2 files changed, 261 insertions, 202 deletions

diff --git a/drivers/acpi/resources/rsutils.c b/drivers/acpi/resources/rsutils.c
index 0e493f2fec4d..a9cbee8e8b44 100644
--- a/drivers/acpi/resources/rsutils.c
+++ b/drivers/acpi/resources/rsutils.c
@@ -442,7 +442,7 @@ acpi_rs_set_resource_source(union aml_resource * aml,
  *
  * FUNCTION:    acpi_rs_get_prt_method_data
  *
- * PARAMETERS:  Handle          - Handle to the containing object
+ * PARAMETERS:  Node            - Device node
  *              ret_buffer      - Pointer to a buffer structure for the
  *                                results
  *
@@ -457,7 +457,8 @@ acpi_rs_set_resource_source(union aml_resource * aml,
  ******************************************************************************/
 
 acpi_status
-acpi_rs_get_prt_method_data(acpi_handle handle, struct acpi_buffer * ret_buffer)
+acpi_rs_get_prt_method_data(struct acpi_namespace_node * node,
+                            struct acpi_buffer * ret_buffer)
 {
         union acpi_operand_object *obj_desc;
         acpi_status status;
@@ -468,7 +469,7 @@ acpi_rs_get_prt_method_data(acpi_handle handle, struct acpi_buffer * ret_buffer)
 
         /* Execute the method, no parameters */
 
-        status = acpi_ut_evaluate_object(handle, METHOD_NAME__PRT,
+        status = acpi_ut_evaluate_object(node, METHOD_NAME__PRT,
                                          ACPI_BTYPE_PACKAGE, &obj_desc);
         if (ACPI_FAILURE(status)) {
                 return_ACPI_STATUS(status);
@@ -490,7 +491,7 @@ acpi_rs_get_prt_method_data(acpi_handle handle, struct acpi_buffer * ret_buffer)
  *
  * FUNCTION:    acpi_rs_get_crs_method_data
  *
- * PARAMETERS:  Handle          - Handle to the containing object
+ * PARAMETERS:  Node            - Device node
  *              ret_buffer      - Pointer to a buffer structure for the
  *                                results
  *
@@ -505,7 +506,8 @@ acpi_rs_get_prt_method_data(acpi_handle handle, struct acpi_buffer * ret_buffer)
  ******************************************************************************/
 
 acpi_status
-acpi_rs_get_crs_method_data(acpi_handle handle, struct acpi_buffer *ret_buffer)
+acpi_rs_get_crs_method_data(struct acpi_namespace_node *node,
+                            struct acpi_buffer *ret_buffer)
 {
         union acpi_operand_object *obj_desc;
         acpi_status status;
@@ -516,7 +518,7 @@ acpi_rs_get_crs_method_data(acpi_handle handle, struct acpi_buffer *ret_buffer)
 
         /* Execute the method, no parameters */
 
-        status = acpi_ut_evaluate_object(handle, METHOD_NAME__CRS,
+        status = acpi_ut_evaluate_object(node, METHOD_NAME__CRS,
                                          ACPI_BTYPE_BUFFER, &obj_desc);
         if (ACPI_FAILURE(status)) {
                 return_ACPI_STATUS(status);
@@ -539,7 +541,7 @@ acpi_rs_get_crs_method_data(acpi_handle handle, struct acpi_buffer *ret_buffer)
  *
  * FUNCTION:    acpi_rs_get_prs_method_data
  *
- * PARAMETERS:  Handle          - Handle to the containing object
+ * PARAMETERS:  Node            - Device node
  *              ret_buffer      - Pointer to a buffer structure for the
  *                                results
  *
@@ -555,7 +557,8 @@ acpi_rs_get_crs_method_data(acpi_handle handle, struct acpi_buffer *ret_buffer)
 
 #ifdef ACPI_FUTURE_USAGE
 acpi_status
-acpi_rs_get_prs_method_data(acpi_handle handle, struct acpi_buffer *ret_buffer)
+acpi_rs_get_prs_method_data(struct acpi_namespace_node *node,
+                            struct acpi_buffer *ret_buffer)
 {
         union acpi_operand_object *obj_desc;
         acpi_status status;
@@ -566,7 +569,7 @@ acpi_rs_get_prs_method_data(acpi_handle handle, struct acpi_buffer *ret_buffer)
 
