hwmon: Driver for ADT7410
This patch brings basic support for the Analog Devices ADT7410 temperature
sensor. The following functionality has been implemented:
* get current temperature
* get/set minimum, maximum and critical temperature
* get/set hysteresis
* get alarm events for minimum, maximum and critical temperature
All implemented sysfs attributes have been sucessfully tested at temperatures
of 15°C to 40°C.
Signed-off-by: Hartmut Knaack <knaack.h@gmx.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
diff --git a/drivers/hwmon/adt7410.c b/drivers/hwmon/adt7410.c
new file mode 100644
index 0000000..f8606df
--- /dev/null
+++ b/drivers/hwmon/adt7410.c
@@ -0,0 +1,459 @@
+/*
+ * adt7410.c - Part of lm_sensors, Linux kernel modules for hardware
+ * monitoring
+ * This driver handles the ADT7410 and compatible digital temperature sensors.
+ * Hartmut Knaack <knaack.h@gmx.de> 2012-07-22
+ * based on lm75.c by Frodo Looijaard <frodol@dds.nl>
+ * and adt7410.c from iio-staging by Sonic Zhang <sonic.zhang@analog.com>
+ *
+ * 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/delay.h>
+
+/*
+ * ADT7410 registers definition
+ */
+
+#define ADT7410_TEMPERATURE 0
+#define ADT7410_STATUS 2
+#define ADT7410_CONFIG 3
+#define ADT7410_T_ALARM_HIGH 4
+#define ADT7410_T_ALARM_LOW 6
+#define ADT7410_T_CRIT 8
+#define ADT7410_T_HYST 0xA
+
+/*
+ * ADT7410 status
+ */
+#define ADT7410_STAT_T_LOW (1 << 4)
+#define ADT7410_STAT_T_HIGH (1 << 5)
+#define ADT7410_STAT_T_CRIT (1 << 6)
+#define ADT7410_STAT_NOT_RDY (1 << 7)
+
+/*
+ * ADT7410 config
+ */
+#define ADT7410_FAULT_QUEUE_MASK (1 << 0 | 1 << 1)
+#define ADT7410_CT_POLARITY (1 << 2)
+#define ADT7410_INT_POLARITY (1 << 3)
+#define ADT7410_EVENT_MODE (1 << 4)
+#define ADT7410_MODE_MASK (1 << 5 | 1 << 6)
+#define ADT7410_FULL (0 << 5 | 0 << 6)
+#define ADT7410_PD (1 << 5 | 1 << 6)
+#define ADT7410_RESOLUTION (1 << 7)
+
+/*
+ * ADT7410 masks
+ */
+#define ADT7410_T13_VALUE_MASK 0xFFF8
+#define ADT7410_T_HYST_MASK 0xF
+
+/* straight from the datasheet */
+#define ADT7410_TEMP_MIN (-55000)
+#define ADT7410_TEMP_MAX 150000
+
+enum adt7410_type { /* keep sorted in alphabetical order */
+ adt7410,
+};
+
+/* Addresses scanned */
+static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b,
+ I2C_CLIENT_END };
+
+static const u8 ADT7410_REG_TEMP[4] = {
+ ADT7410_TEMPERATURE, /* input */
+ ADT7410_T_ALARM_HIGH, /* high */
+ ADT7410_T_ALARM_LOW, /* low */
+ ADT7410_T_CRIT, /* critical */
+};
+
+/* Each client has this additional data */
+struct adt7410_data {
+ struct device *hwmon_dev;
+ struct mutex update_lock;
+ u8 config;
+ u8 oldconfig;
+ bool valid; /* true if registers valid */
+ unsigned long last_updated; /* In jiffies */
+ s16 temp[4]; /* Register values,
+ 0 = input
+ 1 = high
+ 2 = low
+ 3 = critical */
+ u8 hyst; /* hysteresis offset */
+};
+
+/*
+ * adt7410 register access by I2C
+ */
+static int adt7410_temp_ready(struct i2c_client *client)
+{
+ int i, status;
+
+ for (i = 0; i < 6; i++) {
+ status = i2c_smbus_read_byte_data(client, ADT7410_STATUS);
+ if (status < 0)
+ return status;
+ if (!(status & ADT7410_STAT_NOT_RDY))
+ return 0;
+ msleep(60);
+ }
+ return -ETIMEDOUT;
+}
+
+static struct adt7410_data *adt7410_update_device(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct adt7410_data *data = i2c_get_clientdata(client);
