evregion.c

acpi tools for linux include acpiexec and acpixtract

    RegionObj2 = AcpiNsGetSecondaryObject (RegionObj);
    if (!RegionObj2)
    {
        return_ACPI_STATUS (AE_NOT_EXIST);
    }

    /* Ensure that there is a handler associated with this region */

    HandlerDesc = RegionObj->Region.Handler;
    if (!HandlerDesc)
    {
        ACPI_ERROR ((AE_INFO,
            "No handler for Region [%4.4s] (%p) [%s]",
            AcpiUtGetNodeName (RegionObj->Region.Node),
            RegionObj, AcpiUtGetRegionName (RegionObj->Region.SpaceId)));

        return_ACPI_STATUS (AE_NOT_EXIST);
    }

    /*
     * It may be the case that the region has never been initialized
     * Some types of regions require special init code
     */
    if (!(RegionObj->Region.Flags & AOPOBJ_SETUP_COMPLETE))
    {
        /*
         * This region has not been initialized yet, do it
         */
        RegionSetup = HandlerDesc->AddressSpace.Setup;
        if (!RegionSetup)
        {
            /* No initialization routine, exit with error */

            ACPI_ERROR ((AE_INFO,
                "No init routine for region(%p) [%s]",
                RegionObj, AcpiUtGetRegionName (RegionObj->Region.SpaceId)));
            return_ACPI_STATUS (AE_NOT_EXIST);
        }

        /*
         * We must exit the interpreter because the region
         * setup will potentially execute control methods
         * (e.g., _REG method for this region)
         */
        AcpiExExitInterpreter ();

        Status = RegionSetup (RegionObj, ACPI_REGION_ACTIVATE,
                    HandlerDesc->AddressSpace.Context, &RegionContext);

        /* Re-enter the interpreter */

        AcpiExEnterInterpreter ();

        /* Check for failure of the Region Setup */

        if (ACPI_FAILURE (Status))
        {
            ACPI_EXCEPTION ((AE_INFO, Status,
                "During region initialization: [%s]",
                AcpiUtGetRegionName (RegionObj->Region.SpaceId)));
            return_ACPI_STATUS (Status);
        }

        /*
         * Region initialization may have been completed by RegionSetup
         */
        if (!(RegionObj->Region.Flags & AOPOBJ_SETUP_COMPLETE))
        {
            RegionObj->Region.Flags |= AOPOBJ_SETUP_COMPLETE;

            if (RegionObj2->Extra.RegionContext)
            {
                /* The handler for this region was already installed */

                ACPI_FREE (RegionContext);
            }
            else
            {
                /*
                 * Save the returned context for use in all accesses to
                 * this particular region
                 */
                RegionObj2->Extra.RegionContext = RegionContext;
            }
        }
    }

    /* We have everything we need, we can invoke the address space handler */

    Handler = HandlerDesc->AddressSpace.Handler;

    ACPI_DEBUG_PRINT ((ACPI_DB_OPREGION,
        "Handler %p (@%p) Address %8.8X%8.8X [%s]\n",
        &RegionObj->Region.Handler->AddressSpace, Handler,
        ACPI_FORMAT_NATIVE_UINT (Address),
        AcpiUtGetRegionName (RegionObj->Region.SpaceId)));

    if (!(HandlerDesc->AddressSpace.HandlerFlags &
            ACPI_ADDR_HANDLER_DEFAULT_INSTALLED))
    {
        /*
         * For handlers other than the default (supplied) handlers, we must
         * exit the interpreter because the handler *might* block -- we don't
         * know what it will do, so we can't hold the lock on the intepreter.
         */
        AcpiExExitInterpreter();
    }

