drm/i915: Fix i965 secured batchbuffer usage (CVE-2007-3851)

[linux/fpc-iii.git] / drivers / hwmon / lm87.c

/*
 * lm87.c
 *
 * Copyright (C) 2000       Frodo Looijaard <frodol@dds.nl>
 *                          Philip Edelbrock <phil@netroedge.com>
 *                          Stephen Rousset <stephen.rousset@rocketlogix.com>
 *                          Dan Eaton <dan.eaton@rocketlogix.com>
 * Copyright (C) 2004       Jean Delvare <khali@linux-fr.org>
 *
 * Original port to Linux 2.6 by Jeff Oliver.
 *
 * The LM87 is a sensor chip made by National Semiconductor. It monitors up
 * to 8 voltages (including its own power source), up to three temperatures
 * (its own plus up to two external ones) and up to two fans. The default
 * configuration is 6 voltages, two temperatures and two fans (see below).
 * Voltages are scaled internally with ratios such that the nominal value of
 * each voltage correspond to a register value of 192 (which means a
 * resolution of about 0.5% of the nominal value). Temperature values are
 * reported with a 1 deg resolution and a 3-4 deg accuracy. Complete
 * datasheet can be obtained from National's website at:
 *   http://www.national.com/pf/LM/LM87.html
 *
 * Some functions share pins, so not all functions are available at the same
 * time. Which are depends on the hardware setup. This driver assumes that
 * the BIOS configured the chip correctly. In that respect, it  differs from
 * the original driver (from lm_sensors for Linux 2.4), which would force the
 * LM87 to an arbitrary, compile-time chosen mode, regardless of the actual
 * chipset wiring.
 * For reference, here is the list of exclusive functions:
 *  - in0+in5 (default) or temp3
 *  - fan1 (default) or in6
 *  - fan2 (default) or in7
 *  - VID lines (default) or IRQ lines (not handled by this driver)
 *
 * The LM87 additionally features an analog output, supposedly usable to
 * control the speed of a fan. All new chips use pulse width modulation
 * instead. The LM87 is the only hardware monitoring chipset I know of
 * which uses amplitude modulation. Be careful when using this feature.
 *
 * 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/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-vid.h>
#include <linux/err.h>
#include <linux/mutex.h>

/*
 * Addresses to scan
 * LM87 has three possible addresses: 0x2c, 0x2d and 0x2e.
 */

static unsigned short normal_i2c[] = { 0x2c, 0x2d, 0x2e, I2C_CLIENT_END };

/*
 * Insmod parameters
 */

I2C_CLIENT_INSMOD_1(lm87);

/*
 * The LM87 registers
 */

/* nr in 0..5 */
#define LM87_REG_IN(nr)                 (0x20 + (nr))
#define LM87_REG_IN_MAX(nr)             (0x2B + (nr) * 2)
#define LM87_REG_IN_MIN(nr)             (0x2C + (nr) * 2)
/* nr in 0..1 */
#define LM87_REG_AIN(nr)                (0x28 + (nr))
#define LM87_REG_AIN_MIN(nr)            (0x1A + (nr))
#define LM87_REG_AIN_MAX(nr)            (0x3B + (nr))

static u8 LM87_REG_TEMP[3] = { 0x27, 0x26, 0x20 };
static u8 LM87_REG_TEMP_HIGH[3] = { 0x39, 0x37, 0x2B };
static u8 LM87_REG_TEMP_LOW[3] = { 0x3A, 0x38, 0x2C };

#define LM87_REG_TEMP_HW_INT_LOCK       0x13
#define LM87_REG_TEMP_HW_EXT_LOCK       0x14
#define LM87_REG_TEMP_HW_INT            0x17
#define LM87_REG_TEMP_HW_EXT            0x18

/* nr in 0..1 */
#define LM87_REG_FAN(nr)                (0x28 + (nr))
#define LM87_REG_FAN_MIN(nr)            (0x3B + (nr))
#define LM87_REG_AOUT                   0x19

#define LM87_REG_CONFIG                 0x40
#define LM87_REG_CHANNEL_MODE           0x16
#define LM87_REG_VID_FAN_DIV            0x47
#define LM87_REG_VID4                   0x49

#define LM87_REG_ALARMS1                0x41
#define LM87_REG_ALARMS2                0x42

