v4.19.13 snapshot.
diff --git a/drivers/hwmon/gl520sm.c b/drivers/hwmon/gl520sm.c
new file mode 100644
index 0000000..4ff32ee
--- /dev/null
+++ b/drivers/hwmon/gl520sm.c
@@ -0,0 +1,939 @@
+/*
+ * gl520sm.c - Part of lm_sensors, Linux kernel modules for hardware
+ *	       monitoring
+ * Copyright (c) 1998, 1999  Frodo Looijaard <frodol@dds.nl>,
+ *			     Kyösti Mälkki <kmalkki@cc.hut.fi>
+ * Copyright (c) 2005	Maarten Deprez <maartendeprez@users.sourceforge.net>
+ *
+ * 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-sysfs.h>
+#include <linux/hwmon-vid.h>
+#include <linux/err.h>
+#include <linux/mutex.h>
+#include <linux/sysfs.h>
+
+/* Type of the extra sensor */
+static unsigned short extra_sensor_type;
+module_param(extra_sensor_type, ushort, 0);
+MODULE_PARM_DESC(extra_sensor_type, "Type of extra sensor (0=autodetect, 1=temperature, 2=voltage)");
+
+/* Addresses to scan */
+static const unsigned short normal_i2c[] = { 0x2c, 0x2d, I2C_CLIENT_END };
+
+/*
+ * Many GL520 constants specified below
+ * One of the inputs can be configured as either temp or voltage.
+ * That's why _TEMP2 and _IN4 access the same register
+ */
+
+/* The GL520 registers */
+#define GL520_REG_CHIP_ID		0x00
+#define GL520_REG_REVISION		0x01
+#define GL520_REG_CONF			0x03
+#define GL520_REG_MASK			0x11
+
+#define GL520_REG_VID_INPUT		0x02
+
+static const u8 GL520_REG_IN_INPUT[]	= { 0x15, 0x14, 0x13, 0x0d, 0x0e };
+static const u8 GL520_REG_IN_LIMIT[]	= { 0x0c, 0x09, 0x0a, 0x0b };
+static const u8 GL520_REG_IN_MIN[]	= { 0x0c, 0x09, 0x0a, 0x0b, 0x18 };
+static const u8 GL520_REG_IN_MAX[]	= { 0x0c, 0x09, 0x0a, 0x0b, 0x17 };
+
+static const u8 GL520_REG_TEMP_INPUT[]		= { 0x04, 0x0e };
+static const u8 GL520_REG_TEMP_MAX[]		= { 0x05, 0x17 };
+static const u8 GL520_REG_TEMP_MAX_HYST[]	= { 0x06, 0x18 };
+
+#define GL520_REG_FAN_INPUT		0x07
+#define GL520_REG_FAN_MIN		0x08
+#define GL520_REG_FAN_DIV		0x0f
+#define GL520_REG_FAN_OFF		GL520_REG_FAN_DIV
+
+#define GL520_REG_ALARMS		0x12
+#define GL520_REG_BEEP_MASK		0x10
+#define GL520_REG_BEEP_ENABLE		GL520_REG_CONF
+
+/* Client data */
+struct gl520_data {
+	struct i2c_client *client;
+	const struct attribute_group *groups[3];
+	struct mutex update_lock;
+	char valid;		/* zero until the following fields are valid */
+	unsigned long last_updated;	/* in jiffies */
+
+	u8 vid;
+	u8 vrm;
+	u8 in_input[5];		/* [0] = VVD */
+	u8 in_min[5];		/* [0] = VDD */
+	u8 in_max[5];		/* [0] = VDD */
+	u8 fan_input[2];
+	u8 fan_min[2];
+	u8 fan_div[2];
+	u8 fan_off;
+	u8 temp_input[2];
+	u8 temp_max[2];
+	u8 temp_max_hyst[2];
+	u8 alarms;
+	u8 beep_enable;
+	u8 beep_mask;
+	u8 alarm_mask;
+	u8 two_temps;
+};
+
+/*
+ * Registers 0x07 to 0x0c are word-sized, others are byte-sized
+ * GL520 uses a high-byte first convention
+ */
+static int gl520_read_value(struct i2c_client *client, u8 reg)
+{
+	if ((reg >= 0x07) && (reg <= 0x0c))
+		return i2c_smbus_read_word_swapped(client, reg);
+	else
+		return i2c_smbus_read_byte_data(client, reg);
+}
+
+static int gl520_write_value(struct i2c_client *client, u8 reg, u16 value)
+{
+	if ((reg >= 0x07) && (reg <= 0x0c))
+		return i2c_smbus_write_word_swapped(client, reg, value);
+	else
+		return i2c_smbus_write_byte_data(client, reg, value);
+}
+
+static struct gl520_data *gl520_update_device(struct device *dev)
