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/******************************************************************************

 *

 * Module Name: evgpe - General Purpose Event handling and dispatch

 *

 *****************************************************************************/

/******************************************************************************

 *

 * 1. Copyright Notice

 *

 * Some or all of this work - Copyright (c) 1999 - 2011, Intel Corp.

 * All rights reserved.

 *

 * 2. License

 *

 * 2.1. This is your license from Intel Corp. under its intellectual property

 * rights.  You may have additional license terms from the party that provided

 * you this software, covering your right to use that party's intellectual

 * property rights.

 *

 * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a

 * copy of the source code appearing in this file ("Covered Code") an

 * irrevocable, perpetual, worldwide license under Intel's copyrights in the

 * base code distributed originally by Intel ("Original Intel Code") to copy,

 * make derivatives, distribute, use and display any portion of the Covered

 * Code in any form, with the right to sublicense such rights; and

 *

 * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent

 * license (with the right to sublicense), under only those claims of Intel

 * patents that are infringed by the Original Intel Code, to make, use, sell,

 * offer to sell, and import the Covered Code and derivative works thereof

 * solely to the minimum extent necessary to exercise the above copyright

 * license, and in no event shall the patent license extend to any additions

 * to or modifications of the Original Intel Code.  No other license or right

 * is granted directly or by implication, estoppel or otherwise;

 *

 * The above copyright and patent license is granted only if the following

 * conditions are met:

 *

 * 3. Conditions

 *

 * 3.1. Redistribution of Source with Rights to Further Distribute Source.

 * Redistribution of source code of any substantial portion of the Covered

 * Code or modification with rights to further distribute source must include

 * the above Copyright Notice, the above License, this list of Conditions,

 * and the following Disclaimer and Export Compliance provision.  In addition,

 * Licensee must cause all Covered Code to which Licensee contributes to

 * contain a file documenting the changes Licensee made to create that Covered

 * Code and the date of any change.  Licensee must include in that file the

 * documentation of any changes made by any predecessor Licensee.  Licensee

 * must include a prominent statement that the modification is derived,

 * directly or indirectly, from Original Intel Code.

 *

 * 3.2. Redistribution of Source with no Rights to Further Distribute Source.

 * Redistribution of source code of any substantial portion of the Covered

 * Code or modification without rights to further distribute source must

 * include the following Disclaimer and Export Compliance provision in the

 * documentation and/or other materials provided with distribution.  In

 * addition, Licensee may not authorize further sublicense of source of any

 * portion of the Covered Code, and must include terms to the effect that the

 * license from Licensee to its licensee is limited to the intellectual

 * property embodied in the software Licensee provides to its licensee, and

 * not to intellectual property embodied in modifications its licensee may

 * make.

 *

 * 3.3. Redistribution of Executable. Redistribution in executable form of any

 * substantial portion of the Covered Code or modification must reproduce the

 * above Copyright Notice, and the following Disclaimer and Export Compliance

 * provision in the documentation and/or other materials provided with the

 * distribution.

 *

 * 3.4. Intel retains all right, title, and interest in and to the Original

 * Intel Code.

 *

 * 3.5. Neither the name Intel nor any other trademark owned or controlled by

 * Intel shall be used in advertising or otherwise to promote the sale, use or

 * other dealings in products derived from or relating to the Covered Code

 * without prior written authorization from Intel.

 *

 * 4. Disclaimer and Export Compliance

 *

 * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED

 * HERE.  ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE

 * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT,  ASSISTANCE,

 * INSTALLATION, TRAINING OR OTHER SERVICES.  INTEL WILL NOT PROVIDE ANY

 * UPDATES, ENHANCEMENTS OR EXTENSIONS.  INTEL SPECIFICALLY DISCLAIMS ANY

 * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A

 * PARTICULAR PURPOSE.

 *

 * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES

 * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR

 * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,

 * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY

 * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL

 * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.  THESE LIMITATIONS

 * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY

 * LIMITED REMEDY.

