diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 8a91c99..bc6810c 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -571,6 +571,17 @@
 	  This driver can also be built as a module.  If so, the module
 	  will be called lm93.
 
+config SENSORS_LTC4215
+	tristate "Linear Technology LTC4215"
+	depends on I2C && EXPERIMENTAL
+	default n
+	help
+	  If you say yes here you get support for Linear Technology LTC4215
+	  Hot Swap Controller I2C interface.
+
+	  This driver can also be built as a module. If so, the module will
+	  be called ltc4215.
+
 config SENSORS_LTC4245
 	tristate "Linear Technology LTC4245"
 	depends on I2C && EXPERIMENTAL
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index 81c8882..4da261d 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -65,6 +65,7 @@
 obj-$(CONFIG_SENSORS_LM92)	+= lm92.o
 obj-$(CONFIG_SENSORS_LM93)	+= lm93.o
 obj-$(CONFIG_SENSORS_LM95241)	+= lm95241.o
+obj-$(CONFIG_SENSORS_LTC4215)	+= ltc4215.o
 obj-$(CONFIG_SENSORS_LTC4245)	+= ltc4245.o
 obj-$(CONFIG_SENSORS_MAX1111)	+= max1111.o
 obj-$(CONFIG_SENSORS_MAX1619)	+= max1619.o
diff --git a/drivers/hwmon/ltc4215.c b/drivers/hwmon/ltc4215.c
new file mode 100644
index 0000000..9386e2a
--- /dev/null
+++ b/drivers/hwmon/ltc4215.c
@@ -0,0 +1,364 @@
+/*
+ * Driver for Linear Technology LTC4215 I2C Hot Swap Controller
+ *
+ * Copyright (C) 2009 Ira W. Snyder <iws@ovro.caltech.edu>
+ *
+ * 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.linear.com/pc/downloadDocument.do?navId=H0,C1,C1003,C1006,C1163,P17572,D12697
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+
+static const unsigned short normal_i2c[] = { I2C_CLIENT_END };
+
+/* Insmod parameters */
+I2C_CLIENT_INSMOD_1(ltc4215);
+
+/* Here are names of the chip's registers (a.k.a. commands) */
+enum ltc4215_cmd {
+	LTC4215_CONTROL			= 0x00, /* rw */
+	LTC4215_ALERT			= 0x01, /* rw */
+	LTC4215_STATUS			= 0x02, /* ro */
+	LTC4215_FAULT			= 0x03, /* rw */
+	LTC4215_SENSE			= 0x04, /* rw */
+	LTC4215_SOURCE			= 0x05, /* rw */
+	LTC4215_ADIN			= 0x06, /* rw */
+};
+
+struct ltc4215_data {
+	struct device *hwmon_dev;
+
+	struct mutex update_lock;
+	bool valid;
+	unsigned long last_updated; /* in jiffies */
+
+	/* Registers */
+	u8 regs[7];
+};
+
+static struct ltc4215_data *ltc4215_update_device(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct ltc4215_data *data = i2c_get_clientdata(client);
+	s32 val;
+	int i;
+
+	mutex_lock(&data->update_lock);
+
+	/* The chip's A/D updates 10 times per second */
+	if (time_after(jiffies, data->last_updated + HZ / 10) || !data->valid) {
+
+		dev_dbg(&client->dev, "Starting ltc4215 update\n");
+
+		/* Read all registers */
+		for (i = 0; i < ARRAY_SIZE(data->regs); i++) {
+			val = i2c_smbus_read_byte_data(client, i);
+			if (unlikely(val < 0))
+				data->regs[i] = 0;
+			else
+				data->regs[i] = val;
+		}
+
+		data->last_updated = jiffies;
+		data->valid = 1;
+	}
+
+	mutex_unlock(&data->update_lock);
+
+	return data;
+}
+
+/* Return the voltage from the given register in millivolts */
+static int ltc4215_get_voltage(struct device *dev, u8 reg)
+{
+	struct ltc4215_data *data = ltc4215_update_device(dev);
+	const u8 regval = data->regs[reg];
+	u32 voltage = 0;
+
+	switch (reg) {
+	case LTC4215_SENSE:
+		/* 151 uV per increment */
+		voltage = regval * 151 / 1000;
+		break;
+	case LTC4215_SOURCE:
+		/* 60.5 mV per increment */
+		voltage = regval * 605 / 10;
+		break;
+	case LTC4215_ADIN:
+		/* The ADIN input is divided by 12.5, and has 4.82 mV
+		 * per increment, so we have the additional multiply */
+		voltage = regval * 482 * 125 / 1000;
+		break;
+	default:
+		/* If we get here, the developer messed up */
+		WARN_ON_ONCE(1);
+		break;
+	}
+
+	return voltage;
+}
+
+/* Return the current from the sense resistor in mA */
+static unsigned int ltc4215_get_current(struct device *dev)
+{
+	struct ltc4215_data *data = ltc4215_update_device(dev);
+
+	/* The strange looking conversions that follow are fixed-point
+	 * math, since we cannot do floating point in the kernel.