+ struct adt7410_data *ret = data;
+ mutex_lock(&data->update_lock);
+
+ if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
+ || !data->valid) {
+ int i, status;
+
+ dev_dbg(&client->dev, "Starting update\n");
+
+ status = adt7410_temp_ready(client); /* check for new value */
+ if (unlikely(status)) {
+ ret = ERR_PTR(status);
+ goto abort;
+ }
+ for (i = 0; i < ARRAY_SIZE(data->temp); i++) {
+ status = i2c_smbus_read_word_swapped(client,
+ ADT7410_REG_TEMP[i]);
+ if (unlikely(status < 0)) {
+ dev_dbg(dev,
+ "Failed to read value: reg %d, error %d\n",
+ ADT7410_REG_TEMP[i], status);
+ ret = ERR_PTR(status);
+ goto abort;
+ }
+ data->temp[i] = status;
+ }
+ status = i2c_smbus_read_byte_data(client, ADT7410_T_HYST);
+ if (unlikely(status < 0)) {
+ dev_dbg(dev,
+ "Failed to read value: reg %d, error %d\n",
+ ADT7410_T_HYST, status);
+ ret = ERR_PTR(status);
+ goto abort;
+ }
+ data->hyst = status;
+ data->last_updated = jiffies;
+ data->valid = true;
+ }
+
+abort:
+ mutex_unlock(&data->update_lock);
+ return ret;
+}
+
+static s16 ADT7410_TEMP_TO_REG(long temp)
+{
+ return DIV_ROUND_CLOSEST(SENSORS_LIMIT(temp, ADT7410_TEMP_MIN,
+ ADT7410_TEMP_MAX) * 128, 1000);
+}
+
+static int ADT7410_REG_TO_TEMP(struct adt7410_data *data, s16 reg)
+{
+ /* in 13 bit mode, bits 0-2 are status flags - mask them out */
+ if (!(data->config & ADT7410_RESOLUTION))
+ reg &= ADT7410_T13_VALUE_MASK;
+ /*
+ * temperature is stored in twos complement format, in steps of
+ * 1/128°C
+ */
+ return DIV_ROUND_CLOSEST(reg * 1000, 128);
+}
+
+/*-----------------------------------------------------------------------*/
+
+/* sysfs attributes for hwmon */
+
+static ssize_t adt7410_show_temp(struct device *dev,
+ struct device_attribute *da, char *buf)
+{
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+ struct adt7410_data *data = adt7410_update_device(dev);
+
+ if (IS_ERR(data))
+ return PTR_ERR(data);
+
+ return sprintf(buf, "%d\n", ADT7410_REG_TO_TEMP(data,
+ data->temp[attr->index]));
+}
+
+static ssize_t adt7410_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 adt7410_data *data = i2c_get_clientdata(client);
+ int nr = attr->index;
+ long temp;
+ int ret;
+
+ ret = kstrtol(buf, 10, &temp);
+ if (ret)
+ return ret;
+
+ mutex_lock(&data->update_lock);
+ data->temp[nr] = ADT7410_TEMP_TO_REG(temp);
+ ret = i2c_smbus_write_word_swapped(client, ADT7410_REG_TEMP[nr],
+ data->temp[nr]);
+ if (ret)
+ count = ret;
+ mutex_unlock(&data->update_lock);
+ return count;
+}
+
+static ssize_t adt7410_show_t_hyst(struct device *dev,
+ struct device_attribute *da,
+ char *buf)
+{
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+ struct adt7410_data *data = adt7410_update_device(dev);
+ int nr = attr->index;
+ int hyst = (data->hyst & ADT7410_T_HYST_MASK) * 1000;
+
+ /*
+ * hysteresis is stored as a 4 bit offset in the device, convert it
+ * to an absolute value
+ */
+ if (nr == 2) /* min has positive offset, others have negative */
+ hyst = -hyst;
+ return sprintf(buf, "%d\n",
+ ADT7410_REG_TO_TEMP(data, data->temp[nr]) - hyst);
+}
+
+static ssize_t adt7410_set_t_hyst(struct device *dev,
+ struct device_attribute *da,
+ const char *buf, size_t count)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct adt7410_data *data = i2c_get_clientdata(client);
