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      1 /******************************************************************************
      2  *
      3  * Module Name: evhandler - Support for Address Space handlers
      4  *
      5  *****************************************************************************/
      6 
      7 /******************************************************************************
      8  *
      9  * 1. Copyright Notice
     10  *
     11  * Some or all of this work - Copyright (c) 1999 - 2025, Intel Corp.
     12  * All rights reserved.
     13  *
     14  * 2. License
     15  *
     16  * 2.1. This is your license from Intel Corp. under its intellectual property
     17  * rights. You may have additional license terms from the party that provided
     18  * you this software, covering your right to use that party's intellectual
     19  * property rights.
     20  *
     21  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
     22  * copy of the source code appearing in this file ("Covered Code") an
     23  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
     24  * base code distributed originally by Intel ("Original Intel Code") to copy,
     25  * make derivatives, distribute, use and display any portion of the Covered
     26  * Code in any form, with the right to sublicense such rights; and
     27  *
     28  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
     29  * license (with the right to sublicense), under only those claims of Intel
     30  * patents that are infringed by the Original Intel Code, to make, use, sell,
     31  * offer to sell, and import the Covered Code and derivative works thereof
     32  * solely to the minimum extent necessary to exercise the above copyright
     33  * license, and in no event shall the patent license extend to any additions
     34  * to or modifications of the Original Intel Code. No other license or right
     35  * is granted directly or by implication, estoppel or otherwise;
     36  *
     37  * The above copyright and patent license is granted only if the following
     38  * conditions are met:
     39  *
     40  * 3. Conditions
     41  *
     42  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
     43  * Redistribution of source code of any substantial portion of the Covered
     44  * Code or modification with rights to further distribute source must include
     45  * the above Copyright Notice, the above License, this list of Conditions,
     46  * and the following Disclaimer and Export Compliance provision. In addition,
     47  * Licensee must cause all Covered Code to which Licensee contributes to
     48  * contain a file documenting the changes Licensee made to create that Covered
     49  * Code and the date of any change. Licensee must include in that file the
     50  * documentation of any changes made by any predecessor Licensee. Licensee
     51  * must include a prominent statement that the modification is derived,
     52  * directly or indirectly, from Original Intel Code.
     53  *
     54  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
     55  * Redistribution of source code of any substantial portion of the Covered
     56  * Code or modification without rights to further distribute source must
     57  * include the following Disclaimer and Export Compliance provision in the
     58  * documentation and/or other materials provided with distribution. In
     59  * addition, Licensee may not authorize further sublicense of source of any
     60  * portion of the Covered Code, and must include terms to the effect that the
     61  * license from Licensee to its licensee is limited to the intellectual
     62  * property embodied in the software Licensee provides to its licensee, and
     63  * not to intellectual property embodied in modifications its licensee may
     64  * make.
     65  *
     66  * 3.3. Redistribution of Executable. Redistribution in executable form of any
     67  * substantial portion of the Covered Code or modification must reproduce the
     68  * above Copyright Notice, and the following Disclaimer and Export Compliance
     69  * provision in the documentation and/or other materials provided with the
     70  * distribution.
     71  *
     72  * 3.4. Intel retains all right, title, and interest in and to the Original
     73  * Intel Code.
     74  *
     75  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
     76  * Intel shall be used in advertising or otherwise to promote the sale, use or
     77  * other dealings in products derived from or relating to the Covered Code
     78  * without prior written authorization from Intel.
     79  *
     80  * 4. Disclaimer and Export Compliance
     81  *
     82  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
     83  * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
     84  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE,
     85  * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY
     86  * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY
     87  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
     88  * PARTICULAR PURPOSE.
     89  *
     90  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
     91  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
     92  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
     93  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
     94  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
     95  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS
     96  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
     97  * LIMITED REMEDY.
     98  *
     99  * 4.3. Licensee shall not export, either directly or indirectly, any of this
    100  * software or system incorporating such software without first obtaining any
    101  * required license or other approval from the U. S. Department of Commerce or
    102  * any other agency or department of the United States Government. In the
    103  * event Licensee exports any such software from the United States or
    104  * re-exports any such software from a foreign destination, Licensee shall
    105  * ensure that the distribution and export/re-export of the software is in
    106  * compliance with all laws, regulations, orders, or other restrictions of the
    107  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
    108  * any of its subsidiaries will export/re-export any technical data, process,
    109  * software, or service, directly or indirectly, to any country for which the
    110  * United States government or any agency thereof requires an export license,
    111  * other governmental approval, or letter of assurance, without first obtaining
    112  * such license, approval or letter.
