drivers/iio/adc/berlin2-adc.c - kernel/common - Git at Google


            
            /*

            
             * Marvell Berlin2 ADC driver

            
             *

            
             * Copyright (C) 2015 Marvell Technology Group Ltd.

            
             *

            
             * Antoine Tenart <[email protected]>

            
             *

            
             * 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		GENMASK(8, 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	GENMASK(11, 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			GENMASK(9, 0)

            
            #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	BIT(21)

            
            #define  BERLIN2_SM_TSEN_CTRL_TRIM(x)		((x) << 22)

            
            #define  BERLIN2_SM_TSEN_CTRL_TRIM_MASK		GENMASK(25, 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);


            	/* Enable the interrupts */

            
            	regmap_write(priv->regmap, BERLIN2_SM_ADC_STATUS,

            
            		     BERLIN2_SM_ADC_STATUS_INT_EN(channel));


            	/* 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);


            	/* Enable interrupts */

            
            	regmap_write(priv->regmap, BERLIN2_SM_TSEN_STATUS,

            
            		     BERLIN2_SM_TSEN_STATUS_INT_EN);


            	/* 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)

            
            {

            
            	int temp;


            	switch (mask) {

            
            	case IIO_CHAN_INFO_RAW:

            
            		if (chan->type != IIO_VOLTAGE)

            
            			return -EINVAL;


            		*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;


            		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 <[email protected]>");

            
            MODULE_DESCRIPTION("Marvell Berlin2 ADC driver");

            
            MODULE_LICENSE("GPL v2");
	/*
	* Marvell Berlin2 ADC driver
	*
	* Copyright (C) 2015 Marvell Technology Group Ltd.
	*
	* Antoine Tenart <[email protected]>
	*
	* 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 GENMASK(8, 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 GENMASK(11, 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 GENMASK(9, 0)
	#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 BIT(21)
	#define BERLIN2_SM_TSEN_CTRL_TRIM(x) ((x) << 22)
	#define BERLIN2_SM_TSEN_CTRL_TRIM_MASK GENMASK(25, 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);

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

	/* 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);

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

	/* 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)
	{
	int temp;

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

	*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;

	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 <[email protected]>");
	MODULE_DESCRIPTION("Marvell Berlin2 ADC driver");
	MODULE_LICENSE("GPL v2");