drivers/acpi/events/evxface.c

   1 /******************************************************************************
   2  *
   3  * Module Name: evxface - External interfaces for ACPI events
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2005, 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 <linux/module.h>
  45
  46 #include <acpi/acpi.h>
  47 #include <acpi/acnamesp.h>
  48 #include <acpi/acevents.h>
  49 #include <acpi/acinterp.h>
  50
  51 #define _COMPONENT          ACPI_EVENTS
  52 ACPI_MODULE_NAME("evxface")
  53
  54 /*******************************************************************************
  55  *
  56  * FUNCTION:    acpi_install_exception_handler
  57  *
  58  * PARAMETERS:  Handler         - Pointer to the handler function for the
  59  *                                event
  60  *
  61  * RETURN:      Status
  62  *
  63  * DESCRIPTION: Saves the pointer to the handler function
  64  *
  65  ******************************************************************************/
  66 #ifdef ACPI_FUTURE_USAGE
  67 acpi_status acpi_install_exception_handler(acpi_exception_handler handler)
  68 {
  69         acpi_status status;
  70
  71         ACPI_FUNCTION_TRACE("acpi_install_exception_handler");
  72
  73         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
  74         if (ACPI_FAILURE(status)) {
  75                 return_ACPI_STATUS(status);
  76         }
  77
  78         /* Don't allow two handlers. */
  79
  80         if (acpi_gbl_exception_handler) {
  81                 status = AE_ALREADY_EXISTS;
  82                 goto cleanup;
  83         }
  84
  85         /* Install the handler */
  86
  87         acpi_gbl_exception_handler = handler;
  88
  89       cleanup:
  90         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
  91         return_ACPI_STATUS(status);
  92 }
  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
 111 acpi_status
 112 acpi_install_fixed_event_handler(u32 event,
 113                                  acpi_event_handler handler, void *context)
 114 {
 115         acpi_status status;
 116
 117         ACPI_FUNCTION_TRACE("acpi_install_fixed_event_handler");
 118
 119         /* Parameter validation */
 120
 121         if (event > ACPI_EVENT_MAX) {
 122                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 123         }
 124
 125         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 126         if (ACPI_FAILURE(status)) {
 127                 return_ACPI_STATUS(status);
 128         }
 129
 130         /* Don't allow two handlers. */
 131
 132         if (NULL != acpi_gbl_fixed_event_handlers[event].handler) {
 133                 status = AE_ALREADY_EXISTS;
 134                 goto cleanup;
 135         }
 136
 137         /* Install the handler before enabling the event */
 138
 139         acpi_gbl_fixed_event_handlers[event].handler = handler;
 140         acpi_gbl_fixed_event_handlers[event].context = context;
 141
 142         status = acpi_clear_event(event);
 143         if (ACPI_SUCCESS(status))
 144                 status = acpi_enable_event(event, 0);
 145         if (ACPI_FAILURE(status)) {
 146                 ACPI_DEBUG_PRINT((ACPI_DB_WARN,
 147                                   "Could not enable fixed event.\n"));
 148
 149                 /* Remove the handler */
 150
 151                 acpi_gbl_fixed_event_handlers[event].handler = NULL;
 152                 acpi_gbl_fixed_event_handlers[event].context = NULL;
 153         } else {
 154                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 155                                   "Enabled fixed event %X, Handler=%p\n", event,
 156                                   handler));
 157         }
 158
 159       cleanup:
 160         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 161         return_ACPI_STATUS(status);
 162 }
 163
 164 EXPORT_SYMBOL(acpi_install_fixed_event_handler);
 165
 166 /*******************************************************************************
 167  *
 168  * FUNCTION:    acpi_remove_fixed_event_handler
 169  *
 170  * PARAMETERS:  Event           - Event type to disable.
 171  *              Handler         - Address of the handler
 172  *
 173  * RETURN:      Status
 174  *
 175  * DESCRIPTION: Disables the event and unregisters the event handler.
