diff options
Diffstat (limited to 'drivers/hwmon/lm95241.c')
| -rw-r--r-- | drivers/hwmon/lm95241.c | 424 |
1 files changed, 424 insertions, 0 deletions
diff --git a/drivers/hwmon/lm95241.c b/drivers/hwmon/lm95241.c new file mode 100644 index 000000000..cdf19adae --- /dev/null +++ b/drivers/hwmon/lm95241.c @@ -0,0 +1,424 @@ +/* + * 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 i2c_client *client; + 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 lm95241_data *data = dev_get_drvdata(dev); + struct i2c_client *client = data->client; + + mutex_lock(&data->update_lock); + + if (time_after(jiffies, data->last_updated + data->interval) || + !data->valid) { + int i; + + dev_dbg(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 lm95241_data *data = dev_get_drvdata(dev); + + 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 lm95241_data *data = dev_get_drvdata(dev); + struct i2c_client *client = data->client; + unsigned long val; + int shift; + u8 mask = to_sensor_dev_attr(attr)->index; + + if (kstrtoul(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 lm95241_data *data = dev_get_drvdata(dev); + + 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 lm95241_data *data = dev_get_drvdata(dev); + long val; + + if (kstrtol(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(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 lm95241_data *data = dev_get_drvdata(dev); + + 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 lm95241_data *data = dev_get_drvdata(dev); + long val; + + if (kstrtol(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(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 lm95241_data *data = dev_get_drvdata(dev); + unsigned long val; + + if (kstrtoul(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_attrs[] = { + &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 +}; +ATTRIBUTE_GROUPS(lm95241); + +/* 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) +{ + data->interval = HZ; /* 1 sec default */ + data->config = CFG_CR0076; + 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 *client, + const struct i2c_device_id *id) +{ + struct device *dev = &client->dev; + struct lm95241_data *data; + struct device *hwmon_dev; + + data = devm_kzalloc(dev, sizeof(struct lm95241_data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->client = client; + mutex_init(&data->update_lock); + + /* Initialize the LM95241 chip */ + lm95241_init_client(client, data); + + hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name, + data, + lm95241_groups); + return PTR_ERR_OR_ZERO(hwmon_dev); +} + +/* 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, + .id_table = lm95241_id, + .detect = lm95241_detect, + .address_list = normal_i2c, +}; + +module_i2c_driver(lm95241_driver); + +MODULE_AUTHOR("Davide Rizzo <elpa.rizzo@gmail.com>"); +MODULE_DESCRIPTION("LM95241 sensor driver"); +MODULE_LICENSE("GPL"); |