drivers/acpi/acpica/evregion.c

   1 /******************************************************************************
   2  *
   3  * Module Name: evregion - Operation Region support
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2013, Intel Corp.
   9  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions, and the following disclaimer,
  16  *    without modification.
  17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  18  *    substantially similar to the "NO WARRANTY" disclaimer below
  19  *    ("Disclaimer") and any redistribution must be conditioned upon
  20  *    including a substantially similar Disclaimer requirement for further
  21  *    binary redistribution.
  22  * 3. Neither the names of the above-listed copyright holders nor the names
  23  *    of any contributors may be used to endorse or promote products derived
  24  *    from this software without specific prior written permission.
  25  *
  26  * Alternatively, this software may be distributed under the terms of the
  27  * GNU General Public License ("GPL") version 2 as published by the Free
  28  * Software Foundation.
  29  *
  30  * NO WARRANTY
  31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  41  * POSSIBILITY OF SUCH DAMAGES.
  42  */
  43
  44 #include <acpi/acpi.h>
  45 #include "accommon.h"
  46 #include "acevents.h"
  47 #include "acnamesp.h"
  48 #include "acinterp.h"
  49
  50 #define _COMPONENT          ACPI_EVENTS
  51 ACPI_MODULE_NAME("evregion")
  52
  53 extern u8 acpi_gbl_default_address_spaces[];
  54
  55 /* Local prototypes */
  56
  57 static void acpi_ev_orphan_ec_reg_method(void);
  58
  59 static acpi_status
  60 acpi_ev_reg_run(acpi_handle obj_handle,
  61                 u32 level, void *context, void **return_value);
  62
  63 /*******************************************************************************
  64  *
  65  * FUNCTION:    acpi_ev_initialize_op_regions
  66  *
  67  * PARAMETERS:  None
  68  *
  69  * RETURN:      Status
  70  *
  71  * DESCRIPTION: Execute _REG methods for all Operation Regions that have
  72  *              an installed default region handler.
  73  *
  74  ******************************************************************************/
  75
  76 acpi_status acpi_ev_initialize_op_regions(void)
  77 {
  78         acpi_status status;
  79         u32 i;
  80
  81         ACPI_FUNCTION_TRACE(ev_initialize_op_regions);
  82
  83         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
  84         if (ACPI_FAILURE(status)) {
  85                 return_ACPI_STATUS(status);
  86         }
  87
  88         /* Run the _REG methods for op_regions in each default address space */
  89
  90         for (i = 0; i < ACPI_NUM_DEFAULT_SPACES; i++) {
  91                 /*
  92                  * Make sure the installed handler is the DEFAULT handler. If not the
  93                  * default, the _REG methods will have already been run (when the
  94                  * handler was installed)
  95                  */
  96                 if (acpi_ev_has_default_handler(acpi_gbl_root_node,
  97                                                 acpi_gbl_default_address_spaces
  98                                                 [i])) {
  99                         status =
 100                             acpi_ev_execute_reg_methods(acpi_gbl_root_node,
 101                                                         acpi_gbl_default_address_spaces
 102                                                         [i]);
 103                 }
 104         }
 105
 106         acpi_gbl_reg_methods_executed = TRUE;
 107
 108         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 109         return_ACPI_STATUS(status);
 110 }
 111
 112 /*******************************************************************************
 113  *
 114  * FUNCTION:    acpi_ev_address_space_dispatch
 115  *
 116  * PARAMETERS:  region_obj          - Internal region object
 117  *              field_obj           - Corresponding field. Can be NULL.
 118  *              function            - Read or Write operation
 119  *              region_offset       - Where in the region to read or write
 120  *              bit_width           - Field width in bits (8, 16, 32, or 64)
 121  *              value               - Pointer to in or out value, must be
 122  *                                    a full 64-bit integer
 123  *
 124  * RETURN:      Status
 125  *
 126  * DESCRIPTION: Dispatch an address space or operation region access to
 127  *              a previously installed handler.
