ARM: dts: cm-t335: add support for PWM backlight

Add pinmux configuration for ECAP0 pin.
Add node for PWM backlight device.
Use PWM output from ecap0 as backlight source.
Signed-off-by: Ilya Ledvich <ilya@compulab.co.il>
Signed-off-by: Uri Mashiach <uri.mashiach@compulab.co.il>
Acked-by: Igor Grinberg <grinberg@compulab.co.il>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/boot/dts/am335x-cm-t335.dts

@@ -39,6 +39,13 @@ vmmc_fixed: fixedregulator@0 {
 		regulator-min-microvolt = <3300000>;
 		regulator-max-microvolt = <3300000>;
 	};
+
+	backlight {
+		compatible = "pwm-backlight";
+		pwms = <&ecap0 0 50000 0>;
+		brightness-levels = <0 51 53 56 62 75 101 152 255>;
+		default-brightness-level = <8>;
+	};
 };
 
 &am33xx_pinmux {
@@ -114,6 +121,13 @@ AM33XX_IOPAD(0x974, PIN_OUTPUT_PULLDOWN | MUX_MODE0)
 		>;
 	};
 
+	ecap0_pins: pinmux_ecap0_pins {
+		pinctrl-single,pins = <
+			/* eCAP0_in_PWM0_out.eCAP0_in_PWM0_out MODE0 */
+			AM33XX_IOPAD(0x964, 0x0)
+		>;
+	};
+
 	cpsw_default: cpsw_default {
 		pinctrl-single,pins = <
 			/* Slave 1 */
@@ -223,6 +237,16 @@ ext_rtc: em3027@56 {
 	};
 };
 
+&epwmss0 {
+	status = "okay";
+
+	ecap0: ecap@48300100 {
+		status = "okay";
+		pinctrl-names = "default";
+		pinctrl-0 = <&ecap0_pins>;
+	};
+};
+
 &gpmc {
 	status = "okay";
 	pinctrl-names = "default";