         /* Execute the method, no parameters */
 
-        status = acpi_ut_evaluate_object(handle, METHOD_NAME__PRS,
+        status = acpi_ut_evaluate_object(node, METHOD_NAME__PRS,
                                          ACPI_BTYPE_BUFFER, &obj_desc);
         if (ACPI_FAILURE(status)) {
                 return_ACPI_STATUS(status);
@@ -641,7 +644,7 @@ acpi_rs_get_method_data(acpi_handle handle,
  *
  * FUNCTION:    acpi_rs_set_srs_method_data
  *
- * PARAMETERS:  Handle          - Handle to the containing object
+ * PARAMETERS:  Node            - Device node
  *              in_buffer       - Pointer to a buffer structure of the
  *                                parameter
  *
@@ -653,23 +656,37 @@ acpi_rs_get_method_data(acpi_handle handle,
  *              If the function fails an appropriate status will be returned
  *              and the contents of the callers buffer is undefined.
  *
+ * Note: Parameters guaranteed valid by caller
+ *
  ******************************************************************************/
 
 acpi_status
-acpi_rs_set_srs_method_data(acpi_handle handle, struct acpi_buffer *in_buffer)
+acpi_rs_set_srs_method_data(struct acpi_namespace_node *node,
+                            struct acpi_buffer *in_buffer)
 {
-        struct acpi_parameter_info info;
-        union acpi_operand_object *params[2];
+        struct acpi_evaluate_info *info;
+        union acpi_operand_object *args[2];
         acpi_status status;
         struct acpi_buffer buffer;
 
         ACPI_FUNCTION_TRACE(rs_set_srs_method_data);
 
-        /* Parameters guaranteed valid by caller */
+        /* Allocate and initialize the evaluation information block */
+
+        info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
+        if (!info) {
+                return_ACPI_STATUS(AE_NO_MEMORY);
+        }
+
+        info->prefix_node = node;
+        info->pathname = METHOD_NAME__SRS;
+        info->parameters = args;
+        info->parameter_type = ACPI_PARAM_ARGS;
+        info->flags = ACPI_IGNORE_RETURN_VALUE;
 
         /*
          * The in_buffer parameter will point to a linked list of
-         * resource parameters.  It needs to be formatted into a
+         * resource parameters. It needs to be formatted into a
          * byte stream to be sent in as an input parameter to _SRS
          *
          * Convert the linked list into a byte stream
@@ -677,42 +694,36 @@ acpi_rs_set_srs_method_data(acpi_handle handle, struct acpi_buffer *in_buffer)
         buffer.length = ACPI_ALLOCATE_LOCAL_BUFFER;
         status = acpi_rs_create_aml_resources(in_buffer->pointer, &buffer);
         if (ACPI_FAILURE(status)) {
-                return_ACPI_STATUS(status);
+                goto cleanup;
         }
 
-        /* Init the param object */
+        /* Create and initialize the method parameter object */
 
-        params[0] = acpi_ut_create_internal_object(ACPI_TYPE_BUFFER);
-        if (!params[0]) {
-                acpi_os_free(buffer.pointer);
-                return_ACPI_STATUS(AE_NO_MEMORY);
+        args[0] = acpi_ut_create_internal_object(ACPI_TYPE_BUFFER);
+        if (!args[0]) {
+                /*
+                 * Must free the buffer allocated above (otherwise it is freed
+                 * later)
+                 */
+                ACPI_FREE(buffer.pointer);
+                status = AE_NO_MEMORY;
+                goto cleanup;
         }
 
-        /* Set up the parameter object */
-
-        params[0]->buffer.length = (u32) buffer.length;
-        params[0]->buffer.pointer = buffer.pointer;
-        params[0]->common.flags = AOPOBJ_DATA_VALID;
-        params[1] = NULL;
+        args[0]->buffer.length = (u32) buffer.length;
+        args[0]->buffer.pointer = buffer.pointer;
+        args[0]->common.flags = AOPOBJ_DATA_VALID;
+        args[1] = NULL;
 
