git.oblomov.eu Git - linux-2.6/blob - drivers/acpi/events/evxface.c

   1 /******************************************************************************
   2  *
   3  * Module Name: evxface - External interfaces for ACPI events
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2006, R. Byron Moore
   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  *
  97  * FUNCTION:    acpi_install_fixed_event_handler
  98  *
  99  * PARAMETERS:  Event           - Event type to enable.
 100  *              Handler         - Pointer to the handler function for the
 101  *                                event
 102  *              Context         - Value passed to the handler on each GPE
 103  *
 104  * RETURN:      Status
 105  *
 106  * DESCRIPTION: Saves the pointer to the handler function and then enables the
 107  *              event.
 108  *
 109  ******************************************************************************/
 110 acpi_status
 111 acpi_install_fixed_event_handler(u32 event,
 112                                  acpi_event_handler handler, void *context)
 113 {
 114         acpi_status status;
 115
 116         ACPI_FUNCTION_TRACE(acpi_install_fixed_event_handler);
 117
 118         /* Parameter validation */
 119
 120         if (event > ACPI_EVENT_MAX) {
 121                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 122         }
 123
 124         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 125         if (ACPI_FAILURE(status)) {
 126                 return_ACPI_STATUS(status);
 127         }
 128
 129         /* Don't allow two handlers. */
 130
 131         if (NULL != acpi_gbl_fixed_event_handlers[event].handler) {
 132                 status = AE_ALREADY_EXISTS;
 133                 goto cleanup;
 134         }
 135
 136         /* Install the handler before enabling the event */
 137
 138         acpi_gbl_fixed_event_handlers[event].handler = handler;
 139         acpi_gbl_fixed_event_handlers[event].context = context;
 140
 141         status = acpi_clear_event(event);
 142         if (ACPI_SUCCESS(status))
 143                 status = acpi_enable_event(event, 0);
 144         if (ACPI_FAILURE(status)) {
 145                 ACPI_WARNING((AE_INFO, "Could not enable fixed event %X",
 146                               event));
 147
 148                 /* Remove the handler */
 149
 150                 acpi_gbl_fixed_event_handlers[event].handler = NULL;
 151                 acpi_gbl_fixed_event_handlers[event].context = NULL;
 152         } else {
 153                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 154                                   "Enabled fixed event %X, Handler=%p\n", event,
 155                                   handler));
 156         }
 157
 158       cleanup:
 159         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 160         return_ACPI_STATUS(status);
 161 }
 162
 163 ACPI_EXPORT_SYMBOL(acpi_install_fixed_event_handler)
 164
 165 /*******************************************************************************
 166  *
 167  * FUNCTION:    acpi_remove_fixed_event_handler
 168  *
 169  * PARAMETERS:  Event           - Event type to disable.
 170  *              Handler         - Address of the handler
 171  *
 172  * RETURN:      Status
 173  *
 174  * DESCRIPTION: Disables the event and unregisters the event handler.
 175  *
 176  ******************************************************************************/
 177 acpi_status
 178 acpi_remove_fixed_event_handler(u32 event, acpi_event_handler handler)
 179 {
 180         acpi_status status = AE_OK;
 181
 182         ACPI_FUNCTION_TRACE(acpi_remove_fixed_event_handler);
 183
 184         /* Parameter validation */
 185
 186         if (event > ACPI_EVENT_MAX) {
 187                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 188         }
 189
 190         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 191         if (ACPI_FAILURE(status)) {
 192                 return_ACPI_STATUS(status);
 193         }
 194
 195         /* Disable the event before removing the handler */
 196
 197         status = acpi_disable_event(event, 0);
 198
 199         /* Always Remove the handler */
 200
 201         acpi_gbl_fixed_event_handlers[event].handler = NULL;
 202         acpi_gbl_fixed_event_handlers[event].context = NULL;
 203