#define LM87_REG_COMPANY_ID             0x3E
#define LM87_REG_REVISION               0x3F

/*
 * Conversions and various macros
 * The LM87 uses signed 8-bit values for temperatures.
 */

#define IN_FROM_REG(reg,scale)  (((reg) * (scale) + 96) / 192)
#define IN_TO_REG(val,scale)    ((val) <= 0 ? 0 : \
                                 (val) * 192 >= (scale) * 255 ? 255 : \
                                 ((val) * 192 + (scale)/2) / (scale))

#define TEMP_FROM_REG(reg)      ((reg) * 1000)
#define TEMP_TO_REG(val)        ((val) <= -127500 ? -128 : \
                                 (val) >= 126500 ? 127 : \
                                 (((val) < 0 ? (val)-500 : (val)+500) / 1000))

#define FAN_FROM_REG(reg,div)   ((reg) == 255 || (reg) == 0 ? 0 : \
                                 1350000 + (reg)*(div) / 2) / ((reg)*(div))
#define FAN_TO_REG(val,div)     ((val)*(div) * 255 <= 1350000 ? 255 : \
                                 (1350000 + (val)*(div) / 2) / ((val)*(div)))

#define FAN_DIV_FROM_REG(reg)   (1 << (reg))

/* analog out is 9.80mV/LSB */
#define AOUT_FROM_REG(reg)      (((reg) * 98 + 5) / 10)
#define AOUT_TO_REG(val)        ((val) <= 0 ? 0 : \
                                 (val) >= 2500 ? 255 : \
                                 ((val) * 10 + 49) / 98)

/* nr in 0..1 */
#define CHAN_NO_FAN(nr)         (1 << (nr))
#define CHAN_TEMP3              (1 << 2)
#define CHAN_VCC_5V             (1 << 3)
#define CHAN_NO_VID             (1 << 8)

/*
 * Functions declaration
 */

static int lm87_attach_adapter(struct i2c_adapter *adapter);
static int lm87_detect(struct i2c_adapter *adapter, int address, int kind);
static void lm87_init_client(struct i2c_client *client);
static int lm87_detach_client(struct i2c_client *client);
static struct lm87_data *lm87_update_device(struct device *dev);

/*
 * Driver data (common to all clients)
 */

static struct i2c_driver lm87_driver = {
        .driver = {
                .name   = "lm87",
        },
        .id             = I2C_DRIVERID_LM87,
        .attach_adapter = lm87_attach_adapter,
        .detach_client  = lm87_detach_client,
};

/*
 * Client data (each client gets its own)
 */

struct lm87_data {
        struct i2c_client client;
        struct class_device *class_dev;
        struct mutex update_lock;
        char valid; /* zero until following fields are valid */
        unsigned long last_updated; /* In jiffies */

        u8 channel;             /* register value */

        u8 in[8];               /* register value */
        u8 in_max[8];           /* register value */
        u8 in_min[8];           /* register value */
        u16 in_scale[8];

        s8 temp[3];             /* register value */
        s8 temp_high[3];        /* register value */
        s8 temp_low[3];         /* register value */
        s8 temp_crit_int;       /* min of two register values */
        s8 temp_crit_ext;       /* min of two register values */

        u8 fan[2];              /* register value */
        u8 fan_min[2];          /* register value */
        u8 fan_div[2];          /* register value, shifted right */
        u8 aout;                /* register value */

        u16 alarms;             /* register values, combined */
        u8 vid;                 /* register values, combined */
        u8 vrm;
};

/*
 * Sysfs stuff
 */

static inline int lm87_read_value(struct i2c_client *client, u8 reg)
{
        return i2c_smbus_read_byte_data(client, reg);
}

static inline int lm87_write_value(struct i2c_client *client, u8 reg, u8 value)
{
        return i2c_smbus_write_byte_data(client, reg, value);
}

