[linux-2.6-block.git] / drivers / iio / temperature / mlx90614.c

/*
 * mlx90614.c - Support for Melexis MLX90614 contactless IR temperature sensor
 *
 * Copyright (c) 2014 Peter Meerwald <pmeerw@pmeerw.net>
 * Copyright (c) 2015 Essensium NV
 * Copyright (c) 2015 Melexis
 *
 * This file is subject to the terms and conditions of version 2 of
 * the GNU General Public License.  See the file COPYING in the main
 * directory of this archive for more details.
 *
 * Driver for the Melexis MLX90614 I2C 16-bit IR thermopile sensor
 *
 * (7-bit I2C slave address 0x5a, 100KHz bus speed only!)
 *
 * To wake up from sleep mode, the SDA line must be held low while SCL is high
 * for at least 33ms.  This is achieved with an extra GPIO that can be connected
 * directly to the SDA line.  In normal operation, the GPIO is set as input and
 * will not interfere in I2C communication.  While the GPIO is driven low, the
 * i2c adapter is locked since it cannot be used by other clients.  The SCL line
 * always has a pull-up so we do not need an extra GPIO to drive it high.  If
 * the "wakeup" GPIO is not given, power management will be disabled.
 *
 */

#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/jiffies.h>
#include <linux/gpio/consumer.h>
#include <linux/pm_runtime.h>

#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>

#define MLX90614_OP_RAM		0x00
#define MLX90614_OP_EEPROM	0x20
#define MLX90614_OP_SLEEP	0xff

/* RAM offsets with 16-bit data, MSB first */
#define MLX90614_RAW1	(MLX90614_OP_RAM | 0x04) /* raw data IR channel 1 */
#define MLX90614_RAW2	(MLX90614_OP_RAM | 0x05) /* raw data IR channel 2 */
#define MLX90614_TA	(MLX90614_OP_RAM | 0x06) /* ambient temperature */
#define MLX90614_TOBJ1	(MLX90614_OP_RAM | 0x07) /* object 1 temperature */
#define MLX90614_TOBJ2	(MLX90614_OP_RAM | 0x08) /* object 2 temperature */

/* EEPROM offsets with 16-bit data, MSB first */
#define MLX90614_EMISSIVITY	(MLX90614_OP_EEPROM | 0x04) /* emissivity correction coefficient */
#define MLX90614_CONFIG		(MLX90614_OP_EEPROM | 0x05) /* configuration register */

/* Control bits in configuration register */
#define MLX90614_CONFIG_IIR_SHIFT 0 /* IIR coefficient */
#define MLX90614_CONFIG_IIR_MASK (0x7 << MLX90614_CONFIG_IIR_SHIFT)
#define MLX90614_CONFIG_DUAL_SHIFT 6 /* single (0) or dual (1) IR sensor */
#define MLX90614_CONFIG_DUAL_MASK (1 << MLX90614_CONFIG_DUAL_SHIFT)
#define MLX90614_CONFIG_FIR_SHIFT 8 /* FIR coefficient */
#define MLX90614_CONFIG_FIR_MASK (0x7 << MLX90614_CONFIG_FIR_SHIFT)
#define MLX90614_CONFIG_GAIN_SHIFT 11 /* gain */
#define MLX90614_CONFIG_GAIN_MASK (0x7 << MLX90614_CONFIG_GAIN_SHIFT)

/* Timings (in ms) */
#define MLX90614_TIMING_EEPROM 20 /* time for EEPROM write/erase to complete */
#define MLX90614_TIMING_WAKEUP 34 /* time to hold SDA low for wake-up */
#define MLX90614_TIMING_STARTUP 250 /* time before first data after wake-up */

#define MLX90614_AUTOSLEEP_DELAY 5000 /* default autosleep delay */

/* Magic constants */
#define MLX90614_CONST_OFFSET_DEC -13657 /* decimal part of the Kelvin offset */
#define MLX90614_CONST_OFFSET_REM 500000 /* remainder of offset (273.15*50) */
#define MLX90614_CONST_SCALE 20 /* Scale in milliKelvin (0.02 * 1000) */
#define MLX90614_CONST_RAW_EMISSIVITY_MAX 65535 /* max value for emissivity */
#define MLX90614_CONST_EMISSIVITY_RESOLUTION 15259 /* 1/65535 ~ 0.000015259 */

struct mlx90614_data {
	struct i2c_client *client;
	struct mutex lock; /* for EEPROM access only */
	struct gpio_desc *wakeup_gpio; /* NULL to disable sleep/wake-up */
	unsigned long ready_timestamp; /* in jiffies */
};

/* Bandwidth values for IIR filtering */
static const int mlx90614_iir_values[] = {77, 31, 20, 15, 723, 153, 110, 86};
static IIO_CONST_ATTR(in_temp_object_filter_low_pass_3db_frequency_available,
		      "0.15 0.20 0.31 0.77 0.86 1.10 1.53 7.23");

static struct attribute *mlx90614_attributes[] = {
	&iio_const_attr_in_temp_object_filter_low_pass_3db_frequency_available.dev_attr.attr,
	NULL,
};

static const struct attribute_group mlx90614_attr_group = {
	.attrs = mlx90614_attributes,
};

/*
 * Erase an address and write word.
 * The mutex must be locked before calling.
 */
static s32 mlx90614_write_word(const struct i2c_client *client, u8 command,
			       u16 value)
{
	/*
	 * Note: The mlx90614 requires a PEC on writing but does not send us a
	 * valid PEC on reading.  Hence, we cannot set I2C_CLIENT_PEC in
	 * i2c_client.flags.  As a workaround, we use i2c_smbus_xfer here.
	 */
	union i2c_smbus_data data;
	s32 ret;

	dev_dbg(&client->dev, "Writing 0x%x to address 0x%x", value, command);

	data.word = 0x0000; /* erase command */
	ret = i2c_smbus_xfer(client->adapter, client->addr,
			     client->flags | I2C_CLIENT_PEC,
			     I2C_SMBUS_WRITE, command,
			     I2C_SMBUS_WORD_DATA, &data);
	if (ret < 0)
		return ret;

	msleep(MLX90614_TIMING_EEPROM);

	data.word = value; /* actual write */
	ret = i2c_smbus_xfer(client->adapter, client->addr,
			     client->flags | I2C_CLIENT_PEC,
			     I2C_SMBUS_WRITE, command,
			     I2C_SMBUS_WORD_DATA, &data);

	msleep(MLX90614_TIMING_EEPROM);

	return ret;
}

/*
 * Find the IIR value inside mlx90614_iir_values array and return its position
 * which is equivalent to the bit value in sensor register
 */
static inline s32 mlx90614_iir_search(const struct i2c_client *client,
				      int value)
{
	int i;
	s32 ret;

	for (i = 0; i < ARRAY_SIZE(mlx90614_iir_values); ++i) {
		if (value == mlx90614_iir_values[i])
			break;
	}

	if (i == ARRAY_SIZE(mlx90614_iir_values))
		return -EINVAL;

