FreeBSD/Linux Kernel Cross Reference
sys/contrib/dev/acpica/components/namespace/nsxfeval.c

     /*******************************************************************************
      *
      * Module Name: nsxfeval - Public interfaces to the ACPI subsystem
      *                         ACPI Object evaluation interfaces
      *
      ******************************************************************************/
     
     /******************************************************************************
      *
     * 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.
    *
    *****************************************************************************/
   
   #define EXPORT_ACPI_INTERFACES
   
   #include <contrib/dev/acpica/include/acpi.h>
   #include <contrib/dev/acpica/include/accommon.h>
   #include <contrib/dev/acpica/include/acnamesp.h>
   #include <contrib/dev/acpica/include/acinterp.h>
   
   
   #define _COMPONENT          ACPI_NAMESPACE
           ACPI_MODULE_NAME    ("nsxfeval")
   
   /* Local prototypes */
   
   static void
   AcpiNsResolveReferences (
       ACPI_EVALUATE_INFO      *Info);
   
   
   /*******************************************************************************
    *
    * FUNCTION:    AcpiEvaluateObjectTyped
    *
    * PARAMETERS:  Handle              - Object handle (optional)
    *              Pathname            - Object pathname (optional)
    *              ExternalParams      - List of parameters to pass to a method,
    *                                    terminated by NULL. May be NULL
    *                                    if no parameters are being passed.
    *              ReturnBuffer        - Where to put the object return value (if
    *                                    any). Required.
    *              ReturnType          - Expected type of return object
    *
    * RETURN:      Status
    *
    * DESCRIPTION: Find and evaluate the given object, passing the given
    *              parameters if necessary. One of "Handle" or "Pathname" must
    *              be valid (non-null)
    *
    ******************************************************************************/
   
   ACPI_STATUS
   AcpiEvaluateObjectTyped (
       ACPI_HANDLE             Handle,
       ACPI_STRING             Pathname,
       ACPI_OBJECT_LIST        *ExternalParams,
       ACPI_BUFFER             *ReturnBuffer,
       ACPI_OBJECT_TYPE        ReturnType)
   {
       ACPI_STATUS             Status;
       BOOLEAN                 FreeBufferOnError = FALSE;
       ACPI_HANDLE             TargetHandle;
       char                    *FullPathname;
   
   
       ACPI_FUNCTION_TRACE (AcpiEvaluateObjectTyped);
   
   
       /* Return buffer must be valid */
   
       if (!ReturnBuffer)
       {
           return_ACPI_STATUS (AE_BAD_PARAMETER);
       }
   
       if (ReturnBuffer->Length == ACPI_ALLOCATE_BUFFER)
       {
           FreeBufferOnError = TRUE;
       }
   
       /* Get a handle here, in order to build an error message if needed */
   
       TargetHandle = Handle;
       if (Pathname)
       {
           Status = AcpiGetHandle (Handle, Pathname, &TargetHandle);
           if (ACPI_FAILURE (Status))
           {
               return_ACPI_STATUS (Status);
           }
       }
   
       FullPathname = AcpiNsGetExternalPathname (TargetHandle);
       if (!FullPathname)
       {
           return_ACPI_STATUS (AE_NO_MEMORY);
       }
   
       /* Evaluate the object */
   
       Status = AcpiEvaluateObject (TargetHandle, NULL, ExternalParams,
           ReturnBuffer);
       if (ACPI_FAILURE (Status))
       {
           goto Exit;
       }
   
       /* Type ANY means "don't care about return value type" */
   
       if (ReturnType == ACPI_TYPE_ANY)
       {
           goto Exit;
       }
   
       if (ReturnBuffer->Length == 0)
       {
           /* Error because caller specifically asked for a return value */
   
           ACPI_ERROR ((AE_INFO, "%s did not return any object",
               FullPathname));
           Status = AE_NULL_OBJECT;
           goto Exit;
       }
   