-        info.node = handle;
-        info.parameters = params;
-        info.parameter_type = ACPI_PARAM_ARGS;
+        /* Execute the method, no return value is expected */
 
-        /* Execute the method, no return value */
+        status = acpi_ns_evaluate(info);
 
-        status = acpi_ns_evaluate_relative(METHOD_NAME__SRS, &info);
-        if (ACPI_SUCCESS(status)) {
-
-                /* Delete any return object (especially if implicit_return is enabled) */
-
-                if (info.return_object) {
-                        acpi_ut_remove_reference(info.return_object);
-                }
-        }
+        /* Clean up and return the status from acpi_ns_evaluate */
 
-        /* Clean up and return the status from acpi_ns_evaluate_relative */
+        acpi_ut_remove_reference(args[0]);
 
-        acpi_ut_remove_reference(params[0]);
+      cleanup:
+        ACPI_FREE(info);
         return_ACPI_STATUS(status);
 }
diff --git a/drivers/acpi/resources/rsxface.c b/drivers/acpi/resources/rsxface.c
index 8c1628c12cc8..1999e2ab7daa 100644
--- a/drivers/acpi/resources/rsxface.c
+++ b/drivers/acpi/resources/rsxface.c
@@ -43,6 +43,7 @@
 
 #include <acpi/acpi.h>
 #include <acpi/acresrc.h>
+#include <acpi/acnamesp.h>
 
 #define _COMPONENT          ACPI_RESOURCES
 ACPI_MODULE_NAME("rsxface")
@@ -66,19 +67,80 @@ ACPI_MODULE_NAME("rsxface")
 static acpi_status
 acpi_rs_match_vendor_resource(struct acpi_resource *resource, void *context);
 
+static acpi_status
+acpi_rs_validate_parameters(acpi_handle device_handle,
+                            struct acpi_buffer *buffer,
+                            struct acpi_namespace_node **return_node);
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_rs_validate_parameters
+ *
+ * PARAMETERS:  device_handle   - Handle to a device
+ *              Buffer          - Pointer to a data buffer
+ *              return_node     - Pointer to where the device node is returned
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Common parameter validation for resource interfaces
+ *
+ ******************************************************************************/
+
+static acpi_status
+acpi_rs_validate_parameters(acpi_handle device_handle,
+                            struct acpi_buffer *buffer,
+                            struct acpi_namespace_node **return_node)
+{
+        acpi_status status;
+        struct acpi_namespace_node *node;
+
+        ACPI_FUNCTION_TRACE(rs_validate_parameters);
+
+        /*
+         * Must have a valid handle to an ACPI device
+         */
+        if (!device_handle) {
+                return_ACPI_STATUS(AE_BAD_PARAMETER);
+        }
+
+        node = acpi_ns_map_handle_to_node(device_handle);
+        if (!node) {
+                return_ACPI_STATUS(AE_BAD_PARAMETER);
+        }
+
+        if (node->type != ACPI_TYPE_DEVICE) {
+                return_ACPI_STATUS(AE_TYPE);
+        }
+
+        /*
+         * Validate the user buffer object
+         *
+         * if there is a non-zero buffer length we also need a valid pointer in
+         * the buffer. If it's a zero buffer length, we'll be returning the
+         * needed buffer size (later), so keep going.
+         */
+        status = acpi_ut_validate_buffer(buffer);
+        if (ACPI_FAILURE(status)) {
+                return_ACPI_STATUS(status);
+        }
+
+        *return_node = node;
+        return_ACPI_STATUS(AE_OK);
+}
+
 /*******************************************************************************
  *
  * FUNCTION:    acpi_get_irq_routing_table
  *
- * PARAMETERS:  device_handle   - a handle to the Bus device we are querying
- *              ret_buffer      - a pointer to a buffer to receive the
+ * PARAMETERS:  device_handle   - Handle to the Bus device we are querying
+ *              ret_buffer      - Pointer to a buffer to receive the
  *                                current resources for the device
  *
  * RETURN:      Status
  *
  * DESCRIPTION: This function is called to get the IRQ routing table for a
- *              specific bus.  The caller must first acquire a handle for the
- *              desired bus.  The routine table is placed in the buffer pointed
+ *              specific bus. The caller must first acquire a handle for the
+ *              desired bus. The routine table is placed in the buffer pointed
  *              to by the ret_buffer variable parameter.
  *
  *              If the function fails an appropriate status will be returned
@@ -94,25 +156,18 @@ acpi_get_irq_routing_table(acpi_handle device_handle,
                            struct acpi_buffer *ret_buffer)
 {
         acpi_status status;
+        struct acpi_namespace_node *node;
 
