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.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 
  52 #if (!ACPI_REDUCED_HARDWARE) /* Entire module */
  53 
  54 /* Local prototypes */
  55 
  56 static void ACPI_SYSTEM_XFACE
  57 AcpiEvAsynchExecuteGpeMethod (
  58     void                    *Context);
  59 
  60 static void ACPI_SYSTEM_XFACE
  61 AcpiEvAsynchEnableGpe (
  62     void                    *Context);
  63 
  64 
  65 /*******************************************************************************
  66  *
  67  * FUNCTION:    AcpiEvUpdateGpeEnableMask
  68  *
  69  * PARAMETERS:  GpeEventInfo            - GPE to update
  70  *
  71  * RETURN:      Status
  72  *
  73  * DESCRIPTION: Updates GPE register enable mask based upon whether there are
  74  *              runtime references to this GPE
  75  *
  76  ******************************************************************************/
  77 
  78 ACPI_STATUS
  79 AcpiEvUpdateGpeEnableMask (
  80     ACPI_GPE_EVENT_INFO     *GpeEventInfo)
  81 {
  82     ACPI_GPE_REGISTER_INFO  *GpeRegisterInfo;
  83     UINT32                  RegisterBit;
  84 
  85 
  86     ACPI_FUNCTION_TRACE (EvUpdateGpeEnableMask);
  87 
  88 
  89     GpeRegisterInfo = GpeEventInfo->RegisterInfo;
  90     if (!GpeRegisterInfo)
  91     {
  92         return_ACPI_STATUS (AE_NOT_EXIST);
  93     }
  94 
  95     RegisterBit = AcpiHwGetGpeRegisterBit (GpeEventInfo);
  96 
  97     /* Clear the run bit up front */
  98 
  99     ACPI_CLEAR_BIT (GpeRegisterInfo->EnableForRun, RegisterBit);
 100 
 101     /* Set the mask bit only if there are references to this GPE */
 102 
 103     if (GpeEventInfo->RuntimeCount)
 104     {
 105         ACPI_SET_BIT (GpeRegisterInfo->EnableForRun, (UINT8) RegisterBit);
 106     }
 107 
 108     return_ACPI_STATUS (AE_OK);
 109 }
 110 
 111 
 112 /*******************************************************************************
 113  *
 114  * FUNCTION:    AcpiEvEnableGpe
 115  *
 116  * PARAMETERS:  GpeEventInfo            - GPE to enable
 117  *
 118  * RETURN:      Status
 119  *
 120  * DESCRIPTION: Clear a GPE of stale events and enable it.
 121  *
 122  ******************************************************************************/
 123 
 124 ACPI_STATUS
 125 AcpiEvEnableGpe (
 126     ACPI_GPE_EVENT_INFO     *GpeEventInfo)
 127 {
 128     ACPI_STATUS             Status;
 129 
 130 
 131     ACPI_FUNCTION_TRACE (EvEnableGpe);
 132 
 133 
 134     /*
 135      * We will only allow a GPE to be enabled if it has either an associated
 136      * method (_Lxx/_Exx) or a handler, or is using the implicit notify
 137      * feature. Otherwise, the GPE will be immediately disabled by
 138      * AcpiEvGpeDispatch the first time it fires.
 139      */
 140     if ((GpeEventInfo->Flags & ACPI_GPE_DISPATCH_MASK) ==
 141         ACPI_GPE_DISPATCH_NONE)
 142     {
 143         return_ACPI_STATUS (AE_NO_HANDLER);
 144     }
 145 
 146     /* Clear the GPE (of stale events) */
 147 
 148     Status = AcpiHwClearGpe (GpeEventInfo);
 149     if (ACPI_FAILURE (Status))
 150     {
 151         return_ACPI_STATUS (Status);
 152     }
 153 
 154     /* Enable the requested GPE */
 155 
 156     Status = AcpiHwLowSetGpe (GpeEventInfo, ACPI_GPE_ENABLE);
 157     return_ACPI_STATUS (Status);
 158 }
 159 
 160 
 161 /*******************************************************************************
 162  *
 163  * FUNCTION:    AcpiEvAddGpeReference
 164  *
 165  * PARAMETERS:  GpeEventInfo            - Add a reference to this GPE
 166  *
 167  * RETURN:      Status
 168  *
 169  * DESCRIPTION: Add a reference to a GPE. On the first reference, the GPE is
 170  *              hardware-enabled.