    113  *
    114  *****************************************************************************
    115  *
    116  * Alternatively, you may choose to be licensed under the terms of the
    117  * following license:
    118  *
    119  * Redistribution and use in source and binary forms, with or without
    120  * modification, are permitted provided that the following conditions
    121  * are met:
    122  * 1. Redistributions of source code must retain the above copyright
    123  *    notice, this list of conditions, and the following disclaimer,
    124  *    without modification.
    125  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
    126  *    substantially similar to the "NO WARRANTY" disclaimer below
    127  *    ("Disclaimer") and any redistribution must be conditioned upon
    128  *    including a substantially similar Disclaimer requirement for further
    129  *    binary redistribution.
    130  * 3. Neither the names of the above-listed copyright holders nor the names
    131  *    of any contributors may be used to endorse or promote products derived
    132  *    from this software without specific prior written permission.
    133  *
    134  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
    135  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
    136  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
    137  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
    138  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
    139  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
    140  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
    141  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
    142  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
    143  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
    144  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
    145  *
    146  * Alternatively, you may choose to be licensed under the terms of the
    147  * GNU General Public License ("GPL") version 2 as published by the Free
    148  * Software Foundation.
    149  *
    150  *****************************************************************************/
    151 
    152 #include "acpi.h"
    153 #include "accommon.h"
    154 #include "acevents.h"
    155 #include "acnamesp.h"
    156 #include "acinterp.h"
    157 
    158 #define _COMPONENT          ACPI_EVENTS
    159         ACPI_MODULE_NAME    ("evhandler")
    160 
    161 
    162 /* Local prototypes */
    163 
    164 static ACPI_STATUS
    165 AcpiEvInstallHandler (
    166     ACPI_HANDLE             ObjHandle,
    167     UINT32                  Level,
    168     void                    *Context,
    169     void                    **ReturnValue);
    170 
    171 
    172 /* These are the address spaces that will get default handlers */
    173 
    174 UINT8        AcpiGbl_DefaultAddressSpaces[ACPI_NUM_DEFAULT_SPACES] =
    175 {
    176     ACPI_ADR_SPACE_SYSTEM_MEMORY,
    177     ACPI_ADR_SPACE_SYSTEM_IO,
    178     ACPI_ADR_SPACE_PCI_CONFIG,
    179     ACPI_ADR_SPACE_DATA_TABLE
    180 };
    181 
    182 
    183 /*******************************************************************************
    184  *
    185  * FUNCTION:    AcpiEvInstallRegionHandlers
    186  *
    187  * PARAMETERS:  None
    188  *
    189  * RETURN:      Status
    190  *
    191  * DESCRIPTION: Installs the core subsystem default address space handlers.
    192  *
    193  ******************************************************************************/
    194 
    195 ACPI_STATUS
    196 AcpiEvInstallRegionHandlers (
    197     void)
    198 {
    199     ACPI_STATUS             Status;
    200     UINT32                  i;
    201 
    202 
    203     ACPI_FUNCTION_TRACE (EvInstallRegionHandlers);
    204 
    205 
    206     Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
    207     if (ACPI_FAILURE (Status))
    208     {
    209         return_ACPI_STATUS (Status);
    210     }
    211 
    212     /*
    213      * All address spaces (PCI Config, EC, SMBus) are scope dependent and
    214      * registration must occur for a specific device.
    215      *
    216      * In the case of the system memory and IO address spaces there is
    217      * currently no device associated with the address space. For these we
    218      * use the root.
    219      *
    220      * We install the default PCI config space handler at the root so that
    221      * this space is immediately available even though the we have not
    222      * enumerated all the PCI Root Buses yet. This is to conform to the ACPI
    223      * specification which states that the PCI config space must be always
    224      * available -- even though we are nowhere near ready to find the PCI root
    225      * buses at this point.
    226      *
    227      * NOTE: We ignore AE_ALREADY_EXISTS because this means that a handler
    228      * has already been installed (via AcpiInstallAddressSpaceHandler).
    229      * Similar for AE_SAME_HANDLER.
