drivers/acpi/events/evxface.c

   1 /******************************************************************************
   2  *
   3  * Module Name: evxface - External interfaces for ACPI events
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2008, 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 <acpi/acnamesp.h>
  46 #include <acpi/acevents.h>
  47 #include <acpi/acinterp.h>
  48
  49 #define _COMPONENT          ACPI_EVENTS
  50 ACPI_MODULE_NAME("evxface")
  51
  52 /*******************************************************************************
  53  *
  54  * FUNCTION:    acpi_install_exception_handler
  55  *
  56  * PARAMETERS:  Handler         - Pointer to the handler function for the
  57  *                                event
  58  *
  59  * RETURN:      Status
  60  *
  61  * DESCRIPTION: Saves the pointer to the handler function
  62  *
  63  ******************************************************************************/
  64 #ifdef ACPI_FUTURE_USAGE
  65 acpi_status acpi_install_exception_handler(acpi_exception_handler handler)
  66 {
  67         acpi_status status;
  68
  69         ACPI_FUNCTION_TRACE(acpi_install_exception_handler);
  70
  71         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
  72         if (ACPI_FAILURE(status)) {
  73                 return_ACPI_STATUS(status);
  74         }
  75
  76         /* Don't allow two handlers. */
  77
  78         if (acpi_gbl_exception_handler) {
  79                 status = AE_ALREADY_EXISTS;
  80                 goto cleanup;
  81         }
  82
  83         /* Install the handler */
  84
  85         acpi_gbl_exception_handler = handler;
  86
  87       cleanup:
  88         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
  89         return_ACPI_STATUS(status);
  90 }
  91
  92 ACPI_EXPORT_SYMBOL(acpi_install_exception_handler)
  93 #endif                          /*  ACPI_FUTURE_USAGE  */
  94 /*******************************************************************************
  95  *
  96  * FUNCTION:    acpi_install_fixed_event_handler
  97  *
  98  * PARAMETERS:  Event           - Event type to enable.
  99  *              Handler         - Pointer to the handler function for the
 100  *                                event
 101  *              Context         - Value passed to the handler on each GPE
 102  *
 103  * RETURN:      Status
 104  *
 105  * DESCRIPTION: Saves the pointer to the handler function and then enables the
 106  *              event.
 107  *
 108  ******************************************************************************/
 109 acpi_status
 110 acpi_install_fixed_event_handler(u32 event,
 111                                  acpi_event_handler handler, void *context)
 112 {
 113         acpi_status status;
 114
 115         ACPI_FUNCTION_TRACE(acpi_install_fixed_event_handler);
 116
 117         /* Parameter validation */
 118
 119         if (event > ACPI_EVENT_MAX) {
 120                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 121         }
 122
 123         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 124         if (ACPI_FAILURE(status)) {
 125                 return_ACPI_STATUS(status);
 126         }
 127
 128         /* Don't allow two handlers. */
 129
 130         if (NULL != acpi_gbl_fixed_event_handlers[event].handler) {
 131                 status = AE_ALREADY_EXISTS;
 132                 goto cleanup;
 133         }
 134
 135         /* Install the handler before enabling the event */
 136
 137         acpi_gbl_fixed_event_handlers[event].handler = handler;
 138         acpi_gbl_fixed_event_handlers[event].context = context;
 139
 140         status = acpi_clear_event(event);
 141         if (ACPI_SUCCESS(status))
 142                 status = acpi_enable_event(event, 0);
 143         if (ACPI_FAILURE(status)) {
 144                 ACPI_WARNING((AE_INFO, "Could not enable fixed event %X",
 145                               event));
 146
 147                 /* Remove the handler */
 148
 149                 acpi_gbl_fixed_event_handlers[event].handler = NULL;
 150                 acpi_gbl_fixed_event_handlers[event].context = NULL;
 151         } else {
 152                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 153                                   "Enabled fixed event %X, Handler=%p\n", event,
 154                                   handler));
 155         }
 156
 157       cleanup:
 158         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 159         return_ACPI_STATUS(status);
 160 }
 161
 162 ACPI_EXPORT_SYMBOL(acpi_install_fixed_event_handler)
 163
 164 /*******************************************************************************
 165  *
 166  * FUNCTION:    acpi_remove_fixed_event_handler
 167  *
 168  * PARAMETERS:  Event           - Event type to disable.
