Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/kaber/nf-2.6
[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 || (obj_desc->common.type == ACPI_TYPE_LOCAL_DATA)) {
213                 return_VOID;
214         }
215
216         /* Clear the entry in all cases */
217
218         node->object = NULL;
219         if (ACPI_GET_DESCRIPTOR_TYPE(obj_desc) == ACPI_DESC_TYPE_OPERAND) {
220                 node->object = obj_desc->common.next_object;
221                 if (node->object &&
222                     ((node->object)->common.type != ACPI_TYPE_LOCAL_DATA)) {
223                         node->object = node->object->common.next_object;
224                 }
225         }
226
227         /* Reset the node type to untyped */
228
229         node->type = ACPI_TYPE_ANY;
230
231         ACPI_DEBUG_PRINT((ACPI_DB_NAMES, "Node %p [%4.4s] Object %p\n",
232                           node, acpi_ut_get_node_name(node), obj_desc));
233
234         /* Remove one reference on the object (and all subobjects) */
235
236         acpi_ut_remove_reference(obj_desc);
237         return_VOID;
238 }
239
240 /*******************************************************************************
241  *
242  * FUNCTION:    acpi_ns_get_attached_object
243  *
244  * PARAMETERS:  Node             - Namespace node
245  *
246  * RETURN:      Current value of the object field from the Node whose
247  *              handle is passed
248  *
249  * DESCRIPTION: Obtain the object attached to a namespace node.
250  *
251  ******************************************************************************/
252
253 union acpi_operand_object *acpi_ns_get_attached_object(struct
254                                                        acpi_namespace_node
255                                                        *node)
256 {
257         ACPI_FUNCTION_TRACE_PTR(ns_get_attached_object, node);
258
259         if (!node) {
260                 ACPI_WARNING((AE_INFO, "Null Node ptr"));
261                 return_PTR(NULL);
262         }
263
264         if (!node->object ||
265             ((ACPI_GET_DESCRIPTOR_TYPE(node->object) != ACPI_DESC_TYPE_OPERAND)
266              && (ACPI_GET_DESCRIPTOR_TYPE(node->object) !=
267                  ACPI_DESC_TYPE_NAMED))
268             || ((node->object)->common.type == ACPI_TYPE_LOCAL_DATA)) {
269                 return_PTR(NULL);
270         }
271
272         return_PTR(node->object);
273 }
274
275 /*******************************************************************************
276  *
277  * FUNCTION:    acpi_ns_get_secondary_object
278  *
279  * PARAMETERS:  Node             - Namespace node
280  *
281  * RETURN:      Current value of the object field from the Node whose
282  *              handle is passed.
283  *
284  * DESCRIPTION: Obtain a secondary object associated with a namespace node.
285  *
286  ******************************************************************************/
287
288 union acpi_operand_object *acpi_ns_get_secondary_object(union
289                                                         acpi_operand_object
290                                                         *obj_desc)
291 {
292         ACPI_FUNCTION_TRACE_PTR(ns_get_secondary_object, obj_desc);
293
294         if ((!obj_desc) ||
295             (obj_desc->common.type == ACPI_TYPE_LOCAL_DATA) ||
296             (!obj_desc->common.next_object) ||
297             ((obj_desc->common.next_object)->common.type ==
298              ACPI_TYPE_LOCAL_DATA)) {
299                 return_PTR(NULL);
300         }
301
302         return_PTR(obj_desc->common.next_object);
303 }
304
305 /*******************************************************************************
306  *
307  * FUNCTION:    acpi_ns_attach_data
308  *
309  * PARAMETERS:  Node            - Namespace node
310  *              Handler         - Handler to be associated with the data
311  *              Data            - Data to be attached
312  *
313  * RETURN:      Status
314  *
315  * DESCRIPTION: Low-level attach data.  Create and attach a Data object.
316  *
317  ******************************************************************************/
318
319 acpi_status
320 acpi_ns_attach_data(struct acpi_namespace_node *node,
321                     acpi_object_handler handler, void *data)
322 {
323         union acpi_operand_object *prev_obj_desc;
324         union acpi_operand_object *obj_desc;
325         union acpi_operand_object *data_desc;
326
327         /* We only allow one attachment per handler */
328
329         prev_obj_desc = NULL;
330         obj_desc = node->object;
331         while (obj_desc) {
332                 if ((obj_desc->common.type == ACPI_TYPE_LOCAL_DATA) &&
333                     (obj_desc->data.handler == handler)) {
334                         return (AE_ALREADY_EXISTS);
335                 }
336
337                 prev_obj_desc = obj_desc;
338                 obj_desc = obj_desc->common.next_object;
339         }
340
341         /* Create an internal object for the data */
342
343         data_desc = acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_DATA);
344         if (!data_desc) {
345                 return (AE_NO_MEMORY);
346         }
347
348         data_desc->data.handler = handler;
349         data_desc->data.pointer = data;
350
351         /* Install the data object */
352
353         if (prev_obj_desc) {
354                 prev_obj_desc->common.next_object = data_desc;
355         } else {
356                 node->object = data_desc;
357         }
358
359         return (AE_OK);
360 }
361
362 /*******************************************************************************
363  *
364  * FUNCTION:    acpi_ns_detach_data
365  *
366  * PARAMETERS:  Node            - Namespace node
367  *              Handler         - Handler associated with the data
368  *
369  * RETURN:      Status
370  *
371  * DESCRIPTION: Low-level detach data.  Delete the data node, but the caller
372  *              is responsible for the actual data.
373  *
374  ******************************************************************************/
375
376 acpi_status
377 acpi_ns_detach_data(struct acpi_namespace_node * node,
378                     acpi_object_handler handler)
379 {
380         union acpi_operand_object *obj_desc;
381         union acpi_operand_object *prev_obj_desc;
382
383         prev_obj_desc = NULL;
384         obj_desc = node->object;
385         while (obj_desc) {
386                 if ((obj_desc->common.type == ACPI_TYPE_LOCAL_DATA) &&
387                     (obj_desc->data.handler == handler)) {
388                         if (prev_obj_desc) {
389                                 prev_obj_desc->common.next_object =
390                                     obj_desc->common.next_object;
391                         } else {
392                                 node->object = obj_desc->common.next_object;
393                         }
394
395                         acpi_ut_remove_reference(obj_desc);
396                         return (AE_OK);
397                 }
398
399                 prev_obj_desc = obj_desc;
400                 obj_desc = obj_desc->common.next_object;
401         }
402
403         return (AE_NOT_FOUND);
404 }
405
406 /*******************************************************************************
407  *
408  * FUNCTION:    acpi_ns_get_attached_data
409  *
410  * PARAMETERS:  Node            - Namespace node
411  *              Handler         - Handler associated with the data
412  *              Data            - Where the data is returned
413  *
414  * RETURN:      Status
415  *
416  * DESCRIPTION: Low level interface to obtain data previously associated with
417  *              a namespace node.
418  *
419  ******************************************************************************/
420
421 acpi_status
422 acpi_ns_get_attached_data(struct acpi_namespace_node * node,
423                           acpi_object_handler handler, void **data)
424 {
425         union acpi_operand_object *obj_desc;
426
427         obj_desc = node->object;
428         while (obj_desc) {
429                 if ((obj_desc->common.type == ACPI_TYPE_LOCAL_DATA) &&
430                     (obj_desc->data.handler == handler)) {
431                         *data = obj_desc->data.pointer;
432                         return (AE_OK);
433                 }
434
435                 obj_desc = obj_desc->common.next_object;
436         }
437
438         return (AE_NOT_FOUND);
439 }