Signed-off-by: <tomaz.mertelj@guest.arnes.si>

Cc: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Documentation/hwmon/amc6821

+Kernel driver amc6821
+=====================
+
+Supported chips:
+	Prefix: 'amc6821'
+	Addresses scanned: 0x18, 0x19, 0x1a, 0x2c, 0x2d, 0x2e, 0x4c, 0x4d, 0x4e
+	Datasheet: http://focus.ti.com/docs/prod/folders/print/amc6821.html
+
+Authors:
+	Tomaz Mertelj <tomaz.mertelj@guest.arnes.si>
+
+
+Description
+-----------
+
+This driver implements support for the Texas Instruments amc6821 chip.
+The chip has one on-chip and one remote temperature sensor and one pwm fan
+regulator.
+The pwm can be controlled either from software or automatically.
+
+The driver provides the following sensor accesses in sysfs:
+
+temp1_input		ro	on-chip temperature
+temp1_min		rw	"
+temp1_max		rw	"
+temp1_crit	 	rw	"
+temp1_min_alarm		ro	"
+temp1_max_alarm		ro	"
+temp1_crit_alarm	ro	"
+
+temp2_input		ro	remote temperature
+temp2_min		rw	"
+temp2_max		rw	"
+temp2_crit	 	rw	"
+temp2_min_alarm		ro	"
+temp2_max_alarm		ro	"
+temp2_crit_alarm	ro	"
+temp2_fault		ro	"
+
+fan1_input	 	ro	tachometer speed
+fan1_min		rw	"
+fan1_max		rw	"
+fan1_fault	 	ro	"
+fan1_div		rw	Fan divisor can be either 2 or 4.
+
+pwm1			rw	pwm1
+pwm1_enable		rw	regulator mode, 1=open loop, 2=fan controlled
+				by remote temperature, 3=fan controlled by
+				combination of on-chip temperature and
+				remote-sensor temperature,
+pwm1_auto_channels_temp ro	1 if pwm_enable==2, 3 if pwm_enable==3
+pwm1_auto_point1_pwm	ro	Hardwired to 0, shared for both
+				temperature channels.
+pwm1_auto_point2_pwm	rw	This value, shared for both temperature
+				channels.
+pwm1_auto_point3_pwm	rw	Hardwired to 255, shared for both
+				temperature channels.
+
+temp1_auto_point1_temp	ro	Hardwired to temp2_auto_point1_temp
+				which is rw. Below this temperature fan stops.
+temp1_auto_point2_temp	rw	The low-temperature limit of the proportional
+				range. Below this temperature
+				pwm1 = pwm1_auto_point2_pwm. It can go from
+				0 degree C and 124 degree C in steps of
+				4 degree C. Read it out after writing to get
+				actual value.
+temp1_auto_point3_temp	rw	Above this temperature fan runs at maximum
+				speed. It can go from temp1_auto_point2_temp.
+				It can only have certain discrete values
+				which depend on temp1_auto_point2_temp and
+				pwm1_auto_point2_pwm. Read it out after
+				writing to get the actual value.
+
+temp2_auto_point1_temp	rw	Must be between 0 degree C and 63 degree C and
+				it defines passive cooling temperature.
+				Below this temperature the fan stops in
+				the closed loop mode.
+temp2_auto_point2_temp	rw	The low-temperature limit of the proportional
+				range. Below this temperature
+				pwm1 = pwm1_auto_point2_pwm. It can go from
+				0 degree C and 124 degree C in steps
+				of 4 degree C.
+
+temp2_auto_point3_temp	rw	Above this temperature fan runs at maximum
+				speed. It can only have certain discrete
+				values which depend on temp2_auto_point2_temp
+				and pwm1_auto_point2_pwm. Read it out after
+				writing to get actual value.
+
+
+Module parameters
+-----------------
+
+If your board has a BIOS that initializes the amc6821 correctly, you should
+load the module with: init=0.
+
+If your board BIOS doesn't initialize the chip, or you want
+different settings, you can set the following parameters:
+init=1,
+pwminv: 0 default pwm output, 1 inverts pwm output.
+

drivers/hwmon/Kconfig

@@ -794,6 +794,16 @@ config SENSORS_ADS7828
 	  This driver can also be built as a module.  If so, the module
 	  will be called ads7828.
 
+config SENSORS_AMC6821
+	tristate "Texas Instruments AMC6821"
+	depends on I2C  && EXPERIMENTAL
+	help
+	  If you say yes here you get support for the Texas Instruments
+	  AMC6821 hardware monitoring chips.
+
+	  This driver can also be build as a module.  If so, the module
+	  will be called amc6821.
+
 config SENSORS_THMC50
 	tristate "Texas Instruments THMC50 / Analog Devices ADM1022"
 	depends on I2C && EXPERIMENTAL

drivers/hwmon/Makefile

@@ -82,6 +82,7 @@ obj-$(CONFIG_SENSORS_SIS5595)	+= sis5595.o
 obj-$(CONFIG_SENSORS_SMSC47B397)+= smsc47b397.o
 obj-$(CONFIG_SENSORS_SMSC47M1)	+= smsc47m1.o
 obj-$(CONFIG_SENSORS_SMSC47M192)+= smsc47m192.o
+obj-$(CONFIG_SENSORS_AMC6821)	+= amc6821.o
 obj-$(CONFIG_SENSORS_THMC50)	+= thmc50.o
 obj-$(CONFIG_SENSORS_TMP401)	+= tmp401.o
 obj-$(CONFIG_SENSORS_TMP421)	+= tmp421.o

drivers/hwmon/amc6821.c

+/*
+	amc6821.c - Part of lm_sensors, Linux kernel modules for hardware
+	monitoring
+	Copyright (C) 2009 T. Mertelj <tomaz.mertelj@guest.arnes.si>
+
+	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/kernel.h>	/* Needed for KERN_INFO */
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/jiffies.h>
+#include <linux/i2c.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/err.h>
+#include <linux/mutex.h>
+
+
+/*
+ * Addresses to scan.
