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; 144 145 ACPI_FUNCTION_TRACE(ev_address_space_dispatch); 146 147 region_obj2 = acpi_ns_get_secondary_object(region_obj); 148 if (!region_obj2) { 149 return_ACPI_STATUS(AE_NOT_EXIST); 150 } 151 152 /* Ensure that there is a handler associated with this region */ 153 154 handler_desc = region_obj->region.handler; 155 if (!handler_desc) { 156 ACPI_ERROR((AE_INFO, 157 "No handler for Region [%4.4s] (%p) [%s]", 158 acpi_ut_get_node_name(region_obj->region.node), 159 region_obj, 160 acpi_ut_get_region_name(region_obj->region. 161 space_id))); 162 163 return_ACPI_STATUS(AE_NOT_EXIST); 164 } 165 166 context = handler_desc->address_space.context; 167 168 /* 169 * It may be the case that the region has never been initialized. 170 * Some types of regions require special init code 171 */ 172 if (!(region_obj->region.flags & AOPOBJ_SETUP_COMPLETE)) { 173 174 /* This region has not been initialized yet, do it */ 175 176 region_setup = handler_desc->address_space.setup; 177 if (!region_setup) { 178 179 /* No initialization routine, exit with error */ 180 181 ACPI_ERROR((AE_INFO, 182 "No init routine for region(%p) [%s]", 183 region_obj, 184 acpi_ut_get_region_name(region_obj->region. 185 space_id))); 186 return_ACPI_STATUS(AE_NOT_EXIST); 187 } 188 189 /* 190 * We must exit the interpreter because the region setup will 191 * potentially execute control methods (for example, the _REG method 192 * for this region) 193 */ 194 acpi_ex_exit_interpreter(); 195 196 status = region_setup(region_obj, ACPI_REGION_ACTIVATE, 197 context, ®ion_context); 198 199 /* Re-enter the interpreter */ 200 201 acpi_ex_enter_interpreter(); 202 203 /* Check for failure of the Region Setup */ 204 205 if (ACPI_FAILURE(status)) { 206 ACPI_EXCEPTION((AE_INFO, status, 207 "During region initialization: [%s]", 208 acpi_ut_get_region_name(region_obj-> 209 region. 210 space_id))); 211 return_ACPI_STATUS(status); 212 } 213 214 /* Region initialization may have been completed by region_setup */ 215 216 if (!(region_obj->region.flags & AOPOBJ_SETUP_COMPLETE)) { 217 region_obj->region.flags |= AOPOBJ_SETUP_COMPLETE; 218 219 if (region_obj2->extra.region_context) { 220 221 /* The handler for this region was already installed */ 222 223 ACPI_FREE(region_context); 224 } else { 225 /* 226 * Save the returned context for use in all accesses to 227 * this particular region 228 */ 229 region_obj2->extra.region_context = 230 region_context; 231 } 232 } 233 } 234 235 /* We have everything we need, we can invoke the address space handler */ 236 237 handler = handler_desc->address_space.handler; 238 239 ACPI_DEBUG_PRINT((ACPI_DB_OPREGION, 240 "Handler %p (@%p) Address %8.8X%8.8X [%s]\n", 241 ®ion_obj->region.handler->address_space, handler, 242 ACPI_FORMAT_NATIVE_UINT(region_obj->region.address + 243 region_offset), 244 acpi_ut_get_region_name(region_obj->region. 245 space_id))); 246 247 /* 248 * Special handling for generic_serial_bus and general_purpose_io: 249 * There are three extra parameters that must be passed to the 250 * handler via the context: 251 * 1) Connection buffer, a resource template from Connection() op. 252 * 2) Length of the above buffer. 253 * 3) Actual access length from the access_as() op. 254 */ 255 if (((region_obj->region.space_id == ACPI_ADR_SPACE_GSBUS) || 256 (region_obj->region.space_id == ACPI_ADR_SPACE_GPIO)) && 257 context && field_obj) { 258 259 /* Get the Connection (resource_template) buffer */ 260 261 context->connection = field_obj->field.resource_buffer; 262 context->length = field_obj->field.resource_length; 263 context->access_length = field_obj->field.access_length; 264 } 265 266 if (!