Linux Audio

Check our new training course

Loading...
v3.1
  1/*******************************************************************************
  2 *
  3 * Module Name: nsxfeval - Public interfaces to the ACPI subsystem
  4 *                         ACPI Object evaluation interfaces
  5 *
  6 ******************************************************************************/
  7
  8/*
  9 * Copyright (C) 2000 - 2011, Intel Corp.
 10 * All rights reserved.
 11 *
 12 * Redistribution and use in source and binary forms, with or without
 13 * modification, are permitted provided that the following conditions
 14 * are met:
 15 * 1. Redistributions of source code must retain the above copyright
 16 *    notice, this list of conditions, and the following disclaimer,
 17 *    without modification.
 18 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 19 *    substantially similar to the "NO WARRANTY" disclaimer below
 20 *    ("Disclaimer") and any redistribution must be conditioned upon
 21 *    including a substantially similar Disclaimer requirement for further
 22 *    binary redistribution.
 23 * 3. Neither the names of the above-listed copyright holders nor the names
 24 *    of any contributors may be used to endorse or promote products derived
 25 *    from this software without specific prior written permission.
 26 *
 27 * Alternatively, this software may be distributed under the terms of the
 28 * GNU General Public License ("GPL") version 2 as published by the Free
 29 * Software Foundation.
 30 *
 31 * NO WARRANTY
 32 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 33 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 34 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
 35 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 36 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 37 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 38 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 39 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 40 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 41 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 42 * POSSIBILITY OF SUCH DAMAGES.
 43 */
 44
 
 
 45#include <acpi/acpi.h>
 46#include "accommon.h"
 47#include "acnamesp.h"
 48#include "acinterp.h"
 49
 50#define _COMPONENT          ACPI_NAMESPACE
 51ACPI_MODULE_NAME("nsxfeval")
 52
 53/* Local prototypes */
 54static void acpi_ns_resolve_references(struct acpi_evaluate_info *info);
 55
 56/*******************************************************************************
 57 *
 58 * FUNCTION:    acpi_evaluate_object_typed
 59 *
 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
 68 *
 69 * RETURN:      Status
 70 *
 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)
 74 *
 75 ******************************************************************************/
 76
 77acpi_status
 78acpi_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)
 83{
 84	acpi_status status;
 85	u8 must_free = FALSE;
 86
 87	ACPI_FUNCTION_TRACE(acpi_evaluate_object_typed);
 88
 89	/* Return buffer must be valid */
 90
 91	if (!return_buffer) {
 92		return_ACPI_STATUS(AE_BAD_PARAMETER);
 93	}
 94
 95	if (return_buffer->length == ACPI_ALLOCATE_BUFFER) {
 96		must_free = TRUE;
 97	}
 98
 99	/* Evaluate the object */
100
101	status =
102	    acpi_evaluate_object(handle, pathname, external_params,
103				 return_buffer);
104	if (ACPI_FAILURE(status)) {
105		return_ACPI_STATUS(status);
106	}
107
108	/* Type ANY means "don't care" */
109
110	if (return_type == ACPI_TYPE_ANY) {
111		return_ACPI_STATUS(AE_OK);
112	}
113
114	if (return_buffer->length == 0) {
115
116		/* Error because caller specifically asked for a return value */
117
118		ACPI_ERROR((AE_INFO, "No return value"));
119		return_ACPI_STATUS(AE_NULL_OBJECT);
120	}
121
122	/* Examine the object type returned from evaluate_object */
123
124	if (((union acpi_object *)return_buffer->pointer)->type == return_type) {
125		return_ACPI_STATUS(AE_OK);
126	}
127
128	/* Return object type does not match requested type */
129
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)));
135
136	if (must_free) {
137
138		/* Caller used ACPI_ALLOCATE_BUFFER, free the return buffer */
139
140		ACPI_FREE(return_buffer->pointer);
 
 
 
 
141		return_buffer->pointer = NULL;
142	}
143
144	return_buffer->length = 0;
145	return_ACPI_STATUS(AE_TYPE);
146}
147
148ACPI_EXPORT_SYMBOL(acpi_evaluate_object_typed)
149
150/*******************************************************************************
151 *
152 * FUNCTION:    acpi_evaluate_object
153 *
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.
161 *
162 * RETURN:      Status
163 *
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)
167 *
168 ******************************************************************************/
169acpi_status
170acpi_evaluate_object(acpi_handle handle,
171		     acpi_string pathname,
172		     struct acpi_object_list *external_params,
173		     struct acpi_buffer *return_buffer)
174{
175	acpi_status status;
176	struct acpi_evaluate_info *info;
177	acpi_size buffer_space_needed;
178	u32 i;
179
180	ACPI_FUNCTION_TRACE(acpi_evaluate_object);
181
182	/* Allocate and initialize the evaluation information block */
183
184	info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
185	if (!info) {
186		return_ACPI_STATUS(AE_NO_MEMORY);
187	}
188
189	info->pathname = pathname;
190
191	/* Convert and validate the device handle */
192
193	info->prefix_node = acpi_ns_validate_handle(handle);
194	if (!info->prefix_node) {
195		status = AE_BAD_PARAMETER;
196		goto cleanup;
197	}
198
199	/*
200	 * If there are parameters to be passed to a control method, the external
201	 * objects must all be converted to internal objects
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
202	 */
203	if (external_params && external_params->count) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
204		/*
205		 * Allocate a new parameter block for the internal objects
206		 * Add 1 to count to allow for null terminated internal list
207		 */
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;
215		}
216
217		/* Convert each external object in the list to an internal object */
218
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;
227			}
228		}
229		info->parameters[external_params->count] = NULL;
 
230	}
231
 
 
232	/*
233	 * Three major cases:
234	 * 1) Fully qualified pathname
235	 * 2) No handle, not fully qualified pathname (error)
236	 * 3) Valid handle
237	 */
238	if ((pathname) && (acpi_ns_valid_root_prefix(pathname[0]))) {
 
239
240		/* The path is fully qualified, just evaluate by name */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
241
242		info->prefix_node = NULL;
243		status = acpi_ns_evaluate(info);
244	} else if (!handle) {
245		/*
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
249		 */
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));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
257		}
 
258
259		status = AE_BAD_PARAMETER;
260	} else {
261		/* We have a namespace a node and a possible relative path */
262
263		status = acpi_ns_evaluate(info);
 
 
 
 
 
 
 
264	}
265
 
 
 
 
 
 
266	/*
267	 * If we are expecting a return value, and all went well above,
268	 * copy the return value to an external object.
269	 */
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) {
276				/*
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.
283				 */
284				status = AE_TYPE;
285				info->return_object = NULL;	/* No need to delete a NS Node */
286				return_buffer->length = 0;
287			}
288
289			if (ACPI_SUCCESS(status)) {
 
 
 
 
 
