drivers/acpi/acpica/evgpe.c

   1 /******************************************************************************
   2  *
   3  * Module Name: evgpe - General Purpose Event handling and dispatch
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2014, 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 "acevents.h"
  47 #include "acnamesp.h"
  48
  49 #define _COMPONENT          ACPI_EVENTS
  50 ACPI_MODULE_NAME("evgpe")
  51 #if (!ACPI_REDUCED_HARDWARE)    /* Entire module */
  52 /* Local prototypes */
  53 static void ACPI_SYSTEM_XFACE acpi_ev_asynch_execute_gpe_method(void *context);
  54
  55 static void ACPI_SYSTEM_XFACE acpi_ev_asynch_enable_gpe(void *context);
  56
  57 /*******************************************************************************
  58  *
  59  * FUNCTION:    acpi_ev_update_gpe_enable_mask
  60  *
  61  * PARAMETERS:  gpe_event_info          - GPE to update
  62  *
  63  * RETURN:      Status
  64  *
  65  * DESCRIPTION: Updates GPE register enable mask based upon whether there are
  66  *              runtime references to this GPE
  67  *
  68  ******************************************************************************/
  69
  70 acpi_status
  71 acpi_ev_update_gpe_enable_mask(struct acpi_gpe_event_info *gpe_event_info)
  72 {
  73         struct acpi_gpe_register_info *gpe_register_info;
  74         u32 register_bit;
  75
  76         ACPI_FUNCTION_TRACE(ev_update_gpe_enable_mask);
  77
  78         gpe_register_info = gpe_event_info->register_info;
  79         if (!gpe_register_info) {
  80                 return_ACPI_STATUS(AE_NOT_EXIST);
  81         }
  82
  83         register_bit = acpi_hw_get_gpe_register_bit(gpe_event_info);
  84
  85         /* Clear the run bit up front */
  86
  87         ACPI_CLEAR_BIT(gpe_register_info->enable_for_run, register_bit);
  88
  89         /* Set the mask bit only if there are references to this GPE */
  90
  91         if (gpe_event_info->runtime_count) {
  92                 ACPI_SET_BIT(gpe_register_info->enable_for_run,
  93                              (u8)register_bit);
  94         }
  95
  96         return_ACPI_STATUS(AE_OK);
  97 }
  98
  99 /*******************************************************************************
 100  *
 101  * FUNCTION:    acpi_ev_enable_gpe
 102  *
 103  * PARAMETERS:  gpe_event_info          - GPE to enable
 104  *
 105  * RETURN:      Status
 106  *
 107  * DESCRIPTION: Clear a GPE of stale events and enable it.
 108  *
 109  ******************************************************************************/
 110
 111 acpi_status acpi_ev_enable_gpe(struct acpi_gpe_event_info *gpe_event_info)
 112 {
 113         acpi_status status;
 114
 115         ACPI_FUNCTION_TRACE(ev_enable_gpe);
 116
 117         /* Clear the GPE (of stale events) */
 118
 119         status = acpi_hw_clear_gpe(gpe_event_info);
 120         if (ACPI_FAILURE(status)) {
 121                 return_ACPI_STATUS(status);
 122         }
 123
 124         /* Enable the requested GPE */
 125
 126         status = acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_ENABLE_SAVE);
 127         return_ACPI_STATUS(status);
 128 }
 129
 130 /*******************************************************************************
 131  *
 132  * FUNCTION:    acpi_ev_add_gpe_reference
 133  *
 134  * PARAMETERS:  gpe_event_info          - Add a reference to this GPE
 135  *
 136  * RETURN:      Status
 137  *
 138  * DESCRIPTION: Add a reference to a GPE. On the first reference, the GPE is
 139  *              hardware-enabled.
