minix3/drivers/power/acpi/dispatcher/dsfield.c

777 lines
25 KiB
C

/******************************************************************************
*
* Module Name: dsfield - Dispatcher field routines
*
*****************************************************************************/
/******************************************************************************
*
* 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 __DSFIELD_C__
#include "acpi.h"
#include "accommon.h"
#include "amlcode.h"
#include "acdispat.h"
#include "acinterp.h"
#include "acnamesp.h"
#include "acparser.h"
#define _COMPONENT ACPI_DISPATCHER
ACPI_MODULE_NAME ("dsfield")
/* Local prototypes */
static ACPI_STATUS
AcpiDsGetFieldNames (
ACPI_CREATE_FIELD_INFO *Info,
ACPI_WALK_STATE *WalkState,
ACPI_PARSE_OBJECT *Arg);
/*******************************************************************************
*
* FUNCTION: AcpiDsCreateBufferField
*
* PARAMETERS: Op - Current parse op (CreateXXField)
* WalkState - Current state
*
* RETURN: Status
*
* DESCRIPTION: Execute the CreateField operators:
* CreateBitFieldOp,
* CreateByteFieldOp,
* CreateWordFieldOp,
* CreateDWordFieldOp,
* CreateQWordFieldOp,
* CreateFieldOp (all of which define a field in a buffer)
*
******************************************************************************/
ACPI_STATUS
AcpiDsCreateBufferField (
ACPI_PARSE_OBJECT *Op,
ACPI_WALK_STATE *WalkState)
{
ACPI_PARSE_OBJECT *Arg;
ACPI_NAMESPACE_NODE *Node;
ACPI_STATUS Status;
ACPI_OPERAND_OBJECT *ObjDesc;
ACPI_OPERAND_OBJECT *SecondDesc = NULL;
UINT32 Flags;
ACPI_FUNCTION_TRACE (DsCreateBufferField);
/*
* Get the NameString argument (name of the new BufferField)
*/
if (Op->Common.AmlOpcode == AML_CREATE_FIELD_OP)
{
/* For CreateField, name is the 4th argument */
Arg = AcpiPsGetArg (Op, 3);
}
else
{
/* For all other CreateXXXField operators, name is the 3rd argument */
Arg = AcpiPsGetArg (Op, 2);
}
if (!Arg)
{
return_ACPI_STATUS (AE_AML_NO_OPERAND);
}
if (WalkState->DeferredNode)
{
Node = WalkState->DeferredNode;
Status = AE_OK;
}
else
{
/* Execute flag should always be set when this function is entered */
if (!(WalkState->ParseFlags & ACPI_PARSE_EXECUTE))
{
return_ACPI_STATUS (AE_AML_INTERNAL);
}
/* Creating new namespace node, should not already exist */
Flags = ACPI_NS_NO_UPSEARCH | ACPI_NS_DONT_OPEN_SCOPE |
ACPI_NS_ERROR_IF_FOUND;
/*
* Mark node temporary if we are executing a normal control
* method. (Don't mark if this is a module-level code method)
*/
if (WalkState->MethodNode &&
!(WalkState->ParseFlags & ACPI_PARSE_MODULE_LEVEL))
{
Flags |= ACPI_NS_TEMPORARY;
}
/* Enter the NameString into the namespace */
Status = AcpiNsLookup (WalkState->ScopeInfo, Arg->Common.Value.String,
ACPI_TYPE_ANY, ACPI_IMODE_LOAD_PASS1,
Flags, WalkState, &Node);
if (ACPI_FAILURE (Status))
{
ACPI_ERROR_NAMESPACE (Arg->Common.Value.String, Status);
return_ACPI_STATUS (Status);
}
}
/*
* We could put the returned object (Node) on the object stack for later,
* but for now, we will put it in the "op" object that the parser uses,
* so we can get it again at the end of this scope.
*/
Op->Common.Node = Node;
/*
* If there is no object attached to the node, this node was just created
* and we need to create the field object. Otherwise, this was a lookup
* of an existing node and we don't want to create the field object again.