       /* Examine the object type returned from EvaluateObject */
   
       if (((ACPI_OBJECT *) ReturnBuffer->Pointer)->Type == ReturnType)
       {
           goto Exit;
       }
   
       /* Return object type does not match requested type */
   
       ACPI_ERROR ((AE_INFO,
           "Incorrect return type from %s - received [%s], requested [%s]",
           FullPathname,
           AcpiUtGetTypeName (((ACPI_OBJECT *) ReturnBuffer->Pointer)->Type),
           AcpiUtGetTypeName (ReturnType)));
   
       if (FreeBufferOnError)
       {
           /*
            * Free a buffer created via ACPI_ALLOCATE_BUFFER.
            * Note: We use AcpiOsFree here because AcpiOsAllocate was used
            * to allocate the buffer. This purposefully bypasses the
            * (optionally enabled) allocation tracking mechanism since we
            * only want to track internal allocations.
            */
           AcpiOsFree (ReturnBuffer->Pointer);
           ReturnBuffer->Pointer = NULL;
       }
   
       ReturnBuffer->Length = 0;
       Status = AE_TYPE;
   
   Exit:
       ACPI_FREE (FullPathname);
       return_ACPI_STATUS (Status);
   }
   
   ACPI_EXPORT_SYMBOL (AcpiEvaluateObjectTyped)
   
   
   /*******************************************************************************
    *
    * FUNCTION:    AcpiEvaluateObject
    *
    * PARAMETERS:  Handle              - Object handle (optional)
    *              Pathname            - Object pathname (optional)
    *              ExternalParams      - List of parameters to pass to method,
    *                                    terminated by NULL. May be NULL
    *                                    if no parameters are being passed.
    *              ReturnBuffer        - Where to put method's return value (if
    *                                    any). If NULL, no value is returned.
    *
    * RETURN:      Status
    *
    * DESCRIPTION: Find and evaluate the given object, passing the given
    *              parameters if necessary. One of "Handle" or "Pathname" must
    *              be valid (non-null)
    *
    ******************************************************************************/
   
   ACPI_STATUS
   AcpiEvaluateObject (
       ACPI_HANDLE             Handle,
       ACPI_STRING             Pathname,
       ACPI_OBJECT_LIST        *ExternalParams,
       ACPI_BUFFER             *ReturnBuffer)
   {
       ACPI_STATUS             Status;
       ACPI_EVALUATE_INFO      *Info;
       ACPI_SIZE               BufferSpaceNeeded;
       UINT32                  i;
   
   
       ACPI_FUNCTION_TRACE (AcpiEvaluateObject);
   
   
       /* Allocate and initialize the evaluation information block */
   
       Info = ACPI_ALLOCATE_ZEROED (sizeof (ACPI_EVALUATE_INFO));
       if (!Info)
       {
           return_ACPI_STATUS (AE_NO_MEMORY);
       }
   
       /* Convert and validate the device handle */
   
       Info->PrefixNode = AcpiNsValidateHandle (Handle);
       if (!Info->PrefixNode)
       {
           Status = AE_BAD_PARAMETER;
           goto Cleanup;
       }
   
       /*
        * Get the actual namespace node for the target object.
        * Handles these cases:
        *
        * 1) Null node, valid pathname from root (absolute path)
        * 2) Node and valid pathname (path relative to Node)
        * 3) Node, Null pathname
        */
       if ((Pathname) &&
           (ACPI_IS_ROOT_PREFIX (Pathname[0])))
       {
           /* The path is fully qualified, just evaluate by name */
   
           Info->PrefixNode = NULL;
       }
       else if (!Handle)
       {
           /*
            * A handle is optional iff a fully qualified pathname is specified.
            * Since we've already handled fully qualified names above, this is
            * an error.
            */
           if (!Pathname)
           {
               ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
                   "Both Handle and Pathname are NULL"));
           }
           else
           {
               ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
                   "Null Handle with relative pathname [%s]", Pathname));
           }
   