#define show_in(offset) \
static ssize_t show_in##offset##_input(struct device *dev, struct device_attribute *attr, char *buf) \
{ \
        struct lm87_data *data = lm87_update_device(dev); \
        return sprintf(buf, "%u\n", IN_FROM_REG(data->in[offset], \
                       data->in_scale[offset])); \
} \
static ssize_t show_in##offset##_min(struct device *dev, struct device_attribute *attr, char *buf) \
{ \
        struct lm87_data *data = lm87_update_device(dev); \
        return sprintf(buf, "%u\n", IN_FROM_REG(data->in_min[offset], \
                       data->in_scale[offset])); \
} \
static ssize_t show_in##offset##_max(struct device *dev, struct device_attribute *attr, char *buf) \
{ \
        struct lm87_data *data = lm87_update_device(dev); \
        return sprintf(buf, "%u\n", IN_FROM_REG(data->in_max[offset], \
                       data->in_scale[offset])); \
} \
static DEVICE_ATTR(in##offset##_input, S_IRUGO, \
                show_in##offset##_input, NULL);
show_in(0);
show_in(1);
show_in(2);
show_in(3);
show_in(4);
show_in(5);
show_in(6);
show_in(7);

static void set_in_min(struct device *dev, const char *buf, int nr)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct lm87_data *data = i2c_get_clientdata(client);
        long val = simple_strtol(buf, NULL, 10);

        mutex_lock(&data->update_lock);
        data->in_min[nr] = IN_TO_REG(val, data->in_scale[nr]);
        lm87_write_value(client, nr<6 ? LM87_REG_IN_MIN(nr) :
                         LM87_REG_AIN_MIN(nr-6), data->in_min[nr]);
        mutex_unlock(&data->update_lock);
}

static void set_in_max(struct device *dev, const char *buf, int nr)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct lm87_data *data = i2c_get_clientdata(client);
        long val = simple_strtol(buf, NULL, 10);

        mutex_lock(&data->update_lock);
        data->in_max[nr] = IN_TO_REG(val, data->in_scale[nr]);
        lm87_write_value(client, nr<6 ? LM87_REG_IN_MAX(nr) :
                         LM87_REG_AIN_MAX(nr-6), data->in_max[nr]);
        mutex_unlock(&data->update_lock);
}

#define set_in(offset) \
static ssize_t set_in##offset##_min(struct device *dev, struct device_attribute *attr, \
                const char *buf, size_t count) \
{ \
        set_in_min(dev, buf, offset); \
        return count; \
} \
static ssize_t set_in##offset##_max(struct device *dev, struct device_attribute *attr, \
                const char *buf, size_t count) \
{ \
        set_in_max(dev, buf, offset); \
        return count; \
} \
static DEVICE_ATTR(in##offset##_min, S_IRUGO | S_IWUSR, \
                show_in##offset##_min, set_in##offset##_min); \
static DEVICE_ATTR(in##offset##_max, S_IRUGO | S_IWUSR, \
                show_in##offset##_max, set_in##offset##_max);
set_in(0);
set_in(1);
set_in(2);
set_in(3);
set_in(4);
set_in(5);
set_in(6);
set_in(7);

#define show_temp(offset) \
static ssize_t show_temp##offset##_input(struct device *dev, struct device_attribute *attr, char *buf) \
{ \
        struct lm87_data *data = lm87_update_device(dev); \
        return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[offset-1])); \
} \
static ssize_t show_temp##offset##_low(struct device *dev, struct device_attribute *attr, char *buf) \
{ \
        struct lm87_data *data = lm87_update_device(dev); \
        return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_low[offset-1])); \
} \
static ssize_t show_temp##offset##_high(struct device *dev, struct device_attribute *attr, char *buf) \
{ \
        struct lm87_data *data = lm87_update_device(dev); \
        return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_high[offset-1])); \
}\
static DEVICE_ATTR(temp##offset##_input, S_IRUGO, \
                show_temp##offset##_input, NULL);
show_temp(1);
show_temp(2);
show_temp(3);

static void set_temp_low(struct device *dev, const char *buf, int nr)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct lm87_data *data = i2c_get_clientdata(client);
        long val = simple_strtol(buf, NULL, 10);

        mutex_lock(&data->update_lock);
        data->temp_low[nr] = TEMP_TO_REG(val);
        lm87_write_value(client, LM87_REG_TEMP_LOW[nr], data->temp_low[nr]);
        mutex_unlock(&data->update_lock);
}

static void set_temp_high(struct device *dev, const char *buf, int nr)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct lm87_data *data = i2c_get_clientdata(client);
        long val = simple_strtol(buf, NULL, 10);

        mutex_lock(&data->update_lock);
        data->temp_high[nr] = TEMP_TO_REG(val);
        lm87_write_value(client, LM87_REG_TEMP_HIGH[nr], data->temp_high[nr]);
        mutex_unlock(&data->update_lock);
}