 140  *
 141  ******************************************************************************/
 142
 143 acpi_status
 144 acpi_ev_add_gpe_reference(struct acpi_gpe_event_info *gpe_event_info)
 145 {
 146         acpi_status status = AE_OK;
 147
 148         ACPI_FUNCTION_TRACE(ev_add_gpe_reference);
 149
 150         if (gpe_event_info->runtime_count == ACPI_UINT8_MAX) {
 151                 return_ACPI_STATUS(AE_LIMIT);
 152         }
 153
 154         gpe_event_info->runtime_count++;
 155         if (gpe_event_info->runtime_count == 1) {
 156
 157                 /* Enable on first reference */
 158
 159                 status = acpi_ev_update_gpe_enable_mask(gpe_event_info);
 160                 if (ACPI_SUCCESS(status)) {
 161                         status = acpi_ev_enable_gpe(gpe_event_info);
 162                 }
 163
 164                 if (ACPI_FAILURE(status)) {
 165                         gpe_event_info->runtime_count--;
 166                 }
 167         }
 168
 169         return_ACPI_STATUS(status);
 170 }
 171
 172 /*******************************************************************************
 173  *
 174  * FUNCTION:    acpi_ev_remove_gpe_reference
 175  *
 176  * PARAMETERS:  gpe_event_info          - Remove a reference to this GPE
 177  *
 178  * RETURN:      Status
 179  *
 180  * DESCRIPTION: Remove a reference to a GPE. When the last reference is
 181  *              removed, the GPE is hardware-disabled.
 182  *
 183  ******************************************************************************/
 184
 185 acpi_status
 186 acpi_ev_remove_gpe_reference(struct acpi_gpe_event_info *gpe_event_info)
 187 {
 188         acpi_status status = AE_OK;
 189
 190         ACPI_FUNCTION_TRACE(ev_remove_gpe_reference);
 191
 192         if (!gpe_event_info->runtime_count) {
 193                 return_ACPI_STATUS(AE_LIMIT);
 194         }
 195
 196         gpe_event_info->runtime_count--;
 197         if (!gpe_event_info->runtime_count) {
 198
 199                 /* Disable on last reference */
 200
 201                 status = acpi_ev_update_gpe_enable_mask(gpe_event_info);
 202                 if (ACPI_SUCCESS(status)) {
 203                         status =
 204                             acpi_hw_low_set_gpe(gpe_event_info,
 205                                                 ACPI_GPE_DISABLE_SAVE);
 206                 }
 207
 208                 if (ACPI_FAILURE(status)) {
 209                         gpe_event_info->runtime_count++;
 210                 }
 211         }
 212
 213         return_ACPI_STATUS(status);
 214 }
 215
 216 /*******************************************************************************
 217  *
 218  * FUNCTION:    acpi_ev_low_get_gpe_info
 219  *
 220  * PARAMETERS:  gpe_number          - Raw GPE number
 221  *              gpe_block           - A GPE info block
 222  *
 223  * RETURN:      A GPE event_info struct. NULL if not a valid GPE (The gpe_number
 224  *              is not within the specified GPE block)
 225  *
 226  * DESCRIPTION: Returns the event_info struct associated with this GPE. This is
 227  *              the low-level implementation of ev_get_gpe_event_info.
 228  *
 229  ******************************************************************************/
 230
 231 struct acpi_gpe_event_info *acpi_ev_low_get_gpe_info(u32 gpe_number,
 232                                                      struct acpi_gpe_block_info
 233                                                      *gpe_block)
 234 {
 235         u32 gpe_index;
 236
 237         /*
 238          * Validate that the gpe_number is within the specified gpe_block.
