ACPICA: Major update for acpi_get_object_info external interface
[linux-2.6/btrfs-unstable.git] / drivers / acpi / acpica / nsxfeval.c
blob4929dbdbc8f0f5082ca157965451a1e413d9f539
1 /*******************************************************************************
3 * Module Name: nsxfeval - Public interfaces to the ACPI subsystem
4 * ACPI Object evaluation interfaces
6 ******************************************************************************/
8 /*
9 * Copyright (C) 2000 - 2008, Intel Corp.
10 * All rights reserved.
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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.
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.
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
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41 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
42 * POSSIBILITY OF SUCH DAMAGES.
45 #include <acpi/acpi.h>
46 #include "accommon.h"
47 #include "acnamesp.h"
48 #include "acinterp.h"
50 #define _COMPONENT ACPI_NAMESPACE
51 ACPI_MODULE_NAME("nsxfeval")
53 /* Local prototypes */
54 static void acpi_ns_resolve_references(struct acpi_evaluate_info *info);
56 /*******************************************************************************
58 * FUNCTION: acpi_evaluate_object_typed
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
69 * RETURN: Status
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)
75 ******************************************************************************/
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)
84 acpi_status status;
85 u8 must_free = FALSE;
87 ACPI_FUNCTION_TRACE(acpi_evaluate_object_typed);
89 /* Return buffer must be valid */
91 if (!return_buffer) {
92 return_ACPI_STATUS(AE_BAD_PARAMETER);
95 if (return_buffer->length == ACPI_ALLOCATE_BUFFER) {
96 must_free = TRUE;
99 /* Evaluate the object */
101 status =
102 acpi_evaluate_object(handle, pathname, external_params,
103 return_buffer);
104 if (ACPI_FAILURE(status)) {
105 return_ACPI_STATUS(status);
108 /* Type ANY means "don't care" */
110 if (return_type == ACPI_TYPE_ANY) {
111 return_ACPI_STATUS(AE_OK);
114 if (return_buffer->length == 0) {
116 /* Error because caller specifically asked for a return value */
118 ACPI_ERROR((AE_INFO, "No return value"));
119 return_ACPI_STATUS(AE_NULL_OBJECT);
122 /* Examine the object type returned from evaluate_object */
124 if (((union acpi_object *)return_buffer->pointer)->type == return_type) {
125 return_ACPI_STATUS(AE_OK);
128 /* Return object type does not match requested type */
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)));
136 if (must_free) {
138 /* Caller used ACPI_ALLOCATE_BUFFER, free the return buffer */
140 ACPI_FREE(return_buffer->pointer);
141 return_buffer->pointer = NULL;
144 return_buffer->length = 0;
145 return_ACPI_STATUS(AE_TYPE);
148 ACPI_EXPORT_SYMBOL(acpi_evaluate_object_typed)
150 /*******************************************************************************
152 * FUNCTION: acpi_evaluate_object
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.
162 * RETURN: Status
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)
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)
175 acpi_status status;
176 struct acpi_evaluate_info *info;
177 acpi_size buffer_space_needed;
178 u32 i;
180 ACPI_FUNCTION_TRACE(acpi_evaluate_object);
182 /* Allocate and initialize the evaluation information block */
184 info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
185 if (!info) {
186 return_ACPI_STATUS(AE_NO_MEMORY);
189 info->pathname = pathname;
191 /* Convert and validate the device handle */
193 info->prefix_node = acpi_ns_map_handle_to_node(handle);
194 if (!info->prefix_node) {
195 status = AE_BAD_PARAMETER;
196 goto cleanup;
200 * If there are parameters to be passed to a control method, the external
201 * objects must all be converted to internal objects
203 if (external_params && external_params->count) {
205 * Allocate a new parameter block for the internal objects
206 * Add 1 to count to allow for null terminated internal list
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;
217 /* Convert each external object in the list to an internal object */
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;
229 info->parameters[external_params->count] = NULL;
233 * Three major cases:
234 * 1) Fully qualified pathname
235 * 2) No handle, not fully qualified pathname (error)
236 * 3) Valid handle
238 if ((pathname) && (acpi_ns_valid_root_prefix(pathname[0]))) {
240 /* The path is fully qualified, just evaluate by name */
242 info->prefix_node = NULL;
243 status = acpi_ns_evaluate(info);
244 } else if (!handle) {
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
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));
259 status = AE_BAD_PARAMETER;
260 } else {
261 /* We have a namespace a node and a possible relative path */
263 status = acpi_ns_evaluate(info);
267 * If we are expecting a return value, and all went well above,
268 * copy the return value to an external object.
