xref: /openbmc/linux/drivers/acpi/acpica/psargs.c (revision 9a29f5fc)
1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3  *
4  * Module Name: psargs - Parse AML opcode arguments
5  *
6  * Copyright (C) 2000 - 2022, Intel Corp.
7  *
8  *****************************************************************************/
9 
10 #include <acpi/acpi.h>
11 #include "accommon.h"
12 #include "acparser.h"
13 #include "amlcode.h"
14 #include "acnamesp.h"
15 #include "acdispat.h"
16 #include "acconvert.h"
17 
18 #define _COMPONENT          ACPI_PARSER
19 ACPI_MODULE_NAME("psargs")
20 
21 /* Local prototypes */
22 static u32
23 acpi_ps_get_next_package_length(struct acpi_parse_state *parser_state);
24 
25 static union acpi_parse_object *acpi_ps_get_next_field(struct acpi_parse_state
26 						       *parser_state);
27 
28 /*******************************************************************************
29  *
30  * FUNCTION:    acpi_ps_get_next_package_length
31  *
32  * PARAMETERS:  parser_state        - Current parser state object
33  *
34  * RETURN:      Decoded package length. On completion, the AML pointer points
35  *              past the length byte or bytes.
36  *
37  * DESCRIPTION: Decode and return a package length field.
38  *              Note: Largest package length is 28 bits, from ACPI specification
39  *
40  ******************************************************************************/
41 
42 static u32
43 acpi_ps_get_next_package_length(struct acpi_parse_state *parser_state)
44 {
45 	u8 *aml = parser_state->aml;
46 	u32 package_length = 0;
47 	u32 byte_count;
48 	u8 byte_zero_mask = 0x3F;	/* Default [0:5] */
49 
50 	ACPI_FUNCTION_TRACE(ps_get_next_package_length);
51 
52 	/*
53 	 * Byte 0 bits [6:7] contain the number of additional bytes
54 	 * used to encode the package length, either 0,1,2, or 3
55 	 */
56 	byte_count = (aml[0] >> 6);
57 	parser_state->aml += ((acpi_size)byte_count + 1);
58 
59 	/* Get bytes 3, 2, 1 as needed */
60 
61 	while (byte_count) {
62 		/*
63 		 * Final bit positions for the package length bytes:
64 		 *      Byte3->[20:27]
65 		 *      Byte2->[12:19]
66 		 *      Byte1->[04:11]
67 		 *      Byte0->[00:03]
68 		 */
69 		package_length |= (aml[byte_count] << ((byte_count << 3) - 4));
70 
71 		byte_zero_mask = 0x0F;	/* Use bits [0:3] of byte 0 */
72 		byte_count--;
73 	}
74 
75 	/* Byte 0 is a special case, either bits [0:3] or [0:5] are used */
76 
77 	package_length |= (aml[0] & byte_zero_mask);
78 	return_UINT32(package_length);
79 }
80 
81 /*******************************************************************************
82  *
83  * FUNCTION:    acpi_ps_get_next_package_end
84  *
85  * PARAMETERS:  parser_state        - Current parser state object
86  *
87  * RETURN:      Pointer to end-of-package +1
88  *
89  * DESCRIPTION: Get next package length and return a pointer past the end of
90  *              the package. Consumes the package length field
91  *
92  ******************************************************************************/
93 
94 u8 *acpi_ps_get_next_package_end(struct acpi_parse_state *parser_state)
95 {
96 	u8 *start = parser_state->aml;
97 	u32 package_length;
98 
99 	ACPI_FUNCTION_TRACE(ps_get_next_package_end);
100 
101 	/* Function below updates parser_state->Aml */
102 
103 	package_length = acpi_ps_get_next_package_length(parser_state);
104 
105 	return_PTR(start + package_length);	/* end of package */
106 }
107 
108 /*******************************************************************************
109  *
110  * FUNCTION:    acpi_ps_get_next_namestring
111  *
112  * PARAMETERS:  parser_state        - Current parser state object
113  *
114  * RETURN:      Pointer to the start of the name string (pointer points into
115  *              the AML.
