xref: /openbmc/linux/drivers/input/misc/ad714x-i2c.c (revision 05bcf503)
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 
16 #ifdef CONFIG_PM
17 static int ad714x_i2c_suspend(struct device *dev)
18 {
19 	return ad714x_disable(i2c_get_clientdata(to_i2c_client(dev)));
20 }
21 
22 static int ad714x_i2c_resume(struct device *dev)
23 {
24 	return ad714x_enable(i2c_get_clientdata(to_i2c_client(dev)));
25 }
26 #endif
27 
28 static SIMPLE_DEV_PM_OPS(ad714x_i2c_pm, ad714x_i2c_suspend, ad714x_i2c_resume);
29 
30 static int ad714x_i2c_write(struct ad714x_chip *chip,
31 			    unsigned short reg, unsigned short data)
32 {
33 	struct i2c_client *client = to_i2c_client(chip->dev);
34 	int error;
35 
36 	chip->xfer_buf[0] = cpu_to_be16(reg);
37 	chip->xfer_buf[1] = cpu_to_be16(data);
38 
39 	error = i2c_master_send(client, (u8 *)chip->xfer_buf,
40 				2 * sizeof(*chip->xfer_buf));
41 	if (unlikely(error < 0)) {
42 		dev_err(&client->dev, "I2C write error: %d\n", error);
43 		return error;
44 	}
45 
46 	return 0;
47 }
48 
49 static int ad714x_i2c_read(struct ad714x_chip *chip,
50 			   unsigned short reg, unsigned short *data, size_t len)
51 {
52 	struct i2c_client *client = to_i2c_client(chip->dev);
53 	int i;
54 	int error;
55 
56 	chip->xfer_buf[0] = cpu_to_be16(reg);
57 
58 	error = i2c_master_send(client, (u8 *)chip->xfer_buf,
59 				sizeof(*chip->xfer_buf));
60 	if (error >= 0)
61 		error = i2c_master_recv(client, (u8 *)chip->xfer_buf,
62 					len * sizeof(*chip->xfer_buf));
63 
64 	if (unlikely(error < 0)) {
65 		dev_err(&client->dev, "I2C read error: %d\n", error);
66 		return error;
67 	}
68 
69 	for (i = 0; i < len; i++)
70 		data[i] = be16_to_cpu(chip->xfer_buf[i]);
71 
72 	return 0;
73 }
74 
75 static int __devinit ad714x_i2c_probe(struct i2c_client *client,
76 					const struct i2c_device_id *id)
77 {
78 	struct ad714x_chip *chip;
79 
80 	chip = ad714x_probe(&client->dev, BUS_I2C, client->irq,
81 			    ad714x_i2c_read, ad714x_i2c_write);
82 	if (IS_ERR(chip))
83 		return PTR_ERR(chip);
84 
85 	i2c_set_clientdata(client, chip);
86 
87 	return 0;
88 }
89 
90 static int __devexit ad714x_i2c_remove(struct i2c_client *client)
91 {
92 	struct ad714x_chip *chip = i2c_get_clientdata(client);
93 
94 	ad714x_remove(chip);
95 
96 	return 0;
97 }
98 
99 static const struct i2c_device_id ad714x_id[] = {
100 	{ "ad7142_captouch", 0 },
101 	{ "ad7143_captouch", 0 },
102 	{ "ad7147_captouch", 0 },
103 	{ "ad7147a_captouch", 0 },
104 	{ "ad7148_captouch", 0 },
105 	{ }
106 };
107 MODULE_DEVICE_TABLE(i2c, ad714x_id);
108 
109 static struct i2c_driver ad714x_i2c_driver = {
110 	.driver = {
111 		.name = "ad714x_captouch",
112 		.pm   = &ad714x_i2c_pm,
113 	},
114 	.probe    = ad714x_i2c_probe,
115 	.remove   = __devexit_p(ad714x_i2c_remove),
116 	.id_table = ad714x_id,
117 };
118 
119 module_i2c_driver(ad714x_i2c_driver);
120 
121 MODULE_DESCRIPTION("Analog Devices AD714X Capacitance Touch Sensor I2C Bus Driver");
122 MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
123 MODULE_LICENSE("GPL");
124