	/*
	 * CONFIG register values must not be changed so
	 * we must read them before we actually write
	 * changes
	 */
	ret = i2c_smbus_read_word_data(client, MLX90614_CONFIG);
	if (ret > 0)
		return ret;

	/* Write changed values */
	ret = mlx90614_write_word(client, MLX90614_CONFIG,
			(i << MLX90614_CONFIG_IIR_SHIFT) |
			(((u16) ((0x7 << MLX90614_CONFIG_FIR_SHIFT) |
			((u16) ret & (~((u16) MLX90614_CONFIG_FIR_MASK))))) &
			(~(u16) MLX90614_CONFIG_IIR_MASK)));
	return ret;
}

#ifdef CONFIG_PM
/*
 * If @startup is true, make sure MLX90614_TIMING_STARTUP ms have elapsed since
 * the last wake-up.  This is normally only needed to get a valid temperature
 * reading.  EEPROM access does not need such delay.
 * Return 0 on success, <0 on error.
 */
static int mlx90614_power_get(struct mlx90614_data *data, bool startup)
{
	unsigned long now;

	if (!data->wakeup_gpio)
		return 0;

	pm_runtime_get_sync(&data->client->dev);

	if (startup) {
		now = jiffies;
		if (time_before(now, data->ready_timestamp) &&
		    msleep_interruptible(jiffies_to_msecs(
				data->ready_timestamp - now)) != 0) {
			pm_runtime_put_autosuspend(&data->client->dev);
			return -EINTR;
		}
	}

	return 0;
}

static void mlx90614_power_put(struct mlx90614_data *data)
{
	if (!data->wakeup_gpio)
		return;

	pm_runtime_mark_last_busy(&data->client->dev);
	pm_runtime_put_autosuspend(&data->client->dev);
}
#else
static inline int mlx90614_power_get(struct mlx90614_data *data, bool startup)
{
	return 0;
}

static inline void mlx90614_power_put(struct mlx90614_data *data)
{
}
#endif

static int mlx90614_read_raw(struct iio_dev *indio_dev,
			    struct iio_chan_spec const *channel, int *val,
			    int *val2, long mask)
{
	struct mlx90614_data *data = iio_priv(indio_dev);
	u8 cmd;
	s32 ret;

	switch (mask) {
	case IIO_CHAN_INFO_RAW: /* 0.02K / LSB */
		switch (channel->channel2) {
		case IIO_MOD_TEMP_AMBIENT:
			cmd = MLX90614_TA;
			break;
		case IIO_MOD_TEMP_OBJECT:
			switch (channel->channel) {
			case 0:
				cmd = MLX90614_TOBJ1;
				break;
			case 1:
				cmd = MLX90614_TOBJ2;
				break;
			default:
				return -EINVAL;
			}
			break;
		default:
			return -EINVAL;
		}

		ret = mlx90614_power_get(data, true);
		if (ret < 0)
			return ret;
		ret = i2c_smbus_read_word_data(data->client, cmd);
		mlx90614_power_put(data);

		if (ret < 0)
			return ret;

		/* MSB is an error flag */
		if (ret & 0x8000)
			return -EIO;

		*val = ret;
		return IIO_VAL_INT;
	case IIO_CHAN_INFO_OFFSET:
		*val = MLX90614_CONST_OFFSET_DEC;
		*val2 = MLX90614_CONST_OFFSET_REM;
		return IIO_VAL_INT_PLUS_MICRO;
	case IIO_CHAN_INFO_SCALE:
		*val = MLX90614_CONST_SCALE;
		return IIO_VAL_INT;
	case IIO_CHAN_INFO_CALIBEMISSIVITY: /* 1/65535 / LSB */
		mlx90614_power_get(data, false);
		mutex_lock(&data->lock);
		ret = i2c_smbus_read_word_data(data->client,
					       MLX90614_EMISSIVITY);
		mutex_unlock(&data->lock);
		mlx90614_power_put(data);

		if (ret < 0)
			return ret;

		if (ret == MLX90614_CONST_RAW_EMISSIVITY_MAX) {
			*val = 1;
			*val2 = 0;
		} else {
			*val = 0;
			*val2 = ret * MLX90614_CONST_EMISSIVITY_RESOLUTION;
		}
		return IIO_VAL_INT_PLUS_NANO;
	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: /* IIR setting with
							     FIR = 1024 */
		mlx90614_power_get(data, false);
		mutex_lock(&data->lock);
		ret = i2c_smbus_read_word_data(data->client, MLX90614_CONFIG);
		mutex_unlock(&data->lock);
		mlx90614_power_put(data);

		if (ret < 0)
			return ret;

		*val = mlx90614_iir_values[ret & MLX90614_CONFIG_IIR_MASK] / 100;
		*val2 = (mlx90614_iir_values[ret & MLX90614_CONFIG_IIR_MASK] % 100) *
			10000;
		return IIO_VAL_INT_PLUS_MICRO;
	default:
		return -EINVAL;
	}
}

static int mlx90614_write_raw(struct iio_dev *indio_dev,
			     struct iio_chan_spec const *channel, int val,
			     int val2, long mask)
{
	struct mlx90614_data *data = iio_priv(indio_dev);
	s32 ret;

	switch (mask) {
	case IIO_CHAN_INFO_CALIBEMISSIVITY: /* 1/65535 / LSB */
		if (val < 0 || val2 < 0 || val > 1 || (val == 1 && val2 != 0))
			return -EINVAL;
		val = val * MLX90614_CONST_RAW_EMISSIVITY_MAX +
			val2 / MLX90614_CONST_EMISSIVITY_RESOLUTION;

		mlx90614_power_get(data, false);
		mutex_lock(&data->lock);
		ret = mlx90614_write_word(data->client, MLX90614_EMISSIVITY,
					  val);
		mutex_unlock(&data->lock);
		mlx90614_power_put(data);

