Re: [PATCH v9 12/15] thermal: qcom: add support for adc-tm5 PMIC thermal monitor

[Dmitry Baryshkov <dmitry.baryshkov@linaro.org>]

On 19/11/2020 18:33, Daniel Lezcano wrote:
> On 02/11/2020 18:49, Dmitry Baryshkov wrote:
>> Add support for Thermal Monitoring part of PMIC5. This part is closely
>> coupled with ADC, using it's channels directly. ADC-TM support
>> generating interrupts on ADC value crossing low or high voltage bounds,
>> which is used to support thermal trip points.
> 
> Please, document the driver, so the review will be easier.
> 
> Some comments in the code would help also.

OK, I'll try.

> 
> 
>> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
>> ---
>>   drivers/iio/adc/qcom-vadc-common.c       |  44 ++
>>   drivers/thermal/qcom/Kconfig             |  11 +
>>   drivers/thermal/qcom/Makefile            |   1 +
>>   drivers/thermal/qcom/qcom-spmi-adc-tm5.c | 604 +++++++++++++++++++++++
>>   include/linux/iio/adc/qcom-vadc-common.h |   3 +
>>   5 files changed, 663 insertions(+)
>>   create mode 100644 drivers/thermal/qcom/qcom-spmi-adc-tm5.c
>>
>> diff --git a/drivers/iio/adc/qcom-vadc-common.c b/drivers/iio/adc/qcom-vadc-common.c
>> index 8682cf1e213f..da2f2afc26ee 100644
>> --- a/drivers/iio/adc/qcom-vadc-common.c
>> +++ b/drivers/iio/adc/qcom-vadc-common.c
>> @@ -368,6 +368,23 @@ static int qcom_vadc_map_voltage_temp(const struct vadc_map_pt *pts,
>>   	return 0;
>>   }
>>   
>> +static s32 qcom_vadc_map_temp_voltage(const struct vadc_map_pt *pts,
>> +				      u32 tablesize, int input)
>> +{
>> +	u32 i = 0;
>> +
>> +	while (i < tablesize && pts[i].y < input)
>> +		i++;
>> +
> 
> Comment

Find the first entry that is greater than the temp provided?

> 
>> +	if (i == 0)
>> +		return pts[0].x;
>> +	if (i == tablesize)
>> +		return pts[tablesize - 1].x;
>> +
>> +	return fixp_linear_interpolate(pts[i - 1].y, pts[i - 1].x,
>> +			pts[i].y, pts[i].x, input);
>> +}
>>   static void qcom_vadc_scale_calib(const struct vadc_linear_graph *calib_graph,
>>   				  u16 adc_code,
>>   				  bool absolute,
>> @@ -463,6 +480,20 @@ static int qcom_vadc_scale_chg_temp(const struct vadc_linear_graph *calib_graph,
>>   	return 0;
>>   }
>>   
>> +static u16 qcom_vadc_scale_voltage_code(int voltage,
>> +					const struct vadc_prescale_ratio *prescale,
>> +					const u32 full_scale_code_volt,
>> +					unsigned int factor)
>> +{
>> +	s64 volt = voltage;
>> +	s64 adc_vdd_ref_mv = 1875;
> 
> Comment to explain

1.875V is an ADC reference voltage.

> 
>> +	volt *= prescale->num * factor * full_scale_code_volt;
>> +	volt = div64_s64(volt, (s64)prescale->den * adc_vdd_ref_mv * 1000);
>> +	return volt;
>> +}
> 
> The function returns u16 but  volt is s64.

The function returns the value to be programmed into comparator.

> 
>> +
>>   static int qcom_vadc_scale_code_voltage_factor(u16 adc_code,
>>   				const struct vadc_prescale_ratio *prescale,
>>   				const struct adc5_data *data,
>> @@ -627,6 +658,19 @@ int qcom_vadc_scale(enum vadc_scale_fn_type scaletype,
>>   }
>>   EXPORT_SYMBOL(qcom_vadc_scale);
>>   
>> +u16 qcom_adc_tm5_temp_volt_scale(unsigned int prescale_ratio,
>> +				 u32 full_scale_code_volt, int temp)
>> +{
>> +	const struct vadc_prescale_ratio *prescale = &adc5_prescale_ratios[prescale_ratio];
>> +	s32 voltage;
>> +
>> +	voltage = qcom_vadc_map_temp_voltage(adcmap_100k_104ef_104fb_1875_vref,
>> +					     ARRAY_SIZE(adcmap_100k_104ef_104fb_1875_vref),
>> +					     temp);
> 
> voltage is s32, parameter is int below.