116  *
117  * DESCRIPTION: Get next raw namestring within the AML stream. Handles all name
118  *              prefix characters. Set parser state to point past the string.
119  *              (Name is consumed from the AML.)
120  *
121  ******************************************************************************/
122 
123 char *acpi_ps_get_next_namestring(struct acpi_parse_state *parser_state)
124 {
125 	u8 *start = parser_state->aml;
126 	u8 *end = parser_state->aml;
127 
128 	ACPI_FUNCTION_TRACE(ps_get_next_namestring);
129 
130 	/* Point past any namestring prefix characters (backslash or carat) */
131 
132 	while (ACPI_IS_ROOT_PREFIX(*end) || ACPI_IS_PARENT_PREFIX(*end)) {
133 		end++;
134 	}
135 
136 	/* Decode the path prefix character */
137 
138 	switch (*end) {
139 	case 0:
140 
141 		/* null_name */
142 
143 		if (end == start) {
144 			start = NULL;
145 		}
146 		end++;
147 		break;
148 
149 	case AML_DUAL_NAME_PREFIX:
150 
151 		/* Two name segments */
152 
153 		end += 1 + (2 * ACPI_NAMESEG_SIZE);
154 		break;
155 
156 	case AML_MULTI_NAME_PREFIX:
157 
158 		/* Multiple name segments, 4 chars each, count in next byte */
159 
160 		end += 2 + (*(end + 1) * ACPI_NAMESEG_SIZE);
161 		break;
162 
163 	default:
164 
165 		/* Single name segment */
166 
167 		end += ACPI_NAMESEG_SIZE;
168 		break;
169 	}
170 
171 	parser_state->aml = end;
172 	return_PTR((char *)start);
173 }
174 
175 /*******************************************************************************
176  *
177  * FUNCTION:    acpi_ps_get_next_namepath
178  *
179  * PARAMETERS:  parser_state        - Current parser state object
180  *              arg                 - Where the namepath will be stored
181  *              arg_count           - If the namepath points to a control method
182  *                                    the method's argument is returned here.
183  *              possible_method_call - Whether the namepath can possibly be the
184  *                                    start of a method call
185  *
186  * RETURN:      Status
187  *
188  * DESCRIPTION: Get next name (if method call, return # of required args).
189  *              Names are looked up in the internal namespace to determine
190  *              if the name represents a control method. If a method
191  *              is found, the number of arguments to the method is returned.
192  *              This information is critical for parsing to continue correctly.
193  *
194  ******************************************************************************/
195 
196 acpi_status
197 acpi_ps_get_next_namepath(struct acpi_walk_state *walk_state,
198 			  struct acpi_parse_state *parser_state,
199 			  union acpi_parse_object *arg, u8 possible_method_call)
200 {
201 	acpi_status status;
202 	char *path;
203 	union acpi_parse_object *name_op;
204 	union acpi_operand_object *method_desc;
205 	struct acpi_namespace_node *node;
206 	u8 *start = parser_state->aml;
207 
208 	ACPI_FUNCTION_TRACE(ps_get_next_namepath);
209 
210 	path = acpi_ps_get_next_namestring(parser_state);
211 	acpi_ps_init_op(arg, AML_INT_NAMEPATH_OP);
212 
213 	/* Null path case is allowed, just exit */
214 
215 	if (!path) {
216 		arg->common.value.name = path;
217 		return_ACPI_STATUS(AE_OK);
218 	}
219 
220 	/*
221 	 * Lookup the name in the internal namespace, starting with the current
222 	 * scope. We don't want to add anything new to the namespace here,
223 	 * however, so we use MODE_EXECUTE.
