xref: /openbmc/linux/drivers/acpi/acpica/dsmthdat.c (revision 5e29a910)
1 /*******************************************************************************
2  *
3  * Module Name: dsmthdat - control method arguments and local variables
4  *
5  ******************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2015, Intel Corp.
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 #include <acpi/acpi.h>
45 #include "accommon.h"
46 #include "acdispat.h"
47 #include "acnamesp.h"
48 #include "acinterp.h"
49 
50 #define _COMPONENT          ACPI_DISPATCHER
51 ACPI_MODULE_NAME("dsmthdat")
52 
53 /* Local prototypes */
54 static void
55 acpi_ds_method_data_delete_value(u8 type,
56 				 u32 index, struct acpi_walk_state *walk_state);
57 
58 static acpi_status
59 acpi_ds_method_data_set_value(u8 type,
60 			      u32 index,
61 			      union acpi_operand_object *object,
62 			      struct acpi_walk_state *walk_state);
63 
64 #ifdef ACPI_OBSOLETE_FUNCTIONS
65 acpi_object_type
66 acpi_ds_method_data_get_type(u16 opcode,
67 			     u32 index, struct acpi_walk_state *walk_state);
68 #endif
69 
70 /*******************************************************************************
71  *
72  * FUNCTION:    acpi_ds_method_data_init
73  *
74  * PARAMETERS:  walk_state          - Current walk state object
75  *
76  * RETURN:      Status
77  *
78  * DESCRIPTION: Initialize the data structures that hold the method's arguments
79  *              and locals. The data struct is an array of namespace nodes for
80  *              each - this allows ref_of and de_ref_of to work properly for these
81  *              special data types.
82  *
83  * NOTES:       walk_state fields are initialized to zero by the
84  *              ACPI_ALLOCATE_ZEROED().
85  *
86  *              A pseudo-Namespace Node is assigned to each argument and local
87  *              so that ref_of() can return a pointer to the Node.
88  *
89  ******************************************************************************/
90 
91 void acpi_ds_method_data_init(struct acpi_walk_state *walk_state)
92 {
93 	u32 i;
94 
95 	ACPI_FUNCTION_TRACE(ds_method_data_init);
96 
97 	/* Init the method arguments */
98 
99 	for (i = 0; i < ACPI_METHOD_NUM_ARGS; i++) {
100 		ACPI_MOVE_32_TO_32(&walk_state->arguments[i].name,
101 				   NAMEOF_ARG_NTE);
102 		walk_state->arguments[i].name.integer |= (i << 24);
103 		walk_state->arguments[i].descriptor_type = ACPI_DESC_TYPE_NAMED;
104 		walk_state->arguments[i].type = ACPI_TYPE_ANY;
105 		walk_state->arguments[i].flags = ANOBJ_METHOD_ARG;
106 	}
107 
108 	/* Init the method locals */
109 
110 	for (i = 0; i < ACPI_METHOD_NUM_LOCALS; i++) {
111 		ACPI_MOVE_32_TO_32(&walk_state->local_variables[i].name,
112 				   NAMEOF_LOCAL_NTE);
113 
114 		walk_state->local_variables[i].name.integer |= (i << 24);
115 		walk_state->local_variables[i].descriptor_type =
116 		    ACPI_DESC_TYPE_NAMED;
117 		walk_state->local_variables[i].type = ACPI_TYPE_ANY;
118 		walk_state->local_variables[i].flags = ANOBJ_METHOD_LOCAL;
119 	}
120 
121 	return_VOID;
122 }
123 
124 /*******************************************************************************
125  *
126  * FUNCTION:    acpi_ds_method_data_delete_all
127  *
128  * PARAMETERS:  walk_state          - Current walk state object
129  *
130  * RETURN:      None
131  *
132  * DESCRIPTION: Delete method locals and arguments. Arguments are only
133  *              deleted if this method was called from another method.
