drivers/acpi/acpica/evxface.c

   1 /******************************************************************************
   2  *
   3  * Module Name: evxface - External interfaces for ACPI events
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2013, 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 <linux/export.h>
  45 #include <acpi/acpi.h>
  46 #include "accommon.h"
  47 #include "acnamesp.h"
  48 #include "acevents.h"
  49 #include "acinterp.h"
  50
  51 #define _COMPONENT          ACPI_EVENTS
  52 ACPI_MODULE_NAME("evxface")
  53
  54
  55 /*******************************************************************************
  56  *
  57  * FUNCTION:    acpi_install_notify_handler
  58  *
  59  * PARAMETERS:  device          - The device for which notifies will be handled
  60  *              handler_type    - The type of handler:
  61  *                                  ACPI_SYSTEM_NOTIFY: System Handler (00-7F)
  62  *                                  ACPI_DEVICE_NOTIFY: Device Handler (80-FF)
  63  *                                  ACPI_ALL_NOTIFY:    Both System and Device
  64  *              handler         - Address of the handler
  65  *              context         - Value passed to the handler on each GPE
  66  *
  67  * RETURN:      Status
  68  *
  69  * DESCRIPTION: Install a handler for notifications on an ACPI Device,
  70  *              thermal_zone, or Processor object.
  71  *
  72  * NOTES:       The Root namespace object may have only one handler for each
  73  *              type of notify (System/Device). Device/Thermal/Processor objects
  74  *              may have one device notify handler, and multiple system notify
  75  *              handlers.
  76  *
  77  ******************************************************************************/
  78 acpi_status
  79 acpi_install_notify_handler(acpi_handle device,
  80                             u32 handler_type,
  81                             acpi_notify_handler handler, void *context)
  82 {
  83         struct acpi_namespace_node *node =
  84             ACPI_CAST_PTR(struct acpi_namespace_node, device);
  85         union acpi_operand_object *obj_desc;
  86         union acpi_operand_object *handler_obj;
  87         acpi_status status;
  88         u32 i;
  89
  90         ACPI_FUNCTION_TRACE(acpi_install_notify_handler);
  91
  92         /* Parameter validation */
  93
  94         if ((!device) || (!handler) || (!handler_type) ||
  95             (handler_type > ACPI_MAX_NOTIFY_HANDLER_TYPE)) {
  96                 return_ACPI_STATUS(AE_BAD_PARAMETER);
  97         }
  98
  99         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 100         if (ACPI_FAILURE(status)) {
 101                 return_ACPI_STATUS(status);
 102         }
 103
 104         /*
 105          * Root Object:
 106          * Registering a notify handler on the root object indicates that the
 107          * caller wishes to receive notifications for all objects. Note that
 108          * only one global handler can be registered per notify type.
 109          * Ensure that a handler is not already installed.
 110          */
 111         if (device == ACPI_ROOT_OBJECT) {
 112                 for (i = 0; i < ACPI_NUM_NOTIFY_TYPES; i++) {
 113                         if (handler_type & (i + 1)) {
 114                                 if (acpi_gbl_global_notify[i].handler) {
 115                                         status = AE_ALREADY_EXISTS;
 116                                         goto unlock_and_exit;
 117                                 }
 118
 119                                 acpi_gbl_global_notify[i].handler = handler;
 120                                 acpi_gbl_global_notify[i].context = context;
 121                         }
 122                 }
 123
 124                 goto unlock_and_exit;   /* Global notify handler installed, all done */
 125         }
 126
 127         /*
 128          * All Other Objects:
 129          * Caller will only receive notifications specific to the target
 130          * object. Note that only certain object types are allowed to
 131          * receive notifications.
