Merge tag 'hwmon-for-linus-v3.20' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging

Pull hwmon updates from Guenter Roeck:
 "Explicit support for ina231 added to ina2xx driver.

  Minor improvements, cleanup and fixes in various drivers"

* tag 'hwmon-for-linus-v3.20' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  hwmon: (tmp102) add hibernation callbacks
  hwmon: (ads2828) Only keep data in device data structure if needed
  hwmon: (ads2828) Convert to use regmap
  hwmon: (jc42) Allow negative hysteresis temperatures
  hwmon: (adc128d818) Do proper sign extension
  hwmon: (ad7314) Do proper sign extension
  hwmon: (abx500) Fix format string warnings
  hwmon: (jc42) Fix integer overflow when writing hysteresis value
  hwmon: (jc42) Fix integer overflow
  hwmon: (jc42) Use sign_extend32 for sign extension
  hwmon: (ina2xx) Add ina231 compatible string
  hwmon: (ina2xx) use DIV_ROUND_CLOSEST() to avoid rounding errors
  hwmon: (ina2xx) remove an unnecessary dev_get_drvdata() result check
  hwmon: (ina2xx) implement update_interval attribute for ina226
  hwmon: (ina2xx) make shunt resistance configurable at run-time
  hwmon: (ina2xx) don't accept shunt values greater than the calibration factor
  hwmon: (ina2xx) remove a stray new line
  hwmon: (ina2xx) reinitialize the chip in case it's been reset
  hwmon: (nct7802) Constify struct regmap_config

10 files changed, 375 insertions, 135 deletions

diff --git a/Documentation/hwmon/ina2xx b/Documentation/hwmon/ina2xx
index 4223c2d3b50..cfd31d94c87 100644
--- a/Documentation/hwmon/ina2xx
+++ b/Documentation/hwmon/ina2xx
@@ -26,6 +26,12 @@ Supported chips:
     Datasheet: Publicly available at the Texas Instruments website
                http://www.ti.com/
 
+  * Texas Instruments INA231
+    Prefix: 'ina231'
+    Addresses: I2C 0x40 - 0x4f
+    Datasheet: Publicly available at the Texas Instruments website
+               http://www.ti.com/
+
 Author: Lothar Felten <l-felten@ti.com>
 
 Description
@@ -41,9 +47,18 @@ interface. The INA220 monitors both shunt drop and supply voltage.
 The INA226 is a current shunt and power monitor with an I2C interface.
 The INA226 monitors both a shunt voltage drop and bus supply voltage.
 
-The INA230 is a high or low side current shunt and power monitor with an I2C
-interface. The INA230 monitors both a shunt voltage drop and bus supply voltage.
+INA230 and INA231 are high or low side current shunt and power monitors
+with an I2C interface. The chips monitor both a shunt voltage drop and
+bus supply voltage.
 
-The shunt value in micro-ohms can be set via platform data or device tree.
-Please refer to the Documentation/devicetree/bindings/i2c/ina2xx.txt for bindings
+The shunt value in micro-ohms can be set via platform data or device tree at
+compile-time or via the shunt_resistor attribute in sysfs at run-time. Please
+refer to the Documentation/devicetree/bindings/i2c/ina2xx.txt for bindings
 if the device tree is used.
+
+Additionally ina226 supports update_interval attribute as described in
+Documentation/hwmon/sysfs-interface. Internally the interval is the sum of
+bus and shunt voltage conversion times multiplied by the averaging rate. We
+don't touch the conversion times and only modify the number of averages. The
+lower limit of the update_interval is 2 ms, the upper limit is 2253 ms.
+The actual programmed interval may vary from the desired value.
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index a7de26d1ac8..d931cbbed24 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -1389,6 +1389,7 @@ config SENSORS_ADS1015
 config SENSORS_ADS7828
 	tristate "Texas Instruments ADS7828 and compatibles"
 	depends on I2C
+	select REGMAP_I2C
 	help
 	  If you say yes here you get support for Texas Instruments ADS7828 and
 	  ADS7830 8-channel A/D converters. ADS7828 resolution is 12-bit, while
@@ -1430,8 +1431,8 @@ config SENSORS_INA2XX
 	tristate "Texas Instruments INA219 and compatibles"
 	depends on I2C
 	help
-	  If you say yes here you get support for INA219, INA220, INA226, and
-	  INA230 power monitor chips.
+	  If you say yes here you get support for INA219, INA220, INA226,
+	  INA230, and INA231 power monitor chips.
 
