diff options
| author | Jean-Baptiste Maneyrol <jmaneyrol@invensense.com> | 2020-02-06 11:31:04 +0100 |
|---|---|---|
| committer | Jonathan Cameron <Jonathan.Cameron@huawei.com> | 2020-02-14 15:06:25 +0000 |
| commit | 9fc89f796513ca6ce2a3a8f56b90ede7c3d42ba5 (patch) | |
| tree | af097433c64c69b76fc258c0a57c708f5f21022a /drivers/iio/imu | |
| parent | 8abce87d39912e57ade3c141049ffa2eea85846b (diff) | |
| download | linux-9fc89f796513ca6ce2a3a8f56b90ede7c3d42ba5.tar.bz2 | |
iio: imu: inv_mpu6050: update LPF bandwidth settings
As every chip has some little variant in LPF bandwidth values,
use common values that are working for all chips.
Simplify the LPF setting function.
Signed-off-by: Jean-Baptiste Maneyrol <jmaneyrol@invensense.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Diffstat (limited to 'drivers/iio/imu')
| -rw-r--r-- | drivers/iio/imu/inv_mpu6050/inv_mpu_core.c | 30 | ||||
| -rw-r--r-- | drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h | 10 |
2 files changed, 21 insertions, 19 deletions
diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c b/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c index 9ecc667debbe..c4db9086775c 100644 --- a/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c +++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c @@ -707,30 +707,32 @@ error_write_raw_unlock: /** * inv_mpu6050_set_lpf() - set low pass filer based on fifo rate. * - * Based on the Nyquist principle, the sampling rate must - * exceed twice of the bandwidth of the signal, or there - * would be alising. This function basically search for the - * correct low pass parameters based on the fifo rate, e.g, - * sampling frequency. + * Based on the Nyquist principle, the bandwidth of the low + * pass filter must not exceed the signal sampling rate divided + * by 2, or there would be aliasing. + * This function basically search for the correct low pass + * parameters based on the fifo rate, e.g, sampling frequency. * * lpf is set automatically when setting sampling rate to avoid any aliases. */ static int inv_mpu6050_set_lpf(struct inv_mpu6050_state *st, int rate) { - static const int hz[] = {188, 98, 42, 20, 10, 5}; + static const int hz[] = {400, 200, 90, 40, 20, 10}; static const int d[] = { - INV_MPU6050_FILTER_188HZ, INV_MPU6050_FILTER_98HZ, - INV_MPU6050_FILTER_42HZ, INV_MPU6050_FILTER_20HZ, + INV_MPU6050_FILTER_200HZ, INV_MPU6050_FILTER_100HZ, + INV_MPU6050_FILTER_45HZ, INV_MPU6050_FILTER_20HZ, INV_MPU6050_FILTER_10HZ, INV_MPU6050_FILTER_5HZ }; - int i, h, result; + int i, result; u8 data; - h = (rate >> 1); - i = 0; - while ((h < hz[i]) && (i < ARRAY_SIZE(d) - 1)) - i++; - data = d[i]; + data = INV_MPU6050_FILTER_5HZ; + for (i = 0; i < ARRAY_SIZE(hz); ++i) { + if (rate >= hz[i]) { + data = d[i]; + break; + } + } result = inv_mpu6050_set_lpf_regs(st, data); if (result) return result; diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h b/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h index 7ae614052210..9a81098a8b4d 100644 --- a/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h +++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h @@ -370,14 +370,14 @@ enum inv_mpu6050_scan { }; enum inv_mpu6050_filter_e { - INV_MPU6050_FILTER_256HZ_NOLPF2 = 0, - INV_MPU6050_FILTER_188HZ, - INV_MPU6050_FILTER_98HZ, - INV_MPU6050_FILTER_42HZ, + INV_MPU6050_FILTER_NOLPF2 = 0, + INV_MPU6050_FILTER_200HZ, + INV_MPU6050_FILTER_100HZ, + INV_MPU6050_FILTER_45HZ, INV_MPU6050_FILTER_20HZ, INV_MPU6050_FILTER_10HZ, INV_MPU6050_FILTER_5HZ, - INV_MPU6050_FILTER_2100HZ_NOLPF, + INV_MPU6050_FILTER_NOLPF, NUM_MPU6050_FILTER }; |