hwmon: Add support for Winbond W83L786NG/NR

Signed-off-by: Kevin Lo <kevlo@kevlo.org>
Signed-off-by: Mark M. Hoffman <mhoffman@lightlink.com>

1 files changed, 821 insertions, 0 deletions

diff --git a/drivers/hwmon/w83l786ng.c b/drivers/hwmon/w83l786ng.c
new file mode 100644
index 000000000000..1dbee4fa23ad
--- /dev/null
+++ b/drivers/hwmon/w83l786ng.c
@@ -0,0 +1,821 @@
+/*
+    w83l786ng.c - Linux kernel driver for hardware monitoring
+    Copyright (c) 2007 Kevin Lo <kevlo@kevlo.org>
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation - version 2.
+
+    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., 51 Franklin Street, Fifth Floor, Boston, MA
+    02110-1301 USA.
+*/
+
+/*
+    Supports following chips:
+
+    Chip        #vin    #fanin  #pwm    #temp   wchipid vendid  i2c     ISA
+    w83l786ng   3       2       2       2       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>
+
+/* Addresses to scan */
+static unsigned short normal_i2c[] = { 0x2e, 0x2f, I2C_CLIENT_END };
+
+/* Insmod parameters */
+I2C_CLIENT_INSMOD_1(w83l786ng);
+
+static int reset;
+module_param(reset, bool, 0);
+MODULE_PARM_DESC(reset, "Set to 1 to reset chip, not recommended");
+
+#define W83L786NG_REG_IN_MIN(nr)        (0x2C + (nr) * 2)
+#define W83L786NG_REG_IN_MAX(nr)        (0x2B + (nr) * 2)
+#define W83L786NG_REG_IN(nr)            ((nr) + 0x20)
+
+#define W83L786NG_REG_FAN(nr)           ((nr) + 0x28)
+#define W83L786NG_REG_FAN_MIN(nr)       ((nr) + 0x3B)
+
+#define W83L786NG_REG_CONFIG            0x40
+#define W83L786NG_REG_ALARM1            0x41
+#define W83L786NG_REG_ALARM2            0x42
+#define W83L786NG_REG_GPIO_EN           0x47
+#define W83L786NG_REG_MAN_ID2           0x4C
+#define W83L786NG_REG_MAN_ID1           0x4D
+#define W83L786NG_REG_CHIP_ID           0x4E
+
+#define W83L786NG_REG_DIODE             0x53
+#define W83L786NG_REG_FAN_DIV           0x54
+#define W83L786NG_REG_FAN_CFG           0x80
+
+#define W83L786NG_REG_TOLERANCE         0x8D
+
+static const u8 W83L786NG_REG_TEMP[2][3] = {
+        { 0x25,         /* TEMP 0 in DataSheet */
+          0x35,         /* TEMP 0 Over in DataSheet */
+          0x36 },       /* TEMP 0 Hyst in DataSheet */
+        { 0x26,         /* TEMP 1 in DataSheet */
+          0x37,         /* TEMP 1 Over in DataSheet */
+          0x38 }        /* TEMP 1 Hyst in DataSheet */
+};
+
+static const u8 W83L786NG_PWM_MODE_SHIFT[] = {6, 7};
+static const u8 W83L786NG_PWM_ENABLE_SHIFT[] = {2, 4};
+
+/* FAN Duty Cycle, be used to control */
+static const u8 W83L786NG_REG_PWM[] = {0x81, 0x87};
+
+
+static inline u8
+FAN_TO_REG(long rpm, int div)
+{
+        if (rpm == 0)
+                return 255;
+        rpm = SENSORS_LIMIT(rpm, 1, 1000000);
+        return SENSORS_LIMIT((1350000 + rpm * div / 2) / (rpm * div), 1, 254);
+}
+
+#define FAN_FROM_REG(val,div)   ((val) == 0   ? -1 : \
+                                ((val) == 255 ? 0 : \
+                                1350000 / ((val) * (div))))
+
+/* for temp */
+#define TEMP_TO_REG(val)        (SENSORS_LIMIT(((val) < 0 ? (val)+0x100*1000 \
+                                    : (val)) / 1000, 0, 0xff))
+#define TEMP_FROM_REG(val)      (((val) & 0x80 ? (val)-0x100 : (val)) * 1000)
+
+/* The analog voltage inputs have 8mV LSB. Since the sysfs output is
