Initial import

1 files changed, 1047 insertions, 0 deletions

diff --git a/drivers/hwmon/lm78.c b/drivers/hwmon/lm78.c
new file mode 100644
index 000000000..539efe4ad
--- /dev/null
+++ b/drivers/hwmon/lm78.c
@@ -0,0 +1,1047 @@
+/*
+ * lm78.c - Part of lm_sensors, Linux kernel modules for hardware
+ *	    monitoring
+ * Copyright (c) 1998, 1999  Frodo Looijaard <frodol@dds.nl>
+ * Copyright (c) 2007, 2011  Jean Delvare <jdelvare@suse.de>
+ *
+ * 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.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#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/hwmon-sysfs.h>
+#include <linux/err.h>
+#include <linux/mutex.h>
+
+#ifdef CONFIG_ISA
+#include <linux/platform_device.h>
+#include <linux/ioport.h>
+#include <linux/io.h>
+#endif
+
+/* Addresses to scan */
+static const unsigned short normal_i2c[] = { 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d,
+						0x2e, 0x2f, I2C_CLIENT_END };
+enum chips { lm78, lm79 };
+
+/* Many LM78 constants specified below */
+
+/* Length of ISA address segment */
+#define LM78_EXTENT 8
+
+/* Where are the ISA address/data registers relative to the base address */
+#define LM78_ADDR_REG_OFFSET 5
+#define LM78_DATA_REG_OFFSET 6
+
+/* The LM78 registers */
+#define LM78_REG_IN_MAX(nr) (0x2b + (nr) * 2)
+#define LM78_REG_IN_MIN(nr) (0x2c + (nr) * 2)
+#define LM78_REG_IN(nr) (0x20 + (nr))
+
+#define LM78_REG_FAN_MIN(nr) (0x3b + (nr))
+#define LM78_REG_FAN(nr) (0x28 + (nr))
+
+#define LM78_REG_TEMP 0x27
+#define LM78_REG_TEMP_OVER 0x39
+#define LM78_REG_TEMP_HYST 0x3a
+
+#define LM78_REG_ALARM1 0x41
+#define LM78_REG_ALARM2 0x42
+
+#define LM78_REG_VID_FANDIV 0x47
+
+#define LM78_REG_CONFIG 0x40
+#define LM78_REG_CHIPID 0x49
+#define LM78_REG_I2C_ADDR 0x48
+
+
+/*
+ * Conversions. Rounding and limit checking is only done on the TO_REG
+ * variants.
+ */
+
+/*
+ * IN: mV (0V to 4.08V)
+ * REG: 16mV/bit
+ */
+static inline u8 IN_TO_REG(unsigned long val)
+{
+	unsigned long nval = clamp_val(val, 0, 4080);
+	return (nval + 8) / 16;
+}
+#define IN_FROM_REG(val) ((val) *  16)
+
+static inline u8 FAN_TO_REG(long rpm, int div)
+{
+	if (rpm <= 0)
+		return 255;
+	if (rpm > 1350000)
+		return 1;
+	return clamp_val((1350000 + rpm * div / 2) / (rpm * div), 1, 254);
+}
+
+static inline int FAN_FROM_REG(u8 val, int div)
+{
+	return val == 0 ? -1 : val == 255 ? 0 : 1350000 / (val * div);
+}
+
+/*
+ * TEMP: mC (-128C to +127C)
+ * REG: 1C/bit, two's complement
+ */
+static inline s8 TEMP_TO_REG(long val)
+{
+	int nval = clamp_val(val, -128000, 127000) ;
+	return nval < 0 ? (nval - 500) / 1000 : (nval + 500) / 1000;
+}
+
+static inline int TEMP_FROM_REG(s8 val)
+{
+	return val * 1000;
+}
+
+#define DIV_FROM_REG(val) (1 << (val))
+
+struct lm78_data {
+	struct i2c_client *client;
+	struct mutex lock;
+	enum chips type;
+
+	/* For ISA device only */
+	const char *name;
+	int isa_addr;
+
+	struct mutex update_lock;
+	char valid;		/* !=0 if following fields are valid */
+	unsigned long last_updated;	/* In jiffies */
+
+	u8 in[7];		/* Register value */
+	u8 in_max[7];		/* Register value */
+	u8 in_min[7];		/* Register value */
+	u8 fan[3];		/* Register value */
+	u8 fan_min[3];		/* Register value */
+	s8 temp;		/* Register value */
+	s8 temp_over;		/* Register value */
+	s8 temp_hyst;		/* Register value */