224 	 * Allow searching of the parent tree, but don't open a new scope -
225 	 * we just want to lookup the object (must be mode EXECUTE to perform
226 	 * the upsearch)
227 	 */
228 	status = acpi_ns_lookup(walk_state->scope_info, path,
229 				ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,
230 				ACPI_NS_SEARCH_PARENT | ACPI_NS_DONT_OPEN_SCOPE,
231 				NULL, &node);
232 
233 	/*
234 	 * If this name is a control method invocation, we must
235 	 * setup the method call
236 	 */
237 	if (ACPI_SUCCESS(status) &&
238 	    possible_method_call && (node->type == ACPI_TYPE_METHOD)) {
239 		if ((GET_CURRENT_ARG_TYPE(walk_state->arg_types) ==
240 		     ARGP_SUPERNAME)
241 		    || (GET_CURRENT_ARG_TYPE(walk_state->arg_types) ==
242 			ARGP_TARGET)) {
243 			/*
244 			 * acpi_ps_get_next_namestring has increased the AML pointer past
245 			 * the method invocation namestring, so we need to restore the
246 			 * saved AML pointer back to the original method invocation
247 			 * namestring.
248 			 */
249 			walk_state->parser_state.aml = start;
250 			walk_state->arg_count = 1;
251 			acpi_ps_init_op(arg, AML_INT_METHODCALL_OP);
252 		}
253 
254 		/* This name is actually a control method invocation */
255 
256 		method_desc = acpi_ns_get_attached_object(node);
257 		ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
258 				  "Control Method invocation %4.4s - %p Desc %p Path=%p\n",
259 				  node->name.ascii, node, method_desc, path));
260 
261 		name_op = acpi_ps_alloc_op(AML_INT_NAMEPATH_OP, start);
262 		if (!name_op) {
263 			return_ACPI_STATUS(AE_NO_MEMORY);
264 		}
265 
266 		/* Change Arg into a METHOD CALL and attach name to it */
267 
268 		acpi_ps_init_op(arg, AML_INT_METHODCALL_OP);
269 		name_op->common.value.name = path;
270 
271 		/* Point METHODCALL/NAME to the METHOD Node */
272 
273 		name_op->common.node = node;
274 		acpi_ps_append_arg(arg, name_op);
275 
276 		if (!method_desc) {
277 			ACPI_ERROR((AE_INFO,
278 				    "Control Method %p has no attached object",
279 				    node));
280 			return_ACPI_STATUS(AE_AML_INTERNAL);
281 		}
282 
283 		ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
284 				  "Control Method - %p Args %X\n",
285 				  node, method_desc->method.param_count));
286 
287 		/* Get the number of arguments to expect */
288 
289 		walk_state->arg_count = method_desc->method.param_count;
290 		return_ACPI_STATUS(AE_OK);
291 	}
292 
293 	/*
294 	 * Special handling if the name was not found during the lookup -
295 	 * some not_found cases are allowed
296 	 */
297 	if (status == AE_NOT_FOUND) {
298 
299 		/* 1) not_found is ok during load pass 1/2 (allow forward references) */
300 
301 		if ((walk_state->parse_flags & ACPI_PARSE_MODE_MASK) !=
302 		    ACPI_PARSE_EXECUTE) {
303 			status = AE_OK;
304 		}
305 
306 		/* 2) not_found during a cond_ref_of(x) is ok by definition */
307 
308 		else if (walk_state->op->common.aml_opcode ==
309 			 AML_CONDITIONAL_REF_OF_OP) {
310 			status = AE_OK;
311 		}
312 
313 		/*
314 		 * 3) not_found while building a Package is ok at this point, we
315 		 * may flag as an error later if slack mode is not enabled.