+{
+	struct gl520_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
+	int val, i;
+
+	mutex_lock(&data->update_lock);
+
+	if (time_after(jiffies, data->last_updated + 2 * HZ) || !data->valid) {
+
+		dev_dbg(&client->dev, "Starting gl520sm update\n");
+
+		data->alarms = gl520_read_value(client, GL520_REG_ALARMS);
+		data->beep_mask = gl520_read_value(client, GL520_REG_BEEP_MASK);
+		data->vid = gl520_read_value(client,
+					     GL520_REG_VID_INPUT) & 0x1f;
+
+		for (i = 0; i < 4; i++) {
+			data->in_input[i] = gl520_read_value(client,
+							GL520_REG_IN_INPUT[i]);
+			val = gl520_read_value(client, GL520_REG_IN_LIMIT[i]);
+			data->in_min[i] = val & 0xff;
+			data->in_max[i] = (val >> 8) & 0xff;
+		}
+
+		val = gl520_read_value(client, GL520_REG_FAN_INPUT);
+		data->fan_input[0] = (val >> 8) & 0xff;
+		data->fan_input[1] = val & 0xff;
+
+		val = gl520_read_value(client, GL520_REG_FAN_MIN);
+		data->fan_min[0] = (val >> 8) & 0xff;
+		data->fan_min[1] = val & 0xff;
+
+		data->temp_input[0] = gl520_read_value(client,
+						GL520_REG_TEMP_INPUT[0]);
+		data->temp_max[0] = gl520_read_value(client,
+						GL520_REG_TEMP_MAX[0]);
+		data->temp_max_hyst[0] = gl520_read_value(client,
+						GL520_REG_TEMP_MAX_HYST[0]);
+
+		val = gl520_read_value(client, GL520_REG_FAN_DIV);
+		data->fan_div[0] = (val >> 6) & 0x03;
+		data->fan_div[1] = (val >> 4) & 0x03;
+		data->fan_off = (val >> 2) & 0x01;
+
+		data->alarms &= data->alarm_mask;
+
+		val = gl520_read_value(client, GL520_REG_CONF);
+		data->beep_enable = !((val >> 2) & 1);
+
+		/* Temp1 and Vin4 are the same input */
+		if (data->two_temps) {
+			data->temp_input[1] = gl520_read_value(client,
+						GL520_REG_TEMP_INPUT[1]);
+			data->temp_max[1] = gl520_read_value(client,
+						GL520_REG_TEMP_MAX[1]);
+			data->temp_max_hyst[1] = gl520_read_value(client,
+						GL520_REG_TEMP_MAX_HYST[1]);
+		} else {
+			data->in_input[4] = gl520_read_value(client,
+						GL520_REG_IN_INPUT[4]);
+			data->in_min[4] = gl520_read_value(client,
+						GL520_REG_IN_MIN[4]);
+			data->in_max[4] = gl520_read_value(client,
+						GL520_REG_IN_MAX[4]);
+		}
+
+		data->last_updated = jiffies;
+		data->valid = 1;
+	}
+
+	mutex_unlock(&data->update_lock);
+
+	return data;
+}
+
+/*
+ * Sysfs stuff
+ */
+
+static ssize_t cpu0_vid_show(struct device *dev,
+			     struct device_attribute *attr, char *buf)
+{
+	struct gl520_data *data = gl520_update_device(dev);
+	return sprintf(buf, "%u\n", vid_from_reg(data->vid, data->vrm));
+}
+static DEVICE_ATTR_RO(cpu0_vid);
+
+#define VDD_FROM_REG(val)	DIV_ROUND_CLOSEST((val) * 95, 4)
+#define VDD_CLAMP(val)		clamp_val(val, 0, 255 * 95 / 4)
+#define VDD_TO_REG(val)		DIV_ROUND_CLOSEST(VDD_CLAMP(val) * 4, 95)
+
+#define IN_FROM_REG(val)	((val) * 19)
+#define IN_CLAMP(val)		clamp_val(val, 0, 255 * 19)
+#define IN_TO_REG(val)		DIV_ROUND_CLOSEST(IN_CLAMP(val), 19)
+
+static ssize_t get_in_input(struct device *dev, struct device_attribute *attr,
+			    char *buf)
+{
+	int n = to_sensor_dev_attr(attr)->index;
+	struct gl520_data *data = gl520_update_device(dev);
+	u8 r = data->in_input[n];
+
+	if (n == 0)
+		return sprintf(buf, "%d\n", VDD_FROM_REG(r));
+	else
+		return sprintf(buf, "%d\n", IN_FROM_REG(r));
+}
+
