[deliverable/linux.git] / drivers / hwmon / lm92.c

/*
 * lm92 - Hardware monitoring driver
 * Copyright (C) 2005  Jean Delvare <khali@linux-fr.org>
 *
 * Based on the lm90 driver, with some ideas taken from the lm_sensors
 * lm92 driver as well.
 *
 * The LM92 is a sensor chip made by National Semiconductor. It reports
 * its own temperature with a 0.0625 deg resolution and a 0.33 deg
 * accuracy. Complete datasheet can be obtained from National's website
 * at:
 *   http://www.national.com/pf/LM/LM92.html
 *
 * This driver also supports the MAX6635 sensor chip made by Maxim.
 * This chip is compatible with the LM92, but has a lesser accuracy
 * (1.0 deg). Complete datasheet can be obtained from Maxim's website
 * at:
 *   http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3074
 *
 * Since the LM92 was the first chipset supported by this driver, most
 * comments will refer to this chipset, but are actually general and
 * concern all supported chipsets, unless mentioned otherwise.
 *
 * Support could easily be added for the National Semiconductor LM76
 * and Maxim MAX6633 and MAX6634 chips, which are mostly compatible
 * with the LM92.
 *
 * 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/i2c.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/err.h>
#include <linux/mutex.h>

/* The LM92 and MAX6635 have 2 two-state pins for address selection,
   resulting in 4 possible addresses. */
static unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b,
				       I2C_CLIENT_END };

/* Insmod parameters */
I2C_CLIENT_INSMOD_1(lm92);

/* The LM92 registers */
#define LM92_REG_CONFIG			0x01 /* 8-bit, RW */
#define LM92_REG_TEMP			0x00 /* 16-bit, RO */
#define LM92_REG_TEMP_HYST		0x02 /* 16-bit, RW */
#define LM92_REG_TEMP_CRIT		0x03 /* 16-bit, RW */
#define LM92_REG_TEMP_LOW		0x04 /* 16-bit, RW */
#define LM92_REG_TEMP_HIGH		0x05 /* 16-bit, RW */
#define LM92_REG_MAN_ID			0x07 /* 16-bit, RO, LM92 only */

/* The LM92 uses signed 13-bit values with LSB = 0.0625 degree Celsius,
   left-justified in 16-bit registers. No rounding is done, with such
   a resolution it's just not worth it. Note that the MAX6635 doesn't
   make use of the 4 lower bits for limits (i.e. effective resolution
   for limits is 1 degree Celsius). */
static inline int TEMP_FROM_REG(s16 reg)
{
	return reg / 8 * 625 / 10;
}

static inline s16 TEMP_TO_REG(int val)
{
	if (val <= -60000)
		return -60000 * 10 / 625 * 8;
	if (val >= 160000)
		return 160000 * 10 / 625 * 8;
	return val * 10 / 625 * 8;
}

/* Alarm flags are stored in the 3 LSB of the temperature register */
static inline u8 ALARMS_FROM_REG(s16 reg)
{
	return reg & 0x0007;
}

/* Driver data (common to all clients) */
static struct i2c_driver lm92_driver;

/* Client data (each client gets its own) */
struct lm92_data {
	struct i2c_client client;
	struct device *hwmon_dev;
	struct mutex update_lock;
	char valid; /* zero until following fields are valid */
	unsigned long last_updated; /* in jiffies */

	/* registers values */
	s16 temp1_input, temp1_crit, temp1_min, temp1_max, temp1_hyst;
};


/*
 * Sysfs attributes and callback functions
 */

static struct lm92_data *lm92_update_device(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct lm92_data *data = i2c_get_clientdata(client);

	mutex_lock(&data->update_lock);

	if (time_after(jiffies, data->last_updated + HZ)
	 || !data->valid) {
		dev_dbg(&client->dev, "Updating lm92 data\n");
		data->temp1_input = swab16(i2c_smbus_read_word_data(client,
				    LM92_REG_TEMP));
		data->temp1_hyst = swab16(i2c_smbus_read_word_data(client,
				    LM92_REG_TEMP_HYST));
		data->temp1_crit = swab16(i2c_smbus_read_word_data(client,
				    LM92_REG_TEMP_CRIT));
		data->temp1_min = swab16(i2c_smbus_read_word_data(client,
				    LM92_REG_TEMP_LOW));
		data->temp1_max = swab16(i2c_smbus_read_word_data(client,
				    LM92_REG_TEMP_HIGH));