+	u8 fan_div[3];		/* Register encoding, shifted right */
+	u8 vid;			/* Register encoding, combined */
+	u16 alarms;		/* Register encoding, combined */
+};
+
+
+static int lm78_read_value(struct lm78_data *data, u8 reg);
+static int lm78_write_value(struct lm78_data *data, u8 reg, u8 value);
+static struct lm78_data *lm78_update_device(struct device *dev);
+static void lm78_init_device(struct lm78_data *data);
+
+
+/* 7 Voltages */
+static ssize_t show_in(struct device *dev, struct device_attribute *da,
+		       char *buf)
+{
+	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+	struct lm78_data *data = lm78_update_device(dev);
+	return sprintf(buf, "%d\n", IN_FROM_REG(data->in[attr->index]));
+}
+
+static ssize_t show_in_min(struct device *dev, struct device_attribute *da,
+			   char *buf)
+{
+	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+	struct lm78_data *data = lm78_update_device(dev);
+	return sprintf(buf, "%d\n", IN_FROM_REG(data->in_min[attr->index]));
+}
+
+static ssize_t show_in_max(struct device *dev, struct device_attribute *da,
+			   char *buf)
+{
+	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+	struct lm78_data *data = lm78_update_device(dev);
+	return sprintf(buf, "%d\n", IN_FROM_REG(data->in_max[attr->index]));
+}
+
+static ssize_t set_in_min(struct device *dev, struct device_attribute *da,
+			  const char *buf, size_t count)
+{
+	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+	struct lm78_data *data = dev_get_drvdata(dev);
+	int nr = attr->index;
+	unsigned long val;
+	int err;
+
+	err = kstrtoul(buf, 10, &val);
+	if (err)
+		return err;
+
+	mutex_lock(&data->update_lock);
+	data->in_min[nr] = IN_TO_REG(val);
+	lm78_write_value(data, LM78_REG_IN_MIN(nr), data->in_min[nr]);
+	mutex_unlock(&data->update_lock);
+	return count;
+}
+
+static ssize_t set_in_max(struct device *dev, struct device_attribute *da,
+			  const char *buf, size_t count)
+{
+	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+	struct lm78_data *data = dev_get_drvdata(dev);
+	int nr = attr->index;
+	unsigned long val;
+	int err;
+
+	err = kstrtoul(buf, 10, &val);
+	if (err)
+		return err;
+
+	mutex_lock(&data->update_lock);
+	data->in_max[nr] = IN_TO_REG(val);
+	lm78_write_value(data, LM78_REG_IN_MAX(nr), data->in_max[nr]);
+	mutex_unlock(&data->update_lock);
+	return count;
+}
+
+#define show_in_offset(offset)					\
+static SENSOR_DEVICE_ATTR(in##offset##_input, S_IRUGO,		\
+		show_in, NULL, offset);				\
+static SENSOR_DEVICE_ATTR(in##offset##_min, S_IRUGO | S_IWUSR,	\
+		show_in_min, set_in_min, offset);		\
+static SENSOR_DEVICE_ATTR(in##offset##_max, S_IRUGO | S_IWUSR,	\
+		show_in_max, set_in_max, offset);
+
+show_in_offset(0);
+show_in_offset(1);
+show_in_offset(2);
+show_in_offset(3);
+show_in_offset(4);
+show_in_offset(5);
+show_in_offset(6);
+
+/* Temperature */
+static ssize_t show_temp(struct device *dev, struct device_attribute *da,
+			 char *buf)
+{
+	struct lm78_data *data = lm78_update_device(dev);
+	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp));
+}
+
+static ssize_t show_temp_over(struct device *dev, struct device_attribute *da,
+			      char *buf)
+{
+	struct lm78_data *data = lm78_update_device(dev);
+	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_over));
+}
+
+static ssize_t set_temp_over(struct device *dev, struct device_attribute *da,