+static ssize_t get_in_min(struct device *dev, struct device_attribute *attr,
+			  char *buf)
+{
+	int n = to_sensor_dev_attr(attr)->index;
+	struct gl520_data *data = gl520_update_device(dev);
+	u8 r = data->in_min[n];
+
+	if (n == 0)
+		return sprintf(buf, "%d\n", VDD_FROM_REG(r));
+	else
+		return sprintf(buf, "%d\n", IN_FROM_REG(r));
+}
+
+static ssize_t get_in_max(struct device *dev, struct device_attribute *attr,
+			  char *buf)
+{
+	int n = to_sensor_dev_attr(attr)->index;
+	struct gl520_data *data = gl520_update_device(dev);
+	u8 r = data->in_max[n];
+
+	if (n == 0)
+		return sprintf(buf, "%d\n", VDD_FROM_REG(r));
+	else
+		return sprintf(buf, "%d\n", IN_FROM_REG(r));
+}
+
+static ssize_t set_in_min(struct device *dev, struct device_attribute *attr,
+			  const char *buf, size_t count)
+{
+	struct gl520_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
+	int n = to_sensor_dev_attr(attr)->index;
+	u8 r;
+	long v;
+	int err;
+
+	err = kstrtol(buf, 10, &v);
+	if (err)
+		return err;
+
+	mutex_lock(&data->update_lock);
+
+	if (n == 0)
+		r = VDD_TO_REG(v);
+	else
+		r = IN_TO_REG(v);
+
+	data->in_min[n] = r;
+
+	if (n < 4)
+		gl520_write_value(client, GL520_REG_IN_MIN[n],
+				  (gl520_read_value(client, GL520_REG_IN_MIN[n])
+				   & ~0xff) | r);
+	else
+		gl520_write_value(client, GL520_REG_IN_MIN[n], r);
+
+	mutex_unlock(&data->update_lock);
+	return count;
+}
+
+static ssize_t set_in_max(struct device *dev, struct device_attribute *attr,
+			  const char *buf, size_t count)
+{
+	struct gl520_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
+	int n = to_sensor_dev_attr(attr)->index;
+	u8 r;
+	long v;
+	int err;
+
+	err = kstrtol(buf, 10, &v);
+	if (err)
+		return err;
+
+	if (n == 0)
+		r = VDD_TO_REG(v);
+	else
+		r = IN_TO_REG(v);
+
+	mutex_lock(&data->update_lock);
+
+	data->in_max[n] = r;
+
+	if (n < 4)
+		gl520_write_value(client, GL520_REG_IN_MAX[n],
+				  (gl520_read_value(client, GL520_REG_IN_MAX[n])
+				   & ~0xff00) | (r << 8));
+	else
+		gl520_write_value(client, GL520_REG_IN_MAX[n], r);
+
+	mutex_unlock(&data->update_lock);
+	return count;
+}
+
+static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, get_in_input, NULL, 0);
+static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, get_in_input, NULL, 1);
+static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, get_in_input, NULL, 2);
+static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, get_in_input, NULL, 3);
+static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, get_in_input, NULL, 4);
+static SENSOR_DEVICE_ATTR(in0_min, S_IRUGO | S_IWUSR,
+		get_in_min, set_in_min, 0);
+static SENSOR_DEVICE_ATTR(in1_min, S_IRUGO | S_IWUSR,
+		get_in_min, set_in_min, 1);
+static SENSOR_DEVICE_ATTR(in2_min, S_IRUGO | S_IWUSR,
+		get_in_min, set_in_min, 2);
+static SENSOR_DEVICE_ATTR(in3_min, S_IRUGO | S_IWUSR,
+		get_in_min, set_in_min, 3);
+static SENSOR_DEVICE_ATTR(in4_min, S_IRUGO | S_IWUSR,
+		get_in_min, set_in_min, 4);
+static SENSOR_DEVICE_ATTR(in0_max, S_IRUGO | S_IWUSR,
+		get_in_max, set_in_max, 0);
+static SENSOR_DEVICE_ATTR(in1_max, S_IRUGO | S_IWUSR,
+		get_in_max, set_in_max, 1);
+static SENSOR_DEVICE_ATTR(in2_max, S_IRUGO | S_IWUSR,
+		get_in_max, set_in_max, 2);
+static SENSOR_DEVICE_ATTR(in3_max, S_IRUGO | S_IWUSR,
+		get_in_max, set_in_max, 3);
