xhci driver claims it needs XHCI_TRUST_TX_LENGTH quirk for both Broadcom/Cavium and a Renesas xHC controllers.

The quirk was inteded for handling false "success" complete event for transfers that had data left untransferred. These transfers should complete with "short packet" events instead.

In these two new cases the false "success" completion is reported after a "short packet" if the TD consists of several TRBs. xHCI specs 4.10.1.1.2 say remaining TRBs should report "short packet" as well after the first short packet in a TD, but this issue seems so common it doesn't make sense to add the quirk for all vendors.

Turn these events into short packets automatically instead.

This gets rid of the "The WARN Successful completion on short TX for slot 1 ep 1: needs XHCI_TRUST_TX_LENGTH quirk" warning in many cases.

Cc: stable@vger.kernel.org Reported-by: Eli Billauer eli.billauer@gmail.com Reported-by: Ard Biesheuvel ardb@kernel.org Tested-by: Eli Billauer eli.billauer@gmail.com Tested-by: Ard Biesheuvel ardb@kernel.org Signed-off-by: Mathias Nyman mathias.nyman@linux.intel.com --- drivers/usb/host/xhci-ring.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index 9ebaa8e132a9..d23f7408c81f 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -2381,7 +2381,8 @@ static int handle_tx_event(struct xhci_hcd *xhci, case COMP_SUCCESS: if (EVENT_TRB_LEN(le32_to_cpu(event->transfer_len)) == 0) break; - if (xhci->quirks & XHCI_TRUST_TX_LENGTH) + if (xhci->quirks & XHCI_TRUST_TX_LENGTH || + ep_ring->last_td_was_short) trb_comp_code = COMP_SHORT_PACKET; else xhci_warn_ratelimited(xhci,