 	  The INA2xx driver is configured for the default configuration of
 	  the part as described in the datasheet.
diff --git a/drivers/hwmon/abx500.c b/drivers/hwmon/abx500.c
index 13875968c84..6cb89c0ebab 100644
--- a/drivers/hwmon/abx500.c
+++ b/drivers/hwmon/abx500.c
@@ -221,7 +221,7 @@ static ssize_t show_min(struct device *dev,
 	struct abx500_temp *data = dev_get_drvdata(dev);
 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 
-	return sprintf(buf, "%ld\n", data->min[attr->index]);
+	return sprintf(buf, "%lu\n", data->min[attr->index]);
 }
 
 static ssize_t show_max(struct device *dev,
@@ -230,7 +230,7 @@ static ssize_t show_max(struct device *dev,
 	struct abx500_temp *data = dev_get_drvdata(dev);
 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 
-	return sprintf(buf, "%ld\n", data->max[attr->index]);
+	return sprintf(buf, "%lu\n", data->max[attr->index]);
 }
 
 static ssize_t show_max_hyst(struct device *dev,
@@ -239,7 +239,7 @@ static ssize_t show_max_hyst(struct device *dev,
 	struct abx500_temp *data = dev_get_drvdata(dev);
 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 
-	return sprintf(buf, "%ld\n", data->max_hyst[attr->index]);
+	return sprintf(buf, "%lu\n", data->max_hyst[attr->index]);
 }
 
 static ssize_t show_min_alarm(struct device *dev,
diff --git a/drivers/hwmon/ad7314.c b/drivers/hwmon/ad7314.c
index f4f9b219bf1..11955467fc0 100644
--- a/drivers/hwmon/ad7314.c
+++ b/drivers/hwmon/ad7314.c
@@ -16,6 +16,7 @@
 #include <linux/err.h>
 #include <linux/hwmon.h>
 #include <linux/hwmon-sysfs.h>
+#include <linux/bitops.h>
 
 /*
  * AD7314 temperature masks
@@ -67,7 +68,7 @@ static ssize_t ad7314_show_temperature(struct device *dev,
 	switch (spi_get_device_id(chip->spi_dev)->driver_data) {
 	case ad7314:
 		data = (ret & AD7314_TEMP_MASK) >> AD7314_TEMP_SHIFT;
-		data = (data << 6) >> 6;
+		data = sign_extend32(data, 9);
 
 		return sprintf(buf, "%d\n", 250 * data);
 	case adt7301:
@@ -78,7 +79,7 @@ static ssize_t ad7314_show_temperature(struct device *dev,
 		 * register.  1lsb - 31.25 milli degrees centigrade
 		 */
 		data = ret & ADT7301_TEMP_MASK;
-		data = (data << 2) >> 2;
+		data = sign_extend32(data, 13);
 
 		return sprintf(buf, "%d\n",
 			       DIV_ROUND_CLOSEST(data * 3125, 100));
diff --git a/drivers/hwmon/adc128d818.c b/drivers/hwmon/adc128d818.c
index 0625e50d7a6..ad2b47e4034 100644
--- a/drivers/hwmon/adc128d818.c
+++ b/drivers/hwmon/adc128d818.c
@@ -27,6 +27,7 @@
 #include <linux/err.h>
 #include <linux/regulator/consumer.h>
 #include <linux/mutex.h>
+#include <linux/bitops.h>
 
 /* Addresses to scan
  * The chip also supports addresses 0x35..0x37. Don't scan those addresses
@@ -189,7 +190,7 @@ static ssize_t adc128_show_temp(struct device *dev,
 	if (IS_ERR(data))
 		return PTR_ERR(data);
 
-	temp = (data->temp[index] << 7) >> 7;	/* sign extend */
+	temp = sign_extend32(data->temp[index], 8);
 	return sprintf(buf, "%d\n", temp * 500);/* 0.5 degrees C resolution */
 }
 
diff --git a/drivers/hwmon/ads7828.c b/drivers/hwmon/ads7828.c
index a622d40eec1..bce4e9ff21b 100644
--- a/drivers/hwmon/ads7828.c
+++ b/drivers/hwmon/ads7828.c
@@ -30,14 +30,12 @@
 #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/platform_data/ads7828.h>
+#include <linux/regmap.h>
 #include <linux/slab.h>
 
 /* The ADS7828 registers */
-#define ADS7828_NCH		8	/* 8 channels supported */
 #define ADS7828_CMD_SD_SE	0x80	/* Single ended inputs */
 #define ADS7828_CMD_PD1		0x04	/* Internal vref OFF && A/D ON */
 #define ADS7828_CMD_PD3		0x0C	/* Internal vref ON && A/D ON */
@@ -50,17 +48,9 @@ enum ads7828_chips { ads7828, ads7830 };
 