+static SENSOR_DEVICE_ATTR(in4_max, S_IRUGO | S_IWUSR,
+		get_in_max, set_in_max, 4);
+
+#define DIV_FROM_REG(val) (1 << (val))
+#define FAN_FROM_REG(val, div) ((val) == 0 ? 0 : (480000 / ((val) << (div))))
+
+#define FAN_BASE(div)		(480000 >> (div))
+#define FAN_CLAMP(val, div)	clamp_val(val, FAN_BASE(div) / 255, \
+					  FAN_BASE(div))
+#define FAN_TO_REG(val, div)	((val) == 0 ? 0 : \
+				 DIV_ROUND_CLOSEST(480000, \
+						FAN_CLAMP(val, div) << (div)))
+
+static ssize_t get_fan_input(struct device *dev, struct device_attribute *attr,
+			     char *buf)
+{
+	int n = to_sensor_dev_attr(attr)->index;
+	struct gl520_data *data = gl520_update_device(dev);
+
+	return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan_input[n],
+						 data->fan_div[n]));
+}
+
+static ssize_t get_fan_min(struct device *dev, struct device_attribute *attr,
+			   char *buf)
+{
+	int n = to_sensor_dev_attr(attr)->index;
+	struct gl520_data *data = gl520_update_device(dev);
+
+	return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan_min[n],
+						 data->fan_div[n]));
+}
+
+static ssize_t get_fan_div(struct device *dev, struct device_attribute *attr,
+			   char *buf)
+{
+	int n = to_sensor_dev_attr(attr)->index;
+	struct gl520_data *data = gl520_update_device(dev);
+
+	return sprintf(buf, "%d\n", DIV_FROM_REG(data->fan_div[n]));
+}
+
+static ssize_t fan1_off_show(struct device *dev,
+			     struct device_attribute *attr, char *buf)
+{
+	struct gl520_data *data = gl520_update_device(dev);
+	return sprintf(buf, "%d\n", data->fan_off);
+}
+
+static ssize_t set_fan_min(struct device *dev, struct device_attribute *attr,
+			   const char *buf, size_t count)
+{
+	struct gl520_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
+	int n = to_sensor_dev_attr(attr)->index;
+	u8 r;
+	unsigned long v;
+	int err;
+
+	err = kstrtoul(buf, 10, &v);
+	if (err)
+		return err;
+
+	mutex_lock(&data->update_lock);
+	r = FAN_TO_REG(v, data->fan_div[n]);
+	data->fan_min[n] = r;
+
+	if (n == 0)
+		gl520_write_value(client, GL520_REG_FAN_MIN,
+				  (gl520_read_value(client, GL520_REG_FAN_MIN)
+				   & ~0xff00) | (r << 8));
+	else
+		gl520_write_value(client, GL520_REG_FAN_MIN,
+				  (gl520_read_value(client, GL520_REG_FAN_MIN)
+				   & ~0xff) | r);
+
+	data->beep_mask = gl520_read_value(client, GL520_REG_BEEP_MASK);
+	if (data->fan_min[n] == 0)
+		data->alarm_mask &= (n == 0) ? ~0x20 : ~0x40;
+	else
+		data->alarm_mask |= (n == 0) ? 0x20 : 0x40;
+	data->beep_mask &= data->alarm_mask;
+	gl520_write_value(client, GL520_REG_BEEP_MASK, data->beep_mask);
+
+	mutex_unlock(&data->update_lock);
+	return count;
+}
+
+static ssize_t set_fan_div(struct device *dev, struct device_attribute *attr,
+			   const char *buf, size_t count)
+{
+	struct gl520_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
+	int n = to_sensor_dev_attr(attr)->index;
+	u8 r;
+	unsigned long v;
+	int err;
+
+	err = kstrtoul(buf, 10, &v);
+	if (err)
+		return err;
+
+	switch (v) {
+	case 1:
+		r = 0;
+		break;
+	case 2:
+		r = 1;
+		break;
+	case 4:
+		r = 2;
+		break;
+	case 8:
+		r = 3;
+		break;
+	default:
+		dev_err(&client->dev,
+	"fan_div value %ld not supported. Choose one of 1, 2, 4 or 8!\n", v);
+		return -EINVAL;
+	}
+
+	mutex_lock(&data->update_lock);