+ */
+
+static const unsigned short normal_i2c[] = {0x18, 0x19, 0x1a, 0x2c, 0x2d, 0x2e,
+	0x4c, 0x4d, 0x4e, I2C_CLIENT_END};
+
+
+
+/*
+ * Insmod parameters
+ */
+
+static int pwminv = 0;	/*Inverted PWM output. */
+module_param(pwminv, int, S_IRUGO);
+
+static int init = 1; /*Power-on initialization.*/
+module_param(init, int, S_IRUGO);
+
+
+I2C_CLIENT_INSMOD_1(amc6821);
+
+#define AMC6821_REG_DEV_ID 0x3D
+#define AMC6821_REG_COMP_ID 0x3E
+#define AMC6821_REG_CONF1 0x00
+#define AMC6821_REG_CONF2 0x01
+#define AMC6821_REG_CONF3 0x3F
+#define AMC6821_REG_CONF4 0x04
+#define AMC6821_REG_STAT1 0x02
+#define AMC6821_REG_STAT2 0x03
+#define AMC6821_REG_TDATA_LOW 0x08
+#define AMC6821_REG_TDATA_HI 0x09
+#define AMC6821_REG_LTEMP_HI 0x0A
+#define AMC6821_REG_RTEMP_HI 0x0B
+#define AMC6821_REG_LTEMP_LIMIT_MIN 0x15
+#define AMC6821_REG_LTEMP_LIMIT_MAX 0x14
+#define AMC6821_REG_RTEMP_LIMIT_MIN 0x19
+#define AMC6821_REG_RTEMP_LIMIT_MAX 0x18
+#define AMC6821_REG_LTEMP_CRIT 0x1B
+#define AMC6821_REG_RTEMP_CRIT 0x1D
+#define AMC6821_REG_PSV_TEMP 0x1C
+#define AMC6821_REG_DCY 0x22
+#define AMC6821_REG_LTEMP_FAN_CTRL 0x24
+#define AMC6821_REG_RTEMP_FAN_CTRL 0x25
+#define AMC6821_REG_DCY_LOW_TEMP 0x21
+
+#define AMC6821_REG_TACH_LLIMITL 0x10
+#define AMC6821_REG_TACH_LLIMITH 0x11
+#define AMC6821_REG_TACH_HLIMITL 0x12
+#define AMC6821_REG_TACH_HLIMITH 0x13
+
+#define AMC6821_CONF1_START 0x01
+#define AMC6821_CONF1_FAN_INT_EN 0x02
+#define AMC6821_CONF1_FANIE 0x04
+#define AMC6821_CONF1_PWMINV 0x08
+#define AMC6821_CONF1_FAN_FAULT_EN 0x10
+#define AMC6821_CONF1_FDRC0 0x20
+#define AMC6821_CONF1_FDRC1 0x40
+#define AMC6821_CONF1_THERMOVIE 0x80
+
+#define AMC6821_CONF2_PWM_EN 0x01
+#define AMC6821_CONF2_TACH_MODE 0x02
+#define AMC6821_CONF2_TACH_EN 0x04
+#define AMC6821_CONF2_RTFIE 0x08
+#define AMC6821_CONF2_LTOIE 0x10
+#define AMC6821_CONF2_RTOIE 0x20
+#define AMC6821_CONF2_PSVIE 0x40
+#define AMC6821_CONF2_RST 0x80
+
+#define AMC6821_CONF3_THERM_FAN_EN 0x80
+#define AMC6821_CONF3_REV_MASK 0x0F
+
+#define AMC6821_CONF4_OVREN 0x10
+#define AMC6821_CONF4_TACH_FAST 0x20
+#define AMC6821_CONF4_PSPR 0x40
+#define AMC6821_CONF4_MODE 0x80
+
+#define AMC6821_STAT1_RPM_ALARM 0x01
+#define AMC6821_STAT1_FANS 0x02
+#define AMC6821_STAT1_RTH 0x04
+#define AMC6821_STAT1_RTL 0x08
+#define AMC6821_STAT1_R_THERM 0x10
+#define AMC6821_STAT1_RTF 0x20
+#define AMC6821_STAT1_LTH 0x40
+#define AMC6821_STAT1_LTL 0x80
+
+#define AMC6821_STAT2_RTC 0x08
+#define AMC6821_STAT2_LTC 0x10
+#define AMC6821_STAT2_LPSV 0x20
+#define AMC6821_STAT2_L_THERM 0x40
+#define AMC6821_STAT2_THERM_IN 0x80
+
+
+static int amc6821_probe(
+		struct i2c_client *client,
+		const struct i2c_device_id *id);
+static int amc6821_detect(
+		struct i2c_client *client,
+		int kind,
+		struct i2c_board_info *info);
+static int amc6821_init_client(struct i2c_client *client);
+static int amc6821_remove(struct i2c_client *client);
+static struct amc6821_data *amc6821_update_device(struct device *dev);
+
+/*
+ * Driver data (common to all clients)
+ */
+
+static const struct i2c_device_id amc6821_id[] = {
+	{ "amc6821", amc6821 },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(i2c, amc6821_id);
+
+static struct i2c_driver amc6821_driver = {
+	.class = I2C_CLASS_HWMON,
+	.driver = {
+		.name	= "amc6821",
+	},
+	.probe = amc6821_probe,
+	.remove = amc6821_remove,
+	.id_table = amc6821_id,
+	.detect = amc6821_detect,
+	.address_data = &addr_data,
+};
+
+
+/*
+ * Client data (each client gets its own)
+  */
+
+struct amc6821_data {
+	struct device *hwmon_dev;
+	struct mutex update_lock;
+	char valid; /* zero until following fields are valid */
+	unsigned long last_updated; /* in jiffies */
+
+	/* register values */
+	int temp1_input;
+	int temp1_min;
+	int temp1_max;
+	int temp1_crit;
+
+	int temp2_input;
+	int temp2_min;
+	int temp2_max;
+	int temp2_crit;
+
+	u16 fan1_input;
+	u16 fan1_min;
+	u16 fan1_max;
+	u8 fan1_div;
+
+	u8 pwm1;
+	u8 temp1_auto_point_temp[3];
+	u8 temp2_auto_point_temp[3];
+	u8 pwm1_auto_point_pwm[3];
+	u8 pwm1_enable;
+	u8 pwm1_auto_channels_temp;
+
+	u8 stat1;
+	u8 stat2;
+};
+
+
+#define get_temp_para(name) \
