Add changes to support different scale functions to convert adc code to
physical units.
Signed-off-by: Rama Krishna Phani A <rphani@xxxxxxxxxxxxxx>
---
.../devicetree/bindings/iio/adc/qcom,spmi-vadc.txt | 14 ++
drivers/iio/adc/qcom-spmi-vadc.c | 263 +++++++++++++++++----
2 files changed, 236 insertions(+), 41 deletions(-)
diff --git a/Documentation/devicetree/bindings/iio/adc/qcom,spmi-vadc.txt b/Documentation/devicetree/bindings/iio/adc/qcom,spmi-vadc.txt
index 0fb4613..39e31c0e 100644
--- a/Documentation/devicetree/bindings/iio/adc/qcom,spmi-vadc.txt
+++ b/Documentation/devicetree/bindings/iio/adc/qcom,spmi-vadc.txt
@@ -37,6 +37,12 @@ VADC node:
Value type: <prop-encoded-array>
Definition: End of conversion interrupt.
+- qcom,vadc-poll-eoc:
+ Usage: optional
+ Value type: <bool>
+ Definition: Use polling instead of interrupts for End of Conversion
+ completion.
+
Channel node properties:
- reg:
@@ -92,6 +98,14 @@ Channel node properties:
Valid values are: 1, 2, 4, 8, 16, 32, 64, 128, 256, 512
If property is not found, 1 sample will be used.
+- qcom,scale-function:
+ Usage: optional
+ Value type: <u32>
+ Definition: Scaling function used to convert raw ADC code to
+ units specific to a given channel. Scaled units can be
+ microvolts, millidegC.Valid values are: 0, 1, 2, 3, 4.
+ If property is not found, 0 scaling will be used.
+
NOTE:
Following channels, also known as reference point channels, are used for
diff --git a/drivers/iio/adc/qcom-spmi-vadc.c b/drivers/iio/adc/qcom-spmi-vadc.c
index ff4d549..6e521a9 100644
--- a/drivers/iio/adc/qcom-spmi-vadc.c
+++ b/drivers/iio/adc/qcom-spmi-vadc.c
@@ -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);
@@ -468,6 +546,51 @@ static int vadc_measure_ref_points(struct vadc_priv *vadc)
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)
@@ -489,15 +612,61 @@ 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;
+ s64 voltage = 0, result = 0;
+ int ret;
+
+ switch (prop->scale_function) {
+ 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);
+
+ case SCALE_THERM_100K_PULLUP:
+ case SCALE_XOTHERM:
+ vadc_scale_calib(vadc, adc_code, prop, &voltage);
+
+ if (prop->calibration == VADC_CALIB_ABSOLUTE)
+ 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;
+ voltage /= (prescale->num * 2);
+ } else {
+ voltage = 0;
+ }
+
+ voltage -= KELVINMIL_CELSIUSMIL;
- vadc_scale_calib(vadc, adc_code, prop, &voltage);
+ return voltage;
- prescale = &vadc_prescale_ratios[prop->prescale];
+ case SCALE_PMI_CHG_TEMP:
+ vadc_scale_calib(vadc, adc_code, prop, &voltage);
+ prescale = &vadc_prescale_ratios[prop->prescale];
+ voltage = voltage * prescale->den;
- 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);
- return div64_s64(voltage, prescale->num);
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ return ret;
}
static int vadc_decimation_from_dt(u32 value)
@@ -615,7 +784,9 @@ 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, \
@@ -639,7 +810,7 @@ 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)
@@ -693,41 +864,41 @@ struct vadc_channels {
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_TEMP(LR_MUX3_BUF_PU1_XO_THERM, 0)
- VADC_CHAN_VOLT(LR_MUX1_PU2_BAT_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_TEMP(LR_MUX3_BUF_PU2_XO_THERM, 0)
- VADC_CHAN_VOLT(LR_MUX1_PU1_PU2_BAT_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,
@@ -804,6 +975,11 @@ 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;
+
if (of_property_read_bool(node, "qcom,ratiometric"))
prop->calibration = VADC_CALIB_RATIOMETRIC;
else
@@ -966,16 +1142,21 @@ 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");
+
+ 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);
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project
--
To unsubscribe from this list: send the line "unsubscribe linux-iio" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
