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
 279                 /* Make sure the handler is not already installed */
 280
 281                 if (((handler_type & ACPI_SYSTEM_NOTIFY) &&
 282                      acpi_gbl_system_notify.handler) ||
 283                     ((handler_type & ACPI_DEVICE_NOTIFY) &&
 284                      acpi_gbl_device_notify.handler)) {
 285                         status = AE_ALREADY_EXISTS;
 286                         goto unlock_and_exit;
 287                 }
 288
 289                 if (handler_type & ACPI_SYSTEM_NOTIFY) {
 290                         acpi_gbl_system_notify.node = node;
 291                         acpi_gbl_system_notify.handler = handler;
 292                         acpi_gbl_system_notify.context = context;
 293                 }
 294
 295                 if (handler_type & ACPI_DEVICE_NOTIFY) {
 296                         acpi_gbl_device_notify.node = node;
 297                         acpi_gbl_device_notify.handler = handler;
 298                         acpi_gbl_device_notify.context = context;
 299                 }
 300
 301                 /* Global notify handler installed */
 302         }
 303
 304         /*
 305          * All Other Objects:
 306          * Caller will only receive notifications specific to the target object.
 307          * Note that only certain object types can receive notifications.
 308          */
 309         else {
 310                 /* Notifies allowed on this object? */
 311
 312                 if (!acpi_ev_is_notify_object(node)) {
 313                         status = AE_TYPE;
 314                         goto unlock_and_exit;
 315                 }
 316
 317                 /* Check for an existing internal object */
 318
 319                 obj_desc = acpi_ns_get_attached_object(node);
 320                 if (obj_desc) {
 321
 322                         /* Object exists - make sure there's no handler */
 323
 324                         if (((handler_type & ACPI_SYSTEM_NOTIFY) &&
 325                              obj_desc->common_notify.system_notify) ||
 326                             ((handler_type & ACPI_DEVICE_NOTIFY) &&
 327                              obj_desc->common_notify.device_notify)) {
 328                                 status = AE_ALREADY_EXISTS;
 329                                 goto unlock_and_exit;
 330                         }
 331                 } else {
 332                         /* Create a new object */
 333
 334                         obj_desc = acpi_ut_create_internal_object(node->type);
 335                         if (!obj_desc) {
 336                                 status = AE_NO_MEMORY;
 337                                 goto unlock_and_exit;
 338                         }
 339
 340                         /* Attach new object to the Node */
 341
 342                         status =
 343                             acpi_ns_attach_object(device, obj_desc, node->type);
 344
 345                         /* Remove local reference to the object */
 346
 347                         acpi_ut_remove_reference(obj_desc);
 348                         if (ACPI_FAILURE(status)) {
 349                                 goto unlock_and_exit;
 350                         }
 351                 }
 352
 353                 /* Install the handler */
 354
 355                 notify_obj =
 356                     acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_NOTIFY);
 357                 if (!notify_obj) {
 358                         status = AE_NO_MEMORY;
 359                         goto unlock_and_exit;
 360                 }
 361
 362                 notify_obj->notify.node = node;
 363                 notify_obj->notify.handler = handler;
 364                 notify_obj->notify.context = context;
 365
 366                 if (handler_type & ACPI_SYSTEM_NOTIFY) {
 367                         obj_desc->common_notify.system_notify = notify_obj;
 368                 }
 369
 370                 if (handler_type & ACPI_DEVICE_NOTIFY) {
 371                         obj_desc->common_notify.device_notify = notify_obj;
 372                 }
 373
 374                 if (handler_type == ACPI_ALL_NOTIFY) {
 375
 376                         /* Extra ref if installed in both */
 377
 378                         acpi_ut_add_reference(notify_obj);
 379                 }
 380         }
 381
 382       unlock_and_exit:
 383         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 384         return_ACPI_STATUS(status);
 385 }
 386
 387 EXPORT_SYMBOL(acpi_install_notify_handler);
 388
 389 /*******************************************************************************
 390  *
 391  * FUNCTION:    acpi_remove_notify_handler
 392  *
 393  * PARAMETERS:  Device          - The device for which notifies will be handled
 394  *              handler_type    - The type of handler:
 395  *                                  ACPI_SYSTEM_NOTIFY: system_handler (00-7f)
 396  *                                  ACPI_DEVICE_NOTIFY: driver_handler (80-ff)
 397  *                                  ACPI_ALL_NOTIFY:  both system and device
 398  *              Handler         - Address of the handler
 399  *
 400  * RETURN:      Status
 401  *
 402  * DESCRIPTION: Remove a handler for notifies on an ACPI device
 403  *
 404  ******************************************************************************/
 405
 406 acpi_status
 407 acpi_remove_notify_handler(acpi_handle device,
 408                            u32 handler_type, acpi_notify_handler handler)
 409 {
 410         union acpi_operand_object *notify_obj;
 411         union acpi_operand_object *obj_desc;
 412         struct acpi_namespace_node *node;
 413         acpi_status status;
 414
 415         ACPI_FUNCTION_TRACE("acpi_remove_notify_handler");
 416
 417         /* Parameter validation */
 418
 419         if ((!device) ||
