Re: [PATCH] iio: Add TH06 Humidity and Temperature sensor driver

[Peter Meerwald-Stadler]

> Add implementation for Hoperf TH06 Humidity and Temperature
> sensor driver.
> 
> Datasheet: http://www.hoperf.com/upload/sensor/TH06_Module_v01.pdf

I think it would be good to make to manufacturer's company name (Hoperf) 
more visible in the driver; it is currently just mentioned in the commit 
message; just 'TH06' is hard to google :)

maybe you could list the TODOs / unsupported features here...

the I2C register layout looks close to the si7020, maybe the chip can be 
supported there without duplicating code?

minor comments below
 
> Signed-off-by: Cristina Moraru <cristina.moraru09@xxxxxxxxx>
> ---
>  drivers/iio/humidity/Kconfig  |  10 +++
>  drivers/iio/humidity/Makefile |   1 +
>  drivers/iio/humidity/th06.c   | 147 ++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 158 insertions(+)
>  create mode 100644 drivers/iio/humidity/th06.c
> 
> diff --git a/drivers/iio/humidity/Kconfig b/drivers/iio/humidity/Kconfig
> index 6a23698..b233b16 100644
> --- a/drivers/iio/humidity/Kconfig
> +++ b/drivers/iio/humidity/Kconfig
> @@ -55,4 +55,14 @@ config SI7020
>  	  To compile this driver as a module, choose M here: the module
>  	  will be called si7020.
>  
> +config TH06
> +        tristate "TH06 humidity and temperature sensor"
> +        depends on I2C
> +        help
> +          Say yes here to build support for the TH06 measurement of
> +          relative humidity and temperature.
> +
> +          To compile this driver as a module, choose M here: the module
> +          will be called th06.
> +
>  endmenu
> diff --git a/drivers/iio/humidity/Makefile b/drivers/iio/humidity/Makefile
> index c9f089a..3667ee7 100644
> --- a/drivers/iio/humidity/Makefile
> +++ b/drivers/iio/humidity/Makefile
> @@ -7,3 +7,4 @@ obj-$(CONFIG_HDC100X) += hdc100x.o
>  obj-$(CONFIG_HTU21) += htu21.o
>  obj-$(CONFIG_SI7005) += si7005.o
>  obj-$(CONFIG_SI7020) += si7020.o
> +obj-$(CONFIG_TH06) += th06.o
> diff --git a/drivers/iio/humidity/th06.c b/drivers/iio/humidity/th06.c
> new file mode 100644
> index 0000000..44b0d77
> --- /dev/null
> +++ b/drivers/iio/humidity/th06.c
> @@ -0,0 +1,147 @@
> +/*
> + * TH06 - I2C Humidity and Temperature Sensor
> + *
> + * Copyright (C) 2016 Cristina Moraru <cristina.moraru09@xxxxxxxxx>
> + *
> + * 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.
> + *
> + * IIO driver for TH06 (7-bit I2C slave address 0x40)
> + *
> + */
> +
> +#include <linux/module.h>
> +#include <linux/init.h>
> +#include <linux/i2c.h>
> +#include <linux/iio/iio.h>
> +#include <linux/iio/sysfs.h>
> +
> +#define TH06_DRV_NAME		"th06"
> +
> +#define TH06_READ_RH		0xE5
> +#define TH06_READ_TEMP		0xE3
> +
> +struct th06_data {
> +	struct i2c_client *client;
> +};
> +
> +static const struct iio_chan_spec th06_channels[] = {
> +	{
> +		.type	= IIO_HUMIDITYRELATIVE,
> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> +					BIT(IIO_CHAN_INFO_SCALE) |
> +					BIT(IIO_CHAN_INFO_OFFSET),
> +	},
> +	{
> +		.type	= IIO_TEMP,
> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> +					BIT(IIO_CHAN_INFO_SCALE) |
> +					BIT(IIO_CHAN_INFO_OFFSET),
> +	}
> +};
> +
> +static int th06_read_raw(struct iio_dev *indio_dev,
> +			    struct iio_chan_spec const *chan, int *val,
> +			    int *val2, long mask)
> +{
> +	struct th06_data *data = iio_priv(indio_dev);
> +	int ret = -EINVAL;
> +
> +	switch (mask) {
> +	case IIO_CHAN_INFO_RAW:
> +		switch (chan->type) {
> +		case IIO_HUMIDITYRELATIVE:
> +			ret = i2c_smbus_read_word_swapped(data->client,
> +							TH06_READ_RH);
> +			break;
> +		case IIO_TEMP:
> +			ret = i2c_smbus_read_word_swapped(data->client,
> +							TH06_READ_TEMP);
> +			break;
> +		default:
> +			break;
> +		}
> +		if (ret < 0)
> +			return ret;
> +		*val = ret;
> +		return IIO_VAL_INT;
> +	case IIO_CHAN_INFO_SCALE:
> +		switch (chan->type) {
> +		case IIO_HUMIDITYRELATIVE:
> +			*val = 0;
> +			*val2 = 1907349;
> +			break;
> +		case IIO_TEMP:
> +			*val = 0;
> +			*val2 = 2681274;
> +			break;
> +		default:
> +			break;

this doesn't look right, should result in an error if this is ever called, 
similar for offset below

> +		}
> +		return IIO_VAL_INT_PLUS_NANO;
> +	case IIO_CHAN_INFO_OFFSET:
> +		switch (chan->type) {
> +		case IIO_HUMIDITYRELATIVE:
> +			*val = -6;
> +			return IIO_VAL_INT;
> +		case IIO_TEMP:
> +			*val = -46;
> +			*val2 = 850000;
> +			return IIO_VAL_INT_PLUS_MICRO;
> +		default:
> +			break;
> +		}
> +	}
> +	return ret;
> +}
> +
> +
> +static const struct iio_info th06_info = {
> +	.driver_module	= THIS_MODULE,
> +	.read_raw	= th06_read_raw,
> +};
> +
> +static int th06_probe(struct i2c_client *client,
> +			 const struct i2c_device_id *id)
> +{
> +	struct th06_data *data;
> +	struct iio_dev *indio_dev;
> +
> +	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->info = &th06_info;
> +	indio_dev->name = TH06_DRV_NAME;
> +	indio_dev->channels = th06_channels;
> +	indio_dev->num_channels = ARRAY_SIZE(th06_channels);
> +	indio_dev->modes = INDIO_DIRECT_MODE;
> +
> +	return devm_iio_device_register(&client->dev, indio_dev);
> +}
> +
> +static const struct i2c_device_id th06_id[] = {
> +	{"th06", 0},
> +	{}
> +};
> +MODULE_DEVICE_TABLE(i2c, th06_id);
> +
> +static struct i2c_driver th06_driver = {
> +	.driver = {
> +		.name = TH06_DRV_NAME,
> +	},
> +	.probe		= th06_probe,
> +	.id_table	= th06_id,
> +};
> +
> +module_i2c_driver(th06_driver);
> +
> +MODULE_AUTHOR("Cristina Moraru <cristina.moraru09@xxxxxxxxx>");
> +MODULE_DESCRIPTION("TH06 Humidity and Temperature Sensor");
> +MODULE_LICENSE("GPL");
> 

-- 

Peter Meerwald-Stadler
+43-664-2444418 (mobile)