drivers/input/misc/ad714x-i2c.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * AD714X CapTouch Programmable Controller driver (I2C bus)
   4  *
   5  * Copyright 2009-2011 Analog Devices Inc.
   6  */
   7
   8 #include <linux/input.h>        /* BUS_I2C */
   9 #include <linux/i2c.h>
  10 #include <linux/module.h>
  11 #include <linux/types.h>
  12 #include <linux/pm.h>
  13 #include "ad714x.h"
  14
  15 static int __maybe_unused ad714x_i2c_suspend(struct device *dev)
  16 {
  17         return ad714x_disable(i2c_get_clientdata(to_i2c_client(dev)));
  18 }
  19
  20 static int __maybe_unused ad714x_i2c_resume(struct device *dev)
  21 {
  22         return ad714x_enable(i2c_get_clientdata(to_i2c_client(dev)));
  23 }
  24
  25 static SIMPLE_DEV_PM_OPS(ad714x_i2c_pm, ad714x_i2c_suspend, ad714x_i2c_resume);
  26
  27 static int ad714x_i2c_write(struct ad714x_chip *chip,
  28                             unsigned short reg, unsigned short data)
  29 {
  30         struct i2c_client *client = to_i2c_client(chip->dev);
  31         int error;
  32
  33         chip->xfer_buf[0] = cpu_to_be16(reg);
  34         chip->xfer_buf[1] = cpu_to_be16(data);
  35
  36         error = i2c_master_send(client, (u8 *)chip->xfer_buf,
  37                                 2 * sizeof(*chip->xfer_buf));
  38         if (unlikely(error < 0)) {
  39                 dev_err(&client->dev, "I2C write error: %d\n", error);
  40                 return error;
  41         }
  42
  43         return 0;
  44 }
  45
  46 static int ad714x_i2c_read(struct ad714x_chip *chip,
  47                            unsigned short reg, unsigned short *data, size_t len)
  48 {
  49         struct i2c_client *client = to_i2c_client(chip->dev);
  50         int i;
  51         int error;
  52
  53         chip->xfer_buf[0] = cpu_to_be16(reg);
  54
  55         error = i2c_master_send(client, (u8 *)chip->xfer_buf,
  56                                 sizeof(*chip->xfer_buf));
  57         if (error >= 0)
  58                 error = i2c_master_recv(client, (u8 *)chip->xfer_buf,
  59                                         len * sizeof(*chip->xfer_buf));
  60
  61         if (unlikely(error < 0)) {
  62                 dev_err(&client->dev, "I2C read error: %d\n", error);
  63                 return error;
  64         }
  65
  66         for (i = 0; i < len; i++)
  67                 data[i] = be16_to_cpu(chip->xfer_buf[i]);
  68
  69         return 0;
  70 }
  71
  72 static int ad714x_i2c_probe(struct i2c_client *client,
  73                                         const struct i2c_device_id *id)
  74 {
  75         struct ad714x_chip *chip;
  76
  77         chip = ad714x_probe(&client->dev, BUS_I2C, client->irq,
  78                             ad714x_i2c_read, ad714x_i2c_write);
  79         if (IS_ERR(chip))
  80                 return PTR_ERR(chip);
  81
  82         i2c_set_clientdata(client, chip);
  83
  84         return 0;
  85 }
  86
  87 static const struct i2c_device_id ad714x_id[] = {
  88         { "ad7142_captouch", 0 },
  89         { "ad7143_captouch", 0 },
  90         { "ad7147_captouch", 0 },
  91         { "ad7147a_captouch", 0 },
  92         { "ad7148_captouch", 0 },
  93         { }
  94 };
  95 MODULE_DEVICE_TABLE(i2c, ad714x_id);
  96
  97 static struct i2c_driver ad714x_i2c_driver = {
  98         .driver = {
  99                 .name = "ad714x_captouch",
 100                 .pm   = &ad714x_i2c_pm,
 101         },
 102         .probe    = ad714x_i2c_probe,
 103         .id_table = ad714x_id,
 104 };
 105
 106 module_i2c_driver(ad714x_i2c_driver);
 107
 108 MODULE_DESCRIPTION("Analog Devices AD714X Capacitance Touch Sensor I2C Bus Driver");
 109 MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
 110 MODULE_LICENSE("GPL");