drivers/iio/adc/berlin2-adc.c - kernel/msm-4.9 - Gitiles

 /*
  * Marvell Berlin2 ADC driver
  *
  * Copyright (C) 2015 Marvell Technology Group Ltd.
  *
  * Antoine Tenart <antoine.tenart@free-electrons.com>
  *
  * This file is licensed under the terms of the GNU General Public
  * License version 2. This program is licensed "as is" without any
  * warranty of any kind, whether express or implied.
  */

 #include <linux/iio/iio.h>
 #include <linux/iio/driver.h>
 #include <linux/iio/machine.h>
 #include <linux/interrupt.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <linux/mfd/syscon.h>
 #include <linux/regmap.h>
 #include <linux/sched.h>
 #include <linux/wait.h>

 #define BERLIN2_SM_CTRL				0x14
 #define  BERLIN2_SM_CTRL_SM_SOC_INT		BIT(1)
 #define  BERLIN2_SM_CTRL_SOC_SM_INT		BIT(2)
 #define  BERLIN2_SM_CTRL_ADC_SEL(x)		((x) << 5)	/* 0-15 */
 #define  BERLIN2_SM_CTRL_ADC_SEL_MASK		(0xf << 5)
 #define  BERLIN2_SM_CTRL_ADC_POWER		BIT(9)
 #define  BERLIN2_SM_CTRL_ADC_CLKSEL_DIV2	(0x0 << 10)
 #define  BERLIN2_SM_CTRL_ADC_CLKSEL_DIV3	(0x1 << 10)
 #define  BERLIN2_SM_CTRL_ADC_CLKSEL_DIV4	(0x2 << 10)
 #define  BERLIN2_SM_CTRL_ADC_CLKSEL_DIV8	(0x3 << 10)
 #define  BERLIN2_SM_CTRL_ADC_CLKSEL_MASK	(0x3 << 10)
 #define  BERLIN2_SM_CTRL_ADC_START		BIT(12)
 #define  BERLIN2_SM_CTRL_ADC_RESET		BIT(13)
 #define  BERLIN2_SM_CTRL_ADC_BANDGAP_RDY	BIT(14)
 #define  BERLIN2_SM_CTRL_ADC_CONT_SINGLE	(0x0 << 15)
 #define  BERLIN2_SM_CTRL_ADC_CONT_CONTINUOUS	(0x1 << 15)
 #define  BERLIN2_SM_CTRL_ADC_BUFFER_EN		BIT(16)
 #define  BERLIN2_SM_CTRL_ADC_VREF_EXT		(0x0 << 17)
 #define  BERLIN2_SM_CTRL_ADC_VREF_INT		(0x1 << 17)
 #define  BERLIN2_SM_CTRL_ADC_ROTATE		BIT(19)
 #define  BERLIN2_SM_CTRL_TSEN_EN		BIT(20)
 #define  BERLIN2_SM_CTRL_TSEN_CLK_SEL_125	(0x0 << 21)	/* 1.25 MHz */
 #define  BERLIN2_SM_CTRL_TSEN_CLK_SEL_250	(0x1 << 21)	/* 2.5 MHz */
 #define  BERLIN2_SM_CTRL_TSEN_MODE_0_125	(0x0 << 22)	/* 0-125 C */
 #define  BERLIN2_SM_CTRL_TSEN_MODE_10_50	(0x1 << 22)	/* 10-50 C */
 #define  BERLIN2_SM_CTRL_TSEN_RESET		BIT(29)
 #define BERLIN2_SM_ADC_DATA			0x20
 #define  BERLIN2_SM_ADC_MASK			0x3ff
 #define BERLIN2_SM_ADC_STATUS			0x1c
 #define  BERLIN2_SM_ADC_STATUS_DATA_RDY(x)	BIT(x)		/* 0-15 */
 #define  BERLIN2_SM_ADC_STATUS_DATA_RDY_MASK	GENMASK(15, 0)
 #define  BERLIN2_SM_ADC_STATUS_INT_EN(x)	(BIT(x) << 16)	/* 0-15 */
 #define  BERLIN2_SM_ADC_STATUS_INT_EN_MASK	GENMASK(31, 16)
 #define BERLIN2_SM_TSEN_STATUS			0x24
 #define  BERLIN2_SM_TSEN_STATUS_DATA_RDY	BIT(0)
 #define  BERLIN2_SM_TSEN_STATUS_INT_EN		BIT(1)
 #define BERLIN2_SM_TSEN_DATA			0x28
 #define  BERLIN2_SM_TSEN_MASK			GENMASK(9, 0)
 #define BERLIN2_SM_TSEN_CTRL			0x74
 #define  BERLIN2_SM_TSEN_CTRL_START		BIT(8)
 #define  BERLIN2_SM_TSEN_CTRL_SETTLING_4	(0x0 << 21)	/* 4 us */
 #define  BERLIN2_SM_TSEN_CTRL_SETTLING_12	(0x1 << 21)	/* 12 us */
 #define  BERLIN2_SM_TSEN_CTRL_SETTLING_MASK	(0x1 << 21)
 #define  BERLIN2_SM_TSEN_CTRL_TRIM(x)		((x) << 22)
 #define  BERLIN2_SM_TSEN_CTRL_TRIM_MASK		(0xf << 22)