#define set_temp(offset) \
static ssize_t set_temp##offset##_low(struct device *dev, struct device_attribute *attr, \
                const char *buf, size_t count) \
{ \
        set_temp_low(dev, buf, offset-1); \
        return count; \
} \
static ssize_t set_temp##offset##_high(struct device *dev, struct device_attribute *attr, \
                const char *buf, size_t count) \
{ \
        set_temp_high(dev, buf, offset-1); \
        return count; \
} \
static DEVICE_ATTR(temp##offset##_max, S_IRUGO | S_IWUSR, \
                show_temp##offset##_high, set_temp##offset##_high); \
static DEVICE_ATTR(temp##offset##_min, S_IRUGO | S_IWUSR, \
                show_temp##offset##_low, set_temp##offset##_low);
set_temp(1);
set_temp(2);
set_temp(3);

static ssize_t show_temp_crit_int(struct device *dev, struct device_attribute *attr, char *buf)
{
        struct lm87_data *data = lm87_update_device(dev);
        return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_crit_int));
}

static ssize_t show_temp_crit_ext(struct device *dev, struct device_attribute *attr, char *buf)
{
        struct lm87_data *data = lm87_update_device(dev);
        return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_crit_ext));
}

static DEVICE_ATTR(temp1_crit, S_IRUGO, show_temp_crit_int, NULL);
static DEVICE_ATTR(temp2_crit, S_IRUGO, show_temp_crit_ext, NULL);
static DEVICE_ATTR(temp3_crit, S_IRUGO, show_temp_crit_ext, NULL);

#define show_fan(offset) \
static ssize_t show_fan##offset##_input(struct device *dev, struct device_attribute *attr, char *buf) \
{ \
        struct lm87_data *data = lm87_update_device(dev); \
        return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan[offset-1], \
                       FAN_DIV_FROM_REG(data->fan_div[offset-1]))); \
} \
static ssize_t show_fan##offset##_min(struct device *dev, struct device_attribute *attr, char *buf) \
{ \
        struct lm87_data *data = lm87_update_device(dev); \
        return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan_min[offset-1], \
                       FAN_DIV_FROM_REG(data->fan_div[offset-1]))); \
} \
static ssize_t show_fan##offset##_div(struct device *dev, struct device_attribute *attr, char *buf) \
{ \
        struct lm87_data *data = lm87_update_device(dev); \
        return sprintf(buf, "%d\n", FAN_DIV_FROM_REG(data->fan_div[offset-1])); \
} \
static DEVICE_ATTR(fan##offset##_input, S_IRUGO, \
                show_fan##offset##_input, NULL);
show_fan(1);
show_fan(2);

static void set_fan_min(struct device *dev, const char *buf, int nr)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct lm87_data *data = i2c_get_clientdata(client);
        long val = simple_strtol(buf, NULL, 10);

        mutex_lock(&data->update_lock);
        data->fan_min[nr] = FAN_TO_REG(val,
                            FAN_DIV_FROM_REG(data->fan_div[nr]));
        lm87_write_value(client, LM87_REG_FAN_MIN(nr), data->fan_min[nr]);
        mutex_unlock(&data->update_lock);
}

/* Note: we save and restore the fan minimum here, because its value is
   determined in part by the fan clock divider.  This follows the principle
   of least surprise; the user doesn't expect the fan minimum to change just
   because the divider changed. */
static ssize_t set_fan_div(struct device *dev, const char *buf,
                size_t count, int nr)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct lm87_data *data = i2c_get_clientdata(client);
        long val = simple_strtol(buf, NULL, 10);
        unsigned long min;
        u8 reg;

        mutex_lock(&data->update_lock);
        min = FAN_FROM_REG(data->fan_min[nr],
                           FAN_DIV_FROM_REG(data->fan_div[nr]));

        switch (val) {
        case 1: data->fan_div[nr] = 0; break;
        case 2: data->fan_div[nr] = 1; break;
        case 4: data->fan_div[nr] = 2; break;
        case 8: data->fan_div[nr] = 3; break;
        default:
                mutex_unlock(&data->update_lock);
                return -EINVAL;
        }