+ int limit, ret;
+ long hyst;
+
+ ret = kstrtol(buf, 10, &hyst);
+ if (ret)
+ return ret;
+ /* convert absolute hysteresis value to a 4 bit delta value */
+ limit = ADT7410_REG_TO_TEMP(data, data->temp[1]);
+ hyst = SENSORS_LIMIT(hyst, ADT7410_TEMP_MIN, ADT7410_TEMP_MAX);
+ data->hyst = SENSORS_LIMIT(DIV_ROUND_CLOSEST(limit - hyst, 1000),
+ 0, ADT7410_T_HYST_MASK);
+ ret = i2c_smbus_write_byte_data(client, ADT7410_T_HYST, data->hyst);
+ if (ret)
+ return ret;
+
+ return count;
+}
+
+static ssize_t adt7410_show_alarm(struct device *dev,
+ struct device_attribute *da,
+ char *buf)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+ int ret;
+
+ ret = i2c_smbus_read_byte_data(client, ADT7410_STATUS);
+ if (ret < 0)
+ return ret;
+
+ return sprintf(buf, "%d\n", !!(ret & attr->index));
+}
+
+static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, adt7410_show_temp, NULL, 0);
+static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,
+ adt7410_show_temp, adt7410_set_temp, 1);
+static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO,
+ adt7410_show_temp, adt7410_set_temp, 2);
+static SENSOR_DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO,
+ adt7410_show_temp, adt7410_set_temp, 3);
+static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO,
+ adt7410_show_t_hyst, adt7410_set_t_hyst, 1);
+static SENSOR_DEVICE_ATTR(temp1_min_hyst, S_IRUGO,
+ adt7410_show_t_hyst, NULL, 2);
+static SENSOR_DEVICE_ATTR(temp1_crit_hyst, S_IRUGO,
+ adt7410_show_t_hyst, NULL, 3);
+static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, adt7410_show_alarm,
+ NULL, ADT7410_STAT_T_LOW);
+static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, adt7410_show_alarm,
+ NULL, ADT7410_STAT_T_HIGH);
+static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, adt7410_show_alarm,
+ NULL, ADT7410_STAT_T_CRIT);
+
+static struct attribute *adt7410_attributes[] = {
+ &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_temp1_crit.dev_attr.attr,
+ &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
+ &sensor_dev_attr_temp1_min_hyst.dev_attr.attr,
+ &sensor_dev_attr_temp1_crit_hyst.dev_attr.attr,
+ &sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
+ &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
+ &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
+ NULL
+};
+
+static const struct attribute_group adt7410_group = {
+ .attrs = adt7410_attributes,
+};
+
+/*-----------------------------------------------------------------------*/
+
+/* device probe and removal */
+
+static int adt7410_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct adt7410_data *data;
+ int ret;
+
+ if (!i2c_check_functionality(client->adapter,
+ I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA))
+ return -ENODEV;
+
+ data = devm_kzalloc(&client->dev, sizeof(struct adt7410_data),
+ GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ i2c_set_clientdata(client, data);
+ mutex_init(&data->update_lock);
+
+ /* configure as specified */
+ ret = i2c_smbus_read_byte_data(client, ADT7410_CONFIG);
+ if (ret < 0) {
+ dev_dbg(&client->dev, "Can't read config? %d\n", ret);
+ return ret;
+ }
+ data->oldconfig = ret;
+ /*
+ * Set to 16 bit resolution, continous conversion and comparator mode.