           Status = AE_BAD_PARAMETER;
           goto Cleanup;
       }
   
       Info->RelativePathname = Pathname;
   
       /*
        * Convert all external objects passed as arguments to the
        * internal version(s).
        */
       if (ExternalParams && ExternalParams->Count)
       {
           Info->ParamCount = (UINT16) ExternalParams->Count;
   
           /* Warn on impossible argument count */
   
           if (Info->ParamCount > ACPI_METHOD_NUM_ARGS)
           {
               ACPI_WARN_PREDEFINED ((AE_INFO, Pathname, ACPI_WARN_ALWAYS,
                   "Excess arguments (%u) - using only %u",
                   Info->ParamCount, ACPI_METHOD_NUM_ARGS));
   
               Info->ParamCount = ACPI_METHOD_NUM_ARGS;
           }
   
           /*
            * Allocate a new parameter block for the internal objects
            * Add 1 to count to allow for null terminated internal list
            */
           Info->Parameters = ACPI_ALLOCATE_ZEROED (
               ((ACPI_SIZE) Info->ParamCount + 1) * sizeof (void *));
           if (!Info->Parameters)
           {
               Status = AE_NO_MEMORY;
               goto Cleanup;
           }
   
           /* Convert each external object in the list to an internal object */
   
           for (i = 0; i < Info->ParamCount; i++)
           {
               Status = AcpiUtCopyEobjectToIobject (
                   &ExternalParams->Pointer[i], &Info->Parameters[i]);
               if (ACPI_FAILURE (Status))
               {
                   goto Cleanup;
               }
           }
   
           Info->Parameters[Info->ParamCount] = NULL;
       }
   
   
   #ifdef _FUTURE_FEATURE
   
       /*
        * Begin incoming argument count analysis. Check for too few args
        * and too many args.
        */
       switch (AcpiNsGetType (Info->Node))
       {
       case ACPI_TYPE_METHOD:
   
           /* Check incoming argument count against the method definition */
   
           if (Info->ObjDesc->Method.ParamCount > Info->ParamCount)
           {
               ACPI_ERROR ((AE_INFO,
                   "Insufficient arguments (%u) - %u are required",
                   Info->ParamCount,
                   Info->ObjDesc->Method.ParamCount));
   
               Status = AE_MISSING_ARGUMENTS;
               goto Cleanup;
           }
   
           else if (Info->ObjDesc->Method.ParamCount < Info->ParamCount)
           {
               ACPI_WARNING ((AE_INFO,
                   "Excess arguments (%u) - only %u are required",
                   Info->ParamCount,
                   Info->ObjDesc->Method.ParamCount));
   
               /* Just pass the required number of arguments */
   
               Info->ParamCount = Info->ObjDesc->Method.ParamCount;
           }
   
           /*
            * Any incoming external objects to be passed as arguments to the
            * method must be converted to internal objects
            */
           if (Info->ParamCount)
           {
               /*
                * Allocate a new parameter block for the internal objects
                * Add 1 to count to allow for null terminated internal list
                */
               Info->Parameters = ACPI_ALLOCATE_ZEROED (
                   ((ACPI_SIZE) Info->ParamCount + 1) * sizeof (void *));
               if (!Info->Parameters)
               {
                   Status = AE_NO_MEMORY;
                   goto Cleanup;
               }
   
               /* Convert each external object in the list to an internal object */
   
               for (i = 0; i < Info->ParamCount; i++)
               {
                   Status = AcpiUtCopyEobjectToIobject (
                       &ExternalParams->Pointer[i], &Info->Parameters[i]);
                   if (ACPI_FAILURE (Status))
                   {
                       goto Cleanup;
                   }
               }
   
               Info->Parameters[Info->ParamCount] = NULL;
           }
           break;
   
       default:
   
           /* Warn if arguments passed to an object that is not a method */
   
           if (Info->ParamCount)
           {
               ACPI_WARNING ((AE_INFO,
                   "%u arguments were passed to a non-method ACPI object",
                   Info->ParamCount));
           }
           break;
       }
   
