;
428 
429 	ACPI_FUNCTION_NAME(ns_check_package);
430 
431 	/* The package info for this name is in the next table entry */
432 
433 	package = data->predefined + 1;
434 
435 	ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
436 			  "%s Validating return Package of Type %X, Count %X\n",
437 			  data->pathname, package->ret_info.type,
438 			  return_object->package.count));
439 
440 	/*
441 	 * For variable-length Packages, we can safely remove all embedded
442 	 * and trailing NULL package elements
443 	 */
444 	acpi_ns_remove_null_elements(data, package->ret_info.type,
445 				     return_object);
446 
447 	/* Extract package count and elements array */
448 
449 	elements = return_object->package.elements;
450 	count = return_object->package.count;
451 
452 	/* The package must have at least one element, else invalid */
453 
454 	if (!count) {
455 		ACPI_WARN_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
456 				      "Return Package has no elements (empty)"));
457 
458 		return (AE_AML_OPERAND_VALUE);
459 	}
460 
461 	/*
462 	 * Decode the type of the expected package contents
463 	 *
464 	 * PTYPE1 packages contain no subpackages
465 	 * PTYPE2 packages contain sub-packages
466 	 */
467 	switch (package->ret_info.type) {
468 	case ACPI_PTYPE1_FIXED:
469 
470 		/*
471 		 * The package count is fixed and there are no sub-packages
472 		 *
473 		 * If package is too small, exit.
474 		 * If package is larger than expected, issue warning but continue
475 		 */
476 		expected_count =
477 		    package->ret_info.count1 + package->ret_info.count2;
478 		if (count < expected_count) {
479 			goto package_too_small;
480 		} else if (count > expected_count) {
481 			ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
482 					  "%s: Return Package is larger than needed - "
483 					  "found %u, expected %u\n",
484 					  data->pathname, count,
485 					  expected_count));
486 		}
487 
488 		/* Validate all elements of the returned package */
489 
490 		status = acpi_ns_check_package_elements(data, elements,
491 							package->ret_info.
492 							object_type1,
493 							package->ret_info.
494 							count1,
495 							package->ret_info.
496 							object_type2,
497 							package->ret_info.
498 							count2, 0);
499 		break;
500 
501 	case ACPI_PTYPE1_VAR:
502 
503 		/*
504 		 * The package count is variable, there are no sub-packages, and all
505 		 * elements must be of the same type
506 		 */
507 		for (i = 0; i < count; i++) {
508 			status = acpi_ns_check_object_type(data, elements,
509 							   package->ret_info.
510 							   object_type1, i);
511 			if (ACPI_FAILURE(status)) {
512 				return (status);
513 			}
514 			elements++;
515 		}
516 		break;
517 
518 	case ACPI_PTYPE1_OPTION:
519 
520 		/*
521 		 * The package count is variable, there are no sub-packages. There are
522 		 * a fixed number of required elements, and a variable number of
523 		 * optional elements.
524 		 *
525 		 * Check if package is at least as large as the minimum required
526 		 */
527 		expected_count = package->ret_info3.count;
528 		if (count < expected_count) {
529 			goto package_too_small;
530 		}
531 
532 		/* Variable number of sub-objects */
533 
534 		for (i = 0; i < count; i++) {
535 			if (i < package->ret_info3.count) {
536 
537 				/* These are the required package elements (0, 1, or 2) */
538 
539 				status =
540 				    acpi_ns_check_object_type(data, elements,
541 							      package->
542 							      ret_info3.
543 							      object_type[i],
544 							      i);
545 				if (ACPI_FAILURE(status)) {
546 					return (status);
547 				}
548 			} else {
549 				/* These are the optional package elements */
550 
551 				status =
552 				    acpi_ns_check_object_type(data, elements,
553 							      package->
554 							      ret_info3.
