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rsxface.c revision 1.5
      1 /*******************************************************************************
      2  *
      3  * Module Name: rsxface - Public interfaces to the resource manager
      4  *
      5  ******************************************************************************/
      6 
      7 /*
      8  * Copyright (C) 2000 - 2014, Intel Corp.
      9  * All rights reserved.
     10  *
     11  * Redistribution and use in source and binary forms, with or without
     12  * modification, are permitted provided that the following conditions
     13  * are met:
     14  * 1. Redistributions of source code must retain the above copyright
     15  *    notice, this list of conditions, and the following disclaimer,
     16  *    without modification.
     17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
     18  *    substantially similar to the "NO WARRANTY" disclaimer below
     19  *    ("Disclaimer") and any redistribution must be conditioned upon
     20  *    including a substantially similar Disclaimer requirement for further
     21  *    binary redistribution.
     22  * 3. Neither the names of the above-listed copyright holders nor the names
     23  *    of any contributors may be used to endorse or promote products derived
     24  *    from this software without specific prior written permission.
     25  *
     26  * Alternatively, this software may be distributed under the terms of the
     27  * GNU General Public License ("GPL") version 2 as published by the Free
     28  * Software Foundation.
     29  *
     30  * NO WARRANTY
     31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
     33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
     34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
     35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
     39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
     40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     41  * POSSIBILITY OF SUCH DAMAGES.
     42  */
     43 
     44 #define __RSXFACE_C__
     45 #define EXPORT_ACPI_INTERFACES
     46 
     47 #include "acpi.h"
     48 #include "accommon.h"
     49 #include "acresrc.h"
     50 #include "acnamesp.h"
     51 
     52 #define _COMPONENT          ACPI_RESOURCES
     53         ACPI_MODULE_NAME    ("rsxface")
     54 
     55 /* Local macros for 16,32-bit to 64-bit conversion */
     56 
     57 #define ACPI_COPY_FIELD(Out, In, Field)  ((Out)->Field = (In)->Field)
     58 #define ACPI_COPY_ADDRESS(Out, In)                      \
     59     ACPI_COPY_FIELD(Out, In, ResourceType);              \
     60     ACPI_COPY_FIELD(Out, In, ProducerConsumer);          \
     61     ACPI_COPY_FIELD(Out, In, Decode);                    \
     62     ACPI_COPY_FIELD(Out, In, MinAddressFixed);           \
     63     ACPI_COPY_FIELD(Out, In, MaxAddressFixed);           \
     64     ACPI_COPY_FIELD(Out, In, Info);                      \
     65     ACPI_COPY_FIELD(Out, In, Granularity);               \
     66     ACPI_COPY_FIELD(Out, In, Minimum);                   \
     67     ACPI_COPY_FIELD(Out, In, Maximum);                   \
     68     ACPI_COPY_FIELD(Out, In, TranslationOffset);         \
     69     ACPI_COPY_FIELD(Out, In, AddressLength);             \
     70     ACPI_COPY_FIELD(Out, In, ResourceSource);
     71 
     72 
     73 /* Local prototypes */
     74 
     75 static ACPI_STATUS
     76 AcpiRsMatchVendorResource (
     77     ACPI_RESOURCE           *Resource,
     78     void                    *Context);
     79 
     80 static ACPI_STATUS
     81 AcpiRsValidateParameters (
     82     ACPI_HANDLE             DeviceHandle,
     83     ACPI_BUFFER             *Buffer,
     84     ACPI_NAMESPACE_NODE     **ReturnNode);
     85 
     86 
     87 /*******************************************************************************
     88  *
     89  * FUNCTION:    AcpiRsValidateParameters
     90  *
     91  * PARAMETERS:  DeviceHandle    - Handle to a device
     92  *              Buffer          - Pointer to a data buffer
     93  *              ReturnNode      - Pointer to where the device node is returned
     94  *
     95  * RETURN:      Status
     96  *
     97  * DESCRIPTION: Common parameter validation for resource interfaces
     98  *
     99  ******************************************************************************/
