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
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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.
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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 info->pathname = pathname;
192 /* Convert and validate the device handle */
194 info->prefix_node = acpi_ns_validate_handle(handle);
195 if (!info->prefix_node) {
196 status = AE_BAD_PARAMETER;
201 * If there are parameters to be passed to a control method, the external
202 * objects must all be converted to internal objects
204 if (external_params && external_params->count) {
206 * Allocate a new parameter block for the internal objects
207 * Add 1 to count to allow for null terminated internal list
209 info->parameters = ACPI_ALLOCATE_ZEROED(((acpi_size)
212 1) * sizeof(void *));
213 if (!info->parameters) {
214 status = AE_NO_MEMORY;
218 /* Convert each external object in the list to an internal object */
220 for (i = 0; i < external_params->count; i++) {
222 acpi_ut_copy_eobject_to_iobject(&external_params->
226 if (ACPI_FAILURE(status)) {
230 info->parameters[external_params->count] = NULL;
235 * 1) Fully qualified pathname
236 * 2) No handle, not fully qualified pathname (error)
239 if ((pathname) && (ACPI_IS_ROOT_PREFIX(pathname[0]))) {
241 /* The path is fully qualified, just evaluate by name */
243 info->prefix_node = NULL;
244 status = acpi_ns_evaluate(info);
245 } else if (!handle) {
247 * A handle is optional iff a fully qualified pathname is specified.
248 * Since we've already handled fully qualified names above, this is
252 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
253 "Both Handle and Pathname are NULL"));
255 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
256 "Null Handle with relative pathname [%s]",
260 status = AE_BAD_PARAMETER;
262 /* We have a namespace a node and a possible relative path */
264 status = acpi_ns_evaluate(info);
268 * If we are expecting a return value, and all went well above,
269 * copy the return value to an external object.
272 if (!info->return_object) {
273 return_buffer->length = 0;
275 if (ACPI_GET_DESCRIPTOR_TYPE(info->return_object) ==
276 ACPI_DESC_TYPE_NAMED) {
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.
286 info->return_object = NULL; /* No need to delete a NS Node */
287 return_buffer->length = 0;
290 if (ACPI_SUCCESS(status)) {
292 /* Dereference Index and ref_of references */
294 acpi_ns_resolve_references(info);
296 /* Get the size of the returned object */
299 acpi_ut_get_object_size(info->return_object,
300 &buffer_space_needed);
301 if (ACPI_SUCCESS(status)) {
303 /* Validate/Allocate/Clear caller buffer */
306 acpi_ut_initialize_buffer
308 buffer_space_needed);
309 if (ACPI_FAILURE(status)) {
311 * Caller's buffer is too small or a new one can't
314 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
315 "Needed buffer size %X, %s\n",
318 acpi_format_exception
321 /* We have enough space for the object, build it */
324 acpi_ut_copy_iobject_to_eobject
325 (info->return_object,
333 if (info->return_object) {
335 * Delete the internal return object. NOTE: Interpreter must be
336 * locked to avoid race condition.
338 acpi_ex_enter_interpreter();
340 /* Remove one reference on the return object (should delete it) */
342 acpi_ut_remove_reference(info->return_object);
343 acpi_ex_exit_interpreter();
348 /* Free the input parameter list (if we created one) */
350 if (info->parameters) {
352 /* Free the allocated parameter block */
354 acpi_ut_delete_internal_object_list(info->parameters);
358 return_ACPI_STATUS(status);
361 ACPI_EXPORT_SYMBOL(acpi_evaluate_object)
363 /*******************************************************************************
365 * FUNCTION: acpi_ns_resolve_references
367 * PARAMETERS: info - Evaluation info block
369 * RETURN: Info->return_object is replaced with the dereferenced object
371 * DESCRIPTION: Dereference certain reference objects. Called before an
372 * internal return object is converted to an external union acpi_object.
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.
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.
382 ******************************************************************************/
383 static void acpi_ns_resolve_references(struct acpi_evaluate_info *info)
385 union acpi_operand_object *obj_desc = NULL;
386 struct acpi_namespace_node *node;
388 /* We are interested in reference objects only */
390 if ((info->return_object)->common.type != ACPI_TYPE_LOCAL_REFERENCE) {
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.