+			     const char *buf, size_t count)
+{
+	struct lm78_data *data = dev_get_drvdata(dev);
+	long val;
+	int err;
+
+	err = kstrtol(buf, 10, &val);
+	if (err)
+		return err;
+
+	mutex_lock(&data->update_lock);
+	data->temp_over = TEMP_TO_REG(val);
+	lm78_write_value(data, LM78_REG_TEMP_OVER, data->temp_over);
+	mutex_unlock(&data->update_lock);
+	return count;
+}
+
+static ssize_t show_temp_hyst(struct device *dev, struct device_attribute *da,
+			      char *buf)
+{
+	struct lm78_data *data = lm78_update_device(dev);
+	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_hyst));
+}
+
+static ssize_t set_temp_hyst(struct device *dev, struct device_attribute *da,
+			     const char *buf, size_t count)
+{
+	struct lm78_data *data = dev_get_drvdata(dev);
+	long val;
+	int err;
+
+	err = kstrtol(buf, 10, &val);
+	if (err)
+		return err;
+
+	mutex_lock(&data->update_lock);
+	data->temp_hyst = TEMP_TO_REG(val);
+	lm78_write_value(data, LM78_REG_TEMP_HYST, data->temp_hyst);
+	mutex_unlock(&data->update_lock);
+	return count;
+}
+
+static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL);
+static DEVICE_ATTR(temp1_max, S_IRUGO | S_IWUSR,
+		show_temp_over, set_temp_over);
+static DEVICE_ATTR(temp1_max_hyst, S_IRUGO | S_IWUSR,
+		show_temp_hyst, set_temp_hyst);
+
+/* 3 Fans */
+static ssize_t show_fan(struct device *dev, struct device_attribute *da,
+			char *buf)
+{
+	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+	struct lm78_data *data = lm78_update_device(dev);
+	int nr = attr->index;
+	return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan[nr],
+		DIV_FROM_REG(data->fan_div[nr])));
+}
+
+static ssize_t show_fan_min(struct device *dev, struct device_attribute *da,
+			    char *buf)
+{
+	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+	struct lm78_data *data = lm78_update_device(dev);
+	int nr = attr->index;
+	return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan_min[nr],
+		DIV_FROM_REG(data->fan_div[nr])));
+}
+
+static ssize_t set_fan_min(struct device *dev, struct device_attribute *da,
+			   const char *buf, size_t count)
+{
+	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+	struct lm78_data *data = dev_get_drvdata(dev);
+	int nr = attr->index;
+	unsigned long val;
+	int err;
+
+	err = kstrtoul(buf, 10, &val);
+	if (err)
+		return err;
+
+	mutex_lock(&data->update_lock);
+	data->fan_min[nr] = FAN_TO_REG(val, DIV_FROM_REG(data->fan_div[nr]));
+	lm78_write_value(data, LM78_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 *da,
+			    char *buf)
+{
+	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+	struct lm78_data *data = lm78_update_device(dev);
+	return sprintf(buf, "%d\n", DIV_FROM_REG(data->fan_div[attr->index]));
+}
+
+/*
+ * 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 set_fan_div(struct device *dev, struct device_attribute *da,
+			   const char *buf, size_t count)
+{
+	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+	struct lm78_data *data = dev_get_drvdata(dev);
+	int nr = attr->index;
+	unsigned long min;
+	u8 reg;
+	unsigned long val;
+	int err;
+
+	err = kstrtoul(buf, 10, &val);
+	if (err)
+		return err;
+
+	mutex_lock(&data->update_lock);
+	min = FAN_FROM_REG(data->fan_min[nr],
+			   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:
+		dev_err(dev,
+			"fan_div value %ld not supported. Choose one of 1, 2, 4 or 8!\n",
