[PATCH] I2C: add new hardware monitor driver: adm9240

Completion of Michiel Rook's port of adm9240 to 2.6 with addition
of auto fan clock divider based on Jean Delvare's algorithm, and
replaces scaling macros with static inlines.

Signed-off-by: Grant Coady <gcoady@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 768 insertions, 0 deletions

diff --git a/drivers/i2c/chips/adm9240.c b/drivers/i2c/chips/adm9240.c
new file mode 100644
index 000000000000..0b67eab15d2d
--- /dev/null
+++ b/drivers/i2c/chips/adm9240.c
@@ -0,0 +1,768 @@
+/*
+ * adm9240.c	Part of lm_sensors, Linux kernel modules for hardware
+ * 		monitoring
+ *
+ * Copyright (C) 1999	Frodo Looijaard <frodol@dds.nl>
+ *			Philip Edelbrock <phil@netroedge.com>
+ * Copyright (C) 2003	Michiel Rook <michiel@grendelproject.nl>
+ * Copyright (C) 2005	Grant Coady <gcoady@gmail.com> with valuable
+ * 				guidance from Jean Delvare
+ *
+ * Driver supports	Analog Devices		ADM9240
+ *			Dallas Semiconductor	DS1780
+ *			National Semiconductor	LM81
+ *
+ * ADM9240 is the reference, DS1780 and LM81 are register compatibles
+ *
+ * Voltage	Six inputs are scaled by chip, VID also reported
+ * Temperature	Chip temperature to 0.5'C, maximum and max_hysteris
+ * Fans		2 fans, low speed alarm, automatic fan clock divider
+ * Alarms	16-bit map of active alarms
+ * Analog Out	0..1250 mV output
+ *
+ * Chassis Intrusion: clear CI latch with 'echo 1 > chassis_clear'
+ *
+ * Test hardware: Intel SE440BX-2 desktop motherboard --Grant
+ *
+ * LM81 extended temp reading not implemented
+ *
+ * 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.
+ *
+ * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/i2c-sensor.h>
+#include <linux/i2c-vid.h>
+
+/* Addresses to scan */
+static unsigned short normal_i2c[] = { 0x2c, 0x2d, 0x2e, 0x2f,
+					I2C_CLIENT_END };
+
+static unsigned int normal_isa[] = { I2C_CLIENT_ISA_END };
+
+/* Insmod parameters */
+SENSORS_INSMOD_3(adm9240, ds1780, lm81);
+
+/* ADM9240 registers */
+#define ADM9240_REG_MAN_ID		0x3e
+#define ADM9240_REG_DIE_REV		0x3f
+#define ADM9240_REG_CONFIG		0x40
+
+#define ADM9240_REG_IN(nr)		(0x20 + (nr))   /* 0..5 */
+#define ADM9240_REG_IN_MAX(nr)		(0x2b + (nr) * 2)
+#define ADM9240_REG_IN_MIN(nr)		(0x2c + (nr) * 2)
+#define ADM9240_REG_FAN(nr)		(0x28 + (nr))   /* 0..1 */
+#define ADM9240_REG_FAN_MIN(nr)		(0x3b + (nr))
+#define ADM9240_REG_INT(nr)		(0x41 + (nr))
+#define ADM9240_REG_INT_MASK(nr)	(0x43 + (nr))
+#define ADM9240_REG_TEMP		0x27
+#define ADM9240_REG_TEMP_HIGH		0x39
+#define ADM9240_REG_TEMP_HYST		0x3a
+#define ADM9240_REG_ANALOG_OUT		0x19
+#define ADM9240_REG_CHASSIS_CLEAR	0x46
+#define ADM9240_REG_VID_FAN_DIV		0x47
+#define ADM9240_REG_I2C_ADDR		0x48
+#define ADM9240_REG_VID4		0x49
+#define ADM9240_REG_TEMP_CONF		0x4b
+
+/* generalised scaling with integer rounding */
+static inline int SCALE(long val, int mul, int div)
+{
+	if (val < 0)
+		return (val * mul - div / 2) / div;
+	else
+		return (val * mul + div / 2) / div;
+}
+
+/* adm9240 internally scales voltage measurements */
+static const u16 nom_mv[] = { 2500, 2700, 3300, 5000, 12000, 2700 };
+
+static inline unsigned int IN_FROM_REG(u8 reg, int n)
+{
+	return SCALE(reg, nom_mv[n], 192);
+}
+
+static inline u8 IN_TO_REG(unsigned long val, int n)
+{
+	return SENSORS_LIMIT(SCALE(val, 192, nom_mv[n]), 0, 255);
+}
+
+/* temperature range: -40..125, 127 disables temperature alarm */