 128  *
 129  ******************************************************************************/
 130
 131 acpi_status
 132 acpi_ev_address_space_dispatch(union acpi_operand_object *region_obj,
 133                                union acpi_operand_object *field_obj,
 134                                u32 function,
 135                                u32 region_offset, u32 bit_width, u64 *value)
 136 {
 137         acpi_status status;
 138         acpi_adr_space_handler handler;
 139         acpi_adr_space_setup region_setup;
 140         union acpi_operand_object *handler_desc;
 141         union acpi_operand_object *region_obj2;
 142         void *region_context = NULL;
 143         struct acpi_connection_info *context;
 144         acpi_physical_address address;
 145
 146         ACPI_FUNCTION_TRACE(ev_address_space_dispatch);
 147
 148         region_obj2 = acpi_ns_get_secondary_object(region_obj);
 149         if (!region_obj2) {
 150                 return_ACPI_STATUS(AE_NOT_EXIST);
 151         }
 152
 153         /* Ensure that there is a handler associated with this region */
 154
 155         handler_desc = region_obj->region.handler;
 156         if (!handler_desc) {
 157                 ACPI_ERROR((AE_INFO,
 158                             "No handler for Region [%4.4s] (%p) [%s]",
 159                             acpi_ut_get_node_name(region_obj->region.node),
 160                             region_obj,
 161                             acpi_ut_get_region_name(region_obj->region.
 162                                                     space_id)));
 163
 164                 return_ACPI_STATUS(AE_NOT_EXIST);
 165         }
 166
 167         context = handler_desc->address_space.context;
 168
 169         /*
 170          * It may be the case that the region has never been initialized.
 171          * Some types of regions require special init code
 172          */
 173         if (!(region_obj->region.flags & AOPOBJ_SETUP_COMPLETE)) {
 174
 175                 /* This region has not been initialized yet, do it */
 176
 177                 region_setup = handler_desc->address_space.setup;
 178                 if (!region_setup) {
 179
 180                         /* No initialization routine, exit with error */
 181
 182                         ACPI_ERROR((AE_INFO,
 183                                     "No init routine for region(%p) [%s]",
 184                                     region_obj,
 185                                     acpi_ut_get_region_name(region_obj->region.
 186                                                             space_id)));
 187                         return_ACPI_STATUS(AE_NOT_EXIST);
 188                 }
 189
 190                 /*
 191                  * We must exit the interpreter because the region setup will
 192                  * potentially execute control methods (for example, the _REG method
 193                  * for this region)
 194                  */
 195                 acpi_ex_exit_interpreter();
 196
 197                 status = region_setup(region_obj, ACPI_REGION_ACTIVATE,
 198                                       context, &region_context);
 199
 200                 /* Re-enter the interpreter */
 201
 202                 acpi_ex_enter_interpreter();
 203
 204                 /* Check for failure of the Region Setup */
 205
 206                 if (ACPI_FAILURE(status)) {
 207                         ACPI_EXCEPTION((AE_INFO, status,
 208                                         "During region initialization: [%s]",
 209                                         acpi_ut_get_region_name(region_obj->
 210                                                                 region.
