Merge branch 'alarm' into release
[linux-2.6] / drivers / acpi / acpica / nsobject.c
1 /*******************************************************************************
2  *
3  * Module Name: nsobject - Utilities for objects attached to namespace
4  *                         table entries
5  *
6  ******************************************************************************/
7
8 /*
9  * Copyright (C) 2000 - 2008, 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
49 #define _COMPONENT          ACPI_NAMESPACE
50 ACPI_MODULE_NAME("nsobject")
51
52 /*******************************************************************************
53  *
54  * FUNCTION:    acpi_ns_attach_object
55  *
56  * PARAMETERS:  Node                - Parent Node
57  *              Object              - Object to be attached
58  *              Type                - Type of object, or ACPI_TYPE_ANY if not
59  *                                    known
60  *
61  * RETURN:      Status
62  *
63  * DESCRIPTION: Record the given object as the value associated with the
64  *              name whose acpi_handle is passed.  If Object is NULL
65  *              and Type is ACPI_TYPE_ANY, set the name as having no value.
66  *              Note: Future may require that the Node->Flags field be passed
67  *              as a parameter.
68  *
69  * MUTEX:       Assumes namespace is locked
70  *
71  ******************************************************************************/
72 acpi_status
73 acpi_ns_attach_object(struct acpi_namespace_node *node,
74                       union acpi_operand_object *object, acpi_object_type type)
75 {
76         union acpi_operand_object *obj_desc;
77         union acpi_operand_object *last_obj_desc;
78         acpi_object_type object_type = ACPI_TYPE_ANY;
79
80         ACPI_FUNCTION_TRACE(ns_attach_object);
81
82         /*
83          * Parameter validation
84          */
85         if (!node) {
86
87                 /* Invalid handle */
88
89                 ACPI_ERROR((AE_INFO, "Null NamedObj handle"));
90                 return_ACPI_STATUS(AE_BAD_PARAMETER);
91         }
92
93         if (!object && (ACPI_TYPE_ANY != type)) {
94
95                 /* Null object */
96
97                 ACPI_ERROR((AE_INFO,
98                             "Null object, but type not ACPI_TYPE_ANY"));
99                 return_ACPI_STATUS(AE_BAD_PARAMETER);
100         }
101
102         if (ACPI_GET_DESCRIPTOR_TYPE(node) != ACPI_DESC_TYPE_NAMED) {
103
104                 /* Not a name handle */
105
106                 ACPI_ERROR((AE_INFO, "Invalid handle %p [%s]",
107                             node, acpi_ut_get_descriptor_name(node)));
108                 return_ACPI_STATUS(AE_BAD_PARAMETER);
109         }
110
111         /* Check if this object is already attached */
112
113         if (node->object == object) {
114                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
115                                   "Obj %p already installed in NameObj %p\n",
116                                   object, node));
117
118                 return_ACPI_STATUS(AE_OK);
119         }
120
121         /* If null object, we will just install it */
122
123         if (!object) {
124                 obj_desc = NULL;
125                 object_type = ACPI_TYPE_ANY;
126         }
127
128         /*
129          * If the source object is a namespace Node with an attached object,
130          * we will use that (attached) object
131          */
132         else if ((ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_NAMED) &&
133                  ((struct acpi_namespace_node *)object)->object) {
134                 /*
135                  * Value passed is a name handle and that name has a
136                  * non-null value.  Use that name's value and type.
137                  */
138                 obj_desc = ((struct acpi_namespace_node *)object)->object;
139                 object_type = ((struct acpi_namespace_node *)object)->type;
140         }
141
142         /*
143          * Otherwise, we will use the parameter object, but we must type
144          * it first
145          */
146         else {
147                 obj_desc = (union acpi_operand_object *)object;
148
149                 /* Use the given type */
150
151                 object_type = type;
152         }
153
154         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Installing %p into Node %p [%4.4s]\n",
155                           obj_desc, node, acpi_ut_get_node_name(node)));
156
157         /* Detach an existing attached object if present */
158
159         if (node->object) {
160                 acpi_ns_detach_object(node);
161         }
162
163         if (obj_desc) {
164                 /*
165                  * Must increment the new value's reference count
166                  * (if it is an internal object)
167                  */
168                 acpi_ut_add_reference(obj_desc);
169
170                 /*
171                  * Handle objects with multiple descriptors - walk
172                  * to the end of the descriptor list
173                  */
174                 last_obj_desc = obj_desc;
175                 while (last_obj_desc->common.next_object) {
176                         last_obj_desc = last_obj_desc->common.next_object;
177                 }
178
179                 /* Install the object at the front of the object list */
180
181                 last_obj_desc->common.next_object = node->object;
182         }
183
184         node->type = (u8) object_type;
185         node->object = obj_desc;
186
187         return_ACPI_STATUS(AE_OK);
188 }
189
190 /*******************************************************************************
191  *
192  * FUNCTION:    acpi_ns_detach_object
193  *
194  * PARAMETERS:  Node           - A Namespace node whose object will be detached
195  *
196  * RETURN:      None.