        reg = lm87_read_value(client, LM87_REG_VID_FAN_DIV);
        switch (nr) {
        case 0:
            reg = (reg & 0xCF) | (data->fan_div[0] << 4);
            break;
        case 1:
            reg = (reg & 0x3F) | (data->fan_div[1] << 6);
            break;
        }
        lm87_write_value(client, LM87_REG_VID_FAN_DIV, reg);

        data->fan_min[nr] = FAN_TO_REG(min, val);
        lm87_write_value(client, LM87_REG_FAN_MIN(nr),
                         data->fan_min[nr]);
        mutex_unlock(&data->update_lock);

        return count;
}

#define set_fan(offset) \
static ssize_t set_fan##offset##_min(struct device *dev, struct device_attribute *attr, const char *buf, \
                size_t count) \
{ \
        set_fan_min(dev, buf, offset-1); \
        return count; \
} \
static ssize_t set_fan##offset##_div(struct device *dev, struct device_attribute *attr, const char *buf, \
                size_t count) \
{ \
        return set_fan_div(dev, buf, count, offset-1); \
} \
static DEVICE_ATTR(fan##offset##_min, S_IRUGO | S_IWUSR, \
                show_fan##offset##_min, set_fan##offset##_min); \
static DEVICE_ATTR(fan##offset##_div, S_IRUGO | S_IWUSR, \
                show_fan##offset##_div, set_fan##offset##_div);
set_fan(1);
set_fan(2);

static ssize_t show_alarms(struct device *dev, struct device_attribute *attr, char *buf)
{
        struct lm87_data *data = lm87_update_device(dev);
        return sprintf(buf, "%d\n", data->alarms);
}
static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);

static ssize_t show_vid(struct device *dev, struct device_attribute *attr, char *buf)
{
        struct lm87_data *data = lm87_update_device(dev);
        return sprintf(buf, "%d\n", vid_from_reg(data->vid, data->vrm));
}
static DEVICE_ATTR(cpu0_vid, S_IRUGO, show_vid, NULL);

static ssize_t show_vrm(struct device *dev, struct device_attribute *attr, char *buf)
{
        struct lm87_data *data = lm87_update_device(dev);
        return sprintf(buf, "%d\n", data->vrm);
}
static ssize_t set_vrm(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct lm87_data *data = i2c_get_clientdata(client);
        data->vrm = simple_strtoul(buf, NULL, 10);
        return count;
}
static DEVICE_ATTR(vrm, S_IRUGO | S_IWUSR, show_vrm, set_vrm);

static ssize_t show_aout(struct device *dev, struct device_attribute *attr, char *buf)
{
        struct lm87_data *data = lm87_update_device(dev);
        return sprintf(buf, "%d\n", AOUT_FROM_REG(data->aout));
}
static ssize_t set_aout(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct lm87_data *data = i2c_get_clientdata(client);
        long val = simple_strtol(buf, NULL, 10);

        mutex_lock(&data->update_lock);
        data->aout = AOUT_TO_REG(val);
        lm87_write_value(client, LM87_REG_AOUT, data->aout);
        mutex_unlock(&data->update_lock);
        return count;
}
static DEVICE_ATTR(aout_output, S_IRUGO | S_IWUSR, show_aout, set_aout);

/*
 * Real code
 */

static int lm87_attach_adapter(struct i2c_adapter *adapter)
{
        if (!(adapter->class & I2C_CLASS_HWMON))
                return 0;
        return i2c_probe(adapter, &addr_data, lm87_detect);
}

static struct attribute *lm87_attributes[] = {
        &dev_attr_in1_input.attr,
        &dev_attr_in1_min.attr,
        &dev_attr_in1_max.attr,
        &dev_attr_in2_input.attr,
        &dev_attr_in2_min.attr,
        &dev_attr_in2_max.attr,
        &dev_attr_in3_input.attr,
        &dev_attr_in3_min.attr,
        &dev_attr_in3_max.attr,
        &dev_attr_in4_input.attr,
        &dev_attr_in4_min.attr,
        &dev_attr_in4_max.attr,

