From mboxrd@z Thu Jan 1 00:00:00 1970 From: Guenter Roeck Date: Thu, 29 Aug 2013 09:40:52 +0000 Subject: Re: [lm-sensors] =?iso-8859-1?q?RE=A0=3A_=5BPATCH=5D_hwmon=3A__=28htu?= Message-Id: <20130829094052.GA19239@roeck-us.net> List-Id: References: <20130828161804.GB5278@roeck-us.net> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable To: "Markezana, William" Cc: khali@linux-fr.org, lm-sensors@lm-sensors.org, linux-kernel@vger.kernel.org On Thu, Aug 29, 2013 at 10:06:00AM +0200, Markezana, William wrote: Please see Documentation/SubmittingPatches, section 15, "The canonical patch format". Also, please run your patch through scripts/checkpatch.pl; we won't accept it with checkpatch warnings or errors unless you provide a good reas= on why the problem should be acceptable. It is also customary to include a list of changes made compared to the previous version, as explained in section 15 of SubmittingPatches. Thanks, Guenter > diff --git a/Documentation/hwmon/htu21 b/Documentation/hwmon/htu21 > new file mode 100644 > index 0000000..ddcef55 > --- /dev/null > +++ b/Documentation/hwmon/htu21 > @@ -0,0 +1,46 @@ > +Kernel driver htu21 > +=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D > + > +Supported chips: > + * Measurement Specialties HTU21D > + Prefix: 'htu21' > + Addresses scanned: none > + Datasheet: Publicly available at the Measurement Specialties website > + http://www.meas-spec.com/downloads/HTU21D.pdf > + > + > +Author: > + William Markezana > + > +Description > +----------- > + > +The HTU21D is a humidity and temperature sensor in a DFN package of > +only 3 x 3 mm footprint and 0.9 mm height. > + > +The devices communicate with the I2C protocol. All sensors are set to th= e same > +I2C address 0x40, so an entry with I2C_BOARD_INFO("htu21", 0x40) can be = used > +in the board setup code. > + > +This driver does not auto-detect devices. You will have to instantiate t= he=20 > +devices explicitly. Please see Documentation/i2c/instantiating-devices=20 > +for details." > + > +sysfs-Interface > +--------------- > + > +temp1_input - temperature input > +humidity1_input - humidity input > + > +Notes > +----- > + > +The driver uses the default resolution settings of 12 bit for humidity a= nd 14 > +bit for temperature, which results in typical measurement times of 11 ms= for > +humidity and 44 ms for temperature. To keep self heating below 0.1 degree > +Celsius, the device should not be active for more than 10% of the time. = For=20 > +this reason, the driver performs no more than two measurements per secon= d and=20 > +reports cached information if polled more frequently. > + > +Different resolutions, the on-chip heater, using the CRC checksum and re= ading > +the serial number are not supported yet. > diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig > index e989f7f..eb46eb8 100644 > --- a/drivers/hwmon/Kconfig > +++ b/drivers/hwmon/Kconfig > @@ -511,6 +511,16 @@ config SENSORS_HIH6130 > This driver can also be built as a module. If so, the module > will be called hih6130. > =20 > +config SENSORS_HTU21 > + tristate "Measurement Specialties HTU21D humidity and temperature senso= rs" > + depends on I2C > + help > + If you say yes here you get support for the Measurement Specialties > + HTU21D humidity and temperature sensors. > + > + This driver can also be built as a module. If so, the module > + will be called htu21. > + > config SENSORS_CORETEMP > tristate "Intel Core/Core2/Atom temperature sensor" > depends on X86 > diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile > index 4f0fb52..ec7cde0 100644 > --- a/drivers/hwmon/Makefile > +++ b/drivers/hwmon/Makefile > @@ -65,6 +65,7 @@ obj-$(CONFIG_SENSORS_GL518SM) +=3D gl518sm.o > obj-$(CONFIG_SENSORS_GL520SM) +=3D gl520sm.o > obj-$(CONFIG_SENSORS_GPIO_FAN) +=3D gpio-fan.o > obj-$(CONFIG_SENSORS_HIH6130) +=3D hih6130.o > +obj-$(CONFIG_SENSORS_HTU21) +=3D htu21.o > obj-$(CONFIG_SENSORS_ULTRA45) +=3D ultra45_env.o > obj-$(CONFIG_SENSORS_I5K_AMB) +=3D i5k_amb.o > obj-$(CONFIG_SENSORS_IBMAEM) +=3D ibmaem.o > diff --git a/drivers/hwmon/htu21.c b/drivers/hwmon/htu21.c > new file mode 100644 > index 0000000..d9470fb > --- /dev/null > +++ b/drivers/hwmon/htu21.c > @@ -0,0 +1,198 @@ > +/* > + * Measurement Specialties HTU21D humidity and temperature sensor driver > + * > + * Copyright (C) 2013 William Markezana > + * > + * 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. > + * > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +/* HTU21 Commands */ > +#define HTU21_T_MEASUREMENT_HM 0xE3 > +#define HTU21_RH_MEASUREMENT_HM 0xE5 > + > +struct htu21 { > + struct device *hwmon_dev; > + struct mutex lock; > + bool valid; > + unsigned long last_update; > + int temperature; > + int humidity; > +}; > + > +static inline int htu21_temp_ticks_to_millicelsius(int ticks) > +{ > + ticks &=3D ~0x0003; /* clear status bits */ > + /* > + * Formula T =3D -46.85 + 175.72 * ST / 2^16 from datasheet p14, > + * optimized for integer fixed point (3 digits) arithmetic > + */ > + return ((21965 * ticks) >> 13) - 46850; > +} > + > +static inline int htu21_rh_ticks_to_per_cent_mille(int ticks) > +{ > + ticks &=3D ~0x0003; /* clear status bits */ > + /* > + * Formula RH =3D -6 + 125 * SRH / 2^16 from datasheet p14, > + * optimized for integer fixed point (3 digits) arithmetic > + */ > + return ((15625 * ticks) >> 13) - 6000; > +} > + > +static int htu21_update_measurements(struct i2c_client *client) > +{ > + int ret =3D 0; > + struct htu21 *htu21 =3D i2c_get_clientdata(client); > + > + mutex_lock(&htu21->lock); > + > + if (time_after(jiffies, htu21->last_update + HZ / 2) || !htu21->valid) { > + ret =3D i2c_smbus_read_word_swapped(client, HTU21_T_MEASUREMENT_HM); > + if (ret < 0) > + goto out; > + htu21->temperature =3D htu21_temp_ticks_to_millicelsius(ret); > + ret =3D i2c_smbus_read_word_swapped(client, HTU21_RH_MEASUREMENT_HM); > + if (ret < 0) > + goto out; > + htu21->humidity =3D htu21_rh_ticks_to_per_cent_mille(ret); > + htu21->last_update =3D jiffies; > + htu21->valid =3D true; > + } > +out: > + mutex_unlock(&htu21->lock); > + > + return ret >=3D 0 ? 0 : ret; > +} > + > +static ssize_t htu21_show_temperature(struct device *dev, > + struct device_attribute *attr, > + char *buf) > +{ > + struct i2c_client *client =3D to_i2c_client(dev); > + struct htu21 *htu21 =3D i2c_get_clientdata(client); > + int ret =3D htu21_update_measurements(client); > + if (ret < 0) > + return ret; > + return sprintf(buf, "%d\n", htu21->temperature); > +} > + > +static ssize_t htu21_show_humidity(struct device *dev, > + struct device_attribute *attr, > + char *buf) > +{ > + struct i2c_client *client =3D to_i2c_client(dev); > + struct htu21 *htu21 =3D i2c_get_clientdata(client); > + int ret =3D htu21_update_measurements(client); > + if (ret < 0) > + return ret; > + return sprintf(buf, "%d\n", htu21->humidity); > +} > + > +static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO,=20 > + htu21_show_temperature, NULL, 0); > +static SENSOR_DEVICE_ATTR(humidity1_input, S_IRUGO,=20 > + htu21_show_humidity, NULL, 0); > + > +static struct attribute *htu21_attributes[] =3D { > + &sensor_dev_attr_temp1_input.dev_attr.attr, > + &sensor_dev_attr_humidity1_input.dev_attr.attr, > + NULL > +}; > + > +static const struct attribute_group htu21_group =3D { > + .attrs =3D htu21_attributes, > +}; > + > +static int htu21_probe(struct i2c_client *client, > + const struct i2c_device_id *id) > +{ > + struct htu21 *htu21; > + int err; > + > + if (!i2c_check_functionality(client->adapter, > + I2C_FUNC_SMBUS_READ_WORD_DATA)) { > + dev_err(&client->dev, > + "adapter does not support SMBus word transactions\n"); > + return -ENODEV; > + } > + > + htu21 =3D devm_kzalloc(&client->dev, sizeof(*htu21), GFP_KERNEL); > + if (!htu21) > + return -ENOMEM; > + > + i2c_set_clientdata(client, htu21); > + > + mutex_init(&htu21->lock); > + > + err =3D sysfs_create_group(&client->dev.kobj, &htu21_group); > + if (err) { > + dev_dbg(&client->dev, "could not create sysfs files\n"); > + return err; > + } > + htu21->hwmon_dev =3D hwmon_device_register(&client->dev); > + if (IS_ERR(htu21->hwmon_dev)) { > + dev_dbg(&client->dev, "unable to register hwmon device\n"); > + err =3D PTR_ERR(htu21->hwmon_dev); > + goto error; > + } > + > + dev_info(&client->dev, "initialized\n"); > + > + return 0; > + > +error: > + sysfs_remove_group(&client->dev.kobj, &htu21_group); > + return err; > +} > + > +static int htu21_remove(struct i2c_client *client) > +{ > + struct htu21 *htu21 =3D i2c_get_clientdata(client); > + > + hwmon_device_unregister(htu21->hwmon_dev); > + sysfs_remove_group(&client->dev.kobj, &htu21_group); > + > + return 0; > +} > + > +static const struct i2c_device_id htu21_id[] =3D { > + { "htu21", 0 }, > + { } > +}; > +MODULE_DEVICE_TABLE(i2c, htu21_id); > + > +static struct i2c_driver htu21_driver =3D { > + .class =3D I2C_CLASS_HWMON, > + .driver =3D { > + .name =3D "htu21", > + }, > + .probe =3D htu21_probe, > + .remove =3D htu21_remove, > + .id_table =3D htu21_id, > +}; > + > +module_i2c_driver(htu21_driver); > + > +MODULE_AUTHOR("William Markezana "); > +MODULE_DESCRIPTION("MEAS HTU21D humidity and temperature sensor driver"); > +MODULE_LICENSE("GPL"); >=20 >=20 >=20 > -------- Message d'origine-------- > De: Guenter Roeck de la part de Guenter Roeck > Date: mer. 28/08/2013 18:18 > =C0: Markezana, William > Cc: khali@linux-fr.org; lm-sensors@lm-sensors.org; linux-kernel@vger.kern= el.org > Objet : Re: [PATCH] hwmon: (htu21) Add Measurement Specialties HTU21D sup= port > =20 > On Wed, Aug 28, 2013 at 08:49:36AM +0200, Markezana, William wrote: > > From 55fc390d0079841405d5345b55a6e158ca5f3749 Mon Sep 17 00:00:00 2001 > > From: William Markezana > > Date: Wed, 28 Aug 2013 08:33:49 +0200 > > Subject: [PATCH] hwmon: (htu21) Add Measurement Specialties HTU21D supp= ort > >=20 >=20 > Your patch got corrupted and produces lots of checkpatch errors as result > (and can not be aplied). YOu might want to use a diffeent mailer for the = next > version. >=20 > In addition to that, there are several other checkpatch errors and warnin= gs. >=20 > ERROR: trailing statements should be on next line > WARNING: line over 80 characters > ERROR: Missing Signed-off-by: line(s) >=20 > Some more comments below. >=20 > Thanks, > Guenter >=20 > > --- > > Documentation/hwmon/htu21 | 43 ++++++++++ > > drivers/hwmon/Kconfig | 10 +++ > > drivers/hwmon/Makefile | 1 + > > drivers/hwmon/htu21.c | 201 +++++++++++++++++++++++++++++++++++++= ++++++++ > > 4 files changed, 255 insertions(+) > > create mode 100644 Documentation/hwmon/htu21 > > create mode 100644 drivers/hwmon/htu21.c > >=20 > > diff --git a/Documentation/hwmon/htu21 b/Documentation/hwmon/htu21 > > new file mode 100644 > > index 0000000..ab756bc > > --- /dev/null > > +++ b/Documentation/hwmon/htu21 > > @@ -0,0 +1,43 @@ > > +Kernel driver htu21 > > +=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D > > + > > +Supported chips: > > + * Measurement Specialties HTU21D > > + Prefix: 'htu21' > > + Addresses scanned: none > > + Datasheet: Publicly available at the Measurement Specialties websi= te > > + http://www.meas-spec.com/downloads/HTU21D.pdf > > + > > + > > +Author: > > + William Markezana > > + > > +Description > > +----------- > > + > > +HTU21D(F), the new digital humidity sensor with temperature output of = MEAS is about=20 > > +to set new standards in terms of size and intelligence: Embedded in a = reflow=20 > > +solderable Dual Flat No leads (DFN) package of 3 x 3 mm foot print and= 0.9 mm height=20 > > +it provides calibrated, linearized signals in digital, I=B2C format. > > + > Please drop the marketing pitch. Just describe what the chip is doing. >=20 > > +The devices communicate with the I2C protocol. All sensors are set to = the same > > +I2C address 0x40, so an entry with I2C_BOARD_INFO("htu21", 0x40) can b= e used > > +in the board setup code. > > + >=20 > I would suggest to add something like >=20 > "This driver does not auto-detect devices. You will have to instantiate t= he > devices explicitly. Please see Documentation/i2c/instantiating-devices for > details." >=20 > to the notes instead. After all, there are other means to instantiate the > driver. >=20 > > +sysfs-Interface > > +--------------- > > + > > +temp1_input - temperature input > > +humidity1_input - humidity input > > + > > +Notes > > +----- > > + > > +The driver uses the default resolution settings of 12 bit for humidity= and 14 > > +bit for temperature, which results in typical measurement times of 11 = ms for > > +humidity and 44 ms for temperature. To keep self heating below 0.1 deg= ree > > +Celsius, the device should not be active for more than 10% of the time, > > +e.g. maximum two measurements per second at the given resolution. > > + > You might want to add that the driver is doing this, or phrase it differe= ntly, > such as >=20 > "To keep self heating below 0.1 degree Celsius, the device should not be > active for more than 10% of the time. For this reason, the driver perform= s no > more than two measurements per second and reports cached information if p= olled > more frequently." >=20 > > +Different resolutions, the on-chip heater, using the CRC checksum and = reading > > +the serial number are not supported yet. > > diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig > > index e989f7f..eb46eb8 100644 > > --- a/drivers/hwmon/Kconfig > > +++ b/drivers/hwmon/Kconfig > > @@ -511,6 +511,16 @@ config SENSORS_HIH6130 > > This driver can also be built as a module. If so, the module > > will be called hih6130. > > =20 > > +config SENSORS_HTU21 > > + tristate "Measurement Specialties HTU21D humidity and temperature sen= sors" > > + depends on I2C > > + help > > + If you say yes here you get support for the Measurement Specialties > > + HTU21D humidity and temperature sensors. > > + > > + This driver can also be built as a module. If so, the module > > + will be called htu21. > > + > > config SENSORS_CORETEMP > > tristate "Intel Core/Core2/Atom temperature sensor" > > depends on X86 > > diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile > > index 4f0fb52..ec7cde0 100644 > > --- a/drivers/hwmon/Makefile > > +++ b/drivers/hwmon/Makefile > > @@ -65,6 +65,7 @@ obj-$(CONFIG_SENSORS_GL518SM) +=3D gl518sm.o > > obj-$(CONFIG_SENSORS_GL520SM) +=3D gl520sm.o > > obj-$(CONFIG_SENSORS_GPIO_FAN) +=3D gpio-fan.o > > obj-$(CONFIG_SENSORS_HIH6130) +=3D hih6130.o > > +obj-$(CONFIG_SENSORS_HTU21) +=3D htu21.o > > obj-$(CONFIG_SENSORS_ULTRA45) +=3D ultra45_env.o > > obj-$(CONFIG_SENSORS_I5K_AMB) +=3D i5k_amb.o > > obj-$(CONFIG_SENSORS_IBMAEM) +=3D ibmaem.o > > diff --git a/drivers/hwmon/htu21.c b/drivers/hwmon/htu21.c > > new file mode 100644 > > index 0000000..8b8d132 > > --- /dev/null > > +++ b/drivers/hwmon/htu21.c > > @@ -0,0 +1,201 @@ > > +/* Measurement Specialties HTU21D humidity and temperature sensor driv= er > > + * > > + * Copyright (C) 2013 William Markezana > > + * > > + * 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., 675 Mass Ave, Cambridge, MA 02139, USA. > > + * >=20 > Please drop the "You should have..." note and the FSF address. The license > is in the "COPYING" file, and the address may change. >=20 > > + * Data sheet available (7/2013) at > > + * http://www.meas-spec.com/downloads/HTU21D.pdf >=20 > The datasheet location is already mentioned in the Documentation. Please = drop > it from here, so we don't have to update it at two places is the link cha= nges. >=20 > > + */ > > + > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > + > > +/* HTU21 Commands */ > > +#define HTU21_T_MEASUREMENT_HM 0xE3 > > +#define HTU21_RH_MEASUREMENT_HM 0xE5 > > + > Please use tabs before the 0x >=20 > > +struct htu21 { > > + struct device *hwmon_dev; > > + struct mutex lock; > > + char valid; >=20 > The above should be bool (and use '=3D true' for assignments). >=20 > > + unsigned long last_update; > > + int temperature; > > + int humidity; > > +}; > > + > > +static inline int htu21_temp_ticks_to_millicelsius(int ticks) > > +{ > > + ticks &=3D ~0x0003; /* clear status bits */ > > + /* > > + * Formula T =3D -46.85 + 175.72 * ST / 2^16 from datasheet p14, > > + * optimized for integer fixed point (3 digits) arithmetic > > + */ > > + return ((21965 * ticks) >> 13) - 46850; > > +} > > + > > +static inline int htu21_rh_ticks_to_per_cent_mille(int ticks) > > +{ > > + ticks &=3D ~0x0003; /* clear status bits */ > > + /* > > + * Formula RH =3D -6 + 125 * SRH / 2^16 from datasheet p14, > > + * optimized for integer fixed point (3 digits) arithmetic > > + */ > > + return ((15625 * ticks) >> 13) - 6000; > > +} > > + > > +static int htu21_update_measurements(struct i2c_client *client) > > +{ > > + int ret =3D 0; > > + struct htu21 *htu21 =3D i2c_get_clientdata(client); > > + > > + mutex_lock(&htu21->lock); > > + > > + if (time_after(jiffies, htu21->last_update + HZ / 2) || !htu21->valid= ) { > > + ret =3D i2c_smbus_read_word_swapped(client, HTU21_T_MEASUREMENT_HM); > > + if (ret < 0) > > + goto out; > > + htu21->temperature =3D htu21_temp_ticks_to_millicelsius(ret); > > + ret =3D i2c_smbus_read_word_swapped(client, HTU21_RH_MEASUREMENT_HM); > > + if (ret < 0) > > + goto out; > > + htu21->humidity =3D htu21_rh_ticks_to_per_cent_mille(ret); > > + htu21->last_update =3D jiffies; > > + htu21->valid =3D 1; > > + } > > +out: > > + mutex_unlock(&htu21->lock); > > + > > + return ret >=3D 0 ? 0 : ret; > > +} > > + > > +static ssize_t htu21_show_temperature(struct device *dev, > > + struct device_attribute *attr, > > + char *buf) > > +{ > > + struct i2c_client *client =3D to_i2c_client(dev); > > + struct htu21 *htu21 =3D i2c_get_clientdata(client); > > + int ret =3D htu21_update_measurements(client); > > + if (ret < 0) > > + return ret; > > + return sprintf(buf, "%d\n", htu21->temperature); > > +} > > + > > +static ssize_t htu21_show_humidity(struct device *dev, > > + struct device_attribute *attr, > > + char *buf) > > +{ > > + struct i2c_client *client =3D to_i2c_client(dev); > > + struct htu21 *htu21 =3D i2c_get_clientdata(client); > > + int ret =3D htu21_update_measurements(client); > > + if (ret < 0) > > + return ret; > > + return sprintf(buf, "%d\n", htu21->humidity); > > +} > > + > > +static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, htu21_show_temperature= , NULL, 0); >=20 > space instead of tab before the NULL >=20 > > +static SENSOR_DEVICE_ATTR(humidity1_input, S_IRUGO, htu21_show_humidit= y, NULL, 0); > > + > > +static struct attribute *htu21_attributes[] =3D { > > + &sensor_dev_attr_temp1_input.dev_attr.attr, > > + &sensor_dev_attr_humidity1_input.dev_attr.attr, > > + NULL > > +}; > > + > > +static const struct attribute_group htu21_group =3D { > > + .attrs =3D htu21_attributes, > > +}; > > + > > +static int htu21_probe(struct i2c_client *client, > > + const struct i2c_device_id *id) > > +{ > > + struct htu21 *htu21; > > + int err; > > + > > + if (!i2c_check_functionality(client->adapter, > > + I2C_FUNC_SMBUS_WORD_DATA)) { >=20 > Strictly speaking, you only need I2C_FUNC_SMBUS_READ_WORD_DATA. >=20 > > + dev_err(&client->dev, > > + "adapter does not support SMBus word transactions\n"); > > + return -ENODEV; > > + } > > + > > + htu21 =3D devm_kzalloc(&client->dev, sizeof(*htu21), GFP_KERNEL); > > + if (!htu21) > > + return -ENOMEM; > > + > > + i2c_set_clientdata(client, htu21); > > + > > + mutex_init(&htu21->lock); > > + > > + err =3D sysfs_create_group(&client->dev.kobj, &htu21_group); > > + if (err) { > > + dev_dbg(&client->dev, "could not create sysfs files\n"); > > + return err; > > + } > > + htu21->hwmon_dev =3D hwmon_device_register(&client->dev); > > + if (IS_ERR(htu21->hwmon_dev)) { > > + dev_dbg(&client->dev, "unable to register hwmon device\n"); > > + err =3D PTR_ERR(htu21->hwmon_dev); > > + goto error; > > + } > > + > > + dev_info(&client->dev, "initialized\n"); > > + > > + return 0; > > + > > +error: > > + sysfs_remove_group(&client->dev.kobj, &htu21_group); > > + return err; > > +} > > + > > +static int htu21_remove(struct i2c_client *client) > > +{ > > + struct htu21 *htu21 =3D i2c_get_clientdata(client); > > + > > + hwmon_device_unregister(htu21->hwmon_dev); > > + sysfs_remove_group(&client->dev.kobj, &htu21_group); > > + > > + return 0; > > +} > > + > > +static const struct i2c_device_id htu21_id[] =3D { > > + { "htu21", 0 }, > > + { } > > +}; > > +MODULE_DEVICE_TABLE(i2c, htu21_id); > > + > > +static struct i2c_driver htu21_driver =3D { > > + .class =3D I2C_CLASS_HWMON, > > + .driver =3D { > > + .name =3D "htu21", > > + }, > > + .probe =3D htu21_probe, > > + .remove =3D htu21_remove, > > + .id_table =3D