xref: /openbmc/linux/drivers/gpio/gpio-max7300.c (revision 461ba3e7)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2009 Wolfram Sang, Pengutronix
4  *
5  * Check max730x.c for further details.
6  */
7 
8 #include <linux/module.h>
9 #include <linux/init.h>
10 #include <linux/platform_device.h>
11 #include <linux/mutex.h>
12 #include <linux/i2c.h>
13 #include <linux/spi/max7301.h>
14 #include <linux/slab.h>
15 
16 static int max7300_i2c_write(struct device *dev, unsigned int reg,
17 				unsigned int val)
18 {
19 	struct i2c_client *client = to_i2c_client(dev);
20 
21 	return i2c_smbus_write_byte_data(client, reg, val);
22 }
23 
24 static int max7300_i2c_read(struct device *dev, unsigned int reg)
25 {
26 	struct i2c_client *client = to_i2c_client(dev);
27 
28 	return i2c_smbus_read_byte_data(client, reg);
29 }
30 
31 static int max7300_probe(struct i2c_client *client)
32 {
33 	struct max7301 *ts;
34 
35 	if (!i2c_check_functionality(client->adapter,
36 			I2C_FUNC_SMBUS_BYTE_DATA))
37 		return -EIO;
38 
39 	ts = devm_kzalloc(&client->dev, sizeof(struct max7301), GFP_KERNEL);
40 	if (!ts)
41 		return -ENOMEM;
42 
43 	ts->read = max7300_i2c_read;
44 	ts->write = max7300_i2c_write;
45 	ts->dev = &client->dev;
46 
47 	return __max730x_probe(ts);
48 }
49 
50 static void max7300_remove(struct i2c_client *client)
51 {
52 	__max730x_remove(&client->dev);
53 }
54 
55 static const struct i2c_device_id max7300_id[] = {
56 	{ "max7300", 0 },
57 	{ }
58 };
59 MODULE_DEVICE_TABLE(i2c, max7300_id);
60 
61 static struct i2c_driver max7300_driver = {
62 	.driver = {
63 		.name = "max7300",
64 	},
65 	.probe_new = max7300_probe,
66 	.remove = max7300_remove,
67 	.id_table = max7300_id,
68 };
69 
70 static int __init max7300_init(void)
71 {
72 	return i2c_add_driver(&max7300_driver);
73 }
74 subsys_initcall(max7300_init);
75 
76 static void __exit max7300_exit(void)
77 {
78 	i2c_del_driver(&max7300_driver);
79 }
80 module_exit(max7300_exit);
81 
82 MODULE_AUTHOR("Wolfram Sang");
83 MODULE_LICENSE("GPL v2");
84 MODULE_DESCRIPTION("MAX7300 GPIO-Expander");
85