/*
* emc1403.c - SMSC Thermal Driver
*
* Copyright (C) 2008 Intel Corp
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
* 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; version 2 of the License.
*
* 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.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
* TODO
* - cache alarm and critical limit registers
* - add emc1404 support
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/err.h>
#include <linux/sysfs.h>
#include <linux/mutex.h>
#define THERMAL_PID_REG 0xfd
#define THERMAL_SMSC_ID_REG 0xfe
#define THERMAL_REVISION_REG 0xff
struct thermal_data {
struct device *hwmon_dev;
struct mutex mutex;
/* Cache the hyst value so we don't keep re-reading it. In theory
we could cache it forever as nobody else should be writing it. */
u8 cached_hyst;
unsigned long hyst_valid;
};
static ssize_t show_temp(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct i2c_client *client = to_i2c_client(dev);
struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
int retval = i2c_smbus_read_byte_data(client, sda->index);
if (retval < 0)
return retval;
return sprintf(buf, "%d000\n", retval);
}
static ssize_t show_bit(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct i2c_client *client = to_i2c_client(dev);
struct sensor_device_attribute_2 *sda = to_sensor_dev_attr_2(attr);
int retval = i2c_smbus_read_byte_data(client, sda->nr);
if (retval < 0)
return retval;
retval &= sda->index;
return sprintf(buf, "%d\n", retval ? 1 : 0);
}
static ssize_t store_temp(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
struct i2c_client *client = to_i2c_client(dev);
unsigned long val;
int retval;
if (strict_strtoul(buf, 10, &val))
return -EINVAL;
retval = i2c_smbus_write_byte_data(client, sda->index,
DIV_ROUND_CLOSEST(val, 1000));
if (retval < 0)
return retval;
return count;
}
static ssize_t store_bit(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
struct i2c_client *client = to_i2c_client(dev);
struct thermal_data *data = i2c_get_clientdata(client);
struct sensor_device_attribute_2 *sda = to_sensor_dev_attr_2(attr);
unsigned long val;
int retval;
if (strict_strtoul(buf, 10, &val))
return -EINVAL;
mutex_lock(&data->mutex);
retval = i2c_smbus_read_byte_data(client, sda->nr);
if (retval < 0)
goto fail;
retval &= ~sda->index;
if (val)
retval |= sda->index;
retval = i2c_smbus_write_byte_data(client, sda->index, retval);
if (retval == 0)
retval = count;
fail:
mutex_unlock(&data->mutex);
return retval;
}
static ssize_t show_hyst(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct i2c_client *client = to_i2c_client(dev);
struct thermal_data *data = i2c_get_clientdata(client);
struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
int retval;
int hyst;
retval = i2c_smbus_read_byte_data(client, sda->index);
if (retval < 0)
return retval;
if (time_after(jiffies, data->hyst_valid)) {
hyst = i2c_smbus_read_byte_data(client, 0x21);
if (hyst < 0)
return retval;
data->cached_hyst = hyst;
data->hyst_valid = jiffies + HZ;
}
return sprintf(buf, "%d000\n", retval - data->cached_hyst);
}
static ssize_t store_hyst(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
struct i2c_client *client = to_i2c_client(dev);
struct thermal_data *data = i2c_get_clientdata(client);
struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
int retval;
int hyst;
unsigned long val;
if (strict_strtoul(buf, 10, &val))
return -EINVAL;
mutex_lock(&data->mutex);
retval = i2c_smbus_read_byte_data(client, sda->index);
if (retval < 0)
goto fail;
hyst = val - retval * 1000;
hyst = DIV_ROUND_CLOSEST(hyst, 1000);
if (hyst < 0 || hyst > 255) {
retval = -ERANGE;
goto fail;
}
retval = i2c_smbus_write_byte_data(client, 0x21, hyst);
if (retval == 0) {
retval = count;
data->cached_hyst = hyst;
data->hyst_valid = jiffies + HZ;
}
fail:
mutex_unlock(&data->mutex);
return retval;
}
/*
* Sensors. We pass the actual i2c register to the methods.