        &dev_attr_temp1_input.attr,
        &dev_attr_temp1_max.attr,
        &dev_attr_temp1_min.attr,
        &dev_attr_temp1_crit.attr,
        &dev_attr_temp2_input.attr,
        &dev_attr_temp2_max.attr,
        &dev_attr_temp2_min.attr,
        &dev_attr_temp2_crit.attr,

        &dev_attr_alarms.attr,
        &dev_attr_aout_output.attr,

        NULL
};

static const struct attribute_group lm87_group = {
        .attrs = lm87_attributes,
};

static struct attribute *lm87_attributes_opt[] = {
        &dev_attr_in6_input.attr,
        &dev_attr_in6_min.attr,
        &dev_attr_in6_max.attr,

        &dev_attr_fan1_input.attr,
        &dev_attr_fan1_min.attr,
        &dev_attr_fan1_div.attr,

        &dev_attr_in7_input.attr,
        &dev_attr_in7_min.attr,
        &dev_attr_in7_max.attr,

        &dev_attr_fan2_input.attr,
        &dev_attr_fan2_min.attr,
        &dev_attr_fan2_div.attr,

        &dev_attr_temp3_input.attr,
        &dev_attr_temp3_max.attr,
        &dev_attr_temp3_min.attr,
        &dev_attr_temp3_crit.attr,

        &dev_attr_in0_input.attr,
        &dev_attr_in0_min.attr,
        &dev_attr_in0_max.attr,
        &dev_attr_in5_input.attr,
        &dev_attr_in5_min.attr,
        &dev_attr_in5_max.attr,

        &dev_attr_cpu0_vid.attr,
        &dev_attr_vrm.attr,

        NULL
};

static const struct attribute_group lm87_group_opt = {
        .attrs = lm87_attributes_opt,
};

/*
 * The following function does more than just detection. If detection
 * succeeds, it also registers the new chip.
 */
static int lm87_detect(struct i2c_adapter *adapter, int address, int kind)
{
        struct i2c_client *new_client;
        struct lm87_data *data;
        int err = 0;

        if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
                goto exit;

        if (!(data = kzalloc(sizeof(struct lm87_data), GFP_KERNEL))) {
                err = -ENOMEM;
                goto exit;
        }

        /* The common I2C client data is placed right before the
           LM87-specific data. */
        new_client = &data->client;
        i2c_set_clientdata(new_client, data);
        new_client->addr = address;
        new_client->adapter = adapter;
        new_client->driver = &lm87_driver;
        new_client->flags = 0;

        /* Default to an LM87 if forced */
        if (kind == 0)
                kind = lm87;

        /* Now, we do the remaining detection. */
        if (kind < 0) {
                u8 rev = lm87_read_value(new_client, LM87_REG_REVISION);

                if (rev < 0x01 || rev > 0x08
                 || (lm87_read_value(new_client, LM87_REG_CONFIG) & 0x80)
                 || lm87_read_value(new_client, LM87_REG_COMPANY_ID) != 0x02) {
                        dev_dbg(&adapter->dev,
                                "LM87 detection failed at 0x%02x.\n",
                                address);
                        goto exit_free;
                }
        }

        /* We can fill in the remaining client fields */
        strlcpy(new_client->name, "lm87", I2C_NAME_SIZE);
        data->valid = 0;
        mutex_init(&data->update_lock);

        /* Tell the I2C layer a new client has arrived */
        if ((err = i2c_attach_client(new_client)))
                goto exit_free;

        /* Initialize the LM87 chip */
        lm87_init_client(new_client);

        data->in_scale[0] = 2500;
        data->in_scale[1] = 2700;
        data->in_scale[2] = (data->channel & CHAN_VCC_5V) ? 5000 : 3300;
        data->in_scale[3] = 5000;
        data->in_scale[4] = 12000;
        data->in_scale[5] = 2700;
        data->in_scale[6] = 1875;
        data->in_scale[7] = 1875;

