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
15static int ad714x_i2c_write(struct ad714x_chip *chip,
16 unsigned short reg, unsigned short data)
17{
18 struct i2c_client *client = to_i2c_client(chip->dev);
19 int error;
20
21 chip->xfer_buf[0] = cpu_to_be16(reg);
22 chip->xfer_buf[1] = cpu_to_be16(data);
23
24 error = i2c_master_send(client, buf: (u8 *)chip->xfer_buf,
25 count: 2 * sizeof(*chip->xfer_buf));
26 if (unlikely(error < 0)) {
27 dev_err(&client->dev, "I2C write error: %d\n", error);
28 return error;
29 }
30
31 return 0;
32}
33
34static int ad714x_i2c_read(struct ad714x_chip *chip,
35 unsigned short reg, unsigned short *data, size_t len)
36{
37 struct i2c_client *client = to_i2c_client(chip->dev);
38 int i;
39 int error;
40
41 chip->xfer_buf[0] = cpu_to_be16(reg);
42
43 error = i2c_master_send(client, buf: (u8 *)chip->xfer_buf,
44 count: sizeof(*chip->xfer_buf));
45 if (error >= 0)
46 error = i2c_master_recv(client, buf: (u8 *)chip->xfer_buf,
47 count: len * sizeof(*chip->xfer_buf));
48
49 if (unlikely(error < 0)) {
50 dev_err(&client->dev, "I2C read error: %d\n", error);
51 return error;
52 }
53
54 for (i = 0; i < len; i++)
55 data[i] = be16_to_cpu(chip->xfer_buf[i]);
56
57 return 0;
58}
59
60static int ad714x_i2c_probe(struct i2c_client *client)
61{
62 struct ad714x_chip *chip;
63
64 chip = ad714x_probe(dev: &client->dev, BUS_I2C, irq: client->irq,
65 read: ad714x_i2c_read, write: ad714x_i2c_write);
66 if (IS_ERR(ptr: chip))
67 return PTR_ERR(ptr: chip);
68
69 i2c_set_clientdata(client, data: chip);
70
71 return 0;
72}
73
74static const struct i2c_device_id ad714x_id[] = {
75 { "ad7142_captouch" },
76 { "ad7143_captouch" },
77 { "ad7147_captouch" },
78 { "ad7147a_captouch" },
79 { "ad7148_captouch" },
80 { }
81};
82MODULE_DEVICE_TABLE(i2c, ad714x_id);
83
84static struct i2c_driver ad714x_i2c_driver = {
85 .driver = {
86 .name = "ad714x_captouch",
87 .pm = pm_sleep_ptr(&ad714x_pm),
88 },
89 .probe = ad714x_i2c_probe,
90 .id_table = ad714x_id,
91};
92
93module_i2c_driver(ad714x_i2c_driver);
94
95MODULE_DESCRIPTION("Analog Devices AD714X Capacitance Touch Sensor I2C Bus Driver");
96MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
97MODULE_LICENSE("GPL");
98

source code of linux/drivers/input/misc/ad714x-i2c.c