Commit | Line | Data |
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0062f6e5 SAS |
1 | #include <linux/kernel.h> |
2 | #include <linux/slab.h> | |
3 | #include <linux/module.h> | |
4 | #include <linux/err.h> | |
5 | ||
6 | #include <linux/usb/composite.h> | |
7 | ||
8 | static LIST_HEAD(func_list); | |
9 | static DEFINE_MUTEX(func_lock); | |
10 | ||
11 | static struct usb_function_instance *try_get_usb_function_instance(const char *name) | |
12 | { | |
13 | struct usb_function_driver *fd; | |
14 | struct usb_function_instance *fi; | |
15 | ||
16 | fi = ERR_PTR(-ENOENT); | |
17 | mutex_lock(&func_lock); | |
18 | list_for_each_entry(fd, &func_list, list) { | |
19 | ||
20 | if (strcmp(name, fd->name)) | |
21 | continue; | |
22 | ||
23 | if (!try_module_get(fd->mod)) { | |
24 | fi = ERR_PTR(-EBUSY); | |
25 | break; | |
26 | } | |
27 | fi = fd->alloc_inst(); | |
28 | if (IS_ERR(fi)) | |
29 | module_put(fd->mod); | |
30 | else | |
31 | fi->fd = fd; | |
32 | break; | |
33 | } | |
34 | mutex_unlock(&func_lock); | |
35 | return fi; | |
36 | } | |
37 | ||
38 | struct usb_function_instance *usb_get_function_instance(const char *name) | |
39 | { | |
40 | struct usb_function_instance *fi; | |
41 | int ret; | |
42 | ||
43 | fi = try_get_usb_function_instance(name); | |
44 | if (!IS_ERR(fi)) | |
45 | return fi; | |
46 | ret = PTR_ERR(fi); | |
47 | if (ret != -ENOENT) | |
48 | return fi; | |
49 | ret = request_module("usbfunc:%s", name); | |
50 | if (ret < 0) | |
51 | return ERR_PTR(ret); | |
52 | return try_get_usb_function_instance(name); | |
53 | } | |
54 | EXPORT_SYMBOL_GPL(usb_get_function_instance); | |
55 | ||
56 | struct usb_function *usb_get_function(struct usb_function_instance *fi) | |
57 | { | |
58 | struct usb_function *f; | |
59 | ||
60 | f = fi->fd->alloc_func(fi); | |
61 | if (IS_ERR(f)) | |
62 | return f; | |
63 | f->fi = fi; | |
64 | return f; | |
65 | } | |
66 | EXPORT_SYMBOL_GPL(usb_get_function); | |
67 | ||
68 | void usb_put_function_instance(struct usb_function_instance *fi) | |
69 | { | |
70 | struct module *mod; | |
71 | ||
72 | if (!fi) | |
73 | return; | |
74 | ||
75 | mod = fi->fd->mod; | |
76 | fi->free_func_inst(fi); | |
77 | module_put(mod); | |
78 | } | |
79 | EXPORT_SYMBOL_GPL(usb_put_function_instance); | |
80 | ||
81 | void usb_put_function(struct usb_function *f) | |
82 | { | |
83 | if (!f) | |
84 | return; | |
85 | ||
86 | f->free_func(f); | |
87 | } | |
88 | EXPORT_SYMBOL_GPL(usb_put_function); | |
89 | ||
90 | int usb_function_register(struct usb_function_driver *newf) | |
91 | { | |
92 | struct usb_function_driver *fd; | |
93 | int ret; | |
94 | ||
95 | ret = -EEXIST; | |
96 | ||
97 | mutex_lock(&func_lock); | |
98 | list_for_each_entry(fd, &func_list, list) { | |
99 | if (!strcmp(fd->name, newf->name)) | |
100 | goto out; | |
101 | } | |
102 | ret = 0; | |
103 | list_add_tail(&newf->list, &func_list); | |
104 | out: | |
105 | mutex_unlock(&func_lock); | |
106 | return ret; | |
107 | } | |
108 | EXPORT_SYMBOL_GPL(usb_function_register); | |
109 | ||
110 | void usb_function_unregister(struct usb_function_driver *fd) | |
111 | { | |
112 | mutex_lock(&func_lock); | |
113 | list_del(&fd->list); | |
114 | mutex_unlock(&func_lock); | |
115 | } | |
116 | EXPORT_SYMBOL_GPL(usb_function_unregister); |