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Commit 913b8646 authored by Angelo Compagnucci's avatar Angelo Compagnucci Committed by Jonathan Cameron
Browse files

iio: adc: Add TI ADC128S052 



This patch adds support for ADC128S052 from TI.

Signed-off-by: default avatarAngelo Compagnucci <angelo.compagnucci@gmail.com>
Signed-off-by: default avatarJonathan Cameron <jic23@kernel.org>
parent 7144045d

drivers/iio/adc/Kconfig

+10 −0
Original line number Diff line number Diff line
@@ -216,6 +216,16 @@ config TI_ADC081C 
	  This driver can also be built as a module. If so, the module will be

	  called ti-adc081c.



config TI_ADC128S052

	tristate "Texas Instruments ADC128S052"

	depends on SPI

	help

	  If you say yes here you get support for Texas Instruments ADC128S052

	  chip.



	  This driver can also be built as a module. If so, the module will be

	  called ti-adc128s052.



config TI_AM335X_ADC

	tristate "TI's AM335X ADC driver"

	depends on MFD_TI_AM335X_TSCADC

drivers/iio/adc/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -23,6 +23,7 @@ obj-$(CONFIG_MCP3422) += mcp3422.o 
obj-$(CONFIG_MEN_Z188_ADC) += men_z188_adc.o

obj-$(CONFIG_NAU7802) += nau7802.o

obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o

obj-$(CONFIG_TI_ADC128S052) += ti-adc128s052.o

obj-$(CONFIG_TI_AM335X_ADC) += ti_am335x_adc.o

obj-$(CONFIG_TWL4030_MADC) += twl4030-madc.o

obj-$(CONFIG_TWL6030_GPADC) += twl6030-gpadc.o

drivers/iio/adc/ti-adc128s052.c

0 → 100644
+179 −0
Original line number Diff line number Diff line 
/*

 * Copyright (C) 2014 Angelo Compagnucci <angelo.compagnucci@gmail.com>

 *

 * Driver for Texas Instruments' ADC128S052 ADC chip.

 * Datasheet can be found here:

 * http://www.ti.com/lit/ds/symlink/adc128s052.pdf

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 */



#include <linux/err.h>

#include <linux/spi/spi.h>

#include <linux/module.h>

#include <linux/iio/iio.h>

#include <linux/regulator/consumer.h>



struct adc128 {

	struct spi_device *spi;



	struct regulator *reg;

	struct mutex lock;



	u8 buffer[2] ____cacheline_aligned;

};



static int adc128_adc_conversion(struct adc128 *adc, u8 channel)

{

	int ret;



	mutex_lock(&adc->lock);



	adc->buffer[0] = channel << 3;

	adc->buffer[1] = 0;



	ret = spi_write(adc->spi, &adc->buffer, 2);

	if (ret < 0) {

		mutex_unlock(&adc->lock);

		return ret;

	}



	ret = spi_read(adc->spi, &adc->buffer, 2);



	mutex_unlock(&adc->lock);



	if (ret < 0)

		return ret;



	return ((adc->buffer[0] << 8 | adc->buffer[1]) & 0xFFF);

}



static int adc128_read_raw(struct iio_dev *indio_dev,

			   struct iio_chan_spec const *channel, int *val,

			   int *val2, long mask)

{

	struct adc128 *adc = iio_priv(indio_dev);

	int ret;



	switch (mask) {

	case IIO_CHAN_INFO_RAW:



		ret = adc128_adc_conversion(adc, channel->channel);

		if (ret < 0)

			return ret;



		*val = ret;

		return IIO_VAL_INT;



	case IIO_CHAN_INFO_SCALE:



		ret = regulator_get_voltage(adc->reg);

		if (ret < 0)

			return ret;



		*val = ret / 1000;

		*val2 = 12;

		return IIO_VAL_FRACTIONAL_LOG2;



	default:

		return -EINVAL;

	}



}



#define ADC128_VOLTAGE_CHANNEL(num)	\

	{ \

		.type = IIO_VOLTAGE, \

		.indexed = 1, \

		.channel = (num), \

		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \

		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) \

	}



static const struct iio_chan_spec adc128_channels[] = {

	ADC128_VOLTAGE_CHANNEL(0),

	ADC128_VOLTAGE_CHANNEL(1),

	ADC128_VOLTAGE_CHANNEL(2),

	ADC128_VOLTAGE_CHANNEL(3),

	ADC128_VOLTAGE_CHANNEL(4),

	ADC128_VOLTAGE_CHANNEL(5),

	ADC128_VOLTAGE_CHANNEL(6),

	ADC128_VOLTAGE_CHANNEL(7),

};



static const struct iio_info adc128_info = {

	.read_raw = adc128_read_raw,

	.driver_module = THIS_MODULE,

};



static int adc128_probe(struct spi_device *spi)

{

	struct iio_dev *indio_dev;

	struct adc128 *adc;

	int ret;



	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*adc));

	if (!indio_dev)

		return -ENOMEM;



	adc = iio_priv(indio_dev);

	adc->spi = spi;



	spi_set_drvdata(spi, indio_dev);



	indio_dev->dev.parent = &spi->dev;

	indio_dev->name = spi_get_device_id(spi)->name;

	indio_dev->modes = INDIO_DIRECT_MODE;

	indio_dev->info = &adc128_info;



	indio_dev->channels = adc128_channels;

	indio_dev->num_channels = ARRAY_SIZE(adc128_channels);



	adc->reg = devm_regulator_get(&spi->dev, "vref");

	if (IS_ERR(adc->reg))

		return PTR_ERR(adc->reg);



	ret = regulator_enable(adc->reg);

	if (ret < 0)

		return ret;



	mutex_init(&adc->lock);



	ret = iio_device_register(indio_dev);



	return ret;

}



static int adc128_remove(struct spi_device *spi)

{

	struct iio_dev *indio_dev = spi_get_drvdata(spi);

	struct adc128 *adc = iio_priv(indio_dev);



	iio_device_unregister(indio_dev);

	regulator_disable(adc->reg);



	return 0;

}



static const struct spi_device_id adc128_id[] = {

	{ "adc128s052", 0},

	{ }

};

MODULE_DEVICE_TABLE(spi, adc128_id);



static struct spi_driver adc128_driver = {

	.driver = {

		.name = "adc128s052",

		.owner = THIS_MODULE,

	},

	.probe = adc128_probe,

	.remove = adc128_remove,

	.id_table = adc128_id,

};

module_spi_driver(adc128_driver);



MODULE_AUTHOR("Angelo Compagnucci <angelo.compagnucci@gmail.com>");

MODULE_DESCRIPTION("Texas Instruments ADC128S052");

MODULE_LICENSE("GPL v2");