[CPUFREQ] If max_freq got reduced (e.g. by _PPC) a write to sysfs scaling_governor...
[linux-2.6] / drivers / acpi / executer / exstoren.c
1
2 /******************************************************************************
3  *
4  * Module Name: exstoren - AML Interpreter object store support,
5  *                        Store to Node (namespace object)
6  *
7  *****************************************************************************/
8
9 /*
10  * Copyright (C) 2000 - 2006, R. Byron Moore
11  * All rights reserved.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions, and the following disclaimer,
18  *    without modification.
19  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
20  *    substantially similar to the "NO WARRANTY" disclaimer below
21  *    ("Disclaimer") and any redistribution must be conditioned upon
22  *    including a substantially similar Disclaimer requirement for further
23  *    binary redistribution.
24  * 3. Neither the names of the above-listed copyright holders nor the names
25  *    of any contributors may be used to endorse or promote products derived
26  *    from this software without specific prior written permission.
27  *
28  * Alternatively, this software may be distributed under the terms of the
29  * GNU General Public License ("GPL") version 2 as published by the Free
30  * Software Foundation.
31  *
32  * NO WARRANTY
33  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
34  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
35  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
36  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
37  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
38  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
39  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
40  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
41  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
42  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
43  * POSSIBILITY OF SUCH DAMAGES.
44  */
45
46 #include <acpi/acpi.h>
47 #include <acpi/acinterp.h>
48 #include <acpi/amlcode.h>
49
50 #define _COMPONENT          ACPI_EXECUTER
51 ACPI_MODULE_NAME("exstoren")
52
53 /*******************************************************************************
54  *
55  * FUNCTION:    acpi_ex_resolve_object
56  *
57  * PARAMETERS:  source_desc_ptr     - Pointer to the source object
58  *              target_type         - Current type of the target
59  *              walk_state          - Current walk state
60  *
61  * RETURN:      Status, resolved object in source_desc_ptr.
62  *
63  * DESCRIPTION: Resolve an object.  If the object is a reference, dereference
64  *              it and return the actual object in the source_desc_ptr.
65  *
66  ******************************************************************************/
67 acpi_status
68 acpi_ex_resolve_object(union acpi_operand_object **source_desc_ptr,
69                        acpi_object_type target_type,
70                        struct acpi_walk_state *walk_state)
71 {
72         union acpi_operand_object *source_desc = *source_desc_ptr;
73         acpi_status status = AE_OK;
74
75         ACPI_FUNCTION_TRACE("ex_resolve_object");
76
77         /* Ensure we have a Target that can be stored to */
78
79         switch (target_type) {
80         case ACPI_TYPE_BUFFER_FIELD:
81         case ACPI_TYPE_LOCAL_REGION_FIELD:
82         case ACPI_TYPE_LOCAL_BANK_FIELD:
83         case ACPI_TYPE_LOCAL_INDEX_FIELD:
84                 /*
85                  * These cases all require only Integers or values that
86                  * can be converted to Integers (Strings or Buffers)
87                  */
88
89         case ACPI_TYPE_INTEGER:
90         case ACPI_TYPE_STRING:
91         case ACPI_TYPE_BUFFER:
92
93                 /*
94                  * Stores into a Field/Region or into a Integer/Buffer/String
95                  * are all essentially the same.  This case handles the
96                  * "interchangeable" types Integer, String, and Buffer.
97                  */
98                 if (ACPI_GET_OBJECT_TYPE(source_desc) ==
99                     ACPI_TYPE_LOCAL_REFERENCE) {
100                         /* Resolve a reference object first */
101
102                         status =
103                             acpi_ex_resolve_to_value(source_desc_ptr,
104                                                      walk_state);
105                         if (ACPI_FAILURE(status)) {
106                                 break;
107                         }
108                 }
109
110                 /* For copy_object, no further validation necessary */
111
112                 if (walk_state->opcode == AML_COPY_OP) {
113                         break;
114                 }
115
116                 /* Must have a Integer, Buffer, or String */
117
118                 if ((ACPI_GET_OBJECT_TYPE(source_desc) != ACPI_TYPE_INTEGER) &&
119                     (ACPI_GET_OBJECT_TYPE(source_desc) != ACPI_TYPE_BUFFER) &&
120                     (ACPI_GET_OBJECT_TYPE(source_desc) != ACPI_TYPE_STRING) &&
121                     !((ACPI_GET_OBJECT_TYPE(source_desc) ==
122                        ACPI_TYPE_LOCAL_REFERENCE)
123                       && (source_desc->reference.opcode == AML_LOAD_OP))) {
124                         /* Conversion successful but still not a valid type */
125
126                         ACPI_ERROR((AE_INFO,
127                                     "Cannot assign type %s to %s (must be type Int/Str/Buf)",
128                                     acpi_ut_get_object_type_name(source_desc),
129                                     acpi_ut_get_type_name(target_type)));
130                         status = AE_AML_OPERAND_TYPE;
131                 }
132                 break;
133
134         case ACPI_TYPE_LOCAL_ALIAS:
135         case ACPI_TYPE_LOCAL_METHOD_ALIAS:
136
137                 /*
138                  * All aliases should have been resolved earlier, during the
139                  * operand resolution phase.
