drivers/hwmon/w83793.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * w83793.c - Linux kernel driver for hardware monitoring
 * Copyright (C) 2006 Winbond Electronics Corp.
 *	      Yuan Mu
 *	      Rudolf Marek <r.marek@assembler.cz>
 * Copyright (C) 2009-2010 Sven Anders <anders@anduras.de>, ANDURAS AG.
 *		Watchdog driver part
 *		(Based partially on fschmd driver,
 *		 Copyright 2007-2008 by Hans de Goede)
 */

/*
 * Supports following chips:
 *
 * Chip	#vin	#fanin	#pwm	#temp	wchipid	vendid	i2c	ISA
 * w83793	10	12	8	6	0x7b	0x5ca3	yes	no
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/hwmon.h>
#include <linux/hwmon-vid.h>
#include <linux/hwmon-sysfs.h>
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/fs.h>
#include <linux/watchdog.h>
#include <linux/miscdevice.h>
#include <linux/uaccess.h>
#include <linux/kref.h>
#include <linux/notifier.h>
#include <linux/reboot.h>
#include <linux/jiffies.h>

/* Default values */
#define WATCHDOG_TIMEOUT 2	/* 2 minute default timeout */

/* Addresses to scan */
static const unsigned short normal_i2c[] = { 0x2c, 0x2d, 0x2e, 0x2f,
						I2C_CLIENT_END };

/* Insmod parameters */

static unsigned short force_subclients[4];
module_param_array(force_subclients, short, NULL, 0);
MODULE_PARM_DESC(force_subclients,
		 "List of subclient addresses: {bus, clientaddr, subclientaddr1, subclientaddr2}");

static bool reset;
module_param(reset, bool, 0);
MODULE_PARM_DESC(reset, "Set to 1 to reset chip, not recommended");

static int timeout = WATCHDOG_TIMEOUT;	/* default timeout in minutes */
module_param(timeout, int, 0);
MODULE_PARM_DESC(timeout,
	"Watchdog timeout in minutes. 2<= timeout <=255 (default="
				__MODULE_STRING(WATCHDOG_TIMEOUT) ")");

static bool nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, bool, 0);
MODULE_PARM_DESC(nowayout,
	"Watchdog cannot be stopped once started (default="
				__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");

/*
 * Address 0x00, 0x0d, 0x0e, 0x0f in all three banks are reserved
 * as ID, Bank Select registers
 */
#define W83793_REG_BANKSEL		0x00
#define W83793_REG_VENDORID		0x0d
#define W83793_REG_CHIPID		0x0e
#define W83793_REG_DEVICEID		0x0f

#define W83793_REG_CONFIG		0x40
#define W83793_REG_MFC			0x58
#define W83793_REG_FANIN_CTRL		0x5c
#define W83793_REG_FANIN_SEL		0x5d
#define W83793_REG_I2C_ADDR		0x0b
#define W83793_REG_I2C_SUBADDR		0x0c
#define W83793_REG_VID_INA		0x05
#define W83793_REG_VID_INB		0x06
#define W83793_REG_VID_LATCHA		0x07
#define W83793_REG_VID_LATCHB		0x08
#define W83793_REG_VID_CTRL		0x59

#define W83793_REG_WDT_LOCK		0x01
#define W83793_REG_WDT_ENABLE		0x02
#define W83793_REG_WDT_STATUS		0x03
#define W83793_REG_WDT_TIMEOUT		0x04

static u16 W83793_REG_TEMP_MODE[2] = { 0x5e, 0x5f };

#define TEMP_READ	0
#define TEMP_CRIT	1
#define TEMP_CRIT_HYST	2
#define TEMP_WARN	3
#define TEMP_WARN_HYST	4
/*
 * only crit and crit_hyst affect real-time alarm status
 * current crit crit_hyst warn warn_hyst
 */
static u16 W83793_REG_TEMP[][5] = {
	{0x1c, 0x78, 0x79, 0x7a, 0x7b},
	{0x1d, 0x7c, 0x7d, 0x7e, 0x7f},
	{0x1e, 0x80, 0x81, 0x82, 0x83},
	{0x1f, 0x84, 0x85, 0x86, 0x87},
	{0x20, 0x88, 0x89, 0x8a, 0x8b},
	{0x21, 0x8c, 0x8d, 0x8e, 0x8f},
};

#define W83793_REG_TEMP_LOW_BITS	0x22

#define W83793_REG_BEEP(index)		(0x53 + (index))
#define W83793_REG_ALARM(index)		(0x4b + (index))

#define W83793_REG_CLR_CHASSIS		0x4a	/* SMI MASK4 */
#define W83793_REG_IRQ_CTRL		0x50
#define W83793_REG_OVT_CTRL		0x51
#define W83793_REG_OVT_BEEP		0x52

#define IN_READ				0
#define IN_MAX				1
#define IN_LOW				2
static const u16 W83793_REG_IN[][3] = {
	/* Current, High, Low */
	{0x10, 0x60, 0x61},	/* Vcore A	*/
	{0x11, 0x62, 0x63},	/* Vcore B	*/
	{0x12, 0x64, 0x65},	/* Vtt		*/
	{0x14, 0x6a, 0x6b},	/* VSEN1	*/
	{0x15, 0x6c, 0x6d},	/* VSEN2	*/
	{0x16, 0x6e, 0x6f},	/* +3VSEN	*/
	{0x17, 0x70, 0x71},	/* +12VSEN	*/
	{0x18, 0x72, 0x73},	/* 5VDD		*/
	{0x19, 0x74, 0x75},	/* 5VSB		*/
	{0x1a, 0x76, 0x77},	/* VBAT		*/
};

/* Low Bits of Vcore A/B Vtt Read/High/Low */
static const u16 W83793_REG_IN_LOW_BITS[] = { 0x1b, 0x68, 0x69 };
static u8 scale_in[] = { 2, 2, 2, 16, 16, 16, 8, 24, 24, 16 };
static u8 scale_in_add[] = { 0, 0, 0, 0, 0, 0, 0, 150, 150, 0 };

#define W83793_REG_FAN(index)		(0x23 + 2 * (index))	/* High byte */
#define W83793_REG_FAN_MIN(index)	(0x90 + 2 * (index))	/* High byte */

#define W83793_REG_PWM_DEFAULT		0xb2
#define W83793_REG_PWM_ENABLE		0x207
#define W83793_REG_PWM_UPTIME		0xc3	/* Unit in 0.1 second */
#define W83793_REG_PWM_DOWNTIME		0xc4	/* Unit in 0.1 second */
#define W83793_REG_TEMP_CRITICAL	0xc5

#define PWM_DUTY			0
#define PWM_START			1
#define PWM_NONSTOP			2
#define PWM_STOP_TIME			3
#define W83793_REG_PWM(index, nr)	(((nr) == 0 ? 0xb3 : \
					 (nr) == 1 ? 0x220 : 0x218) + (index))

/* bit field, fan1 is bit0, fan2 is bit1 ... */
#define W83793_REG_TEMP_FAN_MAP(index)	(0x201 + (index))
#define W83793_REG_TEMP_TOL(index)	(0x208 + (index))
#define W83793_REG_TEMP_CRUISE(index)	(0x210 + (index))
#define W83793_REG_PWM_STOP_TIME(index)	(0x228 + (index))
#define W83793_REG_SF2_TEMP(index, nr)	(0x230 + ((index) << 4) + (nr))
#define W83793_REG_SF2_PWM(index, nr)	(0x238 + ((index) << 4) + (nr))

static inline unsigned long FAN_FROM_REG(u16 val)
{
	if ((val >= 0xfff) || (val == 0))
		return	0;
	return 1350000UL / val;
}

static inline u16 FAN_TO_REG(long rpm)
{
	if (rpm <= 0)
		return 0x0fff;
	return clamp_val((1350000 + (rpm >> 1)) / rpm, 1, 0xffe);
}

static inline unsigned long TIME_FROM_REG(u8 reg)
{
	return reg * 100;
}

static inline u8 TIME_TO_REG(unsigned long val)
{
	return clamp_val((val + 50) / 100, 0, 0xff);
}

static inline long TEMP_FROM_REG(s8 reg)
{
	return reg * 1000;
}

static inline s8 TEMP_TO_REG(long val, s8 min, s8 max)
{
	return clamp_val((val + (val < 0 ? -500 : 500)) / 1000, min, max);
}

struct w83793_data {
	struct i2c_client *lm75[2];
	struct device *hwmon_dev;
	struct mutex update_lock;
	char valid;			/* !=0 if following fields are valid */
	unsigned long last_updated;	/* In jiffies */
	unsigned long last_nonvolatile;	/* In jiffies, last time we update the
					 * nonvolatile registers
					 */

	u8 bank;
	u8 vrm;
	u8 vid[2];
	u8 in[10][3];		/* Register value, read/high/low */
	u8 in_low_bits[3];	/* Additional resolution for VCore A/B Vtt */

	u16 has_fan;		/* Only fan1- fan5 has own pins */
	u16 fan[12];		/* Register value combine */
	u16 fan_min[12];	/* Register value combine */

	s8 temp[6][5];		/* current, crit, crit_hyst,warn, warn_hyst */
	u8 temp_low_bits;	/* Additional resolution TD1-TD4 */
	u8 temp_mode[2];	/* byte 0: Temp D1-D4 mode each has 2 bits
				 * byte 1: Temp R1,R2 mode, each has 1 bit
				 */
	u8 temp_critical;	/* If reached all fan will be at full speed */
	u8 temp_fan_map[6];	/* Temp controls which pwm fan, bit field */

	u8 has_pwm;
	u8 has_temp;
	u8 has_vid;
	u8 pwm_enable;		/* Register value, each Temp has 1 bit */
	u8 pwm_uptime;		/* Register value */
	u8 pwm_downtime;	/* Register value */
	u8 pwm_default;		/* All fan default pwm, next poweron valid */
	u8 pwm[8][3];		/* Register value */
	u8 pwm_stop_time[8];
	u8 temp_cruise[6];

	u8 alarms[5];		/* realtime status registers */
	u8 beeps[5];
	u8 beep_enable;
	u8 tolerance[3];	/* Temp tolerance(Smart Fan I/II) */
	u8 sf2_pwm[6][7];	/* Smart FanII: Fan duty cycle */
	u8 sf2_temp[6][7];	/* Smart FanII: Temp level point */