 171  *
 172  ******************************************************************************/
 173 
 174 ACPI_STATUS
 175 AcpiEvAddGpeReference (
 176     ACPI_GPE_EVENT_INFO     *GpeEventInfo)
 177 {
 178     ACPI_STATUS             Status = AE_OK;
 179 
 180 
 181     ACPI_FUNCTION_TRACE (EvAddGpeReference);
 182 
 183 
 184     if (GpeEventInfo->RuntimeCount == ACPI_UINT8_MAX)
 185     {
 186         return_ACPI_STATUS (AE_LIMIT);
 187     }
 188 
 189     GpeEventInfo->RuntimeCount++;
 190     if (GpeEventInfo->RuntimeCount == 1)
 191     {
 192         /* Enable on first reference */
 193 
 194         Status = AcpiEvUpdateGpeEnableMask (GpeEventInfo);
 195         if (ACPI_SUCCESS (Status))
 196         {
 197             Status = AcpiEvEnableGpe (GpeEventInfo);
 198         }
 199 
 200         if (ACPI_FAILURE (Status))
 201         {
 202             GpeEventInfo->RuntimeCount--;
 203         }
 204     }
 205 
 206     return_ACPI_STATUS (Status);
 207 }
 208 
 209 
 210 /*******************************************************************************
 211  *
 212  * FUNCTION:    AcpiEvRemoveGpeReference
 213  *
 214  * PARAMETERS:  GpeEventInfo            - Remove a reference to this GPE
 215  *
 216  * RETURN:      Status
 217  *
 218  * DESCRIPTION: Remove a reference to a GPE. When the last reference is
 219  *              removed, the GPE is hardware-disabled.
 220  *
 221  ******************************************************************************/
 222 
 223 ACPI_STATUS
 224 AcpiEvRemoveGpeReference (
 225     ACPI_GPE_EVENT_INFO     *GpeEventInfo)
 226 {
 227     ACPI_STATUS             Status = AE_OK;
 228 
 229 
 230     ACPI_FUNCTION_TRACE (EvRemoveGpeReference);
 231 
 232 
 233     if (!GpeEventInfo->RuntimeCount)
 234     {
 235         return_ACPI_STATUS (AE_LIMIT);
 236     }
 237 
 238     GpeEventInfo->RuntimeCount--;
 239     if (!GpeEventInfo->RuntimeCount)
 240     {
 241         /* Disable on last reference */
 242 
 243         Status = AcpiEvUpdateGpeEnableMask (GpeEventInfo);
 244         if (ACPI_SUCCESS (Status))
 245         {
 246             Status = AcpiHwLowSetGpe (GpeEventInfo, ACPI_GPE_DISABLE);
 247         }
 248 
 249         if (ACPI_FAILURE (Status))
 250         {
 251             GpeEventInfo->RuntimeCount++;
 252         }
 253     }
 254 
 255     return_ACPI_STATUS (Status);
 256 }
 257 
 258 
 259 /*******************************************************************************
 260  *
 261  * FUNCTION:    AcpiEvLowGetGpeInfo
 262  *
 263  * PARAMETERS:  GpeNumber           - Raw GPE number
 264  *              GpeBlock            - A GPE info block
 265  *
 266  * RETURN:      A GPE EventInfo struct. NULL if not a valid GPE (The GpeNumber
 267  *              is not within the specified GPE block)
 268  *
 269  * DESCRIPTION: Returns the EventInfo struct associated with this GPE. This is
 270  *              the low-level implementation of EvGetGpeEventInfo.
 271  *
 272  ******************************************************************************/
 273 
 274 ACPI_GPE_EVENT_INFO *
 275 AcpiEvLowGetGpeInfo (
 276     UINT32                  GpeNumber,
 277     ACPI_GPE_BLOCK_INFO     *GpeBlock)
 278 {
 279     UINT32                  GpeIndex;
 280 
 281 
 282     /*
 283      * Validate that the GpeNumber is within the specified GpeBlock.
