1 /******************************************************************************
2  *
3  * Module Name: psargs - Parse AML opcode arguments
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2004, R. Byron Moore
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions, and the following disclaimer,
16  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43 
44 
45 #include <acpi/acpi.h>
46 #include <acpi/acparser.h>
47 #include <acpi/amlcode.h>
48 #include <acpi/acnamesp.h>
49 
50 #define _COMPONENT          ACPI_PARSER
51 	 ACPI_MODULE_NAME    ("psargs")
52 
53 
54 /*******************************************************************************
55  *
56  * FUNCTION:    acpi_ps_get_next_package_length
57  *
58  * PARAMETERS:  parser_state        - Current parser state object
59  *
60  * RETURN:      Decoded package length.  On completion, the AML pointer points
61  *              past the length byte or bytes.
62  *
63  * DESCRIPTION: Decode and return a package length field
64  *
65  ******************************************************************************/
66 
67 u32
acpi_ps_get_next_package_length(struct acpi_parse_state * parser_state)68 acpi_ps_get_next_package_length (
69 	struct acpi_parse_state         *parser_state)
70 {
71 	u32                             encoded_length;
72 	u32                             length = 0;
73 
74 
75 	ACPI_FUNCTION_TRACE ("ps_get_next_package_length");
76 
77 
78 	encoded_length = (u32) ACPI_GET8 (parser_state->aml);
79 	parser_state->aml++;
80 
81 
82 	switch (encoded_length >> 6) /* bits 6-7 contain encoding scheme */ {
83 	case 0: /* 1-byte encoding (bits 0-5) */
84 
85 		length = (encoded_length & 0x3F);
86 		break;
87 
88 
89 	case 1: /* 2-byte encoding (next byte + bits 0-3) */
90 
91 		length = ((ACPI_GET8 (parser_state->aml) << 04) |
92 				 (encoded_length & 0x0F));
93 		parser_state->aml++;
94 		break;
95 
96 
97 	case 2: /* 3-byte encoding (next 2 bytes + bits 0-3) */
98 
99 		length = ((ACPI_GET8 (parser_state->aml + 1) << 12) |
100 				  (ACPI_GET8 (parser_state->aml)    << 04) |
101 				  (encoded_length & 0x0F));
102 		parser_state->aml += 2;
103 		break;
104 
105 
106 	case 3: /* 4-byte encoding (next 3 bytes + bits 0-3) */
107 
108 		length = ((ACPI_GET8 (parser_state->aml + 2) << 20) |
109 				  (ACPI_GET8 (parser_state->aml + 1) << 12) |
110 				  (ACPI_GET8 (parser_state->aml)    << 04) |
111 				  (encoded_length & 0x0F));
112 		parser_state->aml += 3;
113 		break;
114 
115 	default:
116 
117 		/* Can't get here, only 2 bits / 4 cases */
118 		break;
119 	}
120 
121 	return_VALUE (length);
122 }
123 
124 
125 /*******************************************************************************
126  *
127  * FUNCTION:    acpi_ps_get_next_package_end
128  *
129  * PARAMETERS:  parser_state        - Current parser state object
130  *
131  * RETURN:      Pointer to end-of-package +1
132  *
133  * DESCRIPTION: Get next package length and return a pointer past the end of
134  *              the package.  Consumes the package length field
135  *
136  ******************************************************************************/
137 
138 u8 *
acpi_ps_get_next_package_end(struct acpi_parse_state * parser_state)139 acpi_ps_get_next_package_end (
140 	struct acpi_parse_state         *parser_state)
141 {
142 	u8                              *start = parser_state->aml;
143 	acpi_native_uint                length;
144 
145 
146 	ACPI_FUNCTION_TRACE ("ps_get_next_package_end");
147 
148 
149 	/* Function below changes parser_state->Aml */
150 
151 	length = (acpi_native_uint) acpi_ps_get_next_package_length (parser_state);
152 
153 	return_PTR (start + length); /* end of package */
154 }
155 
156 
157 /*******************************************************************************
158  *
159  * FUNCTION:    acpi_ps_get_next_namestring
160  *
161  * PARAMETERS:  parser_state        - Current parser state object
162  *
163  * RETURN:      Pointer to the start of the name string (pointer points into
164  *              the AML.