 /* Client specific data */
 struct ads7828_data {
-	struct i2c_client *client;
-	struct mutex update_lock;	/* Mutex protecting updates */
-	unsigned long last_updated;	/* Last updated time (in jiffies) */
-	u16 adc_input[ADS7828_NCH];	/* ADS7828_NCH samples */
-	bool valid;			/* Validity flag */
-	bool diff_input;		/* Differential input */
-	bool ext_vref;			/* External voltage reference */
-	unsigned int vref_mv;		/* voltage reference value */
+	struct regmap *regmap;
 	u8 cmd_byte;			/* Command byte without channel bits */
 	unsigned int lsb_resol;		/* Resolution of the ADC sample LSB */
-	s32 (*read_channel)(const struct i2c_client *client, u8 command);
 };
 
 /* Command byte C2,C1,C0 - see datasheet */
@@ -69,42 +59,22 @@ static inline u8 ads7828_cmd_byte(u8 cmd, int ch)
 	return cmd | (((ch >> 1) | (ch & 0x01) << 2) << 4);
 }
 
-/* Update data for the device (all 8 channels) */
-static struct ads7828_data *ads7828_update_device(struct device *dev)
-{
-	struct ads7828_data *data = dev_get_drvdata(dev);
-	struct i2c_client *client = data->client;
-
-	mutex_lock(&data->update_lock);
-
-	if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
-			|| !data->valid) {
-		unsigned int ch;
-		dev_dbg(&client->dev, "Starting ads7828 update\n");
-
-		for (ch = 0; ch < ADS7828_NCH; ch++) {
-			u8 cmd = ads7828_cmd_byte(data->cmd_byte, ch);
-			data->adc_input[ch] = data->read_channel(client, cmd);
-		}
-		data->last_updated = jiffies;
-		data->valid = true;
-	}
-
-	mutex_unlock(&data->update_lock);
-
-	return data;
-}
-
 /* sysfs callback function */
 static ssize_t ads7828_show_in(struct device *dev, struct device_attribute *da,
 			       char *buf)
 {
 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
-	struct ads7828_data *data = ads7828_update_device(dev);
-	unsigned int value = DIV_ROUND_CLOSEST(data->adc_input[attr->index] *
-					       data->lsb_resol, 1000);
+	struct ads7828_data *data = dev_get_drvdata(dev);
+	u8 cmd = ads7828_cmd_byte(data->cmd_byte, attr->index);
+	unsigned int regval;
+	int err;
 
-	return sprintf(buf, "%d\n", value);
+	err = regmap_read(data->regmap, cmd, &regval);
+	if (err < 0)
+		return err;
+
+	return sprintf(buf, "%d\n",
+		       DIV_ROUND_CLOSEST(regval * data->lsb_resol, 1000));
 }
 
 static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, ads7828_show_in, NULL, 0);
@@ -130,6 +100,16 @@ static struct attribute *ads7828_attrs[] = {
 
 ATTRIBUTE_GROUPS(ads7828);
 
+static const struct regmap_config ads2828_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 16,
+};
+
+static const struct regmap_config ads2830_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+};
+
 static int ads7828_probe(struct i2c_client *client,
 			 const struct i2c_device_id *id)
 {
@@ -137,42 +117,40 @@ static int ads7828_probe(struct i2c_client *client,
 	struct ads7828_platform_data *pdata = dev_get_platdata(dev);
 	struct ads7828_data *data;
 	struct device *hwmon_dev;
+	unsigned int vref_mv = ADS7828_INT_VREF_MV;
+	bool diff_input = false;
+	bool ext_vref = false;
 
 	data = devm_kzalloc(dev, sizeof(struct ads7828_data), GFP_KERNEL);
 	if (!data)
 		return -ENOMEM;
 
 	if (pdata) {
-		data->diff_input = pdata->diff_input;
-		data->ext_vref = pdata->ext_vref;
-		if (data->ext_vref)
-			data->vref_mv = pdata->vref_mv;
+		diff_input = pdata->diff_input;
+		ext_vref = pdata->ext_vref;
+		if (ext_vref && pdata->vref_mv)
+			vref_mv = pdata->vref_mv;
 	}
 