+   in mV as would be measured on the chip input pin, need to just
+   multiply/divide by 8 to translate from/to register values. */
+#define IN_TO_REG(val)          (SENSORS_LIMIT((((val) + 4) / 8), 0, 255))
+#define IN_FROM_REG(val)        ((val) * 8)
+
+#define DIV_FROM_REG(val)       (1 << (val))
+
+static inline u8
+DIV_TO_REG(long val)
+{
+        int i;
+        val = SENSORS_LIMIT(val, 1, 128) >> 1;
+        for (i = 0; i < 7; i++) {
+                if (val == 0)
+                        break;
+                val >>= 1;
+        }
+        return ((u8) i);
+}
+
+struct w83l786ng_data {
+        struct i2c_client client;
+        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 in[3];
+        u8 in_max[3];
+        u8 in_min[3];
+        u8 fan[2];
+        u8 fan_div[2];
+        u8 fan_min[2];
+        u8 temp_type[2];
+        u8 temp[2][3];
+        u8 pwm[2];
+        u8 pwm_mode[2]; /* 0->DC variable voltage
+                           1->PWM variable duty cycle */
+
+        u8 pwm_enable[2]; /* 1->manual
+                             2->thermal cruise (also called SmartFan I) */
+        u8 tolerance[2];
+};
+
+static int w83l786ng_attach_adapter(struct i2c_adapter *adapter);
+static int w83l786ng_detect(struct i2c_adapter *adapter, int address, int kind);
+static int w83l786ng_detach_client(struct i2c_client *client);
+static void w83l786ng_init_client(struct i2c_client *client);
+static struct w83l786ng_data *w83l786ng_update_device(struct device *dev);
+
+static struct i2c_driver w83l786ng_driver = {
+        .driver = {
+                   .name = "w83l786ng",
+        },
+        .attach_adapter = w83l786ng_attach_adapter,
+        .detach_client = w83l786ng_detach_client,
+};
+
+static u8
+w83l786ng_read_value(struct i2c_client *client, u8 reg)
+{
+        return i2c_smbus_read_byte_data(client, reg);
+}
+
+static int
+w83l786ng_write_value(struct i2c_client *client, u8 reg, u8 value)
+{
+        return i2c_smbus_write_byte_data(client, reg, value);
+}
+
+/* following are the sysfs callback functions */
+#define show_in_reg(reg) \
+static ssize_t \
+show_##reg(struct device *dev, struct device_attribute *attr, \
+           char *buf) \
+{ \
+        int nr = to_sensor_dev_attr(attr)->index; \
+        struct w83l786ng_data *data = w83l786ng_update_device(dev); \
+        return sprintf(buf,"%d\n", IN_FROM_REG(data->reg[nr])); \
+}
+
+show_in_reg(in)
+show_in_reg(in_min)
+show_in_reg(in_max)
+
+#define store_in_reg(REG, reg) \
+static ssize_t \
+store_in_##reg (struct device *dev, struct device_attribute *attr, \
+                const char *buf, size_t count) \
+{ \
+        int nr = to_sensor_dev_attr(attr)->index; \
+        struct i2c_client *client = to_i2c_client(dev); \
+        struct w83l786ng_data *data = i2c_get_clientdata(client); \
+        unsigned long val = simple_strtoul(buf, NULL, 10); \
+        mutex_lock(&data->update_lock); \
+        data->in_##reg[nr] = IN_TO_REG(val); \
+        w83l786ng_write_value(client, W83L786NG_REG_IN_##REG(nr), \
+                              data->in_##reg[nr]); \
+        mutex_unlock(&data->update_lock); \
+        return count; \
+}
+
+store_in_reg(MIN, min)
+store_in_reg(MAX, max)
+
+static struct sensor_device_attribute sda_in_input[] = {
+        SENSOR_ATTR(in0_input, S_IRUGO, show_in, NULL, 0),
