ARM: dts: sun7i: Add backlight node to Wexler TAB7200 tablet

Add a backlight for controlling the lcd panel backlight on Wexler TAB7200 tablet
Signed-off-by: Aleksei Mamlin <mamlinav@gmail.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>

arch/arm/boot/dts/sun7i-a20-wexler-tab7200.dts

@@ -48,6 +48,7 @@
 #include <dt-bindings/gpio/gpio.h>
 #include <dt-bindings/input/input.h>
 #include <dt-bindings/interrupt-controller/irq.h>
+#include <dt-bindings/pwm/pwm.h>
 
 / {
 	model = "Wexler TAB7200";
@@ -57,6 +58,16 @@ aliases {
 		serial0 = &uart0;
 	};
 
+	backlight {
+		compatible = "pwm-backlight";
+		pwms = <&pwm 0 50000 PWM_POLARITY_INVERTED>;
+		brightness-levels = <0 10 20 30 40 50 60 70 80 90 100>;
+		default-brightness-level = <8>;
+		pinctrl-names = "default";
+		pinctrl-0 = <&bl_enable_pin>;
+		enable-gpios = <&pio 7 7 GPIO_ACTIVE_HIGH>; /* PH7 */
+	};
+
 	chosen {
 		stdout-path = "serial0:115200n8";
 	};
@@ -158,6 +169,13 @@ &otg_sram {
 };
 
 &pio {
+	bl_enable_pin: bl_enable_pin@0 {
+		allwinner,pins = "PH7";
+		allwinner,function = "gpio_out";
+		allwinner,drive = <SUN4I_PINCTRL_10_MA>;
+		allwinner,pull = <SUN4I_PINCTRL_NO_PULL>;
+	};
+
 	ts_reset_pin: ts_reset_pin@0 {
 		allwinner,pins = "PB13";
 		allwinner,function = "gpio_out";