diff --git a/target/linux/ramips/dts/mt7621_sercomm_na502s.dts b/target/linux/ramips/dts/mt7621_sercomm_na502s.dts
new file mode 100644
index 00000000000000..dc71dbd050297a
--- /dev/null
+++ b/target/linux/ramips/dts/mt7621_sercomm_na502s.dts
@@ -0,0 +1,362 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+#include "mt7621.dtsi"
+
+#include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/input/input.h>
+
+/ {
+	compatible = "sercomm,na502s", "mediatek,mt7621-soc";
+	model = "SERCOMM NA502S";
+
+	aliases {
+		led-boot = &led_power;
+		led-failsafe = &led_power;
+		led-running = &led_power;
+		led-upgrade = &led_power;
+	};
+
+	leds {
+		compatible = "gpio-leds";
+
+		led_power: power {
+			label = "green:power";
+			gpios = <&gpio 0 GPIO_ACTIVE_LOW>;
+		};
+
+		wifi {
+			label = "green:wifi";
+			gpios = <&gpio_expander1 0 GPIO_ACTIVE_LOW>;
+			linux,default-trigger = "phy0tpt";
+		};
+
+		zwave {
+			label = "green:zwave";
+			gpios = <&gpio_expander1 1 GPIO_ACTIVE_LOW>;
+		};
+
+		zigbee {
+			label = "green:zigbee";
+			gpios = <&gpio_expander1 2 GPIO_ACTIVE_LOW>;
+		};
+
+		bluetooth {
+			label = "green:bluetooth";
+			gpios = <&gpio_expander1 3 GPIO_ACTIVE_LOW>;
+		};
+
+		rf433 {
+			label = "green:rf433";
+			gpios = <&gpio_expander1 4 GPIO_ACTIVE_LOW>;
+		};
+
+		service {
+			label = "green:service";
+			gpios = <&gpio_expander1 5 GPIO_ACTIVE_LOW>;
+		};
+
+		3g {
+			label = "green:3g";
+			gpios = <&gpio_expander1 6 GPIO_ACTIVE_LOW>;
+		};
+
+		voice {
+			label = "green:voice";
+			gpios = <&gpio_expander1 7 GPIO_ACTIVE_LOW>;
+		};
+	};
+
+	keys {
+		compatible = "gpio-keys";
+
+		battery_tamper {
+			label = "battery_tamper";
+			gpios = <&gpio 16 GPIO_ACTIVE_HIGH>;
+			linux,code = <BTN_1>;
+		};
+
+		reset {
+			label = "reset";
+			gpios = <&gpio 28 GPIO_ACTIVE_LOW>;
+			linux,code = <KEY_RESTART>;
+		};
+
+		voice {
+			label = "voice";
+			gpios = <&gpio 29 GPIO_ACTIVE_LOW>;
+			linux,code = <BTN_0>;
+		};
+
+		select {
+			label = "select";
+			gpios = <&gpio 31 GPIO_ACTIVE_LOW>;
+			linux,code = <BTN_1>;
+		};
+
+		sync {
+			label = "sync";
+			gpios = <&gpio 32 GPIO_ACTIVE_LOW>;
+			linux,code = <KEY_RFKILL>;
+		};
+	};
+
+	gpio-export {
+		compatible = "gpio-export";
+
+		zwave_reset {
+			gpio-export,name = "zwave_reset";
+			gpio-export,output = <1>;
+			gpios = <&gpio 13 GPIO_ACTIVE_LOW>;
+		};
+
+		lprf_reset {
+			gpio-export,name = "lprf_reset";
+			gpio-export,output = <1>;
+			gpios = <&gpio 14 GPIO_ACTIVE_LOW>;
+		};
+
+		charger_detect {
+			gpio-export,name = "charger_detect";
+			gpios = <&gpio 15 GPIO_ACTIVE_HIGH>;
+		};
+
+		buzzer {
+			gpio-export,name = "buzzer";
+			gpio-export,output = <0>;
+			gpios = <&gpio 17 GPIO_ACTIVE_HIGH>;
+		};
+
+		3g_hw_shunt_en {
+			gpio-export,name = "3g_hw_shunt_en";
+			gpio-export,output = <0>;
+			gpios = <&gpio 22 GPIO_ACTIVE_LOW>;
+		};
+
+		3g_sw_on_off {
+			gpio-export,name = "3g_sw_on_off";
+			gpio-export,output = <1>;
+			gpios = <&gpio 23 GPIO_ACTIVE_LOW>;
+		};
+
+		3g_wake_up {
