This is a driver for the ad7414 temperature chip.
The driver has been through at least two reviews that I know of. It is
also in production use on the PIKA Warp Appliance.
Cheers,
Sean
Signed-off-by: Sean MacLennan <smaclennan at pikatech.com>
---
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 00ff533..3c21d57 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -57,6 +57,16 @@ config SENSORS_ABITUGURU3
This driver can also be built as a module. If so, the module
will be called abituguru3.
+config SENSORS_AD7414
+ tristate "Analog Devices AD7414"
+ depends on I2C && EXPERIMENTAL
+ help
+ If you say yes here you get support for the Analog Devices
+ AD7414 temperature monitoring chip.
+
+ This driver can also be built as a module. If so, the module
+ will be called ad7414.
+
config SENSORS_AD7418
tristate "Analog Devices AD7416, AD7417 and AD7418"
depends on I2C && EXPERIMENTAL
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index d098677..7943e5c 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -15,6 +15,7 @@ obj-$(CONFIG_SENSORS_W83791D) += w83791d.o
obj-$(CONFIG_SENSORS_ABITUGURU) += abituguru.o
obj-$(CONFIG_SENSORS_ABITUGURU3)+= abituguru3.o
+obj-$(CONFIG_SENSORS_AD7414) += ad7414.o
obj-$(CONFIG_SENSORS_AD7418) += ad7418.o
obj-$(CONFIG_SENSORS_ADM1021) += adm1021.o
obj-$(CONFIG_SENSORS_ADM1025) += adm1025.o
diff --git a/drivers/hwmon/ad7414.c b/drivers/hwmon/ad7414.c
new file mode 100644
index 0000000..e357f4f
--- /dev/null
+++ b/drivers/hwmon/ad7414.c
@@ -0,0 +1,259 @@
+/*
+ * An hwmon driver for the Analog Devices AD7414
+ *
+ * Copyright 2006 Stefan Roese <sr at denx.de>, DENX Software Engineering
+ *
+ * Copyright (c) 2008 PIKA Technologies
+ * Sean MacLennan <smaclennan at pikatech.com>
+ *
+ * Copyright (c) 2008 Spansion Inc.
+ * Frank Edelhaeuser <frank.edelhaeuser at spansion.com>
+ * (converted to "new style" I2C driver model, removed checkpatch.pl warnings)
+ *
+ * Based on ad7418.c
+ * Copyright 2006 Tower Technologies, Alessandro Zummo <a.zummo at towertech.it>
+ *
+ * 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.
+ */
+
+#include <linux/module.h>
+#include <linux/jiffies.h>
+#include <linux/i2c.h>
+#include <linux/hwmon.h>
+#include <linux/err.h>
+#include <linux/mutex.h>
+#include <linux/delay.h>
+
+
+#define DRV_VERSION "0.3"
+
+/* straight from the datasheet */
+#define AD7414_TEMP_MIN (-55000)
+#define AD7414_TEMP_MAX 125000
+
+/* AD7414 registers */
+#define AD7414_REG_TEMP 0x00
+#define AD7414_REG_CONF 0x01
+#define AD7414_REG_T_HIGH 0x02
+#define AD7414_REG_T_LOW 0x03
+
+
+struct ad7414_data {
+ struct i2c_client client;
+ struct device *dev;
+ struct mutex lock; /* atomic read data updates */
+ char valid; /* !=0 if following fields are valid */
+ unsigned long last_updated; /* In jiffies */
+ u16 temp_input; /* Register values */
+ u8 temp_max;
+ u8 temp_min;
+ u8 temp_alert;
+ u8 temp_max_flag;
+ u8 temp_min_flag;
+};
+
+/*
+ * TEMP: 0.001C/bit (-55C to +125C)
+ * REG: (0.5C/bit, two's complement) << 7
+ */
+static inline int AD7414_TEMP_FROM_REG(u16 reg)
+{
+ /* use integer division instead of equivalent right shift to
+ * guarantee arithmetic shift and preserve the sign
+ */
+ return ((s16)reg / 128) * 500;
+}
+
+/* All registers are word-sized, except for the configuration registers.
+ * AD7414 uses a high-byte first convention, which is exactly opposite to
+ * the usual practice.
