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 <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_WARNING((AE_INFO, "Could not enable fixed event %X",
 147                               event));
 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_WARNING((AE_INFO,
 208                               "Could not write to fixed event enable register %X",
 209                               event));
 210         } else {
 211                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Disabled fixed event %X\n",
 212                                   event));
 213         }
 214
 215         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 216         return_ACPI_STATUS(status);
 217 }
 218
 219 EXPORT_SYMBOL(acpi_remove_fixed_event_handler);
 220
 221 /*******************************************************************************
 222  *
 223  * FUNCTION:    acpi_install_notify_handler
 224  *
 225  * PARAMETERS:  Device          - The device for which notifies will be handled
 226  *              handler_type    - The type of handler:
 227  *                                  ACPI_SYSTEM_NOTIFY: system_handler (00-7f)
 228  *                                  ACPI_DEVICE_NOTIFY: driver_handler (80-ff)
 229  *                                  ACPI_ALL_NOTIFY:  both system and device
 230  *              Handler         - Address of the handler
 231  *              Context         - Value passed to the handler on each GPE
 232  *
 233  * RETURN:      Status
 234  *
 235  * DESCRIPTION: Install a handler for notifies on an ACPI device
 236  *
 237  ******************************************************************************/
 238
 239 acpi_status
 240 acpi_install_notify_handler(acpi_handle device,
 241                             u32 handler_type,
 242                             acpi_notify_handler handler, void *context)
 243 {
 244         union acpi_operand_object *obj_desc;
 245         union acpi_operand_object *notify_obj;
 246         struct acpi_namespace_node *node;
 247         acpi_status status;
 248
 249         ACPI_FUNCTION_TRACE("acpi_install_notify_handler");
 250
 251         /* Parameter validation */
 252
 253         if ((!device) ||
 254             (!handler) || (handler_type > ACPI_MAX_NOTIFY_HANDLER_TYPE)) {
 255                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 256         }
 257
 258         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 259         if (ACPI_FAILURE(status)) {
 260                 return_ACPI_STATUS(status);
 261         }
 262
 263         /* Convert and validate the device handle */
 264
 265         node = acpi_ns_map_handle_to_node(device);
 266         if (!node) {
 267                 status = AE_BAD_PARAMETER;
 268                 goto unlock_and_exit;
 269         }
 270
 271         /*
 272          * Root Object:
 273          * Registering a notify handler on the root object indicates that the
 274          * caller wishes to receive notifications for all objects.  Note that
 275          * only one <external> global handler can be regsitered (per notify type).
 276          */
 277         if (device == ACPI_ROOT_OBJECT) {
 278                 /* Make sure the handler is not already installed */
 279
 280                 if (((handler_type & ACPI_SYSTEM_NOTIFY) &&
 281                      acpi_gbl_system_notify.handler) ||
 282                     ((handler_type & ACPI_DEVICE_NOTIFY) &&
 283                      acpi_gbl_device_notify.handler)) {
 284                         status = AE_ALREADY_EXISTS;
 285                         goto unlock_and_exit;
 286                 }
 287
 288                 if (handler_type & ACPI_SYSTEM_NOTIFY) {
 289                         acpi_gbl_system_notify.node = node;
 290                         acpi_gbl_system_notify.handler = handler;
 291                         acpi_gbl_system_notify.context = context;
 292                 }
 293
 294                 if (handler_type & ACPI_DEVICE_NOTIFY) {
 295                         acpi_gbl_device_notify.node = node;
 296                         acpi_gbl_device_notify.handler = handler;
 297                         acpi_gbl_device_notify.context = context;
 298                 }
 299
 300                 /* Global notify handler installed */
 301         }
 302
 303         /*
 304          * All Other Objects:
 305          * Caller will only receive notifications specific to the target object.
 306          * Note that only certain object types can receive notifications.
