| /* |
| ds1621.c - Part of lm_sensors, Linux kernel modules for hardware |
| monitoring |
| Christian W. Zuckschwerdt <zany@triq.net> 2000-11-23 |
| based on lm75.c by Frodo Looijaard <frodol@dds.nl> |
| Ported to Linux 2.6 by Aurelien Jarno <aurelien@aurel32.net> with |
| the help of Jean Delvare <khali@linux-fr.org> |
| |
| 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> |
| #include "lm75.h" |
| |
| /* Addresses to scan */ |
| static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b, 0x4c, |
| 0x4d, 0x4e, 0x4f, I2C_CLIENT_END }; |
| |
| /* Insmod parameters */ |
| I2C_CLIENT_INSMOD_1(ds1621); |
| static int polarity = -1; |
| module_param(polarity, int, 0); |
| MODULE_PARM_DESC(polarity, "Output's polarity: 0 = active high, 1 = active low"); |
| |
| /* Many DS1621 constants specified below */ |
| /* Config register used for detection */ |
| /* 7 6 5 4 3 2 1 0 */ |
| /* |Done|THF |TLF |NVB | X | X |POL |1SHOT| */ |
| #define DS1621_REG_CONFIG_NVB 0x10 |
| #define DS1621_REG_CONFIG_POLARITY 0x02 |
| #define DS1621_REG_CONFIG_1SHOT 0x01 |
| #define DS1621_REG_CONFIG_DONE 0x80 |
| |
| /* The DS1621 registers */ |
| static const u8 DS1621_REG_TEMP[3] = { |
| 0xAA, /* input, word, RO */ |
| 0xA2, /* min, word, RW */ |
| 0xA1, /* max, word, RW */ |
| }; |
| #define DS1621_REG_CONF 0xAC /* byte, RW */ |
| #define DS1621_COM_START 0xEE /* no data */ |
| #define DS1621_COM_STOP 0x22 /* no data */ |
| |
| /* The DS1621 configuration register */ |
| #define DS1621_ALARM_TEMP_HIGH 0x40 |
| #define DS1621_ALARM_TEMP_LOW 0x20 |
| |
| /* Conversions */ |
| #define ALARMS_FROM_REG(val) ((val) & \ |
| (DS1621_ALARM_TEMP_HIGH | DS1621_ALARM_TEMP_LOW)) |
| |
| /* Each client has this additional data */ |
| struct ds1621_data { |
| struct device *hwmon_dev; |
| struct mutex update_lock; |
| char valid; /* !=0 if following fields are valid */ |
| unsigned long last_updated; /* In jiffies */ |
| |
| u16 temp[3]; /* Register values, word */ |
| u8 conf; /* Register encoding, combined */ |
| }; |
| |
| /* Temperature registers are word-sized. |
| DS1621 uses a high-byte first convention, which is exactly opposite to |
| the SMBus standard. */ |
| static int ds1621_read_temp(struct i2c_client *client, u8 reg) |
| { |
| int ret; |
| |
| ret = i2c_smbus_read_word_data(client, reg); |
| if (ret < 0) |
| return ret; |
| return swab16(ret); |
| } |
| |
| static int ds1621_write_temp(struct i2c_client *client, u8 reg, u16 value) |
| { |
| return i2c_smbus_write_word_data(client, reg, swab16(value)); |
| } |
| |
| static void ds1621_init_client(struct i2c_client *client) |
| { |
| u8 conf, new_conf; |
| |
| new_conf = conf = i2c_smbus_read_byte_data(client, DS1621_REG_CONF); |
| /* switch to continuous conversion mode */ |
| new_conf &= ~DS1621_REG_CONFIG_1SHOT; |
| |
| /* setup output polarity */ |
| if (polarity == 0) |
| new_conf &= ~DS1621_REG_CONFIG_POLARITY; |
| else if (polarity == 1) |
| new_conf |= DS1621_REG_CONFIG_POLARITY; |
| |
| if (conf != new_conf) |
| i2c_smbus_write_byte_data(client, DS1621_REG_CONF, new_conf); |
| |
| /* start conversion */ |
| i2c_smbus_write_byte(client, DS1621_COM_START); |
| } |
| |
| static struct ds1621_data *ds1621_update_client(struct device *dev) |