*/
static SENSOR_DEVICE_ATTR(temp1_min, S_IRUGO | S_IWUSR,
show_temp, store_temp, 0x06);
static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO | S_IWUSR,
show_temp, store_temp, 0x05);
static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO | S_IWUSR,
show_temp, store_temp, 0x20);
static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0x00);
static SENSOR_DEVICE_ATTR_2(temp1_min_alarm, S_IRUGO,
show_bit, NULL, 0x36, 0x01);
static SENSOR_DEVICE_ATTR_2(temp1_max_alarm, S_IRUGO,
show_bit, NULL, 0x35, 0x01);
static SENSOR_DEVICE_ATTR_2(temp1_crit_alarm, S_IRUGO,
show_bit, NULL, 0x37, 0x01);
static SENSOR_DEVICE_ATTR(temp1_crit_hyst, S_IRUGO | S_IWUSR,
show_hyst, store_hyst, 0x20);
static SENSOR_DEVICE_ATTR(temp2_min, S_IRUGO | S_IWUSR,
show_temp, store_temp, 0x08);
static SENSOR_DEVICE_ATTR(temp2_max, S_IRUGO | S_IWUSR,
show_temp, store_temp, 0x07);
static SENSOR_DEVICE_ATTR(temp2_crit, S_IRUGO | S_IWUSR,
show_temp, store_temp, 0x19);
static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, 0x01);
static SENSOR_DEVICE_ATTR_2(temp2_min_alarm, S_IRUGO,
show_bit, NULL, 0x36, 0x02);
static SENSOR_DEVICE_ATTR_2(temp2_max_alarm, S_IRUGO,
show_bit, NULL, 0x35, 0x02);
static SENSOR_DEVICE_ATTR_2(temp2_crit_alarm, S_IRUGO,
show_bit, NULL, 0x37, 0x02);
static SENSOR_DEVICE_ATTR(temp2_crit_hyst, S_IRUGO | S_IWUSR,
show_hyst, store_hyst, 0x19);
static SENSOR_DEVICE_ATTR(temp3_min, S_IRUGO | S_IWUSR,
show_temp, store_temp, 0x16);
static SENSOR_DEVICE_ATTR(temp3_max, S_IRUGO | S_IWUSR,
show_temp, store_temp, 0x15);
static SENSOR_DEVICE_ATTR(temp3_crit, S_IRUGO | S_IWUSR,
show_temp, store_temp, 0x1A);
static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp, NULL, 0x23);
static SENSOR_DEVICE_ATTR_2(temp3_min_alarm, S_IRUGO,
show_bit, NULL, 0x36, 0x04);
static SENSOR_DEVICE_ATTR_2(temp3_max_alarm, S_IRUGO,
show_bit, NULL, 0x35, 0x04);
static SENSOR_DEVICE_ATTR_2(temp3_crit_alarm, S_IRUGO,
show_bit, NULL, 0x37, 0x04);
static SENSOR_DEVICE_ATTR(temp3_crit_hyst, S_IRUGO | S_IWUSR,
show_hyst, store_hyst, 0x1A);
static SENSOR_DEVICE_ATTR_2(power_state, S_IRUGO | S_IWUSR,
show_bit, store_bit, 0x03, 0x40);
static struct attribute *mid_att_thermal[] = {
&sensor_dev_attr_temp1_min.dev_attr.attr,
&sensor_dev_attr_temp1_max.dev_attr.attr,
&sensor_dev_attr_temp1_crit.dev_attr.attr,
&sensor_dev_attr_temp1_input.dev_attr.attr,
&sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
&sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
&sensor_dev_attr_temp1_crit_hyst.dev_attr.attr,
&sensor_dev_attr_temp2_min.dev_attr.attr,
&sensor_dev_attr_temp2_max.dev_attr.attr,
&sensor_dev_attr_temp2_crit.dev_attr.attr,
&sensor_dev_attr_temp2_input.dev_attr.attr,
&sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
&sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
&sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
&sensor_dev_attr_temp2_crit_hyst.dev_attr.attr,
&sensor_dev_attr_temp3_min.dev_attr.attr,
&sensor_dev_attr_temp3_max.dev_attr.attr,
&sensor_dev_attr_temp3_crit.dev_attr.attr,
