kernel/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 - 2015, 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         gpe_register_info->enable_mask = gpe_register_info->enable_for_run;
  96
  97         return_ACPI_STATUS(AE_OK);
  98 }
  99
 100 /*******************************************************************************
 101  *
 102  * FUNCTION:    acpi_ev_enable_gpe
 103  *
 104  * PARAMETERS:  gpe_event_info          - GPE to enable
 105  *
 106  * RETURN:      Status
 107  *
 108  * DESCRIPTION: Clear a GPE of stale events and enable it.
 109  *
 110  ******************************************************************************/
 111
 112 acpi_status acpi_ev_enable_gpe(struct acpi_gpe_event_info *gpe_event_info)
 113 {
 114         acpi_status status;
 115
 116         ACPI_FUNCTION_TRACE(ev_enable_gpe);
 117
 118         /* Clear the GPE (of stale events) */
 119
 120         status = acpi_hw_clear_gpe(gpe_event_info);
 121         if (ACPI_FAILURE(status)) {
 122                 return_ACPI_STATUS(status);
 123         }
 124
 125         /* Enable the requested GPE */
 126
 127         status = acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_ENABLE);
 128         return_ACPI_STATUS(status);
 129 }
 130
 131 /*******************************************************************************
 132  *
 133  * FUNCTION:    acpi_ev_add_gpe_reference
 134  *
 135  * PARAMETERS:  gpe_event_info          - Add a reference to this GPE
 136  *
 137  * RETURN:      Status
 138  *
 139  * DESCRIPTION: Add a reference to a GPE. On the first reference, the GPE is
 140  *              hardware-enabled.
 141  *
 142  ******************************************************************************/
 143
 144 acpi_status
 145 acpi_ev_add_gpe_reference(struct acpi_gpe_event_info *gpe_event_info)
 146 {
 147         acpi_status status = AE_OK;
 148
 149         ACPI_FUNCTION_TRACE(ev_add_gpe_reference);
 150
 151         if (gpe_event_info->runtime_count == ACPI_UINT8_MAX) {
 152                 return_ACPI_STATUS(AE_LIMIT);
 153         }
 154
 155         gpe_event_info->runtime_count++;
 156         if (gpe_event_info->runtime_count == 1) {
 157
 158                 /* Enable on first reference */
 159
 160                 status = acpi_ev_update_gpe_enable_mask(gpe_event_info);
 161                 if (ACPI_SUCCESS(status)) {
 162                         status = acpi_ev_enable_gpe(gpe_event_info);
 163                 }
 164
 165                 if (ACPI_FAILURE(status)) {
 166                         gpe_event_info->runtime_count--;
 167                 }
 168         }
 169
 170         return_ACPI_STATUS(status);
 171 }
 172
 173 /*******************************************************************************
 174  *
 175  * FUNCTION:    acpi_ev_remove_gpe_reference
 176  *
 177  * PARAMETERS:  gpe_event_info          - Remove a reference to this GPE
 178  *
 179  * RETURN:      Status
 180  *
 181  * DESCRIPTION: Remove a reference to a GPE. When the last reference is
 182  *              removed, the GPE is hardware-disabled.
 183  *
 184  ******************************************************************************/
 185
 186 acpi_status
 187 acpi_ev_remove_gpe_reference(struct acpi_gpe_event_info *gpe_event_info)
 188 {
 189         acpi_status status = AE_OK;
 190
 191         ACPI_FUNCTION_TRACE(ev_remove_gpe_reference);
 192
 193         if (!gpe_event_info->runtime_count) {
 194                 return_ACPI_STATUS(AE_LIMIT);
 195         }
 196
 197         gpe_event_info->runtime_count--;
 198         if (!gpe_event_info->runtime_count) {
 199
 200                 /* Disable on last reference */
 201
 202                 status = acpi_ev_update_gpe_enable_mask(gpe_event_info);
 203                 if (ACPI_SUCCESS(status)) {
 204                         status =
 205                             acpi_hw_low_set_gpe(gpe_event_info,
 206                                                 ACPI_GPE_DISABLE);
 207                 }
 208
 209                 if (ACPI_FAILURE(status)) {
 210                         gpe_event_info->runtime_count++;
 211                 }
 212         }
 213
 214         return_ACPI_STATUS(status);
 215 }
 216
 217 /*******************************************************************************
 218  *
 219  * FUNCTION:    acpi_ev_low_get_gpe_info
 220  *
 221  * PARAMETERS:  gpe_number          - Raw GPE number
 222  *              gpe_block           - A GPE info block
 223  *
 224  * RETURN:      A GPE event_info struct. NULL if not a valid GPE (The gpe_number
 225  *              is not within the specified GPE block)
 226  *
 227  * DESCRIPTION: Returns the event_info struct associated with this GPE. This is
 228  *              the low-level implementation of ev_get_gpe_event_info.
