ramips: add support for D-Link DIR-882 R1

Specifications:
- SoC: MediaTek MT7621AT
- RAM: 128 MB (DDR3)
- Flash: 16 MB (SPI NOR)
- WiFi: MediaTek MT7615N (x2)
- Switch: 1 WAN, 4 LAN (Gigabit)
- Ports: 1 USB 2.0, 1 USB 3.0
- Buttons: Reset, WiFi Toggle, WPS
- LEDs: Power, Internet, WiFi 2.4G WiFi 5G, USB 2.0, USB 3.0

The R1 revision is identical to the A1 revision except
- No Config2 Parition, therefore
- factory partition resized to 64k from 128K
- Firmware partition offset is 0x50000 not 0x60000
- Firmware partitions size increased by 64K
- Firmware partition type is "denx,uimage", not "sge,uimage"
- Padding of image creation "uimage-padhdr 96" removed

Installation:
- Older firmware versions: put the factory image on a USB stick, turn on
the telnet console, and flash using the following cmd
"fw_updater Linux /mnt/usb_X_X/firmware.bin"

- D-Link FailsafeUI:
Power down the router, press and hold the reset button, then
re-plug it. Keep the reset button pressed until the internet LED stops
flashing, then jack into any lan port and manually assign a static IP
address in 192.168.0.0/24 other than 192.168.0.0 (e.g. 192.168.0.2)
and go to http://192.168.0.1
Flash with the factory image.

Signed-off-by: Andrew Pikler <andrew.pikler@gmail.com>

6 files changed, 204 insertions, 147 deletions

diff --git a/target/linux/ramips/dts/mt7621_dlink_dir-882-a1.dts b/target/linux/ramips/dts/mt7621_dlink_dir-882-a1.dts
index bc2c6dfe86..cef0705393 100644
--- a/target/linux/ramips/dts/mt7621_dlink_dir-882-a1.dts
+++ b/target/linux/ramips/dts/mt7621_dlink_dir-882-a1.dts
@@ -1,24 +1,9 @@
 // SPDX-License-Identifier: GPL-2.0-or-later OR MIT
 
 #include "mt7621_dlink_dir-8xx-a1.dtsi"
+#include "mt7621_dlink_dir-882-x1.dtsi"
 
 / {
 	compatible = "dlink,dir-882-a1", "mediatek,mt7621-soc";
 	model = "D-Link DIR-882 A1";
 };
-
-&leds {
-	usb2 {
-		label = "green:usb2";
-		gpios = <&gpio 13 GPIO_ACTIVE_LOW>;
-		trigger-sources = <&ehci_port2>;
-		linux,default-trigger = "usbport";
-	};
-
-	usb3 {
-		label = "green:usb3";
-		gpios = <&gpio 14 GPIO_ACTIVE_LOW>;
-		trigger-sources = <&xhci_ehci_port1>;
-		linux,default-trigger = "usbport";
-	};
-};
diff --git a/target/linux/ramips/dts/mt7621_dlink_dir-882-r1.dts b/target/linux/ramips/dts/mt7621_dlink_dir-882-r1.dts
new file mode 100644
index 0000000000..26b6f34707
--- /dev/null
+++ b/target/linux/ramips/dts/mt7621_dlink_dir-882-r1.dts
@@ -0,0 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0-or-later OR MIT
+
+#include "mt7621_dlink_dir-8xx-r1.dtsi"
+#include "mt7621_dlink_dir-882-x1.dtsi"
+
+/ {
+	compatible = "dlink,dir-882-r1", "mediatek,mt7621-soc";
+	model = "D-Link DIR-882 R1";
+};
diff --git a/target/linux/ramips/dts/mt7621_dlink_dir-882-x1.dtsi b/target/linux/ramips/dts/mt7621_dlink_dir-882-x1.dtsi
new file mode 100644
index 0000000000..cafb1df964
--- /dev/null
+++ b/target/linux/ramips/dts/mt7621_dlink_dir-882-x1.dtsi
@@ -0,0 +1,17 @@
+// SPDX-License-Identifier: GPL-2.0-or-later OR MIT
+
+&leds {
+	usb2 {
+		label = "green:usb2";
+		gpios = <&gpio 13 GPIO_ACTIVE_LOW>;
+		trigger-sources = <&ehci_port2>;
+		linux,default-trigger = "usbport";
+	};
+
+	usb3 {
+		label = "green:usb3";
+		gpios = <&gpio 14 GPIO_ACTIVE_LOW>;
+		trigger-sources = <&xhci_ehci_port1>;
+		linux,default-trigger = "usbport";
+	};
+};
diff --git a/target/linux/ramips/dts/mt7621_dlink_dir-8xx-a1.dtsi b/target/linux/ramips/dts/mt7621_dlink_dir-8xx-a1.dtsi
index e451d6a39f..c43cc49aa1 100644
--- a/target/linux/ramips/dts/mt7621_dlink_dir-8xx-a1.dtsi
+++ b/target/linux/ramips/dts/mt7621_dlink_dir-8xx-a1.dtsi
@@ -1,65 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0-or-later OR MIT
 