+        SENSOR_ATTR(in1_input, S_IRUGO, show_in, NULL, 1),
+        SENSOR_ATTR(in2_input, S_IRUGO, show_in, NULL, 2),
+};
+
+static struct sensor_device_attribute sda_in_min[] = {
+        SENSOR_ATTR(in0_min, S_IWUSR | S_IRUGO, show_in_min, store_in_min, 0),
+        SENSOR_ATTR(in1_min, S_IWUSR | S_IRUGO, show_in_min, store_in_min, 1),
+        SENSOR_ATTR(in2_min, S_IWUSR | S_IRUGO, show_in_min, store_in_min, 2),
+};
+
+static struct sensor_device_attribute sda_in_max[] = {
+        SENSOR_ATTR(in0_max, S_IWUSR | S_IRUGO, show_in_max, store_in_max, 0),
+        SENSOR_ATTR(in1_max, S_IWUSR | S_IRUGO, show_in_max, store_in_max, 1),
+        SENSOR_ATTR(in2_max, S_IWUSR | S_IRUGO, show_in_max, store_in_max, 2),
+};
+
+#define show_fan_reg(reg) \
+static ssize_t show_##reg(struct device *dev, struct device_attribute *attr, \
+                          char *buf) \
+{ \
+        int nr = to_sensor_dev_attr(attr)->index; \
+        struct w83l786ng_data *data = w83l786ng_update_device(dev); \
+        return sprintf(buf,"%d\n", \
+                FAN_FROM_REG(data->fan[nr], DIV_FROM_REG(data->fan_div[nr]))); \
+}
+
+show_fan_reg(fan);
+show_fan_reg(fan_min);
+
+static ssize_t
+store_fan_min(struct device *dev, struct device_attribute *attr,
+              const char *buf, size_t count)
+{
+        int nr = to_sensor_dev_attr(attr)->index;
+        struct i2c_client *client = to_i2c_client(dev);
+        struct w83l786ng_data *data = i2c_get_clientdata(client);
+        u32 val;
+
+        val = simple_strtoul(buf, NULL, 10);
+        mutex_lock(&data->update_lock);
+        data->fan_min[nr] = FAN_TO_REG(val, DIV_FROM_REG(data->fan_div[nr]));
+        w83l786ng_write_value(client, W83L786NG_REG_FAN_MIN(nr),
+                              data->fan_min[nr]);
+        mutex_unlock(&data->update_lock);
+
+        return count;
+}
+
+static ssize_t
+show_fan_div(struct device *dev, struct device_attribute *attr,
+             char *buf)
+{
+        int nr = to_sensor_dev_attr(attr)->index;
+        struct w83l786ng_data *data = w83l786ng_update_device(dev);
+        return sprintf(buf, "%u\n", DIV_FROM_REG(data->fan_div[nr]));
+}
+
+/* Note: we save and restore the fan minimum here, because its value is
+   determined in part by the fan divisor.  This follows the principle of
+   least surprise; the user doesn't expect the fan minimum to change just
+   because the divisor changed. */
+static ssize_t
+store_fan_div(struct device *dev, struct device_attribute *attr,
+              const char *buf, size_t count)
+{
+        int nr = to_sensor_dev_attr(attr)->index;
+        struct i2c_client *client = to_i2c_client(dev);
+        struct w83l786ng_data *data = i2c_get_clientdata(client);
+
+        unsigned long min;
+        u8 tmp_fan_div;
+        u8 fan_div_reg;
+        u8 keep_mask = 0;
+        u8 new_shift = 0;
+
+        /* Save fan_min */
+        mutex_lock(&data->update_lock);
+        min = FAN_FROM_REG(data->fan_min[nr], DIV_FROM_REG(data->fan_div[nr]));
+
+        data->fan_div[nr] = DIV_TO_REG(simple_strtoul(buf, NULL, 10));
+
+        switch (nr) {
+        case 0:
+                keep_mask = 0xf8;
+                new_shift = 0;
+                break;
+        case 1:
+                keep_mask = 0x8f;
+                new_shift = 4;
+                break;
