/*
* max6639.c - Support for Maxim MAX6639
*
* 2-Channel Temperature Monitor with Dual PWM Fan-Speed Controller
*
* Copyright (C) 2010, 2011 Roland Stigge <stigge@antcom.de>
*
* based on the initial MAX6639 support from semptian.net
* by He Changqing <hechangqing@semptian.com>
*
* 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/i2c/max6639.h>
/* Addresses to scan */
static unsigned short normal_i2c[] = { 0x2c, 0x2e, 0x2f, I2C_CLIENT_END };
/* The MAX6639 registers, valid channel numbers: 0, 1 */
#define MAX6639_REG_TEMP(ch) (0x00 + (ch))
#define MAX6639_REG_STATUS 0x02
#define MAX6639_REG_OUTPUT_MASK 0x03
#define MAX6639_REG_GCONFIG 0x04
#define MAX6639_REG_TEMP_EXT(ch) (0x05 + (ch))
#define MAX6639_REG_ALERT_LIMIT(ch) (0x08 + (ch))
#define MAX6639_REG_OT_LIMIT(ch) (0x0A + (ch))
#define MAX6639_REG_THERM_LIMIT(ch) (0x0C + (ch))
#define MAX6639_REG_FAN_CONFIG1(ch) (0x10 + (ch) * 4)
#define MAX6639_REG_FAN_CONFIG2a(ch) (0x11 + (ch) * 4)
#define MAX6639_REG_FAN_CONFIG2b(ch) (0x12 + (ch) * 4)
#define MAX6639_REG_FAN_CONFIG3(ch) (0x13 + (ch) * 4)
#define MAX6639_REG_FAN_CNT(ch) (0x20 + (ch))
#define MAX6639_REG_TARGET_CNT(ch) (0x22 + (ch))
#define MAX6639_REG_FAN_PPR(ch) (0x24 + (ch))
#define MAX6639_REG_TARGTDUTY(ch) (0x26 + (ch))
#define MAX6639_REG_FAN_START_TEMP(ch) (0x28 + (ch))
#define MAX6639_REG_DEVID 0x3D
#define MAX6639_REG_MANUID 0x3E
#define MAX6639_REG_DEVREV 0x3F
/* Register bits */
#define MAX6639_GCONFIG_STANDBY 0x80
#define MAX6639_GCONFIG_POR 0x40
#define MAX6639_GCONFIG_DISABLE_TIMEOUT 0x20
#define MAX6639_GCONFIG_CH2_LOCAL 0x10
#define MAX6639_GCONFIG_PWM_FREQ_HI 0x08
#define MAX6639_FAN_CONFIG1_PWM 0x80
#define MAX6639_FAN_CONFIG3_THERM_FULL_SPEED 0x40
static const int rpm_ranges[] = { 2000, 4000, 8000, 16000 };
#define FAN_FROM_REG(val, rpm_range) ((val) == 0 || (val) == 255 ? \
0 : (rpm_ranges[rpm_range] * 30) / (val))
#define TEMP_LIMIT_TO_REG(val) clamp_val((val) / 1000, 0, 255)
/*
* Client data (each client gets its own)
*/
struct max6639_data {
struct device *hwmon_dev;
struct mutex update_lock;
char valid; /* !=0 if following fields are valid */
unsigned long last_updated; /* In jiffies */
/* Register values sampled regularly */
u16 temp[2]; /* Temperature, in 1/8 C, 0..255 C */
bool temp_fault[2]; /* Detected temperature diode failure */
u8 fan[2]; /* Register value: TACH count for fans >=30 */
u8 status; /* Detected channel alarms and fan failures */
/* Register values only written to */
u8 pwm[2]; /* Register value: Duty cycle 0..120 */
u8 temp_therm[2]; /* THERM Temperature, 0..255 C (->_max) */
u8 temp_alert[2]; /* ALERT Temperature, 0..255 C (->_crit) */
u8 temp_ot[2]; /* OT Temperature, 0..255 C (->_emergency) */
/* Register values initialized only once */
u8 ppr; /* Pulses per rotation 0..3 for 1..4 ppr */
u8 rpm_range; /* Index in above rpm_ranges table */
};
static struct max6639_data *max6639_update_device(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct max6639_data *data = i2c_get_clientdata(client);
struct max6639_data *ret = data;
int i;
int status_reg;
mutex_lock(&data->update_lock);
if (time_after(jiffies, data->last_updated + 2 * HZ) || !data->valid) {
int res;
dev_dbg(&client->dev, "Starting max6639 update\n");
status_reg = i2c_smbus_read_byte_data(client,
MAX6639_REG_STATUS);
if (status_reg < 0) {
ret = ERR_PTR(status_reg);
goto abort;
}
data->status = status_reg;
for (i = 0; i < 2; i++) {
res = i2c_smbus_read_byte_data(client,
MAX6639_REG_FAN_CNT(i));