 229  *
 230  ******************************************************************************/
 231
 232 struct acpi_gpe_event_info *acpi_ev_low_get_gpe_info(u32 gpe_number,
 233                                                      struct acpi_gpe_block_info
 234                                                      *gpe_block)
 235 {
 236         u32 gpe_index;
 237
 238         /*
 239          * Validate that the gpe_number is within the specified gpe_block.
 240          * (Two steps)
 241          */
 242         if (!gpe_block || (gpe_number < gpe_block->block_base_number)) {
 243                 return (NULL);
 244         }
 245
 246         gpe_index = gpe_number - gpe_block->block_base_number;
 247         if (gpe_index >= gpe_block->gpe_count) {
 248                 return (NULL);
 249         }
 250
 251         return (&gpe_block->event_info[gpe_index]);
 252 }
 253
 254
 255 /*******************************************************************************
 256  *
 257  * FUNCTION:    acpi_ev_get_gpe_event_info
 258  *
 259  * PARAMETERS:  gpe_device          - Device node. NULL for GPE0/GPE1
 260  *              gpe_number          - Raw GPE number
 261  *
 262  * RETURN:      A GPE event_info struct. NULL if not a valid GPE
 263  *
 264  * DESCRIPTION: Returns the event_info struct associated with this GPE.
 265  *              Validates the gpe_block and the gpe_number
 266  *
 267  *              Should be called only when the GPE lists are semaphore locked
 268  *              and not subject to change.
 269  *
 270  ******************************************************************************/
 271
 272 struct acpi_gpe_event_info *acpi_ev_get_gpe_event_info(acpi_handle gpe_device,
 273                                                        u32 gpe_number)
 274 {
 275         union acpi_operand_object *obj_desc;
 276         struct acpi_gpe_event_info *gpe_info;
 277         u32 i;
 278
 279         ACPI_FUNCTION_ENTRY();
 280
 281         /* A NULL gpe_device means use the FADT-defined GPE block(s) */
 282
 283         if (!gpe_device) {
 284
 285                 /* Examine GPE Block 0 and 1 (These blocks are permanent) */
 286
 287                 for (i = 0; i < ACPI_MAX_GPE_BLOCKS; i++) {
 288                         gpe_info = acpi_ev_low_get_gpe_info(gpe_number,
 289                                                             acpi_gbl_gpe_fadt_blocks
 290                                                             [i]);
 291                         if (gpe_info) {
 292                                 return (gpe_info);
 293                         }
 294                 }
 295
 296                 /* The gpe_number was not in the range of either FADT GPE block */
 297
 298                 return (NULL);
 299         }
 300
 301         /* A Non-NULL gpe_device means this is a GPE Block Device */
 302
 303         obj_desc =
 304             acpi_ns_get_attached_object((struct acpi_namespace_node *)
 305                                                gpe_device);
 306         if (!obj_desc || !obj_desc->device.gpe_block) {
 307                 return (NULL);
 308         }
 309
 310         return (acpi_ev_low_get_gpe_info
 311                 (gpe_number, obj_desc->device.gpe_block));
 312 }
 313
 314 /*******************************************************************************
 315  *
 316  * FUNCTION:    acpi_ev_gpe_detect
 317  *
 318  * PARAMETERS:  gpe_xrupt_list      - Interrupt block for this interrupt.
 319  *                                    Can have multiple GPE blocks attached.
 320  *
 321  * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
 322  *
 323  * DESCRIPTION: Detect if any GP events have occurred. This function is
 324  *              executed at interrupt level.
