ad714x-i2c.c

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/*
 * AD714X CapTouch Programmable Controller driver (I2C bus)
 *
 * Copyright 2009-2011 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 "ad714x.h"

#ifdef CONFIG_PM
static int ad714x_i2c_suspend(struct device *dev)
{
    return ad714x_disable(i2c_get_clientdata(to_i2c_client(dev)));
}

static int ad714x_i2c_resume(struct device *dev)
{
    return ad714x_enable(i2c_get_clientdata(to_i2c_client(dev)));
}
#endif

static SIMPLE_DEV_PM_OPS(ad714x_i2c_pm, ad714x_i2c_suspend, ad714x_i2c_resume);

static int ad714x_i2c_write(struct ad714x_chip *chip,
                unsigned short reg, unsigned short data)
{
    struct i2c_client *client = to_i2c_client(chip->dev);
    int error;

    chip->xfer_buf[0] = cpu_to_be16(reg);
    chip->xfer_buf[1] = cpu_to_be16(data);

    error = i2c_master_send(client, (u8 *)chip->xfer_buf,
                2 * sizeof(*chip->xfer_buf));
    if (unlikely(error < 0)) {
        dev_err(&client->dev, "I2C write error: %d\n", error);
        return error;
    }

    return 0;
}

static int ad714x_i2c_read(struct ad714x_chip *chip,
               unsigned short reg, unsigned short *data, size_t len)
{
    struct i2c_client *client = to_i2c_client(chip->dev);
    int i;
    int error;

    chip->xfer_buf[0] = cpu_to_be16(reg);

    error = i2c_master_send(client, (u8 *)chip->xfer_buf,
                sizeof(*chip->xfer_buf));
    if (error >= 0)
        error = i2c_master_recv(client, (u8 *)chip->xfer_buf,
                    len * sizeof(*chip->xfer_buf));

    if (unlikely(error < 0)) {
        dev_err(&client->dev, "I2C read error: %d\n", error);
        return error;
    }

    for (i = 0; i < len; i++)
        data[i] = be16_to_cpu(chip->xfer_buf[i]);

    return 0;
}

static int __devinit ad714x_i2c_probe(struct i2c_client *client,
                    const struct i2c_device_id *id)
{
    struct ad714x_chip *chip;

    chip = ad714x_probe(&client->dev, BUS_I2C, client->irq,
                ad714x_i2c_read, ad714x_i2c_write);
    if (IS_ERR(chip))
        return PTR_ERR(chip);

    i2c_set_clientdata(client, chip);

    return 0;
}

static int __devexit ad714x_i2c_remove(struct i2c_client *client)
{
    struct ad714x_chip *chip = i2c_get_clientdata(client);

    ad714x_remove(chip);

    return 0;
}

static const struct i2c_device_id ad714x_id[] = {
    { "ad7142_captouch", 0 },
    { "ad7143_captouch", 0 },
    { "ad7147_captouch", 0 },
    { "ad7147a_captouch", 0 },
    { "ad7148_captouch", 0 },
    { }
};
MODULE_DEVICE_TABLE(i2c, ad714x_id);

static struct i2c_driver ad714x_i2c_driver = {
    .driver = {
        .name = "ad714x_captouch",
        .pm   = &ad714x_i2c_pm,
    },
    .probe    = ad714x_i2c_probe,
    .remove   = __devexit_p(ad714x_i2c_remove),
    .id_table = ad714x_id,
};

module_i2c_driver(ad714x_i2c_driver);

MODULE_DESCRIPTION("Analog Devices AD714X Capacitance Touch Sensor I2C Bus Driver");
MODULE_AUTHOR("Barry Song <[email protected]>");
MODULE_LICENSE("GPL");