 169  *              Handler         - Address of the handler
 170  *
 171  * RETURN:      Status
 172  *
 173  * DESCRIPTION: Disables the event and unregisters the event handler.
 174  *
 175  ******************************************************************************/
 176 acpi_status
 177 acpi_remove_fixed_event_handler(u32 event, acpi_event_handler handler)
 178 {
 179         acpi_status status = AE_OK;
 180
 181         ACPI_FUNCTION_TRACE(acpi_remove_fixed_event_handler);
 182
 183         /* Parameter validation */
 184
 185         if (event > ACPI_EVENT_MAX) {
 186                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 187         }
 188
 189         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 190         if (ACPI_FAILURE(status)) {
 191                 return_ACPI_STATUS(status);
 192         }
 193
 194         /* Disable the event before removing the handler */
 195
 196         status = acpi_disable_event(event, 0);
 197
 198         /* Always Remove the handler */
 199
 200         acpi_gbl_fixed_event_handlers[event].handler = NULL;
 201         acpi_gbl_fixed_event_handlers[event].context = NULL;
 202
 203         if (ACPI_FAILURE(status)) {
 204                 ACPI_WARNING((AE_INFO,
 205                               "Could not write to fixed event enable register %X",
 206                               event));
 207         } else {
 208                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Disabled fixed event %X\n",
 209                                   event));
 210         }
 211
 212         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 213         return_ACPI_STATUS(status);
 214 }
 215
 216 ACPI_EXPORT_SYMBOL(acpi_remove_fixed_event_handler)
 217
 218 /*******************************************************************************
 219  *
 220  * FUNCTION:    acpi_install_notify_handler
 221  *
 222  * PARAMETERS:  Device          - The device for which notifies will be handled
 223  *              handler_type    - The type of handler:
 224  *                                  ACPI_SYSTEM_NOTIFY: system_handler (00-7f)
 225  *                                  ACPI_DEVICE_NOTIFY: driver_handler (80-ff)
 226  *                                  ACPI_ALL_NOTIFY:  both system and device
 227  *              Handler         - Address of the handler
 228  *              Context         - Value passed to the handler on each GPE
 229  *
 230  * RETURN:      Status
 231  *
 232  * DESCRIPTION: Install a handler for notifies on an ACPI device
 233  *
 234  ******************************************************************************/
 235 acpi_status
 236 acpi_install_notify_handler(acpi_handle device,
 237                             u32 handler_type,
 238                             acpi_notify_handler handler, void *context)
 239 {
 240         union acpi_operand_object *obj_desc;
 241         union acpi_operand_object *notify_obj;
 242         struct acpi_namespace_node *node;
 243         acpi_status status;
 244
 245         ACPI_FUNCTION_TRACE(acpi_install_notify_handler);
 246
 247         /* Parameter validation */
 248
 249         if ((!device) ||
 250             (!handler) || (handler_type > ACPI_MAX_NOTIFY_HANDLER_TYPE)) {
 251                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 252         }
 253
 254         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 255         if (ACPI_FAILURE(status)) {
 256                 return_ACPI_STATUS(status);
 257         }
 258
 259         /* Convert and validate the device handle */
 260
 261         node = acpi_ns_map_handle_to_node(device);
 262         if (!node) {
 263                 status = AE_BAD_PARAMETER;
 264                 goto unlock_and_exit;
 265         }
 266
 267         /*
 268          * Root Object:
 269          * Registering a notify handler on the root object indicates that the
 270          * caller wishes to receive notifications for all objects.  Note that
 271          * only one <external> global handler can be regsitered (per notify type).