316 		 * (Some ASL code depends on allowing this behavior)
317 		 */
318 		else if ((arg->common.parent) &&
319 			 ((arg->common.parent->common.aml_opcode ==
320 			   AML_PACKAGE_OP)
321 			  || (arg->common.parent->common.aml_opcode ==
322 			      AML_VARIABLE_PACKAGE_OP))) {
323 			status = AE_OK;
324 		}
325 	}
326 
327 	/* Final exception check (may have been changed from code above) */
328 
329 	if (ACPI_FAILURE(status)) {
330 		ACPI_ERROR_NAMESPACE(walk_state->scope_info, path, status);
331 
332 		if ((walk_state->parse_flags & ACPI_PARSE_MODE_MASK) ==
333 		    ACPI_PARSE_EXECUTE) {
334 
335 			/* Report a control method execution error */
336 
337 			status = acpi_ds_method_error(status, walk_state);
338 		}
339 	}
340 
341 	/* Save the namepath */
342 
343 	arg->common.value.name = path;
344 	return_ACPI_STATUS(status);
345 }
346 
347 /*******************************************************************************
348  *
349  * FUNCTION:    acpi_ps_get_next_simple_arg
350  *
351  * PARAMETERS:  parser_state        - Current parser state object
352  *              arg_type            - The argument type (AML_*_ARG)
353  *              arg                 - Where the argument is returned
354  *
355  * RETURN:      None
356  *
357  * DESCRIPTION: Get the next simple argument (constant, string, or namestring)
358  *
359  ******************************************************************************/
360 
361 void
362 acpi_ps_get_next_simple_arg(struct acpi_parse_state *parser_state,
363 			    u32 arg_type, union acpi_parse_object *arg)
364 {
365 	u32 length;
366 	u16 opcode;
367 	u8 *aml = parser_state->aml;
368 
369 	ACPI_FUNCTION_TRACE_U32(ps_get_next_simple_arg, arg_type);
370 
371 	switch (arg_type) {
372 	case ARGP_BYTEDATA:
373 
374 		/* Get 1 byte from the AML stream */
375 
376 		opcode = AML_BYTE_OP;
377 		arg->common.value.integer = (u64) *aml;
378 		length = 1;
379 		break;
380 
381 	case ARGP_WORDDATA:
382 
383 		/* Get 2 bytes from the AML stream */
384 
385 		opcode = AML_WORD_OP;
386 		ACPI_MOVE_16_TO_64(&arg->common.value.integer, aml);
387 		length = 2;
388 		break;
389 
390 	case ARGP_DWORDDATA:
391 
392 		/* Get 4 bytes from the AML stream */
393 
394 		opcode = AML_DWORD_OP;
395 		ACPI_MOVE_32_TO_64(&arg->common.value.integer, aml);
396 		length = 4;
397 		break;
398 
399 	case ARGP_QWORDDATA:
400 
401 		/* Get 8 bytes from the AML stream */
402 
403 		opcode = AML_QWORD_OP;
404 		ACPI_MOVE_64_TO_64(&arg->common.value.integer, aml);
405 		length = 8;
406 		break;
407 
408 	case ARGP_CHARLIST:
409 
410 		/* Get a pointer to the string, point past the string */
411 
412 		opcode = AML_STRING_OP;
413 		arg->common.value.string = ACPI_CAST_PTR(char, aml);
414 
415 		/* Find the null terminator */
416 
417 		length = 0;
418 		while (aml[length]) {
419 			length++;
420 		}
421 		length++;
422 		break;
423 
424 	case ARGP_NAME:
425 	case ARGP_NAMESTRING:
426 
427 		acpi_ps_init_op(arg, AML_INT_NAMEPATH_OP);
428 		arg->common.value.name =
429 		    acpi_ps_get_next_namestring(parser_state);
430 		return_VOID;
431 
432 	default:
433 
434 		ACPI_ERROR((AE_INFO, "Invalid ArgType 0x%X", arg_type));
435 		return_VOID;
436 	}
437 
438 	acpi_ps_init_op(arg, opcode);
439 	parser_state->aml += length;
440 	return_VOID;
441 }
442 