 211                                                                 space_id)));
 212                         return_ACPI_STATUS(status);
 213                 }
 214
 215                 /* Region initialization may have been completed by region_setup */
 216
 217                 if (!(region_obj->region.flags & AOPOBJ_SETUP_COMPLETE)) {
 218                         region_obj->region.flags |= AOPOBJ_SETUP_COMPLETE;
 219
 220                         if (region_obj2->extra.region_context) {
 221
 222                                 /* The handler for this region was already installed */
 223
 224                                 ACPI_FREE(region_context);
 225                         } else {
 226                                 /*
 227                                  * Save the returned context for use in all accesses to
 228                                  * this particular region
 229                                  */
 230                                 region_obj2->extra.region_context =
 231                                     region_context;
 232                         }
 233                 }
 234         }
 235
 236         /* We have everything we need, we can invoke the address space handler */
 237
 238         handler = handler_desc->address_space.handler;
 239         address = (region_obj->region.address + region_offset);
 240
 241         /*
 242          * Special handling for generic_serial_bus and general_purpose_io:
 243          * There are three extra parameters that must be passed to the
 244          * handler via the context:
 245          *   1) Connection buffer, a resource template from Connection() op
 246          *   2) Length of the above buffer
 247          *   3) Actual access length from the access_as() op
 248          *
 249          * In addition, for general_purpose_io, the Address and bit_width fields
 250          * are defined as follows:
 251          *   1) Address is the pin number index of the field (bit offset from
 252          *      the previous Connection)
 253          *   2) bit_width is the actual bit length of the field (number of pins)
 254          */
 255         if ((region_obj->region.space_id == ACPI_ADR_SPACE_GSBUS) &&
 256             context && field_obj) {
 257
 258                 /* Get the Connection (resource_template) buffer */
 259
 260                 context->connection = field_obj->field.resource_buffer;
 261                 context->length = field_obj->field.resource_length;
 262                 context->access_length = field_obj->field.access_length;
 263         }
 264         if ((region_obj->region.space_id == ACPI_ADR_SPACE_GPIO) &&
 265             context && field_obj) {
 266
 267                 /* Get the Connection (resource_template) buffer */
 268
 269                 context->connection = field_obj->field.resource_buffer;
 270                 context->length = field_obj->field.resource_length;
 271                 context->access_length = field_obj->field.access_length;
 272                 address = field_obj->field.pin_number_index;
 273                 bit_width = field_obj->field.bit_length;
 274         }
 275
 276         ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
 277                           "Handler %p (@%p) Address %8.8X%8.8X [%s]\n",
 278                           &region_obj->region.handler->address_space, handler,
 279                           ACPI_FORMAT_NATIVE_UINT(address),
 280                           acpi_ut_get_region_name(region_obj->region.
 281                                                   space_id)));
 282
 283         if (!(handler_desc->address_space.handler_flags &
 284               ACPI_ADDR_HANDLER_DEFAULT_INSTALLED)) {
 285                 /*
 286                  * For handlers other than the default (supplied) handlers, we must
 287                  * exit the interpreter because the handler *might* block -- we don't
 288                  * know what it will do, so we can't hold the lock on the intepreter.
 289                  */
 290                 acpi_ex_exit_interpreter();
 291         }
 292
 293         /* Call the handler */
 294
 295         status = handler(function, address, bit_width, value, context,
 296                          region_obj2->extra.region_context);
 297
 298         if (ACPI_FAILURE(status)) {
 299                 ACPI_EXCEPTION((AE_INFO, status, "Returned by Handler for [%s]",
 300                                 acpi_ut_get_region_name(region_obj->region.
 301                                                         space_id)));
 302         }
 303
 304         if (!(handler_desc->address_space.handler_flags &
 305               ACPI_ADDR_HANDLER_DEFAULT_INSTALLED)) {
 306                 /*
 307                  * We just returned from a non-default handler, we must re-enter the
 308                  * interpreter
 309                  */
 310                 acpi_ex_enter_interpreter();
 311         }
 312
 313         return_ACPI_STATUS(status);
 314 }
 315
 316 /*******************************************************************************
 317  *
 318  * FUNCTION:    acpi_ev_detach_region
 319  *
 320  * PARAMETERS:  region_obj          - Region Object
 321  *              acpi_ns_is_locked   - Namespace Region Already Locked?
 322  *
 323  * RETURN:      None
 324  *
 325  * DESCRIPTION: Break the association between the handler and the region
 326  *              this is a two way association.
