6.17-stable review patch. If anyone has any objections, please let me know.
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From: Achim Gratz Achim.Gratz@Stromeko.DE
commit 0bf1bfde53b30da7fd7f4a6c3db5b8e77888958d upstream.
Correction of meas_time_us initialization based on an observation and partial patch by David Lechner.
The constant part of the measurement time (as described in the datasheet and implemented in the BM(P/E)2 Sensor API) was apparently forgotten (it was already correctly applied for the BMP380) and is now used.
There was also another thinko in bmp280_wait_conv: data->oversampling_humid can actually have a value of 0 (for an oversampling_ratio of 1), so it can not be used to detect the presence of the humidity measurement capability. Use data->chip_info->oversampling_humid_avail instead, which is NULL for chips that cannot measure humidity and therefore must skip that part of the calculation.
Closes: https://lore.kernel.org/linux-iio/875xgfg0wz.fsf@Gerda.invalid/ Fixes: 26ccfaa9ddaa ("iio: pressure: bmp280: Use sleep and forced mode for oneshot captures") Suggested-by: David Lechner dlechner@baylibre.com Tested-by: Achim Gratz Achim.Gratz@Stromeko.DE Signed-off-by: Achim Gratz Achim.Gratz@Stromeko.DE 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/pressure/bmp280-core.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-)
--- a/drivers/iio/pressure/bmp280-core.c +++ b/drivers/iio/pressure/bmp280-core.c @@ -1042,13 +1042,16 @@ static int bmp280_wait_conv(struct bmp28 unsigned int reg, meas_time_us; int ret;
- /* Check if we are using a BME280 device */ - if (data->oversampling_humid) - meas_time_us = BMP280_PRESS_HUMID_MEAS_OFFSET + - BIT(data->oversampling_humid) * BMP280_MEAS_DUR; + /* Constant part of the measurement time */ + meas_time_us = BMP280_MEAS_OFFSET;
- else - meas_time_us = 0; + /* + * Check if we are using a BME280 device, + * Humidity measurement time + */ + if (data->chip_info->oversampling_humid_avail) + meas_time_us += BMP280_PRESS_HUMID_MEAS_OFFSET + + BIT(data->oversampling_humid) * BMP280_MEAS_DUR;
/* Pressure measurement time */ meas_time_us += BMP280_PRESS_HUMID_MEAS_OFFSET +