Commit e913aada authored by Pawel Laszczak's avatar Pawel Laszczak Committed by Peter Chen
Browse files

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: <stable@vger.kernel.org>
Fixes: 3d829045 ("usb: cdnsp: cdns3 Add main part of Cadence USBSSP DRD Driver")
Signed-off-by: default avatarPawel Laszczak <pawell@cadence.com>
Link: https://lore.kernel.org/r/20210623072728.41275-1-pawell@gli-login.cadence.com


Signed-off-by: default avatarPeter Chen <peter.chen@kernel.org>
parent aa82f94e

drivers/usb/cdns3/cdnsp-ring.c

+8 −10
Original line number Diff line number Diff line
@@ -1932,16 +1932,14 @@ 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 {

			if (need_zero_pkt)

				zero_len_trb = !zero_len_trb;



			field &= ~TRB_CHAIN;

			field |= TRB_IOC;

			more_trbs_coming = false;

				need_zero_pkt = false;

			preq->td.last_trb = ring->enqueue;

		}

		}



		/* Only set interrupt on short packet for OUT endpoints. */

		if (!preq->direction)
@@ -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,