Merge branch 'for-linus' of git://git390.osdl.marist.edu/pub/scm/linux-2.6
[linux-2.6] / drivers / acpi / acpica / exresolv.c
1
2 /******************************************************************************
3  *
4  * Module Name: exresolv - AML Interpreter object resolution
5  *
6  *****************************************************************************/
7
8 /*
9  * Copyright (C) 2000 - 2008, Intel Corp.
10  * All rights reserved.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions, and the following disclaimer,
17  *    without modification.
18  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
19  *    substantially similar to the "NO WARRANTY" disclaimer below
20  *    ("Disclaimer") and any redistribution must be conditioned upon
21  *    including a substantially similar Disclaimer requirement for further
22  *    binary redistribution.
23  * 3. Neither the names of the above-listed copyright holders nor the names
24  *    of any contributors may be used to endorse or promote products derived
25  *    from this software without specific prior written permission.
26  *
27  * Alternatively, this software may be distributed under the terms of the
28  * GNU General Public License ("GPL") version 2 as published by the Free
29  * Software Foundation.
30  *
31  * NO WARRANTY
32  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
33  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
34  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
35  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
36  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
37  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
38  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
39  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
40  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
41  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
42  * POSSIBILITY OF SUCH DAMAGES.
43  */
44
45 #include <acpi/acpi.h>
46 #include "accommon.h"
47 #include "amlcode.h"
48 #include "acdispat.h"
49 #include "acinterp.h"
50 #include "acnamesp.h"
51
52 #define _COMPONENT          ACPI_EXECUTER
53 ACPI_MODULE_NAME("exresolv")
54
55 /* Local prototypes */
56 static acpi_status
57 acpi_ex_resolve_object_to_value(union acpi_operand_object **stack_ptr,
58                                 struct acpi_walk_state *walk_state);
59
60 /*******************************************************************************
61  *
62  * FUNCTION:    acpi_ex_resolve_to_value
63  *
64  * PARAMETERS:  **stack_ptr         - Points to entry on obj_stack, which can
65  *                                    be either an (union acpi_operand_object *)
66  *                                    or an acpi_handle.
67  *              walk_state          - Current method state
68  *
69  * RETURN:      Status
70  *
71  * DESCRIPTION: Convert Reference objects to values
72  *
73  ******************************************************************************/
74
75 acpi_status
76 acpi_ex_resolve_to_value(union acpi_operand_object **stack_ptr,
77                          struct acpi_walk_state *walk_state)
78 {
79         acpi_status status;
80
81         ACPI_FUNCTION_TRACE_PTR(ex_resolve_to_value, stack_ptr);
82
83         if (!stack_ptr || !*stack_ptr) {
84                 ACPI_ERROR((AE_INFO, "Internal - null pointer"));
85                 return_ACPI_STATUS(AE_AML_NO_OPERAND);
86         }
87
88         /*
89          * The entity pointed to by the stack_ptr can be either
90          * 1) A valid union acpi_operand_object, or
91          * 2) A struct acpi_namespace_node (named_obj)
92          */
93         if (ACPI_GET_DESCRIPTOR_TYPE(*stack_ptr) == ACPI_DESC_TYPE_OPERAND) {
94                 status = acpi_ex_resolve_object_to_value(stack_ptr, walk_state);
95                 if (ACPI_FAILURE(status)) {
96                         return_ACPI_STATUS(status);
97                 }
98
99                 if (!*stack_ptr) {
100                         ACPI_ERROR((AE_INFO, "Internal - null pointer"));
101                         return_ACPI_STATUS(AE_AML_NO_OPERAND);
102                 }
103         }
104
105         /*
106          * Object on the stack may have changed if acpi_ex_resolve_object_to_value()
107          * was called (i.e., we can't use an _else_ here.)
108          */
109         if (ACPI_GET_DESCRIPTOR_TYPE(*stack_ptr) == ACPI_DESC_TYPE_NAMED) {
110                 status =
111                     acpi_ex_resolve_node_to_value(ACPI_CAST_INDIRECT_PTR
112                                                   (struct acpi_namespace_node,
113                                                    stack_ptr), walk_state);
114                 if (ACPI_FAILURE(status)) {
115                         return_ACPI_STATUS(status);
116                 }
117         }
118
119         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Resolved object %p\n", *stack_ptr));
120         return_ACPI_STATUS(AE_OK);
121 }
122
123 /*******************************************************************************
124  *
125  * FUNCTION:    acpi_ex_resolve_object_to_value
126  *
127  * PARAMETERS:  stack_ptr       - Pointer to an internal object
128  *              walk_state      - Current method state
129  *
130  * RETURN:      Status
131  *
132  * DESCRIPTION: Retrieve the value from an internal object. The Reference type
133  *              uses the associated AML opcode to determine the value.
