Create common interface for different IMU drivers

IMU.h

@@ -0,0 +1,57 @@
+#pragma once
+
+#include "Arduino.h"
+#include "Wire.h"
+#include "SPI.h"
+
+// IMU driver interface
+
+class IMUInterface {
+public:
+	enum IMUType {
+		UNKNOWN,
+		MPU9250,
+		MPU9252,
+		MPU6500,
+		ICM20948,
+	};
+	enum DlpfBandwidth : int8_t {
+		DLPF_BANDWIDTH_184HZ = 0x01,
+		DLPF_BANDWIDTH_92HZ = 0x02,
+		DLPF_BANDWIDTH_41HZ = 0x03,
+		DLPF_BANDWIDTH_20HZ = 0x04,
+		DLPF_BANDWIDTH_10HZ = 0x05,
+		DLPF_BANDWIDTH_5HZ = 0x06
+	};
+	enum AccelRange : int8_t {
+		ACCEL_RANGE_2G = 0x00,
+		ACCEL_RANGE_4G = 0x08,
+		ACCEL_RANGE_8G = 0x10,
+		ACCEL_RANGE_16G = 0x18
+	};
+	enum GyroRange : int8_t {
+		GYRO_RANGE_250DPS = 0x00,
+		GYRO_RANGE_500DPS = 0x08,
+		GYRO_RANGE_1000DPS = 0x10,
+		GYRO_RANGE_2000DPS = 0x18
+	};
+	enum Rate {
+		RATE_MIN,
+		RATE_50HZ_APPROX,
+		RATE_1KHZ_APPROX,
+		RATE_8KHZ_APPROX,
+		RATE_MAX
+	};
+
+	virtual bool begin() = 0;
+	virtual void reset() = 0;
+	virtual uint8_t whoAmI() const = 0;
+	virtual bool read() = 0;
+	virtual void waitForData() = 0;
+	virtual void getAccel(float& x, float& y, float& z) const = 0;
+	virtual void getGyro(float& x, float& y, float& z) const = 0;
+	virtual void getMag(float& x, float& y, float& z) const = 0;
+	virtual float getTemp() const = 0;
+	virtual bool setRate(Rate rate) = 0;
+	virtual const char* getModel() const = 0;
+};

MPU9250.cpp

@@ -471,7 +471,12 @@ void MPU9250::getMag(float& x, float& y, float& z) const {
   y = mag_[1];
   z = mag_[2];
 }
-const char* MPU9250::getType() const {
+bool MPU9250::setRate(Rate rate) {
+  // TODO:
+  log("Rate setting is not implemented");
+  return false;
+}
+const char* MPU9250::getModel() const {
   switch (who_am_i_) {
     case WHOAMI_MPU6500_: return "MPU-6500";
     case WHOAMI_MPU9250_: return "MPU-9250";

MPU9250.h

@@ -35,10 +35,11 @@
 #include <cstdint>
 #include "core/core.h"
 #endif
+#include "IMU.h"
 #include "invensense_imu.h"  // NOLINT
 #include "logger.h"
 
-class MPU9250 : public Logger {
+class MPU9250 : public IMUInterface, public Logger {
  public:
   /* Sensor and filter settings */
   enum I2cAddr : uint8_t {
@@ -53,18 +54,6 @@ class MPU9250 : public Logger {
     DLPF_BANDWIDTH_10HZ = 0x05,
     DLPF_BANDWIDTH_5HZ = 0x06
   };
-  enum AccelRange : int8_t {
-    ACCEL_RANGE_2G = 0x00,
-    ACCEL_RANGE_4G = 0x08,
-    ACCEL_RANGE_8G = 0x10,
-    ACCEL_RANGE_16G = 0x18
-  };
-  enum GyroRange : int8_t {
-    GYRO_RANGE_250DPS = 0x00,
-    GYRO_RANGE_500DPS = 0x08,
-    GYRO_RANGE_1000DPS = 0x10,
-    GYRO_RANGE_2000DPS = 0x18
-  };
   enum WomRate : int8_t {
     WOM_RATE_0_24HZ = 0x00,
     WOM_RATE_0_49HZ = 0x01,
@@ -88,7 +77,7 @@ class MPU9250 : public Logger {
           imu_(&spi, cs) {}
   void config(TwoWire *i2c, const I2cAddr addr);
   void config(SPIClass *spi, const uint8_t cs);
-  bool begin();
+  bool begin() override;
   bool enableDrdyInt();
   bool disableDrdyInt();
   bool setAccelRange(const AccelRange range);
@@ -100,13 +89,14 @@ class MPU9250 : public Logger {
   bool setDlpfBandwidth(const DlpfBandwidth dlpf);
   inline DlpfBandwidth dlpf_bandwidth() const {return dlpf_bandwidth_;}
   bool enableWom(int16_t threshold_mg, const WomRate wom_rate);
-  void reset();
-  bool read();
-  void waitForData();
-  void getAccel(float& x, float& y, float& z) const;
-  void getGyro(float& x, float& y, float& z) const;
-  void getMag(float& x, float& y, float& z) const;
-  const char* getType() const;
+  void reset() override;
+  bool read() override;
+  void waitForData() override;
+  void getAccel(float& x, float& y, float& z) const override;
+  void getGyro(float& x, float& y, float& z) const override;
+  void getMag(float& x, float& y, float& z) const override;
+  bool setRate(Rate rate) override;
+  const char* getModel() const override;
   inline bool new_imu_data() const {return new_imu_data_;}
   inline float accel_x_mps2() const {return accel_[0];}
   inline float accel_y_mps2() const {return accel_[1];}
@@ -118,8 +108,8 @@ class MPU9250 : public Logger {
   inline float mag_x_ut() const {return mag_[0];}
   inline float mag_y_ut() const {return mag_[1];}
   inline float mag_z_ut() const {return mag_[2];}
-  inline float die_temp_c() const {return temp_;}
-  inline uint8_t whoAmI() const {return who_am_i_;}
+  inline float getTemp() const override {return temp_;}
+  inline uint8_t whoAmI() const override {return who_am_i_;}
 
  private:
   InvensenseImu imu_;