From e42bd6a54b97e2a39b5004deac66a0fcd6ebbe75 Mon Sep 17 00:00:00 2001 From: Igor Kotrasinski Date: Tue, 15 Sep 2015 16:55:31 +0200 Subject: [PATCH] usb: gadget: dummy_hcd: fix rescan logic for transfer transfer() schedules a rescan for transfers larger than maxpacket, which is wrong for transfers that are multiples of maxpacket. Rewrite to fix and clarify packet multiple / remainder transfer logic. Signed-off-by: Igor Kotrasinski Signed-off-by: Felipe Balbi --- drivers/usb/gadget/udc/dummy_hcd.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/drivers/usb/gadget/udc/dummy_hcd.c b/drivers/usb/gadget/udc/dummy_hcd.c index 69a0b3fa4737..ab7e015e2f55 100644 --- a/drivers/usb/gadget/udc/dummy_hcd.c +++ b/drivers/usb/gadget/udc/dummy_hcd.c @@ -1385,12 +1385,15 @@ static int transfer(struct dummy_hcd *dum_hcd, struct urb *urb, if (len == 0) break; - /* use an extra pass for the final short packet */ - if (len > ep->ep.maxpacket) { - rescan = 1; - len -= (len % ep->ep.maxpacket); + /* send multiple of maxpacket first, then remainder */ + if (len >= ep->ep.maxpacket) { + is_short = 0; + if (len % ep->ep.maxpacket) + rescan = 1; + len -= len % ep->ep.maxpacket; + } else { + is_short = 1; } - is_short = (len % ep->ep.maxpacket) != 0; len = dummy_perform_transfer(urb, req, len); -- 2.45.2