 239          * (Two steps)
 240          */
 241         if (!gpe_block || (gpe_number < gpe_block->block_base_number)) {
 242                 return (NULL);
 243         }
 244
 245         gpe_index = gpe_number - gpe_block->block_base_number;
 246         if (gpe_index >= gpe_block->gpe_count) {
 247                 return (NULL);
 248         }
 249
 250         return (&gpe_block->event_info[gpe_index]);
 251 }
 252
 253
 254 /*******************************************************************************
 255  *
 256  * FUNCTION:    acpi_ev_get_gpe_event_info
 257  *
 258  * PARAMETERS:  gpe_device          - Device node. NULL for GPE0/GPE1
 259  *              gpe_number          - Raw GPE number
 260  *
 261  * RETURN:      A GPE event_info struct. NULL if not a valid GPE
 262  *
 263  * DESCRIPTION: Returns the event_info struct associated with this GPE.
 264  *              Validates the gpe_block and the gpe_number
 265  *
 266  *              Should be called only when the GPE lists are semaphore locked
 267  *              and not subject to change.
 268  *
 269  ******************************************************************************/
 270
 271 struct acpi_gpe_event_info *acpi_ev_get_gpe_event_info(acpi_handle gpe_device,
 272                                                        u32 gpe_number)
 273 {
 274         union acpi_operand_object *obj_desc;
 275         struct acpi_gpe_event_info *gpe_info;
 276         u32 i;
 277
 278         ACPI_FUNCTION_ENTRY();
 279
 280         /* A NULL gpe_device means use the FADT-defined GPE block(s) */
 281
 282         if (!gpe_device) {
 283
 284                 /* Examine GPE Block 0 and 1 (These blocks are permanent) */
 285
 286                 for (i = 0; i < ACPI_MAX_GPE_BLOCKS; i++) {
 287                         gpe_info = acpi_ev_low_get_gpe_info(gpe_number,
 288                                                             acpi_gbl_gpe_fadt_blocks
 289                                                             [i]);
 290                         if (gpe_info) {
 291                                 return (gpe_info);
 292                         }
 293                 }
 294
 295                 /* The gpe_number was not in the range of either FADT GPE block */
 296
 297                 return (NULL);
 298         }
 299
 300         /* A Non-NULL gpe_device means this is a GPE Block Device */
 301
 302         obj_desc =
 303             acpi_ns_get_attached_object((struct acpi_namespace_node *)
 304                                                gpe_device);
 305         if (!obj_desc || !obj_desc->device.gpe_block) {
 306                 return (NULL);
 307         }
 308
 309         return (acpi_ev_low_get_gpe_info
 310                 (gpe_number, obj_desc->device.gpe_block));
 311 }
 312
 313 /*******************************************************************************
 314  *
 315  * FUNCTION:    acpi_ev_gpe_detect
 316  *
 317  * PARAMETERS:  gpe_xrupt_list      - Interrupt block for this interrupt.
 318  *                                    Can have multiple GPE blocks attached.
 319  *
 320  * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
 321  *
 322  * DESCRIPTION: Detect if any GP events have occurred. This function is
 323  *              executed at interrupt level.
 324  *
 325  ******************************************************************************/
 326
 327 u32 acpi_ev_gpe_detect(struct acpi_gpe_xrupt_info *gpe_xrupt_list)
 328 {
 329         acpi_status status;
 330         struct acpi_gpe_block_info *gpe_block;
 331         struct acpi_namespace_node *gpe_device;
 332         struct acpi_gpe_register_info *gpe_register_info;
 333         struct acpi_gpe_event_info *gpe_event_info;
 334         u32 gpe_number;
 335         u32 int_status = ACPI_INTERRUPT_NOT_HANDLED;
 336         u8 enabled_status_byte;
 337         u32 status_reg;
 338         u32 enable_reg;
 339         acpi_cpu_flags flags;
 340         u32 i;
 341         u32 j;
 342
 343         ACPI_FUNCTION_NAME(ev_gpe_detect);
 344
 345         /* Check for the case where there are no GPEs */
 346
 347         if (!gpe_xrupt_list) {
 348                 return (int_status);
 349         }
 350
 351         /*
 352          * We need to obtain the GPE lock for both the data structs and registers
 353          * Note: Not necessary to obtain the hardware lock, since the GPE
 354          * registers are owned by the gpe_lock.