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

	mutex_unlock(&data->update_lock);

	return data;
}

#define show_temp(value) \
static ssize_t show_##value(struct device *dev, struct device_attribute *attr, char *buf) \
{ \
	struct lm92_data *data = lm92_update_device(dev); \
	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->value)); \
}
show_temp(temp1_input);
show_temp(temp1_crit);
show_temp(temp1_min);
show_temp(temp1_max);

#define set_temp(value, reg) \
static ssize_t set_##value(struct device *dev, struct device_attribute *attr, const char *buf, \
	size_t count) \
{ \
	struct i2c_client *client = to_i2c_client(dev); \
	struct lm92_data *data = i2c_get_clientdata(client); \
	long val = simple_strtol(buf, NULL, 10); \
 \
	mutex_lock(&data->update_lock); \
	data->value = TEMP_TO_REG(val); \
	i2c_smbus_write_word_data(client, reg, swab16(data->value)); \
	mutex_unlock(&data->update_lock); \
	return count; \
}
set_temp(temp1_crit, LM92_REG_TEMP_CRIT);
set_temp(temp1_min, LM92_REG_TEMP_LOW);
set_temp(temp1_max, LM92_REG_TEMP_HIGH);

static ssize_t show_temp1_crit_hyst(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct lm92_data *data = lm92_update_device(dev);
	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp1_crit)
		       - TEMP_FROM_REG(data->temp1_hyst));
}
static ssize_t show_temp1_max_hyst(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct lm92_data *data = lm92_update_device(dev);
	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp1_max)
		       - TEMP_FROM_REG(data->temp1_hyst));
}
static ssize_t show_temp1_min_hyst(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct lm92_data *data = lm92_update_device(dev);
	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp1_min)
		       + TEMP_FROM_REG(data->temp1_hyst));
}

static ssize_t set_temp1_crit_hyst(struct device *dev, struct device_attribute *attr, const char *buf,
	size_t count)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct lm92_data *data = i2c_get_clientdata(client);
	long val = simple_strtol(buf, NULL, 10);

	mutex_lock(&data->update_lock);
	data->temp1_hyst = TEMP_FROM_REG(data->temp1_crit) - val;
	i2c_smbus_write_word_data(client, LM92_REG_TEMP_HYST,
				  swab16(TEMP_TO_REG(data->temp1_hyst)));
	mutex_unlock(&data->update_lock);
	return count;
}

static ssize_t show_alarms(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct lm92_data *data = lm92_update_device(dev);
	return sprintf(buf, "%d\n", ALARMS_FROM_REG(data->temp1_input));
}

static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
			  char *buf)
{
	int bitnr = to_sensor_dev_attr(attr)->index;
	struct lm92_data *data = lm92_update_device(dev);
	return sprintf(buf, "%d\n", (data->temp1_input >> bitnr) & 1);
}

static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp1_input, NULL);
static DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO, show_temp1_crit,
	set_temp1_crit);
static DEVICE_ATTR(temp1_crit_hyst, S_IWUSR | S_IRUGO, show_temp1_crit_hyst,
	set_temp1_crit_hyst);
static DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, show_temp1_min,
	set_temp1_min);
static DEVICE_ATTR(temp1_min_hyst, S_IRUGO, show_temp1_min_hyst, NULL);
static DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp1_max,
	set_temp1_max);
static DEVICE_ATTR(temp1_max_hyst, S_IRUGO, show_temp1_max_hyst, NULL);
static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL, 2);
static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL, 0);
static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 1);


/*
 * Detection and registration
 */

static void lm92_init_client(struct i2c_client *client)
{
	u8 config;

	/* Start the conversions if needed */
	config = i2c_smbus_read_byte_data(client, LM92_REG_CONFIG);
	if (config & 0x01)
		i2c_smbus_write_byte_data(client, LM92_REG_CONFIG,
					  config & 0xFE);
}

/* The MAX6635 has no identification register, so we have to use tricks
   to identify it reliably. This is somewhat slow.
   Note that we do NOT rely on the 2 MSB of the configuration register
   always reading 0, as suggested by the datasheet, because it was once
   reported not to be true. */
static int max6635_check(struct i2c_client *client)
{
	u16 temp_low, temp_high, temp_hyst, temp_crit;
	u8 conf;
	int i;

