Revert "ARM: tegra: tegratab: dummy change"
[linux-2.6.git] / 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 - 2012, 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 <linux/export.h>
46 #include <acpi/acpi.h>
47 #include "accommon.h"
48 #include "acnamesp.h"
49 #include "acinterp.h"
50
51 #define _COMPONENT          ACPI_NAMESPACE
52 ACPI_MODULE_NAME("nsxfeval")
53
54 /* Local prototypes */
55 static void acpi_ns_resolve_references(struct acpi_evaluate_info *info);
56
57 /*******************************************************************************
58  *
59  * FUNCTION:    acpi_evaluate_object_typed
60  *
61  * PARAMETERS:  Handle              - Object handle (optional)
62  *              Pathname            - Object pathname (optional)
63  *              external_params     - List of parameters to pass to method,
64  *                                    terminated by NULL.  May be NULL
65  *                                    if no parameters are being passed.
66  *              return_buffer       - Where to put method's return value (if
67  *                                    any).  If NULL, no value is returned.
68  *              return_type         - Expected type of return object
69  *
70  * RETURN:      Status
71  *
72  * DESCRIPTION: Find and evaluate the given object, passing the given
73  *              parameters if necessary.  One of "Handle" or "Pathname" must
74  *              be valid (non-null)
75  *
76  ******************************************************************************/
77
78 acpi_status
79 acpi_evaluate_object_typed(acpi_handle handle,
80                            acpi_string pathname,
81                            struct acpi_object_list *external_params,
82                            struct acpi_buffer *return_buffer,
83                            acpi_object_type return_type)
84 {
85         acpi_status status;
86         u8 must_free = FALSE;
87
88         ACPI_FUNCTION_TRACE(acpi_evaluate_object_typed);
89
90         /* Return buffer must be valid */
91
92         if (!return_buffer) {
93                 return_ACPI_STATUS(AE_BAD_PARAMETER);
94         }
95
96         if (return_buffer->length == ACPI_ALLOCATE_BUFFER) {
97                 must_free = TRUE;
98         }
99
100         /* Evaluate the object */
101
102         status =
103             acpi_evaluate_object(handle, pathname, external_params,
104                                  return_buffer);
105         if (ACPI_FAILURE(status)) {
106                 return_ACPI_STATUS(status);
107         }
108
109         /* Type ANY means "don't care" */
110
111         if (return_type == ACPI_TYPE_ANY) {
112                 return_ACPI_STATUS(AE_OK);
113         }
114
115         if (return_buffer->length == 0) {
116
117                 /* Error because caller specifically asked for a return value */
118
119                 ACPI_ERROR((AE_INFO, "No return value"));
120                 return_ACPI_STATUS(AE_NULL_OBJECT);
121         }
122
123         /* Examine the object type returned from evaluate_object */
124
125         if (((union acpi_object *)return_buffer->pointer)->type == return_type) {
126                 return_ACPI_STATUS(AE_OK);
127         }
128
129         /* Return object type does not match requested type */
130
131         ACPI_ERROR((AE_INFO,
132                     "Incorrect return type [%s] requested [%s]",
133                     acpi_ut_get_type_name(((union acpi_object *)return_buffer->
134                                            pointer)->type),
135                     acpi_ut_get_type_name(return_type)));
136
137         if (must_free) {
138
139                 /* Caller used ACPI_ALLOCATE_BUFFER, free the return buffer */
140
141                 ACPI_FREE(return_buffer->pointer);
142                 return_buffer->pointer = NULL;
143         }
144
145         return_buffer->length = 0;
146         return_ACPI_STATUS(AE_TYPE);
147 }
148
149 ACPI_EXPORT_SYMBOL(acpi_evaluate_object_typed)
150
151 /*******************************************************************************
152  *
153  * FUNCTION:    acpi_evaluate_object
154  *
155  * PARAMETERS:  Handle              - Object handle (optional)
156  *              Pathname            - Object pathname (optional)
157  *              external_params     - List of parameters to pass to method,
158  *                                    terminated by NULL.  May be NULL
159  *                                    if no parameters are being passed.
160  *              return_buffer       - Where to put method's return value (if
161  *                                    any).  If NULL, no value is returned.