&sensor_dev_attr_temp3_input.dev_attr.attr,
&sensor_dev_attr_temp3_min_alarm.dev_attr.attr,
&sensor_dev_attr_temp3_max_alarm.dev_attr.attr,
&sensor_dev_attr_temp3_crit_alarm.dev_attr.attr,
&sensor_dev_attr_temp3_crit_hyst.dev_attr.attr,
&sensor_dev_attr_power_state.dev_attr.attr,
NULL
};
static const struct attribute_group m_thermal_gr = {
.attrs = mid_att_thermal
};
static int emc1403_detect(struct i2c_client *client,
struct i2c_board_info *info)
{
int id;
/* Check if thermal chip is SMSC and EMC1403 or EMC1423 */
id = i2c_smbus_read_byte_data(client, THERMAL_SMSC_ID_REG);
if (id != 0x5d)
return -ENODEV;
id = i2c_smbus_read_byte_data(client, THERMAL_PID_REG);
switch (id) {
case 0x21:
strlcpy(info->type, "emc1403", I2C_NAME_SIZE);
break;
case 0x23:
strlcpy(info->type, "emc1423", I2C_NAME_SIZE);
break;
/* Note: 0x25 is the 1404 which is very similar and this
driver could be extended */
default:
return -ENODEV;
}
id = i2c_smbus_read_byte_data(client, THERMAL_REVISION_REG);
if (id != 0x01)
return -ENODEV;
return 0;
}
static int emc1403_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
int res;
struct thermal_data *data;
data = kzalloc(sizeof(struct thermal_data), GFP_KERNEL);
if (data == NULL) {
dev_warn(&client->dev, "out of memory");
return -ENOMEM;
}
i2c_set_clientdata(client, data);
mutex_init(&data->mutex);
data->hyst_valid = jiffies - 1; /* Expired */
res = sysfs_create_group(&client->dev.kobj, &m_thermal_gr);
if (res) {
dev_warn(&client->dev, "create group failed\n");
goto thermal_error1;
}
data->hwmon_dev = hwmon_device_register(&client->dev);
if (IS_ERR(data->hwmon_dev)) {
res = PTR_ERR(data->hwmon_dev);
dev_warn(&client->dev, "register hwmon dev failed\n");
goto thermal_error2;
}
dev_info(&client->dev, "EMC1403 Thermal chip found\n");
return res;
thermal_error2:
sysfs_remove_group(&client->dev.kobj, &m_thermal_gr);
thermal_error1:
kfree(data);
return res;
}
static int emc1403_remove(struct i2c_client *client)
{
struct thermal_data *data = i2c_get_clientdata(client);
hwmon_device_unregister(data->hwmon_dev);
sysfs_remove_group(&client->dev.kobj, &m_thermal_gr);
kfree(data);
return 0;
}
static const unsigned short emc1403_address_list[] = {
0x18, 0x29, 0x4c, 0x4d, I2C_CLIENT_END
};
static const struct i2c_device_id emc1403_idtable[] = {
{ "emc1403", 0 },
{ "emc1423", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, emc1403_idtable);
static struct i2c_driver sensor_emc1403 = {
.class = I2C_CLASS_HWMON,
.driver = {
.name = "emc1403",
},
.detect = emc1403_detect,
.probe = emc1403_probe,
.remove = emc1403_remove,
.id_table = emc1403_idtable,
.address_list = emc1403_address_list,
};
static int __init sensor_emc1403_init(void)
{
return i2c_add_driver(&sensor_emc1403);
}
static void __exit sensor_emc1403_exit(void)
{
i2c_del_driver(&sensor_emc1403);
}
module_init(sensor_emc1403_init);
module_exit(sensor_emc1403_exit);
MODULE_AUTHOR("Kalhan Trisal <kalhan.trisal@intel.com");
MODULE_DESCRIPTION("emc1403 Thermal Driver");
MODULE_LICENSE("GPL v2");