+static inline s8 TEMP_TO_REG(long val)
+{
+	return SENSORS_LIMIT(SCALE(val, 1, 1000), -40, 127);
+}
+
+/* two fans, each with low fan speed limit */
+static inline unsigned int FAN_FROM_REG(u8 reg, u8 div)
+{
+	if (!reg) /* error */
+		return -1;
+
+	if (reg == 255)
+		return 0;
+
+	return SCALE(1350000, 1, reg * div);
+}
+
+/* analog out 0..1250mV */
+static inline u8 AOUT_TO_REG(unsigned long val)
+{
+	return SENSORS_LIMIT(SCALE(val, 255, 1250), 0, 255);
+}
+
+static inline unsigned int AOUT_FROM_REG(u8 reg)
+{
+	return SCALE(reg, 1250, 255);
+}
+
+static int adm9240_attach_adapter(struct i2c_adapter *adapter);
+static int adm9240_detect(struct i2c_adapter *adapter, int address, int kind);
+static void adm9240_init_client(struct i2c_client *client);
+static int adm9240_detach_client(struct i2c_client *client);
+static struct adm9240_data *adm9240_update_device(struct device *dev);
+
+/* driver data */
+static struct i2c_driver adm9240_driver = {
+	.owner		= THIS_MODULE,
+	.name		= "adm9240",
+	.id		= I2C_DRIVERID_ADM9240,
+	.flags		= I2C_DF_NOTIFY,
+	.attach_adapter	= adm9240_attach_adapter,
+	.detach_client	= adm9240_detach_client,
+};
+
+/* per client data */
+struct adm9240_data {
+	enum chips type;
+	struct i2c_client client;
+	struct semaphore update_lock;
+	char valid;
+	unsigned long last_updated_measure;
+	unsigned long last_updated_config;
+
+	u8 in[6];		/* ro	in0_input */
+	u8 in_max[6];		/* rw	in0_max */
+	u8 in_min[6];		/* rw	in0_min */
+	u8 fan[2];		/* ro	fan1_input */
+	u8 fan_min[2];		/* rw	fan1_min */
+	u8 fan_div[2];		/* rw	fan1_div, read-only accessor */
+	s16 temp;		/* ro	temp1_input, 9-bit sign-extended */
+	s8 temp_high;		/* rw	temp1_max */
+	s8 temp_hyst;		/* rw	temp1_max_hyst */
+	u16 alarms;		/* ro	alarms */
+	u8 aout;		/* rw	analog_out */
+	u8 vid;			/* ro	vid */
+	u8 vrm;			/* --	vrm set on startup, no accessor */
+};
+
+/* i2c byte read/write interface */
+static int adm9240_read_value(struct i2c_client *client, u8 reg)
+{
+	return i2c_smbus_read_byte_data(client, reg);
+}
+
+static int adm9240_write_value(struct i2c_client *client, u8 reg, u8 value)
+{
+	return i2c_smbus_write_byte_data(client, reg, value);
+}
+
+/*** sysfs accessors ***/
+
+/* temperature */
+#define show_temp(value, scale)					\
+static ssize_t show_##value(struct device *dev, char *buf)	\
+{								\
+	struct adm9240_data *data = adm9240_update_device(dev);	\
+	return sprintf(buf, "%d\n", data->value * scale);	\
+}
+show_temp(temp_high, 1000);
+show_temp(temp_hyst, 1000);
+show_temp(temp, 500);
+
+#define set_temp(value, reg)					\
+static ssize_t set_##value(struct device *dev, const char *buf,	\
+		size_t count)					\
+{								\
+	struct i2c_client *client = to_i2c_client(dev);		\
+	struct adm9240_data *data = adm9240_update_device(dev);	\
+	long temp = simple_strtoul(buf, NULL, 10);		\
+								\
+	down(&data->update_lock);				\
+	data->value = TEMP_TO_REG(temp);			\
+	adm9240_write_value(client, reg, data->value);		\
+	up(&data->update_lock);					\
+	return count;						\
+}
+
+set_temp(temp_high, ADM9240_REG_TEMP_HIGH);
+set_temp(temp_hyst, ADM9240_REG_TEMP_HYST);
+
+static DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,
+		show_temp_high, set_temp_high);
+static DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO,
+		show_temp_hyst, set_temp_hyst);
