Merge branch 'next-s3c' of git://aeryn.fluff.org.uk/bjdooks/linux into devel
[linux-2.6] / drivers / acpi / acpica / nsxfeval.c
1 /*******************************************************************************
2  *
3  * Module Name: nsxfeval - Public interfaces to the ACPI subsystem
4  *                         ACPI Object evaluation interfaces
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 "acnamesp.h"
48 #include "acinterp.h"
49
50 #define _COMPONENT          ACPI_NAMESPACE
51 ACPI_MODULE_NAME("nsxfeval")
52
53 /* Local prototypes */
54 static void acpi_ns_resolve_references(struct acpi_evaluate_info *info);
55
56 /*******************************************************************************
57  *
58  * FUNCTION:    acpi_evaluate_object_typed
59  *
60  * PARAMETERS:  Handle              - Object handle (optional)
61  *              Pathname            - Object pathname (optional)
62  *              external_params     - List of parameters to pass to method,
63  *                                    terminated by NULL.  May be NULL
64  *                                    if no parameters are being passed.
65  *              return_buffer       - Where to put method's return value (if
66  *                                    any).  If NULL, no value is returned.
67  *              return_type         - Expected type of return object
68  *
69  * RETURN:      Status
70  *
71  * DESCRIPTION: Find and evaluate the given object, passing the given
72  *              parameters if necessary.  One of "Handle" or "Pathname" must
73  *              be valid (non-null)
74  *
75  ******************************************************************************/
76
77 acpi_status
78 acpi_evaluate_object_typed(acpi_handle handle,
79                            acpi_string pathname,
80                            struct acpi_object_list *external_params,
81                            struct acpi_buffer *return_buffer,
82                            acpi_object_type return_type)
83 {
84         acpi_status status;
85         u8 must_free = FALSE;
86
87         ACPI_FUNCTION_TRACE(acpi_evaluate_object_typed);
88
89         /* Return buffer must be valid */
90
91         if (!return_buffer) {
92                 return_ACPI_STATUS(AE_BAD_PARAMETER);
93         }
94
95         if (return_buffer->length == ACPI_ALLOCATE_BUFFER) {
96                 must_free = TRUE;
97         }
98
99         /* Evaluate the object */
100
101         status =
102             acpi_evaluate_object(handle, pathname, external_params,
103                                  return_buffer);
104         if (ACPI_FAILURE(status)) {
105                 return_ACPI_STATUS(status);
106         }
107
108         /* Type ANY means "don't care" */
109
110         if (return_type == ACPI_TYPE_ANY) {
111                 return_ACPI_STATUS(AE_OK);
112         }
113
114         if (return_buffer->length == 0) {
115
116                 /* Error because caller specifically asked for a return value */
117
118                 ACPI_ERROR((AE_INFO, "No return value"));
119                 return_ACPI_STATUS(AE_NULL_OBJECT);
120         }
121
122         /* Examine the object type returned from evaluate_object */
123
124         if (((union acpi_object *)return_buffer->pointer)->type == return_type) {
125                 return_ACPI_STATUS(AE_OK);
126         }
127
128         /* Return object type does not match requested type */
129
130         ACPI_ERROR((AE_INFO,
131                     "Incorrect return type [%s] requested [%s]",
132                     acpi_ut_get_type_name(((union acpi_object *)return_buffer->
133                                            pointer)->type),
134                     acpi_ut_get_type_name(return_type)));
135
136         if (must_free) {
137
138                 /* Caller used ACPI_ALLOCATE_BUFFER, free the return buffer */
139
140                 ACPI_FREE(return_buffer->pointer);
141                 return_buffer->pointer = NULL;
142         }
143
144         return_buffer->length = 0;
145         return_ACPI_STATUS(AE_TYPE);
146 }
147
148 ACPI_EXPORT_SYMBOL(acpi_evaluate_object_typed)
149
150 /*******************************************************************************
151  *
152  * FUNCTION:    acpi_evaluate_object
153  *
154  * PARAMETERS:  Handle              - Object handle (optional)
155  *              Pathname            - Object pathname (optional)
156  *              external_params     - List of parameters to pass to method,
157  *                                    terminated by NULL.  May be NULL
158  *                                    if no parameters are being passed.