 327  *
 328  ******************************************************************************/
 329
 330 void
 331 acpi_ev_detach_region(union acpi_operand_object *region_obj,
 332                       u8 acpi_ns_is_locked)
 333 {
 334         union acpi_operand_object *handler_obj;
 335         union acpi_operand_object *obj_desc;
 336         union acpi_operand_object **last_obj_ptr;
 337         acpi_adr_space_setup region_setup;
 338         void **region_context;
 339         union acpi_operand_object *region_obj2;
 340         acpi_status status;
 341
 342         ACPI_FUNCTION_TRACE(ev_detach_region);
 343
 344         region_obj2 = acpi_ns_get_secondary_object(region_obj);
 345         if (!region_obj2) {
 346                 return_VOID;
 347         }
 348         region_context = &region_obj2->extra.region_context;
 349
 350         /* Get the address handler from the region object */
 351
 352         handler_obj = region_obj->region.handler;
 353         if (!handler_obj) {
 354
 355                 /* This region has no handler, all done */
 356
 357                 return_VOID;
 358         }
 359
 360         /* Find this region in the handler's list */
 361
 362         obj_desc = handler_obj->address_space.region_list;
 363         last_obj_ptr = &handler_obj->address_space.region_list;
 364
 365         while (obj_desc) {
 366
 367                 /* Is this the correct Region? */
 368
 369                 if (obj_desc == region_obj) {
 370                         ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
 371                                           "Removing Region %p from address handler %p\n",
 372                                           region_obj, handler_obj));
 373
 374                         /* This is it, remove it from the handler's list */
 375
 376                         *last_obj_ptr = obj_desc->region.next;
 377                         obj_desc->region.next = NULL;   /* Must clear field */
 378
 379                         if (acpi_ns_is_locked) {
 380                                 status =
 381                                     acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 382                                 if (ACPI_FAILURE(status)) {
 383                                         return_VOID;
 384                                 }
 385                         }
 386
 387                         /* Now stop region accesses by executing the _REG method */
 388
 389                         status =
 390                             acpi_ev_execute_reg_method(region_obj,
 391                                                        ACPI_REG_DISCONNECT);
 392                         if (ACPI_FAILURE(status)) {
 393                                 ACPI_EXCEPTION((AE_INFO, status,
 394                                                 "from region _REG, [%s]",
 395                                                 acpi_ut_get_region_name
 396                                                 (region_obj->region.space_id)));
 397                         }
 398
 399                         if (acpi_ns_is_locked) {
 400                                 status =
 401                                     acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 402                                 if (ACPI_FAILURE(status)) {
 403                                         return_VOID;
 404                                 }
 405                         }
 406
 407                         /*
 408                          * If the region has been activated, call the setup handler with
 409                          * the deactivate notification
 410                          */
 411                         if (region_obj->region.flags & AOPOBJ_SETUP_COMPLETE) {
 412                                 region_setup = handler_obj->address_space.setup;
 413                                 status =
 414                                     region_setup(region_obj,
 415                                                  ACPI_REGION_DEACTIVATE,
 416                                                  handler_obj->address_space.
 417                                                  context, region_context);
 418
 419                                 /* Init routine may fail, Just ignore errors */
 420
 421                                 if (ACPI_FAILURE(status)) {
 422                                         ACPI_EXCEPTION((AE_INFO, status,
 423                                                         "from region handler - deactivate, [%s]",
 424                                                         acpi_ut_get_region_name
 425                                                         (region_obj->region.
 426                                                          space_id)));
 427                                 }
 428
 429                                 region_obj->region.flags &=
 430                                     ~(AOPOBJ_SETUP_COMPLETE);
 431                         }
 432
 433                         /*
 434                          * Remove handler reference in the region
 435                          *
 436                          * NOTE: this doesn't mean that the region goes away, the region
 437                          * is just inaccessible as indicated to the _REG method
 438                          *
 439                          * If the region is on the handler's list, this must be the
 440                          * region's handler
 441                          */
 442                         region_obj->region.handler = NULL;
 443                         acpi_ut_remove_reference(handler_obj);
 444
 445                         return_VOID;
 446                 }
 447
 448                 /* Walk the linked list of handlers */
 449
 450                 last_obj_ptr = &obj_desc->region.next;
 451                 obj_desc = obj_desc->region.next;
 452         }
 453
 454         /* If we get here, the region was not in the handler's region list */
 455
 456         ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
 457                           "Cannot remove region %p from address handler %p\n",
 458                           region_obj, handler_obj));
 459
 460         return_VOID;
 461 }
 462
 463 /*******************************************************************************
 464  *
 465  * FUNCTION:    acpi_ev_attach_region
 466  *
 467  * PARAMETERS:  handler_obj         - Handler Object
 468  *              region_obj          - Region Object
 469  *              acpi_ns_is_locked   - Namespace Region Already Locked?