555 							      tail_object_type,
556 							      i);
557 				if (ACPI_FAILURE(status)) {
558 					return (status);
559 				}
560 			}
561 			elements++;
562 		}
563 		break;
564 
565 	case ACPI_PTYPE2_REV_FIXED:
566 
567 		/* First element is the (Integer) revision */
568 
569 		status = acpi_ns_check_object_type(data, elements,
570 						   ACPI_RTYPE_INTEGER, 0);
571 		if (ACPI_FAILURE(status)) {
572 			return (status);
573 		}
574 
575 		elements++;
576 		count--;
577 
578 		/* Examine the sub-packages */
579 
580 		status =
581 		    acpi_ns_check_package_list(data, package, elements, count);
582 		break;
583 
584 	case ACPI_PTYPE2_PKG_COUNT:
585 
586 		/* First element is the (Integer) count of sub-packages to follow */
587 
588 		status = acpi_ns_check_object_type(data, elements,
589 						   ACPI_RTYPE_INTEGER, 0);
590 		if (ACPI_FAILURE(status)) {
591 			return (status);
592 		}
593 
594 		/*
595 		 * Count cannot be larger than the parent package length, but allow it
596 		 * to be smaller. The >= accounts for the Integer above.
597 		 */
598 		expected_count = (u32) (*elements)->integer.value;
599 		if (expected_count >= count) {
600 			goto package_too_small;
601 		}
602 
603 		count = expected_count;
604 		elements++;
605 
606 		/* Examine the sub-packages */
607 
608 		status =
609 		    acpi_ns_check_package_list(data, package, elements, count);
610 		break;
611 
612 	case ACPI_PTYPE2:
613 	case ACPI_PTYPE2_FIXED:
614 	case ACPI_PTYPE2_MIN:
615 	case ACPI_PTYPE2_COUNT:
616 
617 		/*
618 		 * These types all return a single Package that consists of a
619 		 * variable number of sub-Packages.
620 		 *
621 		 * First, ensure that the first element is a sub-Package. If not,
622 		 * the BIOS may have incorrectly returned the object as a single
623 		 * package instead of a Package of Packages (a common error if
624 		 * there is only one entry). We may be able to repair this by
625 		 * wrapping the returned Package with a new outer Package.
626 		 */
627 		if (*elements
628 		    && ((*elements)->common.type != ACPI_TYPE_PACKAGE)) {
629 
630 			/* Create the new outer package and populate it */
631 
632 			status =
633 			    acpi_ns_repair_package_list(data,
634 							return_object_ptr);
635 			if (ACPI_FAILURE(status)) {
636 				return (status);
637 			}
638 
639 			/* Update locals to point to the new package (of 1 element) */
640 
641 			return_object = *return_object_ptr;
642 			elements = return_object->package.elements;
643 			count = 1;
644 		}
645 
646 		/* Examine the sub-packages */
647 
648 		status =
649 		    acpi_ns_check_package_list(data, package, elements, count);
650 		break;
651 
652 	default:
653 
654 		/* Should not get here if predefined info table is correct */
655 
656 		ACPI_WARN_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
657 				      "Invalid internal return type in table entry: %X",
658 				      package->ret_info.type));
659 
660 		return (AE_AML_INTERNAL);
661 	}
662 
663 	return (status);
664 
665 package_too_small:
666 
667 	/* Error exit for the case with an incorrect package count */
668 
669 	ACPI_WARN_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
670 			      "Return Package is too small - found %u elements, expected %u",
671 			      count, expected_count));
672 
673 	return (AE_AML_OPERAND_VALUE);
674 }
675 
676 /*******************************************************************************
677  *
678  * FUNCTION:    acpi_ns_check_package_list
679  *
680  * PARAMETERS:  Data            - Pointer to validation data structure
681  *              Package         - Pointer to package-specific info for method
682  *              Elements        - Element list of parent package. All elements
683  *                                of this list should be of type Package.
