irrigation_system/software/lib/adc_sensor/adc_sensor.c

307 lines
8.3 KiB
C

/**
* @file adc_sensor.c
* @brief Implementation of the ADC sensor library.
*
* This file contains the implementation for initializing and reading from ADC
* sensors. It currently provides simulated values for voltage and current, with
* placeholders for real hardware ADC implementation including GPIO control.
*/
#include <lib/adc_sensor.h>
#include <zephyr/devicetree.h>
#include <zephyr/drivers/adc.h>
#include <zephyr/drivers/gpio.h>
#include <zephyr/kernel.h>
#include <zephyr/logging/log.h>
LOG_MODULE_REGISTER(adc_sensor, LOG_LEVEL_INF);
// Simulated values
#define SIMULATED_VOLTAGE_MV 12000
#define SIMULATED_CURRENT_MA 45
// Devicetree node checks
#define VOLTAGE_SENSOR_NODE DT_NODELABEL(supply_voltage)
#define CURRENT_SENSOR_NODE DT_NODELABEL(motor_current)
#define SENSOR_MUX_NODE DT_NODELABEL(vnd7050aj_mux)
#ifndef CONFIG_ADC_SENSOR_SIMULATED
// ADC device reference from centralized mux node
#if DT_NODE_EXISTS(SENSOR_MUX_NODE)
#define ADC_NODE DT_PHANDLE(SENSOR_MUX_NODE, io_channels)
#define ADC_CHANNEL DT_PHA(SENSOR_MUX_NODE, io_channels, input)
#define ADC_RESOLUTION 12
#define ADC_REFERENCE_MV DT_PROP(SENSOR_MUX_NODE, reference_mv)
// Sensor-specific properties
#if DT_NODE_EXISTS(VOLTAGE_SENSOR_NODE)
#define VOLTAGE_DIVIDER_RATIO \
DT_PROP(VOLTAGE_SENSOR_NODE, voltage_divider_ratio)
#define VOLTAGE_MUX_CHANNEL DT_PROP(VOLTAGE_SENSOR_NODE, mux_channel)
#define VOLTAGE_DELAY_MS DT_PROP(VOLTAGE_SENSOR_NODE, measurement_delay_ms)
#endif
#if DT_NODE_EXISTS(CURRENT_SENSOR_NODE)
#define CURRENT_SENSE_RESISTOR_MOHM \
DT_PROP(CURRENT_SENSOR_NODE, current_sense_resistor_mohm)
#define CURRENT_MUX_CHANNEL DT_PROP(CURRENT_SENSOR_NODE, mux_channel)
#define CURRENT_DELAY_MS DT_PROP(CURRENT_SENSOR_NODE, measurement_delay_ms)
#endif
static const struct device *adc_dev;
static struct adc_channel_cfg adc_channel_cfg = {
.gain = ADC_GAIN_1,
.reference = ADC_REF_INTERNAL,
.acquisition_time = ADC_ACQ_TIME_DEFAULT,
.channel_id = ADC_CHANNEL,
.differential = 0};
static struct adc_sequence adc_sequence = {
.channels = BIT(ADC_CHANNEL),
.buffer_size = sizeof(uint16_t),
.resolution = ADC_RESOLUTION,
};
static uint16_t adc_buffer;
#endif
#endif
static bool initialized = false;
#ifndef CONFIG_ADC_SENSOR_SIMULATED
// GPIO specs from centralized mux node
#if DT_NODE_EXISTS(SENSOR_MUX_NODE)
static const struct gpio_dt_spec sen_gpio =
GPIO_DT_SPEC_GET(SENSOR_MUX_NODE, sen_gpios);
static const struct gpio_dt_spec s0_gpio =
GPIO_DT_SPEC_GET(SENSOR_MUX_NODE, s0_gpios);
static const struct gpio_dt_spec s1_gpio =
GPIO_DT_SPEC_GET(SENSOR_MUX_NODE, s1_gpios);
#endif
/**