 *

 * 4.3. Licensee shall not export, either directly or indirectly, any of this

 * software or system incorporating such software without first obtaining any

 * required license or other approval from the U. S. Department of Commerce or

 * any other agency or department of the United States Government.  In the

 * event Licensee exports any such software from the United States or

 * re-exports any such software from a foreign destination, Licensee shall

 * ensure that the distribution and export/re-export of the software is in

 * compliance with all laws, regulations, orders, or other restrictions of the

 * U.S. Export Administration Regulations. Licensee agrees that neither it nor

 * any of its subsidiaries will export/re-export any technical data, process,

 * software, or service, directly or indirectly, to any country for which the

 * United States government or any agency thereof requires an export license,

 * other governmental approval, or letter of assurance, without first obtaining

 * such license, approval or letter.

 *

 *****************************************************************************/

#include "acpi.h"

#include "accommon.h"

#include "acevents.h"

#include "acnamesp.h"

#define _COMPONENT          ACPI_EVENTS

        ACPI_MODULE_NAME    ("evgpe")

/* Local prototypes */

static void ACPI_SYSTEM_XFACE

AcpiEvAsynchExecuteGpeMethod (

    void                    *Context);

static void ACPI_SYSTEM_XFACE

AcpiEvAsynchEnableGpe (

    void                    *Context);

/*******************************************************************************

 *

 * FUNCTION:    AcpiEvUpdateGpeEnableMask

 *

 * PARAMETERS:  GpeEventInfo            - GPE to update

 *

 * RETURN:      Status

 *

 * DESCRIPTION: Updates GPE register enable mask based upon whether there are

 *              runtime references to this GPE

 *

 ******************************************************************************/

ACPI_STATUS

AcpiEvUpdateGpeEnableMask (

    ACPI_GPE_EVENT_INFO     *GpeEventInfo)

{

    ACPI_GPE_REGISTER_INFO  *GpeRegisterInfo;

    UINT32                  RegisterBit;

    ACPI_FUNCTION_TRACE (EvUpdateGpeEnableMask);

    GpeRegisterInfo = GpeEventInfo->RegisterInfo;

    if (!GpeRegisterInfo)

    {

        return_ACPI_STATUS (AE_NOT_EXIST);

    }

    RegisterBit = AcpiHwGetGpeRegisterBit (GpeEventInfo, GpeRegisterInfo);

    /* Clear the run bit up front */

    ACPI_CLEAR_BIT (GpeRegisterInfo->EnableForRun, RegisterBit);

    /* Set the mask bit only if there are references to this GPE */

    if (GpeEventInfo->RuntimeCount)

    {

        ACPI_SET_BIT (GpeRegisterInfo->EnableForRun, (UINT8) RegisterBit);

    }

    return_ACPI_STATUS (AE_OK);

}

/*******************************************************************************

 *

 * FUNCTION:    AcpiEvEnableGpe

 *

 * PARAMETERS:  GpeEventInfo            - GPE to enable

 *

 * RETURN:      Status

 *

 * DESCRIPTION: Clear a GPE of stale events and enable it.

 *

 ******************************************************************************/

ACPI_STATUS

AcpiEvEnableGpe (

    ACPI_GPE_EVENT_INFO     *GpeEventInfo)

{

    ACPI_STATUS             Status;

    ACPI_FUNCTION_TRACE (EvEnableGpe);

    /*

     * We will only allow a GPE to be enabled if it has either an associated

     * method (_Lxx/_Exx) or a handler, or is using the implicit notify

     * feature. Otherwise, the GPE will be immediately disabled by

     * AcpiEvGpeDispatch the first time it fires.

     */

    if ((GpeEventInfo->Flags & ACPI_GPE_DISPATCH_MASK) ==

        ACPI_GPE_DISPATCH_NONE)

    {

        return_ACPI_STATUS (AE_NO_HANDLER);

    }

    /* Clear the GPE (of stale events) */

    Status = AcpiHwClearGpe (GpeEventInfo);

    if (ACPI_FAILURE (Status))

    {

        return_ACPI_STATUS (Status);

    }

    /* Enable the requested GPE */

    Status = AcpiHwLowSetGpe (GpeEventInfo, ACPI_GPE_ENABLE);

    return_ACPI_STATUS (Status);

}

/*******************************************************************************

 *

 * FUNCTION:    AcpiEvAddGpeReference

 *

 * PARAMETERS:  GpeEventInfo            - Add a reference to this GPE

 *

 * RETURN:      Status

 *

 * DESCRIPTION: Add a reference to a GPE. On the first reference, the GPE is

 *              hardware-enabled.

