diff options
| -rw-r--r-- | drivers/staging/iio/adc/ad7298_core.c | 51 |
1 files changed, 23 insertions, 28 deletions
diff --git a/drivers/staging/iio/adc/ad7298_core.c b/drivers/staging/iio/adc/ad7298_core.c index 6dd696f74260..b74b76ffcac8 100644 --- a/drivers/staging/iio/adc/ad7298_core.c +++ b/drivers/staging/iio/adc/ad7298_core.c @@ -45,7 +45,8 @@ static const struct iio_chan_spec ad7298_channels[] = { .indexed = 1, .channel = 0, .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | - IIO_CHAN_INFO_SCALE_SEPARATE_BIT, + IIO_CHAN_INFO_SCALE_SEPARATE_BIT | + IIO_CHAN_INFO_OFFSET_SEPARATE_BIT, .address = AD7298_CH_TEMP, .scan_index = -1, .scan_type = { @@ -80,7 +81,7 @@ static int ad7298_scan_direct(struct ad7298_state *st, unsigned ch) static int ad7298_scan_temp(struct ad7298_state *st, int *val) { - int tmp, ret; + int ret; __be16 buf; buf = cpu_to_be16(AD7298_WRITE | AD7298_TSENSE | @@ -102,24 +103,24 @@ static int ad7298_scan_temp(struct ad7298_state *st, int *val) if (ret) return ret; - tmp = be16_to_cpu(buf) & RES_MASK(AD7298_BITS); + *val = sign_extend32(be16_to_cpu(buf), 11); - /* - * One LSB of the ADC corresponds to 0.25 deg C. - * The temperature reading is in 12-bit twos complement format - */ + return 0; +} + +static int ad7298_get_ref_voltage(struct ad7298_state *st) +{ + int vref; - if (tmp & (1 << (AD7298_BITS - 1))) { - tmp = (4096 - tmp) * 250; - tmp -= (2 * tmp); + if (st->ext_ref) { + vref = regulator_get_voltage(st->reg); + if (vref < 0) + return vref; + return vref / 1000; } else { - tmp *= 250; /* temperature in milli degrees Celsius */ + return AD7298_INTREF_mV; } - - *val = tmp; - - return 0; } static int ad7298_read_raw(struct iio_dev *indio_dev, @@ -130,7 +131,6 @@ static int ad7298_read_raw(struct iio_dev *indio_dev, { int ret; struct ad7298_state *st = iio_priv(indio_dev); - int scale_mv; switch (m) { case IIO_CHAN_INFO_RAW: @@ -155,24 +155,19 @@ static int ad7298_read_raw(struct iio_dev *indio_dev, case IIO_CHAN_INFO_SCALE: switch (chan->type) { case IIO_VOLTAGE: - if (st->ext_ref) { - scale_mv = regulator_get_voltage(st->reg); - if (scale_mv < 0) - return scale_mv; - scale_mv /= 1000; - } else { - scale_mv = AD7298_INTREF_mV; - } - *val = scale_mv; + *val = ad7298_get_ref_voltage(st); *val2 = chan->scan_type.realbits; return IIO_VAL_FRACTIONAL_LOG2; case IIO_TEMP: - *val = 1; - *val2 = 0; - return IIO_VAL_INT_PLUS_MICRO; + *val = ad7298_get_ref_voltage(st); + *val2 = 10; + return IIO_VAL_FRACTIONAL; default: return -EINVAL; } + case IIO_CHAN_INFO_OFFSET: + *val = 1093 - 2732500 / ad7298_get_ref_voltage(st); + return IIO_VAL_INT; } return -EINVAL; } |