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| author | Ching-Kang Yen <chingkang@chromium.org> | 2020-01-16 16:11:40 +0800 |
|---|---|---|
| committer | Commit Bot <commit-bot@chromium.org> | 2020-01-31 03:14:22 +0000 |
| commit | 036e9f7b214b763524497550aae0ee94df8fd536 (patch) | |
| tree | 8bc2e0a15268dcd8a8ed8ef03af7c716d46e8d0a /driver/accelgyro_bmi160.c | |
| parent | 876de6a603072fe121afe99fbda5d4f0e9efd266 (diff) | |
| download | chrome-ec-036e9f7b214b763524497550aae0ee94df8fd536.tar.gz | |
driver: bmi160: Fix rounding error in set_offset() and get_offset()
The original set_offset() and get_offset() codes in the
driver/accelgyro_bmi160 use simple divisions to write the data.
The more times the set_offset() and get_offset() is used, the
data will get closer to 0.
Fixing it by replacing simple division to round_divide(), division
that round to nearest, in the common/math_util.c.
BRANCH=octopus
BUG=b:146823505
TEST=Testing on octopus:ampton on branch [firmware-octopus-11297.B].
Checking the data did not rounding to 0.
Change-Id: Ide9df9e32fc501e63d6f952cb8254df7662afd23
Signed-off-by: Ching-Kang Yen <chingkang@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2002998
Reviewed-by: Gwendal Grignou <gwendal@chromium.org>
Commit-Queue: Gwendal Grignou <gwendal@chromium.org>
Diffstat (limited to 'driver/accelgyro_bmi160.c')
| -rw-r--r-- | driver/accelgyro_bmi160.c | 21 |
1 files changed, 13 insertions, 8 deletions
diff --git a/driver/accelgyro_bmi160.c b/driver/accelgyro_bmi160.c index 9f043ce862..2c29295988 100644 --- a/driver/accelgyro_bmi160.c +++ b/driver/accelgyro_bmi160.c @@ -506,8 +506,10 @@ static int get_offset(const struct motion_sensor_t *s, BMI160_OFFSET_ACC70 + i, &val); if (val > 0x7f) val = -256 + val; - v[i] = val * BMI160_OFFSET_ACC_MULTI_MG / - BMI160_OFFSET_ACC_DIV_MG; + v[i] = round_divide( + (int64_t)val * BMI160_OFFSET_ACC_MULTI_MG, + BMI160_OFFSET_ACC_DIV_MG); + } break; case MOTIONSENSE_TYPE_GYRO: @@ -526,8 +528,9 @@ static int get_offset(const struct motion_sensor_t *s, val |= ((val98 >> (2 * i)) & 0x3) << 8; if (val > 0x1ff) val = -1024 + val; - v[i] = val * BMI160_OFFSET_GYRO_MULTI_MDS / - BMI160_OFFSET_GYRO_DIV_MDS; + v[i] = round_divide( + (int64_t)val * BMI160_OFFSET_GYRO_MULTI_MDS, + BMI160_OFFSET_GYRO_DIV_MDS); } break; #ifdef CONFIG_MAG_BMI160_BMM150 @@ -565,8 +568,9 @@ static int set_offset(const struct motion_sensor_t *s, switch (s->type) { case MOTIONSENSE_TYPE_ACCEL: for (i = X; i <= Z; i++) { - val = v[i] * BMI160_OFFSET_ACC_DIV_MG / - BMI160_OFFSET_ACC_MULTI_MG; + val = round_divide( + (int64_t)v[i] * BMI160_OFFSET_ACC_DIV_MG, + BMI160_OFFSET_ACC_MULTI_MG); if (val > 127) val = 127; if (val < -128) @@ -582,8 +586,9 @@ static int set_offset(const struct motion_sensor_t *s, break; case MOTIONSENSE_TYPE_GYRO: for (i = X; i <= Z; i++) { - val = v[i] * BMI160_OFFSET_GYRO_DIV_MDS / - BMI160_OFFSET_GYRO_MULTI_MDS; + val = round_divide( + (int64_t)v[i] * BMI160_OFFSET_GYRO_DIV_MDS, + BMI160_OFFSET_GYRO_MULTI_MDS); if (val > 511) val = 511; if (val < -512) |