684  *              Count           - Count of subpackages
685  *
686  * RETURN:      Status
687  *
688  * DESCRIPTION: Examine a list of subpackages
689  *
690  ******************************************************************************/
691 
692 static acpi_status
693 acpi_ns_check_package_list(struct acpi_predefined_data *data,
694 			   const union acpi_predefined_info *package,
695 			   union acpi_operand_object **elements, u32 count)
696 {
697 	union acpi_operand_object *sub_package;
698 	union acpi_operand_object **sub_elements;
699 	acpi_status status;
700 	u32 expected_count;
701 	u32 i;
702 	u32 j;
703 
704 	/*
705 	 * Validate each sub-Package in the parent Package
706 	 *
707 	 * NOTE: assumes list of sub-packages contains no NULL elements.
708 	 * Any NULL elements should have been removed by earlier call
709 	 * to acpi_ns_remove_null_elements.
710 	 */
711 	for (i = 0; i < count; i++) {
712 		sub_package = *elements;
713 		sub_elements = sub_package->package.elements;
714 		data->parent_package = sub_package;
715 
716 		/* Each sub-object must be of type Package */
717 
718 		status = acpi_ns_check_object_type(data, &sub_package,
719 						   ACPI_RTYPE_PACKAGE, i);
720 		if (ACPI_FAILURE(status)) {
721 			return (status);
722 		}
723 
724 		/* Examine the different types of expected sub-packages */
725 
726 		data->parent_package = sub_package;
727 		switch (package->ret_info.type) {
728 		case ACPI_PTYPE2:
729 		case ACPI_PTYPE2_PKG_COUNT:
730 		case ACPI_PTYPE2_REV_FIXED:
731 
732 			/* Each subpackage has a fixed number of elements */
733 
734 			expected_count =
735 			    package->ret_info.count1 + package->ret_info.count2;
736 			if (sub_package->package.count < expected_count) {
737 				goto package_too_small;
738 			}
739 
740 			status =
741 			    acpi_ns_check_package_elements(data, sub_elements,
742 							   package->ret_info.
743 							   object_type1,
744 							   package->ret_info.
745 							   count1,
746 							   package->ret_info.
747 							   object_type2,
748 							   package->ret_info.
749 							   count2, 0);
750 			if (ACPI_FAILURE(status)) {
751 				return (status);
752 			}
753 			break;
754 
755 		case ACPI_PTYPE2_FIXED:
756 
757 			/* Each sub-package has a fixed length */
758 
759 			expected_count = package->ret_info2.count;
760 			if (sub_package->package.count < expected_count) {
761 				goto package_too_small;
762 			}
763 
764 			/* Check the type of each sub-package element */
765 
766 			for (j = 0; j < expected_count; j++) {
767 				status =
768 				    acpi_ns_check_object_type(data,
769 							      &sub_elements[j],
770 							      package->
771 							      ret_info2.
772 							      object_type[j],
773 							      j);
774 				if (ACPI_FAILURE(status)) {
775 					return (status);
776 				}
777 			}
778 			break;
779 
780 		case ACPI_PTYPE2_MIN:
781 
782 			/* Each sub-package has a variable but minimum length */
783 
784 			expected_count = package->ret_info.count1;
785 			if (sub_package->package.count < expected_count) {
786 				goto package_too_small;
787 			}
788 
789 			/* Check the type of each sub-package element */
790 
791 			status =
792 			    acpi_ns_check_package_elements(data, sub_elements,
793 							   package->ret_info.
794 							   object_type1,
795 							   sub_package->package.