+static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL);
+
+/* voltage */
+static ssize_t show_in(struct device *dev, char *buf, int nr)
+{
+	struct adm9240_data *data = adm9240_update_device(dev);
+	return sprintf(buf, "%d\n", IN_FROM_REG(data->in[nr], nr));
+}
+
+static ssize_t show_in_min(struct device *dev, char *buf, int nr)
+{
+	struct adm9240_data *data = adm9240_update_device(dev);
+	return sprintf(buf, "%d\n", IN_FROM_REG(data->in_min[nr], nr));
+}
+
+static ssize_t show_in_max(struct device *dev, char *buf, int nr)
+{
+	struct adm9240_data *data = adm9240_update_device(dev);
+	return sprintf(buf, "%d\n", IN_FROM_REG(data->in_max[nr], nr));
+}
+
+static ssize_t set_in_min(struct device *dev, const char *buf,
+		size_t count, int nr)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct adm9240_data *data = i2c_get_clientdata(client);
+	unsigned long val = simple_strtoul(buf, NULL, 10);
+
+	down(&data->update_lock);
+	data->in_min[nr] = IN_TO_REG(val, nr);
+	adm9240_write_value(client, ADM9240_REG_IN_MIN(nr), data->in_min[nr]);
+	up(&data->update_lock);
+	return count;
+}
+
+static ssize_t set_in_max(struct device *dev, const char *buf,
+		size_t count, int nr)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct adm9240_data *data = i2c_get_clientdata(client);
+	unsigned long val = simple_strtoul(buf, NULL, 10);
+
+	down(&data->update_lock);
+	data->in_max[nr] = IN_TO_REG(val, nr);
+	adm9240_write_value(client, ADM9240_REG_IN_MAX(nr), data->in_max[nr]);
+	up(&data->update_lock);
+	return count;
+}
+
+#define show_in_offset(offset)						\
+static ssize_t show_in##offset(struct device *dev, char *buf)		\
+{									\
+	return show_in(dev, buf, offset);				\
+}									\
+static DEVICE_ATTR(in##offset##_input, S_IRUGO, show_in##offset, NULL);	\
+static ssize_t show_in##offset##_min(struct device *dev, char *buf)	\
+{									\
+	return show_in_min(dev, buf, offset);				\
+}									\
+static ssize_t show_in##offset##_max(struct device *dev, char *buf)	\
+{									\
+	return show_in_max(dev, buf, offset);				\
+}									\
+static ssize_t								\
+set_in##offset##_min(struct device *dev, const char *buf, size_t count)	\
+{									\
+	return set_in_min(dev, buf, count, offset);			\
+}									\
+static ssize_t								\
+set_in##offset##_max(struct device *dev, const char *buf, size_t count)	\
+{									\
+	return set_in_max(dev, buf, count, offset);			\
+}									\
+static DEVICE_ATTR(in##offset##_min, S_IRUGO | S_IWUSR,			\
+		show_in##offset##_min, set_in##offset##_min);		\
+static DEVICE_ATTR(in##offset##_max, S_IRUGO | S_IWUSR,			\
+		show_in##offset##_max, set_in##offset##_max);
+
+show_in_offset(0);
+show_in_offset(1);
+show_in_offset(2);
+show_in_offset(3);
+show_in_offset(4);
+show_in_offset(5);
+
+/* fans */
+static ssize_t show_fan(struct device *dev, char *buf, int nr)
+{
+	struct adm9240_data *data = adm9240_update_device(dev);
+	return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan[nr],
+				1 << data->fan_div[nr]));
+}
+
+static ssize_t show_fan_min(struct device *dev, char *buf, int nr)
+{
+	struct adm9240_data *data = adm9240_update_device(dev);
+	return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan_min[nr],
+				1 << data->fan_div[nr]));
+}
+
+static ssize_t show_fan_div(struct device *dev, char *buf, int nr)
+{
+	struct adm9240_data *data = adm9240_update_device(dev);