+        }
+
+        fan_div_reg = w83l786ng_read_value(client, W83L786NG_REG_FAN_DIV)
+                                           & keep_mask;
+
+        tmp_fan_div = (data->fan_div[nr] << new_shift) & ~keep_mask;
+
+        w83l786ng_write_value(client, W83L786NG_REG_FAN_DIV,
+                              fan_div_reg | tmp_fan_div);
+
+        /* Restore fan_min */
+        data->fan_min[nr] = FAN_TO_REG(min, DIV_FROM_REG(data->fan_div[nr]));
+        w83l786ng_write_value(client, W83L786NG_REG_FAN_MIN(nr),
+                              data->fan_min[nr]);
+        mutex_unlock(&data->update_lock);
+
+        return count;
+}
+
+static struct sensor_device_attribute sda_fan_input[] = {
+        SENSOR_ATTR(fan1_input, S_IRUGO, show_fan, NULL, 0),
+        SENSOR_ATTR(fan2_input, S_IRUGO, show_fan, NULL, 1),
+};
+
+static struct sensor_device_attribute sda_fan_min[] = {
+        SENSOR_ATTR(fan1_min, S_IWUSR | S_IRUGO, show_fan_min,
+                    store_fan_min, 0),
+        SENSOR_ATTR(fan2_min, S_IWUSR | S_IRUGO, show_fan_min,
+                    store_fan_min, 1),
+};
+
+static struct sensor_device_attribute sda_fan_div[] = {
+        SENSOR_ATTR(fan1_div, S_IWUSR | S_IRUGO, show_fan_div,
+                    store_fan_div, 0),
+        SENSOR_ATTR(fan2_div, S_IWUSR | S_IRUGO, show_fan_div,
+                    store_fan_div, 1),
+};
+
+
+/* read/write the temperature, includes measured value and limits */
+
+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 w83l786ng_data *data = w83l786ng_update_device(dev);
+        return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[nr][index]));
+}
+
+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 w83l786ng_data *data = i2c_get_clientdata(client);
+        s32 val;
+
+        val = simple_strtol(buf, NULL, 10);
+        mutex_lock(&data->update_lock);
+        data->temp[nr][index] = TEMP_TO_REG(val);
+        w83l786ng_write_value(client, W83L786NG_REG_TEMP[nr][index],
+                              data->temp[nr][index]);
+        mutex_unlock(&data->update_lock);
+
+        return count;
+}
+
+static struct sensor_device_attribute_2 sda_temp_input[] = {
+        SENSOR_ATTR_2(temp1_input, S_IRUGO, show_temp, NULL, 0, 0),
+        SENSOR_ATTR_2(temp2_input, S_IRUGO, show_temp, NULL, 1, 0),
+};
+
+static struct sensor_device_attribute_2 sda_temp_max[] = {
+        SENSOR_ATTR_2(temp1_max, S_IRUGO | S_IWUSR,
+                      show_temp, store_temp, 0, 1),
+        SENSOR_ATTR_2(temp2_max, S_IRUGO | S_IWUSR,
+                      show_temp, store_temp, 1, 1),
+};
+
+static struct sensor_device_attribute_2 sda_temp_max_hyst[] = {
+        SENSOR_ATTR_2(temp1_max_hyst, S_IRUGO | S_IWUSR,
+                      show_temp, store_temp, 0, 2),
+        SENSOR_ATTR_2(temp2_max_hyst, S_IRUGO | S_IWUSR,
+                      show_temp, store_temp, 1, 2),
+};
+
+#define show_pwm_reg(reg) \
+static ssize_t show_##reg (struct device *dev, struct device_attribute *attr, \
+                           char *buf) \
+{ \
+        struct w83l786ng_data *data = w83l786ng_update_device(dev); \
+        int nr = to_sensor_dev_attr(attr)->index; \
+        return sprintf(buf, "%d\n", data->reg[nr]); \
+}
+
+show_pwm_reg(pwm_mode)
+show_pwm_reg(pwm_enable)
+show_pwm_reg(pwm)
+
+static ssize_t
