xref: /openbmc/linux/drivers/mfd/wm8350-i2c.c (revision fd589a8f)
1 /*
2  * wm8350-i2c.c  --  Generic I2C driver for Wolfson WM8350 PMIC
3  *
4  * Copyright 2007, 2008 Wolfson Microelectronics PLC.
5  *
6  * Author: Liam Girdwood
7  *         linux@wolfsonmicro.com
8  *
9  *  This program is free software; you can redistribute  it and/or modify it
10  *  under  the terms of  the GNU General  Public License as published by the
11  *  Free Software Foundation;  either version 2 of the  License, or (at your
12  *  option) any later version.
13  *
14  */
15 
16 #include <linux/module.h>
17 #include <linux/moduleparam.h>
18 #include <linux/init.h>
19 #include <linux/i2c.h>
20 #include <linux/platform_device.h>
21 #include <linux/mfd/wm8350/core.h>
22 
23 static int wm8350_i2c_read_device(struct wm8350 *wm8350, char reg,
24 				  int bytes, void *dest)
25 {
26 	int ret;
27 
28 	ret = i2c_master_send(wm8350->i2c_client, &reg, 1);
29 	if (ret < 0)
30 		return ret;
31 	ret = i2c_master_recv(wm8350->i2c_client, dest, bytes);
32 	if (ret < 0)
33 		return ret;
34 	if (ret != bytes)
35 		return -EIO;
36 	return 0;
37 }
38 
39 static int wm8350_i2c_write_device(struct wm8350 *wm8350, char reg,
40 				   int bytes, void *src)
41 {
42 	/* we add 1 byte for device register */
43 	u8 msg[(WM8350_MAX_REGISTER << 1) + 1];
44 	int ret;
45 
46 	if (bytes > ((WM8350_MAX_REGISTER << 1) + 1))
47 		return -EINVAL;
48 
49 	msg[0] = reg;
50 	memcpy(&msg[1], src, bytes);
51 	ret = i2c_master_send(wm8350->i2c_client, msg, bytes + 1);
52 	if (ret < 0)
53 		return ret;
54 	if (ret != bytes + 1)
55 		return -EIO;
56 	return 0;
57 }
58 
59 static int wm8350_i2c_probe(struct i2c_client *i2c,
60 			    const struct i2c_device_id *id)
61 {
62 	struct wm8350 *wm8350;
63 	int ret = 0;
64 
65 	wm8350 = kzalloc(sizeof(struct wm8350), GFP_KERNEL);
66 	if (wm8350 == NULL) {
67 		kfree(i2c);
68 		return -ENOMEM;
69 	}
70 
71 	i2c_set_clientdata(i2c, wm8350);
72 	wm8350->dev = &i2c->dev;
73 	wm8350->i2c_client = i2c;
74 	wm8350->read_dev = wm8350_i2c_read_device;
75 	wm8350->write_dev = wm8350_i2c_write_device;
76 
77 	ret = wm8350_device_init(wm8350, i2c->irq, i2c->dev.platform_data);
78 	if (ret < 0)
79 		goto err;
80 
81 	return ret;
82 
83 err:
84 	kfree(wm8350);
85 	return ret;
86 }
87 
88 static int wm8350_i2c_remove(struct i2c_client *i2c)
89 {
90 	struct wm8350 *wm8350 = i2c_get_clientdata(i2c);
91 
92 	wm8350_device_exit(wm8350);
93 	kfree(wm8350);
94 
95 	return 0;
96 }
97 
98 static const struct i2c_device_id wm8350_i2c_id[] = {
99        { "wm8350", 0 },
100        { "wm8351", 0 },
101        { "wm8352", 0 },
102        { }
103 };
104 MODULE_DEVICE_TABLE(i2c, wm8350_i2c_id);
105 
106 
107 static struct i2c_driver wm8350_i2c_driver = {
108 	.driver = {
109 		   .name = "wm8350",
110 		   .owner = THIS_MODULE,
111 	},
112 	.probe = wm8350_i2c_probe,
113 	.remove = wm8350_i2c_remove,
114 	.id_table = wm8350_i2c_id,
115 };
116 
117 static int __init wm8350_i2c_init(void)
118 {
119 	return i2c_add_driver(&wm8350_i2c_driver);
120 }
121 /* init early so consumer devices can complete system boot */
122 subsys_initcall(wm8350_i2c_init);
123 
124 static void __exit wm8350_i2c_exit(void)
125 {
126 	i2c_del_driver(&wm8350_i2c_driver);
127 }
128 module_exit(wm8350_i2c_exit);
129 
130 MODULE_DESCRIPTION("I2C support for the WM8350 AudioPlus PMIC");
131 MODULE_LICENSE("GPL");
132