 355          */
 356         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 357
 358         /* Examine all GPE blocks attached to this interrupt level */
 359
 360         gpe_block = gpe_xrupt_list->gpe_block_list_head;
 361         while (gpe_block) {
 362                 gpe_device = gpe_block->node;
 363
 364                 /*
 365                  * Read all of the 8-bit GPE status and enable registers in this GPE
 366                  * block, saving all of them. Find all currently active GP events.
 367                  */
 368                 for (i = 0; i < gpe_block->register_count; i++) {
 369
 370                         /* Get the next status/enable pair */
 371
 372                         gpe_register_info = &gpe_block->register_info[i];
 373
 374                         /*
 375                          * Optimization: If there are no GPEs enabled within this
 376                          * register, we can safely ignore the entire register.
 377                          */
 378                         if (!(gpe_register_info->enable_for_run |
 379                               gpe_register_info->enable_for_wake)) {
 380                                 ACPI_DEBUG_PRINT((ACPI_DB_INTERRUPTS,
 381                                                   "Ignore disabled registers for GPE %02X-%02X: "
 382                                                   "RunEnable=%02X, WakeEnable=%02X\n",
 383                                                   gpe_register_info->
 384                                                   base_gpe_number,
 385                                                   gpe_register_info->
 386                                                   base_gpe_number +
 387                                                   (ACPI_GPE_REGISTER_WIDTH - 1),
 388                                                   gpe_register_info->
 389                                                   enable_for_run,
 390                                                   gpe_register_info->
 391                                                   enable_for_wake));
 392                                 continue;
 393                         }
 394
 395                         /* Read the Status Register */
 396
 397                         status =
 398                             acpi_hw_read(&status_reg,
 399                                          &gpe_register_info->status_address);
 400                         if (ACPI_FAILURE(status)) {
 401                                 goto unlock_and_exit;
 402                         }
 403
 404                         /* Read the Enable Register */
 405
 406                         status =
 407                             acpi_hw_read(&enable_reg,
 408                                          &gpe_register_info->enable_address);
 409                         if (ACPI_FAILURE(status)) {
 410                                 goto unlock_and_exit;
 411                         }
 412
 413                         ACPI_DEBUG_PRINT((ACPI_DB_INTERRUPTS,
 414                                           "Read registers for GPE %02X-%02X: Status=%02X, Enable=%02X, "
 415                                           "RunEnable=%02X, WakeEnable=%02X\n",
 416                                           gpe_register_info->base_gpe_number,
 417                                           gpe_register_info->base_gpe_number +
 418                                           (ACPI_GPE_REGISTER_WIDTH - 1),
 419                                           status_reg, enable_reg,
 420                                           gpe_register_info->enable_for_run,
 421                                           gpe_register_info->enable_for_wake));
 422
 423                         /* Check if there is anything active at all in this register */
 424
 425                         enabled_status_byte = (u8)(status_reg & enable_reg);
 426                         if (!enabled_status_byte) {
 427
 428                                 /* No active GPEs in this register, move on */
 429
 430                                 continue;
 431                         }
 432
 433                         /* Now look at the individual GPEs in this byte register */
 434
 435                         for (j = 0; j < ACPI_GPE_REGISTER_WIDTH; j++) {
 436
 437                                 /* Examine one GPE bit */
 438
 439                                 gpe_event_info =
 440                                     &gpe_block->
 441                                     event_info[((acpi_size) i *
 442                                                 ACPI_GPE_REGISTER_WIDTH) + j];
 443                                 gpe_number =
 444                                     j + gpe_register_info->base_gpe_number;
 445
 446                                 if (enabled_status_byte & (1 << j)) {
 447
 448                                         /* Invoke global event handler if present */
 449
 450                                         acpi_gpe_count++;
 451                                         if (acpi_gbl_global_event_handler) {
 452                                                 acpi_gbl_global_event_handler
 453                                                     (ACPI_EVENT_TYPE_GPE,
 454                                                      gpe_device, gpe_number,
 455                                                      acpi_gbl_global_event_handler_context);
 456                                         }
 457
 458                                         /*
 459                                          * Found an active GPE. Dispatch the event to a handler
 460                                          * or method.
