mfd: Fix dangling pointers
[linux-2.6.git] / drivers / mfd / wm8350-i2c.c
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 #include <linux/slab.h>
23
24 static int wm8350_i2c_read_device(struct wm8350 *wm8350, char reg,
25                                   int bytes, void *dest)
26 {
27         int ret;
28
29         ret = i2c_master_send(wm8350->i2c_client, &reg, 1);
30         if (ret < 0)
31                 return ret;
32         ret = i2c_master_recv(wm8350->i2c_client, dest, bytes);
33         if (ret < 0)
34                 return ret;
35         if (ret != bytes)
36                 return -EIO;
37         return 0;
38 }
39
40 static int wm8350_i2c_write_device(struct wm8350 *wm8350, char reg,
41                                    int bytes, void *src)
42 {
43         /* we add 1 byte for device register */
44         u8 msg[(WM8350_MAX_REGISTER << 1) + 1];
45         int ret;
46
47         if (bytes > ((WM8350_MAX_REGISTER << 1) + 1))
48                 return -EINVAL;
49
50         msg[0] = reg;
51         memcpy(&msg[1], src, bytes);
52         ret = i2c_master_send(wm8350->i2c_client, msg, bytes + 1);
53         if (ret < 0)
54                 return ret;
55         if (ret != bytes + 1)
56                 return -EIO;
57         return 0;
58 }
59
60 static int wm8350_i2c_probe(struct i2c_client *i2c,
61                             const struct i2c_device_id *id)
62 {
63         struct wm8350 *wm8350;
64         int ret = 0;
65
66         wm8350 = kzalloc(sizeof(struct wm8350), GFP_KERNEL);
67         if (wm8350 == NULL) {
68                 kfree(i2c);
69                 return -ENOMEM;
70         }
71
72         i2c_set_clientdata(i2c, wm8350);
73         wm8350->dev = &i2c->dev;
74         wm8350->i2c_client = i2c;
75         wm8350->read_dev = wm8350_i2c_read_device;
76         wm8350->write_dev = wm8350_i2c_write_device;
77
78         ret = wm8350_device_init(wm8350, i2c->irq, i2c->dev.platform_data);
79         if (ret < 0)
80                 goto err;
81
82         return ret;
83
84 err:
85         i2c_set_clientdata(i2c, NULL);
86         kfree(wm8350);
87         return ret;
88 }
89
90 static int wm8350_i2c_remove(struct i2c_client *i2c)
91 {
92         struct wm8350 *wm8350 = i2c_get_clientdata(i2c);
93
94         wm8350_device_exit(wm8350);
95         i2c_set_clientdata(i2c, NULL);
96         kfree(wm8350);
97
98         return 0;
99 }
100
101 static const struct i2c_device_id wm8350_i2c_id[] = {
102        { "wm8350", 0 },
103        { "wm8351", 0 },
104        { "wm8352", 0 },
105        { }
106 };
107 MODULE_DEVICE_TABLE(i2c, wm8350_i2c_id);
108
109
110 static struct i2c_driver wm8350_i2c_driver = {
111         .driver = {
112                    .name = "wm8350",
113                    .owner = THIS_MODULE,
114         },
115         .probe = wm8350_i2c_probe,
116         .remove = wm8350_i2c_remove,
117         .id_table = wm8350_i2c_id,
118 };
119
120 static int __init wm8350_i2c_init(void)
121 {
122         return i2c_add_driver(&wm8350_i2c_driver);
123 }
124 /* init early so consumer devices can complete system boot */
125 subsys_initcall(wm8350_i2c_init);
126
127 static void __exit wm8350_i2c_exit(void)
128 {
129         i2c_del_driver(&wm8350_i2c_driver);
130 }
131 module_exit(wm8350_i2c_exit);
132
133 MODULE_DESCRIPTION("I2C support for the WM8350 AudioPlus PMIC");
134 MODULE_LICENSE("GPL");