+	data->fan_div[n] = r;
+
+	if (n == 0)
+		gl520_write_value(client, GL520_REG_FAN_DIV,
+				  (gl520_read_value(client, GL520_REG_FAN_DIV)
+				   & ~0xc0) | (r << 6));
+	else
+		gl520_write_value(client, GL520_REG_FAN_DIV,
+				  (gl520_read_value(client, GL520_REG_FAN_DIV)
+				   & ~0x30) | (r << 4));
+
+	mutex_unlock(&data->update_lock);
+	return count;
+}
+
+static ssize_t fan1_off_store(struct device *dev,
+			      struct device_attribute *attr, const char *buf,
+			      size_t count)
+{
+	struct gl520_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
+	u8 r;
+	unsigned long v;
+	int err;
+
+	err = kstrtoul(buf, 10, &v);
+	if (err)
+		return err;
+
+	r = (v ? 1 : 0);
+
+	mutex_lock(&data->update_lock);
+	data->fan_off = r;
+	gl520_write_value(client, GL520_REG_FAN_OFF,
+			  (gl520_read_value(client, GL520_REG_FAN_OFF)
+			   & ~0x0c) | (r << 2));
+	mutex_unlock(&data->update_lock);
+	return count;
+}
+
+static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, get_fan_input, NULL, 0);
+static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, get_fan_input, NULL, 1);
+static SENSOR_DEVICE_ATTR(fan1_min, S_IRUGO | S_IWUSR,
+		get_fan_min, set_fan_min, 0);
+static SENSOR_DEVICE_ATTR(fan2_min, S_IRUGO | S_IWUSR,
+		get_fan_min, set_fan_min, 1);
+static SENSOR_DEVICE_ATTR(fan1_div, S_IRUGO | S_IWUSR,
+		get_fan_div, set_fan_div, 0);
+static SENSOR_DEVICE_ATTR(fan2_div, S_IRUGO | S_IWUSR,
+		get_fan_div, set_fan_div, 1);
+static DEVICE_ATTR_RW(fan1_off);
+
+#define TEMP_FROM_REG(val)	(((val) - 130) * 1000)
+#define TEMP_CLAMP(val)		clamp_val(val, -130000, 125000)
+#define TEMP_TO_REG(val)	(DIV_ROUND_CLOSEST(TEMP_CLAMP(val), 1000) + 130)
+
+static ssize_t get_temp_input(struct device *dev, struct device_attribute *attr,
+			      char *buf)
+{
+	int n = to_sensor_dev_attr(attr)->index;
+	struct gl520_data *data = gl520_update_device(dev);
+
+	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_input[n]));
+}
+
+static ssize_t get_temp_max(struct device *dev, struct device_attribute *attr,
+			    char *buf)
+{
+	int n = to_sensor_dev_attr(attr)->index;
+	struct gl520_data *data = gl520_update_device(dev);
+
+	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_max[n]));
+}
+
+static ssize_t get_temp_max_hyst(struct device *dev,
+				 struct device_attribute *attr, char *buf)
+{
+	int n = to_sensor_dev_attr(attr)->index;
+	struct gl520_data *data = gl520_update_device(dev);
+
+	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_max_hyst[n]));
+}
+
+static ssize_t set_temp_max(struct device *dev, struct device_attribute *attr,
+			    const char *buf, size_t count)
+{
+	struct gl520_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
+	int n = to_sensor_dev_attr(attr)->index;
+	long v;
+	int err;
+
+	err = kstrtol(buf, 10, &v);
+	if (err)
+		return err;
+
+	mutex_lock(&data->update_lock);
+	data->temp_max[n] = TEMP_TO_REG(v);
+	gl520_write_value(client, GL520_REG_TEMP_MAX[n], data->temp_max[n]);
+	mutex_unlock(&data->update_lock);
+	return count;
+}
+
+static ssize_t set_temp_max_hyst(struct device *dev, struct device_attribute
+				 *attr, const char *buf, size_t count)
+{
+	struct gl520_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
+	int n = to_sensor_dev_attr(attr)->index;
+	long v;
+	int err;
+