(handler_desc->address_space.handler_flags & 267 ACPI_ADDR_HANDLER_DEFAULT_INSTALLED)) { 268 /* 269 * For handlers other than the default (supplied) handlers, we must 270 * exit the interpreter because the handler *might* block -- we don't 271 * know what it will do, so we can't hold the lock on the intepreter. 272 */ 273 acpi_ex_exit_interpreter(); 274 } 275 276 /* Call the handler */ 277 278 status = handler(function, 279 (region_obj->region.address + region_offset), 280 bit_width, value, context, 281 region_obj2->extra.region_context); 282 283 if (ACPI_FAILURE(status)) { 284 ACPI_EXCEPTION((AE_INFO, status, "Returned by Handler for [%s]", 285 acpi_ut_get_region_name(region_obj->region. 286 space_id))); 287 } 288 289 if (!(handler_desc->address_space.handler_flags & 290 ACPI_ADDR_HANDLER_DEFAULT_INSTALLED)) { 291 /* 292 * We just returned from a non-default handler, we must re-enter the 293 * interpreter 294 */ 295 acpi_ex_enter_interpreter(); 296 } 297 298 return_ACPI_STATUS(status); 299 } 300 301 /******************************************************************************* 302 * 303 * FUNCTION: acpi_ev_detach_region 304 * 305 * PARAMETERS: region_obj - Region Object 306 * acpi_ns_is_locked - Namespace Region Already Locked? 307 * 308 * RETURN: None 309 * 310 * DESCRIPTION: Break the association between the handler and the region 311 * this is a two way association. 312 * 313 ******************************************************************************/ 314 315 void 316 acpi_ev_detach_region(union acpi_operand_object *region_obj, 317 u8 acpi_ns_is_locked) 318 { 319 union acpi_operand_object *handler_obj; 320 union acpi_operand_object *obj_desc; 321 union acpi_operand_object **last_obj_ptr; 322 acpi_adr_space_setup region_setup; 323 void **region_context; 324 union acpi_operand_object *region_obj2; 325 acpi_status status; 326 327 ACPI_FUNCTION_TRACE(ev_detach_region); 328 329 region_obj2 = acpi_ns_get_secondary_object(region_obj); 330 if (!region_obj2) { 331 return_VOID; 332 } 333 region_context = ®ion_obj2->extra.region_context; 334 335 /* Get the address handler from the region object */ 336 337 handler_obj = region_obj->region.handler; 338 if (!handler_obj) { 339 340 /* This region has no handler, all done */ 341 342 return_VOID; 343 } 344 345 /* Find this region in the handler's list */ 346 347 obj_desc = handler_obj->address_space.region_list; 348 last_obj_ptr = &handler_obj->address_space.region_list; 349 350 while (obj_desc) { 351 352 /* Is this the correct Region? */ 353 354 if (obj_desc == region_obj) { 355 ACPI_DEBUG_PRINT((ACPI_DB_OPREGION, 356 "Removing Region %p from address handler %p\n", 357 region_obj, handler_obj)); 358 359 /* This is it, remove it from the handler's list */ 360 361 *last_obj_ptr = obj_desc->region.next; 362 obj_desc->region.next = NULL; /* Must clear field */ 363 364 if (acpi_ns_is_locked) { 365 status = 366 acpi_ut_release_mutex(ACPI_MTX_NAMESPACE); 367 if (ACPI_FAILURE(status)) { 368 return_VOID; 369 } 370 } 371 372 /* Now stop region accesses by executing the _REG method */ 373 374 status = 375 acpi_ev_execute_reg_method(region_obj, 376 ACPI_REG_DISCONNECT); 377 if (ACPI_FAILURE(status)) { 378 ACPI_EXCEPTION((AE_INFO, status, 379 "from region _REG, [%s]", 380 acpi_ut_get_region_name 381 (region_obj->region.space_id))); 382 } 383 384 if (acpi_ns_is_locked) { 385 status = 386 acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE); 387 if (ACPI_FAILURE(status)) { 388 return_VOID; 389 } 390 } 391 392 /* 393 * If the region has been activated, call the setup handler with 394 * the deactivate notification 395 */ 396 if (region_obj->region.flags & AOPOBJ_SETUP_COMPLETE) { 397 region_setup = handler_obj->address_space.setup; 398 status = 399 region_setup(region_obj, 400 ACPI_REGION_DEACTIVATE, 401 handler_obj->address_space. 