From: Stephan Gerhold stephan@gerhold.net
commit 8090d67421ddab0ae932abab5a60200598bf0bbb upstream
According to the BMA253 datasheet [1] and BMA250 datasheet [2] the bandwidth value for BMA25x should be set as 01xxx:
"Settings 00xxx result in a bandwidth of 7.81 Hz; [...] It is recommended [...] to use the range from ´01000b´ to ´01111b´ only in order to be compatible with future products."
However, at the moment the drivers sets bandwidth values from 0 to 6, which is not recommended and always results into 7.81 Hz bandwidth according to the datasheet.
Fix this by introducing a bw_offset = 8 = 01000b for BMA25x, so the additional bit is always set for BMA25x.
[1]: https://www.bosch-sensortec.com/media/boschsensortec/downloads/datasheets/bs... [2]: https://datasheet.octopart.com/BMA250-Bosch-datasheet-15540103.pdf
Cc: Peter Meerwald pmeerw@pmeerw.net Fixes: 2017cff24cc0 ("iio:bma180: Add BMA250 chip support") Signed-off-by: Stephan Gerhold stephan@gerhold.net Reviewed-by: Linus Walleij linus.walleij@linaro.org Link: https://lore.kernel.org/r/20210526094408.34298-2-stephan@gerhold.net Cc: Stable@vger.kernel.org Signed-off-by: Jonathan Cameron Jonathan.Cameron@huawei.com [sudip: adjust context] Signed-off-by: Sudip Mukherjee sudipm.mukherjee@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/iio/accel/bma180.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)
--- a/drivers/iio/accel/bma180.c +++ b/drivers/iio/accel/bma180.c @@ -47,7 +47,7 @@ struct bma180_part_info {
u8 int_reset_reg, int_reset_mask; u8 sleep_reg, sleep_mask; - u8 bw_reg, bw_mask; + u8 bw_reg, bw_mask, bw_offset; u8 scale_reg, scale_mask; u8 power_reg, power_mask, lowpower_val; u8 int_enable_reg, int_enable_mask; @@ -103,6 +103,7 @@ struct bma180_part_info {
#define BMA250_RANGE_MASK GENMASK(3, 0) /* Range of accel values */ #define BMA250_BW_MASK GENMASK(4, 0) /* Accel bandwidth */ +#define BMA250_BW_OFFSET 8 #define BMA250_SUSPEND_MASK BIT(7) /* chip will sleep */ #define BMA250_LOWPOWER_MASK BIT(6) #define BMA250_DATA_INTEN_MASK BIT(4) @@ -241,7 +242,8 @@ static int bma180_set_bw(struct bma180_d for (i = 0; i < data->part_info->num_bw; ++i) { if (data->part_info->bw_table[i] == val) { ret = bma180_set_bits(data, data->part_info->bw_reg, - data->part_info->bw_mask, i); + data->part_info->bw_mask, + i + data->part_info->bw_offset); if (ret) { dev_err(&data->client->dev, "failed to set bandwidth\n"); @@ -669,6 +671,7 @@ static const struct bma180_part_info bma .sleep_mask = BMA250_SUSPEND_MASK, .bw_reg = BMA250_BW_REG, .bw_mask = BMA250_BW_MASK, + .bw_offset = BMA250_BW_OFFSET, .scale_reg = BMA250_RANGE_REG, .scale_mask = BMA250_RANGE_MASK, .power_reg = BMA250_POWER_REG,