   #endif
   
   
       /* Now we can evaluate the object */
   
       Status = AcpiNsEvaluate (Info);
   
       /*
        * If we are expecting a return value, and all went well above,
        * copy the return value to an external object.
        */
       if (!ReturnBuffer)
       {
           goto CleanupReturnObject;
       }
   
       if (!Info->ReturnObject)
       {
           ReturnBuffer->Length = 0;
           goto Cleanup;
       }
   
       if (ACPI_GET_DESCRIPTOR_TYPE (Info->ReturnObject) ==
           ACPI_DESC_TYPE_NAMED)
       {
           /*
            * If we received a NS Node as a return object, this means that
            * the object we are evaluating has nothing interesting to
            * return (such as a mutex, etc.)  We return an error because
            * these types are essentially unsupported by this interface.
            * We don't check up front because this makes it easier to add
            * support for various types at a later date if necessary.
            */
           Status = AE_TYPE;
           Info->ReturnObject = NULL;   /* No need to delete a NS Node */
           ReturnBuffer->Length = 0;
       }
   
       if (ACPI_FAILURE (Status))
       {
           goto CleanupReturnObject;
       }
   
       /* Dereference Index and RefOf references */
   
       AcpiNsResolveReferences (Info);
   
       /* Get the size of the returned object */
   
       Status = AcpiUtGetObjectSize (Info->ReturnObject,
           &BufferSpaceNeeded);
       if (ACPI_SUCCESS (Status))
       {
           /* Validate/Allocate/Clear caller buffer */
   
           Status = AcpiUtInitializeBuffer (ReturnBuffer,
               BufferSpaceNeeded);
           if (ACPI_FAILURE (Status))
           {
               /*
                * Caller's buffer is too small or a new one can't
                * be allocated
                */
               ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
                   "Needed buffer size %X, %s\n",
                   (UINT32) BufferSpaceNeeded,
                   AcpiFormatException (Status)));
           }
           else
           {
               /* We have enough space for the object, build it */
   
               Status = AcpiUtCopyIobjectToEobject (
                   Info->ReturnObject, ReturnBuffer);
           }
       }
   
   CleanupReturnObject:
   
       if (Info->ReturnObject)
       {
           /*
            * Delete the internal return object. NOTE: Interpreter must be
            * locked to avoid race condition.
            */
           AcpiExEnterInterpreter ();
   
           /* Remove one reference on the return object (should delete it) */
   
           AcpiUtRemoveReference (Info->ReturnObject);
           AcpiExExitInterpreter ();
       }
   
   
   Cleanup:
   
       /* Free the input parameter list (if we created one) */
   
       if (Info->Parameters)
       {
           /* Free the allocated parameter block */
   
           AcpiUtDeleteInternalObjectList (Info->Parameters);
       }
   
       ACPI_FREE (Info);
       return_ACPI_STATUS (Status);
   }
   
   ACPI_EXPORT_SYMBOL (AcpiEvaluateObject)
   
   
   /*******************************************************************************
    *
    * FUNCTION:    AcpiNsResolveReferences
    *
    * PARAMETERS:  Info                    - Evaluation info block
    *
    * RETURN:      Info->ReturnObject is replaced with the dereferenced object
    *
    * DESCRIPTION: Dereference certain reference objects. Called before an
    *              internal return object is converted to an external ACPI_OBJECT.
    *
    * Performs an automatic dereference of Index and RefOf reference objects.
    * These reference objects are not supported by the ACPI_OBJECT, so this is a
    * last resort effort to return something useful. Also, provides compatibility
    * with other ACPI implementations.
    *
    * NOTE: does not handle references within returned package objects or nested
    * references, but this support could be added later if found to be necessary.
    *
    ******************************************************************************/
   
   static void
   AcpiNsResolveReferences (
       ACPI_EVALUATE_INFO      *Info)
   {
       ACPI_OPERAND_OBJECT     *ObjDesc = NULL;
       ACPI_NAMESPACE_NODE     *Node;
   