 
 
 
 
 
 
 
 
290
291				/* Dereference Index and ref_of references */
 
 
292
293				acpi_ns_resolve_references(info);
294
295				/* Get the size of the returned object */
296
297				status =
298				    acpi_ut_get_object_size(info->return_object,
299							    &buffer_space_needed);
300				if (ACPI_SUCCESS(status)) {
301
302					/* Validate/Allocate/Clear caller buffer */
303
304					status =
305					    acpi_ut_initialize_buffer
306					    (return_buffer,
307					     buffer_space_needed);
308					if (ACPI_FAILURE(status)) {
309						/*
310						 * Caller's buffer is too small or a new one can't
311						 * be allocated
312						 */
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 */
321
322						status =
323						    acpi_ut_copy_iobject_to_eobject
324						    (info->return_object,
325						     return_buffer);
326					}
327				}
328			}
329		}
330	}
331
 
 
332	if (info->return_object) {
333		/*
334		 * Delete the internal return object. NOTE: Interpreter must be
335		 * locked to avoid race condition.
336		 */
337		acpi_ex_enter_interpreter();
338
339		/* Remove one reference on the return object (should delete it) */
340
341		acpi_ut_remove_reference(info->return_object);
342		acpi_ex_exit_interpreter();
343	}
344
345      cleanup:
346
347	/* Free the input parameter list (if we created one) */
348
349	if (info->parameters) {
350
351		/* Free the allocated parameter block */
352
353		acpi_ut_delete_internal_object_list(info->parameters);
354	}
355
356	ACPI_FREE(info);
357	return_ACPI_STATUS(status);
358}
359
360ACPI_EXPORT_SYMBOL(acpi_evaluate_object)
361
362/*******************************************************************************
363 *
364 * FUNCTION:    acpi_ns_resolve_references
365 *
366 * PARAMETERS:  Info                    - Evaluation info block
367 *
368 * RETURN:      Info->return_object is replaced with the dereferenced object
369 *
370 * DESCRIPTION: Dereference certain reference objects. Called before an
371 *              internal return object is converted to an external union acpi_object.
372 *
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.
377 *
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.
380 *
381 ******************************************************************************/
382static void acpi_ns_resolve_references(struct acpi_evaluate_info *info)
383{
384	union acpi_operand_object *obj_desc = NULL;
385	struct acpi_namespace_node *node;
386
387	/* We are interested in reference objects only */
388
389	if ((info->return_object)->common.type != ACPI_TYPE_LOCAL_REFERENCE) {
390		return;
391	}
392
393	/*
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.
399	 */
400	switch (info->return_object->reference.class) {
401	case ACPI_REFCLASS_INDEX:
402
403		obj_desc = *(info->return_object->reference.where);
404		break;
405
406	case ACPI_REFCLASS_REFOF:
407
408		node = info->return_object->reference.object;
409		if (node) {
410			obj_desc = node->object;
411		}
412		break;
413
414	default:
 
415		return;
416	}
417
418	/* Replace the existing reference object */
419
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;
424	}
425
426	return;
427}
428
429/*******************************************************************************
430 *
431 * FUNCTION:    acpi_walk_namespace
432 *
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 *              pre_order_visit     - Called during tree pre-order visit
437 *                                    when an object of "Type" is found
438 *              post_order_visit    - Called during tree post-order visit
439 *                                    when an object of "Type" is found
440 *              Context             - Passed to user function(s) above
441 *              return_value        - Location where return value of
442 *                                    user_function is put if terminated early
443 *
444 * RETURNS      Return value from the user_function if terminated early.
445 *              Otherwise, returns NULL.
446 *
447 * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
448 *              starting (and ending) at the object specified by start_handle.
449 *              The callback function is called whenever an object that matches
450 *              the type parameter is found. If the callback function returns
451 *              a non-zero value, the search is terminated immediately and this
452 *              value is returned to the caller.
453 *
454 *              The point of this procedure is to provide a generic namespace
455 *              walk routine that can be called from multiple places to
456 *              provide multiple services; the callback function(s) can be
457 *              tailored to each task, whether it is a print function,
458 *              a compare function, etc.
459 *
460 ******************************************************************************/
461
462acpi_status
463acpi_walk_namespace(acpi_object_type type,
464		    acpi_handle start_object,
465		    u32 max_depth,
466		    acpi_walk_callback pre_order_visit,
467		    acpi_walk_callback post_order_visit,
468		    void *context, void **return_value)
469{
470	acpi_status status;
471
472	ACPI_FUNCTION_TRACE(acpi_walk_namespace);
473
474	/* Parameter validation */
475
476	if ((type > ACPI_TYPE_LOCAL_MAX) ||
477	    (!max_depth) || (!pre_order_visit && !post_order_visit)) {
478		return_ACPI_STATUS(AE_BAD_PARAMETER);
479	}
480
481	/*
482	 * Need to acquire the namespace reader lock to prevent interference
483	 * with any concurrent table unloads (which causes the deletion of
484	 * namespace objects). We cannot allow the deletion of a namespace node
485	 * while the user function is using it. The exception to this are the
486	 * nodes created and deleted during control method execution -- these
487	 * nodes are marked as temporary nodes and are ignored by the namespace
488	 * walk. Thus, control methods can be executed while holding the
489	 * namespace deletion lock (and the user function can execute control
490	 * methods.)
491	 */
492	status = acpi_ut_acquire_read_lock(&acpi_gbl_namespace_rw_lock);
493	if (ACPI_FAILURE(status)) {
494		return status;
495	}
496
497	/*
498	 * Lock the namespace around the walk. The namespace will be
499	 * unlocked/locked around each call to the user function - since the user
500	 * function must be allowed to make ACPICA calls itself (for example, it
501	 * will typically execute control methods during device enumeration.)
502	 */
503	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
504	if (ACPI_FAILURE(status)) {
505		goto unlock_and_exit;
506	}
507
 
 
 
 
 
 
 
508	status = acpi_ns_walk_namespace(type, start_object, max_depth,
509					ACPI_NS_WALK_UNLOCK, pre_order_visit,
510					post_order_visit, context,
511					return_value);
512
 
