diff options
Diffstat (limited to 'drivers/iio/adc/qcom-spmi-vadc.c')
-rw-r--r-- | drivers/iio/adc/qcom-spmi-vadc.c | 52 |
1 files changed, 28 insertions, 24 deletions
diff --git a/drivers/iio/adc/qcom-spmi-vadc.c b/drivers/iio/adc/qcom-spmi-vadc.c index c2babe50a0d8..93c0639e21a3 100644 --- a/drivers/iio/adc/qcom-spmi-vadc.c +++ b/drivers/iio/adc/qcom-spmi-vadc.c @@ -1,5 +1,5 @@ /* - * Copyright (c) 2012-2014, The Linux Foundation. All rights reserved. + * Copyright (c) 2012-2016, The Linux Foundation. All rights reserved. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 and @@ -468,27 +468,38 @@ err: return ret; } -static s32 vadc_calibrate(struct vadc_priv *vadc, - const struct vadc_channel_prop *prop, u16 adc_code) +static void vadc_scale_calib(struct vadc_priv *vadc, u16 adc_code, + const struct vadc_channel_prop *prop, + s64 *scale_voltage) { - const struct vadc_prescale_ratio *prescale; - s64 voltage; + *scale_voltage = (adc_code - + vadc->graph[prop->calibration].gnd); + *scale_voltage *= vadc->graph[prop->calibration].dx; + *scale_voltage = div64_s64(*scale_voltage, + vadc->graph[prop->calibration].dy); + if (prop->calibration == VADC_CALIB_ABSOLUTE) + *scale_voltage += + vadc->graph[prop->calibration].dx; - voltage = adc_code - vadc->graph[prop->calibration].gnd; - voltage *= vadc->graph[prop->calibration].dx; - voltage = div64_s64(voltage, vadc->graph[prop->calibration].dy); + if (*scale_voltage < 0) + *scale_voltage = 0; +} - if (prop->calibration == VADC_CALIB_ABSOLUTE) - voltage += vadc->graph[prop->calibration].dx; +static int vadc_scale_volt(struct vadc_priv *vadc, + const struct vadc_channel_prop *prop, u16 adc_code, + int *result_uv) +{ + const struct vadc_prescale_ratio *prescale; + s64 voltage = 0, result = 0; - if (voltage < 0) - voltage = 0; + vadc_scale_calib(vadc, adc_code, prop, &voltage); prescale = &vadc_prescale_ratios[prop->prescale]; - voltage = voltage * prescale->den; + result = div64_s64(voltage, prescale->num); + *result_uv = result; - return div64_s64(voltage, prescale->num); + return 0; } static int vadc_decimation_from_dt(u32 value) @@ -552,11 +563,8 @@ static int vadc_read_raw(struct iio_dev *indio_dev, if (ret) break; - *val = vadc_calibrate(vadc, prop, adc_code); + vadc_scale_volt(vadc, prop, adc_code, val); - /* 2mV/K, return milli Celsius */ - *val /= 2; - *val -= KELVINMIL_CELSIUSMIL; return IIO_VAL_INT; case IIO_CHAN_INFO_RAW: prop = &vadc->chan_props[chan->address]; @@ -564,12 +572,8 @@ static int vadc_read_raw(struct iio_dev *indio_dev, if (ret) break; - *val = vadc_calibrate(vadc, prop, adc_code); + *val = (int)adc_code; return IIO_VAL_INT; - case IIO_CHAN_INFO_SCALE: - *val = 0; - *val2 = 1000; - return IIO_VAL_INT_PLUS_MICRO; default: ret = -EINVAL; break; @@ -617,7 +621,7 @@ struct vadc_channels { #define VADC_CHAN_VOLT(_dname, _pre) \ VADC_CHAN(_dname, IIO_VOLTAGE, \ - BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), \ + BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_PROCESSED),\ _pre) \ /* |