         ACPI_FUNCTION_TRACE(acpi_get_irq_routing_table);
 
-        /*
-         * Must have a valid handle and buffer, So we have to have a handle
-         * and a return buffer structure, and if there is a non-zero buffer length
-         * we also need a valid pointer in the buffer. If it's a zero buffer length,
-         * we'll be returning the needed buffer size, so keep going.
-         */
-        if (!device_handle) {
-                return_ACPI_STATUS(AE_BAD_PARAMETER);
-        }
+        /* Validate parameters then dispatch to internal routine */
 
-        status = acpi_ut_validate_buffer(ret_buffer);
+        status = acpi_rs_validate_parameters(device_handle, ret_buffer, &node);
         if (ACPI_FAILURE(status)) {
                 return_ACPI_STATUS(status);
         }
 
-        status = acpi_rs_get_prt_method_data(device_handle, ret_buffer);
+        status = acpi_rs_get_prt_method_data(node, ret_buffer);
         return_ACPI_STATUS(status);
 }
 
@@ -122,16 +177,16 @@ ACPI_EXPORT_SYMBOL(acpi_get_irq_routing_table)
  *
  * FUNCTION:    acpi_get_current_resources
  *
- * PARAMETERS:  device_handle   - a handle to the device object for the
+ * PARAMETERS:  device_handle   - Handle to the device object for the
  *                                device we are querying
- *              ret_buffer      - a pointer to a buffer to receive the
+ *              ret_buffer      - Pointer to a buffer to receive the
  *                                current resources for the device
  *
  * RETURN:      Status
  *
  * DESCRIPTION: This function is called to get the current resources for a
- *              specific device.  The caller must first acquire a handle for
- *              the desired device.  The resource data is placed in the buffer
+ *              specific device. The caller must first acquire a handle for
+ *              the desired device. The resource data is placed in the buffer
  *              pointed to by the ret_buffer variable parameter.
  *
  *              If the function fails an appropriate status will be returned
@@ -146,25 +201,18 @@ acpi_get_current_resources(acpi_handle device_handle,
                            struct acpi_buffer *ret_buffer)
 {
         acpi_status status;
+        struct acpi_namespace_node *node;
 
         ACPI_FUNCTION_TRACE(acpi_get_current_resources);
 
-        /*
-         * Must have a valid handle and buffer, So we have to have a handle
-         * and a return buffer structure, and if there is a non-zero buffer length
-         * we also need a valid pointer in the buffer. If it's a zero buffer length,
-         * we'll be returning the needed buffer size, so keep going.
-         */
-        if (!device_handle) {
-                return_ACPI_STATUS(AE_BAD_PARAMETER);
-        }
+        /* Validate parameters then dispatch to internal routine */
 
-        status = acpi_ut_validate_buffer(ret_buffer);
+        status = acpi_rs_validate_parameters(device_handle, ret_buffer, &node);
         if (ACPI_FAILURE(status)) {
                 return_ACPI_STATUS(status);
         }
 
-        status = acpi_rs_get_crs_method_data(device_handle, ret_buffer);
+        status = acpi_rs_get_crs_method_data(node, ret_buffer);
         return_ACPI_STATUS(status);
 }
 