-	/* Bound Vref with min/max values if it was provided */
-	if (data->vref_mv)
-		data->vref_mv = clamp_val(data->vref_mv,
-					  ADS7828_EXT_VREF_MV_MIN,
-					  ADS7828_EXT_VREF_MV_MAX);
-	else
-		data->vref_mv = ADS7828_INT_VREF_MV;
+	/* Bound Vref with min/max values */
+	vref_mv = clamp_val(vref_mv, ADS7828_EXT_VREF_MV_MIN,
+			    ADS7828_EXT_VREF_MV_MAX);
 
 	/* ADS7828 uses 12-bit samples, while ADS7830 is 8-bit */
 	if (id->driver_data == ads7828) {
-		data->lsb_resol = DIV_ROUND_CLOSEST(data->vref_mv * 1000, 4096);
-		data->read_channel = i2c_smbus_read_word_swapped;
+		data->lsb_resol = DIV_ROUND_CLOSEST(vref_mv * 1000, 4096);
+		data->regmap = devm_regmap_init_i2c(client,
+						    &ads2828_regmap_config);
 	} else {
-		data->lsb_resol = DIV_ROUND_CLOSEST(data->vref_mv * 1000, 256);
-		data->read_channel = i2c_smbus_read_byte_data;
+		data->lsb_resol = DIV_ROUND_CLOSEST(vref_mv * 1000, 256);
+		data->regmap = devm_regmap_init_i2c(client,
+						    &ads2830_regmap_config);
 	}
 
-	data->cmd_byte = data->ext_vref ? ADS7828_CMD_PD1 : ADS7828_CMD_PD3;
-	if (!data->diff_input)
+	data->cmd_byte = ext_vref ? ADS7828_CMD_PD1 : ADS7828_CMD_PD3;
+	if (!diff_input)
 		data->cmd_byte |= ADS7828_CMD_SD_SE;
 
-	data->client = client;
-	mutex_init(&data->update_lock);
-
 	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
 							   data,
 							   ads7828_groups);
diff --git a/drivers/hwmon/ina2xx.c b/drivers/hwmon/ina2xx.c
index e01feba909c..d1542b7d4bc 100644
--- a/drivers/hwmon/ina2xx.c
+++ b/drivers/hwmon/ina2xx.c
@@ -35,6 +35,7 @@
 #include <linux/hwmon-sysfs.h>
 #include <linux/jiffies.h>
 #include <linux/of.h>
+#include <linux/delay.h>
 
 #include <linux/platform_data/ina2xx.h>
 
@@ -51,7 +52,6 @@
 #define INA226_ALERT_LIMIT		0x07
 #define INA226_DIE_ID			0xFF
 
-
 /* register count */
 #define INA219_REGISTERS		6
 #define INA226_REGISTERS		8
@@ -64,6 +64,24 @@
 
 /* worst case is 68.10 ms (~14.6Hz, ina219) */
 #define INA2XX_CONVERSION_RATE		15
+#define INA2XX_MAX_DELAY		69 /* worst case delay in ms */
+
+#define INA2XX_RSHUNT_DEFAULT		10000
+
+/* bit mask for reading the averaging setting in the configuration register */
+#define INA226_AVG_RD_MASK		0x0E00
+
+#define INA226_READ_AVG(reg)		(((reg) & INA226_AVG_RD_MASK) >> 9)
+#define INA226_SHIFT_AVG(val)		((val) << 9)
+
+/* common attrs, ina226 attrs and NULL */
+#define INA2XX_MAX_ATTRIBUTE_GROUPS	3
+
+/*
+ * Both bus voltage and shunt voltage conversion times for ina226 are set
+ * to 0b0100 on POR, which translates to 2200 microseconds in total.
+ */
+#define INA226_TOTAL_CONV_TIME_DEFAULT	2200
 
 enum ina2xx_ids { ina219, ina226 };
 
@@ -81,11 +99,16 @@ struct ina2xx_data {
 	struct i2c_client *client;
 	const struct ina2xx_config *config;
 
+	long rshunt;
+	u16 curr_config;
+
 	struct mutex update_lock;
 	bool valid;
 	unsigned long last_updated;
+	int update_interval; /* in jiffies */
 
 	int kind;
+	const struct attribute_group *groups[INA2XX_MAX_ATTRIBUTE_GROUPS];
 	u16 regs[INA2XX_MAX_REGISTERS];
 };
 
@@ -110,34 +133,156 @@ static const struct ina2xx_config ina2xx_config[] = {
 	},
 };
 