+store_pwm_mode(struct device *dev, struct device_attribute *attr,
+               const char *buf, size_t count)
+{
+        int nr = to_sensor_dev_attr(attr)->index;
+        struct i2c_client *client = to_i2c_client(dev);
+        struct w83l786ng_data *data = i2c_get_clientdata(client);
+        u32 val = simple_strtoul(buf, NULL, 10);
+        u8 reg;
+
+        if (val > 1)
+                return -EINVAL;
+        mutex_lock(&data->update_lock);
+        data->pwm_mode[nr] = val;
+        reg = w83l786ng_read_value(client, W83L786NG_REG_FAN_CFG);
+        reg &= ~(1 << W83L786NG_PWM_MODE_SHIFT[nr]);
+        if (!val)
+                reg |= 1 << W83L786NG_PWM_MODE_SHIFT[nr];
+        w83l786ng_write_value(client, W83L786NG_REG_FAN_CFG, reg);
+        mutex_unlock(&data->update_lock);
+        return count;
+}
+
+static ssize_t
+store_pwm(struct device *dev, struct device_attribute *attr,
+          const char *buf, size_t count)
+{
+        int nr = to_sensor_dev_attr(attr)->index;
+        struct i2c_client *client = to_i2c_client(dev);
+        struct w83l786ng_data *data = i2c_get_clientdata(client);
+        u32 val = SENSORS_LIMIT(simple_strtoul(buf, NULL, 10), 0, 255);
+
+        mutex_lock(&data->update_lock);
+        data->pwm[nr] = val;
+        w83l786ng_write_value(client, W83L786NG_REG_PWM[nr], val);
+        mutex_unlock(&data->update_lock);
+        return count;
+}
+
+static ssize_t
+store_pwm_enable(struct device *dev, struct device_attribute *attr,
+                 const char *buf, size_t count)
+{
+        int nr = to_sensor_dev_attr(attr)->index;
+        struct i2c_client *client = to_i2c_client(dev);
+        struct w83l786ng_data *data = i2c_get_clientdata(client);
+        u32 val = simple_strtoul(buf, NULL, 10);
+
+        u8 reg;
+
+        if (!val || (val > 2))  /* only modes 1 and 2 are supported */
+                return -EINVAL;
+
+        mutex_lock(&data->update_lock);
+        reg = w83l786ng_read_value(client, W83L786NG_REG_FAN_CFG);
+        data->pwm_enable[nr] = val;
+        reg &= ~(0x02 << W83L786NG_PWM_ENABLE_SHIFT[nr]);
+        reg |= (val - 1) << W83L786NG_PWM_ENABLE_SHIFT[nr];
+        w83l786ng_write_value(client, W83L786NG_REG_FAN_CFG, reg);
+        mutex_unlock(&data->update_lock);
+        return count;
+}
+
+static struct sensor_device_attribute sda_pwm[] = {
+        SENSOR_ATTR(pwm1, S_IWUSR | S_IRUGO, show_pwm, store_pwm, 0),
+        SENSOR_ATTR(pwm2, S_IWUSR | S_IRUGO, show_pwm, store_pwm, 1),
+};
+
+static struct sensor_device_attribute sda_pwm_mode[] = {
+        SENSOR_ATTR(pwm1_mode, S_IWUSR | S_IRUGO, show_pwm_mode,
+                    store_pwm_mode, 0),
+        SENSOR_ATTR(pwm2_mode, S_IWUSR | S_IRUGO, show_pwm_mode,
+                    store_pwm_mode, 1),
+};
+
+static struct sensor_device_attribute sda_pwm_enable[] = {
+        SENSOR_ATTR(pwm1_enable, S_IWUSR | S_IRUGO, show_pwm_enable,
+                    store_pwm_enable, 0),
+        SENSOR_ATTR(pwm2_enable, S_IWUSR | S_IRUGO, show_pwm_enable,
+                    store_pwm_enable, 1),
+};
+
+/* For Smart Fan I/Thermal Cruise and Smart Fan II */
+static ssize_t
+show_tolerance(struct device *dev, struct device_attribute *attr, char *buf)
+{
+        int nr = to_sensor_dev_attr(attr)->index;
+        struct w83l786ng_data *data = w83l786ng_update_device(dev);