 461                                          */
 462                                         int_status |=
 463                                             acpi_ev_gpe_dispatch(gpe_device,
 464                                                                  gpe_event_info,
 465                                                                  gpe_number);
 466                                 }
 467                         }
 468                 }
 469
 470                 gpe_block = gpe_block->next;
 471         }
 472
 473 unlock_and_exit:
 474
 475         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 476         return (int_status);
 477 }
 478
 479 /*******************************************************************************
 480  *
 481  * FUNCTION:    acpi_ev_asynch_execute_gpe_method
 482  *
 483  * PARAMETERS:  Context (gpe_event_info) - Info for this GPE
 484  *
 485  * RETURN:      None
 486  *
 487  * DESCRIPTION: Perform the actual execution of a GPE control method. This
 488  *              function is called from an invocation of acpi_os_execute and
 489  *              therefore does NOT execute at interrupt level - so that
 490  *              the control method itself is not executed in the context of
 491  *              an interrupt handler.
 492  *
 493  ******************************************************************************/
 494
 495 static void ACPI_SYSTEM_XFACE acpi_ev_asynch_execute_gpe_method(void *context)
 496 {
 497         struct acpi_gpe_event_info *gpe_event_info = context;
 498         acpi_status status = AE_OK;
 499         struct acpi_evaluate_info *info;
 500         struct acpi_gpe_notify_info *notify;
 501
 502         ACPI_FUNCTION_TRACE(ev_asynch_execute_gpe_method);
 503
 504         /* Do the correct dispatch - normal method or implicit notify */
 505
 506         switch (ACPI_GPE_DISPATCH_TYPE(gpe_event_info->flags)) {
 507         case ACPI_GPE_DISPATCH_NOTIFY:
 508                 /*
 509                  * Implicit notify.
 510                  * Dispatch a DEVICE_WAKE notify to the appropriate handler.
 511                  * NOTE: the request is queued for execution after this method
 512                  * completes. The notify handlers are NOT invoked synchronously
 513                  * from this thread -- because handlers may in turn run other
 514                  * control methods.
 515                  *
 516                  * June 2012: Expand implicit notify mechanism to support
 517                  * notifies on multiple device objects.
 518                  */
 519                 notify = gpe_event_info->dispatch.notify_list;
 520                 while (ACPI_SUCCESS(status) && notify) {
 521                         status =
 522                             acpi_ev_queue_notify_request(notify->device_node,
 523                                                          ACPI_NOTIFY_DEVICE_WAKE);
 524
 525                         notify = notify->next;
 526                 }
 527
 528                 break;
 529
 530         case ACPI_GPE_DISPATCH_METHOD:
 531
 532                 /* Allocate the evaluation information block */
 533
 534                 info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
 535                 if (!info) {
 536                         status = AE_NO_MEMORY;
 537                 } else {
 538                         /*
 539                          * Invoke the GPE Method (_Lxx, _Exx) i.e., evaluate the
 540                          * _Lxx/_Exx control method that corresponds to this GPE
 541                          */
 542                         info->prefix_node =
 543                             gpe_event_info->dispatch.method_node;
 544                         info->flags = ACPI_IGNORE_RETURN_VALUE;
 545
 546                         status = acpi_ns_evaluate(info);
 547                         ACPI_FREE(info);
 548                 }
 549
 550                 if (ACPI_FAILURE(status)) {
 551                         ACPI_EXCEPTION((AE_INFO, status,
 552                                         "while evaluating GPE method [%4.4s]",
 553                                         acpi_ut_get_node_name(gpe_event_info->
 554                                                               dispatch.