 176  *
 177  ******************************************************************************/
 178
 179 acpi_status
 180 acpi_remove_fixed_event_handler(u32 event, acpi_event_handler handler)
 181 {
 182         acpi_status status = AE_OK;
 183
 184         ACPI_FUNCTION_TRACE("acpi_remove_fixed_event_handler");
 185
 186         /* Parameter validation */
 187
 188         if (event > ACPI_EVENT_MAX) {
 189                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 190         }
 191
 192         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 193         if (ACPI_FAILURE(status)) {
 194                 return_ACPI_STATUS(status);
 195         }
 196
 197         /* Disable the event before removing the handler */
 198
 199         status = acpi_disable_event(event, 0);
 200
 201         /* Always Remove the handler */
 202
 203         acpi_gbl_fixed_event_handlers[event].handler = NULL;
 204         acpi_gbl_fixed_event_handlers[event].context = NULL;
 205
 206         if (ACPI_FAILURE(status)) {
 207                 ACPI_DEBUG_PRINT((ACPI_DB_WARN,
 208                                   "Could not write to fixed event enable register.\n"));
 209         } else {
 210                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Disabled fixed event %X.\n",
 211                                   event));
 212         }
 213
 214         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 215         return_ACPI_STATUS(status);
 216 }
 217
 218 EXPORT_SYMBOL(acpi_remove_fixed_event_handler);
 219
 220 /*******************************************************************************
 221  *
 222  * FUNCTION:    acpi_install_notify_handler
 223  *
 224  * PARAMETERS:  Device          - The device for which notifies will be handled
 225  *              handler_type    - The type of handler:
 226  *                                  ACPI_SYSTEM_NOTIFY: system_handler (00-7f)
 227  *                                  ACPI_DEVICE_NOTIFY: driver_handler (80-ff)
 228  *                                  ACPI_ALL_NOTIFY:  both system and device
 229  *              Handler         - Address of the handler
 230  *              Context         - Value passed to the handler on each GPE
 231  *
 232  * RETURN:      Status
 233  *
 234  * DESCRIPTION: Install a handler for notifies on an ACPI device
 235  *
 236  ******************************************************************************/
 237
 238 acpi_status
 239 acpi_install_notify_handler(acpi_handle device,
 240                             u32 handler_type,
 241                             acpi_notify_handler handler, void *context)
 242 {
 243         union acpi_operand_object *obj_desc;
 244         union acpi_operand_object *notify_obj;
 245         struct acpi_namespace_node *node;
 246         acpi_status status;
 247
 248         ACPI_FUNCTION_TRACE("acpi_install_notify_handler");
 249
 250         /* Parameter validation */
 251
 252         if ((!device) ||
 253             (!handler) || (handler_type > ACPI_MAX_NOTIFY_HANDLER_TYPE)) {
 254                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 255         }
 256
 257         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 258         if (ACPI_FAILURE(status)) {
 259                 return_ACPI_STATUS(status);
 260         }
 261
 262         /* Convert and validate the device handle */
 263
 264         node = acpi_ns_map_handle_to_node(device);
 265         if (!node) {
 266                 status = AE_BAD_PARAMETER;
 267                 goto unlock_and_exit;
 268         }
 269
 270         /*
 271          * Root Object:
 272          * Registering a notify handler on the root object indicates that the
 273          * caller wishes to receive notifications for all objects.  Note that
 274          * only one <external> global handler can be regsitered (per notify type).
 275          */
 276         if (device == ACPI_ROOT_OBJECT) {
 277                 /* Make sure the handler is not already installed */
 278
 279                 if (((handler_type & ACPI_SYSTEM_NOTIFY) &&
 280                      acpi_gbl_system_notify.handler) ||
 281                     ((handler_type & ACPI_DEVICE_NOTIFY) &&
 282                      acpi_gbl_device_notify.handler)) {
 283                         status = AE_ALREADY_EXISTS;
 284                         goto unlock_and_exit;
 285                 }
 286
 287                 if (handler_type & ACPI_SYSTEM_NOTIFY) {
 288                         acpi_gbl_system_notify.node = node;
 289                         acpi_gbl_system_notify.handler = handler;
 290                         acpi_gbl_system_notify.context = context;
 291                 }
 292
 293                 if (handler_type & ACPI_DEVICE_NOTIFY) {
 294                         acpi_gbl_device_notify.node = node;
 295                         acpi_gbl_device_notify.handler = handler;
 296                         acpi_gbl_device_notify.context = context;
 297                 }
 298
 299                 /* Global notify handler installed */
 300         }
 301
 302         /*
 303          * All Other Objects:
 304          * Caller will only receive notifications specific to the target object.