    230      */
    231     for (i = 0; i < ACPI_NUM_DEFAULT_SPACES; i++)
    232     {
    233         Status = AcpiEvInstallSpaceHandler (AcpiGbl_RootNode,
    234             AcpiGbl_DefaultAddressSpaces[i],
    235             ACPI_DEFAULT_HANDLER, NULL, NULL);
    236         switch (Status)
    237         {
    238         case AE_OK:
    239         case AE_SAME_HANDLER:
    240         case AE_ALREADY_EXISTS:
    241 
    242             /* These exceptions are all OK */
    243 
    244             Status = AE_OK;
    245             break;
    246 
    247         default:
    248 
    249             goto UnlockAndExit;
    250         }
    251     }
    252 
    253 UnlockAndExit:
    254     (void) AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
    255     return_ACPI_STATUS (Status);
    256 }
    257 
    258 
    259 /*******************************************************************************
    260  *
    261  * FUNCTION:    AcpiEvHasDefaultHandler
    262  *
    263  * PARAMETERS:  Node                - Namespace node for the device
    264  *              SpaceId             - The address space ID
    265  *
    266  * RETURN:      TRUE if default handler is installed, FALSE otherwise
    267  *
    268  * DESCRIPTION: Check if the default handler is installed for the requested
    269  *              space ID.
    270  *
    271  ******************************************************************************/
    272 
    273 BOOLEAN
    274 AcpiEvHasDefaultHandler (
    275     ACPI_NAMESPACE_NODE     *Node,
    276     ACPI_ADR_SPACE_TYPE     SpaceId)
    277 {
    278     ACPI_OPERAND_OBJECT     *ObjDesc;
    279     ACPI_OPERAND_OBJECT     *HandlerObj;
    280 
    281 
    282     /* Must have an existing internal object */
    283 
    284     ObjDesc = AcpiNsGetAttachedObject (Node);
    285     if (ObjDesc)
    286     {
    287         HandlerObj = ObjDesc->CommonNotify.Handler;
    288 
    289         /* Walk the linked list of handlers for this object */
    290 
    291         while (HandlerObj)
    292         {
    293             if (HandlerObj->AddressSpace.SpaceId == SpaceId)
    294             {
    295                 if (HandlerObj->AddressSpace.HandlerFlags &
    296                     ACPI_ADDR_HANDLER_DEFAULT_INSTALLED)
    297                 {
    298                     return (TRUE);
    299                 }
    300             }
    301 
    302             HandlerObj = HandlerObj->AddressSpace.Next;
    303         }
    304     }
    305 
    306     return (FALSE);
    307 }
    308 
    309 
    310 /*******************************************************************************
    311  *
    312  * FUNCTION:    AcpiEvInstallHandler
    313  *
    314  * PARAMETERS:  WalkNamespace callback
    315  *
    316  * DESCRIPTION: This routine installs an address handler into objects that are
    317  *              of type Region or Device.
    318  *
    319  *              If the Object is a Device, and the device has a handler of
    320  *              the same type then the search is terminated in that branch.
    321  *
    322  *              This is because the existing handler is closer in proximity
    323  *              to any more regions than the one we are trying to install.