 555                                                               method_node)));
 556                 }
 557                 break;
 558
 559         default:
 560
 561                 goto error_exit;        /* Should never happen */
 562         }
 563
 564         /* Defer enabling of GPE until all notify handlers are done */
 565
 566         status = acpi_os_execute(OSL_NOTIFY_HANDLER,
 567                                  acpi_ev_asynch_enable_gpe, gpe_event_info);
 568         if (ACPI_SUCCESS(status)) {
 569                 return_VOID;
 570         }
 571
 572 error_exit:
 573         acpi_ev_asynch_enable_gpe(gpe_event_info);
 574         return_VOID;
 575 }
 576
 577
 578 /*******************************************************************************
 579  *
 580  * FUNCTION:    acpi_ev_asynch_enable_gpe
 581  *
 582  * PARAMETERS:  Context (gpe_event_info) - Info for this GPE
 583  *              Callback from acpi_os_execute
 584  *
 585  * RETURN:      None
 586  *
 587  * DESCRIPTION: Asynchronous clear/enable for GPE. This allows the GPE to
 588  *              complete (i.e., finish execution of Notify)
 589  *
 590  ******************************************************************************/
 591
 592 static void ACPI_SYSTEM_XFACE acpi_ev_asynch_enable_gpe(void *context)
 593 {
 594         struct acpi_gpe_event_info *gpe_event_info = context;
 595         acpi_cpu_flags flags;
 596
 597         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 598         (void)acpi_ev_finish_gpe(gpe_event_info);
 599         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 600
 601         return;
 602 }
 603
 604
 605 /*******************************************************************************
 606  *
 607  * FUNCTION:    acpi_ev_finish_gpe
 608  *
 609  * PARAMETERS:  gpe_event_info      - Info for this GPE
 610  *
 611  * RETURN:      Status
 612  *
 613  * DESCRIPTION: Clear/Enable a GPE. Common code that is used after execution
 614  *              of a GPE method or a synchronous or asynchronous GPE handler.
 615  *
 616  ******************************************************************************/
 617
 618 acpi_status acpi_ev_finish_gpe(struct acpi_gpe_event_info * gpe_event_info)
 619 {
 620         acpi_status status;
 621
 622         if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
 623             ACPI_GPE_LEVEL_TRIGGERED) {
 624                 /*
 625                  * GPE is level-triggered, we clear the GPE status bit after
 626                  * handling the event.
 627                  */
 628                 status = acpi_hw_clear_gpe(gpe_event_info);
 629                 if (ACPI_FAILURE(status)) {
 630                         return (status);
 631                 }
 632         }
 633
 634         /*
 635          * Enable this GPE, conditionally. This means that the GPE will
 636          * only be physically enabled if the enable_mask bit is set
 637          * in the event_info.
 638          */
 639         (void)acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_CONDITIONAL_ENABLE);
 640         return (AE_OK);
 641 }
 642
 643
 644 /*******************************************************************************
 645  *
 646  * FUNCTION:    acpi_ev_gpe_dispatch
 647  *
 648  * PARAMETERS:  gpe_device          - Device node. NULL for GPE0/GPE1
 649  *              gpe_event_info      - Info for this GPE
 650  *              gpe_number          - Number relative to the parent GPE block
 651  *
 652  * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
 653  *
 654  * DESCRIPTION: Dispatch a General Purpose Event to either a function (e.g. EC)
 655  *              or method (e.g. _Lxx/_Exx) handler.
 656  *
 657  *              This function executes at interrupt level.