   
       /* We are interested in reference objects only */
   
       if ((Info->ReturnObject)->Common.Type != ACPI_TYPE_LOCAL_REFERENCE)
       {
           return;
       }
   
       /*
        * Two types of references are supported - those created by Index and
        * RefOf operators. A name reference (AML_NAMEPATH_OP) can be converted
        * to an ACPI_OBJECT, so it is not dereferenced here. A DdbHandle
        * (AML_LOAD_OP) cannot be dereferenced, nor can it be converted to
        * an ACPI_OBJECT.
        */
       switch (Info->ReturnObject->Reference.Class)
       {
       case ACPI_REFCLASS_INDEX:
   
           ObjDesc = *(Info->ReturnObject->Reference.Where);
           break;
   
       case ACPI_REFCLASS_REFOF:
   
           Node = Info->ReturnObject->Reference.Object;
           if (Node)
           {
               ObjDesc = Node->Object;
           }
           break;
   
       default:
   
           return;
       }
   
       /* Replace the existing reference object */
   
       if (ObjDesc)
       {
           AcpiUtAddReference (ObjDesc);
           AcpiUtRemoveReference (Info->ReturnObject);
           Info->ReturnObject = ObjDesc;
       }
   
       return;
   }
   
   
   /*******************************************************************************
    *
    * FUNCTION:    AcpiWalkNamespace
    *
    * PARAMETERS:  Type                - ACPI_OBJECT_TYPE to search for
    *              StartObject         - Handle in namespace where search begins
    *              MaxDepth            - Depth to which search is to reach
    *              DescendingCallback  - Called during tree descent
    *                                    when an object of "Type" is found
    *              AscendingCallback   - Called during tree ascent
    *                                    when an object of "Type" is found
    *              Context             - Passed to user function(s) above
    *              ReturnValue         - Location where return value of
    *                                    UserFunction is put if terminated early
    *
    * RETURNS      Return value from the UserFunction if terminated early.
    *              Otherwise, returns NULL.
    *
    * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
    *              starting (and ending) at the object specified by StartHandle.
    *              The callback function is called whenever an object that matches
    *              the type parameter is found. If the callback function returns
    *              a non-zero value, the search is terminated immediately and this
    *              value is returned to the caller.
    *
    *              The point of this procedure is to provide a generic namespace
    *              walk routine that can be called from multiple places to
    *              provide multiple services; the callback function(s) can be
    *              tailored to each task, whether it is a print function,
    *              a compare function, etc.
    *
    ******************************************************************************/
   
   ACPI_STATUS
   AcpiWalkNamespace (
       ACPI_OBJECT_TYPE        Type,
       ACPI_HANDLE             StartObject,
       UINT32                  MaxDepth,
       ACPI_WALK_CALLBACK      DescendingCallback,
       ACPI_WALK_CALLBACK      AscendingCallback,
       void                    *Context,
       void                    **ReturnValue)
   {
       ACPI_STATUS             Status;
   
   
       ACPI_FUNCTION_TRACE (AcpiWalkNamespace);
   
   
       /* Parameter validation */
   
       if ((Type > ACPI_TYPE_LOCAL_MAX) ||
           (!MaxDepth)                  ||
           (!DescendingCallback && !AscendingCallback))
       {
           return_ACPI_STATUS (AE_BAD_PARAMETER);
       }
   
       /*
        * Need to acquire the namespace reader lock to prevent interference
        * with any concurrent table unloads (which causes the deletion of
        * namespace objects). We cannot allow the deletion of a namespace node
        * while the user function is using it. The exception to this are the
        * nodes created and deleted during control method execution -- these
        * nodes are marked as temporary nodes and are ignored by the namespace
        * walk. Thus, control methods can be executed while holding the
        * namespace deletion lock (and the user function can execute control
        * methods.)
        */
       Status = AcpiUtAcquireReadLock (&AcpiGbl_NamespaceRwLock);
       if (ACPI_FAILURE (Status))
       {
           return_ACPI_STATUS (Status);
       }
   