+			val);
+		mutex_unlock(&data->update_lock);
+		return -EINVAL;
+	}
+
+	reg = lm78_read_value(data, LM78_REG_VID_FANDIV);
+	switch (nr) {
+	case 0:
+		reg = (reg & 0xcf) | (data->fan_div[nr] << 4);
+		break;
+	case 1:
+		reg = (reg & 0x3f) | (data->fan_div[nr] << 6);
+		break;
+	}
+	lm78_write_value(data, LM78_REG_VID_FANDIV, reg);
+
+	data->fan_min[nr] =
+		FAN_TO_REG(min, DIV_FROM_REG(data->fan_div[nr]));
+	lm78_write_value(data, LM78_REG_FAN_MIN(nr), data->fan_min[nr]);
+	mutex_unlock(&data->update_lock);
+
+	return count;
+}
+
+#define show_fan_offset(offset)				\
+static SENSOR_DEVICE_ATTR(fan##offset##_input, S_IRUGO,		\
+		show_fan, NULL, offset - 1);			\
+static SENSOR_DEVICE_ATTR(fan##offset##_min, S_IRUGO | S_IWUSR,	\
+		show_fan_min, set_fan_min, offset - 1);
+
+show_fan_offset(1);
+show_fan_offset(2);
+show_fan_offset(3);
+
+/* Fan 3 divisor is locked in H/W */
+static SENSOR_DEVICE_ATTR(fan1_div, S_IRUGO | S_IWUSR,
+		show_fan_div, set_fan_div, 0);
+static SENSOR_DEVICE_ATTR(fan2_div, S_IRUGO | S_IWUSR,
+		show_fan_div, set_fan_div, 1);
+static SENSOR_DEVICE_ATTR(fan3_div, S_IRUGO, show_fan_div, NULL, 2);
+
+/* VID */
+static ssize_t show_vid(struct device *dev, struct device_attribute *da,
+			char *buf)
+{
+	struct lm78_data *data = lm78_update_device(dev);
+	return sprintf(buf, "%d\n", vid_from_reg(data->vid, 82));
+}
+static DEVICE_ATTR(cpu0_vid, S_IRUGO, show_vid, NULL);
+
+/* Alarms */
+static ssize_t show_alarms(struct device *dev, struct device_attribute *da,
+			   char *buf)
+{
+	struct lm78_data *data = lm78_update_device(dev);
+	return sprintf(buf, "%u\n", data->alarms);
+}
+static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
+
+static ssize_t show_alarm(struct device *dev, struct device_attribute *da,
+			  char *buf)
+{
+	struct lm78_data *data = lm78_update_device(dev);
+	int nr = to_sensor_dev_attr(da)->index;
+	return sprintf(buf, "%u\n", (data->alarms >> nr) & 1);
+}
+static SENSOR_DEVICE_ATTR(in0_alarm, S_IRUGO, show_alarm, NULL, 0);
+static SENSOR_DEVICE_ATTR(in1_alarm, S_IRUGO, show_alarm, NULL, 1);
+static SENSOR_DEVICE_ATTR(in2_alarm, S_IRUGO, show_alarm, NULL, 2);
+static SENSOR_DEVICE_ATTR(in3_alarm, S_IRUGO, show_alarm, NULL, 3);
+static SENSOR_DEVICE_ATTR(in4_alarm, S_IRUGO, show_alarm, NULL, 8);
+static SENSOR_DEVICE_ATTR(in5_alarm, S_IRUGO, show_alarm, NULL, 9);
+static SENSOR_DEVICE_ATTR(in6_alarm, S_IRUGO, show_alarm, NULL, 10);
+static SENSOR_DEVICE_ATTR(fan1_alarm, S_IRUGO, show_alarm, NULL, 6);
+static SENSOR_DEVICE_ATTR(fan2_alarm, S_IRUGO, show_alarm, NULL, 7);
+static SENSOR_DEVICE_ATTR(fan3_alarm, S_IRUGO, show_alarm, NULL, 11);
+static SENSOR_DEVICE_ATTR(temp1_alarm, S_IRUGO, show_alarm, NULL, 4);
+
+static struct attribute *lm78_attrs[] = {
+	&sensor_dev_attr_in0_input.dev_attr.attr,
+	&sensor_dev_attr_in0_min.dev_attr.attr,
+	&sensor_dev_attr_in0_max.dev_attr.attr,
+	&sensor_dev_attr_in0_alarm.dev_attr.attr,
+	&sensor_dev_attr_in1_input.dev_attr.attr,
+	&sensor_dev_attr_in1_min.dev_attr.attr,
+	&sensor_dev_attr_in1_max.dev_attr.attr,
+	&sensor_dev_attr_in1_alarm.dev_attr.attr,
+	&sensor_dev_attr_in2_input.dev_attr.attr,
+	&sensor_dev_attr_in2_min.dev_attr.attr,
+	&sensor_dev_attr_in2_max.dev_attr.attr,
+	&sensor_dev_attr_in2_alarm.dev_attr.attr,
+	&sensor_dev_attr_in3_input.dev_attr.attr,