+static ssize_t get_##name(\
+		struct device *dev,\
+		struct device_attribute *devattr,\
+		char *buf)\
+{\
+	struct amc6821_data *data = amc6821_update_device(dev);\
+	return sprintf(buf, "%d\n", data->name * 1000);\
+}
+
+get_temp_para(temp1_input);
+get_temp_para(temp1_min);
+get_temp_para(temp1_max);
+get_temp_para(temp2_input);
+get_temp_para(temp2_min);
+get_temp_para(temp2_max);
+get_temp_para(temp1_crit);
+get_temp_para(temp2_crit);
+
+#define set_temp_para(name, reg)\
+static ssize_t set_##name(\
+		struct device *dev,\
+		struct device_attribute *attr,\
+		const char *buf,\
+		size_t count)\
+{ \
+	struct i2c_client *client = to_i2c_client(dev); \
+	struct amc6821_data *data = i2c_get_clientdata(client); \
+	int val = simple_strtol(buf, NULL, 10); \
+	\
+	mutex_lock(&data->update_lock); \
+	data->name = SENSORS_LIMIT(val / 1000, -128, 127); \
+	if (i2c_smbus_write_byte_data(client, reg, data->name)) {\
+		dev_err(&client->dev, "Register write error, aborting.\n");\
+		count = -EIO;\
+	} \
+	mutex_unlock(&data->update_lock); \
+	return count; \
+}
+
+set_temp_para(temp1_min, AMC6821_REG_LTEMP_LIMIT_MIN);
+set_temp_para(temp1_max, AMC6821_REG_LTEMP_LIMIT_MAX);
+set_temp_para(temp2_min, AMC6821_REG_RTEMP_LIMIT_MIN);
+set_temp_para(temp2_max, AMC6821_REG_RTEMP_LIMIT_MAX);
+set_temp_para(temp1_crit, AMC6821_REG_LTEMP_CRIT);
+set_temp_para(temp2_crit, AMC6821_REG_RTEMP_CRIT);
+
+#define get_temp_alarm(name, reg, mask)\
+static ssize_t get_##name(\
+	struct device *dev, \
+	struct device_attribute *devattr,\
+	char *buf)\
+{\
+	struct amc6821_data *data = amc6821_update_device(dev);\
+	if (data->reg &  mask)\
+		return sprintf(buf, "1");\
+	else	\
+		return sprintf(buf, "0");\
+} \
+
+get_temp_alarm(temp1_min_alarm, stat1,	AMC6821_STAT1_LTL)
+get_temp_alarm(temp1_max_alarm, stat1, AMC6821_STAT1_LTH)
+get_temp_alarm(temp2_min_alarm, stat1, AMC6821_STAT1_RTL)
+get_temp_alarm(temp2_max_alarm, stat1, AMC6821_STAT1_RTH)
+get_temp_alarm(temp1_crit_alarm, stat2, AMC6821_STAT2_LTC)
+get_temp_alarm(temp2_crit_alarm, stat2, AMC6821_STAT2_RTC)
+
+
+static ssize_t get_temp2_fault(
+		struct device *dev,
+		struct device_attribute *devattr,
+		char *buf)
+{
+	struct amc6821_data *data = amc6821_update_device(dev);
+	if (data->stat1 & AMC6821_STAT1_RTF)
+		return sprintf(buf, "1");
+	else
+		return sprintf(buf, "0");
+}
+
+static ssize_t get_pwm1(
+		struct device *dev,
+		struct device_attribute *devattr,
+		char *buf)
+{
+	struct amc6821_data *data = amc6821_update_device(dev);
+	return sprintf(buf, "%d\n", data->pwm1);
+}
+
+static ssize_t set_pwm1(
+		struct device *dev,
+		struct device_attribute *devattr,
+		const char *buf,
+		size_t count)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct amc6821_data *data = i2c_get_clientdata(client);
+	int val = simple_strtol(buf, NULL, 10);
+
+	mutex_lock(&data->update_lock);
+	data->pwm1 = SENSORS_LIMIT(val , 0, 255);
+	i2c_smbus_write_byte_data(client, AMC6821_REG_DCY, data->pwm1);
+	mutex_unlock(&data->update_lock);
+	return count;
+}
+
+static ssize_t get_pwm1_enable(
+		struct device *dev,
+		struct device_attribute *devattr,
+		char *buf)
+{
+	struct amc6821_data *data = amc6821_update_device(dev);
+	return sprintf(buf, "%d\n", data->pwm1_enable);
+}
+
+static ssize_t set_pwm1_enable(
+		struct device *dev,
+		struct device_attribute *attr,
+		const char *buf,
+		size_t count)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct amc6821_data *data = i2c_get_clientdata(client);
+	int val = simple_strtol(buf, NULL, 10);
+
+	int config = i2c_smbus_read_byte_data(client, AMC6821_REG_CONF1);
+	if (config < 0) {
+			dev_err(&client->dev,
+			"Error reading configuration register, aborting.\n");
+			return -EIO;
+	}
+
+	switch (val) {
+	case 1:
+		config &= ~AMC6821_CONF1_FDRC0;
+		config &= ~AMC6821_CONF1_FDRC1;
+		break;
+	case 2:
+		config &= ~AMC6821_CONF1_FDRC0;
+		config |= AMC6821_CONF1_FDRC1;
+		break;
+	case 3:
+		config |= AMC6821_CONF1_FDRC0;
+		config |= AMC6821_CONF1_FDRC1;
+		break;
+	default:
+		return -EINVAL;
+	}
+	mutex_lock(&data->update_lock);
+	if (i2c_smbus_write_byte_data(client, AMC6821_REG_CONF1, config)) {
