Commit beb1b6bb authored by Steven King's avatar Steven King Committed by Jean Delvare

hwmon: Driver for TI TMP102 temperature sensor

Driver for the TI TMP102.

The TI TMP102 is similar to the LM75.  It differs from the LM75 by
having a 16-bit conf register and the temp registers have a minimum
resolution of 12 bits; the extended conf register can select 13-bit
resolution (which this driver does) and also change the update rate
(which this driver currently doesn't use).

[JD: Fix tmp102_exit tag, must be __exit, not __init.]
Signed-off-by: default avatarSteven King <>
Signed-off-by: default avatarJean Delvare <>
parent dac6831e
Kernel driver tmp102
Supported chips:
* Texas Instruments TMP102
Prefix: 'tmp102'
Addresses scanned: I2C 0x48 0x49 0x4a 0x4b
Steven King <>
The Texas Instruments TMP102 implements one temperature sensor. Limits can be
set through the Overtemperature Shutdown register and Hysteresis register. The
sensor is accurate to 0.5 degrees over the range of -25 to +85 C, and to 1.0
degrees from -40 to +125 C. Resolution of the sensor is 0.0625 degree. The
operating temperature has a minimum of -55 C and a maximum of +150 C.
The TMP102 has a programmable update rate that can select between 8, 4, 1, and
0.5 Hz. (Currently the driver only supports the default of 4 Hz).
The driver provides the common sysfs-interface for temperatures (see
/Documentation/hwmon/sysfs-interface under Temperatures).
......@@ -842,6 +842,16 @@ config SENSORS_THMC50
This driver can also be built as a module. If so, the module
will be called thmc50.
config SENSORS_TMP102
tristate "Texas Instruments TMP102 and compatibles"
depends on I2C && EXPERIMENTAL
If you say yes here you get support for Texas Instruments TMP102
sensor chips.
This driver can also be built as a module. If so, the module
will be called tmp102.
config SENSORS_TMP401
tristate "Texas Instruments TMP401 and compatibles"
depends on I2C && EXPERIMENTAL
......@@ -91,6 +91,7 @@ obj-$(CONFIG_SENSORS_SMSC47M1) += smsc47m1.o
obj-$(CONFIG_SENSORS_SMSC47M192)+= smsc47m192.o
obj-$(CONFIG_SENSORS_AMC6821) += amc6821.o
obj-$(CONFIG_SENSORS_THMC50) += thmc50.o
obj-$(CONFIG_SENSORS_TMP102) += tmp102.o
obj-$(CONFIG_SENSORS_TMP401) += tmp401.o
obj-$(CONFIG_SENSORS_TMP421) += tmp421.o
obj-$(CONFIG_SENSORS_VIA_CPUTEMP)+= via-cputemp.o
/* Texas Instruments TMP102 SMBUS temperature sensor driver
* Copyright 2010 Steven King <>
* 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
* 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., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 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>
#include <linux/delay.h>
#define DRIVER_NAME "tmp102"
#define TMP102_TEMP_REG 0x00
#define TMP102_CONF_REG 0x01
/* note: these bit definitions are byte swapped */
#define TMP102_CONF_SD 0x0100
#define TMP102_CONF_TM 0x0200
#define TMP102_CONF_POL 0x0400
#define TMP102_CONF_F0 0x0800
#define TMP102_CONF_F1 0x1000
#define TMP102_CONF_R0 0x2000
#define TMP102_CONF_R1 0x4000
#define TMP102_CONF_OS 0x8000
#define TMP102_CONF_EM 0x0010
#define TMP102_CONF_AL 0x0020
#define TMP102_CONF_CR0 0x0040
#define TMP102_CONF_CR1 0x0080
#define TMP102_TLOW_REG 0x02
#define TMP102_THIGH_REG 0x03
struct tmp102 {
struct device *hwmon_dev;
struct mutex lock;
unsigned long last_update;
int temp[3];
/* the TMP102 registers are big endian so we have to swab16 the values */
static int tmp102_read_reg(struct i2c_client *client, u8 reg)
int result = i2c_smbus_read_word_data(client, reg);
return result < 0 ? result : swab16(result);
static int tmp102_write_reg(struct i2c_client *client, u8 reg, u16 val)
return i2c_smbus_write_word_data(client, reg, swab16(val));
/* convert left adjusted 13bit TMP102 register value to miliCelsius */
static int tmp102_reg_to_mC(s16 val)
return (val * 1000) / 128;
/* convert miliCelsius to left adjusted 13bit TMP102 register value */
static u16 tmp102_mC_to_reg(int val)
return (val * 128) / 1000;
static const u8 tmp102_reg[] = {
static struct tmp102 *tmp102_update_device(struct i2c_client *client)
struct tmp102 *tmp102 = i2c_get_clientdata(client);
if (time_after(jiffies, tmp102->last_update + HZ / 4)) {
int i;
for (i = 0; i < ARRAY_SIZE(tmp102->temp); ++i) {