+	&sensor_dev_attr_in3_min.dev_attr.attr,
+	&sensor_dev_attr_in3_max.dev_attr.attr,
+	&sensor_dev_attr_in3_alarm.dev_attr.attr,
+	&sensor_dev_attr_in4_input.dev_attr.attr,
+	&sensor_dev_attr_in4_min.dev_attr.attr,
+	&sensor_dev_attr_in4_max.dev_attr.attr,
+	&sensor_dev_attr_in4_alarm.dev_attr.attr,
+	&sensor_dev_attr_in5_input.dev_attr.attr,
+	&sensor_dev_attr_in5_min.dev_attr.attr,
+	&sensor_dev_attr_in5_max.dev_attr.attr,
+	&sensor_dev_attr_in5_alarm.dev_attr.attr,
+	&sensor_dev_attr_in6_input.dev_attr.attr,
+	&sensor_dev_attr_in6_min.dev_attr.attr,
+	&sensor_dev_attr_in6_max.dev_attr.attr,
+	&sensor_dev_attr_in6_alarm.dev_attr.attr,
+	&dev_attr_temp1_input.attr,
+	&dev_attr_temp1_max.attr,
+	&dev_attr_temp1_max_hyst.attr,
+	&sensor_dev_attr_temp1_alarm.dev_attr.attr,
+	&sensor_dev_attr_fan1_input.dev_attr.attr,
+	&sensor_dev_attr_fan1_min.dev_attr.attr,
+	&sensor_dev_attr_fan1_div.dev_attr.attr,
+	&sensor_dev_attr_fan1_alarm.dev_attr.attr,
+	&sensor_dev_attr_fan2_input.dev_attr.attr,
+	&sensor_dev_attr_fan2_min.dev_attr.attr,
+	&sensor_dev_attr_fan2_div.dev_attr.attr,
+	&sensor_dev_attr_fan2_alarm.dev_attr.attr,
+	&sensor_dev_attr_fan3_input.dev_attr.attr,
+	&sensor_dev_attr_fan3_min.dev_attr.attr,
+	&sensor_dev_attr_fan3_div.dev_attr.attr,
+	&sensor_dev_attr_fan3_alarm.dev_attr.attr,
+	&dev_attr_alarms.attr,
+	&dev_attr_cpu0_vid.attr,
+
+	NULL
+};
+
+ATTRIBUTE_GROUPS(lm78);
+
+/*
+ * ISA related code
+ */
+#ifdef CONFIG_ISA
+
+/* ISA device, if found */
+static struct platform_device *pdev;
+
+static unsigned short isa_address = 0x290;
+
+static struct lm78_data *lm78_data_if_isa(void)
+{
+	return pdev ? platform_get_drvdata(pdev) : NULL;
+}
+
+/* Returns 1 if the I2C chip appears to be an alias of the ISA chip */
+static int lm78_alias_detect(struct i2c_client *client, u8 chipid)
+{
+	struct lm78_data *isa;
+	int i;
+
+	if (!pdev)	/* No ISA chip */
+		return 0;
+	isa = platform_get_drvdata(pdev);
+
+	if (lm78_read_value(isa, LM78_REG_I2C_ADDR) != client->addr)
+		return 0;	/* Address doesn't match */
+	if ((lm78_read_value(isa, LM78_REG_CHIPID) & 0xfe) != (chipid & 0xfe))
+		return 0;	/* Chip type doesn't match */
+
+	/*
+	 * We compare all the limit registers, the config register and the
+	 * interrupt mask registers
+	 */
+	for (i = 0x2b; i <= 0x3d; i++) {
+		if (lm78_read_value(isa, i) !=
+		    i2c_smbus_read_byte_data(client, i))
+			return 0;
+	}
+	if (lm78_read_value(isa, LM78_REG_CONFIG) !=
+	    i2c_smbus_read_byte_data(client, LM78_REG_CONFIG))
+		return 0;
+	for (i = 0x43; i <= 0x46; i++) {
+		if (lm78_read_value(isa, i) !=
+		    i2c_smbus_read_byte_data(client, i))
+			return 0;
+	}
+
+	return 1;
+}
+#else /* !CONFIG_ISA */
+
+static int lm78_alias_detect(struct i2c_client *client, u8 chipid)
+{
+	return 0;
+}
+
+static struct lm78_data *lm78_data_if_isa(void)
+{
+	return NULL;
+}
+#endif /* CONFIG_ISA */
+
+static int lm78_i2c_detect(struct i2c_client *client,
+			   struct i2c_board_info *info)
+{
+	int i;
+	struct lm78_data *isa = lm78_data_if_isa();
+	const char *client_name;
+	struct i2c_adapter *adapter = client->adapter;
+	int address = client->addr;
+
+	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
+		return -ENODEV;
+
+	/*
+	 * We block updates of the ISA device to minimize the risk of
+	 * concurrent access to the same LM78 chip through different
+	 * interfaces.
