drivers/acpi/utilities/utstate.c
/*******************************************************************************
 *
 * Module Name: utstate - state object support procedures
 *
 ******************************************************************************/

/******************************************************************************
 *
 * 1. Copyright Notice
 *
 * Some or all of this work - Copyright (c) 1999 - 2010, 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.
 *
 *****************************************************************************/


#define __UTSTATE_C__

#include "acpi.h"
#include "accommon.h"

#define _COMPONENT          ACPI_UTILITIES
        ACPI_MODULE_NAME    ("utstate")


/*******************************************************************************
 *
 * FUNCTION:    AcpiUtCreatePkgStateAndPush
 *
 * PARAMETERS:  Object          - Object to be added to the new state
 *              Action          - Increment/Decrement
 *              StateList       - List the state will be added to
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Create a new state and push it
 *
 ******************************************************************************/

ACPI_STATUS
AcpiUtCreatePkgStateAndPush (
    void                    *InternalObject,
    void                    *ExternalObject,
    UINT16                  Index,
    ACPI_GENERIC_STATE      **StateList)
{
    ACPI_GENERIC_STATE       *State;


    ACPI_FUNCTION_ENTRY ();


    State = AcpiUtCreatePkgState (InternalObject, ExternalObject, Index);
    if (!State)
    {
        return (AE_NO_MEMORY);
    }

    AcpiUtPushGenericState (StateList, State);
    return (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiUtPushGenericState
 *
 * PARAMETERS:  ListHead            - Head of the state stack
 *              State               - State object to push
 *
 * RETURN:      None
 *
 * DESCRIPTION: Push a state object onto a state stack
 *
 ******************************************************************************/

void
AcpiUtPushGenericState (
    ACPI_GENERIC_STATE      **ListHead,
    ACPI_GENERIC_STATE      *State)
{
    ACPI_FUNCTION_TRACE (UtPushGenericState);


    /* Push the state object onto the front of the list (stack) */

    State->Common.Next = *ListHead;
    *ListHead = State;

    return_VOID;
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiUtPopGenericState
 *
 * PARAMETERS:  ListHead            - Head of the state stack
 *
 * RETURN:      The popped state object
 *
 * DESCRIPTION: Pop a state object from a state stack
 *
 ******************************************************************************/

ACPI_GENERIC_STATE *
AcpiUtPopGenericState (
    ACPI_GENERIC_STATE      **ListHead)
{
    ACPI_GENERIC_STATE      *State;


    ACPI_FUNCTION_TRACE (UtPopGenericState);


    /* Remove the state object at the head of the list (stack) */

    State = *ListHead;
    if (State)
    {
        /* Update the list head */

        *ListHead = State->Common.Next;
    }

    return_PTR (State);
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiUtCreateGenericState
 *
 * PARAMETERS:  None
 *
 * RETURN:      The new state object. NULL on failure.
 *
 * DESCRIPTION: Create a generic state object.  Attempt to obtain one from
 *              the global state cache;  If none available, create a new one.
 *
 ******************************************************************************/

ACPI_GENERIC_STATE *
AcpiUtCreateGenericState (
    void)
{
    ACPI_GENERIC_STATE      *State;


    ACPI_FUNCTION_ENTRY ();


    State = AcpiOsAcquireObject (AcpiGbl_StateCache);
    if (State)
    {
        /* Initialize */
        State->Common.DescriptorType = ACPI_DESC_TYPE_STATE;
    }

    return (State);
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiUtCreateThreadState
 *
 * PARAMETERS:  None
 *
 * RETURN:      New Thread State. NULL on failure
 *
 * DESCRIPTION: Create a "Thread State" - a flavor of the generic state used
 *              to track per-thread info during method execution
 *
 ******************************************************************************/

ACPI_THREAD_STATE *
AcpiUtCreateThreadState (
    void)
{
    ACPI_GENERIC_STATE      *State;


    ACPI_FUNCTION_TRACE (UtCreateThreadState);


    /* Create the generic state object */

    State = AcpiUtCreateGenericState ();
    if (!State)
    {
        return_PTR (NULL);
    }

    /* Init fields specific to the update struct */

    State->Common.DescriptorType = ACPI_DESC_TYPE_STATE_THREAD;
    State->Thread.ThreadId = AcpiOsGetThreadId ();