 272          */
 273         if (device == ACPI_ROOT_OBJECT) {
 274
 275                 /* Make sure the handler is not already installed */
 276
 277                 if (((handler_type & ACPI_SYSTEM_NOTIFY) &&
 278                      acpi_gbl_system_notify.handler) ||
 279                     ((handler_type & ACPI_DEVICE_NOTIFY) &&
 280                      acpi_gbl_device_notify.handler)) {
 281                         status = AE_ALREADY_EXISTS;
 282                         goto unlock_and_exit;
 283                 }
 284
 285                 if (handler_type & ACPI_SYSTEM_NOTIFY) {
 286                         acpi_gbl_system_notify.node = node;
 287                         acpi_gbl_system_notify.handler = handler;
 288                         acpi_gbl_system_notify.context = context;
 289                 }
 290
 291                 if (handler_type & ACPI_DEVICE_NOTIFY) {
 292                         acpi_gbl_device_notify.node = node;
 293                         acpi_gbl_device_notify.handler = handler;
 294                         acpi_gbl_device_notify.context = context;
 295                 }
 296
 297                 /* Global notify handler installed */
 298         }
 299
 300         /*
 301          * All Other Objects:
 302          * Caller will only receive notifications specific to the target object.
 303          * Note that only certain object types can receive notifications.
 304          */
 305         else {
 306                 /* Notifies allowed on this object? */
 307
 308                 if (!acpi_ev_is_notify_object(node)) {
 309                         status = AE_TYPE;
 310                         goto unlock_and_exit;
 311                 }
 312
 313                 /* Check for an existing internal object */
 314
 315                 obj_desc = acpi_ns_get_attached_object(node);
 316                 if (obj_desc) {
 317
 318                         /* Object exists - make sure there's no handler */
 319
 320                         if (((handler_type & ACPI_SYSTEM_NOTIFY) &&
 321                              obj_desc->common_notify.system_notify) ||
 322                             ((handler_type & ACPI_DEVICE_NOTIFY) &&
 323                              obj_desc->common_notify.device_notify)) {
 324                                 status = AE_ALREADY_EXISTS;
 325                                 goto unlock_and_exit;
 326                         }
 327                 } else {
 328                         /* Create a new object */
 329
 330                         obj_desc = acpi_ut_create_internal_object(node->type);
 331                         if (!obj_desc) {
 332                                 status = AE_NO_MEMORY;
 333                                 goto unlock_and_exit;
 334                         }
 335
 336                         /* Attach new object to the Node */
 337
 338                         status =
 339                             acpi_ns_attach_object(device, obj_desc, node->type);
 340
 341                         /* Remove local reference to the object */
 342
 343                         acpi_ut_remove_reference(obj_desc);
 344                         if (ACPI_FAILURE(status)) {
 345                                 goto unlock_and_exit;
 346                         }
 347                 }
 348
 349                 /* Install the handler */
 350
 351                 notify_obj =
 352                     acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_NOTIFY);
 353                 if (!notify_obj) {
 354                         status = AE_NO_MEMORY;
 355                         goto unlock_and_exit;
 356                 }
 357
 358                 notify_obj->notify.node = node;
 359                 notify_obj->notify.handler = handler;
 360                 notify_obj->notify.context = context;
 361
 362                 if (handler_type & ACPI_SYSTEM_NOTIFY) {
 363                         obj_desc->common_notify.system_notify = notify_obj;
 364                 }
 365
 366                 if (handler_type & ACPI_DEVICE_NOTIFY) {
 367                         obj_desc->common_notify.device_notify = notify_obj;