159  *              return_buffer       - Where to put method's return value (if
160  *                                    any).  If NULL, no value is returned.
161  *
162  * RETURN:      Status
163  *
164  * DESCRIPTION: Find and evaluate the given object, passing the given
165  *              parameters if necessary.  One of "Handle" or "Pathname" must
166  *              be valid (non-null)
167  *
168  ******************************************************************************/
169 acpi_status
170 acpi_evaluate_object(acpi_handle handle,
171                      acpi_string pathname,
172                      struct acpi_object_list *external_params,
173                      struct acpi_buffer *return_buffer)
174 {
175         acpi_status status;
176         struct acpi_evaluate_info *info;
177         acpi_size buffer_space_needed;
178         u32 i;
179
180         ACPI_FUNCTION_TRACE(acpi_evaluate_object);
181
182         /* Allocate and initialize the evaluation information block */
183
184         info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
185         if (!info) {
186                 return_ACPI_STATUS(AE_NO_MEMORY);
187         }
188
189         info->pathname = pathname;
190
191         /* Convert and validate the device handle */
192
193         info->prefix_node = acpi_ns_map_handle_to_node(handle);
194         if (!info->prefix_node) {
195                 status = AE_BAD_PARAMETER;
196                 goto cleanup;
197         }
198
199         /*
200          * If there are parameters to be passed to a control method, the external
201          * objects must all be converted to internal objects
202          */
203         if (external_params && external_params->count) {
204                 /*
205                  * Allocate a new parameter block for the internal objects
206                  * Add 1 to count to allow for null terminated internal list
207                  */
208                 info->parameters = ACPI_ALLOCATE_ZEROED(((acpi_size)
209                                                          external_params->
210                                                          count +
211                                                          1) * sizeof(void *));
212                 if (!info->parameters) {
213                         status = AE_NO_MEMORY;
214                         goto cleanup;
215                 }
216
217                 /* Convert each external object in the list to an internal object */
218
219                 for (i = 0; i < external_params->count; i++) {
220                         status =
221                             acpi_ut_copy_eobject_to_iobject(&external_params->
222                                                             pointer[i],
223                                                             &info->
224                                                             parameters[i]);
225                         if (ACPI_FAILURE(status)) {
226                                 goto cleanup;
227                         }
228                 }
229                 info->parameters[external_params->count] = NULL;
230         }
231
232         /*
233          * Three major cases:
234          * 1) Fully qualified pathname
235          * 2) No handle, not fully qualified pathname (error)
236          * 3) Valid handle
237          */
238         if ((pathname) && (acpi_ns_valid_root_prefix(pathname[0]))) {
239
240                 /* The path is fully qualified, just evaluate by name */
241
242                 info->prefix_node = NULL;
243                 status = acpi_ns_evaluate(info);
244         } else if (!handle) {
245                 /*
246                  * A handle is optional iff a fully qualified pathname is specified.
247                  * Since we've already handled fully qualified names above, this is
248                  * an error
249                  */
250                 if (!pathname) {
251                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
252                                           "Both Handle and Pathname are NULL"));
253                 } else {
254                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
255                                           "Null Handle with relative pathname [%s]",
256                                           pathname));
257                 }
258
259                 status = AE_BAD_PARAMETER;
260         } else {
261                 /* We have a namespace a node and a possible relative path */
262
263                 status = acpi_ns_evaluate(info);
264         }
265
266         /*
267          * If we are expecting a return value, and all went well above,
268          * copy the return value to an external object.
269          */
270         if (return_buffer) {
271                 if (!info->return_object) {
272                         return_buffer->length = 0;
273                 } else {
274                         if (ACPI_GET_DESCRIPTOR_TYPE(info->return_object) ==
275                             ACPI_DESC_TYPE_NAMED) {
276                                 /*
277                                  * If we received a NS Node as a return object, this means that
278                                  * the object we are evaluating has nothing interesting to
279                                  * return (such as a mutex, etc.)  We return an error because
280                                  * these types are essentially unsupported by this interface.
281                                  * We don't check up front because this makes it easier to add
282                                  * support for various types at a later date if necessary.
