drivers/acpi/acpica/evxface.c

   1 /******************************************************************************
   2  *
   3  * Module Name: evxface - External interfaces for ACPI events
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2008, Intel Corp.
   9  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions, and the following disclaimer,
  16  *    without modification.
  17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  18  *    substantially similar to the "NO WARRANTY" disclaimer below
  19  *    ("Disclaimer") and any redistribution must be conditioned upon
  20  *    including a substantially similar Disclaimer requirement for further
  21  *    binary redistribution.
  22  * 3. Neither the names of the above-listed copyright holders nor the names
  23  *    of any contributors may be used to endorse or promote products derived
  24  *    from this software without specific prior written permission.
  25  *
  26  * Alternatively, this software may be distributed under the terms of the
  27  * GNU General Public License ("GPL") version 2 as published by the Free
  28  * Software Foundation.
  29  *
  30  * NO WARRANTY
  31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  41  * POSSIBILITY OF SUCH DAMAGES.
  42  */
  43
  44 #include <acpi/acpi.h>
  45 #include "accommon.h"
  46 #include "acnamesp.h"
  47 #include "acevents.h"
  48 #include "acinterp.h"
  49
  50 #define _COMPONENT          ACPI_EVENTS
  51 ACPI_MODULE_NAME("evxface")
  52
  53 /*******************************************************************************
  54  *
  55  * FUNCTION:    acpi_install_exception_handler
  56  *
  57  * PARAMETERS:  Handler         - Pointer to the handler function for the
  58  *                                event
  59  *
  60  * RETURN:      Status
  61  *
  62  * DESCRIPTION: Saves the pointer to the handler function
  63  *
  64  ******************************************************************************/
  65 #ifdef ACPI_FUTURE_USAGE
  66 acpi_status acpi_install_exception_handler(acpi_exception_handler handler)
  67 {
  68         acpi_status status;
  69
  70         ACPI_FUNCTION_TRACE(acpi_install_exception_handler);
  71
  72         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
  73         if (ACPI_FAILURE(status)) {
  74                 return_ACPI_STATUS(status);
  75         }
  76
  77         /* Don't allow two handlers. */
  78
  79         if (acpi_gbl_exception_handler) {
  80                 status = AE_ALREADY_EXISTS;
  81                 goto cleanup;
  82         }
  83
  84         /* Install the handler */
  85
  86         acpi_gbl_exception_handler = handler;
  87
  88       cleanup:
  89         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
  90         return_ACPI_STATUS(status);
  91 }
  92
  93 ACPI_EXPORT_SYMBOL(acpi_install_exception_handler)
  94 #endif                          /*  ACPI_FUTURE_USAGE  */
  95 /*******************************************************************************
  96  *
  97  * FUNCTION:    acpi_install_fixed_event_handler
  98  *
  99  * PARAMETERS:  Event           - Event type to enable.
 100  *              Handler         - Pointer to the handler function for the
 101  *                                event
 102  *              Context         - Value passed to the handler on each GPE
 103  *
 104  * RETURN:      Status
 105  *
 106  * DESCRIPTION: Saves the pointer to the handler function and then enables the
 107  *              event.
 108  *
 109  ******************************************************************************/
 110 acpi_status
 111 acpi_install_fixed_event_handler(u32 event,
 112                                  acpi_event_handler handler, void *context)
 113 {
 114         acpi_status status;
 115
 116         ACPI_FUNCTION_TRACE(acpi_install_fixed_event_handler);
 117
 118         /* Parameter validation */
 119
 120         if (event > ACPI_EVENT_MAX) {
 121                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 122         }
 123
 124         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 125         if (ACPI_FAILURE(status)) {
 126                 return_ACPI_STATUS(status);
 127         }
 128
 129         /* Don't allow two handlers. */
 130
 131         if (NULL != acpi_gbl_fixed_event_handlers[event].handler) {
 132                 status = AE_ALREADY_EXISTS;
 133                 goto cleanup;
 134         }
 135
 136         /* Install the handler before enabling the event */
 137
 138         acpi_gbl_fixed_event_handlers[event].handler = handler;
 139         acpi_gbl_fixed_event_handlers[event].context = context;
 140
 141         status = acpi_clear_event(event);
 142         if (ACPI_SUCCESS(status))
 143                 status = acpi_enable_event(event, 0);
 144         if (ACPI_FAILURE(status)) {
 145                 ACPI_WARNING((AE_INFO, "Could not enable fixed event %X",
 146                               event));
 147
 148                 /* Remove the handler */
 149
 150                 acpi_gbl_fixed_event_handlers[event].handler = NULL;
 151                 acpi_gbl_fixed_event_handlers[event].context = NULL;
 152         } else {
 153                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 154                                   "Enabled fixed event %X, Handler=%p\n", event,
 155                                   handler));
 156         }
 157
 158       cleanup:
 159         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 160         return_ACPI_STATUS(status);
 161 }
 162
 163 ACPI_EXPORT_SYMBOL(acpi_install_fixed_event_handler)
 164
 165 /*******************************************************************************
 166  *
 167  * FUNCTION:    acpi_remove_fixed_event_handler
 168  *
 169  * PARAMETERS:  Event           - Event type to disable.