 305          * Note that only certain object types can receive notifications.
 306          */
 307         else {
 308                 /* Notifies allowed on this object? */
 309
 310                 if (!acpi_ev_is_notify_object(node)) {
 311                         status = AE_TYPE;
 312                         goto unlock_and_exit;
 313                 }
 314
 315                 /* Check for an existing internal object */
 316
 317                 obj_desc = acpi_ns_get_attached_object(node);
 318                 if (obj_desc) {
 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                         /* 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 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
 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 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 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
 557 acpi_status
 558 acpi_install_gpe_handler(acpi_handle gpe_device,
 559                          u32 gpe_number,
 560                          u32 type, acpi_event_handler address, void *context)
 561 {
 562         struct acpi_gpe_event_info *gpe_event_info;
 563         struct acpi_handler_info *handler;
 564         acpi_status status;
 565         acpi_native_uint flags;
 566
 567         ACPI_FUNCTION_TRACE("acpi_install_gpe_handler");
 568
 569         /* Parameter validation */
 570
 571         if ((!address) || (type > ACPI_GPE_XRUPT_TYPE_MASK)) {
 572                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 573         }
 574
 575         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 576         if (ACPI_FAILURE(status)) {
 577                 return_ACPI_STATUS(status);
 578         }
 579
 580         /* Ensure that we have a valid GPE number */
 581
 582         gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
 583         if (!gpe_event_info) {
 584                 status = AE_BAD_PARAMETER;
 585                 goto unlock_and_exit;
 586         }
 587
 588         /* Make sure that there isn't a handler there already */
 589
 590         if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
 591             ACPI_GPE_DISPATCH_HANDLER) {
 592                 status = AE_ALREADY_EXISTS;
 593                 goto unlock_and_exit;
 594         }
 595
 596         /* Allocate and init handler object */
 597
 598         handler = ACPI_MEM_CALLOCATE(sizeof(struct acpi_handler_info));
 599         if (!handler) {
 600                 status = AE_NO_MEMORY;
 601                 goto unlock_and_exit;
 602         }
 603
 604         handler->address = address;
 605         handler->context = context;
 606         handler->method_node = gpe_event_info->dispatch.method_node;
 607
 608         /* Disable the GPE before installing the handler */
 609
 610         status = acpi_ev_disable_gpe(gpe_event_info);
 611         if (ACPI_FAILURE(status)) {
 612                 goto unlock_and_exit;
 613         }
 614
 615         /* Install the handler */
 616
 617         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 618         gpe_event_info->dispatch.handler = handler;
 619
 620         /* Setup up dispatch flags to indicate handler (vs. method) */
 621
 622         gpe_event_info->flags &= ~(ACPI_GPE_XRUPT_TYPE_MASK | ACPI_GPE_DISPATCH_MASK);  /* Clear bits */
 623         gpe_event_info->flags |= (u8) (type | ACPI_GPE_DISPATCH_HANDLER);
 624
 625         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 626
 627       unlock_and_exit:
 628         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 629         return_ACPI_STATUS(status);
 630 }
 631
 632 EXPORT_SYMBOL(acpi_install_gpe_handler);
 633
 634 /*******************************************************************************
 635  *
 636  * FUNCTION:    acpi_remove_gpe_handler
 637  *
 638  * PARAMETERS:  gpe_device      - Namespace node for the GPE (NULL for FADT
 639  *                                defined GPEs)
 640  *              gpe_number      - The event to remove a handler
 641  *              Address         - Address of the handler
 642  *
 643  * RETURN:      Status
 644  *
 645  * DESCRIPTION: Remove a handler for a General Purpose acpi_event.