+	err = kstrtol(buf, 10, &v);
+	if (err)
+		return err;
+
+	mutex_lock(&data->update_lock);
+	data->temp_max_hyst[n] = TEMP_TO_REG(v);
+	gl520_write_value(client, GL520_REG_TEMP_MAX_HYST[n],
+			  data->temp_max_hyst[n]);
+	mutex_unlock(&data->update_lock);
+	return count;
+}
+
+static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, get_temp_input, NULL, 0);
+static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, get_temp_input, NULL, 1);
+static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO | S_IWUSR,
+		get_temp_max, set_temp_max, 0);
+static SENSOR_DEVICE_ATTR(temp2_max, S_IRUGO | S_IWUSR,
+		get_temp_max, set_temp_max, 1);
+static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IRUGO | S_IWUSR,
+		get_temp_max_hyst, set_temp_max_hyst, 0);
+static SENSOR_DEVICE_ATTR(temp2_max_hyst, S_IRUGO | S_IWUSR,
+		get_temp_max_hyst, set_temp_max_hyst, 1);
+
+static ssize_t alarms_show(struct device *dev, struct device_attribute *attr,
+			   char *buf)
+{
+	struct gl520_data *data = gl520_update_device(dev);
+	return sprintf(buf, "%d\n", data->alarms);
+}
+
+static ssize_t beep_enable_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct gl520_data *data = gl520_update_device(dev);
+	return sprintf(buf, "%d\n", data->beep_enable);
+}
+
+static ssize_t beep_mask_show(struct device *dev,
+			      struct device_attribute *attr, char *buf)
+{
+	struct gl520_data *data = gl520_update_device(dev);
+	return sprintf(buf, "%d\n", data->beep_mask);
+}
+
+static ssize_t beep_enable_store(struct device *dev,
+				 struct device_attribute *attr,
+				 const char *buf, size_t count)
+{
+	struct gl520_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
+	u8 r;
+	unsigned long v;
+	int err;
+
+	err = kstrtoul(buf, 10, &v);
+	if (err)
+		return err;
+
+	r = (v ? 0 : 1);
+
+	mutex_lock(&data->update_lock);
+	data->beep_enable = !r;
+	gl520_write_value(client, GL520_REG_BEEP_ENABLE,
+			  (gl520_read_value(client, GL520_REG_BEEP_ENABLE)
+			   & ~0x04) | (r << 2));
+	mutex_unlock(&data->update_lock);
+	return count;
+}
+
+static ssize_t beep_mask_store(struct device *dev,
+			       struct device_attribute *attr, const char *buf,
+			       size_t count)
+{
+	struct gl520_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
+	unsigned long r;
+	int err;
+
+	err = kstrtoul(buf, 10, &r);
+	if (err)
+		return err;
+
+	mutex_lock(&data->update_lock);
+	r &= data->alarm_mask;
+	data->beep_mask = r;
+	gl520_write_value(client, GL520_REG_BEEP_MASK, r);
+	mutex_unlock(&data->update_lock);
+	return count;
+}
+
+static DEVICE_ATTR_RO(alarms);
+static DEVICE_ATTR_RW(beep_enable);
+static DEVICE_ATTR_RW(beep_mask);
+
+static ssize_t get_alarm(struct device *dev, struct device_attribute *attr,
+			 char *buf)
+{
+	int bit_nr = to_sensor_dev_attr(attr)->index;
+	struct gl520_data *data = gl520_update_device(dev);
+
+	return sprintf(buf, "%d\n", (data->alarms >> bit_nr) & 1);
+}
+
+static SENSOR_DEVICE_ATTR(in0_alarm, S_IRUGO, get_alarm, NULL, 0);
+static SENSOR_DEVICE_ATTR(in1_alarm, S_IRUGO, get_alarm, NULL, 1);
+static SENSOR_DEVICE_ATTR(in2_alarm, S_IRUGO, get_alarm, NULL, 2);
+static SENSOR_DEVICE_ATTR(in3_alarm, S_IRUGO, get_alarm, NULL, 3);
+static SENSOR_DEVICE_ATTR(temp1_alarm, S_IRUGO, get_alarm, NULL, 4);
