blob: b0b35ded6fea8dbc8bda7d4d3f71cb9bbddb97b9 [file] [log] [blame]
/* Copyright 2015 The Chromium OS Authors. All rights reserved.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
/* Online magnetometer calibration */
#ifndef __CROS_EC_MAG_CAL_H
#define __CROS_EC_MAG_CAL_H
#include "math_util.h"
#include "mat44.h"
#include "vec4.h"
#define MAG_CAL_MAX_SAMPLES 0xffff
#define MAG_CAL_MIN_BATCH_WINDOW_US SECOND
#define MAG_CAL_MIN_BATCH_SIZE 25 /* samples */
struct mag_cal_t {
/*
* Matric for sphere fitting:
* +----+----+----+----+
* | xx | xy | xz | x |
* +----+----+----+----+
* | xy | yy | yz | y |
* +----+----+----+----+
* | xz | yz | zz | z |
* +----+----+----+----+
* | x | y | z | 1 |
* +----+----+----+----+
*/
mat44_fp_t acc;
fpv4_t acc_w;
fp_t radius;
intv3_t bias;
/* number of samples needed to calibrate */
uint16_t batch_size;
uint16_t nsamples;
};
void init_mag_cal(struct mag_cal_t *moc);
int mag_cal_update(struct mag_cal_t *moc, const intv3_t v);
#endif /* __CROS_EC_MAG_CAL_H */