	/* watchdog */
	struct i2c_client *client;
	struct mutex watchdog_lock;
	struct list_head list; /* member of the watchdog_data_list */
	struct kref kref;
	struct miscdevice watchdog_miscdev;
	unsigned long watchdog_is_open;
	char watchdog_expect_close;
	char watchdog_name[10]; /* must be unique to avoid sysfs conflict */
	unsigned int watchdog_caused_reboot;
	int watchdog_timeout; /* watchdog timeout in minutes */
};

/*
 * Somewhat ugly :( global data pointer list with all devices, so that
 * we can find our device data as when using misc_register. There is no
 * other method to get to one's device data from the open file-op and
 * for usage in the reboot notifier callback.
 */
static LIST_HEAD(watchdog_data_list);

/* Note this lock not only protect list access, but also data.kref access */
static DEFINE_MUTEX(watchdog_data_mutex);

/*
 * Release our data struct when we're detached from the i2c client *and* all
 * references to our watchdog device are released
 */
static void w83793_release_resources(struct kref *ref)
{
	struct w83793_data *data = container_of(ref, struct w83793_data, kref);
	kfree(data);
}

static u8 w83793_read_value(struct i2c_client *client, u16 reg);
static int w83793_write_value(struct i2c_client *client, u16 reg, u8 value);
static int w83793_probe(struct i2c_client *client,
			const struct i2c_device_id *id);
static int w83793_detect(struct i2c_client *client,
			 struct i2c_board_info *info);
static int w83793_remove(struct i2c_client *client);
static void w83793_init_client(struct i2c_client *client);
static void w83793_update_nonvolatile(struct device *dev);
static struct w83793_data *w83793_update_device(struct device *dev);

static const struct i2c_device_id w83793_id[] = {
	{ "w83793", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, w83793_id);

static struct i2c_driver w83793_driver = {
	.class		= I2C_CLASS_HWMON,
	.driver = {
		   .name = "w83793",
	},
	.probe		= w83793_probe,
	.remove		= w83793_remove,
	.id_table	= w83793_id,
	.detect		= w83793_detect,
	.address_list	= normal_i2c,
};

static ssize_t
vrm_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct w83793_data *data = dev_get_drvdata(dev);
	return sprintf(buf, "%d\n", data->vrm);
}

static ssize_t
show_vid(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct w83793_data *data = w83793_update_device(dev);
	struct sensor_device_attribute_2 *sensor_attr =
	    to_sensor_dev_attr_2(attr);
	int index = sensor_attr->index;

	return sprintf(buf, "%d\n", vid_from_reg(data->vid[index], data->vrm));
}

static ssize_t
vrm_store(struct device *dev, struct device_attribute *attr,
	  const char *buf, size_t count)
{
	struct w83793_data *data = dev_get_drvdata(dev);
	unsigned long val;
	int err;

	err = kstrtoul(buf, 10, &val);
	if (err)
		return err;

	if (val > 255)
		return -EINVAL;

	data->vrm = val;
	return count;
}

#define ALARM_STATUS			0
#define BEEP_ENABLE			1
static ssize_t
show_alarm_beep(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct w83793_data *data = w83793_update_device(dev);
	struct sensor_device_attribute_2 *sensor_attr =
	    to_sensor_dev_attr_2(attr);
	int nr = sensor_attr->nr;
	int index = sensor_attr->index >> 3;
	int bit = sensor_attr->index & 0x07;
	u8 val;

	if (nr == ALARM_STATUS) {
		val = (data->alarms[index] >> (bit)) & 1;
	} else {		/* BEEP_ENABLE */
		val = (data->beeps[index] >> (bit)) & 1;
	}

	return sprintf(buf, "%u\n", val);
}

static ssize_t
store_beep(struct device *dev, struct device_attribute *attr,
	   const char *buf, size_t count)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct w83793_data *data = i2c_get_clientdata(client);
	struct sensor_device_attribute_2 *sensor_attr =
	    to_sensor_dev_attr_2(attr);
	int index = sensor_attr->index >> 3;
	int shift = sensor_attr->index & 0x07;
	u8 beep_bit = 1 << shift;
	unsigned long val;
	int err;

	err = kstrtoul(buf, 10, &val);
	if (err)
		return err;

	if (val > 1)
		return -EINVAL;

	mutex_lock(&data->update_lock);
	data->beeps[index] = w83793_read_value(client, W83793_REG_BEEP(index));
	data->beeps[index] &= ~beep_bit;
	data->beeps[index] |= val << shift;
	w83793_write_value(client, W83793_REG_BEEP(index), data->beeps[index]);
	mutex_unlock(&data->update_lock);

	return count;
}

static ssize_t
show_beep_enable(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct w83793_data *data = w83793_update_device(dev);
	return sprintf(buf, "%u\n", (data->beep_enable >> 1) & 0x01);
}

static ssize_t
store_beep_enable(struct device *dev, struct device_attribute *attr,
		  const char *buf, size_t count)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct w83793_data *data = i2c_get_clientdata(client);
	unsigned long val;
	int err;

	err = kstrtoul(buf, 10, &val);
	if (err)
		return err;

	if (val > 1)
		return -EINVAL;

	mutex_lock(&data->update_lock);
	data->beep_enable = w83793_read_value(client, W83793_REG_OVT_BEEP)
			    & 0xfd;
	data->beep_enable |= val << 1;
	w83793_write_value(client, W83793_REG_OVT_BEEP, data->beep_enable);
	mutex_unlock(&data->update_lock);

	return count;
}

/* Write 0 to clear chassis alarm */
static ssize_t
store_chassis_clear(struct device *dev,
		    struct device_attribute *attr, const char *buf,
		    size_t count)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct w83793_data *data = i2c_get_clientdata(client);
	unsigned long val;
	u8 reg;
	int err;

	err = kstrtoul(buf, 10, &val);
	if (err)
		return err;
	if (val)
		return -EINVAL;

	mutex_lock(&data->update_lock);
	reg = w83793_read_value(client, W83793_REG_CLR_CHASSIS);
	w83793_write_value(client, W83793_REG_CLR_CHASSIS, reg | 0x80);
	data->valid = 0;		/* Force cache refresh */
	mutex_unlock(&data->update_lock);
	return count;
}

#define FAN_INPUT			0
#define FAN_MIN				1
static ssize_t
show_fan(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct sensor_device_attribute_2 *sensor_attr =
	    to_sensor_dev_attr_2(attr);
	int nr = sensor_attr->nr;
	int index = sensor_attr->index;
	struct w83793_data *data = w83793_update_device(dev);
	u16 val;

	if (nr == FAN_INPUT)
		val = data->fan[index] & 0x0fff;
	else
		val = data->fan_min[index] & 0x0fff;

	return sprintf(buf, "%lu\n", FAN_FROM_REG(val));
}

static ssize_t
store_fan_min(struct device *dev, struct device_attribute *attr,
	      const char *buf, size_t count)
{
	struct sensor_device_attribute_2 *sensor_attr =
	    to_sensor_dev_attr_2(attr);
	int index = sensor_attr->index;
	struct i2c_client *client = to_i2c_client(dev);
	struct w83793_data *data = i2c_get_clientdata(client);
	unsigned long val;
	int err;

	err = kstrtoul(buf, 10, &val);
	if (err)
		return err;
	val = FAN_TO_REG(val);

	mutex_lock(&data->update_lock);
	data->fan_min[index] = val;
	w83793_write_value(client, W83793_REG_FAN_MIN(index),
			   (val >> 8) & 0xff);
	w83793_write_value(client, W83793_REG_FAN_MIN(index) + 1, val & 0xff);
	mutex_unlock(&data->update_lock);

	return count;
}

static ssize_t
show_pwm(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct sensor_device_attribute_2 *sensor_attr =
	    to_sensor_dev_attr_2(attr);
	struct w83793_data *data = w83793_update_device(dev);
	u16 val;
	int nr = sensor_attr->nr;
	int index = sensor_attr->index;

	if (nr == PWM_STOP_TIME)
		val = TIME_FROM_REG(data->pwm_stop_time[index]);
	else
		val = (data->pwm[index][nr] & 0x3f) << 2;

	return sprintf(buf, "%d\n", val);
}

static ssize_t
store_pwm(struct device *dev, struct device_attribute *attr,
	  const char *buf, size_t count)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct w83793_data *data = i2c_get_clientdata(client);
	struct sensor_device_attribute_2 *sensor_attr =
	    to_sensor_dev_attr_2(attr);
	int nr = sensor_attr->nr;
	int index = sensor_attr->index;
	unsigned long val;
	int err;

	err = kstrtoul(buf, 10, &val);
	if (err)
		return err;

	mutex_lock(&data->update_lock);
	if (nr == PWM_STOP_TIME) {
		val = TIME_TO_REG(val);
		data->pwm_stop_time[index] = val;
		w83793_write_value(client, W83793_REG_PWM_STOP_TIME(index),
				   val);
	} else {
		val = clamp_val(val, 0, 0xff) >> 2;
		data->pwm[index][nr] =
		    w83793_read_value(client, W83793_REG_PWM(index, nr)) & 0xc0;
		data->pwm[index][nr] |= val;
		w83793_write_value(client, W83793_REG_PWM(index, nr),
							data->pwm[index][nr]);
	}

	mutex_unlock(&data->update_lock);
	return count;
}

static ssize_t
show_temp(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct sensor_device_attribute_2 *sensor_attr =
	    to_sensor_dev_attr_2(attr);
	int nr = sensor_attr->nr;
	int index = sensor_attr->index;
	struct w83793_data *data = w83793_update_device(dev);
	long temp = TEMP_FROM_REG(data->temp[index][nr]);

	if (nr == TEMP_READ && index < 4) {	/* Only TD1-TD4 have low bits */
		int low = ((data->temp_low_bits >> (index * 2)) & 0x03) * 250;
		temp += temp > 0 ? low : -low;
	}
	return sprintf(buf, "%ld\n", temp);
}

static ssize_t
store_temp(struct device *dev, struct device_attribute *attr,
	   const char *buf, size_t count)
{
	struct sensor_device_attribute_2 *sensor_attr =
	    to_sensor_dev_attr_2(attr);
	int nr = sensor_attr->nr;
	int index = sensor_attr->index;
	struct i2c_client *client = to_i2c_client(dev);
	struct w83793_data *data = i2c_get_clientdata(client);
	long tmp;
	int err;

	err = kstrtol(buf, 10, &tmp);
	if (err)
		return err;

	mutex_lock(&data->update_lock);
	data->temp[index][nr] = TEMP_TO_REG(tmp, -128, 127);
	w83793_write_value(client, W83793_REG_TEMP[index][nr],
			   data->temp[index][nr]);
	mutex_unlock(&data->update_lock);
	return count;
}

