diff options
Diffstat (limited to 'drivers/hwmon/lm73.c')
| -rw-r--r-- | drivers/hwmon/lm73.c | 287 |
1 files changed, 287 insertions, 0 deletions
diff --git a/drivers/hwmon/lm73.c b/drivers/hwmon/lm73.c new file mode 100644 index 000000000..9653bb870 --- /dev/null +++ b/drivers/hwmon/lm73.c @@ -0,0 +1,287 @@ +/* + * LM73 Sensor driver + * Based on LM75 + * + * Copyright (C) 2007, CenoSYS (www.cenosys.com). + * Copyright (C) 2009, Bollore telecom (www.bolloretelecom.eu). + * + * Guillaume Ligneul <guillaume.ligneul@gmail.com> + * Adrien Demarez <adrien.demarez@bolloretelecom.eu> + * Jeremy Laine <jeremy.laine@bolloretelecom.eu> + * Chris Verges <kg4ysn@gmail.com> + * + * This software program is licensed subject to the GNU General Public License + * (GPL).Version 2,June 1991, available at + * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/i2c.h> +#include <linux/hwmon.h> +#include <linux/hwmon-sysfs.h> +#include <linux/err.h> + + +/* Addresses scanned */ +static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4c, + 0x4d, 0x4e, I2C_CLIENT_END }; + +/* LM73 registers */ +#define LM73_REG_INPUT 0x00 +#define LM73_REG_CONF 0x01 +#define LM73_REG_MAX 0x02 +#define LM73_REG_MIN 0x03 +#define LM73_REG_CTRL 0x04 +#define LM73_REG_ID 0x07 + +#define LM73_ID 0x9001 /* 0x0190, byte-swapped */ +#define DRVNAME "lm73" +#define LM73_TEMP_MIN (-256000 / 250) +#define LM73_TEMP_MAX (255750 / 250) + +#define LM73_CTRL_RES_SHIFT 5 +#define LM73_CTRL_RES_MASK (BIT(5) | BIT(6)) +#define LM73_CTRL_TO_MASK BIT(7) + +#define LM73_CTRL_HI_SHIFT 2 +#define LM73_CTRL_LO_SHIFT 1 + +static const unsigned short lm73_convrates[] = { + 14, /* 11-bits (0.25000 C/LSB): RES1 Bit = 0, RES0 Bit = 0 */ + 28, /* 12-bits (0.12500 C/LSB): RES1 Bit = 0, RES0 Bit = 1 */ + 56, /* 13-bits (0.06250 C/LSB): RES1 Bit = 1, RES0 Bit = 0 */ + 112, /* 14-bits (0.03125 C/LSB): RES1 Bit = 1, RES0 Bit = 1 */ +}; + +struct lm73_data { + struct i2c_client *client; + struct mutex lock; + u8 ctrl; /* control register value */ +}; + +/*-----------------------------------------------------------------------*/ + +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 lm73_data *data = dev_get_drvdata(dev); + long temp; + short value; + s32 err; + + int status = kstrtol(buf, 10, &temp); + if (status < 0) + return status; + + /* Write value */ + value = clamp_val(temp / 250, LM73_TEMP_MIN, LM73_TEMP_MAX) << 5; + err = i2c_smbus_write_word_swapped(data->client, attr->index, value); + return (err < 0) ? err : count; +} + +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 lm73_data *data = dev_get_drvdata(dev); + int temp; + + s32 err = i2c_smbus_read_word_swapped(data->client, attr->index); + if (err < 0) + return err; + + /* use integer division instead of equivalent right shift to + guarantee arithmetic shift and preserve the sign */ + temp = (((s16) err) * 250) / 32; + return scnprintf(buf, PAGE_SIZE, "%d\n", temp); +} + +static ssize_t set_convrate(struct device *dev, struct device_attribute *da, + const char *buf, size_t count) +{ + struct lm73_data *data = dev_get_drvdata(dev); + unsigned long convrate; + s32 err; + int res = 0; + + err = kstrtoul(buf, 10, &convrate); + if (err < 0) + return err; + + /* + * Convert the desired conversion rate into register bits. + * res is already initialized, and everything past the second-to-last + * value in the array is treated as belonging to the last value + * in the array. + */ + while (res < (ARRAY_SIZE(lm73_convrates) - 1) && + convrate > lm73_convrates[res]) + res++; + + mutex_lock(&data->lock); + data->ctrl &= LM73_CTRL_TO_MASK; + data->ctrl |= res << LM73_CTRL_RES_SHIFT; + err = i2c_smbus_write_byte_data(data->client, LM73_REG_CTRL, + data->ctrl); + mutex_unlock(&data->lock); + + if (err < 0) + return err; + + return count; +} + +static ssize_t show_convrate(struct device *dev, struct device_attribute *da, + char *buf) +{ + struct lm73_data *data = dev_get_drvdata(dev); + int res; + + res = (data->ctrl & LM73_CTRL_RES_MASK) >> LM73_CTRL_RES_SHIFT; + return scnprintf(buf, PAGE_SIZE, "%hu\n", lm73_convrates[res]); +} + +static ssize_t show_maxmin_alarm(struct device *dev, + struct device_attribute *da, char *buf) +{ + struct sensor_device_attribute *attr = to_sensor_dev_attr(da); + struct lm73_data *data = dev_get_drvdata(dev); + s32 ctrl; + + mutex_lock(&data->lock); + ctrl = i2c_smbus_read_byte_data(data->client, LM73_REG_CTRL); + if (ctrl < 0) + goto abort; + data->ctrl = ctrl; + mutex_unlock(&data->lock); + + return scnprintf(buf, PAGE_SIZE, "%d\n", (ctrl >> attr->index) & 1); + +abort: + mutex_unlock(&data->lock); + return ctrl; +} + +/*-----------------------------------------------------------------------*/ + +/* sysfs attributes for hwmon */ + +static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, + show_temp, set_temp, LM73_REG_MAX); +static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, + show_temp, set_temp, LM73_REG_MIN); +static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, + show_temp, NULL, LM73_REG_INPUT); +static SENSOR_DEVICE_ATTR(update_interval, S_IWUSR | S_IRUGO, + show_convrate, set_convrate, 0); +static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, + show_maxmin_alarm, NULL, LM73_CTRL_HI_SHIFT); +static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, + show_maxmin_alarm, NULL, LM73_CTRL_LO_SHIFT); + +static struct attribute *lm73_attrs[] = { + &sensor_dev_attr_temp1_input.dev_attr.attr, + &sensor_dev_attr_temp1_max.dev_attr.attr, + &sensor_dev_attr_temp1_min.dev_attr.attr, + &sensor_dev_attr_update_interval.dev_attr.attr, + &sensor_dev_attr_temp1_max_alarm.dev_attr.attr, + &sensor_dev_attr_temp1_min_alarm.dev_attr.attr, + NULL +}; +ATTRIBUTE_GROUPS(lm73); + +/*-----------------------------------------------------------------------*/ + +/* device probe and removal */ + +static int +lm73_probe(struct i2c_client *client, const struct i2c_device_id *id) +{ + struct device *dev = &client->dev; + struct device *hwmon_dev; + struct lm73_data *data; + int ctrl; + + data = devm_kzalloc(dev, sizeof(struct lm73_data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->client = client; + mutex_init(&data->lock); + + ctrl = i2c_smbus_read_byte_data(client, LM73_REG_CTRL); + if (ctrl < 0) + return ctrl; + data->ctrl = ctrl; + + hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name, + data, lm73_groups); + if (IS_ERR(hwmon_dev)) + return PTR_ERR(hwmon_dev); + + dev_info(dev, "sensor '%s'\n", client->name); + + return 0; +} + +static const struct i2c_device_id lm73_ids[] = { + { "lm73", 0 }, + { /* LIST END */ } +}; +MODULE_DEVICE_TABLE(i2c, lm73_ids); + +/* Return 0 if detection is successful, -ENODEV otherwise */ +static int lm73_detect(struct i2c_client *new_client, + struct i2c_board_info *info) +{ + struct i2c_adapter *adapter = new_client->adapter; + int id, ctrl, conf; + + if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA | + I2C_FUNC_SMBUS_WORD_DATA)) + return -ENODEV; + + /* + * Do as much detection as possible with byte reads first, as word + * reads can confuse other devices. + */ + ctrl = i2c_smbus_read_byte_data(new_client, LM73_REG_CTRL); + if (ctrl < 0 || (ctrl & 0x10)) + return -ENODEV; + + conf = i2c_smbus_read_byte_data(new_client, LM73_REG_CONF); + if (conf < 0 || (conf & 0x0c)) + return -ENODEV; + + id = i2c_smbus_read_byte_data(new_client, LM73_REG_ID); + if (id < 0 || id != (LM73_ID & 0xff)) + return -ENODEV; + + /* Check device ID */ + id = i2c_smbus_read_word_data(new_client, LM73_REG_ID); + if (id < 0 || id != LM73_ID) + return -ENODEV; + + strlcpy(info->type, "lm73", I2C_NAME_SIZE); + + return 0; +} + +static struct i2c_driver lm73_driver = { + .class = I2C_CLASS_HWMON, + .driver = { + .name = "lm73", + }, + .probe = lm73_probe, + .id_table = lm73_ids, + .detect = lm73_detect, + .address_list = normal_i2c, +}; + +module_i2c_driver(lm73_driver); + +MODULE_AUTHOR("Guillaume Ligneul <guillaume.ligneul@gmail.com>"); +MODULE_DESCRIPTION("LM73 driver"); +MODULE_LICENSE("GPL"); |