796 							   count, 0, 0, 0);
797 			if (ACPI_FAILURE(status)) {
798 				return (status);
799 			}
800 			break;
801 
802 		case ACPI_PTYPE2_COUNT:
803 
804 			/*
805 			 * First element is the (Integer) count of elements, including
806 			 * the count field (the ACPI name is num_elements)
807 			 */
808 			status = acpi_ns_check_object_type(data, sub_elements,
809 							   ACPI_RTYPE_INTEGER,
810 							   0);
811 			if (ACPI_FAILURE(status)) {
812 				return (status);
813 			}
814 
815 			/*
816 			 * Make sure package is large enough for the Count and is
817 			 * is as large as the minimum size
818 			 */
819 			expected_count = (u32)(*sub_elements)->integer.value;
820 			if (sub_package->package.count < expected_count) {
821 				goto package_too_small;
822 			}
823 			if (sub_package->package.count <
824 			    package->ret_info.count1) {
825 				expected_count = package->ret_info.count1;
826 				goto package_too_small;
827 			}
828 			if (expected_count == 0) {
829 				/*
830 				 * Either the num_entries element was originally zero or it was
831 				 * a NULL element and repaired to an Integer of value zero.
832 				 * In either case, repair it by setting num_entries to be the
833 				 * actual size of the subpackage.
834 				 */
835 				expected_count = sub_package->package.count;
836 				(*sub_elements)->integer.value = expected_count;
837 			}
838 
839 			/* Check the type of each sub-package element */
840 
841 			status =
842 			    acpi_ns_check_package_elements(data,
843 							   (sub_elements + 1),
844 							   package->ret_info.
845 							   object_type1,
846 							   (expected_count - 1),
847 							   0, 0, 1);
848 			if (ACPI_FAILURE(status)) {
849 				return (status);
850 			}
851 			break;
852 
853 		default:	/* Should not get here, type was validated by caller */
854 
855 			return (AE_AML_INTERNAL);
856 		}
857 
858 		elements++;
859 	}
860 
861 	return (AE_OK);
862 
863 package_too_small:
864 
865 	/* The sub-package count was smaller than required */
866 
867 	ACPI_WARN_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
868 			      "Return Sub-Package[%u] is too small - found %u elements, expected %u",
869 			      i, sub_package->package.count, expected_count));
870 
871 	return (AE_AML_OPERAND_VALUE);
872 }
873 
874 /*******************************************************************************
875  *
876  * FUNCTION:    acpi_ns_check_package_elements
877  *
878  * PARAMETERS:  Data            - Pointer to validation data structure
879  *              Elements        - Pointer to the package elements array
880  *              Type1           - Object type for first group
881  *              Count1          - Count for first group
882  *              Type2           - Object type for second group
883  *              Count2          - Count for second group
884  *              start_index     - Start of the first group of elements
885  *
886  * RETURN:      Status
887  *
888  * DESCRIPTION: Check that all elements of a package are of the correct object
889  *              type. Supports up to two groups of different object types.
890  *
891  ******************************************************************************/
892 
893 static acpi_status
894 acpi_ns_check_package_elements(struct acpi_predefined_data *data,
895 			       union acpi_operand_object **elements,
896 			       u8 type1,
897 			       u32 count1,
898 			       u8 type2, u32 count2, u32 start_index)
899 {
900 	union acpi_operand_object **this_element = elements;
901 	acpi_status status;
902 	u32 i;
903 
904 	/*
905 	 * Up to two groups of package elements are supported by the data
906 	 * structure. All elements in each group must be of the same type.
907 	 * The second group can have a count of zero.
908 	 */
909 	for (i = 0; i < count1; i++) {
910 		status = acpi_ns_check_object_type(data, this_element,
911 						   type1, i + start_index);
912 		if (ACPI_FAILURE(status)) {
913 			return (status);
914 		}
915 		this_element++;
916 	}
917 
918 	for (i = 0; i < count2; i++) {
919 		status = acpi_ns_check_object_type(data, this_element,
920 						   type2,
921 						   (i + count1 + start_index));
922 		if (ACPI_FAILURE(status)) {
923 			return (status);
924 		}
925 		this_element++;
926 	}
927 
928 	return (AE_OK);
929 }
930 
931 /*******************************************************************************
932  *
933  * FUNCTION:    acpi_ns_check_object_type
934  *
935  * PARAMETERS:  Data            - Pointer to validation data structure
936  *              return_object_ptr - Pointer to the object returned from the
937  *                                evaluation of a method or object
938  *              expected_btypes - Bitmap of expected return type(s)
939  *              package_index   - Index of object within parent package (if
940  *                                applicable - ACPI_NOT_PACKAGE_ELEMENT
941  *                                otherwise)
942  *
943  * RETURN:      Status
944  *
945  * DESCRIPTION: Check the type of the return object against the expected object
946  *              type(s). Use of Btype allows multiple expected object types.