/*
 * TD1-TD4
 * each has 4 mode:(2 bits)
 * 0:	Stop monitor
 * 1:	Use internal temp sensor(default)
 * 2:	Reserved
 * 3:	Use sensor in Intel CPU and get result by PECI
 *
 * TR1-TR2
 * each has 2 mode:(1 bit)
 * 0:	Disable temp sensor monitor
 * 1:	To enable temp sensors monitor
 */

/* 0 disable, 6 PECI */
static u8 TO_TEMP_MODE[] = { 0, 0, 0, 6 };

static ssize_t
show_temp_mode(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct w83793_data *data = w83793_update_device(dev);
	struct sensor_device_attribute_2 *sensor_attr =
	    to_sensor_dev_attr_2(attr);
	int index = sensor_attr->index;
	u8 mask = (index < 4) ? 0x03 : 0x01;
	u8 shift = (index < 4) ? (2 * index) : (index - 4);
	u8 tmp;
	index = (index < 4) ? 0 : 1;

	tmp = (data->temp_mode[index] >> shift) & mask;

	/* for the internal sensor, found out if diode or thermistor */
	if (tmp == 1)
		tmp = index == 0 ? 3 : 4;
	else
		tmp = TO_TEMP_MODE[tmp];

	return sprintf(buf, "%d\n", tmp);
}

static ssize_t
store_temp_mode(struct device *dev, struct device_attribute *attr,
		const char *buf, size_t count)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct w83793_data *data = i2c_get_clientdata(client);
	struct sensor_device_attribute_2 *sensor_attr =
	    to_sensor_dev_attr_2(attr);
	int index = sensor_attr->index;
	u8 mask = (index < 4) ? 0x03 : 0x01;
	u8 shift = (index < 4) ? (2 * index) : (index - 4);
	unsigned long val;
	int err;

	err = kstrtoul(buf, 10, &val);
	if (err)
		return err;

	/* transform the sysfs interface values into table above */
	if ((val == 6) && (index < 4)) {
		val -= 3;
	} else if ((val == 3 && index < 4)
		|| (val == 4 && index >= 4)) {
		/* transform diode or thermistor into internal enable */
		val = !!val;
	} else {
		return -EINVAL;
	}

	index = (index < 4) ? 0 : 1;
	mutex_lock(&data->update_lock);
	data->temp_mode[index] =
	    w83793_read_value(client, W83793_REG_TEMP_MODE[index]);
	data->temp_mode[index] &= ~(mask << shift);
	data->temp_mode[index] |= val << shift;
	w83793_write_value(client, W83793_REG_TEMP_MODE[index],
							data->temp_mode[index]);
	mutex_unlock(&data->update_lock);

	return count;
}

#define SETUP_PWM_DEFAULT		0
#define SETUP_PWM_UPTIME		1	/* Unit in 0.1s */
#define SETUP_PWM_DOWNTIME		2	/* Unit in 0.1s */
#define SETUP_TEMP_CRITICAL		3
static ssize_t
show_sf_setup(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct sensor_device_attribute_2 *sensor_attr =
	    to_sensor_dev_attr_2(attr);
	int nr = sensor_attr->nr;
	struct w83793_data *data = w83793_update_device(dev);
	u32 val = 0;

	if (nr == SETUP_PWM_DEFAULT)
		val = (data->pwm_default & 0x3f) << 2;
	else if (nr == SETUP_PWM_UPTIME)
		val = TIME_FROM_REG(data->pwm_uptime);
	else if (nr == SETUP_PWM_DOWNTIME)
		val = TIME_FROM_REG(data->pwm_downtime);
	else if (nr == SETUP_TEMP_CRITICAL)
		val = TEMP_FROM_REG(data->temp_critical & 0x7f);

	return sprintf(buf, "%d\n", val);
}

static ssize_t
store_sf_setup(struct device *dev, struct device_attribute *attr,
	       const char *buf, size_t count)
{
	struct sensor_device_attribute_2 *sensor_attr =
	    to_sensor_dev_attr_2(attr);
	int nr = sensor_attr->nr;
	struct i2c_client *client = to_i2c_client(dev);
	struct w83793_data *data = i2c_get_clientdata(client);
	long val;
	int err;

	err = kstrtol(buf, 10, &val);
	if (err)
		return err;

	mutex_lock(&data->update_lock);
	if (nr == SETUP_PWM_DEFAULT) {
		data->pwm_default =
		    w83793_read_value(client, W83793_REG_PWM_DEFAULT) & 0xc0;
		data->pwm_default |= clamp_val(val, 0, 0xff) >> 2;
		w83793_write_value(client, W83793_REG_PWM_DEFAULT,
							data->pwm_default);
	} else if (nr == SETUP_PWM_UPTIME) {
		data->pwm_uptime = TIME_TO_REG(val);
		data->pwm_uptime += data->pwm_uptime == 0 ? 1 : 0;
		w83793_write_value(client, W83793_REG_PWM_UPTIME,
							data->pwm_uptime);
	} else if (nr == SETUP_PWM_DOWNTIME) {
		data->pwm_downtime = TIME_TO_REG(val);
		data->pwm_downtime += data->pwm_downtime == 0 ? 1 : 0;
		w83793_write_value(client, W83793_REG_PWM_DOWNTIME,
							data->pwm_downtime);
	} else {		/* SETUP_TEMP_CRITICAL */
		data->temp_critical =
		    w83793_read_value(client, W83793_REG_TEMP_CRITICAL) & 0x80;
		data->temp_critical |= TEMP_TO_REG(val, 0, 0x7f);
		w83793_write_value(client, W83793_REG_TEMP_CRITICAL,
							data->temp_critical);
	}

	mutex_unlock(&data->update_lock);
	return count;
}

/*
 * Temp SmartFan control
 * TEMP_FAN_MAP
 * Temp channel control which pwm fan, bitfield, bit 0 indicate pwm1...
 * It's possible two or more temp channels control the same fan, w83793
 * always prefers to pick the most critical request and applies it to
 * the related Fan.
 * It's possible one fan is not in any mapping of 6 temp channels, this
 * means the fan is manual mode
 *
 * TEMP_PWM_ENABLE
 * Each temp channel has its own SmartFan mode, and temp channel
 * control fans that are set by TEMP_FAN_MAP
 * 0:	SmartFanII mode
 * 1:	Thermal Cruise Mode
 *
 * TEMP_CRUISE
 * Target temperature in thermal cruise mode, w83793 will try to turn
 * fan speed to keep the temperature of target device around this
 * temperature.
 *
 * TEMP_TOLERANCE
 * If Temp higher or lower than target with this tolerance, w83793
 * will take actions to speed up or slow down the fan to keep the
 * temperature within the tolerance range.
 */

#define TEMP_FAN_MAP			0
#define TEMP_PWM_ENABLE			1
#define TEMP_CRUISE			2
#define TEMP_TOLERANCE			3
static ssize_t
show_sf_ctrl(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct sensor_device_attribute_2 *sensor_attr =
	    to_sensor_dev_attr_2(attr);
	int nr = sensor_attr->nr;
	int index = sensor_attr->index;
	struct w83793_data *data = w83793_update_device(dev);
	u32 val;

	if (nr == TEMP_FAN_MAP) {
		val = data->temp_fan_map[index];
	} else if (nr == TEMP_PWM_ENABLE) {
		/* +2 to transform into 2 and 3 to conform with sysfs intf */
		val = ((data->pwm_enable >> index) & 0x01) + 2;
	} else if (nr == TEMP_CRUISE) {
		val = TEMP_FROM_REG(data->temp_cruise[index] & 0x7f);
	} else {		/* TEMP_TOLERANCE */
		val = data->tolerance[index >> 1] >> ((index & 0x01) ? 4 : 0);
		val = TEMP_FROM_REG(val & 0x0f);
	}
	return sprintf(buf, "%d\n", val);
}

static ssize_t
store_sf_ctrl(struct device *dev, struct device_attribute *attr,
	      const char *buf, size_t count)
{
	struct sensor_device_attribute_2 *sensor_attr =
	    to_sensor_dev_attr_2(attr);
	int nr = sensor_attr->nr;
	int index = sensor_attr->index;
	struct i2c_client *client = to_i2c_client(dev);
	struct w83793_data *data = i2c_get_clientdata(client);
	long val;
	int err;

	err = kstrtol(buf, 10, &val);
	if (err)
		return err;

