/*
* lm95241.c - Part of lm_sensors, Linux kernel modules for hardware
* monitoring
* Copyright (C) 2008 Davide Rizzo <elpa-rizzo@gmail.com>
*
* Based on the max1619 driver. The LM95241 is a sensor chip made by National
* Semiconductors.
* It reports up to three temperatures (its own plus up to
* two external ones). Complete datasheet can be
* obtained from National's website at:
* http://www.national.com/ds.cgi/LM/LM95241.pdf
*
* 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/err.h>
#include <linux/mutex.h>
#include <linux/sysfs.h>
static const unsigned short normal_i2c[] = {
0x19, 0x2a, 0x2b, I2C_CLIENT_END};
/* Insmod parameters */
I2C_CLIENT_INSMOD_1(lm95241);
/* LM95241 registers */
#define LM95241_REG_R_MAN_ID 0xFE
#define LM95241_REG_R_CHIP_ID 0xFF
#define LM95241_REG_R_STATUS 0x02
#define LM95241_REG_RW_CONFIG 0x03
#define LM95241_REG_RW_REM_FILTER 0x06
#define LM95241_REG_RW_TRUTHERM 0x07
#define LM95241_REG_W_ONE_SHOT 0x0F
#define LM95241_REG_R_LOCAL_TEMPH 0x10
#define LM95241_REG_R_REMOTE1_TEMPH 0x11
#define LM95241_REG_R_REMOTE2_TEMPH 0x12
#define LM95241_REG_R_LOCAL_TEMPL 0x20
#define LM95241_REG_R_REMOTE1_TEMPL 0x21
#define LM95241_REG_R_REMOTE2_TEMPL 0x22
#define LM95241_REG_RW_REMOTE_MODEL 0x30
/* LM95241 specific bitfields */
#define CFG_STOP 0x40
#define CFG_CR0076 0x00
#define CFG_CR0182 0x10
#define CFG_CR1000 0x20
#define CFG_CR2700 0x30
#define R1MS_SHIFT 0
#define R2MS_SHIFT 2
#define R1MS_MASK (0x01 << (R1MS_SHIFT))
#define R2MS_MASK (0x01 << (R2MS_SHIFT))
#define R1DF_SHIFT 1
#define R2DF_SHIFT 2
#define R1DF_MASK (0x01 << (R1DF_SHIFT))
#define R2DF_MASK (0x01 << (R2DF_SHIFT))
#define R1FE_MASK 0x01
#define R2FE_MASK 0x05
#define TT1_SHIFT 0
#define TT2_SHIFT 4
#define TT_OFF 0
#define TT_ON 1
#define TT_MASK 7
#define MANUFACTURER_ID 0x01
#define DEFAULT_REVISION 0xA4
/* Conversions and various macros */
#define TEMP_FROM_REG(val_h, val_l) (((val_h) & 0x80 ? (val_h) - 0x100 : \
(val_h)) * 1000 + (val_l) * 1000 / 256)
/* Functions declaration */
static void lm95241_init_client(struct i2c_client *client);
static struct lm95241_data *lm95241_update_device(struct device *dev);
/* Client data (each client gets its own) */
struct lm95241_data {
struct device *hwmon_dev;
struct mutex update_lock;
unsigned long last_updated, rate; /* in jiffies */
char valid; /* zero until following fields are valid */
/* registers values */
u8 local_h, local_l; /* local */
u8 remote1_h, remote1_l; /* remote1 */
u8 remote2_h, remote2_l; /* remote2 */
u8 config, model, trutherm;
};
/* Sysfs stuff */
#define show_temp(value) \
static ssize_t show_##value(struct device *dev, \
struct device_attribute *attr, char *buf) \
{ \
struct lm95241_data *data = lm95241_update_device(dev); \
snprintf(buf, PAGE_SIZE - 1, "%d\n", \
TEMP_FROM_REG(data->value##_h, data->value##_l)); \
return strlen(buf); \
}
show_temp(local);
show_temp(remote1);
show_temp(remote2);
static ssize_t show_rate(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct lm95241_data *data = lm95241_update_device(dev);
snprintf(buf, PAGE_SIZE - 1, "%lu\n", 1000 * data->rate / HZ);