 *

 ******************************************************************************/

ACPI_STATUS

AcpiEvAddGpeReference (

    ACPI_GPE_EVENT_INFO     *GpeEventInfo)

{

    ACPI_STATUS             Status = AE_OK;

    ACPI_FUNCTION_TRACE (EvAddGpeReference);

    if (GpeEventInfo->RuntimeCount == ACPI_UINT8_MAX)

    {

        return_ACPI_STATUS (AE_LIMIT);

    }

    GpeEventInfo->RuntimeCount++;

    if (GpeEventInfo->RuntimeCount == 1)

    {

        /* Enable on first reference */

        Status = AcpiEvUpdateGpeEnableMask (GpeEventInfo);

        if (ACPI_SUCCESS (Status))

        {

            Status = AcpiEvEnableGpe (GpeEventInfo);

        }

        if (ACPI_FAILURE (Status))

        {

            GpeEventInfo->RuntimeCount--;

        }

    }

    return_ACPI_STATUS (Status);

}

/*******************************************************************************

 *

 * FUNCTION:    AcpiEvRemoveGpeReference

 *

 * PARAMETERS:  GpeEventInfo            - Remove a reference to this GPE

 *

 * RETURN:      Status

 *

 * DESCRIPTION: Remove a reference to a GPE. When the last reference is

 *              removed, the GPE is hardware-disabled.

 *

 ******************************************************************************/

ACPI_STATUS

AcpiEvRemoveGpeReference (

    ACPI_GPE_EVENT_INFO     *GpeEventInfo)

{

    ACPI_STATUS             Status = AE_OK;

    ACPI_FUNCTION_TRACE (EvRemoveGpeReference);

    if (!GpeEventInfo->RuntimeCount)

    {

        return_ACPI_STATUS (AE_LIMIT);

    }

    GpeEventInfo->RuntimeCount--;

    if (!GpeEventInfo->RuntimeCount)

    {

        /* Disable on last reference */

        Status = AcpiEvUpdateGpeEnableMask (GpeEventInfo);

        if (ACPI_SUCCESS (Status))

        {

            Status = AcpiHwLowSetGpe (GpeEventInfo, ACPI_GPE_DISABLE);

        }

        if (ACPI_FAILURE (Status))

        {

            GpeEventInfo->RuntimeCount++;

        }

    }

    return_ACPI_STATUS (Status);

}

/*******************************************************************************

 *

 * FUNCTION:    AcpiEvLowGetGpeInfo

 *

 * PARAMETERS:  GpeNumber           - Raw GPE number

 *              GpeBlock            - A GPE info block

 *

 * RETURN:      A GPE EventInfo struct. NULL if not a valid GPE (The GpeNumber

 *              is not within the specified GPE block)

 *

 * DESCRIPTION: Returns the EventInfo struct associated with this GPE. This is

 *              the low-level implementation of EvGetGpeEventInfo.

 *

 ******************************************************************************/

ACPI_GPE_EVENT_INFO *

AcpiEvLowGetGpeInfo (

    UINT32                  GpeNumber,

    ACPI_GPE_BLOCK_INFO     *GpeBlock)

{

    UINT32                  GpeIndex;

    /*

     * Validate that the GpeNumber is within the specified GpeBlock.

     * (Two steps)

     */

    if (!GpeBlock ||

        (GpeNumber < GpeBlock->BlockBaseNumber))

    {

        return (NULL);

    }

    GpeIndex = GpeNumber - GpeBlock->BlockBaseNumber;

    if (GpeIndex >= GpeBlock->GpeCount)

    {

        return (NULL);

    }

    return (&GpeBlock->EventInfo[GpeIndex]);

}

/*******************************************************************************

 *

 * FUNCTION:    AcpiEvGetGpeEventInfo

 *

 * PARAMETERS:  GpeDevice           - Device node. NULL for GPE0/GPE1

 *              GpeNumber           - Raw GPE number

 *

 * RETURN:      A GPE EventInfo struct. NULL if not a valid GPE

 *

 * DESCRIPTION: Returns the EventInfo struct associated with this GPE.

