FreeBSD/Linux Kernel Cross Reference
sys/contrib/dev/acpica/compiler/aslanalyze.c

     /******************************************************************************
      *
      * Module Name: aslanalyze.c - Support functions for parse tree walks
      *
      *****************************************************************************/
     
     /******************************************************************************
      *
      * 1. Copyright Notice
     *
     * Some or all of this work - Copyright (c) 1999 - 2022, 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.
    *
    *****************************************************************************
    *
    * Alternatively, you may choose to be licensed under the terms of the
    * following license:
    *
    * Redistribution and use in source and binary forms, with or without
    * modification, are permitted provided that the following conditions
    * are met:
    * 1. Redistributions of source code must retain the above copyright
    *    notice, this list of conditions, and the following disclaimer,
    *    without modification.
    * 2. Redistributions in binary form must reproduce at minimum a disclaimer
    *    substantially similar to the "NO WARRANTY" disclaimer below
    *    ("Disclaimer") and any redistribution must be conditioned upon
    *    including a substantially similar Disclaimer requirement for further
    *    binary redistribution.
    * 3. Neither the names of the above-listed copyright holders nor the names
    *    of any contributors may be used to endorse or promote products derived
    *    from this software without specific prior written permission.
    *
    * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
    * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
    * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
    * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
    * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
    * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
    * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
    * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
    * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
    * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
    * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
    *
    * Alternatively, you may choose to be licensed under the terms of the
    * GNU General Public License ("GPL") version 2 as published by the Free
    * Software Foundation.
    *
    *****************************************************************************/
   
   #include <contrib/dev/acpica/compiler/aslcompiler.h>
   #include "aslcompiler.y.h"
   #include <contrib/dev/acpica/include/acnamesp.h>
   #include <string.h>
   
   
   #define _COMPONENT          ACPI_COMPILER
           ACPI_MODULE_NAME    ("aslanalyze")
   
   
   /* Local Prototypes */
   
   static ACPI_STATUS
   ApDeviceSubtreeWalk (
       ACPI_PARSE_OBJECT       *Op,
       UINT32                  Level,
       void                    *Context);
   
   
   /*******************************************************************************
    *
    * FUNCTION:    AnIsInternalMethod
    *
    * PARAMETERS:  Op                  - Current op
    *
    * RETURN:      Boolean
    *
    * DESCRIPTION: Check for an internal control method.
    *
    ******************************************************************************/
   
   BOOLEAN
   AnIsInternalMethod (
       ACPI_PARSE_OBJECT       *Op)
   {
   
       if ((!strcmp (Op->Asl.ExternalName, "\\_OSI")) ||
           (!strcmp (Op->Asl.ExternalName, "_OSI")))
       {
           return (TRUE);
       }
   
       return (FALSE);
   }
   
   
   /*******************************************************************************
    *
    * FUNCTION:    AnGetInternalMethodReturnType
    *
    * PARAMETERS:  Op                  - Current op
    *
    * RETURN:      Btype
    *
    * DESCRIPTION: Get the return type of an internal method
    *
    ******************************************************************************/
   
   UINT32
   AnGetInternalMethodReturnType (
       ACPI_PARSE_OBJECT       *Op)
   {
   
       if ((!strcmp (Op->Asl.ExternalName, "\\_OSI")) ||
           (!strcmp (Op->Asl.ExternalName, "_OSI")))
       {
           return (ACPI_BTYPE_STRING);
       }
   
       return (0);
   }
   
   
   /*******************************************************************************
    *
    * FUNCTION:    AnCheckId
    *
    * PARAMETERS:  Op                  - Current parse op
    *              Type                - HID or CID
    *
    * RETURN:      None
    *
    * DESCRIPTION: Perform various checks on _HID and _CID strings. Only limited
    *              checks can be performed on _CID strings.
    *
    ******************************************************************************/
   
   void
   AnCheckId (
       ACPI_PARSE_OBJECT       *Op,
       ACPI_NAME               Type)
   {
       UINT32                  i;
       ACPI_SIZE               Length;
   
   
       /* Only care about string versions of _HID/_CID (integers are legal) */
   
       if (Op->Asl.ParseOpcode != PARSEOP_STRING_LITERAL)
       {
           return;
       }
   
