This is a note to let you know that I've just added the patch titled
iio: accel: bmc150: Fix bma222 scale unit
to my staging git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git in the staging-testing branch.
The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.)
The patch will be merged to the staging-next branch sometime soon, after it passes testing, and the merge window is open.
If you have any questions about this process, please let me know.
From 6e2a90af0b8d757e850cc023d761ee9a9492e2fe Mon Sep 17 00:00:00 2001
From: Stephan Gerhold stephan@gerhold.net Date: Fri, 11 Jun 2021 10:08:54 +0200 Subject: iio: accel: bmc150: Fix bma222 scale unit
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 --- drivers/iio/accel/bmc150-accel-core.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/drivers/iio/accel/bmc150-accel-core.c b/drivers/iio/accel/bmc150-accel-core.c index a3d08d713362..a80ee0fdabc5 100644 --- a/drivers/iio/accel/bmc150-accel-core.c +++ b/drivers/iio/accel/bmc150-accel-core.c @@ -1145,11 +1145,12 @@ static const struct bmc150_accel_chip_info bmc150_accel_chip_info_tbl[] = { /* * 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",