if (res < 0) {
ret = ERR_PTR(res);
goto abort;
}
data->fan[i] = res;
res = i2c_smbus_read_byte_data(client,
MAX6639_REG_TEMP_EXT(i));
if (res < 0) {
ret = ERR_PTR(res);
goto abort;
}
data->temp[i] = res >> 5;
data->temp_fault[i] = res & 0x01;
res = i2c_smbus_read_byte_data(client,
MAX6639_REG_TEMP(i));
if (res < 0) {
ret = ERR_PTR(res);
goto abort;
}
data->temp[i] |= res << 3;
}
data->last_updated = jiffies;
data->valid = 1;
}
abort:
mutex_unlock(&data->update_lock);
return ret;
}
static ssize_t show_temp_input(struct device *dev,
struct device_attribute *dev_attr, char *buf)
{
long temp;
struct max6639_data *data = max6639_update_device(dev);
struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
if (IS_ERR(data))
return PTR_ERR(data);
temp = data->temp[attr->index] * 125;
return sprintf(buf, "%ld\n", temp);
}
static ssize_t show_temp_fault(struct device *dev,
struct device_attribute *dev_attr, char *buf)
{
struct max6639_data *data = max6639_update_device(dev);
struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
if (IS_ERR(data))
return PTR_ERR(data);
return sprintf(buf, "%d\n", data->temp_fault[attr->index]);
}
static ssize_t show_temp_max(struct device *dev,
struct device_attribute *dev_attr, char *buf)
{
struct i2c_client *client = to_i2c_client(dev);
struct max6639_data *data = i2c_get_clientdata(client);
struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
return sprintf(buf, "%d\n", (data->temp_therm[attr->index] * 1000));
}
static ssize_t set_temp_max(struct device *dev,
struct device_attribute *dev_attr,
const char *buf, size_t count)
{
struct i2c_client *client = to_i2c_client(dev);
struct max6639_data *data = i2c_get_clientdata(client);
struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
unsigned long val;
int res;
res = kstrtoul(buf, 10, &val);
if (res)
return res;
mutex_lock(&data->update_lock);
data->temp_therm[attr->index] = TEMP_LIMIT_TO_REG(val);
i2c_smbus_write_byte_data(client,
MAX6639_REG_THERM_LIMIT(attr->index),
data->temp_therm[attr->index]);
mutex_unlock(&data->update_lock);
return count;
}
static ssize_t show_temp_crit(struct device *dev,
struct device_attribute *dev_attr, char *buf)
{
struct i2c_client *client = to_i2c_client(dev);
struct max6639_data *data = i2c_get_clientdata(client);
struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
return sprintf(buf, "%d\n", (data->temp_alert[attr->index] * 1000));
}
static ssize_t set_temp_crit(struct device *dev,
struct device_attribute *dev_attr,
const char *buf, size_t count)
{
struct i2c_client *client = to_i2c_client(dev);
struct max6639_data *data = i2c_get_clientdata(client);
struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
unsigned long val;
int res;
res = kstrtoul(buf, 10, &val);
if (res)
return res;
mutex_lock(&data->update_lock);
data->temp_alert[attr->index] = TEMP_LIMIT_TO_REG(val);
i2c_smbus_write_byte_data(client,
MAX6639_REG_ALERT_LIMIT(attr->index),
data->temp_alert[attr->index]);
mutex_unlock(&data->update_lock);
return count;
}
static ssize_t show_temp_emergency(struct device *dev,
struct device_attribute *dev_attr,
char *buf)
{
struct i2c_client *client = to_i2c_client(dev);
struct max6639_data *data = i2c_get_clientdata(client);
struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
return sprintf(buf, "%d\n", (data->temp_ot[attr->index] * 1000));
}
static ssize_t set_temp_emergency(struct device *dev,
struct device_attribute *dev_attr,
const char *buf, size_t count)
{
