/*
* An hwmon driver for the Analog Devices AD7416/17/18
* Copyright (C) 2006-07 Tower Technologies
*
* Author: Alessandro Zummo <a.zummo@towertech.it>
*
* Based on lm75.c
* Copyright (C) 1998-99 Frodo Looijaard <frodol@dds.nl>
*
* 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 "lm75.h"
#define DRV_VERSION "0.3"
/* Addresses to scan */
static unsigned short normal_i2c[] = { 0x28, I2C_CLIENT_END };
/* Insmod parameters */
I2C_CLIENT_INSMOD_3(ad7416, ad7417, ad7418);
/* AD7418 registers */
#define AD7418_REG_TEMP_IN 0x00
#define AD7418_REG_CONF 0x01
#define AD7418_REG_TEMP_HYST 0x02
#define AD7418_REG_TEMP_OS 0x03
#define AD7418_REG_ADC 0x04
#define AD7418_REG_CONF2 0x05
#define AD7418_REG_ADC_CH(x) ((x) << 5)
#define AD7418_CH_TEMP AD7418_REG_ADC_CH(0)
static const u8 AD7418_REG_TEMP[] = { AD7418_REG_TEMP_IN,
AD7418_REG_TEMP_HYST,
AD7418_REG_TEMP_OS };
struct ad7418_data {
struct i2c_client client;
struct class_device *class_dev;
struct attribute_group attrs;
enum chips type;
struct mutex lock;
int adc_max; /* number of ADC channels */
char valid;
unsigned long last_updated; /* In jiffies */
s16 temp[3]; /* Register values */
u16 in[4];
};
static int ad7418_attach_adapter(struct i2c_adapter *adapter);
static int ad7418_detect(struct i2c_adapter *adapter, int address, int kind);
static int ad7418_detach_client(struct i2c_client *client);
static struct i2c_driver ad7418_driver = {
.driver = {
.name = "ad7418",
},
.attach_adapter = ad7418_attach_adapter,
.detach_client = ad7418_detach_client,
};
/* All registers are word-sized, except for the configuration registers.
* AD7418 uses a high-byte first convention. Do NOT use those functions to
* access the configuration registers CONF and CONF2, as they are byte-sized.
*/
static inline int ad7418_read(struct i2c_client *client, u8 reg)
{
return swab16(i2c_smbus_read_word_data(client, reg));
}
static inline int ad7418_write(struct i2c_client *client, u8 reg, u16 value)
{
return i2c_smbus_write_word_data(client, reg, swab16(value));
}
static void ad7418_init_client(struct i2c_client *client)
{
struct ad7418_data *data = i2c_get_clientdata(client);
int reg = i2c_smbus_read_byte_data(client, AD7418_REG_CONF);
if (reg < 0) {
dev_err(&client->dev, "cannot read configuration register\n");
} else {
dev_info(&client->dev, "configuring for mode 1\n");
i2c_smbus_write_byte_data(client, AD7418_REG_CONF, reg & 0xfe);
if (data->type == ad7417 || data->type == ad7418)
i2c_smbus_write_byte_data(client,
AD7418_REG_CONF2, 0x00);
}
}
static struct ad7418_data *ad7418_update_device(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct ad7418_data *data = i2c_get_clientdata(client);
mutex_lock(&data->lock);
if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
|| !data->valid) {
u8 cfg;
int i, ch;
/* read config register and clear channel bits */
cfg = i2c_smbus_read_byte_data(client, AD7418_REG_CONF);
cfg &= 0x1F;
i2c_smbus_write_byte_data(client, AD7418_REG_CONF,
cfg | AD7418_CH_TEMP);
udelay(30);
for (i = 0; i < 3; i++) {
data->temp[i] = ad7418_read(client, AD7418_REG_TEMP[i]);
}
for (i = 0, ch = 4; i < data->adc_max; i++, ch--) {
i2c_smbus_write_byte_data(client,
AD7418_REG_CONF,
cfg | AD7418_REG_ADC_CH(ch));
udelay(15);
data->in[data->adc_max - 1 - i] =
ad7418_read(client, AD7418_REG_ADC);
}
/* restore old configuration value */
ad7418_write(client, AD7418_REG_CONF, cfg);
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 ad7418_data *data = ad7418_update_device(dev);
return sprintf(buf, "%d\n",
LM75_TEMP_FROM_REG(data->temp[attr->index]));
}
static ssize_t show_adc(struct device *dev, struct device_attribute *devattr,
char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
struct ad7418_data *data = ad7418_update_device(dev);
return sprintf(buf, "%d\n",
((data->in[attr->index] >> 6) * 2500 + 512) / 1024);
}
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 ad7418_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);
ad7418_write(client, AD7418_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 SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, show_adc, NULL, 0);