*/
ObjDesc = AcpiNsGetAttachedObject (Node);
if (ObjDesc)
{
return_ACPI_STATUS (AE_OK);
}
/*
* The Field definition is not fully parsed at this time.
* (We must save the address of the AML for the buffer and index operands)
*/
/* Create the buffer field object */
ObjDesc = AcpiUtCreateInternalObject (ACPI_TYPE_BUFFER_FIELD);
if (!ObjDesc)
{
Status = AE_NO_MEMORY;
goto Cleanup;
}
/*
* Remember location in AML stream of the field unit opcode and operands --
* since the buffer and index operands must be evaluated.
*/
SecondDesc = ObjDesc->Common.NextObject;
SecondDesc->Extra.AmlStart = Op->Named.Data;
SecondDesc->Extra.AmlLength = Op->Named.Length;
ObjDesc->BufferField.Node = Node;
/* Attach constructed field descriptors to parent node */
Status = AcpiNsAttachObject (Node, ObjDesc, ACPI_TYPE_BUFFER_FIELD);
if (ACPI_FAILURE (Status))
{
goto Cleanup;
}
Cleanup:
/* Remove local reference to the object */
AcpiUtRemoveReference (ObjDesc);
return_ACPI_STATUS (Status);
}
/*******************************************************************************
*
* FUNCTION: AcpiDsGetFieldNames
*
* PARAMETERS: Info - CreateField info structure
* ` WalkState - Current method state
* Arg - First parser arg for the field name list
*
* RETURN: Status
*
* DESCRIPTION: Process all named fields in a field declaration. Names are
* entered into the namespace.
*
******************************************************************************/
static ACPI_STATUS
AcpiDsGetFieldNames (
ACPI_CREATE_FIELD_INFO *Info,
ACPI_WALK_STATE *WalkState,
ACPI_PARSE_OBJECT *Arg)
{
ACPI_STATUS Status;
UINT64 Position;
ACPI_FUNCTION_TRACE_PTR (DsGetFieldNames, Info);
/* First field starts at bit zero */
Info->FieldBitPosition = 0;
/* Process all elements in the field list (of parse nodes) */
while (Arg)
{
/*
* Three types of field elements are handled:
* 1) Offset - specifies a bit offset
* 2) AccessAs - changes the access mode
* 3) Name - Enters a new named field into the namespace
*/
switch (Arg->Common.AmlOpcode)
{
case AML_INT_RESERVEDFIELD_OP:
Position = (UINT64) Info->FieldBitPosition
+ (UINT64) Arg->Common.Value.Size;
if (Position > ACPI_UINT32_MAX)
{
ACPI_ERROR ((AE_INFO,
"Bit offset within field too large (> 0xFFFFFFFF)"));
return_ACPI_STATUS (AE_SUPPORT);
}
Info->FieldBitPosition = (UINT32) Position;
break;
case AML_INT_ACCESSFIELD_OP:
/*
* Get a new AccessType and AccessAttribute -- to be used for all
* field units that follow, until field end or another AccessAs
* keyword.
*
* In FieldFlags, preserve the flag bits other than the
* ACCESS_TYPE bits
*/
Info->FieldFlags = (UINT8)
((Info->FieldFlags & ~(AML_FIELD_ACCESS_TYPE_MASK)) |
((UINT8) ((UINT32) Arg->Common.Value.Integer >> 8)));
Info->Attribute = (UINT8) (Arg->Common.Value.Integer);
break;
case AML_INT_NAMEDFIELD_OP:
/* Lookup the name, it should already exist */
Status = AcpiNsLookup (WalkState->ScopeInfo,
(char *) &Arg->Named.Name, Info->FieldType,
ACPI_IMODE_EXECUTE, ACPI_NS_DONT_OPEN_SCOPE,
WalkState, &Info->FieldNode);
if (ACPI_FAILURE (Status))
{
ACPI_ERROR_NAMESPACE ((char *) &Arg->Named.Name, Status);
return_ACPI_STATUS (Status);
}
else
{
Arg->Common.Node = Info->FieldNode;
Info->FieldBitLength = Arg->Common.Value.Size;
/*
* If there is no object attached to the node, this node was
* just created and we need to create the field object.