       /* For both _HID and _CID, the string must be non-null */
   
       Length = strlen (Op->Asl.Value.String);
       if (!Length)
       {
           AslError (ASL_ERROR, ASL_MSG_NULL_STRING, Op, NULL);
           return;
       }
   
       /*
        * One of the things we want to catch here is the use of a leading
        * asterisk in the string -- an odd construct that certain platform
        * manufacturers are fond of. Technically, a leading asterisk is OK
        * for _CID, but a valid use of this has not been seen.
        */
       if (*Op->Asl.Value.String == '*')
       {
           AslError (ASL_ERROR, ASL_MSG_LEADING_ASTERISK,
               Op, Op->Asl.Value.String);
           return;
       }
   
       /* _CID strings are bus-specific, no more checks can be performed */
   
       if (Type == ASL_TYPE_CID)
       {
           return;
       }
   
       /* For _HID, all characters must be alphanumeric */
   
       for (i = 0; Op->Asl.Value.String[i]; i++)
       {
           if (!isalnum ((int) Op->Asl.Value.String[i]))
           {
               AslError (ASL_ERROR, ASL_MSG_ALPHANUMERIC_STRING,
                   Op, Op->Asl.Value.String);
               return;
           }
       }
   
       /*
        * _HID String must be one of these forms:
        *
        * "AAA####"    A is an uppercase letter and # is a hex digit
        * "ACPI####"   # is a hex digit
        * "NNNN####"   N is an uppercase letter or decimal digit (0-9)
        *              # is a hex digit (ACPI 5.0)
        */
       if ((Length < 7) || (Length > 8))
       {
           AslError (ASL_ERROR, ASL_MSG_HID_LENGTH,
               Op, Op->Asl.Value.String);
           return;
       }
   
       /* _HID Length is valid (7 or 8), now check prefix (first 3 or 4 chars) */
   
       if (Length == 7)
       {
           /* AAA####: Ensure the alphabetic prefix is all uppercase */
   
           for (i = 0; i < 3; i++)
           {
               if (!isupper ((int) Op->Asl.Value.String[i]))
               {
                   AslError (ASL_ERROR, ASL_MSG_UPPER_CASE,
                       Op, &Op->Asl.Value.String[i]);
                   return;
               }
           }
       }
       else /* Length == 8 */
       {
           /*
            * ACPI#### or NNNN####:
            * Ensure the prefix contains only uppercase alpha or decimal digits
            */
           for (i = 0; i < 4; i++)
           {
               if (!isupper ((int) Op->Asl.Value.String[i]) &&
                   !isdigit ((int) Op->Asl.Value.String[i]))
               {
                   AslError (ASL_ERROR, ASL_MSG_HID_PREFIX,
                       Op, &Op->Asl.Value.String[i]);
                   return;
               }
           }
       }
   
       /* Remaining characters (suffix) must be hex digits */
   
       for (; i < Length; i++)
       {
           if (!isxdigit ((int) Op->Asl.Value.String[i]))
           {
               AslError (ASL_ERROR, ASL_MSG_HID_SUFFIX,
                   Op, &Op->Asl.Value.String[i]);
               break;
           }
       }
   }
   
   
   /*******************************************************************************
    *
    * FUNCTION:    AnLastStatementIsReturn
    *
    * PARAMETERS:  Op                  - A method parse node
    *
    * RETURN:      TRUE if last statement is an ASL RETURN. False otherwise
    *
    * DESCRIPTION: Walk down the list of top level statements within a method
    *              to find the last one. Check if that last statement is in
    *              fact a RETURN statement.
    *
    ******************************************************************************/
   
   BOOLEAN
   AnLastStatementIsReturn (
       ACPI_PARSE_OBJECT       *Op)
   {
       ACPI_PARSE_OBJECT       *Next;
   
   
       /* Check if last statement is a return */
   
       Next = ASL_GET_CHILD_NODE (Op);
       while (Next)
       {
           if ((!Next->Asl.Next) &&
               (Next->Asl.ParseOpcode == PARSEOP_RETURN))
           {
               return (TRUE);
           }
   
