feat: Integrate VND7050AJ driver and enhance gateway settings

This commit introduces the VND7050AJ driver as a new submodule and integrates it into the project.

Key changes include:
- Added  as a git submodule.
- Enhanced the gateway application () with LittleFS and the settings subsystem.
  - Implemented new shell commands (, , ) for managing custom settings.
  - Added functionality to compact the settings file.
- Updated  to include new library dependencies and log  return code.
- Adjusted include paths for  in relevant files.
Signed-off-by: Eduard Iten <eduard@iten.pro>

software/apps/slave_node/CMakeLists.txt

@@ -3,6 +3,8 @@ cmake_minimum_required(VERSION 3.20)
 find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
 
 project(slave_node LANGUAGES C)
+
 zephyr_include_directories(../../include)
 add_subdirectory(../../lib lib)
+
 target_sources(app PRIVATE src/main.c)

software/apps/slave_node/boards/native_sim.overlay

@@ -0,0 +1,47 @@
+/ {
+	aliases {
+		vnd7050aj = &vnd7050aj;
+	};
+
+	vnd7050aj: vnd7050aj {
+		compatible = "st,vnd7050aj";
+		status = "okay";
+
+		input0-gpios = <&gpio0 1 GPIO_ACTIVE_HIGH>;
+		input1-gpios = <&gpio0 2 GPIO_ACTIVE_HIGH>;
+		select0-gpios = <&gpio0 3 GPIO_ACTIVE_HIGH>;
+		select1-gpios = <&gpio0 4 GPIO_ACTIVE_HIGH>;
+		sense-enable-gpios = <&gpio0 5 GPIO_ACTIVE_HIGH>;
+		fault-reset-gpios = <&gpio0 6 GPIO_ACTIVE_LOW>;
+		io-channels = <&adc0 0>;
+		r-sense-ohms = <1500>;
+		k-vcc = <4000>;
+	};
+
+	modbus_uart: uart_2 {
+		compatible = "zephyr,native-pty-uart";
+		status = "okay";
+		current-speed = <19200>;
+
+		modbus0: modbus0 {
+			compatible = "zephyr,modbus-serial";
+			status = "okay";
+		};
+	};
+
+};
+
+&adc0 {
+	#address-cells = <1>;
+	#size-cells = <0>;
+	ref-internal-mv = <3300>;
+	ref-external1-mv = <5000>;
+
+	channel@0 {
+		reg = <0>;
+		zephyr,gain = "ADC_GAIN_1";
+		zephyr,reference = "ADC_REF_INTERNAL";
+		zephyr,acquisition-time = <ADC_ACQ_TIME_DEFAULT>;
+		zephyr,resolution = <12>;
+	};
+};

software/apps/slave_node/dts/bindings/st,vnd7050aj.yaml

@@ -0,0 +1,88 @@
+# Copyright (c) 2024, Eduard Iten
+# SPDX-License-Identifier: Apache-2.0
+
+description: |
+  STMicroelectronics VND7050AJ dual-channel high-side driver.
+  This is a GPIO and ADC controlled device.
+
+compatible: "st,vnd7050aj"
+
+include: base.yaml
+
+properties:
+  input0-gpios:
+    type: phandle-array
+    required: true
+    description: GPIO to control output channel 0.
+
+  input1-gpios:
+    type: phandle-array
+    required: true
+    description: GPIO to control output channel 1.
+
+  select0-gpios:
+    type: phandle-array
+    required: true
+    description: GPIO for MultiSense selection bit 0.
+
+  select1-gpios:
+    type: phandle-array
+    required: true
+    description: GPIO for MultiSense selection bit 1.
+
+  sense-enable-gpios:
+    type: phandle-array
+    required: true
+    description: GPIO to enable the MultiSense output.
+
+  fault-reset-gpios:
+    type: phandle-array
+    required: true
+    description: GPIO to reset a latched fault (active-low).
+
+  io-channels:
+    type: phandle-array
+    required: true
+    description: |
+      ADC channel connected to the MultiSense pin. This should be an
+      io-channels property pointing to the ADC controller and channel number.
+
+  r-sense-ohms:
+    type: int
+    required: true
+    description: |
+      Value of the external sense resistor connected from the MultiSense
+      pin to GND, specified in Ohms. This is critical for correct
+      conversion of the analog readings.
+
+  k-factor:
+    type: int
+    default: 1500
+    description: |
+      Factor between PowerMOS and SenseMOS.
+
+  k-vcc:
+    type: int
+    default: 8000
+    description: |
+      VCC sense ratio multiplied by 1000. Used for supply voltage calculation.
+
+  t-sense-0:
+    type: int
+    default: 25
+    description: |
+      Temperature sense reference temperature in degrees Celsius.
+
+  v-sense-0:
+    type: int
+    default: 2070
+    description: |
+      Temperature sense reference voltage in millivolts.
+
+  k-tchip:
+    type: int
+    default: -5500
+    description: |
+      Temperature sense gain coefficient multiplied by 1000.
+      Used for chip temperature calculation.
+

software/apps/slave_node/prj.conf

@@ -22,7 +22,7 @@ CONFIG_SETTINGS_LOG_LEVEL_DBG=y
 CONFIG_UART_INTERRUPT_DRIVEN=y
 CONFIG_MODBUS=y
 CONFIG_MODBUS_ROLE_SERVER=y
-CONFIG_MODBUS_BUFFER_SIZE=256
+CONFIG_MODBUS_LOG_LEVEL_DBG=y
 
 # Enable VND7050AJ
 CONFIG_VND7050AJ=y

software/apps/slave_node/src/main.c

@@ -9,6 +9,7 @@ LOG_MODULE_REGISTER(main, LOG_LEVEL_INF);
 
 int main(void)
 {
+	int rc;
 	LOG_INF("Starting Irrigation System Slave Node");
 
 	if (settings_subsys_init() || settings_load()) {
@@ -18,9 +19,10 @@ int main(void)
 	valve_init();
 	fwu_init();
 
-	if (modbus_server_init()) {
-		LOG_ERR("Modbus RTU server initialization failed");
-		return 0;
+	rc = modbus_server_init();
+	if (rc) {
+		LOG_ERR("Modbus server initialization failed: %d", rc);
+		return rc;
 	}
 
 	LOG_INF("Irrigation System Slave Node started successfully");

software/apps/slave_node/sysbuild.conf

@@ -0,0 +1,5 @@
+SB_CONFIG_BOOTLOADER_MCUBOOT=y
+SB_CONFIG_MCUBOOT_MODE_SINGLE_APP=y
+
+CONFIG_LOG=y
+CONFIG_MCUBOOT_LOG_LEVEL_INF=y