1 /*******************************************************************************
3 * Module Name: nsxfeval - Public interfaces to the ACPI subsystem
4 * ACPI Object evaluation interfaces
6 ******************************************************************************/
9 * Copyright (C) 2000 - 2013, Intel Corp.
10 * All rights reserved.
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
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.
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
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42 * POSSIBILITY OF SUCH DAMAGES.
45 #include <linux/export.h>
46 #include <acpi/acpi.h>
51 #define _COMPONENT ACPI_NAMESPACE
52 ACPI_MODULE_NAME("nsxfeval")
54 /* Local prototypes */
55 static void acpi_ns_resolve_references(struct acpi_evaluate_info *info);
57 /*******************************************************************************
59 * FUNCTION: acpi_evaluate_object_typed
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
72 * DESCRIPTION: Find and evaluate the given object, passing the given
73 * parameters if necessary. One of "Handle" or "Pathname" must
76 ******************************************************************************/
79 acpi_evaluate_object_typed(acpi_handle handle,
81 struct acpi_object_list *external_params,
82 struct acpi_buffer *return_buffer,
83 acpi_object_type return_type)
88 ACPI_FUNCTION_TRACE(acpi_evaluate_object_typed);
90 /* Return buffer must be valid */
93 return_ACPI_STATUS(AE_BAD_PARAMETER);
96 if (return_buffer->length == ACPI_ALLOCATE_BUFFER) {
100 /* Evaluate the object */
103 acpi_evaluate_object(handle, pathname, external_params,
105 if (ACPI_FAILURE(status)) {
106 return_ACPI_STATUS(status);
109 /* Type ANY means "don't care" */
111 if (return_type == ACPI_TYPE_ANY) {
112 return_ACPI_STATUS(AE_OK);
115 if (return_buffer->length == 0) {
117 /* Error because caller specifically asked for a return value */
119 ACPI_ERROR((AE_INFO, "No return value"));
120 return_ACPI_STATUS(AE_NULL_OBJECT);
123 /* Examine the object type returned from evaluate_object */
125 if (((union acpi_object *)return_buffer->pointer)->type == return_type) {
126 return_ACPI_STATUS(AE_OK);
129 /* Return object type does not match requested type */
132 "Incorrect return type [%s] requested [%s]",
133 acpi_ut_get_type_name(((union acpi_object *)return_buffer->
135 acpi_ut_get_type_name(return_type)));
139 /* Caller used ACPI_ALLOCATE_BUFFER, free the return buffer */
141 ACPI_FREE(return_buffer->pointer);
142 return_buffer->pointer = NULL;
145 return_buffer->length = 0;
146 return_ACPI_STATUS(AE_TYPE);
149 ACPI_EXPORT_SYMBOL(acpi_evaluate_object_typed)
151 /*******************************************************************************
153 * FUNCTION: acpi_evaluate_object
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.
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)
169 ******************************************************************************/
171 acpi_evaluate_object(acpi_handle handle,
172 acpi_string pathname,
173 struct acpi_object_list *external_params,
174 struct acpi_buffer *return_buffer)
177 struct acpi_evaluate_info *info;
178 acpi_size buffer_space_needed;
181 ACPI_FUNCTION_TRACE(acpi_evaluate_object);
183 /* Allocate and initialize the evaluation information block */
185 info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
187 return_ACPI_STATUS(AE_NO_MEMORY);
190 /* Convert and validate the device handle */
192 info->prefix_node = acpi_ns_validate_handle(handle);
193 if (!info->prefix_node) {
194 status = AE_BAD_PARAMETER;
199 * Get the actual namespace node for the target object.
200 * Handles these cases:
202 * 1) Null node, valid pathname from root (absolute path)
203 * 2) Node and valid pathname (path relative to Node)
204 * 3) Node, Null pathname
206 if ((pathname) && (ACPI_IS_ROOT_PREFIX(pathname[0]))) {
208 /* The path is fully qualified, just evaluate by name */
210 info->prefix_node = NULL;
211 } else if (!handle) {
213 * A handle is optional iff a fully qualified pathname is specified.
214 * Since we've already handled fully qualified names above, this is
218 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
219 "Both Handle and Pathname are NULL"));
221 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
222 "Null Handle with relative pathname [%s]",
226 status = AE_BAD_PARAMETER;
230 info->relative_pathname = pathname;
233 * Convert all external objects passed as arguments to the
234 * internal version(s).
