xref: /openbmc/linux/drivers/gpio/gpio-max7300.c (revision 8fdff1dc)
1 /*
2  * Copyright (C) 2009 Wolfram Sang, Pengutronix
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  *
8  * Check max730x.c for further details.
9  */
10 
11 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/platform_device.h>
14 #include <linux/mutex.h>
15 #include <linux/i2c.h>
16 #include <linux/spi/max7301.h>
17 #include <linux/slab.h>
18 
19 static int max7300_i2c_write(struct device *dev, unsigned int reg,
20 				unsigned int val)
21 {
22 	struct i2c_client *client = to_i2c_client(dev);
23 
24 	return i2c_smbus_write_byte_data(client, reg, val);
25 }
26 
27 static int max7300_i2c_read(struct device *dev, unsigned int reg)
28 {
29 	struct i2c_client *client = to_i2c_client(dev);
30 
31 	return i2c_smbus_read_byte_data(client, reg);
32 }
33 
34 static int max7300_probe(struct i2c_client *client,
35 			 const struct i2c_device_id *id)
36 {
37 	struct max7301 *ts;
38 	int ret;
39 
40 	if (!i2c_check_functionality(client->adapter,
41 			I2C_FUNC_SMBUS_BYTE_DATA))
42 		return -EIO;
43 
44 	ts = kzalloc(sizeof(struct max7301), GFP_KERNEL);
45 	if (!ts)
46 		return -ENOMEM;
47 
48 	ts->read = max7300_i2c_read;
49 	ts->write = max7300_i2c_write;
50 	ts->dev = &client->dev;
51 
52 	ret = __max730x_probe(ts);
53 	if (ret)
54 		kfree(ts);
55 	return ret;
56 }
57 
58 static int max7300_remove(struct i2c_client *client)
59 {
60 	return __max730x_remove(&client->dev);
61 }
62 
63 static const struct i2c_device_id max7300_id[] = {
64 	{ "max7300", 0 },
65 	{ }
66 };
67 MODULE_DEVICE_TABLE(i2c, max7300_id);
68 
69 static struct i2c_driver max7300_driver = {
70 	.driver = {
71 		.name = "max7300",
72 		.owner = THIS_MODULE,
73 	},
74 	.probe = max7300_probe,
75 	.remove = max7300_remove,
76 	.id_table = max7300_id,
77 };
78 
79 static int __init max7300_init(void)
80 {
81 	return i2c_add_driver(&max7300_driver);
82 }
83 subsys_initcall(max7300_init);
84 
85 static void __exit max7300_exit(void)
86 {
87 	i2c_del_driver(&max7300_driver);
88 }
89 module_exit(max7300_exit);
90 
91 MODULE_AUTHOR("Wolfram Sang");
92 MODULE_LICENSE("GPL v2");
93 MODULE_DESCRIPTION("MAX7300 GPIO-Expander");
94