    /* Check for invalid thread ID - zero is very bad, it will break things */

    if (!State->Thread.ThreadId)
    {
        ACPI_ERROR ((AE_INFO, "Invalid zero ID from AcpiOsGetThreadId"));
        State->Thread.ThreadId = (ACPI_THREAD_ID) 1;
    }

    return_PTR ((ACPI_THREAD_STATE *) State);
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiUtCreateUpdateState
 *
 * PARAMETERS:  Object          - Initial Object to be installed in the state
 *              Action          - Update action to be performed
 *
 * RETURN:      New state object, null on failure
 *
 * DESCRIPTION: Create an "Update State" - a flavor of the generic state used
 *              to update reference counts and delete complex objects such
 *              as packages.
 *
 ******************************************************************************/

ACPI_GENERIC_STATE *
AcpiUtCreateUpdateState (
    ACPI_OPERAND_OBJECT     *Object,
    UINT16                  Action)
{
    ACPI_GENERIC_STATE      *State;


    ACPI_FUNCTION_TRACE_PTR (UtCreateUpdateState, Object);


    /* Create the generic state object */

    State = AcpiUtCreateGenericState ();
    if (!State)
    {
        return_PTR (NULL);
    }

    /* Init fields specific to the update struct */

    State->Common.DescriptorType = ACPI_DESC_TYPE_STATE_UPDATE;
    State->Update.Object = Object;
    State->Update.Value = Action;

    return_PTR (State);
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiUtCreatePkgState
 *
 * PARAMETERS:  Object          - Initial Object to be installed in the state
 *              Action          - Update action to be performed
 *
 * RETURN:      New state object, null on failure
 *
 * DESCRIPTION: Create a "Package State"
 *
 ******************************************************************************/

ACPI_GENERIC_STATE *
AcpiUtCreatePkgState (
    void                    *InternalObject,
    void                    *ExternalObject,
    UINT16                  Index)
{
    ACPI_GENERIC_STATE      *State;


    ACPI_FUNCTION_TRACE_PTR (UtCreatePkgState, InternalObject);


    /* Create the generic state object */

    State = AcpiUtCreateGenericState ();
    if (!State)
    {
        return_PTR (NULL);
    }

    /* Init fields specific to the update struct */

    State->Common.DescriptorType = ACPI_DESC_TYPE_STATE_PACKAGE;
    State->Pkg.SourceObject = (ACPI_OPERAND_OBJECT *) InternalObject;
    State->Pkg.DestObject = ExternalObject;
    State->Pkg.Index= Index;
    State->Pkg.NumPackages = 1;

    return_PTR (State);
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiUtCreateControlState
 *
 * PARAMETERS:  None
 *
 * RETURN:      New state object, null on failure
 *
 * DESCRIPTION: Create a "Control State" - a flavor of the generic state used
 *              to support nested IF/WHILE constructs in the AML.
 *
 ******************************************************************************/

ACPI_GENERIC_STATE *
AcpiUtCreateControlState (
    void)
{
    ACPI_GENERIC_STATE      *State;


    ACPI_FUNCTION_TRACE (UtCreateControlState);


    /* Create the generic state object */

    State = AcpiUtCreateGenericState ();
    if (!State)
    {
        return_PTR (NULL);
    }

    /* Init fields specific to the control struct */

    State->Common.DescriptorType = ACPI_DESC_TYPE_STATE_CONTROL;
    State->Common.State = ACPI_CONTROL_CONDITIONAL_EXECUTING;

    return_PTR (State);
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiUtDeleteGenericState
 *
 * PARAMETERS:  State               - The state object to be deleted
 *
 * RETURN:      None
 *
 * DESCRIPTION: Release a state object to the state cache. NULL state objects
 *              are ignored.
 *
 ******************************************************************************/

void
AcpiUtDeleteGenericState (
    ACPI_GENERIC_STATE      *State)
{
    ACPI_FUNCTION_TRACE (UtDeleteGenericState);


    /* Ignore null state */

    if (State)
    {
        (void) AcpiOsReleaseObject (AcpiGbl_StateCache, State);
    }
    return_VOID;
}


