android hal sensor,Android—GSensor驱动与HAL/Framework

1、驱动文件RANGE：

(1)

/*

Range: unit(ug 1g=1 000 000 ug)

option(2g,4g,8g)

G would be defined on android HAL

Precision: bit wide of valid data

Boundary: Max positive count

Gravity_step: gravity value indicated by per count

*/

#define FREAD_MASK0 /* enabled(1<<1) only if reading MSB 8bits*/

#define MMA845X_RANGE2000000

/* mma8452 */

#define MMA8452_PRECISION 12

#define MMA8452_BOUNDARY (0x1 << (MMA8452_PRECISION - 1))

#define MMA8452_GRAVITY_STEP MMA845X_RANGE / MMA8452_BOUNDARY

(2)

result = ((int)high_byte << (MMA8452_PRECISION-8)) | ((int)low_byte >> (16-MMA8452_PRECISION)); //合并数据

if (result < MMA8452_BOUNDARY) //判断符号

result = result* MMA8452_GRAVITY_STEP;

else

result = ~( ((~result & (0x7fff>>(16-MMA8452_PRECISION)) ) + 1) * MMA8452_GRAVITY_STEP) + 1;

2、HAL层

(1)MMA IOCTL (mma8452.h )

#define MMAIO 0xA1

/* IOCTLs for MMA8452 library */

#define ECS_IOCTL_INIT _IO(MMAIO, 0x01)

// #define ECS_IOCTL_RESET _IO(MMAIO, 0x04)

#define ECS_IOCTL_CLOSE _IO(MMAIO, 0x02)

#define ECS_IOCTL_START _IO(MMAIO, 0x03)

// #define ECS_IOCTL_GETDATA _IOR(MMAIO, 0x08, char[RBUFF_SIZE+1])

/* IOCTLs for APPs */

#define ECS_IOCTL_APP_SET_RATE _IOW(MMAIO, 0x10, char)

(2)(nusensors.h)

#define ACCELERATION_RATIO_ANDROID_TO_HW (9.80665f / 1000000)

(3)(MmaSensor.cpp)

void MmaSensor::processEvent(int code, int value)

{

switch (code) {

case EVENT_TYPE_ACCEL_X:

mPendingMask |= 1<

mPendingEvents[Accelerometer].acceleration.x = value * ACCELERATION_RATIO_ANDROID_TO_HW;

break;

case EVENT_TYPE_ACCEL_Y:

mPendingMask |= 1<

mPendingEvents[Accelerometer].acceleration.y = value * ACCELERATION_RATIO_ANDROID_TO_HW;

break;

case EVENT_TYPE_ACCEL_Z:

mPendingMask |= 1<

mPendingEvents[Accelerometer].acceleration.z = value * ACCELERATION_RATIO_ANDROID_TO_HW;

break;

}

}

(4)Sensor_params.h

//ACCEL_ID_LIS331

#define ACCEL_LIS331_RANGE (2.480f*GRAVITY_EARTH)

#define ACCEL_LIS331_RESOLUTION (.001f*GRAVITY_EARTH)

#define ACCEL_LIS331_POWER (1.0f)

//ACCEL_ID_LSM303DLX

#define ACCEL_LSM303DLX_RANGE (2.480f*GRAVITY_EARTH)

#define ACCEL_LSM303DLX_RESOLUTION (0.001f*GRAVITY_EARTH)

#define ACCEL_LSM303DLX_POWER (1.0f)

//ACCEL_ID_LIS3DH

#define ACCEL_LIS3DH_RANGE (2.480f*GRAVITY_EARTH)

#define ACCEL_LIS3DH_RESOLUTION (0.001f*GRAVITY_EARTH)

#define ACCEL_LIS3DH_POWER (1.0f)

//ACCEL_ID_KXSD9

#define ACCEL_KXSD9_RANGE (2.5006f*GRAVITY_EARTH)

#define ACCEL_KXSD9_RESOLUTION (0.001f*GRAVITY_EARTH)

#define ACCEL_KXSD9_POWER (1.0f)

//ACCEL_ID_KXTF9

#define ACCEL_KXTF9_RANGE (1.0f*GRAVITY_EARTH)

#define ACCEL_KXTF9_RESOLUTION (0.033f*GRAVITY_EARTH)

#define ACCEL_KXTF9_POWER (0.35f)

//ACCEL_ID_BMA150

#define ACCEL_BMA150_RANGE (2.0f*GRAVITY_EARTH)

#define ACCEL_BMA150_RESOLUTION (0.004f*GRAVITY_EARTH)

#define ACCEL_BMA150_POWER (0.2f)

//ACCEL_ID_BMA222

#define ACCEL_BMA222_RANGE (2.0f*GRAVITY_EARTH)

#define ACCEL_BMA222_RESOLUTION (0.001f*GRAVITY_EARTH)

#define ACCEL_BMA222_POWER (0.1f)

//ACCEL_ID_BMA250

#define ACCEL_BMA250_RANGE (2.0f*GRAVITY_EARTH)

#define ACCEL_BMA250_RESOLUTION (0.00391f*GRAVITY_EARTH)

#define ACCEL_BMA250_POWER (0.139f)

//ACCEL_ID_ADXL34X

#define ACCEL_ADXL34X_RANGE (2.0f*GRAVITY_EARTH)

#define ACCEL_ADXL34X_RESOLUTION (0.001f*GRAVITY_EARTH)

#define ACCEL_ADXL34X_POWER (1.0f)