162  *
163  * RETURN:      Status
164  *
165  * DESCRIPTION: Find and evaluate the given object, passing the given
166  *              parameters if necessary.  One of "Handle" or "Pathname" must
167  *              be valid (non-null)
168  *
169  ******************************************************************************/
170 acpi_status
171 acpi_evaluate_object(acpi_handle handle,
172                      acpi_string pathname,
173                      struct acpi_object_list *external_params,
174                      struct acpi_buffer *return_buffer)
175 {
176         acpi_status status;
177         struct acpi_evaluate_info *info;
178         acpi_size buffer_space_needed;
179         u32 i;
180
181         ACPI_FUNCTION_TRACE(acpi_evaluate_object);
182
183         /* Allocate and initialize the evaluation information block */
184
185         info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
186         if (!info) {
187                 return_ACPI_STATUS(AE_NO_MEMORY);
188         }
189
190         info->pathname = pathname;
191
192         /* Convert and validate the device handle */
193
194         info->prefix_node = acpi_ns_validate_handle(handle);
195         if (!info->prefix_node) {
196                 status = AE_BAD_PARAMETER;
197                 goto cleanup;
198         }
199
200         /*
201          * If there are parameters to be passed to a control method, the external
202          * objects must all be converted to internal objects
203          */
204         if (external_params && external_params->count) {
205                 /*
206                  * Allocate a new parameter block for the internal objects
207                  * Add 1 to count to allow for null terminated internal list
208                  */
209                 info->parameters = ACPI_ALLOCATE_ZEROED(((acpi_size)
210                                                          external_params->
211                                                          count +
212                                                          1) * sizeof(void *));
213                 if (!info->parameters) {
214                         status = AE_NO_MEMORY;
215                         goto cleanup;
216                 }
217
218                 /* Convert each external object in the list to an internal object */
219
220                 for (i = 0; i < external_params->count; i++) {
221                         status =
222                             acpi_ut_copy_eobject_to_iobject(&external_params->
223                                                             pointer[i],
224                                                             &info->
225                                                             parameters[i]);
226                         if (ACPI_FAILURE(status)) {
227                                 goto cleanup;
228                         }
229                 }
230                 info->parameters[external_params->count] = NULL;
231         }
232
233         /*
234          * Three major cases:
235          * 1) Fully qualified pathname
236          * 2) No handle, not fully qualified pathname (error)
237          * 3) Valid handle
238          */
239         if ((pathname) && (acpi_ns_valid_root_prefix(pathname[0]))) {
240
241                 /* The path is fully qualified, just evaluate by name */
242
243                 info->prefix_node = NULL;
244                 status = acpi_ns_evaluate(info);
245         } else if (!handle) {
246                 /*
247                  * A handle is optional iff a fully qualified pathname is specified.
248                  * Since we've already handled fully qualified names above, this is
249                  * an error
250                  */
251                 if (!pathname) {
252                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
253                                           "Both Handle and Pathname are NULL"));
254                 } else {
255                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
256                                           "Null Handle with relative pathname [%s]",
257                                           pathname));
258                 }
259
260                 status = AE_BAD_PARAMETER;
261         } else {
262                 /* We have a namespace a node and a possible relative path */
263
264                 status = acpi_ns_evaluate(info);
265         }
266
267         /*
268          * If we are expecting a return value, and all went well above,
269          * copy the return value to an external object.
270          */
271         if (return_buffer) {
272                 if (!info->return_object) {
273                         return_buffer->length = 0;
274                 } else {
275                         if (ACPI_GET_DESCRIPTOR_TYPE(info->return_object) ==
276                             ACPI_DESC_TYPE_NAMED) {
277                                 /*
278                                  * If we received a NS Node as a return object, this means that
279                                  * the object we are evaluating has nothing interesting to
280                                  * return (such as a mutex, etc.)  We return an error because
281                                  * these types are essentially unsupported by this interface.
282                                  * We don't check up front because this makes it easier to add
283                                  * support for various types at a later date if necessary.