	/* No manufacturer ID register, so a read from this address will
	   always return the last read value. */
	temp_low = i2c_smbus_read_word_data(client, LM92_REG_TEMP_LOW);
	if (i2c_smbus_read_word_data(client, LM92_REG_MAN_ID) != temp_low)
		return 0;
	temp_high = i2c_smbus_read_word_data(client, LM92_REG_TEMP_HIGH);
	if (i2c_smbus_read_word_data(client, LM92_REG_MAN_ID) != temp_high)
		return 0;
	
	/* Limits are stored as integer values (signed, 9-bit). */
	if ((temp_low & 0x7f00) || (temp_high & 0x7f00))
		return 0;
	temp_hyst = i2c_smbus_read_word_data(client, LM92_REG_TEMP_HYST);
	temp_crit = i2c_smbus_read_word_data(client, LM92_REG_TEMP_CRIT);
	if ((temp_hyst & 0x7f00) || (temp_crit & 0x7f00))
		return 0;

	/* Registers addresses were found to cycle over 16-byte boundaries.
	   We don't test all registers with all offsets so as to save some
	   reads and time, but this should still be sufficient to dismiss
	   non-MAX6635 chips. */
	conf = i2c_smbus_read_byte_data(client, LM92_REG_CONFIG);
	for (i=16; i<96; i*=2) {
		if (temp_hyst != i2c_smbus_read_word_data(client,
		 		 LM92_REG_TEMP_HYST + i - 16)
		 || temp_crit != i2c_smbus_read_word_data(client,
		 		 LM92_REG_TEMP_CRIT + i)
		 || temp_low != i2c_smbus_read_word_data(client,
				LM92_REG_TEMP_LOW + i + 16)
		 || temp_high != i2c_smbus_read_word_data(client,
		 		 LM92_REG_TEMP_HIGH + i + 32)
		 || conf != i2c_smbus_read_byte_data(client,
		 	    LM92_REG_CONFIG + i))
			return 0;
	}

	return 1;
}

static struct attribute *lm92_attributes[] = {
	&dev_attr_temp1_input.attr,
	&dev_attr_temp1_crit.attr,
	&dev_attr_temp1_crit_hyst.attr,
	&dev_attr_temp1_min.attr,
	&dev_attr_temp1_min_hyst.attr,
	&dev_attr_temp1_max.attr,
	&dev_attr_temp1_max_hyst.attr,
	&dev_attr_alarms.attr,
	&sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
	&sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
	NULL
};

static const struct attribute_group lm92_group = {
	.attrs = lm92_attributes,
};

/* The following function does more than just detection. If detection
   succeeds, it also registers the new chip. */
static int lm92_detect(struct i2c_adapter *adapter, int address, int kind)
{
	struct i2c_client *new_client;
	struct lm92_data *data;
	int err = 0;
	char *name;

	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA
					    | I2C_FUNC_SMBUS_WORD_DATA))
		goto exit;

	if (!(data = kzalloc(sizeof(struct lm92_data), GFP_KERNEL))) {
		err = -ENOMEM;
		goto exit;
	}

	/* Fill in enough client fields so that we can read from the chip,
	   which is required for identication */
	new_client = &data->client;
	i2c_set_clientdata(new_client, data);
	new_client->addr = address;
	new_client->adapter = adapter;
	new_client->driver = &lm92_driver;
	new_client->flags = 0;

	/* A negative kind means that the driver was loaded with no force
	   parameter (default), so we must identify the chip. */
	if (kind < 0) {
		u8 config = i2c_smbus_read_byte_data(new_client,
			     LM92_REG_CONFIG);
		u16 man_id = i2c_smbus_read_word_data(new_client,
			     LM92_REG_MAN_ID);

		if ((config & 0xe0) == 0x00
		 && man_id == 0x0180) {
			pr_info("lm92: Found National Semiconductor LM92 chip\n");
	 		kind = lm92;
		} else
		if (max6635_check(new_client)) {
			pr_info("lm92: Found Maxim MAX6635 chip\n");
			kind = lm92; /* No separate prefix */
		}
		else
			goto exit_free;
	} else
	if (kind == 0) /* Default to an LM92 if forced */
		kind = lm92;

	/* Give it the proper name */
	if (kind == lm92) {
		name = "lm92";
	} else { /* Supposedly cannot happen */
		dev_dbg(&new_client->dev, "Kind out of range?\n");
		goto exit_free;
	}

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

	/* Tell the i2c subsystem a new client has arrived */
	if ((err = i2c_attach_client(new_client)))
		goto exit_free;

	/* Initialize the chipset */
	lm92_init_client(new_client);

