diff --git a/Documentation/devicetree/bindings/interrupt-controller/st,stm32-exti.txt b/Documentation/devicetree/bindings/interrupt-controller/st,stm32-exti.txt
index 6a36bf66d932d42320cfc6b3c998b16488609d61..cd01b2292ec685fdb3ca2b1500fadf50090fb1a0 100644
--- a/Documentation/devicetree/bindings/interrupt-controller/st,stm32-exti.txt
+++ b/Documentation/devicetree/bindings/interrupt-controller/st,stm32-exti.txt
@@ -14,6 +14,10 @@ Required properties:
   (only needed for exti controller with multiple exti under
   same parent interrupt: st,stm32-exti and st,stm32h7-exti)
 
+Optional properties:
+
+- hwlocks: reference to a phandle of a hardware spinlock provider node.
+
 Example:
 
 exti: interrupt-controller@40013c00 {