 325  *
 326  ******************************************************************************/
 327
 328 u32 acpi_ev_gpe_detect(struct acpi_gpe_xrupt_info *gpe_xrupt_list)
 329 {
 330         acpi_status status;
 331         struct acpi_gpe_block_info *gpe_block;
 332         struct acpi_namespace_node *gpe_device;
 333         struct acpi_gpe_register_info *gpe_register_info;
 334         struct acpi_gpe_event_info *gpe_event_info;
 335         u32 gpe_number;
 336         struct acpi_gpe_handler_info *gpe_handler_info;
 337         u32 int_status = ACPI_INTERRUPT_NOT_HANDLED;
 338         u8 enabled_status_byte;
 339         u32 status_reg;
 340         u32 enable_reg;
 341         acpi_cpu_flags flags;
 342         u32 i;
 343         u32 j;
 344
 345         ACPI_FUNCTION_NAME(ev_gpe_detect);
 346
 347         /* Check for the case where there are no GPEs */
 348
 349         if (!gpe_xrupt_list) {
 350                 return (int_status);
 351         }
 352
 353         /*
 354          * We need to obtain the GPE lock for both the data structs and registers
 355          * Note: Not necessary to obtain the hardware lock, since the GPE
 356          * registers are owned by the gpe_lock.
 357          */
 358         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 359
 360         /* Examine all GPE blocks attached to this interrupt level */
 361
 362         gpe_block = gpe_xrupt_list->gpe_block_list_head;
 363         while (gpe_block) {
 364                 gpe_device = gpe_block->node;
 365
 366                 /*
 367                  * Read all of the 8-bit GPE status and enable registers in this GPE
 368                  * block, saving all of them. Find all currently active GP events.
 369                  */
 370                 for (i = 0; i < gpe_block->register_count; i++) {
 371
 372                         /* Get the next status/enable pair */
 373
 374                         gpe_register_info = &gpe_block->register_info[i];
 375
 376                         /*
 377                          * Optimization: If there are no GPEs enabled within this
 378                          * register, we can safely ignore the entire register.
 379                          */
 380                         if (!(gpe_register_info->enable_for_run |
 381                               gpe_register_info->enable_for_wake)) {
 382                                 ACPI_DEBUG_PRINT((ACPI_DB_INTERRUPTS,
 383                                                   "Ignore disabled registers for GPE %02X-%02X: "
 384                                                   "RunEnable=%02X, WakeEnable=%02X\n",
 385                                                   gpe_register_info->
 386                                                   base_gpe_number,
 387                                                   gpe_register_info->
 388                                                   base_gpe_number +
 389                                                   (ACPI_GPE_REGISTER_WIDTH - 1),
 390                                                   gpe_register_info->
 391                                                   enable_for_run,
 392                                                   gpe_register_info->
 393                                                   enable_for_wake));
 394                                 continue;
 395                         }
 396
 397                         /* Read the Status Register */
 398
 399                         status =
 400                             acpi_hw_read(&status_reg,
 401                                          &gpe_register_info->status_address);
 402                         if (ACPI_FAILURE(status)) {
 403                                 goto unlock_and_exit;
 404                         }
 405
 406                         /* Read the Enable Register */
 407
 408                         status =
 409                             acpi_hw_read(&enable_reg,
 410                                          &gpe_register_info->enable_address);
 411                         if (ACPI_FAILURE(status)) {
 412                                 goto unlock_and_exit;
 413                         }
 414
 415                         ACPI_DEBUG_PRINT((ACPI_DB_INTERRUPTS,
 416                                           "Read registers for GPE %02X-%02X: Status=%02X, Enable=%02X, "
 417                                           "RunEnable=%02X, WakeEnable=%02X\n",
 418                                           gpe_register_info->base_gpe_number,
 419                                           gpe_register_info->base_gpe_number +
 420                                           (ACPI_GPE_REGISTER_WIDTH - 1),
 421                                           status_reg, enable_reg,
 422                                           gpe_register_info->enable_for_run,
 423                                           gpe_register_info->enable_for_wake));
 424
 425                         /* Check if there is anything active at all in this register */
 426
 427                         enabled_status_byte = (u8)(status_reg & enable_reg);
 428                         if (!enabled_status_byte) {
 429
 430                                 /* No active GPEs in this register, move on */
 431
 432                                 continue;
 433                         }
 434
 435                         /* Now look at the individual GPEs in this byte register */
 436
 437                         for (j = 0; j < ACPI_GPE_REGISTER_WIDTH; j++) {
 438
 439                                 /* Examine one GPE bit */
 440
 441                                 gpe_event_info =
 442                                     &gpe_block->
 443                                     event_info[((acpi_size) i *
 444                                                 ACPI_GPE_REGISTER_WIDTH) + j];
 445                                 gpe_number =
 446                                     j + gpe_register_info->base_gpe_number;
 447
 448                                 if (enabled_status_byte & (1 << j)) {
 449
 450                                         /* Invoke global event handler if present */
 451
 452                                         acpi_gpe_count++;
 453                                         if (acpi_gbl_global_event_handler) {
 454                                                 acpi_gbl_global_event_handler
 455                                                     (ACPI_EVENT_TYPE_GPE,
 456                                                      gpe_device, gpe_number,
 457                                                      acpi_gbl_global_event_handler_context);
 458                                         }
 459
 460                                         /* Found an active GPE */
 461
 462                                         if (ACPI_GPE_DISPATCH_TYPE
 463                                             (gpe_event_info->flags) ==
 464                                             ACPI_GPE_DISPATCH_RAW_HANDLER) {
 465
 466                                                 /* Dispatch the event to a raw handler */
 467
 468                                                 gpe_handler_info =
 469                                                     gpe_event_info->dispatch.
