Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
[linux-2.6] / drivers / acpi / namespace / 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 <acpi/acnamesp.h>
47
48 #define _COMPONENT          ACPI_NAMESPACE
49 ACPI_MODULE_NAME("nsobject")
50
51 /*******************************************************************************
52  *
53  * FUNCTION:    acpi_ns_attach_object
54  *
55  * PARAMETERS:  Node                - Parent Node
56  *              Object              - Object to be attached
57  *              Type                - Type of object, or ACPI_TYPE_ANY if not
58  *                                    known
59  *
60  * RETURN:      Status
61  *
62  * DESCRIPTION: Record the given object as the value associated with the
63  *              name whose acpi_handle is passed.  If Object is NULL
64  *              and Type is ACPI_TYPE_ANY, set the name as having no value.
65  *              Note: Future may require that the Node->Flags field be passed
66  *              as a parameter.
67  *
68  * MUTEX:       Assumes namespace is locked
69  *
70  ******************************************************************************/
71 acpi_status
72 acpi_ns_attach_object(struct acpi_namespace_node *node,
73                       union acpi_operand_object *object, acpi_object_type type)
74 {
75         union acpi_operand_object *obj_desc;
76         union acpi_operand_object *last_obj_desc;
77         acpi_object_type object_type = ACPI_TYPE_ANY;
78
79         ACPI_FUNCTION_TRACE(ns_attach_object);
80
81         /*
82          * Parameter validation
83          */
84         if (!node) {
85
86                 /* Invalid handle */
87
88                 ACPI_ERROR((AE_INFO, "Null NamedObj handle"));
89                 return_ACPI_STATUS(AE_BAD_PARAMETER);
90         }
91
92         if (!object && (ACPI_TYPE_ANY != type)) {
93
94                 /* Null object */
95
96                 ACPI_ERROR((AE_INFO,
97                             "Null object, but type not ACPI_TYPE_ANY"));
98                 return_ACPI_STATUS(AE_BAD_PARAMETER);
99         }
100
101         if (ACPI_GET_DESCRIPTOR_TYPE(node) != ACPI_DESC_TYPE_NAMED) {
102
103                 /* Not a name handle */
104
105                 ACPI_ERROR((AE_INFO, "Invalid handle %p [%s]",
106                             node, acpi_ut_get_descriptor_name(node)));
107                 return_ACPI_STATUS(AE_BAD_PARAMETER);
108         }
109
110         /* Check if this object is already attached */
111
112         if (node->object == object) {
113                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
114                                   "Obj %p already installed in NameObj %p\n",
115                                   object, node));
116
117                 return_ACPI_STATUS(AE_OK);
118         }
119
120         /* If null object, we will just install it */
121
122         if (!object) {
123                 obj_desc = NULL;
124                 object_type = ACPI_TYPE_ANY;
125         }
126
127         /*
128          * If the source object is a namespace Node with an attached object,
129          * we will use that (attached) object
130          */
131         else if ((ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_NAMED) &&
132                  ((struct acpi_namespace_node *)object)->object) {
133                 /*
134                  * Value passed is a name handle and that name has a
135                  * non-null value.  Use that name's value and type.
136                  */
137                 obj_desc = ((struct acpi_namespace_node *)object)->object;
138                 object_type = ((struct acpi_namespace_node *)object)->type;
139         }
140
141         /*
142          * Otherwise, we will use the parameter object, but we must type
143          * it first
144          */
145         else {
146                 obj_desc = (union acpi_operand_object *)object;
147
148                 /* Use the given type */
149
150                 object_type = type;
151         }
152
153         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Installing %p into Node %p [%4.4s]\n",
154                           obj_desc, node, acpi_ut_get_node_name(node)));
155
156         /* Detach an existing attached object if present */
157
158         if (node->object) {
159                 acpi_ns_detach_object(node);
160         }
161
162         if (obj_desc) {
163                 /*
164                  * Must increment the new value's reference count
165                  * (if it is an internal object)
166                  */
167                 acpi_ut_add_reference(obj_desc);
168
169                 /*
170                  * Handle objects with multiple descriptors - walk
171                  * to the end of the descriptor list
172                  */
173                 last_obj_desc = obj_desc;
174                 while (last_obj_desc->common.next_object) {
175                         last_obj_desc = last_obj_desc->common.next_object;
176                 }
177
178                 /* Install the object at the front of the object list */
179
180                 last_obj_desc->common.next_object = node->object;
181         }
182
183         node->type = (u8) object_type;
184         node->object = obj_desc;
185
186         return_ACPI_STATUS(AE_OK);
187 }
188
189 /*******************************************************************************
190  *
191  * FUNCTION:    acpi_ns_detach_object
192  *
193  * PARAMETERS:  Node           - A Namespace node whose object will be detached
194  *
195  * RETURN:      None.
