/*
* lm83.c - Part of lm_sensors, Linux kernel modules for hardware
* monitoring
* Copyright (C) 2003-2005 Jean Delvare <khali@linux-fr.org>
*
* Heavily inspired from the lm78, lm75 and adm1021 drivers. The LM83 is
* a sensor chip made by National Semiconductor. It reports up to four
* temperatures (its own plus up to three external ones) with a 1 deg
* resolution and a 3-4 deg accuracy. Complete datasheet can be obtained
* from National's website at:
* http://www.national.com/pf/LM/LM83.html
* Since the datasheet omits to give the chip stepping code, I give it
* here: 0x03 (at register 0xff).
*
* 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-sysfs.h>
#include <linux/hwmon.h>
#include <linux/err.h>
/*
* Addresses to scan
* Address is selected using 2 three-level pins, resulting in 9 possible
* addresses.
*/
static unsigned short normal_i2c[] = { 0x18, 0x19, 0x1a,
0x29, 0x2a, 0x2b,
0x4c, 0x4d, 0x4e,
I2C_CLIENT_END };
/*
* Insmod parameters
*/
I2C_CLIENT_INSMOD_1(lm83);
/*
* The LM83 registers
* Manufacturer ID is 0x01 for National Semiconductor.
*/
#define LM83_REG_R_MAN_ID 0xFE
#define LM83_REG_R_CHIP_ID 0xFF
#define LM83_REG_R_CONFIG 0x03
#define LM83_REG_W_CONFIG 0x09
#define LM83_REG_R_STATUS1 0x02
#define LM83_REG_R_STATUS2 0x35
#define LM83_REG_R_LOCAL_TEMP 0x00
#define LM83_REG_R_LOCAL_HIGH 0x05
#define LM83_REG_W_LOCAL_HIGH 0x0B
#define LM83_REG_R_REMOTE1_TEMP 0x30
#define LM83_REG_R_REMOTE1_HIGH 0x38
#define LM83_REG_W_REMOTE1_HIGH 0x50
#define LM83_REG_R_REMOTE2_TEMP 0x01
#define LM83_REG_R_REMOTE2_HIGH 0x07
#define LM83_REG_W_REMOTE2_HIGH 0x0D
#define LM83_REG_R_REMOTE3_TEMP 0x31
#define LM83_REG_R_REMOTE3_HIGH 0x3A
#define LM83_REG_W_REMOTE3_HIGH 0x52
#define LM83_REG_R_TCRIT 0x42
#define LM83_REG_W_TCRIT 0x5A
/*
* Conversions and various macros
* The LM83 uses signed 8-bit values with LSB = 1 degree Celsius.
*/
#define TEMP_FROM_REG(val) ((val) * 1000)
#define TEMP_TO_REG(val) ((val) <= -128000 ? -128 : \
(val) >= 127000 ? 127 : \
(val) < 0 ? ((val) - 500) / 1000 : \
((val) + 500) / 1000)
static const u8 LM83_REG_R_TEMP[] = {
LM83_REG_R_LOCAL_TEMP,
LM83_REG_R_REMOTE1_TEMP,
LM83_REG_R_REMOTE2_TEMP,
LM83_REG_R_REMOTE3_TEMP,
LM83_REG_R_LOCAL_HIGH,
LM83_REG_R_REMOTE1_HIGH,
LM83_REG_R_REMOTE2_HIGH,
LM83_REG_R_REMOTE3_HIGH,
LM83_REG_R_TCRIT,
};
static const u8 LM83_REG_W_HIGH[] = {
LM83_REG_W_LOCAL_HIGH,
LM83_REG_W_REMOTE1_HIGH,
LM83_REG_W_REMOTE2_HIGH,
LM83_REG_W_REMOTE3_HIGH,
LM83_REG_W_TCRIT,
};
/*
* Functions declaration
*/
static int lm83_attach_adapter(struct i2c_adapter *adapter);
static int lm83_detect(struct i2c_adapter *adapter, int address, int kind);
static int lm83_detach_client(struct i2c_client *client);
static struct lm83_data *lm83_update_device(struct device *dev);
/*
* Driver data (common to all clients)
*/
static struct i2c_driver lm83_driver = {
.owner = THIS_MODULE,
.name = "lm83",
.id = I2C_DRIVERID_LM83,
.flags = I2C_DF_NOTIFY,
.attach_adapter = lm83_attach_adapter,
.detach_client = lm83_detach_client,
};
/*
* Client data (each client gets its own)
*/
struct lm83_data {
struct i2c_client client;
struct class_device *class_dev;
struct semaphore update_lock;