236 if (external_params && external_params->count) {
237 info->param_count = (u16)external_params->count;
239 /* Warn on impossible argument count */
241 if (info->param_count > ACPI_METHOD_NUM_ARGS) {
242 ACPI_WARN_PREDEFINED((AE_INFO, pathname,
244 "Excess arguments (%u) - using only %u",
246 ACPI_METHOD_NUM_ARGS));
248 info->param_count = ACPI_METHOD_NUM_ARGS;
252 * Allocate a new parameter block for the internal objects
253 * Add 1 to count to allow for null terminated internal list
255 info->parameters = ACPI_ALLOCATE_ZEROED(((acpi_size) info->
257 1) * sizeof(void *));
258 if (!info->parameters) {
259 status = AE_NO_MEMORY;
263 /* Convert each external object in the list to an internal object */
265 for (i = 0; i < info->param_count; i++) {
267 acpi_ut_copy_eobject_to_iobject(&external_params->
271 if (ACPI_FAILURE(status)) {
276 info->parameters[info->param_count] = NULL;
282 * Begin incoming argument count analysis. Check for too few args
286 switch (acpi_ns_get_type(info->node)) {
287 case ACPI_TYPE_METHOD:
289 /* Check incoming argument count against the method definition */
291 if (info->obj_desc->method.param_count > info->param_count) {
293 "Insufficient arguments (%u) - %u are required",
295 info->obj_desc->method.param_count));
297 status = AE_MISSING_ARGUMENTS;
301 else if (info->obj_desc->method.param_count < info->param_count) {
302 ACPI_WARNING((AE_INFO,
303 "Excess arguments (%u) - only %u are required",
305 info->obj_desc->method.param_count));
307 /* Just pass the required number of arguments */
309 info->param_count = info->obj_desc->method.param_count;
313 * Any incoming external objects to be passed as arguments to the
314 * method must be converted to internal objects
316 if (info->param_count) {
318 * Allocate a new parameter block for the internal objects
319 * Add 1 to count to allow for null terminated internal list
321 info->parameters = ACPI_ALLOCATE_ZEROED(((acpi_size)
326 if (!info->parameters) {
327 status = AE_NO_MEMORY;
331 /* Convert each external object in the list to an internal object */
333 for (i = 0; i < info->param_count; i++) {
335 acpi_ut_copy_eobject_to_iobject
336 (&external_params->pointer[i],
337 &info->parameters[i]);
338 if (ACPI_FAILURE(status)) {
343 info->parameters[info->param_count] = NULL;
349 /* Warn if arguments passed to an object that is not a method */
351 if (info->param_count) {
352 ACPI_WARNING((AE_INFO,
353 "%u arguments were passed to a non-method ACPI object",
361 /* Now we can evaluate the object */
363 status = acpi_ns_evaluate(info);
366 * If we are expecting a return value, and all went well above,
367 * copy the return value to an external object.
370 if (!info->return_object) {
371 return_buffer->length = 0;
373 if (ACPI_GET_DESCRIPTOR_TYPE(info->return_object) ==
374 ACPI_DESC_TYPE_NAMED) {
376 * If we received a NS Node as a return object, this means that
377 * the object we are evaluating has nothing interesting to
378 * return (such as a mutex, etc.) We return an error because
379 * these types are essentially unsupported by this interface.
380 * We don't check up front because this makes it easier to add
381 * support for various types at a later date if necessary.
384 info->return_object = NULL; /* No need to delete a NS Node */
385 return_buffer->length = 0;
388 if (ACPI_SUCCESS(status)) {
390 /* Dereference Index and ref_of references */
392 acpi_ns_resolve_references(info);
394 /* Get the size of the returned object */
397 acpi_ut_get_object_size(info->return_object,
398 &buffer_space_needed);
399 if (ACPI_SUCCESS(status)) {
401 /* Validate/Allocate/Clear caller buffer */
404 acpi_ut_initialize_buffer
406 buffer_space_needed);
407 if (ACPI_FAILURE(status)) {
409 * Caller's buffer is too small or a new one can't
412 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
413 "Needed buffer size %X, %s\n",
416 acpi_format_exception
419 /* We have enough space for the object, build it */
422 acpi_ut_copy_iobject_to_eobject
423 (info->return_object,
431 if (info->return_object) {
433 * Delete the internal return object. NOTE: Interpreter must be
434 * locked to avoid race condition.
