diff --git a/drivers/acpi/resources/rscalc.c b/drivers/acpi/resources/rscalc.c
index 7d6481d..4038dbf 100644
--- a/drivers/acpi/resources/rscalc.c
+++ b/drivers/acpi/resources/rscalc.c
@@ -391,8 +391,7 @@
 			 * Ensure a 32-bit boundary for the structure
 			 */
 			extra_struct_bytes =
-			    ACPI_ROUND_UP_to_32_bITS(resource_length) -
-			    resource_length;
+			    ACPI_ROUND_UP_to_32_bITS(resource_length);
 			break;
 
 		case ACPI_RESOURCE_NAME_END_TAG:
@@ -408,8 +407,7 @@
 			 * Add vendor data and ensure a 32-bit boundary for the structure
 			 */
 			extra_struct_bytes =
-			    ACPI_ROUND_UP_to_32_bITS(resource_length) -
-			    resource_length;
+			    ACPI_ROUND_UP_to_32_bITS(resource_length);
 			break;
 
 		case ACPI_RESOURCE_NAME_ADDRESS32: