err.no Git - linux-2.6/blob - 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 - 2006, R. Byron Moore
  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 }