I'll fix this.

> 
>> +	return qcom_vadc_scale_voltage_code(voltage, prescale, full_scale_code_volt, 1000);
>> +}
>> +EXPORT_SYMBOL(qcom_adc_tm5_temp_volt_scale);
>> +
>>   int qcom_adc5_hw_scale(enum vadc_scale_fn_type scaletype,
>>   		    unsigned int prescale_ratio,
>>   		    const struct adc5_data *data,
>> diff --git a/drivers/thermal/qcom/Kconfig b/drivers/thermal/qcom/Kconfig
>> index aa9c1d80fae4..8d5ac2df26dc 100644
>> --- a/drivers/thermal/qcom/Kconfig
>> +++ b/drivers/thermal/qcom/Kconfig
>> @@ -10,6 +10,17 @@ config QCOM_TSENS
>>   	  Also able to set threshold temperature for both hot and cold and update
>>   	  when a threshold is reached.
>>   
>> +config QCOM_SPMI_ADC_TM5
>> +	tristate "Qualcomm SPMI PMIC Thermal Monitor ADC5"
>> +	depends on OF && SPMI && IIO
>> +	select REGMAP_SPMI
>> +	select QCOM_VADC_COMMON
>> +	help
>> +	  This enables the thermal driver for the ADC thermal monitoring
>> +	  device. It shows up as a thermal zone with multiple trip points.
>> +	  Thermal client sets threshold temperature for both warm and cool and
>> +	  gets updated when a threshold is reached.
>> +
>>   config QCOM_SPMI_TEMP_ALARM
>>   	tristate "Qualcomm SPMI PMIC Temperature Alarm"
>>   	depends on OF && SPMI && IIO
>> diff --git a/drivers/thermal/qcom/Makefile b/drivers/thermal/qcom/Makefile
>> index ec86eef7f6a6..252ea7d9da0b 100644
>> --- a/drivers/thermal/qcom/Makefile
>> +++ b/drivers/thermal/qcom/Makefile
>> @@ -3,4 +3,5 @@ obj-$(CONFIG_QCOM_TSENS)	+= qcom_tsens.o
>>   
>>   qcom_tsens-y			+= tsens.o tsens-v2.o tsens-v1.o tsens-v0_1.o \
>>   				   tsens-8960.o
>> +obj-$(CONFIG_QCOM_SPMI_ADC_TM5)	+= qcom-spmi-adc-tm5.o
>>   obj-$(CONFIG_QCOM_SPMI_TEMP_ALARM)	+= qcom-spmi-temp-alarm.o
>> diff --git a/drivers/thermal/qcom/qcom-spmi-adc-tm5.c b/drivers/thermal/qcom/qcom-spmi-adc-tm5.c
>> new file mode 100644
>> index 000000000000..eda3f2d1697e
>> --- /dev/null
>> +++ b/drivers/thermal/qcom/qcom-spmi-adc-tm5.c
>> @@ -0,0 +1,604 @@
>> +// SPDX-License-Identifier: GPL-2.0-only
>> +/*
>> + * Copyright (c) 2012-2020, The Linux Foundation. All rights reserved.
> 
> Why adding the copyright above ?

LF (CAF) is the author of original code, heavily reworked by me.

> 
>> + * Copyright (c) 2020 Linaro Limited
>> + */
>> +
>> +#include <linux/bitfield.h>
>> +#include <linux/iio/adc/qcom-vadc-common.h>
>> +#include <linux/iio/consumer.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/module.h>
>> +#include <linux/of.h>
>> +#include <linux/of_device.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/regmap.h>
>> +#include <linux/thermal.h>
>> +
>> +#define ADC5_MAX_CHANNEL                        0xc0
>> +#define ADC_TM5_NUM_CHANNELS		8
>> +
>> +#define ADC_TM5_STATUS_LOW			0x0a
>> +
>> +#define ADC_TM5_STATUS_HIGH			0x0b
>> +
>> +#define ADC_TM5_NUM_BTM				0x0f
>> +
>> +#define ADC_TM5_ADC_DIG_PARAM			0x42
>> +
>> +#define ADC_TM5_FAST_AVG_CTL			(ADC_TM5_ADC_DIG_PARAM + 1)
>> +#define ADC_TM5_FAST_AVG_EN				BIT(7)
>> +
>> +#define ADC_TM5_MEAS_INTERVAL_CTL		(ADC_TM5_ADC_DIG_PARAM + 2)
>> +#define ADC_TM5_TIMER1					3 /* 3.9ms */
>> +
>> +#define ADC_TM5_MEAS_INTERVAL_CTL2		(ADC_TM5_ADC_DIG_PARAM + 3)
>> +#define ADC_TM5_MEAS_INTERVAL_CTL2_MASK			0xf0
>> +#define ADC_TM5_TIMER2					10 /* 1 second */
>> +#define ADC_TM5_MEAS_INTERVAL_CTL3_MASK			0xf
>> +#define ADC_TM5_TIMER3					4 /* 4 second */
> 
> Should it be 40 ?