 470                                                     handler;
 471
 472                                                 /*
 473                                                  * There is no protection around the namespace node
 474                                                  * and the GPE handler to ensure a safe destruction
 475                                                  * because:
 476                                                  * 1. The namespace node is expected to always
 477                                                  *    exist after loading a table.
 478                                                  * 2. The GPE handler is expected to be flushed by
 479                                                  *    acpi_os_wait_events_complete() before the
 480                                                  *    destruction.
 481                                                  */
 482                                                 acpi_os_release_lock
 483                                                     (acpi_gbl_gpe_lock, flags);
 484                                                 int_status |=
 485                                                     gpe_handler_info->
 486                                                     address(gpe_device,
 487                                                             gpe_number,
 488                                                             gpe_handler_info->
 489                                                             context);
 490                                                 flags =
 491                                                     acpi_os_acquire_lock
 492                                                     (acpi_gbl_gpe_lock);
 493                                         } else {
 494                                                 /*
 495                                                  * Dispatch the event to a standard handler or
 496                                                  * method.
 497                                                  */
 498                                                 int_status |=
 499                                                     acpi_ev_gpe_dispatch
 500                                                     (gpe_device, gpe_event_info,
 501                                                      gpe_number);
 502                                         }
 503                                 }
 504                         }
 505                 }
 506
 507                 gpe_block = gpe_block->next;
 508         }
 509
 510 unlock_and_exit:
 511
 512         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 513         return (int_status);
 514 }
 515
 516 /*******************************************************************************
 517  *
 518  * FUNCTION:    acpi_ev_asynch_execute_gpe_method
 519  *
 520  * PARAMETERS:  Context (gpe_event_info) - Info for this GPE
 521  *
 522  * RETURN:      None
 523  *
 524  * DESCRIPTION: Perform the actual execution of a GPE control method. This
 525  *              function is called from an invocation of acpi_os_execute and
 526  *              therefore does NOT execute at interrupt level - so that
 527  *              the control method itself is not executed in the context of
 528  *              an interrupt handler.
 529  *
 530  ******************************************************************************/
 531
 532 static void ACPI_SYSTEM_XFACE acpi_ev_asynch_execute_gpe_method(void *context)
 533 {
 534         struct acpi_gpe_event_info *gpe_event_info = context;
 535         acpi_status status = AE_OK;
 536         struct acpi_evaluate_info *info;
 537         struct acpi_gpe_notify_info *notify;
 538
 539         ACPI_FUNCTION_TRACE(ev_asynch_execute_gpe_method);
 540
 541         /* Do the correct dispatch - normal method or implicit notify */
 542
 543         switch (ACPI_GPE_DISPATCH_TYPE(gpe_event_info->flags)) {
 544         case ACPI_GPE_DISPATCH_NOTIFY:
 545                 /*
 546                  * Implicit notify.
 547                  * Dispatch a DEVICE_WAKE notify to the appropriate handler.
 548                  * NOTE: the request is queued for execution after this method
 549                  * completes. The notify handlers are NOT invoked synchronously
 550                  * from this thread -- because handlers may in turn run other
 551                  * control methods.
 552                  *
 553                  * June 2012: Expand implicit notify mechanism to support
 554                  * notifies on multiple device objects.
