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/*
* I2C driver for Maxim MAX8925
*
* Copyright (C) 2009 Marvell International Ltd.
* Haojian Zhuang <haojian.zhuang@marvell.com>
*
* 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.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/i2c.h>
#include <linux/mfd/max8925.h>
static inline int max8925_read_device(struct i2c_client *i2c,
int reg, int bytes, void *dest)
{
unsigned char data;
unsigned char *buf;
int ret;
buf = kzalloc(bytes + 1, GFP_KERNEL);
if (!buf)
return -ENOMEM;
data = (unsigned char)reg;
ret = i2c_master_send(i2c, &data, 1);
if (ret < 0)
return ret;
ret = i2c_master_recv(i2c, buf, bytes + 1);
if (ret < 0)
return ret;
memcpy(dest, buf, bytes);
return 0;
}
static inline int max8925_write_device(struct i2c_client *i2c,
int reg, int bytes, void *src)
{
unsigned char buf[bytes + 1];
int ret;
buf[0] = (unsigned char)reg;
memcpy(&buf[1], src, bytes);
ret = i2c_master_send(i2c, buf, bytes + 1);
if (ret < 0)
return ret;
return 0;
}
int max8925_reg_read(struct i2c_client *i2c, int reg)
{
struct max8925_chip *chip = i2c_get_clientdata(i2c);
unsigned char data;
int ret;
mutex_lock(&chip->io_lock);
ret = max8925_read_device(i2c, reg, 1, &data);
mutex_unlock(&chip->io_lock);
if (ret < 0)
return ret;
else
return (int)data;
}
EXPORT_SYMBOL(max8925_reg_read);
int max8925_reg_write(struct i2c_client *i2c, int reg,
unsigned char data)
{
struct max8925_chip *chip = i2c_get_clientdata(i2c);
int ret;
mutex_lock(&chip->io_lock);
ret = max8925_write_device(i2c, reg, 1, &data);
mutex_unlock(&chip->io_lock);
return ret;
}
EXPORT_SYMBOL(max8925_reg_write);
int max8925_bulk_read(struct i2c_client *i2c, int reg,
int count, unsigned char *buf)
{
struct max8925_chip *chip = i2c_get_clientdata(i2c);
int ret;
mutex_lock(&chip->io_lock);
ret = max8925_read_device(i2c, reg, count, buf);
mutex_unlock(&chip->io_lock);
return ret;
}
EXPORT_SYMBOL(max8925_bulk_read);
int max8925_bulk_write(struct i2c_client *i2c, int reg,
int count, unsigned char *buf)
{
struct max8925_chip *chip = i2c_get_clientdata(i2c);
int ret;
mutex_lock(&chip->io_lock);
ret = max8925_write_device(i2c, reg, count, buf);
mutex_unlock(&chip->io_lock);
return ret;
}
EXPORT_SYMBOL(max8925_bulk_write);
int max8925_set_bits(struct i2c_client *i2c, int reg,
unsigned char mask, unsigned char data)
{
struct max8925_chip *chip = i2c_get_clientdata(i2c);
unsigned char value;
int ret;
mutex_lock(&chip->io_lock);
ret = max8925_read_device(i2c, reg, 1, &value);
if (ret < 0)
goto out;
value &= ~mask;
value |= data;
ret = max8925_write_device(i2c, reg, 1, &value);
out:
mutex_unlock(&chip->io_lock);
return ret;
}
EXPORT_SYMBOL(max8925_set_bits);
static const struct i2c_device_id max8925_id_table[] = {
{ "max8925", 0 },
{}
};
MODULE_DEVICE_TABLE(i2c, max8925_id_table);
static int __devinit max8925_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct max8925_platform_data *pdata = client->dev.platform_data;
struct max8925_chip *chip;
if (!pdata) {
pr_info("%s: platform data is missing\n", __func__);
return -EINVAL;
}
if ((pdata->chip_id <= MAX8925_INVALID)
|| (pdata->chip_id >= MAX8925_MAX)) {
pr_info("#%s: wrong chip identification\n", __func__);
return -EINVAL;
}
chip = kzalloc(sizeof(struct max8925_chip), GFP_KERNEL);
if (chip == NULL)
return -ENOMEM;
chip->i2c = client;
chip->chip_id = pdata->chip_id;
i2c_set_clientdata(client, chip);
chip->dev = &client->dev;
mutex_init(&chip->io_lock);
dev_set_drvdata(chip->dev, chip);
max8925_device_init(chip, pdata);
return 0;
}
static int __devexit max8925_remove(struct i2c_client *client)
{
struct max8925_chip *chip = i2c_get_clientdata(client);
max8925_device_exit(chip);
i2c_set_clientdata(client, NULL);
kfree(chip);
return 0;
}
static struct i2c_driver max8925_driver = {
.driver = {
.name = "max8925",
.owner = THIS_MODULE,
},
.probe = max8925_probe,
.remove = __devexit_p(max8925_remove),
.id_table = max8925_id_table,
};
static int __init max8925_i2c_init(void)
{
int ret;
ret = i2c_add_driver(&max8925_driver);
if (ret != 0)
pr_err("Failed to register MAX8925 I2C driver: %d\n", ret);
return ret;
}
subsys_initcall(max8925_i2c_init);
static void __exit max8925_i2c_exit(void)
{
i2c_del_driver(&max8925_driver);
}
module_exit(max8925_i2c_exit);
MODULE_DESCRIPTION("I2C Driver for Maxim 8925");
MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
MODULE_LICENSE("GPL");
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