fotg210-udc: Complete OUT requests on short packets

[ Upstream commit 75bb93be0027123b5db6cbcce89eb62f0f6b3c5b ]

A short packet indicates the end of a transfer and marks the request as
complete.

Fixes: b84a8dee23fd ("usb: gadget: add Faraday fotg210_udc driver")
Signed-off-by: Fabian Vogt <fabian@ritter-vogt.de>
Link: https://lore.kernel.org/r/20210324141115.9384-8-fabian@ritter-vogt.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/usb/gadget/udc/fotg210-udc.c b/drivers/usb/gadget/udc/fotg210-udc.c
index 9925d7ac9138d409ae94b5eb2daa2550e4d7b535..75bf446f4a666af2beecc6796361bb9780b15db9 100644 (file)
--- a/drivers/usb/gadget/udc/fotg210-udc.c
+++ b/drivers/usb/gadget/udc/fotg210-udc.c
@@ -849,12 +849,16 @@ static void fotg210_out_fifo_handler(struct fotg210_ep *ep)
 {
        struct fotg210_request *req = list_entry(ep->queue.next,
                                                 struct fotg210_request, queue);
+       int disgr1 = ioread32(ep->fotg210->reg + FOTG210_DISGR1);
 
        fotg210_start_dma(ep, req);
 
-       /* finish out transfer */
+       /* Complete the request when it's full or a short packet arrived.
+        * Like other drivers, short_not_ok isn't handled.
+        */
+
        if (req->req.length == req->req.actual ||
-           req->req.actual < ep->ep.maxpacket)
+           (disgr1 & DISGR1_SPK_INT(ep->epnum - 1)))
                fotg210_done(ep, req, 0);
 }