           Next = ASL_GET_PEER_NODE (Next);
       }
   
       return (FALSE);
   }
   
   
   /*******************************************************************************
    *
    * FUNCTION:    AnCheckMethodReturnValue
    *
    * PARAMETERS:  Op                  - Parent
    *              OpInfo              - Parent info
    *              ArgOp               - Method invocation op
    *              RequiredBtypes      - What caller requires
    *              ThisNodeBtype       - What this node returns (if anything)
    *
    * RETURN:      None
    *
    * DESCRIPTION: Check a method invocation for 1) A return value and if it does
    *              in fact return a value, 2) check the type of the return value.
    *
    ******************************************************************************/
   
   void
   AnCheckMethodReturnValue (
       ACPI_PARSE_OBJECT       *Op,
       const ACPI_OPCODE_INFO  *OpInfo,
       ACPI_PARSE_OBJECT       *ArgOp,
       UINT32                  RequiredBtypes,
       UINT32                  ThisNodeBtype)
   {
       ACPI_PARSE_OBJECT       *OwningOp;
       ACPI_NAMESPACE_NODE     *Node;
       char                    *ExternalPath;
   
   
       Node = ArgOp->Asl.Node;
   
       if (!Node)
       {
           /* No error message, this can happen and is OK */
   
           return;
       }
   
       /* Examine the parent op of this method */
   
       OwningOp = Node->Op;
       ExternalPath = AcpiNsGetNormalizedPathname (Node, TRUE);
   
       if (OwningOp->Asl.CompileFlags & OP_METHOD_NO_RETVAL)
       {
           /* Method NEVER returns a value */
   
           AslError (ASL_ERROR, ASL_MSG_NO_RETVAL, Op, ExternalPath);
       }
       else if (OwningOp->Asl.CompileFlags & OP_METHOD_SOME_NO_RETVAL)
       {
           /* Method SOMETIMES returns a value, SOMETIMES not */
   
           AslError (ASL_WARNING, ASL_MSG_SOME_NO_RETVAL, Op, ExternalPath);
       }
       else if (!(ThisNodeBtype & RequiredBtypes))
       {
           /* Method returns a value, but the type is wrong */
   
           AnFormatBtype (AslGbl_StringBuffer, ThisNodeBtype);
           AnFormatBtype (AslGbl_StringBuffer2, RequiredBtypes);
   
           /*
            * The case where the method does not return any value at all
            * was already handled in the namespace cross reference
            * -- Only issue an error if the method in fact returns a value,
            * but it is of the wrong type
            */
           if (ThisNodeBtype != 0)
           {
               sprintf (AslGbl_MsgBuffer,
                   "Method returns [%s], %s operator requires [%s]",
                   AslGbl_StringBuffer, OpInfo->Name, AslGbl_StringBuffer2);
   
               AslError (ASL_WARNING, ASL_MSG_INVALID_TYPE, ArgOp, AslGbl_MsgBuffer);
           }
       }
   
       if (ExternalPath)
       {
           ACPI_FREE (ExternalPath);
       }
   }
   
   
   /*******************************************************************************
    *
    * FUNCTION:    AnIsResultUsed
    *
    * PARAMETERS:  Op                  - Parent op for the operator
    *
    * RETURN:      TRUE if result from this operation is actually consumed
    *
    * DESCRIPTION: Determine if the function result value from an operator is
    *              used.
    *
    ******************************************************************************/
   
   BOOLEAN
   AnIsResultUsed (
       ACPI_PARSE_OBJECT       *Op)
   {
       ACPI_PARSE_OBJECT       *Parent;
   
   
       switch (Op->Asl.ParseOpcode)
       {
       case PARSEOP_INCREMENT:
       case PARSEOP_DECREMENT:
   
           /* These are standalone operators, no return value */
   
           return (TRUE);
   
       default:
   
           break;
       }
   
       /* Examine parent to determine if the return value is used */
   
       Parent = Op->Asl.Parent;
       switch (Parent->Asl.ParseOpcode)
       {
       /* If/While - check if the operator is the predicate */
   
       case PARSEOP_IF:
       case PARSEOP_WHILE:
   
           /* First child is the predicate */
   
           if (Parent->Asl.Child == Op)
           {
               return (TRUE);
           }
   
           return (FALSE);
   
       /* Not used if one of these is the parent */
   
       case PARSEOP_METHOD:
       case PARSEOP_DEFINITION_BLOCK:
       case PARSEOP_ELSE:
   
           return (FALSE);
   
       default:
   