	/* Register sysfs hooks */
	if ((err = sysfs_create_group(&new_client->dev.kobj, &lm92_group)))
		goto exit_detach;

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

	return 0;

exit_remove:
	sysfs_remove_group(&new_client->dev.kobj, &lm92_group);
exit_detach:
	i2c_detach_client(new_client);
exit_free:
	kfree(data);
exit:
	return err;
}

static int lm92_attach_adapter(struct i2c_adapter *adapter)
{
	if (!(adapter->class & I2C_CLASS_HWMON))
		return 0;
	return i2c_probe(adapter, &addr_data, lm92_detect);
}

static int lm92_detach_client(struct i2c_client *client)
{
	struct lm92_data *data = i2c_get_clientdata(client);
	int err;

	hwmon_device_unregister(data->hwmon_dev);
	sysfs_remove_group(&client->dev.kobj, &lm92_group);

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

	kfree(data);
	return 0;
}


/*
 * Module and driver stuff
 */

static struct i2c_driver lm92_driver = {
	.driver = {
		.name	= "lm92",
	},
	.attach_adapter	= lm92_attach_adapter,
	.detach_client	= lm92_detach_client,
};

static int __init sensors_lm92_init(void)
{
	return i2c_add_driver(&lm92_driver);
}

static void __exit sensors_lm92_exit(void)
{
	i2c_del_driver(&lm92_driver);
}

MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>");
MODULE_DESCRIPTION("LM92/MAX6635 driver");
MODULE_LICENSE("GPL");