436 acpi_ex_enter_interpreter();
438 /* Remove one reference on the return object (should delete it) */
440 acpi_ut_remove_reference(info->return_object);
441 acpi_ex_exit_interpreter();
446 /* Free the input parameter list (if we created one) */
448 if (info->parameters) {
450 /* Free the allocated parameter block */
452 acpi_ut_delete_internal_object_list(info->parameters);
456 return_ACPI_STATUS(status);
459 ACPI_EXPORT_SYMBOL(acpi_evaluate_object)
461 /*******************************************************************************
463 * FUNCTION: acpi_ns_resolve_references
465 * PARAMETERS: info - Evaluation info block
467 * RETURN: Info->return_object is replaced with the dereferenced object
469 * DESCRIPTION: Dereference certain reference objects. Called before an
470 * internal return object is converted to an external union acpi_object.
472 * Performs an automatic dereference of Index and ref_of reference objects.
473 * These reference objects are not supported by the union acpi_object, so this is a
474 * last resort effort to return something useful. Also, provides compatibility
475 * with other ACPI implementations.
477 * NOTE: does not handle references within returned package objects or nested
478 * references, but this support could be added later if found to be necessary.
480 ******************************************************************************/
481 static void acpi_ns_resolve_references(struct acpi_evaluate_info *info)
483 union acpi_operand_object *obj_desc = NULL;
484 struct acpi_namespace_node *node;
486 /* We are interested in reference objects only */
488 if ((info->return_object)->common.type != ACPI_TYPE_LOCAL_REFERENCE) {
493 * Two types of references are supported - those created by Index and
494 * ref_of operators. A name reference (AML_NAMEPATH_OP) can be converted
495 * to an union acpi_object, so it is not dereferenced here. A ddb_handle
496 * (AML_LOAD_OP) cannot be dereferenced, nor can it be converted to
497 * an union acpi_object.
499 switch (info->return_object->reference.class) {
500 case ACPI_REFCLASS_INDEX:
502 obj_desc = *(info->return_object->reference.where);
505 case ACPI_REFCLASS_REFOF:
507 node = info->return_object->reference.object;
509 obj_desc = node->object;
518 /* Replace the existing reference object */
521 acpi_ut_add_reference(obj_desc);
522 acpi_ut_remove_reference(info->return_object);
523 info->return_object = obj_desc;
529 /*******************************************************************************
531 * FUNCTION: acpi_walk_namespace
533 * PARAMETERS: type - acpi_object_type to search for
534 * start_object - Handle in namespace where search begins
535 * max_depth - Depth to which search is to reach
536 * descending_callback - Called during tree descent
537 * when an object of "Type" is found
538 * ascending_callback - Called during tree ascent
539 * when an object of "Type" is found
540 * context - Passed to user function(s) above
541 * return_value - Location where return value of
542 * user_function is put if terminated early
544 * RETURNS Return value from the user_function if terminated early.
545 * Otherwise, returns NULL.
547 * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
548 * starting (and ending) at the object specified by start_handle.
549 * The callback function is called whenever an object that matches
550 * the type parameter is found. If the callback function returns
551 * a non-zero value, the search is terminated immediately and this
552 * value is returned to the caller.
554 * The point of this procedure is to provide a generic namespace
555 * walk routine that can be called from multiple places to
556 * provide multiple services; the callback function(s) can be
557 * tailored to each task, whether it is a print function,
558 * a compare function, etc.
560 ******************************************************************************/
563 acpi_walk_namespace(acpi_object_type type,
564 acpi_handle start_object,
566 acpi_walk_callback descending_callback,
567 acpi_walk_callback ascending_callback,
568 void *context, void **return_value)
572 ACPI_FUNCTION_TRACE(acpi_walk_namespace);
574 /* Parameter validation */
576 if ((type > ACPI_TYPE_LOCAL_MAX) ||
577 (!max_depth) || (!descending_callback && !ascending_callback)) {
578 return_ACPI_STATUS(AE_BAD_PARAMETER);
582 * Need to acquire the namespace reader lock to prevent interference
583 * with any concurrent table unloads (which causes the deletion of
584 * namespace objects). We cannot allow the deletion of a namespace node
585 * while the user function is using it. The exception to this are the
586 * nodes created and deleted during control method execution -- these
587 * nodes are marked as temporary nodes and are ignored by the namespace
588 * walk. Thus, control methods can be executed while holding the
589 * namespace deletion lock (and the user function can execute control
592 status = acpi_ut_acquire_read_lock(&acpi_gbl_namespace_rw_lock);
593 if (ACPI_FAILURE(status)) {
594 return_ACPI_STATUS(status);
598 * Lock the namespace around the walk. The namespace will be
599 * unlocked/locked around each call to the user function - since the user
600 * function must be allowed to make ACPICA calls itself (for example, it
601 * will typically execute control methods during device enumeration.)
