linux-sg2042/drivers/mfd/tps65912-i2c.c

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/*
* tps65912-i2c.c -- I2C access for TI TPS65912x PMIC
*
* Copyright 2011 Texas Instruments Inc.
*
* Author: Margarita Olaya Cabrera <magi@slimlogic.co.uk>
*
* 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; either version 2 of the License, or (at your
* option) any later version.
*
* This driver is based on wm8350 implementation.
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/gpio.h>
#include <linux/i2c.h>
#include <linux/mfd/core.h>
#include <linux/mfd/tps65912.h>
static int tps65912_i2c_read(struct tps65912 *tps65912, u8 reg,
int bytes, void *dest)
{
struct i2c_client *i2c = tps65912->control_data;
struct i2c_msg xfer[2];
int ret;
/* Write register */
xfer[0].addr = i2c->addr;
xfer[0].flags = 0;
xfer[0].len = 1;
xfer[0].buf = &reg;
/* Read data */
xfer[1].addr = i2c->addr;
xfer[1].flags = I2C_M_RD;
xfer[1].len = bytes;
xfer[1].buf = dest;
ret = i2c_transfer(i2c->adapter, xfer, 2);
if (ret == 2)
ret = 0;
else if (ret >= 0)
ret = -EIO;
return ret;
}
static int tps65912_i2c_write(struct tps65912 *tps65912, u8 reg,
int bytes, void *src)
{
struct i2c_client *i2c = tps65912->control_data;
/* we add 1 byte for device register */
u8 msg[TPS6591X_MAX_REGISTER + 1];
int ret;
if (bytes > TPS6591X_MAX_REGISTER)
return -EINVAL;
msg[0] = reg;
memcpy(&msg[1], src, bytes);
ret = i2c_master_send(i2c, msg, bytes + 1);
if (ret < 0)
return ret;
if (ret != bytes + 1)
return -EIO;
return 0;
}
static int tps65912_i2c_probe(struct i2c_client *i2c,
const struct i2c_device_id *id)
{
struct tps65912 *tps65912;
tps65912 = devm_kzalloc(&i2c->dev,
sizeof(struct tps65912), GFP_KERNEL);
if (tps65912 == NULL)
return -ENOMEM;
i2c_set_clientdata(i2c, tps65912);
tps65912->dev = &i2c->dev;
tps65912->control_data = i2c;
tps65912->read = tps65912_i2c_read;
tps65912->write = tps65912_i2c_write;
return tps65912_device_init(tps65912);
}
static int tps65912_i2c_remove(struct i2c_client *i2c)
{
struct tps65912 *tps65912 = i2c_get_clientdata(i2c);
tps65912_device_exit(tps65912);
return 0;
}
static const struct i2c_device_id tps65912_i2c_id[] = {
{"tps65912", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, tps65912_i2c_id);
static struct i2c_driver tps65912_i2c_driver = {
.driver = {
.name = "tps65912",
.owner = THIS_MODULE,
},
.probe = tps65912_i2c_probe,
.remove = tps65912_i2c_remove,
.id_table = tps65912_i2c_id,
};
static int __init tps65912_i2c_init(void)
{
int ret;
ret = i2c_add_driver(&tps65912_i2c_driver);
if (ret != 0)
pr_err("Failed to register TPS65912 I2C driver: %d\n", ret);
return ret;
}
/* init early so consumer devices can complete system boot */
subsys_initcall(tps65912_i2c_init);
static void __exit tps65912_i2c_exit(void)
{
i2c_del_driver(&tps65912_i2c_driver);
}
module_exit(tps65912_i2c_exit);
MODULE_AUTHOR("Margarita Olaya <magi@slimlogic.co.uk>");
MODULE_DESCRIPTION("TPS6591x chip family multi-function driver");
MODULE_LICENSE("GPL");