443 /*******************************************************************************
444  *
445  * FUNCTION:    acpi_ps_get_next_field
446  *
447  * PARAMETERS:  parser_state        - Current parser state object
448  *
449  * RETURN:      A newly allocated FIELD op
450  *
451  * DESCRIPTION: Get next field (named_field, reserved_field, or access_field)
452  *
453  ******************************************************************************/
454 
455 static union acpi_parse_object *acpi_ps_get_next_field(struct acpi_parse_state
456 						       *parser_state)
457 {
458 	u8 *aml;
459 	union acpi_parse_object *field;
460 	union acpi_parse_object *arg = NULL;
461 	u16 opcode;
462 	u32 name;
463 	u8 access_type;
464 	u8 access_attribute;
465 	u8 access_length;
466 	u32 pkg_length;
467 	u8 *pkg_end;
468 	u32 buffer_length;
469 
470 	ACPI_FUNCTION_TRACE(ps_get_next_field);
471 
472 	ASL_CV_CAPTURE_COMMENTS_ONLY(parser_state);
473 	aml = parser_state->aml;
474 
475 	/* Determine field type */
476 
477 	switch (ACPI_GET8(parser_state->aml)) {
478 	case AML_FIELD_OFFSET_OP:
479 
480 		opcode = AML_INT_RESERVEDFIELD_OP;
481 		parser_state->aml++;
482 		break;
483 
484 	case AML_FIELD_ACCESS_OP:
485 
486 		opcode = AML_INT_ACCESSFIELD_OP;
487 		parser_state->aml++;
488 		break;
489 
490 	case AML_FIELD_CONNECTION_OP:
491 
492 		opcode = AML_INT_CONNECTION_OP;
493 		parser_state->aml++;
494 		break;
495 
496 	case AML_FIELD_EXT_ACCESS_OP:
497 
498 		opcode = AML_INT_EXTACCESSFIELD_OP;
499 		parser_state->aml++;
500 		break;
501 
502 	default:
503 
504 		opcode = AML_INT_NAMEDFIELD_OP;
505 		break;
506 	}
507 
508 	/* Allocate a new field op */
509 
510 	field = acpi_ps_alloc_op(opcode, aml);
511 	if (!field) {
512 		return_PTR(NULL);
513 	}
514 
515 	/* Decode the field type */
516 
517 	ASL_CV_CAPTURE_COMMENTS_ONLY(parser_state);
518 	switch (opcode) {
519 	case AML_INT_NAMEDFIELD_OP:
520 
521 		/* Get the 4-character name */
522 
523 		ACPI_MOVE_32_TO_32(&name, parser_state->aml);
524 		acpi_ps_set_name(field, name);
525 		parser_state->aml += ACPI_NAMESEG_SIZE;
526 
527 		ASL_CV_CAPTURE_COMMENTS_ONLY(parser_state);
528 
529 #ifdef ACPI_ASL_COMPILER
530 		/*
531 		 * Because the package length isn't represented as a parse tree object,
532 		 * take comments surrounding this and add to the previously created
533 		 * parse node.
534 		 */
535 		if (field->common.inline_comment) {
536 			field->common.name_comment =
537 			    field->common.inline_comment;
538 		}
539 		field->common.inline_comment = acpi_gbl_current_inline_comment;
540 		acpi_gbl_current_inline_comment = NULL;
541 #endif
542 
543 		/* Get the length which is encoded as a package length */
544 
545 		field->common.value.size =
546 		    acpi_ps_get_next_package_length(parser_state);
547 		break;
548 
549 	case AML_INT_RESERVEDFIELD_OP:
550 
551 		/* Get the length which is encoded as a package length */
552 
553 		field->common.value.size =
554 		    acpi_ps_get_next_package_length(parser_state);
555 		break;
556 
557 	case AML_INT_ACCESSFIELD_OP:
558 	case AML_INT_EXTACCESSFIELD_OP:
559 
560 		/*
561 		 * Get access_type and access_attrib and merge into the field Op
562 		 * access_type is first operand, access_attribute is second. stuff
563 		 * these bytes into the node integer value for convenience.