 204         if (ACPI_FAILURE(status)) {
 205                 ACPI_WARNING((AE_INFO,
 206                               "Could not write to fixed event enable register %X",
 207                               event));
 208         } else {
 209                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Disabled fixed event %X\n",
 210                                   event));
 211         }
 212
 213         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 214         return_ACPI_STATUS(status);
 215 }
 216
 217 ACPI_EXPORT_SYMBOL(acpi_remove_fixed_event_handler)
 218
 219 /*******************************************************************************
 220  *
 221  * FUNCTION:    acpi_install_notify_handler
 222  *
 223  * PARAMETERS:  Device          - The device for which notifies will be handled
 224  *              handler_type    - The type of handler:
 225  *                                  ACPI_SYSTEM_NOTIFY: system_handler (00-7f)
 226  *                                  ACPI_DEVICE_NOTIFY: driver_handler (80-ff)
 227  *                                  ACPI_ALL_NOTIFY:  both system and device
 228  *              Handler         - Address of the handler
 229  *              Context         - Value passed to the handler on each GPE
 230  *
 231  * RETURN:      Status
 232  *
 233  * DESCRIPTION: Install a handler for notifies on an ACPI device
 234  *
 235  ******************************************************************************/
 236 acpi_status
 237 acpi_install_notify_handler(acpi_handle device,
 238                             u32 handler_type,
 239                             acpi_notify_handler handler, void *context)
 240 {
 241         union acpi_operand_object *obj_desc;
 242         union acpi_operand_object *notify_obj;
 243         struct acpi_namespace_node *node;
 244         acpi_status status;
 245
 246         ACPI_FUNCTION_TRACE(acpi_install_notify_handler);
 247
 248         /* Parameter validation */
 249
 250         if ((!device) ||
 251             (!handler) || (handler_type > ACPI_MAX_NOTIFY_HANDLER_TYPE)) {
 252                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 253         }
 254
 255         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 256         if (ACPI_FAILURE(status)) {
 257                 return_ACPI_STATUS(status);
 258         }
 259
 260         /* Convert and validate the device handle */
 261
 262         node = acpi_ns_map_handle_to_node(device);
 263         if (!node) {
 264                 status = AE_BAD_PARAMETER;
 265                 goto unlock_and_exit;
 266         }
 267
 268         /*
 269          * Root Object:
 270          * Registering a notify handler on the root object indicates that the
 271          * caller wishes to receive notifications for all objects.  Note that
 272          * only one <external> global handler can be regsitered (per notify type).
 273          */
 274         if (device == ACPI_ROOT_OBJECT) {
 275
 276                 /* Make sure the handler is not already installed */
 277
 278                 if (((handler_type & ACPI_SYSTEM_NOTIFY) &&
 279                      acpi_gbl_system_notify.handler) ||
 280                     ((handler_type & ACPI_DEVICE_NOTIFY) &&
 281                      acpi_gbl_device_notify.handler)) {
 282                         status = AE_ALREADY_EXISTS;
 283                         goto unlock_and_exit;
 284                 }
 285
 286                 if (handler_type & ACPI_SYSTEM_NOTIFY) {
 287                         acpi_gbl_system_notify.node = node;
 288                         acpi_gbl_system_notify.handler = handler;
 289                         acpi_gbl_system_notify.context = context;
 290                 }
 291
 292                 if (handler_type & ACPI_DEVICE_NOTIFY) {
 293                         acpi_gbl_device_notify.node = node;
 294                         acpi_gbl_device_notify.handler = handler;
 295                         acpi_gbl_device_notify.context = context;
 296                 }
 297
 298                 /* Global notify handler installed */
 299         }
 300
 301         /*
 302          * All Other Objects:
 303          * Caller will only receive notifications specific to the target object.
 304          * Note that only certain object types can receive notifications.