 307          */
 308         else {
 309                 /* Notifies allowed on this object? */
 310
 311                 if (!acpi_ev_is_notify_object(node)) {
 312                         status = AE_TYPE;
 313                         goto unlock_and_exit;
 314                 }
 315
 316                 /* Check for an existing internal object */
 317
 318                 obj_desc = acpi_ns_get_attached_object(node);
 319                 if (obj_desc) {
 320                         /* Object exists - make sure there's no handler */
 321
 322                         if (((handler_type & ACPI_SYSTEM_NOTIFY) &&
 323                              obj_desc->common_notify.system_notify) ||
 324                             ((handler_type & ACPI_DEVICE_NOTIFY) &&
 325                              obj_desc->common_notify.device_notify)) {
 326                                 status = AE_ALREADY_EXISTS;
 327                                 goto unlock_and_exit;
 328                         }
 329                 } else {
 330                         /* Create a new object */
 331
 332                         obj_desc = acpi_ut_create_internal_object(node->type);
 333                         if (!obj_desc) {
 334                                 status = AE_NO_MEMORY;
 335                                 goto unlock_and_exit;
 336                         }
 337
 338                         /* Attach new object to the Node */
 339
 340                         status =
 341                             acpi_ns_attach_object(device, obj_desc, node->type);
 342
 343                         /* Remove local reference to the object */
 344
 345                         acpi_ut_remove_reference(obj_desc);
 346                         if (ACPI_FAILURE(status)) {
 347                                 goto unlock_and_exit;
 348                         }
 349                 }
 350
 351                 /* Install the handler */
 352
 353                 notify_obj =
 354                     acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_NOTIFY);
 355                 if (!notify_obj) {
 356                         status = AE_NO_MEMORY;
 357                         goto unlock_and_exit;
 358                 }
 359
 360                 notify_obj->notify.node = node;
 361                 notify_obj->notify.handler = handler;
 362                 notify_obj->notify.context = context;
 363
 364                 if (handler_type & ACPI_SYSTEM_NOTIFY) {
 365                         obj_desc->common_notify.system_notify = notify_obj;
 366                 }
 367
 368                 if (handler_type & ACPI_DEVICE_NOTIFY) {
 369                         obj_desc->common_notify.device_notify = notify_obj;
 370                 }
 371
 372                 if (handler_type == ACPI_ALL_NOTIFY) {
 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 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
 403 acpi_status
 404 acpi_remove_notify_handler(acpi_handle device,
 405                            u32 handler_type, acpi_notify_handler handler)
 406 {
 407         union acpi_operand_object *notify_obj;
 408         union acpi_operand_object *obj_desc;
 409         struct acpi_namespace_node *node;
 410         acpi_status status;
 411
 412         ACPI_FUNCTION_TRACE("acpi_remove_notify_handler");
 413
 414         /* Parameter validation */
 415
 416         if ((!device) ||
 417             (!handler) || (handler_type > ACPI_MAX_NOTIFY_HANDLER_TYPE)) {
 418                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 419         }
 420
 421         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 422         if (ACPI_FAILURE(status)) {
 423                 return_ACPI_STATUS(status);
 424         }
 425
 426         /* Convert and validate the device handle */
 427
 428         node = acpi_ns_map_handle_to_node(device);
 429         if (!node) {
 430                 status = AE_BAD_PARAMETER;
 431                 goto unlock_and_exit;
 432         }
 433
 434         /* Root Object */
 435
 436         if (device == ACPI_ROOT_OBJECT) {
 437                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 438                                   "Removing notify handler for namespace root object\n"));
 439
 440                 if (((handler_type & ACPI_SYSTEM_NOTIFY) &&
 441                      !acpi_gbl_system_notify.handler) ||
 442                     ((handler_type & ACPI_DEVICE_NOTIFY) &&
 443                      !acpi_gbl_device_notify.handler)) {
 444                         status = AE_NOT_EXIST;
 445                         goto unlock_and_exit;
 446                 }
 447
 448                 /* Make sure all deferred tasks are completed */
 449