-#include "mt7621.dtsi"
-
-#include <dt-bindings/gpio/gpio.h>
-#include <dt-bindings/input/input.h>
-
-/ {
-	aliases {
-		label-mac-device = &gmac0;
-		led-boot = &led_power_orange;
-		led-failsafe = &led_power_green;
-		led-running = &led_power_green;
-		led-upgrade = &led_net_orange;
-	};
-
-	keys {
-		compatible = "gpio-keys";
-
-		reset {
-			label = "reset";
-			gpios = <&gpio 15 GPIO_ACTIVE_LOW>;
-			linux,code = <KEY_RESTART>;
-		};
-
-		wps {
-			label = "wps";
-			gpios = <&gpio 18 GPIO_ACTIVE_LOW>;
-			linux,code = <KEY_WPS_BUTTON>;
-		};
-
-		wifi {
-			label = "wifi";
-			gpios = <&gpio 7 GPIO_ACTIVE_LOW>;
-			linux,code = <KEY_RFKILL>;
-		};
-	};
-
-	leds: leds {
-		compatible = "gpio-leds";
-
-		led_power_orange: power_orange {
-			label = "orange:power";
-			gpios = <&gpio 8 GPIO_ACTIVE_LOW>;
-		};
-
-		led_power_green: power_green {
-			label = "green:power";
-			gpios = <&gpio 16 GPIO_ACTIVE_LOW>;
-		};
-
-		led_net_orange: net_orange {
-			label = "orange:net";
-			gpios = <&gpio 4 GPIO_ACTIVE_LOW>;
-		};
-
-		net_green {
-			label = "green:net";
-			gpios = <&gpio 3 GPIO_ACTIVE_LOW>;
-		};
-	};
-};
+#include "mt7621_dlink_dir-8xx-x1.dtsi"
 