134  *
135  ******************************************************************************/
136 
137 void acpi_ds_method_data_delete_all(struct acpi_walk_state *walk_state)
138 {
139 	u32 index;
140 
141 	ACPI_FUNCTION_TRACE(ds_method_data_delete_all);
142 
143 	/* Detach the locals */
144 
145 	for (index = 0; index < ACPI_METHOD_NUM_LOCALS; index++) {
146 		if (walk_state->local_variables[index].object) {
147 			ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Deleting Local%u=%p\n",
148 					  index,
149 					  walk_state->local_variables[index].
150 					  object));
151 
152 			/* Detach object (if present) and remove a reference */
153 
154 			acpi_ns_detach_object(&walk_state->
155 					      local_variables[index]);
156 		}
157 	}
158 
159 	/* Detach the arguments */
160 
161 	for (index = 0; index < ACPI_METHOD_NUM_ARGS; index++) {
162 		if (walk_state->arguments[index].object) {
163 			ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Deleting Arg%u=%p\n",
164 					  index,
165 					  walk_state->arguments[index].object));
166 
167 			/* Detach object (if present) and remove a reference */
168 
169 			acpi_ns_detach_object(&walk_state->arguments[index]);
170 		}
171 	}
172 
173 	return_VOID;
174 }
175 
176 /*******************************************************************************
177  *
178  * FUNCTION:    acpi_ds_method_data_init_args
179  *
180  * PARAMETERS:  *params         - Pointer to a parameter list for the method
181  *              max_param_count - The arg count for this method
182  *              walk_state      - Current walk state object
183  *
184  * RETURN:      Status
185  *
186  * DESCRIPTION: Initialize arguments for a method. The parameter list is a list
187  *              of ACPI operand objects, either null terminated or whose length
188  *              is defined by max_param_count.
189  *
190  ******************************************************************************/
191 
192 acpi_status
193 acpi_ds_method_data_init_args(union acpi_operand_object **params,
194 			      u32 max_param_count,
195 			      struct acpi_walk_state *walk_state)
196 {
197 	acpi_status status;
198 	u32 index = 0;
199 
200 	ACPI_FUNCTION_TRACE_PTR(ds_method_data_init_args, params);
201 
202 	if (!params) {
203 		ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
204 				  "No param list passed to method\n"));
205 		return_ACPI_STATUS(AE_OK);
206 	}
207 
208 	/* Copy passed parameters into the new method stack frame */
209 
210 	while ((index < ACPI_METHOD_NUM_ARGS) &&
211 	       (index < max_param_count) && params[index]) {
212 		/*
213 		 * A valid parameter.
214 		 * Store the argument in the method/walk descriptor.
215 		 * Do not copy the arg in order to implement call by reference
216 		 */
217 		status = acpi_ds_method_data_set_value(ACPI_REFCLASS_ARG, index,
218 						       params[index],
219 						       walk_state);
220 		if (ACPI_FAILURE(status)) {
221 			return_ACPI_STATUS(status);
222 		}
223 
224 		index++;
225 	}
226 
227 	ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "%u args passed to method\n", index));
228 	return_ACPI_STATUS(AE_OK);
229 }
230 
231 /*******************************************************************************
232  *
233  * FUNCTION:    acpi_ds_method_data_get_node
234  *
235  * PARAMETERS:  type                - Either ACPI_REFCLASS_LOCAL or
236  *                                    ACPI_REFCLASS_ARG
237  *              index               - Which Local or Arg whose type to get
238  *              walk_state          - Current walk state object
239  *              node                - Where the node is returned.
240  *
241  * RETURN:      Status and node
242  *
243  * DESCRIPTION: Get the Node associated with a local or arg.
