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_REPORT_WARNING(("Could not enable fixed event %X\n",
 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_REPORT_WARNING(("Could not write to fixed event enable register %X\n", 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 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
 237 acpi_status
 238 acpi_install_notify_handler(acpi_handle device,
 239                             u32 handler_type,
 240                             acpi_notify_handler handler, void *context)
 241 {
 242         union acpi_operand_object *obj_desc;
 243         union acpi_operand_object *notify_obj;
 244         struct acpi_namespace_node *node;
 245         acpi_status status;
 246
 247         ACPI_FUNCTION_TRACE("acpi_install_notify_handler");
 248
 249         /* Parameter validation */
 250
 251         if ((!device) ||
 252             (!handler) || (handler_type > ACPI_MAX_NOTIFY_HANDLER_TYPE)) {
 253                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 254         }
 255
 256         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 257         if (ACPI_FAILURE(status)) {
 258                 return_ACPI_STATUS(status);
 259         }
 260
 261         /* Convert and validate the device handle */
 262
 263         node = acpi_ns_map_handle_to_node(device);
 264         if (!node) {
 265                 status = AE_BAD_PARAMETER;
 266                 goto unlock_and_exit;
 267         }
 268
 269         /*
 270          * Root Object:
 271          * Registering a notify handler on the root object indicates that the
 272          * caller wishes to receive notifications for all objects.  Note that
 273          * only one <external> global handler can be regsitered (per notify type).
 274          */
 275         if (device == ACPI_ROOT_OBJECT) {
 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                         /* Object exists - make sure there's no handler */
 319
 320                         if (((handler_type & ACPI_SYSTEM_NOTIFY) &&
 321                              obj_desc->common_notify.system_notify) ||
 322                             ((handler_type & ACPI_DEVICE_NOTIFY) &&
 323                              obj_desc->common_notify.device_notify)) {
 324                                 status = AE_ALREADY_EXISTS;
 325                                 goto unlock_and_exit;
 326                         }
 327                 } else {
 328                         /* Create a new object */
 329
 330                         obj_desc = acpi_ut_create_internal_object(node->type);
 331                         if (!obj_desc) {
 332                                 status = AE_NO_MEMORY;
 333                                 goto unlock_and_exit;
 334                         }
 335
 336                         /* Attach new object to the Node */
 337
 338                         status =
 339                             acpi_ns_attach_object(device, obj_desc, node->type);
 340
 341                         /* Remove local reference to the object */
 342
 343                         acpi_ut_remove_reference(obj_desc);
 344                         if (ACPI_FAILURE(status)) {
 345                                 goto unlock_and_exit;
 346                         }
 347                 }
 348
 349                 /* Install the handler */
 350
 351                 notify_obj =
 352                     acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_NOTIFY);
 353                 if (!notify_obj) {
 354                         status = AE_NO_MEMORY;
 355                         goto unlock_and_exit;
 356                 }
 357
 358                 notify_obj->notify.node = node;
 359                 notify_obj->notify.handler = handler;
 360                 notify_obj->notify.context = context;
 361
 362                 if (handler_type & ACPI_SYSTEM_NOTIFY) {
 363                         obj_desc->common_notify.system_notify = notify_obj;
 364                 }
 365
 366                 if (handler_type & ACPI_DEVICE_NOTIFY) {
 367                         obj_desc->common_notify.device_notify = notify_obj;
 368                 }
 369
 370                 if (handler_type == ACPI_ALL_NOTIFY) {
 371                         /* Extra ref if installed in both */
 372
 373                         acpi_ut_add_reference(notify_obj);
 374                 }
 375         }
 376
 377       unlock_and_exit:
 378         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 379         return_ACPI_STATUS(status);
 380 }
 381
 382 EXPORT_SYMBOL(acpi_install_notify_handler);
 383
 384 /*******************************************************************************
 385  *
 386  * FUNCTION:    acpi_remove_notify_handler
 387  *
 388  * PARAMETERS:  Device          - The device for which notifies will be handled
 389  *              handler_type    - The type of handler:
 390  *                                  ACPI_SYSTEM_NOTIFY: system_handler (00-7f)
 391  *                                  ACPI_DEVICE_NOTIFY: driver_handler (80-ff)
 392  *                                  ACPI_ALL_NOTIFY:  both system and device
 393  *              Handler         - Address of the handler
 394  *
 395  * RETURN:      Status
 396  *
 397  * DESCRIPTION: Remove a handler for notifies on an ACPI device
 398  *
 399  ******************************************************************************/
 400
 401 acpi_status
 402 acpi_remove_notify_handler(acpi_handle device,
 403                            u32 handler_type, acpi_notify_handler handler)
 404 {
 405         union acpi_operand_object *notify_obj;
 406         union acpi_operand_object *obj_desc;
 407         struct acpi_namespace_node *node;
 408         acpi_status status;
 409
 410         ACPI_FUNCTION_TRACE("acpi_remove_notify_handler");
 411
 412         /* Parameter validation */
 413
 414         if ((!device) ||