Verifyed register description. No, these values are correct.

> 
> 
>> +#define ADC_TM_EN_CTL1				0x46
>> +#define ADC_TM_EN					BIT(7)
>> +#define ADC_TM_CONV_REQ				0x47
>> +#define ADC_TM_CONV_REQ_EN				BIT(7)
>> +
>> +#define ADC_TM5_M_CHAN_BASE			0x60
>> +
>> +#define ADC_TM5_M_ADC_CH_SEL_CTL(n)		(ADC_TM5_M_CHAN_BASE + ((n) * 8) + 0)
>> +#define ADC_TM5_M_LOW_THR0(n)			(ADC_TM5_M_CHAN_BASE + ((n) * 8) + 1)
>> +#define ADC_TM5_M_LOW_THR1(n)			(ADC_TM5_M_CHAN_BASE + ((n) * 8) + 2)
>> +#define ADC_TM5_M_HIGH_THR0(n)			(ADC_TM5_M_CHAN_BASE + ((n) * 8) + 3)
>> +#define ADC_TM5_M_HIGH_THR1(n)			(ADC_TM5_M_CHAN_BASE + ((n) * 8) + 4)
>> +#define ADC_TM5_M_MEAS_INTERVAL_CTL(n)		(ADC_TM5_M_CHAN_BASE + ((n) * 8) + 5)
>> +#define ADC_TM5_M_CTL(n)			(ADC_TM5_M_CHAN_BASE + ((n) * 8) + 6)
>> +#define ADC_TM5_M_CTL_HW_SETTLE_DELAY_MASK		0xf
>> +#define ADC_TM5_M_CTL_CAL_SEL_MASK			0x30
>> +#define ADC_TM5_M_CTL_CAL_VAL				0x40
>> +#define ADC_TM5_M_EN(n)				(ADC_TM5_M_CHAN_BASE + ((n) * 8) + 7)
>> +#define ADC_TM5_M_MEAS_EN				BIT(7)
>> +#define ADC_TM5_M_HIGH_THR_INT_EN			BIT(1)
>> +#define ADC_TM5_M_LOW_THR_INT_EN			BIT(0)
>> +
>> +enum adc5_timer_select {
>> +	ADC5_TIMER_SEL_1 = 0,
>> +	ADC5_TIMER_SEL_2,
>> +	ADC5_TIMER_SEL_3,
>> +	ADC5_TIMER_SEL_NONE,
>> +};
>> +
>> +struct adc_tm5_data {
>> +	const u32	full_scale_code_volt;
>> +	unsigned int	*decimation;
>> +	unsigned int	*hw_settle;
>> +};
>> +
>> +enum adc_tm5_cal_method {
>> +	ADC_TM5_NO_CAL = 0,
>> +	ADC_TM5_RATIOMETRIC_CAL,
>> +	ADC_TM5_ABSOLUTE_CAL
>> +};
>> +
>> +struct adc_tm5_chip;
>> +
>> +/**
>> + * struct adc_tm5_channel - ADC Thermal Monitoring channel data.
>> + * @channel: channel number.
>> + * @adc_channel: corresponding ADC channel number.
>> + * @cal_method: calibration method.
>> + * @prescale: channel scaling performed on the input signal.
>> + * @hw_settle_time: the time between AMUX being configured and the
>> + *	start of conversion.
>> + * @iio: IIO channel instance used by this channel.
>> + * @chip: ADC TM chip instance.
>> + * @tzd: thermal zone device used by this channel.
>> + */
>> +struct adc_tm5_channel {
>> +	unsigned int		channel;
>> +	unsigned int		adc_channel;
>> +	enum adc_tm5_cal_method	cal_method;
>> +	unsigned int		prescale;
>> +	unsigned int		hw_settle_time;
>> +	struct iio_channel	*iio;
>> +	struct adc_tm5_chip	*chip;