513	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
514
515      unlock_and_exit:
516	(void)acpi_ut_release_read_lock(&acpi_gbl_namespace_rw_lock);
517	return_ACPI_STATUS(status);
518}
519
520ACPI_EXPORT_SYMBOL(acpi_walk_namespace)
521
522/*******************************************************************************
523 *
524 * FUNCTION:    acpi_ns_get_device_callback
525 *
526 * PARAMETERS:  Callback from acpi_get_device
527 *
528 * RETURN:      Status
529 *
530 * DESCRIPTION: Takes callbacks from walk_namespace and filters out all non-
531 *              present devices, or if they specified a HID, it filters based
532 *              on that.
533 *
534 ******************************************************************************/
535static acpi_status
536acpi_ns_get_device_callback(acpi_handle obj_handle,
537			    u32 nesting_level,
538			    void *context, void **return_value)
539{
540	struct acpi_get_devices_info *info = context;
541	acpi_status status;
542	struct acpi_namespace_node *node;
543	u32 flags;
544	struct acpica_device_id *hid;
545	struct acpica_device_id_list *cid;
546	u32 i;
547	u8 found;
548	int no_match;
549
550	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
551	if (ACPI_FAILURE(status)) {
552		return (status);
553	}
554
555	node = acpi_ns_validate_handle(obj_handle);
556	status = acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
557	if (ACPI_FAILURE(status)) {
558		return (status);
559	}
560
561	if (!node) {
562		return (AE_BAD_PARAMETER);
563	}
564
565	/*
566	 * First, filter based on the device HID and CID.
567	 *
568	 * 01/2010: For this case where a specific HID is requested, we don't
569	 * want to run _STA until we have an actual HID match. Thus, we will
570	 * not unnecessarily execute _STA on devices for which the caller
571	 * doesn't care about. Previously, _STA was executed unconditionally
572	 * on all devices found here.
573	 *
574	 * A side-effect of this change is that now we will continue to search
575	 * for a matching HID even under device trees where the parent device
576	 * would have returned a _STA that indicates it is not present or
577	 * not functioning (thus aborting the search on that branch).
578	 */
579	if (info->hid != NULL) {
580		status = acpi_ut_execute_HID(node, &hid);
581		if (status == AE_NOT_FOUND) {
582			return (AE_OK);
583		} else if (ACPI_FAILURE(status)) {
584			return (AE_CTRL_DEPTH);
585		}
586
587		no_match = ACPI_STRCMP(hid->string, info->hid);
588		ACPI_FREE(hid);
589
590		if (no_match) {
591			/*
592			 * HID does not match, attempt match within the
593			 * list of Compatible IDs (CIDs)
594			 */
595			status = acpi_ut_execute_CID(node, &cid);
596			if (status == AE_NOT_FOUND) {
597				return (AE_OK);
598			} else if (ACPI_FAILURE(status)) {
599				return (AE_CTRL_DEPTH);
600			}
601
602			/* Walk the CID list */
603
604			found = 0;
605			for (i = 0; i < cid->count; i++) {
606				if (ACPI_STRCMP(cid->ids[i].string, info->hid)
607				    == 0) {
608					found = 1;
 
 
609					break;
610				}
611			}
 
612			ACPI_FREE(cid);
613			if (!found)
614				return (AE_OK);
 
615		}
616	}
617
618	/* Run _STA to determine if device is present */
619
620	status = acpi_ut_execute_STA(node, &flags);
621	if (ACPI_FAILURE(status)) {
622		return (AE_CTRL_DEPTH);
623	}
624
625	if (!(flags & ACPI_STA_DEVICE_PRESENT) &&
626	    !(flags & ACPI_STA_DEVICE_FUNCTIONING)) {
627		/*
628		 * Don't examine the children of the device only when the
629		 * device is neither present nor functional. See ACPI spec,
630		 * description of _STA for more information.
631		 */
632		return (AE_CTRL_DEPTH);
633	}
634
635	/* We have a valid device, invoke the user function */
636
637	status = info->user_function(obj_handle, nesting_level, info->context,
638				     return_value);
639	return (status);
640}
641
642/*******************************************************************************
643 *
644 * FUNCTION:    acpi_get_devices
645 *
646 * PARAMETERS:  HID                 - HID to search for. Can be NULL.
647 *              user_function       - Called when a matching object is found
648 *              Context             - Passed to user function
649 *              return_value        - Location where return value of
650 *                                    user_function is put if terminated early
651 *
652 * RETURNS      Return value from the user_function if terminated early.
653 *              Otherwise, returns NULL.
654 *
655 * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
656 *              starting (and ending) at the object specified by start_handle.
657 *              The user_function is called whenever an object of type
658 *              Device is found.  If the user function returns
659 *              a non-zero value, the search is terminated immediately and this
660 *              value is returned to the caller.
661 *
662 *              This is a wrapper for walk_namespace, but the callback performs
663 *              additional filtering. Please see acpi_ns_get_device_callback.
664 *
665 ******************************************************************************/
666
667acpi_status
668acpi_get_devices(const char *HID,
669		 acpi_walk_callback user_function,
670		 void *context, void **return_value)
671{
672	acpi_status status;
673	struct acpi_get_devices_info info;
674
675	ACPI_FUNCTION_TRACE(acpi_get_devices);
676
677	/* Parameter validation */
678
679	if (!user_function) {
680		return_ACPI_STATUS(AE_BAD_PARAMETER);
681	}
682
683	/*
684	 * We're going to call their callback from OUR callback, so we need
685	 * to know what it is, and their context parameter.
686	 */
687	info.hid = HID;
688	info.context = context;
689	info.user_function = user_function;
690
691	/*
692	 * Lock the namespace around the walk.
693	 * The namespace will be unlocked/locked around each call
694	 * to the user function - since this function
695	 * must be allowed to make Acpi calls itself.
696	 */
697	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
698	if (ACPI_FAILURE(status)) {
699		return_ACPI_STATUS(status);
700	}
701
702	status = acpi_ns_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
703					ACPI_UINT32_MAX, ACPI_NS_WALK_UNLOCK,
704					acpi_ns_get_device_callback, NULL,
705					&info, return_value);
706
707	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
708	return_ACPI_STATUS(status);
709}
710
711ACPI_EXPORT_SYMBOL(acpi_get_devices)
712
713/*******************************************************************************
714 *
715 * FUNCTION:    acpi_attach_data
716 *
717 * PARAMETERS:  obj_handle          - Namespace node
718 *              Handler             - Handler for this attachment
719 *              Data                - Pointer to data to be attached
720 *
721 * RETURN:      Status
722 *
723 * DESCRIPTION: Attach arbitrary data and handler to a namespace node.
724 *
725 ******************************************************************************/
726acpi_status
727acpi_attach_data(acpi_handle obj_handle,
728		 acpi_object_handler handler, void *data)
729{
730	struct acpi_namespace_node *node;
731	acpi_status status;
732
733	/* Parameter validation */
734
735	if (!obj_handle || !handler || !data) {
736		return (AE_BAD_PARAMETER);
737	}
738
739	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
740	if (ACPI_FAILURE(status)) {
741		return (status);
742	}
743
744	/* Convert and validate the handle */
745
746	node = acpi_ns_validate_handle(obj_handle);
747	if (!node) {
748		status = AE_BAD_PARAMETER;
749		goto unlock_and_exit;
750	}
751
752	status = acpi_ns_attach_data(node, handler, data);
753
754      unlock_and_exit:
755	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
756	return (status);
757}
758
759ACPI_EXPORT_SYMBOL(acpi_attach_data)
760
761/*******************************************************************************
762 *
763 * FUNCTION:    acpi_detach_data
764 *
765 * PARAMETERS:  obj_handle          - Namespace node handle
766 *              Handler             - Handler used in call to acpi_attach_data
767 *
768 * RETURN:      Status
769 *
770 * DESCRIPTION: Remove data that was previously attached to a node.
771 *
772 ******************************************************************************/
773acpi_status
774acpi_detach_data(acpi_handle obj_handle, acpi_object_handler handler)
775{
776	struct acpi_namespace_node *node;
777	acpi_status status;
778
779	/* Parameter validation */
780
781	if (!obj_handle || !handler) {
782		return (AE_BAD_PARAMETER);
783	}
784
785	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
786	if (ACPI_FAILURE(status)) {
787		return (status);
788	}
789
790	/* Convert and validate the handle */
791
792	node = acpi_ns_validate_handle(obj_handle);
793	if (!node) {
794		status = AE_BAD_PARAMETER;
795		goto unlock_and_exit;
796	}
797
798	status = acpi_ns_detach_data(node, handler);
799
800      unlock_and_exit:
801	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
802	return (status);
803}
804
805ACPI_EXPORT_SYMBOL(acpi_detach_data)
806
807/*******************************************************************************
808 *
809 * FUNCTION:    acpi_get_data
810 *
811 * PARAMETERS:  obj_handle          - Namespace node
812 *              Handler             - Handler used in call to attach_data
813 *              Data                - Where the data is returned
 