 284      * (Two steps)
 285      */
 286     if (!GpeBlock ||
 287         (GpeNumber < GpeBlock->BlockBaseNumber))
 288     {
 289         return (NULL);
 290     }
 291 
 292     GpeIndex = GpeNumber - GpeBlock->BlockBaseNumber;
 293     if (GpeIndex >= GpeBlock->GpeCount)
 294     {
 295         return (NULL);
 296     }
 297 
 298     return (&GpeBlock->EventInfo[GpeIndex]);
 299 }
 300 
 301 
 302 /*******************************************************************************
 303  *
 304  * FUNCTION:    AcpiEvGetGpeEventInfo
 305  *
 306  * PARAMETERS:  GpeDevice           - Device node. NULL for GPE0/GPE1
 307  *              GpeNumber           - Raw GPE number
 308  *
 309  * RETURN:      A GPE EventInfo struct. NULL if not a valid GPE
 310  *
 311  * DESCRIPTION: Returns the EventInfo struct associated with this GPE.
 312  *              Validates the GpeBlock and the GpeNumber
 313  *
 314  *              Should be called only when the GPE lists are semaphore locked
 315  *              and not subject to change.
 316  *
 317  ******************************************************************************/
 318 
 319 ACPI_GPE_EVENT_INFO *
 320 AcpiEvGetGpeEventInfo (
 321     ACPI_HANDLE             GpeDevice,
 322     UINT32                  GpeNumber)
 323 {
 324     ACPI_OPERAND_OBJECT     *ObjDesc;
 325     ACPI_GPE_EVENT_INFO     *GpeInfo;
 326     UINT32                  i;
 327 
 328 
 329     ACPI_FUNCTION_ENTRY ();
 330 
 331 
 332     /* A NULL GpeDevice means use the FADT-defined GPE block(s) */
 333 
 334     if (!GpeDevice)
 335     {
 336         /* Examine GPE Block 0 and 1 (These blocks are permanent) */
 337 
 338         for (i = 0; i < ACPI_MAX_GPE_BLOCKS; i++)
 339         {
 340             GpeInfo = AcpiEvLowGetGpeInfo (GpeNumber,
 341                         AcpiGbl_GpeFadtBlocks[i]);
 342             if (GpeInfo)
 343             {
 344                 return (GpeInfo);
 345             }
 346         }
 347 
 348         /* The GpeNumber was not in the range of either FADT GPE block */
 349 
 350         return (NULL);
 351     }
 352 
 353     /* A Non-NULL GpeDevice means this is a GPE Block Device */
 354 
 355     ObjDesc = AcpiNsGetAttachedObject ((ACPI_NAMESPACE_NODE *) GpeDevice);
 356     if (!ObjDesc ||
 357         !ObjDesc->Device.GpeBlock)
 358     {
 359         return (NULL);
 360     }
 361 
 362     return (AcpiEvLowGetGpeInfo (GpeNumber, ObjDesc->Device.GpeBlock));
 363 }
 364 
 365 
 366 /*******************************************************************************
 367  *
 368  * FUNCTION:    AcpiEvGpeDetect
 369  *
 370  * PARAMETERS:  GpeXruptList        - Interrupt block for this interrupt.
 371  *                                    Can have multiple GPE blocks attached.
 372  *
 373  * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
 374  *
 375  * DESCRIPTION: Detect if any GP events have occurred. This function is
 376  *              executed at interrupt level.
 377  *
 378  ******************************************************************************/
 379 
 380 UINT32
 381 AcpiEvGpeDetect (
 382     ACPI_GPE_XRUPT_INFO     *GpeXruptList)
 383 {
 384     ACPI_STATUS             Status;
 385     ACPI_GPE_BLOCK_INFO     *GpeBlock;
 386     ACPI_GPE_REGISTER_INFO  *GpeRegisterInfo;
 387     UINT32                  IntStatus = ACPI_INTERRUPT_NOT_HANDLED;
 388     UINT8                   EnabledStatusByte;
 389     UINT32                  StatusReg;
 390     UINT32                  EnableReg;
 391     ACPI_CPU_FLAGS          Flags;
 392     UINT32                  i;
 393     UINT32                  j;
 394 
 395 
 396     ACPI_FUNCTION_NAME (EvGpeDetect);
 397 
 398     /* Check for the case where there are no GPEs */
 399 
 400     if (!GpeXruptList)
 401     {
 402         return (IntStatus);
 403     }
 404 
 405     /*
 406      * We need to obtain the GPE lock for both the data structs and registers
 407      * Note: Not necessary to obtain the hardware lock, since the GPE
 408      * registers are owned by the GpeLock.