	mutex_lock(&data->update_lock);
	if (nr == TEMP_FAN_MAP) {
		val = clamp_val(val, 0, 255);
		w83793_write_value(client, W83793_REG_TEMP_FAN_MAP(index), val);
		data->temp_fan_map[index] = val;
	} else if (nr == TEMP_PWM_ENABLE) {
		if (val == 2 || val == 3) {
			data->pwm_enable =
			    w83793_read_value(client, W83793_REG_PWM_ENABLE);
			if (val - 2)
				data->pwm_enable |= 1 << index;
			else
				data->pwm_enable &= ~(1 << index);
			w83793_write_value(client, W83793_REG_PWM_ENABLE,
							data->pwm_enable);
		} else {
			mutex_unlock(&data->update_lock);
			return -EINVAL;
		}
	} else if (nr == TEMP_CRUISE) {
		data->temp_cruise[index] =
		    w83793_read_value(client, W83793_REG_TEMP_CRUISE(index));
		data->temp_cruise[index] &= 0x80;
		data->temp_cruise[index] |= TEMP_TO_REG(val, 0, 0x7f);

		w83793_write_value(client, W83793_REG_TEMP_CRUISE(index),
						data->temp_cruise[index]);
	} else {		/* TEMP_TOLERANCE */
		int i = index >> 1;
		u8 shift = (index & 0x01) ? 4 : 0;
		data->tolerance[i] =
		    w83793_read_value(client, W83793_REG_TEMP_TOL(i));

		data->tolerance[i] &= ~(0x0f << shift);
		data->tolerance[i] |= TEMP_TO_REG(val, 0, 0x0f) << shift;
		w83793_write_value(client, W83793_REG_TEMP_TOL(i),
							data->tolerance[i]);
	}

	mutex_unlock(&data->update_lock);
	return count;
}

static ssize_t
show_sf2_pwm(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct sensor_device_attribute_2 *sensor_attr =
	    to_sensor_dev_attr_2(attr);
	int nr = sensor_attr->nr;
	int index = sensor_attr->index;
	struct w83793_data *data = w83793_update_device(dev);

	return sprintf(buf, "%d\n", (data->sf2_pwm[index][nr] & 0x3f) << 2);
}

static ssize_t
store_sf2_pwm(struct device *dev, struct device_attribute *attr,
	      const char *buf, size_t count)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct w83793_data *data = i2c_get_clientdata(client);
	struct sensor_device_attribute_2 *sensor_attr =
	    to_sensor_dev_attr_2(attr);
	int nr = sensor_attr->nr;
	int index = sensor_attr->index;
	unsigned long val;
	int err;

	err = kstrtoul(buf, 10, &val);
	if (err)
		return err;
	val = clamp_val(val, 0, 0xff) >> 2;

	mutex_lock(&data->update_lock);
	data->sf2_pwm[index][nr] =
	    w83793_read_value(client, W83793_REG_SF2_PWM(index, nr)) & 0xc0;
	data->sf2_pwm[index][nr] |= val;
	w83793_write_value(client, W83793_REG_SF2_PWM(index, nr),
						data->sf2_pwm[index][nr]);
	mutex_unlock(&data->update_lock);
	return count;
}

static ssize_t
show_sf2_temp(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct sensor_device_attribute_2 *sensor_attr =
	    to_sensor_dev_attr_2(attr);
	int nr = sensor_attr->nr;
	int index = sensor_attr->index;
	struct w83793_data *data = w83793_update_device(dev);

	return sprintf(buf, "%ld\n",
		       TEMP_FROM_REG(data->sf2_temp[index][nr] & 0x7f));
}

static ssize_t
store_sf2_temp(struct device *dev, struct device_attribute *attr,
	       const char *buf, size_t count)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct w83793_data *data = i2c_get_clientdata(client);
	struct sensor_device_attribute_2 *sensor_attr =
	    to_sensor_dev_attr_2(attr);
	int nr = sensor_attr->nr;
	int index = sensor_attr->index;
	long val;
	int err;

	err = kstrtol(buf, 10, &val);
	if (err)
		return err;
	val = TEMP_TO_REG(val, 0, 0x7f);

	mutex_lock(&data->update_lock);
	data->sf2_temp[index][nr] =
	    w83793_read_value(client, W83793_REG_SF2_TEMP(index, nr)) & 0x80;
	data->sf2_temp[index][nr] |= val;
	w83793_write_value(client, W83793_REG_SF2_TEMP(index, nr),
					     data->sf2_temp[index][nr]);
	mutex_unlock(&data->update_lock);
	return count;
}

/* only Vcore A/B and Vtt have additional 2 bits precision */
static ssize_t
show_in(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct sensor_device_attribute_2 *sensor_attr =
	    to_sensor_dev_attr_2(attr);
	int nr = sensor_attr->nr;
	int index = sensor_attr->index;
	struct w83793_data *data = w83793_update_device(dev);
	u16 val = data->in[index][nr];

	if (index < 3) {
		val <<= 2;
		val += (data->in_low_bits[nr] >> (index * 2)) & 0x3;
	}
	/* voltage inputs 5VDD and 5VSB needs 150mV offset */
	val = val * scale_in[index] + scale_in_add[index];
	return sprintf(buf, "%d\n", val);
}

static ssize_t
store_in(struct device *dev, struct device_attribute *attr,
	 const char *buf, size_t count)
{
	struct sensor_device_attribute_2 *sensor_attr =
	    to_sensor_dev_attr_2(attr);
	int nr = sensor_attr->nr;
	int index = sensor_attr->index;
	struct i2c_client *client = to_i2c_client(dev);
	struct w83793_data *data = i2c_get_clientdata(client);
	unsigned long val;
	int err;

	err = kstrtoul(buf, 10, &val);
	if (err)
		return err;
	val = (val + scale_in[index] / 2) / scale_in[index];

	mutex_lock(&data->update_lock);
	if (index > 2) {
		/* fix the limit values of 5VDD and 5VSB to ALARM mechanism */
		if (nr == 1 || nr == 2)
			val -= scale_in_add[index] / scale_in[index];
		val = clamp_val(val, 0, 255);
	} else {
		val = clamp_val(val, 0, 0x3FF);
		data->in_low_bits[nr] =
		    w83793_read_value(client, W83793_REG_IN_LOW_BITS[nr]);
		data->in_low_bits[nr] &= ~(0x03 << (2 * index));
		data->in_low_bits[nr] |= (val & 0x03) << (2 * index);
		w83793_write_value(client, W83793_REG_IN_LOW_BITS[nr],
						     data->in_low_bits[nr]);
		val >>= 2;
	}
	data->in[index][nr] = val;
	w83793_write_value(client, W83793_REG_IN[index][nr],
							data->in[index][nr]);
	mutex_unlock(&data->update_lock);
	return count;
}

#define NOT_USED			-1

#define SENSOR_ATTR_IN(index)						\
	SENSOR_ATTR_2(in##index##_input, S_IRUGO, show_in, NULL,	\
		IN_READ, index),					\
	SENSOR_ATTR_2(in##index##_max, S_IRUGO | S_IWUSR, show_in,	\
		store_in, IN_MAX, index),				\
	SENSOR_ATTR_2(in##index##_min, S_IRUGO | S_IWUSR, show_in,	\
		store_in, IN_LOW, index),				\
	SENSOR_ATTR_2(in##index##_alarm, S_IRUGO, show_alarm_beep,	\
		NULL, ALARM_STATUS, index + ((index > 2) ? 1 : 0)),	\
	SENSOR_ATTR_2(in##index##_beep, S_IWUSR | S_IRUGO,		\
		show_alarm_beep, store_beep, BEEP_ENABLE,		\
		index + ((index > 2) ? 1 : 0))

#define SENSOR_ATTR_FAN(index)						\
	SENSOR_ATTR_2(fan##index##_alarm, S_IRUGO, show_alarm_beep,	\
		NULL, ALARM_STATUS, index + 17),			\
	SENSOR_ATTR_2(fan##index##_beep, S_IWUSR | S_IRUGO,		\
		show_alarm_beep, store_beep, BEEP_ENABLE, index + 17),	\
	SENSOR_ATTR_2(fan##index##_input, S_IRUGO, show_fan,		\
		NULL, FAN_INPUT, index - 1),				\
	SENSOR_ATTR_2(fan##index##_min, S_IWUSR | S_IRUGO,		\
		show_fan, store_fan_min, FAN_MIN, index - 1)

#define SENSOR_ATTR_PWM(index)						\
	SENSOR_ATTR_2(pwm##index, S_IWUSR | S_IRUGO, show_pwm,		\
		store_pwm, PWM_DUTY, index - 1),			\
	SENSOR_ATTR_2(pwm##index##_nonstop, S_IWUSR | S_IRUGO,		\
		show_pwm, store_pwm, PWM_NONSTOP, index - 1),		\
	SENSOR_ATTR_2(pwm##index##_start, S_IWUSR | S_IRUGO,		\
		show_pwm, store_pwm, PWM_START, index - 1),		\
	SENSOR_ATTR_2(pwm##index##_stop_time, S_IWUSR | S_IRUGO,	\
		show_pwm, store_pwm, PWM_STOP_TIME, index - 1)