814 *
815 * RETURN:      Status
816 *
817 * DESCRIPTION: Retrieve data that was previously attached to a namespace node.
 
818 *
819 ******************************************************************************/
820acpi_status
821acpi_get_data(acpi_handle obj_handle, acpi_object_handler handler, void **data)
 
822{
823	struct acpi_namespace_node *node;
824	acpi_status status;
825
826	/* Parameter validation */
827
828	if (!obj_handle || !handler || !data) {
829		return (AE_BAD_PARAMETER);
830	}
831
832	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
833	if (ACPI_FAILURE(status)) {
834		return (status);
835	}
836
837	/* Convert and validate the handle */
838
839	node = acpi_ns_validate_handle(obj_handle);
840	if (!node) {
841		status = AE_BAD_PARAMETER;
842		goto unlock_and_exit;
843	}
844
845	status = acpi_ns_get_attached_data(node, handler, data);
 
 
 
846
847      unlock_and_exit:
848	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
849	return (status);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
850}
851
852ACPI_EXPORT_SYMBOL(acpi_get_data)
v4.10.11
  1/*******************************************************************************
  2 *
  3 * Module Name: nsxfeval - Public interfaces to the ACPI subsystem
  4 *                         ACPI Object evaluation interfaces
  5 *
  6 ******************************************************************************/
  7
  8/*
  9 * Copyright (C) 2000 - 2016, Intel Corp.
 10 * All rights reserved.
 11 *
 12 * Redistribution and use in source and binary forms, with or without
 13 * modification, are permitted provided that the following conditions
 14 * are met:
 15 * 1. Redistributions of source code must retain the above copyright
 16 *    notice, this list of conditions, and the following disclaimer,
 17 *    without modification.
 18 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 19 *    substantially similar to the "NO WARRANTY" disclaimer below
 20 *    ("Disclaimer") and any redistribution must be conditioned upon
 21 *    including a substantially similar Disclaimer requirement for further
 22 *    binary redistribution.
 23 * 3. Neither the names of the above-listed copyright holders nor the names
 24 *    of any contributors may be used to endorse or promote products derived
 25 *    from this software without specific prior written permission.
 26 *
 27 * Alternatively, this software may be distributed under the terms of the
 28 * GNU General Public License ("GPL") version 2 as published by the Free
 29 * Software Foundation.
 30 *
 31 * NO WARRANTY
 32 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 33 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 34 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
 35 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 36 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 37 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 38 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 39 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 40 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 41 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 42 * POSSIBILITY OF SUCH DAMAGES.
 43 */
 44
 45#define EXPORT_ACPI_INTERFACES
 46
 47#include <acpi/acpi.h>
 48#include "accommon.h"
 49#include "acnamesp.h"
 50#include "acinterp.h"
 51
 52#define _COMPONENT          ACPI_NAMESPACE
 53ACPI_MODULE_NAME("nsxfeval")
 54
 55/* Local prototypes */
 56static void acpi_ns_resolve_references(struct acpi_evaluate_info *info);
 57
 58/*******************************************************************************
 59 *
 60 * FUNCTION:    acpi_evaluate_object_typed
 61 *
 62 * PARAMETERS:  handle              - Object handle (optional)
 63 *              pathname            - Object pathname (optional)
 64 *              external_params     - List of parameters to pass to method,
 65 *                                    terminated by NULL. May be NULL
 66 *                                    if no parameters are being passed.
 67 *              return_buffer       - Where to put method's return value (if
 68 *                                    any). If NULL, no value is returned.
 69 *              return_type         - Expected type of return object
 70 *
 71 * RETURN:      Status
 72 *
 73 * DESCRIPTION: Find and evaluate the given object, passing the given
 74 *              parameters if necessary. One of "Handle" or "Pathname" must
 75 *              be valid (non-null)
 76 *
 77 ******************************************************************************/
 78
 79acpi_status
 80acpi_evaluate_object_typed(acpi_handle handle,
 81			   acpi_string pathname,
 82			   struct acpi_object_list *external_params,
 83			   struct acpi_buffer *return_buffer,
 84			   acpi_object_type return_type)
 85{
 86	acpi_status status;
 87	u8 free_buffer_on_error = FALSE;
 88
 89	ACPI_FUNCTION_TRACE(acpi_evaluate_object_typed);
 90
 91	/* Return buffer must be valid */
 92
 93	if (!return_buffer) {
 94		return_ACPI_STATUS(AE_BAD_PARAMETER);
 95	}
 96
 97	if (return_buffer->length == ACPI_ALLOCATE_BUFFER) {
 98		free_buffer_on_error = TRUE;
 99	}
100
101	/* Evaluate the object */
102
103	status = acpi_evaluate_object(handle, pathname,
104				      external_params, return_buffer);
 