-static struct ina2xx_data *ina2xx_update_device(struct device *dev)
+/*
+ * Available averaging rates for ina226. The indices correspond with
+ * the bit values expected by the chip (according to the ina226 datasheet,
+ * table 3 AVG bit settings, found at
+ * http://www.ti.com/lit/ds/symlink/ina226.pdf.
+ */
+static const int ina226_avg_tab[] = { 1, 4, 16, 64, 128, 256, 512, 1024 };
+
+static int ina226_avg_bits(int avg)
+{
+	int i;
+
+	/* Get the closest average from the tab. */
+	for (i = 0; i < ARRAY_SIZE(ina226_avg_tab) - 1; i++) {
+		if (avg <= (ina226_avg_tab[i] + ina226_avg_tab[i + 1]) / 2)
+			break;
+	}
+
+	return i; /* Return 0b0111 for values greater than 1024. */
+}
+
+static int ina226_reg_to_interval(u16 config)
+{
+	int avg = ina226_avg_tab[INA226_READ_AVG(config)];
+
+	/*
+	 * Multiply the total conversion time by the number of averages.
+	 * Return the result in milliseconds.
+	 */
+	return DIV_ROUND_CLOSEST(avg * INA226_TOTAL_CONV_TIME_DEFAULT, 1000);
+}
+
+static u16 ina226_interval_to_reg(int interval, u16 config)
+{
+	int avg, avg_bits;
+
+	avg = DIV_ROUND_CLOSEST(interval * 1000,
+				INA226_TOTAL_CONV_TIME_DEFAULT);
+	avg_bits = ina226_avg_bits(avg);
+
+	return (config & ~INA226_AVG_RD_MASK) | INA226_SHIFT_AVG(avg_bits);
+}
+
+static void ina226_set_update_interval(struct ina2xx_data *data)
+{
+	int ms;
+
+	ms = ina226_reg_to_interval(data->curr_config);
+	data->update_interval = msecs_to_jiffies(ms);
+}
+
+static int ina2xx_calibrate(struct ina2xx_data *data)
+{
+	u16 val = DIV_ROUND_CLOSEST(data->config->calibration_factor,
+				    data->rshunt);
+
+	return i2c_smbus_write_word_swapped(data->client,
+					    INA2XX_CALIBRATION, val);
+}
+
+/*
+ * Initialize the configuration and calibration registers.
+ */
+static int ina2xx_init(struct ina2xx_data *data)
 {
-	struct ina2xx_data *data = dev_get_drvdata(dev);
 	struct i2c_client *client = data->client;
-	struct ina2xx_data *ret = data;
+	int ret;
 
-	mutex_lock(&data->update_lock);
+	/* device configuration */
+	ret = i2c_smbus_write_word_swapped(client, INA2XX_CONFIG,
+					   data->curr_config);
+	if (ret < 0)
+		return ret;
 
-	if (time_after(jiffies, data->last_updated +
-		       HZ / INA2XX_CONVERSION_RATE) || !data->valid) {
+	/*
+	 * Set current LSB to 1mA, shunt is in uOhms
+	 * (equation 13 in datasheet).
+	 */
+	return ina2xx_calibrate(data);
+}
 
-		int i;
+static int ina2xx_do_update(struct device *dev)
+{
+	struct ina2xx_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
+	int i, rv, retry;
 
-		dev_dbg(&client->dev, "Starting ina2xx update\n");
+	dev_dbg(&client->dev, "Starting ina2xx update\n");
 
