[ACPI] ACPICA 20060317

[powerpc.git] / drivers / acpi / utilities / utresrc.c

diff --git a/drivers/acpi/utilities/utresrc.c b/drivers/acpi/utilities/utresrc.c
index 27158dd..4c24e6d 100644 (file)
--- a/drivers/acpi/utilities/utresrc.c
+++ b/drivers/acpi/utilities/utresrc.c
@@ -238,6 +238,104 @@ static const u8 acpi_gbl_resource_types[] = {
        ACPI_FIXED_LENGTH
 };
 
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ut_walk_aml_resources
+ *
+ * PARAMETERS:  Aml             - Pointer to the raw AML resource template
+ *              aml_length      - Length of the entire template
+ *              user_function   - Called once for each descriptor found. If
+ *                                NULL, a pointer to the end_tag is returned
+ *              Context         - Passed to user_function
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Walk a raw AML resource list(buffer). User function called
+ *              once for each resource found.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ut_walk_aml_resources(u8 * aml,
+                          acpi_size aml_length,
+                          acpi_walk_aml_callback user_function, void *context)
+{
+       acpi_status status;
+       u8 *end_aml;
+       u8 resource_index;
+       u32 length;
+       u32 offset = 0;
+
+       ACPI_FUNCTION_TRACE("ut_walk_aml_resources");
+
+       /* The absolute minimum resource template is one end_tag descriptor */
+
+       if (aml_length < sizeof(struct aml_resource_end_tag)) {
+               return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
+       }
+
+       /* Point to the end of the resource template buffer */
+
+       end_aml = aml + aml_length;
+
+       /* Walk the byte list, abort on any invalid descriptor type or length */
+
+       while (aml < end_aml) {
+
+               /* Validate the Resource Type and Resource Length */
+
+               status = acpi_ut_validate_resource(aml, &resource_index);
+               if (ACPI_FAILURE(status)) {
+                       return_ACPI_STATUS(status);
+               }
+
+               /* Get the length of this descriptor */
+
+               length = acpi_ut_get_descriptor_length(aml);
+
+               /* Invoke the user function */
+
+               if (user_function) {
+                       status =
+                           user_function(aml, length, offset, resource_index,
+                                         context);
+                       if (ACPI_FAILURE(status)) {
+                               return (status);
+                       }
+               }
+
+               /* An end_tag descriptor terminates this resource template */
+
+               if (acpi_ut_get_resource_type(aml) ==
+                   ACPI_RESOURCE_NAME_END_TAG) {
+                       /*
+                        * There must be at least one more byte in the buffer for
+                        * the 2nd byte of the end_tag
+                        */
+                       if ((aml + 1) >= end_aml) {
+                               return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
+                       }
+
+                       /* Return the pointer to the end_tag if requested */
+
+                       if (!user_function) {
+                               *(void **)context = aml;
+                       }
+
+                       /* Normal exit */
+
+                       return_ACPI_STATUS(AE_OK);
+               }
+
+               aml += length;
+               offset += length;
+       }
+
+       /* Did not find an end_tag descriptor */
+
+       return (AE_AML_NO_RESOURCE_END_TAG);
+}
+
 /*******************************************************************************
  *
  * FUNCTION:    acpi_ut_validate_resource
@@ -498,61 +596,21 @@ acpi_ut_get_resource_end_tag(union acpi_operand_object * obj_desc,
                             u8 ** end_tag)
 {
        acpi_status status;
-       u8 *aml;
-       u8 *end_aml;
 
        ACPI_FUNCTION_TRACE("ut_get_resource_end_tag");
 
-       /* Get start and end pointers */
-
-       aml = obj_desc->buffer.pointer;
-       end_aml = aml + obj_desc->buffer.length;
-
        /* Allow a buffer length of zero */
 
        if (!obj_desc->buffer.length) {
-               *end_tag = aml;
+               *end_tag = obj_desc->buffer.pointer;
                return_ACPI_STATUS(AE_OK);
        }
 
-       /* Walk the resource template, one descriptor per iteration */
-
-       while (aml < end_aml) {
-
-               /* Validate the Resource Type and Resource Length */
-
-               status = acpi_ut_validate_resource(aml, NULL);
-               if (ACPI_FAILURE(status)) {
-                       return_ACPI_STATUS(status);
-               }
-
-               /* end_tag resource indicates the end of the resource template */
-
-               if (acpi_ut_get_resource_type(aml) ==
-                   ACPI_RESOURCE_NAME_END_TAG) {
-                       /*
-                        * There must be at least one more byte in the buffer for
-                        * the 2nd byte of the end_tag
-                        */
-                       if ((aml + 1) >= end_aml) {
-                               return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
-                       }
-
-                       /* Return the pointer to the end_tag */
-
-                       *end_tag = aml;
-                       return_ACPI_STATUS(AE_OK);
-               }
-
-               /*
-                * Point to the next resource descriptor in the AML buffer. The
-                * descriptor length is guaranteed to be non-zero by resource
-                * validation above.
-                */
-               aml += acpi_ut_get_descriptor_length(aml);
-       }
+       /* Validate the template and get a pointer to the end_tag */
 
-       /* Did not find an end_tag resource descriptor */
+       status = acpi_ut_walk_aml_resources(obj_desc->buffer.pointer,
+                                           obj_desc->buffer.length, NULL,
+                                           end_tag);
 
-       return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
+       return_ACPI_STATUS(status);
 }