 132          */
 133
 134         /* Are Notifies allowed on this object? */
 135
 136         if (!acpi_ev_is_notify_object(node)) {
 137                 status = AE_TYPE;
 138                 goto unlock_and_exit;
 139         }
 140
 141         /* Check for an existing internal object, might not exist */
 142
 143         obj_desc = acpi_ns_get_attached_object(node);
 144         if (!obj_desc) {
 145
 146                 /* Create a new object */
 147
 148                 obj_desc = acpi_ut_create_internal_object(node->type);
 149                 if (!obj_desc) {
 150                         status = AE_NO_MEMORY;
 151                         goto unlock_and_exit;
 152                 }
 153
 154                 /* Attach new object to the Node, remove local reference */
 155
 156                 status = acpi_ns_attach_object(device, obj_desc, node->type);
 157                 acpi_ut_remove_reference(obj_desc);
 158                 if (ACPI_FAILURE(status)) {
 159                         goto unlock_and_exit;
 160                 }
 161         }
 162
 163         /* Ensure that the handler is not already installed in the lists */
 164
 165         for (i = 0; i < ACPI_NUM_NOTIFY_TYPES; i++) {
 166                 if (handler_type & (i + 1)) {
 167                         handler_obj = obj_desc->common_notify.notify_list[i];
 168                         while (handler_obj) {
 169                                 if (handler_obj->notify.handler == handler) {
 170                                         status = AE_ALREADY_EXISTS;
 171                                         goto unlock_and_exit;
 172                                 }
 173
 174                                 handler_obj = handler_obj->notify.next[i];
 175                         }
 176                 }
 177         }
 178
 179         /* Create and populate a new notify handler object */
 180
 181         handler_obj = acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_NOTIFY);
 182         if (!handler_obj) {
 183                 status = AE_NO_MEMORY;
 184                 goto unlock_and_exit;
 185         }
 186
 187         handler_obj->notify.node = node;
 188         handler_obj->notify.handler_type = handler_type;
 189         handler_obj->notify.handler = handler;
 190         handler_obj->notify.context = context;
 191
 192         /* Install the handler at the list head(s) */
 193
 194         for (i = 0; i < ACPI_NUM_NOTIFY_TYPES; i++) {
 195                 if (handler_type & (i + 1)) {
 196                         handler_obj->notify.next[i] =
 197                             obj_desc->common_notify.notify_list[i];
 198
 199                         obj_desc->common_notify.notify_list[i] = handler_obj;
 200                 }
 201         }
 202
 203         /* Add an extra reference if handler was installed in both lists */
 204
 205         if (handler_type == ACPI_ALL_NOTIFY) {
 206                 acpi_ut_add_reference(handler_obj);
 207         }
 208
 209 unlock_and_exit:
 210         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 211         return_ACPI_STATUS(status);
 212 }
 213
 214 ACPI_EXPORT_SYMBOL(acpi_install_notify_handler)
 215
 216 /*******************************************************************************
 217  *
 218  * FUNCTION:    acpi_remove_notify_handler
 219  *
 220  * PARAMETERS:  device          - The device for which the handler is installed
 221  *              handler_type    - The type of handler:
 222  *                                  ACPI_SYSTEM_NOTIFY: System Handler (00-7F)
 223  *                                  ACPI_DEVICE_NOTIFY: Device Handler (80-FF)
 224  *                                  ACPI_ALL_NOTIFY:    Both System and Device
 225  *              handler         - Address of the handler
 226  *
 227  * RETURN:      Status
 228  *
 229  * DESCRIPTION: Remove a handler for notifies on an ACPI device
 230  *
 231  ******************************************************************************/
 232 acpi_status
 233 acpi_remove_notify_handler(acpi_handle device,
 234                            u32 handler_type, acpi_notify_handler handler)
 235 {
 236         struct acpi_namespace_node *node =
 237             ACPI_CAST_PTR(struct acpi_namespace_node, device);
 238         union acpi_operand_object *obj_desc;
 239         union acpi_operand_object *handler_obj;
 240         union acpi_operand_object *previous_handler_obj;
 241         acpi_status status;
 242         u32 i;
 243
 244         ACPI_FUNCTION_TRACE(acpi_remove_notify_handler);
 245
 246         /* Parameter validation */
 247
 248         if ((!device) || (!handler) || (!handler_type) ||
 249             (handler_type > ACPI_MAX_NOTIFY_HANDLER_TYPE)) {
 250                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 251         }
 252
 253         /* Make sure all deferred notify tasks are completed */
 254
 255         acpi_os_wait_events_complete();
 256
 257         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 258         if (ACPI_FAILURE(status)) {
 259                 return_ACPI_STATUS(status);
 260         }
 261
 262         /* Root Object. Global handlers are removed here */
 263
 264         if (device == ACPI_ROOT_OBJECT) {
 265                 for (i = 0; i < ACPI_NUM_NOTIFY_TYPES; i++) {
