/*
* LM73 Sensor driver
* Based on LM75
*
* Copyright (C) 2007, CenoSYS (www.cenosys.com).
* Copyright (C) 2009, Bollore telecom (www.bolloretelecom.eu).
*
* Guillaume Ligneul <guillaume.ligneul@gmail.com>
* Adrien Demarez <adrien.demarez@bolloretelecom.eu>
* Jeremy Laine <jeremy.laine@bolloretelecom.eu>
*
* This software program is licensed subject to the GNU General Public License
* (GPL).Version 2,June 1991, available at
* http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
*/
#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>
/* Addresses scanned */
static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4c,
0x4d, 0x4e, I2C_CLIENT_END };
/* LM73 registers */
#define LM73_REG_INPUT 0x00
#define LM73_REG_CONF 0x01
#define LM73_REG_MAX 0x02
#define LM73_REG_MIN 0x03
#define LM73_REG_CTRL 0x04
#define LM73_REG_ID 0x07
#define LM73_ID 0x9001 /* or 0x190 after a swab16() */
#define DRVNAME "lm73"
#define LM73_TEMP_MIN (-40)
#define LM73_TEMP_MAX 150
/*-----------------------------------------------------------------------*/
static ssize_t set_temp(struct device *dev, struct device_attribute *da,
const char *buf, size_t count)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
struct i2c_client *client = to_i2c_client(dev);
long temp;
short value;
int status = strict_strtol(buf, 10, &temp);
if (status < 0)
return status;
/* Write value */
value = (short) SENSORS_LIMIT(temp/250, (LM73_TEMP_MIN*4),
(LM73_TEMP_MAX*4)) << 5;
i2c_smbus_write_word_data(client, attr->index, swab16(value));
return count;
}
static ssize_t show_temp(struct device *dev, struct device_attribute *da,
char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
struct i2c_client *client = to_i2c_client(dev);
/* use integer division instead of equivalent right shift to
guarantee arithmetic shift and preserve the sign */
int temp = ((s16) (swab16(i2c_smbus_read_word_data(client,
attr->index)))*250) / 32;
return sprintf(buf, "%d\n", temp);
}
/*-----------------------------------------------------------------------*/
/* sysfs attributes for hwmon */
static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,
show_temp, set_temp, LM73_REG_MAX);
static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO,
show_temp, set_temp, LM73_REG_MIN);
static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO,
show_temp, NULL, LM73_REG_INPUT);
static struct attribute *lm73_attributes[] = {
&sensor_dev_attr_temp1_input.dev_attr.attr,
&sensor_dev_attr_temp1_max.dev_attr.attr,
&sensor_dev_attr_temp1_min.dev_attr.attr,
NULL
};
static const struct attribute_group lm73_group = {
.attrs = lm73_attributes,
};
/*-----------------------------------------------------------------------*/
/* device probe and removal */
static int
lm73_probe(struct i2c_client *client, const struct i2c_device_id *id)
{
struct device *hwmon_dev;
int status;
/* Register sysfs hooks */
status = sysfs_create_group(&client->dev.kobj, &lm73_group);
if (status)
return status;
hwmon_dev = hwmon_device_register(&client->dev);
if (IS_ERR(hwmon_dev)) {
status = PTR_ERR(hwmon_dev);
goto exit_remove;
}
i2c_set_clientdata(client, hwmon_dev);
dev_info(&client->dev, "%s: sensor '%s'\n",
dev_name(hwmon_dev), client->name);
return 0;
exit_remove:
sysfs_remove_group(&client->dev.kobj, &lm73_group);
return status;
}
static int lm73_remove(struct i2c_client *client)
{
struct device *hwmon_dev = i2c_get_clientdata(client);
hwmon_device_unregister(hwmon_dev);
sysfs_remove_group(&client->dev.kobj, &lm73_group);
i2c_set_clientdata(client, NULL);
return 0;
}
static const struct i2c_device_id lm73_ids[] = {
{ "lm73", 0 },
{ /* LIST END */ }
};
MODULE_DEVICE_TABLE(i2c, lm73_ids);
/* Return 0 if detection is successful, -ENODEV otherwise */
static int lm73_detect(struct i2c_client *new_client,
struct i2c_board_info *info)
{
struct i2c_adapter *adapter = new_client->adapter;
u16 id;
u8 ctrl;
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
I2C_FUNC_SMBUS_WORD_DATA))
return -ENODEV;
/* Check device ID */
id = i2c_smbus_read_word_data(new_client, LM73_REG_ID);
ctrl = i2c_smbus_read_byte_data(new_client, LM73_REG_CTRL);
if ((id != LM73_ID) || (ctrl & 0x10))
return -ENODEV;
strlcpy(info->type, "lm73", I2C_NAME_SIZE);
return 0;
}
static struct i2c_driver lm73_driver = {
.class = I2C_CLASS_HWMON,
.driver = {
.name = "lm73",
},
.probe = lm73_probe,
.remove = lm73_remove,
.id_table = lm73_ids,
.detect = lm73_detect,
.address_list = normal_i2c,
};
/* module glue */
static int __init sensors_lm73_init(void)
{
return i2c_add_driver(&lm73_driver);
}
static void __exit sensors_lm73_exit(void)
{
i2c_del_driver(&lm73_driver);
}
MODULE_AUTHOR("Guillaume Ligneul <guillaume.ligneul@gmail.com>");
MODULE_DESCRIPTION("LM73 driver");
MODULE_LICENSE("GPL");
module_init(sensors_lm73_init);
module_exit(sensors_lm73_exit);