+	return sprintf(buf, "%d\n", 1 << data->fan_div[nr]);
+}
+
+/* write new fan div, callers must hold data->update_lock */
+static void adm9240_write_fan_div(struct i2c_client *client, int nr,
+		u8 fan_div)
+{
+	u8 reg, old, shift = (nr + 2) * 2;
+
+	reg = adm9240_read_value(client, ADM9240_REG_VID_FAN_DIV);
+	old = (reg >> shift) & 3;
+	reg &= ~(3 << shift);
+	reg |= (fan_div << shift);
+	adm9240_write_value(client, ADM9240_REG_VID_FAN_DIV, reg);
+	dev_dbg(&client->dev, "fan%d clock divider changed from %u "
+			"to %u\n", nr + 1, 1 << old, 1 << fan_div);
+}
+
+/* 
+ * set fan speed low limit:
+ *
+ * - value is zero: disable fan speed low limit alarm
+ *
+ * - value is below fan speed measurement range: enable fan speed low
+ *   limit alarm to be asserted while fan speed too slow to measure
+ *
+ * - otherwise: select fan clock divider to suit fan speed low limit,
+ *   measurement code may adjust registers to ensure fan speed reading
+ */
+static ssize_t set_fan_min(struct device *dev, const char *buf,
+		size_t count, int nr)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct adm9240_data *data = i2c_get_clientdata(client);
+	unsigned long val = simple_strtoul(buf, NULL, 10);
+	u8 new_div;
+
+	down(&data->update_lock);
+
+	if (!val) {
+		data->fan_min[nr] = 255;
+		new_div = data->fan_div[nr];
+
+		dev_dbg(&client->dev, "fan%u low limit set disabled\n",
+				nr + 1);
+
+	} else if (val < 1350000 / (8 * 254)) {
+		new_div = 3;
+		data->fan_min[nr] = 254;
+
+		dev_dbg(&client->dev, "fan%u low limit set minimum %u\n",
+				nr + 1, FAN_FROM_REG(254, 1 << new_div));
+
+	} else {
+		unsigned int new_min = 1350000 / val;
+
+		new_div = 0;
+		while (new_min > 192 && new_div < 3) {
+			new_div++;
+			new_min /= 2;
+		}
+		if (!new_min) /* keep > 0 */
+			new_min++;
+
+		data->fan_min[nr] = new_min;
+
+		dev_dbg(&client->dev, "fan%u low limit set fan speed %u\n",
+				nr + 1, FAN_FROM_REG(new_min, 1 << new_div));
+	}
+
+	if (new_div != data->fan_div[nr]) {
+		data->fan_div[nr] = new_div;
+		adm9240_write_fan_div(client, nr, new_div);
+	}
+	adm9240_write_value(client, ADM9240_REG_FAN_MIN(nr),
+			data->fan_min[nr]);
+
+	up(&data->update_lock);
+	return count;
+}
+
+#define show_fan_offset(offset)						\
+static ssize_t show_fan_##offset (struct device *dev, char *buf)	\
+{									\
+return show_fan(dev, buf, offset - 1);					\
+}									\
+static ssize_t show_fan_##offset##_div (struct device *dev, char *buf)	\
+{									\
+return show_fan_div(dev, buf, offset - 1);				\
+}									\
+static ssize_t show_fan_##offset##_min (struct device *dev, char *buf)	\
+{									\
+return show_fan_min(dev, buf, offset - 1);				\
+}									\
+static ssize_t set_fan_##offset##_min (struct device *dev, 		\
+const char *buf, size_t count)						\
+{									\
+return set_fan_min(dev, buf, count, offset - 1);			\
+}									\
+static DEVICE_ATTR(fan##offset##_input, S_IRUGO, 			\
+		show_fan_##offset, NULL);				\
+static DEVICE_ATTR(fan##offset##_div, S_IRUGO, 				\
+		show_fan_##offset##_div, NULL);				\
+static DEVICE_ATTR(fan##offset##_min, S_IRUGO | S_IWUSR, 		\
+		show_fan_##offset##_min, set_fan_##offset##_min);
+
+show_fan_offset(1);
+show_fan_offset(2);
+
+/* alarms */
+static ssize_t show_alarms(struct device *dev, char *buf)
+{
+	struct adm9240_data *data = adm9240_update_device(dev);
+	return sprintf(buf, "%u\n", data->alarms);
+}