 &spi0 {
 	status = "okay";
@@ -100,74 +41,3 @@
 		};
 	};
 };
-
-&pcie {
-	status = "okay";
-};
-
-&pcie0 {
-	wifi@0,0 {
-		compatible = "mediatek,mt76";
-		reg = <0x0000 0 0 0 0>;
-		mediatek,mtd-eeprom = <&factory 0x0000>;
-		ieee80211-freq-limit = <2400000 2500000>;
-
-		led {
-			led-active-low;
-		};
-	};
-};
-
-&pcie1 {
-	wifi@0,0 {
-		compatible = "mediatek,mt76";
-		reg = <0x0000 0 0 0 0>;
-		mediatek,mtd-eeprom = <&factory 0x8000>;
-		ieee80211-freq-limit = <5000000 6000000>;
-
-		led {
-			led-active-low;
-		};
-	};
-};
-
-&gmac0 {
-	mtd-mac-address = <&factory 0xe000>;
-};
-
-&switch0 {
-	ports {
-		port@0 {
-			status = "okay";
-			label = "lan4";
-		};
-
-		port@1 {
-			status = "okay";
-			label = "lan3";
-		};
-
-		port@2 {
-			status = "okay";
-			label = "lan2";
-		};
-
-		port@3 {
-			status = "okay";
-			label = "lan1";
-		};
-
-		port@4 {
-			status = "okay";
-			label = "wan";
-			mtd-mac-address = <&factory 0xe006>;
-		};
-	};
-};
-
-&state_default {
-	gpio {
-		groups = "i2c", "uart3", "jtag", "wdt";
-		function = "gpio";
-	};
-};
diff --git a/target/linux/ramips/dts/mt7621_dlink_dir-8xx-r1.dtsi b/target/linux/ramips/dts/mt7621_dlink_dir-8xx-r1.dtsi
new file mode 100644
index 0000000000..e93a06d9fe
--- /dev/null
+++ b/target/linux/ramips/dts/mt7621_dlink_dir-8xx-r1.dtsi
@@ -0,0 +1,43 @@
+// SPDX-License-Identifier: GPL-2.0-or-later OR MIT
+
+#include "mt7621_dlink_dir-8xx-x1.dtsi"
+
+&spi0 {
+	status = "okay";
+
+	flash@0 {
+		compatible = "jedec,spi-nor";
+		reg = <0>;
+		spi-max-frequency = <50000000>;
+
+		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>;
+			};
+		};
+	};
+};
diff --git a/target/linux/ramips/dts/mt7621_dlink_dir-8xx-x1.dtsi b/target/linux/ramips/dts/mt7621_dlink_dir-8xx-x1.dtsi
new file mode 100644
index 0000000000..7ab0e8bd5d
--- /dev/null
+++ b/target/linux/ramips/dts/mt7621_dlink_dir-8xx-x1.dtsi
@@ -0,0 +1,133 @@
+// SPDX-License-Identifier: GPL-2.0-or-later OR MIT
+
+#include "mt7621.dtsi"
+
+#include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/input/input.h>
+
+/ {
+	aliases {
+		label-mac-device = &gmac0;
+		led-boot = &led_power_orange;
+		led-failsafe = &led_power_green;
+		led-running = &led_power_green;
+		led-upgrade = &led_net_orange;
+	};
+
+	keys {
+		compatible = "gpio-keys";
+
+		reset {
+			label = "reset";
+			gpios = <&gpio 15 GPIO_ACTIVE_LOW>;
+			linux,code = <KEY_RESTART>;
+		};
+
+		wps {
+			label = "wps";
+			gpios = <&gpio 18 GPIO_ACTIVE_LOW>;
+			linux,code = <KEY_WPS_BUTTON>;
+		};
+
+		wifi {
+			label = "wifi";
+			gpios = <&gpio 7 GPIO_ACTIVE_LOW>;
+			linux,code = <KEY_RFKILL>;
+		};
+	};
+
+	leds: leds {
+		compatible = "gpio-leds";
+
+		led_power_orange: power_orange {
+			label = "orange:power";
+			gpios = <&gpio 8 GPIO_ACTIVE_LOW>;
+		};
+
+		led_power_green: power_green {
+			label = "green:power";
+			gpios = <&gpio 16 GPIO_ACTIVE_LOW>;
+		};
+
+		led_net_orange: net_orange {
+			label = "orange:net";
+			gpios = <&gpio 4 GPIO_ACTIVE_LOW>;
+		};
+
+		net_green {
+			label = "green:net";
+			gpios = <&gpio 3 GPIO_ACTIVE_LOW>;
+		};
+	};
+};
+
+&pcie {
+	status = "okay";
+};
+
+&pcie0 {
+	wifi@0,0 {
+		compatible = "mediatek,mt76";
+		reg = <0x0000 0 0 0 0>;
+		mediatek,mtd-eeprom = <&factory 0x0000>;
+		ieee80211-freq-limit = <2400000 2500000>;
+
+		led {
+			led-active-low;
+		};
+	};
+};
+
+&pcie1 {
+	wifi@0,0 {
+		compatible = "mediatek,mt76";
+		reg = <0x0000 0 0 0 0>;
+		mediatek,mtd-eeprom = <&factory 0x8000>;
+		ieee80211-freq-limit = <5000000 6000000>;
+
+		led {
+			led-active-low;
+		};
+	};
+};
+
+&gmac0 {
+	mtd-mac-address = <&factory 0xe000>;
+};
+
+&switch0 {
+	ports {
+		port@0 {
+			status = "okay";
+			label = "lan4";
+		};
+
+		port@1 {
+			status = "okay";
+			label = "lan3";
+		};
+
+		port@2 {
+			status = "okay";
+			label = "lan2";
+		};
+
+		port@3 {
+			status = "okay";
+			label = "lan1";
+		};
+
+		port@4 {
+			status = "okay";
+			label = "wan";
+			mtd-mac-address = <&factory 0xe006>;
+		};
+	};
+};
+
+&state_default {
+	gpio {
+		groups = "i2c", "uart3", "jtag", "wdt";
+		function = "gpio";
+	};
+};