xref: /openbmc/linux/drivers/input/misc/ad714x-i2c.c (revision 2cf1c348)
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");
111