 470  *
 471  * RETURN:      None
 472  *
 473  * DESCRIPTION: Create the association between the handler and the region
 474  *              this is a two way association.
 475  *
 476  ******************************************************************************/
 477
 478 acpi_status
 479 acpi_ev_attach_region(union acpi_operand_object *handler_obj,
 480                       union acpi_operand_object *region_obj,
 481                       u8 acpi_ns_is_locked)
 482 {
 483
 484         ACPI_FUNCTION_TRACE(ev_attach_region);
 485
 486         ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
 487                           "Adding Region [%4.4s] %p to address handler %p [%s]\n",
 488                           acpi_ut_get_node_name(region_obj->region.node),
 489                           region_obj, handler_obj,
 490                           acpi_ut_get_region_name(region_obj->region.
 491                                                   space_id)));
 492
 493         /* Link this region to the front of the handler's list */
 494
 495         region_obj->region.next = handler_obj->address_space.region_list;
 496         handler_obj->address_space.region_list = region_obj;
 497
 498         /* Install the region's handler */
 499
 500         if (region_obj->region.handler) {
 501                 return_ACPI_STATUS(AE_ALREADY_EXISTS);
 502         }
 503
 504         region_obj->region.handler = handler_obj;
 505         acpi_ut_add_reference(handler_obj);
 506
 507         return_ACPI_STATUS(AE_OK);
 508 }
 509
 510 /*******************************************************************************
 511  *
 512  * FUNCTION:    acpi_ev_execute_reg_method
 513  *
 514  * PARAMETERS:  region_obj          - Region object
 515  *              function            - Passed to _REG: On (1) or Off (0)
 516  *
 517  * RETURN:      Status
 518  *
 519  * DESCRIPTION: Execute _REG method for a region
 520  *
 521  ******************************************************************************/
 522
 523 acpi_status
 524 acpi_ev_execute_reg_method(union acpi_operand_object *region_obj, u32 function)
 525 {
 526         struct acpi_evaluate_info *info;
 527         union acpi_operand_object *args[3];
 528         union acpi_operand_object *region_obj2;
 529         acpi_status status;
 530
 531         ACPI_FUNCTION_TRACE(ev_execute_reg_method);
 532
 533         region_obj2 = acpi_ns_get_secondary_object(region_obj);
 534         if (!region_obj2) {
 535                 return_ACPI_STATUS(AE_NOT_EXIST);
 536         }
 537
 538         if (region_obj2->extra.method_REG == NULL) {
 539                 return_ACPI_STATUS(AE_OK);
 540         }
 541
 542         /* Allocate and initialize the evaluation information block */
 543
 544         info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
 545         if (!info) {
 546                 return_ACPI_STATUS(AE_NO_MEMORY);
 547         }
 548
 549         info->prefix_node = region_obj2->extra.method_REG;
 550         info->pathname = NULL;
 551         info->parameters = args;
 552         info->flags = ACPI_IGNORE_RETURN_VALUE;
 553
 554         /*
 555          * The _REG method has two arguments:
 556          *
 557          * arg0 - Integer:
 558          *  Operation region space ID Same value as region_obj->Region.space_id
 559          *
 560          * arg1 - Integer:
 561          *  connection status 1 for connecting the handler, 0 for disconnecting
 562          *  the handler (Passed as a parameter)
 563          */
 564         args[0] =
 565             acpi_ut_create_integer_object((u64)region_obj->region.space_id);
 566         if (!args[0]) {
 567                 status = AE_NO_MEMORY;
 568                 goto cleanup1;
 569         }
 570
 571         args[1] = acpi_ut_create_integer_object((u64)function);
 572         if (!args[1]) {
 573                 status = AE_NO_MEMORY;
 574                 goto cleanup2;
 575         }
 576
 577         args[2] = NULL;         /* Terminate list */
 578
 579         /* Execute the method, no return value */
 580
 581         ACPI_DEBUG_EXEC(acpi_ut_display_init_pathname
 582                         (ACPI_TYPE_METHOD, info->prefix_node, NULL));
 583
 584         status = acpi_ns_evaluate(info);
 585         acpi_ut_remove_reference(args[1]);
 586
 587       cleanup2:
 588         acpi_ut_remove_reference(args[0]);
 589
 590       cleanup1:
 591         ACPI_FREE(info);
 592         return_ACPI_STATUS(status);
 593 }
 594
 595 /*******************************************************************************
 596  *
 597  * FUNCTION:    acpi_ev_execute_reg_methods
 598  *
 599  * PARAMETERS:  node            - Namespace node for the device
 600  *              space_id        - The address space ID
 601  *
 602  * RETURN:      Status
 603  *
 604  * DESCRIPTION: Run all _REG methods for the input Space ID;
 605  *              Note: assumes namespace is locked, or system init time.
