diff --git a/arch/arm64/boot/dts/st/stm32mp257d-engicam-microgea-rmm-overlay-am-1280800w8tzqw-t00h.dtso b/arch/arm64/boot/dts/st/stm32mp257d-engicam-microgea-rmm-overlay-am-1280800w8tzqw-t00h.dtso
index 7655c1bf56b1..b44e1d3ddb1b 100644
--- a/arch/arm64/boot/dts/st/stm32mp257d-engicam-microgea-rmm-overlay-am-1280800w8tzqw-t00h.dtso
+++ b/arch/arm64/boot/dts/st/stm32mp257d-engicam-microgea-rmm-overlay-am-1280800w8tzqw-t00h.dtso
@@ -32,6 +32,9 @@ &framebuffer {
 };
 
 &ltdc {
+	/* LVDS output: the pixel clock is the LVDS PHY one */
+	assigned-clocks = <&syscfg>;
+	assigned-clock-parents = <&lvds>;
 	status = "okay";
 
 	port {
diff --git a/arch/arm64/boot/dts/st/stm32mp257d-engicam-microgea-rmm-overlay-rk050hr345-ct106a.dtso b/arch/arm64/boot/dts/st/stm32mp257d-engicam-microgea-rmm-overlay-rk050hr345-ct106a.dtso
index 7be955be58ed..7855086c33c7 100644
--- a/arch/arm64/boot/dts/st/stm32mp257d-engicam-microgea-rmm-overlay-rk050hr345-ct106a.dtso
+++ b/arch/arm64/boot/dts/st/stm32mp257d-engicam-microgea-rmm-overlay-rk050hr345-ct106a.dtso
@@ -38,6 +38,8 @@ touchscreen@38 {
 &ltdc {
 	/* RGB output: the pixel clock is the LTDC kernel clock */
 	clocks = <&rcc CK_KER_LTDC>, <&rcc CK_BUS_LTDC>, <&syscfg>, <&lvds>;
+	assigned-clocks = <&syscfg>;
+	assigned-clock-parents = <&rcc CK_KER_LTDC>;
 	pinctrl-names = "default", "sleep";
 	pinctrl-0 = <&ltdc_pins_a>;
 	pinctrl-1 = <&ltdc_sleep_pins_a>;