+ */
+static int ad7414_read(struct i2c_client *client, u8 reg)
+{
+ if (reg == AD7414_REG_TEMP)
+ return swab16(i2c_smbus_read_word_data(client, reg));
+ else
+ return i2c_smbus_read_byte_data(client, reg);
+}
+
+static int ad7414_write(struct i2c_client *client, u8 reg, u16 value)
+{
+ return i2c_smbus_write_byte_data(client, reg, value);
+}
+
+struct ad7414_data *ad7414_update_device(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct ad7414_data *data = i2c_get_clientdata(client);
+
+ mutex_lock(&data->lock);
+
+ if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
+ || !data->valid) {
+ dev_dbg(&client->dev, "starting ad7414 update\n");
+
+ data->temp_input = ad7414_read(client, AD7414_REG_TEMP);
+ data->temp_alert = (data->temp_input >> 5) & 0x01;
+ data->temp_max_flag = (data->temp_input >> 4) & 0x01;
+ data->temp_min_flag = (data->temp_input >> 3) & 0x01;
+ data->temp_max = ad7414_read(client, AD7414_REG_T_HIGH);
+ data->temp_min = ad7414_read(client, AD7414_REG_T_LOW);
+
+ data->last_updated = jiffies;
+ data->valid = 1;
+ }
+
+ mutex_unlock(&data->lock);
+
+ return data;
+}
+
+#define show(value) \
+static ssize_t show_##value(struct device *dev, \
+ struct device_attribute *attr, char *buf) \
+{ \
+ struct ad7414_data *data = ad7414_update_device(dev); \
+ return sprintf(buf, "%d\n", AD7414_TEMP_FROM_REG(data->value)); \
+}
+show(temp_input);
+
+#define show_8(value) \
+static ssize_t show_##value(struct device *dev, \
+ struct device_attribute *attr, char *buf) \
+{ \
+ struct ad7414_data *data = ad7414_update_device(dev); \
+ return sprintf(buf, "%d\n", data->value); \
+}
+show_8(temp_max);
+show_8(temp_min);
+show_8(temp_alert);
+show_8(temp_max_flag);
+show_8(temp_min_flag);
+
+#define set(value, reg) \
+static ssize_t set_##value(struct device *dev, \
+ struct device_attribute *attr, \
+ const char *buf, size_t count) \
+{ \
+ struct i2c_client *client = to_i2c_client(dev); \
+ struct ad7414_data *data = i2c_get_clientdata(client); \
+ int temp = simple_strtoul(buf, NULL, 10); \
+ \
+ mutex_lock(&data->lock); \
+ data->value = temp; \
+ ad7414_write(client, reg, data->value); \
+ mutex_unlock(&data->lock); \
+ return count; \
+}
+set(temp_max, AD7414_REG_T_HIGH);
+set(temp_min, AD7414_REG_T_LOW);
+
+static DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp_max, set_temp_max);
+static DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, show_temp_min, set_temp_min);
+static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_input, NULL);
+static DEVICE_ATTR(temp1_alert, S_IRUGO, show_temp_alert, NULL);
+static DEVICE_ATTR(temp1_max_flag, S_IRUGO, show_temp_max_flag, NULL);
+static DEVICE_ATTR(temp1_min_flag, S_IRUGO, show_temp_min_flag, NULL);
+
+
+static struct attribute *ad7414_attributes[] = {
+ &dev_attr_temp1_input.attr,
+ &dev_attr_temp1_max.attr,
+ &dev_attr_temp1_min.attr,
+ &dev_attr_temp1_alert.attr,
+ &dev_attr_temp1_max_flag.attr,
+ &dev_attr_temp1_min_flag.attr,
+ NULL
+};
+
+static const struct attribute_group ad7414_group = {
+ .attrs = ad7414_attributes,
+};
+
+static int ad7414_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct ad7414_data *data;
+ int err = 0;
+
+ if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA |
+ I2C_FUNC_SMBUS_WORD_DATA))
+ goto exit;
+
+ data = kzalloc(sizeof(struct ad7414_data), GFP_KERNEL);
+ if (!data) {
+ err = -ENOMEM;
+ goto exit;
+ }
+
+ i2c_set_clientdata(client, data);
+ mutex_init(&data->lock);
+
+ dev_info(&client->dev, "chip found, driver version " DRV_VERSION "\n");
+
+ /* Register sysfs hooks */
+ err = sysfs_create_group(&client->dev.kobj, &ad7414_group);
+ if (err)
+ goto exit_free;
+
+ data->dev = hwmon_device_register(&client->dev);
+ if (IS_ERR(data->dev)) {
+ err = PTR_ERR(data->dev);
+ goto exit_remove;
+ }
+
+ return 0;
+
+exit_remove:
+ sysfs_remove_group(&client->dev.kobj, &ad7414_group);
+exit_free:
+ kfree(data);
+exit:
+ return err;
+}
+
+static int __devexit ad7414_remove(struct i2c_client *client)
+{
+ struct ad7414_data *data = i2c_get_clientdata(client);
+
+ hwmon_device_unregister(data->dev);
+ sysfs_remove_group(&client->dev.kobj, &ad7414_group);
+ kfree(data);
+ return 0;
+}
+
+static const struct i2c_device_id ad7414_id[] = {
+ { "ad7414", 0 },
+ {}
+};
+
+static struct i2c_driver ad7414_driver = {
+ .driver = {
+ .name = "ad7414",
+ },
+ .probe = ad7414_probe,
+ .remove = __devexit_p(ad7414_remove),
+ .id_table = ad7414_id,
+};
+
+static int __init ad7414_init(void)
+{
+ return i2c_add_driver(&ad7414_driver);
+}
+module_init(ad7414_init);
+
+static void __exit ad7414_exit(void)
+{
+ i2c_del_driver(&ad7414_driver);
+}
+module_exit(ad7414_exit);
+
+MODULE_AUTHOR("Stefan Roese <sr at denx.de>, "
+ "Frank Edelhaeuser <frank.edelhaeuser at spansion.com>");
+
+MODULE_DESCRIPTION("AD7414 driver");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(DRV_VERSION);
