Hi Ramakrishna, >Add changes to support different scale functions to convert adc code to >physical units. > >Signed-off-by: Rama Krishna Phani A <rphani@xxxxxxxxxxxxxx> >--- > drivers/iio/adc/qcom-spmi-vadc.c | 319 ++++++++++++++++++++++++++++++--------- > 1 file changed, 249 insertions(+), 70 deletions(-) > >diff --git a/drivers/iio/adc/qcom-spmi-vadc.c b/drivers/iio/adc/qcom-spmi-vadc.c >index c2babe5..e605a9d 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 >@@ -84,7 +84,7 @@ > #define VADC_MAX_ADC_CODE 0xa800 > > #define VADC_ABSOLUTE_RANGE_UV 625000 >-#define VADC_RATIOMETRIC_RANGE_UV 1800000 >+#define VADC_RATIOMETRIC_RANGE 1800 > > #define VADC_DEF_PRESCALING 0 /* 1:1 */ > #define VADC_DEF_DECIMATION 0 /* 512 */ >@@ -92,6 +92,8 @@ > #define VADC_DEF_AVG_SAMPLES 0 /* 1 sample */ > #define VADC_DEF_CALIB_TYPE VADC_CALIB_ABSOLUTE > >+#define VADC_DEF_SCALE_FN SCALE_DEFAULT >+ > #define VADC_DECIMATION_MIN 512 > #define VADC_DECIMATION_MAX 4096 > >@@ -100,9 +102,43 @@ > > #define KELVINMIL_CELSIUSMIL 273150 > >+#define PMI_CHG_SCALE_1 -138890 >+#define PMI_CHG_SCALE_2 391750000000 >+ > #define VADC_CHAN_MIN VADC_USBIN > #define VADC_CHAN_MAX VADC_LR_MUX3_BUF_PU1_PU2_XO_THERM > >+/** >+ * 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 >+ * %SCALE_NONE: Do not use this scaling type. >+ */ >+enum vadc_scale_fn_type { >+ SCALE_DEFAULT = 0, >+ SCALE_THERM_100K_PULLUP, >+ SCALE_PMIC_THERM, >+ SCALE_XOTHERM, >+ SCALE_PMI_CHG_TEMP, >+ SCALE_NONE, >+}; >+ >+/** >+ * 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 >@@ -148,6 +184,9 @@ 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_function: 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; >@@ -156,6 +195,7 @@ struct vadc_channel_prop { > unsigned int prescale; > unsigned int hw_settle_time; > unsigned int avg_samples; >+ unsigned int scale_function; > }; > > /** >@@ -197,6 +237,44 @@ struct vadc_priv { > {.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); >@@ -418,7 +496,7 @@ static int vadc_measure_ref_points(struct vadc_priv *vadc) > u16 read_1, read_2; > int ret; > >- vadc->graph[VADC_CALIB_RATIOMETRIC].dx = VADC_RATIOMETRIC_RANGE_UV; >+ vadc->graph[VADC_CALIB_RATIOMETRIC].dx = VADC_RATIOMETRIC_RANGE; > vadc->graph[VADC_CALIB_ABSOLUTE].dx = VADC_ABSOLUTE_RANGE_UV; > > prop = vadc_get_channel(vadc, VADC_REF_1250MV); >@@ -468,27 +546,128 @@ static int vadc_measure_ref_points(struct vadc_priv *vadc) > return ret; > } > >-static s32 vadc_calibrate(struct vadc_priv *vadc, >- const struct vadc_channel_prop *prop, u16 adc_code) >+static int vadc_map_voltage_temp(const struct vadc_map_pt *pts, >+ u32 tablesize, s32 input, s64 *output) > { >- const struct vadc_prescale_ratio *prescale; >- s64 voltage; >+ 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 == 1) && (pts[i].x < input)) { Just if (descending) instead of (descending == 1) and so on for the below as well >+ /* table entry is less than measured*/ >+ /* value and table is descending, stop */ >+ break; >+ } else if ((descending == 0) && >+ (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); >+ } hmm, so for descending, input - pts[i -1].x is negative and we are adding that to pts[i-1].y, is that correct ? > >- voltage = adc_code - vadc->graph[prop->calibration].gnd; >- voltage *= vadc->graph[prop->calibration].dx; >- voltage = div64_s64(voltage, vadc->graph[prop->calibration].dy); >+ 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) >- voltage += vadc->graph[prop->calibration].dx; >+ *scale_voltage += >+ vadc->graph[prop->calibration].dx; > >- if (voltage < 0) >- voltage = 0; >+ if (*scale_voltage < 0) >+ *scale_voltage = 0; >+} > >- prescale = &vadc_prescale_ratios[prop->prescale]; >+static s64 vadc_scale_fn(struct vadc_priv *vadc, >+ const struct vadc_channel_prop *prop, u16 adc_code) >+{ >+ const struct vadc_prescale_ratio *prescale; >+ s64 voltage = 0, result = 0; >+ int ret; > >- voltage = voltage * prescale->den; >+ switch (prop->scale_function) { > >- return div64_s64(voltage, prescale->num); >+ case SCALE_DEFAULT: >+ vadc_scale_calib(vadc, adc_code, prop, &voltage); >+ >+ prescale = &vadc_prescale_ratios[prop->prescale]; >+ voltage = voltage * prescale->den; >+ return div64_s64(voltage, prescale->num); >+ This is the default case that exists today. So the code rearrange for making the vadc_scale_calib common can be introduced in one patch and the rest of the below new scaling functions in subsequent patches. >+ case SCALE_THERM_100K_PULLUP: >+ case SCALE_XOTHERM: >+ vadc_scale_calib(vadc, adc_code, prop, &voltage); >+ >+ if (prop->calibration == VADC_CALIB_ABSOLUTE) >+ do_div(voltage, 1000); >+ >+ vadc_map_voltage_temp(adcmap_100k_104ef_104fb, >+ ARRAY_SIZE(adcmap_100k_104ef_104fb), >+ voltage, &result); >+ result *= 1000; >+ return result; >+ >+ case SCALE_PMIC_THERM: >+ vadc_scale_calib(vadc, adc_code, prop, &voltage); >+ >+ if (voltage > 0) { >+ prescale = &vadc_prescale_ratios[prop->prescale]; >+ voltage = voltage * prescale->den; >+ do_div(voltage, prescale->num * 2); >+ } else { >+ voltage = 0; >+ } >+ >+ voltage -= KELVINMIL_CELSIUSMIL; >+ >+ return voltage; >+ >+ case SCALE_PMI_CHG_TEMP: >+ 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); >+ return div64_s64(voltage, 1000000); >+ >+ default: >+ ret = -EINVAL; >+ break; >+ } >+ >+ return ret; > } > > static int vadc_decimation_from_dt(u32 value) >@@ -552,11 +731,8 @@ static int vadc_read_raw(struct iio_dev *indio_dev, > if (ret) > break; > >- *val = vadc_calibrate(vadc, prop, adc_code); >+ *val = vadc_scale_fn(vadc, prop, adc_code); > >- /* 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 +740,8 @@ 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; >@@ -613,11 +785,13 @@ struct vadc_channels { > }, \ > > #define VADC_CHAN_TEMP(_dname, _pre) \ >- VADC_CHAN(_dname, IIO_TEMP, BIT(IIO_CHAN_INFO_PROCESSED), _pre) \ >+ VADC_CHAN(_dname, IIO_TEMP, \ >+ BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_PROCESSED), \ >+ _pre) \ > > #define VADC_CHAN_VOLT(_dname, _pre) \ >- VADC_CHAN(_dname, IIO_VOLTAGE, \ >- BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), \ >+ VADC_CHAN(_dname, IIO_VOLTAGE, \ >+ BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_PROCESSED),\ > _pre) \ > For this and the below changes to VADC_CHAN_VOLT to TEMP, why is that done ? Now both macros are setting the same flags. > /* >@@ -637,12 +811,11 @@ struct vadc_channels { > VADC_CHAN_TEMP(DIE_TEMP, 0) > VADC_CHAN_VOLT(REF_625MV, 0) > VADC_CHAN_VOLT(REF_1250MV, 0) >- VADC_CHAN_VOLT(CHG_TEMP, 0) >+ VADC_CHAN_TEMP(CHG_TEMP, 0) > VADC_CHAN_VOLT(SPARE1, 0) > VADC_CHAN_VOLT(SPARE2, 0) > VADC_CHAN_VOLT(GND_REF, 0) > VADC_CHAN_VOLT(VDD_VADC, 0) >- > VADC_CHAN_VOLT(P_MUX1_1_1, 0) > VADC_CHAN_VOLT(P_MUX2_1_1, 0) > VADC_CHAN_VOLT(P_MUX3_1_1, 0) >@@ -659,7 +832,6 @@ struct vadc_channels { > VADC_CHAN_VOLT(P_MUX14_1_1, 0) > VADC_CHAN_VOLT(P_MUX15_1_1, 0) > VADC_CHAN_VOLT(P_MUX16_1_1, 0) >- > VADC_CHAN_VOLT(P_MUX1_1_3, 1) > VADC_CHAN_VOLT(P_MUX2_1_3, 1) > VADC_CHAN_VOLT(P_MUX3_1_3, 1) >@@ -676,7 +848,6 @@ struct vadc_channels { > VADC_CHAN_VOLT(P_MUX14_1_3, 1) > VADC_CHAN_VOLT(P_MUX15_1_3, 1) > VADC_CHAN_VOLT(P_MUX16_1_3, 1) >- > VADC_CHAN_VOLT(LR_MUX1_BAT_THERM, 0) > VADC_CHAN_VOLT(LR_MUX2_BAT_ID, 0) > VADC_CHAN_VOLT(LR_MUX3_XO_THERM, 0) >@@ -690,42 +861,40 @@ struct vadc_channels { > VADC_CHAN_VOLT(AMUX_PU1, 0) > VADC_CHAN_VOLT(AMUX_PU2, 0) > VADC_CHAN_VOLT(LR_MUX3_BUF_XO_THERM, 0) >- >- VADC_CHAN_VOLT(LR_MUX1_PU1_BAT_THERM, 0) >+ VADC_CHAN_TEMP(LR_MUX1_PU1_BAT_THERM, 0) > VADC_CHAN_VOLT(LR_MUX2_PU1_BAT_ID, 0) >- VADC_CHAN_VOLT(LR_MUX3_PU1_XO_THERM, 0) >- VADC_CHAN_VOLT(LR_MUX4_PU1_AMUX_THM1, 0) >- VADC_CHAN_VOLT(LR_MUX5_PU1_AMUX_THM2, 0) >- VADC_CHAN_VOLT(LR_MUX6_PU1_AMUX_THM3, 0) >+ VADC_CHAN_TEMP(LR_MUX3_PU1_XO_THERM, 0) >+ VADC_CHAN_TEMP(LR_MUX4_PU1_AMUX_THM1, 0) >+ VADC_CHAN_TEMP(LR_MUX5_PU1_AMUX_THM2, 0) >+ VADC_CHAN_TEMP(LR_MUX6_PU1_AMUX_THM3, 0) > VADC_CHAN_VOLT(LR_MUX7_PU1_AMUX_HW_ID, 0) >- VADC_CHAN_VOLT(LR_MUX8_PU1_AMUX_THM4, 0) >- VADC_CHAN_VOLT(LR_MUX9_PU1_AMUX_THM5, 0) >+ VADC_CHAN_TEMP(LR_MUX8_PU1_AMUX_THM4, 0) >+ VADC_CHAN_TEMP(LR_MUX9_PU1_AMUX_THM5, 0) > VADC_CHAN_VOLT(LR_MUX10_PU1_AMUX_USB_ID, 0) >- VADC_CHAN_VOLT(LR_MUX3_BUF_PU1_XO_THERM, 0) >- >- VADC_CHAN_VOLT(LR_MUX1_PU2_BAT_THERM, 0) >+ VADC_CHAN_TEMP(LR_MUX3_BUF_PU1_XO_THERM, 0) >+ VADC_CHAN_TEMP(LR_MUX1_PU2_BAT_THERM, 0) > VADC_CHAN_VOLT(LR_MUX2_PU2_BAT_ID, 0) >- VADC_CHAN_VOLT(LR_MUX3_PU2_XO_THERM, 0) >- VADC_CHAN_VOLT(LR_MUX4_PU2_AMUX_THM1, 0) >- VADC_CHAN_VOLT(LR_MUX5_PU2_AMUX_THM2, 0) >- VADC_CHAN_VOLT(LR_MUX6_PU2_AMUX_THM3, 0) >+ VADC_CHAN_TEMP(LR_MUX3_PU2_XO_THERM, 0) >+ VADC_CHAN_TEMP(LR_MUX4_PU2_AMUX_THM1, 0) >+ VADC_CHAN_TEMP(LR_MUX5_PU2_AMUX_THM2, 0) >+ VADC_CHAN_TEMP(LR_MUX6_PU2_AMUX_THM3, 0) > VADC_CHAN_VOLT(LR_MUX7_PU2_AMUX_HW_ID, 0) >- VADC_CHAN_VOLT(LR_MUX8_PU2_AMUX_THM4, 0) >- VADC_CHAN_VOLT(LR_MUX9_PU2_AMUX_THM5, 0) >+ VADC_CHAN_TEMP(LR_MUX8_PU2_AMUX_THM4, 0) >+ VADC_CHAN_TEMP(LR_MUX9_PU2_AMUX_THM5, 0) > VADC_CHAN_VOLT(LR_MUX10_PU2_AMUX_USB_ID, 