diff --git a/drivers/acpi/resources/rscalc.c b/drivers/acpi/resources/rscalc.c
index db0a835e331..d801823de01 100644
--- a/drivers/acpi/resources/rscalc.c
+++ b/drivers/acpi/resources/rscalc.c
@@ -213,11 +213,22 @@ acpi_rs_get_aml_length(struct acpi_resource * resource, acpi_size * size_needed)
 		switch (resource->type) {
 		case ACPI_RESOURCE_TYPE_IRQ:
 
+			/* Length can be 3 or 2 */
+
 			if (resource->data.irq.descriptor_length == 2) {
 				total_size--;
 			}
 			break;
 
+		case ACPI_RESOURCE_TYPE_START_DEPENDENT:
+
+			/* Length can be 1 or 0 */
+
+			if (resource->data.irq.descriptor_length == 0) {
+				total_size--;
+			}
+			break;
+
 		case ACPI_RESOURCE_TYPE_VENDOR:
 			/*
 			 * Vendor Defined Resource:
diff --git a/drivers/acpi/resources/rsio.c b/drivers/acpi/resources/rsio.c
index 50f3acdd9c8..610d7c2101f 100644
--- a/drivers/acpi/resources/rsio.c
+++ b/drivers/acpi/resources/rsio.c
@@ -268,7 +268,7 @@ struct acpi_rsconvert_info acpi_rs_set_start_dpf[10] = {
 
 	/* Reset length to 1 byte (descriptor with flags byte) */
 
-	{ACPI_RSC_LENGTH, 0, 0, sizeof(struct aml_resource_irq)},
+	{ACPI_RSC_LENGTH, 0, 0, sizeof(struct aml_resource_start_dependent)},
 
 	/*
 	 * All done if flags byte is necessary -- if either priority value