>> +	struct thermal_zone_device *tzd;
>> +};
>> +
>> +/**
>> + * struct adc_tm5_chip - ADC Thermal Monitoring properties
>> + * @regmap: SPMI ADC5 Thermal Monitoring  peripheral register map field.
>> + * @dev: SPMI ADC5 device.
>> + * @data: software configuration data.
>> + * @channels: array of ADC TM channel data.
>> + * @nchannels: amount of channels defined/allocated
>> + * @decimation: sampling rate supported for the channel.
>> + * @avg_samples: ability to provide single result from the ADC
>> + *	that is an average of multiple measurements.
>> + * @base: base address of TM registers.
>> + */
>> +struct adc_tm5_chip {
>> +	struct regmap		*regmap;
>> +	struct device		*dev;
>> +	const struct adc_tm5_data	*data;
>> +	struct adc_tm5_channel	*channels;
>> +	unsigned int		nchannels;
>> +	unsigned int		decimation;
>> +	unsigned int		avg_samples;
>> +	u16			base;
>> +};
>> +
>> +static const struct adc_tm5_data adc_tm5_data_pmic = {
>> +	.full_scale_code_volt = 0x70e4,
>> +	.decimation = (unsigned int []) { 250, 420, 840 },
>> +	.hw_settle = (unsigned int []) { 15, 100, 200, 300, 400, 500, 600, 700,
>> +					 1000, 2000, 4000, 8000, 16000, 32000,
>> +					 64000, 128000 },
>> +};
>> +
>> +static int adc_tm5_read(struct adc_tm5_chip *adc_tm, u16 offset, u8 *data, int len)
>> +{
>> +	return regmap_bulk_read(adc_tm->regmap, adc_tm->base + offset, data, len);
>> +}
>> +
>> +static int adc_tm5_write(struct adc_tm5_chip *adc_tm, u16 offset, u8 *data, int len)
>> +{
>> +	return regmap_bulk_write(adc_tm->regmap, adc_tm->base + offset, data, len);
>> +}
>> +
>> +static int adc_tm5_reg_update(struct adc_tm5_chip *adc_tm, u16 offset, u8 mask, u8 val)
>> +{
>> +	return regmap_write_bits(adc_tm->regmap, adc_tm->base + offset, mask, val);
>> +}
>> +
>> +static irqreturn_t adc_tm5_isr(int irq, void *data)
>> +{
>> +	struct adc_tm5_chip *chip = data;
>> +	u8 status_low, status_high, ctl;
>> +	int ret, i;
>> +
>> +	ret = adc_tm5_read(chip, ADC_TM5_STATUS_LOW, &status_low, sizeof(status_low));
>> +	if (unlikely(ret)) {
>> +		dev_err(chip->dev, "read status low failed: %d\n", ret);
>> +		return IRQ_HANDLED;
>> +	}
> 
> I suspect there is a deadlock here. If any routine calling adc_tm5_read
> / adc_tm5_write which holds the regmap lock is interrupted by this isr,
> it will try to acquire the lock again and block.