+ */
+ data->config = ret | ADT7410_FULL | ADT7410_RESOLUTION |
+ ADT7410_EVENT_MODE;
+ if (data->config != data->oldconfig) {
+ ret = i2c_smbus_write_byte_data(client, ADT7410_CONFIG,
+ data->config);
+ if (ret)
+ return ret;
+ }
+ dev_dbg(&client->dev, "Config %02x\n", data->config);
+
+ /* Register sysfs hooks */
+ ret = sysfs_create_group(&client->dev.kobj, &adt7410_group);
+ if (ret)
+ goto exit_restore;
+
+ data->hwmon_dev = hwmon_device_register(&client->dev);
+ if (IS_ERR(data->hwmon_dev)) {
+ ret = PTR_ERR(data->hwmon_dev);
+ goto exit_remove;
+ }
+
+ dev_info(&client->dev, "sensor '%s'\n", client->name);
+
+ return 0;
+
+exit_remove:
+ sysfs_remove_group(&client->dev.kobj, &adt7410_group);
+exit_restore:
+ i2c_smbus_write_byte_data(client, ADT7410_CONFIG, data->oldconfig);
+ return ret;
+}
+
+static int adt7410_remove(struct i2c_client *client)
+{
+ struct adt7410_data *data = i2c_get_clientdata(client);
+
+ hwmon_device_unregister(data->hwmon_dev);
+ sysfs_remove_group(&client->dev.kobj, &adt7410_group);
+ if (data->oldconfig != data->config)
+ i2c_smbus_write_byte_data(client, ADT7410_CONFIG,
+ data->oldconfig);
+ return 0;
+}
+
+static const struct i2c_device_id adt7410_ids[] = {
+ { "adt7410", adt7410, },
+ { /* LIST END */ }
+};
+MODULE_DEVICE_TABLE(i2c, adt7410_ids);
+
+#ifdef CONFIG_PM
+static int adt7410_suspend(struct device *dev)
+{
+ int ret;
+ struct i2c_client *client = to_i2c_client(dev);
+ struct adt7410_data *data = i2c_get_clientdata(client);
+
+ ret = i2c_smbus_write_byte_data(client, ADT7410_CONFIG,
+ data->config | ADT7410_PD);
+ return ret;
+}
+
+static int adt7410_resume(struct device *dev)
+{
+ int ret;
+ struct i2c_client *client = to_i2c_client(dev);
+ struct adt7410_data *data = i2c_get_clientdata(client);
+
+ ret = i2c_smbus_write_byte_data(client, ADT7410_CONFIG, data->config);
+ return ret;
+}
+
+static const struct dev_pm_ops adt7410_dev_pm_ops = {
+ .suspend = adt7410_suspend,
+ .resume = adt7410_resume,
+};
+#define ADT7410_DEV_PM_OPS (&adt7410_dev_pm_ops)
+#else
+#define ADT7410_DEV_PM_OPS NULL
+#endif /* CONFIG_PM */
+
+static struct i2c_driver adt7410_driver = {
+ .class = I2C_CLASS_HWMON,
+ .driver = {
+ .name = "adt7410",
+ .pm = ADT7410_DEV_PM_OPS,
+ },
+ .probe = adt7410_probe,
+ .remove = adt7410_remove,
+ .id_table = adt7410_ids,
+ .address_list = normal_i2c,
+};
+
+module_i2c_driver(adt7410_driver);
+
+MODULE_AUTHOR("Hartmut Knaack");
+MODULE_DESCRIPTION("ADT7410 driver");
+MODULE_LICENSE("GPL");