564 		 */
565 
566 		/* Get the two bytes (Type/Attribute) */
567 
568 		access_type = ACPI_GET8(parser_state->aml);
569 		parser_state->aml++;
570 		access_attribute = ACPI_GET8(parser_state->aml);
571 		parser_state->aml++;
572 
573 		field->common.value.integer = (u8)access_type;
574 		field->common.value.integer |= (u16)(access_attribute << 8);
575 
576 		/* This opcode has a third byte, access_length */
577 
578 		if (opcode == AML_INT_EXTACCESSFIELD_OP) {
579 			access_length = ACPI_GET8(parser_state->aml);
580 			parser_state->aml++;
581 
582 			field->common.value.integer |=
583 			    (u32)(access_length << 16);
584 		}
585 		break;
586 
587 	case AML_INT_CONNECTION_OP:
588 
589 		/*
590 		 * Argument for Connection operator can be either a Buffer
591 		 * (resource descriptor), or a name_string.
592 		 */
593 		aml = parser_state->aml;
594 		if (ACPI_GET8(parser_state->aml) == AML_BUFFER_OP) {
595 			parser_state->aml++;
596 
597 			ASL_CV_CAPTURE_COMMENTS_ONLY(parser_state);
598 			pkg_end = parser_state->aml;
599 			pkg_length =
600 			    acpi_ps_get_next_package_length(parser_state);
601 			pkg_end += pkg_length;
602 
603 			ASL_CV_CAPTURE_COMMENTS_ONLY(parser_state);
604 			if (parser_state->aml < pkg_end) {
605 
606 				/* Non-empty list */
607 
608 				arg =
609 				    acpi_ps_alloc_op(AML_INT_BYTELIST_OP, aml);
610 				if (!arg) {
611 					acpi_ps_free_op(field);
612 					return_PTR(NULL);
613 				}
614 
615 				/* Get the actual buffer length argument */
616 
617 				opcode = ACPI_GET8(parser_state->aml);
618 				parser_state->aml++;
619 
620 				ASL_CV_CAPTURE_COMMENTS_ONLY(parser_state);
621 				switch (opcode) {
622 				case AML_BYTE_OP:	/* AML_BYTEDATA_ARG */
623 
624 					buffer_length =
625 					    ACPI_GET8(parser_state->aml);
626 					parser_state->aml += 1;
627 					break;
628 
629 				case AML_WORD_OP:	/* AML_WORDDATA_ARG */
630 
631 					buffer_length =
632 					    ACPI_GET16(parser_state->aml);
633 					parser_state->aml += 2;
634 					break;
635 
636 				case AML_DWORD_OP:	/* AML_DWORDATA_ARG */
637 
638 					buffer_length =
639 					    ACPI_GET32(parser_state->aml);
640 					parser_state->aml += 4;
641 					break;
642 
643 				default:
644 
645 					buffer_length = 0;
646 					break;
647 				}
648 
649 				/* Fill in bytelist data */
650 
651 				ASL_CV_CAPTURE_COMMENTS_ONLY(parser_state);
652 				arg->named.value.size = buffer_length;
653 				arg->named.data = parser_state->aml;
654 			}
655 
656 			/* Skip to End of byte data */
657 
658 			parser_state->aml = pkg_end;
659 		} else {
660 			arg = acpi_ps_alloc_op(AML_INT_NAMEPATH_OP, aml);
661 			if (!arg) {
662 				acpi_ps_free_op(field);
663 				return_PTR(NULL);
664 			}
665 
666 			/* Get the Namestring argument */
667 
668 			arg->common.value.name =
669 			    acpi_ps_get_next_namestring(parser_state);
670 		}
671 
672 		/* Link the buffer/namestring to parent (CONNECTION_OP) */
673 
674 		acpi_ps_append_arg(field, arg);
675 		break;
676 
677 	default:
678 
679 		/* Opcode was set in previous switch */
680 		break;
681 	}
682 
683 	return_PTR(field);
684 }
685 
686 /*******************************************************************************
687  *
688  * FUNCTION:    acpi_ps_get_next_arg
689  *
690  * PARAMETERS:  walk_state          - Current state
691  *              parser_state        - Current parser state object
692  *              arg_type            - The argument type (AML_*_ARG)
693  *              return_arg          - Where the next arg is returned
694  *
695  * RETURN:      Status, and an op object containing the next argument.
