xref: /linux/drivers/acpi/acpica/nsxfobj.c (revision b6ebbac51bedf9e98e837688bc838f400196da5e)
1 /*******************************************************************************
2  *
3  * Module Name: nsxfobj - Public interfaces to the ACPI subsystem
4  *                         ACPI Object oriented 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 
51 #define _COMPONENT          ACPI_NAMESPACE
52 ACPI_MODULE_NAME("nsxfobj")
53 
54 /*******************************************************************************
55  *
56  * FUNCTION:    acpi_get_type
57  *
58  * PARAMETERS:  handle          - Handle of object whose type is desired
59  *              ret_type        - Where the type will be placed
60  *
61  * RETURN:      Status
62  *
63  * DESCRIPTION: This routine returns the type associatd with a particular handle
64  *
65  ******************************************************************************/
66 acpi_status acpi_get_type(acpi_handle handle, acpi_object_type *ret_type)
67 {
68 	struct acpi_namespace_node *node;
69 	acpi_status status;
70 
71 	/* Parameter Validation */
72 
73 	if (!ret_type) {
74 		return (AE_BAD_PARAMETER);
75 	}
76 
77 	/* Special case for the predefined Root Node (return type ANY) */
78 
79 	if (handle == ACPI_ROOT_OBJECT) {
80 		*ret_type = ACPI_TYPE_ANY;
81 		return (AE_OK);
82 	}
83 
84 	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
85 	if (ACPI_FAILURE(status)) {
86 		return (status);
87 	}
88 
89 	/* Convert and validate the handle */
90 
91 	node = acpi_ns_validate_handle(handle);
92 	if (!node) {
93 		(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
94 		return (AE_BAD_PARAMETER);
95 	}
96 
97 	*ret_type = node->type;
98 
99 	status = acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
100 	return (status);
101 }
102 
103 ACPI_EXPORT_SYMBOL(acpi_get_type)
104 
105 /*******************************************************************************
106  *
107  * FUNCTION:    acpi_get_parent
108  *
109  * PARAMETERS:  handle          - Handle of object whose parent is desired
110  *              ret_handle      - Where the parent handle will be placed
111  *
112  * RETURN:      Status
113  *
114  * DESCRIPTION: Returns a handle to the parent of the object represented by
115  *              Handle.
116  *
117  ******************************************************************************/
118 acpi_status acpi_get_parent(acpi_handle handle, acpi_handle *ret_handle)
119 {
120 	struct acpi_namespace_node *node;
121 	struct acpi_namespace_node *parent_node;
122 	acpi_status status;
123 
124 	if (!ret_handle) {
125 		return (AE_BAD_PARAMETER);
126 	}
127 
128 	/* Special case for the predefined Root Node (no parent) */
129 
130 	if (handle == ACPI_ROOT_OBJECT) {
131 		return (AE_NULL_ENTRY);
132 	}
133 
134 	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
135 	if (ACPI_FAILURE(status)) {
136 		return (status);
137 	}
138 
139 	/* Convert and validate the handle */
140 
141 	node = acpi_ns_validate_handle(handle);
142 	if (!node) {
143 		status = AE_BAD_PARAMETER;
144 		goto unlock_and_exit;
145 	}
146 
147 	/* Get the parent entry */
148 
149 	parent_node = node->parent;
150 	*ret_handle = ACPI_CAST_PTR(acpi_handle, parent_node);
151 
152 	/* Return exception if parent is null */
153 
154 	if (!parent_node) {
155 		status = AE_NULL_ENTRY;
156 	}
157 
158 unlock_and_exit:
159 
160 	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
161 	return (status);
162 }
163 
164 ACPI_EXPORT_SYMBOL(acpi_get_parent)
165 
166 /*******************************************************************************
167  *
168  * FUNCTION:    acpi_get_next_object
169  *
170  * PARAMETERS:  type            - Type of object to be searched for
171  *              parent          - Parent object whose children we are getting
172  *              last_child      - Previous child that was found.
173  *                                The NEXT child will be returned
174  *              ret_handle      - Where handle to the next object is placed
175  *
176  * RETURN:      Status
177  *
178  * DESCRIPTION: Return the next peer object within the namespace. If Handle is
179  *              valid, Scope is ignored. Otherwise, the first object within
180  *              Scope is returned.
181  *
182  ******************************************************************************/
183 acpi_status
184 acpi_get_next_object(acpi_object_type type,
185 		     acpi_handle parent,
186 		     acpi_handle child, acpi_handle *ret_handle)
187 {
188 	acpi_status status;
189 	struct acpi_namespace_node *node;
190 	struct acpi_namespace_node *parent_node = NULL;
191 	struct acpi_namespace_node *child_node = NULL;
192 
193 	/* Parameter validation */
194 
195 	if (type > ACPI_TYPE_EXTERNAL_MAX) {
196 		return (AE_BAD_PARAMETER);
197 	}
198 
199 	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
200 	if (ACPI_FAILURE(status)) {
201 		return (status);
202 	}
203 
204 	/* If null handle, use the parent */
205 
206 	if (!child) {
207 
208 		/* Start search at the beginning of the specified scope */
209 
210 		parent_node = acpi_ns_validate_handle(parent);
211 		if (!parent_node) {
212 			status = AE_BAD_PARAMETER;
213 			goto unlock_and_exit;
214 		}
215 	} else {
216 		/* Non-null handle, ignore the parent */
217 		/* Convert and validate the handle */
218 
219 		child_node = acpi_ns_validate_handle(child);
220 		if (!child_node) {
221 			status = AE_BAD_PARAMETER;
222 			goto unlock_and_exit;
223 		}
224 	}
225 
226 	/* Internal function does the real work */
227 
228 	node = acpi_ns_get_next_node_typed(type, parent_node, child_node);
229 	if (!node) {
230 		status = AE_NOT_FOUND;
231 		goto unlock_and_exit;
232 	}
233 
234 	if (ret_handle) {
235 		*ret_handle = ACPI_CAST_PTR(acpi_handle, node);
236 	}
237 
238 unlock_and_exit:
239 
240 	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
241 	return (status);
242 }
243 
244 ACPI_EXPORT_SYMBOL(acpi_get_next_object)
245