Merge tag 'hwmon-for-linus-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging

Pull hwmon updates from Guenter Roeck:

- New drivers for FTS BMC "Teutates", TI INA3221, and Sensirion SHT3x.

- Added support for Microchip MCP9808 and TI TMP461.

- Cleanup and minor fixes in various drivers.

* tag 'hwmon-for-linus-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging: (37 commits)
Documentation: dtb: xgene: Add hwmon dts binding documentation
hwmon: (ftsteutates) Remove unused including <linux/version.h>
hwmon: (adt7411) set bit 3 in CFG1 register
hwmon: Add driver for FTS BMC chip "Teutates"
hwmon: (sht3x) add humidity heater element control
hwmon: (jc42) Add support for generic JC-42.4 devicetree binding
dt/bindings: Add bindings for JC-42.4 compatible temperature sensors
hwmon: (tmp102) Convert to use regmap, and drop local cache
hwmon: (tmp102) Rework chip configuration
hwmon: (tmp102) Improve handling of initial read delay
hwmon: (lm90) Drop unnecessary else statements
hwmon: (lm90) Use bool for valid flag
hwmon: (lm90) Read limit registers only once
hwmon: (lm90) Simplify read functions
hwmon: (lm90) Use devm_hwmon_device_register_with_groups
hwmon: (lm90) Use devm_add_action for cleanup
hwmon: (lm75) Convert to use regmap
hwmon: (lm75) Add update_interval attribute
hwmon: (lm75) Drop lm75_read_value and lm75_write_value
hwmon: (lm75) Handle cleanup with devm_add_action
...

Documentation/devicetree/bindings/hwmon/apm-xgene-hwmon.txt

···
+APM X-Gene hwmon driver
+
+APM X-Gene SOC sensors are accessed over the "SLIMpro" mailbox.
+
+Required properties :
+ - compatible : should be "apm,xgene-slimpro-hwmon"
+ - mboxes : use the label reference for the mailbox as the first parameter.
+	    The second parameter is the channel number.
+
+Example :
+	hwmonslimpro {
+		compatible = "apm,xgene-slimpro-hwmon";
+		mboxes = <&mailbox 7>;
+	};

Documentation/devicetree/bindings/hwmon/jc42.txt

···
+Properties for Jedec JC-42.4 compatible temperature sensors
+
+Required properties:
+- compatible: May include a device-specific string consisting of the
+	      manufacturer and the name of the chip. A list of supported
+	      chip names follows.
+	      Must include "jedec,jc-42.4-temp" for any Jedec JC-42.4
+	      compatible temperature sensor.
+
+	      Supported chip names:
+		adi,adt7408
+		atmel,at30ts00
+		atmel,at30tse004
+		onnn,cat6095
+		onnn,cat34ts02
+		maxim,max6604
+		microchip,mcp9804
+		microchip,mcp9805
+		microchip,mcp9808
+		microchip,mcp98243
+		microchip,mcp98244
+		microchip,mcp9843
+		nxp,se97
+		nxp,se98
+		st,stts2002
+		st,stts2004
+		st,stts3000
+		st,stts424
+		st,stts424e
+		idt,tse2002
+		idt,tse2004
+		idt,ts3000
+		idt,ts3001
+
+- reg: I2C address
+
+Example:
+
+temp-sensor@1a {
+	compatible = "jedec,jc-42.4-temp";
+	reg = <0x1a>;
+};

Documentation/hwmon/abituguru

···
 				 AW9D-MAX) (2)
 	1) For revisions 2 and 3 uGuru's the driver can autodetect the
 	   sensortype (Volt or Temp) for bank1 sensors, for revision 1 uGuru's
-	   this doesnot always work. For these uGuru's the autodection can
+	   this does not always work. For these uGuru's the autodetection can
 	   be overridden with the bank1_types module param. For all 3 known
 	   revison 1 motherboards the correct use of this param is:
 	   bank1_types=1,1,0,0,0,0,0,2,0,0,0,0,2,0,0,1

Documentation/hwmon/ftsteutates

···
+Kernel driver ftsteutates
+=====================
+
+Supported chips:
+  * FTS Teutates
+    Prefix: 'ftsteutates'
+    Addresses scanned: I2C 0x73 (7-Bit)
+
+Author: Thilo Cestonaro <[e-mail]>
+
+
+Description
+-----------
+The BMC Teutates is the Eleventh generation of Superior System
+monitoring and thermal management solution. It is builds on the basic
+functionality of the BMC Theseus and contains several new features and
+enhancements. It can monitor up to 4 voltages, 16 temperatures and
+8 fans. It also contains an integrated watchdog which is currently
+implemented in this driver.
+
+Specification of the chip can be found here:
+ftp:///pub/Mainboard-OEM-Sales/Services/Software&Tools/Linux_SystemMonitoring&Watchdog&GPIO/BMC-Teutates_Specification_V1.21.pdf
+ftp:///pub/Mainboard-OEM-Sales/Services/Software&Tools/Linux_SystemMonitoring&Watchdog&GPIO/Fujitsu_mainboards-1-Sensors_HowTo-en-US.pdf

Documentation/hwmon/ina3221

···
+Kernel driver ina3221
+=====================
+
+Supported chips:
+  * Texas Instruments INA3221
+    Prefix: 'ina3221'
+    Addresses: I2C 0x40 - 0x43
+    Datasheet: Publicly available at the Texas Instruments website
+               http://www.ti.com/
+
+Author: Andrew F. Davis <[e-mail]>
+
+Description
+-----------
+
+The Texas Instruments INA3221 monitors voltage, current, and power on the high
+side of up to three D.C. power supplies. The INA3221 monitors both shunt drop
+and supply voltage, with programmable conversion times and averaging, current
+and power are calculated host-side from these.
+
+Sysfs entries
+-------------
+
+in[123]_input           Bus voltage(mV) channels
+curr[123]_input         Current(mA) measurement channels
+shunt[123]_resistor     Shunt resistance(uOhm) channels
+curr[123]_crit          Critical alert current(mA) setting, activates the
+                          corresponding alarm when the respective current
+                          is above this value
+curr[123]_crit_alarm    Critical alert current limit exceeded
+curr[123]_max           Warning alert current(mA) setting, activates the
+                          corresponding alarm when the respective current
+                          average is above this value.
+curr[123]_max_alarm     Warning alert current limit exceeded
+in[456]_input           Shunt voltage(uV) for channels 1, 2, and 3 respectively

Documentation/hwmon/jc42

···
   * Maxim MAX6604
     Datasheets:
 	http://datasheets.maxim-ic.com/en/ds/MAX6604.pdf
-  * Microchip MCP9804, MCP9805, MCP98242, MCP98243, MCP98244, MCP9843
+  * Microchip MCP9804, MCP9805, MCP9808, MCP98242, MCP98243, MCP98244, MCP9843
     Datasheets:
 	http://ww1.microchip.com/downloads/en/DeviceDoc/22203C.pdf
 	http://ww1.microchip.com/downloads/en/DeviceDoc/21977b.pdf
+	http://ww1.microchip.com/downloads/en/DeviceDoc/25095A.pdf
 	http://ww1.microchip.com/downloads/en/DeviceDoc/21996a.pdf
 	http://ww1.microchip.com/downloads/en/DeviceDoc/22153c.pdf
 	http://ww1.microchip.com/downloads/en/DeviceDoc/22327A.pdf

Documentation/hwmon/max1668

···
 chips.
 
 The three devices are very similar, but the MAX1805 has a reduced feature
-set; only two remote temperature inputs vs the four avaible on the other
+set; only two remote temperature inputs vs the four available on the other
 two ICs.
 
 The driver is able to distinguish between the devices and creates sysfs

Documentation/hwmon/sht3x

···
+Kernel driver sht3x
+===================
+
+Supported chips:
+  * Sensirion SHT3x-DIS
+    Prefix: 'sht3x'
+    Addresses scanned: none
+    Datasheet: http://www.sensirion.com/fileadmin/user_upload/customers/sensirion/Dokumente/Humidity/Sensirion_Humidity_Datasheet_SHT3x_DIS.pdf
+
+Author:
+  David Frey <[e-mail]>
+  Pascal Sachs <[e-mail]>
+
+Description
+-----------
+
+This driver implements support for the Sensirion SHT3x-DIS chip, a humidity
+and temperature sensor. Temperature is measured in degrees celsius, relative
+humidity is expressed as a percentage. In the sysfs interface, all values are
+scaled by 1000, i.e. the value for 31.5 degrees celsius is 31500.
+
+The device communicates with the I2C protocol. Sensors can have the I2C
+addresses 0x44 or 0x45, depending on the wiring. See
+Documentation/i2c/instantiating-devices for methods to instantiate the device.
+
+There are two options configurable by means of sht3x_platform_data:
+1. blocking (pull the I2C clock line down while performing the measurement) or
+   non-blocking mode. Blocking mode will guarantee the fastest result but
+   the I2C bus will be busy during that time. By default, non-blocking mode
+   is used. Make sure clock-stretching works properly on your device if you
+   want to use blocking mode.
+2. high or low accuracy. High accuracy is used by default and using it is
+   strongly recommended.
+
+The sht3x sensor supports a single shot mode as well as 5 periodic measure
+modes, which can be controlled with the update_interval sysfs interface.
+The allowed update_interval in milliseconds are as follows:
+  *     0   single shot mode
+  *  2000   0.5 Hz periodic measurement
+  *  1000   1   Hz periodic measurement
+  *   500   2   Hz periodic measurement
+  *   250   4   Hz periodic measurement
+  *   100  10   Hz periodic measurement
+
+In the periodic measure mode, the sensor automatically triggers a measurement
+with the configured update interval on the chip. When a temperature or humidity
+reading exceeds the configured limits, the alert attribute is set to 1 and
+the alert pin on the sensor is set to high.
+When the temperature and humidity readings move back between the hysteresis
+values, the alert bit is set to 0 and the alert pin on the sensor is set to
+low.
+
+sysfs-Interface
+---------------
+
+temp1_input:        temperature input
+humidity1_input:    humidity input
+temp1_max:          temperature max value
+temp1_max_hyst:     temperature hysteresis value for max limit
+humidity1_max:      humidity max value
+humidity1_max_hyst: humidity hysteresis value for max limit
+temp1_min:          temperature min value
+temp1_min_hyst:     temperature hysteresis value for min limit
+humidity1_min:      humidity min value
+humidity1_min_hyst: humidity hysteresis value for min limit
+temp1_alarm:        alarm flag is set to 1 if the temperature is outside the
+                    configured limits. Alarm only works in periodic measure mode
+humidity1_alarm:    alarm flag is set to 1 if the humidity is outside the
+                    configured limits. Alarm only works in periodic measure mode
+heater_enable:      heater enable, heating element removes excess humidity from
+                    sensor
+                        0: turned off
+                        1: turned on
+update_interval:    update interval, 0 for single shot, interval in msec
+                    for periodic measurement. If the interval is not supported
+                    by the sensor, the next faster interval is chosen

Documentation/hwmon/submitting-patches

···
     Documentation/SubmittingPatches
     Documentation/CodingStyle
 
-* If your patch generates checkpatch warnings, please refrain from explanations
-  such as "I don't like that coding style". Keep in mind that each unnecessary
-  warning helps hiding a real problem. If you don't like the kernel coding
-  style, don't write kernel drivers.
+* Please run your patch through 'checkpatch --strict'. There should be no
+  errors, no warnings, and few if any check messages. If there are any
+  messages, please be prepared to explain.
+
+* If your patch generates checkpatch errors, warnings, or check messages,
+  please refrain from explanations such as "I prefer that coding style".
+  Keep in mind that each unnecessary message helps hiding a real problem,
+  and a consistent coding style makes it easier for others to understand
+  and review the code.
 
 * Please test your patch thoroughly. We are not your test group.
   Sometimes a patch can not or not completely be tested because of missing
···
 
 * Make sure that all dependencies are listed in Kconfig.
 
+* Please list include files in alphabetic order.
+
+* Please align continuation lines with '(' on the previous line.
+
 * Avoid forward declarations if you can. Rearrange the code if necessary.
+
+* Avoid macros to generate groups of sensor attributes. It not only confuses
+  checkpatch, but also makes it more difficult to review the code.
 
 * Avoid calculations in macros and macro-generated functions. While such macros
   may save a line or so in the source, it obfuscates the code and makes code
   review more difficult. It may also result in code which is more complicated
   than necessary. Use inline functions or just regular functions instead.
 
+* Limit the number of kernel log messages. In general, your driver should not
+  generate an error message just because a runtime operation failed. Report
+  errors to user space instead, using an appropriate error code. Keep in mind
+  that kernel error log messages not only fill up the kernel log, but also are
+  printed synchronously, most likely with interrupt disabled, often to a serial
+  console. Excessive logging can seriously affect system performance.
+
 * Use devres functions whenever possible to allocate resources. For rationale
   and supported functions, please see Documentation/driver-model/devres.txt.
+  If a function is not supported by devres, consider using devm_add_action().
 
 * If the driver has a detect function, make sure it is silent. Debug messages
   and messages printed after a successful detection are acceptable, but it
···
   writing to it might cause a bad misconfiguration.
 
 * Make sure there are no race conditions in the probe function. Specifically,
-  completely initialize your chip first, then create sysfs entries and register
-  with the hwmon subsystem.
+  completely initialize your chip and your driver first, then register with
+  the hwmon subsystem.
+
+* Use devm_hwmon_device_register_with_groups() or, if your driver needs a remove
+  function, hwmon_device_register_with_groups() to register your driver with the
+  hwmon subsystem. Try using devm_add_action() instead of a remove function if
+  possible. Do not use hwmon_device_register().
+
+* Your driver should be buildable as module. If not, please be prepared to
+  explain why it has to be built into the kernel.
 
 * Do not provide support for deprecated sysfs attributes.
 

Documentation/hwmon/tmp401

···
     Prefix: 'tmp435'
     Addresses scanned: I2C 0x48 - 0x4f
     Datasheet: http://focus.ti.com/docs/prod/folders/print/tmp435.html
+  * Texas Instruments TMP461
+    Prefix: 'tmp461'
+    Datasheet: http://www.ti.com/product/tmp461
 
 Authors:
          Hans de Goede <[e-mail]>
···
 -----------
 
 This driver implements support for Texas Instruments TMP401, TMP411,
-TMP431, TMP432 and TMP435 chips. These chips implement one or two remote
-and one local temperature sensors. Temperature is measured in degrees
+TMP431, TMP432, TMP435, and TMP461 chips. These chips implement one or two
+remote and one local temperature sensors. Temperature is measured in degrees
 Celsius. Resolution of the remote sensor is 0.0625 degree. Local
 sensor resolution can be set to 0.5, 0.25, 0.125 or 0.0625 degree (not
 supported by the driver so far, so using the default resolution of 0.5
···
 
 TMP432 is compatible with TMP401 and TMP431. It supports two external
 temperature sensors.
+
+TMP461 is compatible with TMP401. It supports offset correction
+that is applied to the remote sensor.
+
+* Sensor offset values are temperature values
+
+  Exported via sysfs attribute tempX_offset

drivers/hwmon/Kconfig

···
 	  This driver can also be built as a module.  If so, the module
 	  will be called fschmd.
 
+config SENSORS_FTSTEUTATES
+	tristate "Fujitsu Technology Solutions sensor chip Teutates"
+	depends on I2C && WATCHDOG
+	select WATCHDOG_CORE
+	help
+	  If you say yes here you get support for the Fujitsu Technology
+	  Solutions (FTS) sensor chip "Teutates" including support for
+	  the integrated watchdog.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called ftsteutates.
+
 config SENSORS_GL518SM
 	tristate "Genesys Logic GL518SM"
 	depends on I2C
···
 	  temperature sensors, which are used on many DDR3 memory modules for
 	  mobile devices and servers.  Support will include, but not be limited
 	  to, ADT7408, AT30TS00, CAT34TS02, CAT6095, MAX6604, MCP9804, MCP9805,
-	  MCP98242, MCP98243, MCP98244, MCP9843, SE97, SE98, STTS424(E),
-	  STTS2002, STTS3000, TSE2002, TSE2004, TS3000, and TS3001.
+	  MCP9808, MCP98242, MCP98243, MCP98244, MCP9843, SE97, SE98,
+	  STTS424(E), STTS2002, STTS3000, TSE2002, TSE2004, TS3000, and TS3001.
 
 	  This driver can also be built as a module.  If so, the module
 	  will be called jc42.
···
 	tristate "National Semiconductor LM75 and compatibles"
 	depends on I2C
 	depends on THERMAL || !THERMAL_OF
+	select REGMAP_I2C
 	help
 	  If you say yes here you get support for one common type of
 	  temperature sensor chip, with models including:
···
 	  This driver can also be built as a module.  If so, the module
 	  will be called sht21.
 
+config SENSORS_SHT3x
+	tristate "Sensiron humidity and temperature sensors. SHT3x and compat."
+	depends on I2C
+	select CRC8
+	help
+	  If you say yes here you get support for the Sensiron SHT30 and SHT31
+	  humidity and temperature sensors.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called sht3x.
+
 config SENSORS_SHTC1
 	tristate "Sensiron humidity and temperature sensors. SHTC1 and compat."
 	depends on I2C
···
 	  This driver can also be built as a module.  If so, the module
 	  will be called ina2xx.
 
+config SENSORS_INA3221
+	tristate "Texas Instruments INA3221 Triple Power Monitor"
+	depends on I2C
+	select REGMAP_I2C
+	help
+	  If you say yes here you get support for  the TI INA3221 Triple Power
+	  Monitor.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called ina3221.
+
 config SENSORS_TC74
 	tristate "Microchip TC74"
 	depends on I2C
···
 	tristate "Texas Instruments TMP102"
 	depends on I2C
 	depends on THERMAL || !THERMAL_OF
+	select REGMAP_I2C
 	help
 	  If you say yes here you get support for Texas Instruments TMP102
 	  sensor chips.
···
 	depends on I2C
 	help
 	  If you say yes here you get support for Texas Instruments TMP401,
-	  TMP411, TMP431, TMP432 and TMP435 temperature sensor chips.
+	  TMP411, TMP431, TMP432, TMP435, and TMP461 temperature sensor chips.
 
 	  This driver can also be built as a module.  If so, the module
 	  will be called tmp401.

drivers/hwmon/Makefile

···
 obj-$(CONFIG_SENSORS_F75375S)	+= f75375s.o
 obj-$(CONFIG_SENSORS_FAM15H_POWER) += fam15h_power.o
 obj-$(CONFIG_SENSORS_FSCHMD)	+= fschmd.o
+obj-$(CONFIG_SENSORS_FTSTEUTATES) += ftsteutates.o
 obj-$(CONFIG_SENSORS_G760A)	+= g760a.o
 obj-$(CONFIG_SENSORS_G762)	+= g762.o
 obj-$(CONFIG_SENSORS_GL518SM)	+= gl518sm.o
···
 obj-$(CONFIG_SENSORS_IIO_HWMON) += iio_hwmon.o
 obj-$(CONFIG_SENSORS_INA209)	+= ina209.o
 obj-$(CONFIG_SENSORS_INA2XX)	+= ina2xx.o
+obj-$(CONFIG_SENSORS_INA3221)	+= ina3221.o
 obj-$(CONFIG_SENSORS_IT87)	+= it87.o
 obj-$(CONFIG_SENSORS_JC42)	+= jc42.o
 obj-$(CONFIG_SENSORS_JZ4740)	+= jz4740-hwmon.o
···
 obj-$(CONFIG_SENSORS_SCH5636)	+= sch5636.o
 obj-$(CONFIG_SENSORS_SHT15)	+= sht15.o
 obj-$(CONFIG_SENSORS_SHT21)	+= sht21.o
+obj-$(CONFIG_SENSORS_SHT3x)	+= sht3x.o
 obj-$(CONFIG_SENSORS_SHTC1)	+= shtc1.o
 obj-$(CONFIG_SENSORS_SIS5595)	+= sis5595.o
 obj-$(CONFIG_SENSORS_SMM665)	+= smm665.o

drivers/hwmon/ad7314.c

···
 
 struct ad7314_data {
 	struct spi_device	*spi_dev;
-	struct device		*hwmon_dev;
 	u16 rx ____cacheline_aligned;
 };
 
···
 	}
 }
 
-static ssize_t ad7314_show_name(struct device *dev,
-				struct device_attribute *devattr, char *buf)
-{
-	return sprintf(buf, "%s\n", to_spi_device(dev)->modalias);
-}
-
-static DEVICE_ATTR(name, S_IRUGO, ad7314_show_name, NULL);
 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO,
 			  ad7314_show_temperature, NULL, 0);
 
-static struct attribute *ad7314_attributes[] = {
-	&dev_attr_name.attr,
+static struct attribute *ad7314_attrs[] = {
 	&sensor_dev_attr_temp1_input.dev_attr.attr,
 	NULL,
 };
 
-static const struct attribute_group ad7314_group = {
-	.attrs = ad7314_attributes,
-};
+ATTRIBUTE_GROUPS(ad7314);
 
 static int ad7314_probe(struct spi_device *spi_dev)
 {
-	int ret;
 	struct ad7314_data *chip;
+	struct device *hwmon_dev;
 
 	chip = devm_kzalloc(&spi_dev->dev, sizeof(*chip), GFP_KERNEL);
 	if (chip == NULL)
 		return -ENOMEM;
 