 415             (!handler) || (handler_type > ACPI_MAX_NOTIFY_HANDLER_TYPE)) {
 416                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 417         }
 418
 419         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 420         if (ACPI_FAILURE(status)) {
 421                 return_ACPI_STATUS(status);
 422         }
 423
 424         /* Convert and validate the device handle */
 425
 426         node = acpi_ns_map_handle_to_node(device);
 427         if (!node) {
 428                 status = AE_BAD_PARAMETER;
 429                 goto unlock_and_exit;
 430         }
 431
 432         /* Root Object */
 433
 434         if (device == ACPI_ROOT_OBJECT) {
 435                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 436                                   "Removing notify handler for namespace root object\n"));
 437
 438                 if (((handler_type & ACPI_SYSTEM_NOTIFY) &&
 439                      !acpi_gbl_system_notify.handler) ||
 440                     ((handler_type & ACPI_DEVICE_NOTIFY) &&
 441                      !acpi_gbl_device_notify.handler)) {
 442                         status = AE_NOT_EXIST;
 443                         goto unlock_and_exit;
 444                 }
 445
 446                 /* Make sure all deferred tasks are completed */
 447
 448                 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 449                 acpi_os_wait_events_complete(NULL);
 450                 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 451                 if (ACPI_FAILURE(status)) {
 452                         return_ACPI_STATUS(status);
 453                 }
 454
 455                 if (handler_type & ACPI_SYSTEM_NOTIFY) {
 456                         acpi_gbl_system_notify.node = NULL;
 457                         acpi_gbl_system_notify.handler = NULL;
 458                         acpi_gbl_system_notify.context = NULL;
 459                 }
 460
 461                 if (handler_type & ACPI_DEVICE_NOTIFY) {
 462                         acpi_gbl_device_notify.node = NULL;
 463                         acpi_gbl_device_notify.handler = NULL;
 464                         acpi_gbl_device_notify.context = NULL;
 465                 }
 466         }
 467
 468         /* All Other Objects */
 469
 470         else {
 471                 /* Notifies allowed on this object? */
 472
 473                 if (!acpi_ev_is_notify_object(node)) {
 474                         status = AE_TYPE;
 475                         goto unlock_and_exit;
 476                 }
 477
 478                 /* Check for an existing internal object */
 479
 480                 obj_desc = acpi_ns_get_attached_object(node);
 481                 if (!obj_desc) {
 482                         status = AE_NOT_EXIST;
 483                         goto unlock_and_exit;
 484                 }
 485
 486                 /* Object exists - make sure there's an existing handler */
 487
 488                 if (handler_type & ACPI_SYSTEM_NOTIFY) {
 489                         notify_obj = obj_desc->common_notify.system_notify;
 490                         if ((!notify_obj) ||
 491                             (notify_obj->notify.handler != handler)) {
 492                                 status = AE_BAD_PARAMETER;
 493                                 goto unlock_and_exit;
 494                         }
 495                         /* Make sure all deferred tasks are completed */
 496
 497                         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 498                         acpi_os_wait_events_complete(NULL);
 499                         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 500                         if (ACPI_FAILURE(status)) {
 501                                 return_ACPI_STATUS(status);
 502                         }
 503
 504                         /* Remove the handler */
 505                         obj_desc->common_notify.system_notify = NULL;
 506                         acpi_ut_remove_reference(notify_obj);
 507                 }
 508
 509                 if (handler_type & ACPI_DEVICE_NOTIFY) {
 510                         notify_obj = obj_desc->common_notify.device_notify;
 511                         if ((!notify_obj) ||
 512                             (notify_obj->notify.handler != handler)) {
 513                                 status = AE_BAD_PARAMETER;
 514                                 goto unlock_and_exit;
 515                         }
 516                         /* Make sure all deferred tasks are completed */
 517
 518                         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 519                         acpi_os_wait_events_complete(NULL);
 520                         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 521                         if (ACPI_FAILURE(status)) {
 522                                 return_ACPI_STATUS(status);
 523                         }
 524
 525                         /* Remove the handler */
 526                         obj_desc->common_notify.device_notify = NULL;
 527                         acpi_ut_remove_reference(notify_obj);
 528                 }
 529         }
 530
 531       unlock_and_exit:
 532         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 533         return_ACPI_STATUS(status);
 534 }
 535
 536 EXPORT_SYMBOL(acpi_remove_notify_handler);
 537
 538 /*******************************************************************************
 539  *
 540  * FUNCTION:    acpi_install_gpe_handler
 541  *
 542  * PARAMETERS:  gpe_device      - Namespace node for the GPE (NULL for FADT
 543  *                                defined GPEs)
 544  *              gpe_number      - The GPE number within the GPE block
 545  *              Type            - Whether this GPE should be treated as an
 546  *                                edge- or level-triggered interrupt.