 *              Validates the GpeBlock and the GpeNumber

 *

 *              Should be called only when the GPE lists are semaphore locked

 *              and not subject to change.

 *

 ******************************************************************************/

ACPI_GPE_EVENT_INFO *

AcpiEvGetGpeEventInfo (

    ACPI_HANDLE             GpeDevice,

    UINT32                  GpeNumber)

{

    ACPI_OPERAND_OBJECT     *ObjDesc;

    ACPI_GPE_EVENT_INFO     *GpeInfo;

    UINT32                  i;

    ACPI_FUNCTION_ENTRY ();

    /* A NULL GpeDevice means use the FADT-defined GPE block(s) */

    if (!GpeDevice)

    {

        /* Examine GPE Block 0 and 1 (These blocks are permanent) */

        for (i = 0; i < ACPI_MAX_GPE_BLOCKS; i++)

        {

            GpeInfo = AcpiEvLowGetGpeInfo (GpeNumber,

                        AcpiGbl_GpeFadtBlocks[i]);

            if (GpeInfo)

            {

                return (GpeInfo);

            }

        }

        /* The GpeNumber was not in the range of either FADT GPE block */

        return (NULL);

    }

    /* A Non-NULL GpeDevice means this is a GPE Block Device */

    ObjDesc = AcpiNsGetAttachedObject ((ACPI_NAMESPACE_NODE *) GpeDevice);

    if (!ObjDesc ||

        !ObjDesc->Device.GpeBlock)

    {

        return (NULL);

    }

    return (AcpiEvLowGetGpeInfo (GpeNumber, ObjDesc->Device.GpeBlock));

}

/*******************************************************************************

 *

 * FUNCTION:    AcpiEvGpeDetect

 *

 * PARAMETERS:  GpeXruptList        - Interrupt block for this interrupt.

 *                                    Can have multiple GPE blocks attached.

 *

 * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED

 *

 * DESCRIPTION: Detect if any GP events have occurred. This function is

 *              executed at interrupt level.

 *

 ******************************************************************************/

UINT32

AcpiEvGpeDetect (

    ACPI_GPE_XRUPT_INFO     *GpeXruptList)

{

    ACPI_STATUS             Status;

    ACPI_GPE_BLOCK_INFO     *GpeBlock;

    ACPI_GPE_REGISTER_INFO  *GpeRegisterInfo;

    UINT32                  IntStatus = ACPI_INTERRUPT_NOT_HANDLED;

    UINT8                   EnabledStatusByte;

    UINT32                  StatusReg;

    UINT32                  EnableReg;

    ACPI_CPU_FLAGS          Flags;

    UINT32                  i;

    UINT32                  j;

    ACPI_FUNCTION_NAME (EvGpeDetect);

    /* Check for the case where there are no GPEs */

    if (!GpeXruptList)

    {

        return (IntStatus);

    }

    /*

     * We need to obtain the GPE lock for both the data structs and registers

     * Note: Not necessary to obtain the hardware lock, since the GPE

     * registers are owned by the GpeLock.

     */

    Flags = AcpiOsAcquireLock (AcpiGbl_GpeLock);

    /* Examine all GPE blocks attached to this interrupt level */

    GpeBlock = GpeXruptList->GpeBlockListHead;

    while (GpeBlock)

    {

        /*

         * Read all of the 8-bit GPE status and enable registers in this GPE

         * block, saving all of them. Find all currently active GP events.

         */

        for (i = 0; i < GpeBlock->RegisterCount; i++)

        {

            /* Get the next status/enable pair */

            GpeRegisterInfo = &GpeBlock->RegisterInfo[i];

            /*

             * Optimization: If there are no GPEs enabled within this

             * register, we can safely ignore the entire register.