244  *
245  ******************************************************************************/
246 
247 acpi_status
248 acpi_ds_method_data_get_node(u8 type,
249 			     u32 index,
250 			     struct acpi_walk_state *walk_state,
251 			     struct acpi_namespace_node **node)
252 {
253 	ACPI_FUNCTION_TRACE(ds_method_data_get_node);
254 
255 	/*
256 	 * Method Locals and Arguments are supported
257 	 */
258 	switch (type) {
259 	case ACPI_REFCLASS_LOCAL:
260 
261 		if (index > ACPI_METHOD_MAX_LOCAL) {
262 			ACPI_ERROR((AE_INFO,
263 				    "Local index %u is invalid (max %u)",
264 				    index, ACPI_METHOD_MAX_LOCAL));
265 			return_ACPI_STATUS(AE_AML_INVALID_INDEX);
266 		}
267 
268 		/* Return a pointer to the pseudo-node */
269 
270 		*node = &walk_state->local_variables[index];
271 		break;
272 
273 	case ACPI_REFCLASS_ARG:
274 
275 		if (index > ACPI_METHOD_MAX_ARG) {
276 			ACPI_ERROR((AE_INFO,
277 				    "Arg index %u is invalid (max %u)",
278 				    index, ACPI_METHOD_MAX_ARG));
279 			return_ACPI_STATUS(AE_AML_INVALID_INDEX);
280 		}
281 
282 		/* Return a pointer to the pseudo-node */
283 
284 		*node = &walk_state->arguments[index];
285 		break;
286 
287 	default:
288 
289 		ACPI_ERROR((AE_INFO, "Type %u is invalid", type));
290 		return_ACPI_STATUS(AE_TYPE);
291 	}
292 
293 	return_ACPI_STATUS(AE_OK);
294 }
295 
296 /*******************************************************************************
297  *
298  * FUNCTION:    acpi_ds_method_data_set_value
299  *
300  * PARAMETERS:  type                - Either ACPI_REFCLASS_LOCAL or
301  *                                    ACPI_REFCLASS_ARG
302  *              index               - Which Local or Arg to get
303  *              object              - Object to be inserted into the stack entry
304  *              walk_state          - Current walk state object
305  *
306  * RETURN:      Status
307  *
308  * DESCRIPTION: Insert an object onto the method stack at entry Opcode:Index.
309  *              Note: There is no "implicit conversion" for locals.
310  *
311  ******************************************************************************/
312 
313 static acpi_status
314 acpi_ds_method_data_set_value(u8 type,
315 			      u32 index,
316 			      union acpi_operand_object *object,
317 			      struct acpi_walk_state *walk_state)
318 {
319 	acpi_status status;
320 	struct acpi_namespace_node *node;
321 
322 	ACPI_FUNCTION_TRACE(ds_method_data_set_value);
323 
324 	ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
325 			  "NewObj %p Type %2.2X, Refs=%u [%s]\n", object,
326 			  type, object->common.reference_count,
327 			  acpi_ut_get_type_name(object->common.type)));
328 
329 	/* Get the namespace node for the arg/local */
330 
331 	status = acpi_ds_method_data_get_node(type, index, walk_state, &node);
332 	if (ACPI_FAILURE(status)) {
333 		return_ACPI_STATUS(status);
334 	}
335 
336 	/*
337 	 * Increment ref count so object can't be deleted while installed.
338 	 * NOTE: We do not copy the object in order to preserve the call by
339 	 * reference semantics of ACPI Control Method invocation.
340 	 * (See ACPI Specification 2.0C)
341 	 */
342 	acpi_ut_add_reference(object);
343 
344 	/* Install the object */
345 
346 	node->object = object;
347 	return_ACPI_STATUS(status);
348 }
349 
350 /*******************************************************************************
351  *
352  * FUNCTION:    acpi_ds_method_data_get_value
353  *
354  * PARAMETERS:  type                - Either ACPI_REFCLASS_LOCAL or
355  *                                    ACPI_REFCLASS_ARG
356  *              index               - Which localVar or argument to get
357  *              walk_state          - Current walk state object
358  *              dest_desc           - Where Arg or Local value is returned
359  *
360  * RETURN:      Status
361  *
362  * DESCRIPTION: Retrieve value of selected Arg or Local for this method
363  *              Used only in acpi_ex_resolve_to_value().