static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, show_adc, NULL, 1);
static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, show_adc, NULL, 2);
static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, show_adc, NULL, 3);
static int ad7418_attach_adapter(struct i2c_adapter *adapter)
{
if (!(adapter->class & I2C_CLASS_HWMON))
return 0;
return i2c_probe(adapter, &addr_data, ad7418_detect);
}
static struct attribute *ad7416_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 struct attribute *ad7417_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,
&sensor_dev_attr_in1_input.dev_attr.attr,
&sensor_dev_attr_in2_input.dev_attr.attr,
&sensor_dev_attr_in3_input.dev_attr.attr,
&sensor_dev_attr_in4_input.dev_attr.attr,
NULL
};
static struct attribute *ad7418_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,
&sensor_dev_attr_in1_input.dev_attr.attr,
NULL
};
static int ad7418_detect(struct i2c_adapter *adapter, int address, int kind)
{
struct i2c_client *client;
struct ad7418_data *data;
int err = 0;
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
I2C_FUNC_SMBUS_WORD_DATA))
goto exit;
if (!(data = kzalloc(sizeof(struct ad7418_data), GFP_KERNEL))) {
err = -ENOMEM;
goto exit;
}
client = &data->client;
client->addr = address;
client->adapter = adapter;
client->driver = &ad7418_driver;
i2c_set_clientdata(client, data);
mutex_init(&data->lock);
/* AD7418 has a curious behaviour on registers 6 and 7. They
* both always read 0xC071 and are not documented on the datasheet.
* We use them to detect the chip.
*/
if (kind <= 0) {
int reg, reg6, reg7;
/* the AD7416 lies within this address range, but I have
* no means to check.
*/
if (address >= 0x48 && address <= 0x4f) {
/* XXX add tests for AD7416 here */
/* data->type = ad7416; */
}
/* here we might have AD7417 or AD7418 */
else if (address >= 0x28 && address <= 0x2f) {
reg6 = i2c_smbus_read_word_data(client, 0x06);
reg7 = i2c_smbus_read_word_data(client, 0x07);
if (address == 0x28 && reg6 == 0xC071 && reg7 == 0xC071)
data->type = ad7418;
/* XXX add tests for AD7417 here */
/* both AD7417 and AD7418 have bits 0-5 of
* the CONF2 register at 0
*/
reg = i2c_smbus_read_byte_data(client,
AD7418_REG_CONF2);
if (reg & 0x3F)
data->type = any_chip; /* detection failed */
}
} else {
dev_dbg(&adapter->dev, "detection forced\n");
}
if (kind > 0)
data->type = kind;
else if (kind < 0 && data->type == any_chip) {
err = -ENODEV;
goto exit_free;
}
switch (data->type) {
case any_chip:
case ad7416:
data->adc_max = 0;
data->attrs.attrs = ad7416_attributes;
strlcpy(client->name, "ad7416", I2C_NAME_SIZE);
break;
case ad7417:
data->adc_max = 4;
data->attrs.attrs = ad7417_attributes;
strlcpy(client->name, "ad7417", I2C_NAME_SIZE);
break;
case ad7418:
data->adc_max = 1;
data->attrs.attrs = ad7418_attributes;
strlcpy(client->name, "ad7418", I2C_NAME_SIZE);
break;
}
if ((err = i2c_attach_client(client)))
goto exit_free;
dev_info(&client->dev, "%s chip found\n", client->name);
/* Initialize the AD7418 chip */
ad7418_init_client(client);
/* Register sysfs hooks */
if ((err = sysfs_create_group(&client->dev.kobj, &data->attrs)))
goto exit_detach;
data->class_dev = hwmon_device_register(&client->dev);
if (IS_ERR(data->class_dev)) {
err = PTR_ERR(data->class_dev);
goto exit_remove;
}
return 0;
exit_remove:
sysfs_remove_group(&client->dev.kobj, &data->attrs);
exit_detach:
i2c_detach_client(client);
exit_free:
kfree(data);
exit:
return err;
}
static int ad7418_detach_client(struct i2c_client *client)
{
struct ad7418_data *data = i2c_get_clientdata(client);
hwmon_device_unregister(data->class_dev);
sysfs_remove_group(&client->dev.kobj, &data->attrs);
i2c_detach_client(client);
kfree(data);
return 0;
}
static int __init ad7418_init(void)
{
return i2c_add_driver(&ad7418_driver);
}
static void __exit ad7418_exit(void)
{
i2c_del_driver(&ad7418_driver);
}
MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
MODULE_DESCRIPTION("AD7416/17/18 driver");
MODULE_LICENSE("GPL");
MODULE_VERSION(DRV_VERSION);
module_init(ad7418_init);
module_exit(ad7418_exit);