 555                  */
 556                 notify = gpe_event_info->dispatch.notify_list;
 557                 while (ACPI_SUCCESS(status) && notify) {
 558                         status =
 559                             acpi_ev_queue_notify_request(notify->device_node,
 560                                                          ACPI_NOTIFY_DEVICE_WAKE);
 561
 562                         notify = notify->next;
 563                 }
 564
 565                 break;
 566
 567         case ACPI_GPE_DISPATCH_METHOD:
 568
 569                 /* Allocate the evaluation information block */
 570
 571                 info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
 572                 if (!info) {
 573                         status = AE_NO_MEMORY;
 574                 } else {
 575                         /*
 576                          * Invoke the GPE Method (_Lxx, _Exx) i.e., evaluate the
 577                          * _Lxx/_Exx control method that corresponds to this GPE
 578                          */
 579                         info->prefix_node =
 580                             gpe_event_info->dispatch.method_node;
 581                         info->flags = ACPI_IGNORE_RETURN_VALUE;
 582
 583                         status = acpi_ns_evaluate(info);
 584                         ACPI_FREE(info);
 585                 }
 586
 587                 if (ACPI_FAILURE(status)) {
 588                         ACPI_EXCEPTION((AE_INFO, status,
 589                                         "while evaluating GPE method [%4.4s]",
 590                                         acpi_ut_get_node_name(gpe_event_info->
 591                                                               dispatch.
 592                                                               method_node)));
 593                 }
 594                 break;
 595
 596         default:
 597
 598                 goto error_exit;        /* Should never happen */
 599         }
 600
 601         /* Defer enabling of GPE until all notify handlers are done */
 602
 603         status = acpi_os_execute(OSL_NOTIFY_HANDLER,
 604                                  acpi_ev_asynch_enable_gpe, gpe_event_info);
 605         if (ACPI_SUCCESS(status)) {
 606                 return_VOID;
 607         }
 608
 609 error_exit:
 610         acpi_ev_asynch_enable_gpe(gpe_event_info);
 611         return_VOID;
 612 }
 613
 614
 615 /*******************************************************************************
 616  *
 617  * FUNCTION:    acpi_ev_asynch_enable_gpe
 618  *
 619  * PARAMETERS:  Context (gpe_event_info) - Info for this GPE
 620  *              Callback from acpi_os_execute
 621  *
 622  * RETURN:      None
 623  *
 624  * DESCRIPTION: Asynchronous clear/enable for GPE. This allows the GPE to
 625  *              complete (i.e., finish execution of Notify)
 626  *
 627  ******************************************************************************/
 628
 629 static void ACPI_SYSTEM_XFACE acpi_ev_asynch_enable_gpe(void *context)
 630 {
 631         struct acpi_gpe_event_info *gpe_event_info = context;
 632         acpi_cpu_flags flags;
 633
 634         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 635         (void)acpi_ev_finish_gpe(gpe_event_info);
 636         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 637
 638         return;
 639 }
 640
 641
 642 /*******************************************************************************
 643  *
 644  * FUNCTION:    acpi_ev_finish_gpe
 645  *
 646  * PARAMETERS:  gpe_event_info      - Info for this GPE
 647  *
 648  * RETURN:      Status
 649  *
 650  * DESCRIPTION: Clear/Enable a GPE. Common code that is used after execution
 651  *              of a GPE method or a synchronous or asynchronous GPE handler.
 652  *
 653  ******************************************************************************/
 654
 655 acpi_status acpi_ev_finish_gpe(struct acpi_gpe_event_info * gpe_event_info)
 656 {
 657         acpi_status status;
 658
 659         if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
 660             ACPI_GPE_LEVEL_TRIGGERED) {
 661                 /*
 662                  * GPE is level-triggered, we clear the GPE status bit after
 663                  * handling the event.
 664                  */
 665                 status = acpi_hw_clear_gpe(gpe_event_info);
 666                 if (ACPI_FAILURE(status)) {
 667                         return (status);
 668                 }
 669         }
 670
 671         /*
 672          * Enable this GPE, conditionally. This means that the GPE will
 673          * only be physically enabled if the enable_mask bit is set
 674          * in the event_info.
 675          */
 676         (void)acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_CONDITIONAL_ENABLE);
 677         return (AE_OK);
 678 }
 679
 680
 681 /*******************************************************************************
 682  *
 683  * FUNCTION:    acpi_ev_gpe_dispatch
 684  *
 685  * PARAMETERS:  gpe_device          - Device node. NULL for GPE0/GPE1
 686  *              gpe_event_info      - Info for this GPE
 687  *              gpe_number          - Number relative to the parent GPE block
 688  *
 689  * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
 690  *
 691  * DESCRIPTION: Dispatch a General Purpose Event to either a function (e.g. EC)
 692  *              or method (e.g. _Lxx/_Exx) handler.
