- 根目录:
- drivers
- hwmon
- adt7411.c
/*
* Driver for the ADT7411 (I2C/SPI 8 channel 10 bit ADC & temperature-sensor)
*
* Copyright (C) 2008, 2010 Pengutronix
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* TODO: SPI, support for external temperature sensor
* use power-down mode for suspend?, interrupt handling?
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/delay.h>
#include <linux/mutex.h>
#include <linux/jiffies.h>
#include <linux/i2c.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/slab.h>
#define ADT7411_REG_INT_TEMP_VDD_LSB 0x03
#define ADT7411_REG_EXT_TEMP_AIN14_LSB 0x04
#define ADT7411_REG_VDD_MSB 0x06
#define ADT7411_REG_INT_TEMP_MSB 0x07
#define ADT7411_REG_EXT_TEMP_AIN1_MSB 0x08
#define ADT7411_REG_CFG1 0x18
#define ADT7411_CFG1_START_MONITOR (1 << 0)
#define ADT7411_REG_CFG2 0x19
#define ADT7411_CFG2_DISABLE_AVG (1 << 5)
#define ADT7411_REG_CFG3 0x1a
#define ADT7411_CFG3_ADC_CLK_225 (1 << 0)
#define ADT7411_CFG3_REF_VDD (1 << 4)
#define ADT7411_REG_DEVICE_ID 0x4d
#define ADT7411_REG_MANUFACTURER_ID 0x4e
#define ADT7411_DEVICE_ID 0x2
#define ADT7411_MANUFACTURER_ID 0x41
static const unsigned short normal_i2c[] = { 0x48, 0x4a, 0x4b, I2C_CLIENT_END };
struct adt7411_data {
struct mutex device_lock; /* for "atomic" device accesses */
struct mutex update_lock;
unsigned long next_update;
int vref_cached;
struct device *hwmon_dev;
};
/*
* When reading a register containing (up to 4) lsb, all associated
* msb-registers get locked by the hardware. After _one_ of those msb is read,
* _all_ are unlocked. In order to use this locking correctly, reading lsb/msb
* is protected here with a mutex, too.
*/
static int adt7411_read_10_bit(struct i2c_client *client, u8 lsb_reg,
u8 msb_reg, u8 lsb_shift)
{
struct adt7411_data *data = i2c_get_clientdata(client);
int val, tmp;
mutex_lock(&data->device_lock);
val = i2c_smbus_read_byte_data(client, lsb_reg);
if (val < 0)
goto exit_unlock;
tmp = (val >> lsb_shift) & 3;
val = i2c_smbus_read_byte_data(client, msb_reg);
if (val >= 0)
val = (val << 2) | tmp;
exit_unlock:
mutex_unlock(&data->device_lock);
return val;
}
static int adt7411_modify_bit(struct i2c_client *client, u8 reg, u8 bit,
bool flag)
{
struct adt7411_data *data = i2c_get_clientdata(client);
int ret, val;
mutex_lock(&data->device_lock);
ret = i2c_smbus_read_byte_data(client, reg);
if (ret < 0)
goto exit_unlock;
if (flag)
val = ret | bit;
else
val = ret & ~bit;
ret = i2c_smbus_write_byte_data(client, reg, val);
exit_unlock:
mutex_unlock(&data->device_lock);
return ret;
}
static ssize_t adt7411_show_vdd(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct i2c_client *client = to_i2c_client(dev);
int ret = adt7411_read_10_bit(client, ADT7411_REG_INT_TEMP_VDD_LSB,
ADT7411_REG_VDD_MSB, 2);
return ret < 0 ? ret : sprintf(buf, "%u\n", ret * 7000 / 1024);
}
static ssize_t adt7411_show_temp(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct i2c_client *client = to_i2c_client(dev);
int val = adt7411_read_10_bit(client, ADT7411_REG_INT_TEMP_VDD_LSB,
ADT7411_REG_INT_TEMP_MSB, 0);
if (val < 0)
return val;
val = val & 0x200 ? val - 0x400 : val; /* 10 bit signed */
