usb: dwc3: gadget: fix skip LINK_TRB on ISOC

When we reach to link trb, we just need to increase free_slot and then
calculate TRB. Return is not correct, as it will cause wrong TRB DMA
address to fetch in case of update transfer.

Cc: <stable@vger.kernel.org>
Signed-off-by: Pratyush Anand <pratyush.anand@st.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index e60e72c57663b5883ec5edbb4e311a995d5ca605..da8d57cb00e8108a9289fb9acc515dd1b1800e2d 100644 (file)
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -754,21 +754,18 @@ static void dwc3_prepare_one_trb(struct dwc3_ep *dep,
        struct dwc3             *dwc = dep->dwc;
        struct dwc3_trb         *trb;
 
-       unsigned int            cur_slot;
-
        dev_vdbg(dwc->dev, "%s: req %p dma %08llx length %d%s%s\n",
                        dep->name, req, (unsigned long long) dma,
                        length, last ? " last" : "",
                        chain ? " chain" : "");
 
-       trb = &dep->trb_pool[dep->free_slot & DWC3_TRB_MASK];
-       cur_slot = dep->free_slot;
-       dep->free_slot++;
-
        /* Skip the LINK-TRB on ISOC */
-       if (((cur_slot & DWC3_TRB_MASK) == DWC3_TRB_NUM - 1) &&
+       if (((dep->free_slot & DWC3_TRB_MASK) == DWC3_TRB_NUM - 1) &&
                        usb_endpoint_xfer_isoc(dep->endpoint.desc))
-               return;
+               dep->free_slot++;
+
+       trb = &dep->trb_pool[dep->free_slot & DWC3_TRB_MASK];
+       dep->free_slot++;
 
        if (!req->trb) {
                dwc3_gadget_move_request_queued(req);