ACPI 5.0: New interface, acpi_buffer_to_resource

This interface converts an AML buffer to an internal ACPI_RESOURCE.
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

drivers/acpi/acpica/rscreate.c

@@ -49,6 +49,70 @@
 #define _COMPONENT          ACPI_RESOURCES
 ACPI_MODULE_NAME("rscreate")
 
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_buffer_to_resource
+ *
+ * PARAMETERS:  aml_buffer          - Pointer to the resource byte stream
+ *              aml_buffer_length   - Length of the aml_buffer
+ *              resource_ptr        - Where the converted resource is returned
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Convert a raw AML buffer to a resource list
+ *
+ ******************************************************************************/
+acpi_status
+acpi_buffer_to_resource(u8 *aml_buffer,
+			u16 aml_buffer_length,
+			struct acpi_resource **resource_ptr)
+{
+	acpi_status status;
+	acpi_size list_size_needed;
+	void *resource;
+	void *current_resource_ptr;
+
+	/*
+	 * Note: we allow AE_AML_NO_RESOURCE_END_TAG, since an end tag
+	 * is not required here.
+	 */
+
+	/* Get the required length for the converted resource */
+
+	status = acpi_rs_get_list_length(aml_buffer, aml_buffer_length,
+					 &list_size_needed);
+	if (status == AE_AML_NO_RESOURCE_END_TAG) {
+		status = AE_OK;
+	}
+	if (ACPI_FAILURE(status)) {
+		return (status);
+	}
+
+	/* Allocate a buffer for the converted resource */
+
+	resource = ACPI_ALLOCATE_ZEROED(list_size_needed);
+	current_resource_ptr = resource;
+	if (!resource) {
+		return (AE_NO_MEMORY);
+	}
+
+	/* Perform the AML-to-Resource conversion */
+
+	status = acpi_ut_walk_aml_resources(aml_buffer, aml_buffer_length,
+					    acpi_rs_convert_aml_to_resources,
+					    &current_resource_ptr);
+	if (status == AE_AML_NO_RESOURCE_END_TAG) {
+		status = AE_OK;
+	}
+	if (ACPI_FAILURE(status)) {
+		ACPI_FREE(resource);
+	} else {
+		*resource_ptr = resource;
+	}
+
+	return (status);
+}
+
 /*******************************************************************************
  *
  * FUNCTION:    acpi_rs_create_resource_list

include/acpi/acpixf.h

@@ -376,6 +376,11 @@ acpi_status
 acpi_resource_to_address64(struct acpi_resource *resource,
 			   struct acpi_resource_address64 *out);
 
+acpi_status
+acpi_buffer_to_resource(u8 *aml_buffer,
+			u16 aml_buffer_length,
+			struct acpi_resource **resource_ptr);
+
 /*
  * Hardware (ACPI device) interfaces
  */