+	for (retry = 5; retry; retry--) {
 		/* Read all registers */
 		for (i = 0; i < data->config->registers; i++) {
-			int rv = i2c_smbus_read_word_swapped(client, i);
-			if (rv < 0) {
-				ret = ERR_PTR(rv);
-				goto abort;
-			}
+			rv = i2c_smbus_read_word_swapped(client, i);
+			if (rv < 0)
+				return rv;
 			data->regs[i] = rv;
 		}
+
+		/*
+		 * If the current value in the calibration register is 0, the
+		 * power and current registers will also remain at 0. In case
+		 * the chip has been reset let's check the calibration
+		 * register and reinitialize if needed.
+		 */
+		if (data->regs[INA2XX_CALIBRATION] == 0) {
+			dev_warn(dev, "chip not calibrated, reinitializing\n");
+
+			rv = ina2xx_init(data);
+			if (rv < 0)
+				return rv;
+
+			/*
+			 * Let's make sure the power and current registers
+			 * have been updated before trying again.
+			 */
+			msleep(INA2XX_MAX_DELAY);
+			continue;
+		}
+
 		data->last_updated = jiffies;
 		data->valid = 1;
+
+		return 0;
 	}
-abort:
+
+	/*
+	 * If we're here then although all write operations succeeded, the
+	 * chip still returns 0 in the calibration register. Nothing more we
+	 * can do here.
+	 */
+	dev_err(dev, "unable to reinitialize the chip\n");
+	return -ENODEV;
+}
+
+static struct ina2xx_data *ina2xx_update_device(struct device *dev)
+{
+	struct ina2xx_data *data = dev_get_drvdata(dev);
+	struct ina2xx_data *ret = data;
+	unsigned long after;
+	int rv;
+
+	mutex_lock(&data->update_lock);
+
+	after = data->last_updated + data->update_interval;
+	if (time_after(jiffies, after) || !data->valid) {
+		rv = ina2xx_do_update(dev);
+		if (rv < 0)
+			ret = ERR_PTR(rv);
+	}
+
 	mutex_unlock(&data->update_lock);
 	return ret;
 }
@@ -164,6 +309,10 @@ static int ina2xx_get_value(struct ina2xx_data *data, u8 reg)
 		/* signed register, LSB=1mA (selected), in mA */
 		val = (s16)data->regs[reg];
 		break;
+	case INA2XX_CALIBRATION:
+		val = DIV_ROUND_CLOSEST(data->config->calibration_factor,
+					data->regs[reg]);
+		break;
 	default:
 		/* programmer goofed */
 		WARN_ON_ONCE(1);
@@ -187,6 +336,85 @@ static ssize_t ina2xx_show_value(struct device *dev,
 			ina2xx_get_value(data, attr->index));
 }
 
+static ssize_t ina2xx_set_shunt(struct device *dev,
+				struct device_attribute *da,
+				const char *buf, size_t count)
+{
+	struct ina2xx_data *data = ina2xx_update_device(dev);
+	unsigned long val;
+	int status;
+
+	if (IS_ERR(data))
+		return PTR_ERR(data);
+
+	status = kstrtoul(buf, 10, &val);
+	if (status < 0)
+		return status;
+
+	if (val == 0 ||
+	    /* Values greater than the calibration factor make no sense. */
+	    val > data->config->calibration_factor)
+		return -EINVAL;
+
+	mutex_lock(&data->update_lock);
+	data->rshunt = val;
+	status = ina2xx_calibrate(data);
+	mutex_unlock(&data->update_lock);
+	if (status < 0)
+		return status;
+
+	return count;
+}
+
+static ssize_t ina226_set_interval(struct device *dev,
+				   struct device_attribute *da,
+				   const char *buf, size_t count)
+{
+	struct ina2xx_data *data = dev_get_drvdata(dev);
+	unsigned long val;
+	int status;
+
+	status = kstrtoul(buf, 10, &val);
+	if (status < 0)
+		return status;
+
+	if (val > INT_MAX || val == 0)
+		return -EINVAL;
+
+	mutex_lock(&data->update_lock);
+	data->curr_config = ina226_interval_to_reg(val,
+						   data->regs[INA2XX_CONFIG]);
+	status = i2c_smbus_write_word_swapped(data->client,
+					      INA2XX_CONFIG,
+					      data->curr_config);
+
+	ina226_set_update_interval(data);
+	/* Make sure the next access re-reads all registers. */
+	data->valid = 0;
+	mutex_unlock(&data->update_lock);
+	if (status < 0)
+		return status;
+
+	return count;
+}
+
+static ssize_t ina226_show_interval(struct device *dev,
+				    struct device_attribute *da, char *buf)
+{
+	struct ina2xx_data *data = ina2xx_update_device(dev);
+
+	if (IS_ERR(data))
+		return PTR_ERR(data);
+
+	/*
+	 * We don't use data->update_interval here as we want to display
+	 * the actual interval used by the chip and jiffies_to_msecs()
+	 * doesn't seem to be accurate enough.
+	 */
+	return snprintf(buf, PAGE_SIZE, "%d\n",
+			ina226_reg_to_interval(data->regs[INA2XX_CONFIG]));
+}
+
 /* shunt voltage */
 static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, ina2xx_show_value, NULL,
 			  INA2XX_SHUNT_VOLTAGE);
@@ -203,15 +431,37 @@ static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO, ina2xx_show_value, NULL,
 static SENSOR_DEVICE_ATTR(power1_input, S_IRUGO, ina2xx_show_value, NULL,
 			  INA2XX_POWER);
 