284                                  */
285                                 status = AE_TYPE;
286                                 info->return_object = NULL;     /* No need to delete a NS Node */
287                                 return_buffer->length = 0;
288                         }
289
290                         if (ACPI_SUCCESS(status)) {
291
292                                 /* Dereference Index and ref_of references */
293
294                                 acpi_ns_resolve_references(info);
295
296                                 /* Get the size of the returned object */
297
298                                 status =
299                                     acpi_ut_get_object_size(info->return_object,
300                                                             &buffer_space_needed);
301                                 if (ACPI_SUCCESS(status)) {
302
303                                         /* Validate/Allocate/Clear caller buffer */
304
305                                         status =
306                                             acpi_ut_initialize_buffer
307                                             (return_buffer,
308                                              buffer_space_needed);
309                                         if (ACPI_FAILURE(status)) {
310                                                 /*
311                                                  * Caller's buffer is too small or a new one can't
312                                                  * be allocated
313                                                  */
314                                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
315                                                                   "Needed buffer size %X, %s\n",
316                                                                   (u32)
317                                                                   buffer_space_needed,
318                                                                   acpi_format_exception
319                                                                   (status)));
320                                         } else {
321                                                 /* We have enough space for the object, build it */
322
323                                                 status =
324                                                     acpi_ut_copy_iobject_to_eobject
325                                                     (info->return_object,
326                                                      return_buffer);
327                                         }
328                                 }
329                         }
330                 }
331         }
332
333         if (info->return_object) {
334                 /*
335                  * Delete the internal return object. NOTE: Interpreter must be
336                  * locked to avoid race condition.
337                  */
338                 acpi_ex_enter_interpreter();
339
340                 /* Remove one reference on the return object (should delete it) */
341
342                 acpi_ut_remove_reference(info->return_object);
343                 acpi_ex_exit_interpreter();
344         }
345
346       cleanup:
347
348         /* Free the input parameter list (if we created one) */
349
350         if (info->parameters) {
351
352                 /* Free the allocated parameter block */
353
354                 acpi_ut_delete_internal_object_list(info->parameters);
355         }
356
357         ACPI_FREE(info);
358         return_ACPI_STATUS(status);
359 }
360
361 ACPI_EXPORT_SYMBOL(acpi_evaluate_object)
362
363 /*******************************************************************************
364  *
365  * FUNCTION:    acpi_ns_resolve_references
366  *
367  * PARAMETERS:  Info                    - Evaluation info block
368  *
369  * RETURN:      Info->return_object is replaced with the dereferenced object
370  *
371  * DESCRIPTION: Dereference certain reference objects. Called before an
372  *              internal return object is converted to an external union acpi_object.
373  *
374  * Performs an automatic dereference of Index and ref_of reference objects.
375  * These reference objects are not supported by the union acpi_object, so this is a
376  * last resort effort to return something useful. Also, provides compatibility
377  * with other ACPI implementations.
378  *
379  * NOTE: does not handle references within returned package objects or nested
380  * references, but this support could be added later if found to be necessary.
381  *
382  ******************************************************************************/
383 static void acpi_ns_resolve_references(struct acpi_evaluate_info *info)
384 {
385         union acpi_operand_object *obj_desc = NULL;
386         struct acpi_namespace_node *node;
387
388         /* We are interested in reference objects only */
389
390         if ((info->return_object)->common.type != ACPI_TYPE_LOCAL_REFERENCE) {
391                 return;
392         }
393
394         /*
395          * Two types of references are supported - those created by Index and
396          * ref_of operators. A name reference (AML_NAMEPATH_OP) can be converted
397          * to an union acpi_object, so it is not dereferenced here. A ddb_handle
398          * (AML_LOAD_OP) cannot be dereferenced, nor can it be converted to
399          * an union acpi_object.
400          */
401         switch (info->return_object->reference.class) {
402         case ACPI_REFCLASS_INDEX:
403
404                 obj_desc = *(info->return_object->reference.where);
405                 break;
406
407         case ACPI_REFCLASS_REFOF:
408
409                 node = info->return_object->reference.object;
410                 if (node) {
411                         obj_desc = node->object;
412                 }
413                 break;
414
415         default:
416                 return;
417         }
418
419         /* Replace the existing reference object */
420
421         if (obj_desc) {
422                 acpi_ut_add_reference(obj_desc);
423                 acpi_ut_remove_reference(info->return_object);
424                 info->return_object = obj_desc;
425         }
426
427         return;
428 }
429
430 /*******************************************************************************
431  *
432  * FUNCTION:    acpi_walk_namespace
433  *
434  * PARAMETERS:  Type                - acpi_object_type to search for
435  *              start_object        - Handle in namespace where search begins
436  *              max_depth           - Depth to which search is to reach
437  *              pre_order_visit     - Called during tree pre-order visit
438  *                                    when an object of "Type" is found
439  *              post_order_visit    - Called during tree post-order visit
440  *                                    when an object of "Type" is found
441  *              Context             - Passed to user function(s) above
442  *              return_value        - Location where return value of
443  *                                    user_function is put if terminated early
444  *
445  * RETURNS      Return value from the user_function if terminated early.