module_init(sensors_lm92_init);
module_exit(sensors_lm92_exit);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* lm92 - Hardware monitoring driver
	3	* Copyright (C) 2005 Jean Delvare <khali@linux-fr.org>
	4	*
	5	* Based on the lm90 driver, with some ideas taken from the lm_sensors
	6	* lm92 driver as well.
	7	*
	8	* The LM92 is a sensor chip made by National Semiconductor. It reports
	9	* its own temperature with a 0.0625 deg resolution and a 0.33 deg
	10	* accuracy. Complete datasheet can be obtained from National's website
	11	* at:
	12	* http://www.national.com/pf/LM/LM92.html
	13	*
	14	* This driver also supports the MAX6635 sensor chip made by Maxim.
	15	* This chip is compatible with the LM92, but has a lesser accuracy
	16	* (1.0 deg). Complete datasheet can be obtained from Maxim's website
	17	* at:
	18	* http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3074
	19	*
	20	* Since the LM92 was the first chipset supported by this driver, most
	21	* comments will refer to this chipset, but are actually general and
	22	* concern all supported chipsets, unless mentioned otherwise.
	23	*
	24	* Support could easily be added for the National Semiconductor LM76
	25	* and Maxim MAX6633 and MAX6634 chips, which are mostly compatible
	26	* with the LM92.
	27	*
	28	* This program is free software; you can redistribute it and/or modify
	29	* it under the terms of the GNU General Public License as published by
	30	* the Free Software Foundation; either version 2 of the License, or
	31	* (at your option) any later version.
	32	*
	33	* This program is distributed in the hope that it will be useful,
	34	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	35	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	36	* GNU General Public License for more details.
	37	*
	38	* You should have received a copy of the GNU General Public License
	39	* along with this program; if not, write to the Free Software
	40	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	41	*/
	42
	43	#include <linux/module.h>
	44	#include <linux/init.h>
	45	#include <linux/slab.h>
	46	#include <linux/i2c.h>
943b0830	47	#include <linux/hwmon.h>
6cb59e91	48	#include <linux/hwmon-sysfs.h>
943b0830	49	#include <linux/err.h>
9a61bf63	50	#include <linux/mutex.h>
1da177e4 LT	51
	52	/* The LM92 and MAX6635 have 2 two-state pins for address selection,
	53	resulting in 4 possible addresses. */
	54	static unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b,
	55	I2C_CLIENT_END };
1da177e4 LT	56
1da177e4 LT	57	/* Insmod parameters */
f4b50261	58	I2C_CLIENT_INSMOD_1(lm92);
1da177e4 LT	59
	60	/* The LM92 registers */
	61	#define LM92_REG_CONFIG 0x01 /* 8-bit, RW */
	62	#define LM92_REG_TEMP 0x00 /* 16-bit, RO */
	63	#define LM92_REG_TEMP_HYST 0x02 /* 16-bit, RW */
	64	#define LM92_REG_TEMP_CRIT 0x03 /* 16-bit, RW */
	65	#define LM92_REG_TEMP_LOW 0x04 /* 16-bit, RW */
	66	#define LM92_REG_TEMP_HIGH 0x05 /* 16-bit, RW */
	67	#define LM92_REG_MAN_ID 0x07 /* 16-bit, RO, LM92 only */
	68
	69	/* The LM92 uses signed 13-bit values with LSB = 0.0625 degree Celsius,
	70	left-justified in 16-bit registers. No rounding is done, with such
	71	a resolution it's just not worth it. Note that the MAX6635 doesn't
	72	make use of the 4 lower bits for limits (i.e. effective resolution
	73	for limits is 1 degree Celsius). */
	74	static inline int TEMP_FROM_REG(s16 reg)
	75	{
	76	return reg / 8 * 625 / 10;
	77	}
	78
	79	static inline s16 TEMP_TO_REG(int val)
	80	{
	81	if (val <= -60000)
	82	return -60000 * 10 / 625 * 8;
	83	if (val >= 160000)
	84	return 160000 * 10 / 625 * 8;
	85	return val * 10 / 625 * 8;
	86	}
	87
	88	/* Alarm flags are stored in the 3 LSB of the temperature register */
	89	static inline u8 ALARMS_FROM_REG(s16 reg)
	90	{
	91	return reg & 0x0007;
	92	}
	93
	94	/* Driver data (common to all clients) */
	95	static struct i2c_driver lm92_driver;
	96
	97	/* Client data (each client gets its own) */
	98	struct lm92_data {
	99	struct i2c_client client;
1beeffe4	100	struct device *hwmon_dev;
9a61bf63	101	struct mutex update_lock;
1da177e4 LT	102	char valid; /* zero until following fields are valid */
	103	unsigned long last_updated; /* in jiffies */
	104
	105	/* registers values */