+	 *
+	 * Step 1: convert sense register to microVolts
+	 * Step 2: convert voltage to milliAmperes
+	 *
+	 * If you play around with the V=IR equation, you come up with
+	 * the following: X uV / Y mOhm == Z mA
+	 *
+	 * With the resistors that are fractions of a milliOhm, we multiply
+	 * the voltage and resistance by 10, to shift the decimal point.
+	 * Now we can use the normal division operator again.
+	 */
+
+	/* Calculate voltage in microVolts (151 uV per increment) */
+	const unsigned int voltage = data->regs[LTC4215_SENSE] * 151;
+
+	/* Calculate current in milliAmperes (4 milliOhm sense resistor) */
+	const unsigned int curr = voltage / 4;
+
+	return curr;
+}
+
+static ssize_t ltc4215_show_voltage(struct device *dev,
+				    struct device_attribute *da,
+				    char *buf)
+{
+	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+	const int voltage = ltc4215_get_voltage(dev, attr->index);
+
+	return snprintf(buf, PAGE_SIZE, "%d\n", voltage);
+}
+
+static ssize_t ltc4215_show_current(struct device *dev,
+				    struct device_attribute *da,
+				    char *buf)
+{
+	const unsigned int curr = ltc4215_get_current(dev);
+
+	return snprintf(buf, PAGE_SIZE, "%u\n", curr);
+}
+
+static ssize_t ltc4215_show_power(struct device *dev,
+				  struct device_attribute *da,
+				  char *buf)
+{
+	const unsigned int curr = ltc4215_get_current(dev);
+	const int output_voltage = ltc4215_get_voltage(dev, LTC4215_ADIN);
+
+	/* current in mA * voltage in mV == power in uW */
+	const unsigned int power = abs(output_voltage * curr);
+
+	return snprintf(buf, PAGE_SIZE, "%u\n", power);
+}
+
+static ssize_t ltc4215_show_alarm(struct device *dev,
+					  struct device_attribute *da,
+					  char *buf)
+{
+	struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(da);
+	struct ltc4215_data *data = ltc4215_update_device(dev);
+	const u8 reg = data->regs[attr->index];
+	const u32 mask = attr->nr;
+
+	return snprintf(buf, PAGE_SIZE, "%u\n", (reg & mask) ? 1 : 0);
+}
+
+/* These macros are used below in constructing device attribute objects
+ * for use with sysfs_create_group() to make a sysfs device file
+ * for each register.
+ */
+
+#define LTC4215_VOLTAGE(name, ltc4215_cmd_idx) \
+	static SENSOR_DEVICE_ATTR(name, S_IRUGO, \
+	ltc4215_show_voltage, NULL, ltc4215_cmd_idx)
+
+#define LTC4215_CURRENT(name) \
+	static SENSOR_DEVICE_ATTR(name, S_IRUGO, \
+	ltc4215_show_current, NULL, 0);
+
+#define LTC4215_POWER(name) \
+	static SENSOR_DEVICE_ATTR(name, S_IRUGO, \
+	ltc4215_show_power, NULL, 0);
+
+#define LTC4215_ALARM(name, mask, reg) \
+	static SENSOR_DEVICE_ATTR_2(name, S_IRUGO, \
+	ltc4215_show_alarm, NULL, (mask), reg)
+
+/* Construct a sensor_device_attribute structure for each register */
+
+/* Current */
+LTC4215_CURRENT(curr1_input);
+LTC4215_ALARM(curr1_max_alarm,	(1 << 2),	LTC4215_STATUS);
+
+/* Power (virtual) */
+LTC4215_POWER(power1_input);
+LTC4215_ALARM(power1_alarm,	(1 << 3),	LTC4215_STATUS);
+
+/* Input Voltage */
+LTC4215_VOLTAGE(in1_input,			LTC4215_ADIN);
+LTC4215_ALARM(in1_max_alarm,	(1 << 0),	LTC4215_STATUS);
+LTC4215_ALARM(in1_min_alarm,	(1 << 1),	LTC4215_STATUS);
+
+/* Output Voltage */
+LTC4215_VOLTAGE(in2_input,			LTC4215_SOURCE);
+