283                                  */
284                                 status = AE_TYPE;
285                                 info->return_object = NULL;     /* No need to delete a NS Node */
286                                 return_buffer->length = 0;
287                         }
288
289                         if (ACPI_SUCCESS(status)) {
290
291                                 /* Dereference Index and ref_of references */
292
293                                 acpi_ns_resolve_references(info);
294
295                                 /* Get the size of the returned object */
296
297                                 status =
298                                     acpi_ut_get_object_size(info->return_object,
299                                                             &buffer_space_needed);
300                                 if (ACPI_SUCCESS(status)) {
301
302                                         /* Validate/Allocate/Clear caller buffer */
303
304                                         status =
305                                             acpi_ut_initialize_buffer
306                                             (return_buffer,
307                                              buffer_space_needed);
308                                         if (ACPI_FAILURE(status)) {
309                                                 /*
310                                                  * Caller's buffer is too small or a new one can't
311                                                  * be allocated
312                                                  */
313                                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
314                                                                   "Needed buffer size %X, %s\n",
315                                                                   (u32)
316                                                                   buffer_space_needed,
317                                                                   acpi_format_exception
318                                                                   (status)));
319                                         } else {
320                                                 /* We have enough space for the object, build it */
321
322                                                 status =
323                                                     acpi_ut_copy_iobject_to_eobject
324                                                     (info->return_object,
325                                                      return_buffer);
326                                         }
327                                 }
328                         }
329                 }
330         }
331
332         if (info->return_object) {
333                 /*
334                  * Delete the internal return object. NOTE: Interpreter must be
335                  * locked to avoid race condition.
336                  */
337                 acpi_ex_enter_interpreter();
338
339                 /* Remove one reference on the return object (should delete it) */
340
341                 acpi_ut_remove_reference(info->return_object);
342                 acpi_ex_exit_interpreter();
343         }
344
345       cleanup:
346
347         /* Free the input parameter list (if we created one) */
348
349         if (info->parameters) {
350
351                 /* Free the allocated parameter block */
352
353                 acpi_ut_delete_internal_object_list(info->parameters);
354         }
355
356         ACPI_FREE(info);
357         return_ACPI_STATUS(status);
358 }
359
360 ACPI_EXPORT_SYMBOL(acpi_evaluate_object)
361
362 /*******************************************************************************
363  *
364  * FUNCTION:    acpi_ns_resolve_references
365  *
366  * PARAMETERS:  Info                    - Evaluation info block
367  *
368  * RETURN:      Info->return_object is replaced with the dereferenced object
369  *
370  * DESCRIPTION: Dereference certain reference objects. Called before an
371  *              internal return object is converted to an external union acpi_object.
372  *
373  * Performs an automatic dereference of Index and ref_of reference objects.
374  * These reference objects are not supported by the union acpi_object, so this is a
375  * last resort effort to return something useful. Also, provides compatibility
376  * with other ACPI implementations.
377  *
378  * NOTE: does not handle references within returned package objects or nested
379  * references, but this support could be added later if found to be necessary.
380  *
381  ******************************************************************************/
382 static void acpi_ns_resolve_references(struct acpi_evaluate_info *info)
383 {
384         union acpi_operand_object *obj_desc = NULL;
385         struct acpi_namespace_node *node;
386
387         /* We are interested in reference objects only */
388
389         if ((info->return_object)->common.type != ACPI_TYPE_LOCAL_REFERENCE) {
390                 return;
391         }
392
393         /*
394          * Two types of references are supported - those created by Index and
395          * ref_of operators. A name reference (AML_NAMEPATH_OP) can be converted
396          * to an union acpi_object, so it is not dereferenced here. A ddb_handle
397          * (AML_LOAD_OP) cannot be dereferenced, nor can it be converted to
398          * an union acpi_object.
399          */
400         switch (info->return_object->reference.class) {
401         case ACPI_REFCLASS_INDEX:
402
403                 obj_desc = *(info->return_object->reference.where);
404                 break;
405
406         case ACPI_REFCLASS_REFOF:
407
408                 node = info->return_object->reference.object;
409                 if (node) {
410                         obj_desc = node->object;
411                 }
412                 break;
413
414         default:
415                 return;
416         }
417
418         /* Replace the existing reference object */
419
420         if (obj_desc) {
421                 acpi_ut_add_reference(obj_desc);
422                 acpi_ut_remove_reference(info->return_object);
423                 info->return_object = obj_desc;
424         }
425
426         return;
427 }
428
429 /*******************************************************************************
430  *
431  * FUNCTION:    acpi_walk_namespace
432  *
433  * PARAMETERS:  Type                - acpi_object_type to search for
434  *              start_object        - Handle in namespace where search begins
435  *              max_depth           - Depth to which search is to reach
436  *              user_function       - Called when an object of "Type" is found
437  *              Context             - Passed to user function
438  *              return_value        - Location where return value of
439  *                                    user_function is put if terminated early
440  *
441  * RETURNS      Return value from the user_function if terminated early.