 struct berlin2_adc_priv {
 	struct regmap		*regmap;
 	struct mutex		lock;
 	wait_queue_head_t	wq;
 	bool			data_available;
 	int			data;
 };

 #define BERLIN2_ADC_CHANNEL(n, t)					\
 		{							\
 			.channel	= n,				\
 			.datasheet_name	= "channel"#n,			\
 			.type		= t,				\
 			.indexed	= 1,				\
 			.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),	\
 		}

 static const struct iio_chan_spec berlin2_adc_channels[] = {
 	BERLIN2_ADC_CHANNEL(0, IIO_VOLTAGE),	/* external input */
 	BERLIN2_ADC_CHANNEL(1, IIO_VOLTAGE),	/* external input */
 	BERLIN2_ADC_CHANNEL(2, IIO_VOLTAGE),	/* external input */
 	BERLIN2_ADC_CHANNEL(3, IIO_VOLTAGE),	/* external input */
 	BERLIN2_ADC_CHANNEL(4, IIO_VOLTAGE),	/* reserved */
 	BERLIN2_ADC_CHANNEL(5, IIO_VOLTAGE),	/* reserved */
 	{					/* temperature sensor */
 		.channel		= 6,
 		.datasheet_name		= "channel6",
 		.type			= IIO_TEMP,
 		.indexed		= 0,
 		.info_mask_separate	= BIT(IIO_CHAN_INFO_PROCESSED),
 	},
 	BERLIN2_ADC_CHANNEL(7, IIO_VOLTAGE),	/* reserved */
 	IIO_CHAN_SOFT_TIMESTAMP(8),		/* timestamp */
 };

 static int berlin2_adc_read(struct iio_dev *indio_dev, int channel)
 {
 	struct berlin2_adc_priv *priv = iio_priv(indio_dev);
 	int data, ret;

 	mutex_lock(&priv->lock);

 	/* Configure the ADC */
 	regmap_update_bits(priv->regmap, BERLIN2_SM_CTRL,
 			BERLIN2_SM_CTRL_ADC_RESET | BERLIN2_SM_CTRL_ADC_SEL_MASK
 			| BERLIN2_SM_CTRL_ADC_START,
 			BERLIN2_SM_CTRL_ADC_SEL(channel) | BERLIN2_SM_CTRL_ADC_START);

 	ret = wait_event_interruptible_timeout(priv->wq, priv->data_available,
 			msecs_to_jiffies(1000));

 	/* Disable the interrupts */
 	regmap_update_bits(priv->regmap, BERLIN2_SM_ADC_STATUS,
 			BERLIN2_SM_ADC_STATUS_INT_EN(channel), 0);

 	if (ret == 0)
 		ret = -ETIMEDOUT;
 	if (ret < 0) {
 		mutex_unlock(&priv->lock);
 		return ret;
 	}

 	regmap_update_bits(priv->regmap, BERLIN2_SM_CTRL,
 			BERLIN2_SM_CTRL_ADC_START, 0);

 	data = priv->data;
 	priv->data_available = false;

 	mutex_unlock(&priv->lock);

 	return data;
 }

 static int berlin2_adc_tsen_read(struct iio_dev *indio_dev)
 {
 	struct berlin2_adc_priv *priv = iio_priv(indio_dev);
 	int data, ret;

 	mutex_lock(&priv->lock);