 368                 }
 369
 370                 if (handler_type == ACPI_ALL_NOTIFY) {
 371
 372                         /* Extra ref if installed in both */
 373
 374                         acpi_ut_add_reference(notify_obj);
 375                 }
 376         }
 377
 378       unlock_and_exit:
 379         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 380         return_ACPI_STATUS(status);
 381 }
 382
 383 ACPI_EXPORT_SYMBOL(acpi_install_notify_handler)
 384
 385 /*******************************************************************************
 386  *
 387  * FUNCTION:    acpi_remove_notify_handler
 388  *
 389  * PARAMETERS:  Device          - The device for which notifies will be handled
 390  *              handler_type    - The type of handler:
 391  *                                  ACPI_SYSTEM_NOTIFY: system_handler (00-7f)
 392  *                                  ACPI_DEVICE_NOTIFY: driver_handler (80-ff)
 393  *                                  ACPI_ALL_NOTIFY:  both system and device
 394  *              Handler         - Address of the handler
 395  *
 396  * RETURN:      Status
 397  *
 398  * DESCRIPTION: Remove a handler for notifies on an ACPI device
 399  *
 400  ******************************************************************************/
 401 acpi_status
 402 acpi_remove_notify_handler(acpi_handle device,
 403                            u32 handler_type, acpi_notify_handler handler)
 404 {
 405         union acpi_operand_object *notify_obj;
 406         union acpi_operand_object *obj_desc;
 407         struct acpi_namespace_node *node;
 408         acpi_status status;
 409
 410         ACPI_FUNCTION_TRACE(acpi_remove_notify_handler);
 411
 412         /* Parameter validation */
 413
 414         if ((!device) ||
 415             (!handler) || (handler_type > ACPI_MAX_NOTIFY_HANDLER_TYPE)) {
 416                 status = AE_BAD_PARAMETER;
 417                 goto exit;
 418         }
 419
 420         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 421         if (ACPI_FAILURE(status)) {
 422                 goto exit;
 423         }
 424
 425         /* Convert and validate the device handle */
 426
 427         node = acpi_ns_map_handle_to_node(device);
 428         if (!node) {
 429                 status = AE_BAD_PARAMETER;
 430                 goto unlock_and_exit;
 431         }
 432
 433         /* Root Object */
 434
 435         if (device == ACPI_ROOT_OBJECT) {
 436                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 437                                   "Removing notify handler for namespace root object\n"));
 438
 439                 if (((handler_type & ACPI_SYSTEM_NOTIFY) &&
 440                      !acpi_gbl_system_notify.handler) ||
 441                     ((handler_type & ACPI_DEVICE_NOTIFY) &&
 442                      !acpi_gbl_device_notify.handler)) {
 443                         status = AE_NOT_EXIST;
 444                         goto unlock_and_exit;
 445                 }
 446
 447                 /* Make sure all deferred tasks are completed */
 448
 449                 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 450                 acpi_os_wait_events_complete(NULL);
 451                 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 452                 if (ACPI_FAILURE(status)) {
 453                         goto exit;
 454                 }
 455
 456                 if (handler_type & ACPI_SYSTEM_NOTIFY) {
 457                         acpi_gbl_system_notify.node = NULL;
 458                         acpi_gbl_system_notify.handler = NULL;
 459                         acpi_gbl_system_notify.context = NULL;
 460                 }
 461
 462                 if (handler_type & ACPI_DEVICE_NOTIFY) {
 463                         acpi_gbl_device_notify.node = NULL;
 464                         acpi_gbl_device_notify.handler = NULL;
 465                         acpi_gbl_device_notify.context = NULL;
 466                 }
 467         }
 468
 469         /* All Other Objects */
 470
 471         else {
 472                 /* Notifies allowed on this object? */
 473
 474                 if (!acpi_ev_is_notify_object(node)) {