    /* Call the handler */

    Status = Handler (Function, Address, BitWidth, Value,
        HandlerDesc->AddressSpace.Context, RegionObj2->Extra.RegionContext);

    if (ACPI_FAILURE (Status))
    {
        ACPI_EXCEPTION ((AE_INFO, Status, "Returned by Handler for [%s]",
            AcpiUtGetRegionName (RegionObj->Region.SpaceId)));
    }

    if (!(HandlerDesc->AddressSpace.HandlerFlags &
            ACPI_ADDR_HANDLER_DEFAULT_INSTALLED))
    {
        /*
         * We just returned from a non-default handler, we must re-enter the
         * interpreter
         */
       AcpiExEnterInterpreter ();
    }

    return_ACPI_STATUS (Status);
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiEvDetachRegion
 *
 * PARAMETERS:  RegionObj           - Region Object
 *              AcpiNsIsLocked      - Namespace Region Already Locked?
 *
 * RETURN:      None
 *
 * DESCRIPTION: Break the association between the handler and the region
 *              this is a two way association.
 *
 ******************************************************************************/

void
AcpiEvDetachRegion(
    ACPI_OPERAND_OBJECT     *RegionObj,
    BOOLEAN                 AcpiNsIsLocked)
{
    ACPI_OPERAND_OBJECT     *HandlerObj;
    ACPI_OPERAND_OBJECT     *ObjDesc;
    ACPI_OPERAND_OBJECT     **LastObjPtr;
    ACPI_ADR_SPACE_SETUP    RegionSetup;
    void                    **RegionContext;
    ACPI_OPERAND_OBJECT     *RegionObj2;
    ACPI_STATUS             Status;


    ACPI_FUNCTION_TRACE (EvDetachRegion);


    RegionObj2 = AcpiNsGetSecondaryObject (RegionObj);
    if (!RegionObj2)
    {
        return_VOID;
    }
    RegionContext = &RegionObj2->Extra.RegionContext;

    /* Get the address handler from the region object */

    HandlerObj = RegionObj->Region.Handler;
    if (!HandlerObj)
    {
        /* This region has no handler, all done */

        return_VOID;
    }

    /* Find this region in the handler's list */

    ObjDesc = HandlerObj->AddressSpace.RegionList;
    LastObjPtr = &HandlerObj->AddressSpace.RegionList;

    while (ObjDesc)
    {
        /* Is this the correct Region? */

        if (ObjDesc == RegionObj)
        {
            ACPI_DEBUG_PRINT ((ACPI_DB_OPREGION,
                "Removing Region %p from address handler %p\n",
                RegionObj, HandlerObj));

            /* This is it, remove it from the handler's list */

            *LastObjPtr = ObjDesc->Region.Next;
            ObjDesc->Region.Next = NULL;            /* Must clear field */

            if (AcpiNsIsLocked)
            {
                Status = AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
                if (ACPI_FAILURE (Status))
                {
                    return_VOID;
                }
            }

            /* Now stop region accesses by executing the _REG method */

            Status = AcpiEvExecuteRegMethod (RegionObj, 0);
            if (ACPI_FAILURE (Status))
            {
                ACPI_EXCEPTION ((AE_INFO, Status, "from region _REG, [%s]",
                    AcpiUtGetRegionName (RegionObj->Region.SpaceId)));
            }

            if (AcpiNsIsLocked)
            {
                Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
                if (ACPI_FAILURE (Status))
                {
                    return_VOID;
                }
            }

            /*
             * If the region has been activated, call the setup handler
             * with the deactivate notification
             */
            if (RegionObj->Region.Flags & AOPOBJ_SETUP_COMPLETE)
            {
                RegionSetup = HandlerObj->AddressSpace.Setup;
                Status = RegionSetup (RegionObj, ACPI_REGION_DEACTIVATE,
                    HandlerObj->AddressSpace.Context, RegionContext);

                /* Init routine may fail, Just ignore errors */

                if (ACPI_FAILURE (Status))
                {
                    ACPI_EXCEPTION ((AE_INFO, Status,
                        "from region handler - deactivate, [%s]",
                        AcpiUtGetRegionName (RegionObj->Region.SpaceId)));
                }

                RegionObj->Region.Flags &= ~(AOPOBJ_SETUP_COMPLETE);
            }

            /*
             * Remove handler reference in the region
             *
             * NOTE: this doesn't mean that the region goes away, the region
             * is just inaccessible as indicated to the _REG method
             *
             * If the region is on the handler's list, this must be the
             * region's handler
             */
            RegionObj->Region.Handler = NULL;
            AcpiUtRemoveReference (HandlerObj);

            return_VOID;
        }

        /* Walk the linked list of handlers */

        LastObjPtr = &ObjDesc->Region.Next;
        ObjDesc = ObjDesc->Region.Next;
    }