 266                         if (handler_type & (i + 1)) {
 267                                 if (!acpi_gbl_global_notify[i].handler ||
 268                                     (acpi_gbl_global_notify[i].handler !=
 269                                      handler)) {
 270                                         status = AE_NOT_EXIST;
 271                                         goto unlock_and_exit;
 272                                 }
 273
 274                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 275                                                   "Removing global notify handler\n"));
 276
 277                                 acpi_gbl_global_notify[i].handler = NULL;
 278                                 acpi_gbl_global_notify[i].context = NULL;
 279                         }
 280                 }
 281
 282                 goto unlock_and_exit;
 283         }
 284
 285         /* All other objects: Are Notifies allowed on this object? */
 286
 287         if (!acpi_ev_is_notify_object(node)) {
 288                 status = AE_TYPE;
 289                 goto unlock_and_exit;
 290         }
 291
 292         /* Must have an existing internal object */
 293
 294         obj_desc = acpi_ns_get_attached_object(node);
 295         if (!obj_desc) {
 296                 status = AE_NOT_EXIST;
 297                 goto unlock_and_exit;
 298         }
 299
 300         /* Internal object exists. Find the handler and remove it */
 301
 302         for (i = 0; i < ACPI_NUM_NOTIFY_TYPES; i++) {
 303                 if (handler_type & (i + 1)) {
 304                         handler_obj = obj_desc->common_notify.notify_list[i];
 305                         previous_handler_obj = NULL;
 306
 307                         /* Attempt to find the handler in the handler list */
 308
 309                         while (handler_obj &&
 310                                (handler_obj->notify.handler != handler)) {
 311                                 previous_handler_obj = handler_obj;
 312                                 handler_obj = handler_obj->notify.next[i];
 313                         }
 314
 315                         if (!handler_obj) {
 316                                 status = AE_NOT_EXIST;
 317                                 goto unlock_and_exit;
 318                         }
 319
 320                         /* Remove the handler object from the list */
 321
 322                         if (previous_handler_obj) {     /* Handler is not at the list head */
 323                                 previous_handler_obj->notify.next[i] =
 324                                     handler_obj->notify.next[i];
 325                         } else {        /* Handler is at the list head */
 326
 327                                 obj_desc->common_notify.notify_list[i] =
 328                                     handler_obj->notify.next[i];
 329                         }
 330
 331                         acpi_ut_remove_reference(handler_obj);
 332                 }
 333         }
 334
 335 unlock_and_exit:
 336         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 337         return_ACPI_STATUS(status);
 338 }
 339
 340 ACPI_EXPORT_SYMBOL(acpi_remove_notify_handler)
 341
 342 /*******************************************************************************
 343  *
 344  * FUNCTION:    acpi_install_exception_handler
 345  *
 346  * PARAMETERS:  handler         - Pointer to the handler function for the
 347  *                                event
 348  *
 349  * RETURN:      Status
 350  *
 351  * DESCRIPTION: Saves the pointer to the handler function
 352  *
 353  ******************************************************************************/
 354 #ifdef ACPI_FUTURE_USAGE
 355 acpi_status acpi_install_exception_handler(acpi_exception_handler handler)
 356 {
 357         acpi_status status;
 358
 359         ACPI_FUNCTION_TRACE(acpi_install_exception_handler);
 360
 361         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 362         if (ACPI_FAILURE(status)) {
 363                 return_ACPI_STATUS(status);
 364         }
 365
 366         /* Don't allow two handlers. */
 367
 368         if (acpi_gbl_exception_handler) {
 369                 status = AE_ALREADY_EXISTS;
 370                 goto cleanup;
 371         }
 372
 373         /* Install the handler */
 374
 375         acpi_gbl_exception_handler = handler;
 376
 377       cleanup:
 378         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 379         return_ACPI_STATUS(status);
 380 }
 381
 382 ACPI_EXPORT_SYMBOL(acpi_install_exception_handler)
 383 #endif                          /*  ACPI_FUTURE_USAGE  */
 384
 385 #if (!ACPI_REDUCED_HARDWARE)
 386 /*******************************************************************************
 387  *
 388  * FUNCTION:    acpi_install_global_event_handler
 389  *
 390  * PARAMETERS:  handler         - Pointer to the global event handler function
 391  *              context         - Value passed to the handler on each event
 392  *
 393  * RETURN:      Status
 394  *
 395  * DESCRIPTION: Saves the pointer to the handler function. The global handler
 396  *              is invoked upon each incoming GPE and Fixed Event. It is
 397  *              invoked at interrupt level at the time of the event dispatch.