+	 */
+	if (isa)
+		mutex_lock(&isa->update_lock);
+
+	if ((i2c_smbus_read_byte_data(client, LM78_REG_CONFIG) & 0x80)
+	 || i2c_smbus_read_byte_data(client, LM78_REG_I2C_ADDR) != address)
+		goto err_nodev;
+
+	/* Explicitly prevent the misdetection of Winbond chips */
+	i = i2c_smbus_read_byte_data(client, 0x4f);
+	if (i == 0xa3 || i == 0x5c)
+		goto err_nodev;
+
+	/* Determine the chip type. */
+	i = i2c_smbus_read_byte_data(client, LM78_REG_CHIPID);
+	if (i == 0x00 || i == 0x20	/* LM78 */
+	 || i == 0x40)			/* LM78-J */
+		client_name = "lm78";
+	else if ((i & 0xfe) == 0xc0)
+		client_name = "lm79";
+	else
+		goto err_nodev;
+
+	if (lm78_alias_detect(client, i)) {
+		dev_dbg(&adapter->dev,
+			"Device at 0x%02x appears to be the same as ISA device\n",
+			address);
+		goto err_nodev;
+	}
+
+	if (isa)
+		mutex_unlock(&isa->update_lock);
+
+	strlcpy(info->type, client_name, I2C_NAME_SIZE);
+
+	return 0;
+
+ err_nodev:
+	if (isa)
+		mutex_unlock(&isa->update_lock);
+	return -ENODEV;
+}
+
+static int lm78_i2c_probe(struct i2c_client *client,
+			  const struct i2c_device_id *id)
+{
+	struct device *dev = &client->dev;
+	struct device *hwmon_dev;
+	struct lm78_data *data;
+
+	data = devm_kzalloc(dev, sizeof(struct lm78_data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->client = client;
+	data->type = id->driver_data;
+
+	/* Initialize the LM78 chip */
+	lm78_init_device(data);
+
+	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
+							   data, lm78_groups);
+	return PTR_ERR_OR_ZERO(hwmon_dev);
+}
+
+static const struct i2c_device_id lm78_i2c_id[] = {
+	{ "lm78", lm78 },
+	{ "lm79", lm79 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, lm78_i2c_id);
+
+static struct i2c_driver lm78_driver = {
+	.class		= I2C_CLASS_HWMON,
+	.driver = {
+		.name	= "lm78",
+	},
+	.probe		= lm78_i2c_probe,
+	.id_table	= lm78_i2c_id,
+	.detect		= lm78_i2c_detect,
+	.address_list	= normal_i2c,
+};
+
+/*
+ * The SMBus locks itself, but ISA access must be locked explicitly!
+ * We don't want to lock the whole ISA bus, so we lock each client
+ * separately.
+ * We ignore the LM78 BUSY flag at this moment - it could lead to deadlocks,
+ * would slow down the LM78 access and should not be necessary.
+ */
+static int lm78_read_value(struct lm78_data *data, u8 reg)
+{
+	struct i2c_client *client = data->client;
+
+#ifdef CONFIG_ISA
+	if (!client) { /* ISA device */
+		int res;
+		mutex_lock(&data->lock);
+		outb_p(reg, data->isa_addr + LM78_ADDR_REG_OFFSET);
+		res = inb_p(data->isa_addr + LM78_DATA_REG_OFFSET);
+		mutex_unlock(&data->lock);
+		return res;
+	} else
+#endif
+		return i2c_smbus_read_byte_data(client, reg);
+}
+
+static int lm78_write_value(struct lm78_data *data, u8 reg, u8 value)
+{
+	struct i2c_client *client = data->client;
+
+#ifdef CONFIG_ISA
+	if (!client) { /* ISA device */
+		mutex_lock(&data->lock);
+		outb_p(reg, data->isa_addr + LM78_ADDR_REG_OFFSET);
+		outb_p(value, data->isa_addr + LM78_DATA_REG_OFFSET);
+		mutex_unlock(&data->lock);
+		return 0;
+	} else
+#endif
+		return i2c_smbus_write_byte_data(client, reg, value);
+}
+
+static void lm78_init_device(struct lm78_data *data)
+{
+	u8 config;
+	int i;
+
+	/* Start monitoring */
+	config = lm78_read_value(data, LM78_REG_CONFIG);
+	if ((config & 0x09) != 0x01)
+		lm78_write_value(data, LM78_REG_CONFIG,
+				 (config & 0xf7) | 0x01);
+
+	/* A few vars need to be filled upon startup */
+	for (i = 0; i < 3; i++) {
+		data->fan_min[i] = lm78_read_value(data,
+					LM78_REG_FAN_MIN(i));
+	}
+
