Commit 7abd9fb6 authored by Saravanan Sekar's avatar Saravanan Sekar Committed by Lee Jones
Browse files

iio: adc: mp2629: Add support for mp2629 ADC driver 



Add support for 8-bit resolution ADC readings for input power
supply and battery charging measurement. Provides voltage, current
readings to mp2629 power supply driver.

Signed-off-by: default avatarSaravanan Sekar <sravanhome@gmail.com>
Reviewed-by: default avatarAndy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: default avatarLee Jones <lee.jones@linaro.org>
parent 06081646

drivers/iio/adc/Kconfig

+10 −0
Original line number Diff line number Diff line
@@ -692,6 +692,16 @@ config MESON_SARADC 
	  To compile this driver as a module, choose M here: the

	  module will be called meson_saradc.



config MP2629_ADC

	tristate "Monolithic MP2629 ADC driver"

	depends on MFD_MP2629

	help

	  Say yes to have support for battery charger IC MP2629 ADC device

	  accessed over I2C.



	  This driver provides ADC conversion of system, input power supply

	  and battery voltage & current information.



config NAU7802

	tristate "Nuvoton NAU7802 ADC driver"

	depends on I2C

drivers/iio/adc/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -65,6 +65,7 @@ obj-$(CONFIG_MCP3911) += mcp3911.o 
obj-$(CONFIG_MEDIATEK_MT6577_AUXADC) += mt6577_auxadc.o

obj-$(CONFIG_MEN_Z188_ADC) += men_z188_adc.o

obj-$(CONFIG_MESON_SARADC) += meson_saradc.o

obj-$(CONFIG_MP2629_ADC) += mp2629_adc.o

obj-$(CONFIG_MXS_LRADC_ADC) += mxs-lradc-adc.o

obj-$(CONFIG_NAU7802) += nau7802.o

obj-$(CONFIG_NPCM_ADC) += npcm_adc.o

drivers/iio/adc/mp2629_adc.c

0 → 100644
+208 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0-or-later

/*

 * MP2629 Driver for ADC

 *

 * Copyright 2020 Monolithic Power Systems, Inc

 *

 * Author: Saravanan Sekar <sravanhome@gmail.com>

 */



#include <linux/iio/driver.h>

#include <linux/iio/iio.h>

#include <linux/iio/machine.h>

#include <linux/mfd/mp2629.h>

#include <linux/module.h>

#include <linux/mutex.h>

#include <linux/platform_device.h>

#include <linux/regmap.h>



#define	MP2629_REG_ADC_CTRL		0x03

#define	MP2629_REG_BATT_VOLT		0x0e

#define	MP2629_REG_SYSTEM_VOLT		0x0f

#define	MP2629_REG_INPUT_VOLT		0x11

#define	MP2629_REG_BATT_CURRENT		0x12

#define	MP2629_REG_INPUT_CURRENT	0x13



#define	MP2629_ADC_START		BIT(7)

#define	MP2629_ADC_CONTINUOUS		BIT(6)



#define MP2629_MAP(_mp, _mpc) IIO_MAP(#_mp, "mp2629_charger", "mp2629-"_mpc)



#define MP2629_ADC_CHAN(_ch, _type) {				\

	.type = _type,						\

	.indexed = 1,						\

	.datasheet_name = #_ch,					\

	.channel = MP2629_ ## _ch,				\

	.address = MP2629_REG_ ## _ch,				\

	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\

	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\

}



struct mp2629_adc {

	struct regmap *regmap;

	struct device *dev;

};



static struct iio_chan_spec mp2629_channels[] = {

	MP2629_ADC_CHAN(BATT_VOLT, IIO_VOLTAGE),

	MP2629_ADC_CHAN(SYSTEM_VOLT, IIO_VOLTAGE),

	MP2629_ADC_CHAN(INPUT_VOLT, IIO_VOLTAGE),

	MP2629_ADC_CHAN(BATT_CURRENT, IIO_CURRENT),

	MP2629_ADC_CHAN(INPUT_CURRENT, IIO_CURRENT)

};



static struct iio_map mp2629_adc_maps[] = {

	MP2629_MAP(BATT_VOLT, "batt-volt"),

	MP2629_MAP(SYSTEM_VOLT, "system-volt"),

	MP2629_MAP(INPUT_VOLT, "input-volt"),

	MP2629_MAP(BATT_CURRENT, "batt-current"),

	MP2629_MAP(INPUT_CURRENT, "input-current")

};



static int mp2629_read_raw(struct iio_dev *indio_dev,

			struct iio_chan_spec const *chan,

			int *val, int *val2, long mask)

{

	struct mp2629_adc *info = iio_priv(indio_dev);

	unsigned int rval;

	int ret;



	switch (mask) {

	case IIO_CHAN_INFO_RAW:

		ret = regmap_read(info->regmap, chan->address, &rval);

		if (ret)

			return ret;



		if (chan->address == MP2629_INPUT_VOLT)

			rval &= GENMASK(6, 0);