	106	s16 temp1_input, temp1_crit, temp1_min, temp1_max, temp1_hyst;
	107	};
	108
	109
	110	/*
	111	* Sysfs attributes and callback functions
	112	*/
	113
	114	static struct lm92_data lm92_update_device(struct device dev)
	115	{
	116	struct i2c_client *client = to_i2c_client(dev);
	117	struct lm92_data *data = i2c_get_clientdata(client);
	118
9a61bf63	119	mutex_lock(&data->update_lock);
1da177e4 LT	120
	121	if (time_after(jiffies, data->last_updated + HZ)
	122	\|\| !data->valid) {
	123	dev_dbg(&client->dev, "Updating lm92 data\n");
	124	data->temp1_input = swab16(i2c_smbus_read_word_data(client,
	125	LM92_REG_TEMP));
	126	data->temp1_hyst = swab16(i2c_smbus_read_word_data(client,
	127	LM92_REG_TEMP_HYST));
	128	data->temp1_crit = swab16(i2c_smbus_read_word_data(client,
	129	LM92_REG_TEMP_CRIT));
	130	data->temp1_min = swab16(i2c_smbus_read_word_data(client,
	131	LM92_REG_TEMP_LOW));
	132	data->temp1_max = swab16(i2c_smbus_read_word_data(client,
	133	LM92_REG_TEMP_HIGH));
	134
	135	data->last_updated = jiffies;
	136	data->valid = 1;
	137	}
	138
9a61bf63	139	mutex_unlock(&data->update_lock);
1da177e4 LT	140
	141	return data;
	142	}
	143
	144	#define show_temp(value) \
8627f9ba	145	static ssize_t show_##value(struct device dev, struct device_attribute attr, char *buf) \
1da177e4 LT	146	{ \
	147	struct lm92_data *data = lm92_update_device(dev); \
	148	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->value)); \
	149	}
	150	show_temp(temp1_input);
	151	show_temp(temp1_crit);
	152	show_temp(temp1_min);
	153	show_temp(temp1_max);
	154
	155	#define set_temp(value, reg) \
8627f9ba	156	static ssize_t set_##value(struct device dev, struct device_attribute attr, const char *buf, \
1da177e4 LT	157	size_t count) \
	158	{ \
	159	struct i2c_client *client = to_i2c_client(dev); \
	160	struct lm92_data *data = i2c_get_clientdata(client); \
	161	long val = simple_strtol(buf, NULL, 10); \
	162	\
9a61bf63	163	mutex_lock(&data->update_lock); \
1da177e4 LT	164	data->value = TEMP_TO_REG(val); \
1da177e4 LT	165	i2c_smbus_write_word_data(client, reg, swab16(data->value)); \
9a61bf63	166	mutex_unlock(&data->update_lock); \
1da177e4 LT	167	return count; \
	168	}
	169	set_temp(temp1_crit, LM92_REG_TEMP_CRIT);
	170	set_temp(temp1_min, LM92_REG_TEMP_LOW);
	171	set_temp(temp1_max, LM92_REG_TEMP_HIGH);
	172
8627f9ba	173	static ssize_t show_temp1_crit_hyst(struct device dev, struct device_attribute attr, char *buf)
1da177e4 LT	174	{
	175	struct lm92_data *data = lm92_update_device(dev);
	176	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp1_crit)
	177	- TEMP_FROM_REG(data->temp1_hyst));
	178	}
8627f9ba	179	static ssize_t show_temp1_max_hyst(struct device dev, struct device_attribute attr, char *buf)
1da177e4 LT	180	{
	181	struct lm92_data *data = lm92_update_device(dev);
	182	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp1_max)
	183	- TEMP_FROM_REG(data->temp1_hyst));
	184	}
8627f9ba	185	static ssize_t show_temp1_min_hyst(struct device dev, struct device_attribute attr, char *buf)
1da177e4 LT	186	{
	187	struct lm92_data *data = lm92_update_device(dev);
	188	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp1_min)
	189	+ TEMP_FROM_REG(data->temp1_hyst));
	190	}
	191
8627f9ba	192	static ssize_t set_temp1_crit_hyst(struct device dev, struct device_attribute attr, const char *buf,
1da177e4 LT	193	size_t count)
	194	{
	195	struct i2c_client *client = to_i2c_client(dev);
	196	struct lm92_data *data = i2c_get_clientdata(client);
	197	long val = simple_strtol(buf, NULL, 10);
	198
9a61bf63	199	mutex_lock(&data->update_lock);
1da177e4 LT	200	data->temp1_hyst = TEMP_FROM_REG(data->temp1_crit) - val;
	201	i2c_smbus_write_word_data(client, LM92_REG_TEMP_HYST,
	202	swab16(TEMP_TO_REG(data->temp1_hyst)));
9a61bf63	203	mutex_unlock(&data->update_lock);
1da177e4 LT	204	return count;
	205	}
	206
8627f9ba	207	static ssize_t show_alarms(struct device dev, struct device_attribute attr, char *buf)
1da177e4 LT	208	{
	209	struct lm92_data *data = lm92_update_device(dev);
	210	return sprintf(buf, "%d\n", ALARMS_FROM_REG(data->temp1_input));
	211	}
	212
6cb59e91 JD	213	static ssize_t show_alarm(struct device dev, struct device_attribute attr,
	214	char *buf)
	215	{
	216	int bitnr = to_sensor_dev_attr(attr)->index;