 646  *
 647  ******************************************************************************/
 648
 649 acpi_status
 650 acpi_remove_gpe_handler(acpi_handle gpe_device,
 651                         u32 gpe_number, acpi_event_handler address)
 652 {
 653         struct acpi_gpe_event_info *gpe_event_info;
 654         struct acpi_handler_info *handler;
 655         acpi_status status;
 656         acpi_native_uint flags;
 657
 658         ACPI_FUNCTION_TRACE("acpi_remove_gpe_handler");
 659
 660         /* Parameter validation */
 661
 662         if (!address) {
 663                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 664         }
 665
 666         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 667         if (ACPI_FAILURE(status)) {
 668                 return_ACPI_STATUS(status);
 669         }
 670
 671         /* Ensure that we have a valid GPE number */
 672
 673         gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
 674         if (!gpe_event_info) {
 675                 status = AE_BAD_PARAMETER;
 676                 goto unlock_and_exit;
 677         }
 678
 679         /* Make sure that a handler is indeed installed */
 680
 681         if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) !=
 682             ACPI_GPE_DISPATCH_HANDLER) {
 683                 status = AE_NOT_EXIST;
 684                 goto unlock_and_exit;
 685         }
 686
 687         /* Make sure that the installed handler is the same */
 688
 689         if (gpe_event_info->dispatch.handler->address != address) {
 690                 status = AE_BAD_PARAMETER;
 691                 goto unlock_and_exit;
 692         }
 693
 694         /* Disable the GPE before removing the handler */
 695
 696         status = acpi_ev_disable_gpe(gpe_event_info);
 697         if (ACPI_FAILURE(status)) {
 698                 goto unlock_and_exit;
 699         }
 700
 701         /* Make sure all deferred tasks are completed */
 702
 703         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 704         acpi_os_wait_events_complete(NULL);
 705         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 706         if (ACPI_FAILURE(status)) {
 707                 return_ACPI_STATUS(status);
 708         }
 709
 710         /* Remove the handler */
 711
 712         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 713         handler = gpe_event_info->dispatch.handler;
 714
 715         /* Restore Method node (if any), set dispatch flags */
 716
 717         gpe_event_info->dispatch.method_node = handler->method_node;
 718         gpe_event_info->flags &= ~ACPI_GPE_DISPATCH_MASK;       /* Clear bits */
 719         if (handler->method_node) {
 720                 gpe_event_info->flags |= ACPI_GPE_DISPATCH_METHOD;
 721         }
 722         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 723
 724         /* Now we can free the handler object */
 725
 726         ACPI_MEM_FREE(handler);
 727
 728       unlock_and_exit:
 729         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 730         return_ACPI_STATUS(status);
 731 }
 732
 733 EXPORT_SYMBOL(acpi_remove_gpe_handler);
 734
 735 /*******************************************************************************
 736  *
 737  * FUNCTION:    acpi_acquire_global_lock
 738  *
 739  * PARAMETERS:  Timeout         - How long the caller is willing to wait
 740  *              Handle          - Where the handle to the lock is returned
 741  *                                (if acquired)
 742  *
 743  * RETURN:      Status
 744  *
 745  * DESCRIPTION: Acquire the ACPI Global Lock
 746  *
 747  ******************************************************************************/
 748
 749 acpi_status acpi_acquire_global_lock(u16 timeout, u32 * handle)
 750 {
 751         acpi_status status;
 752
 753         if (!handle) {
 754                 return (AE_BAD_PARAMETER);
 755         }
 756
 757         status = acpi_ex_enter_interpreter();
 758         if (ACPI_FAILURE(status)) {
 759                 return (status);
 760         }
 761
 762         status = acpi_ev_acquire_global_lock(timeout);
 763         acpi_ex_exit_interpreter();
 764
 765         if (ACPI_SUCCESS(status)) {
 766                 acpi_gbl_global_lock_handle++;
 767                 *handle = acpi_gbl_global_lock_handle;
 768         }
 769
 770         return (status);
 771 }
 772
 773 EXPORT_SYMBOL(acpi_acquire_global_lock);
 774
 775 /*******************************************************************************
 776  *
 777  * FUNCTION:    acpi_release_global_lock
 778  *
 779  * PARAMETERS:  Handle      - Returned from acpi_acquire_global_lock
 780  *
 781  * RETURN:      Status
 782  *
 783  * DESCRIPTION: Release the ACPI Global Lock. The handle must be valid.
 784  *
 785  ******************************************************************************/
 786
 787 acpi_status acpi_release_global_lock(u32 handle)
 788 {
 789         acpi_status status;
 790
 791         if (handle != acpi_gbl_global_lock_handle) {
 792                 return (AE_NOT_ACQUIRED);
 793         }
 794
 795         status = acpi_ev_release_global_lock();
 796         return (status);
 797 }
 798
 799 EXPORT_SYMBOL(acpi_release_global_lock);