 420             (!handler) || (handler_type > ACPI_MAX_NOTIFY_HANDLER_TYPE)) {
 421                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 422         }
 423
 424         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 425         if (ACPI_FAILURE(status)) {
 426                 return_ACPI_STATUS(status);
 427         }
 428
 429         /* Convert and validate the device handle */
 430
 431         node = acpi_ns_map_handle_to_node(device);
 432         if (!node) {
 433                 status = AE_BAD_PARAMETER;
 434                 goto unlock_and_exit;
 435         }
 436
 437         /* Root Object */
 438
 439         if (device == ACPI_ROOT_OBJECT) {
 440                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 441                                   "Removing notify handler for namespace root object\n"));
 442
 443                 if (((handler_type & ACPI_SYSTEM_NOTIFY) &&
 444                      !acpi_gbl_system_notify.handler) ||
 445                     ((handler_type & ACPI_DEVICE_NOTIFY) &&
 446                      !acpi_gbl_device_notify.handler)) {
 447                         status = AE_NOT_EXIST;
 448                         goto unlock_and_exit;
 449                 }
 450
 451                 /* Make sure all deferred tasks are completed */
 452
 453                 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 454                 acpi_os_wait_events_complete(NULL);
 455                 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 456                 if (ACPI_FAILURE(status)) {
 457                         return_ACPI_STATUS(status);
 458                 }
 459
 460                 if (handler_type & ACPI_SYSTEM_NOTIFY) {
 461                         acpi_gbl_system_notify.node = NULL;
 462                         acpi_gbl_system_notify.handler = NULL;
 463                         acpi_gbl_system_notify.context = NULL;
 464                 }
 465
 466                 if (handler_type & ACPI_DEVICE_NOTIFY) {
 467                         acpi_gbl_device_notify.node = NULL;
 468                         acpi_gbl_device_notify.handler = NULL;
 469                         acpi_gbl_device_notify.context = NULL;
 470                 }
 471         }
 472
 473         /* All Other Objects */
 474
 475         else {
 476                 /* Notifies allowed on this object? */
 477
 478                 if (!acpi_ev_is_notify_object(node)) {
 479                         status = AE_TYPE;
 480                         goto unlock_and_exit;
 481                 }
 482
 483                 /* Check for an existing internal object */
 484
 485                 obj_desc = acpi_ns_get_attached_object(node);
 486                 if (!obj_desc) {
 487                         status = AE_NOT_EXIST;
 488                         goto unlock_and_exit;
 489                 }
 490
 491                 /* Object exists - make sure there's an existing handler */
 492
 493                 if (handler_type & ACPI_SYSTEM_NOTIFY) {
 494                         notify_obj = obj_desc->common_notify.system_notify;
 495                         if ((!notify_obj) ||
 496                             (notify_obj->notify.handler != handler)) {
 497                                 status = AE_BAD_PARAMETER;
 498                                 goto unlock_and_exit;
 499                         }
 500                         /* Make sure all deferred tasks are completed */
 501
 502                         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 503                         acpi_os_wait_events_complete(NULL);
 504                         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 505                         if (ACPI_FAILURE(status)) {
 506                                 return_ACPI_STATUS(status);
 507                         }
 508
 509                         /* Remove the handler */
 510                         obj_desc->common_notify.system_notify = NULL;
 511                         acpi_ut_remove_reference(notify_obj);
 512                 }
 513
 514                 if (handler_type & ACPI_DEVICE_NOTIFY) {
 515                         notify_obj = obj_desc->common_notify.device_notify;
 516                         if ((!notify_obj) ||
 517                             (notify_obj->notify.handler != handler)) {
 518                                 status = AE_BAD_PARAMETER;
 519                                 goto unlock_and_exit;
 520                         }
 521                         /* Make sure all deferred tasks are completed */
 522
 523                         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 524                         acpi_os_wait_events_complete(NULL);
 525                         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 526                         if (ACPI_FAILURE(status)) {
 527                                 return_ACPI_STATUS(status);
 528                         }
 529
 530                         /* Remove the handler */
 531                         obj_desc->common_notify.device_notify = NULL;
 532                         acpi_ut_remove_reference(notify_obj);
 533                 }
 534         }
 535
 536       unlock_and_exit:
 537         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 538         return_ACPI_STATUS(status);
 539 }
 540
 541 EXPORT_SYMBOL(acpi_remove_notify_handler);
 542
 543 /*******************************************************************************
 544  *
 545  * FUNCTION:    acpi_install_gpe_handler
 546  *
 547  * PARAMETERS:  gpe_device      - Namespace node for the GPE (NULL for FADT
 548  *                                defined GPEs)
 549  *              gpe_number      - The GPE number within the GPE block
 550  *              Type            - Whether this GPE should be treated as an
 551  *                                edge- or level-triggered interrupt.