 305          */
 306         else {
 307                 /* Notifies allowed on this object? */
 308
 309                 if (!acpi_ev_is_notify_object(node)) {
 310                         status = AE_TYPE;
 311                         goto unlock_and_exit;
 312                 }
 313
 314                 /* Check for an existing internal object */
 315
 316                 obj_desc = acpi_ns_get_attached_object(node);
 317                 if (obj_desc) {
 318
 319                         /* Object exists - make sure there's no handler */
 320
 321                         if (((handler_type & ACPI_SYSTEM_NOTIFY) &&
 322                              obj_desc->common_notify.system_notify) ||
 323                             ((handler_type & ACPI_DEVICE_NOTIFY) &&
 324                              obj_desc->common_notify.device_notify)) {
 325                                 status = AE_ALREADY_EXISTS;
 326                                 goto unlock_and_exit;
 327                         }
 328                 } else {
 329                         /* Create a new object */
 330
 331                         obj_desc = acpi_ut_create_internal_object(node->type);
 332                         if (!obj_desc) {
 333                                 status = AE_NO_MEMORY;
 334                                 goto unlock_and_exit;
 335                         }
 336
 337                         /* Attach new object to the Node */
 338
 339                         status =
 340                             acpi_ns_attach_object(device, obj_desc, node->type);
 341
 342                         /* Remove local reference to the object */
 343
 344                         acpi_ut_remove_reference(obj_desc);
 345                         if (ACPI_FAILURE(status)) {
 346                                 goto unlock_and_exit;
 347                         }
 348                 }
 349
 350                 /* Install the handler */
 351
 352                 notify_obj =
 353                     acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_NOTIFY);
 354                 if (!notify_obj) {
 355                         status = AE_NO_MEMORY;
 356                         goto unlock_and_exit;
 357                 }
 358
 359                 notify_obj->notify.node = node;
 360                 notify_obj->notify.handler = handler;
 361                 notify_obj->notify.context = context;
 362
 363                 if (handler_type & ACPI_SYSTEM_NOTIFY) {
 364                         obj_desc->common_notify.system_notify = notify_obj;
 365                 }
 366
 367                 if (handler_type & ACPI_DEVICE_NOTIFY) {
 368                         obj_desc->common_notify.device_notify = notify_obj;
 369                 }
 370
 371                 if (handler_type == ACPI_ALL_NOTIFY) {
 372
 373                         /* Extra ref if installed in both */
 374
 375                         acpi_ut_add_reference(notify_obj);
 376                 }
 377         }
 378
 379       unlock_and_exit:
 380         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 381         return_ACPI_STATUS(status);
 382 }
 383
 384 ACPI_EXPORT_SYMBOL(acpi_install_notify_handler)
 385
 386 /*******************************************************************************
 387  *
 388  * FUNCTION:    acpi_remove_notify_handler
 389  *
 390  * PARAMETERS:  Device          - The device for which notifies will be handled
 391  *              handler_type    - The type of handler:
 392  *                                  ACPI_SYSTEM_NOTIFY: system_handler (00-7f)
 393  *                                  ACPI_DEVICE_NOTIFY: driver_handler (80-ff)
 394  *                                  ACPI_ALL_NOTIFY:  both system and device
 395  *              Handler         - Address of the handler
 396  *
 397  * RETURN:      Status
 398  *
 399  * DESCRIPTION: Remove a handler for notifies on an ACPI device
 400  *
 401  ******************************************************************************/
 402 acpi_status
 403 acpi_remove_notify_handler(acpi_handle device,
 404                            u32 handler_type, acpi_notify_handler handler)
 405 {
 406         union acpi_operand_object *notify_obj;
 407         union acpi_operand_object *obj_desc;
 408         struct acpi_namespace_node *node;
 409         acpi_status status;
 410
 411         ACPI_FUNCTION_TRACE(acpi_remove_notify_handler);
 412
 413         /* Parameter validation */
 414
 415         if ((!device) ||
 416             (!handler) || (handler_type > ACPI_MAX_NOTIFY_HANDLER_TYPE)) {
 417                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 418         }
 419
 420         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 421         if (ACPI_FAILURE(status)) {
 422                 return_ACPI_STATUS(status);
 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                         return_ACPI_STATUS(status);
 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                             (notify_obj->notify.handler != handler)) {
 493                                 status = AE_BAD_PARAMETER;
 494                                 goto unlock_and_exit;
 495                         }
 496                         /* Make sure all deferred tasks are completed */
 497
 498                         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 499                         acpi_os_wait_events_complete(NULL);
 500                         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 501                         if (ACPI_FAILURE(status)) {
 502                                 return_ACPI_STATUS(status);
 503                         }
 504
 505                         /* Remove the handler */
 506                         obj_desc->common_notify.system_notify = NULL;
 507                         acpi_ut_remove_reference(notify_obj);
 508                 }
 509
 510                 if (handler_type & ACPI_DEVICE_NOTIFY) {
 511                         notify_obj = obj_desc->common_notify.device_notify;
 512                         if ((!notify_obj) ||
 513                             (notify_obj->notify.handler != handler)) {
 514                                 status = AE_BAD_PARAMETER;
 515                                 goto unlock_and_exit;
 516                         }
 517                         /* Make sure all deferred tasks are completed */
 518
 519                         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 520                         acpi_os_wait_events_complete(NULL);
 521                         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 522                         if (ACPI_FAILURE(status)) {
 523                                 return_ACPI_STATUS(status);
 524                         }
 525
 526                         /* Remove the handler */
 527                         obj_desc->common_notify.device_notify = NULL;
 528                         acpi_ut_remove_reference(notify_obj);
 529                 }
 530         }
 531
 532       unlock_and_exit:
 533         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 534         return_ACPI_STATUS(status);
 535 }
 536
 537 ACPI_EXPORT_SYMBOL(acpi_remove_notify_handler)
 538
 539 /*******************************************************************************
 540  *
 541  * FUNCTION:    acpi_install_gpe_handler
 542  *
 543  * PARAMETERS:  gpe_device      - Namespace node for the GPE (NULL for FADT
 544  *                                defined GPEs)
 545  *              gpe_number      - The GPE number within the GPE block
 546  *              Type            - Whether this GPE should be treated as an
 547  *                                edge- or level-triggered interrupt.