+        return sprintf(buf, "%ld\n", (long)data->tolerance[nr]);
+}
+
+static ssize_t
+store_tolerance(struct device *dev, struct device_attribute *attr,
+                const char *buf, size_t count)
+{
+        int nr = to_sensor_dev_attr(attr)->index;
+        struct i2c_client *client = to_i2c_client(dev);
+        struct w83l786ng_data *data = i2c_get_clientdata(client);
+        u32 val;
+        u8 tol_tmp, tol_mask;
+
+        val = simple_strtoul(buf, NULL, 10);
+
+        mutex_lock(&data->update_lock);
+        tol_mask = w83l786ng_read_value(client,
+            W83L786NG_REG_TOLERANCE) & ((nr == 1) ? 0x0f : 0xf0);
+        tol_tmp = SENSORS_LIMIT(val, 0, 15);
+        tol_tmp &= 0x0f;
+        data->tolerance[nr] = tol_tmp;
+        if (nr == 1) {
+                tol_tmp <<= 4;
+        }
+
+        w83l786ng_write_value(client, W83L786NG_REG_TOLERANCE,
+                              tol_mask | tol_tmp);
+        mutex_unlock(&data->update_lock);
+        return count;
+}
+
+static struct sensor_device_attribute sda_tolerance[] = {
+        SENSOR_ATTR(pwm1_tolerance, S_IWUSR | S_IRUGO,
+                    show_tolerance, store_tolerance, 0),
+        SENSOR_ATTR(pwm2_tolerance, S_IWUSR | S_IRUGO,
+                    show_tolerance, store_tolerance, 1),
+};
+
+
+#define IN_UNIT_ATTRS(X)        \
+        &sda_in_input[X].dev_attr.attr,         \
+        &sda_in_min[X].dev_attr.attr,           \
+        &sda_in_max[X].dev_attr.attr
+
+#define FAN_UNIT_ATTRS(X)       \
+        &sda_fan_input[X].dev_attr.attr,        \
+        &sda_fan_min[X].dev_attr.attr,          \
+        &sda_fan_div[X].dev_attr.attr
+
+#define TEMP_UNIT_ATTRS(X)      \
+        &sda_temp_input[X].dev_attr.attr,       \
+        &sda_temp_max[X].dev_attr.attr,         \
+        &sda_temp_max_hyst[X].dev_attr.attr
+
+#define PWM_UNIT_ATTRS(X)       \
+        &sda_pwm[X].dev_attr.attr,              \
+        &sda_pwm_mode[X].dev_attr.attr,         \
+        &sda_pwm_enable[X].dev_attr.attr
+
+#define TOLERANCE_UNIT_ATTRS(X) \
+        &sda_tolerance[X].dev_attr.attr
+
+static struct attribute *w83l786ng_attributes[] = {
+        IN_UNIT_ATTRS(0),
+        IN_UNIT_ATTRS(1),
+        IN_UNIT_ATTRS(2),
+        FAN_UNIT_ATTRS(0),
+        FAN_UNIT_ATTRS(1),
+        TEMP_UNIT_ATTRS(0),
+        TEMP_UNIT_ATTRS(1),
+        PWM_UNIT_ATTRS(0),
+        PWM_UNIT_ATTRS(1),
+        TOLERANCE_UNIT_ATTRS(0),
+        TOLERANCE_UNIT_ATTRS(1),
+        NULL
+};
+
+static const struct attribute_group w83l786ng_group = {
+        .attrs = w83l786ng_attributes,
+};
+
+static int
+w83l786ng_attach_adapter(struct i2c_adapter *adapter)
+{
+        if (!(adapter->class & I2C_CLASS_HWMON))
+                return 0;
+        return i2c_probe(adapter, &addr_data, w83l786ng_detect);
+}
+
+static int
+w83l786ng_detect(struct i2c_adapter *adapter, int address, int kind)
+{
+        struct i2c_client *client;
+        struct device *dev;
+        struct w83l786ng_data *data;
+        int i, err = 0;
+        u8 reg_tmp;
+
+        if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) {
+                goto exit;
+        }
+
+        /* OK. For now, we presume we have a valid client. We now create the
+           client structure, even though we cannot fill it completely yet.
