iio: accel: bmi088: Modified the scale calculate

The units after application of scale are 100*m/s^2,
The scale calculation is only for the device
with the range of 3, 6, 12, and 24g,
but some other chips have a range of 2, 4, 6, and 8g.

Modified the scales from formula to a list, the scales in the list are
calculated as 9.8/32768*pow(2,reg41+1)*1.5, refer to datasheet 5.3.4.
The new units after the application of scale are m/s^2.

Reviewed-by: Alexandru Ardelean <ardeleanalex@gmail.com>
Signed-off-by: LI Qingwu <Qing-wu.Li@leica-geosystems.com.cn>
Link: https://lore.kernel.org/r/20220526133359.2261928-2-Qing-wu.Li@leica-geosystems.com.cn
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This commit is contained in:
LI Qingwu 2022-05-26 13:33:54 +00:00 committed by Jonathan Cameron
parent f0ca36b031
commit 733147729a

View file

@ -6,6 +6,7 @@
* Copyright (c) 2018-2021, Topic Embedded Products
*/
#include <linux/bitfield.h>
#include <linux/delay.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
@ -73,6 +74,8 @@
#define BMI088_ACCEL_FIFO_MODE_FIFO 0x40
#define BMI088_ACCEL_FIFO_MODE_STREAM 0x80
#define BMIO088_ACCEL_ACC_RANGE_MSK GENMASK(1, 0)
enum bmi088_accel_axis {
AXIS_X,
AXIS_Y,
@ -119,6 +122,7 @@ struct bmi088_accel_chip_info {
u8 chip_id;
const struct iio_chan_spec *channels;
int num_channels;
const int scale_table[4][2];
};
struct bmi088_accel_data {
@ -280,6 +284,7 @@ static int bmi088_accel_read_raw(struct iio_dev *indio_dev,
struct bmi088_accel_data *data = iio_priv(indio_dev);
struct device *dev = regmap_get_device(data->regmap);
int ret;
int reg;
switch (mask) {
case IIO_CHAN_INFO_RAW:
@ -330,13 +335,14 @@ static int bmi088_accel_read_raw(struct iio_dev *indio_dev,
return ret;
ret = regmap_read(data->regmap,
BMI088_ACCEL_REG_ACC_RANGE, val);
BMI088_ACCEL_REG_ACC_RANGE, &reg);
if (ret)
goto out_read_raw_pm_put;
*val2 = 15 - (*val & 0x3);
*val = 3 * 980;
ret = IIO_VAL_FRACTIONAL_LOG2;
reg = FIELD_GET(BMIO088_ACCEL_ACC_RANGE_MSK, reg);
*val = data->chip_info->scale_table[reg][0];
*val2 = data->chip_info->scale_table[reg][1];
ret = IIO_VAL_INT_PLUS_MICRO;
goto out_read_raw_pm_put;
default:
@ -432,6 +438,7 @@ static const struct bmi088_accel_chip_info bmi088_accel_chip_info_tbl[] = {
.chip_id = 0x1E,
.channels = bmi088_accel_channels,
.num_channels = ARRAY_SIZE(bmi088_accel_channels),
.scale_table = {{0, 897}, {0, 1794}, {0, 3589}, {0, 7178}},
},
};