+			dev_err(&client->dev,
+			"Configuration register write error, aborting.\n");
+			count = -EIO;
+	}
+	mutex_unlock(&data->update_lock);
+	return count;
+}
+
+
+static ssize_t get_pwm1_auto_channels_temp(
+		struct device *dev,
+		struct device_attribute *devattr,
+		char *buf)
+{
+	struct amc6821_data *data = amc6821_update_device(dev);
+	return sprintf(buf, "%d\n", data->pwm1_auto_channels_temp);
+}
+
+
+#define get_auto_point(name)\
+static ssize_t get_##name(\
+		struct device *dev,\
+		struct device_attribute *devattr,\
+		char *buf)\
+{\
+	int nr = to_sensor_dev_attr(devattr)->index;\
+	struct amc6821_data *data = amc6821_update_device(dev);\
+	return sprintf(buf, "%d\n", data->name[nr] * 1000);\
+}
+
+get_auto_point(temp1_auto_point_temp);
+get_auto_point(temp2_auto_point_temp);
+
+static ssize_t get_pwm1_auto_point_pwm(
+		struct device *dev,
+		struct device_attribute *devattr,
+		char *buf)
+{
+	int nr = to_sensor_dev_attr(devattr)->index;
+	struct amc6821_data *data = amc6821_update_device(dev);
+	return sprintf(buf, "%d\n", data->pwm1_auto_point_pwm[nr]);
+}
+
+
+#define set_temp_auto_point_temp(name, reg)\
+static ssize_t set_##name(\
+		struct device *dev,\
+		struct device_attribute *attr,\
+		const char *buf,\
+		size_t count)\
+{ \
+	struct i2c_client *client = to_i2c_client(dev); \
+	struct amc6821_data *data = amc6821_update_device(dev);\
+	int nr = to_sensor_dev_attr(attr)->index;\
+	int val = simple_strtol(buf, NULL, 10); \
+	u8 tmp;\
+	int dt;\
+	int dpwm;\
+	\
+	mutex_lock(&data->update_lock); \
+	switch (nr) {\
+	case 0:\
+		data->name[0] = SENSORS_LIMIT(val / 1000, 0,\
+				data->temp1_auto_point_temp[1]);\
+		data->name[0] = SENSORS_LIMIT(data->name[0], 0,\
+				data->temp2_auto_point_temp[1]);\
+		data->name[0] = SENSORS_LIMIT(data->name[0], 0, 63); \
+		data->valid = 0;\
+		if (i2c_smbus_write_byte_data(\
+					client,\
+					AMC6821_REG_PSV_TEMP,\
+					data->name[0])) {\
+				dev_err(&client->dev,\
+					"Register write error, aborting.\n");\
+				count = -EIO;\
+		} \
+		goto EXIT;\
+		break;\
+	case 1:\
+		data->name[1] = SENSORS_LIMIT(\
+					val / 1000,\
+					(data->name[0] & 0x7C) + 4,\
+					124);\
+		data->name[1] &= 0x7C;\
+		data->name[2] = SENSORS_LIMIT(\
+					data->name[2], data->name[1] + 1,\
+					255);\
+		break;\
+	case 2:\
+		data->name[2] = SENSORS_LIMIT(\
+					val / 1000,\
+					data->name[1]+1,\
+					255); \
+		break;\
+	} \
+	dt = data->name[2]-data->name[1];\
+	dpwm = data->pwm1_auto_point_pwm[2] - data->pwm1_auto_point_pwm[1];\
+	for (tmp = 4; tmp > 0; tmp--) {\
+		if (dt * (0x20 >> tmp) >= dpwm)\
+			break;\
+	} \
+	tmp |= (data->name[1] & 0x7C) << 1;\
+	if (i2c_smbus_write_byte_data(client, reg, tmp)) {\
+		dev_err(&client->dev, "Register write error, aborting.\n");\
+		count = -EIO;\
+	} \
+	data->valid = 0;\
+EXIT:\
+	mutex_unlock(&data->update_lock); \
+	return count; \
+}
+
+set_temp_auto_point_temp(temp1_auto_point_temp, AMC6821_REG_LTEMP_FAN_CTRL);
+set_temp_auto_point_temp(temp2_auto_point_temp, AMC6821_REG_RTEMP_FAN_CTRL);
+
+static ssize_t set_pwm1_auto_point_pwm(
+		struct device *dev,
+		struct device_attribute *attr,
+		const char *buf,
+		size_t count)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct amc6821_data *data = i2c_get_clientdata(client);
+	int val = simple_strtol(buf, NULL, 10);
+	u8 tmp;
+	int dt;
+	int dpwm;
+
+	mutex_lock(&data->update_lock);
+	data->pwm1_auto_point_pwm[1] = SENSORS_LIMIT(val, 0, 254);
+	if (i2c_smbus_write_byte_data(client, AMC6821_REG_DCY_LOW_TEMP,
+			data->pwm1_auto_point_pwm[1])) {
+		dev_err(&client->dev, "Register write error, aborting.\n");
+		count = -EIO;
+	}
+
+	dpwm = data->pwm1_auto_point_pwm[2] - data->pwm1_auto_point_pwm[1];
+	dt = data->temp1_auto_point_temp[2]-data->temp1_auto_point_temp[1];
+	for (tmp = 4; tmp > 0; tmp--) {
+		if (dt * (0x20 >> tmp) >= dpwm)
+			break;
+	}
+	tmp |= (data->temp1_auto_point_temp[1] & 0x7C) << 1;
+	if (i2c_smbus_write_byte_data(client,
+			AMC6821_REG_LTEMP_FAN_CTRL, tmp)) {
+		dev_err(&client->dev, "Register write error, aborting.\n");
+		count = -EIO;
+	}
+