0) >- VADC_CHAN_VOLT(LR_MUX3_BUF_PU2_XO_THERM, 0) >- >- VADC_CHAN_VOLT(LR_MUX1_PU1_PU2_BAT_THERM, 0) >+ VADC_CHAN_TEMP(LR_MUX3_BUF_PU2_XO_THERM, 0) >+ VADC_CHAN_TEMP(LR_MUX1_PU1_PU2_BAT_THERM, 0) > VADC_CHAN_VOLT(LR_MUX2_PU1_PU2_BAT_ID, 0) >- VADC_CHAN_VOLT(LR_MUX3_PU1_PU2_XO_THERM, 0) >- VADC_CHAN_VOLT(LR_MUX4_PU1_PU2_AMUX_THM1, 0) >- VADC_CHAN_VOLT(LR_MUX5_PU1_PU2_AMUX_THM2, 0) >- VADC_CHAN_VOLT(LR_MUX6_PU1_PU2_AMUX_THM3, 0) >+ VADC_CHAN_TEMP(LR_MUX3_PU1_PU2_XO_THERM, 0) >+ VADC_CHAN_TEMP(LR_MUX4_PU1_PU2_AMUX_THM1, 0) >+ VADC_CHAN_TEMP(LR_MUX5_PU1_PU2_AMUX_THM2, 0) >+ VADC_CHAN_TEMP(LR_MUX6_PU1_PU2_AMUX_THM3, 0) > VADC_CHAN_VOLT(LR_MUX7_PU1_PU2_AMUX_HW_ID, 0) >- VADC_CHAN_VOLT(LR_MUX8_PU1_PU2_AMUX_THM4, 0) >- VADC_CHAN_VOLT(LR_MUX9_PU1_PU2_AMUX_THM5, 0) >+ VADC_CHAN_TEMP(LR_MUX8_PU1_PU2_AMUX_THM4, 0) >+ VADC_CHAN_TEMP(LR_MUX9_PU1_PU2_AMUX_THM5, 0) > VADC_CHAN_VOLT(LR_MUX10_PU1_PU2_AMUX_USB_ID, 0) >- VADC_CHAN_VOLT(LR_MUX3_BUF_PU1_PU2_XO_THERM, 0) >+ VADC_CHAN_TEMP(LR_MUX3_BUF_PU1_PU2_XO_THERM, 0) >+ > }; > > static int vadc_get_dt_channel_data(struct device *dev, >@@ -802,6 +971,11 @@ static int vadc_get_dt_channel_data(struct device *dev, > prop->avg_samples = VADC_DEF_AVG_SAMPLES; > } > >+ ret = of_property_read_u32(node, "qcom,scale-function", >+ &prop->scale_function); >+ if (ret) >+ prop->scale_function = SCALE_DEFAULT; >+ Is this a new binding, in that case the documentation has to be updated for this and probably introduce this in one first patch and more patches for the rest of the changes. > if (of_property_read_bool(node, "qcom,ratiometric")) > prop->calibration = VADC_CALIB_RATIOMETRIC; > else >@@ -850,9 +1024,9 @@ static int vadc_get_dt_data(struct vadc_priv *vadc, struct device_node *node) > > iio_chan->channel = prop.channel; > iio_chan->datasheet_name = vadc_chan->datasheet_name; >+ iio_chan->extend_name = child->name; > iio_chan->info_mask_separate = vadc_chan->info_mask; > iio_chan->type = vadc_chan->type; >- iio_chan->indexed = 1; > iio_chan->address = index++; > > iio_chan++; >@@ -964,16 +1138,21 @@ static int vadc_probe(struct platform_device *pdev) > if (ret) > return ret; > >- irq_eoc = platform_get_irq(pdev, 0); >- if (irq_eoc < 0) { >- if (irq_eoc == -EPROBE_DEFER || irq_eoc == -EINVAL) >- return irq_eoc; >- vadc->poll_eoc = true; >- } else { >- ret = devm_request_irq(dev, irq_eoc, vadc_isr, 0, >- "spmi-vadc", vadc); >- if (ret) >- return ret; >+ vadc->poll_eoc = of_property_read_bool(node, >+ "qcom,vadc-poll-eoc"); >+ Same comment as above for introducing the new binding and the reason for that. >+ if (!vadc->poll_eoc) { >+ irq_eoc = platform_get_irq(pdev, 0); >+ if (irq_eoc < 0) { >+ if (irq_eoc == -EPROBE_DEFER || irq_eoc == -EINVAL) >+ return irq_eoc; >+ vadc->poll_eoc = true; >+ } else { >+ ret = devm_request_irq(dev, irq_eoc, vadc_isr, 0, >+ "spmi-vadc", vadc); >+ if (ret) >+ return ret; >+ } > } > > ret = vadc_reset(vadc); Regards, Sricharan -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html