diff options
Diffstat (limited to 'drivers/iio/adc/qcom-spmi-vadc.c')
-rw-r--r-- | drivers/iio/adc/qcom-spmi-vadc.c | 325 |
1 files changed, 15 insertions, 310 deletions
diff --git a/drivers/iio/adc/qcom-spmi-vadc.c b/drivers/iio/adc/qcom-spmi-vadc.c index 0a19761d656c..9e600bfd1765 100644 --- a/drivers/iio/adc/qcom-spmi-vadc.c +++ b/drivers/iio/adc/qcom-spmi-vadc.c @@ -28,6 +28,8 @@ #include <dt-bindings/iio/qcom,spmi-vadc.h> +#include "qcom-vadc-common.h" + /* VADC register and bit definitions */ #define VADC_REVISION2 0x1 #define VADC_REVISION2_SUPPORTED_VADC 1 @@ -75,84 +77,10 @@ #define VADC_DATA 0x60 /* 16 bits */ -#define VADC_CONV_TIME_MIN_US 2000 -#define VADC_CONV_TIME_MAX_US 2100 - -/* Min ADC code represents 0V */ -#define VADC_MIN_ADC_CODE 0x6000 -/* Max ADC code represents full-scale range of 1.8V */ -#define VADC_MAX_ADC_CODE 0xa800 - -#define VADC_ABSOLUTE_RANGE_UV 625000 -#define VADC_RATIOMETRIC_RANGE 1800 - -#define VADC_DEF_PRESCALING 0 /* 1:1 */ -#define VADC_DEF_DECIMATION 0 /* 512 */ -#define VADC_DEF_HW_SETTLE_TIME 0 /* 0 us */ -#define VADC_DEF_AVG_SAMPLES 0 /* 1 sample */ -#define VADC_DEF_CALIB_TYPE VADC_CALIB_ABSOLUTE - -#define VADC_DECIMATION_MIN 512 -#define VADC_DECIMATION_MAX 4096 - -#define VADC_HW_SETTLE_DELAY_MAX 10000 -#define VADC_AVG_SAMPLES_MAX 512 - -#define KELVINMIL_CELSIUSMIL 273150 - -#define PMI_CHG_SCALE_1 -138890 -#define PMI_CHG_SCALE_2 391750000000LL - #define VADC_CHAN_MIN VADC_USBIN #define VADC_CHAN_MAX VADC_LR_MUX3_BUF_PU1_PU2_XO_THERM /** - * struct vadc_map_pt - Map the graph representation for ADC channel - * @x: Represent the ADC digitized code. - * @y: Represent the physical data which can be temperature, voltage, - * resistance. - */ -struct vadc_map_pt { - s32 x; - s32 y; -}; - -/* - * VADC_CALIB_ABSOLUTE: uses the 625mV and 1.25V as reference channels. - * VADC_CALIB_RATIOMETRIC: uses the reference voltage (1.8V) and GND for - * calibration. - */ -enum vadc_calibration { - VADC_CALIB_ABSOLUTE = 0, - VADC_CALIB_RATIOMETRIC -}; - -/** - * struct vadc_linear_graph - Represent ADC characteristics. - * @dy: numerator slope to calculate the gain. - * @dx: denominator slope to calculate the gain. - * @gnd: A/D word of the ground reference used for the channel. - * - * Each ADC device has different offset and gain parameters which are - * computed to calibrate the device. - */ -struct vadc_linear_graph { - s32 dy; - s32 dx; - s32 gnd; -}; - -/** - * struct vadc_prescale_ratio - Represent scaling ratio for ADC input. - * @num: the inverse numerator of the gain applied to the input channel. - * @den: the inverse denominator of the gain applied to the input channel. - */ -struct vadc_prescale_ratio { - u32 num; - u32 den; -}; - -/** * struct vadc_channel_prop - VADC channel property. * @channel: channel number, refer to the channel list. * @calibration: calibration type. @@ -162,9 +90,8 @@ struct vadc_prescale_ratio { * start of conversion. * @avg_samples: ability to provide single result from the ADC * that is an average of multiple measurements. - * @scale_fn: Represents the scaling function to convert voltage + * @scale_fn_type: Represents the scaling function to convert voltage * physical units desired by the client for the channel. - * Referenced from enum vadc_scale_fn_type. */ struct vadc_channel_prop { unsigned int channel; @@ -173,7 +100,7 @@ struct vadc_channel_prop { unsigned int prescale; unsigned int hw_settle_time; unsigned int avg_samples; - unsigned int scale_fn; + enum vadc_scale_fn_type scale_fn_type; }; /** @@ -204,35 +131,6 @@ struct