 475                         status = AE_TYPE;
 476                         goto unlock_and_exit;
 477                 }
 478
 479                 /* Check for an existing internal object */
 480
 481                 obj_desc = acpi_ns_get_attached_object(node);
 482                 if (!obj_desc) {
 483                         status = AE_NOT_EXIST;
 484                         goto unlock_and_exit;
 485                 }
 486
 487                 /* Object exists - make sure there's an existing handler */
 488
 489                 if (handler_type & ACPI_SYSTEM_NOTIFY) {
 490                         notify_obj = obj_desc->common_notify.system_notify;
 491                         if (!notify_obj) {
 492                                 status = AE_NOT_EXIST;
 493                                 goto unlock_and_exit;
 494                         }
 495
 496                         if (notify_obj->notify.handler != handler) {
 497                                 status = AE_BAD_PARAMETER;
 498                                 goto unlock_and_exit;
 499                         }
 500                         /* Make sure all deferred tasks are completed */
 501
 502                         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 503                         acpi_os_wait_events_complete(NULL);
 504                         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 505                         if (ACPI_FAILURE(status)) {
 506                                 goto exit;
 507                         }
 508
 509                         /* Remove the handler */
 510                         obj_desc->common_notify.system_notify = NULL;
 511                         acpi_ut_remove_reference(notify_obj);
 512                 }
 513
 514                 if (handler_type & ACPI_DEVICE_NOTIFY) {
 515                         notify_obj = obj_desc->common_notify.device_notify;
 516                         if (!notify_obj) {
 517                                 status = AE_NOT_EXIST;
 518                                 goto unlock_and_exit;
 519                         }
 520
 521                         if (notify_obj->notify.handler != handler) {
 522                                 status = AE_BAD_PARAMETER;
 523                                 goto unlock_and_exit;
 524                         }
 525                         /* Make sure all deferred tasks are completed */
 526
 527                         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 528                         acpi_os_wait_events_complete(NULL);
 529                         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 530                         if (ACPI_FAILURE(status)) {
 531                                 goto exit;
 532                         }
 533
 534                         /* Remove the handler */
 535                         obj_desc->common_notify.device_notify = NULL;
 536                         acpi_ut_remove_reference(notify_obj);
 537                 }
 538         }
 539
 540       unlock_and_exit:
 541         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 542       exit:
 543         if (ACPI_FAILURE(status))
 544                 ACPI_EXCEPTION((AE_INFO, status, "Removing notify handler"));
 545         return_ACPI_STATUS(status);
 546 }
 547
 548 ACPI_EXPORT_SYMBOL(acpi_remove_notify_handler)
 549
 550 /*******************************************************************************
 551  *
 552  * FUNCTION:    acpi_install_gpe_handler
 553  *
 554  * PARAMETERS:  gpe_device      - Namespace node for the GPE (NULL for FADT
 555  *                                defined GPEs)
 556  *              gpe_number      - The GPE number within the GPE block
 557  *              Type            - Whether this GPE should be treated as an
 558  *                                edge- or level-triggered interrupt.
 559  *              Address         - Address of the handler
 560  *              Context         - Value passed to the handler on each GPE
 561  *
 562  * RETURN:      Status
 563  *
 564  * DESCRIPTION: Install a handler for a General Purpose Event.