htu21_id, > > +}; > > + > > +module_i2c_driver(htu21_driver); > > + > > +MODULE_AUTHOR("William Markezana "); > > +MODULE_DESCRIPTION("Measurement Specialties HTU21D humidity and temper= ature sensor driver"); > > +MODULE_LICENSE("GPL"); > > --=20 > > 1.7.10.4 > >=20 > >=20 >=20 _______________________________________________ lm-sensors mailing list lm-sensors@lm-sensors.org http://lists.lm-sensors.org/mailman/listinfo/lm-sensors From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755878Ab3H2Jk6 (ORCPT ); Thu, 29 Aug 2013 05:40:58 -0400 Received: from mail-pd0-f173.google.com ([209.85.192.173]:63027 "EHLO mail-pd0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751650Ab3H2Jk4 (ORCPT ); Thu, 29 Aug 2013 05:40:56 -0400 Date: Thu, 29 Aug 2013 02:40:52 -0700 From: Guenter Roeck To: "Markezana, William" Cc: khali@linux-fr.org, lm-sensors@lm-sensors.org, linux-kernel@vger.kernel.org Subject: Re: =?iso-8859-1?B?UkWgOiBbUEFUQ0hdIGh3?= =?iso-8859-1?Q?mon=3A?= (htu21) Add Measurement Specialties HTU21D support Message-ID: <20130829094052.GA19239@roeck-us.net> References: <20130828161804.GB5278@roeck-us.net> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Aug 29, 2013 at 10:06:00AM +0200, Markezana, William wrote: Please see Documentation/SubmittingPatches, section 15, "The canonical patch format". Also, please run your patch through scripts/checkpatch.pl; we won't accept it with checkpatch warnings or errors unless you provide a good reason why the problem should be acceptable. It is also customary to include a list of changes made compared to the previous version, as explained in section 15 of SubmittingPatches. Thanks, Guenter > diff --git a/Documentation/hwmon/htu21 b/Documentation/hwmon/htu21 > new file mode 100644 > index 0000000..ddcef55 > --- /dev/null > +++ b/Documentation/hwmon/htu21 > @@ -0,0 +1,46 @@ > +Kernel driver htu21 > +=================== > + > +Supported chips: > + * Measurement Specialties HTU21D > + Prefix: 'htu21' > + Addresses scanned: none > + Datasheet: Publicly available at the Measurement Specialties website > + http://www.meas-spec.com/downloads/HTU21D.pdf > + > + > +Author: > + William Markezana > + > +Description > +----------- > + > +The HTU21D is a humidity and temperature sensor in a DFN package of > +only 3 x 3 mm footprint and 0.9 mm height. > + > +The devices communicate with the I2C protocol. All sensors are set to the same > +I2C address 0x40, so an entry with I2C_BOARD_INFO("htu21", 0x40) can be used > +in the board setup code. > + > +This driver does not auto-detect devices. You will have to instantiate the > +devices explicitly. Please see Documentation/i2c/instantiating-devices > +for details." > + > +sysfs-Interface > +--------------- > + > +temp1_input - temperature input > +humidity1_input - humidity input > + > +Notes > +----- > + > +The driver uses the default resolution settings of 12 bit for humidity and 14 > +bit for temperature, which results in typical measurement times of 11 ms for > +humidity and 44 ms for temperature. To keep self heating below 0.1 degree > +Celsius, the device should not be active for more than 10% of the time. For > +this reason, the driver performs no more than two measurements per second and > +reports cached information if polled more frequently. > + > +Different resolutions, the on-chip heater, using the CRC checksum and reading > +the serial number are not supported yet. > diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig > index e989f7f..eb46eb8 100644 > --- a/drivers/hwmon/Kconfig > +++ b/drivers/hwmon/Kconfig > @@ -511,6 +511,16 @@ config SENSORS_HIH6130 > This driver can also be built as a module. If so, the module > will be called hih6130. > > +config SENSORS_HTU21 > + tristate "Measurement Specialties HTU21D humidity and temperature sensors" > + depends on I2C > + help > + If you say yes here you get support for the Measurement Specialties > + HTU21D humidity and temperature sensors. > + > + This driver can also be built as a module. If so, the module > + will be called htu21. > + > config SENSORS_CORETEMP > tristate "Intel Core/Core2/Atom temperature sensor" > depends on X86 > diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile > index 4f0fb52..ec7cde0 100644 > --- a/drivers/hwmon/Makefile > +++ b/drivers/hwmon/Makefile > @@ -65,6 +65,7 @@ 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-$(CONFIG_SENSORS_HTU21) += htu21.o > obj-$(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/htu21.c b/drivers/hwmon/htu21.c > new file mode 100644 > index 0000000..d9470fb > --- /dev/null > +++ b/drivers/hwmon/htu21.c > @@ -0,0 +1,198 @@ > +/* > + * Measurement Specialties HTU21D humidity and temperature sensor driver > + * > + * Copyright (C) 2013 William Markezana > + * > + * 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. > + * > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +/* HTU21 Commands */ > +#define HTU21_T_MEASUREMENT_HM 0xE3 > +#define HTU21_RH_MEASUREMENT_HM 0xE5 > + > +struct htu21 { > + struct device *hwmon_dev; > + struct mutex lock; > + bool valid; > + unsigned long last_update; > + int temperature; > + int humidity; > +}; > + > +static inline int