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| author | Michael Grzeschik <m.grzeschik@pengutronix.de> | 2024-09-01 21:11:16 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-09-03 09:57:08 +0200 |
| commit | d9c61bb33fbbcbc2d5f69efa10db116dab4b56cc (patch) | |
| tree | 61fe9206f2bfa5b9b58167a28e4fbbb5f13eb4ae /include/linux/usb/func_utils.h | |
| parent | f20998f23a8ce3ba56a06d9423ee57e92bae298c (diff) | |
| download | lwn-d9c61bb33fbbcbc2d5f69efa10db116dab4b56cc.tar.gz lwn-d9c61bb33fbbcbc2d5f69efa10db116dab4b56cc.zip | |
usb: gadget: function: move u_f.h to include/linux/usb/func_utils.h
We move the func_utils.h header to include/linux/usb to be
able to compile function drivers outside of the
drivers/usb/gadget/function directory.
Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Link: https://lore.kernel.org/r/20240116-ml-topic-u9p-v12-1-9a27de5160e0@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include/linux/usb/func_utils.h')
| -rw-r--r-- | include/linux/usb/func_utils.h | 86 |
1 files changed, 86 insertions, 0 deletions
diff --git a/include/linux/usb/func_utils.h b/include/linux/usb/func_utils.h new file mode 100644 index 000000000000..c8795c965109 --- /dev/null +++ b/include/linux/usb/func_utils.h @@ -0,0 +1,86 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * func_utils.h + * + * Utility definitions for USB functions + * + * Copyright (c) 2013 Samsung Electronics Co., Ltd. + * http://www.samsung.com + * + * Author: Andrzej Pietrasiewicz <andrzejtp2010@gmail.com> + */ + +#ifndef _FUNC_UTILS_H_ +#define _FUNC_UTILS_H_ + +#include <linux/usb/gadget.h> +#include <linux/overflow.h> + +/* Variable Length Array Macros **********************************************/ +#define vla_group(groupname) size_t groupname##__next = 0 +#define vla_group_size(groupname) groupname##__next + +#define vla_item(groupname, type, name, n) \ + size_t groupname##_##name##__offset = ({ \ + size_t offset = 0; \ + if (groupname##__next != SIZE_MAX) { \ + size_t align_mask = __alignof__(type) - 1; \ + size_t size = array_size(n, sizeof(type)); \ + offset = (groupname##__next + align_mask) & \ + ~align_mask; \ + if (check_add_overflow(offset, size, \ + &groupname##__next)) { \ + groupname##__next = SIZE_MAX; \ + offset = 0; \ + } \ + } \ + offset; \ + }) + +#define vla_item_with_sz(groupname, type, name, n) \ + size_t groupname##_##name##__sz = array_size(n, sizeof(type)); \ + size_t groupname##_##name##__offset = ({ \ + size_t offset = 0; \ + if (groupname##__next != SIZE_MAX) { \ + size_t align_mask = __alignof__(type) - 1; \ + offset = (groupname##__next + align_mask) & \ + ~align_mask; \ + if (check_add_overflow(offset, groupname##_##name##__sz,\ + &groupname##__next)) { \ + groupname##__next = SIZE_MAX; \ + offset = 0; \ + } \ + } \ + offset; \ + }) + +#define vla_ptr(ptr, groupname, name) \ + ((void *) ((char *)ptr + groupname##_##name##__offset)) + +struct usb_ep; +struct usb_request; + +/** + * alloc_ep_req - returns a usb_request allocated by the gadget driver and + * allocates the request's buffer. + * + * @ep: the endpoint to allocate a usb_request + * @len: usb_requests's buffer suggested size + * + * In case @ep direction is OUT, the @len will be aligned to ep's + * wMaxPacketSize. In order to avoid memory leaks or drops, *always* use + * usb_requests's length (req->length) to refer to the allocated buffer size. + * Requests allocated via alloc_ep_req() *must* be freed by free_ep_req(). + */ +struct usb_request *alloc_ep_req(struct usb_ep *ep, size_t len); + +/* Frees a usb_request previously allocated by alloc_ep_req() */ +static inline void free_ep_req(struct usb_ep *ep, struct usb_request *req) +{ + WARN_ON(req->buf == NULL); + kfree(req->buf); + req->buf = NULL; + usb_ep_free_request(ep, req); +} + +#endif /* _FUNC_UTILS_H_ */ |