    100 
    101 static ACPI_STATUS
    102 AcpiRsValidateParameters (
    103     ACPI_HANDLE             DeviceHandle,
    104     ACPI_BUFFER             *Buffer,
    105     ACPI_NAMESPACE_NODE     **ReturnNode)
    106 {
    107     ACPI_STATUS             Status;
    108     ACPI_NAMESPACE_NODE     *Node;
    109 
    110 
    111     ACPI_FUNCTION_TRACE (RsValidateParameters);
    112 
    113 
    114     /*
    115      * Must have a valid handle to an ACPI device
    116      */
    117     if (!DeviceHandle)
    118     {
    119         return_ACPI_STATUS (AE_BAD_PARAMETER);
    120     }
    121 
    122     Node = AcpiNsValidateHandle (DeviceHandle);
    123     if (!Node)
    124     {
    125         return_ACPI_STATUS (AE_BAD_PARAMETER);
    126     }
    127 
    128     if (Node->Type != ACPI_TYPE_DEVICE)
    129     {
    130         return_ACPI_STATUS (AE_TYPE);
    131     }
    132 
    133     /*
    134      * Validate the user buffer object
    135      *
    136      * if there is a non-zero buffer length we also need a valid pointer in
    137      * the buffer. If it's a zero buffer length, we'll be returning the
    138      * needed buffer size (later), so keep going.
    139      */
    140     Status = AcpiUtValidateBuffer (Buffer);
    141     if (ACPI_FAILURE (Status))
    142     {
    143         return_ACPI_STATUS (Status);
    144     }
    145 
    146     *ReturnNode = Node;
    147     return_ACPI_STATUS (AE_OK);
    148 }
    149 
    150 
    151 /*******************************************************************************
    152  *
    153  * FUNCTION:    AcpiGetIrqRoutingTable
    154  *
    155  * PARAMETERS:  DeviceHandle    - Handle to the Bus device we are querying
    156  *              RetBuffer       - Pointer to a buffer to receive the
    157  *                                current resources for the device
    158  *
    159  * RETURN:      Status
    160  *
    161  * DESCRIPTION: This function is called to get the IRQ routing table for a
    162  *              specific bus. The caller must first acquire a handle for the
    163  *              desired bus. The routine table is placed in the buffer pointed
    164  *              to by the RetBuffer variable parameter.
    165  *
    166  *              If the function fails an appropriate status will be returned
    167  *              and the value of RetBuffer is undefined.
    168  *
    169  *              This function attempts to execute the _PRT method contained in
    170  *              the object indicated by the passed DeviceHandle.
    171  *
    172  ******************************************************************************/
    173 
    174 ACPI_STATUS
    175 AcpiGetIrqRoutingTable  (
    176     ACPI_HANDLE             DeviceHandle,
    177     ACPI_BUFFER             *RetBuffer)
    178 {
    179     ACPI_STATUS             Status;
    180     ACPI_NAMESPACE_NODE     *Node;
    181 
    182 
    183     ACPI_FUNCTION_TRACE (AcpiGetIrqRoutingTable);
    184 
    185 
    186     /* Validate parameters then dispatch to internal routine */
    187 
    188     Status = AcpiRsValidateParameters (DeviceHandle, RetBuffer, &Node);
    189     if (ACPI_FAILURE (Status))
    190     {
    191         return_ACPI_STATUS (Status);
    192     }
    193 
    194     Status = AcpiRsGetPrtMethodData (Node, RetBuffer);
    195     return_ACPI_STATUS (Status);
    196 }
    197 
    198 ACPI_EXPORT_SYMBOL (AcpiGetIrqRoutingTable)
    199 
    200 
    201 /*******************************************************************************
    202  *
    203  * FUNCTION:    AcpiGetCurrentResources
    204  *
    205  * PARAMETERS:  DeviceHandle    - Handle to the device object for the
    206  *                                device we are querying
    207  *              RetBuffer       - Pointer to a buffer to receive the
    208  *                                current resources for the device
    209  *
    210  * RETURN:      Status
    211  *
    212  * DESCRIPTION: This function is called to get the current resources for a
    213  *              specific device. The caller must first acquire a handle for
    214  *              the desired device. The resource data is placed in the buffer
    215  *              pointed to by the RetBuffer variable parameter.
