|  | /* | 
|  | * Copyright (C) 2008, 2010 Davide Rizzo <elpa.rizzo@gmail.com> | 
|  | * | 
|  | * The LM95241 is a sensor chip made by National Semiconductors. | 
|  | * It reports up to three temperatures (its own plus up to two external ones). | 
|  | * Complete datasheet can be obtained from National's website at: | 
|  | *   http://www.national.com/ds.cgi/LM/LM95241.pdf | 
|  | * | 
|  | * 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> | 
|  |  | 
|  | #define DEVNAME "lm95241" | 
|  |  | 
|  | static const unsigned short normal_i2c[] = { | 
|  | 0x19, 0x2a, 0x2b, I2C_CLIENT_END }; | 
|  |  | 
|  | /* LM95241 registers */ | 
|  | #define LM95241_REG_R_MAN_ID		0xFE | 
|  | #define LM95241_REG_R_CHIP_ID		0xFF | 
|  | #define LM95241_REG_R_STATUS		0x02 | 
|  | #define LM95241_REG_RW_CONFIG		0x03 | 
|  | #define LM95241_REG_RW_REM_FILTER	0x06 | 
|  | #define LM95241_REG_RW_TRUTHERM		0x07 | 
|  | #define LM95241_REG_W_ONE_SHOT		0x0F | 
|  | #define LM95241_REG_R_LOCAL_TEMPH	0x10 | 
|  | #define LM95241_REG_R_REMOTE1_TEMPH	0x11 | 
|  | #define LM95241_REG_R_REMOTE2_TEMPH	0x12 | 
|  | #define LM95241_REG_R_LOCAL_TEMPL	0x20 | 
|  | #define LM95241_REG_R_REMOTE1_TEMPL	0x21 | 
|  | #define LM95241_REG_R_REMOTE2_TEMPL	0x22 | 
|  | #define LM95241_REG_RW_REMOTE_MODEL	0x30 | 
|  |  | 
|  | /* LM95241 specific bitfields */ | 
|  | #define CFG_STOP 0x40 | 
|  | #define CFG_CR0076 0x00 | 
|  | #define CFG_CR0182 0x10 | 
|  | #define CFG_CR1000 0x20 | 
|  | #define CFG_CR2700 0x30 | 
|  | #define R1MS_SHIFT 0 | 
|  | #define R2MS_SHIFT 2 | 
|  | #define R1MS_MASK (0x01 << (R1MS_SHIFT)) | 
|  | #define R2MS_MASK (0x01 << (R2MS_SHIFT)) | 
|  | #define R1DF_SHIFT 1 | 
|  | #define R2DF_SHIFT 2 | 
|  | #define R1DF_MASK (0x01 << (R1DF_SHIFT)) | 
|  | #define R2DF_MASK (0x01 << (R2DF_SHIFT)) | 
|  | #define R1FE_MASK 0x01 | 
|  | #define R2FE_MASK 0x05 | 
|  | #define TT1_SHIFT 0 | 
|  | #define TT2_SHIFT 4 | 
|  | #define TT_OFF 0 | 
|  | #define TT_ON 1 | 
|  | #define TT_MASK 7 | 
|  | #define MANUFACTURER_ID 0x01 | 
|  | #define DEFAULT_REVISION 0xA4 | 
|  |  | 
|  | static const u8 lm95241_reg_address[] = { | 
|  | LM95241_REG_R_LOCAL_TEMPH, | 
|  | LM95241_REG_R_LOCAL_TEMPL, | 
|  | LM95241_REG_R_REMOTE1_TEMPH, | 
|  | LM95241_REG_R_REMOTE1_TEMPL, | 
|  | LM95241_REG_R_REMOTE2_TEMPH, | 
|  | LM95241_REG_R_REMOTE2_TEMPL | 
|  | }; | 
|  |  | 
|  | /* Client data (each client gets its own) */ | 
|  | struct lm95241_data { | 
|  | struct device *hwmon_dev; | 
|  | struct mutex update_lock; | 
|  | unsigned long last_updated, interval;	/* in jiffies */ | 
|  | char valid;		/* zero until following fields are valid */ | 
|  | /* registers values */ | 
|  | u8 temp[ARRAY_SIZE(lm95241_reg_address)]; | 
|  | u8 config, model, trutherm; | 
|  | }; | 
|  |  | 
|  | /* Conversions */ | 
|  | static int TempFromReg(u8 val_h, u8 val_l) | 
|  | { | 