 606  *
 607  ******************************************************************************/
 608
 609 acpi_status
 610 acpi_ev_execute_reg_methods(struct acpi_namespace_node *node,
 611                             acpi_adr_space_type space_id)
 612 {
 613         acpi_status status;
 614
 615         ACPI_FUNCTION_TRACE(ev_execute_reg_methods);
 616
 617         /*
 618          * Run all _REG methods for all Operation Regions for this space ID. This
 619          * is a separate walk in order to handle any interdependencies between
 620          * regions and _REG methods. (i.e. handlers must be installed for all
 621          * regions of this Space ID before we can run any _REG methods)
 622          */
 623         status = acpi_ns_walk_namespace(ACPI_TYPE_ANY, node, ACPI_UINT32_MAX,
 624                                         ACPI_NS_WALK_UNLOCK, acpi_ev_reg_run,
 625                                         NULL, &space_id, NULL);
 626
 627         /* Special case for EC: handle "orphan" _REG methods with no region */
 628
 629         if (space_id == ACPI_ADR_SPACE_EC) {
 630                 acpi_ev_orphan_ec_reg_method();
 631         }
 632
 633         return_ACPI_STATUS(status);
 634 }
 635
 636 /*******************************************************************************
 637  *
 638  * FUNCTION:    acpi_ev_reg_run
 639  *
 640  * PARAMETERS:  walk_namespace callback
 641  *
 642  * DESCRIPTION: Run _REG method for region objects of the requested spaceID
 643  *
 644  ******************************************************************************/
 645
 646 static acpi_status
 647 acpi_ev_reg_run(acpi_handle obj_handle,
 648                 u32 level, void *context, void **return_value)
 649 {
 650         union acpi_operand_object *obj_desc;
 651         struct acpi_namespace_node *node;
 652         acpi_adr_space_type space_id;
 653         acpi_status status;
 654
 655         space_id = *ACPI_CAST_PTR(acpi_adr_space_type, context);
 656
 657         /* Convert and validate the device handle */
 658
 659         node = acpi_ns_validate_handle(obj_handle);
 660         if (!node) {
 661                 return (AE_BAD_PARAMETER);
 662         }
 663
 664         /*
 665          * We only care about regions.and objects that are allowed to have address
 666          * space handlers
 667          */
 668         if ((node->type != ACPI_TYPE_REGION) && (node != acpi_gbl_root_node)) {
 669                 return (AE_OK);
 670         }
 671
 672         /* Check for an existing internal object */
 673
 674         obj_desc = acpi_ns_get_attached_object(node);
 675         if (!obj_desc) {
 676
 677                 /* No object, just exit */
 678
 679                 return (AE_OK);
 680         }
 681
 682         /* Object is a Region */
 683
 684         if (obj_desc->region.space_id != space_id) {
 685
 686                 /* This region is for a different address space, just ignore it */
 687
 688                 return (AE_OK);
 689         }
 690
 691         status = acpi_ev_execute_reg_method(obj_desc, ACPI_REG_CONNECT);
 692         return (status);
 693 }
 694
 695 /*******************************************************************************
 696  *
 697  * FUNCTION:    acpi_ev_orphan_ec_reg_method
 698  *
 699  * PARAMETERS:  None
 700  *
 701  * RETURN:      None
 702  *
 703  * DESCRIPTION: Execute an "orphan" _REG method that appears under the EC
 704  *              device. This is a _REG method that has no corresponding region
 705  *              within the EC device scope. The orphan _REG method appears to
 706  *              have been enabled by the description of the ECDT in the ACPI
 707  *              specification: "The availability of the region space can be
 708  *              detected by providing a _REG method object underneath the
 709  *              Embedded Controller device."