    216  *
    217  *              If the function fails an appropriate status will be returned
    218  *              and the value of RetBuffer is undefined.
    219  *
    220  *              This function attempts to execute the _CRS method contained in
    221  *              the object indicated by the passed DeviceHandle.
    222  *
    223  ******************************************************************************/
    224 
    225 ACPI_STATUS
    226 AcpiGetCurrentResources (
    227     ACPI_HANDLE             DeviceHandle,
    228     ACPI_BUFFER             *RetBuffer)
    229 {
    230     ACPI_STATUS             Status;
    231     ACPI_NAMESPACE_NODE     *Node;
    232 
    233 
    234     ACPI_FUNCTION_TRACE (AcpiGetCurrentResources);
    235 
    236 
    237     /* Validate parameters then dispatch to internal routine */
    238 
    239     Status = AcpiRsValidateParameters (DeviceHandle, RetBuffer, &Node);
    240     if (ACPI_FAILURE (Status))
    241     {
    242         return_ACPI_STATUS (Status);
    243     }
    244 
    245     Status = AcpiRsGetCrsMethodData (Node, RetBuffer);
    246     return_ACPI_STATUS (Status);
    247 }
    248 
    249 ACPI_EXPORT_SYMBOL (AcpiGetCurrentResources)
    250 
    251 
    252 /*******************************************************************************
    253  *
    254  * FUNCTION:    AcpiGetPossibleResources
    255  *
    256  * PARAMETERS:  DeviceHandle    - Handle to the device object for the
    257  *                                device we are querying
    258  *              RetBuffer       - Pointer to a buffer to receive the
    259  *                                resources for the device
    260  *
    261  * RETURN:      Status
    262  *
    263  * DESCRIPTION: This function is called to get a list of the possible resources
    264  *              for a specific device. The caller must first acquire a handle
    265  *              for the desired device. The resource data is placed in the
    266  *              buffer pointed to by the RetBuffer variable.
    267  *
    268  *              If the function fails an appropriate status will be returned
    269  *              and the value of RetBuffer is undefined.
    270  *
    271  ******************************************************************************/
    272 
    273 ACPI_STATUS
    274 AcpiGetPossibleResources (
    275     ACPI_HANDLE             DeviceHandle,
    276     ACPI_BUFFER             *RetBuffer)
    277 {
    278     ACPI_STATUS             Status;
    279     ACPI_NAMESPACE_NODE     *Node;
    280 
    281 
    282     ACPI_FUNCTION_TRACE (AcpiGetPossibleResources);
    283 
    284 
    285     /* Validate parameters then dispatch to internal routine */
    286 
    287     Status = AcpiRsValidateParameters (DeviceHandle, RetBuffer, &Node);
    288     if (ACPI_FAILURE (Status))
    289     {
    290         return_ACPI_STATUS (Status);
    291     }
    292 
    293     Status = AcpiRsGetPrsMethodData (Node, RetBuffer);
    294     return_ACPI_STATUS (Status);
    295 }
    296 
    297 ACPI_EXPORT_SYMBOL (AcpiGetPossibleResources)
    298 
    299 
    300 /*******************************************************************************
    301  *
    302  * FUNCTION:    AcpiSetCurrentResources
    303  *
    304  * PARAMETERS:  DeviceHandle    - Handle to the device object for the
    305  *                                device we are setting resources
    306  *              InBuffer        - Pointer to a buffer containing the
    307  *                                resources to be set for the device
    308  *
    309  * RETURN:      Status
    310  *
    311  * DESCRIPTION: This function is called to set the current resources for a
    312  *              specific device. The caller must first acquire a handle for
    313  *              the desired device. The resource data is passed to the routine
    314  *              the buffer pointed to by the InBuffer variable.
