2 * Copyright (C) 2014 Intel Corporation.
5 #ifndef __CALIBRATION_H__
6 #define __CALIBRATION_H__
11 #define COMPASS_CALIBRATION_PATH "/data/compass.conf"
13 #define EPSILON 0.000000001
16 /* We'll have multiple calibration levels
17 * so that we can provide an estimation as fast as possible
19 static const float min_diffs[CAL_STEPS] = { 0.2, 0.4, 0.6, 1.0 };
20 static const float max_sqr_errs[CAL_STEPS] = { 10.0, 8.0, 5.0, 3.5 };
21 static const unsigned int lookback_counts[CAL_STEPS] = { 3, 4, 5, 6 };
25 #define RAW_DATA_FULL_PATH "/data/raw_compass_data_full_%d.txt"
26 #define RAW_DATA_SELECTED_PATH "/data/raw_compass_data_selected_%d.txt"
30 #define GYRO_MAX_ERR 0.05f
31 #define GYRO_DS_SIZE 8
34 /* hard iron offsets */
37 /* soft iron matrix */
38 double w_invert[3][3];
40 /* geomagnetic strength */
44 float sample[DS_SIZE][3];
45 unsigned int sample_count;
52 float sample[GYRO_DS_SIZE][3];
55 typedef double mat_input_t[DS_SIZE][3];
57 void calibrate_compass (struct sensors_event_t* event, struct sensor_info_t* info, int64_t time);
58 void compass_read_data (struct sensor_info_t* info);
59 void compass_store_data (struct sensor_info_t* info);
61 void calibrate_gyro(struct sensors_event_t* event, struct sensor_info_t* info);
62 void gyro_cal_init(struct sensor_info_t* info);