603 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
604 if (ACPI_FAILURE(status)) {
605 goto unlock_and_exit;
608 /* Now we can validate the starting node */
610 if (!acpi_ns_validate_handle(start_object)) {
611 status = AE_BAD_PARAMETER;
612 goto unlock_and_exit2;
615 status = acpi_ns_walk_namespace(type, start_object, max_depth,
617 descending_callback, ascending_callback,
618 context, return_value);
621 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
624 (void)acpi_ut_release_read_lock(&acpi_gbl_namespace_rw_lock);
625 return_ACPI_STATUS(status);
628 ACPI_EXPORT_SYMBOL(acpi_walk_namespace)
630 /*******************************************************************************
632 * FUNCTION: acpi_ns_get_device_callback
634 * PARAMETERS: Callback from acpi_get_device
638 * DESCRIPTION: Takes callbacks from walk_namespace and filters out all non-
639 * present devices, or if they specified a HID, it filters based
642 ******************************************************************************/
644 acpi_ns_get_device_callback(acpi_handle obj_handle,
646 void *context, void **return_value)
648 struct acpi_get_devices_info *info = context;
650 struct acpi_namespace_node *node;
652 struct acpi_pnp_device_id *hid;
653 struct acpi_pnp_device_id_list *cid;
658 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
659 if (ACPI_FAILURE(status)) {
663 node = acpi_ns_validate_handle(obj_handle);
664 status = acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
665 if (ACPI_FAILURE(status)) {
670 return (AE_BAD_PARAMETER);
674 * First, filter based on the device HID and CID.
676 * 01/2010: For this case where a specific HID is requested, we don't
677 * want to run _STA until we have an actual HID match. Thus, we will
678 * not unnecessarily execute _STA on devices for which the caller
679 * doesn't care about. Previously, _STA was executed unconditionally
680 * on all devices found here.
682 * A side-effect of this change is that now we will continue to search
683 * for a matching HID even under device trees where the parent device
684 * would have returned a _STA that indicates it is not present or
685 * not functioning (thus aborting the search on that branch).
687 if (info->hid != NULL) {
688 status = acpi_ut_execute_HID(node, &hid);
689 if (status == AE_NOT_FOUND) {
691 } else if (ACPI_FAILURE(status)) {
692 return (AE_CTRL_DEPTH);
695 no_match = ACPI_STRCMP(hid->string, info->hid);
700 * HID does not match, attempt match within the
701 * list of Compatible IDs (CIDs)
703 status = acpi_ut_execute_CID(node, &cid);
704 if (status == AE_NOT_FOUND) {
706 } else if (ACPI_FAILURE(status)) {
707 return (AE_CTRL_DEPTH);
710 /* Walk the CID list */
713 for (i = 0; i < cid->count; i++) {
714 if (ACPI_STRCMP(cid->ids[i].string, info->hid)
717 /* Found a matching CID */
731 /* Run _STA to determine if device is present */
733 status = acpi_ut_execute_STA(node, &flags);
734 if (ACPI_FAILURE(status)) {
735 return (AE_CTRL_DEPTH);
738 if (!(flags & ACPI_STA_DEVICE_PRESENT) &&
739 !(flags & ACPI_STA_DEVICE_FUNCTIONING)) {
741 * Don't examine the children of the device only when the
742 * device is neither present nor functional. See ACPI spec,
743 * description of _STA for more information.
745 return (AE_CTRL_DEPTH);
748 /* We have a valid device, invoke the user function */
750 status = info->user_function(obj_handle, nesting_level, info->context,
755 /*******************************************************************************
757 * FUNCTION: acpi_get_devices
759 * PARAMETERS: HID - HID to search for. Can be NULL.
760 * user_function - Called when a matching object is found
761 * context - Passed to user function
762 * return_value - Location where return value of
763 * user_function is put if terminated early
765 * RETURNS Return value from the user_function if terminated early.
766 * Otherwise, returns NULL.