    /* If we get here, the region was not in the handler's region list */

    ACPI_DEBUG_PRINT ((ACPI_DB_OPREGION,
        "Cannot remove region %p from address handler %p\n",
        RegionObj, HandlerObj));

    return_VOID;
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiEvAttachRegion
 *
 * PARAMETERS:  HandlerObj          - Handler Object
 *              RegionObj           - Region Object
 *              AcpiNsIsLocked      - Namespace Region Already Locked?
 *
 * RETURN:      None
 *
 * DESCRIPTION: Create the association between the handler and the region
 *              this is a two way association.
 *
 ******************************************************************************/

ACPI_STATUS
AcpiEvAttachRegion (
    ACPI_OPERAND_OBJECT     *HandlerObj,
    ACPI_OPERAND_OBJECT     *RegionObj,
    BOOLEAN                 AcpiNsIsLocked)
{

    ACPI_FUNCTION_TRACE (EvAttachRegion);


    ACPI_DEBUG_PRINT ((ACPI_DB_OPREGION,
        "Adding Region [%4.4s] %p to address handler %p [%s]\n",
        AcpiUtGetNodeName (RegionObj->Region.Node),
        RegionObj, HandlerObj,
        AcpiUtGetRegionName (RegionObj->Region.SpaceId)));

    /* Link this region to the front of the handler's list */

    RegionObj->Region.Next = HandlerObj->AddressSpace.RegionList;
    HandlerObj->AddressSpace.RegionList = RegionObj;

    /* Install the region's handler */

    if (RegionObj->Region.Handler)
    {
        return_ACPI_STATUS (AE_ALREADY_EXISTS);
    }

    RegionObj->Region.Handler = HandlerObj;
    AcpiUtAddReference (HandlerObj);

    return_ACPI_STATUS (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiEvInstallHandler
 *
 * PARAMETERS:  WalkNamespace callback
 *
 * DESCRIPTION: This routine installs an address handler into objects that are
 *              of type Region or Device.
 *
 *              If the Object is a Device, and the device has a handler of
 *              the same type then the search is terminated in that branch.
 *
 *              This is because the existing handler is closer in proximity
 *              to any more regions than the one we are trying to install.
 *
 ******************************************************************************/

static ACPI_STATUS
AcpiEvInstallHandler (
    ACPI_HANDLE             ObjHandle,
    UINT32                  Level,
    void                    *Context,
    void                    **ReturnValue)
{
    ACPI_OPERAND_OBJECT     *HandlerObj;
    ACPI_OPERAND_OBJECT     *NextHandlerObj;
    ACPI_OPERAND_OBJECT     *ObjDesc;
    ACPI_NAMESPACE_NODE     *Node;
    ACPI_STATUS             Status;


    ACPI_FUNCTION_NAME (EvInstallHandler);


    HandlerObj = (ACPI_OPERAND_OBJECT  *) Context;

    /* Parameter validation */

    if (!HandlerObj)
    {
        return (AE_OK);
    }

    /* Convert and validate the device handle */

    Node = AcpiNsMapHandleToNode (ObjHandle);
    if (!Node)
    {
        return (AE_BAD_PARAMETER);
    }

    /*
     * We only care about regions.and objects
     * that are allowed to have address space handlers
     */
    if ((Node->Type != ACPI_TYPE_DEVICE) &&
        (Node->Type != ACPI_TYPE_REGION) &&
        (Node != AcpiGbl_RootNode))
    {
        return (AE_OK);
    }

    /* Check for an existing internal object */

    ObjDesc = AcpiNsGetAttachedObject (Node);
    if (!ObjDesc)
    {
        /* No object, just exit */

        return (AE_OK);
    }

    /* Devices are handled different than regions */

    if (ACPI_GET_OBJECT_TYPE (ObjDesc) == ACPI_TYPE_DEVICE)
    {
        /* Check if this Device already has a handler for this address space */

        NextHandlerObj = ObjDesc->Device.Handler;