 548  *              Address         - Address of the handler
 549  *              Context         - Value passed to the handler on each GPE
 550  *
 551  * RETURN:      Status
 552  *
 553  * DESCRIPTION: Install a handler for a General Purpose Event.
 554  *
 555  ******************************************************************************/
 556 acpi_status
 557 acpi_install_gpe_handler(acpi_handle gpe_device,
 558                          u32 gpe_number,
 559                          u32 type, acpi_event_handler address, void *context)
 560 {
 561         struct acpi_gpe_event_info *gpe_event_info;
 562         struct acpi_handler_info *handler;
 563         acpi_status status;
 564         acpi_cpu_flags flags;
 565
 566         ACPI_FUNCTION_TRACE(acpi_install_gpe_handler);
 567
 568         /* Parameter validation */
 569
 570         if ((!address) || (type > ACPI_GPE_XRUPT_TYPE_MASK)) {
 571                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 572         }
 573
 574         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 575         if (ACPI_FAILURE(status)) {
 576                 return_ACPI_STATUS(status);
 577         }
 578
 579         /* Ensure that we have a valid GPE number */
 580
 581         gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
 582         if (!gpe_event_info) {
 583                 status = AE_BAD_PARAMETER;
 584                 goto unlock_and_exit;
 585         }
 586
 587         /* Make sure that there isn't a handler there already */
 588
 589         if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
 590             ACPI_GPE_DISPATCH_HANDLER) {
 591                 status = AE_ALREADY_EXISTS;
 592                 goto unlock_and_exit;
 593         }
 594
 595         /* Allocate and init handler object */
 596
 597         handler = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_handler_info));
 598         if (!handler) {
 599                 status = AE_NO_MEMORY;
 600                 goto unlock_and_exit;
 601         }
 602
 603         handler->address = address;
 604         handler->context = context;
 605         handler->method_node = gpe_event_info->dispatch.method_node;
 606
 607         /* Disable the GPE before installing the handler */
 608
 609         status = acpi_ev_disable_gpe(gpe_event_info);
 610         if (ACPI_FAILURE(status)) {
 611                 goto unlock_and_exit;
 612         }
 613
 614         /* Install the handler */
 615
 616         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 617         gpe_event_info->dispatch.handler = handler;
 618
 619         /* Setup up dispatch flags to indicate handler (vs. method) */
 620
 621         gpe_event_info->flags &= ~(ACPI_GPE_XRUPT_TYPE_MASK | ACPI_GPE_DISPATCH_MASK);  /* Clear bits */
 622         gpe_event_info->flags |= (u8) (type | ACPI_GPE_DISPATCH_HANDLER);
 623
 624         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 625
 626       unlock_and_exit:
 627         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 628         return_ACPI_STATUS(status);
 629 }
 630
 631 ACPI_EXPORT_SYMBOL(acpi_install_gpe_handler)
 632
 633 /*******************************************************************************
 634  *
 635  * FUNCTION:    acpi_remove_gpe_handler
 636  *
 637  * PARAMETERS:  gpe_device      - Namespace node for the GPE (NULL for FADT
 638  *                                defined GPEs)
 639  *              gpe_number      - The event to remove a handler
 640  *              Address         - Address of the handler
 641  *
 642  * RETURN:      Status
 643  *
 644  * DESCRIPTION: Remove a handler for a General Purpose acpi_event.