int status = tmp102_read_reg(client, tmp102_reg[i]);
if (status > -1)
tmp102->temp[i] = tmp102_reg_to_mC(status);
tmp102->last_update = jiffies;
return tmp102;
static ssize_t tmp102_show_temp(struct device *dev,
struct device_attribute *attr,
char *buf)
struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
struct tmp102 *tmp102 = tmp102_update_device(to_i2c_client(dev));
return sprintf(buf, "%d\n", tmp102->temp[sda->index]);
static ssize_t tmp102_set_temp(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
struct i2c_client *client = to_i2c_client(dev);
struct tmp102 *tmp102 = i2c_get_clientdata(client);
long val;
int status = 0;
if ((strict_strtol(buf, 10, &val) < 0) || (abs(val) > 150000))
return -EINVAL;
if (tmp102->temp[sda->index] != val) {
tmp102->temp[sda->index] = val;
status = tmp102_write_reg(client, tmp102_reg[sda->index],
return status ? : count;
static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, tmp102_show_temp, NULL , 0);
static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO, tmp102_show_temp,
tmp102_set_temp, 1);
static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, tmp102_show_temp,
tmp102_set_temp, 2);
static struct attribute *tmp102_attributes[] = {
static const struct attribute_group tmp102_attr_group = {
.attrs = tmp102_attributes,
#define TMP102_CONFIG (TMP102_CONF_TM | TMP102_CONF_EM | TMP102_CONF_CR1)
#define TMP102_CONFIG_RD_ONLY (TMP102_CONF_R0 | TMP102_CONF_R1 | TMP102_CONF_AL)
static int __devinit tmp102_probe(struct i2c_client *client,
const struct i2c_device_id *id)
struct tmp102 *tmp102;
int status;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA |
dev_dbg(&client->dev, "adapter doesnt support SMBUS\n");
return -ENODEV;
tmp102 = kzalloc(sizeof(*tmp102), GFP_KERNEL);
if (!tmp102) {
dev_dbg(&client->dev, "kzalloc failed\n");
return -ENOMEM;
i2c_set_clientdata(client, tmp102);
tmp102_write_reg(client, TMP102_CONF_REG, TMP102_CONFIG);
status = tmp102_read_reg(client, TMP102_CONF_REG);
if (status < 0) {
dev_dbg(&client->dev, "error reading config register\n");
goto fail0;
status &= ~TMP102_CONFIG_RD_ONLY;
if (status != TMP102_CONFIG) {
dev_dbg(&client->dev, "could not verify config settings\n");
status = -EIO;
goto fail0;
tmp102->last_update = jiffies - HZ;
status = sysfs_create_group(&client->dev.kobj, &tmp102_attr_group);
if (status) {
dev_dbg(&client->dev, "could not create sysfs files\n");
goto fail0;
tmp102->hwmon_dev = hwmon_device_register(&client->dev);
if (IS_ERR(tmp102->hwmon_dev)) {
dev_dbg(&client->dev, "unable to register hwmon device\n");
status = PTR_ERR(tmp102->hwmon_dev);
goto fail1;
dev_info(&client->dev, "initialized\n");
return 0;
sysfs_remove_group(&client->dev.kobj, &tmp102_attr_group);
i2c_set_clientdata(client, NULL);
return 0;
static int __devexit tmp102_remove(struct i2c_client *client)
struct tmp102 *tmp102 = i2c_get_clientdata(client);
/* shutdown the chip */
tmp102_write_reg(client, TMP102_CONF_REG, TMP102_CONF_SD);
sysfs_remove_group(&client->dev.kobj, &tmp102_attr_group);
i2c_set_clientdata(client, NULL);
return 0;
#ifdef CONFIG_PM
static int tmp102_suspend(struct device *dev)
struct i2c_client *client = to_i2c_client(dev);
tmp102_write_reg(client, TMP102_CONF_REG, TMP102_CONF_SD);
return 0;
static int tmp102_resume(struct device *dev)
struct i2c_client *client = to_i2c_client(dev);
tmp102_write_reg(client, TMP102_CONF_REG, TMP102_CONFIG);
return 0;
static const struct dev_pm_ops tmp102_dev_pm_ops = {
.suspend = tmp102_suspend,
.resume = tmp102_resume,
#define TMP102_DEV_PM_OPS (&tmp102_dev_pm_ops)
#define TMP102_DEV_PM_OPS NULL
#endif /* CONFIG_PM */
static const unsigned short normal_i2c[] = {
0x48, 0x49, 0x4a, 0x4b, I2C_CLIENT_END
static const struct i2c_device_id tmp102_id[] = {
{ }
static struct i2c_driver tmp102_driver = { = DRIVER_NAME, = TMP102_DEV_PM_OPS,
.class = I2C_CLASS_HWMON,
.probe = tmp102_probe,
.remove = __devexit_p(tmp102_remove),
.id_table = tmp102_id,
.address_list = normal_i2c,
static int __init tmp102_init(void)
return i2c_add_driver(&tmp102_driver);
static void __exit tmp102_exit(void)
MODULE_AUTHOR("Steven King <>");
MODULE_DESCRIPTION("Texas Instruments TMP102 temperature sensor driver");
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