402 context, region_context); 403 404 /* Init routine may fail, Just ignore errors */ 405 406 if (ACPI_FAILURE(status)) { 407 ACPI_EXCEPTION((AE_INFO, status, 408 "from region handler - deactivate, [%s]", 409 acpi_ut_get_region_name 410 (region_obj->region. 411 space_id))); 412 } 413 414 region_obj->region.flags &= 415 ~(AOPOBJ_SETUP_COMPLETE); 416 } 417 418 /* 419 * Remove handler reference in the region 420 * 421 * NOTE: this doesn't mean that the region goes away, the region 422 * is just inaccessible as indicated to the _REG method 423 * 424 * If the region is on the handler's list, this must be the 425 * region's handler 426 */ 427 region_obj->region.handler = NULL; 428 acpi_ut_remove_reference(handler_obj); 429 430 return_VOID; 431 } 432 433 /* Walk the linked list of handlers */ 434 435 last_obj_ptr = &obj_desc->region.next; 436 obj_desc = obj_desc->region.next; 437 } 438 439 /* If we get here, the region was not in the handler's region list */ 440 441 ACPI_DEBUG_PRINT((ACPI_DB_OPREGION, 442 "Cannot remove region %p from address handler %p\n", 443 region_obj, handler_obj)); 444 445 return_VOID; 446 } 447 448 /******************************************************************************* 449 * 450 * FUNCTION: acpi_ev_attach_region 451 * 452 * PARAMETERS: handler_obj - Handler Object 453 * region_obj - Region Object 454 * acpi_ns_is_locked - Namespace Region Already Locked? 455 * 456 * RETURN: None 457 * 458 * DESCRIPTION: Create the association between the handler and the region 459 * this is a two way association. 460 * 461 ******************************************************************************/ 462 463 acpi_status 464 acpi_ev_attach_region(union acpi_operand_object *handler_obj, 465 union acpi_operand_object *region_obj, 466 u8 acpi_ns_is_locked) 467 { 468 469 ACPI_FUNCTION_TRACE(ev_attach_region); 470 471 ACPI_DEBUG_PRINT((ACPI_DB_OPREGION, 472 "Adding Region [%4.4s] %p to address handler %p [%s]\n", 473 acpi_ut_get_node_name(region_obj->region.node), 474 region_obj, handler_obj, 475 acpi_ut_get_region_name(region_obj->region. 476 space_id))); 477 478 /* Link this region to the front of the handler's list */ 479 480 region_obj->region.next = handler_obj->address_space.region_list; 481 handler_obj->address_space.region_list = region_obj; 482 483 /* Install the region's handler */ 484 485 if (region_obj->region.handler) { 486 return_ACPI_STATUS(AE_ALREADY_EXISTS); 487 } 488 489 region_obj->region.handler = handler_obj; 490 acpi_ut_add_reference(handler_obj); 491 492 return_ACPI_STATUS(AE_OK); 493 } 494 495 /******************************************************************************* 496 * 497 * FUNCTION: acpi_ev_execute_reg_method 498 * 499 * PARAMETERS: region_obj - Region object 500 * function - Passed to _REG: On (1) or Off (0) 501 * 502 * RETURN: Status 503 * 504 * DESCRIPTION: Execute _REG method for a region 505 * 506 ******************************************************************************/ 507 508 acpi_status 509 acpi_ev_execute_reg_method(union acpi_operand_object *region_obj, u32 function) 510 { 511 struct acpi_evaluate_info *info; 512 union acpi_operand_object *args[3]; 513 union acpi_operand_object *region_obj2; 514 acpi_status status; 515 516 ACPI_FUNCTION_TRACE(ev_execute_reg_method); 517 518 region_obj2 = acpi_ns_get_secondary_object(region_obj); 519 if (!region_obj2) { 520 return_ACPI_STATUS(AE_NOT_EXIST); 521 } 522 523 if (region_obj2->extra.method_REG == NULL) { 524 return_ACPI_STATUS(AE_OK); 525 } 526 527 /* Allocate and initialize the evaluation information block */ 528 529 info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info)); 530 if (!info) { 531 return_ACPI_STATUS(AE_NO_MEMORY); 532 } 533 534 info->prefix_node = region_obj2->extra.method_REG; 535 info->pathname = NULL; 536 info->parameters = args; 537 info->flags = ACPI_IGNORE_RETURN_VALUE; 538 539 /* 540 * The _REG method has two arguments: 541 * 542 * arg0 - Integer: 543 * Operation region space ID Same value as region_obj->Region.space_id 544 * 545 * arg1 - Integer: 546 * connection status 1 for connecting the handler, 0 for disconnecting 547 * the handler (Passed as a parameter) 548 */ 549 args[0] = 550 acpi_ut_create_integer_object((u64)region_obj->region.space_id); 551 if (!args[0]) { 552 status = AE_NO_MEMORY; 553 goto cleanup1; 554 } 555 556 args[1] = acpi_ut_create_integer_object((u64)function); 557 if (!args[1]) { 558 status = AE_NO_MEMORY; 559 goto cleanup2; 560 } 561 562 args[2] = NULL; /* Terminate list */ 563 564 /* Execute the method, no return value */ 565 566 ACPI_DEBUG_EXEC(acpi_ut_display_init_pathname 567 (ACPI_TYPE_METHOD, info->prefix_node, NULL)); 568 569 status = acpi_ns_evaluate(info); 570 acpi_ut_remove_reference(args[1]); 571 572 cleanup2: 573 acpi_ut_remove_reference(args[0]); 574 575 cleanup1: 576 ACPI_FREE(info); 577 return_ACPI_STATUS(status); 578 } 579 580 /******************************************************************************* 581 * 582 * FUNCTION: acpi_ev_execute_reg_methods 583 * 584 * PARAMETERS: node - Namespace node for the device 585 * space_id - The address space ID 586 * 587 * RETURN: Status 588 * 589 * DESCRIPTION: Run all _REG methods for the input Space ID; 590 * Note: assumes namespace is locked, or system init time. 591 * 592 ******************************************************************************/ 593 594 acpi_status 595 acpi_ev_execute_reg_methods(struct acpi_namespace_node *node, 596 acpi_adr_space_type space_id) 597 { 598 acpi_status status; 599 600 ACPI_FUNCTION_TRACE(ev_execute_reg_methods); 601 602 /* 603 * Run all _REG methods for all Operation Regions for this space ID. This 604 * is a separate walk in order to handle any interdependencies between 605 * regions and _REG methods. (i.e. handlers must be installed for all 606 * regions of this Space ID before we can run any _REG methods) 607 */ 608 status = acpi_ns_walk_namespace(ACPI_TYPE_ANY, node, ACPI_UINT32_MAX, 609 ACPI_NS_WALK_UNLOCK, acpi_ev_reg_run, 610 NULL, &space_id, NULL); 611 612 /* Special case for EC: handle "orphan" _REG methods with no region */ 613 614 if (space_id == ACPI_ADR_SPACE_EC) { 615 acpi_ev_orphan_ec_reg_method(); 616 } 617 618 return_ACPI_STATUS(status); 619 } 620 621 /******************************************************************************* 622 * 623 * FUNCTION: acpi_ev_reg_run 624 * 625 * PARAMETERS: walk_namespace callback 626 * 627 * DESCRIPTION: Run _REG method for region objects of the requested spaceID 628 * 629 ******************************************************************************/ 630 631 static acpi_status 632 acpi_ev_reg_run(acpi_handle obj_handle, 633 u32 level, void *context, void **return_value) 634 { 635 union acpi_operand_object *obj_desc; 636 struct acpi_namespace_node *node; 637 acpi_adr_space_type space_id; 638 acpi_status status; 639 640 space_id = *ACPI_CAST_PTR(acpi_adr_space_type, context); 641 642 /* Convert and validate the device handle */ 643 644 node = acpi_ns_validate_handle(obj_handle); 645 if (!node) { 646 return (AE_BAD_PARAMETER); 647 } 648 649 /* 650 * We only care about regions.and objects that are allowed to have address 651 * space handlers 652 */ 653 if ((node->type != ACPI_TYPE_REGION) && (node != acpi_gbl_root_node)) { 654 return (AE_OK); 655 } 656 657 /* Check for an existing internal object */ 658 659 obj_desc = acpi_ns_get_attached_object(node); 660 if (!obj_desc) { 661 662 /* No object, just exit */ 663 664 return (AE_OK); 665 } 666 667 /* Object is