 	/* Configure the ADC */
 	regmap_update_bits(priv->regmap, BERLIN2_SM_CTRL,
 			BERLIN2_SM_CTRL_TSEN_RESET | BERLIN2_SM_CTRL_ADC_ROTATE,
 			BERLIN2_SM_CTRL_ADC_ROTATE);

 	/* Configure the temperature sensor */
 	regmap_update_bits(priv->regmap, BERLIN2_SM_TSEN_CTRL,
 			BERLIN2_SM_TSEN_CTRL_TRIM_MASK | BERLIN2_SM_TSEN_CTRL_SETTLING_MASK
 			| BERLIN2_SM_TSEN_CTRL_START,
 			BERLIN2_SM_TSEN_CTRL_TRIM(3) | BERLIN2_SM_TSEN_CTRL_SETTLING_12
 			| BERLIN2_SM_TSEN_CTRL_START);

 	ret = wait_event_interruptible_timeout(priv->wq, priv->data_available,
 			msecs_to_jiffies(1000));

 	/* Disable interrupts */
 	regmap_update_bits(priv->regmap, BERLIN2_SM_TSEN_STATUS,
 			BERLIN2_SM_TSEN_STATUS_INT_EN, 0);

 	if (ret == 0)
 		ret = -ETIMEDOUT;
 	if (ret < 0) {
 		mutex_unlock(&priv->lock);
 		return ret;
 	}

 	regmap_update_bits(priv->regmap, BERLIN2_SM_TSEN_CTRL,
 			BERLIN2_SM_TSEN_CTRL_START, 0);

 	data = priv->data;
 	priv->data_available = false;

 	mutex_unlock(&priv->lock);

 	return data;
 }

 static int berlin2_adc_read_raw(struct iio_dev *indio_dev,
 		struct iio_chan_spec const *chan, int *val, int *val2,
 		long mask)
 {
 	struct berlin2_adc_priv *priv = iio_priv(indio_dev);
 	int temp;

 	switch (mask) {
 	case IIO_CHAN_INFO_RAW:
 		if (chan->type != IIO_VOLTAGE)
 			return -EINVAL;

 		/* Enable the interrupts */
 		regmap_write(priv->regmap, BERLIN2_SM_ADC_STATUS,
 				BERLIN2_SM_ADC_STATUS_INT_EN(chan->channel));

 		*val = berlin2_adc_read(indio_dev, chan->channel);
 		if (*val < 0)
 			return *val;

 		return IIO_VAL_INT;
 	case IIO_CHAN_INFO_PROCESSED:
 		if (chan->type != IIO_TEMP)
 			return -EINVAL;

 		/* Enable interrupts */
 		regmap_write(priv->regmap, BERLIN2_SM_TSEN_STATUS,
 				BERLIN2_SM_TSEN_STATUS_INT_EN);

 		temp = berlin2_adc_tsen_read(indio_dev);
 		if (temp < 0)
 			return temp;

 		if (temp > 2047)
 			temp -= 4096;

 		/* Convert to milli Celsius */
 		*val = ((temp * 100000) / 264 - 270000);
 		return IIO_VAL_INT;
 	default:
 		break;
 	}

 	return -EINVAL;
 }

 static irqreturn_t berlin2_adc_irq(int irq, void *private)
 {
 	struct berlin2_adc_priv *priv = iio_priv(private);
 	unsigned val;

 	regmap_read(priv->regmap, BERLIN2_SM_ADC_STATUS, &val);
 	if (val & BERLIN2_SM_ADC_STATUS_DATA_RDY_MASK) {
 		regmap_read(priv->regmap, BERLIN2_SM_ADC_DATA, &priv->data);
 		priv->data &= BERLIN2_SM_ADC_MASK;

 		val &= ~BERLIN2_SM_ADC_STATUS_DATA_RDY_MASK;
 		regmap_write(priv->regmap, BERLIN2_SM_ADC_STATUS, val);