#define SENSOR_ATTR_TEMP(index)						\
	SENSOR_ATTR_2(temp##index##_type, S_IRUGO | S_IWUSR,		\
		show_temp_mode, store_temp_mode, NOT_USED, index - 1),	\
	SENSOR_ATTR_2(temp##index##_input, S_IRUGO, show_temp,		\
		NULL, TEMP_READ, index - 1),				\
	SENSOR_ATTR_2(temp##index##_max, S_IRUGO | S_IWUSR, show_temp,	\
		store_temp, TEMP_CRIT, index - 1),			\
	SENSOR_ATTR_2(temp##index##_max_hyst, S_IRUGO | S_IWUSR,	\
		show_temp, store_temp, TEMP_CRIT_HYST, index - 1),	\
	SENSOR_ATTR_2(temp##index##_warn, S_IRUGO | S_IWUSR, show_temp,	\
		store_temp, TEMP_WARN, index - 1),			\
	SENSOR_ATTR_2(temp##index##_warn_hyst, S_IRUGO | S_IWUSR,	\
		show_temp, store_temp, TEMP_WARN_HYST, index - 1),	\
	SENSOR_ATTR_2(temp##index##_alarm, S_IRUGO,			\
		show_alarm_beep, NULL, ALARM_STATUS, index + 11),	\
	SENSOR_ATTR_2(temp##index##_beep, S_IWUSR | S_IRUGO,		\
		show_alarm_beep, store_beep, BEEP_ENABLE, index + 11),	\
	SENSOR_ATTR_2(temp##index##_auto_channels_pwm,			\
		S_IRUGO | S_IWUSR, show_sf_ctrl, store_sf_ctrl,		\
		TEMP_FAN_MAP, index - 1),				\
	SENSOR_ATTR_2(temp##index##_pwm_enable, S_IWUSR | S_IRUGO,	\
		show_sf_ctrl, store_sf_ctrl, TEMP_PWM_ENABLE,		\
		index - 1),						\
	SENSOR_ATTR_2(thermal_cruise##index, S_IRUGO | S_IWUSR,		\
		show_sf_ctrl, store_sf_ctrl, TEMP_CRUISE, index - 1),	\
	SENSOR_ATTR_2(tolerance##index, S_IRUGO | S_IWUSR, show_sf_ctrl,\
		store_sf_ctrl, TEMP_TOLERANCE, index - 1),		\
	SENSOR_ATTR_2(temp##index##_auto_point1_pwm, S_IRUGO | S_IWUSR, \
		show_sf2_pwm, store_sf2_pwm, 0, index - 1),		\
	SENSOR_ATTR_2(temp##index##_auto_point2_pwm, S_IRUGO | S_IWUSR, \
		show_sf2_pwm, store_sf2_pwm, 1, index - 1),		\
	SENSOR_ATTR_2(temp##index##_auto_point3_pwm, S_IRUGO | S_IWUSR, \
		show_sf2_pwm, store_sf2_pwm, 2, index - 1),		\
	SENSOR_ATTR_2(temp##index##_auto_point4_pwm, S_IRUGO | S_IWUSR, \
		show_sf2_pwm, store_sf2_pwm, 3, index - 1),		\
	SENSOR_ATTR_2(temp##index##_auto_point5_pwm, S_IRUGO | S_IWUSR, \
		show_sf2_pwm, store_sf2_pwm, 4, index - 1),		\
	SENSOR_ATTR_2(temp##index##_auto_point6_pwm, S_IRUGO | S_IWUSR, \
		show_sf2_pwm, store_sf2_pwm, 5, index - 1),		\
	SENSOR_ATTR_2(temp##index##_auto_point7_pwm, S_IRUGO | S_IWUSR, \
		show_sf2_pwm, store_sf2_pwm, 6, index - 1),		\
	SENSOR_ATTR_2(temp##index##_auto_point1_temp, S_IRUGO | S_IWUSR,\
		show_sf2_temp, store_sf2_temp, 0, index - 1),		\
	SENSOR_ATTR_2(temp##index##_auto_point2_temp, S_IRUGO | S_IWUSR,\
		show_sf2_temp, store_sf2_temp, 1, index - 1),		\
	SENSOR_ATTR_2(temp##index##_auto_point3_temp, S_IRUGO | S_IWUSR,\
		show_sf2_temp, store_sf2_temp, 2, index - 1),		\
	SENSOR_ATTR_2(temp##index##_auto_point4_temp, S_IRUGO | S_IWUSR,\
		show_sf2_temp, store_sf2_temp, 3, index - 1),		\
	SENSOR_ATTR_2(temp##index##_auto_point5_temp, S_IRUGO | S_IWUSR,\
		show_sf2_temp, store_sf2_temp, 4, index - 1),		\
	SENSOR_ATTR_2(temp##index##_auto_point6_temp, S_IRUGO | S_IWUSR,\
		show_sf2_temp, store_sf2_temp, 5, index - 1),		\
	SENSOR_ATTR_2(temp##index##_auto_point7_temp, S_IRUGO | S_IWUSR,\
		show_sf2_temp, store_sf2_temp, 6, index - 1)

static struct sensor_device_attribute_2 w83793_sensor_attr_2[] = {
	SENSOR_ATTR_IN(0),
	SENSOR_ATTR_IN(1),
	SENSOR_ATTR_IN(2),
	SENSOR_ATTR_IN(3),
	SENSOR_ATTR_IN(4),
	SENSOR_ATTR_IN(5),
	SENSOR_ATTR_IN(6),
	SENSOR_ATTR_IN(7),
	SENSOR_ATTR_IN(8),
	SENSOR_ATTR_IN(9),
	SENSOR_ATTR_FAN(1),
	SENSOR_ATTR_FAN(2),
	SENSOR_ATTR_FAN(3),
	SENSOR_ATTR_FAN(4),
	SENSOR_ATTR_FAN(5),
	SENSOR_ATTR_PWM(1),
	SENSOR_ATTR_PWM(2),
	SENSOR_ATTR_PWM(3),
};

static struct sensor_device_attribute_2 w83793_temp[] = {
	SENSOR_ATTR_TEMP(1),
	SENSOR_ATTR_TEMP(2),
	SENSOR_ATTR_TEMP(3),
	SENSOR_ATTR_TEMP(4),
	SENSOR_ATTR_TEMP(5),
	SENSOR_ATTR_TEMP(6),
};

/* Fan6-Fan12 */
static struct sensor_device_attribute_2 w83793_left_fan[] = {
	SENSOR_ATTR_FAN(6),
	SENSOR_ATTR_FAN(7),
	SENSOR_ATTR_FAN(8),
	SENSOR_ATTR_FAN(9),
	SENSOR_ATTR_FAN(10),
	SENSOR_ATTR_FAN(11),
	SENSOR_ATTR_FAN(12),
};

/* Pwm4-Pwm8 */
static struct sensor_device_attribute_2 w83793_left_pwm[] = {
	SENSOR_ATTR_PWM(4),
	SENSOR_ATTR_PWM(5),
	SENSOR_ATTR_PWM(6),
	SENSOR_ATTR_PWM(7),
	SENSOR_ATTR_PWM(8),
};

static struct sensor_device_attribute_2 w83793_vid[] = {
	SENSOR_ATTR_2(cpu0_vid, S_IRUGO, show_vid, NULL, NOT_USED, 0),
	SENSOR_ATTR_2(cpu1_vid, S_IRUGO, show_vid, NULL, NOT_USED, 1),
};
static DEVICE_ATTR_RW(vrm);

static struct sensor_device_attribute_2 sda_single_files[] = {
	SENSOR_ATTR_2(intrusion0_alarm, S_IWUSR | S_IRUGO, show_alarm_beep,
		      store_chassis_clear, ALARM_STATUS, 30),
	SENSOR_ATTR_2(beep_enable, S_IWUSR | S_IRUGO, show_beep_enable,
		      store_beep_enable, NOT_USED, NOT_USED),
	SENSOR_ATTR_2(pwm_default, S_IWUSR | S_IRUGO, show_sf_setup,
		      store_sf_setup, SETUP_PWM_DEFAULT, NOT_USED),
	SENSOR_ATTR_2(pwm_uptime, S_IWUSR | S_IRUGO, show_sf_setup,
		      store_sf_setup, SETUP_PWM_UPTIME, NOT_USED),
	SENSOR_ATTR_2(pwm_downtime, S_IWUSR | S_IRUGO, show_sf_setup,
		      store_sf_setup, SETUP_PWM_DOWNTIME, NOT_USED),
	SENSOR_ATTR_2(temp_critical, S_IWUSR | S_IRUGO, show_sf_setup,
		      store_sf_setup, SETUP_TEMP_CRITICAL, NOT_USED),
};

static void w83793_init_client(struct i2c_client *client)
{
	if (reset)
		w83793_write_value(client, W83793_REG_CONFIG, 0x80);

	/* Start monitoring */
	w83793_write_value(client, W83793_REG_CONFIG,
			   w83793_read_value(client, W83793_REG_CONFIG) | 0x01);
}

/*
 * Watchdog routines
 */

static int watchdog_set_timeout(struct w83793_data *data, int timeout)
{
	unsigned int mtimeout;
	int ret;

	mtimeout = DIV_ROUND_UP(timeout, 60);

	if (mtimeout > 255)
		return -EINVAL;

	mutex_lock(&data->watchdog_lock);
	if (!data->client) {
		ret = -ENODEV;
		goto leave;
	}

	data->watchdog_timeout = mtimeout;

	/* Set Timeout value (in Minutes) */
	w83793_write_value(data->client, W83793_REG_WDT_TIMEOUT,
			   data->watchdog_timeout);

	ret = mtimeout * 60;

leave:
	mutex_unlock(&data->watchdog_lock);
	return ret;
}

static int watchdog_get_timeout(struct w83793_data *data)
{
	int timeout;

	mutex_lock(&data->watchdog_lock);
	timeout = data->watchdog_timeout * 60;
	mutex_unlock(&data->watchdog_lock);

	return timeout;
}

static int watchdog_trigger(struct w83793_data *data)
{
	int ret = 0;

	mutex_lock(&data->watchdog_lock);
	if (!data->client) {
		ret = -ENODEV;
		goto leave;
	}

	/* Set Timeout value (in Minutes) */
	w83793_write_value(data->client, W83793_REG_WDT_TIMEOUT,
			   data->watchdog_timeout);

leave:
	mutex_unlock(&data->watchdog_lock);
	return ret;
}

static int watchdog_enable(struct w83793_data *data)
{
	int ret = 0;

	mutex_lock(&data->watchdog_lock);
	if (!data->client) {
		ret = -ENODEV;
		goto leave;
	}

	/* Set initial timeout */
	w83793_write_value(data->client, W83793_REG_WDT_TIMEOUT,
			   data->watchdog_timeout);