        /* Register sysfs hooks */
        if ((err = sysfs_create_group(&new_client->dev.kobj, &lm87_group)))
                goto exit_detach;

        if (data->channel & CHAN_NO_FAN(0)) {
                if ((err = device_create_file(&new_client->dev,
                                        &dev_attr_in6_input))
                 || (err = device_create_file(&new_client->dev,
                                        &dev_attr_in6_min))
                 || (err = device_create_file(&new_client->dev,
                                        &dev_attr_in6_max)))
                        goto exit_remove;
        } else {
                if ((err = device_create_file(&new_client->dev,
                                        &dev_attr_fan1_input))
                 || (err = device_create_file(&new_client->dev,
                                        &dev_attr_fan1_min))
                 || (err = device_create_file(&new_client->dev,
                                        &dev_attr_fan1_div)))
                        goto exit_remove;
        }

        if (data->channel & CHAN_NO_FAN(1)) {
                if ((err = device_create_file(&new_client->dev,
                                        &dev_attr_in7_input))
                 || (err = device_create_file(&new_client->dev,
                                        &dev_attr_in7_min))
                 || (err = device_create_file(&new_client->dev,
                                        &dev_attr_in7_max)))
                        goto exit_remove;
        } else {
                if ((err = device_create_file(&new_client->dev,
                                        &dev_attr_fan2_input))
                 || (err = device_create_file(&new_client->dev,
                                        &dev_attr_fan2_min))
                 || (err = device_create_file(&new_client->dev,
                                        &dev_attr_fan2_div)))
                        goto exit_remove;
        }

        if (data->channel & CHAN_TEMP3) {
                if ((err = device_create_file(&new_client->dev,
                                        &dev_attr_temp3_input))
                 || (err = device_create_file(&new_client->dev,
                                        &dev_attr_temp3_max))
                 || (err = device_create_file(&new_client->dev,
                                        &dev_attr_temp3_min))
                 || (err = device_create_file(&new_client->dev,
                                        &dev_attr_temp3_crit)))
                        goto exit_remove;
        } else {
                if ((err = device_create_file(&new_client->dev,
                                        &dev_attr_in0_input))
                 || (err = device_create_file(&new_client->dev,
                                        &dev_attr_in0_min))
                 || (err = device_create_file(&new_client->dev,
                                        &dev_attr_in0_max))
                 || (err = device_create_file(&new_client->dev,
                                        &dev_attr_in5_input))
                 || (err = device_create_file(&new_client->dev,
                                        &dev_attr_in5_min))
                 || (err = device_create_file(&new_client->dev,
                                        &dev_attr_in5_max)))
                        goto exit_remove;
        }

        if (!(data->channel & CHAN_NO_VID)) {
                data->vrm = vid_which_vrm();
                if ((err = device_create_file(&new_client->dev,
                                        &dev_attr_cpu0_vid))
                 || (err = device_create_file(&new_client->dev,
                                        &dev_attr_vrm)))
                        goto exit_remove;
        }

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

        return 0;

exit_remove:
        sysfs_remove_group(&new_client->dev.kobj, &lm87_group);
        sysfs_remove_group(&new_client->dev.kobj, &lm87_group_opt);
exit_detach:
        i2c_detach_client(new_client);
exit_free:
        kfree(data);
exit:
        return err;
}

static void lm87_init_client(struct i2c_client *client)
{
        struct lm87_data *data = i2c_get_clientdata(client);
        u8 config;

        data->channel = lm87_read_value(client, LM87_REG_CHANNEL_MODE);

        config = lm87_read_value(client, LM87_REG_CONFIG);
        if (!(config & 0x01)) {
                int i;

                /* Limits are left uninitialized after power-up */
                for (i = 1; i < 6; i++) {
                        lm87_write_value(client, LM87_REG_IN_MIN(i), 0x00);
                        lm87_write_value(client, LM87_REG_IN_MAX(i), 0xFF);
                }
                for (i = 0; i < 2; i++) {
                        lm87_write_value(client, LM87_REG_TEMP_HIGH[i], 0x7F);
                        lm87_write_value(client, LM87_REG_TEMP_LOW[i], 0x00);
                        lm87_write_value(client, LM87_REG_AIN_MIN(i), 0x00);
                        lm87_write_value(client, LM87_REG_AIN_MAX(i), 0xFF);
                }
                if (data->channel & CHAN_TEMP3) {
                        lm87_write_value(client, LM87_REG_TEMP_HIGH[2], 0x7F);
                        lm87_write_value(client, LM87_REG_TEMP_LOW[2], 0x00);
                } else {
                        lm87_write_value(client, LM87_REG_IN_MIN(0), 0x00);
                        lm87_write_value(client, LM87_REG_IN_MAX(0), 0xFF);
                }
        }
        if ((config & 0x81) != 0x01) {
                /* Start monitoring */
                lm87_write_value(client, LM87_REG_CONFIG,
                                 (config & 0xF7) | 0x01);
        }
}