htu21_temp_ticks_to_millicelsius(int ticks) > +{ > + ticks &= ~0x0003; /* clear status bits */ > + /* > + * Formula T = -46.85 + 175.72 * ST / 2^16 from datasheet p14, > + * optimized for integer fixed point (3 digits) arithmetic > + */ > + return ((21965 * ticks) >> 13) - 46850; > +} > + > +static inline int htu21_rh_ticks_to_per_cent_mille(int ticks) > +{ > + ticks &= ~0x0003; /* clear status bits */ > + /* > + * Formula RH = -6 + 125 * SRH / 2^16 from datasheet p14, > + * optimized for integer fixed point (3 digits) arithmetic > + */ > + return ((15625 * ticks) >> 13) - 6000; > +} > + > +static int htu21_update_measurements(struct i2c_client *client) > +{ > + int ret = 0; > + struct htu21 *htu21 = i2c_get_clientdata(client); > + > + mutex_lock(&htu21->lock); > + > + if (time_after(jiffies, htu21->last_update + HZ / 2) || !htu21->valid) { > + ret = i2c_smbus_read_word_swapped(client, HTU21_T_MEASUREMENT_HM); > + if (ret < 0) > + goto out; > + htu21->temperature = htu21_temp_ticks_to_millicelsius(ret); > + ret = i2c_smbus_read_word_swapped(client, HTU21_RH_MEASUREMENT_HM); > + if (ret < 0) > + goto out; > + htu21->humidity = htu21_rh_ticks_to_per_cent_mille(ret); > + htu21->last_update = jiffies; > + htu21->valid = true; > + } > +out: > + mutex_unlock(&htu21->lock); > + > + return ret >= 0 ? 0 : ret; > +} > + > +static ssize_t htu21_show_temperature(struct device *dev, > + struct device_attribute *attr, > + char *buf) > +{ > + struct i2c_client *client = to_i2c_client(dev); > + struct htu21 *htu21 = i2c_get_clientdata(client); > + int ret = htu21_update_measurements(client); > + if (ret < 0) > + return ret; > + return sprintf(buf, "%d\n", htu21->temperature); > +} > + > +static ssize_t htu21_show_humidity(struct device *dev, > + struct device_attribute *attr, > + char *buf) > +{ > + struct i2c_client *client = to_i2c_client(dev); > + struct htu21 *htu21 = i2c_get_clientdata(client); > + int ret = htu21_update_measurements(client); > + if (ret < 0) > + return ret; > + return sprintf(buf, "%d\n", htu21->humidity); > +} > + > +static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, > + htu21_show_temperature, NULL, 0); > +static SENSOR_DEVICE_ATTR(humidity1_input, S_IRUGO, > + htu21_show_humidity, NULL, 0); > + > +static struct attribute *htu21_attributes[] = { > + &sensor_dev_attr_temp1_input.dev_attr.attr, > + &sensor_dev_attr_humidity1_input.dev_attr.attr, > + NULL > +}; > + > +static const struct attribute_group htu21_group = { > + .attrs = htu21_attributes, > +}; > + > +static int htu21_probe(struct i2c_client *client, > + const struct i2c_device_id *id) > +{ > + struct htu21 *htu21; > + int err; > + > + if (!i2c_check_functionality(client->adapter, > + I2C_FUNC_SMBUS_READ_WORD_DATA)) { > + dev_err(&client->dev, > + "adapter does not support SMBus word transactions\n"); > + return -ENODEV; > + } > + > + htu21 = devm_kzalloc(&client->dev, sizeof(*htu21), GFP_KERNEL); > + if (!htu21) > + return -ENOMEM; > + > + i2c_set_clientdata(client, htu21); > + > + mutex_init(&htu21->lock); > + > + err = sysfs_create_group(&client->dev.kobj, &htu21_group); > + if (err) { > + dev_dbg(&client->dev, "could not create sysfs files\n"); > + return err; > + } > + htu21->hwmon_dev = hwmon_device_register(&client->dev); > + if (IS_ERR(htu21->hwmon_dev)) { > + dev_dbg(&client->dev, "unable to register hwmon device\n"); > + err = PTR_ERR(htu21->hwmon_dev); > + goto error; > + } > + > + dev_info(&client->dev, "initialized\n"); > + > + return 0; > + > +error: > + sysfs_remove_group(&client->dev.kobj, &htu21_group); > + return err; > +} > + > +static int htu21_remove(struct i2c_client *client) > +{ > + struct htu21 *htu21 = i2c_get_clientdata(client); > + > + hwmon_device_unregister(htu21->hwmon_dev); > + sysfs_remove_group(&client->dev.kobj, &htu21_group); > + > + return 0; > +} > + > +static const struct i2c_device_id htu21_id[] = { > + { "htu21", 0 }, > + { } > +}; > +MODULE_DEVICE_TABLE(i2c, htu21_id); > + > +static struct i2c_driver htu21_driver = { > + .class = I2C_CLASS_HWMON, > + .driver = { > + .name = "htu21", > + }, > + .probe = htu21_probe, > + .remove = htu21_remove, > + .id_table = htu21_id, > +}; > + > +module_i2c_driver(htu21_driver); > + > +MODULE_AUTHOR("William Markezana "); > +MODULE_DESCRIPTION("MEAS HTU21D humidity and temperature sensor driver"); > +MODULE_LICENSE("GPL"); > > > > -------- Message d'origine-------- > De: Guenter Roeck de la part de Guenter Roeck > Date: mer. 28/08/2013 18:18 > À: Markezana, William > Cc: khali@linux-fr.org; lm-sensors@lm-sensors.org; linux-kernel@vger.kernel.org > Objet : Re: [PATCH] hwmon: (htu21) Add Measurement Specialties HTU21D support > > On Wed, Aug 28, 2013 at 08:49:36AM +0200, Markezana, William wrote: > > From 55fc390d0079841405d5345b55a6e158ca5f3749 Mon Sep 17 00:00:00 2001 > > From: William Markezana > > Date: Wed, 28 Aug 2013 08:33:49 +0200 > > Subject: [PATCH] hwmon: (htu21) Add Measurement Specialties HTU21D support > > > > Your patch got corrupted and produces lots of checkpatch errors as result > (and can not be aplied). YOu might want to use a diffeent mailer for the next > version. > > In addition to that, there are several