165  *
166  * DESCRIPTION: Get next raw namestring within the AML stream.  Handles all name
167  *              prefix characters.  Set parser state to point past the string.
168  *              (Name is consumed from the AML.)
169  *
170  ******************************************************************************/
171 
172 char *
acpi_ps_get_next_namestring(struct acpi_parse_state * parser_state)173 acpi_ps_get_next_namestring (
174 	struct acpi_parse_state         *parser_state)
175 {
176 	u8                              *start = parser_state->aml;
177 	u8                              *end = parser_state->aml;
178 
179 
180 	ACPI_FUNCTION_TRACE ("ps_get_next_namestring");
181 
182 
183 	/* Handle multiple prefix characters */
184 
185 	while (acpi_ps_is_prefix_char (ACPI_GET8 (end))) {
186 		/* Include prefix '\\' or '^' */
187 
188 		end++;
189 	}
190 
191 	/* Decode the path */
192 
193 	switch (ACPI_GET8 (end)) {
194 	case 0:
195 
196 		/* null_name */
197 
198 		if (end == start) {
199 			start = NULL;
200 		}
201 		end++;
202 		break;
203 
204 	case AML_DUAL_NAME_PREFIX:
205 
206 		/* Two name segments */
207 
208 		end += 1 + (2 * ACPI_NAME_SIZE);
209 		break;
210 
211 	case AML_MULTI_NAME_PREFIX_OP:
212 
213 		/* Multiple name segments, 4 chars each */
214 
215 		end += 2 + ((acpi_size) ACPI_GET8 (end + 1) * ACPI_NAME_SIZE);
216 		break;
217 
218 	default:
219 
220 		/* Single name segment */
221 
222 		end += ACPI_NAME_SIZE;
223 		break;
224 	}
225 
226 	parser_state->aml = (u8*) end;
227 	return_PTR ((char *) start);
228 }
229 
230 
231 /*******************************************************************************
232  *
233  * FUNCTION:    acpi_ps_get_next_namepath
234  *
235  * PARAMETERS:  parser_state        - Current parser state object
236  *              Arg                 - Where the namepath will be stored
237  *              arg_count           - If the namepath points to a control method
238  *                                    the method's argument is returned here.
239  *              method_call         - Whether the namepath can possibly be the
240  *                                    start of a method call
241  *
242  * RETURN:      Status
243  *
244  * DESCRIPTION: Get next name (if method call, return # of required args).
245  *              Names are looked up in the internal namespace to determine
246  *              if the name represents a control method.  If a method
247  *              is found, the number of arguments to the method is returned.
248  *              This information is critical for parsing to continue correctly.