* @brief Configure GPIO pins for ADC sensor multiplexer control
*/
static int configure_sensor_gpios(void) {
int ret = 0;
#if DT_NODE_EXISTS(SENSOR_MUX_NODE)
// Configure sensor multiplexer GPIOs
if (gpio_is_ready_dt(&sen_gpio)) {
ret = gpio_pin_configure_dt(&sen_gpio, GPIO_OUTPUT_INACTIVE);
if (ret < 0) {
LOG_ERR("Failed to configure SEN GPIO: %d", ret);
return ret;
}
}
if (gpio_is_ready_dt(&s0_gpio)) {
ret = gpio_pin_configure_dt(&s0_gpio, GPIO_OUTPUT_INACTIVE);
if (ret < 0) {
LOG_ERR("Failed to configure S0 GPIO: %d", ret);
return ret;
}
}
if (gpio_is_ready_dt(&s1_gpio)) {
ret = gpio_pin_configure_dt(&s1_gpio, GPIO_OUTPUT_INACTIVE);
if (ret < 0) {
LOG_ERR("Failed to configure S1 GPIO: %d", ret);
return ret;
}
}
#endif
return 0;
}
/**
* @brief Set multiplexer channel for sensor selection
* @param enable Enable/disable the sensor
* @param channel Multiplexer channel (0-3)
* @param delay_ms Delay after setting GPIOs
*/
static int set_mux_channel(bool enable, uint8_t channel, uint32_t delay_ms) {
#if DT_NODE_EXISTS(SENSOR_MUX_NODE)
if (gpio_is_ready_dt(&sen_gpio)) {
gpio_pin_set_dt(&sen_gpio, enable ? 1 : 0);
}
if (gpio_is_ready_dt(&s0_gpio)) {
gpio_pin_set_dt(&s0_gpio, (channel & 0x01) ? 1 : 0);
}
if (gpio_is_ready_dt(&s1_gpio)) {
gpio_pin_set_dt(&s1_gpio, (channel & 0x02) ? 1 : 0);
}
// Delay for GPIO settling
if (delay_ms > 0) {
k_msleep(delay_ms);
}
#endif
return 0;
}
#endif /* !CONFIG_ADC_SENSOR_SIMULATED */
#ifndef CONFIG_ADC_SENSOR_SIMULATED
/**
* @brief Read ADC value and convert to millivolts (for voltage sensor)
* @return ADC reading in millivolts, or 0 on error
*/
static uint16_t read_adc_voltage_mv(void) {
#if DT_NODE_EXISTS(SENSOR_MUX_NODE) && DT_NODE_EXISTS(VOLTAGE_SENSOR_NODE)
int ret = adc_read(adc_dev, &adc_sequence);
if (ret < 0) {
LOG_ERR("ADC read failed: %d", ret);
return 0;
}
// Convert ADC reading to millivolts
// ADC reading is 12-bit (0-4095) representing 0 to ADC_REFERENCE_MV
uint32_t adc_value = adc_buffer;
uint32_t voltage_mv = (adc_value * ADC_REFERENCE_MV) / 4095;
// Apply voltage divider scaling
voltage_mv *= VOLTAGE_DIVIDER_RATIO;
LOG_DBG("ADC raw: %u, voltage: %u mV", adc_value, (uint16_t)voltage_mv);
return (uint16_t)voltage_mv;
#else
return 0;
#endif
}
/**
* @brief Read ADC value and convert to milliamps (for current sensor)
* @return ADC reading in milliamps, or 0 on error
*/
static uint16_t read_adc_current_ma(void) {
#if DT_NODE_EXISTS(SENSOR_MUX_NODE) && DT_NODE_EXISTS(CURRENT_SENSOR_NODE)
int ret = adc_read(adc_dev, &adc_sequence);
if (ret < 0) {
LOG_ERR("ADC read failed: %d", ret);
return 0;
}
// Convert ADC reading to millivolts first
uint32_t adc_value = adc_buffer;
uint32_t voltage_mv = (adc_value * ADC_REFERENCE_MV) / 4095;