+	dt = data->temp2_auto_point_temp[2]-data->temp2_auto_point_temp[1];
+	for (tmp = 4; tmp > 0; tmp--) {
+		if (dt * (0x20 >> tmp) >= dpwm)
+			break;
+	}
+	tmp |= (data->temp2_auto_point_temp[1] & 0x7C) << 1;
+	if (i2c_smbus_write_byte_data(client,
+			AMC6821_REG_RTEMP_FAN_CTRL, tmp)) {
+		dev_err(&client->dev, "Register write error, aborting.\n");
+		count = -EIO;
+	}
+	data->valid = 0;
+	mutex_unlock(&data->update_lock);
+	return count;
+}
+
+
+#define get_fan_para(name) static ssize_t get_##name(\
+		struct device *dev,\
+		struct device_attribute *devattr,\
+		char *buf)\
+{ \
+	struct amc6821_data *data = amc6821_update_device(dev); \
+	if (0 == data->name)\
+		return sprintf(buf, "0");\
+	return sprintf(buf, "%d\n", (int)(6000000 / data->name)); \
+}
+
+get_fan_para(fan1_input);
+get_fan_para(fan1_min);
+get_fan_para(fan1_max);
+
+static ssize_t get_fan1_fault(
+		struct device *dev,
+		struct device_attribute *devattr,
+		char *buf)
+{
+	struct amc6821_data *data = amc6821_update_device(dev);
+	if (data->stat1 & AMC6821_STAT1_FANS)
+		return sprintf(buf, "1");
+	else
+		return sprintf(buf, "0");
+}
+
+
+#define set_fan_para(name, reg) \
+static ssize_t set_##name(\
+		struct device *dev,\
+		struct device_attribute *attr,\
+		const char *buf, size_t count)\
+{ \
+	struct i2c_client *client = to_i2c_client(dev); \
+	struct amc6821_data *data = i2c_get_clientdata(client); \
+	int val = simple_strtol(buf, NULL, 10); \
+	val = 1 > val ? 0xFFFF : 6000000/val; \
+\
+	mutex_lock(&data->update_lock); \
+	data->name = (u16) SENSORS_LIMIT(val, 1, 0xFFFF); \
+	if (i2c_smbus_write_byte_data(client, reg, data->name & 0xFF)) { \
+		dev_err(&client->dev, "Register write error, aborting.\n");\
+		count = -EIO;\
+	} \
+	if (i2c_smbus_write_byte_data(client, reg+1, data->name >> 8)) { \
+		dev_err(&client->dev, "Register write error, aborting.\n");\
+		count = -EIO;\
+	} \
+	mutex_unlock(&data->update_lock); \
+	return count; \
+}
+
+
+set_fan_para(fan1_min, AMC6821_REG_TACH_LLIMITL);
+set_fan_para(fan1_max, AMC6821_REG_TACH_HLIMITL);
+
+
+static ssize_t get_fan1_div(
+		struct device *dev,
+		struct device_attribute *devattr,
+		char *buf)
+{
+	struct amc6821_data *data = amc6821_update_device(dev);
+	return sprintf(buf, "%d\n", data->fan1_div);
+}
+
+static ssize_t set_fan1_div(
+		struct device *dev,
+		struct device_attribute *attr,
+		const char *buf, size_t count)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct amc6821_data *data = i2c_get_clientdata(client);
+	int val = simple_strtol(buf, NULL, 10);
+	int config = i2c_smbus_read_byte_data(client, AMC6821_REG_CONF4);
+
+	if (config < 0) {
+		dev_err(&client->dev,
+			"Error reading configuration register, aborting.\n");
+		return -EIO;
+	}
+	mutex_lock(&data->update_lock);
+	switch (val) {
+	case 2:
+		config &= ~AMC6821_CONF4_PSPR;
+		data->fan1_div = 2;
+		break;
+	case 4:
+		config |= AMC6821_CONF4_PSPR;
+		data->fan1_div = 4;
+		break;
+	default:
+		mutex_unlock(&data->update_lock);
+		return -EINVAL;
+	}
+	if (i2c_smbus_write_byte_data(client, AMC6821_REG_CONF4, config)) {
+		dev_err(&client->dev,
+			"Configuration register write error, aborting.\n");
+		count = -EIO;
+	}
+	mutex_unlock(&data->update_lock);
+	return count;
+}
+
+
+
+static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, get_temp1_input, NULL, 0);
+static SENSOR_DEVICE_ATTR(temp1_min, S_IRUGO | S_IWUSR, get_temp1_min,
+	set_temp1_min, 0);
+static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO | S_IWUSR, get_temp1_max,
+	set_temp1_max, 0);
+static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO | S_IWUSR, get_temp1_crit,
+	set_temp1_crit, 0);
+static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO,
+	get_temp1_min_alarm, NULL, 0);
+static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO,
+	get_temp1_max_alarm, NULL, 0);
+static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO,
+	get_temp1_crit_alarm, NULL, 0);
+static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO | S_IWUSR,
+	get_temp2_input, NULL, 0);
+static SENSOR_DEVICE_ATTR(temp2_min, S_IRUGO | S_IWUSR, get_temp2_min,
+	set_temp2_min, 0);
