ramips: add support for ALFA Network Tube-E4G

ALFA Network Tube-E4G is an outdoor, dual-SIM LTE Cat. 4 CPE, based on
MediaTek MT7620A, equipped with Quectel EC25 miniPCIe modem.

Specification:

- MT7620A (580 MHz)
- 64/128/256 MB of RAM (DDR2)
- 16/32 MB of flash (SPI NOR)
- 1x 10/100 Mbps Ethernet, with passive PoE support (24 V)
- 1x miniPCIe slot (with PCIe and USB 2.0 buses)
- 2x SIM slot (mini, micro) with detect and switch driven by GPIO
- 1x detachable antenna (modem main)
- 1x internal antenna (modem div)
- 1x GPS passive antenna (optional)
- 5x LED (all driven by GPIO)
- 1x button (reset)
- UART (4-pin, 2.54 mm pitch) header on PCB

Other:

Default SIM slot is selected at an early stage by U-Boot, based on
'default_sim' environment value: 1 or unset = SIM1 (mini), 2 = SIM2
(micro). U-Boot also resets the modem, using #PERST signal, before
starting kernel.

Flash instruction:

You can use the 'sysupgrade' image directly in vendor firmware which is
based on OpenWrt (make sure to not preserve settings - use 'sysupgrade
-n -F ...' command). Alternatively, use web recovery mode in U-Boot:

1. Power the device with reset button pressed, the LAN LED will start
   blinking slowly and after ~3 seconds, when it starts blinking faster,
   you can release the button.
2. Setup static IP 192.168.1.2/24 on your PC.
3. Go to 192.168.1.1 in browser and upload 'sysupgrade' image.

Signed-off-by: Piotr Dymacz <pepe2k@gmail.com>

1 files changed, 190 insertions, 0 deletions

diff --git a/target/linux/ramips/dts/TUBE-E4G.dts b/target/linux/ramips/dts/TUBE-E4G.dts
new file mode 100644
index 0000000000..4097dc6140
--- /dev/null
+++ b/target/linux/ramips/dts/TUBE-E4G.dts
@@ -0,0 +1,190 @@
+// SPDX-License-Identifier: GPL-2.0-or-later OR MIT
+/dts-v1/;
+
+#include "mt7620a.dtsi"
+
+#include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/input/input.h>
+
+/ {
+	compatible = "alfa-network,tube-e4g", "ralink,mt7620a-soc";
+	model = "ALFA Network Tube-E4G";
+
+	aliases {
+		led-boot = &power;
+		led-failsafe = &power;
+		led-running = &power;
+		led-upgrade = &power;
+	};
+
+	chosen {
+		bootargs = "console=ttyS0,115200";
+	};
+
+	gpio-export {
+		compatible = "gpio-export";
+		#size-cells = <0>;
+
+		modem-enable {
+			gpio-export,name = "modem-enable";
+			gpio-export,output = <1>;
+			gpios = <&gpio1 12 GPIO_ACTIVE_HIGH>;
+		};
+
+		modem-rf-enable {
+			gpio-export,name = "modem-rf-enable";
+			gpio-export,output = <1>;
+			gpios = <&gpio0 12 GPIO_ACTIVE_HIGH>;
+		};
+
+		sim-select {
+			gpio-export,name = "sim-select";
+			gpio-export,output = <0>;
+			gpios = <&gpio0 13 GPIO_ACTIVE_HIGH>;
+		};
+
+		sim1-detect {
+			gpio-export,name = "sim1-detect";
+			gpios = <&gpio0 9 GPIO_ACTIVE_HIGH>;
+		};
+
+		sim2-detect {
+			gpio-export,name = "sim2-detect";
+			gpios = <&gpio2 1 GPIO_ACTIVE_HIGH>;
+		};
+	};
+
+	keys {
+		compatible = "gpio-keys";
+
+		reset {
+			label = "reset";
+			linux,code = <KEY_RESTART>;
+			gpios = <&gpio2 15 GPIO_ACTIVE_LOW>;
+			debounce-interval = <60>;
+		};
+	};
+
+	leds {
+		compatible = "gpio-leds";
+
+		4g {
+			label = "tube-e4g:green:4g";
+			gpios = <&gpio0 7 GPIO_ACTIVE_LOW>;
+		};
+
+		lan {
+			label = "tube-e4g:blue:lan";
+			gpios = <&gpio2 4 GPIO_ACTIVE_LOW>;
+		};
+
+		power: power {
+			label = "tube-e4g:green:power";
+			gpios = <&gpio2 0 GPIO_ACTIVE_LOW>;
+			default-state = "keep";
+		};
+
+		sim1 {
+			label = "tube-e4g:green:sim1";
+			gpios = <&gpio2 3 GPIO_ACTIVE_LOW>;
+			default-state = "keep";
+		};
+
+		sim2 {
+			label = "tube-e4g:green:sim2";
+			gpios = <&gpio2 2 GPIO_ACTIVE_LOW>;
+			default-state = "keep";
+		};
+	};
+};
+
+&ehci {
+	status = "okay";
+};
+
+&ethernet {
+	mtd-mac-address = <&factory 0x28>;
+};
+
+&gpio0 {
+	status = "okay";
+};
+
+&gpio1 {
+	status = "okay";
+};
+
+&gpio2 {
+	status = "okay";
+};
+
+&gsw {
+	mediatek,port4 = "ephy";
+};
+
+&ohci {
+	status = "okay";
+};
+
+&pcie {
+	status = "disabled";
+};
+
+&pinctrl {
+	state_default: pinctrl0 {
+		gpio {
+			ralink,group = "ephy", "nd_sd", "pcie", "uartf";
+			ralink,function = "gpio";
+		};
+	};
+};
+
+&spi0 {
+	status = "okay";
+
+	flash@0 {
+		compatible = "jedec,spi-nor";
+		reg = <0>;
+		spi-max-frequency = <50000000>;
+		m25p,fast-read;
+
+		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 0x1000>;
+			};
+
+			partition@31000 {
+				label = "config";
+				reg = <0x31000 0xf000>;
+				read-only;
+			};
+
+			factory: partition@40000 {
+				label = "factory";
+				reg = <0x40000 0x10000>;
+				read-only;
+			};
+
+			partition@50000 {
+				compatible = "denx,uimage";
+				label = "firmware";
+				reg = <0x50000 0xfb0000>;
+			};
+		};
+	};
+};
+
+&wmac {
+	status = "disabled";
+};