 		priv->data_available = true;
 		wake_up_interruptible(&priv->wq);
 	}

 	return IRQ_HANDLED;
 }

 static irqreturn_t berlin2_adc_tsen_irq(int irq, void *private)
 {
 	struct berlin2_adc_priv *priv = iio_priv(private);
 	unsigned val;

 	regmap_read(priv->regmap, BERLIN2_SM_TSEN_STATUS, &val);
 	if (val & BERLIN2_SM_TSEN_STATUS_DATA_RDY) {
 		regmap_read(priv->regmap, BERLIN2_SM_TSEN_DATA, &priv->data);
 		priv->data &= BERLIN2_SM_TSEN_MASK;

 		val &= ~BERLIN2_SM_TSEN_STATUS_DATA_RDY;
 		regmap_write(priv->regmap, BERLIN2_SM_TSEN_STATUS, val);

 		priv->data_available = true;
 		wake_up_interruptible(&priv->wq);
 	}

 	return IRQ_HANDLED;
 }

 static const struct iio_info berlin2_adc_info = {
 	.driver_module	= THIS_MODULE,
 	.read_raw	= berlin2_adc_read_raw,
 };

 static int berlin2_adc_probe(struct platform_device *pdev)
 {
 	struct iio_dev *indio_dev;
 	struct berlin2_adc_priv *priv;
 	struct device_node *parent_np = of_get_parent(pdev->dev.of_node);
 	int irq, tsen_irq;
 	int ret;

 	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*priv));
 	if (!indio_dev)
 		return -ENOMEM;

 	priv = iio_priv(indio_dev);
 	platform_set_drvdata(pdev, indio_dev);

 	priv->regmap = syscon_node_to_regmap(parent_np);
 	of_node_put(parent_np);
 	if (IS_ERR(priv->regmap))
 		return PTR_ERR(priv->regmap);

 	irq = platform_get_irq_byname(pdev, "adc");
 	if (irq < 0)
 		return irq;

 	tsen_irq = platform_get_irq_byname(pdev, "tsen");
 	if (tsen_irq < 0)
 		return tsen_irq;

 	ret = devm_request_irq(&pdev->dev, irq, berlin2_adc_irq, 0,
 			pdev->dev.driver->name, indio_dev);
 	if (ret)
 		return ret;

 	ret = devm_request_irq(&pdev->dev, tsen_irq, berlin2_adc_tsen_irq,
 			0, pdev->dev.driver->name, indio_dev);
 	if (ret)
 		return ret;

 	init_waitqueue_head(&priv->wq);
 	mutex_init(&priv->lock);

 	indio_dev->dev.parent = &pdev->dev;
 	indio_dev->name = dev_name(&pdev->dev);
 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->info = &berlin2_adc_info;

 	indio_dev->channels = berlin2_adc_channels;
 	indio_dev->num_channels = ARRAY_SIZE(berlin2_adc_channels);

 	/* Power up the ADC */
 	regmap_update_bits(priv->regmap, BERLIN2_SM_CTRL,
 			BERLIN2_SM_CTRL_ADC_POWER, BERLIN2_SM_CTRL_ADC_POWER);

 	ret = iio_device_register(indio_dev);
 	if (ret) {
 		/* Power down the ADC */
 		regmap_update_bits(priv->regmap, BERLIN2_SM_CTRL,
 				BERLIN2_SM_CTRL_ADC_POWER, 0);
 		return ret;
 	}

 	return 0;
 }

 static int berlin2_adc_remove(struct platform_device *pdev)
 {
 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 	struct berlin2_adc_priv *priv = iio_priv(indio_dev);

 	iio_device_unregister(indio_dev);

 	/* Power down the ADC */
 	regmap_update_bits(priv->regmap, BERLIN2_SM_CTRL,
 			BERLIN2_SM_CTRL_ADC_POWER, 0);

 	return 0;
 }

 static const struct of_device_id berlin2_adc_match[] = {
 	{ .compatible = "marvell,berlin2-adc", },
 	{ },
 };
 MODULE_DEVICE_TABLE(of, berlin2_adc_match);

 static struct platform_driver berlin2_adc_driver = {
 	.driver	= {
 		.name		= "berlin2-adc",
 		.of_match_table	= berlin2_adc_match,
 	},
 	.probe	= berlin2_adc_probe,
 	.remove	= berlin2_adc_remove,
 };
 module_platform_driver(berlin2_adc_driver);