+static SENSOR_DEVICE_ATTR(temp2_max, S_IRUGO | S_IWUSR, get_temp2_max,
+	set_temp2_max, 0);
+static SENSOR_DEVICE_ATTR(temp2_crit, S_IRUGO | S_IWUSR, get_temp2_crit,
+	set_temp2_crit, 0);
+static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO,
+	get_temp2_fault, NULL, 0);
+static SENSOR_DEVICE_ATTR(temp2_min_alarm, S_IRUGO,
+	get_temp2_min_alarm, NULL, 0);
+static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO,
+	get_temp2_max_alarm, NULL, 0);
+static SENSOR_DEVICE_ATTR(temp2_crit_alarm, S_IRUGO,
+	get_temp2_crit_alarm, NULL, 0);
+static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, get_fan1_input, NULL, 0);
+static SENSOR_DEVICE_ATTR(fan1_min, S_IRUGO | S_IWUSR,
+	get_fan1_min, set_fan1_min, 0);
+static SENSOR_DEVICE_ATTR(fan1_max, S_IRUGO | S_IWUSR,
+	get_fan1_max, set_fan1_max, 0);
+static SENSOR_DEVICE_ATTR(fan1_fault, S_IRUGO, get_fan1_fault, NULL, 0);
+static SENSOR_DEVICE_ATTR(fan1_div, S_IRUGO | S_IWUSR,
+	get_fan1_div, set_fan1_div, 0);
+
+static SENSOR_DEVICE_ATTR(pwm1, S_IWUSR | S_IRUGO, get_pwm1, set_pwm1, 0);
+static SENSOR_DEVICE_ATTR(pwm1_enable, S_IWUSR | S_IRUGO,
+	get_pwm1_enable, set_pwm1_enable, 0);
+static SENSOR_DEVICE_ATTR(pwm1_auto_point1_pwm, S_IRUGO,
+	get_pwm1_auto_point_pwm, NULL, 0);
+static SENSOR_DEVICE_ATTR(pwm1_auto_point2_pwm, S_IWUSR | S_IRUGO,
+	get_pwm1_auto_point_pwm, set_pwm1_auto_point_pwm, 1);
+static SENSOR_DEVICE_ATTR(pwm1_auto_point3_pwm, S_IRUGO,
+	get_pwm1_auto_point_pwm, NULL, 2);
+static SENSOR_DEVICE_ATTR(pwm1_auto_channels_temp, S_IRUGO,
+	get_pwm1_auto_channels_temp, NULL, 0);
+static SENSOR_DEVICE_ATTR(temp1_auto_point1_temp, S_IRUGO,
+	get_temp1_auto_point_temp, NULL, 0);
+static SENSOR_DEVICE_ATTR(temp1_auto_point2_temp, S_IWUSR | S_IRUGO,
+	get_temp1_auto_point_temp, set_temp1_auto_point_temp, 1);
+static SENSOR_DEVICE_ATTR(temp1_auto_point3_temp, S_IWUSR | S_IRUGO,
+	get_temp1_auto_point_temp, set_temp1_auto_point_temp, 2);
+
+static SENSOR_DEVICE_ATTR(temp2_auto_point1_temp, S_IWUSR | S_IRUGO,
+	get_temp2_auto_point_temp, set_temp2_auto_point_temp, 0);
+static SENSOR_DEVICE_ATTR(temp2_auto_point2_temp, S_IWUSR | S_IRUGO,
+	get_temp2_auto_point_temp, set_temp2_auto_point_temp, 1);
+static SENSOR_DEVICE_ATTR(temp2_auto_point3_temp, S_IWUSR | S_IRUGO,
+	get_temp2_auto_point_temp, set_temp2_auto_point_temp, 2);
+
+
+
+static struct attribute *amc6821_attrs[] = {
+	&sensor_dev_attr_temp1_input.dev_attr.attr,
+	&sensor_dev_attr_temp1_min.dev_attr.attr,
+	&sensor_dev_attr_temp1_max.dev_attr.attr,
+	&sensor_dev_attr_temp1_crit.dev_attr.attr,
+	&sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
+	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
+	&sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
+	&sensor_dev_attr_temp2_input.dev_attr.attr,
+	&sensor_dev_attr_temp2_min.dev_attr.attr,
+	&sensor_dev_attr_temp2_max.dev_attr.attr,
+	&sensor_dev_attr_temp2_crit.dev_attr.attr,
+	&sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
+	&sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
+	&sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
+	&sensor_dev_attr_temp2_fault.dev_attr.attr,
+	&sensor_dev_attr_fan1_input.dev_attr.attr,
+	&sensor_dev_attr_fan1_min.dev_attr.attr,
+	&sensor_dev_attr_fan1_max.dev_attr.attr,
+	&sensor_dev_attr_fan1_fault.dev_attr.attr,
+	&sensor_dev_attr_fan1_div.dev_attr.attr,
+	&sensor_dev_attr_pwm1.dev_attr.attr,
+	&sensor_dev_attr_pwm1_enable.dev_attr.attr,
+	&sensor_dev_attr_pwm1_auto_channels_temp.dev_attr.attr,
+	&sensor_dev_attr_pwm1_auto_point1_pwm.dev_attr.attr,
+	&sensor_dev_attr_pwm1_auto_point2_pwm.dev_attr.attr,
+	&sensor_dev_attr_pwm1_auto_point3_pwm.dev_attr.attr,
+	&sensor_dev_attr_temp1_auto_point1_temp.dev_attr.attr,
+	&sensor_dev_attr_temp1_auto_point2_temp.dev_attr.attr,
+	&sensor_dev_attr_temp1_auto_point3_temp.dev_attr.attr,
+	&sensor_dev_attr_temp2_auto_point1_temp.dev_attr.attr,
+	&sensor_dev_attr_temp2_auto_point2_temp.dev_attr.attr,
+	&sensor_dev_attr_temp2_auto_point3_temp.dev_attr.attr,
+	NULL
+};
+
+static struct attribute_group amc6821_attr_grp = {
+	.attrs = amc6821_attrs,
+};
+
+
+
+/* Return 0 if detection is successful, -ENODEV otherwise */
