diff options
Diffstat (limited to 'drivers/usb/gadget/u_f.h')
| -rw-r--r-- | drivers/usb/gadget/u_f.h | 26 |
1 files changed, 23 insertions, 3 deletions
diff --git a/drivers/usb/gadget/u_f.h b/drivers/usb/gadget/u_f.h index 1d5f0eb68552..69a1d10df04f 100644 --- a/drivers/usb/gadget/u_f.h +++ b/drivers/usb/gadget/u_f.h @@ -16,6 +16,8 @@ #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 @@ -45,8 +47,26 @@ struct usb_ep; struct usb_request; -struct usb_request *alloc_ep_req(struct usb_ep *ep, int len, int default_len); - -#endif /* __U_F_H__ */ +/** + * 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 + * @default_len: used if @len is not provided, ie, is 0 + * + * 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, int default_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) +{ + kfree(req->buf); + usb_ep_free_request(ep, req); +} +#endif /* __U_F_H__ */ |