249  *
250  ******************************************************************************/
251 
252 acpi_status
acpi_ps_get_next_namepath(struct acpi_walk_state * walk_state,struct acpi_parse_state * parser_state,union acpi_parse_object * arg,u8 method_call)253 acpi_ps_get_next_namepath (
254 	struct acpi_walk_state          *walk_state,
255 	struct acpi_parse_state         *parser_state,
256 	union acpi_parse_object         *arg,
257 	u8                              method_call)
258 {
259 	char                            *path;
260 	union acpi_parse_object         *name_op;
261 	acpi_status                     status = AE_OK;
262 	union acpi_operand_object       *method_desc;
263 	struct acpi_namespace_node      *node;
264 	union acpi_generic_state        scope_info;
265 
266 
267 	ACPI_FUNCTION_TRACE ("ps_get_next_namepath");
268 
269 
270 	path = acpi_ps_get_next_namestring (parser_state);
271 
272 	/* Null path case is allowed */
273 
274 	if (path) {
275 		/*
276 		 * Lookup the name in the internal namespace
277 		 */
278 		scope_info.scope.node = NULL;
279 		node = parser_state->start_node;
280 		if (node) {
281 			scope_info.scope.node = node;
282 		}
283 
284 		/*
285 		 * Lookup object.  We don't want to add anything new to the namespace
286 		 * here, however.  So we use MODE_EXECUTE.  Allow searching of the
287 		 * parent tree, but don't open a new scope -- we just want to lookup the
288 		 * object  (MUST BE mode EXECUTE to perform upsearch)
289 		 */
290 		status = acpi_ns_lookup (&scope_info, path, ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,
291 				 ACPI_NS_SEARCH_PARENT | ACPI_NS_DONT_OPEN_SCOPE, NULL, &node);
292 		if (ACPI_SUCCESS (status) && method_call) {
293 			if (node->type == ACPI_TYPE_METHOD) {
294 				/*
295 				 * This name is actually a control method invocation
296 				 */
297 				method_desc = acpi_ns_get_attached_object (node);
298 				ACPI_DEBUG_PRINT ((ACPI_DB_PARSE,
299 					"Control Method - %p Desc %p Path=%p\n",
300 					node, method_desc, path));
301 
302 				name_op = acpi_ps_alloc_op (AML_INT_NAMEPATH_OP);
303 				if (!name_op) {
304 					return_ACPI_STATUS (AE_NO_MEMORY);
305 				}
306 
307 				/* Change arg into a METHOD CALL and attach name to it */
308 
309 				acpi_ps_init_op (arg, AML_INT_METHODCALL_OP);
310 				name_op->common.value.name = path;
311 
312 				/* Point METHODCALL/NAME to the METHOD Node */
313 
314 				name_op->common.node = node;
315 				acpi_ps_append_arg (arg, name_op);
316 
317 				if (!method_desc) {
318 					ACPI_REPORT_ERROR ((
319 						"ps_get_next_namepath: Control Method %p has no attached object\n",
320 						node));
321 					return_ACPI_STATUS (AE_AML_INTERNAL);
322 				}
323 
324 				ACPI_DEBUG_PRINT ((ACPI_DB_PARSE,
325 					"Control Method - %p Args %X\n",
326 					node, method_desc->method.param_count));
327 
328 				/* Get the number of arguments to expect */
329 
330 				walk_state->arg_count = method_desc->method.param_count;
331 				return_ACPI_STATUS (AE_OK);
332 			}
333 
334 			/*
335 			 * Else this is normal named object reference.
336 			 * Just init the NAMEPATH object with the pathname.
337 			 * (See code below)
338 			 */
339 		}
340 
341 		if (ACPI_FAILURE (status)) {
342 			/*
343 			 * 1) Any error other than NOT_FOUND is always severe
344 			 * 2) NOT_FOUND is only important if we are executing a method.
345 			 * 3) If executing a cond_ref_of opcode, NOT_FOUND is ok.
346 			 */
347 			if ((((walk_state->parse_flags & ACPI_PARSE_MODE_MASK) == ACPI_PARSE_EXECUTE) &&
348 				(status == AE_NOT_FOUND)                                                &&
349 				(walk_state->op->common.aml_opcode != AML_COND_REF_OF_OP)) ||
350 
351 				(status != AE_NOT_FOUND)) {
352 				ACPI_REPORT_NSERROR (path, status);
353 
354 				acpi_os_printf ("search_node %p start_node %p return_node %p\n",
355 					scope_info.scope.node, parser_state->start_node, node);
356 
357 
358 			}
359 			else {
360 				/*
361 				 * We got a NOT_FOUND during table load or we encountered
362 				 * a cond_ref_of(x) where the target does not exist.
363 				 * -- either case is ok
364 				 */
365 				status = AE_OK;
366 			}
367 		}
368 	}
369 
370 	/*
371 	 * Regardless of success/failure above,
372 	 * Just initialize the Op with the pathname.