947  *
948  ******************************************************************************/
949 
950 static acpi_status
951 acpi_ns_check_object_type(struct acpi_predefined_data *data,
952 			  union acpi_operand_object **return_object_ptr,
953 			  u32 expected_btypes, u32 package_index)
954 {
955 	union acpi_operand_object *return_object = *return_object_ptr;
956 	acpi_status status = AE_OK;
957 	u32 return_btype;
958 	char type_buffer[48];	/* Room for 5 types */
959 
960 	/*
961 	 * If we get a NULL return_object here, it is a NULL package element.
962 	 * Since all extraneous NULL package elements were removed earlier by a
963 	 * call to acpi_ns_remove_null_elements, this is an unexpected NULL element.
964 	 * We will attempt to repair it.
965 	 */
966 	if (!return_object) {
967 		status = acpi_ns_repair_null_element(data, expected_btypes,
968 						     package_index,
969 						     return_object_ptr);
970 		if (ACPI_SUCCESS(status)) {
971 			return (AE_OK);	/* Repair was successful */
972 		}
973 		goto type_error_exit;
974 	}
975 
976 	/* A Namespace node should not get here, but make sure */
977 
978 	if (ACPI_GET_DESCRIPTOR_TYPE(return_object) == ACPI_DESC_TYPE_NAMED) {
979 		ACPI_WARN_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
980 				      "Invalid return type - Found a Namespace node [%4.4s] type %s",
981 				      return_object->node.name.ascii,
982 				      acpi_ut_get_type_name(return_object->node.
983 							    type)));
984 		return (AE_AML_OPERAND_TYPE);
985 	}
986 
987 	/*
988 	 * Convert the object type (ACPI_TYPE_xxx) to a bitmapped object type.
989 	 * The bitmapped type allows multiple possible return types.
990 	 *
991 	 * Note, the cases below must handle all of the possible types returned
992 	 * from all of the predefined names (including elements of returned
993 	 * packages)
994 	 */
995 	switch (return_object->common.type) {
996 	case ACPI_TYPE_INTEGER:
997 		return_btype = ACPI_RTYPE_INTEGER;
998 		break;
999 
1000 	case ACPI_TYPE_BUFFER:
1001 		return_btype = ACPI_RTYPE_BUFFER;
1002 		break;
1003 
1004 	case ACPI_TYPE_STRING:
1005 		return_btype = ACPI_RTYPE_STRING;
1006 		break;
1007 
1008 	case ACPI_TYPE_PACKAGE:
1009 		return_btype = ACPI_RTYPE_PACKAGE;
1010 		break;
1011 
1012 	case ACPI_TYPE_LOCAL_REFERENCE:
1013 		return_btype = ACPI_RTYPE_REFERENCE;
1014 		break;
1015 
1016 	default:
1017 		/* Not one of the supported objects, must be incorrect */
1018 
1019 		goto type_error_exit;
1020 	}
1021 
1022 	/* Is the object one of the expected types? */
1023 
1024 	if (return_btype & expected_btypes) {
1025 
1026 		/* For reference objects, check that the reference type is correct */
1027 
1028 		if (return_object->common.type == ACPI_TYPE_LOCAL_REFERENCE) {
1029 			status = acpi_ns_check_reference(data, return_object);
1030 		}
1031 
1032 		return (status);
1033 	}
1034 
1035 	/* Type mismatch -- attempt repair of the returned object */
1036 
1037 	status = acpi_ns_repair_object(data, expected_btypes,
1038 				       package_index, return_object_ptr);
1039 	if (ACPI_SUCCESS(status)) {
1040 		return (AE_OK);	/* Repair was successful */
1041 	}
1042 
1043       type_error_exit:
1044 
1045 	/* Create a string with all expected types for this predefined object */
1046 
1047 	acpi_ns_get_expected_types(type_buffer, expected_btypes);
1048 
1049 	if (package_index == ACPI_NOT_PACKAGE_ELEMENT) {