105	if (ACPI_FAILURE(status)) {
106		return_ACPI_STATUS(status);
107	}
108
109	/* Type ANY means "don't care" */
110
111	if (return_type == ACPI_TYPE_ANY) {
112		return_ACPI_STATUS(AE_OK);
113	}
114
115	if (return_buffer->length == 0) {
116
117		/* Error because caller specifically asked for a return value */
118
119		ACPI_ERROR((AE_INFO, "No return value"));
120		return_ACPI_STATUS(AE_NULL_OBJECT);
121	}
122
123	/* Examine the object type returned from evaluate_object */
124
125	if (((union acpi_object *)return_buffer->pointer)->type == return_type) {
126		return_ACPI_STATUS(AE_OK);
127	}
128
129	/* Return object type does not match requested type */
130
131	ACPI_ERROR((AE_INFO,
132		    "Incorrect return type [%s] requested [%s]",
133		    acpi_ut_get_type_name(((union acpi_object *)return_buffer->
134					   pointer)->type),
135		    acpi_ut_get_type_name(return_type)));
136
137	if (free_buffer_on_error) {
138		/*
139		 * Free a buffer created via ACPI_ALLOCATE_BUFFER.
140		 * Note: We use acpi_os_free here because acpi_os_allocate was used
141		 * to allocate the buffer. This purposefully bypasses the
142		 * (optionally enabled) allocation tracking mechanism since we
143		 * only want to track internal allocations.
144		 */
145		acpi_os_free(return_buffer->pointer);
146		return_buffer->pointer = NULL;
147	}
148
149	return_buffer->length = 0;
150	return_ACPI_STATUS(AE_TYPE);
151}
152
153ACPI_EXPORT_SYMBOL(acpi_evaluate_object_typed)
154
155/*******************************************************************************
156 *
157 * FUNCTION:    acpi_evaluate_object
158 *
159 * PARAMETERS:  handle              - Object handle (optional)
160 *              pathname            - Object pathname (optional)
161 *              external_params     - List of parameters to pass to method,
162 *                                    terminated by NULL. May be NULL
163 *                                    if no parameters are being passed.
164 *              return_buffer       - Where to put method's return value (if
165 *                                    any). If NULL, no value is returned.
166 *
167 * RETURN:      Status
168 *
169 * DESCRIPTION: Find and evaluate the given object, passing the given
170 *              parameters if necessary. One of "Handle" or "Pathname" must
171 *              be valid (non-null)
172 *
173 ******************************************************************************/
174acpi_status
175acpi_evaluate_object(acpi_handle handle,
176		     acpi_string pathname,
177		     struct acpi_object_list *external_params,
178		     struct acpi_buffer *return_buffer)
179{
180	acpi_status status;
181	struct acpi_evaluate_info *info;
182	acpi_size buffer_space_needed;
183	u32 i;
184
185	ACPI_FUNCTION_TRACE(acpi_evaluate_object);
186
187	/* Allocate and initialize the evaluation information block */
188
189	info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
190	if (!info) {
191		return_ACPI_STATUS(AE_NO_MEMORY);
192	}
193
 
 
194	/* Convert and validate the device handle */
195
196	info->prefix_node = acpi_ns_validate_handle(handle);
197	if (!info->prefix_node) {
198		status = AE_BAD_PARAMETER;
199		goto cleanup;
200	}
201
202	/*
203	 * Get the actual namespace node for the target object.
204	 * Handles these cases:
205	 *
206	 * 1) Null node, valid pathname from root (absolute path)
207	 * 2) Node and valid pathname (path relative to Node)
208	 * 3) Node, Null pathname
209	 */
210	if ((pathname) && (ACPI_IS_ROOT_PREFIX(pathname[0]))) {
211
212		/* The path is fully qualified, just evaluate by name */
213
214		info->prefix_node = NULL;
215	} else if (!handle) {
216		/*
217		 * A handle is optional iff a fully qualified pathname is specified.
218		 * Since we've already handled fully qualified names above, this is
219		 * an error.
220		 */
221		if (!pathname) {
222			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
223					  "Both Handle and Pathname are NULL"));
224		} else {
225			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
226					  "Null Handle with relative pathname [%s]",
227					  pathname));
228		}
229
230		status = AE_BAD_PARAMETER;
231		goto cleanup;
232	}
233
234	info->relative_pathname = pathname;
235
236	/*
237	 * Convert all external objects passed as arguments to the
238	 * internal version(s).
239	 */
240	if (external_params && external_params->count) {
241		info->param_count = (u16)external_params->count;
242
243		/* Warn on impossible argument count */
244
245		if (info->param_count > ACPI_METHOD_NUM_ARGS) {
246			ACPI_WARN_PREDEFINED((AE_INFO, pathname,
247					      ACPI_WARN_ALWAYS,
248					      "Excess arguments (%u) - using only %u",
249					      info->param_count,
250					      ACPI_METHOD_NUM_ARGS));
251
252			info->param_count = ACPI_METHOD_NUM_ARGS;
253		}
254
255		/*
256		 * Allocate a new parameter block for the internal objects
257		 * Add 1 to count to allow for null terminated internal list
258		 */
259		info->parameters = ACPI_ALLOCATE_ZEROED(((acpi_size)info->
260							 param_count +
 
261							 1) * sizeof(void *));
262		if (!info->parameters) {
263			status = AE_NO_MEMORY;
264			goto cleanup;
265		}
266
267		/* Convert each external object in the list to an internal object */
268
269		for (i = 0; i < info->param_count; i++) {
270			status =
271			    acpi_ut_copy_eobject_to_iobject(&external_params->
272							    pointer[i],
273							    &info->
274							    parameters[i]);
275			if (ACPI_FAILURE(status)) {
276				goto cleanup;
277			}
278		}
279
280		info->parameters[info->param_count] = NULL;
281	}
282
283#ifdef _FUTURE_FEATURE
284
285	/*
286	 * Begin incoming argument count analysis. Check for too few args
287	 * and too many args.
 
 
288	 */
289	switch (acpi_ns_get_type(info->node)) {
290	case ACPI_TYPE_METHOD:
291
292		/* Check incoming argument count against the method definition */
293
294		if (info->obj_desc->method.param_count > info->param_count) {
295			ACPI_ERROR((AE_INFO,
296				    "Insufficient arguments (%u) - %u are required",
297				    info->param_count,
298				    info->obj_desc->method.param_count));
299
300			status = AE_MISSING_ARGUMENTS;
301			goto cleanup;
302		}
303
304		else if (info->obj_desc->method.param_count < info->param_count) {
305			ACPI_WARNING((AE_INFO,
306				      "Excess arguments (%u) - only %u are required",
307				      info->param_count,
308				      info->obj_desc->method.param_count));
309
310			/* Just pass the required number of arguments */
311
312			info->param_count = info->obj_desc->method.param_count;
313		}
314
 
 
 
315		/*
316		 * Any incoming external objects to be passed as arguments to the
317		 * method must be converted to internal objects
 
