linux/drivers/i2c/chips/pca9539.c
Jean Delvare 3d63430a26 i2c: Convert the pca9539 driver to a new-style i2c driver
The new-style pca9539 driver implements the optional detect() callback
to cover the use cases of the legacy driver.

Warning: users will now have to use the force module parameter to get
the driver to attach to their device. That's not a bad thing as these
devices can't be detected anyway.

Note that this doesn't change the fact that this driver is deprecated
in favor of gpio/pca953x.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-07-16 19:30:07 +02:00

153 lines
4.0 KiB
C

/*
pca9539.c - 16-bit I/O port with interrupt and reset
Copyright (C) 2005 Ben Gardner <bgardner@wabtec.com>
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 of the License.
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/hwmon-sysfs.h>
/* Addresses to scan: none, device is not autodetected */
static const unsigned short normal_i2c[] = { I2C_CLIENT_END };
/* Insmod parameters */
I2C_CLIENT_INSMOD_1(pca9539);
enum pca9539_cmd
{
PCA9539_INPUT_0 = 0,
PCA9539_INPUT_1 = 1,
PCA9539_OUTPUT_0 = 2,
PCA9539_OUTPUT_1 = 3,
PCA9539_INVERT_0 = 4,
PCA9539_INVERT_1 = 5,
PCA9539_DIRECTION_0 = 6,
PCA9539_DIRECTION_1 = 7,
};
/* following are the sysfs callback functions */
static ssize_t pca9539_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct sensor_device_attribute *psa = to_sensor_dev_attr(attr);
struct i2c_client *client = to_i2c_client(dev);
return sprintf(buf, "%d\n", i2c_smbus_read_byte_data(client,
psa->index));
}
static ssize_t pca9539_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct sensor_device_attribute *psa = to_sensor_dev_attr(attr);
struct i2c_client *client = to_i2c_client(dev);
unsigned long val = simple_strtoul(buf, NULL, 0);
if (val > 0xff)
return -EINVAL;
i2c_smbus_write_byte_data(client, psa->index, val);
return count;
}
/* Define the device attributes */
#define PCA9539_ENTRY_RO(name, cmd_idx) \
static SENSOR_DEVICE_ATTR(name, S_IRUGO, pca9539_show, NULL, cmd_idx)
#define PCA9539_ENTRY_RW(name, cmd_idx) \
static SENSOR_DEVICE_ATTR(name, S_IRUGO | S_IWUSR, pca9539_show, \
pca9539_store, cmd_idx)
PCA9539_ENTRY_RO(input0, PCA9539_INPUT_0);
PCA9539_ENTRY_RO(input1, PCA9539_INPUT_1);
PCA9539_ENTRY_RW(output0, PCA9539_OUTPUT_0);
PCA9539_ENTRY_RW(output1, PCA9539_OUTPUT_1);
PCA9539_ENTRY_RW(invert0, PCA9539_INVERT_0);
PCA9539_ENTRY_RW(invert1, PCA9539_INVERT_1);
PCA9539_ENTRY_RW(direction0, PCA9539_DIRECTION_0);
PCA9539_ENTRY_RW(direction1, PCA9539_DIRECTION_1);
static struct attribute *pca9539_attributes[] = {
&sensor_dev_attr_input0.dev_attr.attr,
&sensor_dev_attr_input1.dev_attr.attr,
&sensor_dev_attr_output0.dev_attr.attr,
&sensor_dev_attr_output1.dev_attr.attr,
&sensor_dev_attr_invert0.dev_attr.attr,
&sensor_dev_attr_invert1.dev_attr.attr,
&sensor_dev_attr_direction0.dev_attr.attr,
&sensor_dev_attr_direction1.dev_attr.attr,
NULL
};
static struct attribute_group pca9539_defattr_group = {
.attrs = pca9539_attributes,
};
/* Return 0 if detection is successful, -ENODEV otherwise */
static int pca9539_detect(struct i2c_client *client, int kind,
struct i2c_board_info *info)
{
struct i2c_adapter *adapter = client->adapter;
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
return -ENODEV;
strlcpy(info->type, "pca9539", I2C_NAME_SIZE);
return 0;
}
static int pca9539_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
/* Register sysfs hooks */
return sysfs_create_group(&client->dev.kobj,
&pca9539_defattr_group);
}
static int pca9539_remove(struct i2c_client *client)
{
sysfs_remove_group(&client->dev.kobj, &pca9539_defattr_group);
return 0;
}
static const struct i2c_device_id pca9539_id[] = {
{ "pca9539", 0 },
{ }
};
static struct i2c_driver pca9539_driver = {
.driver = {
.name = "pca9539",
},
.probe = pca9539_probe,
.remove = pca9539_remove,
.id_table = pca9539_id,
.detect = pca9539_detect,
.address_data = &addr_data,
};
static int __init pca9539_init(void)
{
return i2c_add_driver(&pca9539_driver);
}
static void __exit pca9539_exit(void)
{
i2c_del_driver(&pca9539_driver);
}
MODULE_AUTHOR("Ben Gardner <bgardner@wabtec.com>");
MODULE_DESCRIPTION("PCA9539 driver");
MODULE_LICENSE("GPL");
module_init(pca9539_init);
module_exit(pca9539_exit);