             */

            if (!(GpeRegisterInfo->EnableForRun |

                  GpeRegisterInfo->EnableForWake))

            {

                continue;

            }

            /* Read the Status Register */

            Status = AcpiHwRead (&StatusReg, &GpeRegisterInfo->StatusAddress);

            if (ACPI_FAILURE (Status))

            {

                goto UnlockAndExit;

            }

            /* Read the Enable Register */

            Status = AcpiHwRead (&EnableReg, &GpeRegisterInfo->EnableAddress);

            if (ACPI_FAILURE (Status))

            {

                goto UnlockAndExit;

            }

            ACPI_DEBUG_PRINT ((ACPI_DB_INTERRUPTS,

                "Read GPE Register at GPE%02X: Status=%02X, Enable=%02X\n",

                GpeRegisterInfo->BaseGpeNumber, StatusReg, EnableReg));

            /* Check if there is anything active at all in this register */

            EnabledStatusByte = (UINT8) (StatusReg & EnableReg);

            if (!EnabledStatusByte)

            {

                /* No active GPEs in this register, move on */

                continue;

            }

            /* Now look at the individual GPEs in this byte register */

            for (j = 0; j < ACPI_GPE_REGISTER_WIDTH; j++)

            {

                /* Examine one GPE bit */

                if (EnabledStatusByte & (1 << j))

                {

                    /*

                     * Found an active GPE. Dispatch the event to a handler

                     * or method.

                     */

                    IntStatus |= AcpiEvGpeDispatch (GpeBlock->Node,

                        &GpeBlock->EventInfo[((ACPI_SIZE) i *

                            ACPI_GPE_REGISTER_WIDTH) + j],

                        j + GpeRegisterInfo->BaseGpeNumber);

                }

            }

        }

        GpeBlock = GpeBlock->Next;

    }

UnlockAndExit:

    AcpiOsReleaseLock (AcpiGbl_GpeLock, Flags);

    return (IntStatus);

}

/*******************************************************************************

 *

 * FUNCTION:    AcpiEvAsynchExecuteGpeMethod

 *

 * PARAMETERS:  Context (GpeEventInfo) - Info for this GPE

 *

 * RETURN:      None

 *

 * DESCRIPTION: Perform the actual execution of a GPE control method. This

 *              function is called from an invocation of AcpiOsExecute and

 *              therefore does NOT execute at interrupt level - so that

 *              the control method itself is not executed in the context of

 *              an interrupt handler.

 *

 ******************************************************************************/

static void ACPI_SYSTEM_XFACE

AcpiEvAsynchExecuteGpeMethod (

    void                    *Context)

{

    ACPI_GPE_EVENT_INFO     *GpeEventInfo = Context;

    ACPI_STATUS             Status;

    ACPI_GPE_EVENT_INFO     *LocalGpeEventInfo;

    ACPI_EVALUATE_INFO      *Info;

    ACPI_FUNCTION_TRACE (EvAsynchExecuteGpeMethod);

    /* Allocate a local GPE block */

    LocalGpeEventInfo = ACPI_ALLOCATE_ZEROED (sizeof (ACPI_GPE_EVENT_INFO));

    if (!LocalGpeEventInfo)

    {

        ACPI_EXCEPTION ((AE_INFO, AE_NO_MEMORY,

            "while handling a GPE"));

        return_VOID;

    }

    Status = AcpiUtAcquireMutex (ACPI_MTX_EVENTS);

    if (ACPI_FAILURE (Status))

    {

        return_VOID;

    }

    /* Must revalidate the GpeNumber/GpeBlock */

    if (!AcpiEvValidGpeEvent (GpeEventInfo))

    {

        Status = AcpiUtReleaseMutex (ACPI_MTX_EVENTS);

        return_VOID;

    }

    /*

     * Take a snapshot of the GPE info for this level - we copy the info to

     * prevent a race condition with RemoveHandler/RemoveBlock.

     */

    ACPI_MEMCPY (LocalGpeEventInfo, GpeEventInfo,

        sizeof (ACPI_GPE_EVENT_INFO));

    Status = AcpiUtReleaseMutex (ACPI_MTX_EVENTS);

    if (ACPI_FAILURE (Status))

    {

        return_VOID;

    }

    /* Do the correct dispatch - normal method or implicit notify */

    switch (LocalGpeEventInfo->Flags & ACPI_GPE_DISPATCH_MASK)

    {

    case ACPI_GPE_DISPATCH_NOTIFY:

        /*

         * Implicit notify.

         * Dispatch a DEVICE_WAKE notify to the appropriate handler.