    324  *
    325  ******************************************************************************/
    326 
    327 static ACPI_STATUS
    328 AcpiEvInstallHandler (
    329     ACPI_HANDLE             ObjHandle,
    330     UINT32                  Level,
    331     void                    *Context,
    332     void                    **ReturnValue)
    333 {
    334     ACPI_OPERAND_OBJECT     *HandlerObj;
    335     ACPI_OPERAND_OBJECT     *NextHandlerObj;
    336     ACPI_OPERAND_OBJECT     *ObjDesc;
    337     ACPI_NAMESPACE_NODE     *Node;
    338     ACPI_STATUS             Status;
    339 
    340 
    341     ACPI_FUNCTION_NAME (EvInstallHandler);
    342 
    343 
    344     HandlerObj = (ACPI_OPERAND_OBJECT  *) Context;
    345 
    346     /* Parameter validation */
    347 
    348     if (!HandlerObj)
    349     {
    350         return (AE_OK);
    351     }
    352 
    353     /* Convert and validate the device handle */
    354 
    355     Node = AcpiNsValidateHandle (ObjHandle);
    356     if (!Node)
    357     {
    358         return (AE_BAD_PARAMETER);
    359     }
    360 
    361     /*
    362      * We only care about regions and objects that are allowed to have
    363      * address space handlers
    364      */
    365     if ((Node->Type != ACPI_TYPE_DEVICE) &&
    366         (Node->Type != ACPI_TYPE_REGION) &&
    367         (Node != AcpiGbl_RootNode))
    368     {
    369         return (AE_OK);
    370     }
    371 
    372     /* Check for an existing internal object */
    373 
    374     ObjDesc = AcpiNsGetAttachedObject (Node);
    375     if (!ObjDesc)
    376     {
    377         /* No object, just exit */
    378 
    379         return (AE_OK);
    380     }
    381 
    382     /* Devices are handled different than regions */
    383 
    384     if (ObjDesc->Common.Type == ACPI_TYPE_DEVICE)
    385     {
    386         /* Check if this Device already has a handler for this address space */
    387 
    388         NextHandlerObj = AcpiEvFindRegionHandler (
    389             HandlerObj->AddressSpace.SpaceId, ObjDesc->CommonNotify.Handler);
    390         if (NextHandlerObj)
    391         {
    392             /* Found a handler, is it for the same address space? */
    393 
    394             ACPI_DEBUG_PRINT ((ACPI_DB_OPREGION,
    395                 "Found handler for region [%s] in device %p(%p) handler %p\n",
    396                 AcpiUtGetRegionName (HandlerObj->AddressSpace.SpaceId),
    397                 ObjDesc, NextHandlerObj, HandlerObj));
    398 
    399             /*
    400              * Since the object we found it on was a device, then it means
    401              * that someone has already installed a handler for the branch
    402              * of the namespace from this device on. Just bail out telling
    403              * the walk routine to not traverse this branch. This preserves
    404              * the scoping rule for handlers.
    405              */
    406             return (AE_CTRL_DEPTH);
    407         }
    408 
    409         /*
    410          * As long as the device didn't have a handler for this space we
    411          * don't care about it. We just ignore it and proceed.
    412          */
    413         return (AE_OK);
    414     }
    415 
    416     /* Object is a Region */
    417 
    418     if (ObjDesc->Region.SpaceId != HandlerObj->AddressSpace.SpaceId)
    419     {
    420         /* This region is for a different address space, just ignore it */
    421 
    422         return (AE_OK);
    423     }
    424 
    425     /*
    426      * Now we have a region and it is for the handler's address space type.
    427      *
    428      * First disconnect region for any previous handler (if any)
    429      */
    430     AcpiEvDetachRegion (ObjDesc, FALSE);
    431 
    432     /* Connect the region to the new handler */
    433 
    434     Status = AcpiEvAttachRegion (HandlerObj, ObjDesc, FALSE);
    435     return (Status);
    436 }
    437 
    438 
    439 /*******************************************************************************
    440  *
    441  * FUNCTION:    AcpiEvFindRegionHandler
    442  *
    443  * PARAMETERS:  SpaceId         - The address space ID
    444  *              HandlerObj      - Head of the handler object list
    445  *
    446  * RETURN:      Matching handler object. NULL if space ID not matched
    447  *
    448  * DESCRIPTION: Search a handler object list for a match on the address
    449  *              space ID.
    450  *
    451  ******************************************************************************/
    452 
    453 ACPI_OPERAND_OBJECT *
    454 AcpiEvFindRegionHandler (
    455     ACPI_ADR_SPACE_TYPE     SpaceId,
    456     ACPI_OPERAND_OBJECT     *HandlerObj)
    457 {
    458 
    459     /* Walk the handler list for this device */
    460 
    461     while (HandlerObj)
    462     {
    463         /* Same SpaceId indicates a handler is installed */
    464 
    465         if (HandlerObj->AddressSpace.SpaceId == SpaceId)
    466         {
    467             return (HandlerObj);
    468         }
    469 
    470         /* Next handler object */
    471 
    472         HandlerObj = HandlerObj->AddressSpace.Next;
    473     }
    474 
    475     return (NULL);
    476 }
    477 
    478 
    479 /*******************************************************************************
    480  *
    481  * FUNCTION:    AcpiEvInstallSpaceHandler
    482  *
    483  * PARAMETERS:  Node            - Namespace node for the device
    484  *              SpaceId         - The address space ID
    485  *              Handler         - Address of the handler
    486  *              Setup           - Address of the setup function
    487  *              Context         - Value passed to the handler on each access
    488  *
    489  * RETURN:      Status
    490  *
    491  * DESCRIPTION: Install a handler for all OpRegions of a given SpaceId.