-	spi_set_drvdata(spi_dev, chip);
-
-	ret = sysfs_create_group(&spi_dev->dev.kobj, &ad7314_group);
-	if (ret < 0)
-		return ret;
-
-	chip->hwmon_dev = hwmon_device_register(&spi_dev->dev);
-	if (IS_ERR(chip->hwmon_dev)) {
-		ret = PTR_ERR(chip->hwmon_dev);
-		goto error_remove_group;
-	}
 	chip->spi_dev = spi_dev;
-
-	return 0;
-error_remove_group:
-	sysfs_remove_group(&spi_dev->dev.kobj, &ad7314_group);
-	return ret;
-}
-
-static int ad7314_remove(struct spi_device *spi_dev)
-{
-	struct ad7314_data *chip = spi_get_drvdata(spi_dev);
-
-	hwmon_device_unregister(chip->hwmon_dev);
-	sysfs_remove_group(&spi_dev->dev.kobj, &ad7314_group);
-
-	return 0;
+	hwmon_dev = devm_hwmon_device_register_with_groups(&spi_dev->dev,
+							   spi_dev->modalias,
+							   chip, ad7314_groups);
+	return PTR_ERR_OR_ZERO(hwmon_dev);
 }
 
 static const struct spi_device_id ad7314_id[] = {
···
 		.name = "ad7314",
 	},
 	.probe = ad7314_probe,
-	.remove = ad7314_remove,
 	.id_table = ad7314_id,
 };
 

drivers/hwmon/ads7871.c

···
 #include <linux/hwmon.h>
 #include <linux/hwmon-sysfs.h>
 #include <linux/err.h>
-#include <linux/mutex.h>
 #include <linux/delay.h>
 
 #define DEVICE_NAME	"ads7871"
 
 struct ads7871_data {
-	struct device	*hwmon_dev;
-	struct mutex	update_lock;
+	struct spi_device *spi;
 };
 
 static int ads7871_read_reg8(struct spi_device *spi, int reg)
···
 static ssize_t show_voltage(struct device *dev,
 		struct device_attribute *da, char *buf)
 {
-	struct spi_device *spi = to_spi_device(dev);
+	struct ads7871_data *pdata = dev_get_drvdata(dev);
+	struct spi_device *spi = pdata->spi;
 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
 	int ret, val, i = 0;
 	uint8_t channel, mux_cnv;
···
 	}
 }
 
-static ssize_t ads7871_show_name(struct device *dev,
-				 struct device_attribute *devattr, char *buf)
-{
-	return sprintf(buf, "%s\n", to_spi_device(dev)->modalias);
-}
-
 static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, show_voltage, NULL, 0);
 static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, show_voltage, NULL, 1);
 static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, show_voltage, NULL, 2);
···
 static SENSOR_DEVICE_ATTR(in6_input, S_IRUGO, show_voltage, NULL, 6);
 static SENSOR_DEVICE_ATTR(in7_input, S_IRUGO, show_voltage, NULL, 7);
 
-static DEVICE_ATTR(name, S_IRUGO, ads7871_show_name, NULL);
-
-static struct attribute *ads7871_attributes[] = {
+static struct attribute *ads7871_attrs[] = {
 	&sensor_dev_attr_in0_input.dev_attr.attr,
 	&sensor_dev_attr_in1_input.dev_attr.attr,
 	&sensor_dev_attr_in2_input.dev_attr.attr,
···
 	&sensor_dev_attr_in5_input.dev_attr.attr,
 	&sensor_dev_attr_in6_input.dev_attr.attr,
 	&sensor_dev_attr_in7_input.dev_attr.attr,
-	&dev_attr_name.attr,
 	NULL
 };
 
-static const struct attribute_group ads7871_group = {
-	.attrs = ads7871_attributes,
-};
+ATTRIBUTE_GROUPS(ads7871);
 
 static int ads7871_probe(struct spi_device *spi)
 {
-	int ret, err;
+	struct device *dev = &spi->dev;
+	int ret;
 	uint8_t val;
 	struct ads7871_data *pdata;
-
-	dev_dbg(&spi->dev, "probe\n");
+	struct device *hwmon_dev;
 
 	/* Configure the SPI bus */
 	spi->mode = (SPI_MODE_0);
···
 	ads7871_write_reg8(spi, REG_OSC_CONTROL, val);
 	ret = ads7871_read_reg8(spi, REG_OSC_CONTROL);
 
-	dev_dbg(&spi->dev, "REG_OSC_CONTROL write:%x, read:%x\n", val, ret);
+	dev_dbg(dev, "REG_OSC_CONTROL write:%x, read:%x\n", val, ret);
 	/*
 	 * because there is no other error checking on an SPI bus
 	 * we need to make sure we really have a chip
···
 	if (val != ret)
 		return -ENODEV;
 
-	pdata = devm_kzalloc(&spi->dev, sizeof(struct ads7871_data),
-			     GFP_KERNEL);
+	pdata = devm_kzalloc(dev, sizeof(struct ads7871_data), GFP_KERNEL);
 	if (!pdata)
 		return -ENOMEM;
 
-	err = sysfs_create_group(&spi->dev.kobj, &ads7871_group);
-	if (err < 0)
-		return err;
+	pdata->spi = spi;
 
-	spi_set_drvdata(spi, pdata);
-
-	pdata->hwmon_dev = hwmon_device_register(&spi->dev);
-	if (IS_ERR(pdata->hwmon_dev)) {
-		err = PTR_ERR(pdata->hwmon_dev);
-		goto error_remove;
-	}
-
-	return 0;
-
-error_remove:
-	sysfs_remove_group(&spi->dev.kobj, &ads7871_group);
-	return err;
-}
-
-static int ads7871_remove(struct spi_device *spi)
-{
-	struct ads7871_data *pdata = spi_get_drvdata(spi);
-
-	hwmon_device_unregister(pdata->hwmon_dev);
-	sysfs_remove_group(&spi->dev.kobj, &ads7871_group);
-	return 0;
+	hwmon_dev = devm_hwmon_device_register_with_groups(dev, spi->modalias,
+							   pdata,
+							   ads7871_groups);
+	return PTR_ERR_OR_ZERO(hwmon_dev);
 }
 
 static struct spi_driver ads7871_driver = {
 	.driver = {
 		.name = DEVICE_NAME,
 	},
-
 	.probe = ads7871_probe,
-	.remove = ads7871_remove,
 };
 
 module_spi_driver(ads7871_driver);

drivers/hwmon/adt7411.c

···
 
 #define ADT7411_REG_CFG1			0x18
 #define ADT7411_CFG1_START_MONITOR		(1 << 0)
+#define ADT7411_CFG1_RESERVED_BIT3		(1 << 3)
 
 #define ADT7411_REG_CFG2			0x19
 #define ADT7411_CFG2_DISABLE_AVG		(1 << 5)
···
 	mutex_init(&data->device_lock);
 	mutex_init(&data->update_lock);
 
+	/* According to the datasheet, we must only write 1 to bit 3 */
 	ret = adt7411_modify_bit(client, ADT7411_REG_CFG1,
-				 ADT7411_CFG1_START_MONITOR, 1);
+				 ADT7411_CFG1_RESERVED_BIT3
+				 | ADT7411_CFG1_START_MONITOR, 1);
 	if (ret < 0)
 		return ret;
 

drivers/hwmon/dell-smm-hwmon.c

···
 #define I8K_HWMON_HAVE_TEMP4	(1 << 3)
 #define I8K_HWMON_HAVE_FAN1	(1 << 4)
 #define I8K_HWMON_HAVE_FAN2	(1 << 5)
+#define I8K_HWMON_HAVE_FAN3	(1 << 6)
 
 MODULE_AUTHOR("Massimo Dal Zotto ([e-mail])");
 MODULE_AUTHOR("Pali Rohár <[e-mail]>");
···
 	int rc;
 	int eax = regs->eax;
 	cpumask_var_t old_mask;
+
+#ifdef DEBUG
+	int ebx = regs->ebx;
+	unsigned long duration;
+	ktime_t calltime, delta, rettime;
+
+	calltime = ktime_get();
+#endif
 
 	/* SMM requires CPU 0 */
 	if (!alloc_cpumask_var(&old_mask, GFP_KERNEL))
···
 out:
 	set_cpus_allowed_ptr(current, old_mask);
 	free_cpumask_var(old_mask);
+
+#ifdef DEBUG
+	rettime = ktime_get();
+	delta = ktime_sub(rettime, calltime);
+	duration = ktime_to_ns(delta) >> 10;
+	pr_debug("smm(0x%.4x 0x%.4x) = 0x%.4x  (took %7lu usecs)\n", eax, ebx,
+		(rc ? 0xffff : regs->eax & 0xffff), duration);
+#endif
+
 	return rc;
 }
 
···
 static int i8k_get_fan_type(int fan)
 {
 	/* I8K_SMM_GET_FAN_TYPE SMM call is expensive, so cache values */
-	static int types[2] = { INT_MIN, INT_MIN };
+	static int types[3] = { INT_MIN, INT_MIN, INT_MIN };
 
 	if (types[fan] == INT_MIN)
 		types[fan] = _i8k_get_fan_type(fan);
···
 			  1);
 static SENSOR_DEVICE_ATTR(pwm2, S_IRUGO | S_IWUSR, i8k_hwmon_show_pwm,
 			  i8k_hwmon_set_pwm, 1);
+static SENSOR_DEVICE_ATTR(fan3_input, S_IRUGO, i8k_hwmon_show_fan, NULL,
+			  2);
+static SENSOR_DEVICE_ATTR(fan3_label, S_IRUGO, i8k_hwmon_show_fan_label, NULL,
+			  2);
+static SENSOR_DEVICE_ATTR(pwm3, S_IRUGO | S_IWUSR, i8k_hwmon_show_pwm,
+			  i8k_hwmon_set_pwm, 2);
 
 static struct attribute *i8k_attrs[] = {
 	&sensor_dev_attr_temp1_input.dev_attr.attr,	/* 0 */
···
 	&sensor_dev_attr_fan2_input.dev_attr.attr,	/* 11 */
 	&sensor_dev_attr_fan2_label.dev_attr.attr,	/* 12 */
 	&sensor_dev_attr_pwm2.dev_attr.attr,		/* 13 */
+	&sensor_dev_attr_fan3_input.dev_attr.attr,	/* 14 */
+	&sensor_dev_attr_fan3_label.dev_attr.attr,	/* 15 */
+	&sensor_dev_attr_pwm3.dev_attr.attr,		/* 16 */
 	NULL
 };
 
···
 			      int index)
 {
 	if (disallow_fan_type_call &&
-	    (index == 9 || index == 12))
+	    (index == 9 || index == 12 || index == 15))
 		return 0;
 	if (index >= 0 && index <= 1 &&
 	    !(i8k_hwmon_flags & I8K_HWMON_HAVE_TEMP1))
···
 		return 0;
 	if (index >= 11 && index <= 13 &&
 	    !(i8k_hwmon_flags & I8K_HWMON_HAVE_FAN2))
+		return 0;
+	if (index >= 14 && index <= 16 &&
+	    !(i8k_hwmon_flags & I8K_HWMON_HAVE_FAN3))
 		return 0;
 
 	return attr->mode;
···
 		err = i8k_get_fan_type(1);
 	if (err >= 0)
 		i8k_hwmon_flags |= I8K_HWMON_HAVE_FAN2;
+
+	/* Third fan attributes, if fan status or type is OK */
+	err = i8k_get_fan_status(2);
+	if (err < 0)
+		err = i8k_get_fan_type(2);
+	if (err >= 0)
+		i8k_hwmon_flags |= I8K_HWMON_HAVE_FAN3;
 
 	i8k_hwmon_dev = hwmon_device_register_with_groups(NULL, "dell_smm",
 							  NULL, i8k_groups);

drivers/hwmon/emc6w201.c

···
 	if (verstep < 0 || (verstep & 0xF0) != 0xB0)
 		return -ENODEV;
 	if ((verstep & 0x0F) > 2) {
-		dev_dbg(&client->dev, "Unknwown EMC6W201 stepping %d\n",
+		dev_dbg(&client->dev, "Unknown EMC6W201 stepping %d\n",
 			verstep & 0x0F);
 		return -ENODEV;
 	}