134  *
135  ******************************************************************************/
136
137 static acpi_status
138 acpi_ex_resolve_object_to_value(union acpi_operand_object **stack_ptr,
139                                 struct acpi_walk_state *walk_state)
140 {
141         acpi_status status = AE_OK;
142         union acpi_operand_object *stack_desc;
143         union acpi_operand_object *obj_desc = NULL;
144         u8 ref_type;
145
146         ACPI_FUNCTION_TRACE(ex_resolve_object_to_value);
147
148         stack_desc = *stack_ptr;
149
150         /* This is a union acpi_operand_object    */
151
152         switch (ACPI_GET_OBJECT_TYPE(stack_desc)) {
153         case ACPI_TYPE_LOCAL_REFERENCE:
154
155                 ref_type = stack_desc->reference.class;
156
157                 switch (ref_type) {
158                 case ACPI_REFCLASS_LOCAL:
159                 case ACPI_REFCLASS_ARG:
160
161                         /*
162                          * Get the local from the method's state info
163                          * Note: this increments the local's object reference count
164                          */
165                         status = acpi_ds_method_data_get_value(ref_type,
166                                                                stack_desc->
167                                                                reference.value,
168                                                                walk_state,
169                                                                &obj_desc);
170                         if (ACPI_FAILURE(status)) {
171                                 return_ACPI_STATUS(status);
172                         }
173
174                         ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
175                                           "[Arg/Local %X] ValueObj is %p\n",
176                                           stack_desc->reference.value,
177                                           obj_desc));
178
179                         /*
180                          * Now we can delete the original Reference Object and
181                          * replace it with the resolved value
182                          */
183                         acpi_ut_remove_reference(stack_desc);
184                         *stack_ptr = obj_desc;
185                         break;
186
187                 case ACPI_REFCLASS_INDEX:
188
189                         switch (stack_desc->reference.target_type) {
190                         case ACPI_TYPE_BUFFER_FIELD:
191
192                                 /* Just return - do not dereference */
193                                 break;
194
195                         case ACPI_TYPE_PACKAGE:
196
197                                 /* If method call or copy_object - do not dereference */
198
199                                 if ((walk_state->opcode ==
200                                      AML_INT_METHODCALL_OP)
201                                     || (walk_state->opcode == AML_COPY_OP)) {
202                                         break;
203                                 }
204
205                                 /* Otherwise, dereference the package_index to a package element */
206
207                                 obj_desc = *stack_desc->reference.where;
208                                 if (obj_desc) {
209                                         /*
210                                          * Valid object descriptor, copy pointer to return value
211                                          * (i.e., dereference the package index)
212                                          * Delete the ref object, increment the returned object
213                                          */
214                                         acpi_ut_remove_reference(stack_desc);
215                                         acpi_ut_add_reference(obj_desc);
216                                         *stack_ptr = obj_desc;
217                                 } else {
218                                         /*
219                                          * A NULL object descriptor means an uninitialized element of
220                                          * the package, can't dereference it
221                                          */
222                                         ACPI_ERROR((AE_INFO,
223                                                     "Attempt to dereference an Index to NULL package element Idx=%p",
224                                                     stack_desc));
225                                         status = AE_AML_UNINITIALIZED_ELEMENT;
226                                 }
227                                 break;
228
229                         default:
230
231                                 /* Invalid reference object */
232
233                                 ACPI_ERROR((AE_INFO,
234                                             "Unknown TargetType %X in Index/Reference object %p",
235                                             stack_desc->reference.target_type,
236                                             stack_desc));
237                                 status = AE_AML_INTERNAL;
238                                 break;
239                         }
240                         break;
241
242                 case ACPI_REFCLASS_REFOF:
243                 case ACPI_REFCLASS_DEBUG:
244                 case ACPI_REFCLASS_TABLE:
245
246                         /* Just leave the object as-is, do not dereference */
247
248                         break;
249
250                 case ACPI_REFCLASS_NAME:        /* Reference to a named object */