 645  *
 646  ******************************************************************************/
 647 acpi_status
 648 acpi_remove_gpe_handler(acpi_handle gpe_device,
 649                         u32 gpe_number, acpi_event_handler address)
 650 {
 651         struct acpi_gpe_event_info *gpe_event_info;
 652         struct acpi_handler_info *handler;
 653         acpi_status status;
 654         acpi_cpu_flags flags;
 655
 656         ACPI_FUNCTION_TRACE(acpi_remove_gpe_handler);
 657
 658         /* Parameter validation */
 659
 660         if (!address) {
 661                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 662         }
 663
 664         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 665         if (ACPI_FAILURE(status)) {
 666                 return_ACPI_STATUS(status);
 667         }
 668
 669         /* Ensure that we have a valid GPE number */
 670
 671         gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
 672         if (!gpe_event_info) {
 673                 status = AE_BAD_PARAMETER;
 674                 goto unlock_and_exit;
 675         }
 676
 677         /* Make sure that a handler is indeed installed */
 678
 679         if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) !=
 680             ACPI_GPE_DISPATCH_HANDLER) {
 681                 status = AE_NOT_EXIST;
 682                 goto unlock_and_exit;
 683         }
 684
 685         /* Make sure that the installed handler is the same */
 686
 687         if (gpe_event_info->dispatch.handler->address != address) {
 688                 status = AE_BAD_PARAMETER;
 689                 goto unlock_and_exit;
 690         }
 691
 692         /* Disable the GPE before removing the handler */
 693
 694         status = acpi_ev_disable_gpe(gpe_event_info);
 695         if (ACPI_FAILURE(status)) {
 696                 goto unlock_and_exit;
 697         }
 698
 699         /* Make sure all deferred tasks are completed */
 700
 701         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 702         acpi_os_wait_events_complete(NULL);
 703         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 704         if (ACPI_FAILURE(status)) {
 705                 return_ACPI_STATUS(status);
 706         }
 707
 708         /* Remove the handler */
 709
 710         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 711         handler = gpe_event_info->dispatch.handler;
 712
 713         /* Restore Method node (if any), set dispatch flags */
 714
 715         gpe_event_info->dispatch.method_node = handler->method_node;
 716         gpe_event_info->flags &= ~ACPI_GPE_DISPATCH_MASK;       /* Clear bits */
 717         if (handler->method_node) {
 718                 gpe_event_info->flags |= ACPI_GPE_DISPATCH_METHOD;
 719         }
 720         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 721
 722         /* Now we can free the handler object */
 723
 724         ACPI_FREE(handler);
 725
 726       unlock_and_exit:
 727         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 728         return_ACPI_STATUS(status);
 729 }
 730
 731 ACPI_EXPORT_SYMBOL(acpi_remove_gpe_handler)
 732
 733 /*******************************************************************************
 734  *
 735  * FUNCTION:    acpi_acquire_global_lock
 736  *
 737  * PARAMETERS:  Timeout         - How long the caller is willing to wait
 738  *              Handle          - Where the handle to the lock is returned
 739  *                                (if acquired)
 740  *
 741  * RETURN:      Status
 742  *
 743  * DESCRIPTION: Acquire the ACPI Global Lock
 744  *
 745  ******************************************************************************/
 746 acpi_status acpi_acquire_global_lock(u16 timeout, u32 * handle)
 747 {
 748         acpi_status status;
 749
 750         if (!handle) {
 751                 return (AE_BAD_PARAMETER);
 752         }
 753
 754         status = acpi_ex_enter_interpreter();
 755         if (ACPI_FAILURE(status)) {
 756                 return (status);
 757         }
 758
 759         status = acpi_ev_acquire_global_lock(timeout);
 760         acpi_ex_exit_interpreter();
 761
 762         if (ACPI_SUCCESS(status)) {
 763                 acpi_gbl_global_lock_handle++;
 764                 *handle = acpi_gbl_global_lock_handle;
 765         }
 766
 767         return (status);
 768 }
 769
 770 ACPI_EXPORT_SYMBOL(acpi_acquire_global_lock)
 771
 772 /*******************************************************************************
 773  *
 774  * FUNCTION:    acpi_release_global_lock
 775  *
 776  * PARAMETERS:  Handle      - Returned from acpi_acquire_global_lock
 777  *
 778  * RETURN:      Status
 779  *
 780  * DESCRIPTION: Release the ACPI Global Lock. The handle must be valid.
 781  *
 782  ******************************************************************************/
 783 acpi_status acpi_release_global_lock(u32 handle)
 784 {
 785         acpi_status status;
 786
 787         if (handle != acpi_gbl_global_lock_handle) {
 788                 return (AE_NOT_ACQUIRED);
 789         }
 790
 791         status = acpi_ev_release_global_lock();
 792         return (status);
 793 }
 794
 795 ACPI_EXPORT_SYMBOL(acpi_release_global_lock)