isr is a threaded IRQ, so it won't deadlock here.

> 
>> +	ret = adc_tm5_read(chip, ADC_TM5_STATUS_HIGH, &status_high, sizeof(status_high));
>> +	if (unlikely(ret)) {
>> +		dev_err(chip->dev, "read status high failed: %d\n", ret);
>> +		return IRQ_HANDLED;
>> +	}
>> +
>> +	for (i = 0; i < chip->nchannels; i++) {
>> +		bool upper_set = false, lower_set = false;
>> +		unsigned int ch = chip->channels[i].channel;
>> +
>> +		/* No TZD, we warned at the boot time */
>> +		if (!chip->channels[i].tzd)
>> +			continue;
>> +
>> +		ret = adc_tm5_read(chip, ADC_TM5_M_EN(ch), &ctl, sizeof(ctl));
>> +		if (unlikely(ret)) {
>> +			dev_err(chip->dev, "ctl read failed: %d, channel %d\n", ret, i);
>> +			continue;
>> +		}
>> +
>> +		if (!(ctl & ADC_TM5_M_MEAS_EN))
>> +			continue;
>> +
>> +		lower_set = (status_low & BIT(ch)) &&
>> +			(ctl & ADC_TM5_M_LOW_THR_INT_EN);
>> +
>> +		upper_set = (status_high & BIT(ch)) &&
>> +			(ctl & ADC_TM5_M_HIGH_THR_INT_EN);
>> +
>> +		if (upper_set || lower_set)
>> +			thermal_zone_device_update(chip->channels[i].tzd,
>> +						   THERMAL_EVENT_UNSPECIFIED);
>> +	}
>> +
>> +	return IRQ_HANDLED;
>> +}
>> +
>> +static int adc_tm5_get_temp(void *data, int *temp)
>> +{
>> +	struct adc_tm5_channel *channel = data;
>> +
>> +	if (!channel || !channel->iio)
>> +		return -EINVAL;
>> +
>> +	return iio_read_channel_processed(channel->iio, temp);
>> +}
>> +
>> +static int adc_tm5_disable_channel(struct adc_tm5_channel *channel)
>> +{
>> +	struct adc_tm5_chip *chip = channel->chip;
>> +	unsigned int reg = ADC_TM5_M_EN(channel->channel);
>> +
>> +	return adc_tm5_reg_update(chip, reg,
>> +				  ADC_TM5_M_MEAS_EN |
>> +				  ADC_TM5_M_HIGH_THR_INT_EN |
>> +				  ADC_TM5_M_LOW_THR_INT_EN,
>> +				  0);
>> +}
>> +
>> +static int adc_tm5_enable(struct adc_tm5_chip *chip)
>> +{
>> +	int ret;
>> +	u8 data;
>> +
>> +	data = ADC_TM_EN;
>> +	ret = adc_tm5_write(chip, ADC_TM_EN_CTL1, &data, sizeof(data));
>> +	if (ret < 0) {
>> +		dev_err(chip->dev, "adc-tm enable failed\n");
>> +		return ret;
>> +	}
>> +
>> +	data = ADC_TM_CONV_REQ_EN;
>> +	ret = adc_tm5_write(chip, ADC_TM_CONV_REQ, &data, sizeof(data));
>> +	if (ret < 0) {
>> +		dev_err(chip->dev, "adc-tm request conversion failed\n");
>> +		return ret;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int adc_tm5_configure(struct adc_tm5_channel *channel, int low, int high)
>> +{
>> +	struct adc_tm5_chip *chip = channel->chip;
>> +	u8 buf[8];
>> +	u16 reg = ADC_TM5_M_ADC_CH_SEL_CTL(channel->channel);
>> +	int ret;
>> +
>> +	ret = adc_tm5_read(chip, reg, buf, sizeof(buf));
>> +	if (ret) {
>> +		dev_err(chip->dev, "channel %d params read failed: %d\n", channel->channel, ret);
>> +		return ret;
>> +	}
>> +
>> +	buf[0] = channel->adc_channel;
>> +
>> +	/* High temperature corresponds to low voltage threshold */
>> +	if (high != INT_MAX) {
>> +		u16 adc_code = qcom_adc_tm5_temp_volt_scale(channel->prescale,
>> +				chip->data->full_scale_code_volt, high);
>> +
>> +		buf[1] = adc_code & 0xff;
>> +		buf[2] = adc_code >> 8;
>> +		buf[7] |= ADC_TM5_M_LOW_THR_INT_EN;
>> +	} else {
>> +		buf[7] &= ~ADC_TM5_M_LOW_THR_INT_EN;
>> +	}
>> +
>> +	/* Low temperature corresponds to high voltage threshold */
>> +	if (low != -INT_MAX) {
>> +		u16 adc_code = qcom_adc_tm5_temp_volt_scale(channel->prescale,
>> +				chip->data->full_scale_code_volt, low);
>> +
