From: Pawel Laszczak <pawell@xxxxxxxxxxx>
commit e913aada06830338633fb8524733b0ad3d38a7c1 upstream.
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>
Link: https://lore.kernel.org/r/20210623072728.41275-1-pawell@xxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Peter Chen <peter.chen@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/cdns3/cdnsp-ring.c | 18 ++++++++----------
1 file changed, 8 insertions(+), 10 deletions(-)
--- 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_dev
}
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_dev
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,