 552  *              Address         - Address of the handler
 553  *              Context         - Value passed to the handler on each GPE
 554  *
 555  * RETURN:      Status
 556  *
 557  * DESCRIPTION: Install a handler for a General Purpose Event.
 558  *
 559  ******************************************************************************/
 560
 561 acpi_status
 562 acpi_install_gpe_handler(acpi_handle gpe_device,
 563                          u32 gpe_number,
 564                          u32 type, acpi_event_handler address, void *context)
 565 {
 566         struct acpi_gpe_event_info *gpe_event_info;
 567         struct acpi_handler_info *handler;
 568         acpi_status status;
 569         acpi_cpu_flags flags;
 570
 571         ACPI_FUNCTION_TRACE("acpi_install_gpe_handler");
 572
 573         /* Parameter validation */
 574
 575         if ((!address) || (type > ACPI_GPE_XRUPT_TYPE_MASK)) {
 576                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 577         }
 578
 579         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 580         if (ACPI_FAILURE(status)) {
 581                 return_ACPI_STATUS(status);
 582         }
 583
 584         /* Ensure that we have a valid GPE number */
 585
 586         gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
 587         if (!gpe_event_info) {
 588                 status = AE_BAD_PARAMETER;
 589                 goto unlock_and_exit;
 590         }
 591
 592         /* Make sure that there isn't a handler there already */
 593
 594         if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
 595             ACPI_GPE_DISPATCH_HANDLER) {
 596                 status = AE_ALREADY_EXISTS;
 597                 goto unlock_and_exit;
 598         }
 599
 600         /* Allocate and init handler object */
 601
 602         handler = ACPI_MEM_CALLOCATE(sizeof(struct acpi_handler_info));
 603         if (!handler) {
 604                 status = AE_NO_MEMORY;
 605                 goto unlock_and_exit;
 606         }
 607
 608         handler->address = address;
 609         handler->context = context;
 610         handler->method_node = gpe_event_info->dispatch.method_node;
 611
 612         /* Disable the GPE before installing the handler */
 613
 614         status = acpi_ev_disable_gpe(gpe_event_info);
 615         if (ACPI_FAILURE(status)) {
 616                 goto unlock_and_exit;
 617         }
 618
 619         /* Install the handler */
 620
 621         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 622         gpe_event_info->dispatch.handler = handler;
 623
 624         /* Setup up dispatch flags to indicate handler (vs. method) */
 625
 626         gpe_event_info->flags &= ~(ACPI_GPE_XRUPT_TYPE_MASK | ACPI_GPE_DISPATCH_MASK);  /* Clear bits */
 627         gpe_event_info->flags |= (u8) (type | ACPI_GPE_DISPATCH_HANDLER);
 628
 629         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 630
 631       unlock_and_exit:
 632         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 633         return_ACPI_STATUS(status);
 634 }
 635
 636 EXPORT_SYMBOL(acpi_install_gpe_handler);
 637
 638 /*******************************************************************************
 639  *
 640  * FUNCTION:    acpi_remove_gpe_handler
 641  *
 642  * PARAMETERS:  gpe_device      - Namespace node for the GPE (NULL for FADT
 643  *                                defined GPEs)
 644  *              gpe_number      - The event to remove a handler
 645  *              Address         - Address of the handler
 646  *
 647  * RETURN:      Status
 648  *
 649  * DESCRIPTION: Remove a handler for a General Purpose acpi_event.
