linux/drivers/input/touchscreen/ad7879-i2c.c
Jonathan Cameron 75255b29d4 Input: ad7879-i2c - use swapped variant of i2c_smbus_read_word_data
This variant was introduced in

i2c: boilerplate function for byte swapped smbus_write/read_word_data

This also has the side effect of ensuring any errors from the i2c
read and no longer mangled.

Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2011-11-30 23:41:44 -08:00

120 lines
2.6 KiB
C

/*
* AD7879-1/AD7889-1 touchscreen (I2C bus)
*
* Copyright (C) 2008-2010 Michael Hennerich, Analog Devices Inc.
*
* Licensed under the GPL-2 or later.
*/
#include <linux/input.h> /* BUS_I2C */
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/pm.h>
#include "ad7879.h"
#define AD7879_DEVID 0x79 /* AD7879-1/AD7889-1 */
/* All registers are word-sized.
* AD7879 uses a high-byte first convention.
*/
static int ad7879_i2c_read(struct device *dev, u8 reg)
{
struct i2c_client *client = to_i2c_client(dev);
return i2c_smbus_read_word_swapped(client, reg);
}
static int ad7879_i2c_multi_read(struct device *dev,
u8 first_reg, u8 count, u16 *buf)
{
struct i2c_client *client = to_i2c_client(dev);
u8 idx;
i2c_smbus_read_i2c_block_data(client, first_reg, count * 2, (u8 *)buf);
for (idx = 0; idx < count; ++idx)
buf[idx] = swab16(buf[idx]);
return 0;
}
static int ad7879_i2c_write(struct device *dev, u8 reg, u16 val)
{
struct i2c_client *client = to_i2c_client(dev);
return i2c_smbus_write_word_swapped(client, reg, val);
}
static const struct ad7879_bus_ops ad7879_i2c_bus_ops = {
.bustype = BUS_I2C,
.read = ad7879_i2c_read,
.multi_read = ad7879_i2c_multi_read,
.write = ad7879_i2c_write,
};
static int __devinit ad7879_i2c_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct ad7879 *ts;
if (!i2c_check_functionality(client->adapter,
I2C_FUNC_SMBUS_WORD_DATA)) {
dev_err(&client->dev, "SMBUS Word Data not Supported\n");
return -EIO;
}
ts = ad7879_probe(&client->dev, AD7879_DEVID, client->irq,
&ad7879_i2c_bus_ops);
if (IS_ERR(ts))
return PTR_ERR(ts);
i2c_set_clientdata(client, ts);
return 0;
}
static int __devexit ad7879_i2c_remove(struct i2c_client *client)
{
struct ad7879 *ts = i2c_get_clientdata(client);
ad7879_remove(ts);
return 0;
}
static const struct i2c_device_id ad7879_id[] = {
{ "ad7879", 0 },
{ "ad7889", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, ad7879_id);
static struct i2c_driver ad7879_i2c_driver = {
.driver = {
.name = "ad7879",
.owner = THIS_MODULE,
.pm = &ad7879_pm_ops,
},
.probe = ad7879_i2c_probe,
.remove = __devexit_p(ad7879_i2c_remove),
.id_table = ad7879_id,
};
static int __init ad7879_i2c_init(void)
{
return i2c_add_driver(&ad7879_i2c_driver);
}
module_init(ad7879_i2c_init);
static void __exit ad7879_i2c_exit(void)
{
i2c_del_driver(&ad7879_i2c_driver);
}
module_exit(ad7879_i2c_exit);
MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
MODULE_DESCRIPTION("AD7879(-1) touchscreen I2C bus driver");
MODULE_LICENSE("GPL");