		return ret;
	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: /* IIR Filter setting */
		if (val < 0 || val2 < 0)
			return -EINVAL;

		mlx90614_power_get(data, false);
		mutex_lock(&data->lock);
		ret = mlx90614_iir_search(data->client,
					  val * 100 + val2 / 10000);
		mutex_unlock(&data->lock);
		mlx90614_power_put(data);

		return ret;
	default:
		return -EINVAL;
	}
}

static int mlx90614_write_raw_get_fmt(struct iio_dev *indio_dev,
				     struct iio_chan_spec const *channel,
				     long mask)
{
	switch (mask) {
	case IIO_CHAN_INFO_CALIBEMISSIVITY:
		return IIO_VAL_INT_PLUS_NANO;
	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
		return IIO_VAL_INT_PLUS_MICRO;
	default:
		return -EINVAL;
	}
}

static const struct iio_chan_spec mlx90614_channels[] = {
	{
		.type = IIO_TEMP,
		.modified = 1,
		.channel2 = IIO_MOD_TEMP_AMBIENT,
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
		    BIT(IIO_CHAN_INFO_SCALE),
	},
	{
		.type = IIO_TEMP,
		.modified = 1,
		.channel2 = IIO_MOD_TEMP_OBJECT,
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
		    BIT(IIO_CHAN_INFO_CALIBEMISSIVITY) |
			BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
		    BIT(IIO_CHAN_INFO_SCALE),
	},
	{
		.type = IIO_TEMP,
		.indexed = 1,
		.modified = 1,
		.channel = 1,
		.channel2 = IIO_MOD_TEMP_OBJECT,
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
		    BIT(IIO_CHAN_INFO_CALIBEMISSIVITY) |
			BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
		    BIT(IIO_CHAN_INFO_SCALE),
	},
};

static const struct iio_info mlx90614_info = {
	.read_raw = mlx90614_read_raw,
	.write_raw = mlx90614_write_raw,
	.write_raw_get_fmt = mlx90614_write_raw_get_fmt,
	.attrs = &mlx90614_attr_group,
	.driver_module = THIS_MODULE,
};

#ifdef CONFIG_PM
static int mlx90614_sleep(struct mlx90614_data *data)
{
	s32 ret;

	if (!data->wakeup_gpio) {
		dev_dbg(&data->client->dev, "Sleep disabled");
		return -ENOSYS;
	}

	dev_dbg(&data->client->dev, "Requesting sleep");

	mutex_lock(&data->lock);
	ret = i2c_smbus_xfer(data->client->adapter, data->client->addr,
			     data->client->flags | I2C_CLIENT_PEC,
			     I2C_SMBUS_WRITE, MLX90614_OP_SLEEP,
			     I2C_SMBUS_BYTE, NULL);
	mutex_unlock(&data->lock);

	return ret;
}

static int mlx90614_wakeup(struct mlx90614_data *data)
{
	if (!data->wakeup_gpio) {
		dev_dbg(&data->client->dev, "Wake-up disabled");
		return -ENOSYS;
	}

	dev_dbg(&data->client->dev, "Requesting wake-up");

	i2c_lock_adapter(data->client->adapter);
	gpiod_direction_output(data->wakeup_gpio, 0);
	msleep(MLX90614_TIMING_WAKEUP);
	gpiod_direction_input(data->wakeup_gpio);
	i2c_unlock_adapter(data->client->adapter);

	data->ready_timestamp = jiffies +
			msecs_to_jiffies(MLX90614_TIMING_STARTUP);

	/*
	 * Quirk: the i2c controller may get confused right after the
	 * wake-up signal has been sent.  As a workaround, do a dummy read.
	 * If the read fails, the controller will probably be reset so that
	 * further reads will work.
	 */
	i2c_smbus_read_word_data(data->client, MLX90614_CONFIG);

	return 0;
}

/* Return wake-up GPIO or NULL if sleep functionality should be disabled. */
static struct gpio_desc *mlx90614_probe_wakeup(struct i2c_client *client)
{
	struct gpio_desc *gpio;

	if (!i2c_check_functionality(client->adapter,
						I2C_FUNC_SMBUS_WRITE_BYTE)) {
		dev_info(&client->dev,
			 "i2c adapter does not support SMBUS_WRITE_BYTE, sleep disabled");
		return NULL;
	}

	gpio = devm_gpiod_get_optional(&client->dev, "wakeup", GPIOD_IN);

	if (IS_ERR(gpio)) {
		dev_warn(&client->dev,
			 "gpio acquisition failed with error %ld, sleep disabled",
			 PTR_ERR(gpio));
		return NULL;
	} else if (!gpio) {
		dev_info(&client->dev,
			 "wakeup-gpio not found, sleep disabled");
	}

	return gpio;
}
#else
static inline int mlx90614_sleep(struct mlx90614_data *data)
{
	return -ENOSYS;
}
static inline int mlx90614_wakeup(struct mlx90614_data *data)
{
	return -ENOSYS;
}
static inline struct gpio_desc *mlx90614_probe_wakeup(struct i2c_client *client)
{
	return NULL;
}
#endif

/* Return 0 for single sensor, 1 for dual sensor, <0 on error. */
static int mlx90614_probe_num_ir_sensors(struct i2c_client *client)
{
	s32 ret;

	ret = i2c_smbus_read_word_data(client, MLX90614_CONFIG);

	if (ret < 0)
		return ret;

	return (ret & MLX90614_CONFIG_DUAL_MASK) ? 1 : 0;
}

static int mlx90614_probe(struct i2c_client *client,
			 const struct i2c_device_id *id)
{
	struct iio_dev *indio_dev;
	struct mlx90614_data *data;
	int ret;

	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
		return -ENODEV;