return sprintf(buf, "%d\n", val * 250);
}
static ssize_t adt7411_show_input(struct device *dev,
struct device_attribute *attr, char *buf)
{
int nr = to_sensor_dev_attr(attr)->index;
struct i2c_client *client = to_i2c_client(dev);
struct adt7411_data *data = i2c_get_clientdata(client);
int val;
u8 lsb_reg, lsb_shift;
mutex_lock(&data->update_lock);
if (time_after_eq(jiffies, data->next_update)) {
val = i2c_smbus_read_byte_data(client, ADT7411_REG_CFG3);
if (val < 0)
goto exit_unlock;
if (val & ADT7411_CFG3_REF_VDD) {
val = adt7411_read_10_bit(client,
ADT7411_REG_INT_TEMP_VDD_LSB,
ADT7411_REG_VDD_MSB, 2);
if (val < 0)
goto exit_unlock;
data->vref_cached = val * 7000 / 1024;
} else {
data->vref_cached = 2250;
}
data->next_update = jiffies + HZ;
}
lsb_reg = ADT7411_REG_EXT_TEMP_AIN14_LSB + (nr >> 2);
lsb_shift = 2 * (nr & 0x03);
val = adt7411_read_10_bit(client, lsb_reg,
ADT7411_REG_EXT_TEMP_AIN1_MSB + nr, lsb_shift);
if (val < 0)
goto exit_unlock;
val = sprintf(buf, "%u\n", val * data->vref_cached / 1024);
exit_unlock:
mutex_unlock(&data->update_lock);
return val;
}
static ssize_t adt7411_show_bit(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct sensor_device_attribute_2 *attr2 = to_sensor_dev_attr_2(attr);
struct i2c_client *client = to_i2c_client(dev);
int ret = i2c_smbus_read_byte_data(client, attr2->index);
return ret < 0 ? ret : sprintf(buf, "%u\n", !!(ret & attr2->nr));
}
static ssize_t adt7411_set_bit(struct device *dev,
struct device_attribute *attr, const char *buf,
size_t count)
{
struct sensor_device_attribute_2 *s_attr2 = to_sensor_dev_attr_2(attr);
struct i2c_client *client = to_i2c_client(dev);
struct adt7411_data *data = i2c_get_clientdata(client);
int ret;
unsigned long flag;
ret = strict_strtoul(buf, 0, &flag);
if (ret || flag > 1)
return -EINVAL;
ret = adt7411_modify_bit(client, s_attr2->index, s_attr2->nr, flag);
/* force update */
mutex_lock(&data->update_lock);
data->next_update = jiffies;
mutex_unlock(&data->update_lock);
return ret < 0 ? ret : count;
}
#define ADT7411_BIT_ATTR(__name, __reg, __bit) \
SENSOR_DEVICE_ATTR_2(__name, S_IRUGO | S_IWUSR, adt7411_show_bit, \
adt7411_set_bit, __bit, __reg)
static DEVICE_ATTR(temp1_input, S_IRUGO, adt7411_show_temp, NULL);
static DEVICE_ATTR(in0_input, S_IRUGO, adt7411_show_vdd, NULL);
static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, adt7411_show_input, NULL, 0);
static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, adt7411_show_input, NULL, 1);
static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, adt7411_show_input, NULL, 2);
static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, adt7411_show_input, NULL, 3);
static SENSOR_DEVICE_ATTR(in5_input, S_IRUGO, adt7411_show_input, NULL, 4);
static SENSOR_DEVICE_ATTR(in6_input, S_IRUGO, adt7411_show_input, NULL, 5);
static SENSOR_DEVICE_ATTR(in7_input, S_IRUGO, adt7411_show_input, NULL, 6);
static SENSOR_DEVICE_ATTR(in8_input, S_IRUGO, adt7411_show_input, NULL, 7);
static ADT7411_BIT_ATTR(no_average, ADT7411_REG_CFG2, ADT7411_CFG2_DISABLE_AVG);
static ADT7411_BIT_ATTR(fast_sampling, ADT7411_REG_CFG3, ADT7411_CFG3_ADC_CLK_225);
