usb: dwc3: gadget: add trb enqueue/dequeue helpers

[cascardo/linux.git] / drivers / usb / dwc3 / gadget.c

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 0e7cc20..98d8a45 100644 (file)
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -145,6 +145,21 @@ int dwc3_gadget_set_link_state(struct dwc3 *dwc, enum dwc3_link_state state)
        return -ETIMEDOUT;
 }
 
+static void dwc3_ep_inc_enq(struct dwc3_ep *dep)
+{
+       dep->trb_enqueue++;
+}
+
+static void dwc3_ep_inc_deq(struct dwc3_ep *dep)
+{
+       dep->trb_dequeue++;
+}
+
+static int dwc3_ep_is_last_trb(unsigned int index)
+{
+       return (index % DWC3_TRB_NUM) == (DWC3_TRB_NUM - 1);
+}
+
 void dwc3_gadget_giveback(struct dwc3_ep *dep, struct dwc3_request *req,
                int status)
 {
@@ -154,16 +169,15 @@ void dwc3_gadget_giveback(struct dwc3_ep *dep, struct dwc3_request *req,
        if (req->started) {
                i = 0;
                do {
-                       dep->trb_dequeue++;
+                       dwc3_ep_inc_deq(dep);
                        /*
                         * Skip LINK TRB. We can't use req->trb and check for
                         * DWC3_TRBCTL_LINK_TRB because it points the TRB we
                         * just completed (not the LINK TRB).
                         */
-                       if (((dep->trb_dequeue % DWC3_TRB_NUM) ==
-                               DWC3_TRB_NUM - 1) &&
+                       if (dwc3_ep_is_last_trb(dep->trb_dequeue) &&
                                usb_endpoint_xfer_isoc(dep->endpoint.desc))
-                               dep->trb_dequeue++;
+                               dwc3_ep_inc_deq(dep);
                } while(++i < req->request.num_mapped_sgs);
                req->started = false;
        }
@@ -750,11 +764,11 @@ static void dwc3_prepare_one_trb(struct dwc3_ep *dep,
                req->first_trb_index = dep->trb_enqueue % DWC3_TRB_NUM;
        }
 
-       dep->trb_enqueue++;
+       dwc3_ep_inc_enq(dep);
        /* Skip the LINK-TRB on ISOC */
-       if (((dep->trb_enqueue % DWC3_TRB_NUM) == DWC3_TRB_NUM - 1) &&
+       if (dwc3_ep_is_last_trb(dep->trb_enqueue) &&
                        usb_endpoint_xfer_isoc(dep->endpoint.desc))
-               dep->trb_enqueue++;
+               dwc3_ep_inc_enq(dep);
 
        trb->size = DWC3_TRB_SIZE_LENGTH(length);
        trb->bpl = lower_32_bits(dma);