364  *
365  ******************************************************************************/
366 
367 acpi_status
368 acpi_ds_method_data_get_value(u8 type,
369 			      u32 index,
370 			      struct acpi_walk_state *walk_state,
371 			      union acpi_operand_object **dest_desc)
372 {
373 	acpi_status status;
374 	struct acpi_namespace_node *node;
375 	union acpi_operand_object *object;
376 
377 	ACPI_FUNCTION_TRACE(ds_method_data_get_value);
378 
379 	/* Validate the object descriptor */
380 
381 	if (!dest_desc) {
382 		ACPI_ERROR((AE_INFO, "Null object descriptor pointer"));
383 		return_ACPI_STATUS(AE_BAD_PARAMETER);
384 	}
385 
386 	/* Get the namespace node for the arg/local */
387 
388 	status = acpi_ds_method_data_get_node(type, index, walk_state, &node);
389 	if (ACPI_FAILURE(status)) {
390 		return_ACPI_STATUS(status);
391 	}
392 
393 	/* Get the object from the node */
394 
395 	object = node->object;
396 
397 	/* Examine the returned object, it must be valid. */
398 
399 	if (!object) {
400 		/*
401 		 * Index points to uninitialized object.
402 		 * This means that either 1) The expected argument was
403 		 * not passed to the method, or 2) A local variable
404 		 * was referenced by the method (via the ASL)
405 		 * before it was initialized. Either case is an error.
406 		 */
407 
408 		/* If slack enabled, init the local_x/arg_x to an Integer of value zero */
409 
410 		if (acpi_gbl_enable_interpreter_slack) {
411 			object = acpi_ut_create_integer_object((u64) 0);
412 			if (!object) {
413 				return_ACPI_STATUS(AE_NO_MEMORY);
414 			}
415 
416 			node->object = object;
417 		}
418 
419 		/* Otherwise, return the error */
420 
421 		else
422 			switch (type) {
423 			case ACPI_REFCLASS_ARG:
424 
425 				ACPI_ERROR((AE_INFO,
426 					    "Uninitialized Arg[%u] at node %p",
427 					    index, node));
428 
429 				return_ACPI_STATUS(AE_AML_UNINITIALIZED_ARG);
430 
431 			case ACPI_REFCLASS_LOCAL:
432 				/*
433 				 * No error message for this case, will be trapped again later to
434 				 * detect and ignore cases of Store(local_x,local_x)
435 				 */
436 				return_ACPI_STATUS(AE_AML_UNINITIALIZED_LOCAL);
437 
438 			default:
439 
440 				ACPI_ERROR((AE_INFO,
441 					    "Not a Arg/Local opcode: 0x%X",
442 					    type));
443 				return_ACPI_STATUS(AE_AML_INTERNAL);
444 			}
445 	}
446 
447 	/*
448 	 * The Index points to an initialized and valid object.
449 	 * Return an additional reference to the object
450 	 */
451 	*dest_desc = object;
452 	acpi_ut_add_reference(object);
453 
454 	return_ACPI_STATUS(AE_OK);
455 }
456 
457 /*******************************************************************************
458  *
459  * FUNCTION:    acpi_ds_method_data_delete_value
460  *
461  * PARAMETERS:  type                - Either ACPI_REFCLASS_LOCAL or
462  *                                    ACPI_REFCLASS_ARG
463  *              index               - Which localVar or argument to delete
464  *              walk_state          - Current walk state object
465  *
466  * RETURN:      None
467  *
468  * DESCRIPTION: Delete the entry at Opcode:Index. Inserts
469  *              a null into the stack slot after the object is deleted.
470  *
471  ******************************************************************************/
472 
473 static void
474 acpi_ds_method_data_delete_value(u8 type,
475 				 u32 index, struct acpi_walk_state *walk_state)
476 {
477 	acpi_status status;
478 	struct acpi_namespace_node *node;
479 	union acpi_operand_object *object;
480 
481 	ACPI_FUNCTION_TRACE(ds_method_data_delete_value);
482 
483 	/* Get the namespace node for the arg/local */
484 
485 	status = acpi_ds_method_data_get_node(type, index, walk_state, &node);
486 	if (ACPI_FAILURE(status)) {
487 		return_VOID;
488 	}
489 
490 	/* Get the associated object */
491 
492 	object = acpi_ns_get_attached_object(node);
493 
494 	/*
495 	 * Undefine the Arg or Local by setting its descriptor
496 	 * pointer to NULL. Locals/Args can contain both
497 	 * ACPI_OPERAND_OBJECTS and ACPI_NAMESPACE_NODEs
498 	 */
499 	node->object = NULL;
500 
501 	if ((object) &&
502 	    (ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_OPERAND)) {
503 		/*
504 		 * There is a valid object.