768 * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
769 * starting (and ending) at the object specified by start_handle.
770 * The user_function is called whenever an object of type
771 * Device is found. If the user function returns
772 * a non-zero value, the search is terminated immediately and this
773 * value is returned to the caller.
775 * This is a wrapper for walk_namespace, but the callback performs
776 * additional filtering. Please see acpi_ns_get_device_callback.
778 ******************************************************************************/
781 acpi_get_devices(const char *HID,
782 acpi_walk_callback user_function,
783 void *context, void **return_value)
786 struct acpi_get_devices_info info;
788 ACPI_FUNCTION_TRACE(acpi_get_devices);
790 /* Parameter validation */
792 if (!user_function) {
793 return_ACPI_STATUS(AE_BAD_PARAMETER);
797 * We're going to call their callback from OUR callback, so we need
798 * to know what it is, and their context parameter.
801 info.context = context;
802 info.user_function = user_function;
805 * Lock the namespace around the walk.
806 * The namespace will be unlocked/locked around each call
807 * to the user function - since this function
808 * must be allowed to make Acpi calls itself.
810 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
811 if (ACPI_FAILURE(status)) {
812 return_ACPI_STATUS(status);
815 status = acpi_ns_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
816 ACPI_UINT32_MAX, ACPI_NS_WALK_UNLOCK,
817 acpi_ns_get_device_callback, NULL,
818 &info, return_value);
820 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
821 return_ACPI_STATUS(status);
824 ACPI_EXPORT_SYMBOL(acpi_get_devices)
826 /*******************************************************************************
828 * FUNCTION: acpi_attach_data
830 * PARAMETERS: obj_handle - Namespace node
831 * handler - Handler for this attachment
832 * data - Pointer to data to be attached
836 * DESCRIPTION: Attach arbitrary data and handler to a namespace node.
838 ******************************************************************************/
840 acpi_attach_data(acpi_handle obj_handle,
841 acpi_object_handler handler, void *data)
843 struct acpi_namespace_node *node;
846 /* Parameter validation */
848 if (!obj_handle || !handler || !data) {
849 return (AE_BAD_PARAMETER);
852 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
853 if (ACPI_FAILURE(status)) {
857 /* Convert and validate the handle */
859 node = acpi_ns_validate_handle(obj_handle);
861 status = AE_BAD_PARAMETER;
862 goto unlock_and_exit;
865 status = acpi_ns_attach_data(node, handler, data);
868 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
872 ACPI_EXPORT_SYMBOL(acpi_attach_data)
874 /*******************************************************************************
876 * FUNCTION: acpi_detach_data
878 * PARAMETERS: obj_handle - Namespace node handle
879 * handler - Handler used in call to acpi_attach_data
883 * DESCRIPTION: Remove data that was previously attached to a node.
885 ******************************************************************************/
887 acpi_detach_data(acpi_handle obj_handle, acpi_object_handler handler)
889 struct acpi_namespace_node *node;
892 /* Parameter validation */
894 if (!obj_handle || !handler) {
895 return (AE_BAD_PARAMETER);
898 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
899 if (ACPI_FAILURE(status)) {
903 /* Convert and validate the handle */
905 node = acpi_ns_validate_handle(obj_handle);
907 status = AE_BAD_PARAMETER;
908 goto unlock_and_exit;
911 status = acpi_ns_detach_data(node, handler);
914 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
918 ACPI_EXPORT_SYMBOL(acpi_detach_data)
920 /*******************************************************************************
922 * FUNCTION: acpi_get_data
924 * PARAMETERS: obj_handle - Namespace node
925 * handler - Handler used in call to attach_data
926 * data - Where the data is returned
930 * DESCRIPTION: Retrieve data that was previously attached to a namespace node.
932 ******************************************************************************/
934 acpi_get_data(acpi_handle obj_handle, acpi_object_handler handler, void **data)
936 struct acpi_namespace_node *node;
939 /* Parameter validation */
941 if (!obj_handle || !handler || !data) {
942 return (AE_BAD_PARAMETER);
945 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
946 if (ACPI_FAILURE(status)) {
950 /* Convert and validate the handle */
952 node = acpi_ns_validate_handle(obj_handle);
954 status = AE_BAD_PARAMETER;
955 goto unlock_and_exit;
958 status = acpi_ns_get_attached_data(node, handler, data);
961 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
965 ACPI_EXPORT_SYMBOL(acpi_get_data)