@@ -175,16 +223,16 @@ ACPI_EXPORT_SYMBOL(acpi_get_current_resources)
  *
  * FUNCTION:    acpi_get_possible_resources
  *
- * PARAMETERS:  device_handle   - a handle to the device object for the
+ * PARAMETERS:  device_handle   - Handle to the device object for the
  *                                device we are querying
- *              ret_buffer      - a pointer to a buffer to receive the
+ *              ret_buffer      - Pointer to a buffer to receive the
  *                                resources for the device
  *
  * RETURN:      Status
  *
  * DESCRIPTION: This function is called to get a list of the possible resources
- *              for a specific device.  The caller must first acquire a handle
- *              for the desired device.  The resource data is placed in the
+ *              for a specific device. The caller must first acquire a handle
+ *              for the desired device. The resource data is placed in the
  *              buffer pointed to by the ret_buffer variable.
  *
  *              If the function fails an appropriate status will be returned
@@ -196,25 +244,18 @@ acpi_get_possible_resources(acpi_handle device_handle,
                             struct acpi_buffer *ret_buffer)
 {
         acpi_status status;
+        struct acpi_namespace_node *node;
 
         ACPI_FUNCTION_TRACE(acpi_get_possible_resources);
 
-        /*
-         * Must have a valid handle and buffer, So we have to have a handle
-         * and a return buffer structure, and if there is a non-zero buffer length
-         * we also need a valid pointer in the buffer. If it's a zero buffer length,
-         * we'll be returning the needed buffer size, so keep going.
-         */
-        if (!device_handle) {
-                return_ACPI_STATUS(AE_BAD_PARAMETER);
-        }
+        /* Validate parameters then dispatch to internal routine */
 
-        status = acpi_ut_validate_buffer(ret_buffer);
+        status = acpi_rs_validate_parameters(device_handle, ret_buffer, &node);
         if (ACPI_FAILURE(status)) {
                 return_ACPI_STATUS(status);
         }
 
-        status = acpi_rs_get_prs_method_data(device_handle, ret_buffer);
+        status = acpi_rs_get_prs_method_data(node, ret_buffer);
         return_ACPI_STATUS(status);
 }
 
@@ -223,113 +264,18 @@ ACPI_EXPORT_SYMBOL(acpi_get_possible_resources)
 
