[PATCH 5.16 119/164] iio: imu: st_lsm6dsx: wait for settling time in st_lsm6dsx_read_oneshot

Greg Kroah-Hartman
2022-02-28T18:11:06Z

From: Lorenzo Bianconi <lorenzo@kernel.org>

commit ea85bf906466191b58532bb19f4fbb4591f0a77e upstream.

We need to wait for sensor settling time (~ 3/ODR) before reading data
in st_lsm6dsx_read_oneshot routine in order to avoid corrupted samples.

Fixes: 290a6ce11d93 ("iio: imu: add support to lsm6dsx driver")
Reported-by: Mario Tesi <mario.tesi@st.com>
Tested-by: Mario Tesi <mario.tesi@st.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Link: https://lore.kernel.org/r/b41ebda5535895298716c76d939f9f165fcd2d13.1644098120.git.lorenzo@kernel.org
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

--- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
+++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
@@ -1374,8 +1374,12 @@ static int st_lsm6dsx_read_oneshot(struc
if (err < 0)
return err;

+ /*
+ * we need to wait for sensor settling time before
+ * reading data in order to avoid corrupted samples
+ */
delay = 1000000000 / sensor->odr;
- usleep_range(delay, 2 * delay);
+ usleep_range(3 * delay, 4 * delay);

err = st_lsm6dsx_read_locked(hw, addr, &data, sizeof(data));
if (err < 0)