318		 */
319		if (info->param_count) {
320			/*
321			 * Allocate a new parameter block for the internal objects
322			 * Add 1 to count to allow for null terminated internal list
323			 */
324			info->parameters = ACPI_ALLOCATE_ZEROED(((acpi_size)
325								 info->
326								 param_count +
327								 1) *
328								sizeof(void *));
329			if (!info->parameters) {
330				status = AE_NO_MEMORY;
331				goto cleanup;
332			}
333
334			/* Convert each external object in the list to an internal object */
335
336			for (i = 0; i < info->param_count; i++) {
337				status =
338				    acpi_ut_copy_eobject_to_iobject
339				    (&external_params->pointer[i],
340				     &info->parameters[i]);
341				if (ACPI_FAILURE(status)) {
342					goto cleanup;
343				}
344			}
345
346			info->parameters[info->param_count] = NULL;
347		}
348		break;
349
350	default:
 
 
351
352		/* Warn if arguments passed to an object that is not a method */
353
354		if (info->param_count) {
355			ACPI_WARNING((AE_INFO,
356				      "%u arguments were passed to a non-method ACPI object",
357				      info->param_count));
358		}
359		break;
360	}
361
362#endif
363
364	/* Now we can evaluate the object */
365
366	status = acpi_ns_evaluate(info);
367
368	/*
369	 * If we are expecting a return value, and all went well above,
370	 * copy the return value to an external object.
371	 */
372	if (!return_buffer) {
373		goto cleanup_return_object;
374	}
375
376	if (!info->return_object) {
377		return_buffer->length = 0;
378		goto cleanup;
379	}
 
 
 
 
 
 
 
 
 
 
380
381	if (ACPI_GET_DESCRIPTOR_TYPE(info->return_object) ==
382	    ACPI_DESC_TYPE_NAMED) {
383		/*
384		 * If we received a NS Node as a return object, this means that
385		 * the object we are evaluating has nothing interesting to
386		 * return (such as a mutex, etc.)  We return an error because
387		 * these types are essentially unsupported by this interface.
388		 * We don't check up front because this makes it easier to add
389		 * support for various types at a later date if necessary.
390		 */
391		status = AE_TYPE;
392		info->return_object = NULL;	/* No need to delete a NS Node */
393		return_buffer->length = 0;
394	}
395
396	if (ACPI_FAILURE(status)) {
397		goto cleanup_return_object;
398	}
399
400	/* Dereference Index and ref_of references */
401
402	acpi_ns_resolve_references(info);
403
404	/* Get the size of the returned object */
405
406	status = acpi_ut_get_object_size(info->return_object,
407					 &buffer_space_needed);
408	if (ACPI_SUCCESS(status)) {
409
410		/* Validate/Allocate/Clear caller buffer */
411
412		status = acpi_ut_initialize_buffer(return_buffer,
413						   buffer_space_needed);
414		if (ACPI_FAILURE(status)) {
415			/*
416			 * Caller's buffer is too small or a new one can't
417			 * be allocated
418			 */
419			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
420					  "Needed buffer size %X, %s\n",
421					  (u32)buffer_space_needed,
422					  acpi_format_exception(status)));
423		} else {
424			/* We have enough space for the object, build it */
425
426			status =
427			    acpi_ut_copy_iobject_to_eobject(info->return_object,
428							    return_buffer);
 
 
 
 
 
 
 
