dwc_otg: Enable NAK holdoff for control split transactions

Certain low-speed devices take a very long time to complete a
data or status stage of a control transaction, producing NAK
responses until they complete internal processing - the USB2.0
spec limit is up to 500mS. This causes the same type of interrupt
storm as seen with USB-serial dongles prior to c8edb238.

In certain circumstances, usually while booting, this interrupt
storm could cause SD card timeouts.

diff --git a/drivers/usb/host/dwc_otg/dwc_otg_hcd_intr.c b/drivers/usb/host/dwc_otg/dwc_otg_hcd_intr.c
index 19abea006093ce7a2bbfc04e3dc6ccce3a7562f9..509b629f1e229f9dec9806e0418504637ca7d08c 100644 (file)
--- a/drivers/usb/host/dwc_otg/dwc_otg_hcd_intr.c
+++ b/drivers/usb/host/dwc_otg/dwc_otg_hcd_intr.c
@@ -1857,8 +1857,7 @@ static int32_t handle_hc_nak_intr(dwc_otg_hcd_t * hcd,
         */
        switch(dwc_otg_hcd_get_pipe_type(&qtd->urb->pipe_info)) {
                case UE_BULK:
-               //case UE_INTERRUPT:
-               //case UE_CONTROL:
+               case UE_CONTROL:
                if (nak_holdoff_enable)
                        hc->qh->nak_frame = dwc_otg_hcd_get_frame_number(hcd);
        }