696  *
697  * DESCRIPTION: Get next argument (including complex list arguments that require
698  *              pushing the parser stack)
699  *
700  ******************************************************************************/
701 
702 acpi_status
703 acpi_ps_get_next_arg(struct acpi_walk_state *walk_state,
704 		     struct acpi_parse_state *parser_state,
705 		     u32 arg_type, union acpi_parse_object **return_arg)
706 {
707 	union acpi_parse_object *arg = NULL;
708 	union acpi_parse_object *prev = NULL;
709 	union acpi_parse_object *field;
710 	u32 subop;
711 	acpi_status status = AE_OK;
712 
713 	ACPI_FUNCTION_TRACE_PTR(ps_get_next_arg, parser_state);
714 
715 	ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
716 			  "Expected argument type ARGP: %s (%2.2X)\n",
717 			  acpi_ut_get_argument_type_name(arg_type), arg_type));
718 
719 	switch (arg_type) {
720 	case ARGP_BYTEDATA:
721 	case ARGP_WORDDATA:
722 	case ARGP_DWORDDATA:
723 	case ARGP_CHARLIST:
724 	case ARGP_NAME:
725 	case ARGP_NAMESTRING:
726 
727 		/* Constants, strings, and namestrings are all the same size */
728 
729 		arg = acpi_ps_alloc_op(AML_BYTE_OP, parser_state->aml);
730 		if (!arg) {
731 			return_ACPI_STATUS(AE_NO_MEMORY);
732 		}
733 
734 		acpi_ps_get_next_simple_arg(parser_state, arg_type, arg);
735 		break;
736 
737 	case ARGP_PKGLENGTH:
738 
739 		/* Package length, nothing returned */
740 
741 		parser_state->pkg_end =
742 		    acpi_ps_get_next_package_end(parser_state);
743 		break;
744 
745 	case ARGP_FIELDLIST:
746 
747 		if (parser_state->aml < parser_state->pkg_end) {
748 
749 			/* Non-empty list */
750 
751 			while (parser_state->aml < parser_state->pkg_end) {
752 				field = acpi_ps_get_next_field(parser_state);
753 				if (!field) {
754 					return_ACPI_STATUS(AE_NO_MEMORY);
755 				}
756 
757 				if (prev) {
758 					prev->common.next = field;
759 				} else {
760 					arg = field;
761 				}
762 				prev = field;
763 			}
764 
765 			/* Skip to End of byte data */
766 
767 			parser_state->aml = parser_state->pkg_end;
768 		}
769 		break;
770 
771 	case ARGP_BYTELIST:
772 
773 		if (parser_state->aml < parser_state->pkg_end) {
774 
775 			/* Non-empty list */
776 
777 			arg = acpi_ps_alloc_op(AML_INT_BYTELIST_OP,
778 					       parser_state->aml);
779 			if (!arg) {
780 				return_ACPI_STATUS(AE_NO_MEMORY);
781 			}
782 
783 			/* Fill in bytelist data */
784 
785 			arg->common.value.size = (u32)
786 			    ACPI_PTR_DIFF(parser_state->pkg_end,
787 					  parser_state->aml);
788 			arg->named.data = parser_state->aml;
789 
790 			/* Skip to End of byte data */
791 
792 			parser_state->aml = parser_state->pkg_end;
793 		}
794 		break;
795 
796 	case ARGP_SIMPLENAME:
797 	case ARGP_NAME_OR_REF:
798 
799 		ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
800 				  "**** SimpleName/NameOrRef: %s (%2.2X)\n",