|  | if (val_h & 0x80) | 
|  | return val_h - 0x100; | 
|  | return val_h * 1000 + val_l * 1000 / 256; | 
|  | } | 
|  |  | 
|  | static struct lm95241_data *lm95241_update_device(struct device *dev) | 
|  | { | 
|  | struct i2c_client *client = to_i2c_client(dev); | 
|  | struct lm95241_data *data = i2c_get_clientdata(client); | 
|  |  | 
|  | mutex_lock(&data->update_lock); | 
|  |  | 
|  | if (time_after(jiffies, data->last_updated + data->interval) || | 
|  | !data->valid) { | 
|  | int i; | 
|  |  | 
|  | dev_dbg(&client->dev, "Updating lm95241 data.\n"); | 
|  | for (i = 0; i < ARRAY_SIZE(lm95241_reg_address); i++) | 
|  | data->temp[i] | 
|  | = i2c_smbus_read_byte_data(client, | 
|  | lm95241_reg_address[i]); | 
|  | data->last_updated = jiffies; | 
|  | data->valid = 1; | 
|  | } | 
|  |  | 
|  | mutex_unlock(&data->update_lock); | 
|  |  | 
|  | return data; | 
|  | } | 
|  |  | 
|  | /* Sysfs stuff */ | 
|  | static ssize_t show_input(struct device *dev, struct device_attribute *attr, | 
|  | char *buf) | 
|  | { | 
|  | struct lm95241_data *data = lm95241_update_device(dev); | 
|  |  | 
|  | return snprintf(buf, PAGE_SIZE - 1, "%d\n", | 
|  | TempFromReg(data->temp[to_sensor_dev_attr(attr)->index], | 
|  | data->temp[to_sensor_dev_attr(attr)->index + 1])); | 
|  | } | 
|  |  | 
|  | static ssize_t show_type(struct device *dev, struct device_attribute *attr, | 
|  | char *buf) | 
|  | { | 
|  | struct i2c_client *client = to_i2c_client(dev); | 
|  | struct lm95241_data *data = i2c_get_clientdata(client); | 
|  |  | 
|  | return snprintf(buf, PAGE_SIZE - 1, | 
|  | data->model & to_sensor_dev_attr(attr)->index ? "1\n" : "2\n"); | 
|  | } | 
|  |  | 
|  | static ssize_t set_type(struct device *dev, struct device_attribute *attr, | 
|  | const char *buf, size_t count) | 
|  | { | 
|  | struct i2c_client *client = to_i2c_client(dev); | 
|  | struct lm95241_data *data = i2c_get_clientdata(client); | 
|  | unsigned long val; | 
|  | int shift; | 
|  | u8 mask = to_sensor_dev_attr(attr)->index; | 
|  |  | 
|  | if (strict_strtoul(buf, 10, &val) < 0) | 
|  | return -EINVAL; | 
|  | if (val != 1 && val != 2) | 
|  | return -EINVAL; | 
|  |  | 
|  | shift = mask == R1MS_MASK ? TT1_SHIFT : TT2_SHIFT; | 
|  |  | 
|  | mutex_lock(&data->update_lock); | 
|  |  | 
|  | data->trutherm &= ~(TT_MASK << shift); | 
|  | if (val == 1) { | 
|  | data->model |= mask; | 
|  | data->trutherm |= (TT_ON << shift); | 
|  | } else { | 
|  | data->model &= ~mask; | 
|  | data->trutherm |= (TT_OFF << shift); | 
|  | } | 
|  | data->valid = 0; | 
|  |  | 
|  | i2c_smbus_write_byte_data(client, LM95241_REG_RW_REMOTE_MODEL, | 
|  | data->model); | 
|  | i2c_smbus_write_byte_data(client, LM95241_REG_RW_TRUTHERM, | 
|  | data->trutherm); | 
|  |  | 
|  | mutex_unlock(&data->update_lock); | 
|  |  | 
|  | return count; | 
|  | } | 
|  |  | 
