ramips: add support for Edimax RA21S

Edimax RA21S is a dual band 11ac router,
based on MediaTek MT7621A and MT7615N chips.

Specification:
- SoC: MediaTek MT7621A dual-core @ 880MHz
- RAM: 256M (Nanya NT5CC128M16IP)
- FLASH: 16MB (Macronix MX25L12835F)
- WiFi: 2.4/5 GHz 4T4R
  - 2.4GHz MediaTek MT7615N bgn
  - 5GHz MediaTek MT7615N nac
- Switch: SoC integrated Gigabit Switch (4 x LAN, 1 x WAN)
- USB: No
- BTN: Reset, WPS
- LED: 4 red LEDs, indistinguishable when case closed
- UART:  through-hole on PCB.
   J1: 3.3V - RX - GND - TX / 57600-8N1.  3.3V is the square pad

Installation:
Update the factory image via the OEM web-interface
(by default: http://192.168.2.1/)
User: admin
Password: 1234

The sysupgrade image can be installed via TFTP
from the U-Boot bootloader. Connect via ethernet port 2.

Tested on device by @UAb5eSMn

Signed-off-by: Maksym Medvedev <redrathnure@gmail.com>
[split DTS and take over improvements from RG21S, extend commit
message]
Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>

target/linux/ramips/dts/mt7621_edimax_ra21s.dts

@@ -0,0 +1,40 @@
+// SPDX-License-Identifier: GPL-2.0-or-later OR MIT
+/dts-v1/;
+
+#include "mt7621_edimax_rx21s.dtsi"
+
+/ {
+	compatible = "edimax,ra21s", "mediatek,mt7621-soc";
+	model = "Edimax RA21S";
+
+	aliases {
+		led-boot = &led_power;
+		led-failsafe = &led_power;
+		led-running = &led_power;
+		led-upgrade = &led_power;
+	};
+
+	leds {
+		compatible = "gpio-leds";
+
+		led_power: led_1 {
+			label = "ra21s:red:led1";
+			gpios = <&gpio0 7 GPIO_ACTIVE_HIGH>;
+		};
+
+		led_2 {
+			label = "ra21s:red:led2";
+			gpios = <&gpio0 12 GPIO_ACTIVE_HIGH>;
+		};
+
+		led_3 {
+			label = "ra21s:red:led3";
+			gpios = <&gpio0 14 GPIO_ACTIVE_HIGH>;
+		};
+
+		led_4 {
+			label = "ra21s:red:led4";
+			gpios = <&gpio0 15 GPIO_ACTIVE_HIGH>;
+		};
+	};
+};

target/linux/ramips/dts/mt7621_edimax_rg21s.dts

@@ -1,10 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0-or-later OR MIT
 /dts-v1/;
 
-#include "mt7621.dtsi"
+#include "mt7621_edimax_rx21s.dtsi"
-
-#include <dt-bindings/gpio/gpio.h>
-#include <dt-bindings/input/input.h>
 
 / {
 	compatible = "edimax,rg21s", "mediatek,mt7621-soc";
@@ -15,27 +12,6 @@
 		led-failsafe = &led_power;
 		led-running = &led_power;
 		led-upgrade = &led_power;
-		label-mac-device = &ethernet;
-	};
-
-	chosen {
-		bootargs = "console=ttyS0,57600";
-	};
-
-	keys {
-		compatible = "gpio-keys";
-
-		reset {
-			label = "reset";
-			gpios = <&gpio0 16 GPIO_ACTIVE_LOW>;
-			linux,code = <KEY_RESTART>;
-		};
-
-		wps {
-			label = "wps";
-			gpios = <&gpio0 18 GPIO_ACTIVE_LOW>;
-			linux,code = <KEY_WPS_BUTTON>;
-		};
 	};
 
 	leds {
@@ -62,85 +38,3 @@
 		};
 	};
 };
-
-&spi0 {
-	status = "okay";
-
-	flash@0 {
-		compatible = "jedec,spi-nor";
-		reg = <0>;
-		spi-max-frequency = <40000000>;
-
-		partitions {
-			compatible = "fixed-partitions";
-			#address-cells = <1>;
-			#size-cells = <1>;
-
-			partition@0 {
-				label = "u-boot";
-				reg = <0x0 0x30000>;
-				read-only;
-			};
-
-			partition@30000 {
-				label = "u-boot-env";
-				reg = <0x30000 0x10000>;
-				read-only;
-			};
-
-			factory: partition@40000 {
-				label = "factory";
-				reg = <0x40000 0x10000>;
-				read-only;
-			};
-
-			partition@50000 {
-				compatible = "denx,uimage";
-				label = "firmware";
-				reg = <0x50000 0xfb0000>;
-			};
-		};
-	};
-};
-
-&pcie {
-	status = "okay";
-};
-
-&pcie0 {
-	wifi0: wifi@0,0 {
-		compatible = "mediatek,mt76";
-		reg = <0x0000 0 0 0 0>;
-		mediatek,mtd-eeprom = <&factory 0x0000>;
-		ieee80211-freq-limit = <2400000 2500000>;
-	};
-};
-
-&pcie1 {
-	wifi1: wifi@0,0 {
-		compatible = "mediatek,mt76";
-		reg = <0x0000 0 0 0 0>;
-		mediatek,mtd-eeprom = <&factory 0x8000>;
-		ieee80211-freq-limit = <5000000 6000000>;
-	};
-};
-
-&ethernet {
-	mtd-mac-address = <&factory 0x4>;
-
-	mediatek,portmap = "wllll";
-	port@5 {
-		status = "disabled";
-	};
-};
-
-&state_default {
-	gpio {
-		ralink,group = "uart3", "uart2", "jtag", "wdt";
-		ralink,function = "gpio";
-	};
-};
-
-&xhci {
-	status = "disabled";
-};