    315  *
    316  ******************************************************************************/
    317 
    318 ACPI_STATUS
    319 AcpiSetCurrentResources (
    320     ACPI_HANDLE             DeviceHandle,
    321     ACPI_BUFFER             *InBuffer)
    322 {
    323     ACPI_STATUS             Status;
    324     ACPI_NAMESPACE_NODE     *Node;
    325 
    326 
    327     ACPI_FUNCTION_TRACE (AcpiSetCurrentResources);
    328 
    329 
    330     /* Validate the buffer, don't allow zero length */
    331 
    332     if ((!InBuffer) ||
    333         (!InBuffer->Pointer) ||
    334         (!InBuffer->Length))
    335     {
    336         return_ACPI_STATUS (AE_BAD_PARAMETER);
    337     }
    338 
    339     /* Validate parameters then dispatch to internal routine */
    340 
    341     Status = AcpiRsValidateParameters (DeviceHandle, InBuffer, &Node);
    342     if (ACPI_FAILURE (Status))
    343     {
    344         return_ACPI_STATUS (Status);
    345     }
    346 
    347     Status = AcpiRsSetSrsMethodData (Node, InBuffer);
    348     return_ACPI_STATUS (Status);
    349 }
    350 
    351 ACPI_EXPORT_SYMBOL (AcpiSetCurrentResources)
    352 
    353 
    354 /*******************************************************************************
    355  *
    356  * FUNCTION:    AcpiGetEventResources
    357  *
    358  * PARAMETERS:  DeviceHandle    - Handle to the device object for the
    359  *                                device we are getting resources
    360  *              InBuffer        - Pointer to a buffer containing the
    361  *                                resources to be set for the device
    362  *
    363  * RETURN:      Status
    364  *
    365  * DESCRIPTION: This function is called to get the event resources for a
    366  *              specific device. The caller must first acquire a handle for
    367  *              the desired device. The resource data is passed to the routine
    368  *              the buffer pointed to by the InBuffer variable. Uses the
    369  *              _AEI method.
    370  *
    371  ******************************************************************************/
    372 
    373 ACPI_STATUS
    374 AcpiGetEventResources (
    375     ACPI_HANDLE             DeviceHandle,
    376     ACPI_BUFFER             *RetBuffer)
    377 {
    378     ACPI_STATUS             Status;
    379     ACPI_NAMESPACE_NODE     *Node;
    380 
    381 
    382     ACPI_FUNCTION_TRACE (AcpiGetEventResources);
    383 
    384 
    385     /* Validate parameters then dispatch to internal routine */
    386 
    387     Status = AcpiRsValidateParameters (DeviceHandle, RetBuffer, &Node);
    388     if (ACPI_FAILURE (Status))
    389     {
    390         return_ACPI_STATUS (Status);
    391     }
    392 
    393     Status = AcpiRsGetAeiMethodData (Node, RetBuffer);
    394     return_ACPI_STATUS (Status);
    395 }
    396 
    397 ACPI_EXPORT_SYMBOL (AcpiGetEventResources)
    398 
    399 
    400 /******************************************************************************
    401  *
    402  * FUNCTION:    AcpiResourceToAddress64
    403  *
    404  * PARAMETERS:  Resource        - Pointer to a resource
    405  *              Out             - Pointer to the users's return buffer
    406  *                                (a struct acpi_resource_address64)
    407  *
    408  * RETURN:      Status
    409  *
    410  * DESCRIPTION: If the resource is an address16, address32, or address64,
    411  *              copy it to the address64 return buffer. This saves the
    412  *              caller from having to duplicate code for different-sized
    413  *              addresses.
