[linux-2.6-block.git] / drivers / usb / gadget / u_f.h

// SPDX-License-Identifier: GPL-2.0
/*
 * u_f.h
 *
 * Utility definitions for USB functions
 *
 * Copyright (c) 2013 Samsung Electronics Co., Ltd.
 *		http://www.samsung.com
 *
 * Author: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
 */

#ifndef __U_F_H__
#define __U_F_H__

#include <linux/usb/gadget.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 align_mask = __alignof__(type) - 1;		       \
		size_t offset = (groupname##__next + align_mask) & ~align_mask;\
		size_t size = (n) * sizeof(type);			       \
		groupname##__next = offset + size;			       \
		offset;							       \
	})

#define vla_item_with_sz(groupname, type, name, n) \
	size_t groupname##_##name##__sz = (n) * sizeof(type);		       \
	size_t groupname##_##name##__offset = ({			       \
		size_t align_mask = __alignof__(type) - 1;		       \
		size_t offset = (groupname##__next + align_mask) & ~align_mask;\
		size_t size = groupname##_##name##__sz;			       \
		groupname##__next = offset + size;			       \
		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 /* __U_F_H__ */
Commit	Line	Data
5fd54ace	1	// SPDX-License-Identifier: GPL-2.0
1efd54ea AP	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 <andrzej.p@samsung.com>
1efd54ea AP	11	*/
	12
	13	#ifndef __U_F_H__
	14	#define __U_F_H__
	15
079fe5a6 FT	16	#include <linux/usb/gadget.h>
079fe5a6 FT	17
74d48466 AP	18	/* Variable Length Array Macros **********************************************/
	19	#define vla_group(groupname) size_t groupname##__next = 0
	20	#define vla_group_size(groupname) groupname##__next
	21
	22	#define vla_item(groupname, type, name, n) \
	23	size_t groupname##_##name##__offset = ({ \
	24	size_t align_mask = __alignof__(type) - 1; \
	25	size_t offset = (groupname##__next + align_mask) & ~align_mask;\
	26	size_t size = (n) * sizeof(type); \
	27	groupname##__next = offset + size; \
	28	offset; \
	29	})
	30
	31	#define vla_item_with_sz(groupname, type, name, n) \
	32	size_t groupname##_##name##__sz = (n) * sizeof(type); \
	33	size_t groupname##_##name##__offset = ({ \
	34	size_t align_mask = __alignof__(type) - 1; \
	35	size_t offset = (groupname##__next + align_mask) & ~align_mask;\
	36	size_t size = groupname##_##name##__sz; \
	37	groupname##__next = offset + size; \
	38	offset; \
	39	})
	40
	41	#define vla_ptr(ptr, groupname, name) \
	42	((void ) ((char )ptr + groupname##_##name##__offset))
	43
1efd54ea AP	44	struct usb_ep;
	45	struct usb_request;
	46
e0466156 FT	47	/**
	48	* alloc_ep_req - returns a usb_request allocated by the gadget driver and
	49	* allocates the request's buffer.
	50	*
	51	* @ep: the endpoint to allocate a usb_request
	52	* @len: usb_requests's buffer suggested size
e0466156 FT	53	*
	54	* In case @ep direction is OUT, the @len will be aligned to ep's
	55	* wMaxPacketSize. In order to avoid memory leaks or drops, always use
	56	* usb_requests's length (req->length) to refer to the allocated buffer size.
	57	* Requests allocated via alloc_ep_req() must be freed by free_ep_req().
	58	*/
aadbe812	59	struct usb_request alloc_ep_req(struct usb_ep ep, size_t len);
e0466156 FT	60
e0466156 FT	61	/* Frees a usb_request previously allocated by alloc_ep_req() */
079fe5a6 FT	62	static inline void free_ep_req(struct usb_ep ep, struct usb_request req)
079fe5a6 FT	63	{
7fafcfdf	64	WARN_ON(req->buf == NULL);
079fe5a6	65	kfree(req->buf);
7fafcfdf	66	req->buf = NULL;
079fe5a6 FT	67	usb_ep_free_request(ep, req);
079fe5a6 FT	68	}
1efd54ea AP	69
1efd54ea AP	70	#endif /* __U_F_H__ */