       /*
        * Lock the namespace around the walk. The namespace will be
        * unlocked/locked around each call to the user function - since the user
        * function must be allowed to make ACPICA calls itself (for example, it
        * will typically execute control methods during device enumeration.)
        */
       Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
       if (ACPI_FAILURE (Status))
       {
           goto UnlockAndExit;
       }
   
       /* Now we can validate the starting node */
   
       if (!AcpiNsValidateHandle (StartObject))
       {
           Status = AE_BAD_PARAMETER;
           goto UnlockAndExit2;
       }
   
       Status = AcpiNsWalkNamespace (Type, StartObject, MaxDepth,
           ACPI_NS_WALK_UNLOCK, DescendingCallback,
           AscendingCallback, Context, ReturnValue);
   
   UnlockAndExit2:
       (void) AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
   
   UnlockAndExit:
       (void) AcpiUtReleaseReadLock (&AcpiGbl_NamespaceRwLock);
       return_ACPI_STATUS (Status);
   }
   
   ACPI_EXPORT_SYMBOL (AcpiWalkNamespace)
   
   
   /*******************************************************************************
    *
    * FUNCTION:    AcpiNsGetDeviceCallback
    *
    * PARAMETERS:  Callback from AcpiGetDevice
    *
    * RETURN:      Status
    *
    * DESCRIPTION: Takes callbacks from WalkNamespace and filters out all non-
    *              present devices, or if they specified a HID, it filters based
    *              on that.
    *
    ******************************************************************************/
   
   static ACPI_STATUS
   AcpiNsGetDeviceCallback (
       ACPI_HANDLE             ObjHandle,
       UINT32                  NestingLevel,
       void                    *Context,
       void                    **ReturnValue)
   {
       ACPI_GET_DEVICES_INFO   *Info = Context;
       ACPI_STATUS             Status;
       ACPI_NAMESPACE_NODE     *Node;
       UINT32                  Flags;
       ACPI_PNP_DEVICE_ID      *Hid;
       ACPI_PNP_DEVICE_ID_LIST *Cid;
       UINT32                  i;
       BOOLEAN                 Found;
       int                     NoMatch;
   
   
       Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
       if (ACPI_FAILURE (Status))
       {
           return (Status);
       }
   
       Node = AcpiNsValidateHandle (ObjHandle);
       Status = AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
       if (ACPI_FAILURE (Status))
       {
           return (Status);
       }
   
       if (!Node)
       {
           return (AE_BAD_PARAMETER);
       }
   
       /*
        * First, filter based on the device HID and CID.
        *
        * 01/2010: For this case where a specific HID is requested, we don't
        * want to run _STA until we have an actual HID match. Thus, we will
        * not unnecessarily execute _STA on devices for which the caller
        * doesn't care about. Previously, _STA was executed unconditionally
        * on all devices found here.
        *
        * A side-effect of this change is that now we will continue to search
        * for a matching HID even under device trees where the parent device
        * would have returned a _STA that indicates it is not present or
        * not functioning (thus aborting the search on that branch).
        */
       if (Info->Hid != NULL)
       {
           Status = AcpiUtExecute_HID (Node, &Hid);
           if (Status == AE_NOT_FOUND)
           {
               return (AE_OK);
           }
           else if (ACPI_FAILURE (Status))
           {
               return (AE_CTRL_DEPTH);
           }
   
           NoMatch = strcmp (Hid->String, Info->Hid);
           ACPI_FREE (Hid);
   
           if (NoMatch)
           {
               /*
                * HID does not match, attempt match within the
                * list of Compatible IDs (CIDs)
                */
               Status = AcpiUtExecute_CID (Node, &Cid);
               if (Status == AE_NOT_FOUND)
               {
                   return (AE_OK);
               }
               else if (ACPI_FAILURE (Status))
               {
                   return (AE_CTRL_DEPTH);
               }
   