    414  *
    415  ******************************************************************************/
    416 
    417 ACPI_STATUS
    418 AcpiResourceToAddress64 (
    419     ACPI_RESOURCE               *Resource,
    420     ACPI_RESOURCE_ADDRESS64     *Out)
    421 {
    422     ACPI_RESOURCE_ADDRESS16     *Address16;
    423     ACPI_RESOURCE_ADDRESS32     *Address32;
    424 
    425 
    426     if (!Resource || !Out)
    427     {
    428         return (AE_BAD_PARAMETER);
    429     }
    430 
    431     /* Convert 16 or 32 address descriptor to 64 */
    432 
    433     switch (Resource->Type)
    434     {
    435     case ACPI_RESOURCE_TYPE_ADDRESS16:
    436 
    437         Address16 = ACPI_CAST_PTR (ACPI_RESOURCE_ADDRESS16, &Resource->Data);
    438         ACPI_COPY_ADDRESS (Out, Address16);
    439         break;
    440 
    441     case ACPI_RESOURCE_TYPE_ADDRESS32:
    442 
    443         Address32 = ACPI_CAST_PTR (ACPI_RESOURCE_ADDRESS32, &Resource->Data);
    444         ACPI_COPY_ADDRESS (Out, Address32);
    445         break;
    446 
    447     case ACPI_RESOURCE_TYPE_ADDRESS64:
    448 
    449         /* Simple copy for 64 bit source */
    450 
    451         ACPI_MEMCPY (Out, &Resource->Data, sizeof (ACPI_RESOURCE_ADDRESS64));
    452         break;
    453 
    454     default:
    455 
    456         return (AE_BAD_PARAMETER);
    457     }
    458 
    459     return (AE_OK);
    460 }
    461 
    462 ACPI_EXPORT_SYMBOL (AcpiResourceToAddress64)
    463 
    464 
    465 /*******************************************************************************
    466  *
    467  * FUNCTION:    AcpiGetVendorResource
    468  *
    469  * PARAMETERS:  DeviceHandle    - Handle for the parent device object
    470  *              Name            - Method name for the parent resource
    471  *                                (METHOD_NAME__CRS or METHOD_NAME__PRS)
    472  *              Uuid            - Pointer to the UUID to be matched.
    473  *                                includes both subtype and 16-byte UUID
    474  *              RetBuffer       - Where the vendor resource is returned
    475  *
    476  * RETURN:      Status
    477  *
    478  * DESCRIPTION: Walk a resource template for the specified device to find a
    479  *              vendor-defined resource that matches the supplied UUID and
    480  *              UUID subtype. Returns a ACPI_RESOURCE of type Vendor.
    481  *
    482  ******************************************************************************/
    483 
    484 ACPI_STATUS
    485 AcpiGetVendorResource (
    486     ACPI_HANDLE             DeviceHandle,
    487     char                    *Name,
    488     ACPI_VENDOR_UUID        *Uuid,
    489     ACPI_BUFFER             *RetBuffer)
    490 {
    491     ACPI_VENDOR_WALK_INFO   Info;
    492     ACPI_STATUS             Status;
    493 
    494 
    495     /* Other parameters are validated by AcpiWalkResources */
    496 
    497     if (!Uuid || !RetBuffer)
    498     {
    499         return (AE_BAD_PARAMETER);
    500     }
    501 
    502     Info.Uuid = Uuid;
    503     Info.Buffer = RetBuffer;
    504     Info.Status = AE_NOT_EXIST;
    505 
    506     /* Walk the _CRS or _PRS resource list for this device */
    507 
    508     Status = AcpiWalkResources (DeviceHandle, Name, AcpiRsMatchVendorResource,
    509                 &Info);
    510     if (ACPI_FAILURE (Status))
    511     {
    512         return (Status);
    513     }
    514 
    515     return (Info.Status);
    516 }
    517 
    518 ACPI_EXPORT_SYMBOL (AcpiGetVendorResource)
    519 
    520 
    521 /*******************************************************************************
    522  *
    523  * FUNCTION:    AcpiRsMatchVendorResource
    524  *
    525  * PARAMETERS:  ACPI_WALK_RESOURCE_CALLBACK
    526  *
    527  * RETURN:      Status
