[linux-yocto] [PATCH 15/42] drivers/hwmon: Changes to suppor the axxia BSP

[Cristian Bercaru]

From: Charlie Paul <cpaul.windriver at gmail.com>

Driver changes to hwmon to support the AXXIA 5500 board.

Signed-off-by: Charlie Paul <cpaul.windriver at gmail.com>
---
 drivers/hwmon/adt75.c |  211 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 211 insertions(+)
 create mode 100644 drivers/hwmon/adt75.c

diff --git a/drivers/hwmon/adt75.c b/drivers/hwmon/adt75.c
new file mode 100644
index 0000000..90d406c
--- /dev/null
+++ b/drivers/hwmon/adt75.c
@@ -0,0 +1,211 @@
+/*
+ * An hwmon driver for the Analog Devices ADT75
+ *
+ * Based on ad7418.c
+ * Copyright (C) 2006-07 Tower Technologies
+ *
+ * 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 - version 2.
+ */
+
+#include <linux/module.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>
+#include <linux/slab.h>
+
+#include "lm75.h"
+
+#define DRV_VERSION "0.1"
+
+/* ADT75 registers */
+#define ADT75_REG_TEMP_IN	0x00
+#define ADT75_REG_CONF		0x01
+#define ADT75_REG_TEMP_HYST	0x02
+#define ADT75_REG_TEMP_OS	0x03
+
+static const u8 ADT75_REG_TEMP[] = { ADT75_REG_TEMP_IN,
+					ADT75_REG_TEMP_HYST,
+					ADT75_REG_TEMP_OS };
+
+struct adt75_data {
+	struct device		*hwmon_dev;
+	struct attribute_group	attrs;
+	struct mutex		lock;
+	char			valid;
+	unsigned long		last_updated;	/* In jiffies */
+	s16			temp[3];	/* Register values */
+};
+
+static int adt75_probe(struct i2c_client *client,
+			const struct i2c_device_id *id);
+static int adt75_remove(struct i2c_client *client);
+
+static const struct i2c_device_id adt75_id[] = {
+	{ "adt75", },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, adt75_id);
+
+static struct i2c_driver adt75_driver = {
+	.driver = {
+		.name	= "adt75",
+	},
+	.probe		= adt75_probe,
+	.remove		= adt75_remove,
+	.id_table	= adt75_id,
+};
+
+static inline int adt75_read(struct i2c_client *client, u8 reg)
+{
+	return i2c_smbus_read_word_data(client, reg);
+}
+
+static inline int adt75_write(struct i2c_client *client, u8 reg, u16 value)
+{
+	return i2c_smbus_write_word_data(client, reg, value);
+}
+
+static void adt75_init_client(struct i2c_client *client)
+{
+	int ret = adt75_write(client, ADT75_REG_CONF, 0x0000);
+	if (ret < 0)
+		dev_err(&client->dev, "cannot write configuration register\n");
+}
+
+static struct adt75_data *adt75_update_device(struct device *dev)
+{
+	int i;
+	struct i2c_client *client = to_i2c_client(dev);
+	struct adt75_data *data = i2c_get_clientdata(client);
+
+	mutex_lock(&data->lock);
+
+	if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
+	    || !data->valid) {
+
+		for (i = 0; i < 3; i++)
+			data->temp[i] = adt75_read(client, ADT75_REG_TEMP[i]);
+
+		data->last_updated = jiffies;
+		data->valid = 1;
+	}
+
+	mutex_unlock(&data->lock);
+
+	return data;
+}
+
+static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
+			char *buf)
+{
+	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+	struct adt75_data *data = adt75_update_device(dev);
+	return sprintf(buf, "%d\n",
+		LM75_TEMP_FROM_REG(data->temp[attr->index]));
+}
+
+static ssize_t set_temp(struct device *dev, struct device_attribute *devattr,
+			const char *buf, size_t count)
+{
+	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+	struct i2c_client *client = to_i2c_client(dev);
+	struct adt75_data *data = i2c_get_clientdata(client);
+	long temp = simple_strtol(buf, NULL, 10);
+
+	mutex_lock(&data->lock);
+	data->temp[attr->index] = LM75_TEMP_TO_REG(temp);
+	adt75_write(client,
+		    ADT75_REG_TEMP[attr->index],
+		    data->temp[attr->index]);
+	mutex_unlock(&data->lock);
+	return count;
+}
+
+static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
+static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO,
+				show_temp, set_temp, 1);
+static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,
+				show_temp, set_temp, 2);
+
+static struct attribute *adt75_attributes[] = {
+	&sensor_dev_attr_temp1_max.dev_attr.attr,
+	&sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
+	&sensor_dev_attr_temp1_input.dev_attr.attr,
+	NULL
+};
+
+static int adt75_probe(struct i2c_client *client,
+			 const struct i2c_device_id *id)
+{
+	struct adt75_data *data;
+	int err;
+
+	data = kzalloc(sizeof(struct adt75_data), GFP_KERNEL);
+	if (!data) {
+		err = -ENOMEM;
+		goto exit;
+	}
+
+	i2c_set_clientdata(client, data);
+
+	mutex_init(&data->lock);
+	data->attrs.attrs = adt75_attributes;
+
+	dev_info(&client->dev, "%s chip found\n", client->name);
+
+	/* Initialize the ADT75 chip */
+	adt75_init_client(client);
+
+	/* Register sysfs hooks */
+	err = sysfs_create_group(&client->dev.kobj, &data->attrs);
+	if (err)
+		goto exit_free;
+
+	data->hwmon_dev = hwmon_device_register(&client->dev);
+	if (IS_ERR(data->hwmon_dev)) {
+		err = PTR_ERR(data->hwmon_dev);
+		goto exit_remove;
+	}
+
+	return 0;
+
+exit_remove:
+	sysfs_remove_group(&client->dev.kobj, &data->attrs);
+exit_free:
+	kfree(data);
+exit:
+	return err;
+}
+
+static int adt75_remove(struct i2c_client *client)
+{
+	struct adt75_data *data = i2c_get_clientdata(client);
+	hwmon_device_unregister(data->hwmon_dev);
+	sysfs_remove_group(&client->dev.kobj, &data->attrs);
+	kfree(data);
+	return 0;
+}
+
+static int __init adt75_init(void)
+{
+	return i2c_add_driver(&adt75_driver);
+}
+
+static void __exit adt75_exit(void)
+{
+	i2c_del_driver(&adt75_driver);
+}
+
+MODULE_AUTHOR("Alessandro Zummo <a.zummo at towertech.it>");
+MODULE_DESCRIPTION("ADT75 driver");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(DRV_VERSION);
+
+module_init(adt75_init);
+module_exit(adt75_exit);
-- 
1.7.9.5