442  *              Otherwise, returns NULL.
443  *
444  * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
445  *              starting (and ending) at the object specified by start_handle.
446  *              The user_function is called whenever an object that matches
447  *              the type parameter is found.  If the user function returns
448  *              a non-zero value, the search is terminated immediately and this
449  *              value is returned to the caller.
450  *
451  *              The point of this procedure is to provide a generic namespace
452  *              walk routine that can be called from multiple places to
453  *              provide multiple services;  the User Function can be tailored
454  *              to each task, whether it is a print function, a compare
455  *              function, etc.
456  *
457  ******************************************************************************/
458
459 acpi_status
460 acpi_walk_namespace(acpi_object_type type,
461                     acpi_handle start_object,
462                     u32 max_depth,
463                     acpi_walk_callback user_function,
464                     void *context, void **return_value)
465 {
466         acpi_status status;
467
468         ACPI_FUNCTION_TRACE(acpi_walk_namespace);
469
470         /* Parameter validation */
471
472         if ((type > ACPI_TYPE_LOCAL_MAX) || (!max_depth) || (!user_function)) {
473                 return_ACPI_STATUS(AE_BAD_PARAMETER);
474         }
475
476         /*
477          * Need to acquire the namespace reader lock to prevent interference
478          * with any concurrent table unloads (which causes the deletion of
479          * namespace objects). We cannot allow the deletion of a namespace node
480          * while the user function is using it. The exception to this are the
481          * nodes created and deleted during control method execution -- these
482          * nodes are marked as temporary nodes and are ignored by the namespace
483          * walk. Thus, control methods can be executed while holding the
484          * namespace deletion lock (and the user function can execute control
485          * methods.)
486          */
487         status = acpi_ut_acquire_read_lock(&acpi_gbl_namespace_rw_lock);
488         if (ACPI_FAILURE(status)) {
489                 return status;
490         }
491
492         /*
493          * Lock the namespace around the walk. The namespace will be
494          * unlocked/locked around each call to the user function - since the user
495          * function must be allowed to make ACPICA calls itself (for example, it
496          * will typically execute control methods during device enumeration.)
497          */
498         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
499         if (ACPI_FAILURE(status)) {
500                 goto unlock_and_exit;
501         }
502
503         status = acpi_ns_walk_namespace(type, start_object, max_depth,
504                                         ACPI_NS_WALK_UNLOCK, user_function,
505                                         context, return_value);
506
507         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
508
509       unlock_and_exit:
510         (void)acpi_ut_release_read_lock(&acpi_gbl_namespace_rw_lock);
511         return_ACPI_STATUS(status);
512 }
513
514 ACPI_EXPORT_SYMBOL(acpi_walk_namespace)
515
516 /*******************************************************************************
517  *
518  * FUNCTION:    acpi_ns_get_device_callback
519  *
520  * PARAMETERS:  Callback from acpi_get_device
521  *
522  * RETURN:      Status
523  *
524  * DESCRIPTION: Takes callbacks from walk_namespace and filters out all non-
525  *              present devices, or if they specified a HID, it filters based
526  *              on that.