+static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
+
+/* vid */
+static ssize_t show_vid(struct device *dev, char *buf)
+{
+	struct adm9240_data *data = adm9240_update_device(dev);
+	return sprintf(buf, "%d\n", vid_from_reg(data->vid, data->vrm));
+}
+static DEVICE_ATTR(cpu0_vid, S_IRUGO, show_vid, NULL);
+
+/* analog output */
+static ssize_t show_aout(struct device *dev, char *buf)
+{
+	struct adm9240_data *data = adm9240_update_device(dev);
+	return sprintf(buf, "%d\n", AOUT_FROM_REG(data->aout));
+}
+
+static ssize_t set_aout(struct device *dev, const char *buf, size_t count)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct adm9240_data *data = i2c_get_clientdata(client);
+	unsigned long val = simple_strtol(buf, NULL, 10);
+
+	down(&data->update_lock);
+	data->aout = AOUT_TO_REG(val);
+	adm9240_write_value(client, ADM9240_REG_ANALOG_OUT, data->aout);
+	up(&data->update_lock);
+	return count;
+}
+static DEVICE_ATTR(aout_output, S_IRUGO | S_IWUSR, show_aout, set_aout);
+
+/* chassis_clear */
+static ssize_t chassis_clear(struct device *dev, const char *buf, size_t count)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	unsigned long val = simple_strtol(buf, NULL, 10);
+
+	if (val == 1) {
+		adm9240_write_value(client, ADM9240_REG_CHASSIS_CLEAR, 0x80);
+		dev_dbg(&client->dev, "chassis intrusion latch cleared\n");
+	}
+	return count;
+}
+static DEVICE_ATTR(chassis_clear, S_IWUSR, NULL, chassis_clear);
+
+
+/*** sensor chip detect and driver install ***/
+
+static int adm9240_detect(struct i2c_adapter *adapter, int address, int kind)
+{
+	struct i2c_client *new_client;
+	struct adm9240_data *data;
+	int err = 0;
+	const char *name = "";
+	u8 man_id, die_rev;
+
+	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
+		goto exit;
+
+	if (!(data = kmalloc(sizeof(struct adm9240_data), GFP_KERNEL))) {
+		err = -ENOMEM;
+		goto exit;
+	}
+	memset(data, 0, sizeof(struct adm9240_data));
+
+	new_client = &data->client;
+	i2c_set_clientdata(new_client, data);
+	new_client->addr = address;
+	new_client->adapter = adapter;
+	new_client->driver = &adm9240_driver;
+	new_client->flags = 0;
+
+	if (kind == 0) {
+		kind = adm9240;
+	}
+
+	if (kind < 0) {
+
+		/* verify chip: reg address should match i2c address */
+		if (adm9240_read_value(new_client, ADM9240_REG_I2C_ADDR)
+				!= address) {
+			dev_err(&adapter->dev, "detect fail: address match, "
+					"0x%02x\n", address);
+			goto exit_free;
+		}
+
+		/* check known chip manufacturer */
+		man_id = adm9240_read_value(new_client, ADM9240_REG_MAN_ID);
+
+		if (man_id == 0x23) {
+			kind = adm9240;
+		} else if (man_id == 0xda) {
+			kind = ds1780;
+		} else if (man_id == 0x01) {
+			kind = lm81;
+		} else {
+			dev_err(&adapter->dev, "detect fail: unknown manuf, "
+					"0x%02x\n", man_id);
+			goto exit_free;
+		}
+
+		/* successful detect, print chip info */
+		die_rev = adm9240_read_value(new_client, ADM9240_REG_DIE_REV);
+		dev_info(&adapter->dev, "found %s revision %u\n",
+				man_id == 0x23 ? "ADM9240" :
+				man_id == 0xda ? "DS1780" : "LM81", die_rev);
+	}
+
+	/* either forced or detected chip kind */
+	if (kind == adm9240) {
+		name = "adm9240";
+	} else if (kind == ds1780) {
+		name = "ds1780";
+	} else if (kind == lm81) {
+		name = "lm81";
+	}
+
+	/* fill in the remaining client fields and attach */
+	strlcpy(new_client->name, name, I2C_NAME_SIZE);
