1 /*
2  * AD7879-1/AD7889-1 touchscreen (I2C bus)
3  *
4  * Copyright (C) 2008-2010 Michael Hennerich, 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 
15 #include "ad7879.h"
16 
17 #define AD7879_DEVID		0x79	/* AD7879-1/AD7889-1 */
18 
19 #ifdef CONFIG_PM
20 static int ad7879_i2c_suspend(struct device *dev)
21 {
22 	struct i2c_client *client = to_i2c_client(dev);
23 	struct ad7879 *ts = i2c_get_clientdata(client);
24 
25 	ad7879_suspend(ts);
26 
27 	return 0;
28 }
29 
30 static int ad7879_i2c_resume(struct device *dev)
31 {
32 	struct i2c_client *client = to_i2c_client(dev);
33 	struct ad7879 *ts = i2c_get_clientdata(client);
34 
35 	ad7879_resume(ts);
36 
37 	return 0;
38 }
39 
40 static SIMPLE_DEV_PM_OPS(ad7879_i2c_pm, ad7879_i2c_suspend, ad7879_i2c_resume);
41 #endif
42 
43 /* All registers are word-sized.
44  * AD7879 uses a high-byte first convention.
45  */
46 static int ad7879_i2c_read(struct device *dev, u8 reg)
47 {
48 	struct i2c_client *client = to_i2c_client(dev);
49 
50 	return swab16(i2c_smbus_read_word_data(client, reg));
51 }
52 
53 static int ad7879_i2c_multi_read(struct device *dev,
54 				 u8 first_reg, u8 count, u16 *buf)
55 {
56 	struct i2c_client *client = to_i2c_client(dev);
57 	u8 idx;
58 
59 	i2c_smbus_read_i2c_block_data(client, first_reg, count * 2, (u8 *)buf);
60 
61 	for (idx = 0; idx < count; ++idx)
62 		buf[idx] = swab16(buf[idx]);
63 
64 	return 0;
65 }
66 
67 static int ad7879_i2c_write(struct device *dev, u8 reg, u16 val)
68 {
69 	struct i2c_client *client = to_i2c_client(dev);
70 
71 	return i2c_smbus_write_word_data(client, reg, swab16(val));
72 }
73 
74 static const struct ad7879_bus_ops ad7879_i2c_bus_ops = {
75 	.bustype	= BUS_I2C,
76 	.read		= ad7879_i2c_read,
77 	.multi_read	= ad7879_i2c_multi_read,
78 	.write		= ad7879_i2c_write,
79 };
80 
81 static int __devinit ad7879_i2c_probe(struct i2c_client *client,
82 				      const struct i2c_device_id *id)
83 {
84 	struct ad7879 *ts;
85 
86 	if (!i2c_check_functionality(client->adapter,
87 				     I2C_FUNC_SMBUS_WORD_DATA)) {
88 		dev_err(&client->dev, "SMBUS Word Data not Supported\n");
89 		return -EIO;
90 	}
91 
92 	ts = ad7879_probe(&client->dev, AD7879_DEVID, client->irq,
93 			  &ad7879_i2c_bus_ops);
94 	if (IS_ERR(ts))
95 		return PTR_ERR(ts);
96 
97 	i2c_set_clientdata(client, ts);
98 
99 	return 0;
100 }
101 
102 static int __devexit ad7879_i2c_remove(struct i2c_client *client)
103 {
104 	struct ad7879 *ts = i2c_get_clientdata(client);
105 
106 	ad7879_remove(ts);
107 
108 	return 0;
109 }
110 
111 static const struct i2c_device_id ad7879_id[] = {
112 	{ "ad7879", 0 },
113 	{ "ad7889", 0 },
114 	{ }
115 };
116 MODULE_DEVICE_TABLE(i2c, ad7879_id);
117 
118 static struct i2c_driver ad7879_i2c_driver = {
119 	.driver = {
120 		.name	= "ad7879",
121 		.owner	= THIS_MODULE,
122 #ifdef CONFIG_PM
123 		.pm	= &ad7879_i2c_pm,
124 #endif
125 	},
126 	.probe		= ad7879_i2c_probe,
127 	.remove		= __devexit_p(ad7879_i2c_remove),
128 	.id_table	= ad7879_id,
129 };
130 
131 static int __init ad7879_i2c_init(void)
132 {
133 	return i2c_add_driver(&ad7879_i2c_driver);
134 }
135 module_init(ad7879_i2c_init);
136 
137 static void __exit ad7879_i2c_exit(void)
138 {
139 	i2c_del_driver(&ad7879_i2c_driver);
140 }
141 module_exit(ad7879_i2c_exit);
142 
143 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
144 MODULE_DESCRIPTION("AD7879(-1) touchscreen I2C bus driver");
145 MODULE_LICENSE("GPL");
146 MODULE_ALIAS("i2c:ad7879");
147