	/* Enable Soft Watchdog */
	w83793_write_value(data->client, W83793_REG_WDT_LOCK, 0x55);

leave:
	mutex_unlock(&data->watchdog_lock);
	return ret;
}

static int watchdog_disable(struct w83793_data *data)
{
	int ret = 0;

	mutex_lock(&data->watchdog_lock);
	if (!data->client) {
		ret = -ENODEV;
		goto leave;
	}

	/* Disable Soft Watchdog */
	w83793_write_value(data->client, W83793_REG_WDT_LOCK, 0xAA);

leave:
	mutex_unlock(&data->watchdog_lock);
	return ret;
}

static int watchdog_open(struct inode *inode, struct file *filp)
{
	struct w83793_data *pos, *data = NULL;
	int watchdog_is_open;

	/*
	 * We get called from drivers/char/misc.c with misc_mtx hold, and we
	 * call misc_register() from  w83793_probe() with watchdog_data_mutex
	 * hold, as misc_register() takes the misc_mtx lock, this is a possible
	 * deadlock, so we use mutex_trylock here.
	 */
	if (!mutex_trylock(&watchdog_data_mutex))
		return -ERESTARTSYS;
	list_for_each_entry(pos, &watchdog_data_list, list) {
		if (pos->watchdog_miscdev.minor == iminor(inode)) {
			data = pos;
			break;
		}
	}

	/* Check, if device is already open */
	watchdog_is_open = test_and_set_bit(0, &data->watchdog_is_open);

	/*
	 * Increase data reference counter (if not already done).
	 * Note we can never not have found data, so we don't check for this
	 */
	if (!watchdog_is_open)
		kref_get(&data->kref);

	mutex_unlock(&watchdog_data_mutex);

	/* Check, if device is already open and possibly issue error */
	if (watchdog_is_open)
		return -EBUSY;

	/* Enable Soft Watchdog */
	watchdog_enable(data);

	/* Store pointer to data into filp's private data */
	filp->private_data = data;

	return stream_open(inode, filp);
}

static int watchdog_close(struct inode *inode, struct file *filp)
{
	struct w83793_data *data = filp->private_data;

	if (data->watchdog_expect_close) {
		watchdog_disable(data);
		data->watchdog_expect_close = 0;
	} else {
		watchdog_trigger(data);
		dev_crit(&data->client->dev,
			"unexpected close, not stopping watchdog!\n");
	}

	clear_bit(0, &data->watchdog_is_open);

	/* Decrease data reference counter */
	mutex_lock(&watchdog_data_mutex);
	kref_put(&data->kref, w83793_release_resources);
	mutex_unlock(&watchdog_data_mutex);

	return 0;
}

static ssize_t watchdog_write(struct file *filp, const char __user *buf,
	size_t count, loff_t *offset)
{
	ssize_t ret;
	struct w83793_data *data = filp->private_data;

	if (count) {
		if (!nowayout) {
			size_t i;

			/* Clear it in case it was set with a previous write */
			data->watchdog_expect_close = 0;

			for (i = 0; i != count; i++) {
				char c;
				if (get_user(c, buf + i))
					return -EFAULT;
				if (c == 'V')
					data->watchdog_expect_close = 1;
			}
		}
		ret = watchdog_trigger(data);
		if (ret < 0)
			return ret;
	}
	return count;
}

static long watchdog_ioctl(struct file *filp, unsigned int cmd,
			   unsigned long arg)
{
	struct watchdog_info ident = {
		.options = WDIOF_KEEPALIVEPING |
			   WDIOF_SETTIMEOUT |
			   WDIOF_CARDRESET,
		.identity = "w83793 watchdog"
	};

	int val, ret = 0;
	struct w83793_data *data = filp->private_data;

	switch (cmd) {
	case WDIOC_GETSUPPORT:
		if (!nowayout)
			ident.options |= WDIOF_MAGICCLOSE;
		if (copy_to_user((void __user *)arg, &ident, sizeof(ident)))
			ret = -EFAULT;
		break;

	case WDIOC_GETSTATUS:
		val = data->watchdog_caused_reboot ? WDIOF_CARDRESET : 0;
		ret = put_user(val, (int __user *)arg);
		break;

	case WDIOC_GETBOOTSTATUS:
		ret = put_user(0, (int __user *)arg);
		break;

	case WDIOC_KEEPALIVE:
		ret = watchdog_trigger(data);
		break;

	case WDIOC_GETTIMEOUT:
		val = watchdog_get_timeout(data);
		ret = put_user(val, (int __user *)arg);
		break;

	case WDIOC_SETTIMEOUT:
		if (get_user(val, (int __user *)arg)) {
			ret = -EFAULT;
			break;
		}
		ret = watchdog_set_timeout(data, val);
		if (ret > 0)
			ret = put_user(ret, (int __user *)arg);
		break;

	case WDIOC_SETOPTIONS:
		if (get_user(val, (int __user *)arg)) {
			ret = -EFAULT;
			break;
		}

		if (val & WDIOS_DISABLECARD)
			ret = watchdog_disable(data);
		else if (val & WDIOS_ENABLECARD)
			ret = watchdog_enable(data);
		else
			ret = -EINVAL;

		break;
	default:
		ret = -ENOTTY;
	}
	return ret;
}

static const struct file_operations watchdog_fops = {
	.owner = THIS_MODULE,
	.llseek = no_llseek,
	.open = watchdog_open,
	.release = watchdog_close,
	.write = watchdog_write,
	.unlocked_ioctl = watchdog_ioctl,
	.compat_ioctl = compat_ptr_ioctl,
};

/*
 *	Notifier for system down
 */

static int watchdog_notify_sys(struct notifier_block *this, unsigned long code,
			       void *unused)
{
	struct w83793_data *data = NULL;

	if (code == SYS_DOWN || code == SYS_HALT) {

		/* Disable each registered watchdog */
		mutex_lock(&watchdog_data_mutex);
		list_for_each_entry(data, &watchdog_data_list, list) {
			if (data->watchdog_miscdev.minor)
				watchdog_disable(data);
		}
		mutex_unlock(&watchdog_data_mutex);
	}

	return NOTIFY_DONE;
}

/*
 *	The WDT needs to learn about soft shutdowns in order to
 *	turn the timebomb registers off.
 */

static struct notifier_block watchdog_notifier = {
	.notifier_call = watchdog_notify_sys,
};

/*
 * Init / remove routines
 */

static int w83793_remove(struct i2c_client *client)
{
	struct w83793_data *data = i2c_get_clientdata(client);
	struct device *dev = &client->dev;
	int i, tmp;

	/* Unregister the watchdog (if registered) */
	if (data->watchdog_miscdev.minor) {
		misc_deregister(&data->watchdog_miscdev);

		if (data->watchdog_is_open) {
			dev_warn(&client->dev,
				"i2c client detached with watchdog open! "
				"Stopping watchdog.\n");
			watchdog_disable(data);
		}

		mutex_lock(&watchdog_data_mutex);
		list_del(&data->list);
		mutex_unlock(&watchdog_data_mutex);

		/* Tell the watchdog code the client is gone */
		mutex_lock(&data->watchdog_lock);
		data->client = NULL;
		mutex_unlock(&data->watchdog_lock);
	}

	/* Reset Configuration Register to Disable Watch Dog Registers */
	tmp = w83793_read_value(client, W83793_REG_CONFIG);
	w83793_write_value(client, W83793_REG_CONFIG, tmp & ~0x04);

	unregister_reboot_notifier(&watchdog_notifier);

	hwmon_device_unregister(data->hwmon_dev);

	for (i = 0; i < ARRAY_SIZE(w83793_sensor_attr_2); i++)
		device_remove_file(dev,
				   &w83793_sensor_attr_2[i].dev_attr);

	for (i = 0; i < ARRAY_SIZE(sda_single_files); i++)
		device_remove_file(dev, &sda_single_files[i].dev_attr);

	for (i = 0; i < ARRAY_SIZE(w83793_vid); i++)
		device_remove_file(dev, &w83793_vid[i].dev_attr);
	device_remove_file(dev, &dev_attr_vrm);

	for (i = 0; i < ARRAY_SIZE(w83793_left_fan); i++)
		device_remove_file(dev, &w83793_left_fan[i].dev_attr);

	for (i = 0; i < ARRAY_SIZE(w83793_left_pwm); i++)
		device_remove_file(dev, &w83793_left_pwm[i].dev_attr);

	for (i = 0; i < ARRAY_SIZE(w83793_temp); i++)
		device_remove_file(dev, &w83793_temp[i].dev_attr);

	/* Decrease data reference counter */
	mutex_lock(&watchdog_data_mutex);
	kref_put(&data->kref, w83793_release_resources);
	mutex_unlock(&watchdog_data_mutex);

	return 0;
}

static int
w83793_detect_subclients(struct i2c_client *client)
{
	int i, id;
	int address = client->addr;
	u8 tmp;
	struct i2c_adapter *adapter = client->adapter;
	struct w83793_data *data = i2c_get_clientdata(client);

	id = i2c_adapter_id(adapter);
	if (force_subclients[0] == id && force_subclients[1] == address) {
		for (i = 2; i <= 3; i++) {
			if (force_subclients[i] < 0x48
			    || force_subclients[i] > 0x4f) {
				dev_err(&client->dev,
					"invalid subclient "
					"address %d; must be 0x48-0x4f\n",
					force_subclients[i]);
				return -EINVAL;
			}
		}
		w83793_write_value(client, W83793_REG_I2C_SUBADDR,
				   (force_subclients[2] & 0x07) |
				   ((force_subclients[3] & 0x07) << 4));
	}

	tmp = w83793_read_value(client, W83793_REG_I2C_SUBADDR);
	if (!(tmp & 0x08))
		data->lm75[0] = devm_i2c_new_dummy_device(&client->dev, adapter,
							  0x48 + (tmp & 0x7));
	if (!(tmp & 0x80)) {
		if (!IS_ERR(data->lm75[0])
		    && ((tmp & 0x7) == ((tmp >> 4) & 0x7))) {
			dev_err(&client->dev,
				"duplicate addresses 0x%x, "
				"use force_subclients\n", data->lm75[0]->addr);
			return -ENODEV;
		}
		data->lm75[1] = devm_i2c_new_dummy_device(&client->dev, adapter,
							  0x48 + ((tmp >> 4) & 0x7));
	}

	return 0;
}

/* Return 0 if detection is successful, -ENODEV otherwise */
static int w83793_detect(struct i2c_client *client,
			 struct i2c_board_info *info)
{
	u8 tmp, bank, chip_id;
	struct i2c_adapter *adapter = client->adapter;
	unsigned short address = client->addr;