               /* Walk the CID list */
   
               Found = FALSE;
               for (i = 0; i < Cid->Count; i++)
               {
                   if (strcmp (Cid->Ids[i].String, Info->Hid) == 0)
                   {
                       /* Found a matching CID */
   
                       Found = TRUE;
                       break;
                   }
               }
   
               ACPI_FREE (Cid);
               if (!Found)
               {
                   return (AE_OK);
               }
           }
       }
   
       /* Run _STA to determine if device is present */
   
       Status = AcpiUtExecute_STA (Node, &Flags);
       if (ACPI_FAILURE (Status))
       {
           return (AE_CTRL_DEPTH);
       }
   
       if (!(Flags & ACPI_STA_DEVICE_PRESENT) &&
           !(Flags & ACPI_STA_DEVICE_FUNCTIONING))
       {
           /*
            * Don't examine the children of the device only when the
            * device is neither present nor functional. See ACPI spec,
            * description of _STA for more information.
            */
           return (AE_CTRL_DEPTH);
       }
   
       /* We have a valid device, invoke the user function */
   
       Status = Info->UserFunction (ObjHandle, NestingLevel,
           Info->Context, ReturnValue);
       return (Status);
   }
   
   
   /*******************************************************************************
    *
    * FUNCTION:    AcpiGetDevices
    *
    * PARAMETERS:  HID                 - HID to search for. Can be NULL.
    *              UserFunction        - Called when a matching object is found
    *              Context             - Passed to user function
    *              ReturnValue         - Location where return value of
    *                                    UserFunction is put if terminated early
    *
    * RETURNS      Return value from the UserFunction if terminated early.
    *              Otherwise, returns NULL.
    *
    * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
    *              starting (and ending) at the object specified by StartHandle.
    *              The UserFunction is called whenever an object of type
    *              Device is found. If the user function returns
    *              a non-zero value, the search is terminated immediately and this
    *              value is returned to the caller.
    *
    *              This is a wrapper for WalkNamespace, but the callback performs
    *              additional filtering. Please see AcpiNsGetDeviceCallback.
    *
    ******************************************************************************/
   
   ACPI_STATUS
   AcpiGetDevices (
       char                    *HID,
       ACPI_WALK_CALLBACK      UserFunction,
       void                    *Context,
       void                    **ReturnValue)
   {
      ACPI_STATUS             Status;
      ACPI_GET_DEVICES_INFO   Info;
  
  
      ACPI_FUNCTION_TRACE (AcpiGetDevices);
  
  
      /* Parameter validation */
  
      if (!UserFunction)
      {
          return_ACPI_STATUS (AE_BAD_PARAMETER);
      }
  
      /*
       * We're going to call their callback from OUR callback, so we need
       * to know what it is, and their context parameter.
       */
      Info.Hid = HID;
      Info.Context = Context;
      Info.UserFunction = UserFunction;
  
      /*
       * Lock the namespace around the walk.
       * The namespace will be unlocked/locked around each call
       * to the user function - since this function
       * must be allowed to make Acpi calls itself.
       */
      Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
      if (ACPI_FAILURE (Status))
      {
          return_ACPI_STATUS (Status);
      }
  
      Status = AcpiNsWalkNamespace (ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
          ACPI_UINT32_MAX, ACPI_NS_WALK_UNLOCK,
          AcpiNsGetDeviceCallback, NULL, &Info, ReturnValue);
  
      (void) AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
      return_ACPI_STATUS (Status);
  }
  
  ACPI_EXPORT_SYMBOL (AcpiGetDevices)
  
  
  /*******************************************************************************
   *
   * FUNCTION:    AcpiAttachData
   *
   * PARAMETERS:  ObjHandle           - Namespace node
   *              Handler             - Handler for this attachment
   *              Data                - Pointer to data to be attached
   *
   * RETURN:      Status
   *
   * DESCRIPTION: Attach arbitrary data and handler to a namespace node.
   *
   ******************************************************************************/
  
