/*
* wm831x-i2c.c -- I2C access for Wolfson WM831x PMICs
*
* Copyright 2009,2010 Wolfson Microelectronics PLC.
*
* Author: Mark Brown <broonie@opensource.wolfsonmicro.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; either version 2 of the License, or (at your
* option) any later version.
*
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/delay.h>
#include <linux/mfd/core.h>
#include <linux/slab.h>
#include <linux/mfd/wm831x/core.h>
#include <linux/mfd/wm831x/pdata.h>
static int wm831x_i2c_read_device(struct wm831x *wm831x, unsigned short reg,
int bytes, void *dest)
{
struct i2c_client *i2c = wm831x->control_data;
int ret;
u16 r = cpu_to_be16(reg);
ret = i2c_master_send(i2c, (unsigned char *)&r, 2);
if (ret < 0)
return ret;
if (ret != 2)
return -EIO;
ret = i2c_master_recv(i2c, dest, bytes);
if (ret < 0)
return ret;
if (ret != bytes)
return -EIO;
return 0;
}
/* Currently we allocate the write buffer on the stack; this is OK for
* small writes - if we need to do large writes this will need to be
* revised.
*/
static int wm831x_i2c_write_device(struct wm831x *wm831x, unsigned short reg,
int bytes, void *src)
{
struct i2c_client *i2c = wm831x->control_data;
struct i2c_msg xfer[2];
int ret;
reg = cpu_to_be16(reg);
xfer[0].addr = i2c->addr;
xfer[0].flags = 0;
xfer[0].len = 2;
xfer[0].buf = (char *)®
xfer[1].addr = i2c->addr;
xfer[1].flags = I2C_M_NOSTART;
xfer[1].len = bytes;
xfer[1].buf = (char *)src;
ret = i2c_transfer(i2c->adapter, xfer, 2);
if (ret < 0)
return ret;
if (ret != 2)
return -EIO;
return 0;
}
static int wm831x_i2c_probe(struct i2c_client *i2c,
const struct i2c_device_id *id)
{
struct wm831x *wm831x;
wm831x = kzalloc(sizeof(struct wm831x), GFP_KERNEL);
if (wm831x == NULL)
return -ENOMEM;
i2c_set_clientdata(i2c, wm831x);
wm831x->dev = &i2c->dev;
wm831x->control_data = i2c;
wm831x->read_dev = wm831x_i2c_read_device;
wm831x->write_dev = wm831x_i2c_write_device;
return wm831x_device_init(wm831x, id->driver_data, i2c->irq);
}
static int wm831x_i2c_remove(struct i2c_client *i2c)
{
struct wm831x *wm831x = i2c_get_clientdata(i2c);
wm831x_device_exit(wm831x);
return 0;
}
static int wm831x_i2c_suspend(struct device *dev)
{
struct wm831x *wm831x = dev_get_drvdata(dev);
return wm831x_device_suspend(wm831x);
}
static const struct i2c_device_id wm831x_i2c_id[] = {
{ "wm8310", WM8310 },
{ "wm8311", WM8311 },
{ "wm8312", WM8312 },
{ "wm8320", WM8320 },
{ "wm8321", WM8321 },
{ "wm8325", WM8325 },
{ "wm8326", WM8326 },
{ }
};
MODULE_DEVICE_TABLE(i2c, wm831x_i2c_id);
static const struct dev_pm_ops wm831x_pm_ops = {
.suspend = wm831x_i2c_suspend,
};
static struct i2c_driver wm831x_i2c_driver = {
.driver = {
.name = "wm831x",
.owner = THIS_MODULE,
.pm = &wm831x_pm_ops,
},
.probe = wm831x_i2c_probe,
.remove = wm831x_i2c_remove,
.id_table = wm831x_i2c_id,
};
static int __init wm831x_i2c_init(void)
{
int ret;
ret = i2c_add_driver(&wm831x_i2c_driver);
if (ret != 0)
pr_err("Failed to register wm831x I2C driver: %d\n", ret);
return ret;
}
subsys_initcall(wm831x_i2c_init);
static void __exit wm831x_i2c_exit(void)
{
i2c_del_driver(&wm831x_i2c_driver);
}
module_exit(wm831x_i2c_exit);