+	data->type = kind;
+	init_MUTEX(&data->update_lock);
+
+	if ((err = i2c_attach_client(new_client)))
+		goto exit_free;
+
+	adm9240_init_client(new_client);
+
+	/* populate sysfs filesystem */
+	device_create_file(&new_client->dev, &dev_attr_in0_input);
+	device_create_file(&new_client->dev, &dev_attr_in0_min);
+	device_create_file(&new_client->dev, &dev_attr_in0_max);
+	device_create_file(&new_client->dev, &dev_attr_in1_input);
+	device_create_file(&new_client->dev, &dev_attr_in1_min);
+	device_create_file(&new_client->dev, &dev_attr_in1_max);
+	device_create_file(&new_client->dev, &dev_attr_in2_input);
+	device_create_file(&new_client->dev, &dev_attr_in2_min);
+	device_create_file(&new_client->dev, &dev_attr_in2_max);
+	device_create_file(&new_client->dev, &dev_attr_in3_input);
+	device_create_file(&new_client->dev, &dev_attr_in3_min);
+	device_create_file(&new_client->dev, &dev_attr_in3_max);
+	device_create_file(&new_client->dev, &dev_attr_in4_input);
+	device_create_file(&new_client->dev, &dev_attr_in4_min);
+	device_create_file(&new_client->dev, &dev_attr_in4_max);
+	device_create_file(&new_client->dev, &dev_attr_in5_input);
+	device_create_file(&new_client->dev, &dev_attr_in5_min);
+	device_create_file(&new_client->dev, &dev_attr_in5_max);
+	device_create_file(&new_client->dev, &dev_attr_temp1_max);
+	device_create_file(&new_client->dev, &dev_attr_temp1_max_hyst);
+	device_create_file(&new_client->dev, &dev_attr_temp1_input);
+	device_create_file(&new_client->dev, &dev_attr_fan1_input);
+	device_create_file(&new_client->dev, &dev_attr_fan1_div);
+	device_create_file(&new_client->dev, &dev_attr_fan1_min);
+	device_create_file(&new_client->dev, &dev_attr_fan2_input);
+	device_create_file(&new_client->dev, &dev_attr_fan2_div);
+	device_create_file(&new_client->dev, &dev_attr_fan2_min);
+	device_create_file(&new_client->dev, &dev_attr_alarms);
+	device_create_file(&new_client->dev, &dev_attr_aout_output);
+	device_create_file(&new_client->dev, &dev_attr_chassis_clear);
+	device_create_file(&new_client->dev, &dev_attr_cpu0_vid);
+
+	return 0;
+exit_free:
+	kfree(new_client);
+exit:
+	return err;
+}
+
+static int adm9240_attach_adapter(struct i2c_adapter *adapter)
+{
+	if (!(adapter->class & I2C_CLASS_HWMON))
+		return 0;
+	return i2c_detect(adapter, &addr_data, adm9240_detect);
+}
+
+static int adm9240_detach_client(struct i2c_client *client)
+{
+	int err;
+
+	if ((err = i2c_detach_client(client))) {
+		dev_err(&client->dev, "Client deregistration failed, "
+				"client not detached.\n");
+		return err;
+	}
+
+	kfree(i2c_get_clientdata(client));
+	return 0;
+}
+
+static void adm9240_init_client(struct i2c_client *client)
+{
+	struct adm9240_data *data = i2c_get_clientdata(client);
+	u8 conf = adm9240_read_value(client, ADM9240_REG_CONFIG);
+	u8 mode = adm9240_read_value(client, ADM9240_REG_TEMP_CONF) & 3;
+
+	data->vrm = i2c_which_vrm(); /* need this to report vid as mV */
+
+	if (conf & 1) { /* measurement cycle running: report state */
+
+		dev_info(&client->dev, "status: config 0x%02x mode %u\n",
+				conf, mode);
+
+	} else { /* cold start: open limits before starting chip */
+		int i;
+
+		for (i = 0; i < 6; i++)
+		{
+			adm9240_write_value(client,
+					ADM9240_REG_IN_MIN(i), 0);
+			adm9240_write_value(client,
+					ADM9240_REG_IN_MAX(i), 255);
+		}
+		adm9240_write_value(client, ADM9240_REG_FAN_MIN(0), 255);