 450                 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 451                 acpi_os_wait_events_complete(NULL);
 452                 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 453                 if (ACPI_FAILURE(status)) {
 454                         return_ACPI_STATUS(status);
 455                 }
 456
 457                 if (handler_type & ACPI_SYSTEM_NOTIFY) {
 458                         acpi_gbl_system_notify.node = NULL;
 459                         acpi_gbl_system_notify.handler = NULL;
 460                         acpi_gbl_system_notify.context = NULL;
 461                 }
 462
 463                 if (handler_type & ACPI_DEVICE_NOTIFY) {
 464                         acpi_gbl_device_notify.node = NULL;
 465                         acpi_gbl_device_notify.handler = NULL;
 466                         acpi_gbl_device_notify.context = NULL;
 467                 }
 468         }
 469
 470         /* All Other Objects */
 471
 472         else {
 473                 /* Notifies allowed on this object? */
 474
 475                 if (!acpi_ev_is_notify_object(node)) {
 476                         status = AE_TYPE;
 477                         goto unlock_and_exit;
 478                 }
 479
 480                 /* Check for an existing internal object */
 481
 482                 obj_desc = acpi_ns_get_attached_object(node);
 483                 if (!obj_desc) {
 484                         status = AE_NOT_EXIST;
 485                         goto unlock_and_exit;
 486                 }
 487
 488                 /* Object exists - make sure there's an existing handler */
 489
 490                 if (handler_type & ACPI_SYSTEM_NOTIFY) {
 491                         notify_obj = obj_desc->common_notify.system_notify;
 492                         if ((!notify_obj) ||
 493                             (notify_obj->notify.handler != handler)) {
 494                                 status = AE_BAD_PARAMETER;
 495                                 goto unlock_and_exit;
 496                         }
 497                         /* Make sure all deferred tasks are completed */
 498
 499                         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 500                         acpi_os_wait_events_complete(NULL);
 501                         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 502                         if (ACPI_FAILURE(status)) {
 503                                 return_ACPI_STATUS(status);
 504                         }
 505
 506                         /* Remove the handler */
 507                         obj_desc->common_notify.system_notify = NULL;
 508                         acpi_ut_remove_reference(notify_obj);
 509                 }
 510
 511                 if (handler_type & ACPI_DEVICE_NOTIFY) {
 512                         notify_obj = obj_desc->common_notify.device_notify;
 513                         if ((!notify_obj) ||
 514                             (notify_obj->notify.handler != handler)) {
 515                                 status = AE_BAD_PARAMETER;
 516                                 goto unlock_and_exit;
 517                         }
 518                         /* Make sure all deferred tasks are completed */
 519
 520                         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 521                         acpi_os_wait_events_complete(NULL);
 522                         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 523                         if (ACPI_FAILURE(status)) {
 524                                 return_ACPI_STATUS(status);
 525                         }
 526
 527                         /* Remove the handler */
 528                         obj_desc->common_notify.device_notify = NULL;
 529                         acpi_ut_remove_reference(notify_obj);
 530                 }
 531         }
 532
 533       unlock_and_exit:
 534         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 535         return_ACPI_STATUS(status);
 536 }
 537
 538 EXPORT_SYMBOL(acpi_remove_notify_handler);
 539
 540 /*******************************************************************************
 541  *
 542  * FUNCTION:    acpi_install_gpe_handler
 543  *
 544  * PARAMETERS:  gpe_device      - Namespace node for the GPE (NULL for FADT
 545  *                                defined GPEs)
 546  *              gpe_number      - The GPE number within the GPE block
 547  *              Type            - Whether this GPE should be treated as an
 548  *                                edge- or level-triggered interrupt.
 549  *              Address         - Address of the handler
 550  *              Context         - Value passed to the handler on each GPE
 551  *
 552  * RETURN:      Status
 553  *
 554  * DESCRIPTION: Install a handler for a General Purpose Event.