+static int amc6821_detect(
+		struct i2c_client *client,
+		int kind,
+		struct i2c_board_info *info)
+{
+	struct i2c_adapter *adapter = client->adapter;
+	int address = client->addr;
+
+	dev_dbg(&adapter->dev, "amc6821_detect called, kind = %d\n", kind);
+
+	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) {
+		dev_dbg(&adapter->dev,
+		"max6650: I2C bus doesn't support byte read mode, skipping.\n");
+		return -ENODEV;
+	}
+	if ((kind < 0) &&
+		((i2c_smbus_read_byte_data(client, AMC6821_REG_DEV_ID) &
+			0xDE) ||
+		(i2c_smbus_read_byte_data(client, AMC6821_REG_COMP_ID) &
+			0xB6))) {
+			dev_dbg(&adapter->dev,
+				"amc6821: detection failed at 0x%02x.\n",
+				address);
+		return -ENODEV;
+	}
+
+	dev_info(&adapter->dev, "amc6821: chip found at 0x%02x.\n", address);
+	strlcpy(info->type, "amc6821", I2C_NAME_SIZE);
+
+	return 0;
+}
+
+static int amc6821_probe(
+	struct i2c_client *client,
+	const struct i2c_device_id *id)
+{
+	struct amc6821_data *data;
+	int err;
+
+	data = kzalloc(sizeof(struct amc6821_data), GFP_KERNEL);
+	if (!data) {
+		dev_err(&client->dev, "out of memory.\n");
+		return -ENOMEM;
+	}
+
+
+	i2c_set_clientdata(client, data);
+	mutex_init(&data->update_lock);
+
+	/*
+	 * Initialize the amc6821 chip
+	 */
+	err = amc6821_init_client(client);
+	if (err)
+		goto err_free;
+
+	err = sysfs_create_group(&client->dev.kobj, &amc6821_attr_grp);
+	if (err)
+		goto err_free;
+
+	data->hwmon_dev = hwmon_device_register(&client->dev);
+	if (!IS_ERR(data->hwmon_dev))
+		return 0;
+
+	err = PTR_ERR(data->hwmon_dev);
+	dev_err(&client->dev, "error registering hwmon device.\n");
+	sysfs_remove_group(&client->dev.kobj, &amc6821_attr_grp);
+err_free:
+	kfree(data);
+	return err;
+}
+
+static int amc6821_remove(struct i2c_client *client)
+{
+	struct amc6821_data *data = i2c_get_clientdata(client);
+
+	hwmon_device_unregister(data->hwmon_dev);
+	sysfs_remove_group(&client->dev.kobj, &amc6821_attr_grp);
+
+	kfree(data);
+
+	return 0;
+}
+
+
+static int amc6821_init_client(struct i2c_client *client)
+{
+	int config;
+	int err = -EIO;
+
+	if (init) {
+		config = i2c_smbus_read_byte_data(client, AMC6821_REG_CONF4);
+
+		if (config < 0) {
+				dev_err(&client->dev,
+			"Error reading configuration register, aborting.\n");
+				return err;
+		}
+
+		config |= AMC6821_CONF4_MODE;
+
+		if (i2c_smbus_write_byte_data(client, AMC6821_REG_CONF4,
+				config)) {
+			dev_err(&client->dev,
+			"Configuration register write error, aborting.\n");
+			return err;
+		}
+
+		config = i2c_smbus_read_byte_data(client, AMC6821_REG_CONF3);
+
+		if (config < 0) {
+			dev_err(&client->dev,
+			"Error reading configuration register, aborting.\n");
+			return err;
+		}
+
+		config &= ~AMC6821_CONF3_THERM_FAN_EN;
+
+		if (i2c_smbus_write_byte_data(client, AMC6821_REG_CONF3,
+				config)) {
+			dev_err(&client->dev,
+			"Configuration register write error, aborting.\n");
+			return err;
+		}
+
+		config = i2c_smbus_read_byte_data(client, AMC6821_REG_CONF2);
+
+		if (config < 0) {
+			dev_err(&client->dev,
+			"Error reading configuration register, aborting.\n");
+			return err;
+		}
+
+		config &= ~AMC6821_CONF2_RTFIE;
+		config &= ~AMC6821_CONF2_LTOIE;
+		config &= ~AMC6821_CONF2_RTOIE;
+		if (i2c_smbus_write_byte_data(client,
+				AMC6821_REG_CONF2, config)) {
+			dev_err(&client->dev,
+			"Configuration register write error, aborting.\n");
+			return err;
+		}
+
+		config = i2c_smbus_read_byte_data(client, AMC6821_REG_CONF1);
+
+		if (config < 0) {
+			dev_err(&client->dev,
+			"Error reading configuration register, aborting.\n");
+			return err;
+		}
+
+		config &= ~AMC6821_CONF1_THERMOVIE;
+		config &= ~AMC6821_CONF1_FANIE;
+		config |= AMC6821_CONF1_START;
+		if (pwminv)
+			config |= AMC6821_CONF1_PWMINV;
+		else
+			config &= ~AMC6821_CONF1_PWMINV;
+
+		if (i2c_smbus_write_byte_data(
+				client, AMC6821_REG_CONF1, config)) {
+			dev_err(&client->dev,
+			"Configuration register write error, aborting.\n");
+			return err;
+		}
+	}
+	return 0;
+}
+
+
+static struct amc6821_data *amc6821_update_device(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct amc6821_data *data = i2c_get_clientdata(client);