+static SENSOR_DEVICE_ATTR(fan1_alarm, S_IRUGO, get_alarm, NULL, 5);
+static SENSOR_DEVICE_ATTR(fan2_alarm, S_IRUGO, get_alarm, NULL, 6);
+static SENSOR_DEVICE_ATTR(temp2_alarm, S_IRUGO, get_alarm, NULL, 7);
+static SENSOR_DEVICE_ATTR(in4_alarm, S_IRUGO, get_alarm, NULL, 7);
+
+static ssize_t get_beep(struct device *dev, struct device_attribute *attr,
+			char *buf)
+{
+	int bitnr = to_sensor_dev_attr(attr)->index;
+	struct gl520_data *data = gl520_update_device(dev);
+
+	return sprintf(buf, "%d\n", (data->beep_mask >> bitnr) & 1);
+}
+
+static ssize_t set_beep(struct device *dev, struct device_attribute *attr,
+			const char *buf, size_t count)
+{
+	struct gl520_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
+	int bitnr = to_sensor_dev_attr(attr)->index;
+	unsigned long bit;
+
+	int err;
+
+	err = kstrtoul(buf, 10, &bit);
+	if (err)
+		return err;
+	if (bit & ~1)
+		return -EINVAL;
+
+	mutex_lock(&data->update_lock);
+	data->beep_mask = gl520_read_value(client, GL520_REG_BEEP_MASK);
+	if (bit)
+		data->beep_mask |= (1 << bitnr);
+	else
+		data->beep_mask &= ~(1 << bitnr);
+	gl520_write_value(client, GL520_REG_BEEP_MASK, data->beep_mask);
+	mutex_unlock(&data->update_lock);
+	return count;
+}
+
+static SENSOR_DEVICE_ATTR(in0_beep, S_IRUGO | S_IWUSR, get_beep, set_beep, 0);
+static SENSOR_DEVICE_ATTR(in1_beep, S_IRUGO | S_IWUSR, get_beep, set_beep, 1);
+static SENSOR_DEVICE_ATTR(in2_beep, S_IRUGO | S_IWUSR, get_beep, set_beep, 2);
+static SENSOR_DEVICE_ATTR(in3_beep, S_IRUGO | S_IWUSR, get_beep, set_beep, 3);
+static SENSOR_DEVICE_ATTR(temp1_beep, S_IRUGO | S_IWUSR, get_beep, set_beep, 4);
+static SENSOR_DEVICE_ATTR(fan1_beep, S_IRUGO | S_IWUSR, get_beep, set_beep, 5);
+static SENSOR_DEVICE_ATTR(fan2_beep, S_IRUGO | S_IWUSR, get_beep, set_beep, 6);
+static SENSOR_DEVICE_ATTR(temp2_beep, S_IRUGO | S_IWUSR, get_beep, set_beep, 7);
+static SENSOR_DEVICE_ATTR(in4_beep, S_IRUGO | S_IWUSR, get_beep, set_beep, 7);
+
+static struct attribute *gl520_attributes[] = {
+	&dev_attr_cpu0_vid.attr,
+
+	&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_in0_beep.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_in1_beep.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_in2_beep.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_in3_beep.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_fan1_beep.dev_attr.attr,
+	&dev_attr_fan1_off.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_fan2_beep.dev_attr.attr,
+
+	&sensor_dev_attr_temp1_input.dev_attr.attr,
+	&sensor_dev_attr_temp1_max.dev_attr.attr,
+	&sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
+	&sensor_dev_attr_temp1_alarm.dev_attr.attr,
+	&sensor_dev_attr_temp1_beep.dev_attr.attr,
+
+	&dev_attr_alarms.attr,
+	&dev_attr_beep_enable.attr,
+	&dev_attr_beep_mask.attr,
+	NULL
+};
+
+static const struct attribute_group gl520_group = {
+	.attrs = gl520_attributes,
+};
+
+static struct attribute *gl520_attributes_in4[] = {
+	&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_in4_beep.dev_attr.attr,
+	NULL
+};
+
+static struct attribute *gl520_attributes_temp2[] = {
+	&sensor_dev_attr_temp2_input.dev_attr.attr,
+	&sensor_dev_attr_temp2_max.dev_attr.attr,
+	&sensor_dev_attr_temp2_max_hyst.dev_attr.attr,
+	&sensor_dev_attr_temp2_alarm.dev_attr.attr,
+	&sensor_dev_attr_temp2_beep.dev_attr.attr,