 710  *
 711  *              To quickly access the EC device, we use the EC_ID that appears
 712  *              within the ECDT. Otherwise, we would need to perform a time-
 713  *              consuming namespace walk, executing _HID methods to find the
 714  *              EC device.
 715  *
 716  ******************************************************************************/
 717
 718 static void acpi_ev_orphan_ec_reg_method(void)
 719 {
 720         struct acpi_table_ecdt *table;
 721         acpi_status status;
 722         struct acpi_object_list args;
 723         union acpi_object objects[2];
 724         struct acpi_namespace_node *ec_device_node;
 725         struct acpi_namespace_node *reg_method;
 726         struct acpi_namespace_node *next_node;
 727
 728         ACPI_FUNCTION_TRACE(ev_orphan_ec_reg_method);
 729
 730         /* Get the ECDT (if present in system) */
 731
 732         status = acpi_get_table(ACPI_SIG_ECDT, 0,
 733                                 ACPI_CAST_INDIRECT_PTR(struct acpi_table_header,
 734                                                        &table));
 735         if (ACPI_FAILURE(status)) {
 736                 return_VOID;
 737         }
 738
 739         /* We need a valid EC_ID string */
 740
 741         if (!(*table->id)) {
 742                 return_VOID;
 743         }
 744
 745         /* Namespace is currently locked, must release */
 746
 747         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 748
 749         /* Get a handle to the EC device referenced in the ECDT */
 750
 751         status = acpi_get_handle(NULL,
 752                                  ACPI_CAST_PTR(char, table->id),
 753                                  ACPI_CAST_PTR(acpi_handle, &ec_device_node));
 754         if (ACPI_FAILURE(status)) {
 755                 goto exit;
 756         }
 757
 758         /* Get a handle to a _REG method immediately under the EC device */
 759
 760         status = acpi_get_handle(ec_device_node,
 761                                  METHOD_NAME__REG, ACPI_CAST_PTR(acpi_handle,
 762                                                                  &reg_method));
 763         if (ACPI_FAILURE(status)) {
 764                 goto exit;
 765         }
 766
 767         /*
 768          * Execute the _REG method only if there is no Operation Region in
 769          * this scope with the Embedded Controller space ID. Otherwise, it
 770          * will already have been executed. Note, this allows for Regions
 771          * with other space IDs to be present; but the code below will then
 772          * execute the _REG method with the EC space ID argument.
 773          */
 774         next_node = acpi_ns_get_next_node(ec_device_node, NULL);
 775         while (next_node) {
 776                 if ((next_node->type == ACPI_TYPE_REGION) &&
 777                     (next_node->object) &&
 778                     (next_node->object->region.space_id == ACPI_ADR_SPACE_EC)) {
 779                         goto exit;      /* Do not execute _REG */
 780                 }
 781                 next_node = acpi_ns_get_next_node(ec_device_node, next_node);
 782         }
 783
 784         /* Evaluate the _REG(EC,Connect) method */
 785
 786         args.count = 2;
 787         args.pointer = objects;
 788         objects[0].type = ACPI_TYPE_INTEGER;
 789         objects[0].integer.value = ACPI_ADR_SPACE_EC;
 790         objects[1].type = ACPI_TYPE_INTEGER;
 791         objects[1].integer.value = ACPI_REG_CONNECT;
 792
 793         status = acpi_evaluate_object(reg_method, NULL, &args, NULL);
 794
 795       exit:
 796         /* We ignore all errors from above, don't care */
 797
 798         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 799         return_VOID;
 800 }