 650  *
 651  ******************************************************************************/
 652
 653 acpi_status
 654 acpi_remove_gpe_handler(acpi_handle gpe_device,
 655                         u32 gpe_number, acpi_event_handler address)
 656 {
 657         struct acpi_gpe_event_info *gpe_event_info;
 658         struct acpi_handler_info *handler;
 659         acpi_status status;
 660         acpi_cpu_flags flags;
 661
 662         ACPI_FUNCTION_TRACE("acpi_remove_gpe_handler");
 663
 664         /* Parameter validation */
 665
 666         if (!address) {
 667                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 668         }
 669
 670         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 671         if (ACPI_FAILURE(status)) {
 672                 return_ACPI_STATUS(status);
 673         }
 674
 675         /* Ensure that we have a valid GPE number */
 676
 677         gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
 678         if (!gpe_event_info) {
 679                 status = AE_BAD_PARAMETER;
 680                 goto unlock_and_exit;
 681         }
 682
 683         /* Make sure that a handler is indeed installed */
 684
 685         if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) !=
 686             ACPI_GPE_DISPATCH_HANDLER) {
 687                 status = AE_NOT_EXIST;
 688                 goto unlock_and_exit;
 689         }
 690
 691         /* Make sure that the installed handler is the same */
 692
 693         if (gpe_event_info->dispatch.handler->address != address) {
 694                 status = AE_BAD_PARAMETER;
 695                 goto unlock_and_exit;
 696         }
 697
 698         /* Disable the GPE before removing the handler */
 699
 700         status = acpi_ev_disable_gpe(gpe_event_info);
 701         if (ACPI_FAILURE(status)) {
 702                 goto unlock_and_exit;
 703         }
 704
 705         /* Make sure all deferred tasks are completed */
 706
 707         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 708         acpi_os_wait_events_complete(NULL);
 709         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 710         if (ACPI_FAILURE(status)) {
 711                 return_ACPI_STATUS(status);
 712         }
 713
 714         /* Remove the handler */
 715
 716         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 717         handler = gpe_event_info->dispatch.handler;
 718
 719         /* Restore Method node (if any), set dispatch flags */
 720
 721         gpe_event_info->dispatch.method_node = handler->method_node;
 722         gpe_event_info->flags &= ~ACPI_GPE_DISPATCH_MASK;       /* Clear bits */
 723         if (handler->method_node) {
 724                 gpe_event_info->flags |= ACPI_GPE_DISPATCH_METHOD;
 725         }
 726         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 727
 728         /* Now we can free the handler object */
 729
 730         ACPI_MEM_FREE(handler);
 731
 732       unlock_and_exit:
 733         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 734         return_ACPI_STATUS(status);
 735 }
 736
 737 EXPORT_SYMBOL(acpi_remove_gpe_handler);
 738
 739 /*******************************************************************************
 740  *
 741  * FUNCTION:    acpi_acquire_global_lock
 742  *
 743  * PARAMETERS:  Timeout         - How long the caller is willing to wait
 744  *              Handle          - Where the handle to the lock is returned
 745  *                                (if acquired)
 746  *
 747  * RETURN:      Status
 748  *
 749  * DESCRIPTION: Acquire the ACPI Global Lock
 750  *
 751  ******************************************************************************/
 752
 753 acpi_status acpi_acquire_global_lock(u16 timeout, u32 * handle)
 754 {
 755         acpi_status status;
 756
 757         if (!handle) {
 758                 return (AE_BAD_PARAMETER);
 759         }
 760
 761         status = acpi_ex_enter_interpreter();
 762         if (ACPI_FAILURE(status)) {
 763                 return (status);
 764         }
 765
 766         status = acpi_ev_acquire_global_lock(timeout);
 767         acpi_ex_exit_interpreter();
 768
 769         if (ACPI_SUCCESS(status)) {
 770                 acpi_gbl_global_lock_handle++;
 771                 *handle = acpi_gbl_global_lock_handle;
 772         }
 773
 774         return (status);
 775 }
 776
 777 EXPORT_SYMBOL(acpi_acquire_global_lock);
 778
 779 /*******************************************************************************
 780  *
 781  * FUNCTION:    acpi_release_global_lock
 782  *
 783  * PARAMETERS:  Handle      - Returned from acpi_acquire_global_lock
 784  *
 785  * RETURN:      Status
 786  *
 787  * DESCRIPTION: Release the ACPI Global Lock. The handle must be valid.
 788  *
 789  ******************************************************************************/
 790
 791 acpi_status acpi_release_global_lock(u32 handle)
 792 {
 793         acpi_status status;
 794
 795         if (handle != acpi_gbl_global_lock_handle) {
 796                 return (AE_NOT_ACQUIRED);
 797         }
 798
 799         status = acpi_ev_release_global_lock();
 800         return (status);
 801 }
 802
 803 EXPORT_SYMBOL(acpi_release_global_lock);