 398  *              Can be used to update event counters, etc.
 399  *
 400  ******************************************************************************/
 401 acpi_status
 402 acpi_install_global_event_handler(acpi_gbl_event_handler handler, void *context)
 403 {
 404         acpi_status status;
 405
 406         ACPI_FUNCTION_TRACE(acpi_install_global_event_handler);
 407
 408         /* Parameter validation */
 409
 410         if (!handler) {
 411                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 412         }
 413
 414         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 415         if (ACPI_FAILURE(status)) {
 416                 return_ACPI_STATUS(status);
 417         }
 418
 419         /* Don't allow two handlers. */
 420
 421         if (acpi_gbl_global_event_handler) {
 422                 status = AE_ALREADY_EXISTS;
 423                 goto cleanup;
 424         }
 425
 426         acpi_gbl_global_event_handler = handler;
 427         acpi_gbl_global_event_handler_context = context;
 428
 429       cleanup:
 430         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 431         return_ACPI_STATUS(status);
 432 }
 433
 434 ACPI_EXPORT_SYMBOL(acpi_install_global_event_handler)
 435
 436 /*******************************************************************************
 437  *
 438  * FUNCTION:    acpi_install_fixed_event_handler
 439  *
 440  * PARAMETERS:  event           - Event type to enable.
 441  *              handler         - Pointer to the handler function for the
 442  *                                event
 443  *              context         - Value passed to the handler on each GPE
 444  *
 445  * RETURN:      Status
 446  *
 447  * DESCRIPTION: Saves the pointer to the handler function and then enables the
 448  *              event.
 449  *
 450  ******************************************************************************/
 451 acpi_status
 452 acpi_install_fixed_event_handler(u32 event,
 453                                  acpi_event_handler handler, void *context)
 454 {
 455         acpi_status status;
 456
 457         ACPI_FUNCTION_TRACE(acpi_install_fixed_event_handler);
 458
 459         /* Parameter validation */
 460
 461         if (event > ACPI_EVENT_MAX) {
 462                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 463         }
 464
 465         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 466         if (ACPI_FAILURE(status)) {
 467                 return_ACPI_STATUS(status);
 468         }
 469
 470         /* Do not allow multiple handlers */
 471
 472         if (acpi_gbl_fixed_event_handlers[event].handler) {
 473                 status = AE_ALREADY_EXISTS;
 474                 goto cleanup;
 475         }
 476
 477         /* Install the handler before enabling the event */
 478
 479         acpi_gbl_fixed_event_handlers[event].handler = handler;
 480         acpi_gbl_fixed_event_handlers[event].context = context;
 481
 482         status = acpi_clear_event(event);
 483         if (ACPI_SUCCESS(status))
 484                 status = acpi_enable_event(event, 0);
 485         if (ACPI_FAILURE(status)) {
 486                 ACPI_WARNING((AE_INFO,
 487                               "Could not enable fixed event - %s (%u)",
 488                               acpi_ut_get_event_name(event), event));
 489
 490                 /* Remove the handler */
 491
 492                 acpi_gbl_fixed_event_handlers[event].handler = NULL;
 493                 acpi_gbl_fixed_event_handlers[event].context = NULL;
 494         } else {
 495                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 496                                   "Enabled fixed event %s (%X), Handler=%p\n",
 497                                   acpi_ut_get_event_name(event), event,
 498                                   handler));
 499         }
 500
 501       cleanup:
 502         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 503         return_ACPI_STATUS(status);
 504 }
 505
 506 ACPI_EXPORT_SYMBOL(acpi_install_fixed_event_handler)
 507
 508 /*******************************************************************************
 509  *
 510  * FUNCTION:    acpi_remove_fixed_event_handler
 511  *
 512  * PARAMETERS:  event           - Event type to disable.