// Convert voltage to current based on sense resistor
// I = V / R, where R is in milliohms and V is in millivolts
// Result is in milliamps
uint32_t current_ma = (voltage_mv * 1000) / CURRENT_SENSE_RESISTOR_MOHM;
LOG_DBG("ADC raw: %u, current: %u mA", adc_value, (uint16_t)current_ma);
return (uint16_t)current_ma;
#else
return 0;
#endif
}
#endif
int adc_sensor_init(void) {
if (initialized) {
return 0;
}
#ifdef CONFIG_ADC_SENSOR_SIMULATED
LOG_INF("ADC sensor initialized (simulated mode)");
LOG_INF("Simulated values: %dmV, %dmA", SIMULATED_VOLTAGE_MV,
SIMULATED_CURRENT_MA);
#else
// Initialize GPIO pins for sensor control
int ret = configure_sensor_gpios();
if (ret < 0) {
LOG_ERR("Failed to configure sensor GPIOs: %d", ret);
return ret;
}
// Initialize ADC hardware
#if DT_NODE_EXISTS(SENSOR_MUX_NODE)
adc_dev = DEVICE_DT_GET(ADC_NODE);
if (!device_is_ready(adc_dev)) {
LOG_ERR("ADC device not ready");
return -ENODEV;
}
adc_sequence.buffer = &adc_buffer;
ret = adc_channel_setup(adc_dev, &adc_channel_cfg);
if (ret < 0) {
LOG_ERR("Failed to setup ADC channel: %d", ret);
return ret;
}
LOG_INF("ADC device ready: %s", adc_dev->name);
#endif
LOG_INF("ADC sensor initialized (real ADC mode with centralized mux)");
#if DT_NODE_EXISTS(VOLTAGE_SENSOR_NODE)
LOG_INF("Voltage sensor: channel %d, divider ratio %d", VOLTAGE_MUX_CHANNEL,
VOLTAGE_DIVIDER_RATIO);
#endif
#if DT_NODE_EXISTS(CURRENT_SENSOR_NODE)
LOG_INF("Current sensor: channel %d, sense resistor %d mOhm",
CURRENT_MUX_CHANNEL, CURRENT_SENSE_RESISTOR_MOHM);
#endif
#endif
initialized = true;
return 0;
}
uint16_t adc_sensor_get_voltage_mv(void) {
if (!initialized) {
LOG_WRN("ADC sensor not initialized, calling adc_sensor_init()");
adc_sensor_init();
}
#ifdef CONFIG_ADC_SENSOR_SIMULATED
return SIMULATED_VOLTAGE_MV;
#else
// Set multiplexer to voltage channel
#if DT_NODE_EXISTS(VOLTAGE_SENSOR_NODE)
set_mux_channel(true, VOLTAGE_MUX_CHANNEL, VOLTAGE_DELAY_MS);
// Read real ADC value for voltage
uint16_t voltage = read_adc_voltage_mv();
// Disable sensor after measurement to save power
set_mux_channel(false, 0, 0);
return voltage;
#else
return 0;
#endif
#endif
}
uint16_t adc_sensor_get_current_ma(void) {
if (!initialized) {
LOG_WRN("ADC sensor not initialized, calling adc_sensor_init()");
adc_sensor_init();
}
#ifdef CONFIG_ADC_SENSOR_SIMULATED
return SIMULATED_CURRENT_MA;
#else
// Set multiplexer to current channel
#if DT_NODE_EXISTS(CURRENT_SENSOR_NODE)
set_mux_channel(true, CURRENT_MUX_CHANNEL, CURRENT_DELAY_MS);
// Read real ADC value for current
uint16_t current = read_adc_current_ma();
// Disable sensor after measurement to save power
set_mux_channel(false, 0, 0);
return current;
#else
return 0;
#endif
#endif
}