lkml.org 
[lkml]   [2017]   [Oct]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 4.9 033/105] IIO: BME280: Updates to Humidity readings need ctrl_reg write!
    Date
    4.9-stable review patch.  If anyone has any objections, please let me know.

    ------------------

    From: Colin Parker <colin.parker@aclima.io>

    commit 4b1f0c31f96c45e8521dd84aae50f2aa4aecfb7b upstream.

    The ctrl_reg register needs to be written after any write to
    the humidity registers. The value written to the ctrl_reg register
    does not necessarily need to change, but a write operation must
    occur.

    The regmap_update_bits functions will not write to a register
    if the register value matches the value to be written. This saves
    unnecessary bus operations. The change in this patch forces a bus
    write during the chip_config operation by switching to
    regmap_write_bits.

    This will fix issues where the Humidity Sensor Oversampling bits
    are not updated after initialization.

    Signed-off-by: Colin Parker <colin.parker@aclima.io>
    Acked-by: Andreas Klinger <ak@it-klinger.de>
    Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

    ---
    drivers/iio/pressure/bmp280-core.c | 2 +-
    1 file changed, 1 insertion(+), 1 deletion(-)

    --- a/drivers/iio/pressure/bmp280-core.c
    +++ b/drivers/iio/pressure/bmp280-core.c
    @@ -558,7 +558,7 @@ static int bmp280_chip_config(struct bmp
    u8 osrs = BMP280_OSRS_TEMP_X(data->oversampling_temp + 1) |
    BMP280_OSRS_PRESS_X(data->oversampling_press + 1);

    - ret = regmap_update_bits(data->regmap, BMP280_REG_CTRL_MEAS,
    + ret = regmap_write_bits(data->regmap, BMP280_REG_CTRL_MEAS,
    BMP280_OSRS_TEMP_MASK |
    BMP280_OSRS_PRESS_MASK |
    BMP280_MODE_MASK,

    \
     
     \ /
      Last update: 2017-10-10 22:59    [W:4.253 / U:0.004 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site