 513  *              handler         - Address of the handler
 514  *
 515  * RETURN:      Status
 516  *
 517  * DESCRIPTION: Disables the event and unregisters the event handler.
 518  *
 519  ******************************************************************************/
 520 acpi_status
 521 acpi_remove_fixed_event_handler(u32 event, acpi_event_handler handler)
 522 {
 523         acpi_status status = AE_OK;
 524
 525         ACPI_FUNCTION_TRACE(acpi_remove_fixed_event_handler);
 526
 527         /* Parameter validation */
 528
 529         if (event > ACPI_EVENT_MAX) {
 530                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 531         }
 532
 533         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 534         if (ACPI_FAILURE(status)) {
 535                 return_ACPI_STATUS(status);
 536         }
 537
 538         /* Disable the event before removing the handler */
 539
 540         status = acpi_disable_event(event, 0);
 541
 542         /* Always Remove the handler */
 543
 544         acpi_gbl_fixed_event_handlers[event].handler = NULL;
 545         acpi_gbl_fixed_event_handlers[event].context = NULL;
 546
 547         if (ACPI_FAILURE(status)) {
 548                 ACPI_WARNING((AE_INFO,
 549                               "Could not disable fixed event - %s (%u)",
 550                               acpi_ut_get_event_name(event), event));
 551         } else {
 552                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 553                                   "Disabled fixed event - %s (%X)\n",
 554                                   acpi_ut_get_event_name(event), event));
 555         }
 556
 557         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 558         return_ACPI_STATUS(status);
 559 }
 560
 561 ACPI_EXPORT_SYMBOL(acpi_remove_fixed_event_handler)
 562
 563 /*******************************************************************************
 564  *
 565  * FUNCTION:    acpi_install_gpe_handler
 566  *
 567  * PARAMETERS:  gpe_device      - Namespace node for the GPE (NULL for FADT
 568  *                                defined GPEs)
 569  *              gpe_number      - The GPE number within the GPE block
 570  *              type            - Whether this GPE should be treated as an
 571  *                                edge- or level-triggered interrupt.
 572  *              address         - Address of the handler
 573  *              context         - Value passed to the handler on each GPE
 574  *
 575  * RETURN:      Status
 576  *
 577  * DESCRIPTION: Install a handler for a General Purpose Event.
 578  *
 579  ******************************************************************************/
 580 acpi_status
 581 acpi_install_gpe_handler(acpi_handle gpe_device,
 582                          u32 gpe_number,
 583                          u32 type, acpi_gpe_handler address, void *context)
 584 {
 585         struct acpi_gpe_event_info *gpe_event_info;
 586         struct acpi_gpe_handler_info *handler;
 587         acpi_status status;
 588         acpi_cpu_flags flags;
 589
 590         ACPI_FUNCTION_TRACE(acpi_install_gpe_handler);
 591
 592         /* Parameter validation */
 593
 594         if ((!address) || (type & ~ACPI_GPE_XRUPT_TYPE_MASK)) {
 595                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 596         }
 597
 598         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 599         if (ACPI_FAILURE(status)) {
 600                 return_ACPI_STATUS(status);
 601         }
 602
 603         /* Allocate and init handler object (before lock) */
 604
 605         handler = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_gpe_handler_info));
 606         if (!handler) {
 607                 status = AE_NO_MEMORY;
 608                 goto unlock_and_exit;
 609         }
 610
 611         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 612
 613         /* Ensure that we have a valid GPE number */
 614
 615         gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
 616         if (!gpe_event_info) {
 617                 status = AE_BAD_PARAMETER;
 618                 goto free_and_exit;
 619         }
 620
 621         /* Make sure that there isn't a handler there already */
 622
 623         if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
 624             ACPI_GPE_DISPATCH_HANDLER) {
 625                 status = AE_ALREADY_EXISTS;
 626                 goto free_and_exit;
 627         }
 628
 629         handler->address = address;
 630         handler->context = context;
 631         handler->method_node = gpe_event_info->dispatch.method_node;
 632         handler->original_flags = (u8)(gpe_event_info->flags &
 633                                        (ACPI_GPE_XRUPT_TYPE_MASK |
 634                                         ACPI_GPE_DISPATCH_MASK));
 635
 636         /*
 637          * If the GPE is associated with a method, it may have been enabled
 638          * automatically during initialization, in which case it has to be
 639          * disabled now to avoid spurious execution of the handler.
