[lm-sensors] [PATCH v2] hwmon: Honeywell Humidicon HIH-6130/HIH-6131 humidity and temperature sensor driver

Guenter Roeck linux at roeck-us.net
Fri Jun 22 17:34:11 CEST 2012


On Fri, Jun 22, 2012 at 12:42:10PM +0000, Iain Paton wrote:
> Hi,
> 
> This is a new driver for the Honeywell Humidicon HIH-6130/HIH-6131 humidity sensor.
> 
> The driver is based on the existing Sensiron sht21 driver with the necessary changes 
> to the probe, update_measurements and conversion functions necessary to use the 
> Honeywell sensors.
> 
> There's no difference between the 6130 & 6131 other than the 6131 having an external 
> condensation filter attached.
> 
> 
> Changed for v2:
> renamed driver to hih6130
> added Documentation/hwmon/hih6130
> calcuations now use DIV_ROUND_CLOSEST and shouldn't cause 32bit int overflow
> addressed other minor review comments
> 
> addressing the alignment concern for the hih6130_show_temperature function gives 
> me an 82 char line and a checkpatch fail, I've left it that way for now as there's a
> couple of other things I'm not sure about, so I think there'll be at least another 
> version of this anyway.
> 
Hi Iain,

almost there.

Please put the above comments after a -- line, and the Signed-off before that.
This way I don't have to manually remove it before integration.

> Signed-off-by: Iain Paton <ipaton0 at gmail.com>
> 
> diff --git a/Documentation/hwmon/hih6130 b/Documentation/hwmon/hih6130
> new file mode 100644
> index 0000000..2958648
> --- /dev/null
> +++ b/Documentation/hwmon/hih6130
> @@ -0,0 +1,34 @@
> +Kernel driver hih6130
> +=====================
> +
> +Supported chips:
> +  * Honeywell HIH-6130 / HIH-6131
> +    Prefix: 'hih6130'
> +    Addresses scanned: none
> +    Datasheet: Publicly available at the Honeywell website
> +    http://sensing.honeywell.com/index.php?ci_id=3106&la_id=1&defId=44872
> +
> +Author:
> +  Iain Paton <ipaton0 at gmail.com>
> +
> +Description
> +-----------
> +
> +The HIH-6130 & HIH-6131 are humidity and temperature sensors in a SO8 package.
> +The difference between the two devices is the HIH-6131 has a condensation

	"is that the" the instead of "is the" ?

> +filter
	Add '.'

> +
> +The devices communicate with the I2C protocol. All sensors are set to the same
> +I2C address 0x27 by default, so an entry with I2C_BOARD_INFO("hih6130", 0x27)
> +can be used in the board setup code.
> +

You could add something like

Please see Documentation/i2c/instantiating-devices for details on how to
instantiate I2C devices.

> +sysfs-Interface
> +---------------
> +
> +temp1_input - temperature input
> +humidity1_input - humidity input
> +
> +Notes
> +-----
> +
> +Command mode and alarms are not currently supported.
> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
> index 6f1d167..033c8c6 100644
> --- a/drivers/hwmon/Kconfig
> +++ b/drivers/hwmon/Kconfig
> @@ -433,6 +433,16 @@ config SENSORS_GPIO_FAN
>  	  This driver can also be built as a module.  If so, the module
>  	  will be called gpio-fan.
>  
> +config SENSORS_HIH6130
> +	tristate "Honeywell Humidicon HIH-6130 humidity/temperature sensor"
> +	depends on I2C && EXPERIMENTAL
> +	help
> +	  If you say yes here you get support for Honeywell Humidicon
> +	  HIH-6130 or HIH-6131 Humidicon humidity sensors.
> +

s/or/and/

> +	  This driver can also be built as a module.  If so, the module
> +	  will be called hih6130.
> +
>  config SENSORS_CORETEMP
>  	tristate "Intel Core/Core2/Atom temperature sensor"
>  	depends on X86 && PCI && EXPERIMENTAL
> diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
> index e1eeac1..5c4e2e9 100644
> --- a/drivers/hwmon/Makefile
> +++ b/drivers/hwmon/Makefile
> @@ -58,6 +58,7 @@ obj-$(CONFIG_SENSORS_G760A)	+= g760a.o
>  obj-$(CONFIG_SENSORS_GL518SM)	+= gl518sm.o
>  obj-$(CONFIG_SENSORS_GL520SM)	+= gl520sm.o
>  obj-$(CONFIG_SENSORS_GPIO_FAN)	+= gpio-fan.o
> +obj-$(CONFIG_SENSORS_HIH6130)	+= hih6130.o
>  obj-$(CONFIG_SENSORS_ULTRA45)	+= ultra45_env.o
>  obj-$(CONFIG_SENSORS_I5K_AMB)	+= i5k_amb.o
>  obj-$(CONFIG_SENSORS_IBMAEM)	+= ibmaem.o
> diff --git a/drivers/hwmon/hih6130.c b/drivers/hwmon/hih6130.c
> new file mode 100644
> index 0000000..d238868
> --- /dev/null
> +++ b/drivers/hwmon/hih6130.c
> @@ -0,0 +1,285 @@
> +/* Honeywell HIH-6130/HIH-6131 humidity and temperature sensor driver
> + *
> + * Copyright (C) 2012 Iain Paton <ipaton0 at gmail.com>
> + *
> + * heavily based on the sht21 driver
> + * Copyright (C) 2010 Urs Fleisch <urs.fleisch at sensirion.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA
> + *
> + * Data sheets available (2012-06-22) at
> + * http://sensing.honeywell.com/index.php?ci_id=3106&la_id=1&defId=44872
> + */
> +
> +#include <linux/module.h>
> +#include <linux/init.h>
> +#include <linux/slab.h>
> +#include <linux/i2c.h>
> +#include <linux/hwmon.h>
> +#include <linux/hwmon-sysfs.h>
> +#include <linux/err.h>
> +#include <linux/mutex.h>
> +#include <linux/device.h>
> +#include <linux/delay.h>
> +
> +/**
> + * struct hih6130 - HIH-6136 device specific data

