- 根目录:
- drivers
- hwmon
- lm95245.c
/*
* Copyright (C) 2011 Alexander Stein <alexander.stein@systec-electronic.com>
*
* The LM95245 is a sensor chip made by TI / National Semiconductor.
* It reports up to two temperatures (its own plus an external one).
*
* This driver is based on lm95241.c
*
* 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[] = {
0x18, 0x19, 0x29, 0x4c, 0x4d, I2C_CLIENT_END };
/* LM95245 registers */
/* general registers */
#define LM95245_REG_RW_CONFIG1 0x03
#define LM95245_REG_RW_CONVERS_RATE 0x04
#define LM95245_REG_W_ONE_SHOT 0x0F
/* diode configuration */
#define LM95245_REG_RW_CONFIG2 0xBF
#define LM95245_REG_RW_REMOTE_OFFH 0x11
#define LM95245_REG_RW_REMOTE_OFFL 0x12
/* status registers */
#define LM95245_REG_R_STATUS1 0x02
#define LM95245_REG_R_STATUS2 0x33
/* limit registers */
#define LM95245_REG_RW_REMOTE_OS_LIMIT 0x07
#define LM95245_REG_RW_LOCAL_OS_TCRIT_LIMIT 0x20
#define LM95245_REG_RW_REMOTE_TCRIT_LIMIT 0x19
#define LM95245_REG_RW_COMMON_HYSTERESIS 0x21
/* temperature signed */
#define LM95245_REG_R_LOCAL_TEMPH_S 0x00
#define LM95245_REG_R_LOCAL_TEMPL_S 0x30
#define LM95245_REG_R_REMOTE_TEMPH_S 0x01
#define LM95245_REG_R_REMOTE_TEMPL_S 0x10
/* temperature unsigned */
#define LM95245_REG_R_REMOTE_TEMPH_U 0x31
#define LM95245_REG_R_REMOTE_TEMPL_U 0x32
/* id registers */
#define LM95245_REG_R_MAN_ID 0xFE
#define LM95245_REG_R_CHIP_ID 0xFF
/* LM95245 specific bitfields */
#define CFG_STOP 0x40
#define CFG_REMOTE_TCRIT_MASK 0x10
#define CFG_REMOTE_OS_MASK 0x08
#define CFG_LOCAL_TCRIT_MASK 0x04
#define CFG_LOCAL_OS_MASK 0x02
#define CFG2_OS_A0 0x40
#define CFG2_DIODE_FAULT_OS 0x20
#define CFG2_DIODE_FAULT_TCRIT 0x10
#define CFG2_REMOTE_TT 0x08
#define CFG2_REMOTE_FILTER_DIS 0x00
#define CFG2_REMOTE_FILTER_EN 0x06
/* conversation rate in ms */
#define RATE_CR0063 0x00
#define RATE_CR0364 0x01
#define RATE_CR1000 0x02
#define RATE_CR2500 0x03
#define STATUS1_DIODE_FAULT 0x04
#define STATUS1_RTCRIT 0x02
#define STATUS1_LOC 0x01
#define MANUFACTURER_ID 0x01
#define LM95235_REVISION 0xB1
#define LM95245_REVISION 0xB3
static const u8 lm95245_reg_address[] = {
LM95245_REG_R_LOCAL_TEMPH_S,
LM95245_REG_R_LOCAL_TEMPL_S,
LM95245_REG_R_REMOTE_TEMPH_S,
LM95245_REG_R_REMOTE_TEMPL_S,
LM95245_REG_R_REMOTE_TEMPH_U,
LM95245_REG_R_REMOTE_TEMPL_U,
LM95245_REG_RW_LOCAL_OS_TCRIT_LIMIT,
LM95245_REG_RW_REMOTE_TCRIT_LIMIT,
LM95245_REG_RW_COMMON_HYSTERESIS,
LM95245_REG_R_STATUS1,
};
/* Client data (each client gets its own) */
struct lm95245_data {
struct i2c_client *client;
struct mutex update_lock;
unsigned long last_updated; /* in jiffies */
unsigned long interval; /* in msecs */
bool valid; /* zero until following fields are valid */
/* registers values */
u8 regs[ARRAY_SIZE(lm95245_reg_address)];
u8 config1, config2;
};
/* Conversions */
static int temp_from_reg_unsigned(u8 val_h, u8 val_l)
{
return val_h * 1000 + val_l * 1000 / 256;
}
static int temp_from_reg_signed(u8 val_h, u8 val_l)
{
if (val_h & 0x80)
return (val_h - 0x100) * 1000;
return temp_from_reg_unsigned(val_h, val_l);
}
static struct lm95245_data *lm95245_update_device(struct device *dev)
{
struct lm95245_data *data = dev_get_drvdata(dev);
struct i2c_client *client = data->client;
mutex_lock(&data->update_lock);
if (time_after(jiffies, data->last_updated
+ msecs_to_jiffies(data->interval)) || !data->valid) {
int i;
for (i = 0; i < ARRAY_SIZE(lm95245_reg_address); i++)
data->regs[i]
= i2c_smbus_read_byte_data(client,
lm95245_reg_address[i]);
data->last_updated = jiffies;
data->valid = 1;
}
mutex_unlock(&data->update_lock);
return data;
}
static unsigned long lm95245_read_conversion_rate(struct i2c_client *client)
{
int rate;
unsigned long interval;
rate = i2c_smbus_read_byte_data(client, LM95245_REG_RW_CONVERS_RATE);
switch (rate) {
case RATE_CR0063:
interval = 63;
break;
case RATE_CR0364:
interval = 364;
break;
case RATE_CR1000:
interval = 1000;
break;
case RATE_CR2500:
default:
interval = 2500;
break;
}
return interval;
}
static unsigned long lm95245_set_conversion_rate(struct i2c_client *client,
