From: Pawel Laszczak <pawell@xxxxxxxxxxx> 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@xxxxxxxxxxxxxxx> Fixes: 3d82904559f4 ("usb: cdnsp: cdns3 Add main part of Cadence USBSSP DRD Driver") Signed-off-by: Pawel Laszczak <pawell@xxxxxxxxxxx> --- drivers/usb/cdns3/cdnsp-ring.c | 18 ++++++++---------- 1 file changed, 8 insertions(+), 10 deletions(-) diff --git a/drivers/usb/cdns3/cdnsp-ring.c b/drivers/usb/cdns3/cdnsp-ring.c index 68972746e363..1b1438457fb0 100644 --- 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, -- 2.25.1