196  *
197  * DESCRIPTION: Detach/delete an object associated with a namespace node.
198  *              if the object is an allocated object, it is freed.
199  *              Otherwise, the field is simply cleared.
200  *
201  ******************************************************************************/
202
203 void acpi_ns_detach_object(struct acpi_namespace_node *node)
204 {
205         union acpi_operand_object *obj_desc;
206
207         ACPI_FUNCTION_TRACE(ns_detach_object);
208
209         obj_desc = node->object;
210
211         if (!obj_desc ||
212             (ACPI_GET_OBJECT_TYPE(obj_desc) == 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                     (ACPI_GET_OBJECT_TYPE(node->object) !=
223                      ACPI_TYPE_LOCAL_DATA)) {
224                         node->object = node->object->common.next_object;
225                 }
226         }
227
228         /* Reset the node type to untyped */
229
230         node->type = ACPI_TYPE_ANY;
231
232         ACPI_DEBUG_PRINT((ACPI_DB_NAMES, "Node %p [%4.4s] Object %p\n",
233                           node, acpi_ut_get_node_name(node), obj_desc));
234
235         /* Remove one reference on the object (and all subobjects) */
236
237         acpi_ut_remove_reference(obj_desc);
238         return_VOID;
239 }
240
241 /*******************************************************************************
242  *
243  * FUNCTION:    acpi_ns_get_attached_object
244  *
245  * PARAMETERS:  Node             - Namespace node
246  *
247  * RETURN:      Current value of the object field from the Node whose
248  *              handle is passed
249  *
250  * DESCRIPTION: Obtain the object attached to a namespace node.
251  *
252  ******************************************************************************/
253
254 union acpi_operand_object *acpi_ns_get_attached_object(struct
255                                                        acpi_namespace_node
256                                                        *node)
257 {
258         ACPI_FUNCTION_TRACE_PTR(ns_get_attached_object, node);
259
260         if (!node) {
261                 ACPI_WARNING((AE_INFO, "Null Node ptr"));
262                 return_PTR(NULL);
263         }
264
265         if (!node->object ||
266             ((ACPI_GET_DESCRIPTOR_TYPE(node->object) != ACPI_DESC_TYPE_OPERAND)
267              && (ACPI_GET_DESCRIPTOR_TYPE(node->object) !=
268                  ACPI_DESC_TYPE_NAMED))
269             || (ACPI_GET_OBJECT_TYPE(node->object) == ACPI_TYPE_LOCAL_DATA)) {
270                 return_PTR(NULL);
271         }
272
273         return_PTR(node->object);
274 }
275
276 /*******************************************************************************
277  *
278  * FUNCTION:    acpi_ns_get_secondary_object
279  *
280  * PARAMETERS:  Node             - Namespace node
281  *
282  * RETURN:      Current value of the object field from the Node whose
283  *              handle is passed.
284  *
285  * DESCRIPTION: Obtain a secondary object associated with a namespace node.
286  *
287  ******************************************************************************/
288
289 union acpi_operand_object *acpi_ns_get_secondary_object(union
290                                                         acpi_operand_object
291                                                         *obj_desc)
292 {
293         ACPI_FUNCTION_TRACE_PTR(ns_get_secondary_object, obj_desc);
294
295         if ((!obj_desc) ||
296             (ACPI_GET_OBJECT_TYPE(obj_desc) == ACPI_TYPE_LOCAL_DATA) ||
297             (!obj_desc->common.next_object) ||
298             (ACPI_GET_OBJECT_TYPE(obj_desc->common.next_object) ==
299              ACPI_TYPE_LOCAL_DATA)) {
300                 return_PTR(NULL);
301         }
302
303         return_PTR(obj_desc->common.next_object);
304 }
305
306 /*******************************************************************************
307  *
308  * FUNCTION:    acpi_ns_attach_data
309  *
310  * PARAMETERS:  Node            - Namespace node
311  *              Handler         - Handler to be associated with the data
312  *              Data            - Data to be attached
313  *
314  * RETURN:      Status
315  *
316  * DESCRIPTION: Low-level attach data.  Create and attach a Data object.
