/*
* Copyright (c) 2011 David George <david.george@ska.ac.za>
*
* based on adm1021.c
* some credit to Christoph Scheurer, but largely a rewrite
*
* 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>
/* Addresses to scan */
static unsigned short max1668_addr_list[] = {
0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END };
/* max1668 registers */
#define MAX1668_REG_TEMP(nr) (nr)
#define MAX1668_REG_STAT1 0x05
#define MAX1668_REG_STAT2 0x06
#define MAX1668_REG_MAN_ID 0xfe
#define MAX1668_REG_DEV_ID 0xff
/* limits */
/* write high limits */
#define MAX1668_REG_LIMH_WR(nr) (0x13 + 2 * (nr))
/* write low limits */
#define MAX1668_REG_LIML_WR(nr) (0x14 + 2 * (nr))
/* read high limits */
#define MAX1668_REG_LIMH_RD(nr) (0x08 + 2 * (nr))
/* read low limits */
#define MAX1668_REG_LIML_RD(nr) (0x09 + 2 * (nr))
/* manufacturer and device ID Constants */
#define MAN_ID_MAXIM 0x4d
#define DEV_ID_MAX1668 0x3
#define DEV_ID_MAX1805 0x5
#define DEV_ID_MAX1989 0xb
/* read only mode module parameter */
static bool read_only;
module_param(read_only, bool, 0);
MODULE_PARM_DESC(read_only, "Don't set any values, read only mode");
enum chips { max1668, max1805, max1989 };
struct max1668_data {
struct device *hwmon_dev;
enum chips type;
struct mutex update_lock;
char valid; /* !=0 if following fields are valid */
unsigned long last_updated; /* In jiffies */
/* 1x local and 4x remote */
s8 temp_max[5];
s8 temp_min[5];
s8 temp[5];
u16 alarms;
};
static struct max1668_data *max1668_update_device(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct max1668_data *data = i2c_get_clientdata(client);
struct max1668_data *ret = data;
s32 val;
int i;
mutex_lock(&data->update_lock);
if (data->valid && !time_after(jiffies,
data->last_updated + HZ + HZ / 2))
goto abort;
for (i = 0; i < 5; i++) {
val = i2c_smbus_read_byte_data(client, MAX1668_REG_TEMP(i));
if (unlikely(val < 0)) {
ret = ERR_PTR(val);
goto abort;
}
data->temp[i] = (s8) val;
val = i2c_smbus_read_byte_data(client, MAX1668_REG_LIMH_RD(i));
if (unlikely(val < 0)) {
ret = ERR_PTR(val);
goto abort;
}
data->temp_max[i] = (s8) val;
val = i2c_smbus_read_byte_data(client, MAX1668_REG_LIML_RD(i));
if (unlikely(val < 0)) {
ret = ERR_PTR(val);
goto abort;
}
data->temp_min[i] = (s8) val;
}
val = i2c_smbus_read_byte_data(client, MAX1668_REG_STAT1);
if (unlikely(val < 0)) {
ret = ERR_PTR(val);
goto abort;
}
data->alarms = val << 8;
val = i2c_smbus_read_byte_data(client, MAX1668_REG_STAT2);
if (unlikely(val < 0)) {
ret = ERR_PTR(val);
goto abort;
}
data->alarms |= val;
data->last_updated = jiffies;
data->valid = 1;
abort:
mutex_unlock(&data->update_lock);
return ret;
}
static ssize_t show_temp(struct device *dev,
struct device_attribute *devattr, char *buf)
{
int index = to_sensor_dev_attr(devattr)->index;
struct max1668_data *data = max1668_update_device(dev);
if (IS_ERR(data))
return PTR_ERR(data);
return sprintf(buf, "%d\n", data->temp[index] * 1000);
}
static ssize_t show_temp_max(struct device *dev,
struct device_attribute *devattr, char *buf)
{
int index = to_sensor_dev_attr(devattr)->index;
struct max1668_data *data = max1668_update_device(dev);
if (IS_ERR(data))
return PTR_ERR(data);