 547  *              Address         - Address of the handler
 548  *              Context         - Value passed to the handler on each GPE
 549  *
 550  * RETURN:      Status
 551  *
 552  * DESCRIPTION: Install a handler for a General Purpose Event.
 553  *
 554  ******************************************************************************/
 555
 556 acpi_status
 557 acpi_install_gpe_handler(acpi_handle gpe_device,
 558                          u32 gpe_number,
 559                          u32 type, acpi_event_handler address, void *context)
 560 {
 561         struct acpi_gpe_event_info *gpe_event_info;
 562         struct acpi_handler_info *handler;
 563         acpi_status status;
 564         acpi_native_uint flags;
 565
 566         ACPI_FUNCTION_TRACE("acpi_install_gpe_handler");
 567
 568         /* Parameter validation */
 569
 570         if ((!address) || (type > ACPI_GPE_XRUPT_TYPE_MASK)) {
 571                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 572         }
 573
 574         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 575         if (ACPI_FAILURE(status)) {
 576                 return_ACPI_STATUS(status);
 577         }
 578
 579         /* Ensure that we have a valid GPE number */
 580
 581         gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
 582         if (!gpe_event_info) {
 583                 status = AE_BAD_PARAMETER;
 584                 goto unlock_and_exit;
 585         }
 586
 587         /* Make sure that there isn't a handler there already */
 588
 589         if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
 590             ACPI_GPE_DISPATCH_HANDLER) {
 591                 status = AE_ALREADY_EXISTS;
 592                 goto unlock_and_exit;
 593         }
 594
 595         /* Allocate and init handler object */
 596
 597         handler = ACPI_MEM_CALLOCATE(sizeof(struct acpi_handler_info));
 598         if (!handler) {
 599                 status = AE_NO_MEMORY;
 600                 goto unlock_and_exit;
 601         }
 602
 603         handler->address = address;
 604         handler->context = context;
 605         handler->method_node = gpe_event_info->dispatch.method_node;
 606
 607         /* Disable the GPE before installing the handler */
 608
 609         status = acpi_ev_disable_gpe(gpe_event_info);
 610         if (ACPI_FAILURE(status)) {
 611                 goto unlock_and_exit;
 612         }
 613
 614         /* Install the handler */
 615
 616         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 617         gpe_event_info->dispatch.handler = handler;
 618
 619         /* Setup up dispatch flags to indicate handler (vs. method) */
 620
 621         gpe_event_info->flags &= ~(ACPI_GPE_XRUPT_TYPE_MASK | ACPI_GPE_DISPATCH_MASK);  /* Clear bits */
 622         gpe_event_info->flags |= (u8) (type | ACPI_GPE_DISPATCH_HANDLER);
 623
 624         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 625
 626       unlock_and_exit:
 627         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 628         return_ACPI_STATUS(status);
 629 }
 630
 631 EXPORT_SYMBOL(acpi_install_gpe_handler);
 632
 633 /*******************************************************************************
 634  *
 635  * FUNCTION:    acpi_remove_gpe_handler
 636  *
 637  * PARAMETERS:  gpe_device      - Namespace node for the GPE (NULL for FADT
 638  *                                defined GPEs)
 639  *              gpe_number      - The event to remove a handler
 640  *              Address         - Address of the handler
 641  *
 642  * RETURN:      Status
 643  *
 644  * DESCRIPTION: Remove a handler for a General Purpose acpi_event.