drivers/hwmon/ftsteutates.c

···
+/*
+ * Support for the FTS Systemmonitoring Chip "Teutates"
+ *
+ * Copyright (C) 2016 Fujitsu Technology Solutions GmbH,
+ *		  Thilo Cestonaro <[e-mail]>
+ *
+ * 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 <linux/err.h>
+#include <linux/fs.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/jiffies.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/uaccess.h>
+#include <linux/watchdog.h>
+
+#define FTS_DEVICE_ID_REG		0x0000
+#define FTS_DEVICE_REVISION_REG		0x0001
+#define FTS_DEVICE_STATUS_REG		0x0004
+#define FTS_SATELLITE_STATUS_REG	0x0005
+#define FTS_EVENT_STATUS_REG		0x0006
+#define FTS_GLOBAL_CONTROL_REG		0x0007
+
+#define FTS_SENSOR_EVENT_REG		0x0010
+
+#define FTS_FAN_EVENT_REG		0x0014
+#define FTS_FAN_PRESENT_REG		0x0015
+
+#define FTS_POWER_ON_TIME_COUNTER_A	0x007A
+#define FTS_POWER_ON_TIME_COUNTER_B	0x007B
+#define FTS_POWER_ON_TIME_COUNTER_C	0x007C
+
+#define FTS_PAGE_SELECT_REG		0x007F
+
+#define FTS_WATCHDOG_TIME_PRESET	0x000B
+#define FTS_WATCHDOG_CONTROL		0x5081
+
+#define FTS_NO_FAN_SENSORS		0x08
+#define FTS_NO_TEMP_SENSORS		0x10
+#define FTS_NO_VOLT_SENSORS		0x04
+
+static struct i2c_device_id fts_id[] = {
+	{ "ftsteutates", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, fts_id);
+
+enum WATCHDOG_RESOLUTION {
+	seconds = 1,
+	minutes = 60
+};
+
+struct fts_data {
+	struct i2c_client *client;
+	/* update sensor data lock */
+	struct mutex update_lock;
+	/* read/write register lock */
+	struct mutex access_lock;
+	unsigned long last_updated; /* in jiffies */
+	struct watchdog_device wdd;
+	enum WATCHDOG_RESOLUTION resolution;
+	bool valid; /* false until following fields are valid */
+
+	u8 volt[FTS_NO_VOLT_SENSORS];
+
+	u8 temp_input[FTS_NO_TEMP_SENSORS];
+	u8 temp_alarm;
+
+	u8 fan_present;
+	u8 fan_input[FTS_NO_FAN_SENSORS]; /* in rps */
+	u8 fan_source[FTS_NO_FAN_SENSORS];
+	u8 fan_alarm;
+};
+
+#define FTS_REG_FAN_INPUT(idx) ((idx) + 0x20)
+#define FTS_REG_FAN_SOURCE(idx) ((idx) + 0x30)
+#define FTS_REG_FAN_CONTROL(idx) (((idx) << 16) + 0x4881)
+
+#define FTS_REG_TEMP_INPUT(idx) ((idx) + 0x40)
+#define FTS_REG_TEMP_CONTROL(idx) (((idx) << 16) + 0x0681)
+
+#define FTS_REG_VOLT(idx) ((idx) + 0x18)
+
+/*****************************************************************************/
+/* I2C Helper functions							     */
+/*****************************************************************************/
+static int fts_read_byte(struct i2c_client *client, unsigned short reg)
+{
+	int ret;
+	unsigned char page = reg >> 8;
+	struct fts_data *data = dev_get_drvdata(&client->dev);
+
+	mutex_lock(&data->access_lock);
+
+	dev_dbg(&client->dev, "page select - page: 0x%.02x\n", page);
+	ret = i2c_smbus_write_byte_data(client, FTS_PAGE_SELECT_REG, page);
+	if (ret < 0)
+		goto error;
+
+	reg &= 0xFF;
+	ret = i2c_smbus_read_byte_data(client, reg);
+	dev_dbg(&client->dev, "read - reg: 0x%.02x: val: 0x%.02x\n", reg, ret);
+
+error:
+	mutex_unlock(&data->access_lock);
+	return ret;
+}
+
+static int fts_write_byte(struct i2c_client *client, unsigned short reg,
+			  unsigned char value)
+{
+	int ret;
+	unsigned char page = reg >> 8;
+	struct fts_data *data = dev_get_drvdata(&client->dev);
+
+	mutex_lock(&data->access_lock);
+
+	dev_dbg(&client->dev, "page select - page: 0x%.02x\n", page);
+	ret = i2c_smbus_write_byte_data(client, FTS_PAGE_SELECT_REG, page);
+	if (ret < 0)
+		goto error;
+
+	reg &= 0xFF;
+	dev_dbg(&client->dev,
+		"write - reg: 0x%.02x: val: 0x%.02x\n", reg, value);
+	ret = i2c_smbus_write_byte_data(client, reg, value);
+
+error:
+	mutex_unlock(&data->access_lock);
+	return ret;
+}
+
+/*****************************************************************************/
+/* Data Updater Helper function						     */
+/*****************************************************************************/
+static int fts_update_device(struct fts_data *data)
+{
+	int i;
+	int err = 0;
+
+	mutex_lock(&data->update_lock);
+	if (!time_after(jiffies, data->last_updated + 2 * HZ) && data->valid)
+		goto exit;
+
+	err = fts_read_byte(data->client, FTS_DEVICE_STATUS_REG);
+	if (err < 0)
+		goto exit;
+
+	data->valid = !!(err & 0x02); /* Data not ready yet */
+	if (unlikely(!data->valid)) {
+		err = -EAGAIN;
+		goto exit;
+	}
+
+	err = fts_read_byte(data->client, FTS_FAN_PRESENT_REG);
+	if (err < 0)
+		goto exit;
+	data->fan_present = err;
+
+	err = fts_read_byte(data->client, FTS_FAN_EVENT_REG);
+	if (err < 0)
+		goto exit;
+	data->fan_alarm = err;
+
+	for (i = 0; i < FTS_NO_FAN_SENSORS; i++) {
+		if (data->fan_present & BIT(i)) {
+			err = fts_read_byte(data->client, FTS_REG_FAN_INPUT(i));
+			if (err < 0)
+				goto exit;
+			data->fan_input[i] = err;
+
+			err = fts_read_byte(data->client,
+					    FTS_REG_FAN_SOURCE(i));
+			if (err < 0)
+				goto exit;
+			data->fan_source[i] = err;
+		} else {
+			data->fan_input[i] = 0;
+			data->fan_source[i] = 0;
+		}
+	}
+
+	err = fts_read_byte(data->client, FTS_SENSOR_EVENT_REG);
+	if (err < 0)
+		goto exit;
+	data->temp_alarm = err;
+
+	for (i = 0; i < FTS_NO_TEMP_SENSORS; i++) {
+		err = fts_read_byte(data->client, FTS_REG_TEMP_INPUT(i));
+		if (err < 0)
+			goto exit;
+		data->temp_input[i] = err;
+	}
+
+	for (i = 0; i < FTS_NO_VOLT_SENSORS; i++) {
+		err = fts_read_byte(data->client, FTS_REG_VOLT(i));
+		if (err < 0)
+			goto exit;
+		data->volt[i] = err;
+	}
+	data->last_updated = jiffies;
+	err = 0;
+exit:
+	mutex_unlock(&data->update_lock);
+	return err;
+}
+
+/*****************************************************************************/
+/* Watchdog functions							     */
+/*****************************************************************************/
+static int fts_wd_set_resolution(struct fts_data *data,
+				 enum WATCHDOG_RESOLUTION resolution)
+{
+	int ret;
+
+	if (data->resolution == resolution)
+		return 0;
+
+	ret = fts_read_byte(data->client, FTS_WATCHDOG_CONTROL);
+	if (ret < 0)
+		return ret;
+
+	if ((resolution == seconds && ret & BIT(1)) ||
+	    (resolution == minutes && (ret & BIT(1)) == 0)) {
+		data->resolution = resolution;
+		return 0;
+	}
+
+	if (resolution == seconds)
+		set_bit(1, (unsigned long *)&ret);
+	else
+		ret &= ~BIT(1);
+
+	ret = fts_write_byte(data->client, FTS_WATCHDOG_CONTROL, ret);
+	if (ret < 0)
+		return ret;
+
+	data->resolution = resolution;
+	return ret;
+}
+
+static int fts_wd_set_timeout(struct watchdog_device *wdd, unsigned int timeout)
+{
+	struct fts_data *data;
+	enum WATCHDOG_RESOLUTION resolution = seconds;
+	int ret;
+
+	data = watchdog_get_drvdata(wdd);
+	/* switch watchdog resolution to minutes if timeout does not fit
+	 * into a byte
+	 */
+	if (timeout > 0xFF) {
+		timeout = DIV_ROUND_UP(timeout, 60) * 60;
+		resolution = minutes;
+	}
+
+	ret = fts_wd_set_resolution(data, resolution);
+	if (ret < 0)
+		return ret;
+
+	wdd->timeout = timeout;
+	return 0;
+}
+
+static int fts_wd_start(struct watchdog_device *wdd)
+{
+	struct fts_data *data = watchdog_get_drvdata(wdd);
+
+	return fts_write_byte(data->client, FTS_WATCHDOG_TIME_PRESET,
+			      wdd->timeout / (u8)data->resolution);
+}
+
+static int fts_wd_stop(struct watchdog_device *wdd)
+{
+	struct fts_data *data;
+
+	data = watchdog_get_drvdata(wdd);
+	return fts_write_byte(data->client, FTS_WATCHDOG_TIME_PRESET, 0);
+}
+
+static const struct watchdog_info fts_wd_info = {
+	.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
+	.identity = "FTS Teutates Hardware Watchdog",
+};
+
+static const struct watchdog_ops fts_wd_ops = {
+	.owner = THIS_MODULE,
+	.start = fts_wd_start,
+	.stop = fts_wd_stop,
+	.set_timeout = fts_wd_set_timeout,
+};
+
+static int fts_watchdog_init(struct fts_data *data)
+{
+	int timeout, ret;
+
+	watchdog_set_drvdata(&data->wdd, data);
+
+	timeout = fts_read_byte(data->client, FTS_WATCHDOG_TIME_PRESET);
+	if (timeout < 0)
+		return timeout;
+
+	/* watchdog not running, set timeout to a default of 60 sec. */
+	if (timeout == 0) {
+		ret = fts_wd_set_resolution(data, seconds);
+		if (ret < 0)
+			return ret;
+		data->wdd.timeout = 60;
+	} else {
+		ret = fts_read_byte(data->client, FTS_WATCHDOG_CONTROL);
+		if (ret < 0)
+			return ret;
+
+		data->resolution = ret & BIT(1) ? seconds : minutes;
+		data->wdd.timeout = timeout * (u8)data->resolution;
+		set_bit(WDOG_HW_RUNNING, &data->wdd.status);
+	}
+
+	/* Register our watchdog part */
+	data->wdd.info = &fts_wd_info;
+	data->wdd.ops = &fts_wd_ops;
+	data->wdd.parent = &data->client->dev;
+	data->wdd.min_timeout = 1;
+
+	/* max timeout 255 minutes. */
+	data->wdd.max_hw_heartbeat_ms = 0xFF * 60 * MSEC_PER_SEC;
+
+	return watchdog_register_device(&data->wdd);
+}
+
+/*****************************************************************************/
+/* SysFS handler functions						     */
+/*****************************************************************************/
+static ssize_t show_in_value(struct device *dev,
+			     struct device_attribute *devattr, char *buf)
+{
+	struct fts_data *data = dev_get_drvdata(dev);
+	int index = to_sensor_dev_attr(devattr)->index;
+	int err;
+
+	err = fts_update_device(data);
+	if (err < 0)
+		return err;
+
+	return sprintf(buf, "%u\n", data->volt[index]);
+}
+
+static ssize_t show_temp_value(struct device *dev,
+			       struct device_attribute *devattr, char *buf)
+{
+	struct fts_data *data = dev_get_drvdata(dev);
+	int index = to_sensor_dev_attr(devattr)->index;
+	int err;
+
+	err = fts_update_device(data);
+	if (err < 0)
+		return err;
+
+	return sprintf(buf, "%u\n", data->temp_input[index]);
+}
+
+static ssize_t show_temp_fault(struct device *dev,
+			       struct device_attribute *devattr, char *buf)
+{
+	struct fts_data *data = dev_get_drvdata(dev);
+	int index = to_sensor_dev_attr(devattr)->index;
+	int err;
+
+	err = fts_update_device(data);
+	if (err < 0)
+		return err;
+
+	/* 00h Temperature = Sensor Error */
+	return sprintf(buf, "%d\n", data->temp_input[index] == 0);
+}
+
+static ssize_t show_temp_alarm(struct device *dev,
+			       struct device_attribute *devattr, char *buf)
+{
+	struct fts_data *data = dev_get_drvdata(dev);
+	int index = to_sensor_dev_attr(devattr)->index;
+	int err;
+
+	err = fts_update_device(data);
+	if (err < 0)
+		return err;
+
+	return sprintf(buf, "%u\n", !!(data->temp_alarm & BIT(index)));
+}
+
+static ssize_t
+clear_temp_alarm(struct device *dev, struct device_attribute *devattr,
+		 const char *buf, size_t count)
+{
+	struct fts_data *data = dev_get_drvdata(dev);
+	int index = to_sensor_dev_attr(devattr)->index;
+	long ret;
+
+	ret = fts_update_device(data);
+	if (ret < 0)
+		return ret;
+
+	if (kstrtoul(buf, 10, &ret) || ret != 0)
+		return -EINVAL;
+
+	mutex_lock(&data->update_lock);
+	ret = fts_read_byte(data->client, FTS_REG_TEMP_CONTROL(index));
+	if (ret < 0)
+		goto error;
+
+	ret = fts_write_byte(data->client, FTS_REG_TEMP_CONTROL(index),
+			     ret | 0x1);
+	if (ret < 0)
+		goto error;
+
+	data->valid = false;
+error:
+	mutex_unlock(&data->update_lock);
+	return ret;
+}
+
+static ssize_t show_fan_value(struct device *dev,
+			      struct device_attribute *devattr, char *buf)
+{
+	struct fts_data *data = dev_get_drvdata(dev);
+	int index = to_sensor_dev_attr(devattr)->index;
+	int err;
+
+	err = fts_update_device(data);
+	if (err < 0)
+		return err;
+
+	return sprintf(buf, "%u\n", data->fan_input[index]);
+}
+
+static ssize_t show_fan_source(struct device *dev,
+			       struct device_attribute *devattr, char *buf)
+{
+	struct fts_data *data = dev_get_drvdata(dev);
+	int index = to_sensor_dev_attr(devattr)->index;
+	int err;
+
+	err = fts_update_device(data);
+	if (err < 0)
+		return err;
+
+	return sprintf(buf, "%u\n", data->fan_source[index]);
+}
+
+static ssize_t show_fan_alarm(struct device *dev,
+			      struct device_attribute *devattr, char *buf)
+{
+	struct fts_data *data = dev_get_drvdata(dev);
+	int index = to_sensor_dev_attr(devattr)->index;
+	int err;
+
+	err = fts_update_device(data);
+	if (err < 0)
+		return err;
+
+	return sprintf(buf, "%d\n", !!(data->fan_alarm & BIT(index)));
+}
+
+static ssize_t
+clear_fan_alarm(struct device *dev, struct device_attribute *devattr,
+		const char *buf, size_t count)
+{
+	struct fts_data *data = dev_get_drvdata(dev);
+	int index = to_sensor_dev_attr(devattr)->index;
+	long ret;
+
+	ret = fts_update_device(data);
+	if (ret < 0)
+		return ret;
+
+	if (kstrtoul(buf, 10, &ret) || ret != 0)
+		return -EINVAL;
+
+	mutex_lock(&data->update_lock);
+	ret = fts_read_byte(data->client, FTS_REG_FAN_CONTROL(index));
+	if (ret < 0)
+		goto error;
+
+	ret = fts_write_byte(data->client, FTS_REG_FAN_CONTROL(index),
+			     ret | 0x1);
+	if (ret < 0)
+		goto error;
+
+	data->valid = false;
+error:
+	mutex_unlock(&data->update_lock);
+	return ret;
+}
+
+/*****************************************************************************/
+/* SysFS structs							     */
+/*****************************************************************************/
+
+/* Temprature sensors */
+static SENSOR_DEVICE_ATTR(temp1_input,  S_IRUGO, show_temp_value, NULL, 0);
+static SENSOR_DEVICE_ATTR(temp2_input,  S_IRUGO, show_temp_value, NULL, 1);
+static SENSOR_DEVICE_ATTR(temp3_input,  S_IRUGO, show_temp_value, NULL, 2);
+static SENSOR_DEVICE_ATTR(temp4_input,  S_IRUGO, show_temp_value, NULL, 3);
+static SENSOR_DEVICE_ATTR(temp5_input,  S_IRUGO, show_temp_value, NULL, 4);
+static SENSOR_DEVICE_ATTR(temp6_input,  S_IRUGO, show_temp_value, NULL, 5);
+static SENSOR_DEVICE_ATTR(temp7_input,  S_IRUGO, show_temp_value, NULL, 6);
+static SENSOR_DEVICE_ATTR(temp8_input,  S_IRUGO, show_temp_value, NULL, 7);
+static SENSOR_DEVICE_ATTR(temp9_input,  S_IRUGO, show_temp_value, NULL, 8);
+static SENSOR_DEVICE_ATTR(temp10_input, S_IRUGO, show_temp_value, NULL, 9);
+static SENSOR_DEVICE_ATTR(temp11_input, S_IRUGO, show_temp_value, NULL, 10);
+static SENSOR_DEVICE_ATTR(temp12_input, S_IRUGO, show_temp_value, NULL, 11);
+static SENSOR_DEVICE_ATTR(temp13_input, S_IRUGO, show_temp_value, NULL, 12);
+static SENSOR_DEVICE_ATTR(temp14_input, S_IRUGO, show_temp_value, NULL, 13);
+static SENSOR_DEVICE_ATTR(temp15_input, S_IRUGO, show_temp_value, NULL, 14);
+static SENSOR_DEVICE_ATTR(temp16_input, S_IRUGO, show_temp_value, NULL, 15);
+
+static SENSOR_DEVICE_ATTR(temp1_fault,  S_IRUGO, show_temp_fault, NULL, 0);
+static SENSOR_DEVICE_ATTR(temp2_fault,  S_IRUGO, show_temp_fault, NULL, 1);
+static SENSOR_DEVICE_ATTR(temp3_fault,  S_IRUGO, show_temp_fault, NULL, 2);
+static SENSOR_DEVICE_ATTR(temp4_fault,  S_IRUGO, show_temp_fault, NULL, 3);
+static SENSOR_DEVICE_ATTR(temp5_fault,  S_IRUGO, show_temp_fault, NULL, 4);
+static SENSOR_DEVICE_ATTR(temp6_fault,  S_IRUGO, show_temp_fault, NULL, 5);
+static SENSOR_DEVICE_ATTR(temp7_fault,  S_IRUGO, show_temp_fault, NULL, 6);
+static SENSOR_DEVICE_ATTR(temp8_fault,  S_IRUGO, show_temp_fault, NULL, 7);
+static SENSOR_DEVICE_ATTR(temp9_fault,  S_IRUGO, show_temp_fault, NULL, 8);
+static SENSOR_DEVICE_ATTR(temp10_fault, S_IRUGO, show_temp_fault, NULL, 9);
+static SENSOR_DEVICE_ATTR(temp11_fault, S_IRUGO, show_temp_fault, NULL, 10);
+static SENSOR_DEVICE_ATTR(temp12_fault, S_IRUGO, show_temp_fault, NULL, 11);
+static SENSOR_DEVICE_ATTR(temp13_fault, S_IRUGO, show_temp_fault, NULL, 12);
+static SENSOR_DEVICE_ATTR(temp14_fault, S_IRUGO, show_temp_fault, NULL, 13);
+static SENSOR_DEVICE_ATTR(temp15_fault, S_IRUGO, show_temp_fault, NULL, 14);
+static SENSOR_DEVICE_ATTR(temp16_fault, S_IRUGO, show_temp_fault, NULL, 15);
+
+static SENSOR_DEVICE_ATTR(temp1_alarm, S_IRUGO | S_IWUSR, show_temp_alarm,
+			  clear_temp_alarm, 0);
+static SENSOR_DEVICE_ATTR(temp2_alarm, S_IRUGO | S_IWUSR, show_temp_alarm,
+			  clear_temp_alarm, 1);
+static SENSOR_DEVICE_ATTR(temp3_alarm, S_IRUGO | S_IWUSR, show_temp_alarm,
+			  clear_temp_alarm, 2);
+static SENSOR_DEVICE_ATTR(temp4_alarm, S_IRUGO | S_IWUSR, show_temp_alarm,
+			  clear_temp_alarm, 3);
+static SENSOR_DEVICE_ATTR(temp5_alarm, S_IRUGO | S_IWUSR, show_temp_alarm,
+			  clear_temp_alarm, 4);
+static SENSOR_DEVICE_ATTR(temp6_alarm, S_IRUGO | S_IWUSR, show_temp_alarm,
+			  clear_temp_alarm, 5);
+static SENSOR_DEVICE_ATTR(temp7_alarm, S_IRUGO | S_IWUSR, show_temp_alarm,
+			  clear_temp_alarm, 6);
+static SENSOR_DEVICE_ATTR(temp8_alarm, S_IRUGO | S_IWUSR, show_temp_alarm,
+			  clear_temp_alarm, 7);
+static SENSOR_DEVICE_ATTR(temp9_alarm, S_IRUGO | S_IWUSR, show_temp_alarm,
+			  clear_temp_alarm, 8);
+static SENSOR_DEVICE_ATTR(temp10_alarm, S_IRUGO | S_IWUSR, show_temp_alarm,
+			  clear_temp_alarm, 9);
+static SENSOR_DEVICE_ATTR(temp11_alarm, S_IRUGO | S_IWUSR, show_temp_alarm,
+			  clear_temp_alarm, 10);
+static SENSOR_DEVICE_ATTR(temp12_alarm, S_IRUGO | S_IWUSR, show_temp_alarm,
+			  clear_temp_alarm, 11);
+static SENSOR_DEVICE_ATTR(temp13_alarm, S_IRUGO | S_IWUSR, show_temp_alarm,
+			  clear_temp_alarm, 12);
+static SENSOR_DEVICE_ATTR(temp14_alarm, S_IRUGO | S_IWUSR, show_temp_alarm,
+			  clear_temp_alarm, 13);
+static SENSOR_DEVICE_ATTR(temp15_alarm, S_IRUGO | S_IWUSR, show_temp_alarm,
+			  clear_temp_alarm, 14);
+static SENSOR_DEVICE_ATTR(temp16_alarm, S_IRUGO | S_IWUSR, show_temp_alarm,
+			  clear_temp_alarm, 15);
+
+static struct attribute *fts_temp_attrs[] = {
+	&sensor_dev_attr_temp1_input.dev_attr.attr,
+	&sensor_dev_attr_temp2_input.dev_attr.attr,
+	&sensor_dev_attr_temp3_input.dev_attr.attr,
+	&sensor_dev_attr_temp4_input.dev_attr.attr,
+	&sensor_dev_attr_temp5_input.dev_attr.attr,
+	&sensor_dev_attr_temp6_input.dev_attr.attr,
+	&sensor_dev_attr_temp7_input.dev_attr.attr,
+	&sensor_dev_attr_temp8_input.dev_attr.attr,
+	&sensor_dev_attr_temp9_input.dev_attr.attr,
+	&sensor_dev_attr_temp10_input.dev_attr.attr,
+	&sensor_dev_attr_temp11_input.dev_attr.attr,
+	&sensor_dev_attr_temp12_input.dev_attr.attr,
+	&sensor_dev_attr_temp13_input.dev_attr.attr,
+	&sensor_dev_attr_temp14_input.dev_attr.attr,
+	&sensor_dev_attr_temp15_input.dev_attr.attr,
+	&sensor_dev_attr_temp16_input.dev_attr.attr,
+
+	&sensor_dev_attr_temp1_fault.dev_attr.attr,
+	&sensor_dev_attr_temp2_fault.dev_attr.attr,
+	&sensor_dev_attr_temp3_fault.dev_attr.attr,
+	&sensor_dev_attr_temp4_fault.dev_attr.attr,
+	&sensor_dev_attr_temp5_fault.dev_attr.attr,
+	&sensor_dev_attr_temp6_fault.dev_attr.attr,
+	&sensor_dev_attr_temp7_fault.dev_attr.attr,
+	&sensor_dev_attr_temp8_fault.dev_attr.attr,
+	&sensor_dev_attr_temp9_fault.dev_attr.attr,
+	&sensor_dev_attr_temp10_fault.dev_attr.attr,
+	&sensor_dev_attr_temp11_fault.dev_attr.attr,
+	&sensor_dev_attr_temp12_fault.dev_attr.attr,
+	&sensor_dev_attr_temp13_fault.dev_attr.attr,
+	&sensor_dev_attr_temp14_fault.dev_attr.attr,
+	&sensor_dev_attr_temp15_fault.dev_attr.attr,
+	&sensor_dev_attr_temp16_fault.dev_attr.attr,
+
+	&sensor_dev_attr_temp1_alarm.dev_attr.attr,
+	&sensor_dev_attr_temp2_alarm.dev_attr.attr,
+	&sensor_dev_attr_temp3_alarm.dev_attr.attr,
+	&sensor_dev_attr_temp4_alarm.dev_attr.attr,
+	&sensor_dev_attr_temp5_alarm.dev_attr.attr,
+	&sensor_dev_attr_temp6_alarm.dev_attr.attr,
+	&sensor_dev_attr_temp7_alarm.dev_attr.attr,
+	&sensor_dev_attr_temp8_alarm.dev_attr.attr,
+	&sensor_dev_attr_temp9_alarm.dev_attr.attr,
+	&sensor_dev_attr_temp10_alarm.dev_attr.attr,
+	&sensor_dev_attr_temp11_alarm.dev_attr.attr,
+	&sensor_dev_attr_temp12_alarm.dev_attr.attr,
+	&sensor_dev_attr_temp13_alarm.dev_attr.attr,
+	&sensor_dev_attr_temp14_alarm.dev_attr.attr,
+	&sensor_dev_attr_temp15_alarm.dev_attr.attr,
+	&sensor_dev_attr_temp16_alarm.dev_attr.attr,
+	NULL
+};
+
+/* Fans */
+static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, show_fan_value, NULL, 0);
+static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, show_fan_value, NULL, 1);
+static SENSOR_DEVICE_ATTR(fan3_input, S_IRUGO, show_fan_value, NULL, 2);
+static SENSOR_DEVICE_ATTR(fan4_input, S_IRUGO, show_fan_value, NULL, 3);
+static SENSOR_DEVICE_ATTR(fan5_input, S_IRUGO, show_fan_value, NULL, 4);
+static SENSOR_DEVICE_ATTR(fan6_input, S_IRUGO, show_fan_value, NULL, 5);
+static SENSOR_DEVICE_ATTR(fan7_input, S_IRUGO, show_fan_value, NULL, 6);
+static SENSOR_DEVICE_ATTR(fan8_input, S_IRUGO, show_fan_value, NULL, 7);
+
+static SENSOR_DEVICE_ATTR(fan1_source, S_IRUGO, show_fan_source, NULL, 0);
+static SENSOR_DEVICE_ATTR(fan2_source, S_IRUGO, show_fan_source, NULL, 1);
+static SENSOR_DEVICE_ATTR(fan3_source, S_IRUGO, show_fan_source, NULL, 2);
+static SENSOR_DEVICE_ATTR(fan4_source, S_IRUGO, show_fan_source, NULL, 3);
+static SENSOR_DEVICE_ATTR(fan5_source, S_IRUGO, show_fan_source, NULL, 4);
+static SENSOR_DEVICE_ATTR(fan6_source, S_IRUGO, show_fan_source, NULL, 5);
+static SENSOR_DEVICE_ATTR(fan7_source, S_IRUGO, show_fan_source, NULL, 6);
+static SENSOR_DEVICE_ATTR(fan8_source, S_IRUGO, show_fan_source, NULL, 7);
+
+static SENSOR_DEVICE_ATTR(fan1_alarm, S_IRUGO | S_IWUSR,
+			 show_fan_alarm, clear_fan_alarm, 0);
+static SENSOR_DEVICE_ATTR(fan2_alarm, S_IRUGO | S_IWUSR,
+			 show_fan_alarm, clear_fan_alarm, 1);
+static SENSOR_DEVICE_ATTR(fan3_alarm, S_IRUGO | S_IWUSR,
+			 show_fan_alarm, clear_fan_alarm, 2);
+static SENSOR_DEVICE_ATTR(fan4_alarm, S_IRUGO | S_IWUSR,
+			 show_fan_alarm, clear_fan_alarm, 3);
+static SENSOR_DEVICE_ATTR(fan5_alarm, S_IRUGO | S_IWUSR,
+			 show_fan_alarm, clear_fan_alarm, 4);
+static SENSOR_DEVICE_ATTR(fan6_alarm, S_IRUGO | S_IWUSR,
+			 show_fan_alarm, clear_fan_alarm, 5);
+static SENSOR_DEVICE_ATTR(fan7_alarm, S_IRUGO | S_IWUSR,
+			 show_fan_alarm, clear_fan_alarm, 6);
+static SENSOR_DEVICE_ATTR(fan8_alarm, S_IRUGO | S_IWUSR,
+			 show_fan_alarm, clear_fan_alarm, 7);
+
+static struct attribute *fts_fan_attrs[] = {
+	&sensor_dev_attr_fan1_input.dev_attr.attr,
+	&sensor_dev_attr_fan2_input.dev_attr.attr,
+	&sensor_dev_attr_fan3_input.dev_attr.attr,
+	&sensor_dev_attr_fan4_input.dev_attr.attr,
+	&sensor_dev_attr_fan5_input.dev_attr.attr,
+	&sensor_dev_attr_fan6_input.dev_attr.attr,
+	&sensor_dev_attr_fan7_input.dev_attr.attr,
+	&sensor_dev_attr_fan8_input.dev_attr.attr,
+
+	&sensor_dev_attr_fan1_source.dev_attr.attr,
+	&sensor_dev_attr_fan2_source.dev_attr.attr,
+	&sensor_dev_attr_fan3_source.dev_attr.attr,
+	&sensor_dev_attr_fan4_source.dev_attr.attr,
+	&sensor_dev_attr_fan5_source.dev_attr.attr,
+	&sensor_dev_attr_fan6_source.dev_attr.attr,
+	&sensor_dev_attr_fan7_source.dev_attr.attr,
+	&sensor_dev_attr_fan8_source.dev_attr.attr,
+
+	&sensor_dev_attr_fan1_alarm.dev_attr.attr,
+	&sensor_dev_attr_fan2_alarm.dev_attr.attr,
+	&sensor_dev_attr_fan3_alarm.dev_attr.attr,
+	&sensor_dev_attr_fan4_alarm.dev_attr.attr,
+	&sensor_dev_attr_fan5_alarm.dev_attr.attr,
+	&sensor_dev_attr_fan6_alarm.dev_attr.attr,
+	&sensor_dev_attr_fan7_alarm.dev_attr.attr,
+	&sensor_dev_attr_fan8_alarm.dev_attr.attr,
+	NULL
+};
+
+/* Voltages */
+static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, show_in_value, NULL, 0);
+static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, show_in_value, NULL, 1);
+static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, show_in_value, NULL, 2);
+static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, show_in_value, NULL, 3);
+static struct attribute *fts_voltage_attrs[] = {
+	&sensor_dev_attr_in1_input.dev_attr.attr,
+	&sensor_dev_attr_in2_input.dev_attr.attr,
+	&sensor_dev_attr_in3_input.dev_attr.attr,
+	&sensor_dev_attr_in4_input.dev_attr.attr,
+	NULL
+};
+
+static const struct attribute_group fts_voltage_attr_group = {
+	.attrs = fts_voltage_attrs
+};
+
+static const struct attribute_group fts_temp_attr_group = {
+	.attrs = fts_temp_attrs
+};
+
+static const struct attribute_group fts_fan_attr_group = {
+	.attrs = fts_fan_attrs
+};
+
+static const struct attribute_group *fts_attr_groups[] = {
+	&fts_voltage_attr_group,
+	&fts_temp_attr_group,
+	&fts_fan_attr_group,
+	NULL
+};
+
+/*****************************************************************************/
+/* Module initialization / remove functions				     */
+/*****************************************************************************/
+static int fts_remove(struct i2c_client *client)
+{
+	struct fts_data *data = dev_get_drvdata(&client->dev);
+
+	watchdog_unregister_device(&data->wdd);
+	return 0;
+}
+
+static int fts_probe(struct i2c_client *client, const struct i2c_device_id *id)
+{
+	u8 revision;
+	struct fts_data *data;
+	int err;
+	s8 deviceid;
+	struct device *hwmon_dev;
+
+	if (client->addr != 0x73)
+		return -ENODEV;
+
+	/* Baseboard Management Controller check */
+	deviceid = i2c_smbus_read_byte_data(client, FTS_DEVICE_ID_REG);
+	if (deviceid > 0 && (deviceid & 0xF0) == 0x10) {
+		switch (deviceid & 0x0F) {
+		case 0x01:
+			break;
+		default:
+			dev_dbg(&client->dev,
+				"No Baseboard Management Controller\n");
+			return -ENODEV;
+		}
+	} else {
+		dev_dbg(&client->dev, "No fujitsu board\n");
+		return -ENODEV;
+	}
+
+	data = devm_kzalloc(&client->dev, sizeof(struct fts_data),
+			    GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	mutex_init(&data->update_lock);
+	mutex_init(&data->access_lock);
+	data->client = client;
+	dev_set_drvdata(&client->dev, data);
+
+	err = i2c_smbus_read_byte_data(client, FTS_DEVICE_REVISION_REG);
+	if (err < 0)
+		return err;
+	revision = err;
+
+	hwmon_dev = devm_hwmon_device_register_with_groups(&client->dev,
+							   "ftsteutates",
+							   data,
+							   fts_attr_groups);
+	if (IS_ERR(hwmon_dev))
+		return PTR_ERR(hwmon_dev);
+
+	err = fts_watchdog_init(data);
+	if (err)
+		return err;
+
+	dev_info(&client->dev, "Detected FTS Teutates chip, revision: %d.%d\n",
+		 (revision & 0xF0) >> 4, revision & 0x0F);
+	return 0;
+}
+
+/*****************************************************************************/
+/* Module Details							     */
+/*****************************************************************************/
+static struct i2c_driver fts_driver = {
+	.driver = {
+		.name = "ftsteutates",
+	},
+	.id_table = fts_id,
+	.probe = fts_probe,
+	.remove = fts_remove,
+};
+
+module_i2c_driver(fts_driver);
+
+MODULE_AUTHOR("Thilo Cestonaro <[e-mail]>");
+MODULE_DESCRIPTION("FTS Teutates driver");
+MODULE_LICENSE("GPL");