+	int timeout = HZ;
+	u8 reg;
+
+	mutex_lock(&data->update_lock);
+
+	if (time_after(jiffies, data->last_updated + timeout) ||
+			!data->valid) {
+		data->temp1_input = i2c_smbus_read_byte_data(client,
+			AMC6821_REG_LTEMP_HI);
+		data->temp1_min = i2c_smbus_read_byte_data(client,
+			AMC6821_REG_LTEMP_LIMIT_MIN);
+		data->temp1_max = i2c_smbus_read_byte_data(client,
+			AMC6821_REG_LTEMP_LIMIT_MAX);
+		data->temp1_crit = i2c_smbus_read_byte_data(client,
+			AMC6821_REG_LTEMP_CRIT);
+
+		data->temp2_input = i2c_smbus_read_byte_data(client,
+			AMC6821_REG_RTEMP_HI);
+		data->temp2_min = i2c_smbus_read_byte_data(client,
+			AMC6821_REG_RTEMP_LIMIT_MIN);
+		data->temp2_max = i2c_smbus_read_byte_data(client,
+			AMC6821_REG_RTEMP_LIMIT_MAX);
+		data->temp2_crit = i2c_smbus_read_byte_data(client,
+			AMC6821_REG_RTEMP_CRIT);
+
+		data->stat1 = i2c_smbus_read_byte_data(client,
+			AMC6821_REG_STAT1);
+		data->stat2 = i2c_smbus_read_byte_data(client,
+			AMC6821_REG_STAT2);
+
+		data->pwm1 = i2c_smbus_read_byte_data(client,
+			AMC6821_REG_DCY);
+		data->fan1_input = i2c_smbus_read_byte_data(client,
+			AMC6821_REG_TDATA_LOW);
+		data->fan1_input += i2c_smbus_read_byte_data(client,
+			AMC6821_REG_TDATA_HI) << 8;
+		data->fan1_min = i2c_smbus_read_byte_data(client,
+			AMC6821_REG_TACH_LLIMITL);
+		data->fan1_min += i2c_smbus_read_byte_data(client,
+			AMC6821_REG_TACH_LLIMITL+1) << 8;
+		data->fan1_max = i2c_smbus_read_byte_data(client,
+			AMC6821_REG_TACH_HLIMITL);
+		data->fan1_max += i2c_smbus_read_byte_data(client,
+			AMC6821_REG_TACH_HLIMITL+1) << 8;
+		data->fan1_div = i2c_smbus_read_byte_data(client,
+			AMC6821_REG_CONF4);
+		data->fan1_div = data->fan1_div & AMC6821_CONF4_PSPR ? 4 : 2;
+
+		data->pwm1_auto_point_pwm[0] = 0;
+		data->pwm1_auto_point_pwm[2] = 255;
+		data->pwm1_auto_point_pwm[1] = i2c_smbus_read_byte_data(client,
+			AMC6821_REG_DCY_LOW_TEMP);
+
+		data->temp1_auto_point_temp[0] =
+			i2c_smbus_read_byte_data(client,
+					AMC6821_REG_PSV_TEMP);
+		data->temp2_auto_point_temp[0] =
+				data->temp1_auto_point_temp[0];
+		reg = i2c_smbus_read_byte_data(client,
+			AMC6821_REG_LTEMP_FAN_CTRL);
+		data->temp1_auto_point_temp[1] = (reg & 0xF8) >> 1;
+		reg &= 0x07;
+		reg = 0x20 >> reg;
+		if (reg > 0)
+			data->temp1_auto_point_temp[2] =
+				data->temp1_auto_point_temp[1] +
+				(data->pwm1_auto_point_pwm[2] -
+				data->pwm1_auto_point_pwm[1]) / reg;
+		else
+			data->temp1_auto_point_temp[2] = 255;
+
+		reg = i2c_smbus_read_byte_data(client,
+			AMC6821_REG_RTEMP_FAN_CTRL);
+		data->temp2_auto_point_temp[1] = (reg & 0xF8) >> 1;
+		reg &= 0x07;
+		reg = 0x20 >> reg;
+		if (reg > 0)
+			data->temp2_auto_point_temp[2] =
+				data->temp2_auto_point_temp[1] +
+				(data->pwm1_auto_point_pwm[2] -
+				data->pwm1_auto_point_pwm[1]) / reg;
+		else
+			data->temp2_auto_point_temp[2] = 255;
+
+		reg = i2c_smbus_read_byte_data(client, AMC6821_REG_CONF1);
+		reg = (reg >> 5) & 0x3;
+		switch (reg) {
+		case 0: /*open loop: software sets pwm1*/
+			data->pwm1_auto_channels_temp = 0;
+			data->pwm1_enable = 1;
+			break;
+		case 2: /*closed loop: remote T (temp2)*/
+			data->pwm1_auto_channels_temp = 2;
+			data->pwm1_enable = 2;
+			break;
+		case 3: /*closed loop: local and remote T (temp2)*/
+			data->pwm1_auto_channels_temp = 3;
+			data->pwm1_enable = 3;
+			break;
+		case 1: /*semi-open loop: software sets rpm, chip controls pwm1,
+			  *currently not implemented
+			  */
+			data->pwm1_auto_channels_temp = 0;
+			data->pwm1_enable = 0;
+			break;
+		}
+
+		data->last_updated = jiffies;
+		data->valid = 1;
+	}
+	mutex_unlock(&data->update_lock);
+	return data;
+}
+
+
+static int __init amc6821_init(void)
+{
+	return i2c_add_driver(&amc6821_driver);
+}
+
+static void __exit amc6821_exit(void)
+{
+	i2c_del_driver(&amc6821_driver);
+}
+
+module_init(amc6821_init);
+module_exit(amc6821_exit);
+
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("T. Mertelj <tomaz.mertelj@guest.arnes.si>");
+MODULE_DESCRIPTION("Texas Instruments amc6821 hwmon driver");
+MODULE_SUPPORTED_DEVICE("amc6821");