 645  *
 646  ******************************************************************************/
 647
 648 acpi_status
 649 acpi_remove_gpe_handler(acpi_handle gpe_device,
 650                         u32 gpe_number, acpi_event_handler address)
 651 {
 652         struct acpi_gpe_event_info *gpe_event_info;
 653         struct acpi_handler_info *handler;
 654         acpi_status status;
 655         acpi_native_uint flags;
 656
 657         ACPI_FUNCTION_TRACE("acpi_remove_gpe_handler");
 658
 659         /* Parameter validation */
 660
 661         if (!address) {
 662                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 663         }
 664
 665         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 666         if (ACPI_FAILURE(status)) {
 667                 return_ACPI_STATUS(status);
 668         }
 669
 670         /* Ensure that we have a valid GPE number */
 671
 672         gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
 673         if (!gpe_event_info) {
 674                 status = AE_BAD_PARAMETER;
 675                 goto unlock_and_exit;
 676         }
 677
 678         /* Make sure that a handler is indeed installed */
 679
 680         if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) !=
 681             ACPI_GPE_DISPATCH_HANDLER) {
 682                 status = AE_NOT_EXIST;
 683                 goto unlock_and_exit;
 684         }
 685
 686         /* Make sure that the installed handler is the same */
 687
 688         if (gpe_event_info->dispatch.handler->address != address) {
 689                 status = AE_BAD_PARAMETER;
 690                 goto unlock_and_exit;
 691         }
 692
 693         /* Disable the GPE before removing the handler */
 694
 695         status = acpi_ev_disable_gpe(gpe_event_info);
 696         if (ACPI_FAILURE(status)) {
 697                 goto unlock_and_exit;
 698         }
 699
 700         /* Make sure all deferred tasks are completed */
 701
 702         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 703         acpi_os_wait_events_complete(NULL);
 704         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 705         if (ACPI_FAILURE(status)) {
 706                 return_ACPI_STATUS(status);
 707         }
 708
 709         /* Remove the handler */
 710
 711         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 712         handler = gpe_event_info->dispatch.handler;
 713
 714         /* Restore Method node (if any), set dispatch flags */
 715
 716         gpe_event_info->dispatch.method_node = handler->method_node;
 717         gpe_event_info->flags &= ~ACPI_GPE_DISPATCH_MASK;       /* Clear bits */
 718         if (handler->method_node) {
 719                 gpe_event_info->flags |= ACPI_GPE_DISPATCH_METHOD;
 720         }
 721         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 722
 723         /* Now we can free the handler object */
 724
 725         ACPI_MEM_FREE(handler);
 726
 727       unlock_and_exit:
 728         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 729         return_ACPI_STATUS(status);
 730 }
 731
 732 EXPORT_SYMBOL(acpi_remove_gpe_handler);
 733
 734 /*******************************************************************************
 735  *
 736  * FUNCTION:    acpi_acquire_global_lock
 737  *
 738  * PARAMETERS:  Timeout         - How long the caller is willing to wait
 739  *              Handle          - Where the handle to the lock is returned
 740  *                                (if acquired)
 741  *
 742  * RETURN:      Status
 743  *
 744  * DESCRIPTION: Acquire the ACPI Global Lock
 745  *
 746  ******************************************************************************/
 747
 748 acpi_status acpi_acquire_global_lock(u16 timeout, u32 * handle)
 749 {
 750         acpi_status status;
 751
 752         if (!handle) {
 753                 return (AE_BAD_PARAMETER);
 754         }
 755
 756         status = acpi_ex_enter_interpreter();
 757         if (ACPI_FAILURE(status)) {
 758                 return (status);
 759         }
 760
 761         status = acpi_ev_acquire_global_lock(timeout);
 762         acpi_ex_exit_interpreter();
 763
 764         if (ACPI_SUCCESS(status)) {
 765                 acpi_gbl_global_lock_handle++;
 766                 *handle = acpi_gbl_global_lock_handle;
 767         }
 768
 769         return (status);
 770 }
 771
 772 EXPORT_SYMBOL(acpi_acquire_global_lock);
 773
 774 /*******************************************************************************
 775  *
 776  * FUNCTION:    acpi_release_global_lock
 777  *
 778  * PARAMETERS:  Handle      - Returned from acpi_acquire_global_lock
 779  *
 780  * RETURN:      Status
 781  *
 782  * DESCRIPTION: Release the ACPI Global Lock. The handle must be valid.
 783  *
 784  ******************************************************************************/
 785
 786 acpi_status acpi_release_global_lock(u32 handle)
 787 {
 788         acpi_status status;
 789
 790         if (handle != acpi_gbl_global_lock_handle) {
 791                 return (AE_NOT_ACQUIRED);
 792         }
 793
 794         status = acpi_ev_release_global_lock();
 795         return (status);
 796 }
 797
 798 EXPORT_SYMBOL(acpi_release_global_lock);