drivers/hwmon/ina3221.c

···
+/*
+ * INA3221 Triple Current/Voltage Monitor
+ *
+ * Copyright (C) 2016 Texas Instruments Incorporated - http://www.ti.com/
+ *	Andrew F. Davis <[e-mail]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 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 <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/regmap.h>
+
+#define INA3221_DRIVER_NAME		"ina3221"
+
+#define INA3221_CONFIG			0x00
+#define INA3221_SHUNT1			0x01
+#define INA3221_BUS1			0x02
+#define INA3221_SHUNT2			0x03
+#define INA3221_BUS2			0x04
+#define INA3221_SHUNT3			0x05
+#define INA3221_BUS3			0x06
+#define INA3221_CRIT1			0x07
+#define INA3221_WARN1			0x08
+#define INA3221_CRIT2			0x09
+#define INA3221_WARN2			0x0a
+#define INA3221_CRIT3			0x0b
+#define INA3221_WARN3			0x0c
+#define INA3221_MASK_ENABLE		0x0f
+
+#define INA3221_CONFIG_MODE_SHUNT	BIT(1)
+#define INA3221_CONFIG_MODE_BUS		BIT(2)
+#define INA3221_CONFIG_MODE_CONTINUOUS	BIT(3)
+
+#define INA3221_RSHUNT_DEFAULT		10000
+
+enum ina3221_fields {
+	/* Configuration */
+	F_RST,
+
+	/* Alert Flags */
+	F_WF3, F_WF2, F_WF1,
+	F_CF3, F_CF2, F_CF1,
+
+	/* sentinel */
+	F_MAX_FIELDS
+};
+
+static const struct reg_field ina3221_reg_fields[] = {
+	[F_RST] = REG_FIELD(INA3221_CONFIG, 15, 15),
+
+	[F_WF3] = REG_FIELD(INA3221_MASK_ENABLE, 3, 3),
+	[F_WF2] = REG_FIELD(INA3221_MASK_ENABLE, 4, 4),
+	[F_WF1] = REG_FIELD(INA3221_MASK_ENABLE, 5, 5),
+	[F_CF3] = REG_FIELD(INA3221_MASK_ENABLE, 7, 7),
+	[F_CF2] = REG_FIELD(INA3221_MASK_ENABLE, 8, 8),
+	[F_CF1] = REG_FIELD(INA3221_MASK_ENABLE, 9, 9),
+};
+
+enum ina3221_channels {
+	INA3221_CHANNEL1,
+	INA3221_CHANNEL2,
+	INA3221_CHANNEL3,
+	INA3221_NUM_CHANNELS
+};
+
+static const unsigned int register_channel[] = {
+	[INA3221_SHUNT1] = INA3221_CHANNEL1,
+	[INA3221_SHUNT2] = INA3221_CHANNEL2,
+	[INA3221_SHUNT3] = INA3221_CHANNEL3,
+	[INA3221_CRIT1] = INA3221_CHANNEL1,
+	[INA3221_CRIT2] = INA3221_CHANNEL2,
+	[INA3221_CRIT3] = INA3221_CHANNEL3,
+	[INA3221_WARN1] = INA3221_CHANNEL1,
+	[INA3221_WARN2] = INA3221_CHANNEL2,
+	[INA3221_WARN3] = INA3221_CHANNEL3,
+};
+
+/**
+ * struct ina3221_data - device specific information
+ * @regmap: Register map of the device
+ * @fields: Register fields of the device
+ * @shunt_resistors: Array of resistor values per channel
+ */
+struct ina3221_data {
+	struct regmap *regmap;
+	struct regmap_field *fields[F_MAX_FIELDS];
+	int shunt_resistors[INA3221_NUM_CHANNELS];
+};
+
+static int ina3221_read_value(struct ina3221_data *ina, unsigned int reg,
+			      int *val)
+{
+	unsigned int regval;
+	int ret;
+
+	ret = regmap_read(ina->regmap, reg, &regval);
+	if (ret)
+		return ret;
+
+	*val = sign_extend32(regval >> 3, 12);
+
+	return 0;
+}
+
+static ssize_t ina3221_show_bus_voltage(struct device *dev,
+					struct device_attribute *attr,
+					char *buf)
+{
+	struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr);
+	struct ina3221_data *ina = dev_get_drvdata(dev);
+	unsigned int reg = sd_attr->index;
+	int val, voltage_mv, ret;
+
+	ret = ina3221_read_value(ina, reg, &val);
+	if (ret)
+		return ret;
+
+	voltage_mv = val * 8;
+
+	return snprintf(buf, PAGE_SIZE, "%d\n", voltage_mv);
+}
+
+static ssize_t ina3221_show_shunt_voltage(struct device *dev,
+					  struct device_attribute *attr,
+					  char *buf)
+{
+	struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr);
+	struct ina3221_data *ina = dev_get_drvdata(dev);
+	unsigned int reg = sd_attr->index;
+	int val, voltage_uv, ret;
+
+	ret = ina3221_read_value(ina, reg, &val);
+	if (ret)
+		return ret;
+	voltage_uv = val * 40;
+
+	return snprintf(buf, PAGE_SIZE, "%d\n", voltage_uv);
+}
+
+static ssize_t ina3221_show_current(struct device *dev,
+				    struct device_attribute *attr, char *buf)
+{
+	struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr);
+	struct ina3221_data *ina = dev_get_drvdata(dev);
+	unsigned int reg = sd_attr->index;
+	unsigned int channel = register_channel[reg];
+	int resistance_uo = ina->shunt_resistors[channel];
+	int val, current_ma, voltage_nv, ret;
+
+	ret = ina3221_read_value(ina, reg, &val);
+	if (ret)
+		return ret;
+	voltage_nv = val * 40000;
+
+	current_ma = DIV_ROUND_CLOSEST(voltage_nv, resistance_uo);
+
+	return snprintf(buf, PAGE_SIZE, "%d\n", current_ma);
+}
+
+static ssize_t ina3221_set_current(struct device *dev,
+				   struct device_attribute *attr,
+				   const char *buf, size_t count)
+{
+	struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr);
+	struct ina3221_data *ina = dev_get_drvdata(dev);
+	unsigned int reg = sd_attr->index;
+	unsigned int channel = register_channel[reg];
+	int resistance_uo = ina->shunt_resistors[channel];
+	int val, current_ma, voltage_uv, ret;
+
+	ret = kstrtoint(buf, 0, &current_ma);
+	if (ret)
+		return ret;
+
+	/* clamp current */
+	current_ma = clamp_val(current_ma,
+			       INT_MIN / resistance_uo,
+			       INT_MAX / resistance_uo);
+
+	voltage_uv = DIV_ROUND_CLOSEST(current_ma * resistance_uo, 1000);
+
+	/* clamp voltage */
+	voltage_uv = clamp_val(voltage_uv, -163800, 163800);
+
+	/* 1 / 40uV(scale) << 3(register shift) = 5 */
+	val = DIV_ROUND_CLOSEST(voltage_uv, 5) & 0xfff8;
+
+	ret = regmap_write(ina->regmap, reg, val);
+	if (ret)
+		return ret;
+
+	return count;
+}
+
+static ssize_t ina3221_show_shunt(struct device *dev,
+				  struct device_attribute *attr, char *buf)
+{
+	struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr);
+	struct ina3221_data *ina = dev_get_drvdata(dev);
+	unsigned int channel = sd_attr->index;
+	unsigned int resistance_uo;
+
+	resistance_uo = ina->shunt_resistors[channel];
+
+	return snprintf(buf, PAGE_SIZE, "%d\n", resistance_uo);
+}
+
+static ssize_t ina3221_set_shunt(struct device *dev,
+				 struct device_attribute *attr,
+				 const char *buf, size_t count)
+{
+	struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr);
+	struct ina3221_data *ina = dev_get_drvdata(dev);
+	unsigned int channel = sd_attr->index;
+	int val;
+	int ret;
+
+	ret = kstrtoint(buf, 0, &val);
+	if (ret)
+		return ret;
+
+	val = clamp_val(val, 1, INT_MAX);
+
+	ina->shunt_resistors[channel] = val;
+
+	return count;
+}
+
+static ssize_t ina3221_show_alert(struct device *dev,
+				  struct device_attribute *attr, char *buf)
+{
+	struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr);
+	struct ina3221_data *ina = dev_get_drvdata(dev);
+	unsigned int field = sd_attr->index;
+	unsigned int regval;
+	int ret;
+
+	ret = regmap_field_read(ina->fields[field], &regval);
+	if (ret)
+		return ret;
+
+	return snprintf(buf, PAGE_SIZE, "%d\n", regval);
+}
+
+/* bus voltage */
+static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO,
+		ina3221_show_bus_voltage, NULL, INA3221_BUS1);
+static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO,
+		ina3221_show_bus_voltage, NULL, INA3221_BUS2);
+static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO,
+		ina3221_show_bus_voltage, NULL, INA3221_BUS3);
+
+/* calculated current */
+static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO,
+		ina3221_show_current, NULL, INA3221_SHUNT1);
+static SENSOR_DEVICE_ATTR(curr2_input, S_IRUGO,
+		ina3221_show_current, NULL, INA3221_SHUNT2);
+static SENSOR_DEVICE_ATTR(curr3_input, S_IRUGO,
+		ina3221_show_current, NULL, INA3221_SHUNT3);
+
+/* shunt resistance */
+static SENSOR_DEVICE_ATTR(shunt1_resistor, S_IRUGO | S_IWUSR,
+		ina3221_show_shunt, ina3221_set_shunt, INA3221_CHANNEL1);
+static SENSOR_DEVICE_ATTR(shunt2_resistor, S_IRUGO | S_IWUSR,
+		ina3221_show_shunt, ina3221_set_shunt, INA3221_CHANNEL2);
+static SENSOR_DEVICE_ATTR(shunt3_resistor, S_IRUGO | S_IWUSR,
+		ina3221_show_shunt, ina3221_set_shunt, INA3221_CHANNEL3);
+
+/* critical current */
+static SENSOR_DEVICE_ATTR(curr1_crit, S_IRUGO | S_IWUSR,
+		ina3221_show_current, ina3221_set_current, INA3221_CRIT1);
+static SENSOR_DEVICE_ATTR(curr2_crit, S_IRUGO | S_IWUSR,
+		ina3221_show_current, ina3221_set_current, INA3221_CRIT2);
+static SENSOR_DEVICE_ATTR(curr3_crit, S_IRUGO | S_IWUSR,
+		ina3221_show_current, ina3221_set_current, INA3221_CRIT3);
+
+/* critical current alert */
+static SENSOR_DEVICE_ATTR(curr1_crit_alarm, S_IRUGO,
+		ina3221_show_alert, NULL, F_CF1);
+static SENSOR_DEVICE_ATTR(curr2_crit_alarm, S_IRUGO,
+		ina3221_show_alert, NULL, F_CF2);
+static SENSOR_DEVICE_ATTR(curr3_crit_alarm, S_IRUGO,
+		ina3221_show_alert, NULL, F_CF3);
+
+/* warning current */
+static SENSOR_DEVICE_ATTR(curr1_max, S_IRUGO | S_IWUSR,
+		ina3221_show_current, ina3221_set_current, INA3221_WARN1);
+static SENSOR_DEVICE_ATTR(curr2_max, S_IRUGO | S_IWUSR,
+		ina3221_show_current, ina3221_set_current, INA3221_WARN2);
+static SENSOR_DEVICE_ATTR(curr3_max, S_IRUGO | S_IWUSR,
+		ina3221_show_current, ina3221_set_current, INA3221_WARN3);
+
+/* warning current alert */
+static SENSOR_DEVICE_ATTR(curr1_max_alarm, S_IRUGO,
+		ina3221_show_alert, NULL, F_WF1);
+static SENSOR_DEVICE_ATTR(curr2_max_alarm, S_IRUGO,
+		ina3221_show_alert, NULL, F_WF2);
+static SENSOR_DEVICE_ATTR(curr3_max_alarm, S_IRUGO,
+		ina3221_show_alert, NULL, F_WF3);
+
+/* shunt voltage */
+static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO,
+		ina3221_show_shunt_voltage, NULL, INA3221_SHUNT1);
+static SENSOR_DEVICE_ATTR(in5_input, S_IRUGO,
+		ina3221_show_shunt_voltage, NULL, INA3221_SHUNT2);
+static SENSOR_DEVICE_ATTR(in6_input, S_IRUGO,
+		ina3221_show_shunt_voltage, NULL, INA3221_SHUNT3);
+
+static struct attribute *ina3221_attrs[] = {
+	/* channel 1 */
+	&sensor_dev_attr_in1_input.dev_attr.attr,
+	&sensor_dev_attr_curr1_input.dev_attr.attr,
+	&sensor_dev_attr_shunt1_resistor.dev_attr.attr,
+	&sensor_dev_attr_curr1_crit.dev_attr.attr,
+	&sensor_dev_attr_curr1_crit_alarm.dev_attr.attr,
+	&sensor_dev_attr_curr1_max.dev_attr.attr,
+	&sensor_dev_attr_curr1_max_alarm.dev_attr.attr,
+	&sensor_dev_attr_in4_input.dev_attr.attr,
+
+	/* channel 2 */
+	&sensor_dev_attr_in2_input.dev_attr.attr,
+	&sensor_dev_attr_curr2_input.dev_attr.attr,
+	&sensor_dev_attr_shunt2_resistor.dev_attr.attr,
+	&sensor_dev_attr_curr2_crit.dev_attr.attr,
+	&sensor_dev_attr_curr2_crit_alarm.dev_attr.attr,
+	&sensor_dev_attr_curr2_max.dev_attr.attr,
+	&sensor_dev_attr_curr2_max_alarm.dev_attr.attr,
+	&sensor_dev_attr_in5_input.dev_attr.attr,
+
+	/* channel 3 */
+	&sensor_dev_attr_in3_input.dev_attr.attr,
+	&sensor_dev_attr_curr3_input.dev_attr.attr,
+	&sensor_dev_attr_shunt3_resistor.dev_attr.attr,
+	&sensor_dev_attr_curr3_crit.dev_attr.attr,
+	&sensor_dev_attr_curr3_crit_alarm.dev_attr.attr,
+	&sensor_dev_attr_curr3_max.dev_attr.attr,
+	&sensor_dev_attr_curr3_max_alarm.dev_attr.attr,
+	&sensor_dev_attr_in6_input.dev_attr.attr,
+
+	NULL,
+};
+ATTRIBUTE_GROUPS(ina3221);
+
+static const struct regmap_range ina3221_yes_ranges[] = {
+	regmap_reg_range(INA3221_SHUNT1, INA3221_BUS3),
+	regmap_reg_range(INA3221_MASK_ENABLE, INA3221_MASK_ENABLE),
+};
+
+static const struct regmap_access_table ina3221_volatile_table = {
+	.yes_ranges = ina3221_yes_ranges,
+	.n_yes_ranges = ARRAY_SIZE(ina3221_yes_ranges),
+};
+
+static const struct regmap_config ina3221_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 16,
+
+	.cache_type = REGCACHE_RBTREE,
+	.volatile_table = &ina3221_volatile_table,
+};
+
+static int ina3221_probe(struct i2c_client *client,
+			 const struct i2c_device_id *id)
+{
+	struct device *dev = &client->dev;
+	struct ina3221_data *ina;
+	struct device *hwmon_dev;
+	int i, ret;
+
+	ina = devm_kzalloc(dev, sizeof(*ina), GFP_KERNEL);
+	if (!ina)
+		return -ENOMEM;
+
+	ina->regmap = devm_regmap_init_i2c(client, &ina3221_regmap_config);
+	if (IS_ERR(ina->regmap)) {
+		dev_err(dev, "Unable to allocate register map\n");
+		return PTR_ERR(ina->regmap);
+	}
+
+	for (i = 0; i < F_MAX_FIELDS; i++) {
+		ina->fields[i] = devm_regmap_field_alloc(dev,
+							 ina->regmap,
+							 ina3221_reg_fields[i]);
+		if (IS_ERR(ina->fields[i])) {
+			dev_err(dev, "Unable to allocate regmap fields\n");
+			return PTR_ERR(ina->fields[i]);
+		}
+	}
+
+	for (i = 0; i < INA3221_NUM_CHANNELS; i++)
+		ina->shunt_resistors[i] = INA3221_RSHUNT_DEFAULT;
+
+	ret = regmap_field_write(ina->fields[F_RST], true);
+	if (ret) {
+		dev_err(dev, "Unable to reset device\n");
+		return ret;
+	}
+
+	hwmon_dev = devm_hwmon_device_register_with_groups(dev,
+							   client->name,
+							   ina, ina3221_groups);
+	if (IS_ERR(hwmon_dev)) {
+		dev_err(dev, "Unable to register hwmon device\n");
+		return PTR_ERR(hwmon_dev);
+	}
+
+	return 0;
+}
+
+static const struct of_device_id ina3221_of_match_table[] = {
+	{ .compatible = "ti,ina3221", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, ina3221_of_match_table);
+
+static const struct i2c_device_id ina3221_ids[] = {
+	{ "ina3221", 0 },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(i2c, ina3221_ids);
+
+static struct i2c_driver ina3221_i2c_driver = {
+	.probe = ina3221_probe,
+	.driver = {
+		.name = INA3221_DRIVER_NAME,
+		.of_match_table = ina3221_of_match_table,
+	},
+	.id_table = ina3221_ids,
+};
+module_i2c_driver(ina3221_i2c_driver);
+
+MODULE_AUTHOR("Andrew F. Davis <[e-mail]>");
+MODULE_DESCRIPTION("Texas Instruments INA3221 HWMon Driver");
+MODULE_LICENSE("GPL v2");

drivers/hwmon/jc42.c

···
 #include <linux/hwmon-sysfs.h>
 #include <linux/err.h>
 #include <linux/mutex.h>
+#include <linux/of.h>
 
 /* Addresses to scan */
 static const unsigned short normal_i2c[] = {
···
 #define MCP9804_DEVID		0x0200
 #define MCP9804_DEVID_MASK	0xfffc
 
+#define MCP9808_DEVID		0x0400
+#define MCP9808_DEVID_MASK	0xfffc
+
 #define MCP98242_DEVID		0x2000
 #define MCP98242_DEVID_MASK	0xfffc
 
···
 	{ IDT_MANID, TS3001_DEVID, TS3001_DEVID_MASK },
 	{ MAX_MANID, MAX6604_DEVID, MAX6604_DEVID_MASK },
 	{ MCP_MANID, MCP9804_DEVID, MCP9804_DEVID_MASK },
+	{ MCP_MANID, MCP9808_DEVID, MCP9808_DEVID_MASK },
 	{ MCP_MANID, MCP98242_DEVID, MCP98242_DEVID_MASK },
 	{ MCP_MANID, MCP98243_DEVID, MCP98243_DEVID_MASK },
 	{ MCP_MANID, MCP98244_DEVID, MCP98244_DEVID_MASK },
···
 };
 MODULE_DEVICE_TABLE(i2c, jc42_id);
 