unsigned long interval)
{
int rate;
if (interval <= 63) {
interval = 63;
rate = RATE_CR0063;
} else if (interval <= 364) {
interval = 364;
rate = RATE_CR0364;
} else if (interval <= 1000) {
interval = 1000;
rate = RATE_CR1000;
} else {
interval = 2500;
rate = RATE_CR2500;
}
i2c_smbus_write_byte_data(client, LM95245_REG_RW_CONVERS_RATE, rate);
return interval;
}
/* Sysfs stuff */
static ssize_t show_input(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct lm95245_data *data = lm95245_update_device(dev);
int temp;
int index = to_sensor_dev_attr(attr)->index;
/*
* Index 0 (Local temp) is always signed
* Index 2 (Remote temp) has both signed and unsigned data
* use signed calculation for remote if signed bit is set
*/
if (index == 0 || data->regs[index] & 0x80)
temp = temp_from_reg_signed(data->regs[index],
data->regs[index + 1]);
else
temp = temp_from_reg_unsigned(data->regs[index + 2],
data->regs[index + 3]);
return snprintf(buf, PAGE_SIZE - 1, "%d\n", temp);
}
static ssize_t show_limit(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct lm95245_data *data = lm95245_update_device(dev);
int index = to_sensor_dev_attr(attr)->index;
return snprintf(buf, PAGE_SIZE - 1, "%d\n",
data->regs[index] * 1000);
}
static ssize_t set_limit(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct lm95245_data *data = dev_get_drvdata(dev);
int index = to_sensor_dev_attr(attr)->index;
struct i2c_client *client = data->client;
unsigned long val;
if (kstrtoul(buf, 10, &val) < 0)
return -EINVAL;
val /= 1000;
val = clamp_val(val, 0, (index == 6 ? 127 : 255));
mutex_lock(&data->update_lock);
data->valid = 0;
i2c_smbus_write_byte_data(client, lm95245_reg_address[index], val);
mutex_unlock(&data->update_lock);
return count;
}
static ssize_t show_crit_hyst(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct lm95245_data *data = lm95245_update_device(dev);
int index = to_sensor_dev_attr(attr)->index;
int hyst = data->regs[index] - data->regs[8];
return snprintf(buf, PAGE_SIZE - 1, "%d\n", hyst * 1000);
}
static ssize_t set_crit_hyst(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct lm95245_data *data = dev_get_drvdata(dev);
int index = to_sensor_dev_attr(attr)->index;
struct i2c_client *client = data->client;
unsigned long val;
int hyst, limit;
if (kstrtoul(buf, 10, &val) < 0)
return -EINVAL;
mutex_lock(&data->update_lock);
limit = i2c_smbus_read_byte_data(client, lm95245_reg_address[index]);
hyst = limit - val / 1000;
hyst = clamp_val(hyst, 0, 31);
data->regs[8] = hyst;
/* shared crit hysteresis */
i2c_smbus_write_byte_data(client, LM95245_REG_RW_COMMON_HYSTERESIS,
hyst);
mutex_unlock(&data->update_lock);
return count;
}
static ssize_t show_type(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct lm95245_data *data = dev_get_drvdata(dev);
return snprintf(buf, PAGE_SIZE - 1,
data->config2 & CFG2_REMOTE_TT ? "1\n" : "2\n");
}
static ssize_t set_type(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct lm95245_data *data = dev_get_drvdata(dev);
struct i2c_client *client = data->client;
unsigned long val;
if (kstrtoul(buf, 10, &val) < 0)
return -EINVAL;
if (val != 1 && val != 2)
return -EINVAL;
mutex_lock(&data->update_lock);
if (val == 1)
data->config2 |= CFG2_REMOTE_TT;
else
data->config2 &= ~CFG2_REMOTE_TT;
data->valid = 0;
i2c_smbus_write_byte_data(client, LM95245_REG_RW_CONFIG2,
data->config2);
mutex_unlock(&data->update_lock);
return count;
}
static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct lm95245_data *data = lm95245_update_device(dev);
int index = to_sensor_dev_attr(attr)->index;
return snprintf(buf, PAGE_SIZE - 1, "%d\n",
!!(data->regs[9] & index));
}
static ssize_t show_interval(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct lm95245_data *data = lm95245_update_device(dev);
return snprintf(buf, PAGE_SIZE - 1, "%lu\n", data->interval);
}
static ssize_t set_interval(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct lm95245_data *data = dev_get_drvdata(dev);
struct i2c_client *client = data->client;
unsigned long val;