>> +		buf[3] = adc_code & 0xff;
>> +		buf[4] = adc_code >> 8;
>> +		buf[7] |= ADC_TM5_M_HIGH_THR_INT_EN;
>> +	} else {
>> +		buf[7] &= ~ADC_TM5_M_HIGH_THR_INT_EN;
>> +	}
>> +
>> +	buf[5] = ADC5_TIMER_SEL_2;
>> +
>> +	/* Set calibration select, hw_settle delay */
>> +	buf[6] &= ~ADC_TM5_M_CTL_HW_SETTLE_DELAY_MASK;
>> +	buf[6] |= FIELD_PREP(ADC_TM5_M_CTL_HW_SETTLE_DELAY_MASK, channel->hw_settle_time);
>> +	buf[6] &= ~ADC_TM5_M_CTL_CAL_SEL_MASK;
>> +	buf[6] |= FIELD_PREP(ADC_TM5_M_CTL_CAL_SEL_MASK, channel->cal_method);
>> +
>> +	buf[7] |= ADC_TM5_M_MEAS_EN;
>> +
>> +	ret = adc_tm5_write(chip, reg, buf, sizeof(buf));
>> +	if (ret) {
>> +		dev_err(chip->dev, "channel %d params write failed: %d\n", channel->channel, ret);
>> +		return ret;
>> +	}
>> +
>> +	return adc_tm5_enable(chip);
>> +}
>> +
>> +static int adc_tm5_set_trips(void *data, int low, int high)
>> +{
>> +	struct adc_tm5_channel *channel = data;
>> +	struct adc_tm5_chip *chip;
>> +	int ret;
>> +
>> +	if (!channel)
>> +		return -EINVAL;
>> +
>> +	chip = channel->chip;
>> +	dev_dbg(chip->dev, "%d:low(mdegC):%d, high(mdegC):%d\n",
>> +		channel->channel, low, high);
>> +
>> +	if (high == INT_MAX && low <= -INT_MAX)
>> +		ret = adc_tm5_disable_channel(channel);
>> +	else
>> +		ret = adc_tm5_configure(channel, low, high);
>> +
>> +	return ret;
>> +}
>> +
>> +static struct thermal_zone_of_device_ops adc_tm5_ops = {
>> +	.get_temp = adc_tm5_get_temp,
>> +	.set_trips = adc_tm5_set_trips,
>> +};
>> +
>> +static int adc_tm5_register_tzd(struct adc_tm5_chip *adc_tm)
>> +{
>> +	unsigned int i;
>> +	struct thermal_zone_device *tzd;
>> +
>> +	for (i = 0; i < adc_tm->nchannels; i++) {
>> +		adc_tm->channels[i].chip = adc_tm;
>> +
>> +		tzd = devm_thermal_zone_of_sensor_register(adc_tm->dev,
>> +							   adc_tm->channels[i].channel,
>> +							   &adc_tm->channels[i],
>> +							   &adc_tm5_ops);
>> +		if (IS_ERR(tzd)) {
>> +			dev_err(adc_tm->dev, "Error registering TZ zone for channel %d: %ld\n",
>> +				adc_tm->channels[i].channel, PTR_ERR(tzd));
>> +			return PTR_ERR(tzd);
>> +		}
>> +		adc_tm->channels[i].tzd = tzd;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int adc_tm5_init(struct adc_tm5_chip *chip)
>> +{
>> +	u8 buf[4], channels_available;
>> +	int ret;
>> +	unsigned int i;
>> +
>> +	for (i = 0; i < chip->nchannels; i++) {
>> +		if (chip->channels[i].channel >= channels_available) {
>> +			dev_err(chip->dev, "Invalid channel %d\n", chip->channels[i].channel);
>> +			return -EINVAL;
>> +		}
>> +	}
>> +
>> +	ret = adc_tm5_read(chip, ADC_TM5_NUM_BTM,
>> +			   &channels_available, sizeof(channels_available));
>> +	if (ret) {
>> +		dev_err(chip->dev, "read failed for BTM channels\n");
>> +		return ret;
>> +	}
>> +
>> +	buf[0] = chip->decimation;
>> +	buf[1] = chip->avg_samples | ADC_TM5_FAST_AVG_EN;
>> +	buf[2] = ADC_TM5_TIMER1;
>> +	buf[3] = FIELD_PREP(ADC_TM5_MEAS_INTERVAL_CTL2_MASK, ADC_TM5_TIMER2) |
>> +		 FIELD_PREP(ADC_TM5_MEAS_INTERVAL_CTL3_MASK, ADC_TM5_TIMER3);
>> +
>> +	ret = adc_tm5_write(chip, ADC_TM5_ADC_DIG_PARAM, buf, sizeof(buf));
>> +	if (ret) {
>> +		dev_err(chip->dev, "block write failed: %d\n", ret);
>> +		return ret;
>> +	}
>> +
>> +	return ret;
>> +}
>> +
>> +static int adc_tm5_get_dt_channel_data(struct adc_tm5_chip *adc_tm,
>> +				       struct adc_tm5_channel *channel,
>> +				       struct device_node *node)