		*val = rval;

		return IIO_VAL_INT;



	case IIO_CHAN_INFO_SCALE:

		switch (chan->channel) {

		case MP2629_BATT_VOLT:

		case MP2629_SYSTEM_VOLT:

			*val = 20;

			return IIO_VAL_INT;



		case MP2629_INPUT_VOLT:

			*val = 60;

			return IIO_VAL_INT;



		case MP2629_BATT_CURRENT:

			*val = 175;

			*val2 = 10;

			return IIO_VAL_FRACTIONAL;



		case MP2629_INPUT_CURRENT:

			*val = 133;

			*val2 = 10;

			return IIO_VAL_FRACTIONAL;



		default:

			return -EINVAL;

		}



	default:

		return -EINVAL;

	}

}



static const struct iio_info mp2629_adc_info = {

	.read_raw = &mp2629_read_raw,

};



static int mp2629_adc_probe(struct platform_device *pdev)

{

	struct device *dev = &pdev->dev;

	struct mp2629_data *ddata = dev_get_drvdata(dev->parent);

	struct mp2629_adc *info;

	struct iio_dev *indio_dev;

	int ret;



	indio_dev = devm_iio_device_alloc(dev, sizeof(*info));

	if (!indio_dev)

		return -ENOMEM;



	info = iio_priv(indio_dev);

	info->regmap = ddata->regmap;

	info->dev = dev;

	platform_set_drvdata(pdev, indio_dev);



	ret = regmap_update_bits(info->regmap, MP2629_REG_ADC_CTRL,

				MP2629_ADC_START | MP2629_ADC_CONTINUOUS,

				MP2629_ADC_START | MP2629_ADC_CONTINUOUS);

	if (ret) {

		dev_err(dev, "adc enable fail: %d\n", ret);

		return ret;

	}



	ret = iio_map_array_register(indio_dev, mp2629_adc_maps);

	if (ret) {

		dev_err(dev, "IIO maps register fail: %d\n", ret);

		goto fail_disable;

	}



	indio_dev->name = "mp2629-adc";

	indio_dev->dev.parent = dev;

	indio_dev->channels = mp2629_channels;

	indio_dev->num_channels = ARRAY_SIZE(mp2629_channels);

	indio_dev->modes = INDIO_DIRECT_MODE;

	indio_dev->info = &mp2629_adc_info;



	ret = iio_device_register(indio_dev);

	if (ret) {

		dev_err(dev, "IIO device register fail: %d\n", ret);

		goto fail_map_unregister;

	}



	return 0;



fail_map_unregister:

	iio_map_array_unregister(indio_dev);



fail_disable:

	regmap_update_bits(info->regmap, MP2629_REG_ADC_CTRL,

					 MP2629_ADC_CONTINUOUS, 0);

	regmap_update_bits(info->regmap, MP2629_REG_ADC_CTRL,

					 MP2629_ADC_START, 0);



	return ret;

}



static int mp2629_adc_remove(struct platform_device *pdev)

{

	struct iio_dev *indio_dev = platform_get_drvdata(pdev);

	struct mp2629_adc *info = iio_priv(indio_dev);



	iio_device_unregister(indio_dev);



	iio_map_array_unregister(indio_dev);



	regmap_update_bits(info->regmap, MP2629_REG_ADC_CTRL,

					 MP2629_ADC_CONTINUOUS, 0);

	regmap_update_bits(info->regmap, MP2629_REG_ADC_CTRL,

					 MP2629_ADC_START, 0);



	return 0;

}



static const struct of_device_id mp2629_adc_of_match[] = {

	{ .compatible = "mps,mp2629_adc"},

	{}

};

MODULE_DEVICE_TABLE(of, mp2629_adc_of_match);



static struct platform_driver mp2629_adc_driver = {

	.driver = {

		.name = "mp2629_adc",

		.of_match_table = mp2629_adc_of_match,

	},

	.probe		= mp2629_adc_probe,

	.remove		= mp2629_adc_remove,

};

module_platform_driver(mp2629_adc_driver);



MODULE_AUTHOR("Saravanan Sekar <sravanhome@gmail.com>");

MODULE_DESCRIPTION("MP2629 ADC driver");

MODULE_LICENSE("GPL");

include/linux/mfd/mp2629.h

+9 −0
Original line number Diff line number Diff line
@@ -14,4 +14,13 @@ struct mp2629_data { 
	struct regmap *regmap;

};



enum mp2629_adc_chan {

	MP2629_BATT_VOLT,

	MP2629_SYSTEM_VOLT,

	MP2629_INPUT_VOLT,

	MP2629_BATT_CURRENT,

	MP2629_INPUT_CURRENT,

	MP2629_ADC_CHAN_END

};



#endif

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