|  | static ssize_t show_min(struct device *dev, struct device_attribute *attr, | 
|  | char *buf) | 
|  | { | 
|  | struct i2c_client *client = to_i2c_client(dev); | 
|  | struct lm95241_data *data = i2c_get_clientdata(client); | 
|  |  | 
|  | return snprintf(buf, PAGE_SIZE - 1, | 
|  | data->config & to_sensor_dev_attr(attr)->index ? | 
|  | "-127000\n" : "0\n"); | 
|  | } | 
|  |  | 
|  | static ssize_t set_min(struct device *dev, struct device_attribute *attr, | 
|  | const char *buf, size_t count) | 
|  | { | 
|  | struct i2c_client *client = to_i2c_client(dev); | 
|  | struct lm95241_data *data = i2c_get_clientdata(client); | 
|  | long val; | 
|  |  | 
|  | if (strict_strtol(buf, 10, &val) < 0) | 
|  | return -EINVAL; | 
|  | if (val < -128000) | 
|  | return -EINVAL; | 
|  |  | 
|  | mutex_lock(&data->update_lock); | 
|  |  | 
|  | if (val < 0) | 
|  | data->config |= to_sensor_dev_attr(attr)->index; | 
|  | else | 
|  | data->config &= ~to_sensor_dev_attr(attr)->index; | 
|  | data->valid = 0; | 
|  |  | 
|  | i2c_smbus_write_byte_data(client, LM95241_REG_RW_CONFIG, data->config); | 
|  |  | 
|  | mutex_unlock(&data->update_lock); | 
|  |  | 
|  | return count; | 
|  | } | 
|  |  | 
|  | static ssize_t show_max(struct device *dev, struct device_attribute *attr, | 
|  | char *buf) | 
|  | { | 
|  | struct i2c_client *client = to_i2c_client(dev); | 
|  | struct lm95241_data *data = i2c_get_clientdata(client); | 
|  |  | 
|  | return snprintf(buf, PAGE_SIZE - 1, | 
|  | data->config & to_sensor_dev_attr(attr)->index ? | 
|  | "127000\n" : "255000\n"); | 
|  | } | 
|  |  | 
|  | static ssize_t set_max(struct device *dev, struct device_attribute *attr, | 
|  | const char *buf, size_t count) | 
|  | { | 
|  | struct i2c_client *client = to_i2c_client(dev); | 
|  | struct lm95241_data *data = i2c_get_clientdata(client); | 
|  | long val; | 
|  |  | 
|  | if (strict_strtol(buf, 10, &val) < 0) | 
|  | return -EINVAL; | 
|  | if (val >= 256000) | 
|  | return -EINVAL; | 
|  |  | 
|  | mutex_lock(&data->update_lock); | 
|  |  | 
|  | if (val <= 127000) | 
|  | data->config |= to_sensor_dev_attr(attr)->index; | 
|  | else | 
|  | data->config &= ~to_sensor_dev_attr(attr)->index; | 
|  | data->valid = 0; | 
|  |  | 
|  | i2c_smbus_write_byte_data(client, LM95241_REG_RW_CONFIG, data->config); | 
|  |  | 
|  | mutex_unlock(&data->update_lock); | 
|  |  | 
|  | return count; | 
|  | } | 
|  |  | 
|  | static ssize_t show_interval(struct device *dev, struct device_attribute *attr, | 
|  | char *buf) | 
|  | { | 
|  | struct lm95241_data *data = lm95241_update_device(dev); | 
|  |  | 
|  | return snprintf(buf, PAGE_SIZE - 1, "%lu\n", 1000 * data->interval | 
|  | / HZ); | 
|  | } | 
|  |  | 
|  | static ssize_t set_interval(struct device *dev, struct device_attribute *attr, | 
|  | const char *buf, size_t count) | 
|  | { | 
|  | struct i2c_client *client = to_i2c_client(dev); | 
