usb: cdnsp: Fixed issue with ZLP

The condition "if (need_zero_pkt && zero_len_trb)" was always false and it caused that TRB for ZLP was not prepared. Fix causes that after preparing last TRB in TD, the driver prepares additional TD with ZLP when a ZLP is required. Cc: <[email protected]> Fixes: 3d82904 ("usb: cdnsp: cdns3 Add main part of Cadence USBSSP DRD Driver") Signed-off-by: Pawel Laszczak <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Peter Chen <[email protected]>
pop-os · Jul 29, 2021 · e913aad · e913aad
1 parent aa82f94
commit e913aad
Showing 1 changed file with 8 additions and 10 deletions.
diff --git a/drivers/usb/cdns3/cdnsp-ring.c b/drivers/usb/cdns3/cdnsp-ring.c
@@ -1932,15 +1932,13 @@ int cdnsp_queue_bulk_tx(struct cdnsp_device *pdev, struct cdnsp_request *preq)
 		}
 
 		if (enqd_len + trb_buff_len >= full_len) {
-			if (need_zero_pkt && zero_len_trb) {
-				zero_len_trb = true;
-			} else {
-				field &= ~TRB_CHAIN;
-				field |= TRB_IOC;
-				more_trbs_coming = false;
-				need_zero_pkt = false;
-				preq->td.last_trb = ring->enqueue;
-			}
+			if (need_zero_pkt)
+				zero_len_trb = !zero_len_trb;
+
+			field &= ~TRB_CHAIN;
+			field |= TRB_IOC;
+			more_trbs_coming = false;
+			preq->td.last_trb = ring->enqueue;
 		}
 
 		/* Only set interrupt on short packet for OUT endpoints. */
@@ -1955,7 +1953,7 @@ int cdnsp_queue_bulk_tx(struct cdnsp_device *pdev, struct cdnsp_request *preq)
 		length_field = TRB_LEN(trb_buff_len) | TRB_TD_SIZE(remainder) |
 			TRB_INTR_TARGET(0);
 
-		cdnsp_queue_trb(pdev, ring, more_trbs_coming | need_zero_pkt,
+		cdnsp_queue_trb(pdev, ring, more_trbs_coming | zero_len_trb,
 				lower_32_bits(send_addr),
 				upper_32_bits(send_addr),
 				length_field,