           /* Any other type of parent means that the result is used */
   
           return (TRUE);
       }
   }
   
   
   /*******************************************************************************
    *
    * FUNCTION:    ApCheckForGpeNameConflict
    *
    * PARAMETERS:  Op                  - Current parse op
    *
    * RETURN:      None
    *
    * DESCRIPTION: Check for a conflict between GPE names within this scope.
    *              Conflict means two GPE names with the same GPE number, but
    *              different types -- such as _L1C and _E1C.
    *
    ******************************************************************************/
   
   void
   ApCheckForGpeNameConflict (
       ACPI_PARSE_OBJECT       *Op)
   {
       ACPI_PARSE_OBJECT       *NextOp;
       UINT32                  GpeNumber;
       char                    Name[ACPI_NAMESEG_SIZE + 1];
       char                    Target[ACPI_NAMESEG_SIZE];
   
   
       /* Need a null-terminated string version of NameSeg */
   
       ACPI_MOVE_32_TO_32 (Name, Op->Asl.NameSeg);
       Name[ACPI_NAMESEG_SIZE] = 0;
   
       /*
        * For a GPE method:
        * 1st char must be underscore
        * 2nd char must be L or E
        * 3rd/4th chars must be a hex number
        */
       if ((Name[0] != '_') ||
          ((Name[1] != 'L') && (Name[1] != 'E')))
       {
           return;
       }
   
       /* Verify 3rd/4th chars are a valid hex value */
   
       GpeNumber = strtoul (&Name[2], NULL, 16);
       if (GpeNumber == ACPI_UINT32_MAX)
       {
           return;
       }
   
       /*
        * We are now sure we have an _Lxx or _Exx.
        * Create the target name that would cause collision (Flip E/L)
        */
       ACPI_MOVE_32_TO_32 (Target, Name);
   
       /* Inject opposite letter ("L" versus "E") */
   
       if (Name[1] == 'L')
       {
           Target[1] = 'E';
       }
       else /* Name[1] == 'E' */
       {
           Target[1] = 'L';
       }
   
       /* Search all peers (objects within this scope) for target match */
   
       NextOp = Op->Asl.Next;
       while (NextOp)
       {
           /*
            * We mostly care about methods, but check Name() constructs also,
            * even though they will get another error for not being a method.
            * All GPE names must be defined as control methods.
            */
           if ((NextOp->Asl.ParseOpcode == PARSEOP_METHOD) ||
               (NextOp->Asl.ParseOpcode == PARSEOP_NAME))
           {
               if (ACPI_COMPARE_NAMESEG (Target, NextOp->Asl.NameSeg))
               {
                   /* Found both _Exy and _Lxy in the same scope, error */
   
                   AslError (ASL_ERROR, ASL_MSG_GPE_NAME_CONFLICT, NextOp,
                       Name);
                   return;
               }
           }
   
           NextOp = NextOp->Asl.Next;
       }
   
       /* OK, no conflict found */
   
       return;
   }
   
   
   /*******************************************************************************
    *
    * FUNCTION:    ApCheckRegMethod
    *
    * PARAMETERS:  Op                  - Current parse op
    *
    * RETURN:      None
    *
    * DESCRIPTION: Ensure that a _REG method has a corresponding Operation
    *              Region declaration within the same scope. Note: _REG is defined
    *              to have two arguments and must therefore be defined as a
    *              control method.
    *
    ******************************************************************************/
   
   void
   ApCheckRegMethod (
       ACPI_PARSE_OBJECT       *Op)
   {
       ACPI_PARSE_OBJECT       *Next;
       ACPI_PARSE_OBJECT       *Parent;
   
   
       /* We are only interested in _REG methods */
   
       if (!ACPI_COMPARE_NAMESEG (METHOD_NAME__REG, &Op->Asl.NameSeg))
       {
           return;
       }
   
       /* Get the start of the current scope */
   
       Parent = Op->Asl.Parent;
       Next = Parent->Asl.Child;
   
       /* Search entire scope for an operation region declaration */
   
       while (Next)
       {
           if (Next->Asl.ParseOpcode == PARSEOP_OPERATIONREGION)
           {
               return; /* Found region, OK */
           }
   