401 switch (info->return_object->reference.class) {
402 case ACPI_REFCLASS_INDEX:
404 obj_desc = *(info->return_object->reference.where);
407 case ACPI_REFCLASS_REFOF:
409 node = info->return_object->reference.object;
411 obj_desc = node->object;
419 /* Replace the existing reference object */
422 acpi_ut_add_reference(obj_desc);
423 acpi_ut_remove_reference(info->return_object);
424 info->return_object = obj_desc;
430 /*******************************************************************************
432 * FUNCTION: acpi_walk_namespace
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
445 * RETURNS Return value from the user_function if terminated early.
446 * Otherwise, returns NULL.
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.
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.
461 ******************************************************************************/
464 acpi_walk_namespace(acpi_object_type type,
465 acpi_handle start_object,
467 acpi_walk_callback pre_order_visit,
468 acpi_walk_callback post_order_visit,
469 void *context, void **return_value)
473 ACPI_FUNCTION_TRACE(acpi_walk_namespace);
475 /* Parameter validation */
477 if ((type > ACPI_TYPE_LOCAL_MAX) ||
478 (!max_depth) || (!pre_order_visit && !post_order_visit)) {
479 return_ACPI_STATUS(AE_BAD_PARAMETER);
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
493 status = acpi_ut_acquire_read_lock(&acpi_gbl_namespace_rw_lock);
494 if (ACPI_FAILURE(status)) {
495 return_ACPI_STATUS(status);
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.)
504 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
505 if (ACPI_FAILURE(status)) {
506 goto unlock_and_exit;
509 status = acpi_ns_walk_namespace(type, start_object, max_depth,
510 ACPI_NS_WALK_UNLOCK, pre_order_visit,
511 post_order_visit, context,
514 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
517 (void)acpi_ut_release_read_lock(&acpi_gbl_namespace_rw_lock);
518 return_ACPI_STATUS(status);
521 ACPI_EXPORT_SYMBOL(acpi_walk_namespace)
523 /*******************************************************************************
525 * FUNCTION: acpi_ns_get_device_callback
527 * PARAMETERS: Callback from acpi_get_device
531 * DESCRIPTION: Takes callbacks from walk_namespace and filters out all non-
532 * present devices, or if they specified a HID, it filters based
535 ******************************************************************************/
537 acpi_ns_get_device_callback(acpi_handle obj_handle,
539 void *context, void **return_value)
541 struct acpi_get_devices_info *info = context;
543 struct acpi_namespace_node *node;
545 struct acpi_pnp_device_id *hid;
546 struct acpi_pnp_device_id_list *cid;
551 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
552 if (ACPI_FAILURE(status)) {
556 node = acpi_ns_validate_handle(obj_handle);
557 status = acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
558 if (ACPI_FAILURE(status)) {
563 return (AE_BAD_PARAMETER);
567 * First, filter based on the device HID and CID.
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.
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).
580 if (info->hid != NULL) {
581 status = acpi_ut_execute_HID(node, &hid);
582 if (status == AE_NOT_FOUND) {
584 } else if (ACPI_FAILURE(status)) {
585 return (AE_CTRL_DEPTH);
588 no_match = ACPI_STRCMP(hid->string, info->hid);
593 * HID does not match, attempt match within the
594 * list of Compatible IDs (CIDs)
596 status = acpi_ut_execute_CID(node, &cid);
597 if (status == AE_NOT_FOUND) {
599 } else if (ACPI_FAILURE(status)) {
600 return (AE_CTRL_DEPTH);
603 /* Walk the CID list */
606 for (i = 0; i < cid->count; i++) {
607 if (ACPI_STRCMP(cid->ids[i].string, info->hid)
610 /* Found a matching CID */
624 /* Run _STA to determine if device is present */
626 status = acpi_ut_execute_STA(node, &flags);
627 if (ACPI_FAILURE(status)) {
628 return (AE_CTRL_DEPTH);
631 if (!(flags & ACPI_STA_DEVICE_PRESENT) &&
632 !(flags & ACPI_STA_DEVICE_FUNCTIONING)) {
634 * Don't examine the children of the device only when the
635 * device is neither present nor functional. See ACPI spec,
636 * description of _STA for more information.
638 return (AE_CTRL_DEPTH);
641 /* We have a valid device, invoke the user function */
643 status = info->user_function(obj_handle, nesting_level, info->context,
648 /*******************************************************************************
650 * FUNCTION: acpi_get_devices
652 * PARAMETERS: HID - HID to search for. Can be NULL.
653 * user_function - Called when a matching object is found
654 * context - Passed to user function
655 * return_value - Location where return value of
656 * user_function is put if terminated early
658 * RETURNS Return value from the user_function if terminated early.