other checkpatch errors and warnings. > > ERROR: trailing statements should be on next line > WARNING: line over 80 characters > ERROR: Missing Signed-off-by: line(s) > > Some more comments below. > > Thanks, > Guenter > > > --- > > Documentation/hwmon/htu21 | 43 ++++++++++ > > drivers/hwmon/Kconfig | 10 +++ > > drivers/hwmon/Makefile | 1 + > > drivers/hwmon/htu21.c | 201 +++++++++++++++++++++++++++++++++++++++++++++ > > 4 files changed, 255 insertions(+) > > create mode 100644 Documentation/hwmon/htu21 > > create mode 100644 drivers/hwmon/htu21.c > > > > diff --git a/Documentation/hwmon/htu21 b/Documentation/hwmon/htu21 > > new file mode 100644 > > index 0000000..ab756bc > > --- /dev/null > > +++ b/Documentation/hwmon/htu21 > > @@ -0,0 +1,43 @@ > > +Kernel driver htu21 > > +=================== > > + > > +Supported chips: > > + * Measurement Specialties HTU21D > > + Prefix: 'htu21' > > + Addresses scanned: none > > + Datasheet: Publicly available at the Measurement Specialties website > > + http://www.meas-spec.com/downloads/HTU21D.pdf > > + > > + > > +Author: > > + William Markezana > > + > > +Description > > +----------- > > + > > +HTU21D(F), the new digital humidity sensor with temperature output of MEAS is about > > +to set new standards in terms of size and intelligence: Embedded in a reflow > > +solderable Dual Flat No leads (DFN) package of 3 x 3 mm foot print and 0.9 mm height > > +it provides calibrated, linearized signals in digital, I²C format. > > + > Please drop the marketing pitch. Just describe what the chip is doing. > > > +The devices communicate with the I2C protocol. All sensors are set to the same > > +I2C address 0x40, so an entry with I2C_BOARD_INFO("htu21", 0x40) can be used > > +in the board setup code. > > + > > I would suggest to add something like > > "This driver does not auto-detect devices. You will have to instantiate the > devices explicitly. Please see Documentation/i2c/instantiating-devices for > details." > > to the notes instead. After all, there are other means to instantiate the > driver. > > > +sysfs-Interface > > +--------------- > > + > > +temp1_input - temperature input > > +humidity1_input - humidity input > > + > > +Notes > > +----- > > + > > +The driver uses the default resolution settings of 12 bit for humidity and 14 > > +bit for temperature, which results in typical measurement times of 11 ms for > > +humidity and 44 ms for temperature. To keep self heating below 0.1 degree > > +Celsius, the device should not be active for more than 10% of the time, > > +e.g. maximum two measurements per second at the given resolution. > > + > You might want to add that the driver is doing this, or phrase it differently, > such as > > "To keep self heating below 0.1 degree Celsius, the device should not be > active for more than 10% of the time. For this reason, the driver performs no > more than two measurements per second and reports cached information if polled > more frequently." > > > +Different resolutions, the on-chip heater, using the CRC checksum and reading > > +the serial number are not supported yet. > > diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig > > index e989f7f..eb46eb8 100644 > > --- a/drivers/hwmon/Kconfig > > +++ b/drivers/hwmon/Kconfig > > @@ -511,6 +511,16 @@ config SENSORS_HIH6130 > > This driver can also be built as a module. If so, the module > > will be called hih6130. > > > > +config SENSORS_HTU21 > > + tristate "Measurement Specialties HTU21D humidity and temperature sensors" > > + depends on I2C > > + help > > + If you say yes here you get support for the Measurement Specialties > > + HTU21D humidity and temperature sensors. > > + > > + This driver can also be built as a module. If so, the module > > + will be called htu21. > > + > > config SENSORS_CORETEMP > > tristate "Intel Core/Core2/Atom temperature sensor" > > depends on X86 > > diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile > > index 4f0fb52..ec7cde0 100644 > > --- a/drivers/hwmon/Makefile > > +++ b/drivers/hwmon/Makefile > > @@ -65,6 +65,7 @@ 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-$(CONFIG_SENSORS_HTU21) += htu21.o > > obj-$(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/htu21.c b/drivers/hwmon/htu21.c > > new file mode 100644 > > index 0000000..8b8d132 > > --- /dev/null > > +++ b/drivers/hwmon/htu21.c > > @@ -0,0 +1,201 @@ > > +/* Measurement Specialties HTU21D humidity and temperature sensor driver > > + * > > + * Copyright (C) 2013 William Markezana > > + * > > + * 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., 675 Mass Ave, Cambridge, MA 02139, USA. > > + * > > Please drop the "You should have..." note and the FSF address. The license > is in the "COPYING" file, and the address may change. > > > + * Data sheet available (7/2013) at > > + * http://www.meas-spec.com/downloads/HTU21D.pdf > > The datasheet location is already mentioned in the Documentation. Please drop > it from here, so we don't have to update it at two places is the link changes. > > > + */ > > + > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > + > > +/* HTU21 Commands */ > > +#define HTU21_T_MEASUREMENT_HM 0xE3 > > +#define HTU21_RH_MEASUREMENT_HM 0xE5 > > + > Please use tabs before the 0x > > > +struct htu21 { > > + struct device *hwmon_dev; > > + struct mutex lock; > > + char valid; > > The above should be bool (and use '= true' for assignments). > > > + unsigned long last_update; > > + int temperature; > > + int humidity; > > +}; > > + > > +static inline int htu21_temp_ticks_to_millicelsius(int ticks) > > +{ > > + ticks &= ~0x0003; /* clear status bits */ > > + /* > > + * Formula T = -46.85 + 175.72 * ST / 2^16 from datasheet p14, > > + * optimized for integer fixed point (3 digits) arithmetic > > + */ > > + return ((21965 * ticks) >> 13) - 46850; > > +} > > + > > +static inline int htu21_rh_ticks_to_per_cent_mille(int ticks) > > +{ > > + ticks &= ~0x0003; /* clear status bits */ > > + /* > > + * Formula RH = -6 + 125 * SRH / 2^16 from datasheet p14, > > + * optimized for integer fixed point (3 digits) arithmetic > > + */ > > + return ((15625 * ticks) >> 13) - 6000; > > +} > > + > > +static int htu21_update_measurements(struct i2c_client *client) > > +{ > > + int ret = 0; > > + struct htu21 *htu21 = i2c_get_clientdata(client); > > + > > + mutex_lock(&htu21->lock); > > + > > + if (time_after(jiffies, htu21->last_update + HZ / 2) || !htu21->valid) { > > + ret = i2c_smbus_read_word_swapped(client, HTU21_T_MEASUREMENT_HM); > > + if (ret < 0) > > + goto out; > > + htu21->temperature = htu21_temp_ticks_to_millicelsius(ret); > > + ret = i2c_smbus_read_word_swapped(client, HTU21_RH_MEASUREMENT_HM); > > + if (ret < 0) > > + goto out; > > + htu21->humidity = htu21_rh_ticks_to_per_cent_mille(ret); > > + htu21->last_update = jiffies; > > + htu21->valid = 1; > > + } > > +out: > > + mutex_unlock(&htu21->lock); > > + > > + return ret >= 0 ? 0 : ret; > > +} > > + > > +static ssize_t htu21_show_temperature(struct device *dev, > > + struct device_attribute *attr, > > + char *buf) > > +{ > > + struct i2c_client *client = to_i2c_client(dev); > > + struct htu21 *htu21 = i2c_get_clientdata(client); > > + int ret = htu21_update_measurements(client); > > + if (ret < 0) > > + return ret; > > + return sprintf(buf, "%d\n", htu21->temperature); > > +} > > + > > +static ssize_t htu21_show_humidity(struct device *dev, > > + struct device_attribute *attr, > > + char *buf) > > +{ > > + struct i2c_client *client = to_i2c_client(dev); > > + struct htu21 *htu21 = i2c_get_clientdata(client); > > + int ret = htu21_update_measurements(client); > > + if (ret < 0) > > + return ret; > > + return sprintf(buf, "%d\n", htu21->humidity); > > +} > > + > > +static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, htu21_show_temperature, NULL, 0); > > space instead of tab before the NULL > > > +static SENSOR_DEVICE_ATTR(humidity1_input, S_IRUGO, htu21_show_humidity, NULL, 0); > > + > > +static struct attribute *htu21_attributes[] = { > > + &sensor_dev_attr_temp1_input.dev_attr.attr, > > + &sensor_dev_attr_humidity1_input.dev_attr.attr, > > + NULL > > +}; > > + > > +static const struct attribute_group htu21_group = { > > + .attrs = htu21_attributes, > > +}; > > + > > +static int htu21_probe(struct i2c_client *client, > > + const struct i2c_device_id *id) > > +{ > > + struct htu21 *htu21; > > + int err; > > + > > + if (!i2c_check_functionality(client->adapter, > > + I2C_FUNC_SMBUS_WORD_DATA)) { > > Strictly speaking, you only need I2C_FUNC_SMBUS_READ_WORD_DATA. > > > + dev_err(&client->dev, > > + "adapter does not support SMBus word transactions\n"); > > + return -ENODEV; > > + } > > + > > + htu21 = devm_kzalloc(&client->dev, sizeof(*htu21), GFP_KERNEL); > > + if (!htu21) > > + return -ENOMEM; > > + > > + i2c_set_clientdata(client, htu21); > > + > > + mutex_init(&htu21->lock); > > + > > + err = sysfs_create_group(&client->dev.kobj, &htu21_group); > > + if (err) { > > + dev_dbg(&client->dev, "could not create sysfs files\n"); > > + return err; > > + } > > + htu21->hwmon_dev = hwmon_device_register(&client->dev); > > + if (IS_ERR(htu21->hwmon_dev)) { > > + dev_dbg(&client->dev, "unable to register hwmon device\n"); > > + err = PTR_ERR(htu21->hwmon_dev); > > + goto error; > > + } > > + > > + dev_info(&client->dev, "initialized\n"); > > + > > + return 0; > > + > > +error: > > + sysfs_remove_group(&client->dev.kobj, &htu21_group); > > + return err; > > +} > > + > > +static int htu21_remove(struct i2c_client *client) > > +{ > > + struct htu21 *htu21 = i2c_get_clientdata(client); > > + > > + hwmon_device_unregister(htu21->hwmon_dev); > > + sysfs_remove_group(&client->dev.kobj, &htu21_group); > > + > > + return 0; > > +} > > + > > +static const struct i2c_device_id htu21_id[] = { > > + { "htu21", 0 }, > > + { } > > +}; > > +MODULE_DEVICE_TABLE(i2c, htu21_id); > > + > > +static struct i2c_driver htu21_driver = { > > + .class = I2C_CLASS_HWMON, > > + .driver = { > > + .name = "htu21", > > + }, > > + .probe = htu21_probe, > > + .remove = htu21_remove, > > + .id_table = htu21_id, > > +}; > > + > > +module_i2c_driver(htu21_driver); > > + > > +MODULE_AUTHOR("William Markezana "); > > +MODULE_DESCRIPTION("Measurement Specialties HTU21D humidity and temperature sensor driver"); > > +MODULE_LICENSE("GPL"); > > -- > > 1.7.10.4 > > > > >