+#ifdef CONFIG_OF
+static const struct of_device_id jc42_of_ids[] = {
+	{ .compatible = "jedec,jc-42.4-temp", },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, jc42_of_ids);
+#endif
+
 static struct i2c_driver jc42_driver = {
-	.class		= I2C_CLASS_SPD,
+	.class		= I2C_CLASS_SPD | I2C_CLASS_HWMON,
 	.driver = {
 		.name	= "jc42",
 		.pm = JC42_DEV_PM_OPS,
+		.of_match_table = of_match_ptr(jc42_of_ids),
 	},
 	.probe		= jc42_probe,
 	.remove		= jc42_remove,

drivers/hwmon/jz4740-hwmon.c

···
 
 struct jz4740_hwmon {
 	void __iomem *base;
-
 	int irq;
-
 	const struct mfd_cell *cell;
-	struct device *hwmon;
-
+	struct platform_device *pdev;
 	struct completion read_completion;
-
 	struct mutex lock;
 };
-
-static ssize_t jz4740_hwmon_show_name(struct device *dev,
-	struct device_attribute *dev_attr, char *buf)
-{
-	return sprintf(buf, "jz4740\n");
-}
 
 static irqreturn_t jz4740_hwmon_irq(int irq, void *data)
 {
···
 	struct device_attribute *dev_attr, char *buf)
 {
 	struct jz4740_hwmon *hwmon = dev_get_drvdata(dev);
+	struct platform_device *pdev = hwmon->pdev;
 	struct completion *completion = &hwmon->read_completion;
 	long t;
 	unsigned long val;
···
 	reinit_completion(completion);
 
 	enable_irq(hwmon->irq);
-	hwmon->cell->enable(to_platform_device(dev));
+	hwmon->cell->enable(pdev);
 
 	t = wait_for_completion_interruptible_timeout(completion, HZ);
 
···
 		ret = t ? t : -ETIMEDOUT;
 	}
 
-	hwmon->cell->disable(to_platform_device(dev));
+	hwmon->cell->disable(pdev);
 	disable_irq(hwmon->irq);
 
 	mutex_unlock(&hwmon->lock);
···
 	return ret;
 }
 
-static DEVICE_ATTR(name, S_IRUGO, jz4740_hwmon_show_name, NULL);
 static DEVICE_ATTR(in0_input, S_IRUGO, jz4740_hwmon_read_adcin, NULL);
 
-static struct attribute *jz4740_hwmon_attributes[] = {
-	&dev_attr_name.attr,
+static struct attribute *jz4740_attrs[] = {
 	&dev_attr_in0_input.attr,
 	NULL
 };
 
-static const struct attribute_group jz4740_hwmon_attr_group = {
-	.attrs = jz4740_hwmon_attributes,
-};
+ATTRIBUTE_GROUPS(jz4740);
 
 static int jz4740_hwmon_probe(struct platform_device *pdev)
 {
 	int ret;
+	struct device *dev = &pdev->dev;
 	struct jz4740_hwmon *hwmon;
+	struct device *hwmon_dev;
 	struct resource *mem;
 
-	hwmon = devm_kzalloc(&pdev->dev, sizeof(*hwmon), GFP_KERNEL);
+	hwmon = devm_kzalloc(dev, sizeof(*hwmon), GFP_KERNEL);
 	if (!hwmon)
 		return -ENOMEM;
 
···
 	if (IS_ERR(hwmon->base))
 		return PTR_ERR(hwmon->base);
 
+	hwmon->pdev = pdev;
 	init_completion(&hwmon->read_completion);
 	mutex_init(&hwmon->lock);
 
-	platform_set_drvdata(pdev, hwmon);
-
-	ret = devm_request_irq(&pdev->dev, hwmon->irq, jz4740_hwmon_irq, 0,
+	ret = devm_request_irq(dev, hwmon->irq, jz4740_hwmon_irq, 0,
 			       pdev->name, hwmon);
 	if (ret) {
 		dev_err(&pdev->dev, "Failed to request irq: %d\n", ret);
···
 	}
 	disable_irq(hwmon->irq);
 
-	ret = sysfs_create_group(&pdev->dev.kobj, &jz4740_hwmon_attr_group);
-	if (ret) {
-		dev_err(&pdev->dev, "Failed to create sysfs group: %d\n", ret);
-		return ret;
-	}
-
-	hwmon->hwmon = hwmon_device_register(&pdev->dev);
-	if (IS_ERR(hwmon->hwmon)) {
-		ret = PTR_ERR(hwmon->hwmon);
-		goto err_remove_file;
-	}
-
-	return 0;
-
-err_remove_file:
-	sysfs_remove_group(&pdev->dev.kobj, &jz4740_hwmon_attr_group);
-	return ret;
-}
-
-static int jz4740_hwmon_remove(struct platform_device *pdev)
-{
-	struct jz4740_hwmon *hwmon = platform_get_drvdata(pdev);
-
-	hwmon_device_unregister(hwmon->hwmon);
-	sysfs_remove_group(&pdev->dev.kobj, &jz4740_hwmon_attr_group);
-
-	return 0;
+	hwmon_dev = devm_hwmon_device_register_with_groups(dev, "jz4740", hwmon,
+							   jz4740_groups);
+	return PTR_ERR_OR_ZERO(hwmon_dev);
 }
 
 static struct platform_driver jz4740_hwmon_driver = {
 	.probe	= jz4740_hwmon_probe,
-	.remove = jz4740_hwmon_remove,
 	.driver = {
 		.name = "jz4740-hwmon",
 	},

drivers/hwmon/lm75.c

···
 #include <linux/hwmon.h>
 #include <linux/hwmon-sysfs.h>
 #include <linux/err.h>
-#include <linux/mutex.h>
 #include <linux/of.h>
+#include <linux/regmap.h>
 #include <linux/thermal.h>
 #include "lm75.h"
 
···
 
 
 /* The LM75 registers */
+#define LM75_REG_TEMP		0x00
 #define LM75_REG_CONF		0x01
-static const u8 LM75_REG_TEMP[3] = {
-	0x00,		/* input */
-	0x03,		/* max */
-	0x02,		/* hyst */
-};
+#define LM75_REG_HYST		0x02
+#define LM75_REG_MAX		0x03
 
 /* Each client has this additional data */
 struct lm75_data {
 	struct i2c_client	*client;
-	struct device		*hwmon_dev;
-	struct mutex		update_lock;
+	struct regmap		*regmap;
 	u8			orig_conf;
 	u8			resolution;	/* In bits, between 9 and 12 */
 	u8			resolution_limits;
-	char			valid;		/* !=0 if registers are valid */
-	unsigned long		last_updated;	/* In jiffies */
-	unsigned long		sample_time;	/* In jiffies */
-	s16			temp[3];	/* Register values,
-						   0 = input
-						   1 = max
-						   2 = hyst */
+	unsigned int		sample_time;	/* In ms */
 };
-
-static int lm75_read_value(struct i2c_client *client, u8 reg);
-static int lm75_write_value(struct i2c_client *client, u8 reg, u16 value);
-static struct lm75_data *lm75_update_device(struct device *dev);
-
 
 /*-----------------------------------------------------------------------*/
 
···
 
 static int lm75_read_temp(void *dev, int *temp)
 {
-	struct lm75_data *data = lm75_update_device(dev);
+	struct lm75_data *data = dev_get_drvdata(dev);
+	unsigned int _temp;
+	int err;
 
-	if (IS_ERR(data))
-		return PTR_ERR(data);
+	err = regmap_read(data->regmap, LM75_REG_TEMP, &_temp);
+	if (err < 0)
+		return err;
 
-	*temp = lm75_reg_to_mc(data->temp[0], data->resolution);
+	*temp = lm75_reg_to_mc(_temp, data->resolution);
 
 	return 0;
 }
···
 			 char *buf)
 {
 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
-	struct lm75_data *data = lm75_update_device(dev);
+	struct lm75_data *data = dev_get_drvdata(dev);
+	unsigned int temp = 0;
+	int err;
 
-	if (IS_ERR(data))
-		return PTR_ERR(data);
+	err = regmap_read(data->regmap, attr->index, &temp);
+	if (err < 0)
+		return err;
 
-	return sprintf(buf, "%ld\n", lm75_reg_to_mc(data->temp[attr->index],
-						    data->resolution));
+	return sprintf(buf, "%ld\n", lm75_reg_to_mc(temp, data->resolution));
 }
 
 static ssize_t set_temp(struct device *dev, struct device_attribute *da,
···
 {
 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
 	struct lm75_data *data = dev_get_drvdata(dev);
-	struct i2c_client *client = data->client;
-	int nr = attr->index;
 	long temp;
 	int error;
 	u8 resolution;
···
 	else
 		resolution = data->resolution;
 
-	mutex_lock(&data->update_lock);
 	temp = clamp_val(temp, LM75_TEMP_MIN, LM75_TEMP_MAX);
-	data->temp[nr] = DIV_ROUND_CLOSEST(temp  << (resolution - 8),
-					   1000) << (16 - resolution);
-	lm75_write_value(client, LM75_REG_TEMP[nr], data->temp[nr]);
-	mutex_unlock(&data->update_lock);
+	temp = DIV_ROUND_CLOSEST(temp  << (resolution - 8),
+				 1000) << (16 - resolution);
+	error = regmap_write(data->regmap, attr->index, temp);
+	if (error < 0)
+		return error;
+
 	return count;
 }
 
+static ssize_t show_update_interval(struct device *dev,
+				    struct device_attribute *da, char *buf)
+{
+	struct lm75_data *data = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%u\n", data->sample_time);
+}
+
 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,
-			show_temp, set_temp, 1);
+			show_temp, set_temp, LM75_REG_MAX);
 static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO,
-			show_temp, set_temp, 2);
-static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
+			show_temp, set_temp, LM75_REG_HYST);
+static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, LM75_REG_TEMP);
+static DEVICE_ATTR(update_interval, S_IRUGO, show_update_interval, NULL);
 
 static struct attribute *lm75_attrs[] = {
 	&sensor_dev_attr_temp1_input.dev_attr.attr,
 	&sensor_dev_attr_temp1_max.dev_attr.attr,
 	&sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
+	&dev_attr_update_interval.attr,
 
 	NULL
 };
···
 
 /* device probe and removal */
 
+static bool lm75_is_writeable_reg(struct device *dev, unsigned int reg)
+{
+	return reg != LM75_REG_TEMP;
+}
+
+static bool lm75_is_volatile_reg(struct device *dev, unsigned int reg)
+{
+	return reg == LM75_REG_TEMP;
+}
+
+static const struct regmap_config lm75_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 16,
+	.max_register = LM75_REG_MAX,
+	.writeable_reg = lm75_is_writeable_reg,
+	.volatile_reg = lm75_is_volatile_reg,
+	.val_format_endian = REGMAP_ENDIAN_BIG,
+	.cache_type = REGCACHE_RBTREE,
+	.use_single_rw = true,
+};
+
+static void lm75_remove(void *data)
+{
+	struct lm75_data *lm75 = data;
+	struct i2c_client *client = lm75->client;
+
+	i2c_smbus_write_byte_data(client, LM75_REG_CONF, lm75->orig_conf);
+}
+
 static int
 lm75_probe(struct i2c_client *client, const struct i2c_device_id *id)
 {
 	struct device *dev = &client->dev;
+	struct device *hwmon_dev;
 	struct lm75_data *data;
 	int status;
 	u8 set_mask, clr_mask;
···
 		return -ENOMEM;
 
 	data->client = client;
-	i2c_set_clientdata(client, data);
-	mutex_init(&data->update_lock);
+
+	data->regmap = devm_regmap_init_i2c(client, &lm75_regmap_config);
+	if (IS_ERR(data->regmap))
+		return PTR_ERR(data->regmap);
 
 	/* Set to LM75 resolution (9 bits, 1/2 degree C) and range.
 	 * Then tweak to be more precise when appropriate.
···
 	case adt75:
 		clr_mask |= 1 << 5;		/* not one-shot mode */
 		data->resolution = 12;
-		data->sample_time = HZ / 8;
+		data->sample_time = MSEC_PER_SEC / 8;
 		break;
 	case ds1775:
 	case ds75:
···
 		clr_mask |= 3 << 5;
 		set_mask |= 2 << 5;		/* 11-bit mode */
 		data->resolution = 11;
-		data->sample_time = HZ;
+		data->sample_time = MSEC_PER_SEC;
 		break;
 	case ds7505:
 		set_mask |= 3 << 5;		/* 12-bit mode */
 		data->resolution = 12;
-		data->sample_time = HZ / 4;
+		data->sample_time = MSEC_PER_SEC / 4;
 		break;
 	case g751:
 	case lm75:
 	case lm75a:
 		data->resolution = 9;
-		data->sample_time = HZ / 2;
+		data->sample_time = MSEC_PER_SEC / 2;
 		break;
 	case lm75b:
 		data->resolution = 11;
-		data->sample_time = HZ / 4;
+		data->sample_time = MSEC_PER_SEC / 4;
 		break;
 	case max6625:
 		data->resolution = 9;
-		data->sample_time = HZ / 4;
+		data->sample_time = MSEC_PER_SEC / 4;
 		break;
 	case max6626:
 		data->resolution = 12;
 		data->resolution_limits = 9;
-		data->sample_time = HZ / 4;
+		data->sample_time = MSEC_PER_SEC / 4;
 		break;
 	case tcn75:
 		data->resolution = 9;
-		data->sample_time = HZ / 8;
+		data->sample_time = MSEC_PER_SEC / 8;
 		break;
 	case mcp980x:
 		data->resolution_limits = 9;
···
 	case tmp101:
 		set_mask |= 3 << 5;		/* 12-bit mode */
 		data->resolution = 12;
-		data->sample_time = HZ;
+		data->sample_time = MSEC_PER_SEC;
 		clr_mask |= 1 << 7;		/* not one-shot mode */
 		break;
 	case tmp112:
 		set_mask |= 3 << 5;		/* 12-bit mode */
 		clr_mask |= 1 << 7;		/* not one-shot mode */
 		data->resolution = 12;
-		data->sample_time = HZ / 4;
+		data->sample_time = MSEC_PER_SEC / 4;
 		break;
 	case tmp105:
 	case tmp175:
···
 		set_mask |= 3 << 5;		/* 12-bit mode */
 		clr_mask |= 1 << 7;		/* not one-shot mode */
 		data->resolution = 12;
-		data->sample_time = HZ / 2;
+		data->sample_time = MSEC_PER_SEC / 2;
 		break;
 	case tmp75c:
 		clr_mask |= 1 << 5;		/* not one-shot mode */
 		data->resolution = 12;
-		data->sample_time = HZ / 4;
+		data->sample_time = MSEC_PER_SEC / 4;
 		break;
 	}
 
 	/* configure as specified */
-	status = lm75_read_value(client, LM75_REG_CONF);
+	status = i2c_smbus_read_byte_data(client, LM75_REG_CONF);
 	if (status < 0) {
 		dev_dbg(dev, "Can't read config? %d\n", status);
 		return status;
···
 	new = status & ~clr_mask;
 	new |= set_mask;
 	if (status != new)
-		lm75_write_value(client, LM75_REG_CONF, new);
+		i2c_smbus_write_byte_data(client, LM75_REG_CONF, new);
+
+	devm_add_action(dev, lm75_remove, data);
+
 	dev_dbg(dev, "Config %02x\n", new);
 
-	data->hwmon_dev = hwmon_device_register_with_groups(dev, client->name,
-							    data, lm75_groups);
-	if (IS_ERR(data->hwmon_dev))
-		return PTR_ERR(data->hwmon_dev);
+	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
+							   data, lm75_groups);
+	if (IS_ERR(hwmon_dev))
+		return PTR_ERR(hwmon_dev);
 
-	devm_thermal_zone_of_sensor_register(data->hwmon_dev, 0,
-					     data->hwmon_dev,
+	devm_thermal_zone_of_sensor_register(hwmon_dev, 0,
+					     hwmon_dev,
 					     &lm75_of_thermal_ops);
 
-	dev_info(dev, "%s: sensor '%s'\n",
-		 dev_name(data->hwmon_dev), client->name);
+	dev_info(dev, "%s: sensor '%s'\n", dev_name(hwmon_dev), client->name);
 
-	return 0;
-}
-
-static int lm75_remove(struct i2c_client *client)
-{
-	struct lm75_data *data = i2c_get_clientdata(client);
-
-	hwmon_device_unregister(data->hwmon_dev);
-	lm75_write_value(client, LM75_REG_CONF, data->orig_conf);
 	return 0;
 }
 
···
 {
 	int status;
 	struct i2c_client *client = to_i2c_client(dev);
-	status = lm75_read_value(client, LM75_REG_CONF);
+	status = i2c_smbus_read_byte_data(client, LM75_REG_CONF);
 	if (status < 0) {
 		dev_dbg(&client->dev, "Can't read config? %d\n", status);
 		return status;
 	}
 	status = status | LM75_SHUTDOWN;
-	lm75_write_value(client, LM75_REG_CONF, status);
+	i2c_smbus_write_byte_data(client, LM75_REG_CONF, status);
 	return 0;
 }
 
···
 {
 	int status;
 	struct i2c_client *client = to_i2c_client(dev);
-	status = lm75_read_value(client, LM75_REG_CONF);
+	status = i2c_smbus_read_byte_data(client, LM75_REG_CONF);
 	if (status < 0) {
 		dev_dbg(&client->dev, "Can't read config? %d\n", status);
 		return status;
 	}
 	status = status & ~LM75_SHUTDOWN;
-	lm75_write_value(client, LM75_REG_CONF, status);
+	i2c_smbus_write_byte_data(client, LM75_REG_CONF, status);
 	return 0;
 }
 
···
 		.pm	= LM75_DEV_PM_OPS,
 	},
 	.probe		= lm75_probe,
-	.remove		= lm75_remove,
 	.id_table	= lm75_ids,
 	.detect		= lm75_detect,
 	.address_list	= normal_i2c,
 };
-
-/*-----------------------------------------------------------------------*/
-
-/* register access */
-
-/*
- * All registers are word-sized, except for the configuration register.
- * LM75 uses a high-byte first convention, which is exactly opposite to
- * the SMBus standard.
- */
-static int lm75_read_value(struct i2c_client *client, u8 reg)
-{
-	if (reg == LM75_REG_CONF)
-		return i2c_smbus_read_byte_data(client, reg);
-	else
-		return i2c_smbus_read_word_swapped(client, reg);
-}
-
-static int lm75_write_value(struct i2c_client *client, u8 reg, u16 value)
-{
-	if (reg == LM75_REG_CONF)
-		return i2c_smbus_write_byte_data(client, reg, value);
-	else
-		return i2c_smbus_write_word_swapped(client, reg, value);
-}
-
-static struct lm75_data *lm75_update_device(struct device *dev)
-{
-	struct lm75_data *data = dev_get_drvdata(dev);
-	struct i2c_client *client = data->client;
-	struct lm75_data *ret = data;
-
-	mutex_lock(&data->update_lock);
-
-	if (time_after(jiffies, data->last_updated + data->sample_time)
-	    || !data->valid) {
-		int i;
-		dev_dbg(&client->dev, "Starting lm75 update\n");
-
-		for (i = 0; i < ARRAY_SIZE(data->temp); i++) {
-			int status;
-
-			status = lm75_read_value(client, LM75_REG_TEMP[i]);
-			if (unlikely(status < 0)) {
-				dev_dbg(dev,
-					"LM75: Failed to read value: reg %d, error %d\n",
-					LM75_REG_TEMP[i], status);
-				ret = ERR_PTR(status);
-				data->valid = 0;
-				goto abort;
-			}
-			data->temp[i] = status;
-		}
-		data->last_updated = jiffies;
-		data->valid = 1;
-	}
-
-abort:
-	mutex_unlock(&data->update_lock);
-	return ret;
-}
 
 module_i2c_driver(lm75_driver);
 

drivers/hwmon/lm90.c

···
 
 #define SA56004_REG_R_LOCAL_TEMPL 0x22
 
-#define LM90_DEF_CONVRATE_RVAL	6	/* Def conversion rate register value */
 #define LM90_MAX_CONVRATE_MS	16000	/* Maximum conversion rate in ms */
 
 /* TMP451 registers */
···
 
 struct lm90_data {
 	struct i2c_client *client;
-	struct device *hwmon_dev;
 	const struct attribute_group *groups[6];
 	struct mutex update_lock;
-	struct regulator *regulator;
-	char valid; /* zero until following fields are valid */
+	bool valid;		/* true if register values are valid */
 	unsigned long last_updated; /* in jiffies */
 	int kind;
 	u32 flags;
···
  * because we don't want the address pointer to change between the write
  * byte and the read byte transactions.
  */
-static int lm90_read_reg(struct i2c_client *client, u8 reg, u8 *value)
+static int lm90_read_reg(struct i2c_client *client, u8 reg)
 {
 	int err;
 
···
 	} else
 		err = i2c_smbus_read_byte_data(client, reg);
 
-	if (err < 0) {
-		dev_warn(&client->dev, "Register %#02x read failed (%d)\n",
-			 reg, err);
-		return err;
-	}
-	*value = err;
-
-	return 0;
+	return err;
 }
 
-static int lm90_read16(struct i2c_client *client, u8 regh, u8 regl, u16 *value)
+static int lm90_read16(struct i2c_client *client, u8 regh, u8 regl)
 {
-	int err;
-	u8 oldh, newh, l;
+	int oldh, newh, l;
 
 	/*
 	 * There is a trick here. We have to read two registers to have the
···
 	 * we have to read the low byte again, and now we believe we have a
 	 * correct reading.
 	 */
-	if ((err = lm90_read_reg(client, regh, &oldh))
-	 || (err = lm90_read_reg(client, regl, &l))
-	 || (err = lm90_read_reg(client, regh, &newh)))
-		return err;
+	oldh = lm90_read_reg(client, regh);
+	if (oldh < 0)
+		return oldh;
+	l = lm90_read_reg(client, regl);
+	if (l < 0)
+		return l;
+	newh = lm90_read_reg(client, regh);
+	if (newh < 0)
+		return newh;
 	if (oldh != newh) {
-		err = lm90_read_reg(client, regl, &l);
-		if (err)
-			return err;
+		l = lm90_read_reg(client, regl);
+		if (l < 0)
+			return l;
 	}
-	*value = (newh << 8) | l;
-
-	return 0;
+	return (newh << 8) | l;
 }
 