|  | struct lm95241_data *data = i2c_get_clientdata(client); | 
|  | unsigned long val; | 
|  |  | 
|  | if (strict_strtoul(buf, 10, &val) < 0) | 
|  | return -EINVAL; | 
|  |  | 
|  | data->interval = val * HZ / 1000; | 
|  |  | 
|  | return count; | 
|  | } | 
|  |  | 
|  | static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_input, NULL, 0); | 
|  | static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_input, NULL, 2); | 
|  | static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_input, NULL, 4); | 
|  | static SENSOR_DEVICE_ATTR(temp2_type, S_IWUSR | S_IRUGO, show_type, set_type, | 
|  | R1MS_MASK); | 
|  | static SENSOR_DEVICE_ATTR(temp3_type, S_IWUSR | S_IRUGO, show_type, set_type, | 
|  | R2MS_MASK); | 
|  | static SENSOR_DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_min, set_min, | 
|  | R1DF_MASK); | 
|  | static SENSOR_DEVICE_ATTR(temp3_min, S_IWUSR | S_IRUGO, show_min, set_min, | 
|  | R2DF_MASK); | 
|  | static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_max, set_max, | 
|  | R1DF_MASK); | 
|  | static SENSOR_DEVICE_ATTR(temp3_max, S_IWUSR | S_IRUGO, show_max, set_max, | 
|  | R2DF_MASK); | 
|  | static DEVICE_ATTR(update_interval, S_IWUSR | S_IRUGO, show_interval, | 
|  | set_interval); | 
|  |  | 
|  | static struct attribute *lm95241_attributes[] = { | 
|  | &sensor_dev_attr_temp1_input.dev_attr.attr, | 
|  | &sensor_dev_attr_temp2_input.dev_attr.attr, | 
|  | &sensor_dev_attr_temp3_input.dev_attr.attr, | 
|  | &sensor_dev_attr_temp2_type.dev_attr.attr, | 
|  | &sensor_dev_attr_temp3_type.dev_attr.attr, | 
|  | &sensor_dev_attr_temp2_min.dev_attr.attr, | 
|  | &sensor_dev_attr_temp3_min.dev_attr.attr, | 
|  | &sensor_dev_attr_temp2_max.dev_attr.attr, | 
|  | &sensor_dev_attr_temp3_max.dev_attr.attr, | 
|  | &dev_attr_update_interval.attr, | 
|  | NULL | 
|  | }; | 
|  |  | 
|  | static const struct attribute_group lm95241_group = { | 
|  | .attrs = lm95241_attributes, | 
|  | }; | 
|  |  | 
|  | /* Return 0 if detection is successful, -ENODEV otherwise */ | 
|  | static int lm95241_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; | 
|  |  | 
|  | if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) | 
|  | return -ENODEV; | 
|  |  | 
|  | if ((i2c_smbus_read_byte_data(new_client, LM95241_REG_R_MAN_ID) | 
|  | == MANUFACTURER_ID) | 
|  | && (i2c_smbus_read_byte_data(new_client, LM95241_REG_R_CHIP_ID) | 
|  | >= DEFAULT_REVISION)) { | 
|  | name = DEVNAME; | 
|  | } else { | 
|  | dev_dbg(&adapter->dev, "LM95241 detection failed at 0x%02x\n", | 
|  | address); | 
|  | return -ENODEV; | 
|  | } | 
|  |  | 
|  | /* Fill the i2c board info */ | 
|  | strlcpy(info->type, name, I2C_NAME_SIZE); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static void lm95241_init_client(struct i2c_client *client) | 
|  | { | 
|  | struct lm95241_data *data = i2c_get_clientdata(client); | 