return sprintf(buf, "%d\n", data->temp_max[index] * 1000);
}
static ssize_t show_temp_min(struct device *dev,
struct device_attribute *devattr, char *buf)
{
int index = to_sensor_dev_attr(devattr)->index;
struct max1668_data *data = max1668_update_device(dev);
if (IS_ERR(data))
return PTR_ERR(data);
return sprintf(buf, "%d\n", data->temp_min[index] * 1000);
}
static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
char *buf)
{
int index = to_sensor_dev_attr(attr)->index;
struct max1668_data *data = max1668_update_device(dev);
if (IS_ERR(data))
return PTR_ERR(data);
return sprintf(buf, "%u\n", (data->alarms >> index) & 0x1);
}
static ssize_t show_fault(struct device *dev,
struct device_attribute *devattr, char *buf)
{
int index = to_sensor_dev_attr(devattr)->index;
struct max1668_data *data = max1668_update_device(dev);
if (IS_ERR(data))
return PTR_ERR(data);
return sprintf(buf, "%u\n",
(data->alarms & (1 << 12)) && data->temp[index] == 127);
}
static ssize_t set_temp_max(struct device *dev,
struct device_attribute *devattr,
const char *buf, size_t count)
{
int index = to_sensor_dev_attr(devattr)->index;
struct i2c_client *client = to_i2c_client(dev);
struct max1668_data *data = i2c_get_clientdata(client);
long temp;
int ret;
ret = kstrtol(buf, 10, &temp);
if (ret < 0)
return ret;
mutex_lock(&data->update_lock);
data->temp_max[index] = SENSORS_LIMIT(temp/1000, -128, 127);
if (i2c_smbus_write_byte_data(client,
MAX1668_REG_LIMH_WR(index),
data->temp_max[index]))
count = -EIO;
mutex_unlock(&data->update_lock);
return count;
}
static ssize_t set_temp_min(struct device *dev,
struct device_attribute *devattr,
const char *buf, size_t count)
{
int index = to_sensor_dev_attr(devattr)->index;
struct i2c_client *client = to_i2c_client(dev);
struct max1668_data *data = i2c_get_clientdata(client);
long temp;
int ret;
ret = kstrtol(buf, 10, &temp);
if (ret < 0)
return ret;
mutex_lock(&data->update_lock);
data->temp_min[index] = SENSORS_LIMIT(temp/1000, -128, 127);
if (i2c_smbus_write_byte_data(client,
MAX1668_REG_LIML_WR(index),
data->temp_max[index]))
count = -EIO;
mutex_unlock(&data->update_lock);
return count;
}
static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO, show_temp_max,
set_temp_max, 0);
static SENSOR_DEVICE_ATTR(temp1_min, S_IRUGO, show_temp_min,
set_temp_min, 0);
static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, 1);
static SENSOR_DEVICE_ATTR(temp2_max, S_IRUGO, show_temp_max,
set_temp_max, 1);
static SENSOR_DEVICE_ATTR(temp2_min, S_IRUGO, show_temp_min,
set_temp_min, 1);
static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp, NULL, 2);
static SENSOR_DEVICE_ATTR(temp3_max, S_IRUGO, show_temp_max,
set_temp_max, 2);
static SENSOR_DEVICE_ATTR(temp3_min, S_IRUGO, show_temp_min,
set_temp_min, 2);
static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp, NULL, 3);
static SENSOR_DEVICE_ATTR(temp4_max, S_IRUGO, show_temp_max,
set_temp_max, 3);
static SENSOR_DEVICE_ATTR(temp4_min, S_IRUGO, show_temp_min,
set_temp_min, 3);
static SENSOR_DEVICE_ATTR(temp5_input, S_IRUGO, show_temp, NULL, 4);
static SENSOR_DEVICE_ATTR(temp5_max, S_IRUGO, show_temp_max,
set_temp_max, 4);
static SENSOR_DEVICE_ATTR(temp5_min, S_IRUGO, show_temp_min,