429		}
430	}
431
432cleanup_return_object:
433
434	if (info->return_object) {
435		/*
436		 * Delete the internal return object. NOTE: Interpreter must be
437		 * locked to avoid race condition.
438		 */
439		acpi_ex_enter_interpreter();
440
441		/* Remove one reference on the return object (should delete it) */
442
443		acpi_ut_remove_reference(info->return_object);
444		acpi_ex_exit_interpreter();
445	}
446
447cleanup:
448
449	/* Free the input parameter list (if we created one) */
450
451	if (info->parameters) {
452
453		/* Free the allocated parameter block */
454
455		acpi_ut_delete_internal_object_list(info->parameters);
456	}
457
458	ACPI_FREE(info);
459	return_ACPI_STATUS(status);
460}
461
462ACPI_EXPORT_SYMBOL(acpi_evaluate_object)
463
464/*******************************************************************************
465 *
466 * FUNCTION:    acpi_ns_resolve_references
467 *
468 * PARAMETERS:  info                    - Evaluation info block
469 *
470 * RETURN:      Info->return_object is replaced with the dereferenced object
471 *
472 * DESCRIPTION: Dereference certain reference objects. Called before an
473 *              internal return object is converted to an external union acpi_object.
474 *
475 * Performs an automatic dereference of Index and ref_of reference objects.
476 * These reference objects are not supported by the union acpi_object, so this is a
477 * last resort effort to return something useful. Also, provides compatibility
478 * with other ACPI implementations.
479 *
480 * NOTE: does not handle references within returned package objects or nested
481 * references, but this support could be added later if found to be necessary.
482 *
483 ******************************************************************************/
484static void acpi_ns_resolve_references(struct acpi_evaluate_info *info)
485{
486	union acpi_operand_object *obj_desc = NULL;
487	struct acpi_namespace_node *node;
488
489	/* We are interested in reference objects only */
490
491	if ((info->return_object)->common.type != ACPI_TYPE_LOCAL_REFERENCE) {
492		return;
493	}
494
495	/*
496	 * Two types of references are supported - those created by Index and
497	 * ref_of operators. A name reference (AML_NAMEPATH_OP) can be converted
498	 * to an union acpi_object, so it is not dereferenced here. A ddb_handle
499	 * (AML_LOAD_OP) cannot be dereferenced, nor can it be converted to
500	 * an union acpi_object.
501	 */
502	switch (info->return_object->reference.class) {
503	case ACPI_REFCLASS_INDEX:
504
505		obj_desc = *(info->return_object->reference.where);
506		break;
507
508	case ACPI_REFCLASS_REFOF:
509
510		node = info->return_object->reference.object;
511		if (node) {
512			obj_desc = node->object;
513		}
514		break;
515
516	default:
517
518		return;
519	}
520
521	/* Replace the existing reference object */
522
523	if (obj_desc) {
524		acpi_ut_add_reference(obj_desc);
525		acpi_ut_remove_reference(info->return_object);
526		info->return_object = obj_desc;
527	}
528
529	return;
530}
531
532/*******************************************************************************
533 *
534 * FUNCTION:    acpi_walk_namespace
535 *
536 * PARAMETERS:  type                - acpi_object_type to search for
537 *              start_object        - Handle in namespace where search begins
538 *              max_depth           - Depth to which search is to reach
539 *              descending_callback - Called during tree descent
540 *                                    when an object of "Type" is found
541 *              ascending_callback  - Called during tree ascent
542 *                                    when an object of "Type" is found
543 *              context             - Passed to user function(s) above
544 *              return_value        - Location where return value of
545 *                                    user_function is put if terminated early
546 *
547 * RETURNS      Return value from the user_function if terminated early.
548 *              Otherwise, returns NULL.
549 *
550 * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
551 *              starting (and ending) at the object specified by start_handle.
552 *              The callback function is called whenever an object that matches
553 *              the type parameter is found. If the callback function returns
554 *              a non-zero value, the search is terminated immediately and this
555 *              value is returned to the caller.
556 *
557 *              The point of this procedure is to provide a generic namespace
558 *              walk routine that can be called from multiple places to
559 *              provide multiple services; the callback function(s) can be
560 *              tailored to each task, whether it is a print function,
561 *              a compare function, etc.
562 *
563 ******************************************************************************/
564
565acpi_status
566acpi_walk_namespace(acpi_object_type type,
567		    acpi_handle start_object,
568		    u32 max_depth,
569		    acpi_walk_callback descending_callback,
570		    acpi_walk_callback ascending_callback,
571		    void *context, void **return_value)
572{
573	acpi_status status;
574
575	ACPI_FUNCTION_TRACE(acpi_walk_namespace);
576
577	/* Parameter validation */
578
579	if ((type > ACPI_TYPE_LOCAL_MAX) ||
580	    (!max_depth) || (!descending_callback && !ascending_callback)) {
581		return_ACPI_STATUS(AE_BAD_PARAMETER);
582	}
583
584	/*
585	 * Need to acquire the namespace reader lock to prevent interference
586	 * with any concurrent table unloads (which causes the deletion of
587	 * namespace objects). We cannot allow the deletion of a namespace node
588	 * while the user function is using it. The exception to this are the
589	 * nodes created and deleted during control method execution -- these
590	 * nodes are marked as temporary nodes and are ignored by the namespace
591	 * walk. Thus, control methods can be executed while holding the
592	 * namespace deletion lock (and the user function can execute control
593	 * methods.)
594	 */
595	status = acpi_ut_acquire_read_lock(&acpi_gbl_namespace_rw_lock);
596	if (ACPI_FAILURE(status)) {
597		return_ACPI_STATUS(status);
598	}
599
600	/*
601	 * Lock the namespace around the walk. The namespace will be
602	 * unlocked/locked around each call to the user function - since the user
603	 * function must be allowed to make ACPICA calls itself (for example, it
604	 * will typically execute control methods during device enumeration.)
605	 */
606	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
607	if (ACPI_FAILURE(status)) {
608		goto unlock_and_exit;
609	}
610
611	/* Now we can validate the starting node */
612
613	if (!acpi_ns_validate_handle(start_object)) {
614		status = AE_BAD_PARAMETER;
615		goto unlock_and_exit2;
616	}
617
618	status = acpi_ns_walk_namespace(type, start_object, max_depth,
619					ACPI_NS_WALK_UNLOCK,
620					descending_callback, ascending_callback,
621					context, return_value);
622
623unlock_and_exit2:
624	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
625
626unlock_and_exit:
627	(void)acpi_ut_release_read_lock(&acpi_gbl_namespace_rw_lock);
628	return_ACPI_STATUS(status);
629}
630
631ACPI_EXPORT_SYMBOL(acpi_walk_namespace)
632
633/*******************************************************************************
634 *
635 * FUNCTION:    acpi_ns_get_device_callback
636 *
637 * PARAMETERS:  Callback from acpi_get_device
638 *
639 * RETURN:      Status
640 *
641 * DESCRIPTION: Takes callbacks from walk_namespace and filters out all non-
642 *              present devices, or if they specified a HID, it filters based
643 *              on that.
644 *
645 ******************************************************************************/
646static acpi_status
647acpi_ns_get_device_callback(acpi_handle obj_handle,
648			    u32 nesting_level,
649			    void *context, void **return_value)
650{
651	struct acpi_get_devices_info *info = context;
652	acpi_status status;
653	struct acpi_namespace_node *node;
654	u32 flags;
655	struct acpi_pnp_device_id *hid;
656	struct acpi_pnp_device_id_list *cid;
657	u32 i;
658	u8 found;
659	int no_match;
660
661	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
662	if (ACPI_FAILURE(status)) {
663		return (status);
664	}
665
666	node = acpi_ns_validate_handle(obj_handle);
667	status = acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
668	if (ACPI_FAILURE(status)) {
669		return (status);
670	}
671
672	if (!node) {
673		return (AE_BAD_PARAMETER);
674	}
675
676	/*
677	 * First, filter based on the device HID and CID.
678	 *
679	 * 01/2010: For this case where a specific HID is requested, we don't
680	 * want to run _STA until we have an actual HID match. Thus, we will
681	 * not unnecessarily execute _STA on devices for which the caller
682	 * doesn't care about. Previously, _STA was executed unconditionally
683	 * on all devices found here.
684	 *
685	 * A side-effect of this change is that now we will continue to search
686	 * for a matching HID even under device trees where the parent device
687	 * would have returned a _STA that indicates it is not present or
688	 * not functioning (thus aborting the search on that branch).