373 	 */
374 	acpi_ps_init_op (arg, AML_INT_NAMEPATH_OP);
375 	arg->common.value.name = path;
376 
377 	return_ACPI_STATUS (status);
378 }
379 
380 
381 /*******************************************************************************
382  *
383  * FUNCTION:    acpi_ps_get_next_simple_arg
384  *
385  * PARAMETERS:  parser_state        - Current parser state object
386  *              arg_type            - The argument type (AML_*_ARG)
387  *              Arg                 - Where the argument is returned
388  *
389  * RETURN:      None
390  *
391  * DESCRIPTION: Get the next simple argument (constant, string, or namestring)
392  *
393  ******************************************************************************/
394 
395 void
acpi_ps_get_next_simple_arg(struct acpi_parse_state * parser_state,u32 arg_type,union acpi_parse_object * arg)396 acpi_ps_get_next_simple_arg (
397 	struct acpi_parse_state         *parser_state,
398 	u32                             arg_type,
399 	union acpi_parse_object         *arg)
400 {
401 
402 	ACPI_FUNCTION_TRACE_U32 ("ps_get_next_simple_arg", arg_type);
403 
404 
405 	switch (arg_type) {
406 	case ARGP_BYTEDATA:
407 
408 		acpi_ps_init_op (arg, AML_BYTE_OP);
409 		arg->common.value.integer = (u32) ACPI_GET8 (parser_state->aml);
410 		parser_state->aml++;
411 		break;
412 
413 
414 	case ARGP_WORDDATA:
415 
416 		acpi_ps_init_op (arg, AML_WORD_OP);
417 
418 		/* Get 2 bytes from the AML stream */
419 
420 		ACPI_MOVE_16_TO_32 (&arg->common.value.integer, parser_state->aml);
421 		parser_state->aml += 2;
422 		break;
423 
424 
425 	case ARGP_DWORDDATA:
426 
427 		acpi_ps_init_op (arg, AML_DWORD_OP);
428 
429 		/* Get 4 bytes from the AML stream */
430 
431 		ACPI_MOVE_32_TO_32 (&arg->common.value.integer, parser_state->aml);
432 		parser_state->aml += 4;
433 		break;
434 
435 
436 	case ARGP_QWORDDATA:
437 
438 		acpi_ps_init_op (arg, AML_QWORD_OP);
439 
440 		/* Get 8 bytes from the AML stream */
441 
442 		ACPI_MOVE_64_TO_64 (&arg->common.value.integer, parser_state->aml);
443 		parser_state->aml += 8;
444 		break;
445 
446 
447 	case ARGP_CHARLIST:
448 
449 		acpi_ps_init_op (arg, AML_STRING_OP);
450 		arg->common.value.string = (char *) parser_state->aml;
451 
452 		while (ACPI_GET8 (parser_state->aml) != '\0') {
453 			parser_state->aml++;
454 		}
455 		parser_state->aml++;
456 		break;
457 
458 
459 	case ARGP_NAME:
460 	case ARGP_NAMESTRING:
461 
462 		acpi_ps_init_op (arg, AML_INT_NAMEPATH_OP);
463 		arg->common.value.name = acpi_ps_get_next_namestring (parser_state);
464 		break;
465 
466 
467 	default:
468 
469 		ACPI_REPORT_ERROR (("Invalid arg_type %X\n", arg_type));
470 		break;
471 	}
472 
473 	return_VOID;
474 }
475 
476 
477 /*******************************************************************************
478  *
479  * FUNCTION:    acpi_ps_get_next_field
480  *
481  * PARAMETERS:  parser_state        - Current parser state object
482  *
483  * RETURN:      A newly allocated FIELD op
484  *
