xref: /linux/drivers/input/misc/ad714x-i2c.c (revision 7a996d3ab150bb0e1b71fa182f70199a703efdd1)
1 /*
2  * AD714X CapTouch Programmable Controller driver (I2C bus)
3  *
4  * Copyright 2009 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 "ad714x.h"
14 
15 #ifdef CONFIG_PM
16 static int ad714x_i2c_suspend(struct i2c_client *client, pm_message_t message)
17 {
18 	return ad714x_disable(i2c_get_clientdata(client));
19 }
20 
21 static int ad714x_i2c_resume(struct i2c_client *client)
22 {
23 	return ad714x_enable(i2c_get_clientdata(client));
24 }
25 #else
26 # define ad714x_i2c_suspend NULL
27 # define ad714x_i2c_resume  NULL
28 #endif
29 
30 static int ad714x_i2c_write(struct device *dev, unsigned short reg,
31 				unsigned short data)
32 {
33 	struct i2c_client *client = to_i2c_client(dev);
34 	int ret = 0;
35 	u8 *_reg = (u8 *)&reg;
36 	u8 *_data = (u8 *)&data;
37 
38 	u8 tx[4] = {
39 		_reg[1],
40 		_reg[0],
41 		_data[1],
42 		_data[0]
43 	};
44 
45 	ret = i2c_master_send(client, tx, 4);
46 	if (ret < 0)
47 		dev_err(&client->dev, "I2C write error\n");
48 
49 	return ret;
50 }
51 
52 static int ad714x_i2c_read(struct device *dev, unsigned short reg,
53 				unsigned short *data)
54 {
55 	struct i2c_client *client = to_i2c_client(dev);
56 	int ret = 0;
57 	u8 *_reg = (u8 *)&reg;
58 	u8 *_data = (u8 *)data;
59 
60 	u8 tx[2] = {
61 		_reg[1],
62 		_reg[0]
63 	};
64 	u8 rx[2];
65 
66 	ret = i2c_master_send(client, tx, 2);
67 	if (ret >= 0)
68 		ret = i2c_master_recv(client, rx, 2);
69 
70 	if (unlikely(ret < 0)) {
71 		dev_err(&client->dev, "I2C read error\n");
72 	} else {
73 		_data[0] = rx[1];
74 		_data[1] = rx[0];
75 	}
76 
77 	return ret;
78 }
79 
80 static int __devinit ad714x_i2c_probe(struct i2c_client *client,
81 					const struct i2c_device_id *id)
82 {
83 	struct ad714x_chip *chip;
84 
85 	chip = ad714x_probe(&client->dev, BUS_I2C, client->irq,
86 			    ad714x_i2c_read, ad714x_i2c_write);
87 	if (IS_ERR(chip))
88 		return PTR_ERR(chip);
89 
90 	i2c_set_clientdata(client, chip);
91 
92 	return 0;
93 }
94 
95 static int __devexit ad714x_i2c_remove(struct i2c_client *client)
96 {
97 	struct ad714x_chip *chip = i2c_get_clientdata(client);
98 
99 	ad714x_remove(chip);
100 
101 	return 0;
102 }
103 
104 static const struct i2c_device_id ad714x_id[] = {
105 	{ "ad7142_captouch", 0 },
106 	{ "ad7143_captouch", 0 },
107 	{ "ad7147_captouch", 0 },
108 	{ "ad7147a_captouch", 0 },
109 	{ "ad7148_captouch", 0 },
110 	{ }
111 };
112 MODULE_DEVICE_TABLE(i2c, ad714x_id);
113 
114 static struct i2c_driver ad714x_i2c_driver = {
115 	.driver = {
116 		.name = "ad714x_captouch",
117 	},
118 	.probe    = ad714x_i2c_probe,
119 	.remove   = __devexit_p(ad714x_i2c_remove),
120 	.suspend  = ad714x_i2c_suspend,
121 	.resume	  = ad714x_i2c_resume,
122 	.id_table = ad714x_id,
123 };
124 
125 static __init int ad714x_i2c_init(void)
126 {
127 	return i2c_add_driver(&ad714x_i2c_driver);
128 }
129 module_init(ad714x_i2c_init);
130 
131 static __exit void ad714x_i2c_exit(void)
132 {
133 	i2c_del_driver(&ad714x_i2c_driver);
134 }
135 module_exit(ad714x_i2c_exit);
136 
137 MODULE_DESCRIPTION("Analog Devices AD714X Capacitance Touch Sensor I2C Bus Driver");
138 MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
139 MODULE_LICENSE("GPL");
140