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From 3d8a3a5cbcd4d36768cf53e778d8165aefabd5b0 Mon Sep 17 00:00:00 2001
From: P33M <P33M@github.com>
Date: Fri, 20 Sep 2013 16:08:27 +0100
Subject: [PATCH 093/174] 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.
---
 drivers/usb/host/dwc_otg/dwc_otg_hcd_intr.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

--- 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_ot
 	 */
 	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);
 	}