251
252                         /* Dereference the name */
253
254                         if ((stack_desc->reference.node->type ==
255                              ACPI_TYPE_DEVICE)
256                             || (stack_desc->reference.node->type ==
257                                 ACPI_TYPE_THERMAL)) {
258
259                                 /* These node types do not have 'real' subobjects */
260
261                                 *stack_ptr = (void *)stack_desc->reference.node;
262                         } else {
263                                 /* Get the object pointed to by the namespace node */
264
265                                 *stack_ptr =
266                                     (stack_desc->reference.node)->object;
267                                 acpi_ut_add_reference(*stack_ptr);
268                         }
269
270                         acpi_ut_remove_reference(stack_desc);
271                         break;
272
273                 default:
274
275                         ACPI_ERROR((AE_INFO,
276                                     "Unknown Reference type %X in %p", ref_type,
277                                     stack_desc));
278                         status = AE_AML_INTERNAL;
279                         break;
280                 }
281                 break;
282
283         case ACPI_TYPE_BUFFER:
284
285                 status = acpi_ds_get_buffer_arguments(stack_desc);
286                 break;
287
288         case ACPI_TYPE_PACKAGE:
289
290                 status = acpi_ds_get_package_arguments(stack_desc);
291                 break;
292
293         case ACPI_TYPE_BUFFER_FIELD:
294         case ACPI_TYPE_LOCAL_REGION_FIELD:
295         case ACPI_TYPE_LOCAL_BANK_FIELD:
296         case ACPI_TYPE_LOCAL_INDEX_FIELD:
297
298                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
299                                   "FieldRead SourceDesc=%p Type=%X\n",
300                                   stack_desc,
301                                   ACPI_GET_OBJECT_TYPE(stack_desc)));
302
303                 status =
304                     acpi_ex_read_data_from_field(walk_state, stack_desc,
305                                                  &obj_desc);
306
307                 /* Remove a reference to the original operand, then override */
308
309                 acpi_ut_remove_reference(*stack_ptr);
310                 *stack_ptr = (void *)obj_desc;
311                 break;
312
313         default:
314                 break;
315         }
316
317         return_ACPI_STATUS(status);
318 }
319
320 /*******************************************************************************
321  *
322  * FUNCTION:    acpi_ex_resolve_multiple
323  *
324  * PARAMETERS:  walk_state          - Current state (contains AML opcode)
325  *              Operand             - Starting point for resolution
326  *              return_type         - Where the object type is returned
327  *              return_desc         - Where the resolved object is returned
328  *
329  * RETURN:      Status
330  *
331  * DESCRIPTION: Return the base object and type.  Traverse a reference list if
332  *              necessary to get to the base object.
333  *
334  ******************************************************************************/
335
336 acpi_status
337 acpi_ex_resolve_multiple(struct acpi_walk_state *walk_state,
338                          union acpi_operand_object *operand,
339                          acpi_object_type * return_type,
340                          union acpi_operand_object **return_desc)
341 {
342         union acpi_operand_object *obj_desc = (void *)operand;
343         struct acpi_namespace_node *node;
344         acpi_object_type type;
345         acpi_status status;
346
347         ACPI_FUNCTION_TRACE(acpi_ex_resolve_multiple);
348
349         /* Operand can be either a namespace node or an operand descriptor */
350
351         switch (ACPI_GET_DESCRIPTOR_TYPE(obj_desc)) {
352         case ACPI_DESC_TYPE_OPERAND:
353                 type = obj_desc->common.type;
354                 break;
355
356         case ACPI_DESC_TYPE_NAMED:
357                 type = ((struct acpi_namespace_node *)obj_desc)->type;
358                 obj_desc =
359                     acpi_ns_get_attached_object((struct acpi_namespace_node *)
360                                                 obj_desc);
361
362                 /* If we had an Alias node, use the attached object for type info */
363
364                 if (type == ACPI_TYPE_LOCAL_ALIAS) {
365                         type = ((struct acpi_namespace_node *)obj_desc)->type;
366                         obj_desc =
367                             acpi_ns_get_attached_object((struct
368                                                          acpi_namespace_node *)
369                                                         obj_desc);
370                 }
371                 break;
372
373         default:
374                 return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
375         }
376
377         /* If type is anything other than a reference, we are done */
378
379         if (type != ACPI_TYPE_LOCAL_REFERENCE) {
380                 goto exit;
381         }
382
383         /*
384          * For reference objects created via the ref_of, Index, or Load/load_table
385          * operators, we need to get to the base object (as per the ACPI
386          * specification of the object_type and size_of operators). This means
387          * traversing the list of possibly many nested references.