 /*
···
  * various registers have different meanings as a result of selecting a
  * non-default remote channel.
  */
-static inline void lm90_select_remote_channel(struct i2c_client *client,
-					      struct lm90_data *data,
-					      int channel)
+static inline int lm90_select_remote_channel(struct i2c_client *client,
+					     struct lm90_data *data,
+					     int channel)
 {
-	u8 config;
+	int config;
 
 	if (data->kind == max6696) {
-		lm90_read_reg(client, LM90_REG_R_CONFIG1, &config);
+		config = lm90_read_reg(client, LM90_REG_R_CONFIG1);
+		if (config < 0)
+			return config;
 		config &= ~0x08;
 		if (channel)
 			config |= 0x08;
 		i2c_smbus_write_byte_data(client, LM90_REG_W_CONFIG1,
 					  config);
 	}
+	return 0;
 }
 
 /*
···
 	data->update_interval = DIV_ROUND_CLOSEST(update_interval, 64);
 }
 
+static int lm90_update_limits(struct device *dev)
+{
+	struct lm90_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
+	int val;
+
+	val = lm90_read_reg(client, LM90_REG_R_LOCAL_CRIT);
+	if (val < 0)
+		return val;
+	data->temp8[LOCAL_CRIT] = val;
+
+	val = lm90_read_reg(client, LM90_REG_R_REMOTE_CRIT);
+	if (val < 0)
+		return val;
+	data->temp8[REMOTE_CRIT] = val;
+
+	val = lm90_read_reg(client, LM90_REG_R_TCRIT_HYST);
+	if (val < 0)
+		return val;
+	data->temp_hyst = val;
+
+	lm90_read_reg(client, LM90_REG_R_REMOTE_LOWH);
+	if (val < 0)
+		return val;
+	data->temp11[REMOTE_LOW] = val << 8;
+
+	if (data->flags & LM90_HAVE_REM_LIMIT_EXT) {
+		val = lm90_read_reg(client, LM90_REG_R_REMOTE_LOWL);
+		if (val < 0)
+			return val;
+		data->temp11[REMOTE_LOW] |= val;
+	}
+
+	val = lm90_read_reg(client, LM90_REG_R_REMOTE_HIGHH);
+	if (val < 0)
+		return val;
+	data->temp11[REMOTE_HIGH] = val << 8;
+
+	if (data->flags & LM90_HAVE_REM_LIMIT_EXT) {
+		val = lm90_read_reg(client, LM90_REG_R_REMOTE_HIGHL);
+		if (val < 0)
+			return val;
+		data->temp11[REMOTE_HIGH] |= val;
+	}
+
+	if (data->flags & LM90_HAVE_OFFSET) {
+		val = lm90_read16(client, LM90_REG_R_REMOTE_OFFSH,
+				  LM90_REG_R_REMOTE_OFFSL);
+		if (val < 0)
+			return val;
+		data->temp11[REMOTE_OFFSET] = val;
+	}
+
+	if (data->flags & LM90_HAVE_EMERGENCY) {
+		val = lm90_read_reg(client, MAX6659_REG_R_LOCAL_EMERG);
+		if (val < 0)
+			return val;
+		data->temp8[LOCAL_EMERG] = val;
+
+		val = lm90_read_reg(client, MAX6659_REG_R_REMOTE_EMERG);
+		if (val < 0)
+			return val;
+		data->temp8[REMOTE_EMERG] = val;
+	}
+
+	if (data->kind == max6696) {
+		val = lm90_select_remote_channel(client, data, 1);
+		if (val < 0)
+			return val;
+
+		val = lm90_read_reg(client, LM90_REG_R_REMOTE_CRIT);
+		if (val < 0)
+			return val;
+		data->temp8[REMOTE2_CRIT] = val;
+
+		val = lm90_read_reg(client, MAX6659_REG_R_REMOTE_EMERG);
+		if (val < 0)
+			return val;
+		data->temp8[REMOTE2_EMERG] = val;
+
+		val = lm90_read_reg(client, LM90_REG_R_REMOTE_LOWH);
+		if (val < 0)
+			return val;
+		data->temp11[REMOTE2_LOW] = val << 8;
+
+		val = lm90_read_reg(client, LM90_REG_R_REMOTE_HIGHH);
+		if (val < 0)
+			return val;
+		data->temp11[REMOTE2_HIGH] = val << 8;
+
+		lm90_select_remote_channel(client, data, 0);
+	}
+
+	return 0;
+}
+
 static struct lm90_data *lm90_update_device(struct device *dev)
 {
 	struct lm90_data *data = dev_get_drvdata(dev);
 	struct i2c_client *client = data->client;
 	unsigned long next_update;
+	int val = 0;
 
 	mutex_lock(&data->update_lock);
+
+	if (!data->valid) {
+		val = lm90_update_limits(dev);
+		if (val < 0)
+			goto error;
+	}
 
 	next_update = data->last_updated +
 		      msecs_to_jiffies(data->update_interval);
 	if (time_after(jiffies, next_update) || !data->valid) {
-		u8 h, l;
-		u8 alarms;
-
 		dev_dbg(&client->dev, "Updating lm90 data.\n");
-		lm90_read_reg(client, LM90_REG_R_LOCAL_LOW,
-			      &data->temp8[LOCAL_LOW]);
-		lm90_read_reg(client, LM90_REG_R_LOCAL_HIGH,
-			      &data->temp8[LOCAL_HIGH]);
-		lm90_read_reg(client, LM90_REG_R_LOCAL_CRIT,
-			      &data->temp8[LOCAL_CRIT]);
-		lm90_read_reg(client, LM90_REG_R_REMOTE_CRIT,
-			      &data->temp8[REMOTE_CRIT]);
-		lm90_read_reg(client, LM90_REG_R_TCRIT_HYST, &data->temp_hyst);
+
+		data->valid = false;
+
+		val = lm90_read_reg(client, LM90_REG_R_LOCAL_LOW);
+		if (val < 0)
+			goto error;
+		data->temp8[LOCAL_LOW] = val;
+
+		val = lm90_read_reg(client, LM90_REG_R_LOCAL_HIGH);
+		if (val < 0)
+			goto error;
+		data->temp8[LOCAL_HIGH] = val;
 
 		if (data->reg_local_ext) {
-			lm90_read16(client, LM90_REG_R_LOCAL_TEMP,
-				    data->reg_local_ext,
-				    &data->temp11[LOCAL_TEMP]);
+			val = lm90_read16(client, LM90_REG_R_LOCAL_TEMP,
+					  data->reg_local_ext);
+			if (val < 0)
+				goto error;
+			data->temp11[LOCAL_TEMP] = val;
 		} else {
-			if (lm90_read_reg(client, LM90_REG_R_LOCAL_TEMP,
-					  &h) == 0)
-				data->temp11[LOCAL_TEMP] = h << 8;
+			val = lm90_read_reg(client, LM90_REG_R_LOCAL_TEMP);
+			if (val < 0)
+				goto error;
+			data->temp11[LOCAL_TEMP] = val << 8;
 		}
-		lm90_read16(client, LM90_REG_R_REMOTE_TEMPH,
-			    LM90_REG_R_REMOTE_TEMPL,
-			    &data->temp11[REMOTE_TEMP]);
+		val = lm90_read16(client, LM90_REG_R_REMOTE_TEMPH,
+				  LM90_REG_R_REMOTE_TEMPL);
+		if (val < 0)
+			goto error;
+		data->temp11[REMOTE_TEMP] = val;
 
-		if (lm90_read_reg(client, LM90_REG_R_REMOTE_LOWH, &h) == 0) {
-			data->temp11[REMOTE_LOW] = h << 8;
-			if ((data->flags & LM90_HAVE_REM_LIMIT_EXT)
-			 && lm90_read_reg(client, LM90_REG_R_REMOTE_LOWL,
-					  &l) == 0)
-				data->temp11[REMOTE_LOW] |= l;
-		}
-		if (lm90_read_reg(client, LM90_REG_R_REMOTE_HIGHH, &h) == 0) {
-			data->temp11[REMOTE_HIGH] = h << 8;
-			if ((data->flags & LM90_HAVE_REM_LIMIT_EXT)
-			 && lm90_read_reg(client, LM90_REG_R_REMOTE_HIGHL,
-					  &l) == 0)
-				data->temp11[REMOTE_HIGH] |= l;
-		}
-
-		if (data->flags & LM90_HAVE_OFFSET) {
-			if (lm90_read_reg(client, LM90_REG_R_REMOTE_OFFSH,
-					  &h) == 0
-			 && lm90_read_reg(client, LM90_REG_R_REMOTE_OFFSL,
-					  &l) == 0)
-				data->temp11[REMOTE_OFFSET] = (h << 8) | l;
-		}
-		if (data->flags & LM90_HAVE_EMERGENCY) {
-			lm90_read_reg(client, MAX6659_REG_R_LOCAL_EMERG,
-				      &data->temp8[LOCAL_EMERG]);
-			lm90_read_reg(client, MAX6659_REG_R_REMOTE_EMERG,
-				      &data->temp8[REMOTE_EMERG]);
-		}
-		lm90_read_reg(client, LM90_REG_R_STATUS, &alarms);
-		data->alarms = alarms;	/* save as 16 bit value */
+		val = lm90_read_reg(client, LM90_REG_R_STATUS);
+		if (val < 0)
+			goto error;
+		data->alarms = val;	/* lower 8 bit of alarms */
 
 		if (data->kind == max6696) {
-			lm90_select_remote_channel(client, data, 1);
-			lm90_read_reg(client, LM90_REG_R_REMOTE_CRIT,
-				      &data->temp8[REMOTE2_CRIT]);
-			lm90_read_reg(client, MAX6659_REG_R_REMOTE_EMERG,
-				      &data->temp8[REMOTE2_EMERG]);
-			lm90_read16(client, LM90_REG_R_REMOTE_TEMPH,
-				    LM90_REG_R_REMOTE_TEMPL,
-				    &data->temp11[REMOTE2_TEMP]);
-			if (!lm90_read_reg(client, LM90_REG_R_REMOTE_LOWH, &h))
-				data->temp11[REMOTE2_LOW] = h << 8;
-			if (!lm90_read_reg(client, LM90_REG_R_REMOTE_HIGHH, &h))
-				data->temp11[REMOTE2_HIGH] = h << 8;
+			val = lm90_select_remote_channel(client, data, 1);
+			if (val < 0)
+				goto error;
+
+			val = lm90_read16(client, LM90_REG_R_REMOTE_TEMPH,
+					  LM90_REG_R_REMOTE_TEMPL);
+			if (val < 0)
+				goto error;
+			data->temp11[REMOTE2_TEMP] = val;
+
 			lm90_select_remote_channel(client, data, 0);
 
-			if (!lm90_read_reg(client, MAX6696_REG_R_STATUS2,
-					   &alarms))
-				data->alarms |= alarms << 8;
+			val = lm90_read_reg(client, MAX6696_REG_R_STATUS2);
+			if (val < 0)
+				goto error;
+			data->alarms |= val << 8;
 		}
 
 		/*
 		 * Re-enable ALERT# output if it was originally enabled and
 		 * relevant alarms are all clear
 		 */
-		if ((data->config_orig & 0x80) == 0
-		 && (data->alarms & data->alert_alarms) == 0) {
-			u8 config;
+		if (!(data->config_orig & 0x80) &&
+		    !(data->alarms & data->alert_alarms)) {
+			val = lm90_read_reg(client, LM90_REG_R_CONFIG1);
+			if (val < 0)
+				goto error;
 
-			lm90_read_reg(client, LM90_REG_R_CONFIG1, &config);
-			if (config & 0x80) {
+			if (val & 0x80) {
 				dev_dbg(&client->dev, "Re-enabling ALERT#\n");
 				i2c_smbus_write_byte_data(client,
 							  LM90_REG_W_CONFIG1,
-							  config & ~0x80);
+							  val & ~0x80);
 			}
 		}
 
 		data->last_updated = jiffies;
-		data->valid = 1;
+		data->valid = true;
 	}
 
+error:
 	mutex_unlock(&data->update_lock);
+
+	if (val < 0)
+		return ERR_PTR(val);
 
 	return data;
 }
···
 {
 	if (data->flags & LM90_FLAG_ADT7461_EXT)
 		return (val - 64) * 1000;
-	else
-		return temp_from_s8(val);
+	return temp_from_s8(val);
 }
 
 static inline int temp_from_u16_adt7461(struct lm90_data *data, u16 val)
 {
 	if (data->flags & LM90_FLAG_ADT7461_EXT)
 		return (val - 0x4000) / 64 * 250;
-	else
-		return temp_from_s16(val);
+	return temp_from_s16(val);
 }
 
 static u8 temp_to_u8_adt7461(struct lm90_data *data, long val)
···
 		if (val >= 191000)
 			return 0xFF;
 		return (val + 500 + 64000) / 1000;
-	} else {
-		if (val <= 0)
-			return 0;
-		if (val >= 127000)
-			return 127;
-		return (val + 500) / 1000;
 	}
+	if (val <= 0)
+		return 0;
+	if (val >= 127000)
+		return 127;
+	return (val + 500) / 1000;
 }
 
 static u16 temp_to_u16_adt7461(struct lm90_data *data, long val)
···
 		if (val >= 191750)
 			return 0xFFC0;
 		return (val + 64000 + 125) / 250 * 64;
-	} else {
-		if (val <= 0)
-			return 0;
-		if (val >= 127750)
-			return 0x7FC0;
-		return (val + 125) / 250 * 64;
 	}
+	if (val <= 0)
+		return 0;
+	if (val >= 127750)
+		return 0x7FC0;
+	return (val + 125) / 250 * 64;
 }
 
 /*
···
 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 	struct lm90_data *data = lm90_update_device(dev);
 	int temp;
+
+	if (IS_ERR(data))
+		return PTR_ERR(data);
 
 	if (data->kind == adt7461 || data->kind == tmp451)
 		temp = temp_from_u8_adt7461(data, data->temp8[attr->index]);
···
 	struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(devattr);
 	struct lm90_data *data = lm90_update_device(dev);
 	int temp;
+
+	if (IS_ERR(data))
+		return PTR_ERR(data);
 
 	if (data->kind == adt7461 || data->kind == tmp451)
 		temp = temp_from_u16_adt7461(data, data->temp11[attr->index]);
···
 	struct lm90_data *data = lm90_update_device(dev);
 	int temp;
 
+	if (IS_ERR(data))
+		return PTR_ERR(data);
+
 	if (data->kind == adt7461 || data->kind == tmp451)
 		temp = temp_from_u8_adt7461(data, data->temp8[attr->index]);
 	else if (data->kind == max6646)
···
 			   char *buf)
 {
 	struct lm90_data *data = lm90_update_device(dev);
+
+	if (IS_ERR(data))
+		return PTR_ERR(data);
+
 	return sprintf(buf, "%d\n", data->alarms);
 }
 
···
 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 	struct lm90_data *data = lm90_update_device(dev);
 	int bitnr = attr->index;
+
+	if (IS_ERR(data))
+		return PTR_ERR(data);
 
 	return sprintf(buf, "%d\n", (data->alarms >> bitnr) & 1);
 }
···
 	return 0;
 }
 
-static void lm90_restore_conf(struct i2c_client *client, struct lm90_data *data)
+static void lm90_restore_conf(void *_data)
 {
+	struct lm90_data *data = _data;
+	struct i2c_client *client = data->client;
+
 	/* Restore initial configuration */
 	i2c_smbus_write_byte_data(client, LM90_REG_W_CONVRATE,
 				  data->convrate_orig);
···
 				  data->config_orig);
 }
 
-static void lm90_init_client(struct i2c_client *client, struct lm90_data *data)
+static int lm90_init_client(struct i2c_client *client, struct lm90_data *data)
 {
-	u8 config, convrate;
+	int config, convrate;
 
-	if (lm90_read_reg(client, LM90_REG_R_CONVRATE, &convrate) < 0) {
-		dev_warn(&client->dev, "Failed to read convrate register!\n");
-		convrate = LM90_DEF_CONVRATE_RVAL;
-	}
+	convrate = lm90_read_reg(client, LM90_REG_R_CONVRATE);
+	if (convrate < 0)
+		return convrate;
 	data->convrate_orig = convrate;
 
 	/*
 	 * Start the conversions.
 	 */
 	lm90_set_convrate(client, data, 500);	/* 500ms; 2Hz conversion rate */
-	if (lm90_read_reg(client, LM90_REG_R_CONFIG1, &config) < 0) {
-		dev_warn(&client->dev, "Initialization failed!\n");
-		return;
-	}
+	config = lm90_read_reg(client, LM90_REG_R_CONFIG1);
+	if (config < 0)
+		return config;
 	data->config_orig = config;
 
 	/* Check Temperature Range Select */
···
 	config &= 0xBF;	/* run */
 	if (config != data->config_orig) /* Only write if changed */
 		i2c_smbus_write_byte_data(client, LM90_REG_W_CONFIG1, config);
+
+	devm_add_action(&client->dev, lm90_restore_conf, data);
+
+	return 0;
 }
 
 static bool lm90_is_tripped(struct i2c_client *client, u16 *status)
 {
 	struct lm90_data *data = i2c_get_clientdata(client);
-	u8 st, st2 = 0;
+	int st, st2 = 0;
 
-	lm90_read_reg(client, LM90_REG_R_STATUS, &st);
+	st = lm90_read_reg(client, LM90_REG_R_STATUS);
+	if (st < 0)
+		return false;
 
-	if (data->kind == max6696)
-		lm90_read_reg(client, MAX6696_REG_R_STATUS2, &st2);
+	if (data->kind == max6696) {
+		st2 = lm90_read_reg(client, MAX6696_REG_R_STATUS2);
+		if (st2 < 0)
+			return false;
+	}
 
 	*status = st | (st2 << 8);
 
···
 		return IRQ_NONE;
 }
 
+static void lm90_remove_pec(void *dev)
+{
+	device_remove_file(dev, &dev_attr_pec);
+}
+
+static void lm90_regulator_disable(void *regulator)
+{
+	regulator_disable(regulator);
+}
+
 static int lm90_probe(struct i2c_client *client,
 		      const struct i2c_device_id *id)
 {
···
 	struct i2c_adapter *adapter = to_i2c_adapter(dev->parent);
 	struct lm90_data *data;
 	struct regulator *regulator;
+	struct device *hwmon_dev;
 	int groups = 0;
 	int err;
 
···
 		return err;
 	}
 
+	devm_add_action(dev, lm90_regulator_disable, regulator);
+
 	data = devm_kzalloc(dev, sizeof(struct lm90_data), GFP_KERNEL);
 	if (!data)
 		return -ENOMEM;
···
 	data->client = client;
 	i2c_set_clientdata(client, data);
 	mutex_init(&data->update_lock);
-
-	data->regulator = regulator;
 
 	/* Set the device type */
 	data->kind = id->driver_data;
···
 	data->max_convrate = lm90_params[data->kind].max_convrate;
 
 	/* Initialize the LM90 chip */
-	lm90_init_client(client, data);
+	err = lm90_init_client(client, data);
+	if (err < 0) {
+		dev_err(dev, "Failed to initialize device\n");
+		return err;
+	}
 
 	/* Register sysfs hooks */
 	data->groups[groups++] = &lm90_group;
···
 	if (client->flags & I2C_CLIENT_PEC) {
 		err = device_create_file(dev, &dev_attr_pec);
 		if (err)
-			goto exit_restore;
+			return err;
+		devm_add_action(dev, lm90_remove_pec, dev);
 	}
 
-	data->hwmon_dev = hwmon_device_register_with_groups(dev, client->name,
-							    data, data->groups);
-	if (IS_ERR(data->hwmon_dev)) {
-		err = PTR_ERR(data->hwmon_dev);
-		goto exit_remove_pec;
-	}
+	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
+							   data, data->groups);
+	if (IS_ERR(hwmon_dev))
+		return PTR_ERR(hwmon_dev);
 
 	if (client->irq) {
 		dev_dbg(dev, "IRQ: %d\n", client->irq);
···
 						"lm90", client);
 		if (err < 0) {
 			dev_err(dev, "cannot request IRQ %d\n", client->irq);
-			goto exit_unregister;
+			return err;
 		}
 	}
-
-	return 0;
-
-exit_unregister:
-	hwmon_device_unregister(data->hwmon_dev);
-exit_remove_pec:
-	device_remove_file(dev, &dev_attr_pec);
-exit_restore:
-	lm90_restore_conf(client, data);
-	regulator_disable(data->regulator);
-
-	return err;
-}
-
-static int lm90_remove(struct i2c_client *client)
-{
-	struct lm90_data *data = i2c_get_clientdata(client);
-
-	hwmon_device_unregister(data->hwmon_dev);
-	device_remove_file(&client->dev, &dev_attr_pec);
-	lm90_restore_conf(client, data);
-	regulator_disable(data->regulator);
 
 	return 0;
 }
···
 		 */
 		struct lm90_data *data = i2c_get_clientdata(client);
 