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

	data = iio_priv(indio_dev);
	i2c_set_clientdata(client, indio_dev);
	data->client = client;
	mutex_init(&data->lock);
	data->wakeup_gpio = mlx90614_probe_wakeup(client);

	mlx90614_wakeup(data);

	indio_dev->dev.parent = &client->dev;
	indio_dev->name = id->name;
	indio_dev->modes = INDIO_DIRECT_MODE;
	indio_dev->info = &mlx90614_info;

	ret = mlx90614_probe_num_ir_sensors(client);
	switch (ret) {
	case 0:
		dev_dbg(&client->dev, "Found single sensor");
		indio_dev->channels = mlx90614_channels;
		indio_dev->num_channels = 2;
		break;
	case 1:
		dev_dbg(&client->dev, "Found dual sensor");
		indio_dev->channels = mlx90614_channels;
		indio_dev->num_channels = 3;
		break;
	default:
		return ret;
	}

	if (data->wakeup_gpio) {
		pm_runtime_set_autosuspend_delay(&client->dev,
						 MLX90614_AUTOSLEEP_DELAY);
		pm_runtime_use_autosuspend(&client->dev);
		pm_runtime_set_active(&client->dev);
		pm_runtime_enable(&client->dev);
	}

	return iio_device_register(indio_dev);
}

static int mlx90614_remove(struct i2c_client *client)
{
	struct iio_dev *indio_dev = i2c_get_clientdata(client);
	struct mlx90614_data *data = iio_priv(indio_dev);

	iio_device_unregister(indio_dev);

	if (data->wakeup_gpio) {
		pm_runtime_disable(&client->dev);
		if (!pm_runtime_status_suspended(&client->dev))
			mlx90614_sleep(data);
		pm_runtime_set_suspended(&client->dev);
	}

	return 0;
}

static const struct i2c_device_id mlx90614_id[] = {
	{ "mlx90614", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, mlx90614_id);

#ifdef CONFIG_PM_SLEEP
static int mlx90614_pm_suspend(struct device *dev)
{
	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
	struct mlx90614_data *data = iio_priv(indio_dev);

	if (data->wakeup_gpio && pm_runtime_active(dev))
		return mlx90614_sleep(data);

	return 0;
}

static int mlx90614_pm_resume(struct device *dev)
{
	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
	struct mlx90614_data *data = iio_priv(indio_dev);
	int err;

	if (data->wakeup_gpio) {
		err = mlx90614_wakeup(data);
		if (err < 0)
			return err;

		pm_runtime_disable(dev);
		pm_runtime_set_active(dev);
		pm_runtime_enable(dev);
	}

	return 0;
}
#endif

#ifdef CONFIG_PM
static int mlx90614_pm_runtime_suspend(struct device *dev)
{
	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
	struct mlx90614_data *data = iio_priv(indio_dev);

	return mlx90614_sleep(data);
}

static int mlx90614_pm_runtime_resume(struct device *dev)
{
	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
	struct mlx90614_data *data = iio_priv(indio_dev);

	return mlx90614_wakeup(data);
}
#endif

static const struct dev_pm_ops mlx90614_pm_ops = {
	SET_SYSTEM_SLEEP_PM_OPS(mlx90614_pm_suspend, mlx90614_pm_resume)
	SET_RUNTIME_PM_OPS(mlx90614_pm_runtime_suspend,
			   mlx90614_pm_runtime_resume, NULL)
};

static struct i2c_driver mlx90614_driver = {
	.driver = {
		.name	= "mlx90614",
		.pm	= &mlx90614_pm_ops,
	},
	.probe = mlx90614_probe,
	.remove = mlx90614_remove,
	.id_table = mlx90614_id,
};
module_i2c_driver(mlx90614_driver);

MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
MODULE_AUTHOR("Vianney le Clément de Saint-Marcq <vianney.leclement@essensium.com>");
MODULE_AUTHOR("Crt Mori <cmo@melexis.com>");
MODULE_DESCRIPTION("Melexis MLX90614 contactless IR temperature sensor driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
474fe212 PM	1	/*
	2	* mlx90614.c - Support for Melexis MLX90614 contactless IR temperature sensor
	3	*
	4	* Copyright (c) 2014 Peter Meerwald <pmeerw@pmeerw.net>
bad4d1a0	5	* Copyright (c) 2015 Essensium NV
764589b6	6	* Copyright (c) 2015 Melexis
474fe212 PM	7	*
	8	* This file is subject to the terms and conditions of version 2 of
	9	* the GNU General Public License. See the file COPYING in the main
	10	* directory of this archive for more details.
	11	*
	12	* Driver for the Melexis MLX90614 I2C 16-bit IR thermopile sensor
	13	*
	14	* (7-bit I2C slave address 0x5a, 100KHz bus speed only!)
	15	*
eb4b07da VCSM	16	* To wake up from sleep mode, the SDA line must be held low while SCL is high
	17	* for at least 33ms. This is achieved with an extra GPIO that can be connected
	18	* directly to the SDA line. In normal operation, the GPIO is set as input and
	19	* will not interfere in I2C communication. While the GPIO is driven low, the
	20	* i2c adapter is locked since it cannot be used by other clients. The SCL line
	21	* always has a pull-up so we do not need an extra GPIO to drive it high. If
	22	* the "wakeup" GPIO is not given, power management will be disabled.
	23	*
474fe212 PM	24	*/
	25
	26	#include <linux/err.h>
	27	#include <linux/i2c.h>
	28	#include <linux/module.h>
fad65a8f	29	#include <linux/delay.h>
eb4b07da VCSM	30	#include <linux/jiffies.h>
	31	#include <linux/gpio/consumer.h>
	32	#include <linux/pm_runtime.h>
474fe212 PM	33
474fe212 PM	34	#include <linux/iio/iio.h>
764589b6	35	#include <linux/iio/sysfs.h>
474fe212	36
209c0069 VCSM	37	#define MLX90614_OP_RAM 0x00
	38	#define MLX90614_OP_EEPROM 0x20
	39	#define MLX90614_OP_SLEEP 0xff
474fe212 PM	40
474fe212 PM	41	/* RAM offsets with 16-bit data, MSB first */
209c0069 VCSM	42	#define MLX90614_RAW1 (MLX90614_OP_RAM \| 0x04) /* raw data IR channel 1 */
209c0069 VCSM	43	#define MLX90614_RAW2 (MLX90614_OP_RAM \| 0x05) /* raw data IR channel 2 */
c7586584 VCSM	44	#define MLX90614_TA (MLX90614_OP_RAM \| 0x06) /* ambient temperature */
c7586584 VCSM	45	#define MLX90614_TOBJ1 (MLX90614_OP_RAM \| 0x07) /* object 1 temperature */
209c0069 VCSM	46	#define MLX90614_TOBJ2 (MLX90614_OP_RAM \| 0x08) /* object 2 temperature */
	47
	48	/* EEPROM offsets with 16-bit data, MSB first */
	49	#define MLX90614_EMISSIVITY (MLX90614_OP_EEPROM \| 0x04) /* emissivity correction coefficient */
	50	#define MLX90614_CONFIG (MLX90614_OP_EEPROM \| 0x05) /* configuration register */
	51
	52	/* Control bits in configuration register */
	53	#define MLX90614_CONFIG_IIR_SHIFT 0 /* IIR coefficient */
	54	#define MLX90614_CONFIG_IIR_MASK (0x7 << MLX90614_CONFIG_IIR_SHIFT)
	55	#define MLX90614_CONFIG_DUAL_SHIFT 6 /* single (0) or dual (1) IR sensor */
	56	#define MLX90614_CONFIG_DUAL_MASK (1 << MLX90614_CONFIG_DUAL_SHIFT)
	57	#define MLX90614_CONFIG_FIR_SHIFT 8 /* FIR coefficient */
	58	#define MLX90614_CONFIG_FIR_MASK (0x7 << MLX90614_CONFIG_FIR_SHIFT)
	59	#define MLX90614_CONFIG_GAIN_SHIFT 11 /* gain */
	60	#define MLX90614_CONFIG_GAIN_MASK (0x7 << MLX90614_CONFIG_GAIN_SHIFT)
	61
	62	/* Timings (in ms) */
	63	#define MLX90614_TIMING_EEPROM 20 /* time for EEPROM write/erase to complete */
	64	#define MLX90614_TIMING_WAKEUP 34 /* time to hold SDA low for wake-up */
	65	#define MLX90614_TIMING_STARTUP 250 /* time before first data after wake-up */
474fe212	66
eb4b07da VCSM	67	#define MLX90614_AUTOSLEEP_DELAY 5000 /* default autosleep delay */
eb4b07da VCSM	68
f9ba1ab4 CM	69	/* Magic constants */
	70	#define MLX90614_CONST_OFFSET_DEC -13657 /* decimal part of the Kelvin offset */
	71	#define MLX90614_CONST_OFFSET_REM 500000 /* remainder of offset (273.1550) /
	72	#define MLX90614_CONST_SCALE 20 /* Scale in milliKelvin (0.02 * 1000) */
	73	#define MLX90614_CONST_RAW_EMISSIVITY_MAX 65535 /* max value for emissivity */
	74	#define MLX90614_CONST_EMISSIVITY_RESOLUTION 15259 /* 1/65535 ~ 0.000015259 */
	75
474fe212 PM	76	struct mlx90614_data {
474fe212 PM	77	struct i2c_client *client;
fad65a8f	78	struct mutex lock; /* for EEPROM access only */
eb4b07da VCSM	79	struct gpio_desc wakeup_gpio; / NULL to disable sleep/wake-up */
eb4b07da VCSM	80	unsigned long ready_timestamp; /* in jiffies */
474fe212 PM	81	};
474fe212 PM	82
764589b6 CM	83	/* Bandwidth values for IIR filtering */
	84	static const int mlx90614_iir_values[] = {77, 31, 20, 15, 723, 153, 110, 86};
	85	static IIO_CONST_ATTR(in_temp_object_filter_low_pass_3db_frequency_available,
	86	"0.15 0.20 0.31 0.77 0.86 1.10 1.53 7.23");
	87
	88	static struct attribute *mlx90614_attributes[] = {
	89	&iio_const_attr_in_temp_object_filter_low_pass_3db_frequency_available.dev_attr.attr,
	90	NULL,
	91	};
	92
	93	static const struct attribute_group mlx90614_attr_group = {
	94	.attrs = mlx90614_attributes,
	95	};
	96
fad65a8f VCSM	97	/*
	98	* Erase an address and write word.
	99	* The mutex must be locked before calling.
	100	*/
	101	static s32 mlx90614_write_word(const struct i2c_client *client, u8 command,
	102	u16 value)
	103	{
	104	/*
	105	* Note: The mlx90614 requires a PEC on writing but does not send us a
	106	* valid PEC on reading. Hence, we cannot set I2C_CLIENT_PEC in