    528  *
    529  * DESCRIPTION: Match a vendor resource via the ACPI 3.0 UUID
    530  *
    531  ******************************************************************************/
    532 
    533 static ACPI_STATUS
    534 AcpiRsMatchVendorResource (
    535     ACPI_RESOURCE           *Resource,
    536     void                    *Context)
    537 {
    538     ACPI_VENDOR_WALK_INFO       *Info = Context;
    539     ACPI_RESOURCE_VENDOR_TYPED  *Vendor;
    540     ACPI_BUFFER                 *Buffer;
    541     ACPI_STATUS                 Status;
    542 
    543 
    544     /* Ignore all descriptors except Vendor */
    545 
    546     if (Resource->Type != ACPI_RESOURCE_TYPE_VENDOR)
    547     {
    548         return (AE_OK);
    549     }
    550 
    551     Vendor = &Resource->Data.VendorTyped;
    552 
    553     /*
    554      * For a valid match, these conditions must hold:
    555      *
    556      * 1) Length of descriptor data must be at least as long as a UUID struct
    557      * 2) The UUID subtypes must match
    558      * 3) The UUID data must match
    559      */
    560     if ((Vendor->ByteLength < (ACPI_UUID_LENGTH + 1)) ||
    561         (Vendor->UuidSubtype != Info->Uuid->Subtype)  ||
    562         (ACPI_MEMCMP (Vendor->Uuid, Info->Uuid->Data, ACPI_UUID_LENGTH)))
    563     {
    564         return (AE_OK);
    565     }
    566 
    567     /* Validate/Allocate/Clear caller buffer */
    568 
    569     Buffer = Info->Buffer;
    570     Status = AcpiUtInitializeBuffer (Buffer, Resource->Length);
    571     if (ACPI_FAILURE (Status))
    572     {
    573         return (Status);
    574     }
    575 
    576     /* Found the correct resource, copy and return it */
    577 
    578     ACPI_MEMCPY (Buffer->Pointer, Resource, Resource->Length);
    579     Buffer->Length = Resource->Length;
    580 
    581     /* Found the desired descriptor, terminate resource walk */
    582 
    583     Info->Status = AE_OK;
    584     return (AE_CTRL_TERMINATE);
    585 }
    586 
    587 
    588 /*******************************************************************************
    589  *
    590  * FUNCTION:    AcpiWalkResourceBuffer
    591  *
    592  * PARAMETERS:  Buffer          - Formatted buffer returned by one of the
    593  *                                various Get*Resource functions
    594  *              UserFunction    - Called for each resource
    595  *              Context         - Passed to UserFunction
    596  *
    597  * RETURN:      Status
    598  *
    599  * DESCRIPTION: Walks the input resource template. The UserFunction is called
    600  *              once for each resource in the list.
    601  *
    602  ******************************************************************************/
    603 
    604 ACPI_STATUS
    605 AcpiWalkResourceBuffer (
    606     ACPI_BUFFER                 *Buffer,
    607     ACPI_WALK_RESOURCE_CALLBACK UserFunction,
    608     void                        *Context)
    609 {
    610     ACPI_STATUS                 Status = AE_OK;
    611     ACPI_RESOURCE               *Resource;
    612     ACPI_RESOURCE               *ResourceEnd;
    613 
    614     ACPI_FUNCTION_TRACE (AcpiWalkResourceBuffer);
    615 
    616 
    617     /* Parameter validation */
    618 
    619     if (!Buffer || !Buffer->Pointer || !UserFunction)
    620     {
    621         return_ACPI_STATUS (AE_BAD_PARAMETER);
    622     }
    623 
    624     /* Buffer contains the resource list and length */
    625 
    626     Resource = ACPI_CAST_PTR (ACPI_RESOURCE, Buffer->Pointer);
    627     ResourceEnd = ACPI_ADD_PTR (ACPI_RESOURCE, Buffer->Pointer, Buffer->Length);
    628 
    629     /* Walk the resource list until the EndTag is found (or buffer end) */
    630 
    631     while (Resource < ResourceEnd)
    632     {
    633         /* Sanity check the resource type */