vadc_priv { struct mutex lock; }; -/** - * struct vadc_scale_fn - Scaling function prototype - * @scale: Function pointer to one of the scaling functions - * which takes the adc properties, channel properties, - * and returns the physical result. - */ -struct vadc_scale_fn { - int (*scale)(struct vadc_priv *, const struct vadc_channel_prop *, - u16, int *); -}; - -/** - * enum vadc_scale_fn_type - Scaling function to convert ADC code to - * physical scaled units for the channel. - * SCALE_DEFAULT: Default scaling to convert raw adc code to voltage (uV). - * SCALE_THERM_100K_PULLUP: Returns temperature in millidegC. - * Uses a mapping table with 100K pullup. - * SCALE_PMIC_THERM: Returns result in milli degree's Centigrade. - * SCALE_XOTHERM: Returns XO thermistor voltage in millidegC. - * SCALE_PMI_CHG_TEMP: Conversion for PMI CHG temp - */ -enum vadc_scale_fn_type { - SCALE_DEFAULT = 0, - SCALE_THERM_100K_PULLUP, - SCALE_PMIC_THERM, - SCALE_XOTHERM, - SCALE_PMI_CHG_TEMP, -}; - static const struct vadc_prescale_ratio vadc_prescale_ratios[] = { {.num = 1, .den = 1}, {.num = 1, .den = 3}, @@ -244,44 +142,6 @@ static const struct vadc_prescale_ratio vadc_prescale_ratios[] = { {.num = 1, .den = 10} }; -/* Voltage to temperature */ -static const struct vadc_map_pt adcmap_100k_104ef_104fb[] = { - {1758, -40}, - {1742, -35}, - {1719, -30}, - {1691, -25}, - {1654, -20}, - {1608, -15}, - {1551, -10}, - {1483, -5}, - {1404, 0}, - {1315, 5}, - {1218, 10}, - {1114, 15}, - {1007, 20}, - {900, 25}, - {795, 30}, - {696, 35}, - {605, 40}, - {522, 45}, - {448, 50}, - {383, 55}, - {327, 60}, - {278, 65}, - {237, 70}, - {202, 75}, - {172, 80}, - {146, 85}, - {125, 90}, - {107, 95}, - {92, 100}, - {79, 105}, - {68, 110}, - {59, 115}, - {51, 120}, - {44, 125} -}; - static int vadc_read(struct vadc_priv *vadc, u16 offset, u8 *data) { return regmap_bulk_read(vadc->regmap, vadc->base + offset, data, 1); @@ -553,159 +413,6 @@ err: return ret; } -static int vadc_map_voltage_temp(const struct vadc_map_pt *pts, - u32 tablesize, s32 input, s64 *output) -{ - bool descending = 1; - u32 i = 0; - - if (!pts) - return -EINVAL; - - /* Check if table is descending or ascending */ - if (tablesize > 1) { - if (pts[0].x < pts[1].x) - descending = 0; - } - - while (i < tablesize) { - if ((descending) && (pts[i].x < input)) { - /* table entry is less than measured*/ - /* value and table is descending, stop */ - break; - } else if ((!descending) && - (pts[i].x > input)) { - /* table entry is greater than measured*/ - /*value and table is ascending, stop */ - break; - } - i++; - } - - if (i == 0) { - *output = pts[0].y; - } else if (i == tablesize) { - *output = pts[tablesize - 1].y; - } else { - /* result is between search_index and search_index-1 */ - /* interpolate linearly */ - *output = (((s32)((pts[i].y - pts[i - 1].y) * - (input - pts[i - 1].x)) / - (pts[i].x - pts[i - 1].x)) + - pts[i - 1].y); - } - - return 0; -} - -static void vadc_scale_calib(struct vadc_priv *vadc, u16 adc_code, - const struct vadc_channel_prop *prop, - s64 *scale_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; - - if (*scale_voltage < 0) - *scale_voltage = 0; -} - -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; - - 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 0; -} - -static int vadc_scale_therm(struct vadc_priv *vadc, - const struct vadc_channel_prop *prop, u16 adc_code, - int *result_mdec) -{ - s64 voltage = 0, result = 0; - - vadc_scale_calib(vadc, adc_code, prop, &voltage); - - if (prop->calibration == VADC_CALIB_ABSOLUTE) - voltage = div64_s64(voltage, 1000); - - vadc_map_voltage_temp(adcmap_100k_104ef_104fb, - ARRAY_SIZE(adcmap_100k_104ef_104fb), - voltage, &result); - result *= 1000; - *result_mdec = result; - - return 0; -} - -static int vadc_scale_die_temp(struct vadc_priv *vadc, - const struct vadc_channel_prop *prop, - u16 adc_code, int *result_mdec) -{ - const struct vadc_prescale_ratio *prescale; - s64 voltage = 0; - u64 temp; /* Temporary variable for do_div */ - - vadc_scale_calib(vadc, adc_code, prop, &voltage); - - if (voltage > 0) { - prescale = &vadc_prescale_ratios[prop->prescale]; - temp = voltage * prescale->den; - do_div(temp, prescale->num * 2); - voltage = temp; - } else { - voltage = 0; - } - - voltage -= KELVINMIL_CELSIUSMIL; - *result_mdec = voltage; - - return 0; -} - -static int vadc_scale_chg_temp(struct vadc_priv *vadc, - const struct vadc_channel_prop *prop, - u16 adc_code, int *result_mdec) -{ - const struct vadc_prescale_ratio *prescale; - s64 voltage = 0, result = 0; - - vadc_scale_calib(vadc, adc_code, prop, &voltage); - - prescale = &vadc_prescale_ratios[prop->prescale]; - voltage = voltage * prescale->den; - voltage = div64_s64(voltage, prescale->num); - voltage = ((PMI_CHG_SCALE_1) * (voltage * 2)); - voltage = (voltage + PMI_CHG_SCALE_2); - result = div64_s64(voltage, 1000000); - *result_mdec = result; - - return 0; -} - -static int vadc_decimation_from_dt(u32 value) -{ - if (!is_power_of_2(value) || value < VADC_DECIMATION_MIN || - value > VADC_DECIMATION_MAX) - return -EINVAL; - - return __ffs64(value / VADC_DECIMATION_MIN); -} - static int vadc_prescaling_from_dt(u32 num, u32 den) { unsigned int pre; @@ -742,14 +449,6 @@ static int vadc_avg_samples_from_dt(u32 value) return __ffs64(value); } -static struct vadc_scale_fn scale_fn[] = { - [SCALE_DEFAULT] = {vadc_scale_volt}, - [SCALE_THERM_100K_PULLUP] = {vadc_scale_therm}, - [SCALE_PMIC_THERM] = {vadc_scale_die_temp}, - [SCALE_XOTHERM] = {vadc_scale_therm}, - [SCALE_PMI_CHG_TEMP] = {vadc_scale_chg_temp}, -}; - static int vadc_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int *val, int *val2, long mask) @@ -766,7 +465,13 @@ static int vadc_read_raw(struct iio_dev *indio_dev, if (ret) break; - scale_fn[prop->scale_fn].scale(vadc, prop, adc_code, val); + ret = qcom_vadc_scale(prop->scale_fn_type, + &vadc->graph[prop->calibration], + &vadc_prescale_ratios[prop->prescale], + (prop->calibration == VADC_CALIB_ABSOLUTE), + adc_code, val); + if (ret) + break; return IIO_VAL_INT; case IIO_CHAN_INFO_RAW: @@ -809,7 +514,7 @@ struct vadc_channels { unsigned int prescale_index; enum iio_chan_type type; long info_mask; - unsigned int scale_fn; + enum vadc_scale_fn_type scale_fn_type; }; #define VADC_CHAN(_dname, _type, _mask, _pre, _scale) \ @@ -818,7 +523,7 @@ struct vadc_channels { .prescale_index = _pre, \ .type = _type, \ .info_mask = _mask, \ - .scale_fn = _scale \ + .scale_fn_type = _scale \ }, \ #define VADC_NO_CHAN(_dname, _type, _mask, _pre) \ @@ -976,7 +681,7 @@ static int vadc_get_dt_channel_data(struct device *dev, ret = of_property_read_u32(node, "qcom,decimation", &value); if (!ret) { - ret = vadc_decimation_from_dt(value); + ret = qcom_vadc_decimation_from_dt(value); if (ret < 0) { dev_err(dev, "%02x invalid decimation %d\n", chan, value); @@ -1068,7 +773,7 @@ static int vadc_get_dt_data(struct vadc_priv *vadc, struct device_node *node) return ret; } - prop.scale_fn = vadc_chans[prop.channel].scale_fn; + prop.scale_fn_type = vadc_chans[prop.channel].scale_fn_type; vadc->chan_props[index] = prop; vadc_chan = &vadc_chans[prop.channel]; |