static int lm87_detach_client(struct i2c_client *client)
{
        struct lm87_data *data = i2c_get_clientdata(client);
        int err;

        hwmon_device_unregister(data->class_dev);
        sysfs_remove_group(&client->dev.kobj, &lm87_group);
        sysfs_remove_group(&client->dev.kobj, &lm87_group_opt);

        if ((err = i2c_detach_client(client)))
                return err;

        kfree(data);
        return 0;
}

static struct lm87_data *lm87_update_device(struct device *dev)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct lm87_data *data = i2c_get_clientdata(client);

        mutex_lock(&data->update_lock);

        if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
                int i, j;

                dev_dbg(&client->dev, "Updating data.\n");

                i = (data->channel & CHAN_TEMP3) ? 1 : 0;
                j = (data->channel & CHAN_TEMP3) ? 5 : 6;
                for (; i < j; i++) {
                        data->in[i] = lm87_read_value(client,
                                      LM87_REG_IN(i));
                        data->in_min[i] = lm87_read_value(client,
                                          LM87_REG_IN_MIN(i));
                        data->in_max[i] = lm87_read_value(client,
                                          LM87_REG_IN_MAX(i));
                }

                for (i = 0; i < 2; i++) {
                        if (data->channel & CHAN_NO_FAN(i)) {
                                data->in[6+i] = lm87_read_value(client,
                                                LM87_REG_AIN(i));
                                data->in_max[6+i] = lm87_read_value(client,
                                                    LM87_REG_AIN_MAX(i));
                                data->in_min[6+i] = lm87_read_value(client,
                                                    LM87_REG_AIN_MIN(i));

                        } else {
                                data->fan[i] = lm87_read_value(client,
                                               LM87_REG_FAN(i));
                                data->fan_min[i] = lm87_read_value(client,
                                                   LM87_REG_FAN_MIN(i));
                        }
                }

                j = (data->channel & CHAN_TEMP3) ? 3 : 2;
                for (i = 0 ; i < j; i++) {
                        data->temp[i] = lm87_read_value(client,
                                        LM87_REG_TEMP[i]);
                        data->temp_high[i] = lm87_read_value(client,
                                             LM87_REG_TEMP_HIGH[i]);
                        data->temp_low[i] = lm87_read_value(client,
                                            LM87_REG_TEMP_LOW[i]);
                }

                i = lm87_read_value(client, LM87_REG_TEMP_HW_INT_LOCK);
                j = lm87_read_value(client, LM87_REG_TEMP_HW_INT);
                data->temp_crit_int = min(i, j);

                i = lm87_read_value(client, LM87_REG_TEMP_HW_EXT_LOCK);
                j = lm87_read_value(client, LM87_REG_TEMP_HW_EXT);
                data->temp_crit_ext = min(i, j);

                i = lm87_read_value(client, LM87_REG_VID_FAN_DIV);
                data->fan_div[0] = (i >> 4) & 0x03;
                data->fan_div[1] = (i >> 6) & 0x03;
                data->vid = (i & 0x0F)
                          | (lm87_read_value(client, LM87_REG_VID4) & 0x01)
                             << 4;

                data->alarms = lm87_read_value(client, LM87_REG_ALARMS1)
                             | (lm87_read_value(client, LM87_REG_ALARMS2)
                                << 8);
                data->aout = lm87_read_value(client, LM87_REG_AOUT);

                data->last_updated = jiffies;
                data->valid = 1;
        }

        mutex_unlock(&data->update_lock);

        return data;
}

static int __init sensors_lm87_init(void)
{
        return i2c_add_driver(&lm87_driver);
}

static void __exit sensors_lm87_exit(void)
{
        i2c_del_driver(&lm87_driver);
}

MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org> and others");
MODULE_DESCRIPTION("LM87 driver");
MODULE_LICENSE("GPL");

module_init(sensors_lm87_init);
module_exit(sensors_lm87_exit);