1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * u_f.h |
4 | * |
5 | * Utility definitions for USB functions |
6 | * |
7 | * Copyright (c) 2013 Samsung Electronics Co., Ltd. |
8 | * http://www.samsung.com |
9 | * |
10 | * Author: Andrzej Pietrasiewicz <andrzejtp2010@gmail.com> |
11 | */ |
12 | |
13 | #ifndef __U_F_H__ |
14 | #define __U_F_H__ |
15 | |
16 | #include <linux/usb/gadget.h> |
17 | #include <linux/overflow.h> |
18 | |
19 | /* Variable Length Array Macros **********************************************/ |
20 | #define vla_group(groupname) size_t groupname##__next = 0 |
21 | #define vla_group_size(groupname) groupname##__next |
22 | |
23 | #define vla_item(groupname, type, name, n) \ |
24 | size_t groupname##_##name##__offset = ({ \ |
25 | size_t offset = 0; \ |
26 | if (groupname##__next != SIZE_MAX) { \ |
27 | size_t align_mask = __alignof__(type) - 1; \ |
28 | size_t size = array_size(n, sizeof(type)); \ |
29 | offset = (groupname##__next + align_mask) & \ |
30 | ~align_mask; \ |
31 | if (check_add_overflow(offset, size, \ |
32 | &groupname##__next)) { \ |
33 | groupname##__next = SIZE_MAX; \ |
34 | offset = 0; \ |
35 | } \ |
36 | } \ |
37 | offset; \ |
38 | }) |
39 | |
40 | #define vla_item_with_sz(groupname, type, name, n) \ |
41 | size_t groupname##_##name##__sz = array_size(n, sizeof(type)); \ |
42 | size_t groupname##_##name##__offset = ({ \ |
43 | size_t offset = 0; \ |
44 | if (groupname##__next != SIZE_MAX) { \ |
45 | size_t align_mask = __alignof__(type) - 1; \ |
46 | offset = (groupname##__next + align_mask) & \ |
47 | ~align_mask; \ |
48 | if (check_add_overflow(offset, groupname##_##name##__sz,\ |
49 | &groupname##__next)) { \ |
50 | groupname##__next = SIZE_MAX; \ |
51 | offset = 0; \ |
52 | } \ |
53 | } \ |
54 | offset; \ |
55 | }) |
56 | |
57 | #define vla_ptr(ptr, groupname, name) \ |
58 | ((void *) ((char *)ptr + groupname##_##name##__offset)) |
59 | |
60 | struct usb_ep; |
61 | struct usb_request; |
62 | |
63 | /** |
64 | * alloc_ep_req - returns a usb_request allocated by the gadget driver and |
65 | * allocates the request's buffer. |
66 | * |
67 | * @ep: the endpoint to allocate a usb_request |
68 | * @len: usb_requests's buffer suggested size |
69 | * |
70 | * In case @ep direction is OUT, the @len will be aligned to ep's |
71 | * wMaxPacketSize. In order to avoid memory leaks or drops, *always* use |
72 | * usb_requests's length (req->length) to refer to the allocated buffer size. |
73 | * Requests allocated via alloc_ep_req() *must* be freed by free_ep_req(). |
74 | */ |
75 | struct usb_request *alloc_ep_req(struct usb_ep *ep, size_t len); |
76 | |
77 | /* Frees a usb_request previously allocated by alloc_ep_req() */ |
78 | static inline void free_ep_req(struct usb_ep *ep, struct usb_request *req) |
79 | { |
80 | WARN_ON(req->buf == NULL); |
81 | kfree(objp: req->buf); |
82 | req->buf = NULL; |
83 | usb_ep_free_request(ep, req); |
84 | } |
85 | |
86 | #endif /* __U_F_H__ */ |
87 | |