 /*******************************************************************************
  *
- * FUNCTION:    acpi_walk_resources
- *
- * PARAMETERS:  device_handle   - Handle to the device object for the
- *                                device we are querying
- *              Name            - Method name of the resources we want
- *                                (METHOD_NAME__CRS or METHOD_NAME__PRS)
- *              user_function   - Called for each resource
- *              Context         - Passed to user_function
- *
- * RETURN:      Status
- *
- * DESCRIPTION: Retrieves the current or possible resource list for the
- *              specified device.  The user_function is called once for
- *              each resource in the list.
- *
- ******************************************************************************/
-acpi_status
-acpi_walk_resources(acpi_handle device_handle,
-                    char *name,
-                    acpi_walk_resource_callback user_function, void *context)
-{
-        acpi_status status;
-        struct acpi_buffer buffer;
-        struct acpi_resource *resource;
-        struct acpi_resource *resource_end;
-
-        ACPI_FUNCTION_TRACE(acpi_walk_resources);
-
-        /* Parameter validation */
-
-        if (!device_handle || !user_function || !name ||
-            (!ACPI_COMPARE_NAME(name, METHOD_NAME__CRS) &&
-             !ACPI_COMPARE_NAME(name, METHOD_NAME__PRS))) {
-                return_ACPI_STATUS(AE_BAD_PARAMETER);
-        }
-
-        /* Get the _CRS or _PRS resource list */
-
-        buffer.length = ACPI_ALLOCATE_LOCAL_BUFFER;
-        status = acpi_rs_get_method_data(device_handle, name, &buffer);
-        if (ACPI_FAILURE(status)) {
-                return_ACPI_STATUS(status);
-        }
-
-        /* Buffer now contains the resource list */
-
-        resource = ACPI_CAST_PTR(struct acpi_resource, buffer.pointer);
-        resource_end =
-            ACPI_ADD_PTR(struct acpi_resource, buffer.pointer, buffer.length);
-
-        /* Walk the resource list until the end_tag is found (or buffer end) */
-
-        while (resource < resource_end) {
-
-                /* Sanity check the resource */
-
-                if (resource->type > ACPI_RESOURCE_TYPE_MAX) {
-                        status = AE_AML_INVALID_RESOURCE_TYPE;
-                        break;
-                }
-
-                /* Invoke the user function, abort on any error returned */
-
-                status = user_function(resource, context);
-                if (ACPI_FAILURE(status)) {
-                        if (status == AE_CTRL_TERMINATE) {
-
-                                /* This is an OK termination by the user function */
-
-                                status = AE_OK;
-                        }
-                        break;
-                }
-
-                /* end_tag indicates end-of-list */
-
-                if (resource->type == ACPI_RESOURCE_TYPE_END_TAG) {
-                        break;
-                }
-
-                /* Get the next resource descriptor */
-
-                resource =
-                    ACPI_ADD_PTR(struct acpi_resource, resource,
-                                 resource->length);
-        }
-
-        ACPI_FREE(buffer.pointer);
-        return_ACPI_STATUS(status);
-}
-
-ACPI_EXPORT_SYMBOL(acpi_walk_resources)
-
-/*******************************************************************************
- *
  * FUNCTION:    acpi_set_current_resources
  *
- * PARAMETERS:  device_handle   - a handle to the device object for the
- *                                device we are changing the resources of
- *              in_buffer       - a pointer to a buffer containing the
+ * PARAMETERS:  device_handle   - Handle to the device object for the
+ *                                device we are setting resources
+ *              in_buffer       - Pointer to a buffer containing the
  *                                resources to be set for the device
  *
  * RETURN:      Status
  *
  * DESCRIPTION: This function is called to set the current resources for a
- *              specific device.  The caller must first acquire a handle for
- *              the desired device.  The resource data is passed to the routine
+ *              specific device. The caller must first acquire a handle for
+ *              the desired device. The resource data is passed to the routine
  *              the buffer pointed to by the in_buffer variable.
  *
  ******************************************************************************/
@@ -338,17 +284,24 @@ acpi_set_current_resources(acpi_handle device_handle,
                            struct acpi_buffer *in_buffer)
 {
         acpi_status status;
+        struct acpi_namespace_node *node;
 
         ACPI_FUNCTION_TRACE(acpi_set_current_resources);
 
-        /* Must have a valid handle and buffer */
+        /* Validate the buffer, don't allow zero length */
 
-        if ((!device_handle) ||
-            (!in_buffer) || (!in_buffer->pointer) || (!in_buffer->length)) {
+        if ((!in_buffer) || (!in_buffer->pointer) || (!in_buffer->length)) {
                 return_ACPI_STATUS(AE_BAD_PARAMETER);
         }
 
-        status = acpi_rs_set_srs_method_data(device_handle, in_buffer);
+        /* Validate parameters then dispatch to internal routine */
+
+        status = acpi_rs_validate_parameters(device_handle, in_buffer, &node);
+        if (ACPI_FAILURE(status)) {
+                return_ACPI_STATUS(status);
+        }
+
+        status = acpi_rs_set_srs_method_data(node, in_buffer);
         return_ACPI_STATUS(status);
 }
 