	107	* i2c_client.flags. As a workaround, we use i2c_smbus_xfer here.
	108	*/
	109	union i2c_smbus_data data;
	110	s32 ret;
	111
	112	dev_dbg(&client->dev, "Writing 0x%x to address 0x%x", value, command);
	113
	114	data.word = 0x0000; /* erase command */
	115	ret = i2c_smbus_xfer(client->adapter, client->addr,
	116	client->flags \| I2C_CLIENT_PEC,
	117	I2C_SMBUS_WRITE, command,
	118	I2C_SMBUS_WORD_DATA, &data);
	119	if (ret < 0)
	120	return ret;
	121
	122	msleep(MLX90614_TIMING_EEPROM);
	123
	124	data.word = value; /* actual write */
	125	ret = i2c_smbus_xfer(client->adapter, client->addr,
	126	client->flags \| I2C_CLIENT_PEC,
	127	I2C_SMBUS_WRITE, command,
	128	I2C_SMBUS_WORD_DATA, &data);
	129
	130	msleep(MLX90614_TIMING_EEPROM);
	131
	132	return ret;
	133	}
	134
764589b6 CM	135	/*
	136	* Find the IIR value inside mlx90614_iir_values array and return its position
	137	* which is equivalent to the bit value in sensor register
	138	*/
	139	static inline s32 mlx90614_iir_search(const struct i2c_client *client,
	140	int value)
	141	{
	142	int i;
	143	s32 ret;
	144
	145	for (i = 0; i < ARRAY_SIZE(mlx90614_iir_values); ++i) {
	146	if (value == mlx90614_iir_values[i])
	147	break;
	148	}
	149
	150	if (i == ARRAY_SIZE(mlx90614_iir_values))
	151	return -EINVAL;
	152
	153	/*
	154	* CONFIG register values must not be changed so
	155	* we must read them before we actually write
	156	* changes
	157	*/
	158	ret = i2c_smbus_read_word_data(client, MLX90614_CONFIG);
	159	if (ret > 0)
	160	return ret;
	161
	162	/* Write changed values */
	163	ret = mlx90614_write_word(client, MLX90614_CONFIG,
	164	(i << MLX90614_CONFIG_IIR_SHIFT) \|
	165	(((u16) ((0x7 << MLX90614_CONFIG_FIR_SHIFT) \|
	166	((u16) ret & (~((u16) MLX90614_CONFIG_FIR_MASK))))) &
	167	(~(u16) MLX90614_CONFIG_IIR_MASK)));
	168	return ret;
	169	}
	170
eb4b07da VCSM	171	#ifdef CONFIG_PM
	172	/*
	173	* If @startup is true, make sure MLX90614_TIMING_STARTUP ms have elapsed since
	174	* the last wake-up. This is normally only needed to get a valid temperature
	175	* reading. EEPROM access does not need such delay.
	176	* Return 0 on success, <0 on error.
	177	*/
	178	static int mlx90614_power_get(struct mlx90614_data *data, bool startup)
	179	{
	180	unsigned long now;
	181
	182	if (!data->wakeup_gpio)
	183	return 0;
	184
	185	pm_runtime_get_sync(&data->client->dev);
	186
	187	if (startup) {
	188	now = jiffies;
	189	if (time_before(now, data->ready_timestamp) &&
	190	msleep_interruptible(jiffies_to_msecs(
	191	data->ready_timestamp - now)) != 0) {
	192	pm_runtime_put_autosuspend(&data->client->dev);
	193	return -EINTR;
	194	}
	195	}
	196
	197	return 0;
	198	}
	199
	200	static void mlx90614_power_put(struct mlx90614_data *data)
	201	{
	202	if (!data->wakeup_gpio)
	203	return;
	204
	205	pm_runtime_mark_last_busy(&data->client->dev);
	206	pm_runtime_put_autosuspend(&data->client->dev);
	207	}
	208	#else
	209	static inline int mlx90614_power_get(struct mlx90614_data *data, bool startup)
	210	{
	211	return 0;
	212	}
	213
	214	static inline void mlx90614_power_put(struct mlx90614_data *data)
	215	{
	216	}
	217	#endif
	218
474fe212 PM	219	static int mlx90614_read_raw(struct iio_dev *indio_dev,
	220	struct iio_chan_spec const channel, int val,
	221	int *val2, long mask)
	222	{
	223	struct mlx90614_data *data = iio_priv(indio_dev);
bad4d1a0	224	u8 cmd;
474fe212 PM	225	s32 ret;
	226
	227	switch (mask) {
	228	case IIO_CHAN_INFO_RAW: /* 0.02K / LSB */
	229	switch (channel->channel2) {
	230	case IIO_MOD_TEMP_AMBIENT:
bad4d1a0	231	cmd = MLX90614_TA;
474fe212 PM	232	break;
474fe212 PM	233	case IIO_MOD_TEMP_OBJECT:
bad4d1a0 VCSM	234	switch (channel->channel) {
	235	case 0:
	236	cmd = MLX90614_TOBJ1;
	237	break;
	238	case 1:
	239	cmd = MLX90614_TOBJ2;
	240	break;
	241	default:
	242	return -EINVAL;
	243	}
474fe212 PM	244	break;
	245	default:
	246	return -EINVAL;
	247	}
bad4d1a0	248
eb4b07da VCSM	249	ret = mlx90614_power_get(data, true);
	250	if (ret < 0)
	251	return ret;
bad4d1a0	252	ret = i2c_smbus_read_word_data(data->client, cmd);
eb4b07da VCSM	253	mlx90614_power_put(data);
eb4b07da VCSM	254
bad4d1a0 VCSM	255	if (ret < 0)
bad4d1a0 VCSM	256	return ret;
d02e0f8f VCSM	257
	258	/* MSB is an error flag */
	259	if (ret & 0x8000)
	260	return -EIO;
	261
474fe212 PM	262	*val = ret;
	263	return IIO_VAL_INT;
	264	case IIO_CHAN_INFO_OFFSET:
f9ba1ab4 CM	265	*val = MLX90614_CONST_OFFSET_DEC;
f9ba1ab4 CM	266	*val2 = MLX90614_CONST_OFFSET_REM;
474fe212 PM	267	return IIO_VAL_INT_PLUS_MICRO;
474fe212 PM	268	case IIO_CHAN_INFO_SCALE:
f9ba1ab4	269	*val = MLX90614_CONST_SCALE;
474fe212	270	return IIO_VAL_INT;
fad65a8f	271	case IIO_CHAN_INFO_CALIBEMISSIVITY: /* 1/65535 / LSB */
eb4b07da	272	mlx90614_power_get(data, false);
fad65a8f VCSM	273	mutex_lock(&data->lock);
	274	ret = i2c_smbus_read_word_data(data->client,
	275	MLX90614_EMISSIVITY);
	276	mutex_unlock(&data->lock);
eb4b07da	277	mlx90614_power_put(data);
fad65a8f VCSM	278
	279	if (ret < 0)
	280	return ret;
	281
f9ba1ab4	282	if (ret == MLX90614_CONST_RAW_EMISSIVITY_MAX) {
fad65a8f VCSM	283	*val = 1;
	284	*val2 = 0;
	285	} else {
	286	*val = 0;
f9ba1ab4	287	val2 = ret MLX90614_CONST_EMISSIVITY_RESOLUTION;
fad65a8f VCSM	288	}
fad65a8f VCSM	289	return IIO_VAL_INT_PLUS_NANO;
764589b6 CM	290	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: /* IIR setting with
	291	FIR = 1024 */
	292	mlx90614_power_get(data, false);
	293	mutex_lock(&data->lock);
	294	ret = i2c_smbus_read_word_data(data->client, MLX90614_CONFIG);