801 				  acpi_ut_get_argument_type_name(arg_type),
802 				  arg_type));
803 
804 		subop = acpi_ps_peek_opcode(parser_state);
805 		if (subop == 0 ||
806 		    acpi_ps_is_leading_char(subop) ||
807 		    ACPI_IS_ROOT_PREFIX(subop) ||
808 		    ACPI_IS_PARENT_PREFIX(subop)) {
809 
810 			/* null_name or name_string */
811 
812 			arg =
813 			    acpi_ps_alloc_op(AML_INT_NAMEPATH_OP,
814 					     parser_state->aml);
815 			if (!arg) {
816 				return_ACPI_STATUS(AE_NO_MEMORY);
817 			}
818 
819 			status =
820 			    acpi_ps_get_next_namepath(walk_state, parser_state,
821 						      arg,
822 						      ACPI_NOT_METHOD_CALL);
823 		} else {
824 			/* Single complex argument, nothing returned */
825 
826 			walk_state->arg_count = 1;
827 		}
828 		break;
829 
830 	case ARGP_TARGET:
831 	case ARGP_SUPERNAME:
832 
833 		ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
834 				  "**** Target/Supername: %s (%2.2X)\n",
835 				  acpi_ut_get_argument_type_name(arg_type),
836 				  arg_type));
837 
838 		subop = acpi_ps_peek_opcode(parser_state);
839 		if (subop == 0 ||
840 		    acpi_ps_is_leading_char(subop) ||
841 		    ACPI_IS_ROOT_PREFIX(subop) ||
842 		    ACPI_IS_PARENT_PREFIX(subop)) {
843 
844 			/* NULL target (zero). Convert to a NULL namepath */
845 
846 			arg =
847 			    acpi_ps_alloc_op(AML_INT_NAMEPATH_OP,
848 					     parser_state->aml);
849 			if (!arg) {
850 				return_ACPI_STATUS(AE_NO_MEMORY);
851 			}
852 
853 			status =
854 			    acpi_ps_get_next_namepath(walk_state, parser_state,
855 						      arg,
856 						      ACPI_POSSIBLE_METHOD_CALL);
857 
858 			if (arg->common.aml_opcode == AML_INT_METHODCALL_OP) {
859 
860 				/* Free method call op and corresponding namestring sub-ob */
861 
862 				acpi_ps_free_op(arg->common.value.arg);
863 				acpi_ps_free_op(arg);
864 				arg = NULL;
865 				walk_state->arg_count = 1;
866 			}
867 		} else {
868 			/* Single complex argument, nothing returned */
869 
870 			walk_state->arg_count = 1;
871 		}
872 		break;
873 
874 	case ARGP_DATAOBJ:
875 	case ARGP_TERMARG:
876 
877 		ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
878 				  "**** TermArg/DataObj: %s (%2.2X)\n",
879 				  acpi_ut_get_argument_type_name(arg_type),
880 				  arg_type));
881 
882 		/* Single complex argument, nothing returned */
883 
884 		walk_state->arg_count = 1;
885 		break;
886 
887 	case ARGP_DATAOBJLIST:
888 	case ARGP_TERMLIST:
889 	case ARGP_OBJLIST:
890 
891 		if (parser_state->aml < parser_state->pkg_end) {
892 
893 			/* Non-empty list of variable arguments, nothing returned */
894 
895 			walk_state->arg_count = ACPI_VAR_ARGS;
896 		}
897 		break;
898 
899 	default:
900 
901 		ACPI_ERROR((AE_INFO, "Invalid ArgType: 0x%X", arg_type));
902 		status = AE_AML_OPERAND_TYPE;
903 		break;
904 	}
905 
906 	*return_arg = arg;
907 	return_ACPI_STATUS(status);
908 }
909