linux/drivers/gpio/max7300.c
Wolfram Sang e952805d2d gpio: add driver for MAX7300 I2C GPIO extender
Add the MAX7300-I2C variant of the MAX7301-SPI version.  Both chips share
the same core logic, so the generic part of the in-kernel SPI-driver is
refactored into a generic part.  The I2C and SPI specific funtions are
then wrapped into seperate drivers picking up the generic part.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: Juergen Beisert <j.beisert@pengutronix.de>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Anton Vorontsov <avorontsov@ru.mvista.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06 11:26:48 -08:00

94 lines
2 KiB
C

/*
* drivers/gpio/max7300.c
*
* Copyright (C) 2009 Wolfram Sang, 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.
*
* Check max730x.c for further details.
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/mutex.h>
#include <linux/i2c.h>
#include <linux/spi/max7301.h>
static int max7300_i2c_write(struct device *dev, unsigned int reg,
unsigned int val)
{
struct i2c_client *client = to_i2c_client(dev);
return i2c_smbus_write_byte_data(client, reg, val);
}
static int max7300_i2c_read(struct device *dev, unsigned int reg)
{
struct i2c_client *client = to_i2c_client(dev);
return i2c_smbus_read_byte_data(client, reg);
}
static int __devinit max7300_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct max7301 *ts;
int ret;
if (!i2c_check_functionality(client->adapter,
I2C_FUNC_SMBUS_BYTE_DATA))
return -EIO;
ts = kzalloc(sizeof(struct max7301), GFP_KERNEL);
if (!ts)
return -ENOMEM;
ts->read = max7300_i2c_read;
ts->write = max7300_i2c_write;
ts->dev = &client->dev;
ret = __max730x_probe(ts);
if (ret)
kfree(ts);
return ret;
}
static int __devexit max7300_remove(struct i2c_client *client)
{
return __max730x_remove(&client->dev);
}
static const struct i2c_device_id max7300_id[] = {
{ "max7300", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, max7300_id);
static struct i2c_driver max7300_driver = {
.driver = {
.name = "max7300",
.owner = THIS_MODULE,
},
.probe = max7300_probe,
.remove = __devexit_p(max7300_remove),
.id_table = max7300_id,
};
static int __init max7300_init(void)
{
return i2c_add_driver(&max7300_driver);
}
subsys_initcall(max7300_init);
static void __exit max7300_exit(void)
{
i2c_del_driver(&max7300_driver);
}
module_exit(max7300_exit);
MODULE_AUTHOR("Wolfram Sang");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("MAX7300 GPIO-Expander");