xref: /openbmc/linux/drivers/input/misc/ad714x-i2c.c (revision 5da094ac)
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 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, (u8 *)chip->xfer_buf,
25 				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 
34 static 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, (u8 *)chip->xfer_buf,
44 				sizeof(*chip->xfer_buf));
45 	if (error >= 0)
46 		error = i2c_master_recv(client, (u8 *)chip->xfer_buf,
47 					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 
60 static int ad714x_i2c_probe(struct i2c_client *client)
61 {
62 	struct ad714x_chip *chip;
63 
64 	chip = ad714x_probe(&client->dev, BUS_I2C, client->irq,
65 			    ad714x_i2c_read, ad714x_i2c_write);
66 	if (IS_ERR(chip))
67 		return PTR_ERR(chip);
68 
69 	i2c_set_clientdata(client, chip);
70 
71 	return 0;
72 }
73 
74 static const struct i2c_device_id ad714x_id[] = {
75 	{ "ad7142_captouch", 0 },
76 	{ "ad7143_captouch", 0 },
77 	{ "ad7147_captouch", 0 },
78 	{ "ad7147a_captouch", 0 },
79 	{ "ad7148_captouch", 0 },
80 	{ }
81 };
82 MODULE_DEVICE_TABLE(i2c, ad714x_id);
83 
84 static struct i2c_driver ad714x_i2c_driver = {
85 	.driver = {
86 		.name = "ad714x_captouch",
87 		.pm   = pm_sleep_ptr(&ad714x_pm),
88 	},
89 	.probe_new = ad714x_i2c_probe,
90 	.id_table = ad714x_id,
91 };
92 
93 module_i2c_driver(ad714x_i2c_driver);
94 
95 MODULE_DESCRIPTION("Analog Devices AD714X Capacitance Touch Sensor I2C Bus Driver");
96 MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
97 MODULE_LICENSE("GPL");
98