+		adm9240_write_value(client, ADM9240_REG_FAN_MIN(1), 255);
+		adm9240_write_value(client, ADM9240_REG_TEMP_HIGH, 127);
+		adm9240_write_value(client, ADM9240_REG_TEMP_HYST, 127);
+
+		/* start measurement cycle */
+		adm9240_write_value(client, ADM9240_REG_CONFIG, 1);
+
+		dev_info(&client->dev, "cold start: config was 0x%02x "
+				"mode %u\n", conf, mode);
+	}
+}
+
+static struct adm9240_data *adm9240_update_device(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct adm9240_data *data = i2c_get_clientdata(client);
+	int i;
+
+	down(&data->update_lock);
+
+	/* minimum measurement cycle: 1.75 seconds */
+	if (time_after(jiffies, data->last_updated_measure + (HZ * 7 / 4))
+			|| !data->valid) {
+
+		for (i = 0; i < 6; i++) /* read voltages */
+		{
+			data->in[i] = adm9240_read_value(client,
+					ADM9240_REG_IN(i));
+		}
+		data->alarms = adm9240_read_value(client,
+					ADM9240_REG_INT(0)) |
+					adm9240_read_value(client,
+					ADM9240_REG_INT(1)) << 8;
+
+		/* read temperature: assume temperature changes less than
+		 * 0.5'C per two measurement cycles thus ignore possible
+		 * but unlikely aliasing error on lsb reading. --Grant */
+		data->temp = ((adm9240_read_value(client,
+					ADM9240_REG_TEMP) << 8) |
+					adm9240_read_value(client,
+					ADM9240_REG_TEMP_CONF)) / 128;
+
+		for (i = 0; i < 2; i++) /* read fans */
+		{
+			data->fan[i] = adm9240_read_value(client,
+					ADM9240_REG_FAN(i));
+
+			/* adjust fan clock divider on overflow */
+			if (data->valid && data->fan[i] == 255 &&
+					data->fan_div[i] < 3) {
+
+				adm9240_write_fan_div(client, i,
+						++data->fan_div[i]);
+
+				/* adjust fan_min if active, but not to 0 */
+				if (data->fan_min[i] < 255 &&
+						data->fan_min[i] >= 2)
+					data->fan_min[i] /= 2;
+			}
+		}
+		data->last_updated_measure = jiffies;
+	}
+
+	/* minimum config reading cycle: 300 seconds */
+	if (time_after(jiffies, data->last_updated_config + (HZ * 300))
+			|| !data->valid) {
+
+		for (i = 0; i < 6; i++)
+		{
+			data->in_min[i] = adm9240_read_value(client,
+					ADM9240_REG_IN_MIN(i));
+			data->in_max[i] = adm9240_read_value(client,
+					ADM9240_REG_IN_MAX(i));
+		}
+		for (i = 0; i < 2; i++)
+		{
+			data->fan_min[i] = adm9240_read_value(client,
+					ADM9240_REG_FAN_MIN(i));
+		}
+		data->temp_high = adm9240_read_value(client,
+				ADM9240_REG_TEMP_HIGH);
+		data->temp_hyst = adm9240_read_value(client,
+				ADM9240_REG_TEMP_HYST);
+
+		/* read fan divs and 5-bit VID */
+		i = adm9240_read_value(client, ADM9240_REG_VID_FAN_DIV);
+		data->fan_div[0] = (i >> 4) & 3;
+		data->fan_div[1] = (i >> 6) & 3;
+		data->vid = i & 0x0f;
+		data->vid |= (adm9240_read_value(client,
+					ADM9240_REG_VID4) & 1) << 4;
+		/* read analog out */
+		data->aout = adm9240_read_value(client,
+				ADM9240_REG_ANALOG_OUT);
+
+		data->last_updated_config = jiffies;
+		data->valid = 1;
+	}
+	up(&data->update_lock);
+	return data;
+}
+
+static int __init sensors_adm9240_init(void)
+{
+	return i2c_add_driver(&adm9240_driver);
+}
+
+static void __exit sensors_adm9240_exit(void)
+{
+	i2c_del_driver(&adm9240_driver);
+}
+
+MODULE_AUTHOR("Michiel Rook <michiel@grendelproject.nl>, "
+		"Grant Coady <gcoady@gmail.com> and others");
+MODULE_DESCRIPTION("ADM9240/DS1780/LM81 driver");
+MODULE_LICENSE("GPL");
+
+module_init(sensors_adm9240_init);
+module_exit(sensors_adm9240_exit);
+