-		if ((data->flags & LM90_HAVE_BROKEN_ALERT)
-		 && (alarms & data->alert_alarms)) {
-			u8 config;
+		if ((data->flags & LM90_HAVE_BROKEN_ALERT) &&
+		    (alarms & data->alert_alarms)) {
+			int config;
+
 			dev_dbg(&client->dev, "Disabling ALERT#\n");
-			lm90_read_reg(client, LM90_REG_R_CONFIG1, &config);
-			i2c_smbus_write_byte_data(client, LM90_REG_W_CONFIG1,
-						  config | 0x80);
+			config = lm90_read_reg(client, LM90_REG_R_CONFIG1);
+			if (config >= 0)
+				i2c_smbus_write_byte_data(client,
+							  LM90_REG_W_CONFIG1,
+							  config | 0x80);
 		}
 	} else {
 		dev_info(&client->dev, "Everything OK\n");
···
 		.name	= "lm90",
 	},
 	.probe		= lm90_probe,
-	.remove		= lm90_remove,
 	.alert		= lm90_alert,
 	.id_table	= lm90_id,
 	.detect		= lm90_detect,

drivers/hwmon/sht3x.c

···
+/* Sensirion SHT3x-DIS humidity and temperature sensor driver.
+ * The SHT3x comes in many different versions, this driver is for the
+ * I2C version only.
+ *
+ * Copyright (C) 2016 Sensirion AG, Switzerland
+ * Author: David Frey <[e-mail]>
+ * Author: Pascal Sachs <[e-mail]>
+ *
+ * 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 <asm/page.h>
+#include <linux/crc8.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/jiffies.h>
+#include <linux/platform_data/sht3x.h>
+
+/* commands (high precision mode) */
+static const unsigned char sht3x_cmd_measure_blocking_hpm[]    = { 0x2c, 0x06 };
+static const unsigned char sht3x_cmd_measure_nonblocking_hpm[] = { 0x24, 0x00 };
+
+/* commands (low power mode) */
+static const unsigned char sht3x_cmd_measure_blocking_lpm[]    = { 0x2c, 0x10 };
+static const unsigned char sht3x_cmd_measure_nonblocking_lpm[] = { 0x24, 0x16 };
+
+/* commands for periodic mode */
+static const unsigned char sht3x_cmd_measure_periodic_mode[]   = { 0xe0, 0x00 };
+static const unsigned char sht3x_cmd_break[]                   = { 0x30, 0x93 };
+
+/* commands for heater control */
+static const unsigned char sht3x_cmd_heater_on[]               = { 0x30, 0x6d };
+static const unsigned char sht3x_cmd_heater_off[]              = { 0x30, 0x66 };
+
+/* other commands */
+static const unsigned char sht3x_cmd_read_status_reg[]         = { 0xf3, 0x2d };
+static const unsigned char sht3x_cmd_clear_status_reg[]        = { 0x30, 0x41 };
+
+/* delays for non-blocking i2c commands, both in us */
+#define SHT3X_NONBLOCKING_WAIT_TIME_HPM  15000
+#define SHT3X_NONBLOCKING_WAIT_TIME_LPM   4000
+
+#define SHT3X_WORD_LEN         2
+#define SHT3X_CMD_LENGTH       2
+#define SHT3X_CRC8_LEN         1
+#define SHT3X_RESPONSE_LENGTH  6
+#define SHT3X_CRC8_POLYNOMIAL  0x31
+#define SHT3X_CRC8_INIT        0xFF
+#define SHT3X_MIN_TEMPERATURE  -45000
+#define SHT3X_MAX_TEMPERATURE  130000
+#define SHT3X_MIN_HUMIDITY     0
+#define SHT3X_MAX_HUMIDITY     100000
+
+enum sht3x_chips {
+	sht3x,
+	sts3x,
+};
+
+enum sht3x_limits {
+	limit_max = 0,
+	limit_max_hyst,
+	limit_min,
+	limit_min_hyst,
+};
+
+DECLARE_CRC8_TABLE(sht3x_crc8_table);
+
+/* periodic measure commands (high precision mode) */
+static const char periodic_measure_commands_hpm[][SHT3X_CMD_LENGTH] = {
+	/* 0.5 measurements per second */
+	{0x20, 0x32},
+	/* 1 measurements per second */
+	{0x21, 0x30},
+	/* 2 measurements per second */
+	{0x22, 0x36},
+	/* 4 measurements per second */
+	{0x23, 0x34},
+	/* 10 measurements per second */
+	{0x27, 0x37},
+};
+
+/* periodic measure commands (low power mode) */
+static const char periodic_measure_commands_lpm[][SHT3X_CMD_LENGTH] = {
+	/* 0.5 measurements per second */
+	{0x20, 0x2f},
+	/* 1 measurements per second */
+	{0x21, 0x2d},
+	/* 2 measurements per second */
+	{0x22, 0x2b},
+	/* 4 measurements per second */
+	{0x23, 0x29},
+	/* 10 measurements per second */
+	{0x27, 0x2a},
+};
+
+struct sht3x_limit_commands {
+	const char read_command[SHT3X_CMD_LENGTH];
+	const char write_command[SHT3X_CMD_LENGTH];
+};
+
+static const struct sht3x_limit_commands limit_commands[] = {
+	/* temp1_max, humidity1_max */
+	[limit_max] = { {0xe1, 0x1f}, {0x61, 0x1d} },
+	/* temp_1_max_hyst, humidity1_max_hyst */
+	[limit_max_hyst] = { {0xe1, 0x14}, {0x61, 0x16} },
+	/* temp1_min, humidity1_min */
+	[limit_min] = { {0xe1, 0x02}, {0x61, 0x00} },
+	/* temp_1_min_hyst, humidity1_min_hyst */
+	[limit_min_hyst] = { {0xe1, 0x09}, {0x61, 0x0B} },
+};
+
+#define SHT3X_NUM_LIMIT_CMD  ARRAY_SIZE(limit_commands)
+
+static const u16 mode_to_update_interval[] = {
+	   0,
+	2000,
+	1000,
+	 500,
+	 250,
+	 100,
+};
+
+struct sht3x_data {
+	struct i2c_client *client;
+	struct mutex i2c_lock; /* lock for sending i2c commands */
+	struct mutex data_lock; /* lock for updating driver data */
+
+	u8 mode;
+	const unsigned char *command;
+	u32 wait_time;			/* in us*/
+	unsigned long last_update;	/* last update in periodic mode*/
+
+	struct sht3x_platform_data setup;
+
+	/*
+	 * cached values for temperature and humidity and limits
+	 * the limits arrays have the following order:
+	 * max, max_hyst, min, min_hyst
+	 */
+	int temperature;
+	int temperature_limits[SHT3X_NUM_LIMIT_CMD];
+	u32 humidity;
+	u32 humidity_limits[SHT3X_NUM_LIMIT_CMD];
+};
+
+static u8 get_mode_from_update_interval(u16 value)
+{
+	size_t index;
+	u8 number_of_modes = ARRAY_SIZE(mode_to_update_interval);
+
+	if (value == 0)
+		return 0;
+
+	/* find next faster update interval */
+	for (index = 1; index < number_of_modes; index++) {
+		if (mode_to_update_interval[index] <= value)
+			return index;
+	}
+
+	return number_of_modes - 1;
+}
+
+static int sht3x_read_from_command(struct i2c_client *client,
+				   struct sht3x_data *data,
+				   const char *command,
+				   char *buf, int length, u32 wait_time)
+{
+	int ret;
+
+	mutex_lock(&data->i2c_lock);
+	ret = i2c_master_send(client, command, SHT3X_CMD_LENGTH);
+
+	if (ret != SHT3X_CMD_LENGTH) {
+		ret = ret < 0 ? ret : -EIO;
+		goto out;
+	}
+
+	if (wait_time)
+		usleep_range(wait_time, wait_time + 1000);
+
+	ret = i2c_master_recv(client, buf, length);
+	if (ret != length) {
+		ret = ret < 0 ? ret : -EIO;
+		goto out;
+	}
+
+	ret = 0;
+out:
+	mutex_unlock(&data->i2c_lock);
+	return ret;
+}
+
+static int sht3x_extract_temperature(u16 raw)
+{
+	/*
+	 * From datasheet:
+	 * T = -45 + 175 * ST / 2^16
+	 * Adapted for integer fixed point (3 digit) arithmetic.
+	 */
+	return ((21875 * (int)raw) >> 13) - 45000;
+}
+
+static u32 sht3x_extract_humidity(u16 raw)
+{
+	/*
+	 * From datasheet:
+	 * RH = 100 * SRH / 2^16
+	 * Adapted for integer fixed point (3 digit) arithmetic.
+	 */
+	return (12500 * (u32)raw) >> 13;
+}
+
+static struct sht3x_data *sht3x_update_client(struct device *dev)
+{
+	struct sht3x_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
+	u16 interval_ms = mode_to_update_interval[data->mode];
+	unsigned long interval_jiffies = msecs_to_jiffies(interval_ms);
+	unsigned char buf[SHT3X_RESPONSE_LENGTH];
+	u16 val;
+	int ret = 0;
+
+	mutex_lock(&data->data_lock);
+	/*
+	 * Only update cached readings once per update interval in periodic
+	 * mode. In single shot mode the sensor measures values on demand, so
+	 * every time the sysfs interface is called, a measurement is triggered.
+	 * In periodic mode however, the measurement process is handled
+	 * internally by the sensor and reading out sensor values only makes
+	 * sense if a new reading is available.
+	 */
+	if (time_after(jiffies, data->last_update + interval_jiffies)) {
+		ret = sht3x_read_from_command(client, data, data->command, buf,
+					      sizeof(buf), data->wait_time);
+		if (ret)
+			goto out;
+
+		val = be16_to_cpup((__be16 *)buf);
+		data->temperature = sht3x_extract_temperature(val);
+		val = be16_to_cpup((__be16 *)(buf + 3));
+		data->humidity = sht3x_extract_humidity(val);
+		data->last_update = jiffies;
+	}
+
+out:
+	mutex_unlock(&data->data_lock);
+	if (ret)
+		return ERR_PTR(ret);
+
+	return data;
+}
+
+/* sysfs attributes */
+static ssize_t temp1_input_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct sht3x_data *data = sht3x_update_client(dev);
+
+	if (IS_ERR(data))
+		return PTR_ERR(data);
+
+	return sprintf(buf, "%d\n", data->temperature);
+}
+
+static ssize_t humidity1_input_show(struct device *dev,
+				    struct device_attribute *attr, char *buf)
+{
+	struct sht3x_data *data = sht3x_update_client(dev);
+
+	if (IS_ERR(data))
+		return PTR_ERR(data);
+
+	return sprintf(buf, "%u\n", data->humidity);
+}
+
+/*
+ * limits_update must only be called from probe or with data_lock held
+ */
+static int limits_update(struct sht3x_data *data)
+{
+	int ret;
+	u8 index;
+	int temperature;
+	u32 humidity;
+	u16 raw;
+	char buffer[SHT3X_RESPONSE_LENGTH];
+	const struct sht3x_limit_commands *commands;
+	struct i2c_client *client = data->client;
+
+	for (index = 0; index < SHT3X_NUM_LIMIT_CMD; index++) {
+		commands = &limit_commands[index];
+		ret = sht3x_read_from_command(client, data,
+					      commands->read_command, buffer,
+					      SHT3X_RESPONSE_LENGTH, 0);
+
+		if (ret)
+			return ret;
+
+		raw = be16_to_cpup((__be16 *)buffer);
+		temperature = sht3x_extract_temperature((raw & 0x01ff) << 7);
+		humidity = sht3x_extract_humidity(raw & 0xfe00);
+		data->temperature_limits[index] = temperature;
+		data->humidity_limits[index] = humidity;
+	}
+
+	return ret;
+}
+
+static ssize_t temp1_limit_show(struct device *dev,
+				struct device_attribute *attr,
+				char *buf)
+{
+	struct sht3x_data *data = dev_get_drvdata(dev);
+	u8 index = to_sensor_dev_attr(attr)->index;
+	int temperature_limit = data->temperature_limits[index];
+
+	return scnprintf(buf, PAGE_SIZE, "%d\n", temperature_limit);
+}
+
+static ssize_t humidity1_limit_show(struct device *dev,
+				    struct device_attribute *attr,
+				    char *buf)
+{
+	struct sht3x_data *data = dev_get_drvdata(dev);
+	u8 index = to_sensor_dev_attr(attr)->index;
+	u32 humidity_limit = data->humidity_limits[index];
+
+	return scnprintf(buf, PAGE_SIZE, "%u\n", humidity_limit);
+}
+
+/*
+ * limit_store must only be called with data_lock held
+ */
+static size_t limit_store(struct device *dev,
+			  size_t count,
+			  u8 index,
+			  int temperature,
+			  u32 humidity)
+{
+	char buffer[SHT3X_CMD_LENGTH + SHT3X_WORD_LEN + SHT3X_CRC8_LEN];
+	char *position = buffer;
+	int ret;
+	u16 raw;
+	struct sht3x_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
+	const struct sht3x_limit_commands *commands;
+
+	commands = &limit_commands[index];
+
+	memcpy(position, commands->write_command, SHT3X_CMD_LENGTH);
+	position += SHT3X_CMD_LENGTH;
+	/*
+	 * ST = (T + 45) / 175 * 2^16
+	 * SRH = RH / 100 * 2^16
+	 * adapted for fixed point arithmetic and packed the same as
+	 * in limit_show()
+	 */
+	raw = ((u32)(temperature + 45000) * 24543) >> (16 + 7);
+	raw |= ((humidity * 42950) >> 16) & 0xfe00;
+
+	*((__be16 *)position) = cpu_to_be16(raw);
+	position += SHT3X_WORD_LEN;
+	*position = crc8(sht3x_crc8_table,
+			 position - SHT3X_WORD_LEN,
+			 SHT3X_WORD_LEN,
+			 SHT3X_CRC8_INIT);
+
+	mutex_lock(&data->i2c_lock);
+	ret = i2c_master_send(client, buffer, sizeof(buffer));
+	mutex_unlock(&data->i2c_lock);
+
+	if (ret != sizeof(buffer))
+		return ret < 0 ? ret : -EIO;
+
+	data->temperature_limits[index] = temperature;
+	data->humidity_limits[index] = humidity;
+	return count;
+}
+
+static ssize_t temp1_limit_store(struct device *dev,
+				 struct device_attribute *attr,
+				 const char *buf,
+				 size_t count)
+{
+	int temperature;
+	int ret;
+	struct sht3x_data *data = dev_get_drvdata(dev);
+	u8 index = to_sensor_dev_attr(attr)->index;
+
+	ret = kstrtoint(buf, 0, &temperature);
+	if (ret)
+		return ret;
+
+	temperature = clamp_val(temperature, SHT3X_MIN_TEMPERATURE,
+				SHT3X_MAX_TEMPERATURE);
+	mutex_lock(&data->data_lock);
+	ret = limit_store(dev, count, index, temperature,
+			  data->humidity_limits[index]);
+	mutex_unlock(&data->data_lock);
+
+	return ret;
+}
+
+static ssize_t humidity1_limit_store(struct device *dev,
+				     struct device_attribute *attr,
+				     const char *buf,
+				     size_t count)
+{
+	u32 humidity;
+	int ret;
+	struct sht3x_data *data = dev_get_drvdata(dev);
+	u8 index = to_sensor_dev_attr(attr)->index;
+
+	ret = kstrtou32(buf, 0, &humidity);
+	if (ret)
+		return ret;
+
+	humidity = clamp_val(humidity, SHT3X_MIN_HUMIDITY, SHT3X_MAX_HUMIDITY);
+	mutex_lock(&data->data_lock);
+	ret = limit_store(dev, count, index, data->temperature_limits[index],
+			  humidity);
+	mutex_unlock(&data->data_lock);
+
+	return ret;
+}
+
+static void sht3x_select_command(struct sht3x_data *data)
+{
+	/*
+	 * In blocking mode (clock stretching mode) the I2C bus
+	 * is blocked for other traffic, thus the call to i2c_master_recv()
+	 * will wait until the data is ready. For non blocking mode, we
+	 * have to wait ourselves.
+	 */
+	if (data->mode > 0) {
+		data->command = sht3x_cmd_measure_periodic_mode;
+		data->wait_time = 0;
+	} else if (data->setup.blocking_io) {
+		data->command = data->setup.high_precision ?
+				sht3x_cmd_measure_blocking_hpm :
+				sht3x_cmd_measure_blocking_lpm;
+		data->wait_time = 0;
+	} else {
+		if (data->setup.high_precision) {
+			data->command = sht3x_cmd_measure_nonblocking_hpm;
+			data->wait_time = SHT3X_NONBLOCKING_WAIT_TIME_HPM;
+		} else {
+			data->command = sht3x_cmd_measure_nonblocking_lpm;
+			data->wait_time = SHT3X_NONBLOCKING_WAIT_TIME_LPM;
+		}
+	}
+}
+
+static int status_register_read(struct device *dev,
+				struct device_attribute *attr,
+				char *buffer, int length)
+{
+	int ret;
+	struct sht3x_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
+
+	ret = sht3x_read_from_command(client, data, sht3x_cmd_read_status_reg,
+				      buffer, length, 0);
+
+	return ret;
+}
+
+static ssize_t temp1_alarm_show(struct device *dev,
+				struct device_attribute *attr,
+				char *buf)
+{
+	char buffer[SHT3X_WORD_LEN + SHT3X_CRC8_LEN];
+	int ret;
+
+	ret = status_register_read(dev, attr, buffer,
+				   SHT3X_WORD_LEN + SHT3X_CRC8_LEN);
+	if (ret)
+		return ret;
+
+	return scnprintf(buf, PAGE_SIZE, "%d\n", !!(buffer[0] & 0x04));
+}
+
+static ssize_t humidity1_alarm_show(struct device *dev,
+				    struct device_attribute *attr,
+				    char *buf)
+{
+	char buffer[SHT3X_WORD_LEN + SHT3X_CRC8_LEN];
+	int ret;
+
+	ret = status_register_read(dev, attr, buffer,
+				   SHT3X_WORD_LEN + SHT3X_CRC8_LEN);
+	if (ret)
+		return ret;
+
+	return scnprintf(buf, PAGE_SIZE, "%d\n", !!(buffer[0] & 0x08));
+}
+
+static ssize_t heater_enable_show(struct device *dev,
+				  struct device_attribute *attr,
+				  char *buf)
+{
+	char buffer[SHT3X_WORD_LEN + SHT3X_CRC8_LEN];
+	int ret;
+
+	ret = status_register_read(dev, attr, buffer,
+				   SHT3X_WORD_LEN + SHT3X_CRC8_LEN);
+	if (ret)
+		return ret;
+
+	return scnprintf(buf, PAGE_SIZE, "%d\n", !!(buffer[0] & 0x20));
+}
+
+static ssize_t heater_enable_store(struct device *dev,
+				   struct device_attribute *attr,
+				   const char *buf,
+				   size_t count)
+{
+	struct sht3x_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
+	int ret;
+	bool status;
+
+	ret = kstrtobool(buf, &status);
+	if (ret)
+		return ret;
+
+	mutex_lock(&data->i2c_lock);
+
+	if (status)
+		ret = i2c_master_send(client, (char *)&sht3x_cmd_heater_on,
+				      SHT3X_CMD_LENGTH);
+	else
+		ret = i2c_master_send(client, (char *)&sht3x_cmd_heater_off,
+				      SHT3X_CMD_LENGTH);
+
+	mutex_unlock(&data->i2c_lock);
+
+	return ret;
+}
+
+static ssize_t update_interval_show(struct device *dev,
+				    struct device_attribute *attr,
+				    char *buf)
+{
+	struct sht3x_data *data = dev_get_drvdata(dev);
+
+	return scnprintf(buf, PAGE_SIZE, "%u\n",
+			 mode_to_update_interval[data->mode]);
+}
+
+static ssize_t update_interval_store(struct device *dev,
+				     struct device_attribute *attr,
+				     const char *buf,
+				     size_t count)
+{
+	u16 update_interval;
+	u8 mode;
+	int ret;
+	const char *command;
+	struct sht3x_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
+
+	ret = kstrtou16(buf, 0, &update_interval);
+	if (ret)
+		return ret;
+
+	mode = get_mode_from_update_interval(update_interval);
+
+	mutex_lock(&data->data_lock);
+	/* mode did not change */
+	if (mode == data->mode) {
+		mutex_unlock(&data->data_lock);
+		return count;
+	}
+
+	mutex_lock(&data->i2c_lock);
+	/*
+	 * Abort periodic measure mode.
+	 * To do any changes to the configuration while in periodic mode, we
+	 * have to send a break command to the sensor, which then falls back
+	 * to single shot (mode = 0).
+	 */
+	if (data->mode > 0) {
+		ret = i2c_master_send(client, sht3x_cmd_break,
+				      SHT3X_CMD_LENGTH);
+		if (ret != SHT3X_CMD_LENGTH)
+			goto out;
+		data->mode = 0;
+	}
+
+	if (mode > 0) {
+		if (data->setup.high_precision)
+			command = periodic_measure_commands_hpm[mode - 1];
+		else
+			command = periodic_measure_commands_lpm[mode - 1];
+
+		/* select mode */
+		ret = i2c_master_send(client, command, SHT3X_CMD_LENGTH);
+		if (ret != SHT3X_CMD_LENGTH)
+			goto out;
+	}
+
+	/* select mode and command */
+	data->mode = mode;
+	sht3x_select_command(data);
+
+out:
+	mutex_unlock(&data->i2c_lock);
+	mutex_unlock(&data->data_lock);
+	if (ret != SHT3X_CMD_LENGTH)
+		return ret < 0 ? ret : -EIO;
+
+	return count;
+}
+
+static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, temp1_input_show, NULL, 0);
+static SENSOR_DEVICE_ATTR(humidity1_input, S_IRUGO, humidity1_input_show,
+			  NULL, 0);
+static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO | S_IWUSR,
+			  temp1_limit_show, temp1_limit_store,
+			  limit_max);
+static SENSOR_DEVICE_ATTR(humidity1_max, S_IRUGO | S_IWUSR,
+			  humidity1_limit_show, humidity1_limit_store,
+			  limit_max);
+static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IRUGO | S_IWUSR,
+			  temp1_limit_show, temp1_limit_store,
+			  limit_max_hyst);
+static SENSOR_DEVICE_ATTR(humidity1_max_hyst, S_IRUGO | S_IWUSR,
+			  humidity1_limit_show, humidity1_limit_store,
+			  limit_max_hyst);
+static SENSOR_DEVICE_ATTR(temp1_min, S_IRUGO | S_IWUSR,
+			  temp1_limit_show, temp1_limit_store,
+			  limit_min);
+static SENSOR_DEVICE_ATTR(humidity1_min, S_IRUGO | S_IWUSR,
+			  humidity1_limit_show, humidity1_limit_store,
+			  limit_min);
+static SENSOR_DEVICE_ATTR(temp1_min_hyst, S_IRUGO | S_IWUSR,
+			  temp1_limit_show, temp1_limit_store,
+			  limit_min_hyst);
+static SENSOR_DEVICE_ATTR(humidity1_min_hyst, S_IRUGO | S_IWUSR,
+			  humidity1_limit_show, humidity1_limit_store,
+			  limit_min_hyst);
+static SENSOR_DEVICE_ATTR(temp1_alarm, S_IRUGO, temp1_alarm_show, NULL, 0);
+static SENSOR_DEVICE_ATTR(humidity1_alarm, S_IRUGO, humidity1_alarm_show,
+			  NULL, 0);
+static SENSOR_DEVICE_ATTR(heater_enable, S_IRUGO | S_IWUSR,
+			  heater_enable_show, heater_enable_store, 0);
+static SENSOR_DEVICE_ATTR(update_interval, S_IRUGO | S_IWUSR,
+			  update_interval_show, update_interval_store, 0);
+
+static struct attribute *sht3x_attrs[] = {
+	&sensor_dev_attr_temp1_input.dev_attr.attr,
+	&sensor_dev_attr_humidity1_input.dev_attr.attr,
+	&sensor_dev_attr_temp1_max.dev_attr.attr,
+	&sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
+	&sensor_dev_attr_humidity1_max.dev_attr.attr,
+	&sensor_dev_attr_humidity1_max_hyst.dev_attr.attr,
+	&sensor_dev_attr_temp1_min.dev_attr.attr,
+	&sensor_dev_attr_temp1_min_hyst.dev_attr.attr,
+	&sensor_dev_attr_humidity1_min.dev_attr.attr,
+	&sensor_dev_attr_humidity1_min_hyst.dev_attr.attr,
+	&sensor_dev_attr_temp1_alarm.dev_attr.attr,
+	&sensor_dev_attr_humidity1_alarm.dev_attr.attr,
+	&sensor_dev_attr_heater_enable.dev_attr.attr,
+	&sensor_dev_attr_update_interval.dev_attr.attr,
+	NULL
+};
+
+static struct attribute *sts3x_attrs[] = {
+	&sensor_dev_attr_temp1_input.dev_attr.attr,
+	NULL
+};
+
+ATTRIBUTE_GROUPS(sht3x);
+ATTRIBUTE_GROUPS(sts3x);
+
+static int sht3x_probe(struct i2c_client *client,
+		       const struct i2c_device_id *id)
+{
+	int ret;
+	struct sht3x_data *data;
+	struct device *hwmon_dev;
+	struct i2c_adapter *adap = client->adapter;
+	struct device *dev = &client->dev;
+	const struct attribute_group **attribute_groups;
+
+	/*
+	 * we require full i2c support since the sht3x uses multi-byte read and
+	 * writes as well as multi-byte commands which are not supported by
+	 * the smbus protocol
+	 */
+	if (!i2c_check_functionality(adap, I2C_FUNC_I2C))
+		return -ENODEV;
+
+	ret = i2c_master_send(client, sht3x_cmd_clear_status_reg,
+			      SHT3X_CMD_LENGTH);
+	if (ret != SHT3X_CMD_LENGTH)
+		return ret < 0 ? ret : -ENODEV;
+
+	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->setup.blocking_io = false;
+	data->setup.high_precision = true;
+	data->mode = 0;
+	data->last_update = 0;
+	data->client = client;
+	crc8_populate_msb(sht3x_crc8_table, SHT3X_CRC8_POLYNOMIAL);
+
+	if (client->dev.platform_data)
+		data->setup = *(struct sht3x_platform_data *)dev->platform_data;
+
+	sht3x_select_command(data);
+
+	mutex_init(&data->i2c_lock);
+	mutex_init(&data->data_lock);
+
+	ret = limits_update(data);
+	if (ret)
+		return ret;
+
+	if (id->driver_data == sts3x)
+		attribute_groups = sts3x_groups;
+	else
+		attribute_groups = sht3x_groups;
+
+	hwmon_dev = devm_hwmon_device_register_with_groups(dev,
+							   client->name,
+							   data,
+							   attribute_groups);
+
+	if (IS_ERR(hwmon_dev))
+		dev_dbg(dev, "unable to register hwmon device\n");
+
+	return PTR_ERR_OR_ZERO(hwmon_dev);
+}
+
+/* device ID table */
+static const struct i2c_device_id sht3x_ids[] = {
+	{"sht3x", sht3x},
+	{"sts3x", sts3x},
+	{}
+};
+
+MODULE_DEVICE_TABLE(i2c, sht3x_ids);
+
+static struct i2c_driver sht3x_i2c_driver = {
+	.driver.name = "sht3x",
+	.probe       = sht3x_probe,
+	.id_table    = sht3x_ids,
+};
+
+module_i2c_driver(sht3x_i2c_driver);
+
+MODULE_AUTHOR("David Frey <[e-mail]>");
+MODULE_AUTHOR("Pascal Sachs <[e-mail]>");
+MODULE_DESCRIPTION("Sensirion SHT3x humidity and temperature sensor driver");
+MODULE_LICENSE("GPL");