505 		 * Decrement the reference count by one to balance the
506 		 * increment when the object was stored.
507 		 */
508 		acpi_ut_remove_reference(object);
509 	}
510 
511 	return_VOID;
512 }
513 
514 /*******************************************************************************
515  *
516  * FUNCTION:    acpi_ds_store_object_to_local
517  *
518  * PARAMETERS:  type                - Either ACPI_REFCLASS_LOCAL or
519  *                                    ACPI_REFCLASS_ARG
520  *              index               - Which Local or Arg to set
521  *              obj_desc            - Value to be stored
522  *              walk_state          - Current walk state
523  *
524  * RETURN:      Status
525  *
526  * DESCRIPTION: Store a value in an Arg or Local. The obj_desc is installed
527  *              as the new value for the Arg or Local and the reference count
528  *              for obj_desc is incremented.
529  *
530  ******************************************************************************/
531 
532 acpi_status
533 acpi_ds_store_object_to_local(u8 type,
534 			      u32 index,
535 			      union acpi_operand_object *obj_desc,
536 			      struct acpi_walk_state *walk_state)
537 {
538 	acpi_status status;
539 	struct acpi_namespace_node *node;
540 	union acpi_operand_object *current_obj_desc;
541 	union acpi_operand_object *new_obj_desc;
542 
543 	ACPI_FUNCTION_TRACE(ds_store_object_to_local);
544 	ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Type=%2.2X Index=%u Obj=%p\n",
545 			  type, index, obj_desc));
546 
547 	/* Parameter validation */
548 
549 	if (!obj_desc) {
550 		return_ACPI_STATUS(AE_BAD_PARAMETER);
551 	}
552 
553 	/* Get the namespace node for the arg/local */
554 
555 	status = acpi_ds_method_data_get_node(type, index, walk_state, &node);
556 	if (ACPI_FAILURE(status)) {
557 		return_ACPI_STATUS(status);
558 	}
559 
560 	current_obj_desc = acpi_ns_get_attached_object(node);
561 	if (current_obj_desc == obj_desc) {
562 		ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p already installed!\n",
563 				  obj_desc));
564 		return_ACPI_STATUS(status);
565 	}
566 
567 	/*
568 	 * If the reference count on the object is more than one, we must
569 	 * take a copy of the object before we store. A reference count
570 	 * of exactly 1 means that the object was just created during the
571 	 * evaluation of an expression, and we can safely use it since it
572 	 * is not used anywhere else.
573 	 */
574 	new_obj_desc = obj_desc;
575 	if (obj_desc->common.reference_count > 1) {
576 		status =
577 		    acpi_ut_copy_iobject_to_iobject(obj_desc, &new_obj_desc,
578 						    walk_state);
579 		if (ACPI_FAILURE(status)) {
580 			return_ACPI_STATUS(status);
581 		}
582 	}
583 
584 	/*
585 	 * If there is an object already in this slot, we either
586 	 * have to delete it, or if this is an argument and there
587 	 * is an object reference stored there, we have to do
588 	 * an indirect store!
589 	 */
590 	if (current_obj_desc) {
591 		/*
592 		 * Check for an indirect store if an argument
593 		 * contains an object reference (stored as an Node).
594 		 * We don't allow this automatic dereferencing for
595 		 * locals, since a store to a local should overwrite
596 		 * anything there, including an object reference.
597 		 *
598 		 * If both Arg0 and Local0 contain ref_of (Local4):
599 		 *
600 		 * Store (1, Arg0)             - Causes indirect store to local4
601 		 * Store (1, Local0)           - Stores 1 in local0, overwriting
602 		 *                                  the reference to local4
603 		 * Store (1, de_refof (Local0)) - Causes indirect store to local4
604 		 *
605 		 * Weird, but true.