return strlen(buf);
}
static ssize_t set_rate(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct i2c_client *client = to_i2c_client(dev);
struct lm95241_data *data = i2c_get_clientdata(client);
strict_strtol(buf, 10, &data->rate);
data->rate = data->rate * HZ / 1000;
return count;
}
#define show_type(flag) \
static ssize_t show_type##flag(struct device *dev, \
struct device_attribute *attr, char *buf) \
{ \
struct i2c_client *client = to_i2c_client(dev); \
struct lm95241_data *data = i2c_get_clientdata(client); \
\
snprintf(buf, PAGE_SIZE - 1, \
data->model & R##flag##MS_MASK ? "1\n" : "2\n"); \
return strlen(buf); \
}
show_type(1);
show_type(2);
#define show_min(flag) \
static ssize_t show_min##flag(struct device *dev, \
struct device_attribute *attr, char *buf) \
{ \
struct i2c_client *client = to_i2c_client(dev); \
struct lm95241_data *data = i2c_get_clientdata(client); \
\
snprintf(buf, PAGE_SIZE - 1, \
data->config & R##flag##DF_MASK ? \
"-127000\n" : "0\n"); \
return strlen(buf); \
}
show_min(1);
show_min(2);
#define show_max(flag) \
static ssize_t show_max##flag(struct device *dev, \
struct device_attribute *attr, char *buf) \
{ \
struct i2c_client *client = to_i2c_client(dev); \
struct lm95241_data *data = i2c_get_clientdata(client); \
\
snprintf(buf, PAGE_SIZE - 1, \
data->config & R##flag##DF_MASK ? \
"127000\n" : "255000\n"); \
return strlen(buf); \
}
show_max(1);
show_max(2);
#define set_type(flag) \
static ssize_t set_type##flag(struct device *dev, \
struct device_attribute *attr, \
const char *buf, size_t count) \
{ \
struct i2c_client *client = to_i2c_client(dev); \
struct lm95241_data *data = i2c_get_clientdata(client); \
\
long val; \
strict_strtol(buf, 10, &val); \
\
if ((val == 1) || (val == 2)) { \
\
mutex_lock(&data->update_lock); \
\
data->trutherm &= ~(TT_MASK << TT##flag##_SHIFT); \
if (val == 1) { \
data->model |= R##flag##MS_MASK; \
data->trutherm |= (TT_ON << TT##flag##_SHIFT); \
} \
else { \
data->model &= ~R##flag##MS_MASK; \
data->trutherm |= (TT_OFF << TT##flag##_SHIFT); \
} \
\
data->valid = 0; \
\
i2c_smbus_write_byte_data(client, LM95241_REG_RW_REMOTE_MODEL, \
data->model); \
i2c_smbus_write_byte_data(client, LM95241_REG_RW_TRUTHERM, \
data->trutherm); \
\
mutex_unlock(&data->update_lock); \
\
} \
return count; \
}
set_type(1);
set_type(2);
#define set_min(flag) \
static ssize_t set_min##flag(struct device *dev, \
struct device_attribute *devattr, const char *buf, size_t count) \
{ \
struct i2c_client *client = to_i2c_client(dev); \
struct lm95241_data *data = i2c_get_clientdata(client); \
\
long val; \
strict_strtol(buf, 10, &val); \
\
mutex_lock(&data->update_lock); \
\
if (val < 0) \
data->config |= R##flag##DF_MASK; \
else \
data->config &= ~R##flag##DF_MASK; \
\
data->valid = 0; \
\
i2c_smbus_write_byte_data(client, LM95241_REG_RW_CONFIG, \
data->config); \
\
mutex_unlock(&data->update_lock); \
\
return count; \
}
set_min(1);
set_min(2);
#define set_max(flag) \
static ssize_t set_max##flag(struct device *dev, \
struct device_attribute *devattr, const char *buf, size_t count) \