@@ -358,15 +311,14 @@ ACPI_EXPORT_SYMBOL(acpi_set_current_resources)
  *
  * FUNCTION:    acpi_resource_to_address64
  *
- * PARAMETERS:  Resource                - Pointer to a resource
- *              Out                     - Pointer to the users's return
- *                                        buffer (a struct
- *                                        struct acpi_resource_address64)
+ * PARAMETERS:  Resource        - Pointer to a resource
+ *              Out             - Pointer to the users's return buffer
+ *                                (a struct acpi_resource_address64)
  *
  * RETURN:      Status
  *
  * DESCRIPTION: If the resource is an address16, address32, or address64,
- *              copy it to the address64 return buffer.  This saves the
+ *              copy it to the address64 return buffer. This saves the
  *              caller from having to duplicate code for different-sized
  *              addresses.
  *
@@ -418,12 +370,12 @@ ACPI_EXPORT_SYMBOL(acpi_resource_to_address64)
  *
  * FUNCTION:    acpi_get_vendor_resource
  *
- * PARAMETERS:  device_handle       - Handle for the parent device object
- *              Name                - Method name for the parent resource
- *                                    (METHOD_NAME__CRS or METHOD_NAME__PRS)
- *              Uuid                - Pointer to the UUID to be matched.
- *                                    includes both subtype and 16-byte UUID
- *              ret_buffer          - Where the vendor resource is returned
+ * PARAMETERS:  device_handle   - Handle for the parent device object
+ *              Name            - Method name for the parent resource
+ *                                (METHOD_NAME__CRS or METHOD_NAME__PRS)
+ *              Uuid            - Pointer to the UUID to be matched.
+ *                                includes both subtype and 16-byte UUID
+ *              ret_buffer      - Where the vendor resource is returned
  *
  * RETURN:      Status
  *
@@ -525,3 +477,99 @@ acpi_rs_match_vendor_resource(struct acpi_resource *resource, void *context)
 }
 
 ACPI_EXPORT_SYMBOL(acpi_rs_match_vendor_resource)
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_walk_resources
+ *
+ * PARAMETERS:  device_handle   - Handle to the device object for the
+ *                                device we are querying
+ *              Name            - Method name of the resources we want
+ *                                (METHOD_NAME__CRS or METHOD_NAME__PRS)
+ *              user_function   - Called for each resource
+ *              Context         - Passed to user_function
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Retrieves the current or possible resource list for the
+ *              specified device. The user_function is called once for
+ *              each resource in the list.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_walk_resources(acpi_handle device_handle,
+                    char *name,
+                    acpi_walk_resource_callback user_function, void *context)
+{
+        acpi_status status;
+        struct acpi_buffer buffer;
+        struct acpi_resource *resource;
+        struct acpi_resource *resource_end;
+
+        ACPI_FUNCTION_TRACE(acpi_walk_resources);
+
+        /* Parameter validation */
+
+        if (!device_handle || !user_function || !name ||
+            (!ACPI_COMPARE_NAME(name, METHOD_NAME__CRS) &&
+             !ACPI_COMPARE_NAME(name, METHOD_NAME__PRS))) {
+                return_ACPI_STATUS(AE_BAD_PARAMETER);
+        }
+
+        /* Get the _CRS or _PRS resource list */
+
+        buffer.length = ACPI_ALLOCATE_LOCAL_BUFFER;
+        status = acpi_rs_get_method_data(device_handle, name, &buffer);
+        if (ACPI_FAILURE(status)) {
+                return_ACPI_STATUS(status);
+        }
+
+        /* Buffer now contains the resource list */
+
+        resource = ACPI_CAST_PTR(struct acpi_resource, buffer.pointer);
+        resource_end =
+            ACPI_ADD_PTR(struct acpi_resource, buffer.pointer, buffer.length);
+
+        /* Walk the resource list until the end_tag is found (or buffer end) */
+
+        while (resource < resource_end) {
+
+                /* Sanity check the resource */
+
+                if (resource->type > ACPI_RESOURCE_TYPE_MAX) {
+                        status = AE_AML_INVALID_RESOURCE_TYPE;
+                        break;
+                }
+
+                /* Invoke the user function, abort on any error returned */
+
+                status = user_function(resource, context);
+                if (ACPI_FAILURE(status)) {
+                        if (status == AE_CTRL_TERMINATE) {
+
+                                /* This is an OK termination by the user function */
+
+                                status = AE_OK;
+                        }
+                        break;
+                }
+
+                /* end_tag indicates end-of-list */
+
+                if (resource->type == ACPI_RESOURCE_TYPE_END_TAG) {
+                        break;
+                }
+
+                /* Get the next resource descriptor */
+
+                resource =
+                    ACPI_ADD_PTR(struct acpi_resource, resource,
+                                 resource->length);
+        }
+
+        ACPI_FREE(buffer.pointer);
+        return_ACPI_STATUS(status);
+}
+
+ACPI_EXPORT_SYMBOL(acpi_walk_resources)