+			gpio-export,name = "3g_wake_up";
+			gpio-export,output = <0>;
+			gpios = <&gpio 30 GPIO_ACTIVE_LOW>;
+		};
+
+		3g_hw_reset {
+			gpio-export,name = "3g_hw_reset";
+			gpio-export,output = <1>;
+			gpios = <&gpio 33 GPIO_ACTIVE_LOW>;
+		};
+
+		zigbee_reset {
+			gpio-export,name = "zigbee_reset";
+			gpio-export,output = <1>;
+			gpios = <&gpio_expander0 0 GPIO_ACTIVE_LOW>;
+		};
+
+		zigbee_boot {
+			gpio-export,name = "zigbee_boot";
+			gpio-export,output = <1>;
+			gpios = <&gpio_expander0 1 GPIO_ACTIVE_LOW>;
+		};
+
+		2g_sw0 {
+			gpio-export,name = "2g_sw0";
+			gpio-export,output = <1>;
+			gpios = <&gpio_expander0 2 GPIO_ACTIVE_LOW>;
+		};
+
+		2g_sw1 {
+			gpio-export,name = "2g_sw1";
+			gpio-export,output = <1>;
+			gpios = <&gpio_expander0 3 GPIO_ACTIVE_LOW>;
+		};
+
+		fm2018_pwd {
+			gpio-export,name = "fm2018_pwd";
+			gpio-export,output = <1>;
+			gpios = <&gpio_expander0 4 GPIO_ACTIVE_LOW>;
+		};
+
+		fm2018_reset {
+			gpio-export,name = "fm2018_reset";
+			gpio-export,output = <1>;
+			gpios = <&gpio_expander0 5 GPIO_ACTIVE_LOW>;
+		};
+
+		batt_teset {
+			gpio-export,name = "batt_test";
+			gpio-export,output = <1>;
+			gpios = <&gpio_expander0 6 GPIO_ACTIVE_LOW>;
+		};
+
+		mfi_reset {
+			gpio-export,name = "mfi_reset";
+			gpio-export,output = <1>;
+			gpios = <&gpio_expander0 7 GPIO_ACTIVE_LOW>;
+		};
+	};
+};
+
+&ethernet {
+	pinctrl-0 = <&mdio_pins>, <&rgmii1_pins>;
+};
+
+&gmac0 {
+	nvmem-cells = <&macaddr_factory_e000>;
+	nvmem-cell-names = "mac-address";
+};
+
+&nand {
+	status = "okay";
+
+	partitions {
+		compatible = "fixed-partitions";
+		#address-cells = <1>;
+		#size-cells = <1>;
+
+		partition@0 {
+			label = "u-boot";
+			reg = <0x0 0x80000>;
+			read-only;
+		};
+
+		partition@80000 {
+			label = "config";
+			reg = <0x80000 0x80000>;
+			read-only;
+		};
+
+		factory: partition@100000 {
+			label = "factory";
+			reg = <0x100000 0x40000>;
+		};
+
+		partition@140000 {
+			label = "kernel1";
+			reg = <0x140000 0x1400000>;
+		};
+
+		partition@1540000 {
+			label = "kernel";
+			reg = <0x1540000 0x400000>;
+		};
+
+		partition@1940000 {
+			label = "ubi";
+			reg = <0x1940000 0x1000000>;
+		};
+
+		partition@2940000 {
+			label = "user_storage";
+			reg = <0x2940000 0x100000>;
+		};
+
+		partition@2a40000 {
+			label = "data";
+			reg = <0x2a40000 0x1000000>;
+		};
+
+		partition@3a40000 {
+			label = "storage";
+			reg = <0x3a40000 0x3200000>;
+		};
+
+		partition@6c40000 {
+			label = "backup";
+			reg = <0x6c40000 0x1340000>;
+		};
+	};
+};
+
+&pcie {
+	status = "okay";
+};
+
+&pcie0 {
+	wifi@0,0 {
+		compatible = "mediatek,mt76";
+		reg = <0x0000 0 0 0 0>;
+		mediatek,mtd-eeprom = <&factory 0x8000>;
+		nvmem-cells = <&macaddr_factory_e000>;
+		nvmem-cell-names = "mac-address";
+		mac-address-increment = <1>;
+		ieee80211-freq-limit = <5000000 6000000>;
+	};
+};
+
+&pcie1 {
+	wifi@0,0 {
+		compatible = "mediatek,mt76";
+		reg = <0x0 0 0 0 0>;
+		mediatek,mtd-eeprom = <&factory 0x0000>;
+		nvmem-cells = <&macaddr_factory_e000>;