 409      */
 410     Flags = AcpiOsAcquireLock (AcpiGbl_GpeLock);
 411 
 412     /* Examine all GPE blocks attached to this interrupt level */
 413 
 414     GpeBlock = GpeXruptList->GpeBlockListHead;
 415     while (GpeBlock)
 416     {
 417         /*
 418          * Read all of the 8-bit GPE status and enable registers in this GPE
 419          * block, saving all of them. Find all currently active GP events.
 420          */
 421         for (i = 0; i < GpeBlock->RegisterCount; i++)
 422         {
 423             /* Get the next status/enable pair */
 424 
 425             GpeRegisterInfo = &GpeBlock->RegisterInfo[i];
 426 
 427             /*
 428              * Optimization: If there are no GPEs enabled within this
 429              * register, we can safely ignore the entire register.
 430              */
 431             if (!(GpeRegisterInfo->EnableForRun |
 432                   GpeRegisterInfo->EnableForWake))
 433             {
 434                 ACPI_DEBUG_PRINT ((ACPI_DB_INTERRUPTS,
 435                     "Ignore disabled registers for GPE%02X-GPE%02X: "
 436                     "RunEnable=%02X, WakeEnable=%02X\n",
 437                     GpeRegisterInfo->BaseGpeNumber,
 438                     GpeRegisterInfo->BaseGpeNumber + (ACPI_GPE_REGISTER_WIDTH - 1),
 439                     GpeRegisterInfo->EnableForRun,
 440                     GpeRegisterInfo->EnableForWake));
 441                 continue;
 442             }
 443 
 444             /* Read the Status Register */
 445 
 446             Status = AcpiHwRead (&StatusReg, &GpeRegisterInfo->StatusAddress);
 447             if (ACPI_FAILURE (Status))
 448             {
 449                 goto UnlockAndExit;
 450             }
 451 
 452             /* Read the Enable Register */
 453 
 454             Status = AcpiHwRead (&EnableReg, &GpeRegisterInfo->EnableAddress);
 455             if (ACPI_FAILURE (Status))
 456             {
 457                 goto UnlockAndExit;
 458             }
 459 
 460             ACPI_DEBUG_PRINT ((ACPI_DB_INTERRUPTS,
 461                 "Read registers for GPE%02X-GPE%02X: Status=%02X, Enable=%02X, "
 462                 "RunEnable=%02X, WakeEnable=%02X\n",
 463                 GpeRegisterInfo->BaseGpeNumber,
 464                 GpeRegisterInfo->BaseGpeNumber + (ACPI_GPE_REGISTER_WIDTH - 1),
 465                 StatusReg, EnableReg,
 466                 GpeRegisterInfo->EnableForRun,
 467                 GpeRegisterInfo->EnableForWake));
 468 
 469             /* Check if there is anything active at all in this register */
 470 
 471             EnabledStatusByte = (UINT8) (StatusReg & EnableReg);
 472             if (!EnabledStatusByte)
 473             {
 474                 /* No active GPEs in this register, move on */
 475 
 476                 continue;
 477             }
 478 
 479             /* Now look at the individual GPEs in this byte register */
 480 
 481             for (j = 0; j < ACPI_GPE_REGISTER_WIDTH; j++)
 482             {
 483                 /* Examine one GPE bit */
 484 
 485                 if (EnabledStatusByte & (1 << j))
 486                 {
 487                     /*
 488                      * Found an active GPE. Dispatch the event to a handler
 489                      * or method.
 490                      */
 491                     IntStatus |= AcpiEvGpeDispatch (GpeBlock->Node,
 492                         &GpeBlock->EventInfo[((ACPI_SIZE) i *
 493                             ACPI_GPE_REGISTER_WIDTH) + j],
 494                         j + GpeRegisterInfo->BaseGpeNumber);
 495                 }
 496             }
 497         }
 498 
 499         GpeBlock = GpeBlock->Next;
 500     }
 501 
 502 UnlockAndExit:
 503 
 504     AcpiOsReleaseLock (AcpiGbl_GpeLock, Flags);
 505     return (IntStatus);
 506 }
 507 
 508 
 509 /*******************************************************************************
 510  *
 511  * FUNCTION:    AcpiEvAsynchExecuteGpeMethod
 512  *
 513  * PARAMETERS:  Context (GpeEventInfo) - Info for this GPE
 514  *
 515  * RETURN:      None
 516  *
 517  * DESCRIPTION: Perform the actual execution of a GPE control method. This
 518  *              function is called from an invocation of AcpiOsExecute and
 519  *              therefore does NOT execute at interrupt level - so that
 520  *              the control method itself is not executed in the context of
 521  *              an interrupt handler.