    492  *              Assumes namespace is locked
    493  *
    494  ******************************************************************************/
    495 
    496 ACPI_STATUS
    497 AcpiEvInstallSpaceHandler (
    498     ACPI_NAMESPACE_NODE     *Node,
    499     ACPI_ADR_SPACE_TYPE     SpaceId,
    500     ACPI_ADR_SPACE_HANDLER  Handler,
    501     ACPI_ADR_SPACE_SETUP    Setup,
    502     void                    *Context)
    503 {
    504     ACPI_OPERAND_OBJECT     *ObjDesc;
    505     ACPI_OPERAND_OBJECT     *HandlerObj;
    506     ACPI_STATUS             Status = AE_OK;
    507     ACPI_OBJECT_TYPE        Type;
    508     UINT8                   Flags = 0;
    509 
    510 
    511     ACPI_FUNCTION_TRACE (EvInstallSpaceHandler);
    512 
    513 
    514     /*
    515      * This registration is valid for only the types below and the root.
    516      * The root node is where the default handlers get installed.
    517      */
    518     if ((Node->Type != ACPI_TYPE_DEVICE)     &&
    519         (Node->Type != ACPI_TYPE_PROCESSOR)  &&
    520         (Node->Type != ACPI_TYPE_THERMAL)    &&
    521         (Node != AcpiGbl_RootNode))
    522     {
    523         Status = AE_BAD_PARAMETER;
    524         goto UnlockAndExit;
    525     }
    526 
    527     if (Handler == ACPI_DEFAULT_HANDLER)
    528     {
    529         Flags = ACPI_ADDR_HANDLER_DEFAULT_INSTALLED;
    530 
    531         switch (SpaceId)
    532         {
    533         case ACPI_ADR_SPACE_SYSTEM_MEMORY:
    534 
    535             Handler = AcpiExSystemMemorySpaceHandler;
    536             Setup   = AcpiEvSystemMemoryRegionSetup;
    537             break;
    538 
    539         case ACPI_ADR_SPACE_SYSTEM_IO:
    540 
    541             Handler = AcpiExSystemIoSpaceHandler;
    542             Setup   = AcpiEvIoSpaceRegionSetup;
    543             break;
    544 
    545         case ACPI_ADR_SPACE_PCI_CONFIG:
    546 
    547             Handler = AcpiExPciConfigSpaceHandler;
    548             Setup   = AcpiEvPciConfigRegionSetup;
    549             break;
    550 
    551         case ACPI_ADR_SPACE_CMOS:
    552 
    553             Handler = AcpiExCmosSpaceHandler;
    554             Setup   = AcpiEvCmosRegionSetup;
    555             break;
    556 
    557         case ACPI_ADR_SPACE_PCI_BAR_TARGET:
    558 
    559             Handler = AcpiExPciBarSpaceHandler;
    560             Setup   = AcpiEvPciBarRegionSetup;
    561             break;
    562 
    563         case ACPI_ADR_SPACE_DATA_TABLE:
    564 
    565             Handler = AcpiExDataTableSpaceHandler;
    566             Setup   = AcpiEvDataTableRegionSetup;
    567             break;
    568 
    569         default:
    570 
    571             Status = AE_BAD_PARAMETER;
    572             goto UnlockAndExit;
    573         }
    574     }
    575 
    576     /* If the caller hasn't specified a setup routine, use the default */
    577 
    578     if (!Setup)
    579     {
    580         Setup = AcpiEvDefaultRegionSetup;
    581     }
    582 
    583     /* Check for an existing internal object */
    584 
    585     ObjDesc = AcpiNsGetAttachedObject (Node);
    586     if (ObjDesc)
    587     {
    588         /*
    589          * The attached device object already exists. Now make sure
    590          * the handler is not already installed.
    591          */
    592         HandlerObj = AcpiEvFindRegionHandler (SpaceId,
    593             ObjDesc->CommonNotify.Handler);
    594 
    595         if (HandlerObj)
    596         {
    597             if (HandlerObj->AddressSpace.Handler == Handler)
    598             {
    599                 /*
    600                  * It is (relatively) OK to attempt to install the SAME
    601                  * handler twice. This can easily happen with the
    602                  * PCI_Config space.