a Region */ 668 669 if (obj_desc->region.space_id != space_id) { 670 671 /* This region is for a different address space, just ignore it */ 672 673 return (AE_OK); 674 } 675 676 status = acpi_ev_execute_reg_method(obj_desc, ACPI_REG_CONNECT); 677 return (status); 678 } 679 680 /******************************************************************************* 681 * 682 * FUNCTION: acpi_ev_orphan_ec_reg_method 683 * 684 * PARAMETERS: None 685 * 686 * RETURN: None 687 * 688 * DESCRIPTION: Execute an "orphan" _REG method that appears under the EC 689 * device. This is a _REG method that has no corresponding region 690 * within the EC device scope. The orphan _REG method appears to 691 * have been enabled by the description of the ECDT in the ACPI 692 * specification: "The availability of the region space can be 693 * detected by providing a _REG method object underneath the 694 * Embedded Controller device." 695 * 696 * To quickly access the EC device, we use the EC_ID that appears 697 * within the ECDT. Otherwise, we would need to perform a time- 698 * consuming namespace walk, executing _HID methods to find the 699 * EC device. 700 * 701 ******************************************************************************/ 702 703 static void acpi_ev_orphan_ec_reg_method(void) 704 { 705 struct acpi_table_ecdt *table; 706 acpi_status status; 707 struct acpi_object_list args; 708 union acpi_object objects[2]; 709 struct acpi_namespace_node *ec_device_node; 710 struct acpi_namespace_node *reg_method; 711 struct acpi_namespace_node *next_node; 712 713 ACPI_FUNCTION_TRACE(ev_orphan_ec_reg_method); 714 715 /* Get the ECDT (if present in system) */ 716 717 status = acpi_get_table(ACPI_SIG_ECDT, 0, 718 ACPI_CAST_INDIRECT_PTR(struct acpi_table_header, 719 &table)); 720 if (ACPI_FAILURE(status)) { 721 return_VOID; 722 } 723 724 /* We need a valid EC_ID string */ 725 726 if (!(*table->id)) { 727 return_VOID; 728 } 729 730 /* Namespace is currently locked, must release */ 731 732 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE); 733 734 /* Get a handle to the EC device referenced in the ECDT */ 735 736 status = acpi_get_handle(NULL, 737 ACPI_CAST_PTR(char, table->id), 738 ACPI_CAST_PTR(acpi_handle, &ec_device_node)); 739 if (ACPI_FAILURE(status)) { 740 goto exit; 741 } 742 743 /* Get a handle to a _REG method immediately under the EC device */ 744 745 status = acpi_get_handle(ec_device_node, 746 METHOD_NAME__REG, ACPI_CAST_PTR(acpi_handle, 747 ®_method)); 748 if (ACPI_FAILURE(status)) { 749 goto exit; 750 } 751 752 /* 753 * Execute the _REG method only if there is no Operation Region in 754 * this scope with the Embedded Controller space ID. Otherwise, it 755 * will already have been executed. Note, this allows for Regions 756 * with other space IDs to be present; but the code below will then 757 * execute the _REG method with the EC space ID argument. 758 */ 759 next_node = acpi_ns_get_next_node(ec_device_node, NULL); 760 while (next_node) { 761 if ((next_node->type == ACPI_TYPE_REGION) && 762 (next_node->object) && 763 (next_node->object->region.space_id == ACPI_ADR_SPACE_EC)) { 764 goto exit; /* Do not execute _REG */ 765 } 766 next_node = acpi_ns_get_next_node(ec_device_node, next_node); 767 } 768 769 /* Evaluate the _REG(EC,Connect) method */ 770 771 args.count = 2; 772 args.pointer = objects; 773 objects[0].type = ACPI_TYPE_INTEGER; 774 objects[0].integer.value = ACPI_ADR_SPACE_EC; 775 objects[1].type = ACPI_TYPE_INTEGER; 776 objects[1].integer.value = ACPI_REG_CONNECT; 777 778 status = acpi_evaluate_object(reg_method, NULL, &args, NULL); 779 780 exit: 781 /* We ignore all errors from above, don't care */ 782 783 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE); 784 return_VOID; 785 } 786