>> +{
>> +	const char *name = node->name;
>> +	u32 chan, value, varr[2];
>> +	int ret;
>> +	struct device *dev = adc_tm->dev;
>> +	struct of_phandle_args args;
>> +
>> +	ret = of_property_read_u32(node, "reg", &chan);
>> +	if (ret) {
>> +		dev_err(dev, "%s: invalid channel number %d\n", name, ret);
>> +		return ret;
>> +	}
>> +
>> +	if (chan >= ADC_TM5_NUM_CHANNELS) {
>> +		dev_err(dev, "%s: channel number too big: %d\n", name, chan);
>> +		return -EINVAL;
>> +	}
>> +
>> +	channel->channel = chan;
>> +
>> +	/*
>> +	 * We are tied to PMIC's ADC controller, which always use single
>> +	 * argument for channel number.  So don't bother parsing
>> +	 * #io-channel-cells, just enforce cell_count = 1.
>> +	 */
>> +	ret = of_parse_phandle_with_fixed_args(node, "io-channels", 1, 0, &args);
>> +	if (ret < 0) {
>> +		dev_err(dev, "%s: error parsing ADC channel number %d: %d\n", name, chan, ret);
>> +		return ret;
>> +	}
>> +	of_node_put(args.np);
>> +
>> +	if (args.args_count != 1 || args.args[0] >= ADC5_MAX_CHANNEL) {
>> +		dev_err(dev, "%s: invalid ADC channel number %d\n", name, chan);
>> +		return ret;
>> +	}
>> +	channel->adc_channel = args.args[0];
>> +
>> +	channel->iio = devm_of_iio_channel_get_by_name(adc_tm->dev, node, NULL);
>> +	if (IS_ERR(channel->iio)) {
>> +		ret = PTR_ERR(channel->iio);
>> +		if (ret != -EPROBE_DEFER)
>> +			dev_err(dev, "%s: error getting channel: %d\n", name, ret);
>> +		return ret;
>> +	}
>> +
>> +	ret = of_property_read_u32_array(node, "qcom,pre-scaling", varr, 2);
>> +	if (!ret) {
>> +		ret = qcom_adc5_prescaling_from_dt(varr[0], varr[1]);
>> +		if (ret < 0) {
>> +			dev_err(dev, "%s: invalid pre-scaling <%d %d>\n",
>> +				name, varr[0], varr[1]);
>> +			return ret;
>> +		}
>> +		channel->prescale = ret;
>> +	} else {
>> +		/* 1:1 prescale is index 0 */
>> +		channel->prescale = 0;
>> +	}
>> +
>> +	ret = of_property_read_u32(node, "qcom,hw-settle-time-us", &value);
>> +	if (!ret) {
>> +		ret = qcom_adc5_hw_settle_time_from_dt(value, adc_tm->data->hw_settle);
>> +		if (ret < 0) {
>> +			dev_err(dev, "%s invalid hw-settle-time-us %d us\n",
>> +				name, value);
>> +			return ret;
>> +		}
>> +		channel->hw_settle_time = ret;
>> +	} else {
>> +		channel->hw_settle_time = VADC_DEF_HW_SETTLE_TIME;
>> +	}
>> +
>> +	if (of_property_read_bool(node, "qcom,ratiometric"))
>> +		channel->cal_method = ADC_TM5_RATIOMETRIC_CAL;
>> +	else
>> +		channel->cal_method = ADC_TM5_ABSOLUTE_CAL;
>> +
>> +	return 0;
>> +}
>> +
>> +static int adc_tm5_get_dt_data(struct adc_tm5_chip *adc_tm, struct device_node *node)
>> +{
>> +	struct adc_tm5_channel *channels;
>> +	struct device_node *child;
>> +	u32 value;
>> +	int ret;
>> +	struct device *dev = adc_tm->dev;
>> +
>> +	adc_tm->nchannels = of_get_available_child_count(node);
>> +	if (!adc_tm->nchannels)
>> +		return -EINVAL;
>> +
>> +	adc_tm->channels = devm_kcalloc(dev, adc_tm->nchannels,
>> +					sizeof(*adc_tm->channels), GFP_KERNEL);
>> +	if (!adc_tm->channels)
>> +		return -ENOMEM;
>> +
>> +	channels = adc_tm->channels;
>> +
>> +	adc_tm->data = of_device_get_match_data(dev);
>> +	if (!adc_tm->data)
>> +		adc_tm->data = &adc_tm5_data_pmic;
>> +
>> +	ret = of_property_read_u32(node, "qcom,decimation", &value);
>> +	if (!ret) {
>> +		ret = qcom_adc5_decimation_from_dt(value, adc_tm->data->decimation);
>> +		if (ret < 0) {