struct i2c_client *client = to_i2c_client(dev);
struct max6639_data *data = i2c_get_clientdata(client);
struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
unsigned long val;
int res;
res = kstrtoul(buf, 10, &val);
if (res)
return res;
mutex_lock(&data->update_lock);
data->temp_ot[attr->index] = TEMP_LIMIT_TO_REG(val);
i2c_smbus_write_byte_data(client,
MAX6639_REG_OT_LIMIT(attr->index),
data->temp_ot[attr->index]);
mutex_unlock(&data->update_lock);
return count;
}
static ssize_t show_pwm(struct device *dev,
struct device_attribute *dev_attr, char *buf)
{
struct i2c_client *client = to_i2c_client(dev);
struct max6639_data *data = i2c_get_clientdata(client);
struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
return sprintf(buf, "%d\n", data->pwm[attr->index] * 255 / 120);
}
static ssize_t set_pwm(struct device *dev,
struct device_attribute *dev_attr,
const char *buf, size_t count)
{
struct i2c_client *client = to_i2c_client(dev);
struct max6639_data *data = i2c_get_clientdata(client);
struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
unsigned long val;
int res;
res = kstrtoul(buf, 10, &val);
if (res)
return res;
val = clamp_val(val, 0, 255);
mutex_lock(&data->update_lock);
data->pwm[attr->index] = (u8)(val * 120 / 255);
i2c_smbus_write_byte_data(client,
MAX6639_REG_TARGTDUTY(attr->index),
data->pwm[attr->index]);
mutex_unlock(&data->update_lock);
return count;
}
static ssize_t show_fan_input(struct device *dev,
struct device_attribute *dev_attr, char *buf)
{
struct max6639_data *data = max6639_update_device(dev);
struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
if (IS_ERR(data))
return PTR_ERR(data);
return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan[attr->index],
data->rpm_range));
}
static ssize_t show_alarm(struct device *dev,
struct device_attribute *dev_attr, char *buf)
{
struct max6639_data *data = max6639_update_device(dev);
struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
if (IS_ERR(data))
return PTR_ERR(data);
return sprintf(buf, "%d\n", !!(data->status & (1 << attr->index)));
}
static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_input, NULL, 0);
static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp_input, NULL, 1);
static SENSOR_DEVICE_ATTR(temp1_fault, S_IRUGO, show_temp_fault, NULL, 0);
static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_temp_fault, NULL, 1);
static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp_max,
set_temp_max, 0);
static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp_max,
set_temp_max, 1);
static SENSOR_DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO, show_temp_crit,
set_temp_crit, 0);
static SENSOR_DEVICE_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_temp_crit,
set_temp_crit, 1);
static SENSOR_DEVICE_ATTR(temp1_emergency, S_IWUSR | S_IRUGO,
show_temp_emergency, set_temp_emergency, 0);
static SENSOR_DEVICE_ATTR(temp2_emergency, S_IWUSR | S_IRUGO,
show_temp_emergency, set_temp_emergency, 1);
static SENSOR_DEVICE_ATTR(pwm1, S_IWUSR | S_IRUGO, show_pwm, set_pwm, 0);
static SENSOR_DEVICE_ATTR(pwm2, S_IWUSR | S_IRUGO, show_pwm, set_pwm, 1);
static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, show_fan_input, NULL, 0);
static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, show_fan_input, NULL, 1);
static SENSOR_DEVICE_ATTR(fan1_fault, S_IRUGO, show_alarm, NULL, 1);
static SENSOR_DEVICE_ATTR(fan2_fault, S_IRUGO, show_alarm, NULL, 0);
