usb: dwc3: gadget: move % operation to increment helpers

By moving our % DWC3_NUM_TRB operation to the
increment helpers, the rest of the driver can be
simplified.

It's also a good practice to make sure we will have
a single place dealing with details about how to
increment our enqueue and dequeue pointers.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 98d8a4549103a1f182c2108c6b8f61aa2973d0a7..6c5eb0c596961d213d5824f9f8a7380cfd5dade1 100644 (file)
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -148,16 +148,18 @@ int dwc3_gadget_set_link_state(struct dwc3 *dwc, enum dwc3_link_state state)
 static void dwc3_ep_inc_enq(struct dwc3_ep *dep)
 {
        dep->trb_enqueue++;
+       dep->trb_enqueue %= DWC3_TRB_NUM;
 }
 
 static void dwc3_ep_inc_deq(struct dwc3_ep *dep)
 {
        dep->trb_dequeue++;
+       dep->trb_dequeue %= DWC3_TRB_NUM;
 }
 
 static int dwc3_ep_is_last_trb(unsigned int index)
 {
-       return (index % DWC3_TRB_NUM) == (DWC3_TRB_NUM - 1);
+       return index == DWC3_TRB_NUM - 1;
 }
 
 void dwc3_gadget_giveback(struct dwc3_ep *dep, struct dwc3_request *req,
@@ -755,13 +757,13 @@ static void dwc3_prepare_one_trb(struct dwc3_ep *dep,
                        chain ? " chain" : "");
 
 
-       trb = &dep->trb_pool[dep->trb_enqueue % DWC3_TRB_NUM];
+       trb = &dep->trb_pool[dep->trb_enqueue];
 
        if (!req->trb) {
                dwc3_gadget_move_started_request(req);
                req->trb = trb;
                req->trb_dma = dwc3_trb_dma_offset(dep, trb);
-               req->first_trb_index = dep->trb_enqueue % DWC3_TRB_NUM;
+               req->first_trb_index = dep->trb_enqueue;
        }
 
        dwc3_ep_inc_enq(dep);
@@ -840,11 +842,11 @@ static void dwc3_prepare_trbs(struct dwc3_ep *dep, bool starting)
        BUILD_BUG_ON_NOT_POWER_OF_2(DWC3_TRB_NUM);
 
        /* the first request must not be queued */
-       trbs_left = (dep->trb_dequeue - dep->trb_enqueue) % DWC3_TRB_NUM;
+       trbs_left = dep->trb_dequeue - dep->trb_enqueue;
 
        /* Can't wrap around on a non-isoc EP since there's no link TRB */
        if (!usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
-               max = DWC3_TRB_NUM - (dep->trb_enqueue % DWC3_TRB_NUM);
+               max = DWC3_TRB_NUM - dep->trb_enqueue;
                if (trbs_left > max)
                        trbs_left = max;
        }