 658  *
 659  ******************************************************************************/
 660
 661 u32
 662 acpi_ev_gpe_dispatch(struct acpi_namespace_node *gpe_device,
 663                      struct acpi_gpe_event_info *gpe_event_info, u32 gpe_number)
 664 {
 665         acpi_status status;
 666         u32 return_value;
 667
 668         ACPI_FUNCTION_TRACE(ev_gpe_dispatch);
 669
 670         /*
 671          * Always disable the GPE so that it does not keep firing before
 672          * any asynchronous activity completes (either from the execution
 673          * of a GPE method or an asynchronous GPE handler.)
 674          *
 675          * If there is no handler or method to run, just disable the
 676          * GPE and leave it disabled permanently to prevent further such
 677          * pointless events from firing.
 678          */
 679         status = acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_DISABLE);
 680         if (ACPI_FAILURE(status)) {
 681                 ACPI_EXCEPTION((AE_INFO, status,
 682                                 "Unable to disable GPE %02X", gpe_number));
 683                 return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
 684         }
 685
 686         /*
 687          * If edge-triggered, clear the GPE status bit now. Note that
 688          * level-triggered events are cleared after the GPE is serviced.
 689          */
 690         if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
 691             ACPI_GPE_EDGE_TRIGGERED) {
 692                 status = acpi_hw_clear_gpe(gpe_event_info);
 693                 if (ACPI_FAILURE(status)) {
 694                         ACPI_EXCEPTION((AE_INFO, status,
 695                                         "Unable to clear GPE %02X",
 696                                         gpe_number));
 697                         (void)acpi_hw_low_set_gpe(gpe_event_info,
 698                                                   ACPI_GPE_CONDITIONAL_ENABLE);
 699                         return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
 700                 }
 701         }
 702
 703         /*
 704          * Dispatch the GPE to either an installed handler or the control
 705          * method associated with this GPE (_Lxx or _Exx). If a handler
 706          * exists, we invoke it and do not attempt to run the method.
 707          * If there is neither a handler nor a method, leave the GPE
 708          * disabled.
 709          */
 710         switch (ACPI_GPE_DISPATCH_TYPE(gpe_event_info->flags)) {
 711         case ACPI_GPE_DISPATCH_HANDLER:
 712
 713                 /* Invoke the installed handler (at interrupt level) */
 714
 715                 return_value =
 716                     gpe_event_info->dispatch.handler->address(gpe_device,
 717                                                               gpe_number,
 718                                                               gpe_event_info->
 719                                                               dispatch.handler->
 720                                                               context);
 721
 722                 /* If requested, clear (if level-triggered) and reenable the GPE */
 723
 724                 if (return_value & ACPI_REENABLE_GPE) {
 725                         (void)acpi_ev_finish_gpe(gpe_event_info);
 726                 }
 727                 break;
 728
 729         case ACPI_GPE_DISPATCH_METHOD:
 730         case ACPI_GPE_DISPATCH_NOTIFY:
 731                 /*
 732                  * Execute the method associated with the GPE
 733                  * NOTE: Level-triggered GPEs are cleared after the method completes.
 734                  */
 735                 status = acpi_os_execute(OSL_GPE_HANDLER,
 736                                          acpi_ev_asynch_execute_gpe_method,
 737                                          gpe_event_info);
 738                 if (ACPI_FAILURE(status)) {
 739                         ACPI_EXCEPTION((AE_INFO, status,
 740                                         "Unable to queue handler for GPE %02X - event disabled",
 741                                         gpe_number));
 742                 }
 743                 break;
 744
 745         default:
 746                 /*
 747                  * No handler or method to run!
 748                  * 03/2010: This case should no longer be possible. We will not allow
 749                  * a GPE to be enabled if it has no handler or method.
 750                  */
 751                 ACPI_ERROR((AE_INFO,
 752                             "No handler or method for GPE %02X, disabling event",
 753                             gpe_number));
 754
 755                 break;
 756         }
 757
 758         return_UINT32(ACPI_INTERRUPT_HANDLED);
 759 }
 760
 761 #endif                          /* !ACPI_REDUCED_HARDWARE */