	217	struct lm92_data *data = lm92_update_device(dev);
	218	return sprintf(buf, "%d\n", (data->temp1_input >> bitnr) & 1);
	219	}
	220
1da177e4 LT	221	static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp1_input, NULL);
	222	static DEVICE_ATTR(temp1_crit, S_IWUSR \| S_IRUGO, show_temp1_crit,
	223	set_temp1_crit);
	224	static DEVICE_ATTR(temp1_crit_hyst, S_IWUSR \| S_IRUGO, show_temp1_crit_hyst,
	225	set_temp1_crit_hyst);
	226	static DEVICE_ATTR(temp1_min, S_IWUSR \| S_IRUGO, show_temp1_min,
	227	set_temp1_min);
	228	static DEVICE_ATTR(temp1_min_hyst, S_IRUGO, show_temp1_min_hyst, NULL);
	229	static DEVICE_ATTR(temp1_max, S_IWUSR \| S_IRUGO, show_temp1_max,
	230	set_temp1_max);
	231	static DEVICE_ATTR(temp1_max_hyst, S_IRUGO, show_temp1_max_hyst, NULL);
	232	static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
6cb59e91 JD	233	static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL, 2);
	234	static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL, 0);
	235	static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 1);
1da177e4 LT	236
	237
	238	/*
	239	* Detection and registration
	240	*/
	241
	242	static void lm92_init_client(struct i2c_client *client)
	243	{
	244	u8 config;
	245
	246	/* Start the conversions if needed */
	247	config = i2c_smbus_read_byte_data(client, LM92_REG_CONFIG);
	248	if (config & 0x01)
	249	i2c_smbus_write_byte_data(client, LM92_REG_CONFIG,
	250	config & 0xFE);
	251	}
	252
	253	/* The MAX6635 has no identification register, so we have to use tricks
	254	to identify it reliably. This is somewhat slow.
	255	Note that we do NOT rely on the 2 MSB of the configuration register
	256	always reading 0, as suggested by the datasheet, because it was once
	257	reported not to be true. */
	258	static int max6635_check(struct i2c_client *client)
	259	{
	260	u16 temp_low, temp_high, temp_hyst, temp_crit;
	261	u8 conf;
	262	int i;
	263
	264	/* No manufacturer ID register, so a read from this address will
	265	always return the last read value. */
	266	temp_low = i2c_smbus_read_word_data(client, LM92_REG_TEMP_LOW);
	267	if (i2c_smbus_read_word_data(client, LM92_REG_MAN_ID) != temp_low)
	268	return 0;
	269	temp_high = i2c_smbus_read_word_data(client, LM92_REG_TEMP_HIGH);
	270	if (i2c_smbus_read_word_data(client, LM92_REG_MAN_ID) != temp_high)
	271	return 0;
	272
	273	/* Limits are stored as integer values (signed, 9-bit). */
	274	if ((temp_low & 0x7f00) \|\| (temp_high & 0x7f00))
	275	return 0;
	276	temp_hyst = i2c_smbus_read_word_data(client, LM92_REG_TEMP_HYST);
	277	temp_crit = i2c_smbus_read_word_data(client, LM92_REG_TEMP_CRIT);
	278	if ((temp_hyst & 0x7f00) \|\| (temp_crit & 0x7f00))
	279	return 0;
	280
	281	/* Registers addresses were found to cycle over 16-byte boundaries.
	282	We don't test all registers with all offsets so as to save some
	283	reads and time, but this should still be sufficient to dismiss
	284	non-MAX6635 chips. */
	285	conf = i2c_smbus_read_byte_data(client, LM92_REG_CONFIG);
	286	for (i=16; i<96; i*=2) {
	287	if (temp_hyst != i2c_smbus_read_word_data(client,
	288	LM92_REG_TEMP_HYST + i - 16)
	289	\|\| temp_crit != i2c_smbus_read_word_data(client,
	290	LM92_REG_TEMP_CRIT + i)
	291	\|\| temp_low != i2c_smbus_read_word_data(client,
	292	LM92_REG_TEMP_LOW + i + 16)
	293	\|\| temp_high != i2c_smbus_read_word_data(client,
	294	LM92_REG_TEMP_HIGH + i + 32)
	295	\|\| conf != i2c_smbus_read_byte_data(client,
	296	LM92_REG_CONFIG + i))
	297	return 0;
	298	}
	299
300	return 1;
301	}
302
0501a381 MH	303	static struct attribute *lm92_attributes[] = {
	304	&dev_attr_temp1_input.attr,
	305	&dev_attr_temp1_crit.attr,
	306	&dev_attr_temp1_crit_hyst.attr,
	307	&dev_attr_temp1_min.attr,
	308	&dev_attr_temp1_min_hyst.attr,
	309	&dev_attr_temp1_max.attr,
	310	&dev_attr_temp1_max_hyst.attr,
	311	&dev_attr_alarms.attr,
6cb59e91 JD	312	&sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
	313	&sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
	314	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
0501a381 MH	315	NULL
	316	};
	317
	318	static const struct attribute_group lm92_group = {
	319	.attrs = lm92_attributes,
	320	};
	321
1da177e4 LT	322	/* The following function does more than just detection. If detection
