diff options
Diffstat (limited to 'drivers/usb/gadget/u_f.h')
| -rw-r--r-- | drivers/usb/gadget/u_f.h | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/drivers/usb/gadget/u_f.h b/drivers/usb/gadget/u_f.h index 21b75710c4a4..69a1d10df04f 100644 --- a/drivers/usb/gadget/u_f.h +++ b/drivers/usb/gadget/u_f.h @@ -47,8 +47,22 @@ struct usb_ep; struct usb_request; -/* Requests allocated via alloc_ep_req() must be freed by free_ep_req(). */ +/** + * 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); |