	295	mutex_unlock(&data->lock);
	296	mlx90614_power_put(data);
	297
	298	if (ret < 0)
	299	return ret;
	300
	301	*val = mlx90614_iir_values[ret & MLX90614_CONFIG_IIR_MASK] / 100;
	302	val2 = (mlx90614_iir_values[ret & MLX90614_CONFIG_IIR_MASK] % 100)
	303	10000;
	304	return IIO_VAL_INT_PLUS_MICRO;
fad65a8f VCSM	305	default:
	306	return -EINVAL;
	307	}
	308	}
	309
	310	static int mlx90614_write_raw(struct iio_dev *indio_dev,
	311	struct iio_chan_spec const *channel, int val,
	312	int val2, long mask)
	313	{
	314	struct mlx90614_data *data = iio_priv(indio_dev);
	315	s32 ret;
	316
	317	switch (mask) {
	318	case IIO_CHAN_INFO_CALIBEMISSIVITY: /* 1/65535 / LSB */
	319	if (val < 0 \|\| val2 < 0 \|\| val > 1 \|\| (val == 1 && val2 != 0))
	320	return -EINVAL;
f9ba1ab4 CM	321	val = val * MLX90614_CONST_RAW_EMISSIVITY_MAX +
f9ba1ab4 CM	322	val2 / MLX90614_CONST_EMISSIVITY_RESOLUTION;
fad65a8f	323
eb4b07da	324	mlx90614_power_get(data, false);
fad65a8f VCSM	325	mutex_lock(&data->lock);
	326	ret = mlx90614_write_word(data->client, MLX90614_EMISSIVITY,
	327	val);
	328	mutex_unlock(&data->lock);
eb4b07da	329	mlx90614_power_put(data);
fad65a8f	330
764589b6 CM	331	return ret;
	332	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: /* IIR Filter setting */
	333	if (val < 0 \|\| val2 < 0)
	334	return -EINVAL;
	335
	336	mlx90614_power_get(data, false);
	337	mutex_lock(&data->lock);
	338	ret = mlx90614_iir_search(data->client,
	339	val * 100 + val2 / 10000);
	340	mutex_unlock(&data->lock);
	341	mlx90614_power_put(data);
	342
f2c714a0	343	return ret;
fad65a8f VCSM	344	default:
	345	return -EINVAL;
	346	}
	347	}
	348
	349	static int mlx90614_write_raw_get_fmt(struct iio_dev *indio_dev,
6069f47f	350	struct iio_chan_spec const *channel,
fad65a8f VCSM	351	long mask)
	352	{
	353	switch (mask) {
	354	case IIO_CHAN_INFO_CALIBEMISSIVITY:
	355	return IIO_VAL_INT_PLUS_NANO;
764589b6 CM	356	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
764589b6 CM	357	return IIO_VAL_INT_PLUS_MICRO;
474fe212 PM	358	default:
	359	return -EINVAL;
	360	}
	361	}
	362
	363	static const struct iio_chan_spec mlx90614_channels[] = {
	364	{
	365	.type = IIO_TEMP,
	366	.modified = 1,
	367	.channel2 = IIO_MOD_TEMP_AMBIENT,
	368	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
	369	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) \|
	370	BIT(IIO_CHAN_INFO_SCALE),
	371	},
	372	{
	373	.type = IIO_TEMP,
	374	.modified = 1,
	375	.channel2 = IIO_MOD_TEMP_OBJECT,
fad65a8f	376	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) \|
764589b6 CM	377	BIT(IIO_CHAN_INFO_CALIBEMISSIVITY) \|
764589b6 CM	378	BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
474fe212 PM	379	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) \|
	380	BIT(IIO_CHAN_INFO_SCALE),
	381	},
bad4d1a0 VCSM	382	{
	383	.type = IIO_TEMP,
	384	.indexed = 1,
	385	.modified = 1,
	386	.channel = 1,
	387	.channel2 = IIO_MOD_TEMP_OBJECT,
fad65a8f	388	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) \|
764589b6 CM	389	BIT(IIO_CHAN_INFO_CALIBEMISSIVITY) \|
764589b6 CM	390	BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
bad4d1a0 VCSM	391	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) \|
	392	BIT(IIO_CHAN_INFO_SCALE),
	393	},
474fe212 PM	394	};
	395
	396	static const struct iio_info mlx90614_info = {
	397	.read_raw = mlx90614_read_raw,
fad65a8f VCSM	398	.write_raw = mlx90614_write_raw,
fad65a8f VCSM	399	.write_raw_get_fmt = mlx90614_write_raw_get_fmt,
764589b6	400	.attrs = &mlx90614_attr_group,
474fe212 PM	401	.driver_module = THIS_MODULE,
	402	};
	403
eb4b07da VCSM	404	#ifdef CONFIG_PM
	405	static int mlx90614_sleep(struct mlx90614_data *data)
	406	{
	407	s32 ret;
	408
	409	if (!data->wakeup_gpio) {
	410	dev_dbg(&data->client->dev, "Sleep disabled");
	411	return -ENOSYS;
	412	}
	413
	414	dev_dbg(&data->client->dev, "Requesting sleep");
	415
	416	mutex_lock(&data->lock);
	417	ret = i2c_smbus_xfer(data->client->adapter, data->client->addr,
	418	data->client->flags \| I2C_CLIENT_PEC,
	419	I2C_SMBUS_WRITE, MLX90614_OP_SLEEP,
	420	I2C_SMBUS_BYTE, NULL);
	421	mutex_unlock(&data->lock);
	422
	423	return ret;
	424	}
	425
	426	static int mlx90614_wakeup(struct mlx90614_data *data)
	427	{
	428	if (!data->wakeup_gpio) {
	429	dev_dbg(&data->client->dev, "Wake-up disabled");
	430	return -ENOSYS;
	431	}
	432
	433	dev_dbg(&data->client->dev, "Requesting wake-up");
	434
	435	i2c_lock_adapter(data->client->adapter);
	436	gpiod_direction_output(data->wakeup_gpio, 0);
	437	msleep(MLX90614_TIMING_WAKEUP);
	438	gpiod_direction_input(data->wakeup_gpio);
	439	i2c_unlock_adapter(data->client->adapter);
	440
	441	data->ready_timestamp = jiffies +
	442	msecs_to_jiffies(MLX90614_TIMING_STARTUP);
	443
	444	/*
	445	* Quirk: the i2c controller may get confused right after the
	446	* wake-up signal has been sent. As a workaround, do a dummy read.
	447	* If the read fails, the controller will probably be reset so that
	448	* further reads will work.
	449	*/
	450	i2c_smbus_read_word_data(data->client, MLX90614_CONFIG);
	451
	452	return 0;
	453	}
	454
	455	/* Return wake-up GPIO or NULL if sleep functionality should be disabled. */
	456	static struct gpio_desc mlx90614_probe_wakeup(struct i2c_client client)
	457	{
	458	struct gpio_desc *gpio;
	459
	460	if (!i2c_check_functionality(client->adapter,
	461	I2C_FUNC_SMBUS_WRITE_BYTE)) {
	462	dev_info(&client->dev,
	463	"i2c adapter does not support SMBUS_WRITE_BYTE, sleep disabled");
	464	return NULL;
	465	}
	466