197  *
198  * DESCRIPTION: Detach/delete an object associated with a namespace node.
199  *              if the object is an allocated object, it is freed.
200  *              Otherwise, the field is simply cleared.
201  *
202  ******************************************************************************/
203
204 void acpi_ns_detach_object(struct acpi_namespace_node *node)
205 {
206         union acpi_operand_object *obj_desc;
207
208         ACPI_FUNCTION_TRACE(ns_detach_object);
209
210         obj_desc = node->object;
211
212         if (!obj_desc ||
213             (ACPI_GET_OBJECT_TYPE(obj_desc) == ACPI_TYPE_LOCAL_DATA)) {
214                 return_VOID;
215         }
216
217         /* Clear the entry in all cases */
218
219         node->object = NULL;
220         if (ACPI_GET_DESCRIPTOR_TYPE(obj_desc) == ACPI_DESC_TYPE_OPERAND) {
221                 node->object = obj_desc->common.next_object;
222                 if (node->object &&
223                     (ACPI_GET_OBJECT_TYPE(node->object) !=
224                      ACPI_TYPE_LOCAL_DATA)) {
225                         node->object = node->object->common.next_object;
226                 }
227         }
228
229         /* Reset the node type to untyped */
230
231         node->type = ACPI_TYPE_ANY;
232
233         ACPI_DEBUG_PRINT((ACPI_DB_NAMES, "Node %p [%4.4s] Object %p\n",
234                           node, acpi_ut_get_node_name(node), obj_desc));
235
236         /* Remove one reference on the object (and all subobjects) */
237
238         acpi_ut_remove_reference(obj_desc);
239         return_VOID;
240 }
241
242 /*******************************************************************************
243  *
244  * FUNCTION:    acpi_ns_get_attached_object
245  *
246  * PARAMETERS:  Node             - Namespace node
247  *
248  * RETURN:      Current value of the object field from the Node whose
249  *              handle is passed
250  *
251  * DESCRIPTION: Obtain the object attached to a namespace node.
252  *
253  ******************************************************************************/
254
255 union acpi_operand_object *acpi_ns_get_attached_object(struct
256                                                        acpi_namespace_node
257                                                        *node)
258 {
259         ACPI_FUNCTION_TRACE_PTR(ns_get_attached_object, node);
260
261         if (!node) {
262                 ACPI_WARNING((AE_INFO, "Null Node ptr"));
263                 return_PTR(NULL);
264         }
265
266         if (!node->object ||
267             ((ACPI_GET_DESCRIPTOR_TYPE(node->object) != ACPI_DESC_TYPE_OPERAND)
268              && (ACPI_GET_DESCRIPTOR_TYPE(node->object) !=
269                  ACPI_DESC_TYPE_NAMED))
270             || (ACPI_GET_OBJECT_TYPE(node->object) == ACPI_TYPE_LOCAL_DATA)) {
271                 return_PTR(NULL);
272         }
273
274         return_PTR(node->object);
275 }
276
277 /*******************************************************************************
278  *
279  * FUNCTION:    acpi_ns_get_secondary_object
280  *
281  * PARAMETERS:  Node             - Namespace node
282  *
283  * RETURN:      Current value of the object field from the Node whose
284  *              handle is passed.
285  *
286  * DESCRIPTION: Obtain a secondary object associated with a namespace node.
287  *
288  ******************************************************************************/
289
290 union acpi_operand_object *acpi_ns_get_secondary_object(union
291                                                         acpi_operand_object
292                                                         *obj_desc)
293 {
294         ACPI_FUNCTION_TRACE_PTR(ns_get_secondary_object, obj_desc);
295
296         if ((!obj_desc) ||
297             (ACPI_GET_OBJECT_TYPE(obj_desc) == ACPI_TYPE_LOCAL_DATA) ||
298             (!obj_desc->common.next_object) ||
299             (ACPI_GET_OBJECT_TYPE(obj_desc->common.next_object) ==
300              ACPI_TYPE_LOCAL_DATA)) {
301                 return_PTR(NULL);
302         }
303
304         return_PTR(obj_desc->common.next_object);
305 }
306
307 /*******************************************************************************
308  *
309  * FUNCTION:    acpi_ns_attach_data
310  *
311  * PARAMETERS:  Node            - Namespace node
312  *              Handler         - Handler to be associated with the data
313  *              Data            - Data to be attached
314  *
315  * RETURN:      Status
316  *
317  * DESCRIPTION: Low-level attach data.  Create and attach a Data object.