659 * Otherwise, returns NULL.
661 * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
662 * starting (and ending) at the object specified by start_handle.
663 * The user_function is called whenever an object of type
664 * Device is found. If the user function returns
665 * a non-zero value, the search is terminated immediately and this
666 * value is returned to the caller.
668 * This is a wrapper for walk_namespace, but the callback performs
669 * additional filtering. Please see acpi_ns_get_device_callback.
671 ******************************************************************************/
674 acpi_get_devices(const char *HID,
675 acpi_walk_callback user_function,
676 void *context, void **return_value)
679 struct acpi_get_devices_info info;
681 ACPI_FUNCTION_TRACE(acpi_get_devices);
683 /* Parameter validation */
685 if (!user_function) {
686 return_ACPI_STATUS(AE_BAD_PARAMETER);
690 * We're going to call their callback from OUR callback, so we need
691 * to know what it is, and their context parameter.
694 info.context = context;
695 info.user_function = user_function;
698 * Lock the namespace around the walk.
699 * The namespace will be unlocked/locked around each call
700 * to the user function - since this function
701 * must be allowed to make Acpi calls itself.
703 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
704 if (ACPI_FAILURE(status)) {
705 return_ACPI_STATUS(status);
708 status = acpi_ns_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
709 ACPI_UINT32_MAX, ACPI_NS_WALK_UNLOCK,
710 acpi_ns_get_device_callback, NULL,
711 &info, return_value);
713 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
714 return_ACPI_STATUS(status);
717 ACPI_EXPORT_SYMBOL(acpi_get_devices)
719 /*******************************************************************************
721 * FUNCTION: acpi_attach_data
723 * PARAMETERS: obj_handle - Namespace node
724 * handler - Handler for this attachment
725 * data - Pointer to data to be attached
729 * DESCRIPTION: Attach arbitrary data and handler to a namespace node.
731 ******************************************************************************/
733 acpi_attach_data(acpi_handle obj_handle,
734 acpi_object_handler handler, void *data)
736 struct acpi_namespace_node *node;
739 /* Parameter validation */
741 if (!obj_handle || !handler || !data) {
742 return (AE_BAD_PARAMETER);
745 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
746 if (ACPI_FAILURE(status)) {
750 /* Convert and validate the handle */
752 node = acpi_ns_validate_handle(obj_handle);
754 status = AE_BAD_PARAMETER;
755 goto unlock_and_exit;
758 status = acpi_ns_attach_data(node, handler, data);
761 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
765 ACPI_EXPORT_SYMBOL(acpi_attach_data)
767 /*******************************************************************************
769 * FUNCTION: acpi_detach_data
771 * PARAMETERS: obj_handle - Namespace node handle
772 * handler - Handler used in call to acpi_attach_data
776 * DESCRIPTION: Remove data that was previously attached to a node.
778 ******************************************************************************/
780 acpi_detach_data(acpi_handle obj_handle, acpi_object_handler handler)
782 struct acpi_namespace_node *node;
785 /* Parameter validation */
787 if (!obj_handle || !handler) {
788 return (AE_BAD_PARAMETER);
791 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
792 if (ACPI_FAILURE(status)) {
796 /* Convert and validate the handle */
798 node = acpi_ns_validate_handle(obj_handle);
800 status = AE_BAD_PARAMETER;
801 goto unlock_and_exit;
804 status = acpi_ns_detach_data(node, handler);
807 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
811 ACPI_EXPORT_SYMBOL(acpi_detach_data)
813 /*******************************************************************************
815 * FUNCTION: acpi_get_data
817 * PARAMETERS: obj_handle - Namespace node
818 * handler - Handler used in call to attach_data
819 * data - Where the data is returned
823 * DESCRIPTION: Retrieve data that was previously attached to a namespace node.
825 ******************************************************************************/
827 acpi_get_data(acpi_handle obj_handle, acpi_object_handler handler, void **data)
829 struct acpi_namespace_node *node;
832 /* Parameter validation */
834 if (!obj_handle || !handler || !data) {
835 return (AE_BAD_PARAMETER);
838 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
839 if (ACPI_FAILURE(status)) {
843 /* Convert and validate the handle */
845 node = acpi_ns_validate_handle(obj_handle);
847 status = AE_BAD_PARAMETER;
848 goto unlock_and_exit;
851 status = acpi_ns_get_attached_data(node, handler, data);
854 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
858 ACPI_EXPORT_SYMBOL(acpi_get_data)