usb: dwc3: gadget: combine unaligned and zero flags

commit 1a22ec643580626f439c8583edafdcc73798f2fb upstream

Both flags are used for the same purpose in dwc3: appending an extra
TRB at the end to deal with controller requirements. By combining both
flags into one, we make it clear that the situation is the same and
that they should be treated equally.

Cc: Fei Yang <fei.yang@intel.com>
Cc: Sam Protsenko <semen.protsenko@linaro.org>
Cc: Felipe Balbi <balbi@kernel.org>
Cc: linux-usb@vger.kernel.org
Cc: stable@vger.kernel.org # 4.19.y
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
(cherry picked from commit 1a22ec643580626f439c8583edafdcc73798f2fb)
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/usb/dwc3/core.h

@@ -847,11 +847,11 @@ struct dwc3_hwparams {
  * @epnum: endpoint number to which this request refers
  * @trb: pointer to struct dwc3_trb
  * @trb_dma: DMA address of @trb
- * @unaligned: true for OUT endpoints with length not divisible by maxp
+ * @needs_extra_trb: true when request needs one extra TRB (either due to ZLP
+ *	or unaligned OUT)
  * @direction: IN or OUT direction flag
  * @mapped: true when request has been dma-mapped
  * @started: request is started
- * @zero: wants a ZLP
  */
 struct dwc3_request {
 	struct usb_request	request;
@@ -867,11 +867,10 @@ struct dwc3_request {
 	struct dwc3_trb		*trb;
 	dma_addr_t		trb_dma;
 
-	unsigned		unaligned:1;
+	unsigned		needs_extra_trb:1;
 	unsigned		direction:1;
 	unsigned		mapped:1;
 	unsigned		started:1;
-	unsigned		zero:1;
 };
 
 /*

drivers/usb/dwc3/gadget.c

@@ -1068,7 +1068,7 @@ static void dwc3_prepare_one_trb_sg(struct dwc3_ep *dep,
 			struct dwc3	*dwc = dep->dwc;
 			struct dwc3_trb	*trb;
 
-			req->unaligned = true;
+			req->needs_extra_trb = true;
 
 			/* prepare normal TRB */
 			dwc3_prepare_one_trb(dep, req, true, i);
@@ -1112,7 +1112,7 @@ static void dwc3_prepare_one_trb_linear(struct dwc3_ep *dep,
 		struct dwc3	*dwc = dep->dwc;
 		struct dwc3_trb	*trb;
 
-		req->unaligned = true;
+		req->needs_extra_trb = true;
 
 		/* prepare normal TRB */
 		dwc3_prepare_one_trb(dep, req, true, 0);
@@ -1128,7 +1128,7 @@ static void dwc3_prepare_one_trb_linear(struct dwc3_ep *dep,
 		struct dwc3	*dwc = dep->dwc;
 		struct dwc3_trb	*trb;
 
-		req->zero = true;
+		req->needs_extra_trb = true;
 
 		/* prepare normal TRB */
 		dwc3_prepare_one_trb(dep, req, true, 0);
@@ -1410,7 +1410,7 @@ static int dwc3_gadget_ep_dequeue(struct usb_ep *ep,
 					dwc3_ep_inc_deq(dep);
 				}
 
-				if (r->unaligned || r->zero) {
+				if (r->needs_extra_trb) {
 					trb = r->trb + r->num_pending_sgs + 1;
 					trb->ctrl &= ~DWC3_TRB_CTRL_HWO;
 					dwc3_ep_inc_deq(dep);
@@ -1421,7 +1421,7 @@ static int dwc3_gadget_ep_dequeue(struct usb_ep *ep,
 				trb->ctrl &= ~DWC3_TRB_CTRL_HWO;
 				dwc3_ep_inc_deq(dep);
 
-				if (r->unaligned || r->zero) {
+				if (r->needs_extra_trb) {
 					trb = r->trb + 1;
 					trb->ctrl &= ~DWC3_TRB_CTRL_HWO;
 					dwc3_ep_inc_deq(dep);
@@ -2250,7 +2250,8 @@ static int dwc3_gadget_ep_reclaim_completed_trb(struct dwc3_ep *dep,
 	 * with one TRB pending in the ring. We need to manually clear HWO bit
 	 * from that TRB.
 	 */
-	if ((req->zero || req->unaligned) && !(trb->ctrl & DWC3_TRB_CTRL_CHN)) {
+
+	if (req->needs_extra_trb && !(trb->ctrl & DWC3_TRB_CTRL_CHN)) {
 		trb->ctrl &= ~DWC3_TRB_CTRL_HWO;
 		return 1;
 	}
@@ -2327,11 +2328,10 @@ static int dwc3_gadget_ep_cleanup_completed_request(struct dwc3_ep *dep,
 		ret = dwc3_gadget_ep_reclaim_trb_linear(dep, req, event,
 				status);
 
-	if (req->unaligned || req->zero) {
+	if (req->needs_extra_trb) {
 		ret = dwc3_gadget_ep_reclaim_trb_linear(dep, req, event,
 				status);
-		req->unaligned = false;
-		req->zero = false;
+		req->needs_extra_trb = false;
 	}
 
 	req->request.actual = req->request.length - req->remaining;