606 		 */
607 		if (type == ACPI_REFCLASS_ARG) {
608 			/*
609 			 * If we have a valid reference object that came from ref_of(),
610 			 * do the indirect store
611 			 */
612 			if ((ACPI_GET_DESCRIPTOR_TYPE(current_obj_desc) ==
613 			     ACPI_DESC_TYPE_OPERAND)
614 			    && (current_obj_desc->common.type ==
615 				ACPI_TYPE_LOCAL_REFERENCE)
616 			    && (current_obj_desc->reference.class ==
617 				ACPI_REFCLASS_REFOF)) {
618 				ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
619 						  "Arg (%p) is an ObjRef(Node), storing in node %p\n",
620 						  new_obj_desc,
621 						  current_obj_desc));
622 
623 				/*
624 				 * Store this object to the Node (perform the indirect store)
625 				 * NOTE: No implicit conversion is performed, as per the ACPI
626 				 * specification rules on storing to Locals/Args.
627 				 */
628 				status =
629 				    acpi_ex_store_object_to_node(new_obj_desc,
630 								 current_obj_desc->
631 								 reference.
632 								 object,
633 								 walk_state,
634 								 ACPI_NO_IMPLICIT_CONVERSION);
635 
636 				/* Remove local reference if we copied the object above */
637 
638 				if (new_obj_desc != obj_desc) {
639 					acpi_ut_remove_reference(new_obj_desc);
640 				}
641 				return_ACPI_STATUS(status);
642 			}
643 		}
644 
645 		/* Delete the existing object before storing the new one */
646 
647 		acpi_ds_method_data_delete_value(type, index, walk_state);
648 	}
649 
650 	/*
651 	 * Install the Obj descriptor (*new_obj_desc) into
652 	 * the descriptor for the Arg or Local.
653 	 * (increments the object reference count by one)
654 	 */
655 	status =
656 	    acpi_ds_method_data_set_value(type, index, new_obj_desc,
657 					  walk_state);
658 
659 	/* Remove local reference if we copied the object above */
660 
661 	if (new_obj_desc != obj_desc) {
662 		acpi_ut_remove_reference(new_obj_desc);
663 	}
664 
665 	return_ACPI_STATUS(status);
666 }
667 
668 #ifdef ACPI_OBSOLETE_FUNCTIONS
669 /*******************************************************************************
670  *
671  * FUNCTION:    acpi_ds_method_data_get_type
672  *
673  * PARAMETERS:  opcode              - Either AML_LOCAL_OP or AML_ARG_OP
674  *              index               - Which Local or Arg whose type to get
675  *              walk_state          - Current walk state object
676  *
677  * RETURN:      Data type of current value of the selected Arg or Local
678  *
679  * DESCRIPTION: Get the type of the object stored in the Local or Arg
680  *
681  ******************************************************************************/
682 
683 acpi_object_type
684 acpi_ds_method_data_get_type(u16 opcode,
685 			     u32 index, struct acpi_walk_state *walk_state)
686 {
687 	acpi_status status;
688 	struct acpi_namespace_node *node;
689 	union acpi_operand_object *object;
690 
691 	ACPI_FUNCTION_TRACE(ds_method_data_get_type);
692 
693 	/* Get the namespace node for the arg/local */
694 
695 	status = acpi_ds_method_data_get_node(opcode, index, walk_state, &node);
696 	if (ACPI_FAILURE(status)) {
697 		return_VALUE((ACPI_TYPE_NOT_FOUND));
698 	}
699 
700 	/* Get the object */
701 
702 	object = acpi_ns_get_attached_object(node);
703 	if (!object) {
704 
705 		/* Uninitialized local/arg, return TYPE_ANY */
706 
707 		return_VALUE(ACPI_TYPE_ANY);
708 	}
709 
710 	/* Get the object type */
711 
712 	return_VALUE(object->type);
713 }
714 #endif
715