485  * DESCRIPTION: Get next field (named_field, reserved_field, or access_field)
486  *
487  ******************************************************************************/
488 
489 union acpi_parse_object *
acpi_ps_get_next_field(struct acpi_parse_state * parser_state)490 acpi_ps_get_next_field (
491 	struct acpi_parse_state         *parser_state)
492 {
493 	u32                             aml_offset = (u32) ACPI_PTR_DIFF (parser_state->aml,
494 			 parser_state->aml_start);
495 	union acpi_parse_object         *field;
496 	u16                             opcode;
497 	u32                             name;
498 
499 
500 	ACPI_FUNCTION_TRACE ("ps_get_next_field");
501 
502 
503 	/* determine field type */
504 
505 	switch (ACPI_GET8 (parser_state->aml)) {
506 	default:
507 
508 		opcode = AML_INT_NAMEDFIELD_OP;
509 		break;
510 
511 	case 0x00:
512 
513 		opcode = AML_INT_RESERVEDFIELD_OP;
514 		parser_state->aml++;
515 		break;
516 
517 	case 0x01:
518 
519 		opcode = AML_INT_ACCESSFIELD_OP;
520 		parser_state->aml++;
521 		break;
522 	}
523 
524 
525 	/* Allocate a new field op */
526 
527 	field = acpi_ps_alloc_op (opcode);
528 	if (!field) {
529 		return_PTR (NULL);
530 	}
531 
532 	field->common.aml_offset = aml_offset;
533 
534 	/* Decode the field type */
535 
536 	switch (opcode) {
537 	case AML_INT_NAMEDFIELD_OP:
538 
539 		/* Get the 4-character name */
540 
541 		ACPI_MOVE_32_TO_32 (&name, parser_state->aml);
542 		acpi_ps_set_name (field, name);
543 		parser_state->aml += ACPI_NAME_SIZE;
544 
545 		/* Get the length which is encoded as a package length */
546 
547 		field->common.value.size = acpi_ps_get_next_package_length (parser_state);
548 		break;
549 
550 
551 	case AML_INT_RESERVEDFIELD_OP:
552 
553 		/* Get the length which is encoded as a package length */
554 
555 		field->common.value.size = acpi_ps_get_next_package_length (parser_state);
556 		break;
557 
558 
559 	case AML_INT_ACCESSFIELD_OP:
560 
561 		/*
562 		 * Get access_type and access_attrib and merge into the field Op
563 		 * access_type is first operand, access_attribute is second
564 		 */
565 		field->common.value.integer = (ACPI_GET8 (parser_state->aml) << 8);
566 		parser_state->aml++;
567 		field->common.value.integer |= ACPI_GET8 (parser_state->aml);
568 		parser_state->aml++;
569 		break;
570 
571 	default:
572 
573 		/* Opcode was set in previous switch */
574 		break;
575 	}
576 
577 	return_PTR (field);
578 }
579 
580 
581 /*******************************************************************************
582  *
583  * FUNCTION:    acpi_ps_get_next_arg
584  *
585  * PARAMETERS:  parser_state        - Current parser state object
586  *              arg_type            - The argument type (AML_*_ARG)
587  *              arg_count           - If the argument points to a control method
588  *                                    the method's argument is returned here.
589  *
590  * RETURN:      Status, and an op object containing the next argument.