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) {
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.
284 status = AE_TYPE;
285 info->return_object = NULL; /* No need to delete a NS Node */
286 return_buffer->length = 0;
289 if (ACPI_SUCCESS(status)) {
291 /* Dereference Index and ref_of references */
293 acpi_ns_resolve_references(info);
295 /* Get the size of the returned object */
297 status =
298 acpi_ut_get_object_size(info->return_object,
299 &buffer_space_needed);
300 if (ACPI_SUCCESS(status)) {
302 /* Validate/Allocate/Clear caller buffer */
304 status =
305 acpi_ut_initialize_buffer
306 (return_buffer,
307 buffer_space_needed);
308 if (ACPI_FAILURE(status)) {
310 * Caller's buffer is too small or a new one can't
311 * be allocated
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 */
322 status =
323 acpi_ut_copy_iobject_to_eobject
324 (info->return_object,
325 return_buffer);
332 if (info->return_object) {
334 * Delete the internal return object. NOTE: Interpreter must be
335 * locked to avoid race condition.
337 acpi_ex_enter_interpreter();
339 /* Remove one reference on the return object (should delete it) */
341 acpi_ut_remove_reference(info->return_object);
342 acpi_ex_exit_interpreter();
345 cleanup:
347 /* Free the input parameter list (if we created one) */
349 if (info->parameters) {
351 /* Free the allocated parameter block */
353 acpi_ut_delete_internal_object_list(info->parameters);
356 ACPI_FREE(info);
357 return_ACPI_STATUS(status);
360 ACPI_EXPORT_SYMBOL(acpi_evaluate_object)
362 /*******************************************************************************
364 * FUNCTION: acpi_ns_resolve_references
366 * PARAMETERS: Info - Evaluation info block
368 * RETURN: Info->return_object is replaced with the dereferenced object
370 * DESCRIPTION: Dereference certain reference objects. Called before an
371 * internal return object is converted to an external union acpi_object.
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.
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.
381 ******************************************************************************/
382 static void acpi_ns_resolve_references(struct acpi_evaluate_info *info)
384 union acpi_operand_object *obj_desc = NULL;
385 struct acpi_namespace_node *node;
387 /* We are interested in reference objects only */
389 if ((info->return_object)->common.type != ACPI_TYPE_LOCAL_REFERENCE) {
390 return;
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.
400 switch (info->return_object->reference.class) {
401 case ACPI_REFCLASS_INDEX:
403 obj_desc = *(info->return_object->reference.where);
404 break;
406 case ACPI_REFCLASS_REFOF:
408 node = info->return_object->reference.object;
409 if (node) {
410 obj_desc = node->object;
412 break;
414 default:
415 return;
418 /* Replace the existing reference object */
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;
426 return;
429 /*******************************************************************************
431 * FUNCTION: acpi_walk_namespace
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
441 * RETURNS Return value from the user_function if terminated early.
442 * Otherwise, returns NULL.
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.
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.
457 ******************************************************************************/
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)
466 acpi_status status;
468 ACPI_FUNCTION_TRACE(acpi_walk_namespace);
470 /* Parameter validation */
472 if ((type > ACPI_TYPE_LOCAL_MAX) || (!max_depth) || (!user_function)) {
473 return_ACPI_STATUS(AE_BAD_PARAMETER);
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.)
487 status = acpi_ut_acquire_read_lock(&acpi_gbl_namespace_rw_lock);
488 if (ACPI_FAILURE(status)) {
489 return status;
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.)