s/6136/6130

> + * @hwmon_dev: device registered with hwmon
> + * @lock: mutex to protect measurement values
> + * @valid: only 0 before first measurement is taken

s/0/false

> + * @last_update: time of last update (jiffies)
> + * @temperature: cached temperature measurement value
> + * @humidity: cached humidity measurement value
> + */
> +struct hih6130 {
> +	struct device *hwmon_dev;
> +	struct mutex lock;
> +	bool valid;
> +	unsigned long last_update;
> +	int temperature;
> +	int humidity;
> +};
> +
> +/**
> + * hih6130_temp_ticks_to_millicelsius() - convert raw temperature ticks to
> + * milli celsius
> + * @ticks: temperature ticks value received from sensor
> + */
> +static inline int hih6130_temp_ticks_to_millicelsius(int ticks)
> +{
> +
> +	ticks = ticks >> 2;
> +	/*
> +	 * from data sheet section 5.0
> +	 * Formula T = ( ticks / ( 2^14 - 2 ) ) * 165 -40
> +	 */
> +	return (DIV_ROUND_CLOSEST((ticks * 1650), 16382) - 400) * 100;

	(ticks * 1650) -> ticks * 1650

> +}
> +
> +/**
> + * hih6130_rh_ticks_to_per_cent_mille() - convert raw humidity ticks to
> + * one-thousandths of a percent relative humidity
> + * @ticks: humidity ticks value received from sensor
> + */
> +static inline int hih6130_rh_ticks_to_per_cent_mille(int ticks)
> +{
> +
> +	ticks &= ~0xC000; /* clear status bits */
> +	/*
> +	 * from data sheet section 4.0
> +	 * Formula RH = ( ticks / ( 2^14 -2 ) ) * 100
> +	 */
> +	return DIV_ROUND_CLOSEST((ticks * 1000), 16382) * 100;

	(ticks * 1000) -> ticks * 1000

> +}
> +
> +/**
> + * hih6130_update_measurements() - get updated measurements from device
> + * @client: I2C client device
> + *
> + * Returns 0 on success, else negative errno.
> + */
> +static int hih6130_update_measurements(struct i2c_client *client)
> +{
> +	int ret = 0;
> +	int t;
> +	struct hih6130 *hih6130 = i2c_get_clientdata(client);
> +	unsigned char tmp[4];
> +	struct i2c_msg msgs[1] = {
> +		{
> +			.addr = client->addr,
> +			.flags = I2C_M_RD,
> +			.len = 4,
> +			.buf = tmp,
> +		}
> +	};
> +
> +	mutex_lock(&hih6130->lock);
> +
> +	/*
> +	 * Response time for the sensor is measured in seconds, so we have

in seconds ?

> +	 * nothing to gain from reading any faster
> +	 */
> +	if (time_after(jiffies, hih6130->last_update + HZ) || !hih6130->valid) {
> +
> +		/* write to slave address, no data, to request a measurement */
> +		ret = i2c_master_send(client, tmp, 0);
> +		if (ret < 0)
> +			goto out;
> +
> +		/* measurement cycle time is ~36.65msec */
> +		msleep(40);
> +
> +		ret = i2c_transfer(client->adapter, msgs, 1);
> +		if (ret < 0)
> +			goto out;
> +
> +		if ((tmp[0] & 0xC0) != 0) {
> +			dev_err(&client->dev, "Error while reading measurement result\n");
> +			ret = -EIO;
> +			goto out;
> +		}
> +
> +		t = (tmp[0] << 8) + tmp[1];
> +		hih6130->humidity = hih6130_rh_ticks_to_per_cent_mille(t);
> +
> +		t = (tmp[2] << 8) + tmp[3];
> +		hih6130->temperature = hih6130_temp_ticks_to_millicelsius(t);
> +
> +		hih6130->last_update = jiffies;
> +		hih6130->valid = 1;

