diff --git a/Documentation/devicetree/bindings/iio/adc/amlogic,meson-saradc.txt b/Documentation/devicetree/bindings/iio/adc/amlogic,meson-saradc.txt
index 325090e43ce6..75c775954102 100644
--- a/Documentation/devicetree/bindings/iio/adc/amlogic,meson-saradc.txt
+++ b/Documentation/devicetree/bindings/iio/adc/amlogic,meson-saradc.txt
@@ -23,6 +23,10 @@ Required properties:
 - #io-channel-cells: must be 1, see ../iio-bindings.txt
 
 Optional properties:
+- amlogic,hhi-sysctrl:	phandle to the syscon which contains the 5th bit
+			of the TSC (temperature sensor coefficient) on
+			Meson8b and Meson8m2 (which used to calibrate the
+			temperature sensor)
 - nvmem-cells:		phandle to the temperature_calib eFuse cells
 - nvmem-cell-names:	if present (to enable the temperature sensor
 			calibration) this must contain "temperature_calib"