+	NULL
+};
+
+static const struct attribute_group gl520_group_in4 = {
+	.attrs = gl520_attributes_in4,
+};
+
+static const struct attribute_group gl520_group_temp2 = {
+	.attrs = gl520_attributes_temp2,
+};
+
+
+/*
+ * Real code
+ */
+
+/* Return 0 if detection is successful, -ENODEV otherwise */
+static int gl520_detect(struct i2c_client *client, struct i2c_board_info *info)
+{
+	struct i2c_adapter *adapter = client->adapter;
+
+	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
+				     I2C_FUNC_SMBUS_WORD_DATA))
+		return -ENODEV;
+
+	/* Determine the chip type. */
+	if ((gl520_read_value(client, GL520_REG_CHIP_ID) != 0x20) ||
+	    ((gl520_read_value(client, GL520_REG_REVISION) & 0x7f) != 0x00) ||
+	    ((gl520_read_value(client, GL520_REG_CONF) & 0x80) != 0x00)) {
+		dev_dbg(&client->dev, "Unknown chip type, skipping\n");
+		return -ENODEV;
+	}
+
+	strlcpy(info->type, "gl520sm", I2C_NAME_SIZE);
+
+	return 0;
+}
+
+/* Called when we have found a new GL520SM. */
+static void gl520_init_client(struct i2c_client *client)
+{
+	struct gl520_data *data = i2c_get_clientdata(client);
+	u8 oldconf, conf;
+
+	conf = oldconf = gl520_read_value(client, GL520_REG_CONF);
+
+	data->alarm_mask = 0xff;
+	data->vrm = vid_which_vrm();
+
+	if (extra_sensor_type == 1)
+		conf &= ~0x10;
+	else if (extra_sensor_type == 2)
+		conf |= 0x10;
+	data->two_temps = !(conf & 0x10);
+
+	/* If IRQ# is disabled, we can safely force comparator mode */
+	if (!(conf & 0x20))
+		conf &= 0xf7;
+
+	/* Enable monitoring if needed */
+	conf |= 0x40;
+
+	if (conf != oldconf)
+		gl520_write_value(client, GL520_REG_CONF, conf);
+
+	gl520_update_device(&(client->dev));
+
+	if (data->fan_min[0] == 0)
+		data->alarm_mask &= ~0x20;
+	if (data->fan_min[1] == 0)
+		data->alarm_mask &= ~0x40;
+
+	data->beep_mask &= data->alarm_mask;
+	gl520_write_value(client, GL520_REG_BEEP_MASK, data->beep_mask);
+}
+
+static int gl520_probe(struct i2c_client *client,
+		       const struct i2c_device_id *id)
+{
+	struct device *dev = &client->dev;
+	struct device *hwmon_dev;
+	struct gl520_data *data;
+
+	data = devm_kzalloc(dev, sizeof(struct gl520_data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	i2c_set_clientdata(client, data);
+	mutex_init(&data->update_lock);
+	data->client = client;
+
+	/* Initialize the GL520SM chip */
+	gl520_init_client(client);
+
+	/* sysfs hooks */
+	data->groups[0] = &gl520_group;
+
+	if (data->two_temps)
+		data->groups[1] = &gl520_group_temp2;
+	else
+		data->groups[1] = &gl520_group_in4;
+
+	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
+							   data, data->groups);
+	return PTR_ERR_OR_ZERO(hwmon_dev);
+}
+
+static const struct i2c_device_id gl520_id[] = {
+	{ "gl520sm", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, gl520_id);
+
+static struct i2c_driver gl520_driver = {
+	.class		= I2C_CLASS_HWMON,
+	.driver = {
+		.name	= "gl520sm",
+	},
+	.probe		= gl520_probe,
+	.id_table	= gl520_id,
+	.detect		= gl520_detect,
+	.address_list	= normal_i2c,
+};
+
+module_i2c_driver(gl520_driver);
+
+MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>, "
+	"Kyösti Mälkki <kmalkki@cc.hut.fi>, "
+	"Maarten Deprez <maartendeprez@users.sourceforge.net>");
+MODULE_DESCRIPTION("GL520SM driver");
+MODULE_LICENSE("GPL");