char valid; /* zero until following fields are valid */
unsigned long last_updated; /* in jiffies */
/* registers values */
s8 temp[9]; /* 0..3: input 1-4,
4..7: high limit 1-4,
8 : critical limit */
u16 alarms; /* bitvector, combined */
};
/*
* Sysfs stuff
*/
static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
struct lm83_data *data = lm83_update_device(dev);
return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[attr->index]));
}
static ssize_t set_temp(struct device *dev, struct device_attribute *devattr,
const char *buf, size_t count)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
struct i2c_client *client = to_i2c_client(dev);
struct lm83_data *data = i2c_get_clientdata(client);
long val = simple_strtol(buf, NULL, 10);
int nr = attr->index;
down(&data->update_lock);
data->temp[nr] = TEMP_TO_REG(val);
i2c_smbus_write_byte_data(client, LM83_REG_W_HIGH[nr - 4],
data->temp[nr]);
up(&data->update_lock);
return count;
}
static ssize_t show_alarms(struct device *dev, struct device_attribute *dummy,
char *buf)
{
struct lm83_data *data = lm83_update_device(dev);
return sprintf(buf, "%d\n", data->alarms);
}
static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, 1);
static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp, NULL, 2);
static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp, NULL, 3);
static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp,
set_temp, 4);
static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp,
set_temp, 5);
static SENSOR_DEVICE_ATTR(temp3_max, S_IWUSR | S_IRUGO, show_temp,
set_temp, 6);
static SENSOR_DEVICE_ATTR(temp4_max, S_IWUSR | S_IRUGO, show_temp,
set_temp, 7);
static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, show_temp, NULL, 8);
static SENSOR_DEVICE_ATTR(temp2_crit, S_IRUGO, show_temp, NULL, 8);
static SENSOR_DEVICE_ATTR(temp3_crit, S_IWUSR | S_IRUGO, show_temp,
set_temp, 8);
static SENSOR_DEVICE_ATTR(temp4_crit, S_IRUGO, show_temp, NULL, 8);
static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
/*
* Real code
*/
static int lm83_attach_adapter(struct i2c_adapter *adapter)
{
if (!(adapter->class & I2C_CLASS_HWMON))
return 0;
return i2c_probe(adapter, &addr_data, lm83_detect);
}
/*
* The following function does more than just detection. If detection
* succeeds, it also registers the new chip.
*/
static int lm83_detect(struct i2c_adapter *adapter, int address, int kind)
{
struct i2c_client *new_client;
struct lm83_data *data;
int err = 0;
const char *name = "";
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
goto exit;
if (!(data = kzalloc(sizeof(struct lm83_data), GFP_KERNEL))) {
err = -ENOMEM;
goto exit;
}
/* The common I2C client data is placed right after the
* LM83-specific data. */
new_client = &data->client;
i2c_set_clientdata(new_client, data);
new_client->addr = address;
new_client->adapter = adapter;
new_client->driver = &lm83_driver;
new_client->flags = 0;
/* Now we do the detection and identification. A negative kind
* means that the driver was loaded with no force parameter
* (default), so we must both detect and identify the chip
* (actually there is only one possible kind of chip for now, LM83).