+	mutex_init(&data->update_lock);
+}
+
+static struct lm78_data *lm78_update_device(struct device *dev)
+{
+	struct lm78_data *data = dev_get_drvdata(dev);
+	int i;
+
+	mutex_lock(&data->update_lock);
+
+	if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
+	    || !data->valid) {
+
+		dev_dbg(dev, "Starting lm78 update\n");
+
+		for (i = 0; i <= 6; i++) {
+			data->in[i] =
+			    lm78_read_value(data, LM78_REG_IN(i));
+			data->in_min[i] =
+			    lm78_read_value(data, LM78_REG_IN_MIN(i));
+			data->in_max[i] =
+			    lm78_read_value(data, LM78_REG_IN_MAX(i));
+		}
+		for (i = 0; i < 3; i++) {
+			data->fan[i] =
+			    lm78_read_value(data, LM78_REG_FAN(i));
+			data->fan_min[i] =
+			    lm78_read_value(data, LM78_REG_FAN_MIN(i));
+		}
+		data->temp = lm78_read_value(data, LM78_REG_TEMP);
+		data->temp_over =
+		    lm78_read_value(data, LM78_REG_TEMP_OVER);
+		data->temp_hyst =
+		    lm78_read_value(data, LM78_REG_TEMP_HYST);
+		i = lm78_read_value(data, LM78_REG_VID_FANDIV);
+		data->vid = i & 0x0f;
+		if (data->type == lm79)
+			data->vid |=
+			    (lm78_read_value(data, LM78_REG_CHIPID) &
+			     0x01) << 4;
+		else
+			data->vid |= 0x10;
+		data->fan_div[0] = (i >> 4) & 0x03;
+		data->fan_div[1] = i >> 6;
+		data->alarms = lm78_read_value(data, LM78_REG_ALARM1) +
+		    (lm78_read_value(data, LM78_REG_ALARM2) << 8);
+		data->last_updated = jiffies;
+		data->valid = 1;
+
+		data->fan_div[2] = 1;
+	}
+
+	mutex_unlock(&data->update_lock);
+
+	return data;
+}
+
+#ifdef CONFIG_ISA
+static int lm78_isa_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device *hwmon_dev;
+	struct lm78_data *data;
+	struct resource *res;
+
+	/* Reserve the ISA region */
+	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
+	if (!devm_request_region(dev, res->start + LM78_ADDR_REG_OFFSET,
+				 2, "lm78"))
+		return -EBUSY;
+
+	data = devm_kzalloc(dev, sizeof(struct lm78_data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	mutex_init(&data->lock);
+	data->isa_addr = res->start;
+	platform_set_drvdata(pdev, data);
+
+	if (lm78_read_value(data, LM78_REG_CHIPID) & 0x80) {
+		data->type = lm79;
+		data->name = "lm79";
+	} else {
+		data->type = lm78;
+		data->name = "lm78";
+	}
+
+	/* Initialize the LM78 chip */
+	lm78_init_device(data);
+
+	hwmon_dev = devm_hwmon_device_register_with_groups(dev, data->name,
+							   data, lm78_groups);
+	return PTR_ERR_OR_ZERO(hwmon_dev);
+}
+
+static struct platform_driver lm78_isa_driver = {
+	.driver = {
+		.name	= "lm78",
+	},
+	.probe		= lm78_isa_probe,
+};
+
+/* return 1 if a supported chip is found, 0 otherwise */
+static int __init lm78_isa_found(unsigned short address)
+{
+	int val, save, found = 0;
+	int port;
+
+	/*
+	 * Some boards declare base+0 to base+7 as a PNP device, some base+4
+	 * to base+7 and some base+5 to base+6. So we better request each port
+	 * individually for the probing phase.
+	 */
+	for (port = address; port < address + LM78_EXTENT; port++) {
+		if (!request_region(port, 1, "lm78")) {
+			pr_debug("Failed to request port 0x%x\n", port);
+			goto release;
+		}
+	}
+
+#define REALLY_SLOW_IO
+	/*
+	 * We need the timeouts for at least some LM78-like
+	 * chips. But only if we read 'undefined' registers.
+	 */
+	val = inb_p(address + 1);
+	if (inb_p(address + 2) != val
+	 || inb_p(address + 3) != val
+	 || inb_p(address + 7) != val)
+		goto release;
+#undef REALLY_SLOW_IO
+
+	/*
+	 * We should be able to change the 7 LSB of the address port. The
+	 * MSB (busy flag) should be clear initially, set after the write.