set_temp_min, 4);
static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 14);
static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL, 13);
static SENSOR_DEVICE_ATTR(temp2_min_alarm, S_IRUGO, show_alarm, NULL, 7);
static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 6);
static SENSOR_DEVICE_ATTR(temp3_min_alarm, S_IRUGO, show_alarm, NULL, 5);
static SENSOR_DEVICE_ATTR(temp3_max_alarm, S_IRUGO, show_alarm, NULL, 4);
static SENSOR_DEVICE_ATTR(temp4_min_alarm, S_IRUGO, show_alarm, NULL, 3);
static SENSOR_DEVICE_ATTR(temp4_max_alarm, S_IRUGO, show_alarm, NULL, 2);
static SENSOR_DEVICE_ATTR(temp5_min_alarm, S_IRUGO, show_alarm, NULL, 1);
static SENSOR_DEVICE_ATTR(temp5_max_alarm, S_IRUGO, show_alarm, NULL, 0);
static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_fault, NULL, 1);
static SENSOR_DEVICE_ATTR(temp3_fault, S_IRUGO, show_fault, NULL, 2);
static SENSOR_DEVICE_ATTR(temp4_fault, S_IRUGO, show_fault, NULL, 3);
static SENSOR_DEVICE_ATTR(temp5_fault, S_IRUGO, show_fault, NULL, 4);
/* Attributes common to MAX1668, MAX1989 and MAX1805 */
static struct attribute *max1668_attribute_common[] = {
&sensor_dev_attr_temp1_max.dev_attr.attr,
&sensor_dev_attr_temp1_min.dev_attr.attr,
&sensor_dev_attr_temp1_input.dev_attr.attr,
&sensor_dev_attr_temp2_max.dev_attr.attr,
&sensor_dev_attr_temp2_min.dev_attr.attr,
&sensor_dev_attr_temp2_input.dev_attr.attr,
&sensor_dev_attr_temp3_max.dev_attr.attr,
&sensor_dev_attr_temp3_min.dev_attr.attr,
&sensor_dev_attr_temp3_input.dev_attr.attr,
&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
&sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
&sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
&sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
&sensor_dev_attr_temp3_max_alarm.dev_attr.attr,
&sensor_dev_attr_temp3_min_alarm.dev_attr.attr,
&sensor_dev_attr_temp2_fault.dev_attr.attr,
&sensor_dev_attr_temp3_fault.dev_attr.attr,
NULL
};
/* Attributes not present on MAX1805 */
static struct attribute *max1668_attribute_unique[] = {
&sensor_dev_attr_temp4_max.dev_attr.attr,
&sensor_dev_attr_temp4_min.dev_attr.attr,
&sensor_dev_attr_temp4_input.dev_attr.attr,
&sensor_dev_attr_temp5_max.dev_attr.attr,
&sensor_dev_attr_temp5_min.dev_attr.attr,
&sensor_dev_attr_temp5_input.dev_attr.attr,
&sensor_dev_attr_temp4_max_alarm.dev_attr.attr,
&sensor_dev_attr_temp4_min_alarm.dev_attr.attr,
&sensor_dev_attr_temp5_max_alarm.dev_attr.attr,
&sensor_dev_attr_temp5_min_alarm.dev_attr.attr,
&sensor_dev_attr_temp4_fault.dev_attr.attr,
&sensor_dev_attr_temp5_fault.dev_attr.attr,
NULL
};
static umode_t max1668_attribute_mode(struct kobject *kobj,
struct attribute *attr, int index)
{
umode_t ret = S_IRUGO;
if (read_only)
return ret;
if (attr == &sensor_dev_attr_temp1_max.dev_attr.attr ||
attr == &sensor_dev_attr_temp2_max.dev_attr.attr ||
attr == &sensor_dev_attr_temp3_max.dev_attr.attr ||
attr == &sensor_dev_attr_temp4_max.dev_attr.attr ||
attr == &sensor_dev_attr_temp5_max.dev_attr.attr ||
attr == &sensor_dev_attr_temp1_min.dev_attr.attr ||
attr == &sensor_dev_attr_temp2_min.dev_attr.attr ||
attr == &sensor_dev_attr_temp3_min.dev_attr.attr ||
attr == &sensor_dev_attr_temp4_min.dev_attr.attr ||