 170  *              Handler         - Address of the handler
 171  *
 172  * RETURN:      Status
 173  *
 174  * DESCRIPTION: Disables the event and unregisters the event handler.
 175  *
 176  ******************************************************************************/
 177 acpi_status
 178 acpi_remove_fixed_event_handler(u32 event, acpi_event_handler handler)
 179 {
 180         acpi_status status = AE_OK;
 181
 182         ACPI_FUNCTION_TRACE(acpi_remove_fixed_event_handler);
 183
 184         /* Parameter validation */
 185
 186         if (event > ACPI_EVENT_MAX) {
 187                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 188         }
 189
 190         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 191         if (ACPI_FAILURE(status)) {
 192                 return_ACPI_STATUS(status);
 193         }
 194
 195         /* Disable the event before removing the handler */
 196
 197         status = acpi_disable_event(event, 0);
 198
 199         /* Always Remove the handler */
 200
 201         acpi_gbl_fixed_event_handlers[event].handler = NULL;
 202         acpi_gbl_fixed_event_handlers[event].context = NULL;
 203
 204         if (ACPI_FAILURE(status)) {
 205                 ACPI_WARNING((AE_INFO,
 206                               "Could not write to fixed event enable register %X",
 207                               event));
 208         } else {
 209                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Disabled fixed event %X\n",
 210                                   event));
 211         }
 212
 213         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 214         return_ACPI_STATUS(status);
 215 }
 216
 217 ACPI_EXPORT_SYMBOL(acpi_remove_fixed_event_handler)
 218
 219 /*******************************************************************************
 220  *
 221  * FUNCTION:    acpi_install_notify_handler
 222  *
 223  * PARAMETERS:  Device          - The device for which notifies will be handled
 224  *              handler_type    - The type of handler:
 225  *                                  ACPI_SYSTEM_NOTIFY: system_handler (00-7f)
 226  *                                  ACPI_DEVICE_NOTIFY: driver_handler (80-ff)
 227  *                                  ACPI_ALL_NOTIFY:  both system and device
 228  *              Handler         - Address of the handler
 229  *              Context         - Value passed to the handler on each GPE
 230  *
 231  * RETURN:      Status
 232  *
 233  * DESCRIPTION: Install a handler for notifies on an ACPI device
 234  *
 235  ******************************************************************************/
 236 acpi_status
 237 acpi_install_notify_handler(acpi_handle device,
 238                             u32 handler_type,
 239                             acpi_notify_handler handler, void *context)
 240 {
 241         union acpi_operand_object *obj_desc;
 242         union acpi_operand_object *notify_obj;
 243         struct acpi_namespace_node *node;
 244         acpi_status status;
 245
 246         ACPI_FUNCTION_TRACE(acpi_install_notify_handler);
 247
 248         /* Parameter validation */
 249
 250         if ((!device) ||
 251             (!handler) || (handler_type > ACPI_MAX_NOTIFY_HANDLER_TYPE)) {
 252                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 253         }
 254
 255         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 256         if (ACPI_FAILURE(status)) {
 257                 return_ACPI_STATUS(status);
 258         }
 259
 260         /* Convert and validate the device handle */
 261
 262         node = acpi_ns_map_handle_to_node(device);
 263         if (!node) {
 264                 status = AE_BAD_PARAMETER;
 265                 goto unlock_and_exit;
 266         }
 267
 268         /*
 269          * Root Object:
 270          * Registering a notify handler on the root object indicates that the
 271          * caller wishes to receive notifications for all objects. Note that
 272          * only one <external> global handler can be regsitered (per notify type).
