usb: cdns3: gadget: using correct sg operations

It needs to use request->num_mapped_sgs to indicate mapped sg number,
the request->num_sgs is the sg number before the mapping. These two
entries have different values for the platforms which iommu or
swiotlb is used. Besides, it needs to use correct sg APIs for
mapped sg list for TRB assignment.
Signed-off-by: NPeter Chen <peter.chen@nxp.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

drivers/usb/cdns3/gadget.c

@@ -1098,11 +1098,13 @@ static int cdns3_ep_run_transfer(struct cdns3_endpoint *priv_ep,
 	u32 control;
 	int pcs;
 	u16 total_tdl = 0;
+	struct scatterlist *s = NULL;
+	bool sg_supported = !!(request->num_mapped_sgs);
 
 	if (priv_ep->type == USB_ENDPOINT_XFER_ISOC)
 		num_trb = priv_ep->interval;
 	else
-		num_trb = request->num_sgs ? request->num_sgs : 1;
+		num_trb = sg_supported ? request->num_mapped_sgs : 1;
 
 	if (num_trb > priv_ep->free_trbs) {
 		priv_ep->flags |= EP_RING_FULL;
@@ -1162,6 +1164,9 @@ static int cdns3_ep_run_transfer(struct cdns3_endpoint *priv_ep,
 	if (priv_dev->dev_ver <= DEV_VER_V2)
 		togle_pcs = cdns3_wa1_update_guard(priv_ep, trb);
 
+	if (sg_supported)
+		s = request->sg;
+
 	/* set incorrect Cycle Bit for first trb*/
 	control = priv_ep->pcs ? 0 : TRB_CYCLE;
 
@@ -1171,13 +1176,13 @@ static int cdns3_ep_run_transfer(struct cdns3_endpoint *priv_ep,
 
 		/* fill TRB */
 		control |= TRB_TYPE(TRB_NORMAL);
-		trb->buffer = cpu_to_le32(TRB_BUFFER(request->num_sgs == 0
-				? trb_dma : request->sg[sg_iter].dma_address));
-
-		if (likely(!request->num_sgs))
+		if (sg_supported) {
+			trb->buffer = cpu_to_le32(TRB_BUFFER(sg_dma_address(s)));
+			length = sg_dma_len(s);
+		} else {
+			trb->buffer = cpu_to_le32(TRB_BUFFER(trb_dma));
 			length = request->length;
-		else
-			length = request->sg[sg_iter].length;
+		}
 
 		if (likely(priv_dev->dev_ver >= DEV_VER_V2))
 			td_size = DIV_ROUND_UP(length,
@@ -1215,6 +1220,9 @@ static int cdns3_ep_run_transfer(struct cdns3_endpoint *priv_ep,
 		else
 			priv_req->trb->control = cpu_to_le32(control);
 
+		if (sg_supported)
+			s = sg_next(s);
+
 		control = 0;
 		++sg_iter;
 		priv_req->end_trb = priv_ep->enqueue;