 MODULE_AUTHOR("Antoine Tenart <antoine.tenart@free-electrons.com>");
 MODULE_DESCRIPTION("Marvell Berlin2 ADC driver");
 MODULE_LICENSE("GPL v2");
	/*
	* Marvell Berlin2 ADC driver
	*
	* Copyright (C) 2015 Marvell Technology Group Ltd.
	*
	* Antoine Tenart <antoine.tenart@free-electrons.com>
	*
	* This file is licensed under the terms of the GNU General Public
	* License version 2. This program is licensed "as is" without any
	* warranty of any kind, whether express or implied.
	*/

	#include <linux/iio/iio.h>
	#include <linux/iio/driver.h>
	#include <linux/iio/machine.h>
	#include <linux/interrupt.h>
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/platform_device.h>
	#include <linux/slab.h>
	#include <linux/mfd/syscon.h>
	#include <linux/regmap.h>
	#include <linux/sched.h>
	#include <linux/wait.h>

	#define BERLIN2_SM_CTRL 0x14
	#define BERLIN2_SM_CTRL_SM_SOC_INT BIT(1)
	#define BERLIN2_SM_CTRL_SOC_SM_INT BIT(2)
	#define BERLIN2_SM_CTRL_ADC_SEL(x) ((x) << 5) /* 0-15 */
	#define BERLIN2_SM_CTRL_ADC_SEL_MASK (0xf << 5)
	#define BERLIN2_SM_CTRL_ADC_POWER BIT(9)
	#define BERLIN2_SM_CTRL_ADC_CLKSEL_DIV2 (0x0 << 10)
	#define BERLIN2_SM_CTRL_ADC_CLKSEL_DIV3 (0x1 << 10)
	#define BERLIN2_SM_CTRL_ADC_CLKSEL_DIV4 (0x2 << 10)
	#define BERLIN2_SM_CTRL_ADC_CLKSEL_DIV8 (0x3 << 10)
	#define BERLIN2_SM_CTRL_ADC_CLKSEL_MASK (0x3 << 10)
	#define BERLIN2_SM_CTRL_ADC_START BIT(12)
	#define BERLIN2_SM_CTRL_ADC_RESET BIT(13)
	#define BERLIN2_SM_CTRL_ADC_BANDGAP_RDY BIT(14)
	#define BERLIN2_SM_CTRL_ADC_CONT_SINGLE (0x0 << 15)
	#define BERLIN2_SM_CTRL_ADC_CONT_CONTINUOUS (0x1 << 15)
	#define BERLIN2_SM_CTRL_ADC_BUFFER_EN BIT(16)
	#define BERLIN2_SM_CTRL_ADC_VREF_EXT (0x0 << 17)
	#define BERLIN2_SM_CTRL_ADC_VREF_INT (0x1 << 17)
	#define BERLIN2_SM_CTRL_ADC_ROTATE BIT(19)
	#define BERLIN2_SM_CTRL_TSEN_EN BIT(20)
	#define BERLIN2_SM_CTRL_TSEN_CLK_SEL_125 (0x0 << 21) /* 1.25 MHz */
	#define BERLIN2_SM_CTRL_TSEN_CLK_SEL_250 (0x1 << 21) /* 2.5 MHz */
	#define BERLIN2_SM_CTRL_TSEN_MODE_0_125 (0x0 << 22) /* 0-125 C */
	#define BERLIN2_SM_CTRL_TSEN_MODE_10_50 (0x1 << 22) /* 10-50 C */
	#define BERLIN2_SM_CTRL_TSEN_RESET BIT(29)
	#define BERLIN2_SM_ADC_DATA 0x20
	#define BERLIN2_SM_ADC_MASK 0x3ff
	#define BERLIN2_SM_ADC_STATUS 0x1c
	#define BERLIN2_SM_ADC_STATUS_DATA_RDY(x) BIT(x) /* 0-15 */
	#define BERLIN2_SM_ADC_STATUS_DATA_RDY_MASK GENMASK(15, 0)
	#define BERLIN2_SM_ADC_STATUS_INT_EN(x) (BIT(x) << 16) /* 0-15 */
	#define BERLIN2_SM_ADC_STATUS_INT_EN_MASK GENMASK(31, 16)
	#define BERLIN2_SM_TSEN_STATUS 0x24
	#define BERLIN2_SM_TSEN_STATUS_DATA_RDY BIT(0)
	#define BERLIN2_SM_TSEN_STATUS_INT_EN BIT(1)
	#define BERLIN2_SM_TSEN_DATA 0x28
	#define BERLIN2_SM_TSEN_MASK GENMASK(9, 0)
	#define BERLIN2_SM_TSEN_CTRL 0x74
	#define BERLIN2_SM_TSEN_CTRL_START BIT(8)
	#define BERLIN2_SM_TSEN_CTRL_SETTLING_4 (0x0 << 21) /* 4 us */
	#define BERLIN2_SM_TSEN_CTRL_SETTLING_12 (0x1 << 21) /* 12 us */
	#define BERLIN2_SM_TSEN_CTRL_SETTLING_MASK (0x1 << 21)
	#define BERLIN2_SM_TSEN_CTRL_TRIM(x) ((x) << 22)
	#define BERLIN2_SM_TSEN_CTRL_TRIM_MASK (0xf << 22)