 522  *
 523  ******************************************************************************/
 524 
 525 static void ACPI_SYSTEM_XFACE
 526 AcpiEvAsynchExecuteGpeMethod (
 527     void                    *Context)
 528 {
 529     ACPI_GPE_EVENT_INFO     *GpeEventInfo = Context;
 530     ACPI_STATUS             Status;
 531     ACPI_GPE_EVENT_INFO     *LocalGpeEventInfo;
 532     ACPI_EVALUATE_INFO      *Info;
 533     ACPI_GPE_NOTIFY_INFO    *Notify;
 534 
 535 
 536     ACPI_FUNCTION_TRACE (EvAsynchExecuteGpeMethod);
 537 
 538 
 539     /* Allocate a local GPE block */
 540 
 541     LocalGpeEventInfo = ACPI_ALLOCATE_ZEROED (sizeof (ACPI_GPE_EVENT_INFO));
 542     if (!LocalGpeEventInfo)
 543     {
 544         ACPI_EXCEPTION ((AE_INFO, AE_NO_MEMORY,
 545             "while handling a GPE"));
 546         return_VOID;
 547     }
 548 
 549     Status = AcpiUtAcquireMutex (ACPI_MTX_EVENTS);
 550     if (ACPI_FAILURE (Status))
 551     {
 552         ACPI_FREE (LocalGpeEventInfo);
 553         return_VOID;
 554     }
 555 
 556     /* Must revalidate the GpeNumber/GpeBlock */
 557 
 558     if (!AcpiEvValidGpeEvent (GpeEventInfo))
 559     {
 560         Status = AcpiUtReleaseMutex (ACPI_MTX_EVENTS);
 561         ACPI_FREE (LocalGpeEventInfo);
 562         return_VOID;
 563     }
 564 
 565     /*
 566      * Take a snapshot of the GPE info for this level - we copy the info to
 567      * prevent a race condition with RemoveHandler/RemoveBlock.
 568      */
 569     ACPI_MEMCPY (LocalGpeEventInfo, GpeEventInfo,
 570         sizeof (ACPI_GPE_EVENT_INFO));
 571 
 572     Status = AcpiUtReleaseMutex (ACPI_MTX_EVENTS);
 573     if (ACPI_FAILURE (Status))
 574     {
 575         ACPI_FREE (LocalGpeEventInfo);
 576         return_VOID;
 577     }
 578 
 579     /* Do the correct dispatch - normal method or implicit notify */
 580 
 581     switch (LocalGpeEventInfo->Flags & ACPI_GPE_DISPATCH_MASK)
 582     {
 583     case ACPI_GPE_DISPATCH_NOTIFY:
 584         /*
 585          * Implicit notify.
 586          * Dispatch a DEVICE_WAKE notify to the appropriate handler.
 587          * NOTE: the request is queued for execution after this method
 588          * completes. The notify handlers are NOT invoked synchronously
 589          * from this thread -- because handlers may in turn run other
 590          * control methods.
 591          *
 592          * June 2012: Expand implicit notify mechanism to support
 593          * notifies on multiple device objects.
