LXR linux/drivers/input/misc/ad714x-i2c.c

   1/*
   2 * AD714X CapTouch Programmable Controller driver (I2C bus)
   3 *
   4 * Copyright 2009-2011 Analog Devices Inc.
   5 *
   6 * Licensed under the GPL-2 or later.
   7 */
   8
   9#include <linux/input.h>        /* BUS_I2C */
  10#include <linux/i2c.h>
  11#include <linux/module.h>
  12#include <linux/types.h>
  13#include <linux/pm.h>
  14#include "ad714x.h"
  15
  16static int __maybe_unused ad714x_i2c_suspend(struct device *dev)
  17{
  18        return ad714x_disable(i2c_get_clientdata(to_i2c_client(dev)));
  19}
  20
  21static int __maybe_unused ad714x_i2c_resume(struct device *dev)
  22{
  23        return ad714x_enable(i2c_get_clientdata(to_i2c_client(dev)));
  24}
  25
  26static SIMPLE_DEV_PM_OPS(ad714x_i2c_pm, ad714x_i2c_suspend, ad714x_i2c_resume);
  27
  28static int ad714x_i2c_write(struct ad714x_chip *chip,
  29                            unsigned short reg, unsigned short data)
  30{
  31        struct i2c_client *client = to_i2c_client(chip->dev);
  32        int error;
  33
  34        chip->xfer_buf[0] = cpu_to_be16(reg);
  35        chip->xfer_buf[1] = cpu_to_be16(data);
  36
  37        error = i2c_master_send(client, (u8 *)chip->xfer_buf,
  38                                2 * sizeof(*chip->xfer_buf));
  39        if (unlikely(error < 0)) {
  40                dev_err(&client->dev, "I2C write error: %d\n", error);
  41                return error;
  42        }
  43
  44        return 0;
  45}
  46
  47static int ad714x_i2c_read(struct ad714x_chip *chip,
  48                           unsigned short reg, unsigned short *data, size_t len)
  49{
  50        struct i2c_client *client = to_i2c_client(chip->dev);
  51        int i;
  52        int error;
  53
  54        chip->xfer_buf[0] = cpu_to_be16(reg);
  55
  56        error = i2c_master_send(client, (u8 *)chip->xfer_buf,
  57                                sizeof(*chip->xfer_buf));
  58        if (error >= 0)
  59                error = i2c_master_recv(client, (u8 *)chip->xfer_buf,
  60                                        len * sizeof(*chip->xfer_buf));
  61
  62        if (unlikely(error < 0)) {
  63                dev_err(&client->dev, "I2C read error: %d\n", error);
  64                return error;
  65        }
  66
  67        for (i = 0; i < len; i++)
  68                data[i] = be16_to_cpu(chip->xfer_buf[i]);
  69
  70        return 0;
  71}
  72
  73static int ad714x_i2c_probe(struct i2c_client *client,
  74                                        const struct i2c_device_id *id)
  75{
  76        struct ad714x_chip *chip;
  77
  78        chip = ad714x_probe(&client->dev, BUS_I2C, client->irq,
  79                            ad714x_i2c_read, ad714x_i2c_write);
  80        if (IS_ERR(chip))
  81                return PTR_ERR(chip);
  82
  83        i2c_set_clientdata(client, chip);
  84
  85        return 0;
  86}
  87
  88static const struct i2c_device_id ad714x_id[] = {
  89        { "ad7142_captouch", 0 },
  90        { "ad7143_captouch", 0 },
  91        { "ad7147_captouch", 0 },
  92        { "ad7147a_captouch", 0 },
  93        { "ad7148_captouch", 0 },
  94        { }
  95};
  96MODULE_DEVICE_TABLE(i2c, ad714x_id);
  97
  98static struct i2c_driver ad714x_i2c_driver = {
  99        .driver = {
 100                .name = "ad714x_captouch",
 101                .pm   = &ad714x_i2c_pm,
 102        },
 103        .probe    = ad714x_i2c_probe,
 104        .id_table = ad714x_id,
 105};
 106
 107module_i2c_driver(ad714x_i2c_driver);
 108
 109MODULE_DESCRIPTION("Analog Devices AD714X Capacitance Touch Sensor I2C Bus Driver");
 110MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
 111MODULE_LICENSE("GPL");
 112