+           But it allows us to access w83l786ng_{read,write}_value. */
+
+        if (!(data = kzalloc(sizeof(struct w83l786ng_data), GFP_KERNEL))) {
+                err = -ENOMEM;
+                goto exit;
+        }
+
+        client = &data->client;
+        dev = &client->dev;
+        i2c_set_clientdata(client, data);
+        client->addr = address;
+        client->adapter = adapter;
+        client->driver = &w83l786ng_driver;
+
+        /*
+         * Now we do the remaining detection. A negative kind means that
+         * the driver was loaded with no force parameter (default), so we
+         * must both detect and identify the chip (actually there is only
+         * one possible kind of chip for now, W83L786NG). A zero kind means
+         * that the driver was loaded with the force parameter, the detection
+         * step shall be skipped. A positive kind means that the driver
+         * was loaded with the force parameter and a given kind of chip is
+         * requested, so both the detection and the identification steps
+         * are skipped.
+         */
+        if (kind < 0) { /* detection */
+                if (((w83l786ng_read_value(client,
+                    W83L786NG_REG_CONFIG) & 0x80) != 0x00)) {
+                        dev_dbg(&adapter->dev,
+                                "W83L786NG detection failed at 0x%02x.\n",
+                                address);
+                        goto exit_free;
+                }
+        }
+
+        if (kind <= 0) { /* identification */
+                u16 man_id;
+                u8 chip_id;
+
+                man_id = (w83l786ng_read_value(client,
+                    W83L786NG_REG_MAN_ID1) << 8) +
+                    w83l786ng_read_value(client, W83L786NG_REG_MAN_ID2);
+                chip_id = w83l786ng_read_value(client, W83L786NG_REG_CHIP_ID);
+
+                if (man_id == 0x5CA3) { /* Winbond */
+                        if (chip_id == 0x80) { /* W83L786NG */
+                                kind = w83l786ng;
+                        }
+                }
+
+                if (kind <= 0) { /* identification failed */
+                        dev_info(&adapter->dev,
+                            "Unsupported chip (man_id=0x%04X, "
+                            "chip_id=0x%02X).\n", man_id, chip_id);
+                        goto exit_free;
+                }
+        }
+
+        /* Fill in the remaining client fields and put into the global list */
+        strlcpy(client->name, "w83l786ng", I2C_NAME_SIZE);
+        mutex_init(&data->update_lock);
+
+        /* Tell the I2C layer a new client has arrived */
+        if ((err = i2c_attach_client(client)))
+                goto exit_free;
+
+        /* Initialize the chip */
+        w83l786ng_init_client(client);
+
+        /* A few vars need to be filled upon startup */
+        for (i = 0; i < 2; i++) {
+                data->fan_min[i] = w83l786ng_read_value(client,
+                    W83L786NG_REG_FAN_MIN(i));
+        }
+
+        /* Update the fan divisor */
+        reg_tmp = w83l786ng_read_value(client, W83L786NG_REG_FAN_DIV);
+        data->fan_div[0] = reg_tmp & 0x07;
+        data->fan_div[1] = (reg_tmp >> 4) & 0x07;
+
+        /* Register sysfs hooks */
+        if ((err = sysfs_create_group(&client->dev.kobj, &w83l786ng_group)))
+                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;
+        }
+
+        return 0;
+
+        /* Unregister sysfs hooks */
+
+exit_remove:
+        sysfs_remove_group(&client->dev.kobj, &w83l786ng_group);
+        i2c_detach_client(client);
+exit_free:
+        kfree(data);
+exit:
+        return err;
+}
+
+static int
+w83l786ng_detach_client(struct i2c_client *client)
+{
+        struct w83l786ng_data *data = i2c_get_clientdata(client);
+        int err;
+
+        hwmon_device_unregister(data->hwmon_dev);
