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linux/drivers/hwmon/adt7411.c
Wolfram Sang fbae3fb154 i2c: Remove all i2c_set_clientdata(client, NULL) in drivers 
I2C drivers can use the clientdata-pointer to point to private data. As I2C
devices are not really unregistered, but merely detached from their driver, it
used to be the drivers obligation to clear this pointer during remove() or a
failed probe(). As a couple of drivers forgot to do this, it was agreed that it
was cleaner if the i2c-core does this clearance when appropriate, as there is
no guarantee for the lifetime of the clientdata-pointer after remove() anyhow.
This feature was added to the core with commit
e4a7b9b04d to fix the faulty drivers.

As there is no need anymore to clear the clientdata-pointer, remove all current
occurrences in the drivers to simplify the code and prevent confusion.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Richard Purdie <rpurdie@linux.intel.com>
Acked-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-06-03 11:33:58 +02:00

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/*
* 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 },
{ }
};
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");
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