 594          */
 595         Notify = LocalGpeEventInfo->Dispatch.NotifyList;
 596         while (ACPI_SUCCESS (Status) && Notify)
 597         {
 598             Status = AcpiEvQueueNotifyRequest (Notify->DeviceNode,
 599                         ACPI_NOTIFY_DEVICE_WAKE);
 600 
 601             Notify = Notify->Next;
 602         }
 603         break;
 604 
 605     case ACPI_GPE_DISPATCH_METHOD:
 606 
 607         /* Allocate the evaluation information block */
 608 
 609         Info = ACPI_ALLOCATE_ZEROED (sizeof (ACPI_EVALUATE_INFO));
 610         if (!Info)
 611         {
 612             Status = AE_NO_MEMORY;
 613         }
 614         else
 615         {
 616             /*
 617              * Invoke the GPE Method (_Lxx, _Exx) i.e., evaluate the
 618              * _Lxx/_Exx control method that corresponds to this GPE
 619              */
 620             Info->PrefixNode = LocalGpeEventInfo->Dispatch.MethodNode;
 621             Info->Flags = ACPI_IGNORE_RETURN_VALUE;
 622 
 623             Status = AcpiNsEvaluate (Info);
 624             ACPI_FREE (Info);
 625         }
 626 
 627         if (ACPI_FAILURE (Status))
 628         {
 629             ACPI_EXCEPTION ((AE_INFO, Status,
 630                 "while evaluating GPE method [%4.4s]",
 631                 AcpiUtGetNodeName (LocalGpeEventInfo->Dispatch.MethodNode)));
 632         }
 633         break;
 634 
 635     default:
 636 
 637         return_VOID; /* Should never happen */
 638     }
 639 
 640     /* Defer enabling of GPE until all notify handlers are done */
 641 
 642     Status = AcpiOsExecute (OSL_NOTIFY_HANDLER,
 643                 AcpiEvAsynchEnableGpe, LocalGpeEventInfo);
 644     if (ACPI_FAILURE (Status))
 645     {
 646         ACPI_FREE (LocalGpeEventInfo);
 647     }
 648     return_VOID;
 649 }
 650 
 651 
 652 /*******************************************************************************
 653  *
 654  * FUNCTION:    AcpiEvAsynchEnableGpe
 655  *
 656  * PARAMETERS:  Context (GpeEventInfo) - Info for this GPE
 657  *              Callback from AcpiOsExecute
 658  *
 659  * RETURN:      None
 660  *
 661  * DESCRIPTION: Asynchronous clear/enable for GPE. This allows the GPE to
 662  *              complete (i.e., finish execution of Notify)
 663  *
 664  ******************************************************************************/
 665 
 666 static void ACPI_SYSTEM_XFACE
 667 AcpiEvAsynchEnableGpe (
 668     void                    *Context)
 669 {
 670     ACPI_GPE_EVENT_INFO     *GpeEventInfo = Context;
 671 
 672 
 673     (void) AcpiEvFinishGpe (GpeEventInfo);
 674 
 675     ACPI_FREE (GpeEventInfo);
 676     return;
 677 }
 678 
 679 
 680 /*******************************************************************************
 681  *
 682  * FUNCTION:    AcpiEvFinishGpe
 683  *
 684  * PARAMETERS:  GpeEventInfo        - Info for this GPE
 685  *
 686  * RETURN:      Status
 687  *
 688  * DESCRIPTION: Clear/Enable a GPE. Common code that is used after execution
 689  *              of a GPE method or a synchronous or asynchronous GPE handler.
 690  *
 691  ******************************************************************************/
 692 
 693 ACPI_STATUS
 694 AcpiEvFinishGpe (
 695     ACPI_GPE_EVENT_INFO     *GpeEventInfo)
 696 {
 697     ACPI_STATUS             Status;
 698 
 699 
 700     if ((GpeEventInfo->Flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
 701             ACPI_GPE_LEVEL_TRIGGERED)
 702     {
 703         /*
 704          * GPE is level-triggered, we clear the GPE status bit after
 705          * handling the event.
 706          */
 707         Status = AcpiHwClearGpe (GpeEventInfo);
 708         if (ACPI_FAILURE (Status))
 709         {
 710             return (Status);
 711         }
 712     }
 713 
 714     /*
 715      * Enable this GPE, conditionally. This means that the GPE will
 716      * only be physically enabled if the EnableForRun bit is set
 717      * in the EventInfo.
 718      */
 719     (void) AcpiHwLowSetGpe (GpeEventInfo, ACPI_GPE_CONDITIONAL_ENABLE);
 720     return (AE_OK);
 721 }
 722 
 723 
 724 /*******************************************************************************
 725  *
 726  * FUNCTION:    AcpiEvGpeDispatch
 727  *
 728  * PARAMETERS:  GpeDevice           - Device node. NULL for GPE0/GPE1
 729  *              GpeEventInfo        - Info for this GPE
 730  *              GpeNumber           - Number relative to the parent GPE block
 731  *
 732  * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
 733  *
 734  * DESCRIPTION: Dispatch a General Purpose Event to either a function (e.g. EC)
 735  *              or method (e.g. _Lxx/_Exx) handler.
 736  *
 737  *              This function executes at interrupt level.