689	 */
690	if (info->hid != NULL) {
691		status = acpi_ut_execute_HID(node, &hid);
692		if (status == AE_NOT_FOUND) {
693			return (AE_OK);
694		} else if (ACPI_FAILURE(status)) {
695			return (AE_CTRL_DEPTH);
696		}
697
698		no_match = strcmp(hid->string, info->hid);
699		ACPI_FREE(hid);
700
701		if (no_match) {
702			/*
703			 * HID does not match, attempt match within the
704			 * list of Compatible IDs (CIDs)
705			 */
706			status = acpi_ut_execute_CID(node, &cid);
707			if (status == AE_NOT_FOUND) {
708				return (AE_OK);
709			} else if (ACPI_FAILURE(status)) {
710				return (AE_CTRL_DEPTH);
711			}
712
713			/* Walk the CID list */
714
715			found = FALSE;
716			for (i = 0; i < cid->count; i++) {
717				if (strcmp(cid->ids[i].string, info->hid) == 0) {
718
719					/* Found a matching CID */
720
721					found = TRUE;
722					break;
723				}
724			}
725
726			ACPI_FREE(cid);
727			if (!found) {
728				return (AE_OK);
729			}
730		}
731	}
732
733	/* Run _STA to determine if device is present */
734
735	status = acpi_ut_execute_STA(node, &flags);
736	if (ACPI_FAILURE(status)) {
737		return (AE_CTRL_DEPTH);
738	}
739
740	if (!(flags & ACPI_STA_DEVICE_PRESENT) &&
741	    !(flags & ACPI_STA_DEVICE_FUNCTIONING)) {
742		/*
743		 * Don't examine the children of the device only when the
744		 * device is neither present nor functional. See ACPI spec,
745		 * description of _STA for more information.
746		 */
747		return (AE_CTRL_DEPTH);
748	}
749
750	/* We have a valid device, invoke the user function */
751
752	status = info->user_function(obj_handle, nesting_level,
753				     info->context, return_value);
754	return (status);
755}
756
757/*******************************************************************************
758 *
759 * FUNCTION:    acpi_get_devices
760 *
761 * PARAMETERS:  HID                 - HID to search for. Can be NULL.
762 *              user_function       - Called when a matching object is found
763 *              context             - Passed to user function
764 *              return_value        - Location where return value of
765 *                                    user_function is put if terminated early
766 *
767 * RETURNS      Return value from the user_function if terminated early.
768 *              Otherwise, returns NULL.
769 *
770 * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
771 *              starting (and ending) at the object specified by start_handle.
772 *              The user_function is called whenever an object of type
773 *              Device is found. If the user function returns
774 *              a non-zero value, the search is terminated immediately and this
775 *              value is returned to the caller.
776 *
777 *              This is a wrapper for walk_namespace, but the callback performs
778 *              additional filtering. Please see acpi_ns_get_device_callback.
779 *
780 ******************************************************************************/
781
782acpi_status
783acpi_get_devices(const char *HID,
784		 acpi_walk_callback user_function,
785		 void *context, void **return_value)
786{
787	acpi_status status;
788	struct acpi_get_devices_info info;
789
790	ACPI_FUNCTION_TRACE(acpi_get_devices);
791
792	/* Parameter validation */
793
794	if (!user_function) {
795		return_ACPI_STATUS(AE_BAD_PARAMETER);
796	}
797
798	/*
799	 * We're going to call their callback from OUR callback, so we need
800	 * to know what it is, and their context parameter.
801	 */
802	info.hid = HID;
803	info.context = context;
804	info.user_function = user_function;
805
806	/*
807	 * Lock the namespace around the walk.
808	 * The namespace will be unlocked/locked around each call
809	 * to the user function - since this function
810	 * must be allowed to make Acpi calls itself.
811	 */
812	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
813	if (ACPI_FAILURE(status)) {
814		return_ACPI_STATUS(status);
815	}
816
817	status = acpi_ns_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
818					ACPI_UINT32_MAX, ACPI_NS_WALK_UNLOCK,
819					acpi_ns_get_device_callback, NULL,
820					&info, return_value);
821
822	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
823	return_ACPI_STATUS(status);
824}
825
826ACPI_EXPORT_SYMBOL(acpi_get_devices)
827
828/*******************************************************************************
829 *
830 * FUNCTION:    acpi_attach_data
831 *
832 * PARAMETERS:  obj_handle          - Namespace node
833 *              handler             - Handler for this attachment
834 *              data                - Pointer to data to be attached
835 *
836 * RETURN:      Status
837 *
838 * DESCRIPTION: Attach arbitrary data and handler to a namespace node.
839 *
840 ******************************************************************************/
841acpi_status
842acpi_attach_data(acpi_handle obj_handle,
843		 acpi_object_handler handler, void *data)
844{
845	struct acpi_namespace_node *node;
846	acpi_status status;
847
848	/* Parameter validation */
849
850	if (!obj_handle || !handler || !data) {
851		return (AE_BAD_PARAMETER);
852	}
853
854	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
855	if (ACPI_FAILURE(status)) {
856		return (status);
857	}
858
859	/* Convert and validate the handle */
860
861	node = acpi_ns_validate_handle(obj_handle);
862	if (!node) {
863		status = AE_BAD_PARAMETER;
864		goto unlock_and_exit;
865	}
866
867	status = acpi_ns_attach_data(node, handler, data);
868
869unlock_and_exit:
870	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
871	return (status);
872}
873
874ACPI_EXPORT_SYMBOL(acpi_attach_data)
875
876/*******************************************************************************
877 *
878 * FUNCTION:    acpi_detach_data
879 *
880 * PARAMETERS:  obj_handle          - Namespace node handle
881 *              handler             - Handler used in call to acpi_attach_data
882 *
883 * RETURN:      Status
884 *
885 * DESCRIPTION: Remove data that was previously attached to a node.
886 *
887 ******************************************************************************/
888acpi_status
889acpi_detach_data(acpi_handle obj_handle, acpi_object_handler handler)
890{
891	struct acpi_namespace_node *node;
892	acpi_status status;
893
894	/* Parameter validation */
895
896	if (!obj_handle || !handler) {
897		return (AE_BAD_PARAMETER);
898	}
899
900	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
901	if (ACPI_FAILURE(status)) {
902		return (status);
903	}
904
905	/* Convert and validate the handle */
906
907	node = acpi_ns_validate_handle(obj_handle);
908	if (!node) {
909		status = AE_BAD_PARAMETER;
910		goto unlock_and_exit;
911	}
912
913	status = acpi_ns_detach_data(node, handler);
914
915unlock_and_exit:
916	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
917	return (status);
918}
919
920ACPI_EXPORT_SYMBOL(acpi_detach_data)
921
922/*******************************************************************************
923 *
924 * FUNCTION:    acpi_get_data_full
925 *
926 * PARAMETERS:  obj_handle          - Namespace node
927 *              handler             - Handler used in call to attach_data
928 *              data                - Where the data is returned
929 *              callback            - function to execute before returning
930 *
931 * RETURN:      Status
932 *
933 * DESCRIPTION: Retrieve data that was previously attached to a namespace node
934 *              and execute a callback before returning.
935 *
936 ******************************************************************************/
937acpi_status
938acpi_get_data_full(acpi_handle obj_handle, acpi_object_handler handler,
939		   void **data, void (*callback)(void *))
940{
941	struct acpi_namespace_node *node;
942	acpi_status status;
943
944	/* Parameter validation */
945
946	if (!obj_handle || !handler || !data) {
947		return (AE_BAD_PARAMETER);
948	}
949
950	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
951	if (ACPI_FAILURE(status)) {
952		return (status);
953	}
954
955	/* Convert and validate the handle */
956
957	node = acpi_ns_validate_handle(obj_handle);
958	if (!node) {
959		status = AE_BAD_PARAMETER;
960		goto unlock_and_exit;
961	}
962
963	status = acpi_ns_get_attached_data(node, handler, data);
964	if (ACPI_SUCCESS(status) && callback) {
965		callback(*data);
966	}
967
968unlock_and_exit:
969	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
970	return (status);
971}
972
973ACPI_EXPORT_SYMBOL(acpi_get_data_full)
974
975/*******************************************************************************
976 *
977 * FUNCTION:    acpi_get_data
978 *
979 * PARAMETERS:  obj_handle          - Namespace node
980 *              handler             - Handler used in call to attach_data
981 *              data                - Where the data is returned
982 *
983 * RETURN:      Status
984 *
985 * DESCRIPTION: Retrieve data that was previously attached to a namespace node.
986 *
987 ******************************************************************************/
988acpi_status
989acpi_get_data(acpi_handle obj_handle, acpi_object_handler handler, void **data)
990{
991	return acpi_get_data_full(obj_handle, handler, data, NULL);
992}
993
994ACPI_EXPORT_SYMBOL(acpi_get_data)