	s/1/true/

> +	}
> +out:
> +	mutex_unlock(&hih6130->lock);
> +
> +	return ret >= 0 ? 0 : ret;
> +}
> +
> +/**
> + * hih6130_show_temperature() - show temperature measurement value in sysfs
> + * @dev: device
> + * @attr: device attribute
> + * @buf: sysfs buffer (PAGE_SIZE) where measurement values are written to
> + *
> + * Will be called on read access to temp1_input sysfs attribute.
> + * Returns number of bytes written into buffer, negative errno on error.
> + */
> +static ssize_t hih6130_show_temperature(struct device *dev,
> +					struct device_attribute *attr, char *buf)
> +{
> +	struct i2c_client *client = to_i2c_client(dev);
> +	struct hih6130 *hih6130 = i2c_get_clientdata(client);
> +	int ret = hih6130_update_measurements(client);
> +	if (ret < 0)
> +		return ret;
> +	return sprintf(buf, "%d\n", hih6130->temperature);
> +}
> +
> +/**
> + * hih6130_show_humidity() - show humidity measurement value in sysfs
> + * @dev: device
> + * @attr: device attribute
> + * @buf: sysfs buffer (PAGE_SIZE) where measurement values are written to
> + *
> + * Will be called on read access to humidity1_input sysfs attribute.
> + * Returns number of bytes written into buffer, negative errno on error.
> + */
> +static ssize_t hih6130_show_humidity(struct device *dev,
> +				     struct device_attribute *attr, char *buf)
> +{
> +	struct i2c_client *client = to_i2c_client(dev);
> +	struct hih6130 *hih6130 = i2c_get_clientdata(client);
> +	int ret = hih6130_update_measurements(client);
> +	if (ret < 0)
> +		return ret;
> +	return sprintf(buf, "%d\n", hih6130->humidity);
> +}
> +
> +/* sysfs attributes */
> +static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, hih6130_show_temperature,
> +	NULL, 0);
> +static SENSOR_DEVICE_ATTR(humidity1_input, S_IRUGO, hih6130_show_humidity,
> +	NULL, 0);
> +
> +static struct attribute *hih6130_attributes[] = {
> +	&sensor_dev_attr_temp1_input.dev_attr.attr,
> +	&sensor_dev_attr_humidity1_input.dev_attr.attr,
> +	NULL
> +};
> +
> +static const struct attribute_group hih6130_attr_group = {
> +	.attrs = hih6130_attributes,
> +};
> +
> +/**
> + * hih6130_probe() - probe device
> + * @client: I2C client device
> + * @id: device ID
> + *
> + * Called by the I2C core when an entry in the ID table matches a
> + * device's name.
> + * Returns 0 on success.
> + */
> +static int __devinit hih6130_probe(struct i2c_client *client,
> +	const struct i2c_device_id *id)

Please use similar alignments.

> +{
> +	struct hih6130 *hih6130;
> +	int err;
> +
> +	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
> +		dev_err(&client->dev, "adapter does not support true I2C\n");
> +		return -ENODEV;
> +	}
> +
> +	hih6130 = devm_kzalloc(&client->dev, sizeof(*hih6130), GFP_KERNEL);
> +	if (!hih6130)
> +		return -ENOMEM;
> +
> +	i2c_set_clientdata(client, hih6130);
> +
> +	mutex_init(&hih6130->lock);
> +
> +	err = sysfs_create_group(&client->dev.kobj, &hih6130_attr_group);
> +	if (err) {
> +		dev_dbg(&client->dev, "could not create sysfs files\n");
> +		return err;
> +	}
> +
> +	hih6130->hwmon_dev = hwmon_device_register(&client->dev);
> +	if (IS_ERR(hih6130->hwmon_dev)) {
> +		dev_dbg(&client->dev, "unable to register hwmon device\n");
> +		err = PTR_ERR(hih6130->hwmon_dev);
> +		goto fail_remove_sysfs;
> +	}
> +
> +	return 0;
> +
> +fail_remove_sysfs:
> +	sysfs_remove_group(&client->dev.kobj, &hih6130_attr_group);
> +	return err;
> +}
> +
> +/**
> + * hih6130_remove() - remove device
> + * @client: I2C client device
> + */
> +static int __devexit hih6130_remove(struct i2c_client *client)
> +{
> +	struct hih6130 *hih6130 = i2c_get_clientdata(client);
> +
> +	hwmon_device_unregister(hih6130->hwmon_dev);
> +	sysfs_remove_group(&client->dev.kobj, &hih6130_attr_group);
> +
> +	return 0;
> +}
> +
> +/* Device ID table */
> +static const struct i2c_device_id hih6130_id[] = {
> +	{ "hih6130", 0 },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(i2c, hih6130_id);
> +
> +static struct i2c_driver hih6130_driver = {
> +	.driver.name = "hih6130",
> +	.probe       = hih6130_probe,
> +	.remove      = __devexit_p(hih6130_remove),
> +	.id_table    = hih6130_id,
> +};
> +
> +module_i2c_driver(hih6130_driver);
> +
> +MODULE_AUTHOR("Iain Paton <ipaton0 at gmail.com>");
> +MODULE_DESCRIPTION("Honeywell HIH-6130 humidity and temperature sensor driver");
> +MODULE_LICENSE("GPL");
> 




More information about the lm-sensors mailing list