diff --git a/Documentation/devicetree/bindings/pinctrl/st,stm32-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/st,stm32-pinctrl.txt
index a0eed99214b5..f9753c416974 100644
--- a/Documentation/devicetree/bindings/pinctrl/st,stm32-pinctrl.txt
+++ b/Documentation/devicetree/bindings/pinctrl/st,stm32-pinctrl.txt
@@ -16,7 +16,9 @@ Required properies:
    gpio-bank node (children).
  - interrupt-parent: phandle of the interrupt parent to which the external
    GPIO interrupts are forwarded to.
- - st,syscfg: phandle of the syscfg node used for IRQ mux selection.
+ - st,syscfg: Should be phandle/offset pair. The phandle to the syscon node
+   which includes IRQ mux selection register, and the offset of the IRQ mux
+   selection register.
  - pins-are-numbered: Specify the subnodes are using numbered pinmux to
    specify pins.