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    Subject[PATCH 5.12 091/700] iio: accel: bmc150: Fix bma222 scale unit
    Date
    From: Stephan Gerhold <stephan@gerhold.net>

    commit 6e2a90af0b8d757e850cc023d761ee9a9492e2fe upstream.

    According to sysfs-bus-iio documentation the unit for accelerometer
    values after applying scale/offset should be m/s^2, not g, which explains
    why the scale values for the other variants in bmc150-accel do not match
    exactly the values given in the datasheet.

    To get the correct values, we need to multiply the BMA222 scale values
    by g = 9.80665 m/s^2.

    Fixes: a1a210bf29a1 ("iio: accel: bmc150-accel: Add support for BMA222")
    Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
    Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
    Link: https://lore.kernel.org/r/20210611080903.14384-2-stephan@gerhold.net
    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/accel/bmc150-accel-core.c | 9 +++++----
    1 file changed, 5 insertions(+), 4 deletions(-)

    --- a/drivers/iio/accel/bmc150-accel-core.c
    +++ b/drivers/iio/accel/bmc150-accel-core.c
    @@ -1171,11 +1171,12 @@ static const struct bmc150_accel_chip_in
    /*
    * The datasheet page 17 says:
    * 15.6, 31.3, 62.5 and 125 mg per LSB.
    + * IIO unit is m/s^2 so multiply by g = 9.80665 m/s^2.
    */
    - .scale_table = { {156000, BMC150_ACCEL_DEF_RANGE_2G},
    - {313000, BMC150_ACCEL_DEF_RANGE_4G},
    - {625000, BMC150_ACCEL_DEF_RANGE_8G},
    - {1250000, BMC150_ACCEL_DEF_RANGE_16G} },
    + .scale_table = { {152984, BMC150_ACCEL_DEF_RANGE_2G},
    + {306948, BMC150_ACCEL_DEF_RANGE_4G},
    + {612916, BMC150_ACCEL_DEF_RANGE_8G},
    + {1225831, BMC150_ACCEL_DEF_RANGE_16G} },
    },
    [bma222e] = {
    .name = "BMA222E",

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