+	 */
+	save = inb_p(address + LM78_ADDR_REG_OFFSET);
+	if (save & 0x80)
+		goto release;
+	val = ~save & 0x7f;
+	outb_p(val, address + LM78_ADDR_REG_OFFSET);
+	if (inb_p(address + LM78_ADDR_REG_OFFSET) != (val | 0x80)) {
+		outb_p(save, address + LM78_ADDR_REG_OFFSET);
+		goto release;
+	}
+
+	/* We found a device, now see if it could be an LM78 */
+	outb_p(LM78_REG_CONFIG, address + LM78_ADDR_REG_OFFSET);
+	val = inb_p(address + LM78_DATA_REG_OFFSET);
+	if (val & 0x80)
+		goto release;
+	outb_p(LM78_REG_I2C_ADDR, address + LM78_ADDR_REG_OFFSET);
+	val = inb_p(address + LM78_DATA_REG_OFFSET);
+	if (val < 0x03 || val > 0x77)	/* Not a valid I2C address */
+		goto release;
+
+	/* The busy flag should be clear again */
+	if (inb_p(address + LM78_ADDR_REG_OFFSET) & 0x80)
+		goto release;
+
+	/* Explicitly prevent the misdetection of Winbond chips */
+	outb_p(0x4f, address + LM78_ADDR_REG_OFFSET);
+	val = inb_p(address + LM78_DATA_REG_OFFSET);
+	if (val == 0xa3 || val == 0x5c)
+		goto release;
+
+	/* Explicitly prevent the misdetection of ITE chips */
+	outb_p(0x58, address + LM78_ADDR_REG_OFFSET);
+	val = inb_p(address + LM78_DATA_REG_OFFSET);
+	if (val == 0x90)
+		goto release;
+
+	/* Determine the chip type */
+	outb_p(LM78_REG_CHIPID, address + LM78_ADDR_REG_OFFSET);
+	val = inb_p(address + LM78_DATA_REG_OFFSET);
+	if (val == 0x00 || val == 0x20	/* LM78 */
+	 || val == 0x40			/* LM78-J */
+	 || (val & 0xfe) == 0xc0)	/* LM79 */
+		found = 1;
+
+	if (found)
+		pr_info("Found an %s chip at %#x\n",
+			val & 0x80 ? "LM79" : "LM78", (int)address);
+
+ release:
+	for (port--; port >= address; port--)
+		release_region(port, 1);
+	return found;
+}
+
+static int __init lm78_isa_device_add(unsigned short address)
+{
+	struct resource res = {
+		.start	= address,
+		.end	= address + LM78_EXTENT - 1,
+		.name	= "lm78",
+		.flags	= IORESOURCE_IO,
+	};
+	int err;
+
+	pdev = platform_device_alloc("lm78", address);
+	if (!pdev) {
+		err = -ENOMEM;
+		pr_err("Device allocation failed\n");
+		goto exit;
+	}
+
+	err = platform_device_add_resources(pdev, &res, 1);
+	if (err) {
+		pr_err("Device resource addition failed (%d)\n", err);
+		goto exit_device_put;
+	}
+
+	err = platform_device_add(pdev);
+	if (err) {
+		pr_err("Device addition failed (%d)\n", err);
+		goto exit_device_put;
+	}
+
+	return 0;
+
+ exit_device_put:
+	platform_device_put(pdev);
+ exit:
+	pdev = NULL;
+	return err;
+}
+
+static int __init lm78_isa_register(void)
+{
+	int res;
+
+	if (lm78_isa_found(isa_address)) {
+		res = platform_driver_register(&lm78_isa_driver);
+		if (res)
+			goto exit;
+
+		/* Sets global pdev as a side effect */
+		res = lm78_isa_device_add(isa_address);
+		if (res)
+			goto exit_unreg_isa_driver;
+	}
+
+	return 0;
+
+ exit_unreg_isa_driver:
+	platform_driver_unregister(&lm78_isa_driver);
+ exit:
+	return res;
+}
+
+static void lm78_isa_unregister(void)
+{
+	if (pdev) {
+		platform_device_unregister(pdev);
+		platform_driver_unregister(&lm78_isa_driver);
+	}
+}
+#else /* !CONFIG_ISA */
+
+static int __init lm78_isa_register(void)
+{
+	return 0;
+}
+
+static void lm78_isa_unregister(void)
+{
+}
+#endif /* CONFIG_ISA */
+
+static int __init sm_lm78_init(void)
+{
+	int res;
+
+	/*
+	 * We register the ISA device first, so that we can skip the
+	 * registration of an I2C interface to the same device.
+	 */
+	res = lm78_isa_register();
+	if (res)
+		goto exit;
+
+	res = i2c_add_driver(&lm78_driver);
+	if (res)
+		goto exit_unreg_isa_device;
+
+	return 0;
+
+ exit_unreg_isa_device:
+	lm78_isa_unregister();
+ exit:
+	return res;
+}
+
+static void __exit sm_lm78_exit(void)
+{
+	lm78_isa_unregister();
+	i2c_del_driver(&lm78_driver);
+}
+
+MODULE_AUTHOR("Frodo Looijaard, Jean Delvare <jdelvare@suse.de>");
+MODULE_DESCRIPTION("LM78/LM79 driver");
+MODULE_LICENSE("GPL");
+
+module_init(sm_lm78_init);
+module_exit(sm_lm78_exit);