	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
		return -ENODEV;

	bank = i2c_smbus_read_byte_data(client, W83793_REG_BANKSEL);

	tmp = bank & 0x80 ? 0x5c : 0xa3;
	/* Check Winbond vendor ID */
	if (tmp != i2c_smbus_read_byte_data(client, W83793_REG_VENDORID)) {
		pr_debug("w83793: Detection failed at check vendor id\n");
		return -ENODEV;
	}

	/*
	 * If Winbond chip, address of chip and W83793_REG_I2C_ADDR
	 * should match
	 */
	if ((bank & 0x07) == 0
	 && i2c_smbus_read_byte_data(client, W83793_REG_I2C_ADDR) !=
	    (address << 1)) {
		pr_debug("w83793: Detection failed at check i2c addr\n");
		return -ENODEV;
	}

	/* Determine the chip type now */
	chip_id = i2c_smbus_read_byte_data(client, W83793_REG_CHIPID);
	if (chip_id != 0x7b)
		return -ENODEV;

	strlcpy(info->type, "w83793", I2C_NAME_SIZE);

	return 0;
}

static int w83793_probe(struct i2c_client *client,
			const struct i2c_device_id *id)
{
	struct device *dev = &client->dev;
	static const int watchdog_minors[] = {
		WATCHDOG_MINOR, 212, 213, 214, 215
	};
	struct w83793_data *data;
	int i, tmp, val, err;
	int files_fan = ARRAY_SIZE(w83793_left_fan) / 7;
	int files_pwm = ARRAY_SIZE(w83793_left_pwm) / 5;
	int files_temp = ARRAY_SIZE(w83793_temp) / 6;

	data = kzalloc(sizeof(struct w83793_data), GFP_KERNEL);
	if (!data) {
		err = -ENOMEM;
		goto exit;
	}

	i2c_set_clientdata(client, data);
	data->bank = i2c_smbus_read_byte_data(client, W83793_REG_BANKSEL);
	mutex_init(&data->update_lock);
	mutex_init(&data->watchdog_lock);
	INIT_LIST_HEAD(&data->list);
	kref_init(&data->kref);

	/*
	 * Store client pointer in our data struct for watchdog usage
	 * (where the client is found through a data ptr instead of the
	 * otherway around)
	 */
	data->client = client;

	err = w83793_detect_subclients(client);
	if (err)
		goto free_mem;

	/* Initialize the chip */
	w83793_init_client(client);

	/*
	 * Only fan 1-5 has their own input pins,
	 * Pwm 1-3 has their own pins
	 */
	data->has_fan = 0x1f;
	data->has_pwm = 0x07;
	tmp = w83793_read_value(client, W83793_REG_MFC);
	val = w83793_read_value(client, W83793_REG_FANIN_CTRL);

	/* check the function of pins 49-56 */
	if (tmp & 0x80) {
		data->has_vid |= 0x2;	/* has VIDB */
	} else {
		data->has_pwm |= 0x18;	/* pwm 4,5 */
		if (val & 0x01) {	/* fan 6 */
			data->has_fan |= 0x20;
			data->has_pwm |= 0x20;
		}
		if (val & 0x02) {	/* fan 7 */
			data->has_fan |= 0x40;
			data->has_pwm |= 0x40;
		}
		if (!(tmp & 0x40) && (val & 0x04)) {	/* fan 8 */
			data->has_fan |= 0x80;
			data->has_pwm |= 0x80;
		}
	}

	/* check the function of pins 37-40 */
	if (!(tmp & 0x29))
		data->has_vid |= 0x1;	/* has VIDA */
	if (0x08 == (tmp & 0x0c)) {
		if (val & 0x08)	/* fan 9 */
			data->has_fan |= 0x100;
		if (val & 0x10)	/* fan 10 */
			data->has_fan |= 0x200;
	}
	if (0x20 == (tmp & 0x30)) {
		if (val & 0x20)	/* fan 11 */
			data->has_fan |= 0x400;
		if (val & 0x40)	/* fan 12 */
			data->has_fan |= 0x800;
	}

	if ((tmp & 0x01) && (val & 0x04)) {	/* fan 8, second location */
		data->has_fan |= 0x80;
		data->has_pwm |= 0x80;
	}

	tmp = w83793_read_value(client, W83793_REG_FANIN_SEL);
	if ((tmp & 0x01) && (val & 0x08)) {	/* fan 9, second location */
		data->has_fan |= 0x100;
	}
	if ((tmp & 0x02) && (val & 0x10)) {	/* fan 10, second location */
		data->has_fan |= 0x200;
	}
	if ((tmp & 0x04) && (val & 0x20)) {	/* fan 11, second location */
		data->has_fan |= 0x400;
	}
	if ((tmp & 0x08) && (val & 0x40)) {	/* fan 12, second location */
		data->has_fan |= 0x800;
	}

	/* check the temp1-6 mode, ignore former AMDSI selected inputs */
	tmp = w83793_read_value(client, W83793_REG_TEMP_MODE[0]);
	if (tmp & 0x01)
		data->has_temp |= 0x01;
	if (tmp & 0x04)
		data->has_temp |= 0x02;
	if (tmp & 0x10)
		data->has_temp |= 0x04;
	if (tmp & 0x40)
		data->has_temp |= 0x08;

	tmp = w83793_read_value(client, W83793_REG_TEMP_MODE[1]);
	if (tmp & 0x01)
		data->has_temp |= 0x10;
	if (tmp & 0x02)
		data->has_temp |= 0x20;

	/* Register sysfs hooks */
	for (i = 0; i < ARRAY_SIZE(w83793_sensor_attr_2); i++) {
		err = device_create_file(dev,
					 &w83793_sensor_attr_2[i].dev_attr);
		if (err)
			goto exit_remove;
	}

	for (i = 0; i < ARRAY_SIZE(w83793_vid); i++) {
		if (!(data->has_vid & (1 << i)))
			continue;
		err = device_create_file(dev, &w83793_vid[i].dev_attr);
		if (err)
			goto exit_remove;
	}
	if (data->has_vid) {
		data->vrm = vid_which_vrm();
		err = device_create_file(dev, &dev_attr_vrm);
		if (err)
			goto exit_remove;
	}

	for (i = 0; i < ARRAY_SIZE(sda_single_files); i++) {
		err = device_create_file(dev, &sda_single_files[i].dev_attr);
		if (err)
			goto exit_remove;

	}

	for (i = 0; i < 6; i++) {
		int j;
		if (!(data->has_temp & (1 << i)))
			continue;
		for (j = 0; j < files_temp; j++) {
			err = device_create_file(dev,
						&w83793_temp[(i) * files_temp
								+ j].dev_attr);
			if (err)
				goto exit_remove;
		}
	}

	for (i = 5; i < 12; i++) {
		int j;
		if (!(data->has_fan & (1 << i)))
			continue;
		for (j = 0; j < files_fan; j++) {
			err = device_create_file(dev,
					   &w83793_left_fan[(i - 5) * files_fan
								+ j].dev_attr);
			if (err)
				goto exit_remove;
		}
	}

	for (i = 3; i < 8; i++) {
		int j;
		if (!(data->has_pwm & (1 << i)))
			continue;
		for (j = 0; j < files_pwm; j++) {
			err = device_create_file(dev,
					   &w83793_left_pwm[(i - 3) * files_pwm
								+ j].dev_attr);
			if (err)
				goto exit_remove;
		}
	}

	data->hwmon_dev = hwmon_device_register(dev);
	if (IS_ERR(data->hwmon_dev)) {
		err = PTR_ERR(data->hwmon_dev);
		goto exit_remove;
	}

	/* Watchdog initialization */

	/* Register boot notifier */
	err = register_reboot_notifier(&watchdog_notifier);
	if (err != 0) {
		dev_err(&client->dev,
			"cannot register reboot notifier (err=%d)\n", err);
		goto exit_devunreg;
	}

	/*
	 * Enable Watchdog registers.
	 * Set Configuration Register to Enable Watch Dog Registers
	 * (Bit 2) = XXXX, X1XX.
	 */
	tmp = w83793_read_value(client, W83793_REG_CONFIG);
	w83793_write_value(client, W83793_REG_CONFIG, tmp | 0x04);

	/* Set the default watchdog timeout */
	data->watchdog_timeout = timeout;

	/* Check, if last reboot was caused by watchdog */
	data->watchdog_caused_reboot =
	  w83793_read_value(data->client, W83793_REG_WDT_STATUS) & 0x01;

	/* Disable Soft Watchdog during initialiation */
	watchdog_disable(data);

