arm: dts: imx8mm_evk: add pwm1/backlight support

Add pwm1/backlight support nodes for imx8mm_evk board

Signed-off-by: Tommaso Merciai <tommaso.merciai@amarulasolutions.com>
diff --git a/arch/arm/dts/imx8mm-evk.dtsi b/arch/arm/dts/imx8mm-evk.dtsi
index 60179e0..e7a2bd8 100644
--- a/arch/arm/dts/imx8mm-evk.dtsi
+++ b/arch/arm/dts/imx8mm-evk.dtsi
@@ -41,6 +41,15 @@
 		enable-active-high;
 	};
 
+	backlight: backlight {
+		status = "disabled";
+		compatible = "pwm-backlight";
+		pwms = <&pwm1 0 5000000>;
+		brightness-levels = <0 255>;
+		num-interpolated-steps = <255>;
+		default-brightness-level = <250>;
+	};
+
 	ir-receiver {
 		compatible = "gpio-ir-receiver";
 		gpios = <&gpio1 13 GPIO_ACTIVE_LOW>;
@@ -350,6 +359,12 @@
 	status = "okay";
 };
 
+&pwm1 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_backlight>;
+	status = "disabled";
+};
+
 &iomuxc {
 	pinctrl_fec1: fec1grp {
 		fsl,pins = <
@@ -491,4 +506,10 @@
 			MX8MM_IOMUXC_GPIO1_IO02_WDOG1_WDOG_B	0x166
 		>;
 	};
+
+	pinctrl_backlight: backlightgrp {
+		fsl,pins = <
+			MX8MM_IOMUXC_GPIO1_IO01_PWM1_OUT	0x06
+		>;
+	};
 };