317  *
318  ******************************************************************************/
319
320 acpi_status
321 acpi_ns_attach_data(struct acpi_namespace_node *node,
322                     acpi_object_handler handler, void *data)
323 {
324         union acpi_operand_object *prev_obj_desc;
325         union acpi_operand_object *obj_desc;
326         union acpi_operand_object *data_desc;
327
328         /* We only allow one attachment per handler */
329
330         prev_obj_desc = NULL;
331         obj_desc = node->object;
332         while (obj_desc) {
333                 if ((ACPI_GET_OBJECT_TYPE(obj_desc) == ACPI_TYPE_LOCAL_DATA) &&
334                     (obj_desc->data.handler == handler)) {
335                         return (AE_ALREADY_EXISTS);
336                 }
337
338                 prev_obj_desc = obj_desc;
339                 obj_desc = obj_desc->common.next_object;
340         }
341
342         /* Create an internal object for the data */
343
344         data_desc = acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_DATA);
345         if (!data_desc) {
346                 return (AE_NO_MEMORY);
347         }
348
349         data_desc->data.handler = handler;
350         data_desc->data.pointer = data;
351
352         /* Install the data object */
353
354         if (prev_obj_desc) {
355                 prev_obj_desc->common.next_object = data_desc;
356         } else {
357                 node->object = data_desc;
358         }
359
360         return (AE_OK);
361 }
362
363 /*******************************************************************************
364  *
365  * FUNCTION:    acpi_ns_detach_data
366  *
367  * PARAMETERS:  Node            - Namespace node
368  *              Handler         - Handler associated with the data
369  *
370  * RETURN:      Status
371  *
372  * DESCRIPTION: Low-level detach data.  Delete the data node, but the caller
373  *              is responsible for the actual data.
374  *
375  ******************************************************************************/
376
377 acpi_status
378 acpi_ns_detach_data(struct acpi_namespace_node * node,
379                     acpi_object_handler handler)
380 {
381         union acpi_operand_object *obj_desc;
382         union acpi_operand_object *prev_obj_desc;
383
384         prev_obj_desc = NULL;
385         obj_desc = node->object;
386         while (obj_desc) {
387                 if ((ACPI_GET_OBJECT_TYPE(obj_desc) == ACPI_TYPE_LOCAL_DATA) &&
388                     (obj_desc->data.handler == handler)) {
389                         if (prev_obj_desc) {
390                                 prev_obj_desc->common.next_object =
391                                     obj_desc->common.next_object;
392                         } else {
393                                 node->object = obj_desc->common.next_object;
394                         }
395
396                         acpi_ut_remove_reference(obj_desc);
397                         return (AE_OK);
398                 }
399
400                 prev_obj_desc = obj_desc;
401                 obj_desc = obj_desc->common.next_object;
402         }
403
404         return (AE_NOT_FOUND);
405 }
406
407 /*******************************************************************************
408  *
409  * FUNCTION:    acpi_ns_get_attached_data
410  *
411  * PARAMETERS:  Node            - Namespace node
412  *              Handler         - Handler associated with the data
413  *              Data            - Where the data is returned
414  *
415  * RETURN:      Status
416  *
417  * DESCRIPTION: Low level interface to obtain data previously associated with
418  *              a namespace node.
419  *
420  ******************************************************************************/
421
422 acpi_status
423 acpi_ns_get_attached_data(struct acpi_namespace_node * node,
424                           acpi_object_handler handler, void **data)
425 {
426         union acpi_operand_object *obj_desc;
427
428         obj_desc = node->object;
429         while (obj_desc) {
430                 if ((ACPI_GET_OBJECT_TYPE(obj_desc) == ACPI_TYPE_LOCAL_DATA) &&
431                     (obj_desc->data.handler == handler)) {
432                         *data = obj_desc->data.pointer;
433                         return (AE_OK);
434                 }
435
436                 obj_desc = obj_desc->common.next_object;
437         }
438
439         return (AE_NOT_FOUND);
440 }