         * NOTE: the request is queued for execution after this method

         * completes. The notify handlers are NOT invoked synchronously

         * from this thread -- because handlers may in turn run other

         * control methods.

         */

        Status = AcpiEvQueueNotifyRequest (

                    LocalGpeEventInfo->Dispatch.DeviceNode,

                    ACPI_NOTIFY_DEVICE_WAKE);

        break;

    case ACPI_GPE_DISPATCH_METHOD:

        /* Allocate the evaluation information block */

        Info = ACPI_ALLOCATE_ZEROED (sizeof (ACPI_EVALUATE_INFO));

        if (!Info)

        {

            Status = AE_NO_MEMORY;

        }

        else

        {

            /*

             * Invoke the GPE Method (_Lxx, _Exx) i.e., evaluate the

             * _Lxx/_Exx control method that corresponds to this GPE

             */

            Info->PrefixNode = LocalGpeEventInfo->Dispatch.MethodNode;

            Info->Flags = ACPI_IGNORE_RETURN_VALUE;

            Status = AcpiNsEvaluate (Info);

            ACPI_FREE (Info);

        }

        if (ACPI_FAILURE (Status))

        {

            ACPI_EXCEPTION ((AE_INFO, Status,

                "while evaluating GPE method [%4.4s]",

                AcpiUtGetNodeName (LocalGpeEventInfo->Dispatch.MethodNode)));

        }

        break;

    default:

        return_VOID; /* Should never happen */

    }

    /* Defer enabling of GPE until all notify handlers are done */

    Status = AcpiOsExecute (OSL_NOTIFY_HANDLER,

                AcpiEvAsynchEnableGpe, LocalGpeEventInfo);

    if (ACPI_FAILURE (Status))

    {

        ACPI_FREE (LocalGpeEventInfo);

    }

    return_VOID;

}

/*******************************************************************************

 *

 * FUNCTION:    AcpiEvAsynchEnableGpe

 *

 * PARAMETERS:  Context (GpeEventInfo) - Info for this GPE

 *              Callback from AcpiOsExecute

 *

 * RETURN:      None

 *

 * DESCRIPTION: Asynchronous clear/enable for GPE. This allows the GPE to

 *              complete (i.e., finish execution of Notify)

 *

 ******************************************************************************/

static void ACPI_SYSTEM_XFACE

AcpiEvAsynchEnableGpe (

    void                    *Context)

{

    ACPI_GPE_EVENT_INFO     *GpeEventInfo = Context;

    (void) AcpiEvFinishGpe (GpeEventInfo);

    ACPI_FREE (GpeEventInfo);

    return;

}

/*******************************************************************************

 *

 * FUNCTION:    AcpiEvFinishGpe

 *

 * PARAMETERS:  GpeEventInfo        - Info for this GPE

 *

 * RETURN:      Status

 *

 * DESCRIPTION: Clear/Enable a GPE. Common code that is used after execution

 *              of a GPE method or a synchronous or asynchronous GPE handler.

 *

 ******************************************************************************/

ACPI_STATUS

AcpiEvFinishGpe (

    ACPI_GPE_EVENT_INFO     *GpeEventInfo)

{

    ACPI_STATUS             Status;

    if ((GpeEventInfo->Flags & ACPI_GPE_XRUPT_TYPE_MASK) ==

            ACPI_GPE_LEVEL_TRIGGERED)

    {

        /*

         * GPE is level-triggered, we clear the GPE status bit after

         * handling the event.

         */

        Status = AcpiHwClearGpe (GpeEventInfo);

        if (ACPI_FAILURE (Status))

        {

            return (Status);

        }

    }

    /*

     * Enable this GPE, conditionally. This means that the GPE will

     * only be physically enabled if the EnableForRun bit is set

     * in the EventInfo.

     */

    (void) AcpiHwLowSetGpe (GpeEventInfo, ACPI_GPE_CONDITIONAL_ENABLE);

    return (AE_OK);

}

/*******************************************************************************

 *

 * FUNCTION:    AcpiEvGpeDispatch

 *

 * PARAMETERS:  GpeDevice           - Device node. NULL for GPE0/GPE1

 *              GpeEventInfo        - Info for this GPE

 *              GpeNumber           - Number relative to the parent GPE block

 *

 * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED

 *

 * DESCRIPTION: Dispatch a General Purpose Event to either a function (e.g. EC)

 *              or method (e.g. _Lxx/_Exx) handler.