| { |
| struct i2c_client *client = to_i2c_client(dev); |
| struct ds1621_data *data = i2c_get_clientdata(client); |
| u8 new_conf; |
| |
| mutex_lock(&data->update_lock); |
| |
| if (time_after(jiffies, data->last_updated + HZ + HZ / 2) |
| || !data->valid) { |
| int i; |
| |
| dev_dbg(&client->dev, "Starting ds1621 update\n"); |
| |
| data->conf = i2c_smbus_read_byte_data(client, DS1621_REG_CONF); |
| |
| for (i = 0; i < ARRAY_SIZE(data->temp); i++) |
| data->temp[i] = ds1621_read_temp(client, |
| DS1621_REG_TEMP[i]); |
| |
| /* reset alarms if necessary */ |
| new_conf = data->conf; |
| if (data->temp[0] > data->temp[1]) /* input > min */ |
| new_conf &= ~DS1621_ALARM_TEMP_LOW; |
| if (data->temp[0] < data->temp[2]) /* input < max */ |
| new_conf &= ~DS1621_ALARM_TEMP_HIGH; |
| if (data->conf != new_conf) |
| i2c_smbus_write_byte_data(client, DS1621_REG_CONF, |
| new_conf); |
| |
| data->last_updated = jiffies; |
| data->valid = 1; |
| } |
| |
| mutex_unlock(&data->update_lock); |
| |
| return data; |
| } |
| |
| static ssize_t show_temp(struct device *dev, struct device_attribute *da, |
| char *buf) |
| { |
| struct sensor_device_attribute *attr = to_sensor_dev_attr(da); |
| struct ds1621_data *data = ds1621_update_client(dev); |
| return sprintf(buf, "%d\n", |
| LM75_TEMP_FROM_REG(data->temp[attr->index])); |
| } |
| |
| static ssize_t set_temp(struct device *dev, struct device_attribute *da, |
| const char *buf, size_t count) |
| { |
| struct sensor_device_attribute *attr = to_sensor_dev_attr(da); |
| struct i2c_client *client = to_i2c_client(dev); |
| struct ds1621_data *data = i2c_get_clientdata(client); |
| u16 val = LM75_TEMP_TO_REG(simple_strtol(buf, NULL, 10)); |
| |
| mutex_lock(&data->update_lock); |
| data->temp[attr->index] = val; |
| ds1621_write_temp(client, DS1621_REG_TEMP[attr->index], |
| data->temp[attr->index]); |
| mutex_unlock(&data->update_lock); |
| return count; |
| } |
| |
| static ssize_t show_alarms(struct device *dev, struct device_attribute *da, |
| char *buf) |
| { |
| struct ds1621_data *data = ds1621_update_client(dev); |
| return sprintf(buf, "%d\n", ALARMS_FROM_REG(data->conf)); |
| } |
| |
| static ssize_t show_alarm(struct device *dev, struct device_attribute *da, |
| char *buf) |
| { |
| struct sensor_device_attribute *attr = to_sensor_dev_attr(da); |
| struct ds1621_data *data = ds1621_update_client(dev); |
| return sprintf(buf, "%d\n", !!(data->conf & attr->index)); |
| } |
| |
| static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL); |
| static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0); |
| static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, show_temp, set_temp, 1); |
| static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp, set_temp, 2); |
| static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL, |
| DS1621_ALARM_TEMP_LOW); |
| static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, |
| DS1621_ALARM_TEMP_HIGH); |
| |
| static struct attribute *ds1621_attributes[] = { |
| &sensor_dev_attr_temp1_input.dev_attr.attr, |
| &sensor_dev_attr_temp1_min.dev_attr.attr, |
| &sensor_dev_attr_temp1_max.dev_attr.attr, |