+/* shunt resistance */
+static SENSOR_DEVICE_ATTR(shunt_resistor, S_IRUGO | S_IWUSR,
+			  ina2xx_show_value, ina2xx_set_shunt,
+			  INA2XX_CALIBRATION);
+
+/* update interval (ina226 only) */
+static SENSOR_DEVICE_ATTR(update_interval, S_IRUGO | S_IWUSR,
+			  ina226_show_interval, ina226_set_interval, 0);
+
 /* pointers to created device attributes */
 static struct attribute *ina2xx_attrs[] = {
 	&sensor_dev_attr_in0_input.dev_attr.attr,
 	&sensor_dev_attr_in1_input.dev_attr.attr,
 	&sensor_dev_attr_curr1_input.dev_attr.attr,
 	&sensor_dev_attr_power1_input.dev_attr.attr,
+	&sensor_dev_attr_shunt_resistor.dev_attr.attr,
 	NULL,
 };
-ATTRIBUTE_GROUPS(ina2xx);
+
+static const struct attribute_group ina2xx_group = {
+	.attrs = ina2xx_attrs,
+};
+
+static struct attribute *ina226_attrs[] = {
+	&sensor_dev_attr_update_interval.dev_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group ina226_group = {
+	.attrs = ina226_attrs,
+};
 
 static int ina2xx_probe(struct i2c_client *client,
 			const struct i2c_device_id *id)
@@ -221,9 +471,8 @@ static int ina2xx_probe(struct i2c_client *client,
 	struct device *dev = &client->dev;
 	struct ina2xx_data *data;
 	struct device *hwmon_dev;
-	long shunt = 10000; /* default shunt value 10mOhms */
 	u32 val;
-	int ret;
+	int ret, group = 0;
 
 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA))
 		return -ENODEV;
@@ -234,50 +483,52 @@ static int ina2xx_probe(struct i2c_client *client,
 
 	if (dev_get_platdata(dev)) {
 		pdata = dev_get_platdata(dev);
-		shunt = pdata->shunt_uohms;
+		data->rshunt = pdata->shunt_uohms;
 	} else if (!of_property_read_u32(dev->of_node,
 					 "shunt-resistor", &val)) {
-		shunt = val;
+		data->rshunt = val;
+	} else {
+		data->rshunt = INA2XX_RSHUNT_DEFAULT;
 	}
 
-	if (shunt <= 0)
-		return -ENODEV;
-
 	/* set the device type */
 	data->kind = id->driver_data;
 	data->config = &ina2xx_config[data->kind];
-
-	/* device configuration */
-	ret = i2c_smbus_write_word_swapped(client, INA2XX_CONFIG,
-					   data->config->config_default);
-	if (ret < 0) {
-		dev_err(dev,
-			"error writing to the config register: %d", ret);
-		return -ENODEV;
-	}
+	data->curr_config = data->config->config_default;
+	data->client = client;
 
 	/*
-	 * Set current LSB to 1mA, shunt is in uOhms
-	 * (equation 13 in datasheet).
+	 * Ina226 has a variable update_interval. For ina219 we
+	 * use a constant value.
 	 */
-	ret = i2c_smbus_write_word_swapped(client, INA2XX_CALIBRATION,
-				data->config->calibration_factor / shunt);
+	if (data->kind == ina226)
+		ina226_set_update_interval(data);
+	else
+		data->update_interval = HZ / INA2XX_CONVERSION_RATE;
+
+	if (data->rshunt <= 0 ||
+	    data->rshunt > data->config->calibration_factor)
+		return -ENODEV;
+
+	ret = ina2xx_init(data);
 	if (ret < 0) {
-		dev_err(dev,
-			"error writing to the calibration register: %d", ret);
+		dev_err(dev, "error configuring the device: %d\n", ret);
 		return -ENODEV;
 	}
 
-	data->client = client;
 	mutex_init(&data->update_lock);
 
+	data->groups[group++] = &ina2xx_group;
+	if (data->kind == ina226)
+		data->groups[group++] = &ina226_group;
+
 	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
-							   data, ina2xx_groups);
+							   data, data->groups);
 	if (IS_ERR(hwmon_dev))
 		return PTR_ERR(hwmon_dev);
 
 	dev_info(dev, "power monitor %s (Rshunt = %li uOhm)\n",
-		 id->name, shunt);
+		 id->name, data->rshunt);
 
 	return 0;
 }
@@ -287,6 +538,7 @@ static const struct i2c_device_id ina2xx_id[] = {
 	{ "ina220", ina219 },
 	{ "ina226", ina226 },
 	{ "ina230", ina226 },
+	{ "ina231", ina226 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, ina2xx_id);
diff --git a/drivers/hwmon/jc42.c b/drivers/hwmon/jc42.c
index 388f8bcd898..996bdfd5cf2 100644
--- a/drivers/hwmon/jc42.c
+++ b/drivers/hwmon/jc42.c
@@ -201,7 +201,7 @@ struct jc42_data {
 #define JC42_TEMP_MIN		0
 #define JC42_TEMP_MAX		125000
 
-static u16 jc42_temp_to_reg(int temp, bool extended)
+static u16 jc42_temp_to_reg(long temp, bool extended)
 {
 	int ntemp = clamp_val(temp,
 			      extended ? JC42_TEMP_MIN_EXTENDED :
@@ -213,11 +213,7 @@ static u16 jc42_temp_to_reg(int temp, bool extended)
 
 static int jc42_temp_from_reg(s16 reg)
 {
-	reg &= 0x1fff;
-
-	/* sign extend register */
-	if (reg & 0x1000)
-		reg |= 0xf000;
+	reg = sign_extend32(reg, 12);
 
 	/* convert from 0.0625 to 0.001 resolution */
 	return reg * 125 / 2;
@@ -308,15 +304,18 @@ static ssize_t set_temp_crit_hyst(struct device *dev,
 				  const char *buf, size_t count)
 {
 	struct jc42_data *data = dev_get_drvdata(dev);
-	unsigned long val;
+	long val;
 	int diff, hyst;
 	int err;
 	int ret = count;
 
-	if (kstrtoul(buf, 10, &val) < 0)
+	if (kstrtol(buf, 10, &val) < 0)
 		return -EINVAL;
 
+	val = clamp_val(val, (data->extended ? JC42_TEMP_MIN_EXTENDED :
+			      JC42_TEMP_MIN) - 6000, JC42_TEMP_MAX);
 	diff = jc42_temp_from_reg(data->temp[t_crit]) - val;
+
 	hyst = 0;
 	if (diff > 0) {
 		if (diff < 2250)
diff --git a/drivers/hwmon/nct7802.c b/drivers/hwmon/nct7802.c
index ec5678289e4..55765790907 100644
--- a/drivers/hwmon/nct7802.c
+++ b/drivers/hwmon/nct7802.c
@@ -779,7 +779,7 @@ static bool nct7802_regmap_is_volatile(struct device *dev, unsigned int reg)
 	return reg != REG_BANK && reg <= 0x20;
 }
 
-static struct regmap_config nct7802_regmap_config = {
+static const struct regmap_config nct7802_regmap_config = {
 	.reg_bits = 8,
 	.val_bits = 8,
 	.cache_type = REGCACHE_RBTREE,
diff --git a/drivers/hwmon/tmp102.c b/drivers/hwmon/tmp102.c
index ba9f478f64e..9da2735f142 100644
--- a/drivers/hwmon/tmp102.c
+++ b/drivers/hwmon/tmp102.c
@@ -253,7 +253,7 @@ static int tmp102_remove(struct i2c_client *client)
 	return 0;
 }
 
-#ifdef CONFIG_PM
+#ifdef CONFIG_PM_SLEEP
 static int tmp102_suspend(struct device *dev)
 {
 	struct i2c_client *client = to_i2c_client(dev);
@@ -279,17 +279,10 @@ static int tmp102_resume(struct device *dev)
 	config &= ~TMP102_CONF_SD;
 	return i2c_smbus_write_word_swapped(client, TMP102_CONF_REG, config);
 }
-
-static const struct dev_pm_ops tmp102_dev_pm_ops = {
-	.suspend	= tmp102_suspend,
-	.resume		= tmp102_resume,
-};
-
-#define TMP102_DEV_PM_OPS (&tmp102_dev_pm_ops)
-#else
-#define	TMP102_DEV_PM_OPS NULL
 #endif /* CONFIG_PM */
 
+static SIMPLE_DEV_PM_OPS(tmp102_dev_pm_ops, tmp102_suspend, tmp102_resume);
+
 static const struct i2c_device_id tmp102_id[] = {
 	{ "tmp102", 0 },
 	{ }
@@ -298,7 +291,7 @@ MODULE_DEVICE_TABLE(i2c, tmp102_id);
 
 static struct i2c_driver tmp102_driver = {
 	.driver.name	= DRIVER_NAME,
-	.driver.pm	= TMP102_DEV_PM_OPS,
+	.driver.pm	= &tmp102_dev_pm_ops,
 	.probe		= tmp102_probe,
 	.remove		= tmp102_remove,
 	.id_table	= tmp102_id,