           Next = Next->Asl.Next;
       }
   
       /* No region found, issue warning */
   
       AslError (ASL_WARNING, ASL_MSG_NO_REGION, Op, NULL);
   }
   
   
   /*******************************************************************************
    *
    * FUNCTION:    ApFindNameInDeviceTree
    *
    * PARAMETERS:  Name                - Name to search for
    *              Op                  - Current parse op
    *
    * RETURN:      TRUE if name found in the same scope as Op.
    *
    * DESCRIPTION: Determine if a name appears in the same scope as Op, as either
    *              a Method() or a Name(). "Same scope" can mean under an If or
    *              Else statement.
    *
    * NOTE: Detects _HID/_ADR in this type of construct (legal in ACPI 6.1+)
    *
    * Scope (\_SB.PCI0)
    * {
    *     Device (I2C0)
    *     {
    *         If (SMD0 != 4) {
    *             Name (_HID, "INT3442")
    *         } Else {
    *             Name (_ADR, 0x400)
    *         }
    *     }
    * }
    ******************************************************************************/
   
   BOOLEAN
   ApFindNameInDeviceTree (
       char                    *Name,
       ACPI_PARSE_OBJECT       *Op)
   {
       ACPI_STATUS             Status;
   
   
       Status = TrWalkParseTree (Op, ASL_WALK_VISIT_DOWNWARD,
           ApDeviceSubtreeWalk, NULL, Name);
   
       if (Status == AE_CTRL_TRUE)
       {
           return (TRUE);  /* Found a match */
       }
   
       return (FALSE);
   }
   
   
   /* Callback function for interface above */
   
   static ACPI_STATUS
   ApDeviceSubtreeWalk (
       ACPI_PARSE_OBJECT       *Op,
       UINT32                  Level,
       void                    *Context)
   {
       char                    *Name = ACPI_CAST_PTR (char, Context);
   
   
       switch (Op->Asl.ParseOpcode)
       {
       case PARSEOP_DEVICE:
   
           /* Level 0 is the starting device, ignore it */
   
           if (Level > 0)
           {
               /* Ignore sub-devices */
   
               return (AE_CTRL_DEPTH);
           }
           break;
   
       case PARSEOP_NAME:
       case PARSEOP_METHOD:
   
           /* These are what we are looking for */
   
           if (ACPI_COMPARE_NAMESEG (Name, Op->Asl.NameSeg))
           {
               return (AE_CTRL_TRUE);
           }
           return (AE_CTRL_DEPTH);
   
       case PARSEOP_SCOPE:
       case PARSEOP_FIELD:
       case PARSEOP_OPERATIONREGION:
   
           /*
            * We want to ignore these, because either they can be large
            * subtrees or open a scope to somewhere else.
            */
           return (AE_CTRL_DEPTH);
   
       default:
           break;
       }
   
       return (AE_OK);
   }
   
   
   /*******************************************************************************
    *
    * FUNCTION:    ApFindNameInScope
    *
    * PARAMETERS:  Name                - Name to search for
    *              Op                  - Current parse op
    *
    * RETURN:      TRUE if name found in the same scope as Op.
    *
    * DESCRIPTION: Determine if a name appears in the same scope as Op, as either
    *              a Method() or a Name().
    *
    ******************************************************************************/
   
   BOOLEAN
   ApFindNameInScope (
       char                    *Name,
       ACPI_PARSE_OBJECT       *Op)
   {
       ACPI_PARSE_OBJECT       *Next;
       ACPI_PARSE_OBJECT       *Parent;
   
   
       /* Get the start of the current scope */
   
       Parent = Op->Asl.Parent;
       Next = Parent->Asl.Child;
   
       /* Search entire scope for a match to the name */
   
       while (Next)
       {
           if ((Next->Asl.ParseOpcode == PARSEOP_METHOD) ||
               (Next->Asl.ParseOpcode == PARSEOP_NAME))
           {
               if (ACPI_COMPARE_NAMESEG (Name, Next->Asl.NameSeg))
               {
                   return (TRUE);
               }
           }
   
           Next = Next->Asl.Next;
       }
   
       return (FALSE);
   }

Cache object: 8c41ae60ebd684ac26e0951da0460f0d