 *

 *              This function executes at interrupt level.

 *

 ******************************************************************************/

UINT32

AcpiEvGpeDispatch (

    ACPI_NAMESPACE_NODE     *GpeDevice,

    ACPI_GPE_EVENT_INFO     *GpeEventInfo,

    UINT32                  GpeNumber)

{

    ACPI_STATUS             Status;

    UINT32                  ReturnValue;

    ACPI_FUNCTION_TRACE (EvGpeDispatch);

    /* Invoke global event handler if present */

    AcpiGpeCount++;

    if (AcpiGbl_GlobalEventHandler)

    {

        AcpiGbl_GlobalEventHandler (ACPI_EVENT_TYPE_GPE, GpeDevice,

             GpeNumber, AcpiGbl_GlobalEventHandlerContext);

    }

    /*

     * If edge-triggered, clear the GPE status bit now. Note that

     * level-triggered events are cleared after the GPE is serviced.

     */

    if ((GpeEventInfo->Flags & ACPI_GPE_XRUPT_TYPE_MASK) ==

            ACPI_GPE_EDGE_TRIGGERED)

    {

        Status = AcpiHwClearGpe (GpeEventInfo);

        if (ACPI_FAILURE (Status))

        {

            ACPI_EXCEPTION ((AE_INFO, Status,

                "Unable to clear GPE%02X", GpeNumber));

            return_UINT32 (ACPI_INTERRUPT_NOT_HANDLED);

        }

    }

    /*

     * Always disable the GPE so that it does not keep firing before

     * any asynchronous activity completes (either from the execution

     * of a GPE method or an asynchronous GPE handler.)

     *

     * If there is no handler or method to run, just disable the

     * GPE and leave it disabled permanently to prevent further such

     * pointless events from firing.

     */

    Status = AcpiHwLowSetGpe (GpeEventInfo, ACPI_GPE_DISABLE);

    if (ACPI_FAILURE (Status))

    {

        ACPI_EXCEPTION ((AE_INFO, Status,

            "Unable to disable GPE%02X", GpeNumber));

        return_UINT32 (ACPI_INTERRUPT_NOT_HANDLED);

    }

    /*

     * Dispatch the GPE to either an installed handler or the control

     * method associated with this GPE (_Lxx or _Exx). If a handler

     * exists, we invoke it and do not attempt to run the method.

     * If there is neither a handler nor a method, leave the GPE

     * disabled.

     */

    switch (GpeEventInfo->Flags & ACPI_GPE_DISPATCH_MASK)

    {

    case ACPI_GPE_DISPATCH_HANDLER:

        /* Invoke the installed handler (at interrupt level) */

        ReturnValue = GpeEventInfo->Dispatch.Handler->Address (

            GpeDevice, GpeNumber,

            GpeEventInfo->Dispatch.Handler->Context);

        /* If requested, clear (if level-triggered) and reenable the GPE */

        if (ReturnValue & ACPI_REENABLE_GPE)

        {

            (void) AcpiEvFinishGpe (GpeEventInfo);

        }

        break;

    case ACPI_GPE_DISPATCH_METHOD:

    case ACPI_GPE_DISPATCH_NOTIFY:

        /*

         * Execute the method associated with the GPE

         * NOTE: Level-triggered GPEs are cleared after the method completes.

         */

        Status = AcpiOsExecute (OSL_GPE_HANDLER,

                    AcpiEvAsynchExecuteGpeMethod, GpeEventInfo);

        if (ACPI_FAILURE (Status))

        {

            ACPI_EXCEPTION ((AE_INFO, Status,

                "Unable to queue handler for GPE%02X - event disabled",

                GpeNumber));

        }

        break;

    default:

        /*

         * No handler or method to run!

         * 03/2010: This case should no longer be possible. We will not allow

         * a GPE to be enabled if it has no handler or method.

         */

        ACPI_ERROR ((AE_INFO,

            "No handler or method for GPE%02X, disabling event",

            GpeNumber));

        break;

    }

    return_UINT32 (ACPI_INTERRUPT_HANDLED);

}