On Tue, 25 Jul 2017 11:11:14 +0200 Andreas Klinger <[email protected]> wrote:
> If the device is not initialized at least once it happens that the humidity > reading is skipped, which means the special value 0x8000 is delivered. > > For omitting this case the oversampling of the humidity must be set before > the oversampling of the temperature und pressure is set as written in the > datasheet of the BME280. > > Furthermore proper error detection is added in case a skipped value is read > from the device. This is done also for pressure and temperature reading. > Especially it don't make sense to compensate this value and treat it as > regular value. > > Signed-off-by: Andreas Klinger <[email protected]> Applied to the fixes togreg branch of iio.git. Thanks, Jonathan > --- > drivers/iio/pressure/bmp280-core.c | 27 ++++++++++++++++++++++++--- > drivers/iio/pressure/bmp280.h | 5 +++++ > 2 files changed, 29 insertions(+), 3 deletions(-) > > diff --git a/drivers/iio/pressure/bmp280-core.c > b/drivers/iio/pressure/bmp280-core.c > index 4d18826ac63c..d434e2c23833 100644 > --- a/drivers/iio/pressure/bmp280-core.c > +++ b/drivers/iio/pressure/bmp280-core.c > @@ -281,6 +281,11 @@ static int bmp280_read_temp(struct bmp280_data *data, > } > > adc_temp = be32_to_cpu(tmp) >> 12; > + if (adc_temp == BMP280_TEMP_SKIPPED) { > + /* reading was skipped */ > + dev_err(data->dev, "reading temperature skipped\n"); > + return -EIO; > + } > comp_temp = bmp280_compensate_temp(data, adc_temp); > > /* > @@ -316,6 +321,11 @@ static int bmp280_read_press(struct bmp280_data *data, > } > > adc_press = be32_to_cpu(tmp) >> 12; > + if (adc_press == BMP280_PRESS_SKIPPED) { > + /* reading was skipped */ > + dev_err(data->dev, "reading pressure skipped\n"); > + return -EIO; > + } > comp_press = bmp280_compensate_press(data, adc_press); > > *val = comp_press; > @@ -344,6 +354,11 @@ static int bmp280_read_humid(struct bmp280_data *data, > int *val, int *val2) > } > > adc_humidity = be16_to_cpu(tmp); > + if (adc_humidity == BMP280_HUMIDITY_SKIPPED) { > + /* reading was skipped */ > + dev_err(data->dev, "reading humidity skipped\n"); > + return -EIO; > + } > comp_humidity = bmp280_compensate_humidity(data, adc_humidity); > > *val = comp_humidity; > @@ -596,14 +611,20 @@ static const struct bmp280_chip_info bmp280_chip_info = > { > > static int bme280_chip_config(struct bmp280_data *data) > { > - int ret = bmp280_chip_config(data); > + int ret; > u8 osrs = BMP280_OSRS_HUMIDITIY_X(data->oversampling_humid + 1); > > + /* > + * Oversampling of humidity must be set before oversampling of > + * temperature/pressure is set to become effective. > + */ > + ret = regmap_update_bits(data->regmap, BMP280_REG_CTRL_HUMIDITY, > + BMP280_OSRS_HUMIDITY_MASK, osrs); > + > if (ret < 0) > return ret; > > - return regmap_update_bits(data->regmap, BMP280_REG_CTRL_HUMIDITY, > - BMP280_OSRS_HUMIDITY_MASK, osrs); > + return bmp280_chip_config(data); > } > > static const struct bmp280_chip_info bme280_chip_info = { > diff --git a/drivers/iio/pressure/bmp280.h b/drivers/iio/pressure/bmp280.h > index 2c770e13be0e..61347438b779 100644 > --- a/drivers/iio/pressure/bmp280.h > +++ b/drivers/iio/pressure/bmp280.h > @@ -96,6 +96,11 @@ > #define BME280_CHIP_ID 0x60 > #define BMP280_SOFT_RESET_VAL 0xB6 > > +/* BMP280 register skipped special values */ > +#define BMP280_TEMP_SKIPPED 0x80000 > +#define BMP280_PRESS_SKIPPED 0x80000 > +#define BMP280_HUMIDITY_SKIPPED 0x8000 > + > /* Regmap configurations */ > extern const struct regmap_config bmp180_regmap_config; > extern const struct regmap_config bmp280_regmap_config;