 555  *
 556  ******************************************************************************/
 557
 558 acpi_status
 559 acpi_install_gpe_handler(acpi_handle gpe_device,
 560                          u32 gpe_number,
 561                          u32 type, acpi_event_handler address, void *context)
 562 {
 563         struct acpi_gpe_event_info *gpe_event_info;
 564         struct acpi_handler_info *handler;
 565         acpi_status status;
 566         acpi_cpu_flags flags;
 567
 568         ACPI_FUNCTION_TRACE("acpi_install_gpe_handler");
 569
 570         /* Parameter validation */
 571
 572         if ((!address) || (type > ACPI_GPE_XRUPT_TYPE_MASK)) {
 573                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 574         }
 575
 576         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 577         if (ACPI_FAILURE(status)) {
 578                 return_ACPI_STATUS(status);
 579         }
 580
 581         /* Ensure that we have a valid GPE number */
 582
 583         gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
 584         if (!gpe_event_info) {
 585                 status = AE_BAD_PARAMETER;
 586                 goto unlock_and_exit;
 587         }
 588
 589         /* Make sure that there isn't a handler there already */
 590
 591         if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
 592             ACPI_GPE_DISPATCH_HANDLER) {
 593                 status = AE_ALREADY_EXISTS;
 594                 goto unlock_and_exit;
 595         }
 596
 597         /* Allocate and init handler object */
 598
 599         handler = ACPI_MEM_CALLOCATE(sizeof(struct acpi_handler_info));
 600         if (!handler) {
 601                 status = AE_NO_MEMORY;
 602                 goto unlock_and_exit;
 603         }
 604
 605         handler->address = address;
 606         handler->context = context;
 607         handler->method_node = gpe_event_info->dispatch.method_node;
 608
 609         /* Disable the GPE before installing the handler */
 610
 611         status = acpi_ev_disable_gpe(gpe_event_info);
 612         if (ACPI_FAILURE(status)) {
 613                 goto unlock_and_exit;
 614         }
 615
 616         /* Install the handler */
 617
 618         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 619         gpe_event_info->dispatch.handler = handler;
 620
 621         /* Setup up dispatch flags to indicate handler (vs. method) */
 622
 623         gpe_event_info->flags &= ~(ACPI_GPE_XRUPT_TYPE_MASK | ACPI_GPE_DISPATCH_MASK);  /* Clear bits */
 624         gpe_event_info->flags |= (u8) (type | ACPI_GPE_DISPATCH_HANDLER);
 625
 626         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 627
 628       unlock_and_exit:
 629         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 630         return_ACPI_STATUS(status);
 631 }
 632
 633 EXPORT_SYMBOL(acpi_install_gpe_handler);
 634
 635 /*******************************************************************************
 636  *
 637  * FUNCTION:    acpi_remove_gpe_handler
 638  *
 639  * PARAMETERS:  gpe_device      - Namespace node for the GPE (NULL for FADT
 640  *                                defined GPEs)
 641  *              gpe_number      - The event to remove a handler
 642  *              Address         - Address of the handler
 643  *
 644  * RETURN:      Status
 645  *
 646  * DESCRIPTION: Remove a handler for a General Purpose acpi_event.