    634 
    635         if (Resource->Type > ACPI_RESOURCE_TYPE_MAX)
    636         {
    637             Status = AE_AML_INVALID_RESOURCE_TYPE;
    638             break;
    639         }
    640 
    641         /* Sanity check the length. It must not be zero, or we loop forever */
    642 
    643         if (!Resource->Length)
    644         {
    645             return_ACPI_STATUS (AE_AML_BAD_RESOURCE_LENGTH);
    646         }
    647 
    648         /* Invoke the user function, abort on any error returned */
    649 
    650         Status = UserFunction (Resource, Context);
    651         if (ACPI_FAILURE (Status))
    652         {
    653             if (Status == AE_CTRL_TERMINATE)
    654             {
    655                 /* This is an OK termination by the user function */
    656 
    657                 Status = AE_OK;
    658             }
    659             break;
    660         }
    661 
    662         /* EndTag indicates end-of-list */
    663 
    664         if (Resource->Type == ACPI_RESOURCE_TYPE_END_TAG)
    665         {
    666             break;
    667         }
    668 
    669         /* Get the next resource descriptor */
    670 
    671         Resource = ACPI_NEXT_RESOURCE (Resource);
    672     }
    673 
    674     return_ACPI_STATUS (Status);
    675 }
    676 
    677 ACPI_EXPORT_SYMBOL (AcpiWalkResourceBuffer)
    678 
    679 
    680 /*******************************************************************************
    681  *
    682  * FUNCTION:    AcpiWalkResources
    683  *
    684  * PARAMETERS:  DeviceHandle    - Handle to the device object for the
    685  *                                device we are querying
    686  *              Name            - Method name of the resources we want.
    687  *                                (METHOD_NAME__CRS, METHOD_NAME__PRS, or
    688  *                                METHOD_NAME__AEI)
    689  *              UserFunction    - Called for each resource
    690  *              Context         - Passed to UserFunction
    691  *
    692  * RETURN:      Status
    693  *
    694  * DESCRIPTION: Retrieves the current or possible resource list for the
    695  *              specified device. The UserFunction is called once for
    696  *              each resource in the list.
    697  *
    698  ******************************************************************************/
    699 
    700 ACPI_STATUS
    701 AcpiWalkResources (
    702     ACPI_HANDLE                 DeviceHandle,
    703     const char                  *Name,
    704     ACPI_WALK_RESOURCE_CALLBACK UserFunction,
    705     void                        *Context)
    706 {
    707     ACPI_STATUS                 Status;
    708     ACPI_BUFFER                 Buffer;
    709 
    710 
    711     ACPI_FUNCTION_TRACE (AcpiWalkResources);
    712 
    713 
    714     /* Parameter validation */
    715 
    716     if (!DeviceHandle || !UserFunction || !Name ||
    717         (!ACPI_COMPARE_NAME (Name, METHOD_NAME__CRS) &&
    718          !ACPI_COMPARE_NAME (Name, METHOD_NAME__PRS) &&
    719          !ACPI_COMPARE_NAME (Name, METHOD_NAME__AEI)))
    720     {
    721         return_ACPI_STATUS (AE_BAD_PARAMETER);
    722     }
    723 
    724     /* Get the _CRS/_PRS/_AEI resource list */
    725 
    726     Buffer.Length = ACPI_ALLOCATE_LOCAL_BUFFER;
    727     Status = AcpiRsGetMethodData (DeviceHandle, __UNCONST(Name), &Buffer);
    728     if (ACPI_FAILURE (Status))
    729     {
    730         return_ACPI_STATUS (Status);
    731     }
    732 
    733     /* Walk the resource list and cleanup */
    734 
    735     Status = AcpiWalkResourceBuffer (&Buffer, UserFunction, Context);
    736     ACPI_FREE (Buffer.Pointer);
    737     return_ACPI_STATUS (Status);
    738 }
    739 
    740 ACPI_EXPORT_SYMBOL (AcpiWalkResources)
    741