/* * 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 NATSEMI_MAN_ID 0x01 #define LM95231_CHIP_ID 0xA1 #define LM95241_CHIP_ID 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 temp_from_reg_signed(u8 val_h, u8 val_l) { s16 val_hl = (val_h << 8) | val_l; return val_hl * 1000 / 256; } static int temp_from_reg_unsigned(u8 val_h, u8 val_l) { u16 val_hl = (val_h << 8) | val_l; return val_hl * 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); int index = to_sensor_dev_attr(attr)->index; return snprintf(buf, PAGE_SIZE - 1, "%d\n", index == 0 || (data->config & (1 << (index / 2))) ? temp_from_reg_signed(data->temp[index], data->temp[index + 1]) : temp_from_reg_unsigned(data->temp[index], data->temp[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; const char *name; int mfg_id, chip_id; if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) return -ENODEV; mfg_id = i2c_smbus_read_byte_data(new_client, LM95241_REG_R_MAN_ID); if (mfg_id != NATSEMI_MAN_ID) return -ENODEV; chip_id = i2c_smbus_read_byte_data(new_client, LM95241_REG_R_CHIP_ID); switch (chip_id) { case LM95231_CHIP_ID: name = "lm95231"; break; case LM95241_CHIP_ID: name = "lm95241"; break; default: 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[] = { { "lm95231", 0 }, { "lm95241", 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);