	struct berlin2_adc_priv {
	struct regmap *regmap;
	struct mutex lock;
	wait_queue_head_t wq;
	bool data_available;
	int data;
	};

	#define BERLIN2_ADC_CHANNEL(n, t) \
	{ \
	.channel = n, \
	.datasheet_name = "channel"#n, \
	.type = t, \
	.indexed = 1, \
	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
	}

	static const struct iio_chan_spec berlin2_adc_channels[] = {
	BERLIN2_ADC_CHANNEL(0, IIO_VOLTAGE), /* external input */
	BERLIN2_ADC_CHANNEL(1, IIO_VOLTAGE), /* external input */
	BERLIN2_ADC_CHANNEL(2, IIO_VOLTAGE), /* external input */
	BERLIN2_ADC_CHANNEL(3, IIO_VOLTAGE), /* external input */
	BERLIN2_ADC_CHANNEL(4, IIO_VOLTAGE), /* reserved */
	BERLIN2_ADC_CHANNEL(5, IIO_VOLTAGE), /* reserved */
	{ /* temperature sensor */
	.channel = 6,
	.datasheet_name = "channel6",
	.type = IIO_TEMP,
	.indexed = 0,
	.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
	},
	BERLIN2_ADC_CHANNEL(7, IIO_VOLTAGE), /* reserved */
	IIO_CHAN_SOFT_TIMESTAMP(8), /* timestamp */
	};

	static int berlin2_adc_read(struct iio_dev *indio_dev, int channel)
	{
	struct berlin2_adc_priv *priv = iio_priv(indio_dev);
	int data, ret;

	mutex_lock(&priv->lock);

	/* Configure the ADC */
	regmap_update_bits(priv->regmap, BERLIN2_SM_CTRL,
	BERLIN2_SM_CTRL_ADC_RESET \| BERLIN2_SM_CTRL_ADC_SEL_MASK
	\| BERLIN2_SM_CTRL_ADC_START,
	BERLIN2_SM_CTRL_ADC_SEL(channel) \| BERLIN2_SM_CTRL_ADC_START);

	ret = wait_event_interruptible_timeout(priv->wq, priv->data_available,
	msecs_to_jiffies(1000));

	/* Disable the interrupts */
	regmap_update_bits(priv->regmap, BERLIN2_SM_ADC_STATUS,
	BERLIN2_SM_ADC_STATUS_INT_EN(channel), 0);

	if (ret == 0)
	ret = -ETIMEDOUT;
	if (ret < 0) {
	mutex_unlock(&priv->lock);
	return ret;
	}

	regmap_update_bits(priv->regmap, BERLIN2_SM_CTRL,
	BERLIN2_SM_CTRL_ADC_START, 0);

	data = priv->data;
	priv->data_available = false;

	mutex_unlock(&priv->lock);

	return data;
	}

	static int berlin2_adc_tsen_read(struct iio_dev *indio_dev)
	{
	struct berlin2_adc_priv *priv = iio_priv(indio_dev);
	int data, ret;

	mutex_lock(&priv->lock);