498 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
499 if (ACPI_FAILURE(status)) {
500 goto unlock_and_exit;
503 status = acpi_ns_walk_namespace(type, start_object, max_depth,
504 ACPI_NS_WALK_UNLOCK, user_function,
505 context, return_value);
507 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
509 unlock_and_exit:
510 (void)acpi_ut_release_read_lock(&acpi_gbl_namespace_rw_lock);
511 return_ACPI_STATUS(status);
514 ACPI_EXPORT_SYMBOL(acpi_walk_namespace)
516 /*******************************************************************************
518 * FUNCTION: acpi_ns_get_device_callback
520 * PARAMETERS: Callback from acpi_get_device
522 * RETURN: Status
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.
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)
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 acpica_device_id_list *cid;
540 u32 i;
541 u8 found;
542 int no_match;
544 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
545 if (ACPI_FAILURE(status)) {
546 return (status);
549 node = acpi_ns_map_handle_to_node(obj_handle);
550 status = acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
551 if (ACPI_FAILURE(status)) {
552 return (status);
555 if (!node) {
556 return (AE_BAD_PARAMETER);
559 /* Run _STA to determine if device is present */
561 status = acpi_ut_execute_STA(node, &flags);
562 if (ACPI_FAILURE(status)) {
563 return (AE_CTRL_DEPTH);
566 if (!(flags & ACPI_STA_DEVICE_PRESENT) &&
567 !(flags & ACPI_STA_DEVICE_FUNCTIONING)) {
569 * Don't examine the children of the device only when the
570 * device is neither present nor functional. See ACPI spec,
571 * description of _STA for more information.
573 return (AE_CTRL_DEPTH);
576 /* Filter based on device HID & CID */
578 if (info->hid != NULL) {
579 status = acpi_ut_execute_HID(node, &hid);
580 if (status == AE_NOT_FOUND) {
581 return (AE_OK);
582 } else if (ACPI_FAILURE(status)) {
583 return (AE_CTRL_DEPTH);
586 no_match = ACPI_STRCMP(hid->string, info->hid);
587 ACPI_FREE(hid);
589 if (no_match) {
591 * HID does not match, attempt match within the
592 * list of Compatible IDs (CIDs)
594 status = acpi_ut_execute_CID(node, &cid);
595 if (status == AE_NOT_FOUND) {
596 return (AE_OK);
597 } else if (ACPI_FAILURE(status)) {
598 return (AE_CTRL_DEPTH);
601 /* Walk the CID list */
603 found = 0;
604 for (i = 0; i < cid->count; i++) {
605 if (ACPI_STRCMP(cid->ids[i].string, info->hid)
606 == 0) {
607 found = 1;
608 break;
611 ACPI_FREE(cid);
612 if (!found)
613 return (AE_OK);
617 status = info->user_function(obj_handle, nesting_level, info->context,
618 return_value);
619 return (status);
622 /*******************************************************************************
624 * FUNCTION: acpi_get_devices
626 * PARAMETERS: HID - HID to search for. Can be NULL.
627 * user_function - Called when a matching object is found
628 * Context - Passed to user function
629 * return_value - Location where return value of
630 * user_function is put if terminated early
632 * RETURNS Return value from the user_function if terminated early.
633 * Otherwise, returns NULL.
635 * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
636 * starting (and ending) at the object specified by start_handle.
637 * The user_function is called whenever an object of type
638 * Device is found. If the user function returns
639 * a non-zero value, the search is terminated immediately and this
640 * value is returned to the caller.
642 * This is a wrapper for walk_namespace, but the callback performs
643 * additional filtering. Please see acpi_ns_get_device_callback.
645 ******************************************************************************/
647 acpi_status
648 acpi_get_devices(const char *HID,
649 acpi_walk_callback user_function,
650 void *context, void **return_value)
652 acpi_status status;
653 struct acpi_get_devices_info info;
655 ACPI_FUNCTION_TRACE(acpi_get_devices);
657 /* Parameter validation */
659 if (!user_function) {
660 return_ACPI_STATUS(AE_BAD_PARAMETER);
664 * We're going to call their callback from OUR callback, so we need
665 * to know what it is, and their context parameter.