	/*
	 * We take the data_mutex lock early so that watchdog_open() cannot
	 * run when misc_register() has completed, but we've not yet added
	 * our data to the watchdog_data_list (and set the default timeout)
	 */
	mutex_lock(&watchdog_data_mutex);
	for (i = 0; i < ARRAY_SIZE(watchdog_minors); i++) {
		/* Register our watchdog part */
		snprintf(data->watchdog_name, sizeof(data->watchdog_name),
			"watchdog%c", (i == 0) ? '\0' : ('0' + i));
		data->watchdog_miscdev.name = data->watchdog_name;
		data->watchdog_miscdev.fops = &watchdog_fops;
		data->watchdog_miscdev.minor = watchdog_minors[i];

		err = misc_register(&data->watchdog_miscdev);
		if (err == -EBUSY)
			continue;
		if (err) {
			data->watchdog_miscdev.minor = 0;
			dev_err(&client->dev,
				"Registering watchdog chardev: %d\n", err);
			break;
		}

		list_add(&data->list, &watchdog_data_list);

		dev_info(&client->dev,
			"Registered watchdog chardev major 10, minor: %d\n",
			watchdog_minors[i]);
		break;
	}
	if (i == ARRAY_SIZE(watchdog_minors)) {
		data->watchdog_miscdev.minor = 0;
		dev_warn(&client->dev,
			 "Couldn't register watchdog chardev (due to no free minor)\n");
	}

	mutex_unlock(&watchdog_data_mutex);

	return 0;

	/* Unregister hwmon device */

exit_devunreg:

	hwmon_device_unregister(data->hwmon_dev);

	/* Unregister sysfs hooks */

exit_remove:
	for (i = 0; i < ARRAY_SIZE(w83793_sensor_attr_2); i++)
		device_remove_file(dev, &w83793_sensor_attr_2[i].dev_attr);

	for (i = 0; i < ARRAY_SIZE(sda_single_files); i++)
		device_remove_file(dev, &sda_single_files[i].dev_attr);

	for (i = 0; i < ARRAY_SIZE(w83793_vid); i++)
		device_remove_file(dev, &w83793_vid[i].dev_attr);

	for (i = 0; i < ARRAY_SIZE(w83793_left_fan); i++)
		device_remove_file(dev, &w83793_left_fan[i].dev_attr);

	for (i = 0; i < ARRAY_SIZE(w83793_left_pwm); i++)
		device_remove_file(dev, &w83793_left_pwm[i].dev_attr);

	for (i = 0; i < ARRAY_SIZE(w83793_temp); i++)
		device_remove_file(dev, &w83793_temp[i].dev_attr);
free_mem:
	kfree(data);
exit:
	return err;
}

static void w83793_update_nonvolatile(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct w83793_data *data = i2c_get_clientdata(client);
	int i, j;
	/*
	 * They are somewhat "stable" registers, and to update them every time
	 * takes so much time, it's just not worthy. Update them in a long
	 * interval to avoid exception.
	 */
	if (!(time_after(jiffies, data->last_nonvolatile + HZ * 300)
	      || !data->valid))
		return;
	/* update voltage limits */
	for (i = 1; i < 3; i++) {
		for (j = 0; j < ARRAY_SIZE(data->in); j++) {
			data->in[j][i] =
			    w83793_read_value(client, W83793_REG_IN[j][i]);
		}
		data->in_low_bits[i] =
		    w83793_read_value(client, W83793_REG_IN_LOW_BITS[i]);
	}

	for (i = 0; i < ARRAY_SIZE(data->fan_min); i++) {
		/* Update the Fan measured value and limits */
		if (!(data->has_fan & (1 << i)))
			continue;
		data->fan_min[i] =
		    w83793_read_value(client, W83793_REG_FAN_MIN(i)) << 8;
		data->fan_min[i] |=
		    w83793_read_value(client, W83793_REG_FAN_MIN(i) + 1);
	}

	for (i = 0; i < ARRAY_SIZE(data->temp_fan_map); i++) {
		if (!(data->has_temp & (1 << i)))
			continue;
		data->temp_fan_map[i] =
		    w83793_read_value(client, W83793_REG_TEMP_FAN_MAP(i));
		for (j = 1; j < 5; j++) {
			data->temp[i][j] =
			    w83793_read_value(client, W83793_REG_TEMP[i][j]);
		}
		data->temp_cruise[i] =
		    w83793_read_value(client, W83793_REG_TEMP_CRUISE(i));
		for (j = 0; j < 7; j++) {
			data->sf2_pwm[i][j] =
			    w83793_read_value(client, W83793_REG_SF2_PWM(i, j));
			data->sf2_temp[i][j] =
			    w83793_read_value(client,
					      W83793_REG_SF2_TEMP(i, j));
		}
	}

	for (i = 0; i < ARRAY_SIZE(data->temp_mode); i++)
		data->temp_mode[i] =
		    w83793_read_value(client, W83793_REG_TEMP_MODE[i]);

	for (i = 0; i < ARRAY_SIZE(data->tolerance); i++) {
		data->tolerance[i] =
		    w83793_read_value(client, W83793_REG_TEMP_TOL(i));
	}

	for (i = 0; i < ARRAY_SIZE(data->pwm); i++) {
		if (!(data->has_pwm & (1 << i)))
			continue;
		data->pwm[i][PWM_NONSTOP] =
		    w83793_read_value(client, W83793_REG_PWM(i, PWM_NONSTOP));
		data->pwm[i][PWM_START] =
		    w83793_read_value(client, W83793_REG_PWM(i, PWM_START));
		data->pwm_stop_time[i] =
		    w83793_read_value(client, W83793_REG_PWM_STOP_TIME(i));
	}

	data->pwm_default = w83793_read_value(client, W83793_REG_PWM_DEFAULT);
	data->pwm_enable = w83793_read_value(client, W83793_REG_PWM_ENABLE);
	data->pwm_uptime = w83793_read_value(client, W83793_REG_PWM_UPTIME);
	data->pwm_downtime = w83793_read_value(client, W83793_REG_PWM_DOWNTIME);
	data->temp_critical =
	    w83793_read_value(client, W83793_REG_TEMP_CRITICAL);
	data->beep_enable = w83793_read_value(client, W83793_REG_OVT_BEEP);

	for (i = 0; i < ARRAY_SIZE(data->beeps); i++)
		data->beeps[i] = w83793_read_value(client, W83793_REG_BEEP(i));

	data->last_nonvolatile = jiffies;
}

static struct w83793_data *w83793_update_device(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct w83793_data *data = i2c_get_clientdata(client);
	int i;

	mutex_lock(&data->update_lock);

	if (!(time_after(jiffies, data->last_updated + HZ * 2)
	      || !data->valid))
		goto END;

	/* Update the voltages measured value and limits */
	for (i = 0; i < ARRAY_SIZE(data->in); i++)
		data->in[i][IN_READ] =
		    w83793_read_value(client, W83793_REG_IN[i][IN_READ]);

	data->in_low_bits[IN_READ] =
	    w83793_read_value(client, W83793_REG_IN_LOW_BITS[IN_READ]);

	for (i = 0; i < ARRAY_SIZE(data->fan); i++) {
		if (!(data->has_fan & (1 << i)))
			continue;
		data->fan[i] =
		    w83793_read_value(client, W83793_REG_FAN(i)) << 8;
		data->fan[i] |=
		    w83793_read_value(client, W83793_REG_FAN(i) + 1);
	}

	for (i = 0; i < ARRAY_SIZE(data->temp); i++) {
		if (!(data->has_temp & (1 << i)))
			continue;
		data->temp[i][TEMP_READ] =
		    w83793_read_value(client, W83793_REG_TEMP[i][TEMP_READ]);
	}

	data->temp_low_bits =
	    w83793_read_value(client, W83793_REG_TEMP_LOW_BITS);

	for (i = 0; i < ARRAY_SIZE(data->pwm); i++) {
		if (data->has_pwm & (1 << i))
			data->pwm[i][PWM_DUTY] =
			    w83793_read_value(client,
					      W83793_REG_PWM(i, PWM_DUTY));
	}

	for (i = 0; i < ARRAY_SIZE(data->alarms); i++)
		data->alarms[i] =
		    w83793_read_value(client, W83793_REG_ALARM(i));
	if (data->has_vid & 0x01)
		data->vid[0] = w83793_read_value(client, W83793_REG_VID_INA);
	if (data->has_vid & 0x02)
		data->vid[1] = w83793_read_value(client, W83793_REG_VID_INB);
	w83793_update_nonvolatile(dev);
	data->last_updated = jiffies;
	data->valid = 1;

END:
	mutex_unlock(&data->update_lock);
	return data;
}

/*
 * Ignore the possibility that somebody change bank outside the driver
 * Must be called with data->update_lock held, except during initialization
 */
static u8 w83793_read_value(struct i2c_client *client, u16 reg)
{
	struct w83793_data *data = i2c_get_clientdata(client);
	u8 res = 0xff;
	u8 new_bank = reg >> 8;

	new_bank |= data->bank & 0xfc;
	if (data->bank != new_bank) {
		if (i2c_smbus_write_byte_data
		    (client, W83793_REG_BANKSEL, new_bank) >= 0)
			data->bank = new_bank;
		else {
			dev_err(&client->dev,
				"set bank to %d failed, fall back "
				"to bank %d, read reg 0x%x error\n",
				new_bank, data->bank, reg);
			res = 0x0;	/* read 0x0 from the chip */
			goto END;
		}
	}
	res = i2c_smbus_read_byte_data(client, reg & 0xff);
END:
	return res;
}

/* Must be called with data->update_lock held, except during initialization */
static int w83793_write_value(struct i2c_client *client, u16 reg, u8 value)
{
	struct w83793_data *data = i2c_get_clientdata(client);
	int res;
	u8 new_bank = reg >> 8;

	new_bank |= data->bank & 0xfc;
	if (data->bank != new_bank) {
		res = i2c_smbus_write_byte_data(client, W83793_REG_BANKSEL,
						new_bank);
		if (res < 0) {
			dev_err(&client->dev,
				"set bank to %d failed, fall back "
				"to bank %d, write reg 0x%x error\n",
				new_bank, data->bank, reg);
			goto END;
		}
		data->bank = new_bank;
	}

	res = i2c_smbus_write_byte_data(client, reg & 0xff, value);
END:
	return res;
}

module_i2c_driver(w83793_driver);

MODULE_AUTHOR("Yuan Mu, Sven Anders");
MODULE_DESCRIPTION("w83793 driver");
MODULE_LICENSE("GPL");