446  *              Otherwise, returns NULL.
447  *
448  * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
449  *              starting (and ending) at the object specified by start_handle.
450  *              The callback function is called whenever an object that matches
451  *              the type parameter is found. If the callback function returns
452  *              a non-zero value, the search is terminated immediately and this
453  *              value is returned to the caller.
454  *
455  *              The point of this procedure is to provide a generic namespace
456  *              walk routine that can be called from multiple places to
457  *              provide multiple services; the callback function(s) can be
458  *              tailored to each task, whether it is a print function,
459  *              a compare function, etc.
460  *
461  ******************************************************************************/
462
463 acpi_status
464 acpi_walk_namespace(acpi_object_type type,
465                     acpi_handle start_object,
466                     u32 max_depth,
467                     acpi_walk_callback pre_order_visit,
468                     acpi_walk_callback post_order_visit,
469                     void *context, void **return_value)
470 {
471         acpi_status status;
472
473         ACPI_FUNCTION_TRACE(acpi_walk_namespace);
474
475         /* Parameter validation */
476
477         if ((type > ACPI_TYPE_LOCAL_MAX) ||
478             (!max_depth) || (!pre_order_visit && !post_order_visit)) {
479                 return_ACPI_STATUS(AE_BAD_PARAMETER);
480         }
481
482         /*
483          * Need to acquire the namespace reader lock to prevent interference
484          * with any concurrent table unloads (which causes the deletion of
485          * namespace objects). We cannot allow the deletion of a namespace node
486          * while the user function is using it. The exception to this are the
487          * nodes created and deleted during control method execution -- these
488          * nodes are marked as temporary nodes and are ignored by the namespace
489          * walk. Thus, control methods can be executed while holding the
490          * namespace deletion lock (and the user function can execute control
491          * methods.)
492          */
493         status = acpi_ut_acquire_read_lock(&acpi_gbl_namespace_rw_lock);
494         if (ACPI_FAILURE(status)) {
495                 return status;
496         }
497
498         /*
499          * Lock the namespace around the walk. The namespace will be
500          * unlocked/locked around each call to the user function - since the user
501          * function must be allowed to make ACPICA calls itself (for example, it
502          * will typically execute control methods during device enumeration.)
503          */
504         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
505         if (ACPI_FAILURE(status)) {
506                 goto unlock_and_exit;
507         }
508
509         status = acpi_ns_walk_namespace(type, start_object, max_depth,
510                                         ACPI_NS_WALK_UNLOCK, pre_order_visit,
511                                         post_order_visit, context,
512                                         return_value);
513
514         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
515
516       unlock_and_exit:
517         (void)acpi_ut_release_read_lock(&acpi_gbl_namespace_rw_lock);
518         return_ACPI_STATUS(status);
519 }
520
521 ACPI_EXPORT_SYMBOL(acpi_walk_namespace)
522
523 /*******************************************************************************
524  *
525  * FUNCTION:    acpi_ns_get_device_callback
526  *
527  * PARAMETERS:  Callback from acpi_get_device
528  *
529  * RETURN:      Status
530  *
531  * DESCRIPTION: Takes callbacks from walk_namespace and filters out all non-
532  *              present devices, or if they specified a HID, it filters based
533  *              on that.
534  *
535  ******************************************************************************/
536 static acpi_status
537 acpi_ns_get_device_callback(acpi_handle obj_handle,
538                             u32 nesting_level,
539                             void *context, void **return_value)
540 {
541         struct acpi_get_devices_info *info = context;
542         acpi_status status;
543         struct acpi_namespace_node *node;
544         u32 flags;
545         struct acpica_device_id *hid;
546         struct acpica_device_id_list *cid;
547         u32 i;
548         u8 found;
549         int no_match;
550
551         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
552         if (ACPI_FAILURE(status)) {
553                 return (status);
554         }
555
556         node = acpi_ns_validate_handle(obj_handle);
557         status = acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
558         if (ACPI_FAILURE(status)) {
559                 return (status);
560         }
561
562         if (!node) {
563                 return (AE_BAD_PARAMETER);
564         }
565
566         /*
567          * First, filter based on the device HID and CID.
