From f035d139ffece7b6a7b8bfb17bd0ba715ee57a04 Mon Sep 17 00:00:00 2001
From: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Date: Fri, 12 Jan 2018 18:18:27 -0800
Subject: [PATCH] usb: dwc3: ep0: Reset TRB counter for ep0 IN
Git-commit: f035d139ffece7b6a7b8bfb17bd0ba715ee57a04
Patch-mainline: v4.16-rc3
References: bsc#1051510

DWC3 tracks TRB counter for each ep0 direction separately. In control
read transfer completion handler, the driver needs to reset the TRB
enqueue counter for ep0 IN direction. Currently the driver only resets
the TRB counter for control OUT endpoint. Check for the data direction
and properly reset the TRB counter from correct control endpoint.

Cc: stable@vger.kernel.org
Fixes: c2da2ff00606 ("usb: dwc3: ep0: don't use ep0in for transfers")
Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/usb/dwc3/ep0.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c
index 9c2e4a17918e..18be31d5743a 100644
--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -854,7 +854,12 @@ static void dwc3_ep0_complete_data(struct dwc3 *dwc,
 		trb++;
 		trb->ctrl &= ~DWC3_TRB_CTRL_HWO;
 		trace_dwc3_complete_trb(ep0, trb);
-		ep0->trb_enqueue = 0;
+
+		if (r->direction)
+			dwc->eps[1]->trb_enqueue = 0;
+		else
+			dwc->eps[0]->trb_enqueue = 0;
+
 		dwc->ep0_bounced = false;
 	}
 
-- 
2.18.0