* Otherwise, this was a lookup of an existing node and we
* don't want to create the field object again.
*/
if (!AcpiNsGetAttachedObject (Info->FieldNode))
{
Status = AcpiExPrepFieldValue (Info);
if (ACPI_FAILURE (Status))
{
return_ACPI_STATUS (Status);
}
}
}
/* Keep track of bit position for the next field */
Position = (UINT64) Info->FieldBitPosition
+ (UINT64) Arg->Common.Value.Size;
if (Position > ACPI_UINT32_MAX)
{
ACPI_ERROR ((AE_INFO,
"Field [%4.4s] bit offset too large (> 0xFFFFFFFF)",
ACPI_CAST_PTR (char, &Info->FieldNode->Name)));
return_ACPI_STATUS (AE_SUPPORT);
}
Info->FieldBitPosition += Info->FieldBitLength;
break;
default:
ACPI_ERROR ((AE_INFO,
"Invalid opcode in field list: 0x%X", Arg->Common.AmlOpcode));
return_ACPI_STATUS (AE_AML_BAD_OPCODE);
}
Arg = Arg->Common.Next;
}
return_ACPI_STATUS (AE_OK);
}
/*******************************************************************************
*
* FUNCTION: AcpiDsCreateField
*
* PARAMETERS: Op - Op containing the Field definition and args
* RegionNode - Object for the containing Operation Region
* ` WalkState - Current method state
*
* RETURN: Status
*
* DESCRIPTION: Create a new field in the specified operation region
*
******************************************************************************/
ACPI_STATUS
AcpiDsCreateField (
ACPI_PARSE_OBJECT *Op,
ACPI_NAMESPACE_NODE *RegionNode,
ACPI_WALK_STATE *WalkState)
{
ACPI_STATUS Status;
ACPI_PARSE_OBJECT *Arg;
ACPI_CREATE_FIELD_INFO Info;
ACPI_FUNCTION_TRACE_PTR (DsCreateField, Op);
/* First arg is the name of the parent OpRegion (must already exist) */
Arg = Op->Common.Value.Arg;
if (!RegionNode)
{
Status = AcpiNsLookup (WalkState->ScopeInfo, Arg->Common.Value.Name,
ACPI_TYPE_REGION, ACPI_IMODE_EXECUTE,
ACPI_NS_SEARCH_PARENT, WalkState, &RegionNode);
if (ACPI_FAILURE (Status))
{
ACPI_ERROR_NAMESPACE (Arg->Common.Value.Name, Status);
return_ACPI_STATUS (Status);
}
}
/* Second arg is the field flags */
Arg = Arg->Common.Next;
Info.FieldFlags = (UINT8) Arg->Common.Value.Integer;
Info.Attribute = 0;
/* Each remaining arg is a Named Field */
Info.FieldType = ACPI_TYPE_LOCAL_REGION_FIELD;
Info.RegionNode = RegionNode;
Status = AcpiDsGetFieldNames (&Info, WalkState, Arg->Common.Next);
return_ACPI_STATUS (Status);
}
/*******************************************************************************
*
* FUNCTION: AcpiDsInitFieldObjects
*
* PARAMETERS: Op - Op containing the Field definition and args
* ` WalkState - Current method state
*
* RETURN: Status
*
* DESCRIPTION: For each "Field Unit" name in the argument list that is
* part of the field declaration, enter the name into the
* namespace.
