int bma020_write_ee(unsigned char addr, unsigned char data)
{
int comres;
if (p_bma020==0) /* check pointers */
return E_BMA020_NULL_PTR;
if (p_bma020->delay_msec == 0)
return E_BMA020_NULL_PTR;
comres = bma020_set_ee_w( BMA020_EE_W_ON );
addr|=0x20; /* add eeprom address offset to image address if not applied */
comres += bma020_write_reg(addr, &data, 1 );
p_bma020->delay_msec( BMA020_EE_W_DELAY );
comres += bma020_set_ee_w( BMA020_EE_W_OFF);
return comres;
}
int bma020_calibrate(bma020acc_t orientation, int *tries)
{
unsigned short offset_x, offset_y, offset_z;
unsigned short old_offset_x, old_offset_y, old_offset_z;
unsigned short changed_offset_x, changed_offset_y, changed_offset_z;
int need_calibration=0, min_max_ok=0;
int ltries;
int retry = 30;
bma020acc_t min,max,avg;
printk("[%s] +\n", __func__);
bma020_set_range(BMA020_RANGE_2G);
bma020_set_bandwidth(BMA020_BW_25HZ);
bma020_set_ee_w(1);
bma020_get_offset(0, &offset_x);
bma020_get_offset(1, &offset_y);
bma020_get_offset(2, &offset_z);
old_offset_x = offset_x;
old_offset_y = offset_y;
old_offset_z = offset_z;
ltries = *tries;
printk("[%s] old offset_x = %d, offset_y = %d, offset_z = %d\n", __func__, old_offset_x, offset_y, offset_z);
orientation.x = 0;
orientation.y = 0;
orientation.z = 1;
do {
bma020_read_accel_avg(10, &min, &max, &avg); /* read acceleration data min, max, avg */
min_max_ok = bma020_verify_min_max(min, max, avg);
if(!min_max_ok)
{
retry--;
if(retry <= 0)
return (-1);
}
/* check if calibration is needed */
if (min_max_ok)
need_calibration = bma020_calc_new_offset(orientation, avg, &offset_x, &offset_y, &offset_z);
if (*tries==0) /*number of maximum tries reached? */
break;
if (need_calibration) {
/* when needed calibration is updated in image */
printk("[%s] need calibration. tries = %d. changed offset x = %d, y = %d, z = %d\n", __func__, *tries, offset_x, offset_y, offset_z);
(*tries)--;
bma020_set_offset(0, offset_x);
bma020_set_offset(1, offset_y);
bma020_set_offset(2, offset_z);
bma020_pause(20);
}
printk("\n");
} while (need_calibration || !min_max_ok);
if (*tries>0 && *tries < ltries) {
printk("[%s] eeprom is updated. new offset x=%d, y=%d, z=%d\n",
__func__, offset_x, offset_y, offset_z);
if (old_offset_x!= offset_x)
bma020_set_offset_eeprom(0, offset_x);
if (old_offset_y!= offset_y)
bma020_set_offset_eeprom(1,offset_y);
if (old_offset_z!= offset_z)
bma020_set_offset_eeprom(2, offset_z);
}
printk("[%s] tries = %d\n", __func__, *tries);
bma020_set_ee_w(0);
bma020_pause(20);
*tries = ltries - *tries;
printk("[%s] -\n", __func__);
return !need_calibration;
}