{ \
struct i2c_client *client = to_i2c_client(dev); \
struct lm95241_data *data = i2c_get_clientdata(client); \
\
long val; \
strict_strtol(buf, 10, &val); \
\
mutex_lock(&data->update_lock); \
\
if (val <= 127000) \
data->config |= R##flag##DF_MASK; \
else \
data->config &= ~R##flag##DF_MASK; \
\
data->valid = 0; \
\
i2c_smbus_write_byte_data(client, LM95241_REG_RW_CONFIG, \
data->config); \
\
mutex_unlock(&data->update_lock); \
\
return count; \
}
set_max(1);
set_max(2);
static DEVICE_ATTR(temp1_input, S_IRUGO, show_local, NULL);
static DEVICE_ATTR(temp2_input, S_IRUGO, show_remote1, NULL);
static DEVICE_ATTR(temp3_input, S_IRUGO, show_remote2, NULL);
static DEVICE_ATTR(temp2_type, S_IWUSR | S_IRUGO, show_type1, set_type1);
static DEVICE_ATTR(temp3_type, S_IWUSR | S_IRUGO, show_type2, set_type2);
static DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_min1, set_min1);
static DEVICE_ATTR(temp3_min, S_IWUSR | S_IRUGO, show_min2, set_min2);
static DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_max1, set_max1);
static DEVICE_ATTR(temp3_max, S_IWUSR | S_IRUGO, show_max2, set_max2);
static DEVICE_ATTR(rate, S_IWUSR | S_IRUGO, show_rate, set_rate);
static struct attribute *lm95241_attributes[] = {
&dev_attr_temp1_input.attr,
&dev_attr_temp2_input.attr,
&dev_attr_temp3_input.attr,
&dev_attr_temp2_type.attr,
&dev_attr_temp3_type.attr,
&dev_attr_temp2_min.attr,
&dev_attr_temp3_min.attr,
&dev_attr_temp2_max.attr,
&dev_attr_temp3_max.attr,
&dev_attr_rate.attr,
NULL
};
static const struct attribute_group lm95241_group = {
.attrs = lm95241_attributes,
};
/* Return 0 if detection is successful, -ENODEV otherwise */
static int lm95241_detect(struct i2c_client *new_client, int kind,
struct i2c_board_info *info)
{
struct i2c_adapter *adapter = new_client->adapter;
int address = new_client->addr;
const char *name = "";
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
return -ENODEV;
/*
* Now we do the remaining detection. A negative kind means that
* the driver was loaded with no force parameter (default), so we
* must both detect and identify the chip. 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.
*/
if (kind < 0) { /* detection */
if ((i2c_smbus_read_byte_data(new_client, LM95241_REG_R_MAN_ID)
!= MANUFACTURER_ID)
|| (i2c_smbus_read_byte_data(new_client, LM95241_REG_R_CHIP_ID)
< DEFAULT_REVISION)) {
dev_dbg(&adapter->dev,
"LM95241 detection failed at 0x%02x.\n",
address);
return -ENODEV;
}
}
if (kind <= 0) { /* identification */
if ((i2c_smbus_read_byte_data(new_client, LM95241_REG_R_MAN_ID)
== MANUFACTURER_ID)
&& (i2c_smbus_read_byte_data(new_client, LM95241_REG_R_CHIP_ID)
>= DEFAULT_REVISION)) {
kind = lm95241;
if (kind <= 0) { /* identification failed */
dev_info(&adapter->dev, "Unsupported chip\n");
return -ENODEV;
}
}
}
/* Fill the i2c board info */
if (kind == lm95241)
name = "lm95241";
strlcpy(info->type, name, I2C_NAME_SIZE);
return 0;
}
static int lm95241_probe(struct i2c_client *new_client,
const struct i2c_device_id *id)
{
struct lm95241_data *data;
int err;
data = kzalloc(sizeof(struct lm95241_data), GFP_KERNEL);