 565  *
 566  ******************************************************************************/
 567 acpi_status
 568 acpi_install_gpe_handler(acpi_handle gpe_device,
 569                          u32 gpe_number,
 570                          u32 type, acpi_event_handler address, void *context)
 571 {
 572         struct acpi_gpe_event_info *gpe_event_info;
 573         struct acpi_handler_info *handler;
 574         acpi_status status;
 575         acpi_cpu_flags flags;
 576
 577         ACPI_FUNCTION_TRACE(acpi_install_gpe_handler);
 578
 579         /* Parameter validation */
 580
 581         if ((!address) || (type > ACPI_GPE_XRUPT_TYPE_MASK)) {
 582                 status = AE_BAD_PARAMETER;
 583                 goto exit;
 584         }
 585
 586         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 587         if (ACPI_FAILURE(status)) {
 588                 goto exit;
 589         }
 590
 591         /* Ensure that we have a valid GPE number */
 592
 593         gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
 594         if (!gpe_event_info) {
 595                 status = AE_BAD_PARAMETER;
 596                 goto unlock_and_exit;
 597         }
 598
 599         /* Make sure that there isn't a handler there already */
 600
 601         if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
 602             ACPI_GPE_DISPATCH_HANDLER) {
 603                 status = AE_ALREADY_EXISTS;
 604                 goto unlock_and_exit;
 605         }
 606
 607         /* Allocate and init handler object */
 608
 609         handler = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_handler_info));
 610         if (!handler) {
 611                 status = AE_NO_MEMORY;
 612                 goto unlock_and_exit;
 613         }
 614
 615         handler->address = address;
 616         handler->context = context;
 617         handler->method_node = gpe_event_info->dispatch.method_node;
 618
 619         /* Disable the GPE before installing the handler */
 620
 621         status = acpi_ev_disable_gpe(gpe_event_info);
 622         if (ACPI_FAILURE(status)) {
 623                 goto unlock_and_exit;
 624         }
 625
 626         /* Install the handler */
 627
 628         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 629         gpe_event_info->dispatch.handler = handler;
 630
 631         /* Setup up dispatch flags to indicate handler (vs. method) */
 632
 633         gpe_event_info->flags &= ~(ACPI_GPE_XRUPT_TYPE_MASK | ACPI_GPE_DISPATCH_MASK);  /* Clear bits */
 634         gpe_event_info->flags |= (u8) (type | ACPI_GPE_DISPATCH_HANDLER);
 635
 636         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 637
 638       unlock_and_exit:
 639         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 640       exit:
 641         if (ACPI_FAILURE(status))
 642                 ACPI_EXCEPTION((AE_INFO, status,
 643                                 "Installing notify handler failed"));
 644         return_ACPI_STATUS(status);
 645 }
 646
 647 ACPI_EXPORT_SYMBOL(acpi_install_gpe_handler)
 648
 649 /*******************************************************************************
 650  *
 651  * FUNCTION:    acpi_remove_gpe_handler
 652  *
 653  * PARAMETERS:  gpe_device      - Namespace node for the GPE (NULL for FADT
 654  *                                defined GPEs)
 655  *              gpe_number      - The event to remove a handler
 656  *              Address         - Address of the handler
 657  *
 658  * RETURN:      Status
 659  *
 660  * DESCRIPTION: Remove a handler for a General Purpose acpi_event.
 661  *
 662  ******************************************************************************/
 663 acpi_status
 664 acpi_remove_gpe_handler(acpi_handle gpe_device,
 665                         u32 gpe_number, acpi_event_handler address)
 666 {
 667         struct acpi_gpe_event_info *gpe_event_info;
 668         struct acpi_handler_info *handler;
 669         acpi_status status;
 670         acpi_cpu_flags flags;
 671
 672         ACPI_FUNCTION_TRACE(acpi_remove_gpe_handler);
 673
 674         /* Parameter validation */
 675
 676         if (!address) {
 677                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 678         }
 679
 680         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 681         if (ACPI_FAILURE(status)) {
 682                 return_ACPI_STATUS(status);
 683         }
 684
 685         /* Ensure that we have a valid GPE number */
 686
 687         gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
 688         if (!gpe_event_info) {
 689                 status = AE_BAD_PARAMETER;
 690                 goto unlock_and_exit;
 691         }