140                  */
141                 ACPI_ERROR((AE_INFO, "Store into an unresolved Alias object"));
142                 status = AE_AML_INTERNAL;
143                 break;
144
145         case ACPI_TYPE_PACKAGE:
146         default:
147
148                 /*
149                  * All other types than Alias and the various Fields come here,
150                  * including the untyped case - ACPI_TYPE_ANY.
151                  */
152                 break;
153         }
154
155         return_ACPI_STATUS(status);
156 }
157
158 /*******************************************************************************
159  *
160  * FUNCTION:    acpi_ex_store_object_to_object
161  *
162  * PARAMETERS:  source_desc         - Object to store
163  *              dest_desc           - Object to receive a copy of the source
164  *              new_desc            - New object if dest_desc is obsoleted
165  *              walk_state          - Current walk state
166  *
167  * RETURN:      Status
168  *
169  * DESCRIPTION: "Store" an object to another object.  This may include
170  *              converting the source type to the target type (implicit
171  *              conversion), and a copy of the value of the source to
172  *              the target.
173  *
174  *              The Assignment of an object to another (not named) object
175  *              is handled here.
176  *              The Source passed in will replace the current value (if any)
177  *              with the input value.
178  *
179  *              When storing into an object the data is converted to the
180  *              target object type then stored in the object.  This means
181  *              that the target object type (for an initialized target) will
182  *              not be changed by a store operation.
183  *
184  *              This module allows destination types of Number, String,
185  *              Buffer, and Package.
186  *
187  *              Assumes parameters are already validated.  NOTE: source_desc
188  *              resolution (from a reference object) must be performed by
189  *              the caller if necessary.
190  *
191  ******************************************************************************/
192
193 acpi_status
194 acpi_ex_store_object_to_object(union acpi_operand_object *source_desc,
195                                union acpi_operand_object *dest_desc,
196                                union acpi_operand_object **new_desc,
197                                struct acpi_walk_state *walk_state)
198 {
199         union acpi_operand_object *actual_src_desc;
200         acpi_status status = AE_OK;
201
202         ACPI_FUNCTION_TRACE_PTR("ex_store_object_to_object", source_desc);
203
204         actual_src_desc = source_desc;
205         if (!dest_desc) {
206                 /*
207                  * There is no destination object (An uninitialized node or
208                  * package element), so we can simply copy the source object
209                  * creating a new destination object
210                  */
211                 status =
212                     acpi_ut_copy_iobject_to_iobject(actual_src_desc, new_desc,
213                                                     walk_state);
214                 return_ACPI_STATUS(status);
215         }
216
217         if (ACPI_GET_OBJECT_TYPE(source_desc) !=
218             ACPI_GET_OBJECT_TYPE(dest_desc)) {
219                 /*
220                  * The source type does not match the type of the destination.
221                  * Perform the "implicit conversion" of the source to the current type
222                  * of the target as per the ACPI specification.
223                  *
224                  * If no conversion performed, actual_src_desc = source_desc.
225                  * Otherwise, actual_src_desc is a temporary object to hold the
226                  * converted object.
227                  */
228                 status =
229                     acpi_ex_convert_to_target_type(ACPI_GET_OBJECT_TYPE
230                                                    (dest_desc), source_desc,
231                                                    &actual_src_desc,
232                                                    walk_state);
233                 if (ACPI_FAILURE(status)) {
234                         return_ACPI_STATUS(status);
235                 }
236
237                 if (source_desc == actual_src_desc) {
238                         /*
239                          * No conversion was performed. Return the source_desc as the
240                          * new object.
241                          */
242                         *new_desc = source_desc;
243                         return_ACPI_STATUS(AE_OK);
244                 }
245         }
246
247         /*
248          * We now have two objects of identical types, and we can perform a
249          * copy of the *value* of the source object.
250          */
251         switch (ACPI_GET_OBJECT_TYPE(dest_desc)) {
252         case ACPI_TYPE_INTEGER:
253
254                 dest_desc->integer.value = actual_src_desc->integer.value;
255
256                 /* Truncate value if we are executing from a 32-bit ACPI table */
257
258                 acpi_ex_truncate_for32bit_table(dest_desc);
259                 break;
260
261         case ACPI_TYPE_STRING:
262
263                 status =
264                     acpi_ex_store_string_to_string(actual_src_desc, dest_desc);
265                 break;
266
267         case ACPI_TYPE_BUFFER:
268
269                 status =
270                     acpi_ex_store_buffer_to_buffer(actual_src_desc, dest_desc);
271                 break;
272
273         case ACPI_TYPE_PACKAGE:
274
275                 status =
276                     acpi_ut_copy_iobject_to_iobject(actual_src_desc, &dest_desc,
277                                                     walk_state);
278                 break;
279
280         default:
281                 /*
282                  * All other types come here.
283                  */
284                 ACPI_WARNING((AE_INFO, "Store into type %s not implemented",
285                               acpi_ut_get_object_type_name(dest_desc)));
286
287                 status = AE_NOT_IMPLEMENTED;
288                 break;
289         }
290
291         if (actual_src_desc != source_desc) {
292                 /* Delete the intermediate (temporary) source object */
293
294                 acpi_ut_remove_reference(actual_src_desc);
295         }
296
297         *new_desc = dest_desc;
298         return_ACPI_STATUS(status);
299 }