 273          */
 274         if (device == ACPI_ROOT_OBJECT) {
 275
 276                 /* Make sure the handler is not already installed */
 277
 278                 if (((handler_type & ACPI_SYSTEM_NOTIFY) &&
 279                      acpi_gbl_system_notify.handler) ||
 280                     ((handler_type & ACPI_DEVICE_NOTIFY) &&
 281                      acpi_gbl_device_notify.handler)) {
 282                         status = AE_ALREADY_EXISTS;
 283                         goto unlock_and_exit;
 284                 }
 285
 286                 if (handler_type & ACPI_SYSTEM_NOTIFY) {
 287                         acpi_gbl_system_notify.node = node;
 288                         acpi_gbl_system_notify.handler = handler;
 289                         acpi_gbl_system_notify.context = context;
 290                 }
 291
 292                 if (handler_type & ACPI_DEVICE_NOTIFY) {
 293                         acpi_gbl_device_notify.node = node;
 294                         acpi_gbl_device_notify.handler = handler;
 295                         acpi_gbl_device_notify.context = context;
 296                 }
 297
 298                 /* Global notify handler installed */
 299         }
 300
 301         /*
 302          * All Other Objects:
 303          * Caller will only receive notifications specific to the target object.
 304          * Note that only certain object types can receive notifications.
 305          */
 306         else {
 307                 /* Notifies allowed on this object? */
 308
 309                 if (!acpi_ev_is_notify_object(node)) {
 310                         status = AE_TYPE;
 311                         goto unlock_and_exit;
 312                 }
 313
 314                 /* Check for an existing internal object */
 315
 316                 obj_desc = acpi_ns_get_attached_object(node);
 317                 if (obj_desc) {
 318
 319                         /* Object exists - make sure there's no handler */
 320
 321                         if (((handler_type & ACPI_SYSTEM_NOTIFY) &&
 322                              obj_desc->common_notify.system_notify) ||
 323                             ((handler_type & ACPI_DEVICE_NOTIFY) &&
 324                              obj_desc->common_notify.device_notify)) {
 325                                 status = AE_ALREADY_EXISTS;
 326                                 goto unlock_and_exit;
 327                         }
 328                 } else {
 329                         /* Create a new object */
 330
 331                         obj_desc = acpi_ut_create_internal_object(node->type);
 332                         if (!obj_desc) {
 333                                 status = AE_NO_MEMORY;
 334                                 goto unlock_and_exit;
 335                         }
 336
 337                         /* Attach new object to the Node */
 338
 339                         status =
 340                             acpi_ns_attach_object(device, obj_desc, node->type);
 341
 342                         /* Remove local reference to the object */
 343
 344                         acpi_ut_remove_reference(obj_desc);
 345                         if (ACPI_FAILURE(status)) {
 346                                 goto unlock_and_exit;
 347                         }
 348                 }
 349
 350                 /* Install the handler */
 351
 352                 notify_obj =
 353                     acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_NOTIFY);
 354                 if (!notify_obj) {
 355                         status = AE_NO_MEMORY;
 356                         goto unlock_and_exit;
 357                 }
 358
 359                 notify_obj->notify.node = node;
 360                 notify_obj->notify.handler = handler;
 361                 notify_obj->notify.context = context;
 362
 363                 if (handler_type & ACPI_SYSTEM_NOTIFY) {
 364                         obj_desc->common_notify.system_notify = notify_obj;
 365                 }
 366
 367                 if (handler_type & ACPI_DEVICE_NOTIFY) {
 368                         obj_desc->common_notify.device_notify = notify_obj;
 369                 }
 370
 371                 if (handler_type == ACPI_ALL_NOTIFY) {
 372
 373                         /* Extra ref if installed in both */
 374
 375                         acpi_ut_add_reference(notify_obj);
 376                 }
 377         }
 378
 379       unlock_and_exit:
 380         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 381         return_ACPI_STATUS(status);
 382 }
 383
 384 ACPI_EXPORT_SYMBOL(acpi_install_notify_handler)
 385
 386 /*******************************************************************************
 387  *
 388  * FUNCTION:    acpi_remove_notify_handler
 389  *
 390  * PARAMETERS:  Device          - The device for which notifies will be handled
 391  *              handler_type    - The type of handler:
 392  *                                  ACPI_SYSTEM_NOTIFY: system_handler (00-7f)
 393  *                                  ACPI_DEVICE_NOTIFY: driver_handler (80-ff)
 394  *                                  ACPI_ALL_NOTIFY:  both system and device
 395  *              Handler         - Address of the handler
 396  *
 397  * RETURN:      Status
 398  *
 399  * DESCRIPTION: Remove a handler for notifies on an ACPI device
 400  *
 401  ******************************************************************************/
 402 acpi_status
 403 acpi_remove_notify_handler(acpi_handle device,
 404                            u32 handler_type, acpi_notify_handler handler)
 405 {
 406         union acpi_operand_object *notify_obj;
 407         union acpi_operand_object *obj_desc;
 408         struct acpi_namespace_node *node;
 409         acpi_status status;
 410
 411         ACPI_FUNCTION_TRACE(acpi_remove_notify_handler);
 412
 413         /* Parameter validation */
 414
 415         if ((!device) ||
 416             (!handler) || (handler_type > ACPI_MAX_NOTIFY_HANDLER_TYPE)) {
 417                 status = AE_BAD_PARAMETER;
 418                 goto exit;
 419         }
 420
 421         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 422         if (ACPI_FAILURE(status)) {
 423                 goto exit;
 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                         goto exit;
 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                                 status = AE_NOT_EXIST;
 494                                 goto unlock_and_exit;
 495                         }
 496
 497                         if (notify_obj->notify.handler != handler) {
 498                                 status = AE_BAD_PARAMETER;
 499                                 goto unlock_and_exit;
 500                         }
 501                         /* Make sure all deferred tasks are completed */
 502
 503                         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 504                         acpi_os_wait_events_complete(NULL);
 505                         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 506                         if (ACPI_FAILURE(status)) {
 507                                 goto exit;
 508                         }
 509
 510                         /* Remove the handler */
 511                         obj_desc->common_notify.system_notify = NULL;
 512                         acpi_ut_remove_reference(notify_obj);
 513                 }
 514
 515                 if (handler_type & ACPI_DEVICE_NOTIFY) {
 516                         notify_obj = obj_desc->common_notify.device_notify;
 517                         if (!notify_obj) {
 518                                 status = AE_NOT_EXIST;
 519                                 goto unlock_and_exit;
 520                         }
 521
 522                         if (notify_obj->notify.handler != handler) {
 523                                 status = AE_BAD_PARAMETER;
 524                                 goto unlock_and_exit;
 525                         }
 526                         /* Make sure all deferred tasks are completed */
 527
 528                         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 529                         acpi_os_wait_events_complete(NULL);
 530                         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 531                         if (ACPI_FAILURE(status)) {
 532                                 goto exit;
 533                         }
 534
 535                         /* Remove the handler */
 536                         obj_desc->common_notify.device_notify = NULL;
 537                         acpi_ut_remove_reference(notify_obj);
 538                 }
 539         }
 540
 541       unlock_and_exit:
 542         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 543       exit:
 544         if (ACPI_FAILURE(status))
 545                 ACPI_EXCEPTION((AE_INFO, status, "Removing notify handler"));
 546         return_ACPI_STATUS(status);
 547 }
 548
 549 ACPI_EXPORT_SYMBOL(acpi_remove_notify_handler)
 550
 551 /*******************************************************************************
 552  *
 553  * FUNCTION:    acpi_install_gpe_handler
 554  *
 555  * PARAMETERS:  gpe_device      - Namespace node for the GPE (NULL for FADT
 556  *                                defined GPEs)
 557  *              gpe_number      - The GPE number within the GPE block
 558  *              Type            - Whether this GPE should be treated as an
 559  *                                edge- or level-triggered interrupt.
 560  *              Address         - Address of the handler
 561  *              Context         - Value passed to the handler on each GPE
 562  *
 563  * RETURN:      Status
 564  *
 565  * DESCRIPTION: Install a handler for a General Purpose Event.