 693  *
 694  *              This function executes at interrupt level.
 695  *
 696  ******************************************************************************/
 697
 698 u32
 699 acpi_ev_gpe_dispatch(struct acpi_namespace_node *gpe_device,
 700                      struct acpi_gpe_event_info *gpe_event_info, u32 gpe_number)
 701 {
 702         acpi_status status;
 703         u32 return_value;
 704
 705         ACPI_FUNCTION_TRACE(ev_gpe_dispatch);
 706
 707         /*
 708          * Always disable the GPE so that it does not keep firing before
 709          * any asynchronous activity completes (either from the execution
 710          * of a GPE method or an asynchronous GPE handler.)
 711          *
 712          * If there is no handler or method to run, just disable the
 713          * GPE and leave it disabled permanently to prevent further such
 714          * pointless events from firing.
 715          */
 716         status = acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_DISABLE);
 717         if (ACPI_FAILURE(status)) {
 718                 ACPI_EXCEPTION((AE_INFO, status,
 719                                 "Unable to disable GPE %02X", gpe_number));
 720                 return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
 721         }
 722
 723         /*
 724          * If edge-triggered, clear the GPE status bit now. Note that
 725          * level-triggered events are cleared after the GPE is serviced.
 726          */
 727         if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
 728             ACPI_GPE_EDGE_TRIGGERED) {
 729                 status = acpi_hw_clear_gpe(gpe_event_info);
 730                 if (ACPI_FAILURE(status)) {
 731                         ACPI_EXCEPTION((AE_INFO, status,
 732                                         "Unable to clear GPE %02X",
 733                                         gpe_number));
 734                         (void)acpi_hw_low_set_gpe(gpe_event_info,
 735                                                   ACPI_GPE_CONDITIONAL_ENABLE);
 736                         return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
 737                 }
 738         }
 739
 740         /*
 741          * Dispatch the GPE to either an installed handler or the control
 742          * method associated with this GPE (_Lxx or _Exx). If a handler
 743          * exists, we invoke it and do not attempt to run the method.
 744          * If there is neither a handler nor a method, leave the GPE
 745          * disabled.
 746          */
 747         switch (ACPI_GPE_DISPATCH_TYPE(gpe_event_info->flags)) {
 748         case ACPI_GPE_DISPATCH_HANDLER:
 749
 750                 /* Invoke the installed handler (at interrupt level) */
 751
 752                 return_value =
 753                     gpe_event_info->dispatch.handler->address(gpe_device,
 754                                                               gpe_number,
 755                                                               gpe_event_info->
 756                                                               dispatch.handler->
 757                                                               context);
 758
 759                 /* If requested, clear (if level-triggered) and reenable the GPE */
 760
 761                 if (return_value & ACPI_REENABLE_GPE) {
 762                         (void)acpi_ev_finish_gpe(gpe_event_info);
 763                 }
 764                 break;
 765
 766         case ACPI_GPE_DISPATCH_METHOD:
 767         case ACPI_GPE_DISPATCH_NOTIFY:
 768                 /*
 769                  * Execute the method associated with the GPE
 770                  * NOTE: Level-triggered GPEs are cleared after the method completes.
 771                  */
 772                 status = acpi_os_execute(OSL_GPE_HANDLER,
 773                                          acpi_ev_asynch_execute_gpe_method,
 774                                          gpe_event_info);
 775                 if (ACPI_FAILURE(status)) {
 776                         ACPI_EXCEPTION((AE_INFO, status,
 777                                         "Unable to queue handler for GPE %02X - event disabled",
 778                                         gpe_number));
 779                 }
 780                 break;
 781
 782         default:
 783                 /*
 784                  * No handler or method to run!
 785                  * 03/2010: This case should no longer be possible. We will not allow
 786                  * a GPE to be enabled if it has no handler or method.
 787                  */
 788                 ACPI_ERROR((AE_INFO,
 789                             "No handler or method for GPE %02X, disabling event",
 790                             gpe_number));
 791
 792                 break;
 793         }
 794
 795         return_UINT32(ACPI_INTERRUPT_HANDLED);
 796 }
 797
 798 #endif                          /* !ACPI_REDUCED_HARDWARE */