From: Slaveyko Slaveykov <sis@xxxxxxxxxxx> commit cf5b1385d748b2f91b0c05bb301fcaf9bdbad385 upstream. After an I2C reset command, the mlx90632 needs some time before responding to other I2C commands. Without that delay, there is a chance that the I2C command(s) after the reset will not be accepted. Signed-off-by: Slaveyko Slaveykov <sis@xxxxxxxxxxx> Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx> Reviewed-by: Crt Mori <cmo@xxxxxxxxxxx> Fixes: e02472f74a81 ("iio:temperature:mlx90632: Adding extended calibration option") Link: https://lore.kernel.org/r/20201216115720.12404-2-sis@xxxxxxxxxxx Cc: <Stable@xxxxxxxxxxxxxxx> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/iio/temperature/mlx90632.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/drivers/iio/temperature/mlx90632.c +++ b/drivers/iio/temperature/mlx90632.c @@ -248,6 +248,12 @@ static int mlx90632_set_meas_type(struct if (ret < 0) return ret; + /* + * Give the mlx90632 some time to reset properly before sending a new I2C command + * if this is not done, the following I2C command(s) will not be accepted. + */ + usleep_range(150, 200); + ret = regmap_write_bits(regmap, MLX90632_REG_CONTROL, (MLX90632_CFG_MTYP_MASK | MLX90632_CFG_PWR_MASK), (MLX90632_MTYP_STATUS(type) | MLX90632_PWR_STATUS_HALT));