if (kstrtoul(buf, 10, &val) < 0)
return -EINVAL;
mutex_lock(&data->update_lock);
data->interval = lm95245_set_conversion_rate(client, val);
mutex_unlock(&data->update_lock);
return count;
}
static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_input, NULL, 0);
static SENSOR_DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO, show_limit,
set_limit, 6);
static SENSOR_DEVICE_ATTR(temp1_crit_hyst, S_IWUSR | S_IRUGO, show_crit_hyst,
set_crit_hyst, 6);
static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL,
STATUS1_LOC);
static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_input, NULL, 2);
static SENSOR_DEVICE_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_limit,
set_limit, 7);
static SENSOR_DEVICE_ATTR(temp2_crit_hyst, S_IRUGO, show_crit_hyst, NULL, 7);
static SENSOR_DEVICE_ATTR(temp2_crit_alarm, S_IRUGO, show_alarm, NULL,
STATUS1_RTCRIT);
static SENSOR_DEVICE_ATTR(temp2_type, S_IWUSR | S_IRUGO, show_type,
set_type, 0);
static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_alarm, NULL,
STATUS1_DIODE_FAULT);
static DEVICE_ATTR(update_interval, S_IWUSR | S_IRUGO, show_interval,
set_interval);
static struct attribute *lm95245_attrs[] = {
&sensor_dev_attr_temp1_input.dev_attr.attr,
&sensor_dev_attr_temp1_crit.dev_attr.attr,
&sensor_dev_attr_temp1_crit_hyst.dev_attr.attr,
&sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
&sensor_dev_attr_temp2_input.dev_attr.attr,
&sensor_dev_attr_temp2_crit.dev_attr.attr,
&sensor_dev_attr_temp2_crit_hyst.dev_attr.attr,
&sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
&sensor_dev_attr_temp2_type.dev_attr.attr,
&sensor_dev_attr_temp2_fault.dev_attr.attr,
&dev_attr_update_interval.attr,
NULL
};
ATTRIBUTE_GROUPS(lm95245);
/* Return 0 if detection is successful, -ENODEV otherwise */
static int lm95245_detect(struct i2c_client *new_client,
struct i2c_board_info *info)
{
struct i2c_adapter *adapter = new_client->adapter;
int address = new_client->addr;
const char *name;
int rev, id;
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
return -ENODEV;
id = i2c_smbus_read_byte_data(new_client, LM95245_REG_R_MAN_ID);
if (id != MANUFACTURER_ID)
return -ENODEV;
rev = i2c_smbus_read_byte_data(new_client, LM95245_REG_R_CHIP_ID);
switch (rev) {
case LM95235_REVISION:
if (address != 0x18 && address != 0x29 && address != 0x4c)
return -ENODEV;
name = "lm95235";
break;
case LM95245_REVISION:
name = "lm95245";
break;
default:
return -ENODEV;
}
strlcpy(info->type, name, I2C_NAME_SIZE);
return 0;
}
static void lm95245_init_client(struct i2c_client *client,
struct lm95245_data *data)
{
data->interval = lm95245_read_conversion_rate(client);
data->config1 = i2c_smbus_read_byte_data(client,
LM95245_REG_RW_CONFIG1);
data->config2 = i2c_smbus_read_byte_data(client,
LM95245_REG_RW_CONFIG2);
if (data->config1 & CFG_STOP) {
/* Clear the standby bit */
data->config1 &= ~CFG_STOP;
i2c_smbus_write_byte_data(client, LM95245_REG_RW_CONFIG1,
data->config1);
}
}
static int lm95245_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct device *dev = &client->dev;
struct lm95245_data *data;
struct device *hwmon_dev;
data = devm_kzalloc(dev, sizeof(struct lm95245_data), GFP_KERNEL);
if (!data)
return -ENOMEM;
data->client = client;
mutex_init(&data->update_lock);
/* Initialize the LM95245 chip */
lm95245_init_client(client, data);
hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
data,
lm95245_groups);
return PTR_ERR_OR_ZERO(hwmon_dev);
}
/* Driver data (common to all clients) */
static const struct i2c_device_id lm95245_id[] = {
{ "lm95235", 0 },
{ "lm95245", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, lm95245_id);
static struct i2c_driver lm95245_driver = {
.class = I2C_CLASS_HWMON,
.driver = {
.name = "lm95245",
},
.probe = lm95245_probe,
.id_table = lm95245_id,
.detect = lm95245_detect,
.address_list = normal_i2c,
};
module_i2c_driver(lm95245_driver);
MODULE_AUTHOR("Alexander Stein <alexander.stein@systec-electronic.com>");
MODULE_DESCRIPTION("LM95235/LM95245 sensor driver");
MODULE_LICENSE("GPL");