static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 3);
static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 2);
static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL, 7);
static SENSOR_DEVICE_ATTR(temp2_crit_alarm, S_IRUGO, show_alarm, NULL, 6);
static SENSOR_DEVICE_ATTR(temp1_emergency_alarm, S_IRUGO, show_alarm, NULL, 5);
static SENSOR_DEVICE_ATTR(temp2_emergency_alarm, S_IRUGO, show_alarm, NULL, 4);
static struct attribute *max6639_attributes[] = {
&sensor_dev_attr_temp1_input.dev_attr.attr,
&sensor_dev_attr_temp2_input.dev_attr.attr,
&sensor_dev_attr_temp1_fault.dev_attr.attr,
&sensor_dev_attr_temp2_fault.dev_attr.attr,
&sensor_dev_attr_temp1_max.dev_attr.attr,
&sensor_dev_attr_temp2_max.dev_attr.attr,
&sensor_dev_attr_temp1_crit.dev_attr.attr,
&sensor_dev_attr_temp2_crit.dev_attr.attr,
&sensor_dev_attr_temp1_emergency.dev_attr.attr,
&sensor_dev_attr_temp2_emergency.dev_attr.attr,
&sensor_dev_attr_pwm1.dev_attr.attr,
&sensor_dev_attr_pwm2.dev_attr.attr,
&sensor_dev_attr_fan1_input.dev_attr.attr,
&sensor_dev_attr_fan2_input.dev_attr.attr,
&sensor_dev_attr_fan1_fault.dev_attr.attr,
&sensor_dev_attr_fan2_fault.dev_attr.attr,
&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
&sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
&sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
&sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
&sensor_dev_attr_temp1_emergency_alarm.dev_attr.attr,
&sensor_dev_attr_temp2_emergency_alarm.dev_attr.attr,
NULL
};
static const struct attribute_group max6639_group = {
.attrs = max6639_attributes,
};
/*
* returns respective index in rpm_ranges table
* 1 by default on invalid range
*/
static int rpm_range_to_reg(int range)
{
int i;
for (i = 0; i < ARRAY_SIZE(rpm_ranges); i++) {
if (rpm_ranges[i] == range)
return i;
}
return 1; /* default: 4000 RPM */
}
static int max6639_init_client(struct i2c_client *client)
{
struct max6639_data *data = i2c_get_clientdata(client);
struct max6639_platform_data *max6639_info =
client->dev.platform_data;
int i;
int rpm_range = 1; /* default: 4000 RPM */
int err;
/* Reset chip to default values, see below for GCONFIG setup */
err = i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG,
MAX6639_GCONFIG_POR);
if (err)
goto exit;
/* Fans pulse per revolution is 2 by default */
if (max6639_info && max6639_info->ppr > 0 &&
max6639_info->ppr < 5)
data->ppr = max6639_info->ppr;
else
data->ppr = 2;
data->ppr -= 1;
if (max6639_info)
rpm_range = rpm_range_to_reg(max6639_info->rpm_range);
data->rpm_range = rpm_range;
for (i = 0; i < 2; i++) {
/* Set Fan pulse per revolution */
err = i2c_smbus_write_byte_data(client,
MAX6639_REG_FAN_PPR(i),
data->ppr << 6);
if (err)
goto exit;
/* Fans config PWM, RPM */
err = i2c_smbus_write_byte_data(client,
MAX6639_REG_FAN_CONFIG1(i),
MAX6639_FAN_CONFIG1_PWM | rpm_range);
if (err)
goto exit;
/* Fans PWM polarity high by default */
if (max6639_info && max6639_info->pwm_polarity == 0)
err = i2c_smbus_write_byte_data(client,
MAX6639_REG_FAN_CONFIG2a(i), 0x00);
else
err = i2c_smbus_write_byte_data(client,
MAX6639_REG_FAN_CONFIG2a(i), 0x02);
if (err)
goto exit;
/*
* /THERM full speed enable,
* PWM frequency 25kHz, see also GCONFIG below
*/
err = i2c_smbus_write_byte_data(client,
MAX6639_REG_FAN_CONFIG3(i),
MAX6639_FAN_CONFIG3_THERM_FULL_SPEED | 0x03);
if (err)
goto exit;
/* Max. temp. 80C/90C/100C */
data->temp_therm[i] = 80;
data->temp_alert[i] = 90;
data->temp_ot[i] = 100;
err = i2c_smbus_write_byte_data(client,