| &sensor_dev_attr_temp1_min_alarm.dev_attr.attr, |
| &sensor_dev_attr_temp1_max_alarm.dev_attr.attr, |
| &dev_attr_alarms.attr, |
| NULL |
| }; |
| |
| static const struct attribute_group ds1621_group = { |
| .attrs = ds1621_attributes, |
| }; |
| |
| |
| /* Return 0 if detection is successful, -ENODEV otherwise */ |
| static int ds1621_detect(struct i2c_client *client, |
| struct i2c_board_info *info) |
| { |
| struct i2c_adapter *adapter = client->adapter; |
| int conf, temp; |
| int i; |
| |
| if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
| | I2C_FUNC_SMBUS_WORD_DATA |
| | I2C_FUNC_SMBUS_WRITE_BYTE)) |
| return -ENODEV; |
| |
| /* Now, we do the remaining detection. It is lousy. */ |
| /* The NVB bit should be low if no EEPROM write has been requested |
| during the latest 10ms, which is highly improbable in our case. */ |
| conf = i2c_smbus_read_byte_data(client, DS1621_REG_CONF); |
| if (conf < 0 || conf & DS1621_REG_CONFIG_NVB) |
| return -ENODEV; |
| /* The 7 lowest bits of a temperature should always be 0. */ |
| for (i = 0; i < ARRAY_SIZE(DS1621_REG_TEMP); i++) { |
| temp = i2c_smbus_read_word_data(client, DS1621_REG_TEMP[i]); |
| if (temp < 0 || (temp & 0x7f00)) |
| return -ENODEV; |
| } |
| |
| strlcpy(info->type, "ds1621", I2C_NAME_SIZE); |
| |
| return 0; |
| } |
| |
| static int ds1621_probe(struct i2c_client *client, |
| const struct i2c_device_id *id) |
| { |
| struct ds1621_data *data; |
| int err; |
| |
| data = kzalloc(sizeof(struct ds1621_data), GFP_KERNEL); |
| if (!data) { |
| err = -ENOMEM; |
| goto exit; |
| } |
| |
| i2c_set_clientdata(client, data); |
| mutex_init(&data->update_lock); |
| |
| /* Initialize the DS1621 chip */ |
| ds1621_init_client(client); |
| |
| /* Register sysfs hooks */ |
| if ((err = sysfs_create_group(&client->dev.kobj, &ds1621_group))) |
| goto exit_free; |
| |
| data->hwmon_dev = hwmon_device_register(&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(&client->dev.kobj, &ds1621_group); |
| exit_free: |
| kfree(data); |
| exit: |
| return err; |
| } |
| |
| static int ds1621_remove(struct i2c_client *client) |
| { |
| struct ds1621_data *data = i2c_get_clientdata(client); |
| |
| hwmon_device_unregister(data->hwmon_dev); |
| sysfs_remove_group(&client->dev.kobj, &ds1621_group); |
| |
| kfree(data); |
| |
| return 0; |
| } |
| |
| static const struct i2c_device_id ds1621_id[] = { |
| { "ds1621", ds1621 }, |
| { "ds1625", ds1621 }, |
| { } |
| }; |
| MODULE_DEVICE_TABLE(i2c, ds1621_id); |
| |
| /* This is the driver that will be inserted */ |
| static struct i2c_driver ds1621_driver = { |
| .class = I2C_CLASS_HWMON, |
| .driver = { |
| .name = "ds1621", |
| }, |
| .probe = ds1621_probe, |
| .remove = ds1621_remove, |
| .id_table = ds1621_id, |
| .detect = ds1621_detect, |
| .address_list = normal_i2c, |
| }; |
| |
| static int __init ds1621_init(void) |
| { |
| return i2c_add_driver(&ds1621_driver); |
| } |
| |
| static void __exit ds1621_exit(void) |
| { |
| i2c_del_driver(&ds1621_driver); |
| } |
| |
| |
| MODULE_AUTHOR("Christian W. Zuckschwerdt <zany@triq.net>"); |
| MODULE_DESCRIPTION("DS1621 driver"); |
| MODULE_LICENSE("GPL"); |
| |
| module_init(ds1621_init); |
| module_exit(ds1621_exit); |