568          *
569          * 01/2010: For this case where a specific HID is requested, we don't
570          * want to run _STA until we have an actual HID match. Thus, we will
571          * not unnecessarily execute _STA on devices for which the caller
572          * doesn't care about. Previously, _STA was executed unconditionally
573          * on all devices found here.
574          *
575          * A side-effect of this change is that now we will continue to search
576          * for a matching HID even under device trees where the parent device
577          * would have returned a _STA that indicates it is not present or
578          * not functioning (thus aborting the search on that branch).
579          */
580         if (info->hid != NULL) {
581                 status = acpi_ut_execute_HID(node, &hid);
582                 if (status == AE_NOT_FOUND) {
583                         return (AE_OK);
584                 } else if (ACPI_FAILURE(status)) {
585                         return (AE_CTRL_DEPTH);
586                 }
587
588                 no_match = ACPI_STRCMP(hid->string, info->hid);
589                 ACPI_FREE(hid);
590
591                 if (no_match) {
592                         /*
593                          * HID does not match, attempt match within the
594                          * list of Compatible IDs (CIDs)
595                          */
596                         status = acpi_ut_execute_CID(node, &cid);
597                         if (status == AE_NOT_FOUND) {
598                                 return (AE_OK);
599                         } else if (ACPI_FAILURE(status)) {
600                                 return (AE_CTRL_DEPTH);
601                         }
602
603                         /* Walk the CID list */
604
605                         found = 0;
606                         for (i = 0; i < cid->count; i++) {
607                                 if (ACPI_STRCMP(cid->ids[i].string, info->hid)
608                                     == 0) {
609                                         found = 1;
610                                         break;
611                                 }
612                         }
613                         ACPI_FREE(cid);
614                         if (!found)
615                                 return (AE_OK);
616                 }
617         }
618
619         /* Run _STA to determine if device is present */
620
621         status = acpi_ut_execute_STA(node, &flags);
622         if (ACPI_FAILURE(status)) {
623                 return (AE_CTRL_DEPTH);
624         }
625
626         if (!(flags & ACPI_STA_DEVICE_PRESENT) &&
627             !(flags & ACPI_STA_DEVICE_FUNCTIONING)) {
628                 /*
629                  * Don't examine the children of the device only when the
630                  * device is neither present nor functional. See ACPI spec,
631                  * description of _STA for more information.
632                  */
633                 return (AE_CTRL_DEPTH);
634         }
635
636         /* We have a valid device, invoke the user function */
637
638         status = info->user_function(obj_handle, nesting_level, info->context,
639                                      return_value);
640         return (status);
641 }
642
643 /*******************************************************************************
644  *
645  * FUNCTION:    acpi_get_devices
646  *
647  * PARAMETERS:  HID                 - HID to search for. Can be NULL.
648  *              user_function       - Called when a matching object is found
649  *              Context             - Passed to user function
650  *              return_value        - Location where return value of
651  *                                    user_function is put if terminated early
652  *
653  * RETURNS      Return value from the user_function if terminated early.
654  *              Otherwise, returns NULL.
655  *
656  * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
657  *              starting (and ending) at the object specified by start_handle.
658  *              The user_function is called whenever an object of type
659  *              Device is found.  If the user function returns
660  *              a non-zero value, the search is terminated immediately and this
661  *              value is returned to the caller.
662  *
663  *              This is a wrapper for walk_namespace, but the callback performs
664  *              additional filtering. Please see acpi_ns_get_device_callback.
665  *
666  ******************************************************************************/
667
668 acpi_status
669 acpi_get_devices(const char *HID,
670                  acpi_walk_callback user_function,
671                  void *context, void **return_value)
672 {
673         acpi_status status;
674         struct acpi_get_devices_info info;
675
676         ACPI_FUNCTION_TRACE(acpi_get_devices);
677
678         /* Parameter validation */
679
680         if (!user_function) {
681                 return_ACPI_STATUS(AE_BAD_PARAMETER);
682         }
683
684         /*
685          * We're going to call their callback from OUR callback, so we need
686          * to know what it is, and their context parameter.
687          */
688         info.hid = HID;
689         info.context = context;
690         info.user_function = user_function;
691
692         /*
693          * Lock the namespace around the walk.
694          * The namespace will be unlocked/locked around each call
695          * to the user function - since this function
696          * must be allowed to make Acpi calls itself.