667 info.hid = HID;
668 info.context = context;
669 info.user_function = user_function;
672 * Lock the namespace around the walk.
673 * The namespace will be unlocked/locked around each call
674 * to the user function - since this function
675 * must be allowed to make Acpi calls itself.
677 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
678 if (ACPI_FAILURE(status)) {
679 return_ACPI_STATUS(status);
682 status = acpi_ns_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
683 ACPI_UINT32_MAX, ACPI_NS_WALK_UNLOCK,
684 acpi_ns_get_device_callback, &info,
685 return_value);
687 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
688 return_ACPI_STATUS(status);
691 ACPI_EXPORT_SYMBOL(acpi_get_devices)
693 /*******************************************************************************
695 * FUNCTION: acpi_attach_data
697 * PARAMETERS: obj_handle - Namespace node
698 * Handler - Handler for this attachment
699 * Data - Pointer to data to be attached
701 * RETURN: Status
703 * DESCRIPTION: Attach arbitrary data and handler to a namespace node.
705 ******************************************************************************/
706 acpi_status
707 acpi_attach_data(acpi_handle obj_handle,
708 acpi_object_handler handler, void *data)
710 struct acpi_namespace_node *node;
711 acpi_status status;
713 /* Parameter validation */
715 if (!obj_handle || !handler || !data) {
716 return (AE_BAD_PARAMETER);
719 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
720 if (ACPI_FAILURE(status)) {
721 return (status);
724 /* Convert and validate the handle */
726 node = acpi_ns_map_handle_to_node(obj_handle);
727 if (!node) {
728 status = AE_BAD_PARAMETER;
729 goto unlock_and_exit;
732 status = acpi_ns_attach_data(node, handler, data);
734 unlock_and_exit:
735 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
736 return (status);
739 ACPI_EXPORT_SYMBOL(acpi_attach_data)
741 /*******************************************************************************
743 * FUNCTION: acpi_detach_data
745 * PARAMETERS: obj_handle - Namespace node handle
746 * Handler - Handler used in call to acpi_attach_data
748 * RETURN: Status
750 * DESCRIPTION: Remove data that was previously attached to a node.
752 ******************************************************************************/
753 acpi_status
754 acpi_detach_data(acpi_handle obj_handle, acpi_object_handler handler)
756 struct acpi_namespace_node *node;
757 acpi_status status;
759 /* Parameter validation */
761 if (!obj_handle || !handler) {
762 return (AE_BAD_PARAMETER);
765 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
766 if (ACPI_FAILURE(status)) {
767 return (status);
770 /* Convert and validate the handle */
772 node = acpi_ns_map_handle_to_node(obj_handle);
773 if (!node) {
774 status = AE_BAD_PARAMETER;
775 goto unlock_and_exit;
778 status = acpi_ns_detach_data(node, handler);
780 unlock_and_exit:
781 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
782 return (status);
785 ACPI_EXPORT_SYMBOL(acpi_detach_data)
787 /*******************************************************************************
789 * FUNCTION: acpi_get_data
791 * PARAMETERS: obj_handle - Namespace node
792 * Handler - Handler used in call to attach_data
793 * Data - Where the data is returned
795 * RETURN: Status
797 * DESCRIPTION: Retrieve data that was previously attached to a namespace node.
799 ******************************************************************************/
800 acpi_status
801 acpi_get_data(acpi_handle obj_handle, acpi_object_handler handler, void **data)
803 struct acpi_namespace_node *node;
804 acpi_status status;
806 /* Parameter validation */
808 if (!obj_handle || !handler || !data) {
809 return (AE_BAD_PARAMETER);
812 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
813 if (ACPI_FAILURE(status)) {
814 return (status);
817 /* Convert and validate the handle */
819 node = acpi_ns_map_handle_to_node(obj_handle);
820 if (!node) {
821 status = AE_BAD_PARAMETER;
822 goto unlock_and_exit;
825 status = acpi_ns_get_attached_data(node, handler, data);
827 unlock_and_exit:
828 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
829 return (status);
832 ACPI_EXPORT_SYMBOL(acpi_get_data)