591  *
592  * DESCRIPTION: Get next argument (including complex list arguments that require
593  *              pushing the parser stack)
594  *
595  ******************************************************************************/
596 
597 acpi_status
acpi_ps_get_next_arg(struct acpi_walk_state * walk_state,struct acpi_parse_state * parser_state,u32 arg_type,union acpi_parse_object ** return_arg)598 acpi_ps_get_next_arg (
599 	struct acpi_walk_state          *walk_state,
600 	struct acpi_parse_state         *parser_state,
601 	u32                             arg_type,
602 	union acpi_parse_object         **return_arg)
603 {
604 	union acpi_parse_object         *arg = NULL;
605 	union acpi_parse_object         *prev = NULL;
606 	union acpi_parse_object         *field;
607 	u32                             subop;
608 	acpi_status                     status = AE_OK;
609 
610 
611 	ACPI_FUNCTION_TRACE_PTR ("ps_get_next_arg", parser_state);
612 
613 
614 	switch (arg_type) {
615 	case ARGP_BYTEDATA:
616 	case ARGP_WORDDATA:
617 	case ARGP_DWORDDATA:
618 	case ARGP_CHARLIST:
619 	case ARGP_NAME:
620 	case ARGP_NAMESTRING:
621 
622 		/* constants, strings, and namestrings are all the same size */
623 
624 		arg = acpi_ps_alloc_op (AML_BYTE_OP);
625 		if (!arg) {
626 			return_ACPI_STATUS (AE_NO_MEMORY);
627 		}
628 		acpi_ps_get_next_simple_arg (parser_state, arg_type, arg);
629 		break;
630 
631 
632 	case ARGP_PKGLENGTH:
633 
634 		/* Package length, nothing returned */
635 
636 		parser_state->pkg_end = acpi_ps_get_next_package_end (parser_state);
637 		break;
638 
639 
640 	case ARGP_FIELDLIST:
641 
642 		if (parser_state->aml < parser_state->pkg_end) {
643 			/* Non-empty list */
644 
645 			while (parser_state->aml < parser_state->pkg_end) {
646 				field = acpi_ps_get_next_field (parser_state);
647 				if (!field) {
648 					return_ACPI_STATUS (AE_NO_MEMORY);
649 				}
650 
651 				if (prev) {
652 					prev->common.next = field;
653 				}
654 				else {
655 					arg = field;
656 				}
657 
658 				prev = field;
659 			}
660 
661 			/* Skip to End of byte data */
662 
663 			parser_state->aml = parser_state->pkg_end;
664 		}
665 		break;
666 
667 
668 	case ARGP_BYTELIST:
669 
670 		if (parser_state->aml < parser_state->pkg_end) {
671 			/* Non-empty list */
672 
673 			arg = acpi_ps_alloc_op (AML_INT_BYTELIST_OP);
674 			if (!arg) {
675 				return_ACPI_STATUS (AE_NO_MEMORY);
676 			}
677 
678 			/* Fill in bytelist data */
679 
680 			arg->common.value.size = (u32) ACPI_PTR_DIFF (parser_state->pkg_end,
681 					  parser_state->aml);
682 			arg->named.data = parser_state->aml;
683 
684 			/* Skip to End of byte data */
685 
686 			parser_state->aml = parser_state->pkg_end;
687 		}
688 		break;
689 
690 
691 	case ARGP_TARGET:
692 	case ARGP_SUPERNAME:
693 	case ARGP_SIMPLENAME:
694 
695 		subop = acpi_ps_peek_opcode (parser_state);
696 		if (subop == 0                  ||
697 			acpi_ps_is_leading_char (subop) ||
698 			acpi_ps_is_prefix_char (subop)) {
699 			/* null_name or name_string */
700 
701 			arg = acpi_ps_alloc_op (AML_INT_NAMEPATH_OP);
702 			if (!arg) {
703 				return_ACPI_STATUS (AE_NO_MEMORY);
704 			}
705 
706 			status = acpi_ps_get_next_namepath (walk_state, parser_state, arg, 0);
707 		}
708 		else {
709 			/* single complex argument, nothing returned */
710 
711 			walk_state->arg_count = 1;
712 		}
713 		break;
714 
715 
716 	case ARGP_DATAOBJ:
717 	case ARGP_TERMARG:
718 
719 		/* single complex argument, nothing returned */
720 
721 		walk_state->arg_count = 1;
722 		break;
723 
724 
725 	case ARGP_DATAOBJLIST:
726 	case ARGP_TERMLIST:
727 	case ARGP_OBJLIST:
728 
729 		if (parser_state->aml < parser_state->pkg_end) {
730 			/* non-empty list of variable arguments, nothing returned */
731 
732 			walk_state->arg_count = ACPI_VAR_ARGS;
733 		}
734 		break;
735 
736 
737 	default:
738 
739 		ACPI_REPORT_ERROR (("Invalid arg_type: %X\n", arg_type));
740 		status = AE_AML_OPERAND_TYPE;
741 		break;
742 	}
743 
744 	*return_arg = arg;
745 	return_ACPI_STATUS (status);
746 }
747