697          */
698         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
699         if (ACPI_FAILURE(status)) {
700                 return_ACPI_STATUS(status);
701         }
702
703         status = acpi_ns_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
704                                         ACPI_UINT32_MAX, ACPI_NS_WALK_UNLOCK,
705                                         acpi_ns_get_device_callback, NULL,
706                                         &info, return_value);
707
708         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
709         return_ACPI_STATUS(status);
710 }
711
712 ACPI_EXPORT_SYMBOL(acpi_get_devices)
713
714 /*******************************************************************************
715  *
716  * FUNCTION:    acpi_attach_data
717  *
718  * PARAMETERS:  obj_handle          - Namespace node
719  *              Handler             - Handler for this attachment
720  *              Data                - Pointer to data to be attached
721  *
722  * RETURN:      Status
723  *
724  * DESCRIPTION: Attach arbitrary data and handler to a namespace node.
725  *
726  ******************************************************************************/
727 acpi_status
728 acpi_attach_data(acpi_handle obj_handle,
729                  acpi_object_handler handler, void *data)
730 {
731         struct acpi_namespace_node *node;
732         acpi_status status;
733
734         /* Parameter validation */
735
736         if (!obj_handle || !handler || !data) {
737                 return (AE_BAD_PARAMETER);
738         }
739
740         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
741         if (ACPI_FAILURE(status)) {
742                 return (status);
743         }
744
745         /* Convert and validate the handle */
746
747         node = acpi_ns_validate_handle(obj_handle);
748         if (!node) {
749                 status = AE_BAD_PARAMETER;
750                 goto unlock_and_exit;
751         }
752
753         status = acpi_ns_attach_data(node, handler, data);
754
755       unlock_and_exit:
756         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
757         return (status);
758 }
759
760 ACPI_EXPORT_SYMBOL(acpi_attach_data)
761
762 /*******************************************************************************
763  *
764  * FUNCTION:    acpi_detach_data
765  *
766  * PARAMETERS:  obj_handle          - Namespace node handle
767  *              Handler             - Handler used in call to acpi_attach_data
768  *
769  * RETURN:      Status
770  *
771  * DESCRIPTION: Remove data that was previously attached to a node.
772  *
773  ******************************************************************************/
774 acpi_status
775 acpi_detach_data(acpi_handle obj_handle, acpi_object_handler handler)
776 {
777         struct acpi_namespace_node *node;
778         acpi_status status;
779
780         /* Parameter validation */
781
782         if (!obj_handle || !handler) {
783                 return (AE_BAD_PARAMETER);
784         }
785
786         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
787         if (ACPI_FAILURE(status)) {
788                 return (status);
789         }
790
791         /* Convert and validate the handle */
792
793         node = acpi_ns_validate_handle(obj_handle);
794         if (!node) {
795                 status = AE_BAD_PARAMETER;
796                 goto unlock_and_exit;
797         }
798
799         status = acpi_ns_detach_data(node, handler);
800
801       unlock_and_exit:
802         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
803         return (status);
804 }
805
806 ACPI_EXPORT_SYMBOL(acpi_detach_data)
807
808 /*******************************************************************************
809  *
810  * FUNCTION:    acpi_get_data
811  *
812  * PARAMETERS:  obj_handle          - Namespace node
813  *              Handler             - Handler used in call to attach_data
814  *              Data                - Where the data is returned
815  *
816  * RETURN:      Status
817  *
818  * DESCRIPTION: Retrieve data that was previously attached to a namespace node.
819  *
820  ******************************************************************************/
821 acpi_status
822 acpi_get_data(acpi_handle obj_handle, acpi_object_handler handler, void **data)
823 {
824         struct acpi_namespace_node *node;
825         acpi_status status;
826
827         /* Parameter validation */
828
829         if (!obj_handle || !handler || !data) {
830                 return (AE_BAD_PARAMETER);
831         }
832
833         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
834         if (ACPI_FAILURE(status)) {
835                 return (status);
836         }
837
838         /* Convert and validate the handle */
839
840         node = acpi_ns_validate_handle(obj_handle);
841         if (!node) {
842                 status = AE_BAD_PARAMETER;
843                 goto unlock_and_exit;
844         }
845
846         status = acpi_ns_get_attached_data(node, handler, data);
847
848       unlock_and_exit:
849         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
850         return (status);
851 }
852
853 ACPI_EXPORT_SYMBOL(acpi_get_data)