 566  *
 567  ******************************************************************************/
 568 acpi_status
 569 acpi_install_gpe_handler(acpi_handle gpe_device,
 570                          u32 gpe_number,
 571                          u32 type, acpi_event_handler address, void *context)
 572 {
 573         struct acpi_gpe_event_info *gpe_event_info;
 574         struct acpi_handler_info *handler;
 575         acpi_status status;
 576         acpi_cpu_flags flags;
 577
 578         ACPI_FUNCTION_TRACE(acpi_install_gpe_handler);
 579
 580         /* Parameter validation */
 581
 582         if ((!address) || (type > ACPI_GPE_XRUPT_TYPE_MASK)) {
 583                 status = AE_BAD_PARAMETER;
 584                 goto exit;
 585         }
 586
 587         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 588         if (ACPI_FAILURE(status)) {
 589                 goto exit;
 590         }
 591
 592         /* Ensure that we have a valid GPE number */
 593
 594         gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
 595         if (!gpe_event_info) {
 596                 status = AE_BAD_PARAMETER;
 597                 goto unlock_and_exit;
 598         }
 599
 600         /* Make sure that there isn't a handler there already */
 601
 602         if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
 603             ACPI_GPE_DISPATCH_HANDLER) {
 604                 status = AE_ALREADY_EXISTS;
 605                 goto unlock_and_exit;
 606         }
 607
 608         /* Allocate and init handler object */
 609
 610         handler = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_handler_info));
 611         if (!handler) {
 612                 status = AE_NO_MEMORY;
 613                 goto unlock_and_exit;
 614         }
 615
 616         handler->address = address;
 617         handler->context = context;
 618         handler->method_node = gpe_event_info->dispatch.method_node;
 619
 620         /* Disable the GPE before installing the handler */
 621
 622         status = acpi_ev_disable_gpe(gpe_event_info);
 623         if (ACPI_FAILURE(status)) {
 624                 goto unlock_and_exit;
 625         }
 626
 627         /* Install the handler */
 628
 629         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 630         gpe_event_info->dispatch.handler = handler;
 631
 632         /* Setup up dispatch flags to indicate handler (vs. method) */
 633
 634         gpe_event_info->flags &=
 635             ~(ACPI_GPE_XRUPT_TYPE_MASK | ACPI_GPE_DISPATCH_MASK);
 636         gpe_event_info->flags |= (u8) (type | ACPI_GPE_DISPATCH_HANDLER);
 637
 638         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 639
 640       unlock_and_exit:
 641         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 642       exit:
 643         if (ACPI_FAILURE(status))
 644                 ACPI_EXCEPTION((AE_INFO, status,
 645                                 "Installing notify handler failed"));
 646         return_ACPI_STATUS(status);
 647 }
 648
 649 ACPI_EXPORT_SYMBOL(acpi_install_gpe_handler)
 650
 651 /*******************************************************************************
 652  *
 653  * FUNCTION:    acpi_remove_gpe_handler
 654  *
 655  * PARAMETERS:  gpe_device      - Namespace node for the GPE (NULL for FADT
 656  *                                defined GPEs)
 657  *              gpe_number      - The event to remove a handler
 658  *              Address         - Address of the handler
 659  *
 660  * RETURN:      Status
 661  *
 662  * DESCRIPTION: Remove a handler for a General Purpose acpi_event.
