From dca0119c3ab69fea2429ec2db7e3686614bd1439 Mon Sep 17 00:00:00 2001 From: John Youn Date: Thu, 19 May 2016 17:26:05 -0700 Subject: [PATCH] usb: dwc3: gadget: Simplify skipping of link TRBs Make the skipping of the link TRBS built-in to the increment operation. This simplifies the code wherever we increment the trb index and ensures that we never end up pointing to a link trb. Signed-off-by: John Youn Signed-off-by: Felipe Balbi --- drivers/usb/dwc3/gadget.c | 34 ++++++++++++++++------------------ 1 file changed, 16 insertions(+), 18 deletions(-) diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index f38db3b79d3f..24bb94258bb8 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -145,21 +145,29 @@ 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) +/** + * dwc3_ep_inc_trb() - Increment a TRB index. + * @index - Pointer to the TRB index to increment. + * + * The index should never point to the link TRB. After incrementing, + * if it is point to the link TRB, wrap around to the beginning. The + * link TRB is always at the last TRB entry. + */ +static void dwc3_ep_inc_trb(u8 *index) { - dep->trb_enqueue++; - dep->trb_enqueue %= DWC3_TRB_NUM; + (*index)++; + if (*index == (DWC3_TRB_NUM - 1)) + *index = 0; } -static void dwc3_ep_inc_deq(struct dwc3_ep *dep) +static void dwc3_ep_inc_enq(struct dwc3_ep *dep) { - dep->trb_dequeue++; - dep->trb_dequeue %= DWC3_TRB_NUM; + dwc3_ep_inc_trb(&dep->trb_enqueue); } -static int dwc3_ep_is_last_trb(unsigned int index) +static void dwc3_ep_inc_deq(struct dwc3_ep *dep) { - return index == DWC3_TRB_NUM - 1; + dwc3_ep_inc_trb(&dep->trb_dequeue); } void dwc3_gadget_giveback(struct dwc3_ep *dep, struct dwc3_request *req, @@ -172,13 +180,6 @@ void dwc3_gadget_giveback(struct dwc3_ep *dep, struct dwc3_request *req, i = 0; do { 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 (dwc3_ep_is_last_trb(dep->trb_dequeue)) - dwc3_ep_inc_deq(dep); } while(++i < req->request.num_mapped_sgs); req->started = false; } @@ -785,9 +786,6 @@ static void dwc3_prepare_one_trb(struct dwc3_ep *dep, } dwc3_ep_inc_enq(dep); - /* Skip the LINK-TRB */ - if (dwc3_ep_is_last_trb(dep->trb_enqueue)) - dwc3_ep_inc_enq(dep); trb->size = DWC3_TRB_SIZE_LENGTH(length); trb->bpl = lower_32_bits(dma); -- 2.20.1