* A zero kind means that the driver was loaded with the force
* parameter, the detection step shall be skipped. A positive kind
* means that the driver was loaded with the force parameter and a
* given kind of chip is requested, so both the detection and the
* identification steps are skipped. */
/* Default to an LM83 if forced */
if (kind == 0)
kind = lm83;
if (kind < 0) { /* detection */
if (((i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS1)
& 0xA8) != 0x00) ||
((i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS2)
& 0x48) != 0x00) ||
((i2c_smbus_read_byte_data(new_client, LM83_REG_R_CONFIG)
& 0x41) != 0x00)) {
dev_dbg(&adapter->dev,
"LM83 detection failed at 0x%02x.\n", address);
goto exit_free;
}
}
if (kind <= 0) { /* identification */
u8 man_id, chip_id;
man_id = i2c_smbus_read_byte_data(new_client,
LM83_REG_R_MAN_ID);
chip_id = i2c_smbus_read_byte_data(new_client,
LM83_REG_R_CHIP_ID);
if (man_id == 0x01) { /* National Semiconductor */
if (chip_id == 0x03) {
kind = lm83;
}
}
if (kind <= 0) { /* identification failed */
dev_info(&adapter->dev,
"Unsupported chip (man_id=0x%02X, "
"chip_id=0x%02X).\n", man_id, chip_id);
goto exit_free;
}
}
if (kind == lm83) {
name = "lm83";
}
/* We can fill in the remaining client fields */
strlcpy(new_client->name, name, I2C_NAME_SIZE);
data->valid = 0;
init_MUTEX(&data->update_lock);
/* Tell the I2C layer a new client has arrived */
if ((err = i2c_attach_client(new_client)))
goto exit_free;
/*
* Initialize the LM83 chip
* (Nothing to do for this one.)
*/
/* Register sysfs hooks */
data->class_dev = hwmon_device_register(&new_client->dev);
if (IS_ERR(data->class_dev)) {
err = PTR_ERR(data->class_dev);
goto exit_detach;
}
device_create_file(&new_client->dev,
&sensor_dev_attr_temp1_input.dev_attr);
device_create_file(&new_client->dev,
&sensor_dev_attr_temp2_input.dev_attr);
device_create_file(&new_client->dev,
&sensor_dev_attr_temp3_input.dev_attr);
device_create_file(&new_client->dev,
&sensor_dev_attr_temp4_input.dev_attr);
device_create_file(&new_client->dev,
&sensor_dev_attr_temp1_max.dev_attr);
device_create_file(&new_client->dev,
&sensor_dev_attr_temp2_max.dev_attr);
device_create_file(&new_client->dev,
&sensor_dev_attr_temp3_max.dev_attr);
device_create_file(&new_client->dev,
&sensor_dev_attr_temp4_max.dev_attr);
device_create_file(&new_client->dev,
&sensor_dev_attr_temp1_crit.dev_attr);
device_create_file(&new_client->dev,
&sensor_dev_attr_temp2_crit.dev_attr);
device_create_file(&new_client->dev,
&sensor_dev_attr_temp3_crit.dev_attr);
device_create_file(&new_client->dev,
&sensor_dev_attr_temp4_crit.dev_attr);
device_create_file(&new_client->dev, &dev_attr_alarms);
return 0;
exit_detach:
i2c_detach_client(new_client);
exit_free:
kfree(data);
exit:
return err;
}
static int lm83_detach_client(struct i2c_client *client)
{
struct lm83_data *data = i2c_get_clientdata(client);
int err;
hwmon_device_unregister(data->class_dev);
if ((err = i2c_detach_client(client)))
return err;
kfree(data);
return 0;
}
static struct lm83_data *lm83_update_device(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct lm83_data *data = i2c_get_clientdata(client);
down(&data->update_lock);
if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) {
int nr;
dev_dbg(&client->dev, "Updating lm83 data.\n");
for (nr = 0; nr < 9; nr++) {
data->temp[nr] =
i2c_smbus_read_byte_data(client,
LM83_REG_R_TEMP[nr]);
}
data->alarms =
i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS1)
+ (i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS2)
<< 8);
data->last_updated = jiffies;
data->valid = 1;
}
up(&data->update_lock);
return data;
}
static int __init sensors_lm83_init(void)
{
return i2c_add_driver(&lm83_driver);
}
static void __exit sensors_lm83_exit(void)
{
i2c_del_driver(&lm83_driver);
}
MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>");
MODULE_DESCRIPTION("LM83 driver");
MODULE_LICENSE("GPL");
module_init(sensors_lm83_init);
module_exit(sensors_lm83_exit);