*
******************************************************************************/
ACPI_STATUS
AcpiDsInitFieldObjects (
ACPI_PARSE_OBJECT *Op,
ACPI_WALK_STATE *WalkState)
{
ACPI_STATUS Status;
ACPI_PARSE_OBJECT *Arg = NULL;
ACPI_NAMESPACE_NODE *Node;
UINT8 Type = 0;
UINT32 Flags;
ACPI_FUNCTION_TRACE_PTR (DsInitFieldObjects, Op);
/* Execute flag should always be set when this function is entered */
if (!(WalkState->ParseFlags & ACPI_PARSE_EXECUTE))
{
if (WalkState->ParseFlags & ACPI_PARSE_DEFERRED_OP)
{
/* BankField Op is deferred, just return OK */
return_ACPI_STATUS (AE_OK);
}
return_ACPI_STATUS (AE_AML_INTERNAL);
}
/*
* Get the FieldList argument for this opcode. This is the start of the
* list of field elements.
*/
switch (WalkState->Opcode)
{
case AML_FIELD_OP:
Arg = AcpiPsGetArg (Op, 2);
Type = ACPI_TYPE_LOCAL_REGION_FIELD;
break;
case AML_BANK_FIELD_OP:
Arg = AcpiPsGetArg (Op, 4);
Type = ACPI_TYPE_LOCAL_BANK_FIELD;
break;
case AML_INDEX_FIELD_OP:
Arg = AcpiPsGetArg (Op, 3);
Type = ACPI_TYPE_LOCAL_INDEX_FIELD;
break;
default:
return_ACPI_STATUS (AE_BAD_PARAMETER);
}
/* Creating new namespace node(s), should not already exist */
Flags = ACPI_NS_NO_UPSEARCH | ACPI_NS_DONT_OPEN_SCOPE |
ACPI_NS_ERROR_IF_FOUND;
/*
* Mark node(s) temporary if we are executing a normal control
* method. (Don't mark if this is a module-level code method)
*/
if (WalkState->MethodNode &&
!(WalkState->ParseFlags & ACPI_PARSE_MODULE_LEVEL))
{
Flags |= ACPI_NS_TEMPORARY;
}
/*
* Walk the list of entries in the FieldList
* Note: FieldList can be of zero length. In this case, Arg will be NULL.
*/
while (Arg)
{
/*
* Ignore OFFSET and ACCESSAS terms here; we are only interested in the
* field names in order to enter them into the namespace.
*/
if (Arg->Common.AmlOpcode == AML_INT_NAMEDFIELD_OP)
{
Status = AcpiNsLookup (WalkState->ScopeInfo,
(char *) &Arg->Named.Name, Type, ACPI_IMODE_LOAD_PASS1,
Flags, WalkState, &Node);
if (ACPI_FAILURE (Status))
{
ACPI_ERROR_NAMESPACE ((char *) &Arg->Named.Name, Status);
if (Status != AE_ALREADY_EXISTS)
{
return_ACPI_STATUS (Status);
}
/* Name already exists, just ignore this error */
Status = AE_OK;
}
Arg->Common.Node = Node;
}
/* Get the next field element in the list */
Arg = Arg->Common.Next;
}
return_ACPI_STATUS (AE_OK);
}
/*******************************************************************************
*
* FUNCTION: AcpiDsCreateBankField
*
* PARAMETERS: Op - Op containing the Field definition and args
* RegionNode - Object for the containing Operation Region
* WalkState - Current method state
*
* RETURN: Status
*
* DESCRIPTION: Create a new bank field in the specified operation region
*
******************************************************************************/
ACPI_STATUS
AcpiDsCreateBankField (
ACPI_PARSE_OBJECT *Op,
ACPI_NAMESPACE_NODE *RegionNode,
ACPI_WALK_STATE *WalkState)
{
ACPI_STATUS Status;
ACPI_PARSE_OBJECT *Arg;
ACPI_CREATE_FIELD_INFO Info;
ACPI_FUNCTION_TRACE_PTR (DsCreateBankField, Op);
/* First arg is the name of the parent OpRegion (must already exist) */
Arg = Op->Common.Value.Arg;
if (!RegionNode)
{
Status = AcpiNsLookup (WalkState->ScopeInfo, Arg->Common.Value.Name,
ACPI_TYPE_REGION, ACPI_IMODE_EXECUTE,