MAX6639_REG_THERM_LIMIT(i),
data->temp_therm[i]);
if (err)
goto exit;
err = i2c_smbus_write_byte_data(client,
MAX6639_REG_ALERT_LIMIT(i),
data->temp_alert[i]);
if (err)
goto exit;
err = i2c_smbus_write_byte_data(client,
MAX6639_REG_OT_LIMIT(i), data->temp_ot[i]);
if (err)
goto exit;
/* PWM 120/120 (i.e. 100%) */
data->pwm[i] = 120;
err = i2c_smbus_write_byte_data(client,
MAX6639_REG_TARGTDUTY(i), data->pwm[i]);
if (err)
goto exit;
}
/* Start monitoring */
err = i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG,
MAX6639_GCONFIG_DISABLE_TIMEOUT | MAX6639_GCONFIG_CH2_LOCAL |
MAX6639_GCONFIG_PWM_FREQ_HI);
exit:
return err;
}
/* Return 0 if detection is successful, -ENODEV otherwise */
static int max6639_detect(struct i2c_client *client,
struct i2c_board_info *info)
{
struct i2c_adapter *adapter = client->adapter;
int dev_id, manu_id;
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
return -ENODEV;
/* Actual detection via device and manufacturer ID */
dev_id = i2c_smbus_read_byte_data(client, MAX6639_REG_DEVID);
manu_id = i2c_smbus_read_byte_data(client, MAX6639_REG_MANUID);
if (dev_id != 0x58 || manu_id != 0x4D)
return -ENODEV;
strlcpy(info->type, "max6639", I2C_NAME_SIZE);
return 0;
}
static int max6639_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct max6639_data *data;
int err;
data = devm_kzalloc(&client->dev, sizeof(struct max6639_data),
GFP_KERNEL);
if (!data)
return -ENOMEM;
i2c_set_clientdata(client, data);
mutex_init(&data->update_lock);
/* Initialize the max6639 chip */
err = max6639_init_client(client);
if (err < 0)
return err;
/* Register sysfs hooks */
err = sysfs_create_group(&client->dev.kobj, &max6639_group);
if (err)
return err;
data->hwmon_dev = hwmon_device_register(&client->dev);
if (IS_ERR(data->hwmon_dev)) {
err = PTR_ERR(data->hwmon_dev);
goto error_remove;
}
dev_info(&client->dev, "temperature sensor and fan control found\n");
return 0;
error_remove:
sysfs_remove_group(&client->dev.kobj, &max6639_group);
return err;
}
static int max6639_remove(struct i2c_client *client)
{
struct max6639_data *data = i2c_get_clientdata(client);
hwmon_device_unregister(data->hwmon_dev);
sysfs_remove_group(&client->dev.kobj, &max6639_group);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int max6639_suspend(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
int data = i2c_smbus_read_byte_data(client, MAX6639_REG_GCONFIG);
if (data < 0)
return data;
return i2c_smbus_write_byte_data(client,
MAX6639_REG_GCONFIG, data | MAX6639_GCONFIG_STANDBY);
}
static int max6639_resume(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
int data = i2c_smbus_read_byte_data(client, MAX6639_REG_GCONFIG);
if (data < 0)
return data;
return i2c_smbus_write_byte_data(client,
MAX6639_REG_GCONFIG, data & ~MAX6639_GCONFIG_STANDBY);
}
#endif /* CONFIG_PM_SLEEP */
static const struct i2c_device_id max6639_id[] = {
{"max6639", 0},
{ }
};
MODULE_DEVICE_TABLE(i2c, max6639_id);
static const struct dev_pm_ops max6639_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(max6639_suspend, max6639_resume)
};
static struct i2c_driver max6639_driver = {
.class = I2C_CLASS_HWMON,
.driver = {
.name = "max6639",
.pm = &max6639_pm_ops,
},
.probe = max6639_probe,
.remove = max6639_remove,
.id_table = max6639_id,
.detect = max6639_detect,
.address_list = normal_i2c,
};
module_i2c_driver(max6639_driver);
MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
MODULE_DESCRIPTION("max6639 driver");
MODULE_LICENSE("GPL");