	/* Configure the ADC */
	regmap_update_bits(priv->regmap, BERLIN2_SM_CTRL,
	BERLIN2_SM_CTRL_TSEN_RESET \| BERLIN2_SM_CTRL_ADC_ROTATE,
	BERLIN2_SM_CTRL_ADC_ROTATE);

	/* Configure the temperature sensor */
	regmap_update_bits(priv->regmap, BERLIN2_SM_TSEN_CTRL,
	BERLIN2_SM_TSEN_CTRL_TRIM_MASK \| BERLIN2_SM_TSEN_CTRL_SETTLING_MASK
	\| BERLIN2_SM_TSEN_CTRL_START,
	BERLIN2_SM_TSEN_CTRL_TRIM(3) \| BERLIN2_SM_TSEN_CTRL_SETTLING_12
	\| BERLIN2_SM_TSEN_CTRL_START);

	ret = wait_event_interruptible_timeout(priv->wq, priv->data_available,
	msecs_to_jiffies(1000));

	/* Disable interrupts */
	regmap_update_bits(priv->regmap, BERLIN2_SM_TSEN_STATUS,
	BERLIN2_SM_TSEN_STATUS_INT_EN, 0);

	if (ret == 0)
	ret = -ETIMEDOUT;
	if (ret < 0) {
	mutex_unlock(&priv->lock);
	return ret;
	}

	regmap_update_bits(priv->regmap, BERLIN2_SM_TSEN_CTRL,
	BERLIN2_SM_TSEN_CTRL_START, 0);

	data = priv->data;
	priv->data_available = false;

	mutex_unlock(&priv->lock);

	return data;
	}

	static int berlin2_adc_read_raw(struct iio_dev *indio_dev,
	struct iio_chan_spec const chan, int val, int *val2,
	long mask)
	{
	struct berlin2_adc_priv *priv = iio_priv(indio_dev);
	int temp;

	switch (mask) {
	case IIO_CHAN_INFO_RAW:
	if (chan->type != IIO_VOLTAGE)
	return -EINVAL;

	/* Enable the interrupts */
	regmap_write(priv->regmap, BERLIN2_SM_ADC_STATUS,
	BERLIN2_SM_ADC_STATUS_INT_EN(chan->channel));

	*val = berlin2_adc_read(indio_dev, chan->channel);
	if (*val < 0)
	return *val;

	return IIO_VAL_INT;
	case IIO_CHAN_INFO_PROCESSED:
	if (chan->type != IIO_TEMP)
	return -EINVAL;

	/* Enable interrupts */
	regmap_write(priv->regmap, BERLIN2_SM_TSEN_STATUS,
	BERLIN2_SM_TSEN_STATUS_INT_EN);

	temp = berlin2_adc_tsen_read(indio_dev);
	if (temp < 0)
	return temp;

	if (temp > 2047)
	temp -= 4096;

	/* Convert to milli Celsius */
	val = ((temp 100000) / 264 - 270000);
	return IIO_VAL_INT;
	default:
	break;
	}

	return -EINVAL;
	}

	static irqreturn_t berlin2_adc_irq(int irq, void *private)
	{
	struct berlin2_adc_priv *priv = iio_priv(private);
	unsigned val;

	regmap_read(priv->regmap, BERLIN2_SM_ADC_STATUS, &val);
	if (val & BERLIN2_SM_ADC_STATUS_DATA_RDY_MASK) {
	regmap_read(priv->regmap, BERLIN2_SM_ADC_DATA, &priv->data);
	priv->data &= BERLIN2_SM_ADC_MASK;

	val &= ~BERLIN2_SM_ADC_STATUS_DATA_RDY_MASK;
	regmap_write(priv->regmap, BERLIN2_SM_ADC_STATUS, val);

	priv->data_available = true;
	wake_up_interruptible(&priv->wq);
	}

	return IRQ_HANDLED;
	}

	static irqreturn_t berlin2_adc_tsen_irq(int irq, void *private)
	{
	struct berlin2_adc_priv *priv = iio_priv(private);
	unsigned val;