attr == &sensor_dev_attr_temp5_min.dev_attr.attr)
ret |= S_IWUSR;
return ret;
}
static const struct attribute_group max1668_group_common = {
.attrs = max1668_attribute_common,
.is_visible = max1668_attribute_mode
};
static const struct attribute_group max1668_group_unique = {
.attrs = max1668_attribute_unique,
.is_visible = max1668_attribute_mode
};
/* Return 0 if detection is successful, -ENODEV otherwise */
static int max1668_detect(struct i2c_client *client,
struct i2c_board_info *info)
{
struct i2c_adapter *adapter = client->adapter;
const char *type_name;
int man_id, dev_id;
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
return -ENODEV;
/* Check for unsupported part */
man_id = i2c_smbus_read_byte_data(client, MAX1668_REG_MAN_ID);
if (man_id != MAN_ID_MAXIM)
return -ENODEV;
dev_id = i2c_smbus_read_byte_data(client, MAX1668_REG_DEV_ID);
if (dev_id < 0)
return -ENODEV;
type_name = NULL;
if (dev_id == DEV_ID_MAX1668)
type_name = "max1668";
else if (dev_id == DEV_ID_MAX1805)
type_name = "max1805";
else if (dev_id == DEV_ID_MAX1989)
type_name = "max1989";
if (!type_name)
return -ENODEV;
strlcpy(info->type, type_name, I2C_NAME_SIZE);
return 0;
}
static int max1668_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct i2c_adapter *adapter = client->adapter;
struct max1668_data *data;
int err;
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
return -ENODEV;
data = devm_kzalloc(&client->dev, sizeof(struct max1668_data),
GFP_KERNEL);
if (!data)
return -ENOMEM;
i2c_set_clientdata(client, data);
data->type = id->driver_data;
mutex_init(&data->update_lock);
/* Register sysfs hooks */
err = sysfs_create_group(&client->dev.kobj, &max1668_group_common);
if (err)
return err;
if (data->type == max1668 || data->type == max1989) {
err = sysfs_create_group(&client->dev.kobj,
&max1668_group_unique);
if (err)
goto error_sysrem0;
}
data->hwmon_dev = hwmon_device_register(&client->dev);
if (IS_ERR(data->hwmon_dev)) {
err = PTR_ERR(data->hwmon_dev);
goto error_sysrem1;
}
return 0;
error_sysrem1:
if (data->type == max1668 || data->type == max1989)
sysfs_remove_group(&client->dev.kobj, &max1668_group_unique);
error_sysrem0:
sysfs_remove_group(&client->dev.kobj, &max1668_group_common);
return err;
}
static int max1668_remove(struct i2c_client *client)
{
struct max1668_data *data = i2c_get_clientdata(client);
hwmon_device_unregister(data->hwmon_dev);
if (data->type == max1668 || data->type == max1989)
sysfs_remove_group(&client->dev.kobj, &max1668_group_unique);
sysfs_remove_group(&client->dev.kobj, &max1668_group_common);
return 0;
}
static const struct i2c_device_id max1668_id[] = {
{ "max1668", max1668 },
{ "max1805", max1805 },
{ "max1989", max1989 },
{ }
};
MODULE_DEVICE_TABLE(i2c, max1668_id);
/* This is the driver that will be inserted */
static struct i2c_driver max1668_driver = {
.class = I2C_CLASS_HWMON,
.driver = {
.name = "max1668",
},
.probe = max1668_probe,
.remove = max1668_remove,
.id_table = max1668_id,
.detect = max1668_detect,
.address_list = max1668_addr_list,
};
module_i2c_driver(max1668_driver);
MODULE_AUTHOR("David George <david.george@ska.ac.za>");
MODULE_DESCRIPTION("MAX1668 remote temperature sensor driver");
MODULE_LICENSE("GPL");