527  *
528  ******************************************************************************/
529 static acpi_status
530 acpi_ns_get_device_callback(acpi_handle obj_handle,
531                             u32 nesting_level,
532                             void *context, void **return_value)
533 {
534         struct acpi_get_devices_info *info = context;
535         acpi_status status;
536         struct acpi_namespace_node *node;
537         u32 flags;
538         struct acpica_device_id hid;
539         struct acpi_compatible_id_list *cid;
540         u32 i;
541         int found;
542
543         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
544         if (ACPI_FAILURE(status)) {
545                 return (status);
546         }
547
548         node = acpi_ns_map_handle_to_node(obj_handle);
549         status = acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
550         if (ACPI_FAILURE(status)) {
551                 return (status);
552         }
553
554         if (!node) {
555                 return (AE_BAD_PARAMETER);
556         }
557
558         /* Run _STA to determine if device is present */
559
560         status = acpi_ut_execute_STA(node, &flags);
561         if (ACPI_FAILURE(status)) {
562                 return (AE_CTRL_DEPTH);
563         }
564
565         if (!(flags & ACPI_STA_DEVICE_PRESENT) &&
566             !(flags & ACPI_STA_DEVICE_FUNCTIONING)) {
567                 /*
568                  * Don't examine the children of the device only when the
569                  * device is neither present nor functional. See ACPI spec,
570                  * description of _STA for more information.
571                  */
572                 return (AE_CTRL_DEPTH);
573         }
574
575         /* Filter based on device HID & CID */
576
577         if (info->hid != NULL) {
578                 status = acpi_ut_execute_HID(node, &hid);
579                 if (status == AE_NOT_FOUND) {
580                         return (AE_OK);
581                 } else if (ACPI_FAILURE(status)) {
582                         return (AE_CTRL_DEPTH);
583                 }
584
585                 if (ACPI_STRNCMP(hid.value, info->hid, sizeof(hid.value)) != 0) {
586
587                         /* Get the list of Compatible IDs */
588
589                         status = acpi_ut_execute_CID(node, &cid);
590                         if (status == AE_NOT_FOUND) {
591                                 return (AE_OK);
592                         } else if (ACPI_FAILURE(status)) {
593                                 return (AE_CTRL_DEPTH);
594                         }
595
596                         /* Walk the CID list */
597
598                         found = 0;
599                         for (i = 0; i < cid->count; i++) {
600                                 if (ACPI_STRNCMP(cid->id[i].value, info->hid,
601                                                  sizeof(struct
602                                                         acpi_compatible_id)) ==
603                                     0) {
604                                         found = 1;
605                                         break;
606                                 }
607                         }
608                         ACPI_FREE(cid);
609                         if (!found)
610                                 return (AE_OK);
611                 }
612         }
613
614         status = info->user_function(obj_handle, nesting_level, info->context,
615                                      return_value);
616         return (status);
617 }
618
619 /*******************************************************************************
620  *
621  * FUNCTION:    acpi_get_devices
622  *
623  * PARAMETERS:  HID                 - HID to search for. Can be NULL.
624  *              user_function       - Called when a matching object is found
625  *              Context             - Passed to user function
626  *              return_value        - Location where return value of
627  *                                    user_function is put if terminated early
628  *
629  * RETURNS      Return value from the user_function if terminated early.
630  *              Otherwise, returns NULL.
631  *
632  * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
633  *              starting (and ending) at the object specified by start_handle.
634  *              The user_function is called whenever an object of type
635  *              Device is found.  If the user function returns
636  *              a non-zero value, the search is terminated immediately and this
637  *              value is returned to the caller.
638  *
639  *              This is a wrapper for walk_namespace, but the callback performs
640  *              additional filtering. Please see acpi_ns_get_device_callback.
641  *
642  ******************************************************************************/
643
644 acpi_status
645 acpi_get_devices(const char *HID,
646                  acpi_walk_callback user_function,
647                  void *context, void **return_value)
648 {
649         acpi_status status;
650         struct acpi_get_devices_info info;
651
652         ACPI_FUNCTION_TRACE(acpi_get_devices);
653
654         /* Parameter validation */
655
656         if (!user_function) {
657                 return_ACPI_STATUS(AE_BAD_PARAMETER);
658         }
659
660         /*
661          * We're going to call their callback from OUR callback, so we need
662          * to know what it is, and their context parameter.
663          */
664         info.hid = HID;
665         info.context = context;
666         info.user_function = user_function;
667
668         /*
669          * Lock the namespace around the walk.
670          * The namespace will be unlocked/locked around each call
671          * to the user function - since this function
672          * must be allowed to make Acpi calls itself.