+/* Finally, construct an array of pointers to members of the above objects,
+ * as required for sysfs_create_group()
+ */
+static struct attribute *ltc4215_attributes[] = {
+	&sensor_dev_attr_curr1_input.dev_attr.attr,
+	&sensor_dev_attr_curr1_max_alarm.dev_attr.attr,
+
+	&sensor_dev_attr_power1_input.dev_attr.attr,
+	&sensor_dev_attr_power1_alarm.dev_attr.attr,
+
+	&sensor_dev_attr_in1_input.dev_attr.attr,
+	&sensor_dev_attr_in1_max_alarm.dev_attr.attr,
+	&sensor_dev_attr_in1_min_alarm.dev_attr.attr,
+
+	&sensor_dev_attr_in2_input.dev_attr.attr,
+
+	NULL,
+};
+
+static const struct attribute_group ltc4215_group = {
+	.attrs = ltc4215_attributes,
+};
+
+static int ltc4215_probe(struct i2c_client *client,
+			 const struct i2c_device_id *id)
+{
+	struct ltc4215_data *data;
+	int ret;
+
+	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	if (!data) {
+		ret = -ENOMEM;
+		goto out_kzalloc;
+	}
+
+	i2c_set_clientdata(client, data);
+	mutex_init(&data->update_lock);
+
+	/* Initialize the LTC4215 chip */
+	/* TODO */
+
+	/* Register sysfs hooks */
+	ret = sysfs_create_group(&client->dev.kobj, &ltc4215_group);
+	if (ret)
+		goto out_sysfs_create_group;
+
+	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, &ltc4215_group);
+out_sysfs_create_group:
+	kfree(data);
+out_kzalloc:
+	return ret;
+}
+
+static int ltc4215_remove(struct i2c_client *client)
+{
+	struct ltc4215_data *data = i2c_get_clientdata(client);
+
+	hwmon_device_unregister(data->hwmon_dev);
+	sysfs_remove_group(&client->dev.kobj, &ltc4215_group);
+
+	kfree(data);
+
+	return 0;
+}
+
+static int ltc4215_detect(struct i2c_client *client,
+			  int kind,
+			  struct i2c_board_info *info)
+{
+	struct i2c_adapter *adapter = client->adapter;
+
+	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
+		return -ENODEV;
+
+	if (kind < 0) {		/* probed detection - check the chip type */
+		s32 v;		/* 8 bits from the chip, or -ERRNO */
+
+		/*
+		 * Register 0x01 bit b7 is reserved, expect 0
+		 * Register 0x03 bit b6 and b7 are reserved, expect 0
+		 */
+		v = i2c_smbus_read_byte_data(client, LTC4215_ALERT);
+		if (v < 0 || (v & (1 << 7)) != 0)
+			return -ENODEV;
+
+		v = i2c_smbus_read_byte_data(client, LTC4215_FAULT);
+		if (v < 0 || (v & ((1 << 6) | (1 << 7))) != 0)
+				return -ENODEV;
+	}
+
+	strlcpy(info->type, "ltc4215", I2C_NAME_SIZE);
+	dev_info(&adapter->dev, "ltc4215 %s at address 0x%02x\n",
+			kind < 0 ? "probed" : "forced",
+			client->addr);
+
+	return 0;
+}
+
+static const struct i2c_device_id ltc4215_id[] = {
+	{ "ltc4215", ltc4215 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, ltc4215_id);
+
+/* This is the driver that will be inserted */
+static struct i2c_driver ltc4215_driver = {
+	.class		= I2C_CLASS_HWMON,
+	.driver = {
+		.name	= "ltc4215",
+	},
+	.probe		= ltc4215_probe,
+	.remove		= ltc4215_remove,
+	.id_table	= ltc4215_id,
+	.detect		= ltc4215_detect,
+	.address_data	= &addr_data,
+};
+
+static int __init ltc4215_init(void)
+{
+	return i2c_add_driver(&ltc4215_driver);
+}
+
+static void __exit ltc4215_exit(void)
+{
+	i2c_del_driver(&ltc4215_driver);
+}
+
+MODULE_AUTHOR("Ira W. Snyder <iws@ovro.caltech.edu>");
+MODULE_DESCRIPTION("LTC4215 driver");
+MODULE_LICENSE("GPL");
+
+module_init(ltc4215_init);
+module_exit(ltc4215_exit);