diff options
Diffstat (limited to 'drivers/iio/temperature/mlx90614.c')
| -rw-r--r-- | drivers/iio/temperature/mlx90614.c | 150 | 
1 files changed, 150 insertions, 0 deletions
diff --git a/drivers/iio/temperature/mlx90614.c b/drivers/iio/temperature/mlx90614.c new file mode 100644 index 00000000000..c8b6ac8b2d6 --- /dev/null +++ b/drivers/iio/temperature/mlx90614.c @@ -0,0 +1,150 @@ +/* + * mlx90614.c - Support for Melexis MLX90614 contactless IR temperature sensor + * + * Copyright (c) 2014 Peter Meerwald <pmeerw@pmeerw.net> + * + * 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!) + * + * TODO: sleep mode, configuration EEPROM + */ + +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/module.h> + +#include <linux/iio/iio.h> + +#define MLX90614_OP_RAM 0x00 + +/* RAM offsets with 16-bit data, MSB first */ +#define MLX90614_TA 0x06 /* ambient temperature */ +#define MLX90614_TOBJ1 0x07 /* object temperature */ + +struct mlx90614_data { +	struct i2c_client *client; +}; + +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); +	s32 ret; + +	switch (mask) { +	case IIO_CHAN_INFO_RAW: /* 0.02K / LSB */ +		switch (channel->channel2) { +		case IIO_MOD_TEMP_AMBIENT: +			ret = i2c_smbus_read_word_data(data->client, +			    MLX90614_OP_RAM | MLX90614_TA); +			if (ret < 0) +				return ret; +			break; +		case IIO_MOD_TEMP_OBJECT: +			ret = i2c_smbus_read_word_data(data->client, +			    MLX90614_OP_RAM | MLX90614_TOBJ1); +			if (ret < 0) +				return ret; +			break; +		default: +			return -EINVAL; +		} +		*val = ret; +		return IIO_VAL_INT; +	case IIO_CHAN_INFO_OFFSET: +		*val = 13657; +		*val2 = 500000; +		return IIO_VAL_INT_PLUS_MICRO; +	case IIO_CHAN_INFO_SCALE: +		*val = 20; +		return IIO_VAL_INT; +	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), +		.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, +	.driver_module = THIS_MODULE, +}; + +static int mlx90614_probe(struct i2c_client *client, +			 const struct i2c_device_id *id) +{ +	struct iio_dev *indio_dev; +	struct mlx90614_data *data; + +	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; + +	indio_dev->dev.parent = &client->dev; +	indio_dev->name = id->name; +	indio_dev->modes = INDIO_DIRECT_MODE; +	indio_dev->info = &mlx90614_info; + +	indio_dev->channels = mlx90614_channels; +	indio_dev->num_channels = ARRAY_SIZE(mlx90614_channels); + +	return iio_device_register(indio_dev); +} + +static int mlx90614_remove(struct i2c_client *client) +{ +	iio_device_unregister(i2c_get_clientdata(client)); + +	return 0; +} + +static const struct i2c_device_id mlx90614_id[] = { +	{ "mlx90614", 0 }, +	{ } +}; +MODULE_DEVICE_TABLE(i2c, mlx90614_id); + +static struct i2c_driver mlx90614_driver = { +	.driver = { +		.name	= "mlx90614", +		.owner	= THIS_MODULE, +	}, +	.probe = mlx90614_probe, +	.remove = mlx90614_remove, +	.id_table = mlx90614_id, +}; +module_i2c_driver(mlx90614_driver); + +MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>"); +MODULE_DESCRIPTION("Melexis MLX90614 contactless IR temperature sensor driver"); +MODULE_LICENSE("GPL");  | 