673          */
674         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
675         if (ACPI_FAILURE(status)) {
676                 return_ACPI_STATUS(status);
677         }
678
679         status = acpi_ns_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
680                                         ACPI_UINT32_MAX, ACPI_NS_WALK_UNLOCK,
681                                         acpi_ns_get_device_callback, &info,
682                                         return_value);
683
684         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
685         return_ACPI_STATUS(status);
686 }
687
688 ACPI_EXPORT_SYMBOL(acpi_get_devices)
689
690 /*******************************************************************************
691  *
692  * FUNCTION:    acpi_attach_data
693  *
694  * PARAMETERS:  obj_handle          - Namespace node
695  *              Handler             - Handler for this attachment
696  *              Data                - Pointer to data to be attached
697  *
698  * RETURN:      Status
699  *
700  * DESCRIPTION: Attach arbitrary data and handler to a namespace node.
701  *
702  ******************************************************************************/
703 acpi_status
704 acpi_attach_data(acpi_handle obj_handle,
705                  acpi_object_handler handler, void *data)
706 {
707         struct acpi_namespace_node *node;
708         acpi_status status;
709
710         /* Parameter validation */
711
712         if (!obj_handle || !handler || !data) {
713                 return (AE_BAD_PARAMETER);
714         }
715
716         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
717         if (ACPI_FAILURE(status)) {
718                 return (status);
719         }
720
721         /* Convert and validate the handle */
722
723         node = acpi_ns_map_handle_to_node(obj_handle);
724         if (!node) {
725                 status = AE_BAD_PARAMETER;
726                 goto unlock_and_exit;
727         }
728
729         status = acpi_ns_attach_data(node, handler, data);
730
731       unlock_and_exit:
732         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
733         return (status);
734 }
735
736 ACPI_EXPORT_SYMBOL(acpi_attach_data)
737
738 /*******************************************************************************
739  *
740  * FUNCTION:    acpi_detach_data
741  *
742  * PARAMETERS:  obj_handle          - Namespace node handle
743  *              Handler             - Handler used in call to acpi_attach_data
744  *
745  * RETURN:      Status
746  *
747  * DESCRIPTION: Remove data that was previously attached to a node.
748  *
749  ******************************************************************************/
750 acpi_status
751 acpi_detach_data(acpi_handle obj_handle, acpi_object_handler handler)
752 {
753         struct acpi_namespace_node *node;
754         acpi_status status;
755
756         /* Parameter validation */
757
758         if (!obj_handle || !handler) {
759                 return (AE_BAD_PARAMETER);
760         }
761
762         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
763         if (ACPI_FAILURE(status)) {
764                 return (status);
765         }
766
767         /* Convert and validate the handle */
768
769         node = acpi_ns_map_handle_to_node(obj_handle);
770         if (!node) {
771                 status = AE_BAD_PARAMETER;
772                 goto unlock_and_exit;
773         }
774
775         status = acpi_ns_detach_data(node, handler);
776
777       unlock_and_exit:
778         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
779         return (status);
780 }
781
782 ACPI_EXPORT_SYMBOL(acpi_detach_data)
783
784 /*******************************************************************************
785  *
786  * FUNCTION:    acpi_get_data
787  *
788  * PARAMETERS:  obj_handle          - Namespace node
789  *              Handler             - Handler used in call to attach_data
790  *              Data                - Where the data is returned
791  *
792  * RETURN:      Status
793  *
794  * DESCRIPTION: Retrieve data that was previously attached to a namespace node.
795  *
796  ******************************************************************************/
797 acpi_status
798 acpi_get_data(acpi_handle obj_handle, acpi_object_handler handler, void **data)
799 {
800         struct acpi_namespace_node *node;
801         acpi_status status;
802
803         /* Parameter validation */
804
805         if (!obj_handle || !handler || !data) {
806                 return (AE_BAD_PARAMETER);
807         }
808
809         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
810         if (ACPI_FAILURE(status)) {
811                 return (status);
812         }
813
814         /* Convert and validate the handle */
815
816         node = acpi_ns_map_handle_to_node(obj_handle);
817         if (!node) {
818                 status = AE_BAD_PARAMETER;
819                 goto unlock_and_exit;
820         }
821
822         status = acpi_ns_get_attached_data(node, handler, data);
823
824       unlock_and_exit:
825         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
826         return (status);
827 }
828
829 ACPI_EXPORT_SYMBOL(acpi_get_data)