    603                  */
    604                 Status = AE_SAME_HANDLER;
    605                 goto UnlockAndExit;
    606             }
    607             else
    608             {
    609                 /* A handler is already installed */
    610 
    611                 Status = AE_ALREADY_EXISTS;
    612             }
    613 
    614             goto UnlockAndExit;
    615         }
    616     }
    617     else
    618     {
    619         ACPI_DEBUG_PRINT ((ACPI_DB_OPREGION,
    620             "Creating object on Device %p while installing handler\n",
    621             Node));
    622 
    623         /* ObjDesc does not exist, create one */
    624 
    625         if (Node->Type == ACPI_TYPE_ANY)
    626         {
    627             Type = ACPI_TYPE_DEVICE;
    628         }
    629         else
    630         {
    631             Type = Node->Type;
    632         }
    633 
    634         ObjDesc = AcpiUtCreateInternalObject (Type);
    635         if (!ObjDesc)
    636         {
    637             Status = AE_NO_MEMORY;
    638             goto UnlockAndExit;
    639         }
    640 
    641         /* Init new descriptor */
    642 
    643         ObjDesc->Common.Type = (UINT8) Type;
    644 
    645         /* Attach the new object to the Node */
    646 
    647         Status = AcpiNsAttachObject (Node, ObjDesc, Type);
    648 
    649         /* Remove local reference to the object */
    650 
    651         AcpiUtRemoveReference (ObjDesc);
    652 
    653         if (ACPI_FAILURE (Status))
    654         {
    655             goto UnlockAndExit;
    656         }
    657     }
    658 
    659     ACPI_DEBUG_PRINT ((ACPI_DB_OPREGION,
    660         "Installing address handler for region %s(%X) "
    661         "on Device %4.4s %p(%p)\n",
    662         AcpiUtGetRegionName (SpaceId), SpaceId,
    663         AcpiUtGetNodeName (Node), Node, ObjDesc));
    664 
    665     /*
    666      * Install the handler
    667      *
    668      * At this point there is no existing handler. Just allocate the object
    669      * for the handler and link it into the list.
    670      */
    671     HandlerObj = AcpiUtCreateInternalObject (ACPI_TYPE_LOCAL_ADDRESS_HANDLER);
    672     if (!HandlerObj)
    673     {
    674         Status = AE_NO_MEMORY;
    675         goto UnlockAndExit;
    676     }
    677 
    678     /* Init handler obj */
    679 
    680     Status = AcpiOsCreateMutex (&HandlerObj->AddressSpace.ContextMutex);
    681     if (ACPI_FAILURE (Status))
    682     {
    683         AcpiUtRemoveReference (HandlerObj);
    684         goto UnlockAndExit;
    685     }
    686 
    687     HandlerObj->AddressSpace.SpaceId = (UINT8) SpaceId;
    688     HandlerObj->AddressSpace.HandlerFlags = Flags;
    689     HandlerObj->AddressSpace.RegionList = NULL;
    690     HandlerObj->AddressSpace.Node = Node;
    691     HandlerObj->AddressSpace.Handler = Handler;
    692     HandlerObj->AddressSpace.Context = Context;
    693     HandlerObj->AddressSpace.Setup = Setup;
    694 
    695     /* Install at head of Device.AddressSpace list */
    696 
    697     HandlerObj->AddressSpace.Next = ObjDesc->CommonNotify.Handler;
    698 
    699     /*
    700      * The Device object is the first reference on the HandlerObj.
    701      * Each region that uses the handler adds a reference.
    702      */
    703     ObjDesc->CommonNotify.Handler = HandlerObj;
    704 
    705     /*
    706      * Walk the namespace finding all of the regions this handler will
    707      * manage.
    708      *
    709      * Start at the device and search the branch toward the leaf nodes
    710      * until either the leaf is encountered or a device is detected that
    711      * has an address handler of the same type.
    712      *
    713      * In either case, back up and search down the remainder of the branch
    714      */
    715     Status = AcpiNsWalkNamespace (ACPI_TYPE_ANY, Node,
    716         ACPI_UINT32_MAX, ACPI_NS_WALK_UNLOCK,
    717         AcpiEvInstallHandler, NULL, HandlerObj, NULL);
    718 
    719 UnlockAndExit:
    720     return_ACPI_STATUS (Status);
    721 }
    722