	regmap_read(priv->regmap, BERLIN2_SM_TSEN_STATUS, &val);
	if (val & BERLIN2_SM_TSEN_STATUS_DATA_RDY) {
	regmap_read(priv->regmap, BERLIN2_SM_TSEN_DATA, &priv->data);
	priv->data &= BERLIN2_SM_TSEN_MASK;

	val &= ~BERLIN2_SM_TSEN_STATUS_DATA_RDY;
	regmap_write(priv->regmap, BERLIN2_SM_TSEN_STATUS, val);

	priv->data_available = true;
	wake_up_interruptible(&priv->wq);
	}

	return IRQ_HANDLED;
	}

	static const struct iio_info berlin2_adc_info = {
	.driver_module = THIS_MODULE,
	.read_raw = berlin2_adc_read_raw,
	};

	static int berlin2_adc_probe(struct platform_device *pdev)
	{
	struct iio_dev *indio_dev;
	struct berlin2_adc_priv *priv;
	struct device_node *parent_np = of_get_parent(pdev->dev.of_node);
	int irq, tsen_irq;
	int ret;

	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*priv));
	if (!indio_dev)
	return -ENOMEM;

	priv = iio_priv(indio_dev);
	platform_set_drvdata(pdev, indio_dev);

	priv->regmap = syscon_node_to_regmap(parent_np);
	of_node_put(parent_np);
	if (IS_ERR(priv->regmap))
	return PTR_ERR(priv->regmap);

	irq = platform_get_irq_byname(pdev, "adc");
	if (irq < 0)
	return irq;

	tsen_irq = platform_get_irq_byname(pdev, "tsen");
	if (tsen_irq < 0)
	return tsen_irq;

	ret = devm_request_irq(&pdev->dev, irq, berlin2_adc_irq, 0,
	pdev->dev.driver->name, indio_dev);
	if (ret)
	return ret;

	ret = devm_request_irq(&pdev->dev, tsen_irq, berlin2_adc_tsen_irq,
	0, pdev->dev.driver->name, indio_dev);
	if (ret)
	return ret;

	init_waitqueue_head(&priv->wq);
	mutex_init(&priv->lock);

	indio_dev->dev.parent = &pdev->dev;
	indio_dev->name = dev_name(&pdev->dev);
	indio_dev->modes = INDIO_DIRECT_MODE;
	indio_dev->info = &berlin2_adc_info;

	indio_dev->channels = berlin2_adc_channels;
	indio_dev->num_channels = ARRAY_SIZE(berlin2_adc_channels);

	/* Power up the ADC */
	regmap_update_bits(priv->regmap, BERLIN2_SM_CTRL,
	BERLIN2_SM_CTRL_ADC_POWER, BERLIN2_SM_CTRL_ADC_POWER);

	ret = iio_device_register(indio_dev);
	if (ret) {
	/* Power down the ADC */
	regmap_update_bits(priv->regmap, BERLIN2_SM_CTRL,
	BERLIN2_SM_CTRL_ADC_POWER, 0);
	return ret;
	}

	return 0;
	}

	static int berlin2_adc_remove(struct platform_device *pdev)
	{
	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
	struct berlin2_adc_priv *priv = iio_priv(indio_dev);

	iio_device_unregister(indio_dev);

	/* Power down the ADC */
	regmap_update_bits(priv->regmap, BERLIN2_SM_CTRL,
	BERLIN2_SM_CTRL_ADC_POWER, 0);

	return 0;
	}

	static const struct of_device_id berlin2_adc_match[] = {
	{ .compatible = "marvell,berlin2-adc", },
	{ },
	};
	MODULE_DEVICE_TABLE(of, berlin2_adc_match);

	static struct platform_driver berlin2_adc_driver = {
	.driver = {
	.name = "berlin2-adc",
	.of_match_table = berlin2_adc_match,
	},
	.probe = berlin2_adc_probe,
	.remove = berlin2_adc_remove,
	};
	module_platform_driver(berlin2_adc_driver);

	MODULE_AUTHOR("Antoine Tenart <antoine.tenart@free-electrons.com>");
	MODULE_DESCRIPTION("Marvell Berlin2 ADC driver");
	MODULE_LICENSE("GPL v2");