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authorGuenter Roeck <linux@roeck-us.net>2009-08-20 14:49:25 -0700
committerGuenter Roeck <linux@roeck-us.net>2013-02-06 09:57:59 -0800
commitceeadc5c5187b78ffbea737c7a82ecc1e31e80df (patch)
tree6f506721e61dbc2fd8ed76fb5a69443949869395 /drivers/hwmon/ina209.c
parent2bf9233a108cea32edbb5a65afa8e609fa146577 (diff)
downloadop-kernel-dev-ceeadc5c5187b78ffbea737c7a82ecc1e31e80df.zip
op-kernel-dev-ceeadc5c5187b78ffbea737c7a82ecc1e31e80df.tar.gz
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>
Diffstat (limited to 'drivers/hwmon/ina209.c')
-rw-r--r--drivers/hwmon/ina209.c636
1 files changed, 636 insertions, 0 deletions
diff --git a/drivers/hwmon/ina209.c b/drivers/hwmon/ina209.c
new file mode 100644
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");
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