 738  *
 739  ******************************************************************************/
 740 
 741 UINT32
 742 AcpiEvGpeDispatch (
 743     ACPI_NAMESPACE_NODE     *GpeDevice,
 744     ACPI_GPE_EVENT_INFO     *GpeEventInfo,
 745     UINT32                  GpeNumber)
 746 {
 747     ACPI_STATUS             Status;
 748     UINT32                  ReturnValue;
 749 
 750 
 751     ACPI_FUNCTION_TRACE (EvGpeDispatch);
 752 
 753 
 754     /* Invoke global event handler if present */
 755 
 756     AcpiGpeCount++;
 757     if (AcpiGbl_GlobalEventHandler)
 758     {
 759         AcpiGbl_GlobalEventHandler (ACPI_EVENT_TYPE_GPE, GpeDevice,
 760              GpeNumber, AcpiGbl_GlobalEventHandlerContext);
 761     }
 762 
 763     /*
 764      * If edge-triggered, clear the GPE status bit now. Note that
 765      * level-triggered events are cleared after the GPE is serviced.
 766      */
 767     if ((GpeEventInfo->Flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
 768             ACPI_GPE_EDGE_TRIGGERED)
 769     {
 770         Status = AcpiHwClearGpe (GpeEventInfo);
 771         if (ACPI_FAILURE (Status))
 772         {
 773             ACPI_EXCEPTION ((AE_INFO, Status,
 774                 "Unable to clear GPE%02X", GpeNumber));
 775             return_UINT32 (ACPI_INTERRUPT_NOT_HANDLED);
 776         }
 777     }
 778 
 779     /*
 780      * Always disable the GPE so that it does not keep firing before
 781      * any asynchronous activity completes (either from the execution
 782      * of a GPE method or an asynchronous GPE handler.)
 783      *
 784      * If there is no handler or method to run, just disable the
 785      * GPE and leave it disabled permanently to prevent further such
 786      * pointless events from firing.
 787      */
 788     Status = AcpiHwLowSetGpe (GpeEventInfo, ACPI_GPE_DISABLE);
 789     if (ACPI_FAILURE (Status))
 790     {
 791         ACPI_EXCEPTION ((AE_INFO, Status,
 792             "Unable to disable GPE%02X", GpeNumber));
 793         return_UINT32 (ACPI_INTERRUPT_NOT_HANDLED);
 794     }
 795 
 796     /*
 797      * Dispatch the GPE to either an installed handler or the control
 798      * method associated with this GPE (_Lxx or _Exx). If a handler
 799      * exists, we invoke it and do not attempt to run the method.
 800      * If there is neither a handler nor a method, leave the GPE
 801      * disabled.
 802      */
 803     switch (GpeEventInfo->Flags & ACPI_GPE_DISPATCH_MASK)
 804     {
 805     case ACPI_GPE_DISPATCH_HANDLER:
 806 
 807         /* Invoke the installed handler (at interrupt level) */
 808 
 809         ReturnValue = GpeEventInfo->Dispatch.Handler->Address (
 810             GpeDevice, GpeNumber,
 811             GpeEventInfo->Dispatch.Handler->Context);
 812 
 813         /* If requested, clear (if level-triggered) and reenable the GPE */
 814 
 815         if (ReturnValue & ACPI_REENABLE_GPE)
 816         {
 817             (void) AcpiEvFinishGpe (GpeEventInfo);
 818         }
 819         break;
 820 
 821     case ACPI_GPE_DISPATCH_METHOD:
 822     case ACPI_GPE_DISPATCH_NOTIFY:
 823         /*
 824          * Execute the method associated with the GPE
 825          * NOTE: Level-triggered GPEs are cleared after the method completes.
 826          */
 827         Status = AcpiOsExecute (OSL_GPE_HANDLER,
 828                     AcpiEvAsynchExecuteGpeMethod, GpeEventInfo);
 829         if (ACPI_FAILURE (Status))
 830         {
 831             ACPI_EXCEPTION ((AE_INFO, Status,
 832                 "Unable to queue handler for GPE%02X - event disabled",
 833                 GpeNumber));
 834         }
 835         break;
 836 
 837     default:
 838         /*
 839          * No handler or method to run!
 840          * 03/2010: This case should no longer be possible. We will not allow
 841          * a GPE to be enabled if it has no handler or method.
 842          */
 843         ACPI_ERROR ((AE_INFO,
 844             "No handler or method for GPE%02X, disabling event",
 845             GpeNumber));
 846         break;
 847     }
 848 
 849     return_UINT32 (ACPI_INTERRUPT_HANDLED);
 850 }
 851 
 852 #endif /* !ACPI_REDUCED_HARDWARE */