|  |  | 
|  | data->interval = HZ;	/* 1 sec default */ | 
|  | data->valid = 0; | 
|  | data->config = CFG_CR0076; | 
|  | data->model = 0; | 
|  | data->trutherm = (TT_OFF << TT1_SHIFT) | (TT_OFF << TT2_SHIFT); | 
|  |  | 
|  | i2c_smbus_write_byte_data(client, LM95241_REG_RW_CONFIG, data->config); | 
|  | i2c_smbus_write_byte_data(client, LM95241_REG_RW_REM_FILTER, | 
|  | R1FE_MASK | R2FE_MASK); | 
|  | i2c_smbus_write_byte_data(client, LM95241_REG_RW_TRUTHERM, | 
|  | data->trutherm); | 
|  | i2c_smbus_write_byte_data(client, LM95241_REG_RW_REMOTE_MODEL, | 
|  | data->model); | 
|  | } | 
|  |  | 
|  | static int lm95241_probe(struct i2c_client *new_client, | 
|  | const struct i2c_device_id *id) | 
|  | { | 
|  | struct lm95241_data *data; | 
|  | int err; | 
|  |  | 
|  | data = kzalloc(sizeof(struct lm95241_data), GFP_KERNEL); | 
|  | if (!data) { | 
|  | err = -ENOMEM; | 
|  | goto exit; | 
|  | } | 
|  |  | 
|  | i2c_set_clientdata(new_client, data); | 
|  | mutex_init(&data->update_lock); | 
|  |  | 
|  | /* Initialize the LM95241 chip */ | 
|  | lm95241_init_client(new_client); | 
|  |  | 
|  | /* Register sysfs hooks */ | 
|  | err = sysfs_create_group(&new_client->dev.kobj, &lm95241_group); | 
|  | if (err) | 
|  | goto exit_free; | 
|  |  | 
|  | data->hwmon_dev = hwmon_device_register(&new_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(&new_client->dev.kobj, &lm95241_group); | 
|  | exit_free: | 
|  | kfree(data); | 
|  | exit: | 
|  | return err; | 
|  | } | 
|  |  | 
|  | static int lm95241_remove(struct i2c_client *client) | 
|  | { | 
|  | struct lm95241_data *data = i2c_get_clientdata(client); | 
|  |  | 
|  | hwmon_device_unregister(data->hwmon_dev); | 
|  | sysfs_remove_group(&client->dev.kobj, &lm95241_group); | 
|  |  | 
|  | kfree(data); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | /* Driver data (common to all clients) */ | 
|  | static const struct i2c_device_id lm95241_id[] = { | 
|  | { DEVNAME, 0 }, | 
|  | { } | 
|  | }; | 
|  | MODULE_DEVICE_TABLE(i2c, lm95241_id); | 
|  |  | 
|  | static struct i2c_driver lm95241_driver = { | 
|  | .class		= I2C_CLASS_HWMON, | 
|  | .driver = { | 
|  | .name	= DEVNAME, | 
|  | }, | 
|  | .probe		= lm95241_probe, | 
|  | .remove		= lm95241_remove, | 
|  | .id_table	= lm95241_id, | 
|  | .detect		= lm95241_detect, | 
|  | .address_list	= normal_i2c, | 
|  | }; | 
|  |  | 
|  | static int __init sensors_lm95241_init(void) | 
|  | { | 
|  | return i2c_add_driver(&lm95241_driver); | 
|  | } | 
|  |  | 
|  | static void __exit sensors_lm95241_exit(void) | 
|  | { | 
|  | i2c_del_driver(&lm95241_driver); | 
|  | } | 
|  |  | 
|  | MODULE_AUTHOR("Davide Rizzo <elpa.rizzo@gmail.com>"); | 
|  | MODULE_DESCRIPTION("LM95241 sensor driver"); | 
|  | MODULE_LICENSE("GPL"); | 
|  |  | 
|  | module_init(sensors_lm95241_init); | 
|  | module_exit(sensors_lm95241_exit); |