 640          */
 641
 642         if ((handler->original_flags & ACPI_GPE_DISPATCH_METHOD)
 643             && gpe_event_info->runtime_count) {
 644                 handler->originally_enabled = 1;
 645                 (void)acpi_ev_remove_gpe_reference(gpe_event_info);
 646         }
 647
 648         /* Install the handler */
 649
 650         gpe_event_info->dispatch.handler = handler;
 651
 652         /* Setup up dispatch flags to indicate handler (vs. method/notify) */
 653
 654         gpe_event_info->flags &=
 655             ~(ACPI_GPE_XRUPT_TYPE_MASK | ACPI_GPE_DISPATCH_MASK);
 656         gpe_event_info->flags |= (u8) (type | ACPI_GPE_DISPATCH_HANDLER);
 657
 658         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 659
 660 unlock_and_exit:
 661         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 662         return_ACPI_STATUS(status);
 663
 664 free_and_exit:
 665         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 666         ACPI_FREE(handler);
 667         goto unlock_and_exit;
 668 }
 669
 670 ACPI_EXPORT_SYMBOL(acpi_install_gpe_handler)
 671
 672 /*******************************************************************************
 673  *
 674  * FUNCTION:    acpi_remove_gpe_handler
 675  *
 676  * PARAMETERS:  gpe_device      - Namespace node for the GPE (NULL for FADT
 677  *                                defined GPEs)
 678  *              gpe_number      - The event to remove a handler
 679  *              address         - Address of the handler
 680  *
 681  * RETURN:      Status
 682  *
 683  * DESCRIPTION: Remove a handler for a General Purpose acpi_event.
 684  *
 685  ******************************************************************************/
 686 acpi_status
 687 acpi_remove_gpe_handler(acpi_handle gpe_device,
 688                         u32 gpe_number, acpi_gpe_handler address)
 689 {
 690         struct acpi_gpe_event_info *gpe_event_info;
 691         struct acpi_gpe_handler_info *handler;
 692         acpi_status status;
 693         acpi_cpu_flags flags;
 694
 695         ACPI_FUNCTION_TRACE(acpi_remove_gpe_handler);
 696
 697         /* Parameter validation */
 698
 699         if (!address) {
 700                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 701         }
 702
 703         /* Make sure all deferred GPE tasks are completed */
 704
 705         acpi_os_wait_events_complete();
 706
 707         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 708         if (ACPI_FAILURE(status)) {
 709                 return_ACPI_STATUS(status);
 710         }
 711
 712         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 713
 714         /* Ensure that we have a valid GPE number */
 715
 716         gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
 717         if (!gpe_event_info) {
 718                 status = AE_BAD_PARAMETER;
 719                 goto unlock_and_exit;
 720         }
 721
 722         /* Make sure that a handler is indeed installed */
 723
 724         if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) !=
 725             ACPI_GPE_DISPATCH_HANDLER) {
 726                 status = AE_NOT_EXIST;
 727                 goto unlock_and_exit;
 728         }
 729
 730         /* Make sure that the installed handler is the same */
 731
 732         if (gpe_event_info->dispatch.handler->address != address) {
 733                 status = AE_BAD_PARAMETER;
 734                 goto unlock_and_exit;
 735         }
 736
 737         /* Remove the handler */
 738
 739         handler = gpe_event_info->dispatch.handler;
 740
 741         /* Restore Method node (if any), set dispatch flags */
 742
 743         gpe_event_info->dispatch.method_node = handler->method_node;
 744         gpe_event_info->flags &=
 745                 ~(ACPI_GPE_XRUPT_TYPE_MASK | ACPI_GPE_DISPATCH_MASK);
 746         gpe_event_info->flags |= handler->original_flags;
 747
 748         /*
 749          * If the GPE was previously associated with a method and it was
 750          * enabled, it should be enabled at this point to restore the
 751          * post-initialization configuration.