+        sysfs_remove_group(&client->dev.kobj, &w83l786ng_group);
+
+        if ((err = i2c_detach_client(client)))
+                return err;
+
+        kfree(data);
+
+        return 0;
+}
+
+static void
+w83l786ng_init_client(struct i2c_client *client)
+{
+        u8 tmp;
+
+        if (reset)
+                w83l786ng_write_value(client, W83L786NG_REG_CONFIG, 0x80);
+
+        /* Start monitoring */
+        tmp = w83l786ng_read_value(client, W83L786NG_REG_CONFIG);
+        if (!(tmp & 0x01))
+                w83l786ng_write_value(client, W83L786NG_REG_CONFIG, tmp | 0x01);
+}
+
+static struct w83l786ng_data *w83l786ng_update_device(struct device *dev)
+{
+        struct i2c_client *client = to_i2c_client(dev);
+        struct w83l786ng_data *data = i2c_get_clientdata(client);
+        int i, j;
+        u8 reg_tmp, pwmcfg;
+
+        mutex_lock(&data->update_lock);
+        if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
+            || !data->valid) {
+                dev_dbg(&client->dev, "Updating w83l786ng data.\n");
+
+                /* Update the voltages measured value and limits */
+                for (i = 0; i < 3; i++) {
+                        data->in[i] = w83l786ng_read_value(client,
+                            W83L786NG_REG_IN(i));
+                        data->in_min[i] = w83l786ng_read_value(client,
+                            W83L786NG_REG_IN_MIN(i));
+                        data->in_max[i] = w83l786ng_read_value(client,
+                            W83L786NG_REG_IN_MAX(i));
+                }
+
+                /* Update the fan counts and limits */
+                for (i = 0; i < 2; i++) {
+                        data->fan[i] = w83l786ng_read_value(client,
+                            W83L786NG_REG_FAN(i));
+                        data->fan_min[i] = w83l786ng_read_value(client,
+                            W83L786NG_REG_FAN_MIN(i));
+                }
+
+                /* Update the fan divisor */
+                reg_tmp = w83l786ng_read_value(client, W83L786NG_REG_FAN_DIV);
+                data->fan_div[0] = reg_tmp & 0x07;
+                data->fan_div[1] = (reg_tmp >> 4) & 0x07;
+
+                pwmcfg = w83l786ng_read_value(client, W83L786NG_REG_FAN_CFG);
+                for (i = 0; i < 2; i++) {
+                        data->pwm_mode[i] =
+                            ((pwmcfg >> W83L786NG_PWM_MODE_SHIFT[i]) & 1)
+                            ? 0 : 1;
+                        data->pwm_enable[i] =
+                            ((pwmcfg >> W83L786NG_PWM_ENABLE_SHIFT[i]) & 2) + 1;
+                        data->pwm[i] = w83l786ng_read_value(client,
+                            W83L786NG_REG_PWM[i]);
+                }
+
+
+                /* Update the temperature sensors */
+                for (i = 0; i < 2; i++) {
+                        for (j = 0; j < 3; j++) {
+                                data->temp[i][j] = w83l786ng_read_value(client,
+                                    W83L786NG_REG_TEMP[i][j]);
+                        }
+                }
+
+                /* Update Smart Fan I/II tolerance */
+                reg_tmp = w83l786ng_read_value(client, W83L786NG_REG_TOLERANCE);
+                data->tolerance[0] = reg_tmp & 0x0f;
+                data->tolerance[1] = (reg_tmp >> 4) & 0x0f;
+
+                data->last_updated = jiffies;
+                data->valid = 1;
+
+        }
+
+        mutex_unlock(&data->update_lock);
+
+        return data;
+}
+
+static int __init
+sensors_w83l786ng_init(void)
+{
+        return i2c_add_driver(&w83l786ng_driver);
+}
+
+static void __exit
+sensors_w83l786ng_exit(void)
+{
+        i2c_del_driver(&w83l786ng_driver);
+}
+
+MODULE_AUTHOR("Kevin Lo");
+MODULE_DESCRIPTION("w83l786ng driver");
+MODULE_LICENSE("GPL");
+
+module_init(sensors_w83l786ng_init);
+module_exit(sensors_w83l786ng_exit);