[PATCH v6 1/2] usb: dwc3: gadget: Execute gadget stop after halting the controller

[Wesley Cheng]

Do not call gadget stop until the poll for controller halt is
completed.  DEVTEN is cleared as part of gadget stop, so the intention to
allow ep0 events to continue while waiting for controller halt is not
happening.

Fixes: c96683798e27 ("usb: dwc3: ep0: Don't prepare beyond Setup stage")
Cc: stable@xxxxxxxxxxxxxxx
Acked-by: Thinh Nguyen <Thinh.Nguyen@xxxxxxxxxxxx>
Signed-off-by: Wesley Cheng <quic_wcheng@xxxxxxxxxxx>
---
 drivers/usb/dwc3/gadget.c | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 9f492c8a7d0b..dd6057bad37e 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -2637,7 +2637,6 @@ static int dwc3_gadget_soft_disconnect(struct dwc3 *dwc)
 	 * bit.
 	 */
 	dwc3_stop_active_transfers(dwc);
-	__dwc3_gadget_stop(dwc);
 	spin_unlock_irqrestore(&dwc->lock, flags);
 
 	/*
@@ -2674,7 +2673,19 @@ static int dwc3_gadget_soft_disconnect(struct dwc3 *dwc)
 	 * remaining event generated by the controller while polling for
 	 * DSTS.DEVCTLHLT.
 	 */
-	return dwc3_gadget_run_stop(dwc, false);
+	ret = dwc3_gadget_run_stop(dwc, false);
+
+	/*
+	 * Stop the gadget after controller is halted, so that if needed, the
+	 * events to update EP0 state can still occur while the run/stop
+	 * routine polls for the halted state.  DEVTEN is cleared as part of
+	 * gadget stop.
+	 */
+	spin_lock_irqsave(&dwc->lock, flags);
+	__dwc3_gadget_stop(dwc);
+	spin_unlock_irqrestore(&dwc->lock, flags);
+
+	return ret;
 }
 
 static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)