target/linux/ramips/dts/mt7621_edimax_rx21s.dtsi

@@ -0,0 +1,115 @@
+// SPDX-License-Identifier: GPL-2.0-or-later OR MIT
+/dts-v1/;
+
+#include "mt7621.dtsi"
+
+#include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/input/input.h>
+
+/ {
+	aliases {
+		label-mac-device = &ethernet;
+	};
+
+	chosen {
+		bootargs = "console=ttyS0,57600";
+	};
+
+	keys {
+		compatible = "gpio-keys";
+
+		reset {
+			label = "reset";
+			gpios = <&gpio0 16 GPIO_ACTIVE_LOW>;
+			linux,code = <KEY_RESTART>;
+		};
+
+		wps {
+			label = "wps";
+			gpios = <&gpio0 18 GPIO_ACTIVE_LOW>;
+			linux,code = <KEY_WPS_BUTTON>;
+		};
+	};
+};
+
+&spi0 {
+	status = "okay";
+
+	flash@0 {
+		compatible = "jedec,spi-nor";
+		reg = <0>;
+		spi-max-frequency = <40000000>;
+
+		partitions {
+			compatible = "fixed-partitions";
+			#address-cells = <1>;
+			#size-cells = <1>;
+
+			partition@0 {
+				label = "u-boot";
+				reg = <0x0 0x30000>;
+				read-only;
+			};
+
+			partition@30000 {
+				label = "u-boot-env";
+				reg = <0x30000 0x10000>;
+				read-only;
+			};
+
+			factory: partition@40000 {
+				label = "factory";
+				reg = <0x40000 0x10000>;
+				read-only;
+			};
+
+			partition@50000 {
+				compatible = "denx,uimage";
+				label = "firmware";
+				reg = <0x50000 0xfb0000>;
+			};
+		};
+	};
+};
+
+&pcie {
+	status = "okay";
+};
+
+&pcie0 {
+	wifi0: wifi@0,0 {
+		compatible = "mediatek,mt76";
+		reg = <0x0000 0 0 0 0>;
+		mediatek,mtd-eeprom = <&factory 0x0000>;
+		ieee80211-freq-limit = <2400000 2500000>;
+	};
+};
+
+&pcie1 {
+	wifi1: wifi@0,0 {
+		compatible = "mediatek,mt76";
+		reg = <0x0000 0 0 0 0>;
+		mediatek,mtd-eeprom = <&factory 0x8000>;
+		ieee80211-freq-limit = <5000000 6000000>;
+	};
+};
+
+&ethernet {
+	mtd-mac-address = <&factory 0x4>;
+
+	mediatek,portmap = "wllll";
+	port@5 {
+		status = "disabled";
+	};
+};
+
+&state_default {
+	gpio {
+		ralink,group = "uart3", "uart2", "jtag", "wdt";
+		ralink,function = "gpio";
+	};
+};
+
+&xhci {
+	status = "disabled";
+};

target/linux/ramips/image/mt7621.mk

@@ -224,6 +224,20 @@ define Device/d-team_pbr-m1
 endef
 TARGET_DEVICES += d-team_pbr-m1
 
+define Device/edimax_ra21s
+  SOC := mt7621
+  IMAGE_SIZE := 16064k
+  DEVICE_VENDOR := Edimax
+  DEVICE_MODEL := RA21S
+  DEVICE_ALT0_VENDOR := Edimax
+  DEVICE_ALT0_MODEL := Gemini RA21S
+  IMAGES += factory.bin
+  IMAGE/factory.bin := $$(sysupgrade_bin) | check-size $$$$(IMAGE_SIZE) | \
+	elx-header 02020040 8844A2D168B45A2D
+  DEVICE_PACKAGES := kmod-mt7615e wpad-basic
+endef
+TARGET_DEVICES += edimax_ra21s
+
 define Device/edimax_rg21s
   SOC := mt7621
   IMAGE_SIZE := 16064k

target/linux/ramips/mt7621/base-files/etc/board.d/02_network

@@ -87,6 +87,7 @@ ramips_setup_interfaces()
 		ucidef_add_switch "switch0" \
 			"0:lan:4" "1:lan:3" "2:lan:2" "3:lan:1" "4:wan:5" "6@eth0"
 		;;
+	edimax,ra21s|\
 	edimax,rg21s)
 		ucidef_add_switch "switch0" \
 			"1:lan:4" "2:lan:3" "3:lan:2" "4:lan:1" "0:wan" "6@eth0"
@@ -198,6 +199,7 @@ ramips_setup_macs()
 		wan_mac=$(mtd_get_mac_ascii factory wanmac)
 		label_mac=$(mtd_get_mac_binary radio 0x4)
 		;;
+	edimax,ra21s|\
 	edimax,rg21s)
 		lan_mac=$(mtd_get_mac_ascii u-boot-env ethaddr)
 		wan_mac=$(mtd_get_mac_ascii u-boot-env wanaddr)