+		nvmem-cell-names = "mac-address";
+		mac-address-increment = <2>;
+		ieee80211-freq-limit = <2400000 2500000>;
+	};
+};
+
+&state_default {
+	gpio {
+		groups = "jtag", "rgmii2";
+		function = "gpio";
+	};
+};
+
+&i2c {
+	status = "okay";
+
+	/* This GPIO expander is fake. The kernel fails to initialize the
+	   first expander, but succeeds on the second (real) one */
+	gpio_expander2: gpio-expander2@22 {
+		#gpio-cells = <2>;
+		#interrupt-cells = <2>;
+		compatible = "semtech,sx1502q";
+		reg = <0x22>;
+
+		gpio-controller;
+	};
+
+	gpio_expander0: gpio-expander0@20 {
+		#gpio-cells = <2>;
+		#interrupt-cells = <2>;
+		compatible = "semtech,sx1502q";
+		reg = <0x20>;
+
+		gpio-controller;
+	};
+
+	gpio_expander1: gpio-expander1@21 {
+		#gpio-cells = <2>;
+		#interrupt-cells = <2>;
+		compatible = "semtech,sx1502q";
+		reg = <0x21>;
+
+		gpio-controller;
+	};
+};
+
+&switch0 {
+	ports {
+		port@4 {
+			status = "okay";
+			label = "lan";
+		};
+	};
+};
+
+&uartlite2 {
+	status = "okay";
+};
+
+&factory {
+	compatible = "nvmem-cells";
+	#address-cells = <1>;
+	#size-cells = <1>;
+
+	macaddr_factory_e000: macaddr@e000 {
+		reg = <0xe000 0x6>;
+	};
+};
diff --git a/target/linux/ramips/image/mt7621.mk b/target/linux/ramips/image/mt7621.mk
index 6a9531aa8ce5f2..a485a5043a0a6b 100644
--- a/target/linux/ramips/image/mt7621.mk
+++ b/target/linux/ramips/image/mt7621.mk
@@ -1485,6 +1485,21 @@ define Device/sercomm_na502
 endef
 TARGET_DEVICES += sercomm_na502
 
+define Device/sercomm_na502s
+  $(Device/uimage-lzma-loader)
+  BLOCKSIZE := 128k
+  PAGESIZE := 2048
+  IMAGE_SIZE := 20971520
+  IMAGE/sysupgrade.bin := sysupgrade-tar | append-metadata
+  UBINIZE_OPTS := -E 5
+  KERNEL_SIZE := 4096k
+  DEVICE_VENDOR := SERCOMM
+  DEVICE_MODEL := NA502S
+  DEVICE_PACKAGES := kmod-mt76x2 kmod-mt7603 kmod-usb3 kmod-usb-serial \
+  		kmod-usb-serial-xr_usb_serial_common
+endef
+TARGET_DEVICES += sercomm_na502s
+
 define Device/storylink_sap-g3200u3
   $(Device/dsa-migration)
   IMAGE_SIZE := 7872k
diff --git a/target/linux/ramips/mt7621/base-files/etc/board.d/02_network b/target/linux/ramips/mt7621/base-files/etc/board.d/02_network
index 688c39940d6e5f..a8d8b8eef2b099 100644
--- a/target/linux/ramips/mt7621/base-files/etc/board.d/02_network
+++ b/target/linux/ramips/mt7621/base-files/etc/board.d/02_network
@@ -13,6 +13,7 @@ ramips_setup_interfaces()
 	mikrotik,routerboard-m11g|\
 	netgear,ex6150|\
 	sercomm,na502|\
+	sercomm,na502s|\
 	thunder,timecloud|\
 	tplink,re350-v1|\
 	tplink,re500-v1|\
diff --git a/target/linux/ramips/mt7621/base-files/lib/upgrade/platform.sh b/target/linux/ramips/mt7621/base-files/lib/upgrade/platform.sh
index c818c7e7cce479..407611a6a2097d 100755
--- a/target/linux/ramips/mt7621/base-files/lib/upgrade/platform.sh
+++ b/target/linux/ramips/mt7621/base-files/lib/upgrade/platform.sh
@@ -84,6 +84,7 @@ platform_do_upgrade() {
 	netis,wf2881|\
 	raisecom,msg1500-x-00|\
 	sercomm,na502|\
+	sercomm,na502s|\
 	xiaomi,mi-router-3g|\
 	xiaomi,mi-router-3-pro|\
 	xiaomi,mi-router-4|\