hardware driver separation

src/hardware/driver/i2c_bus.cpp

@@ -0,0 +1,94 @@
+#include "i2c_bus.h"
+#include "Wire.h"
+#include <Arduino.h>
+
+void I2C_Bus::scan(void)
+{
+    uint8_t err, addr;
+    int nDevices = 0;
+    for (addr = 1; addr < 127; addr++) {
+        _port->beginTransmission(addr);
+        err = _port->endTransmission();
+        if (err == 0) {
+            Serial.print("I2C device found at address 0x");
+            if (addr < 16)
+                Serial.print("0");
+            Serial.print(addr, HEX);
+            Serial.println(" !");
+            nDevices++;
+        } else if (err == 4) {
+            Serial.print("Unknow error at address 0x");
+            if (addr < 16)
+                Serial.print("0");
+            Serial.println(addr, HEX);
+        }
+    }
+    if (nDevices == 0)
+        Serial.println("No I2C devices found\n");
+    else
+        Serial.println("done\n");
+}
+
+
+uint16_t I2C_Bus::readBytes(uint8_t addr, uint8_t *data, uint16_t len, uint16_t delay_ms)
+{
+    uint16_t ret = 0;
+    xSemaphoreTakeRecursive(_i2c_mux, portMAX_DELAY);
+    uint8_t cnt = _port->requestFrom(addr, (uint8_t)len, (uint8_t)1);
+    if (!cnt) {
+        ret =  1 << 13;
+    }
+    uint16_t index = 0;
+    while (_port->available()) {
+        if (index > len)return 1 << 14;
+        if (delay_ms)delay(delay_ms);
+        data[index++] = _port->read();
+    }
+    xSemaphoreGiveRecursive(_i2c_mux);
+    return ret;
+}
+
+
+uint16_t I2C_Bus::readBytes(uint8_t addr, uint8_t reg, uint8_t *data, uint16_t len)
+{
+    uint16_t ret = 0;
+    xSemaphoreTakeRecursive(_i2c_mux, portMAX_DELAY);
+    _port->beginTransmission(addr);
+    _port->write(reg);
+    _port->endTransmission(false);
+    uint8_t cnt = _port->requestFrom(addr, (uint8_t)len, (uint8_t)1);
+    if (!cnt) {
+        ret =  1 << 13;
+    }
+    uint16_t index = 0;
+    while (_port->available()) {
+        if (index > len)return 1 << 14;
+        data[index++] = _port->read();
+    }
+    xSemaphoreGiveRecursive(_i2c_mux);
+    return ret;
+}
+
+uint16_t I2C_Bus::writeBytes(uint8_t addr, uint8_t reg, uint8_t *data, uint16_t len)
+{
+    uint16_t ret = 0;
+    xSemaphoreTakeRecursive(_i2c_mux, portMAX_DELAY);
+    _port->beginTransmission(addr);
+    _port->write(reg);
+    for (uint16_t i = 0; i < len; i++) {
+        _port->write(data[i]);
+    }
+    ret =  _port->endTransmission();
+    xSemaphoreGiveRecursive(_i2c_mux);
+    return ret ? 1 << 12 : ret;
+}
+
+bool I2C_Bus::deviceProbe(uint8_t addr)
+{
+    uint16_t ret = 0;
+    xSemaphoreTakeRecursive(_i2c_mux, portMAX_DELAY);
+    _port->beginTransmission(addr);
+    ret = _port->endTransmission();
+    xSemaphoreGiveRecursive(_i2c_mux);
+    return (ret == 0);
+}

src/hardware/driver/i2c_bus.h

@@ -0,0 +1,26 @@
+#ifndef I2C_BUS_H
+    #define I2C_BUS_H
+
+    #include <Wire.h>
+    #include "freertos/FreeRTOS.h"
+    #include "freertos/semphr.h"
+
+    class I2C_Bus {
+    public:
+        I2C_Bus(TwoWire &port = Wire, int sda = 21, int scl = 22)
+        {
+            _port = &port;
+            _port->begin(sda, scl);
+            _i2c_mux = xSemaphoreCreateRecursiveMutex();
+        };
+        void scan();
+        uint16_t readBytes(uint8_t addr, uint8_t *data, uint16_t len, uint16_t delay_ms = 0);
+        uint16_t readBytes(uint8_t addr, uint8_t reg, uint8_t *data, uint16_t len);
+        uint16_t writeBytes(uint8_t addr, uint8_t reg, uint8_t *data, uint16_t len);
+        bool deviceProbe(uint8_t addr);
+    private:
+        TwoWire *_port;
+        SemaphoreHandle_t _i2c_mux = NULL;
+    };
+
+#endif // I2C_BUS_H