 663  *
 664  ******************************************************************************/
 665 acpi_status
 666 acpi_remove_gpe_handler(acpi_handle gpe_device,
 667                         u32 gpe_number, acpi_event_handler address)
 668 {
 669         struct acpi_gpe_event_info *gpe_event_info;
 670         struct acpi_handler_info *handler;
 671         acpi_status status;
 672         acpi_cpu_flags flags;
 673
 674         ACPI_FUNCTION_TRACE(acpi_remove_gpe_handler);
 675
 676         /* Parameter validation */
 677
 678         if (!address) {
 679                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 680         }
 681
 682         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 683         if (ACPI_FAILURE(status)) {
 684                 return_ACPI_STATUS(status);
 685         }
 686
 687         /* Ensure that we have a valid GPE number */
 688
 689         gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
 690         if (!gpe_event_info) {
 691                 status = AE_BAD_PARAMETER;
 692                 goto unlock_and_exit;
 693         }
 694
 695         /* Make sure that a handler is indeed installed */
 696
 697         if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) !=
 698             ACPI_GPE_DISPATCH_HANDLER) {
 699                 status = AE_NOT_EXIST;
 700                 goto unlock_and_exit;
 701         }
 702
 703         /* Make sure that the installed handler is the same */
 704
 705         if (gpe_event_info->dispatch.handler->address != address) {
 706                 status = AE_BAD_PARAMETER;
 707                 goto unlock_and_exit;
 708         }
 709
 710         /* Disable the GPE before removing the handler */
 711
 712         status = acpi_ev_disable_gpe(gpe_event_info);
 713         if (ACPI_FAILURE(status)) {
 714                 goto unlock_and_exit;
 715         }
 716
 717         /* Make sure all deferred tasks are completed */
 718
 719         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 720         acpi_os_wait_events_complete(NULL);
 721         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 722         if (ACPI_FAILURE(status)) {
 723                 return_ACPI_STATUS(status);
 724         }
 725
 726         /* Remove the handler */
 727
 728         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 729         handler = gpe_event_info->dispatch.handler;
 730
 731         /* Restore Method node (if any), set dispatch flags */
 732
 733         gpe_event_info->dispatch.method_node = handler->method_node;
 734         gpe_event_info->flags &= ~ACPI_GPE_DISPATCH_MASK;       /* Clear bits */
 735         if (handler->method_node) {
 736                 gpe_event_info->flags |= ACPI_GPE_DISPATCH_METHOD;
 737         }
 738         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 739
 740         /* Now we can free the handler object */
 741
 742         ACPI_FREE(handler);
 743
 744       unlock_and_exit:
 745         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 746         return_ACPI_STATUS(status);
 747 }
 748
 749 ACPI_EXPORT_SYMBOL(acpi_remove_gpe_handler)
 750
 751 /*******************************************************************************
 752  *
 753  * FUNCTION:    acpi_acquire_global_lock
 754  *
 755  * PARAMETERS:  Timeout         - How long the caller is willing to wait
 756  *              Handle          - Where the handle to the lock is returned
 757  *                                (if acquired)
 758  *
 759  * RETURN:      Status
 760  *
 761  * DESCRIPTION: Acquire the ACPI Global Lock
 762  *
 763  * Note: Allows callers with the same thread ID to acquire the global lock
 764  * multiple times. In other words, externally, the behavior of the global lock
 765  * is identical to an AML mutex. On the first acquire, a new handle is
 766  * returned. On any subsequent calls to acquire by the same thread, the same
 767  * handle is returned.
 768  *
 769  ******************************************************************************/
 770 acpi_status acpi_acquire_global_lock(u16 timeout, u32 * handle)
 771 {
 772         acpi_status status;
 773
 774         if (!handle) {
 775                 return (AE_BAD_PARAMETER);
 776         }
 777
 778         /* Must lock interpreter to prevent race conditions */
 779
 780         acpi_ex_enter_interpreter();
 781
 782         status = acpi_ex_acquire_mutex_object(timeout,
 783                                               acpi_gbl_global_lock_mutex,
 784                                               acpi_os_get_thread_id());
 785
 786         if (ACPI_SUCCESS(status)) {
 787
 788                 /* Return the global lock handle (updated in acpi_ev_acquire_global_lock) */
 789
 790                 *handle = acpi_gbl_global_lock_handle;
 791         }
 792
 793         acpi_ex_exit_interpreter();
 794         return (status);
 795 }
 796
 797 ACPI_EXPORT_SYMBOL(acpi_acquire_global_lock)
 798
 799 /*******************************************************************************
 800  *
 801  * FUNCTION:    acpi_release_global_lock
 802  *
 803  * PARAMETERS:  Handle      - Returned from acpi_acquire_global_lock
 804  *
 805  * RETURN:      Status
 806  *
 807  * DESCRIPTION: Release the ACPI Global Lock. The handle must be valid.
 808  *
 809  ******************************************************************************/
 810 acpi_status acpi_release_global_lock(u32 handle)
 811 {
 812         acpi_status status;
 813
 814         if (!handle || (handle != acpi_gbl_global_lock_handle)) {
 815                 return (AE_NOT_ACQUIRED);
 816         }
 817
 818         status = acpi_ex_release_mutex_object(acpi_gbl_global_lock_mutex);
 819         return (status);
 820 }
 821
 822 ACPI_EXPORT_SYMBOL(acpi_release_global_lock)