The calibration function calls i2c_smbus_write_byte() and i2c_smbus_read_byte(). These two function calls are replaced with a single call to i2c_smbus_read_byte_data() by this patch. This patch also removes an unnecessary call that reads the CNTRL register a second time. One of the error paths returned -1 if the ADC was not enabled and this patch changes that return value to -EINVAL. Signed-off-by: Brian Masney <masneyb@xxxxxxxxxxxxx> --- drivers/staging/iio/light/tsl2x7x.c | 34 ++++++++++++---------------------- 1 file changed, 12 insertions(+), 22 deletions(-) diff --git a/drivers/staging/iio/light/tsl2x7x.c b/drivers/staging/iio/light/tsl2x7x.c index 6c9f06b..5734628 100644 --- a/drivers/staging/iio/light/tsl2x7x.c +++ b/drivers/staging/iio/light/tsl2x7x.c @@ -542,39 +542,29 @@ static void tsl2x7x_defaults(struct tsl2X7X_chip *chip) static int tsl2x7x_als_calibrate(struct iio_dev *indio_dev) { struct tsl2X7X_chip *chip = iio_priv(indio_dev); - u8 reg_val; int gain_trim_val; int ret; int lux_val; - ret = i2c_smbus_write_byte(chip->client, - (TSL2X7X_CMD_REG | TSL2X7X_CNTRL)); + ret = i2c_smbus_read_byte_data(chip->client, + TSL2X7X_CMD_REG | TSL2X7X_CNTRL); if (ret < 0) { dev_err(&chip->client->dev, - "failed to write CNTRL register, ret=%d\n", ret); + "%s: failed to read from the CNTRL register\n", + __func__); return ret; } - reg_val = i2c_smbus_read_byte(chip->client); - if ((reg_val & (TSL2X7X_CNTL_ADC_ENBL | TSL2X7X_CNTL_PWR_ON)) - != (TSL2X7X_CNTL_ADC_ENBL | TSL2X7X_CNTL_PWR_ON)) { - dev_err(&chip->client->dev, - "%s: failed: ADC not enabled\n", __func__); - return -1; - } - - ret = i2c_smbus_write_byte(chip->client, - (TSL2X7X_CMD_REG | TSL2X7X_CNTRL)); - if (ret < 0) { + if ((ret & (TSL2X7X_CNTL_ADC_ENBL | TSL2X7X_CNTL_PWR_ON)) + != (TSL2X7X_CNTL_ADC_ENBL | TSL2X7X_CNTL_PWR_ON)) { dev_err(&chip->client->dev, - "failed to write ctrl reg: ret=%d\n", ret); - return ret; - } - - reg_val = i2c_smbus_read_byte(chip->client); - if ((reg_val & TSL2X7X_STA_ADC_VALID) != TSL2X7X_STA_ADC_VALID) { + "%s: Device is not powered on and/or ADC is not enabled\n", + __func__); + return -EINVAL; + } else if ((ret & TSL2X7X_STA_ADC_VALID) != TSL2X7X_STA_ADC_VALID) { dev_err(&chip->client->dev, - "%s: failed: STATUS - ADC not valid.\n", __func__); + "%s: The two ADC channels have not completed an integration cycle\n", + __func__); return -ENODATA; } -- 2.9.4 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel