hwmon: Driver for Texas Instruments INA209

Add support for the TI / Burr-Brown INA209 voltage / current / power
monitor.

Cc: Paul Hays <haysp@magma.net>
Cc: Ira W. Snyder <iws@ovro.caltech.edu>
Tested-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

diff --git a/Documentation/devicetree/bindings/i2c/ina209.txt b/Documentation/devicetree/bindings/i2c/ina209.txt
new file mode 100644 (file)
index 0000000..9dd2bee
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/ina209.txt
@@ -0,0 +1,18 @@
+ina209 properties
+
+Required properties:
+- compatible: Must be "ti,ina209"
+- reg: I2C address
+
+Optional properties:
+
+- shunt-resistor
+       Shunt resistor value in micro-Ohm
+
+Example:
+
+temp-sensor@4c {
+       compatible = "ti,ina209";
+       reg = <0x4c>;
+       shunt-resistor = <5000>;
+};

diff --git a/Documentation/hwmon/ina209 b/Documentation/hwmon/ina209
new file mode 100644 (file)
index 0000000..672501d
--- /dev/null
+++ b/Documentation/hwmon/ina209
@@ -0,0 +1,93 @@
+Kernel driver ina209
+=====================
+
+Supported chips:
+  * Burr-Brown / Texas Instruments INA209
+    Prefix: 'ina209'
+    Addresses scanned: -
+    Datasheet:
+        http://www.ti.com/lit/gpn/ina209
+
+Author: Paul Hays <Paul.Hays@cattail.ca>
+Author: Ira W. Snyder <iws@ovro.caltech.edu>
+Author: Guenter Roeck <linux@roeck-us.net>
+
+
+Description
+-----------
+
+The TI / Burr-Brown INA209 monitors voltage, current, and power on the high side
+of a D.C. power supply. It can perform measurements and calculations in the
+background to supply readings at any time. It includes a programmable
+calibration multiplier to scale the displayed current and power values.
+
+
+Sysfs entries
+-------------
+
+The INA209 chip is highly configurable both via hardwiring and via
+the I2C bus. See the datasheet for details.
+
+This tries to expose most monitoring features of the hardware via
+sysfs. It does not support every feature of this chip.
+
+
+in0_input              shunt voltage (mV)
+in0_input_highest      shunt voltage historical maximum reading (mV)
+in0_input_lowest       shunt voltage historical minimum reading (mV)
+in0_reset_history      reset shunt voltage history
+in0_max                        shunt voltage max alarm limit (mV)
+in0_min                        shunt voltage min alarm limit (mV)
+in0_crit_max           shunt voltage crit max alarm limit (mV)
+in0_crit_min           shunt voltage crit min alarm limit (mV)
+in0_max_alarm          shunt voltage max alarm limit exceeded
+in0_min_alarm          shunt voltage min alarm limit exceeded
+in0_crit_max_alarm     shunt voltage crit max alarm limit exceeded
+in0_crit_min_alarm     shunt voltage crit min alarm limit exceeded
+
+in1_input              bus voltage (mV)
+in1_input_highest      bus voltage historical maximum reading (mV)
+in1_input_lowest       bus voltage historical minimum reading (mV)
+in1_reset_history      reset bus voltage history
+in1_max                        bus voltage max alarm limit (mV)
+in1_min                        bus voltage min alarm limit (mV)
+in1_crit_max           bus voltage crit max alarm limit (mV)
+in1_crit_min           bus voltage crit min alarm limit (mV)
+in1_max_alarm          bus voltage max alarm limit exceeded
+in1_min_alarm          bus voltage min alarm limit exceeded
+in1_crit_max_alarm     bus voltage crit max alarm limit exceeded
+in1_crit_min_alarm     bus voltage crit min alarm limit exceeded
+
+power1_input           power measurement (uW)
+power1_input_highest   power historical maximum reading (uW)
+power1_reset_history   reset power history
+power1_max             power max alarm limit (uW)
+power1_crit            power crit alarm limit (uW)
+power1_max_alarm       power max alarm limit exceeded
+power1_crit_alarm      power crit alarm limit exceeded
+
+curr1_input            current measurement (mA)
+
+update_interval                data conversion time; affects number of samples used
+                       to average results for shunt and bus voltages.
+
+General Remarks
+---------------
+
+The power and current registers in this chip require that the calibration
+register is programmed correctly before they are used. Normally this is expected
+to be done in the BIOS. In the absence of BIOS programming, the shunt resistor
+voltage can be provided using platform data. The driver uses platform data from
+the ina2xx driver for this purpose. If calibration register data is not provided
+via platform data, the driver checks if the calibration register has been
+programmed (ie has a value not equal to zero). If so, this value is retained.
+Otherwise, a default value reflecting a shunt resistor value of 10 mOhm is
+programmed into the calibration register.
+
+
+Output Pins
+-----------
+
+Output pin programming is a board feature which depends on the BIOS. It is
+outside the scope of a hardware monitoring driver to enable or disable output
+pins.

diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 3588b2a0915c7e430d034f8f95f7c63e8861637d..5e77cef09ca61cddd2dff513996463e8b33dce6f 100644 (file)
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -1157,6 +1157,16 @@ config SENSORS_AMC6821
          This driver can also be build as a module.  If so, the module
          will be called amc6821.
 
+config SENSORS_INA209
+       tristate "TI / Burr Brown INA209"
+       depends on I2C
+       help
+         If you say yes here you get support for the TI / Burr Brown INA209
+         voltage / current / power monitor I2C interface.
+
+         This driver can also be built as a module. If so, the module will
+         be called ina209.
+
 config SENSORS_INA2XX
        tristate "Texas Instruments INA219 and compatibles"
        depends on I2C

diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index a37a82c64da260f0e7734f16dfb157bb6db58f5b..8d6d97ea7c1e3d9e161f425cb236c79fce18c295 100644 (file)
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -65,6 +65,7 @@ obj-$(CONFIG_SENSORS_ULTRA45) += ultra45_env.o
 obj-$(CONFIG_SENSORS_I5K_AMB)  += i5k_amb.o
 obj-$(CONFIG_SENSORS_IBMAEM)   += ibmaem.o
 obj-$(CONFIG_SENSORS_IBMPEX)   += ibmpex.o
+obj-$(CONFIG_SENSORS_INA209)   += ina209.o
 obj-$(CONFIG_SENSORS_INA2XX)   += ina2xx.o
 obj-$(CONFIG_SENSORS_IT87)     += it87.o
 obj-$(CONFIG_SENSORS_JC42)     += jc42.o

diff --git a/drivers/hwmon/ina209.c b/drivers/hwmon/ina209.c
new file mode 100644 (file)
index 0000000..c6fdd5b
--- /dev/null
+++ b/drivers/hwmon/ina209.c
@@ -0,0 +1,636 @@
+/*
+ * Driver for the Texas Instruments / Burr Brown INA209
+ * Bidirectional Current/Power Monitor
+ *
+ * Copyright (C) 2012 Guenter Roeck <linux@roeck-us.net>
+ *
+ * Derived from Ira W. Snyder's original driver submission
+ *     Copyright (C) 2008 Paul Hays <Paul.Hays@cattail.ca>
+ *     Copyright (C) 2008-2009 Ira W. Snyder <iws@ovro.caltech.edu>
+ *
+ * Aligned with ina2xx driver
+ *     Copyright (C) 2012 Lothar Felten <l-felten@ti.com>
+ *     Thanks to Jan Volkering
+ *
+ * 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; version 2 of the License.
+ *
+ * Datasheet:
+ * http://www.ti.com/lit/gpn/ina209
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/bug.h>
+#include <linux/i2c.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+
+#include <linux/platform_data/ina2xx.h>
+
+/* register definitions */
+#define INA209_CONFIGURATION           0x00
+#define INA209_STATUS                  0x01
+#define INA209_STATUS_MASK             0x02
+#define INA209_SHUNT_VOLTAGE           0x03
+#define INA209_BUS_VOLTAGE             0x04
+#define INA209_POWER                   0x05
+#define INA209_CURRENT                 0x06
+#define INA209_SHUNT_VOLTAGE_POS_PEAK  0x07
+#define INA209_SHUNT_VOLTAGE_NEG_PEAK  0x08
+#define INA209_BUS_VOLTAGE_MAX_PEAK    0x09
+#define INA209_BUS_VOLTAGE_MIN_PEAK    0x0a
+#define INA209_POWER_PEAK              0x0b
+#define INA209_SHUNT_VOLTAGE_POS_WARN  0x0c
+#define INA209_SHUNT_VOLTAGE_NEG_WARN  0x0d
+#define INA209_POWER_WARN              0x0e
+#define INA209_BUS_VOLTAGE_OVER_WARN   0x0f
+#define INA209_BUS_VOLTAGE_UNDER_WARN  0x10
+#define INA209_POWER_OVER_LIMIT                0x11
+#define INA209_BUS_VOLTAGE_OVER_LIMIT  0x12
+#define INA209_BUS_VOLTAGE_UNDER_LIMIT 0x13
+#define INA209_CRITICAL_DAC_POS                0x14
+#define INA209_CRITICAL_DAC_NEG                0x15
+#define INA209_CALIBRATION             0x16
+
+#define INA209_REGISTERS               0x17
+
+#define INA209_CONFIG_DEFAULT          0x3c47  /* PGA=8, full range */
+#define INA209_SHUNT_DEFAULT           10000   /* uOhm */
+
+struct ina209_data {
+       struct device *hwmon_dev;
+
+       struct mutex update_lock;
+       bool valid;
+       unsigned long last_updated;     /* in jiffies */
+
+       u16 regs[INA209_REGISTERS];     /* All chip registers */
+
+       u16 config_orig;                /* Original configuration */
+       u16 calibration_orig;           /* Original calibration */
+       u16 update_interval;
+};
+
+static struct ina209_data *ina209_update_device(struct device *dev)
+{
+       struct i2c_client *client = to_i2c_client(dev);
+       struct ina209_data *data = i2c_get_clientdata(client);
+       struct ina209_data *ret = data;
+       s32 val;
+       int i;
+
+       mutex_lock(&data->update_lock);
+
+       if (!data->valid ||
+           time_after(jiffies, data->last_updated + data->update_interval)) {
+               for (i = 0; i < ARRAY_SIZE(data->regs); i++) {
+                       val = i2c_smbus_read_word_swapped(client, i);
+                       if (val < 0) {
+                               ret = ERR_PTR(val);
+                               goto abort;
+                       }
+                       data->regs[i] = val;
+               }
+               data->last_updated = jiffies;
+               data->valid = true;
+       }
+abort:
+       mutex_unlock(&data->update_lock);
+       return ret;
+}
+
+/*
+ * Read a value from a device register and convert it to the
+ * appropriate sysfs units
+ */
+static long ina209_from_reg(const u8 reg, const u16 val)
+{
+       switch (reg) {
+       case INA209_SHUNT_VOLTAGE:
+       case INA209_SHUNT_VOLTAGE_POS_PEAK:
+       case INA209_SHUNT_VOLTAGE_NEG_PEAK:
+       case INA209_SHUNT_VOLTAGE_POS_WARN:
+       case INA209_SHUNT_VOLTAGE_NEG_WARN:
+               /* LSB=10 uV. Convert to mV. */
+               return DIV_ROUND_CLOSEST(val, 100);
+
+       case INA209_BUS_VOLTAGE:
+       case INA209_BUS_VOLTAGE_MAX_PEAK:
+       case INA209_BUS_VOLTAGE_MIN_PEAK:
+       case INA209_BUS_VOLTAGE_OVER_WARN:
+       case INA209_BUS_VOLTAGE_UNDER_WARN:
+       case INA209_BUS_VOLTAGE_OVER_LIMIT:
+       case INA209_BUS_VOLTAGE_UNDER_LIMIT:
+               /* LSB=4 mV, last 3 bits unused */
+               return (val >> 3) * 4;
+
+       case INA209_CRITICAL_DAC_POS:
+               /* LSB=1 mV, in the upper 8 bits */
+               return val >> 8;
+
+       case INA209_CRITICAL_DAC_NEG:
+               /* LSB=1 mV, in the upper 8 bits */
+               return -1 * (val >> 8);
+
+       case INA209_POWER:
+       case INA209_POWER_PEAK:
+       case INA209_POWER_WARN:
+       case INA209_POWER_OVER_LIMIT:
+               /* LSB=20 mW. Convert to uW */
+               return val * 20 * 1000L;
+
+       case INA209_CURRENT:
+               /* LSB=1 mA (selected). Is in mA */
+               return val;
+       }
+
+       /* programmer goofed */
+       WARN_ON_ONCE(1);
+       return 0;
+}
+
+/*
+ * Take a value and convert it to register format, clamping the value
+ * to the appropriate range.
+ */
+static int ina209_to_reg(u8 reg, u16 old, long val)
+{
+       switch (reg) {
+       case INA209_SHUNT_VOLTAGE_POS_WARN:
+       case INA209_SHUNT_VOLTAGE_NEG_WARN:
+               /* Limit to +- 320 mV, 10 uV LSB */
+               return clamp_val(val, -320, 320) * 100;
+
+       case INA209_BUS_VOLTAGE_OVER_WARN:
+       case INA209_BUS_VOLTAGE_UNDER_WARN:
+       case INA209_BUS_VOLTAGE_OVER_LIMIT:
+       case INA209_BUS_VOLTAGE_UNDER_LIMIT:
+               /*
+                * Limit to 0-32000 mV, 4 mV LSB
+                *
+                * The last three bits aren't part of the value, but we'll
+                * preserve them in their original state.
+                */
+               return (DIV_ROUND_CLOSEST(clamp_val(val, 0, 32000), 4) << 3)
+                 | (old & 0x7);
+
+       case INA209_CRITICAL_DAC_NEG:
+               /*
+                * Limit to -255-0 mV, 1 mV LSB
+                * Convert the value to a positive value for the register
+                *
+                * The value lives in the top 8 bits only, be careful
+                * and keep original value of other bits.
+                */
+               return (clamp_val(-val, 0, 255) << 8) | (old & 0xff);
+
+       case INA209_CRITICAL_DAC_POS:
+               /*
+                * Limit to 0-255 mV, 1 mV LSB
+                *
+                * The value lives in the top 8 bits only, be careful
+                * and keep original value of other bits.
+                */
+               return (clamp_val(val, 0, 255) << 8) | (old & 0xff);
+
+       case INA209_POWER_WARN:
+       case INA209_POWER_OVER_LIMIT:
+               /* 20 mW LSB */
+               return DIV_ROUND_CLOSEST(val, 20 * 1000);
+       }
+
+       /* Other registers are read-only, return access error */
+       return -EACCES;
+}
+
+static int ina209_interval_from_reg(u16 reg)
+{
+       return 68 >> (15 - ((reg >> 3) & 0x0f));
+}
+
+static u16 ina209_reg_from_interval(u16 config, long interval)
+{
+       int i, adc;
+
+       if (interval <= 0) {
+               adc = 8;
+       } else {
+               adc = 15;
+               for (i = 34 + 34 / 2; i; i >>= 1) {
+                       if (i < interval)
+                               break;
+                       adc--;
+               }
+       }
+       return (config & 0xf807) | (adc << 3) | (adc << 7);
+}
+
+static ssize_t ina209_set_interval(struct device *dev,
+                                  struct device_attribute *da,
+                                  const char *buf, size_t count)
+{
+       struct i2c_client *client = to_i2c_client(dev);
+       struct ina209_data *data = ina209_update_device(dev);
+       long val;
+       u16 regval;
+       int ret;
+
+       if (IS_ERR(data))
+               return PTR_ERR(data);
+
+       ret = kstrtol(buf, 10, &val);
+       if (ret < 0)
+               return ret;
+
+       mutex_lock(&data->update_lock);
+       regval = ina209_reg_from_interval(data->regs[INA209_CONFIGURATION],
+                                         val);
+       i2c_smbus_write_word_swapped(client, INA209_CONFIGURATION, regval);
+       data->regs[INA209_CONFIGURATION] = regval;
+       data->update_interval = ina209_interval_from_reg(regval);
+       mutex_unlock(&data->update_lock);
+       return count;
+}
+
+static ssize_t ina209_show_interval(struct device *dev,
+                                   struct device_attribute *da, char *buf)
+{
+       struct i2c_client *client = to_i2c_client(dev);
+       struct ina209_data *data = i2c_get_clientdata(client);
+
+       return snprintf(buf, PAGE_SIZE, "%d\n", data->update_interval);
+}
+
+/*
+ * History is reset by writing 1 into bit 0 of the respective peak register.
+ * Since more than one peak register may be affected by the scope of a
+ * reset_history attribute write, use a bit mask in attr->index to identify
+ * which registers are affected.
+ */
+static u16 ina209_reset_history_regs[] = {
+       INA209_SHUNT_VOLTAGE_POS_PEAK,
+       INA209_SHUNT_VOLTAGE_NEG_PEAK,
+       INA209_BUS_VOLTAGE_MAX_PEAK,
+       INA209_BUS_VOLTAGE_MIN_PEAK,
+       INA209_POWER_PEAK
+};
+
+static ssize_t ina209_reset_history(struct device *dev,
+                                   struct device_attribute *da,
+                                   const char *buf,
+                                   size_t count)
+{
+       struct i2c_client *client = to_i2c_client(dev);
+       struct ina209_data *data = i2c_get_clientdata(client);
+       struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+       u32 mask = attr->index;
+       long val;
+       int i, ret;
+
+       ret = kstrtol(buf, 10, &val);
+       if (ret < 0)
+               return ret;
+
+       mutex_lock(&data->update_lock);
+       for (i = 0; i < ARRAY_SIZE(ina209_reset_history_regs); i++) {
+               if (mask & (1 << i))
+                       i2c_smbus_write_word_swapped(client,
+                                       ina209_reset_history_regs[i], 1);
+       }
+       data->valid = false;
+       mutex_unlock(&data->update_lock);
+       return count;
+}
+
+static ssize_t ina209_set_value(struct device *dev,
+                               struct device_attribute *da,
+                               const char *buf,
+                               size_t count)
+{
+       struct i2c_client *client = to_i2c_client(dev);
+       struct ina209_data *data = ina209_update_device(dev);
+       struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+       int reg = attr->index;
+       long val;
+       int ret;
+
+       if (IS_ERR(data))
+               return PTR_ERR(data);
+
+       ret = kstrtol(buf, 10, &val);
+       if (ret < 0)
+               return ret;
+
+       mutex_lock(&data->update_lock);
+       ret = ina209_to_reg(reg, data->regs[reg], val);
+       if (ret < 0) {
+               count = ret;
+               goto abort;
+       }
+       i2c_smbus_write_word_swapped(client, reg, ret);
+       data->regs[reg] = ret;
+abort:
+       mutex_unlock(&data->update_lock);
+       return count;
+}
+
+static ssize_t ina209_show_value(struct device *dev,
+                                struct device_attribute *da,
+                                char *buf)
+{
+       struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+       struct ina209_data *data = ina209_update_device(dev);
+       long val;
+
+       if (IS_ERR(data))
+               return PTR_ERR(data);
+
+       val = ina209_from_reg(attr->index, data->regs[attr->index]);
+       return snprintf(buf, PAGE_SIZE, "%ld\n", val);
+}
+
+static ssize_t ina209_show_alarm(struct device *dev,
+                                struct device_attribute *da,
+                                char *buf)
+{
+       struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+       struct ina209_data *data = ina209_update_device(dev);
+       const unsigned int mask = attr->index;
+       u16 status;
+
+       if (IS_ERR(data))
+               return PTR_ERR(data);
+
+       status = data->regs[INA209_STATUS];
+
+       /*
+        * All alarms are in the INA209_STATUS register. To avoid a long
+        * switch statement, the mask is passed in attr->index
+        */
+       return snprintf(buf, PAGE_SIZE, "%u\n", !!(status & mask));
+}
+
+/* Shunt voltage, history, limits, alarms */
+static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, ina209_show_value, NULL,
+                         INA209_SHUNT_VOLTAGE);
+static SENSOR_DEVICE_ATTR(in0_input_highest, S_IRUGO, ina209_show_value, NULL,
+                         INA209_SHUNT_VOLTAGE_POS_PEAK);
+static SENSOR_DEVICE_ATTR(in0_input_lowest, S_IRUGO, ina209_show_value, NULL,
+                         INA209_SHUNT_VOLTAGE_NEG_PEAK);
+static SENSOR_DEVICE_ATTR(in0_reset_history, S_IWUSR, NULL,
+                         ina209_reset_history, (1 << 0) | (1 << 1));
+static SENSOR_DEVICE_ATTR(in0_max, S_IRUGO | S_IWUSR, ina209_show_value,
+                         ina209_set_value, INA209_SHUNT_VOLTAGE_POS_WARN);
+static SENSOR_DEVICE_ATTR(in0_min, S_IRUGO | S_IWUSR, ina209_show_value,
+                         ina209_set_value, INA209_SHUNT_VOLTAGE_NEG_WARN);
+static SENSOR_DEVICE_ATTR(in0_crit_max, S_IRUGO | S_IWUSR, ina209_show_value,
+                         ina209_set_value, INA209_CRITICAL_DAC_POS);
+static SENSOR_DEVICE_ATTR(in0_crit_min, S_IRUGO | S_IWUSR, ina209_show_value,
+                         ina209_set_value, INA209_CRITICAL_DAC_NEG);
+
+static SENSOR_DEVICE_ATTR(in0_min_alarm,  S_IRUGO, ina209_show_alarm, NULL,
+                         1 << 11);
+static SENSOR_DEVICE_ATTR(in0_max_alarm, S_IRUGO, ina209_show_alarm, NULL,
+                         1 << 12);
+static SENSOR_DEVICE_ATTR(in0_crit_min_alarm, S_IRUGO, ina209_show_alarm, NULL,
+                         1 << 6);
+static SENSOR_DEVICE_ATTR(in0_crit_max_alarm, S_IRUGO, ina209_show_alarm, NULL,
+                         1 << 7);
+
+/* Bus voltage, history, limits, alarms */
+static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, ina209_show_value, NULL,
+                         INA209_BUS_VOLTAGE);
+static SENSOR_DEVICE_ATTR(in1_input_highest, S_IRUGO, ina209_show_value, NULL,
+                         INA209_BUS_VOLTAGE_MAX_PEAK);
+static SENSOR_DEVICE_ATTR(in1_input_lowest, S_IRUGO, ina209_show_value, NULL,
+                         INA209_BUS_VOLTAGE_MIN_PEAK);
+static SENSOR_DEVICE_ATTR(in1_reset_history, S_IWUSR, NULL,
+                         ina209_reset_history, (1 << 2) | (1 << 3));
+static SENSOR_DEVICE_ATTR(in1_max, S_IRUGO | S_IWUSR, ina209_show_value,
+                         ina209_set_value, INA209_BUS_VOLTAGE_OVER_WARN);
+static SENSOR_DEVICE_ATTR(in1_min, S_IRUGO | S_IWUSR, ina209_show_value,
+                         ina209_set_value, INA209_BUS_VOLTAGE_UNDER_WARN);
+static SENSOR_DEVICE_ATTR(in1_crit_max, S_IRUGO | S_IWUSR, ina209_show_value,
+                         ina209_set_value, INA209_BUS_VOLTAGE_OVER_LIMIT);
+static SENSOR_DEVICE_ATTR(in1_crit_min, S_IRUGO | S_IWUSR, ina209_show_value,
+                         ina209_set_value, INA209_BUS_VOLTAGE_UNDER_LIMIT);
+
+static SENSOR_DEVICE_ATTR(in1_min_alarm, S_IRUGO, ina209_show_alarm, NULL,
+                         1 << 14);
+static SENSOR_DEVICE_ATTR(in1_max_alarm, S_IRUGO, ina209_show_alarm, NULL,
+                         1 << 15);
+static SENSOR_DEVICE_ATTR(in1_crit_min_alarm, S_IRUGO, ina209_show_alarm, NULL,
+                         1 << 9);
+static SENSOR_DEVICE_ATTR(in1_crit_max_alarm, S_IRUGO, ina209_show_alarm, NULL,
+                         1 << 10);
+
+/* Power */
+static SENSOR_DEVICE_ATTR(power1_input, S_IRUGO, ina209_show_value, NULL,
+                         INA209_POWER);
+static SENSOR_DEVICE_ATTR(power1_input_highest, S_IRUGO, ina209_show_value,
+                         NULL, INA209_POWER_PEAK);
+static SENSOR_DEVICE_ATTR(power1_reset_history, S_IWUSR, NULL,
+                         ina209_reset_history, 1 << 4);
+static SENSOR_DEVICE_ATTR(power1_max, S_IRUGO | S_IWUSR, ina209_show_value,
+                         ina209_set_value, INA209_POWER_WARN);
+static SENSOR_DEVICE_ATTR(power1_crit, S_IRUGO | S_IWUSR, ina209_show_value,
+                         ina209_set_value, INA209_POWER_OVER_LIMIT);
+
+static SENSOR_DEVICE_ATTR(power1_max_alarm, S_IRUGO, ina209_show_alarm, NULL,
+                         1 << 13);
+static SENSOR_DEVICE_ATTR(power1_crit_alarm, S_IRUGO, ina209_show_alarm, NULL,
+                         1 << 8);
+
+/* Current */
+static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO, ina209_show_value, NULL,
+                         INA209_CURRENT);
+
+static SENSOR_DEVICE_ATTR(update_interval, S_IRUGO | S_IWUSR,
+                         ina209_show_interval, ina209_set_interval, 0);
+
+/*
+ * Finally, construct an array of pointers to members of the above objects,
+ * as required for sysfs_create_group()
+ */
+static struct attribute *ina209_attributes[] = {
+       &sensor_dev_attr_in0_input.dev_attr.attr,
+       &sensor_dev_attr_in0_input_highest.dev_attr.attr,
+       &sensor_dev_attr_in0_input_lowest.dev_attr.attr,
+       &sensor_dev_attr_in0_reset_history.dev_attr.attr,
+       &sensor_dev_attr_in0_max.dev_attr.attr,
+       &sensor_dev_attr_in0_min.dev_attr.attr,
+       &sensor_dev_attr_in0_crit_max.dev_attr.attr,
+       &sensor_dev_attr_in0_crit_min.dev_attr.attr,
+       &sensor_dev_attr_in0_max_alarm.dev_attr.attr,
+       &sensor_dev_attr_in0_min_alarm.dev_attr.attr,
+       &sensor_dev_attr_in0_crit_max_alarm.dev_attr.attr,
+       &sensor_dev_attr_in0_crit_min_alarm.dev_attr.attr,
+
+       &sensor_dev_attr_in1_input.dev_attr.attr,
+       &sensor_dev_attr_in1_input_highest.dev_attr.attr,
+       &sensor_dev_attr_in1_input_lowest.dev_attr.attr,
+       &sensor_dev_attr_in1_reset_history.dev_attr.attr,
+       &sensor_dev_attr_in1_max.dev_attr.attr,
+       &sensor_dev_attr_in1_min.dev_attr.attr,
+       &sensor_dev_attr_in1_crit_max.dev_attr.attr,
+       &sensor_dev_attr_in1_crit_min.dev_attr.attr,
+       &sensor_dev_attr_in1_max_alarm.dev_attr.attr,
+       &sensor_dev_attr_in1_min_alarm.dev_attr.attr,
+       &sensor_dev_attr_in1_crit_max_alarm.dev_attr.attr,
+       &sensor_dev_attr_in1_crit_min_alarm.dev_attr.attr,
+
+       &sensor_dev_attr_power1_input.dev_attr.attr,
+       &sensor_dev_attr_power1_input_highest.dev_attr.attr,
+       &sensor_dev_attr_power1_reset_history.dev_attr.attr,
+       &sensor_dev_attr_power1_max.dev_attr.attr,
+       &sensor_dev_attr_power1_crit.dev_attr.attr,
+       &sensor_dev_attr_power1_max_alarm.dev_attr.attr,
+       &sensor_dev_attr_power1_crit_alarm.dev_attr.attr,
+
+       &sensor_dev_attr_curr1_input.dev_attr.attr,
+
+       &sensor_dev_attr_update_interval.dev_attr.attr,
+
+       NULL,
+};
+
+static const struct attribute_group ina209_group = {
+       .attrs = ina209_attributes,
+};
+
+static void ina209_restore_conf(struct i2c_client *client,
+                               struct ina209_data *data)
+{
+       /* Restore initial configuration */
+       i2c_smbus_write_word_swapped(client, INA209_CONFIGURATION,
+                                    data->config_orig);
+       i2c_smbus_write_word_swapped(client, INA209_CALIBRATION,
+                                    data->calibration_orig);
+}
+
+static int ina209_init_client(struct i2c_client *client,
+                             struct ina209_data *data)
+{
+       struct ina2xx_platform_data *pdata = dev_get_platdata(&client->dev);
+       u32 shunt;
+       int reg;
+
+       reg = i2c_smbus_read_word_swapped(client, INA209_CALIBRATION);
+       if (reg < 0)
+               return reg;
+       data->calibration_orig = reg;
+
+       reg = i2c_smbus_read_word_swapped(client, INA209_CONFIGURATION);
+       if (reg < 0)
+               return reg;
+       data->config_orig = reg;
+
+       if (pdata) {
+               if (pdata->shunt_uohms <= 0)
+                       return -EINVAL;
+               shunt = pdata->shunt_uohms;
+       } else if (!of_property_read_u32(client->dev.of_node, "shunt-resistor",
+                                        &shunt)) {
+               if (shunt == 0)
+                       return -EINVAL;
+       } else {
+               shunt = data->calibration_orig ?
+                 40960000 / data->calibration_orig : INA209_SHUNT_DEFAULT;
+       }
+
+       i2c_smbus_write_word_swapped(client, INA209_CONFIGURATION,
+                                    INA209_CONFIG_DEFAULT);
+       data->update_interval = ina209_interval_from_reg(INA209_CONFIG_DEFAULT);
+
+       /*
+        * Calibrate current LSB to 1mA. Shunt is in uOhms.
+        * See equation 13 in datasheet.
+        */
+       i2c_smbus_write_word_swapped(client, INA209_CALIBRATION,
+                                    clamp_val(40960000 / shunt, 1, 65535));
+
+       /* Clear status register */
+       i2c_smbus_read_word_swapped(client, INA209_STATUS);
+
+       return 0;
+}
+
+static int ina209_probe(struct i2c_client *client,
+                       const struct i2c_device_id *id)
+{
+       struct i2c_adapter *adapter = client->adapter;
+       struct ina209_data *data;
+       int ret;
+
+       if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA))
+               return -ENODEV;
+
+       data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
+       if (!data)
+               return -ENOMEM;
+
+       i2c_set_clientdata(client, data);
+       mutex_init(&data->update_lock);
+
+       ret = ina209_init_client(client, data);
+       if (ret)
+               return ret;
+
+       /* Register sysfs hooks */
+       ret = sysfs_create_group(&client->dev.kobj, &ina209_group);
+       if (ret)
+               goto out_restore_conf;
+
+       data->hwmon_dev = hwmon_device_register(&client->dev);
+       if (IS_ERR(data->hwmon_dev)) {
+               ret = PTR_ERR(data->hwmon_dev);
+               goto out_hwmon_device_register;
+       }
+
+       return 0;
+
+out_hwmon_device_register:
+       sysfs_remove_group(&client->dev.kobj, &ina209_group);
+out_restore_conf:
+       ina209_restore_conf(client, data);
+       return ret;
+}
+
+static int ina209_remove(struct i2c_client *client)
+{
+       struct ina209_data *data = i2c_get_clientdata(client);
+
+       hwmon_device_unregister(data->hwmon_dev);
+       sysfs_remove_group(&client->dev.kobj, &ina209_group);
+       ina209_restore_conf(client, data);
+
+       return 0;
+}
+
+static const struct i2c_device_id ina209_id[] = {
+       { "ina209", 0 },
+       { }
+};
+MODULE_DEVICE_TABLE(i2c, ina209_id);
+
+/* This is the driver that will be inserted */
+static struct i2c_driver ina209_driver = {
+       .class          = I2C_CLASS_HWMON,
+       .driver = {
+               .name   = "ina209",
+       },
+       .probe          = ina209_probe,
+       .remove         = ina209_remove,
+       .id_table       = ina209_id,
+};
+
+module_i2c_driver(ina209_driver);
+
+MODULE_AUTHOR("Ira W. Snyder <iws@ovro.caltech.edu>, Paul Hays <Paul.Hays@cattail.ca>, Guenter Roeck <linux@roeck-us.net>");
+MODULE_DESCRIPTION("INA209 driver");
+MODULE_LICENSE("GPL");