388          */
389         while (ACPI_GET_OBJECT_TYPE(obj_desc) == ACPI_TYPE_LOCAL_REFERENCE) {
390                 switch (obj_desc->reference.class) {
391                 case ACPI_REFCLASS_REFOF:
392                 case ACPI_REFCLASS_NAME:
393
394                         /* Dereference the reference pointer */
395
396                         if (obj_desc->reference.class == ACPI_REFCLASS_REFOF) {
397                                 node = obj_desc->reference.object;
398                         } else {        /* AML_INT_NAMEPATH_OP */
399
400                                 node = obj_desc->reference.node;
401                         }
402
403                         /* All "References" point to a NS node */
404
405                         if (ACPI_GET_DESCRIPTOR_TYPE(node) !=
406                             ACPI_DESC_TYPE_NAMED) {
407                                 ACPI_ERROR((AE_INFO, "Not a NS node %p [%s]",
408                                             node,
409                                             acpi_ut_get_descriptor_name(node)));
410                                 return_ACPI_STATUS(AE_AML_INTERNAL);
411                         }
412
413                         /* Get the attached object */
414
415                         obj_desc = acpi_ns_get_attached_object(node);
416                         if (!obj_desc) {
417
418                                 /* No object, use the NS node type */
419
420                                 type = acpi_ns_get_type(node);
421                                 goto exit;
422                         }
423
424                         /* Check for circular references */
425
426                         if (obj_desc == operand) {
427                                 return_ACPI_STATUS(AE_AML_CIRCULAR_REFERENCE);
428                         }
429                         break;
430
431                 case ACPI_REFCLASS_INDEX:
432
433                         /* Get the type of this reference (index into another object) */
434
435                         type = obj_desc->reference.target_type;
436                         if (type != ACPI_TYPE_PACKAGE) {
437                                 goto exit;
438                         }
439
440                         /*
441                          * The main object is a package, we want to get the type
442                          * of the individual package element that is referenced by
443                          * the index.
444                          *
445                          * This could of course in turn be another reference object.
446                          */
447                         obj_desc = *(obj_desc->reference.where);
448                         if (!obj_desc) {
449
450                                 /* NULL package elements are allowed */
451
452                                 type = 0;       /* Uninitialized */
453                                 goto exit;
454                         }
455                         break;
456
457                 case ACPI_REFCLASS_TABLE:
458
459                         type = ACPI_TYPE_DDB_HANDLE;
460                         goto exit;
461
462                 case ACPI_REFCLASS_LOCAL:
463                 case ACPI_REFCLASS_ARG:
464
465                         if (return_desc) {
466                                 status =
467                                     acpi_ds_method_data_get_value(obj_desc->
468                                                                   reference.
469                                                                   class,
470                                                                   obj_desc->
471                                                                   reference.
472                                                                   value,
473                                                                   walk_state,
474                                                                   &obj_desc);
475                                 if (ACPI_FAILURE(status)) {
476                                         return_ACPI_STATUS(status);
477                                 }
478                                 acpi_ut_remove_reference(obj_desc);
479                         } else {
480                                 status =
481                                     acpi_ds_method_data_get_node(obj_desc->
482                                                                  reference.
483                                                                  class,
484                                                                  obj_desc->
485                                                                  reference.
486                                                                  value,
487                                                                  walk_state,
488                                                                  &node);
489                                 if (ACPI_FAILURE(status)) {
490                                         return_ACPI_STATUS(status);
491                                 }
492
493                                 obj_desc = acpi_ns_get_attached_object(node);
494                                 if (!obj_desc) {
495                                         type = ACPI_TYPE_ANY;
496                                         goto exit;
497                                 }
498                         }
499                         break;
500
501                 case ACPI_REFCLASS_DEBUG:
502
503                         /* The Debug Object is of type "DebugObject" */
504
505                         type = ACPI_TYPE_DEBUG_OBJECT;
506                         goto exit;
507
508                 default:
509
510                         ACPI_ERROR((AE_INFO,
511                                     "Unknown Reference Class %2.2X",
512                                     obj_desc->reference.class));
513                         return_ACPI_STATUS(AE_AML_INTERNAL);
514                 }
515         }
516
517         /*
518          * Now we are guaranteed to have an object that has not been created
519          * via the ref_of or Index operators.
520          */
521         type = ACPI_GET_OBJECT_TYPE(obj_desc);
522
523       exit:
524         /* Convert internal types to external types */
525
526         switch (type) {
527         case ACPI_TYPE_LOCAL_REGION_FIELD:
528         case ACPI_TYPE_LOCAL_BANK_FIELD:
529         case ACPI_TYPE_LOCAL_INDEX_FIELD:
530
531                 type = ACPI_TYPE_FIELD_UNIT;
532                 break;
533
534         case ACPI_TYPE_LOCAL_SCOPE:
535
536                 /* Per ACPI Specification, Scope is untyped */
537
538                 type = ACPI_TYPE_ANY;
539                 break;
540
541         default:
542                 /* No change to Type required */
543                 break;
544         }
545
546         *return_type = type;
547         if (return_desc) {
548                 *return_desc = obj_desc;
549         }
550         return_ACPI_STATUS(AE_OK);
551 }