ramips: add support for D-Link DWR-116-A1/2

The DWR-116-A1/2 Wireless Router is based on the MT7620N SoC.

Specification:

  MediaTek MT7620N (580 Mhz)
  32 MB of RAM
  8 MB of FLASH
  802.11bgn radio
  5x 10/100 Mbps Ethernet (1 WAN and 4 LAN)
  2x external, non-detachable antennas
  UART (J1 in A1, JP1 in A2) header on PCB (57600 8n1)
  6x LED (GPIO-controlled), 2x button
  JBOOT bootloader

Known issues:
WAN LED is drived by uartl tx pin. I decide to use this pin as
uartlite tx pin.

Installation:
Apply factory image via http web-gui.

Signed-off-by: Pawel Dembicki <paweldembicki@gmail.com>

target/linux/ramips/dts/DWR-116-A1.dts

@@ -0,0 +1,104 @@
+/dts-v1/;
+
+#include "mt7620n.dtsi"
+
+#include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/input/input.h>
+
+/ {
+	compatible = "dlink,dwr-116-a1", "ralink,mt7620n-soc";
+	model = "D-Link DWR-116 A1/A2";
+
+	gpio-keys-polled {
+		compatible = "gpio-keys-polled";
+		#address-cells = <1>;
+		#size-cells = <0>;
+		poll-interval = <20>;
+
+		wps {
+			label = "wps";
+			gpios = <&gpio0 2 GPIO_ACTIVE_LOW>;
+			linux,code = <KEY_WPS_BUTTON>;
+		};
+
+		reset {
+			label = "reset";
+			gpios = <&gpio0 1 GPIO_ACTIVE_LOW>;
+			linux,code = <KEY_RESTART>;
+		};
+	};
+
+	gpio-leds {
+		compatible = "gpio-leds";
+
+		status {
+			label = "dwr-116-a1:green:status";
+			gpios = <&gpio0 0 GPIO_ACTIVE_HIGH>;
+		};
+
+		wifi {
+			label = "dwr-116-a1:green:wifi";
+			gpios = <&gpio3 0 GPIO_ACTIVE_LOW>;
+		};
+	};
+};
+
+&gpio1 {
+	status = "okay";
+};
+
+&gpio3 {
+	status = "okay";
+};
+
+&spi0 {
+	status = "okay";
+
+	m25p80@0 {
+		#address-cells = <1>;
+		#size-cells = <1>;
+		compatible = "jedec,spi-nor";
+		reg = <0>;
+		spi-max-frequency = <50000000>;
+
+		partition@0 {
+			label = "jboot";
+			reg = <0x0 0x10000>;
+			read-only;
+		};
+
+		partition@10000 {
+			label = "firmware";
+			reg = <0x10000 0x7e0000>;
+		};
+
+		config: partition@7f0000 {
+			label = "config";
+			reg = <0x7f0000 0x10000>;
+			read-only;
+		};
+	};
+};
+
+&ehci {
+	status = "okay";
+};
+
+&ohci {
+	status = "okay";
+};
+
+&pinctrl {
+	state_default: pinctrl0 {
+		default {
+			ralink,group = "i2c", "wled";
+			ralink,function = "gpio";
+		};
+	};
+};
+
+&ethernet {
+	mediatek,portmap = "llllw";
+	pinctrl-names = "default";
+	pinctrl-0 = <&ephy_pins>;
+};