Commit 3bd0ceb5 authored by Dmitry Baryshkov's avatar Dmitry Baryshkov Committed by Jonathan Cameron
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iio: adc: qcom-vadc-common: rewrite vadc7 die temp calculation 



qcom_vadc7_scale_hw_calib_die_temp() uses a table format different from
the rest of volt/temp conversion functions in this file. Also the
conversion functions results in non-monothonic values conversion, which
seems wrong.

Rewrite qcom_vadc7_scale_hw_calib_die_temp() to use
qcom_vadc_map_voltage_temp() directly, like the rest of conversion
functions do.

Signed-off-by: default avatarDmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20201204025509.1075506-10-dmitry.baryshkov@linaro.org


Signed-off-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
parent bb01e263

drivers/iio/adc/qcom-vadc-common.c

+15 −35
Original line number Diff line number Diff line
@@ -101,18 +101,18 @@ static const struct vadc_map_pt adcmap_100k_104ef_104fb_1875_vref[] = { 
};



static const struct vadc_map_pt adcmap7_die_temp[] = {

	{ 433700, 1967},

	{ 473100, 1964},

	{ 512400, 1957},

	{ 551500, 1949},

	{ 590500, 1940},

	{ 629300, 1930},

	{ 667900, 1921},

	{ 706400, 1910},

	{ 744600, 1896},

	{ 782500, 1878},

	{ 820100, 1859},

	{ 857300, 0},

	{ 857300, 160000 },

	{ 820100, 140000 },

	{ 782500, 120000 },

	{ 744600, 100000 },

	{ 706400, 80000 },

	{ 667900, 60000 },

	{ 629300, 40000 },

	{ 590500, 20000 },

	{ 551500, 0 },

	{ 512400, -20000 },

	{ 473100, -40000 },

	{ 433700, -60000 },

};



/*
@@ -585,33 +585,13 @@ static int qcom_vadc7_scale_hw_calib_die_temp( 
				u16 adc_code, int *result_mdec)

{



	int voltage, vtemp0, temp, i;

	int voltage;



	voltage = qcom_vadc_scale_code_voltage_factor(adc_code,

				prescale, data, 1);



	if (adcmap7_die_temp[0].x > voltage) {

		*result_mdec = DIE_TEMP_ADC7_SCALE_1;

		return 0;

	}



	if (adcmap7_die_temp[ARRAY_SIZE(adcmap7_die_temp) - 1].x <= voltage) {

		*result_mdec = DIE_TEMP_ADC7_MAX;

		return 0;

	}



	for (i = 0; i < ARRAY_SIZE(adcmap7_die_temp); i++)

		if (adcmap7_die_temp[i].x > voltage)

			break;



	vtemp0 = adcmap7_die_temp[i - 1].x;

	voltage = voltage - vtemp0;

	temp = div64_s64(voltage * DIE_TEMP_ADC7_SCALE_FACTOR,

		adcmap7_die_temp[i - 1].y);

	temp += DIE_TEMP_ADC7_SCALE_1 + (DIE_TEMP_ADC7_SCALE_2 * (i - 1));

	*result_mdec = temp;



	return 0;

	return qcom_vadc_map_voltage_temp(adcmap7_die_temp, ARRAY_SIZE(adcmap7_die_temp),

			voltage, result_mdec);

}



static int qcom_vadc_scale_hw_smb_temp(

include/linux/iio/adc/qcom-vadc-common.h

+0 −5
Original line number Diff line number Diff line
@@ -54,11 +54,6 @@ 
#define R_PU_100K				100000

#define RATIO_MAX_ADC7				BIT(14)



#define DIE_TEMP_ADC7_SCALE_1			-60000

#define DIE_TEMP_ADC7_SCALE_2			20000

#define DIE_TEMP_ADC7_SCALE_FACTOR		1000

#define DIE_TEMP_ADC7_MAX			160000



/*

 * VADC_CALIB_ABSOLUTE: uses the 625mV and 1.25V as reference channels.

 * VADC_CALIB_RATIOMETRIC: uses the reference voltage (1.8V) and GND for