 647  *
 648  ******************************************************************************/
 649
 650 acpi_status
 651 acpi_remove_gpe_handler(acpi_handle gpe_device,
 652                         u32 gpe_number, acpi_event_handler address)
 653 {
 654         struct acpi_gpe_event_info *gpe_event_info;
 655         struct acpi_handler_info *handler;
 656         acpi_status status;
 657         acpi_cpu_flags flags;
 658
 659         ACPI_FUNCTION_TRACE("acpi_remove_gpe_handler");
 660
 661         /* Parameter validation */
 662
 663         if (!address) {
 664                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 665         }
 666
 667         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 668         if (ACPI_FAILURE(status)) {
 669                 return_ACPI_STATUS(status);
 670         }
 671
 672         /* Ensure that we have a valid GPE number */
 673
 674         gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
 675         if (!gpe_event_info) {
 676                 status = AE_BAD_PARAMETER;
 677                 goto unlock_and_exit;
 678         }
 679
 680         /* Make sure that a handler is indeed installed */
 681
 682         if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) !=
 683             ACPI_GPE_DISPATCH_HANDLER) {
 684                 status = AE_NOT_EXIST;
 685                 goto unlock_and_exit;
 686         }
 687
 688         /* Make sure that the installed handler is the same */
 689
 690         if (gpe_event_info->dispatch.handler->address != address) {
 691                 status = AE_BAD_PARAMETER;
 692                 goto unlock_and_exit;
 693         }
 694
 695         /* Disable the GPE before removing the handler */
 696
 697         status = acpi_ev_disable_gpe(gpe_event_info);
 698         if (ACPI_FAILURE(status)) {
 699                 goto unlock_and_exit;
 700         }
 701
 702         /* Make sure all deferred tasks are completed */
 703
 704         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 705         acpi_os_wait_events_complete(NULL);
 706         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 707         if (ACPI_FAILURE(status)) {
 708                 return_ACPI_STATUS(status);
 709         }
 710
 711         /* Remove the handler */
 712
 713         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 714         handler = gpe_event_info->dispatch.handler;
 715
 716         /* Restore Method node (if any), set dispatch flags */
 717
 718         gpe_event_info->dispatch.method_node = handler->method_node;
 719         gpe_event_info->flags &= ~ACPI_GPE_DISPATCH_MASK;       /* Clear bits */
 720         if (handler->method_node) {
 721                 gpe_event_info->flags |= ACPI_GPE_DISPATCH_METHOD;
 722         }
 723         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 724
 725         /* Now we can free the handler object */
 726
 727         ACPI_MEM_FREE(handler);
 728
 729       unlock_and_exit:
 730         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 731         return_ACPI_STATUS(status);
 732 }
 733
 734 EXPORT_SYMBOL(acpi_remove_gpe_handler);
 735
 736 /*******************************************************************************
 737  *
 738  * FUNCTION:    acpi_acquire_global_lock
 739  *
 740  * PARAMETERS:  Timeout         - How long the caller is willing to wait
 741  *              Handle          - Where the handle to the lock is returned
 742  *                                (if acquired)
 743  *
 744  * RETURN:      Status
 745  *
 746  * DESCRIPTION: Acquire the ACPI Global Lock
 747  *
 748  ******************************************************************************/
 749
 750 acpi_status acpi_acquire_global_lock(u16 timeout, u32 * handle)
 751 {
 752         acpi_status status;
 753
 754         if (!handle) {
 755                 return (AE_BAD_PARAMETER);
 756         }
 757
 758         status = acpi_ex_enter_interpreter();
 759         if (ACPI_FAILURE(status)) {
 760                 return (status);
 761         }
 762
 763         status = acpi_ev_acquire_global_lock(timeout);
 764         acpi_ex_exit_interpreter();
 765
 766         if (ACPI_SUCCESS(status)) {
 767                 acpi_gbl_global_lock_handle++;
 768                 *handle = acpi_gbl_global_lock_handle;
 769         }
 770
 771         return (status);
 772 }
 773
 774 EXPORT_SYMBOL(acpi_acquire_global_lock);
 775
 776 /*******************************************************************************
 777  *
 778  * FUNCTION:    acpi_release_global_lock
 779  *
 780  * PARAMETERS:  Handle      - Returned from acpi_acquire_global_lock
 781  *
 782  * RETURN:      Status
 783  *
 784  * DESCRIPTION: Release the ACPI Global Lock. The handle must be valid.
 785  *
 786  ******************************************************************************/
 787
 788 acpi_status acpi_release_global_lock(u32 handle)
 789 {
 790         acpi_status status;
 791
 792         if (handle != acpi_gbl_global_lock_handle) {
 793                 return (AE_NOT_ACQUIRED);
 794         }
 795
 796         status = acpi_ev_release_global_lock();
 797         return (status);
 798 }
 799
 800 EXPORT_SYMBOL(acpi_release_global_lock);