//ACCEL_ID_MMA8450

#define ACCEL_MMA8450_RANGE (2.0f*GRAVITY_EARTH)

#define ACCEL_MMA8450_RESOLUTION (0.001f*GRAVITY_EARTH)

#define ACCEL_MMA8450_POWER (1.0f)

//ACCEL_ID_MMA845X

#define ACCEL_MMA845X_RANGE (2.0f*GRAVITY_EARTH)

#define ACCEL_MMA845X_RESOLUTION (0.001f*GRAVITY_EARTH)

#define ACCEL_MMA845X_POWER (1.0f)

//ACCEL_ID_MPU6050

#define ACCEL_MPU6050_RANGE (2.0f*GRAVITY_EARTH)

#define ACCEL_MPU6050_RESOLUTION (0.004f*GRAVITY_EARTH)

#define ACCEL_MPU6050_POWER (0.0f)

/******************************************/

//GYRO MPU3050

#define RAD_P_DEG (3.14159f/180.0f)

#define GYRO_MPU3050_RANGE (2000.0f*RAD_P_DEG)

#define GYRO_MPU3050_RESOLUTION (32.8f*RAD_P_DEG)

#define GYRO_MPU3050_POWER (6.1f)

//GYRO MPU6050

#define GYRO_MPU6050_RANGE (2000.0f*RAD_P_DEG)

#define GYRO_MPU6050_RESOLUTION (16.4f*RAD_P_DEG)

#define GYRO_MPU6050_POWER (5.5f)

(6)MPLSensor.cpp

void MPLSensor::fillAccel(unsigned char accel, struct sensor_t *list)

{

switch (accel) {

case ACCEL_ID_LIS331:

list[Accelerometer].maxRange = ACCEL_LIS331_RANGE;

list[Accelerometer].resolution = ACCEL_LIS331_RESOLUTION;

list[Accelerometer].power = ACCEL_LIS331_POWER;

break;

case ACCEL_ID_LIS3DH:

list[Accelerometer].maxRange = ACCEL_LIS3DH_RANGE;

list[Accelerometer].resolution = ACCEL_LIS3DH_RESOLUTION;

list[Accelerometer].power = ACCEL_LIS3DH_POWER;

break;

case ACCEL_ID_KXSD9:

list[Accelerometer].maxRange = ACCEL_KXSD9_RANGE;

list[Accelerometer].resolution = ACCEL_KXSD9_RESOLUTION;

list[Accelerometer].power = ACCEL_KXSD9_POWER;

break;

case ACCEL_ID_KXTF9:

list[Accelerometer].maxRange = ACCEL_KXTF9_RANGE;

list[Accelerometer].resolution = ACCEL_KXTF9_RESOLUTION;

list[Accelerometer].power = ACCEL_KXTF9_POWER;

break;

case ACCEL_ID_BMA150:

list[Accelerometer].maxRange = ACCEL_BMA150_RANGE;

list[Accelerometer].resolution = ACCEL_BMA150_RESOLUTION;

list[Accelerometer].power = ACCEL_BMA150_POWER;

break;

case ACCEL_ID_BMA222:

list[Accelerometer].maxRange = ACCEL_BMA222_RANGE;

list[Accelerometer].resolution = ACCEL_BMA222_RESOLUTION;

list[Accelerometer].power = ACCEL_BMA222_POWER;

break;

case ACCEL_ID_BMA250:

list[Accelerometer].maxRange = ACCEL_BMA250_RANGE;

list[Accelerometer].resolution = ACCEL_BMA250_RESOLUTION;

list[Accelerometer].power = ACCEL_BMA250_POWER;

break;

case ACCEL_ID_ADXL34X:

list[Accelerometer].maxRange = ACCEL_ADXL34X_RANGE;

list[Accelerometer].resolution = ACCEL_ADXL34X_RESOLUTION;

list[Accelerometer].power = ACCEL_ADXL34X_POWER;

break;

case ACCEL_ID_MMA8450:

list[Accelerometer].maxRange = ACCEL_MMA8450_RANGE;

list[Accelerometer].maxRange = ACCEL_MMA8450_RANGE;

list[Accelerometer].maxRange = ACCEL_MMA8450_RANGE;

break;

case ACCEL_ID_MMA845X:

list[Accelerometer].maxRange = ACCEL_MMA845X_RANGE;

list[Accelerometer].resolution = ACCEL_MMA845X_RESOLUTION;

list[Accelerometer].power = ACCEL_MMA845X_POWER;

break;

case ACCEL_ID_MPU6050:

list[Accelerometer].maxRange = ACCEL_MPU6050_RANGE;

list[Accelerometer].resolution = ACCEL_MPU6050_RESOLUTION;

list[Accelerometer].power = ACCEL_MPU6050_POWER;

break;

default:

ALOGE("unknown accel id -- accel params will be wrong.");

break;

}

}

3、Framework-Java-->SensorEvent.java

* public void onSensorChanged(SensorEvent event)

* {

* // alpha is calculated as t / (t + dT)

* // with t, the low-pass filter's time-constant

* // and dT, the event delivery rate

*

* final float alpha = 0.8;

*

* gravity[0] = alpha * gravity[0] + (1 - alpha) * event.values[0];

* gravity[1] = alpha * gravity[1] + (1 - alpha) * event.values[1];

* gravity[2] = alpha * gravity[2] + (1 - alpha) * event.values[2];

*

* linear_acceleration[0] = event.values[0] - gravity[0];

* linear_acceleration[1] = event.values[1] - gravity[1];

* linear_acceleration[2] = event.values[2] - gravity[2];

* }