ACPI_NS_SEARCH_PARENT, WalkState, &RegionNode);
if (ACPI_FAILURE (Status))
{
ACPI_ERROR_NAMESPACE (Arg->Common.Value.Name, Status);
return_ACPI_STATUS (Status);
}
}
/* Second arg is the Bank Register (Field) (must already exist) */
Arg = Arg->Common.Next;
Status = AcpiNsLookup (WalkState->ScopeInfo, Arg->Common.Value.String,
ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,
ACPI_NS_SEARCH_PARENT, WalkState, &Info.RegisterNode);
if (ACPI_FAILURE (Status))
{
ACPI_ERROR_NAMESPACE (Arg->Common.Value.String, Status);
return_ACPI_STATUS (Status);
}
/*
* Third arg is the BankValue
* This arg is a TermArg, not a constant
* It will be evaluated later, by AcpiDsEvalBankFieldOperands
*/
Arg = Arg->Common.Next;
/* Fourth arg is the field flags */
Arg = Arg->Common.Next;
Info.FieldFlags = (UINT8) Arg->Common.Value.Integer;
/* Each remaining arg is a Named Field */
Info.FieldType = ACPI_TYPE_LOCAL_BANK_FIELD;
Info.RegionNode = RegionNode;
/*
* Use Info.DataRegisterNode to store BankField Op
* It's safe because DataRegisterNode will never be used when create bank field
* We store AmlStart and AmlLength in the BankField Op for late evaluation
* Used in AcpiExPrepFieldValue(Info)
*
* TBD: Or, should we add a field in ACPI_CREATE_FIELD_INFO, like "void *ParentOp"?
*/
Info.DataRegisterNode = (ACPI_NAMESPACE_NODE*) Op;
Status = AcpiDsGetFieldNames (&Info, WalkState, Arg->Common.Next);
return_ACPI_STATUS (Status);
}
/*******************************************************************************
*
* FUNCTION: AcpiDsCreateIndexField
*
* PARAMETERS: Op - Op containing the Field definition and args
* RegionNode - Object for the containing Operation Region
* ` WalkState - Current method state
*
* RETURN: Status
*
* DESCRIPTION: Create a new index field in the specified operation region
*
******************************************************************************/
ACPI_STATUS
AcpiDsCreateIndexField (
ACPI_PARSE_OBJECT *Op,
ACPI_NAMESPACE_NODE *RegionNode,
ACPI_WALK_STATE *WalkState)
{
ACPI_STATUS Status;
ACPI_PARSE_OBJECT *Arg;
ACPI_CREATE_FIELD_INFO Info;
ACPI_FUNCTION_TRACE_PTR (DsCreateIndexField, Op);
/* First arg is the name of the Index register (must already exist) */
Arg = Op->Common.Value.Arg;
Status = AcpiNsLookup (WalkState->ScopeInfo, Arg->Common.Value.String,
ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,
ACPI_NS_SEARCH_PARENT, WalkState, &Info.RegisterNode);
if (ACPI_FAILURE (Status))
{
ACPI_ERROR_NAMESPACE (Arg->Common.Value.String, Status);
return_ACPI_STATUS (Status);
}
/* Second arg is the data register (must already exist) */
Arg = Arg->Common.Next;
Status = AcpiNsLookup (WalkState->ScopeInfo, Arg->Common.Value.String,
ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,
ACPI_NS_SEARCH_PARENT, WalkState, &Info.DataRegisterNode);
if (ACPI_FAILURE (Status))
{
ACPI_ERROR_NAMESPACE (Arg->Common.Value.String, Status);
return_ACPI_STATUS (Status);
}
/* Next arg is the field flags */
Arg = Arg->Common.Next;
Info.FieldFlags = (UINT8) Arg->Common.Value.Integer;
/* Each remaining arg is a Named Field */
Info.FieldType = ACPI_TYPE_LOCAL_INDEX_FIELD;
Info.RegionNode = RegionNode;
Status = AcpiDsGetFieldNames (&Info, WalkState, Arg->Common.Next);
return_ACPI_STATUS (Status);
}