1 /*******************************************************************************
3 * Module Name: nsxfeval - Public interfaces to the ACPI subsystem
4 * ACPI Object evaluation interfaces
6 ******************************************************************************/
9 * Copyright (C) 2000 - 2012, 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
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.
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_ns_valid_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
)) {
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 acpica_device_id
*hid
;
546 struct acpica_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
)
619 /* Run _STA to determine if device is present */
621 status
= acpi_ut_execute_STA(node
, &flags
);
622 if (ACPI_FAILURE(status
)) {
623 return (AE_CTRL_DEPTH
);
626 if (!(flags
& ACPI_STA_DEVICE_PRESENT
) &&
627 !(flags
& ACPI_STA_DEVICE_FUNCTIONING
)) {
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.
633 return (AE_CTRL_DEPTH
);
636 /* We have a valid device, invoke the user function */
638 status
= info
->user_function(obj_handle
, nesting_level
, info
->context
,
643 /*******************************************************************************
645 * FUNCTION: acpi_get_devices
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
653 * RETURNS Return value from the user_function if terminated early.
654 * Otherwise, returns NULL.
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.
663 * This is a wrapper for walk_namespace, but the callback performs
664 * additional filtering. Please see acpi_ns_get_device_callback.
666 ******************************************************************************/
669 acpi_get_devices(const char *HID
,
670 acpi_walk_callback user_function
,
671 void *context
, void **return_value
)
674 struct acpi_get_devices_info info
;
676 ACPI_FUNCTION_TRACE(acpi_get_devices
);
678 /* Parameter validation */
680 if (!user_function
) {
681 return_ACPI_STATUS(AE_BAD_PARAMETER
);
685 * We're going to call their callback from OUR callback, so we need
686 * to know what it is, and their context parameter.
689 info
.context
= context
;
690 info
.user_function
= user_function
;
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.
698 status
= acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE
);
699 if (ACPI_FAILURE(status
)) {
700 return_ACPI_STATUS(status
);
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
);
708 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE
);
709 return_ACPI_STATUS(status
);
712 ACPI_EXPORT_SYMBOL(acpi_get_devices
)
714 /*******************************************************************************
716 * FUNCTION: acpi_attach_data
718 * PARAMETERS: obj_handle - Namespace node
719 * Handler - Handler for this attachment
720 * Data - Pointer to data to be attached
724 * DESCRIPTION: Attach arbitrary data and handler to a namespace node.
726 ******************************************************************************/
728 acpi_attach_data(acpi_handle obj_handle
,
729 acpi_object_handler handler
, void *data
)
731 struct acpi_namespace_node
*node
;
734 /* Parameter validation */
736 if (!obj_handle
|| !handler
|| !data
) {
737 return (AE_BAD_PARAMETER
);
740 status
= acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE
);
741 if (ACPI_FAILURE(status
)) {
745 /* Convert and validate the handle */
747 node
= acpi_ns_validate_handle(obj_handle
);
749 status
= AE_BAD_PARAMETER
;
750 goto unlock_and_exit
;
753 status
= acpi_ns_attach_data(node
, handler
, data
);
756 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE
);
760 ACPI_EXPORT_SYMBOL(acpi_attach_data
)
762 /*******************************************************************************
764 * FUNCTION: acpi_detach_data
766 * PARAMETERS: obj_handle - Namespace node handle
767 * Handler - Handler used in call to acpi_attach_data
771 * DESCRIPTION: Remove data that was previously attached to a node.
773 ******************************************************************************/
775 acpi_detach_data(acpi_handle obj_handle
, acpi_object_handler handler
)
777 struct acpi_namespace_node
*node
;
780 /* Parameter validation */
782 if (!obj_handle
|| !handler
) {
783 return (AE_BAD_PARAMETER
);
786 status
= acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE
);
787 if (ACPI_FAILURE(status
)) {
791 /* Convert and validate the handle */
793 node
= acpi_ns_validate_handle(obj_handle
);
795 status
= AE_BAD_PARAMETER
;
796 goto unlock_and_exit
;
799 status
= acpi_ns_detach_data(node
, handler
);
802 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE
);
806 ACPI_EXPORT_SYMBOL(acpi_detach_data
)
808 /*******************************************************************************
810 * FUNCTION: acpi_get_data
812 * PARAMETERS: obj_handle - Namespace node
813 * Handler - Handler used in call to attach_data
814 * Data - Where the data is returned
818 * DESCRIPTION: Retrieve data that was previously attached to a namespace node.
820 ******************************************************************************/
822 acpi_get_data(acpi_handle obj_handle
, acpi_object_handler handler
, void **data
)
824 struct acpi_namespace_node
*node
;
827 /* Parameter validation */
829 if (!obj_handle
|| !handler
|| !data
) {
830 return (AE_BAD_PARAMETER
);
833 status
= acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE
);
834 if (ACPI_FAILURE(status
)) {
838 /* Convert and validate the handle */
840 node
= acpi_ns_validate_handle(obj_handle
);
842 status
= AE_BAD_PARAMETER
;
843 goto unlock_and_exit
;
846 status
= acpi_ns_get_attached_data(node
, handler
, data
);
849 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE
);
853 ACPI_EXPORT_SYMBOL(acpi_get_data
)