 752          */
 753         if ((handler->original_flags & ACPI_GPE_DISPATCH_METHOD) &&
 754             handler->originally_enabled) {
 755                 (void)acpi_ev_add_gpe_reference(gpe_event_info);
 756         }
 757
 758         /* Now we can free the handler object */
 759
 760         ACPI_FREE(handler);
 761
 762 unlock_and_exit:
 763         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 764
 765         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 766         return_ACPI_STATUS(status);
 767 }
 768
 769 ACPI_EXPORT_SYMBOL(acpi_remove_gpe_handler)
 770
 771 /*******************************************************************************
 772  *
 773  * FUNCTION:    acpi_acquire_global_lock
 774  *
 775  * PARAMETERS:  timeout         - How long the caller is willing to wait
 776  *              handle          - Where the handle to the lock is returned
 777  *                                (if acquired)
 778  *
 779  * RETURN:      Status
 780  *
 781  * DESCRIPTION: Acquire the ACPI Global Lock
 782  *
 783  * Note: Allows callers with the same thread ID to acquire the global lock
 784  * multiple times. In other words, externally, the behavior of the global lock
 785  * is identical to an AML mutex. On the first acquire, a new handle is
 786  * returned. On any subsequent calls to acquire by the same thread, the same
 787  * handle is returned.
 788  *
 789  ******************************************************************************/
 790 acpi_status acpi_acquire_global_lock(u16 timeout, u32 * handle)
 791 {
 792         acpi_status status;
 793
 794         if (!handle) {
 795                 return (AE_BAD_PARAMETER);
 796         }
 797
 798         /* Must lock interpreter to prevent race conditions */
 799
 800         acpi_ex_enter_interpreter();
 801
 802         status = acpi_ex_acquire_mutex_object(timeout,
 803                                               acpi_gbl_global_lock_mutex,
 804                                               acpi_os_get_thread_id());
 805
 806         if (ACPI_SUCCESS(status)) {
 807
 808                 /* Return the global lock handle (updated in acpi_ev_acquire_global_lock) */
 809
 810                 *handle = acpi_gbl_global_lock_handle;
 811         }
 812
 813         acpi_ex_exit_interpreter();
 814         return (status);
 815 }
 816
 817 ACPI_EXPORT_SYMBOL(acpi_acquire_global_lock)
 818
 819 /*******************************************************************************
 820  *
 821  * FUNCTION:    acpi_release_global_lock
 822  *
 823  * PARAMETERS:  handle      - Returned from acpi_acquire_global_lock
 824  *
 825  * RETURN:      Status
 826  *
 827  * DESCRIPTION: Release the ACPI Global Lock. The handle must be valid.
 828  *
 829  ******************************************************************************/
 830 acpi_status acpi_release_global_lock(u32 handle)
 831 {
 832         acpi_status status;
 833
 834         if (!handle || (handle != acpi_gbl_global_lock_handle)) {
 835                 return (AE_NOT_ACQUIRED);
 836         }
 837
 838         status = acpi_ex_release_mutex_object(acpi_gbl_global_lock_mutex);
 839         return (status);
 840 }
 841
 842 ACPI_EXPORT_SYMBOL(acpi_release_global_lock)
 843 #endif                          /* !ACPI_REDUCED_HARDWARE */