static ADT7411_BIT_ATTR(adc_ref_vdd, ADT7411_REG_CFG3, ADT7411_CFG3_REF_VDD);
static struct attribute *adt7411_attrs[] = {
&dev_attr_temp1_input.attr,
&dev_attr_in0_input.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,
&sensor_dev_attr_in5_input.dev_attr.attr,
&sensor_dev_attr_in6_input.dev_attr.attr,
&sensor_dev_attr_in7_input.dev_attr.attr,
&sensor_dev_attr_in8_input.dev_attr.attr,
&sensor_dev_attr_no_average.dev_attr.attr,
&sensor_dev_attr_fast_sampling.dev_attr.attr,
&sensor_dev_attr_adc_ref_vdd.dev_attr.attr,
NULL
};
static const struct attribute_group adt7411_attr_grp = {
.attrs = adt7411_attrs,
};
static int adt7411_detect(struct i2c_client *client,
struct i2c_board_info *info)
{
int val;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
return -ENODEV;
val = i2c_smbus_read_byte_data(client, ADT7411_REG_MANUFACTURER_ID);
if (val < 0 || val != ADT7411_MANUFACTURER_ID) {
dev_dbg(&client->dev, "Wrong manufacturer ID. Got %d, "
"expected %d\n", val, ADT7411_MANUFACTURER_ID);
return -ENODEV;
}
val = i2c_smbus_read_byte_data(client, ADT7411_REG_DEVICE_ID);
if (val < 0 || val != ADT7411_DEVICE_ID) {
dev_dbg(&client->dev, "Wrong device ID. Got %d, "
"expected %d\n", val, ADT7411_DEVICE_ID);
return -ENODEV;
}
strlcpy(info->type, "adt7411", I2C_NAME_SIZE);
return 0;
}
static int __devinit adt7411_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct adt7411_data *data;
int ret;
data = kzalloc(sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
i2c_set_clientdata(client, data);
mutex_init(&data->device_lock);
mutex_init(&data->update_lock);
ret = adt7411_modify_bit(client, ADT7411_REG_CFG1,
ADT7411_CFG1_START_MONITOR, 1);
if (ret < 0)
goto exit_free;
/* force update on first occasion */
data->next_update = jiffies;
ret = sysfs_create_group(&client->dev.kobj, &adt7411_attr_grp);
if (ret)
goto exit_free;
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, "successfully registered\n");
return 0;
exit_remove:
sysfs_remove_group(&client->dev.kobj, &adt7411_attr_grp);
exit_free:
kfree(data);
return ret;
}
static int __devexit adt7411_remove(struct i2c_client *client)
{
struct adt7411_data *data = i2c_get_clientdata(client);
hwmon_device_unregister(data->hwmon_dev);
sysfs_remove_group(&client->dev.kobj, &adt7411_attr_grp);
kfree(data);
return 0;
}
static const struct i2c_device_id adt7411_id[] = {
{ "adt7411", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, adt7411_id);
static struct i2c_driver adt7411_driver = {
.driver = {
.name = "adt7411",
},
.probe = adt7411_probe,
.remove = __devexit_p(adt7411_remove),
.id_table = adt7411_id,
.detect = adt7411_detect,
.address_list = normal_i2c,
.class = I2C_CLASS_HWMON,
};
static int __init sensors_adt7411_init(void)
{
return i2c_add_driver(&adt7411_driver);
}
module_init(sensors_adt7411_init)
static void __exit sensors_adt7411_exit(void)
{
i2c_del_driver(&adt7411_driver);
}
module_exit(sensors_adt7411_exit)
MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de> and "
"Wolfram Sang <w.sang@pengutronix.de>");
MODULE_DESCRIPTION("ADT7411 driver");
MODULE_LICENSE("GPL v2");