	323	succeeds, it also registers the new chip. */
	324	static int lm92_detect(struct i2c_adapter *adapter, int address, int kind)
	325	{
	326	struct i2c_client *new_client;
	327	struct lm92_data *data;
	328	int err = 0;
	329	char *name;
	330
	331	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA
	332	\| I2C_FUNC_SMBUS_WORD_DATA))
	333	goto exit;
	334
ba9c2e8d	335	if (!(data = kzalloc(sizeof(struct lm92_data), GFP_KERNEL))) {
1da177e4 LT	336	err = -ENOMEM;
	337	goto exit;
	338	}
1da177e4 LT	339
	340	/* Fill in enough client fields so that we can read from the chip,
	341	which is required for identication */
	342	new_client = &data->client;
	343	i2c_set_clientdata(new_client, data);
	344	new_client->addr = address;
	345	new_client->adapter = adapter;
	346	new_client->driver = &lm92_driver;
	347	new_client->flags = 0;
	348
	349	/* A negative kind means that the driver was loaded with no force
	350	parameter (default), so we must identify the chip. */
	351	if (kind < 0) {
	352	u8 config = i2c_smbus_read_byte_data(new_client,
	353	LM92_REG_CONFIG);
	354	u16 man_id = i2c_smbus_read_word_data(new_client,
	355	LM92_REG_MAN_ID);
	356
	357	if ((config & 0xe0) == 0x00
	358	&& man_id == 0x0180) {
	359	pr_info("lm92: Found National Semiconductor LM92 chip\n");
	360	kind = lm92;
	361	} else
	362	if (max6635_check(new_client)) {
	363	pr_info("lm92: Found Maxim MAX6635 chip\n");
	364	kind = lm92; /* No separate prefix */
	365	}
	366	else
	367	goto exit_free;
	368	} else
	369	if (kind == 0) /* Default to an LM92 if forced */
	370	kind = lm92;
	371
	372	/* Give it the proper name */
	373	if (kind == lm92) {
	374	name = "lm92";
	375	} else { /* Supposedly cannot happen */
	376	dev_dbg(&new_client->dev, "Kind out of range?\n");
	377	goto exit_free;
	378	}
	379
	380	/* Fill in the remaining client fields */
	381	strlcpy(new_client->name, name, I2C_NAME_SIZE);
	382	data->valid = 0;
9a61bf63	383	mutex_init(&data->update_lock);
1da177e4 LT	384
	385	/* Tell the i2c subsystem a new client has arrived */
	386	if ((err = i2c_attach_client(new_client)))
	387	goto exit_free;
	388
	389	/* Initialize the chipset */
	390	lm92_init_client(new_client);
	391
	392	/* Register sysfs hooks */
0501a381 MH	393	if ((err = sysfs_create_group(&new_client->dev.kobj, &lm92_group)))
	394	goto exit_detach;
	395
1beeffe4 TJ	396	data->hwmon_dev = hwmon_device_register(&new_client->dev);
	397	if (IS_ERR(data->hwmon_dev)) {
	398	err = PTR_ERR(data->hwmon_dev);
0501a381	399	goto exit_remove;
943b0830 MH	400	}
943b0830 MH	401
1da177e4 LT	402	return 0;
1da177e4 LT	403
0501a381 MH	404	exit_remove:
0501a381 MH	405	sysfs_remove_group(&new_client->dev.kobj, &lm92_group);
943b0830 MH	406	exit_detach:
943b0830 MH	407	i2c_detach_client(new_client);
1da177e4 LT	408	exit_free:
	409	kfree(data);
	410	exit:
	411	return err;
	412	}
	413
	414	static int lm92_attach_adapter(struct i2c_adapter *adapter)
	415	{
	416	if (!(adapter->class & I2C_CLASS_HWMON))
	417	return 0;
2ed2dc3c	418	return i2c_probe(adapter, &addr_data, lm92_detect);
1da177e4 LT	419	}
	420
	421	static int lm92_detach_client(struct i2c_client *client)
	422	{
943b0830	423	struct lm92_data *data = i2c_get_clientdata(client);
1da177e4 LT	424	int err;
1da177e4 LT	425
1beeffe4	426	hwmon_device_unregister(data->hwmon_dev);
0501a381	427	sysfs_remove_group(&client->dev.kobj, &lm92_group);
943b0830	428
7bef5594	429	if ((err = i2c_detach_client(client)))
1da177e4	430	return err;
1da177e4	431
943b0830	432	kfree(data);
1da177e4 LT	433	return 0;
	434	}
	435
	436
	437	/*
	438	* Module and driver stuff
	439	*/
	440
	441	static struct i2c_driver lm92_driver = {
cdaf7934	442	.driver = {
cdaf7934 LR	443	.name = "lm92",
cdaf7934 LR	444	},
1da177e4 LT	445	.attach_adapter = lm92_attach_adapter,
	446	.detach_client = lm92_detach_client,
	447	};
	448
	449	static int __init sensors_lm92_init(void)
	450	{
	451	return i2c_add_driver(&lm92_driver);
	452	}
	453
	454	static void __exit sensors_lm92_exit(void)
	455	{
	456	i2c_del_driver(&lm92_driver);
	457	}
	458
	459	MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>");
	460	MODULE_DESCRIPTION("LM92/MAX6635 driver");
	461	MODULE_LICENSE("GPL");
	462
	463	module_init(sensors_lm92_init);
	464	module_exit(sensors_lm92_exit);