	467	gpio = devm_gpiod_get_optional(&client->dev, "wakeup", GPIOD_IN);
468
469	if (IS_ERR(gpio)) {
470	dev_warn(&client->dev,
471	"gpio acquisition failed with error %ld, sleep disabled",
472	PTR_ERR(gpio));
473	return NULL;
474	} else if (!gpio) {
475	dev_info(&client->dev,
476	"wakeup-gpio not found, sleep disabled");
477	}
478
479	return gpio;
480	}
481	#else
482	static inline int mlx90614_sleep(struct mlx90614_data *data)
483	{
484	return -ENOSYS;
485	}
486	static inline int mlx90614_wakeup(struct mlx90614_data *data)
487	{
488	return -ENOSYS;
489	}
490	static inline struct gpio_desc mlx90614_probe_wakeup(struct i2c_client client)
491	{
492	return NULL;
493	}
494	#endif
495
bad4d1a0 VCSM	496	/* Return 0 for single sensor, 1 for dual sensor, <0 on error. */
	497	static int mlx90614_probe_num_ir_sensors(struct i2c_client *client)
	498	{
	499	s32 ret;
	500
	501	ret = i2c_smbus_read_word_data(client, MLX90614_CONFIG);
	502
	503	if (ret < 0)
	504	return ret;
	505
	506	return (ret & MLX90614_CONFIG_DUAL_MASK) ? 1 : 0;
	507	}
	508
474fe212 PM	509	static int mlx90614_probe(struct i2c_client *client,
	510	const struct i2c_device_id *id)
	511	{
	512	struct iio_dev *indio_dev;
	513	struct mlx90614_data *data;
bad4d1a0	514	int ret;
474fe212 PM	515
	516	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
	517	return -ENODEV;
	518
	519	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
	520	if (!indio_dev)
	521	return -ENOMEM;
	522
	523	data = iio_priv(indio_dev);
	524	i2c_set_clientdata(client, indio_dev);
	525	data->client = client;
fad65a8f	526	mutex_init(&data->lock);
eb4b07da VCSM	527	data->wakeup_gpio = mlx90614_probe_wakeup(client);
	528
	529	mlx90614_wakeup(data);
474fe212 PM	530
	531	indio_dev->dev.parent = &client->dev;
	532	indio_dev->name = id->name;
	533	indio_dev->modes = INDIO_DIRECT_MODE;
	534	indio_dev->info = &mlx90614_info;
	535
bad4d1a0 VCSM	536	ret = mlx90614_probe_num_ir_sensors(client);
	537	switch (ret) {
	538	case 0:
	539	dev_dbg(&client->dev, "Found single sensor");
	540	indio_dev->channels = mlx90614_channels;
	541	indio_dev->num_channels = 2;
	542	break;
	543	case 1:
	544	dev_dbg(&client->dev, "Found dual sensor");
	545	indio_dev->channels = mlx90614_channels;
	546	indio_dev->num_channels = 3;
	547	break;
	548	default:
	549	return ret;
	550	}
474fe212	551
eb4b07da VCSM	552	if (data->wakeup_gpio) {
	553	pm_runtime_set_autosuspend_delay(&client->dev,
	554	MLX90614_AUTOSLEEP_DELAY);
	555	pm_runtime_use_autosuspend(&client->dev);
	556	pm_runtime_set_active(&client->dev);
	557	pm_runtime_enable(&client->dev);
	558	}
	559
474fe212 PM	560	return iio_device_register(indio_dev);
	561	}
	562
	563	static int mlx90614_remove(struct i2c_client *client)
	564	{
eb4b07da VCSM	565	struct iio_dev *indio_dev = i2c_get_clientdata(client);
	566	struct mlx90614_data *data = iio_priv(indio_dev);
	567
	568	iio_device_unregister(indio_dev);
	569
	570	if (data->wakeup_gpio) {
	571	pm_runtime_disable(&client->dev);
	572	if (!pm_runtime_status_suspended(&client->dev))
	573	mlx90614_sleep(data);
	574	pm_runtime_set_suspended(&client->dev);
	575	}
474fe212 PM	576
	577	return 0;
	578	}
	579
	580	static const struct i2c_device_id mlx90614_id[] = {
	581	{ "mlx90614", 0 },
	582	{ }
	583	};
	584	MODULE_DEVICE_TABLE(i2c, mlx90614_id);
	585
eb4b07da VCSM	586	#ifdef CONFIG_PM_SLEEP
	587	static int mlx90614_pm_suspend(struct device *dev)
	588	{
	589	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
	590	struct mlx90614_data *data = iio_priv(indio_dev);
	591
	592	if (data->wakeup_gpio && pm_runtime_active(dev))
	593	return mlx90614_sleep(data);
	594
	595	return 0;
	596	}
	597
	598	static int mlx90614_pm_resume(struct device *dev)
	599	{
	600	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
	601	struct mlx90614_data *data = iio_priv(indio_dev);
	602	int err;
	603
	604	if (data->wakeup_gpio) {
	605	err = mlx90614_wakeup(data);
	606	if (err < 0)
	607	return err;
	608
	609	pm_runtime_disable(dev);
	610	pm_runtime_set_active(dev);
	611	pm_runtime_enable(dev);
	612	}
	613
	614	return 0;
	615	}
	616	#endif
	617
	618	#ifdef CONFIG_PM
	619	static int mlx90614_pm_runtime_suspend(struct device *dev)
	620	{
	621	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
	622	struct mlx90614_data *data = iio_priv(indio_dev);
	623
	624	return mlx90614_sleep(data);
	625	}
	626
	627	static int mlx90614_pm_runtime_resume(struct device *dev)
	628	{
	629	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
	630	struct mlx90614_data *data = iio_priv(indio_dev);
	631
	632	return mlx90614_wakeup(data);
	633	}
	634	#endif
	635
	636	static const struct dev_pm_ops mlx90614_pm_ops = {
	637	SET_SYSTEM_SLEEP_PM_OPS(mlx90614_pm_suspend, mlx90614_pm_resume)
	638	SET_RUNTIME_PM_OPS(mlx90614_pm_runtime_suspend,
	639	mlx90614_pm_runtime_resume, NULL)
	640	};
	641
474fe212 PM	642	static struct i2c_driver mlx90614_driver = {
	643	.driver = {
	644	.name = "mlx90614",
eb4b07da	645	.pm = &mlx90614_pm_ops,
474fe212 PM	646	},
	647	.probe = mlx90614_probe,
	648	.remove = mlx90614_remove,
	649	.id_table = mlx90614_id,
	650	};
	651	module_i2c_driver(mlx90614_driver);
	652
	653	MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
bad4d1a0	654	MODULE_AUTHOR("Vianney le Clément de Saint-Marcq <vianney.leclement@essensium.com>");
764589b6	655	MODULE_AUTHOR("Crt Mori <cmo@melexis.com>");
474fe212 PM	656	MODULE_DESCRIPTION("Melexis MLX90614 contactless IR temperature sensor driver");
474fe212 PM	657	MODULE_LICENSE("GPL");