drivers/hwmon/tmp102.c

···
  * 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
  */
 
+#include <linux/delay.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/slab.h>
···
 #include <linux/mutex.h>
 #include <linux/device.h>
 #include <linux/jiffies.h>
+#include <linux/regmap.h>
 #include <linux/thermal.h>
 #include <linux/of.h>
 
···
 #define	TMP102_TLOW_REG			0x02
 #define	TMP102_THIGH_REG		0x03
 
+#define TMP102_CONFREG_MASK	(TMP102_CONF_SD | TMP102_CONF_TM | \
+				 TMP102_CONF_POL | TMP102_CONF_F0 | \
+				 TMP102_CONF_F1 | TMP102_CONF_OS | \
+				 TMP102_CONF_EM | TMP102_CONF_AL | \
+				 TMP102_CONF_CR0 | TMP102_CONF_CR1)
+
+#define TMP102_CONFIG_CLEAR	(TMP102_CONF_SD | TMP102_CONF_OS | \
+				 TMP102_CONF_CR0)
+#define TMP102_CONFIG_SET	(TMP102_CONF_TM | TMP102_CONF_EM | \
+				 TMP102_CONF_CR1)
+
+#define CONVERSION_TIME_MS		35	/* in milli-seconds */
+
 struct tmp102 {
-	struct i2c_client *client;
-	struct device *hwmon_dev;
-	struct mutex lock;
+	struct regmap *regmap;
 	u16 config_orig;
-	unsigned long last_update;
-	int temp[3];
-	bool first_time;
+	unsigned long ready_time;
 };
 
 /* convert left adjusted 13-bit TMP102 register value to milliCelsius */
···
 	return (val * 128) / 1000;
 }
 
-static const u8 tmp102_reg[] = {
-	TMP102_TEMP_REG,
-	TMP102_TLOW_REG,
-	TMP102_THIGH_REG,
-};
-
-static struct tmp102 *tmp102_update_device(struct device *dev)
-{
-	struct tmp102 *tmp102 = dev_get_drvdata(dev);
-	struct i2c_client *client = tmp102->client;
-
-	mutex_lock(&tmp102->lock);
-	if (time_after(jiffies, tmp102->last_update + HZ / 3)) {
-		int i;
-		for (i = 0; i < ARRAY_SIZE(tmp102->temp); ++i) {
-			int status = i2c_smbus_read_word_swapped(client,
-								 tmp102_reg[i]);
-			if (status > -1)
-				tmp102->temp[i] = tmp102_reg_to_mC(status);
-		}
-		tmp102->last_update = jiffies;
-		tmp102->first_time = false;
-	}
-	mutex_unlock(&tmp102->lock);
-	return tmp102;
-}
-
 static int tmp102_read_temp(void *dev, int *temp)
 {
-	struct tmp102 *tmp102 = tmp102_update_device(dev);
+	struct tmp102 *tmp102 = dev_get_drvdata(dev);
+	unsigned int reg;
+	int ret;
 
-	/* Is it too early even to return a conversion? */
-	if (tmp102->first_time) {
+	if (time_before(jiffies, tmp102->ready_time)) {
 		dev_dbg(dev, "%s: Conversion not ready yet..\n", __func__);
 		return -EAGAIN;
 	}
 
-	*temp = tmp102->temp[0];
+	ret = regmap_read(tmp102->regmap, TMP102_TEMP_REG, &reg);
+	if (ret < 0)
+		return ret;
+
+	*temp = tmp102_reg_to_mC(reg);
 
 	return 0;
 }
···
 				char *buf)
 {
 	struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
-	struct tmp102 *tmp102 = tmp102_update_device(dev);
+	struct tmp102 *tmp102 = dev_get_drvdata(dev);
+	int regaddr = sda->index;
+	unsigned int reg;
+	int err;
 
-	/* Is it too early even to return a read? */
-	if (tmp102->first_time)
+	if (regaddr == TMP102_TEMP_REG &&
+	    time_before(jiffies, tmp102->ready_time))
 		return -EAGAIN;
 
-	return sprintf(buf, "%d\n", tmp102->temp[sda->index]);
+	err = regmap_read(tmp102->regmap, regaddr, &reg);
+	if (err < 0)
+		return err;
+
+	return sprintf(buf, "%d\n", tmp102_reg_to_mC(reg));
 }
 
 static ssize_t tmp102_set_temp(struct device *dev,
···
 {
 	struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
 	struct tmp102 *tmp102 = dev_get_drvdata(dev);
-	struct i2c_client *client = tmp102->client;
+	int reg = sda->index;
 	long val;
-	int status;
+	int err;
 
 	if (kstrtol(buf, 10, &val) < 0)
 		return -EINVAL;
 	val = clamp_val(val, -256000, 255000);
 
-	mutex_lock(&tmp102->lock);
-	tmp102->temp[sda->index] = val;
-	status = i2c_smbus_write_word_swapped(client, tmp102_reg[sda->index],
-					      tmp102_mC_to_reg(val));
-	mutex_unlock(&tmp102->lock);
-	return status ? : count;
+	err = regmap_write(tmp102->regmap, reg, tmp102_mC_to_reg(val));
+	return err ? : count;
 }
 
-static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, tmp102_show_temp, NULL , 0);
+static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, tmp102_show_temp, NULL,
+			  TMP102_TEMP_REG);
 
 static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO, tmp102_show_temp,
-			  tmp102_set_temp, 1);
+			  tmp102_set_temp, TMP102_TLOW_REG);
 
 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, tmp102_show_temp,
-			  tmp102_set_temp, 2);
+			  tmp102_set_temp, TMP102_THIGH_REG);
 
 static struct attribute *tmp102_attrs[] = {
 	&sensor_dev_attr_temp1_input.dev_attr.attr,
···
 };
 ATTRIBUTE_GROUPS(tmp102);
 
-#define TMP102_CONFIG  (TMP102_CONF_TM | TMP102_CONF_EM | TMP102_CONF_CR1)
-#define TMP102_CONFIG_RD_ONLY (TMP102_CONF_R0 | TMP102_CONF_R1 | TMP102_CONF_AL)
-
 static const struct thermal_zone_of_device_ops tmp102_of_thermal_ops = {
 	.get_temp = tmp102_read_temp,
+};
+
+static void tmp102_restore_config(void *data)
+{
+	struct tmp102 *tmp102 = data;
+
+	regmap_write(tmp102->regmap, TMP102_CONF_REG, tmp102->config_orig);
+}
+
+static bool tmp102_is_writeable_reg(struct device *dev, unsigned int reg)
+{
+	return reg != TMP102_TEMP_REG;
+}
+
+static bool tmp102_is_volatile_reg(struct device *dev, unsigned int reg)
+{
+	return reg == TMP102_TEMP_REG;
+}
+
+static const struct regmap_config tmp102_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 16,
+	.max_register = TMP102_THIGH_REG,
+	.writeable_reg = tmp102_is_writeable_reg,
+	.volatile_reg = tmp102_is_volatile_reg,
+	.val_format_endian = REGMAP_ENDIAN_BIG,
+	.cache_type = REGCACHE_RBTREE,
+	.use_single_rw = true,
 };
 
 static int tmp102_probe(struct i2c_client *client,
···
 	struct device *dev = &client->dev;
 	struct device *hwmon_dev;
 	struct tmp102 *tmp102;
-	int status;
+	unsigned int regval;
+	int err;
 
 	if (!i2c_check_functionality(client->adapter,
 				     I2C_FUNC_SMBUS_WORD_DATA)) {
···
 		return -ENOMEM;
 
 	i2c_set_clientdata(client, tmp102);
-	tmp102->client = client;
 
-	status = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
-	if (status < 0) {
+	tmp102->regmap = devm_regmap_init_i2c(client, &tmp102_regmap_config);
+	if (IS_ERR(tmp102->regmap))
+		return PTR_ERR(tmp102->regmap);
+
+	err = regmap_read(tmp102->regmap, TMP102_CONF_REG, &regval);
+	if (err < 0) {
 		dev_err(dev, "error reading config register\n");
-		return status;
+		return err;
 	}
-	tmp102->config_orig = status;
-	status = i2c_smbus_write_word_swapped(client, TMP102_CONF_REG,
-					      TMP102_CONFIG);
-	if (status < 0) {
+
+	if ((regval & ~TMP102_CONFREG_MASK) !=
+	    (TMP102_CONF_R0 | TMP102_CONF_R1)) {
+		dev_err(dev, "unexpected config register value\n");
+		return -ENODEV;
+	}
+
+	tmp102->config_orig = regval;
+
+	devm_add_action(dev, tmp102_restore_config, tmp102);
+
+	regval &= ~TMP102_CONFIG_CLEAR;
+	regval |= TMP102_CONFIG_SET;
+
+	err = regmap_write(tmp102->regmap, TMP102_CONF_REG, regval);
+	if (err < 0) {
 		dev_err(dev, "error writing config register\n");
-		goto fail_restore_config;
+		return err;
 	}
-	status = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
-	if (status < 0) {
-		dev_err(dev, "error reading config register\n");
-		goto fail_restore_config;
-	}
-	status &= ~TMP102_CONFIG_RD_ONLY;
-	if (status != TMP102_CONFIG) {
-		dev_err(dev, "config settings did not stick\n");
-		status = -ENODEV;
-		goto fail_restore_config;
-	}
-	tmp102->last_update = jiffies;
-	/* Mark that we are not ready with data until conversion is complete */
-	tmp102->first_time = true;
-	mutex_init(&tmp102->lock);
 
-	hwmon_dev = hwmon_device_register_with_groups(dev, client->name,
-						      tmp102, tmp102_groups);
+	tmp102->ready_time = jiffies;
+	if (tmp102->config_orig & TMP102_CONF_SD) {
+		/*
+		 * Mark that we are not ready with data until the first
+		 * conversion is complete
+		 */
+		tmp102->ready_time += msecs_to_jiffies(CONVERSION_TIME_MS);
+	}
+
+	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
+							   tmp102,
+							   tmp102_groups);
 	if (IS_ERR(hwmon_dev)) {
 		dev_dbg(dev, "unable to register hwmon device\n");
-		status = PTR_ERR(hwmon_dev);
-		goto fail_restore_config;
+		return PTR_ERR(hwmon_dev);
 	}
-	tmp102->hwmon_dev = hwmon_dev;
 	devm_thermal_zone_of_sensor_register(hwmon_dev, 0, hwmon_dev,
 					     &tmp102_of_thermal_ops);
 
 	dev_info(dev, "initialized\n");
-
-	return 0;
-
-fail_restore_config:
-	i2c_smbus_write_word_swapped(client, TMP102_CONF_REG,
-				     tmp102->config_orig);
-	return status;
-}
-
-static int tmp102_remove(struct i2c_client *client)
-{
-	struct tmp102 *tmp102 = i2c_get_clientdata(client);
-
-	hwmon_device_unregister(tmp102->hwmon_dev);
-
-	/* Stop monitoring if device was stopped originally */
-	if (tmp102->config_orig & TMP102_CONF_SD) {
-		int config;
-
-		config = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
-		if (config >= 0)
-			i2c_smbus_write_word_swapped(client, TMP102_CONF_REG,
-						     config | TMP102_CONF_SD);
-	}
 
 	return 0;
 }
···
 static int tmp102_suspend(struct device *dev)
 {
 	struct i2c_client *client = to_i2c_client(dev);
-	int config;
+	struct tmp102 *tmp102 = i2c_get_clientdata(client);
 
-	config = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
-	if (config < 0)
-		return config;
-
-	config |= TMP102_CONF_SD;
-	return i2c_smbus_write_word_swapped(client, TMP102_CONF_REG, config);
+	return regmap_update_bits(tmp102->regmap, TMP102_CONF_REG,
+				  TMP102_CONF_SD, TMP102_CONF_SD);
 }
 
 static int tmp102_resume(struct device *dev)
 {
 	struct i2c_client *client = to_i2c_client(dev);
-	int config;
+	struct tmp102 *tmp102 = i2c_get_clientdata(client);
+	int err;
 
-	config = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
-	if (config < 0)
-		return config;
+	err = regmap_update_bits(tmp102->regmap, TMP102_CONF_REG,
+				 TMP102_CONF_SD, 0);
 
-	config &= ~TMP102_CONF_SD;
-	return i2c_smbus_write_word_swapped(client, TMP102_CONF_REG, config);
+	tmp102->ready_time = jiffies + msecs_to_jiffies(CONVERSION_TIME_MS);
+
+	return err;
 }
 #endif /* CONFIG_PM */
 
···
 	.driver.name	= DRIVER_NAME,
 	.driver.pm	= &tmp102_dev_pm_ops,
 	.probe		= tmp102_probe,
-	.remove		= tmp102_remove,
 	.id_table	= tmp102_id,
 };
 

drivers/hwmon/tmp401.c

···
 static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4c, 0x4d,
 	0x4e, 0x4f, I2C_CLIENT_END };
 
-enum chips { tmp401, tmp411, tmp431, tmp432, tmp435 };
+enum chips { tmp401, tmp411, tmp431, tmp432, tmp435, tmp461 };
 
 /*
  * The TMP401 registers, note some registers have different addresses for
···
 #define TMP401_MANUFACTURER_ID_REG		0xFE
 #define TMP401_DEVICE_ID_REG			0xFF
 
-static const u8 TMP401_TEMP_MSB_READ[6][2] = {
+static const u8 TMP401_TEMP_MSB_READ[7][2] = {
 	{ 0x00, 0x01 },	/* temp */
 	{ 0x06, 0x08 },	/* low limit */
 	{ 0x05, 0x07 },	/* high limit */
 	{ 0x20, 0x19 },	/* therm (crit) limit */
 	{ 0x30, 0x34 },	/* lowest */
 	{ 0x32, 0x36 },	/* highest */
+	{ 0, 0x11 },	/* offset */
 };
 
-static const u8 TMP401_TEMP_MSB_WRITE[6][2] = {
+static const u8 TMP401_TEMP_MSB_WRITE[7][2] = {
 	{ 0, 0 },	/* temp (unused) */
 	{ 0x0C, 0x0E },	/* low limit */
 	{ 0x0B, 0x0D },	/* high limit */
 	{ 0x20, 0x19 },	/* therm (crit) limit */
 	{ 0x30, 0x34 },	/* lowest */
 	{ 0x32, 0x36 },	/* highest */
+	{ 0, 0x11 },	/* offset */
 };
 
-static const u8 TMP401_TEMP_LSB[6][2] = {
+static const u8 TMP401_TEMP_LSB[7][2] = {
 	{ 0x15, 0x10 },	/* temp */
 	{ 0x17, 0x14 },	/* low limit */
 	{ 0x16, 0x13 },	/* high limit */
 	{ 0, 0 },	/* therm (crit) limit (unused) */
 	{ 0x31, 0x35 },	/* lowest */
 	{ 0x33, 0x37 },	/* highest */
+	{ 0, 0x12 },	/* offset */
 };
 
 static const u8 TMP432_TEMP_MSB_READ[4][3] = {
···
 	{ "tmp431", tmp431 },
 	{ "tmp432", tmp432 },
 	{ "tmp435", tmp435 },
+	{ "tmp461", tmp461 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, tmp401_id);
···
 	/* register values */
 	u8 status[4];
 	u8 config;
-	u16 temp[6][3];
+	u16 temp[7][3];
 	u8 temp_crit_hyst;
 };
 
···
 };
 
 /*
+ * Additional features of the TMP461 chip.
+ * The TMP461 temperature offset for the remote channel.
+ */
+static SENSOR_DEVICE_ATTR_2(temp2_offset, S_IWUSR | S_IRUGO, show_temp,
+			    store_temp, 6, 1);
+
+static struct attribute *tmp461_attributes[] = {
+	&sensor_dev_attr_temp2_offset.dev_attr.attr,
+	NULL
+};
+
+static const struct attribute_group tmp461_group = {
+	.attrs = tmp461_attributes,
+};
+
+/*
  * Begin non sysfs callback code (aka Real code)
  */
 
···
 			const struct i2c_device_id *id)
 {
 	static const char * const names[] = {
-		"TMP401", "TMP411", "TMP431", "TMP432", "TMP435"
+		"TMP401", "TMP411", "TMP431", "TMP432", "TMP435", "TMP461"
 	};
 	struct device *dev = &client->dev;
 	struct device *hwmon_dev;
···
 	/* Register additional tmp432 sysfs hooks */
 	if (data->kind == tmp432)
 		data->groups[groups++] = &tmp432_group;
+
+	if (data->kind == tmp461)
+		data->groups[groups++] = &tmp461_group;
 
 	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
 							   data, data->groups);

include/linux/platform_data/sht3x.h

···
+/*
+ * Copyright (C) 2016 Sensirion AG, Switzerland
+ * Author: David Frey <[e-mail]>
+ * Author: Pascal Sachs <[e-mail]>
+ *
+ * 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.
+ *
+ */
+
+#ifndef __SHT3X_H_
+#define __SHT3X_H_
+
+struct sht3x_platform_data {
+	bool blocking_io;
+	bool high_precision;
+};
+#endif /* __SHT3X_H_ */