if (!data) {
err = -ENOMEM;
goto exit;
}
i2c_set_clientdata(new_client, data);
mutex_init(&data->update_lock);
/* Initialize the LM95241 chip */
lm95241_init_client(new_client);
/* Register sysfs hooks */
err = sysfs_create_group(&new_client->dev.kobj, &lm95241_group);
if (err)
goto exit_free;
data->hwmon_dev = hwmon_device_register(&new_client->dev);
if (IS_ERR(data->hwmon_dev)) {
err = PTR_ERR(data->hwmon_dev);
goto exit_remove_files;
}
return 0;
exit_remove_files:
sysfs_remove_group(&new_client->dev.kobj, &lm95241_group);
exit_free:
kfree(data);
exit:
return err;
}
static void lm95241_init_client(struct i2c_client *client)
{
struct lm95241_data *data = i2c_get_clientdata(client);
data->rate = HZ; /* 1 sec default */
data->valid = 0;
data->config = CFG_CR0076;
data->model = 0;
data->trutherm = (TT_OFF << TT1_SHIFT) | (TT_OFF << TT2_SHIFT);
i2c_smbus_write_byte_data(client, LM95241_REG_RW_CONFIG,
data->config);
i2c_smbus_write_byte_data(client, LM95241_REG_RW_REM_FILTER,
R1FE_MASK | R2FE_MASK);
i2c_smbus_write_byte_data(client, LM95241_REG_RW_TRUTHERM,
data->trutherm);
i2c_smbus_write_byte_data(client, LM95241_REG_RW_REMOTE_MODEL,
data->model);
}
static int lm95241_remove(struct i2c_client *client)
{
struct lm95241_data *data = i2c_get_clientdata(client);
hwmon_device_unregister(data->hwmon_dev);
sysfs_remove_group(&client->dev.kobj, &lm95241_group);
i2c_set_clientdata(client, NULL);
kfree(data);
return 0;
}
static struct lm95241_data *lm95241_update_device(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct lm95241_data *data = i2c_get_clientdata(client);
mutex_lock(&data->update_lock);
if (time_after(jiffies, data->last_updated + data->rate) ||
!data->valid) {
dev_dbg(&client->dev, "Updating lm95241 data.\n");
data->local_h =
i2c_smbus_read_byte_data(client,
LM95241_REG_R_LOCAL_TEMPH);
data->local_l =
i2c_smbus_read_byte_data(client,
LM95241_REG_R_LOCAL_TEMPL);
data->remote1_h =
i2c_smbus_read_byte_data(client,
LM95241_REG_R_REMOTE1_TEMPH);
data->remote1_l =
i2c_smbus_read_byte_data(client,
LM95241_REG_R_REMOTE1_TEMPL);
data->remote2_h =
i2c_smbus_read_byte_data(client,
LM95241_REG_R_REMOTE2_TEMPH);
data->remote2_l =
i2c_smbus_read_byte_data(client,
LM95241_REG_R_REMOTE2_TEMPL);
data->last_updated = jiffies;
data->valid = 1;
}
mutex_unlock(&data->update_lock);
return data;
}
/* Driver data (common to all clients) */
static const struct i2c_device_id lm95241_id[] = {
{ "lm95241", lm95241 },
{ }
};
MODULE_DEVICE_TABLE(i2c, lm95241_id);
static struct i2c_driver lm95241_driver = {
.class = I2C_CLASS_HWMON,
.driver = {
.name = "lm95241",
},
.probe = lm95241_probe,
.remove = lm95241_remove,
.id_table = lm95241_id,
.detect = lm95241_detect,
.address_data = &addr_data,
};
static int __init sensors_lm95241_init(void)
{
return i2c_add_driver(&lm95241_driver);
}
static void __exit sensors_lm95241_exit(void)
{
i2c_del_driver(&lm95241_driver);
}
MODULE_AUTHOR("Davide Rizzo <elpa-rizzo@gmail.com>");
MODULE_DESCRIPTION("LM95241 sensor driver");
MODULE_LICENSE("GPL");
module_init(sensors_lm95241_init);
module_exit(sensors_lm95241_exit);