  ACPI_STATUS
  AcpiAttachData (
      ACPI_HANDLE             ObjHandle,
      ACPI_OBJECT_HANDLER     Handler,
      void                    *Data)
  {
      ACPI_NAMESPACE_NODE     *Node;
      ACPI_STATUS             Status;
  
  
      /* Parameter validation */
  
      if (!ObjHandle  ||
          !Handler    ||
          !Data)
      {
          return (AE_BAD_PARAMETER);
      }
  
      Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
      if (ACPI_FAILURE (Status))
      {
          return (Status);
      }
  
      /* Convert and validate the handle */
  
      Node = AcpiNsValidateHandle (ObjHandle);
      if (!Node)
      {
          Status = AE_BAD_PARAMETER;
          goto UnlockAndExit;
      }
  
      Status = AcpiNsAttachData (Node, Handler, Data);
  
  UnlockAndExit:
      (void) AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
      return (Status);
  }
  
  ACPI_EXPORT_SYMBOL (AcpiAttachData)
  
  
  /*******************************************************************************
   *
   * FUNCTION:    AcpiDetachData
   *
   * PARAMETERS:  ObjHandle           - Namespace node handle
   *              Handler             - Handler used in call to AcpiAttachData
   *
   * RETURN:      Status
   *
   * DESCRIPTION: Remove data that was previously attached to a node.
   *
   ******************************************************************************/
  
  ACPI_STATUS
  AcpiDetachData (
      ACPI_HANDLE             ObjHandle,
      ACPI_OBJECT_HANDLER     Handler)
  {
      ACPI_NAMESPACE_NODE     *Node;
      ACPI_STATUS             Status;
  
  
      /* Parameter validation */
  
      if (!ObjHandle  ||
          !Handler)
      {
          return (AE_BAD_PARAMETER);
      }
  
      Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
      if (ACPI_FAILURE (Status))
      {
          return (Status);
      }
  
      /* Convert and validate the handle */
  
      Node = AcpiNsValidateHandle (ObjHandle);
      if (!Node)
      {
          Status = AE_BAD_PARAMETER;
          goto UnlockAndExit;
      }
  
      Status = AcpiNsDetachData (Node, Handler);
  
  UnlockAndExit:
      (void) AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
      return (Status);
  }
  
  ACPI_EXPORT_SYMBOL (AcpiDetachData)
  
  
  /*******************************************************************************
   *
   * FUNCTION:    AcpiGetData
   *
   * PARAMETERS:  ObjHandle           - Namespace node
   *              Handler             - Handler used in call to AttachData
   *              Data                - Where the data is returned
   *
   * RETURN:      Status
   *
   * DESCRIPTION: Retrieve data that was previously attached to a namespace node.
   *
   ******************************************************************************/
  
  ACPI_STATUS
  AcpiGetData (
      ACPI_HANDLE             ObjHandle,
      ACPI_OBJECT_HANDLER     Handler,
      void                    **Data)
  {
      ACPI_NAMESPACE_NODE     *Node;
      ACPI_STATUS             Status;
  
  
      /* Parameter validation */
  
      if (!ObjHandle  ||
          !Handler    ||
          !Data)
      {
          return (AE_BAD_PARAMETER);
      }
  
      Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
      if (ACPI_FAILURE (Status))
      {
          return (Status);
      }
  
      /* Convert and validate the handle */
  
      Node = AcpiNsValidateHandle (ObjHandle);
      if (!Node)
      {
          Status = AE_BAD_PARAMETER;
          goto UnlockAndExit;
      }
  
      Status = AcpiNsGetAttachedData (Node, Handler, Data);
  
  UnlockAndExit:
      (void) AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
      return (Status);
  }
  
  ACPI_EXPORT_SYMBOL (AcpiGetData)

Cache object: 69e16dcb8d3fe50de3a13d4fe39d3467