1050 		ACPI_WARN_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
1051 				      "Return type mismatch - found %s, expected %s",
1052 				      acpi_ut_get_object_type_name
1053 				      (return_object), type_buffer));
1054 	} else {
1055 		ACPI_WARN_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
1056 				      "Return Package type mismatch at index %u - "
1057 				      "found %s, expected %s", package_index,
1058 				      acpi_ut_get_object_type_name
1059 				      (return_object), type_buffer));
1060 	}
1061 
1062 	return (AE_AML_OPERAND_TYPE);
1063 }
1064 
1065 /*******************************************************************************
1066  *
1067  * FUNCTION:    acpi_ns_check_reference
1068  *
1069  * PARAMETERS:  Data            - Pointer to validation data structure
1070  *              return_object   - Object returned from the evaluation of a
1071  *                                method or object
1072  *
1073  * RETURN:      Status
1074  *
1075  * DESCRIPTION: Check a returned reference object for the correct reference
1076  *              type. The only reference type that can be returned from a
1077  *              predefined method is a named reference. All others are invalid.
1078  *
1079  ******************************************************************************/
1080 
1081 static acpi_status
1082 acpi_ns_check_reference(struct acpi_predefined_data *data,
1083 			union acpi_operand_object *return_object)
1084 {
1085 
1086 	/*
1087 	 * Check the reference object for the correct reference type (opcode).
1088 	 * The only type of reference that can be converted to an union acpi_object is
1089 	 * a reference to a named object (reference class: NAME)
1090 	 */
1091 	if (return_object->reference.class == ACPI_REFCLASS_NAME) {
1092 		return (AE_OK);
1093 	}
1094 
1095 	ACPI_WARN_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
1096 			      "Return type mismatch - unexpected reference object type [%s] %2.2X",
1097 			      acpi_ut_get_reference_name(return_object),
1098 			      return_object->reference.class));
1099 
1100 	return (AE_AML_OPERAND_TYPE);
1101 }
1102 
1103 /*******************************************************************************
1104  *
1105  * FUNCTION:    acpi_ns_get_expected_types
1106  *
1107  * PARAMETERS:  Buffer          - Pointer to where the string is returned
1108  *              expected_btypes - Bitmap of expected return type(s)
1109  *
1110  * RETURN:      Buffer is populated with type names.
1111  *
1112  * DESCRIPTION: Translate the expected types bitmap into a string of ascii
1113  *              names of expected types, for use in warning messages.
1114  *
1115  ******************************************************************************/
1116 
1117 static void acpi_ns_get_expected_types(char *buffer, u32 expected_btypes)
1118 {
1119 	u32 this_rtype;
1120 	u32 i;
1121 	u32 j;
1122 
1123 	j = 1;
1124 	buffer[0] = 0;
1125 	this_rtype = ACPI_RTYPE_INTEGER;
1126 
1127 	for (i = 0; i < ACPI_NUM_RTYPES; i++) {
1128 
1129 		/* If one of the expected types, concatenate the name of this type */
1130 
1131 		if (expected_btypes & this_rtype) {
1132 			ACPI_STRCAT(buffer, &acpi_rtype_names[i][j]);
1133 			j = 0;	/* Use name separator from now on */
1134 		}
1135 		this_rtype <<= 1;	/* Next Rtype */
1136 	}
1137 }
1138