+/*******************************************************************************
+ *
+ * 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) {
+ *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);
+}
+