>> +			dev_err(dev, "invalid decimation %d\n", value);
>> +			return ret;
>> +		}
>> +		adc_tm->decimation = ret;
>> +	} else {
>> +		adc_tm->decimation = ADC5_DECIMATION_DEFAULT;
>> +	}
>> +
>> +	ret = of_property_read_u32(node, "qcom,avg-samples", &value);
>> +	if (!ret) {
>> +		ret = qcom_adc5_avg_samples_from_dt(value);
>> +		if (ret < 0) {
>> +			dev_err(dev, "invalid avg-samples %d\n", value);
>> +			return ret;
>> +		}
>> +		adc_tm->avg_samples = ret;
>> +	} else {
>> +		adc_tm->avg_samples = VADC_DEF_AVG_SAMPLES;
>> +	}
>> +
>> +	for_each_available_child_of_node(node, child) {
>> +		ret = adc_tm5_get_dt_channel_data(adc_tm, channels, child);
>> +		if (ret) {
>> +			of_node_put(child);
>> +			return ret;
>> +		}
>> +
>> +		channels++;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int adc_tm5_probe(struct platform_device *pdev)
>> +{
>> +	struct device_node *node = pdev->dev.of_node;
>> +	struct device *dev = &pdev->dev;
>> +	struct adc_tm5_chip *adc_tm;
>> +	struct regmap *regmap;
>> +	int ret, irq;
>> +	u32 reg;
>> +
>> +	regmap = dev_get_regmap(dev->parent, NULL);
>> +	if (!regmap)
>> +		return -ENODEV;
>> +
>> +	ret = of_property_read_u32(node, "reg", &reg);
>> +	if (ret)
>> +		return ret;
>> +
>> +	adc_tm = devm_kzalloc(&pdev->dev, sizeof(*adc_tm), GFP_KERNEL);
>> +	if (!adc_tm)
>> +		return -ENOMEM;
>> +
>> +	adc_tm->regmap = regmap;
>> +	adc_tm->dev = dev;
>> +	adc_tm->base = reg;
>> +
>> +	irq = platform_get_irq(pdev, 0);
>> +	if (irq < 0) {
>> +		dev_err(dev, "get_irq failed: %d\n", irq);
>> +		return irq;
>> +	}
>> +
>> +	ret = adc_tm5_get_dt_data(adc_tm, node);
>> +	if (ret) {
>> +		dev_err(dev, "get dt data failed: %d\n", ret);
>> +		return ret;
>> +	}
>> +
>> +	ret = adc_tm5_init(adc_tm);
>> +	if (ret) {
>> +		dev_err(dev, "adc-tm init failed\n");
>> +		return ret;
>> +	}
>> +
>> +	ret = adc_tm5_register_tzd(adc_tm);
>> +	if (ret) {
>> +		dev_err(dev, "tzd register failed\n");
>> +		return ret;
>> +	}
>> +
>> +	return devm_request_threaded_irq(dev, irq, NULL, adc_tm5_isr,
>> +					 IRQF_ONESHOT, "pm-adc-tm5", adc_tm);
>> +}
>> +
>> +static const struct of_device_id adc_tm5_match_table[] = {
>> +	{
>> +		.compatible = "qcom,spmi-adc-tm5",
>> +		.data = &adc_tm5_data_pmic,
>> +	},
>> +	{ }
>> +};
>> +MODULE_DEVICE_TABLE(of, adc_tm5_match_table);
>> +
>> +static struct platform_driver adc_tm5_driver = {
>> +	.driver = {
>> +		.name = "qcom-spmi-adc-tm5",
>> +		.of_match_table = adc_tm5_match_table,
>> +	},
>> +	.probe = adc_tm5_probe,
>> +};
>> +module_platform_driver(adc_tm5_driver);
>> +
>> +MODULE_DESCRIPTION("SPMI PMIC Thermal Monitor ADC driver");
>> +MODULE_LICENSE("GPL v2");
>> diff --git a/include/linux/iio/adc/qcom-vadc-common.h b/include/linux/iio/adc/qcom-vadc-common.h
>> index 58216124d89d..33f60f43e1aa 100644
>> --- a/include/linux/iio/adc/qcom-vadc-common.h
>> +++ b/include/linux/iio/adc/qcom-vadc-common.h
>> @@ -158,6 +158,9 @@ int qcom_adc5_hw_scale(enum vadc_scale_fn_type scaletype,
>>   		    const struct adc5_data *data,
>>   		    u16 adc_code, int *result_mdec);
>>   
>> +u16 qcom_adc_tm5_temp_volt_scale(unsigned int prescale_ratio,
>> +				 u32 full_scale_code_volt, int temp);
>> +
>>   int qcom_adc5_prescaling_from_dt(u32 num, u32 den);
>>   
>>   int qcom_adc5_hw_settle_time_from_dt(u32 value, const unsigned int *hw_settle);
>>
> 
> 


-- 
With best wishes
Dmitry