 692
 693         /* Make sure that a handler is indeed installed */
 694
 695         if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) !=
 696             ACPI_GPE_DISPATCH_HANDLER) {
 697                 status = AE_NOT_EXIST;
 698                 goto unlock_and_exit;
 699         }
 700
 701         /* Make sure that the installed handler is the same */
 702
 703         if (gpe_event_info->dispatch.handler->address != address) {
 704                 status = AE_BAD_PARAMETER;
 705                 goto unlock_and_exit;
 706         }
 707
 708         /* Disable the GPE before removing the handler */
 709
 710         status = acpi_ev_disable_gpe(gpe_event_info);
 711         if (ACPI_FAILURE(status)) {
 712                 goto unlock_and_exit;
 713         }
 714
 715         /* Make sure all deferred tasks are completed */
 716
 717         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 718         acpi_os_wait_events_complete(NULL);
 719         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 720         if (ACPI_FAILURE(status)) {
 721                 return_ACPI_STATUS(status);
 722         }
 723
 724         /* Remove the handler */
 725
 726         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 727         handler = gpe_event_info->dispatch.handler;
 728
 729         /* Restore Method node (if any), set dispatch flags */
 730
 731         gpe_event_info->dispatch.method_node = handler->method_node;
 732         gpe_event_info->flags &= ~ACPI_GPE_DISPATCH_MASK;       /* Clear bits */
 733         if (handler->method_node) {
 734                 gpe_event_info->flags |= ACPI_GPE_DISPATCH_METHOD;
 735         }
 736         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 737
 738         /* Now we can free the handler object */
 739
 740         ACPI_FREE(handler);
 741
 742       unlock_and_exit:
 743         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 744         return_ACPI_STATUS(status);
 745 }
 746
 747 ACPI_EXPORT_SYMBOL(acpi_remove_gpe_handler)
 748
 749 /*******************************************************************************
 750  *
 751  * FUNCTION:    acpi_acquire_global_lock
 752  *
 753  * PARAMETERS:  Timeout         - How long the caller is willing to wait
 754  *              Handle          - Where the handle to the lock is returned
 755  *                                (if acquired)
 756  *
 757  * RETURN:      Status
 758  *
 759  * DESCRIPTION: Acquire the ACPI Global Lock
 760  *
 761  * Note: Allows callers with the same thread ID to acquire the global lock
 762  * multiple times. In other words, externally, the behavior of the global lock
 763  * is identical to an AML mutex. On the first acquire, a new handle is
 764  * returned. On any subsequent calls to acquire by the same thread, the same
 765  * handle is returned.
 766  *
 767  ******************************************************************************/
 768 acpi_status acpi_acquire_global_lock(u16 timeout, u32 * handle)
 769 {
 770         acpi_status status;
 771
 772         if (!handle) {
 773                 return (AE_BAD_PARAMETER);
 774         }
 775
 776         /* Must lock interpreter to prevent race conditions */
 777
 778         acpi_ex_enter_interpreter();
 779
 780         status = acpi_ex_acquire_mutex_object(timeout,
 781                                               acpi_gbl_global_lock_mutex,
 782                                               acpi_os_get_thread_id());
 783
 784         if (ACPI_SUCCESS(status)) {
 785
 786                 /* Return the global lock handle (updated in acpi_ev_acquire_global_lock) */
 787
 788                 *handle = acpi_gbl_global_lock_handle;
 789         }
 790
 791         acpi_ex_exit_interpreter();
 792         return (status);
 793 }
 794
 795 ACPI_EXPORT_SYMBOL(acpi_acquire_global_lock)
 796
 797 /*******************************************************************************
 798  *
 799  * FUNCTION:    acpi_release_global_lock
 800  *
 801  * PARAMETERS:  Handle      - Returned from acpi_acquire_global_lock
 802  *
 803  * RETURN:      Status
 804  *
 805  * DESCRIPTION: Release the ACPI Global Lock. The handle must be valid.
 806  *
 807  ******************************************************************************/
 808 acpi_status acpi_release_global_lock(u32 handle)
 809 {
 810         acpi_status status;
 811
 812         if (!handle || (handle != acpi_gbl_global_lock_handle)) {
 813                 return (AE_NOT_ACQUIRED);
 814         }
 815
 816         status = acpi_ex_release_mutex_object(acpi_gbl_global_lock_mutex);
 817         return (status);
 818 }
 819
 820 ACPI_EXPORT_SYMBOL(acpi_release_global_lock)