318  *
319  ******************************************************************************/
320
321 acpi_status
322 acpi_ns_attach_data(struct acpi_namespace_node *node,
323                     acpi_object_handler handler, void *data)
324 {
325         union acpi_operand_object *prev_obj_desc;
326         union acpi_operand_object *obj_desc;
327         union acpi_operand_object *data_desc;
328
329         /* We only allow one attachment per handler */
330
331         prev_obj_desc = NULL;
332         obj_desc = node->object;
333         while (obj_desc) {
334                 if ((ACPI_GET_OBJECT_TYPE(obj_desc) == ACPI_TYPE_LOCAL_DATA) &&
335                     (obj_desc->data.handler == handler)) {
336                         return (AE_ALREADY_EXISTS);
337                 }
338
339                 prev_obj_desc = obj_desc;
340                 obj_desc = obj_desc->common.next_object;
341         }
342
343         /* Create an internal object for the data */
344
345         data_desc = acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_DATA);
346         if (!data_desc) {
347                 return (AE_NO_MEMORY);
348         }
349
350         data_desc->data.handler = handler;
351         data_desc->data.pointer = data;
352
353         /* Install the data object */
354
355         if (prev_obj_desc) {
356                 prev_obj_desc->common.next_object = data_desc;
357         } else {
358                 node->object = data_desc;
359         }
360
361         return (AE_OK);
362 }
363
364 /*******************************************************************************
365  *
366  * FUNCTION:    acpi_ns_detach_data
367  *
368  * PARAMETERS:  Node            - Namespace node
369  *              Handler         - Handler associated with the data
370  *
371  * RETURN:      Status
372  *
373  * DESCRIPTION: Low-level detach data.  Delete the data node, but the caller
374  *              is responsible for the actual data.
375  *
376  ******************************************************************************/
377
378 acpi_status
379 acpi_ns_detach_data(struct acpi_namespace_node * node,
380                     acpi_object_handler handler)
381 {
382         union acpi_operand_object *obj_desc;
383         union acpi_operand_object *prev_obj_desc;
384
385         prev_obj_desc = NULL;
386         obj_desc = node->object;
387         while (obj_desc) {
388                 if ((ACPI_GET_OBJECT_TYPE(obj_desc) == ACPI_TYPE_LOCAL_DATA) &&
389                     (obj_desc->data.handler == handler)) {
390                         if (prev_obj_desc) {
391                                 prev_obj_desc->common.next_object =
392                                     obj_desc->common.next_object;
393                         } else {
394                                 node->object = obj_desc->common.next_object;
395                         }
396
397                         acpi_ut_remove_reference(obj_desc);
398                         return (AE_OK);
399                 }
400
401                 prev_obj_desc = obj_desc;
402                 obj_desc = obj_desc->common.next_object;
403         }
404
405         return (AE_NOT_FOUND);
406 }
407
408 /*******************************************************************************
409  *
410  * FUNCTION:    acpi_ns_get_attached_data
411  *
412  * PARAMETERS:  Node            - Namespace node
413  *              Handler         - Handler associated with the data
414  *              Data            - Where the data is returned
415  *
416  * RETURN:      Status
417  *
418  * DESCRIPTION: Low level interface to obtain data previously associated with
419  *              a namespace node.
420  *
421  ******************************************************************************/
422
423 acpi_status
424 acpi_ns_get_attached_data(struct acpi_namespace_node * node,
425                           acpi_object_handler handler, void **data)
426 {
427         union acpi_operand_object *obj_desc;
428
429         obj_desc = node->object;
430         while (obj_desc) {
431                 if ((ACPI_GET_OBJECT_TYPE(obj_desc) == ACPI_TYPE_LOCAL_DATA) &&
432                     (obj_desc->data.handler == handler)) {
433                         *data = obj_desc->data.pointer;
434                         return (AE_OK);
435                 }
436
437                 obj_desc = obj_desc->common.next_object;
438         }
439
440         return (AE_NOT_FOUND);
441 }