From 41ff4d6b62a90333ed70927f34bf7e076d851407 Mon Sep 17 00:00:00 2001
From: William Wu <william.wu@rock-chips.com>
Date: Fri, 27 Jul 2018 12:40:10 +0800
Subject: [PATCH] usb: dwc2: gadget: fix frame overrun issue

The frame_overrun flag is used to indicates
SOF number (current_frame) overrun in DSTS
and the target_frame over DSTS_SOFFN_LIMIT.

Clear the frame_overrun flag only if target_frame
below DSTS_SOFFN_LIMIT and current_frame less
than target_frame.

Change-Id: I91cf9001324a9bbbcc4bc28b335695d607fb69d4
Signed-off-by: William Wu <william.wu@rock-chips.com>
---
 drivers/usb/dwc2/gadget.c | 39 +++++++++++++++++++++------------------
 1 file changed, 21 insertions(+), 18 deletions(-)

diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
index a2dd5fe4553c..af21f44c2563 100644
--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -97,6 +97,23 @@ static inline bool using_dma(struct dwc2_hsotg *hsotg)
 	return hsotg->g_using_dma;
 }
 
+/**
+* dwc2_hsotg_read_frameno - read current frame number
+* @hsotg: The device instance
+*
+* Return the current frame number
+*/
+static u32 dwc2_hsotg_read_frameno(struct dwc2_hsotg *hsotg)
+{
+	u32 dsts;
+
+	dsts = dwc2_readl(hsotg->regs + DSTS);
+	dsts &= DSTS_SOFFN_MASK;
+	dsts >>= DSTS_SOFFN_SHIFT;
+
+	return dsts;
+}
+
 /**
  * dwc2_gadget_incr_frame_num - Increments the targeted frame number.
  * @hs_ep: The endpoint
@@ -107,11 +124,14 @@ static inline bool using_dma(struct dwc2_hsotg *hsotg)
  */
 static inline void dwc2_gadget_incr_frame_num(struct dwc2_hsotg_ep *hs_ep)
 {
+	struct dwc2_hsotg *hsotg = hs_ep->parent;
+	u32 current_frame = dwc2_hsotg_read_frameno(hsotg);
+
 	hs_ep->target_frame += hs_ep->interval;
 	if (hs_ep->target_frame > DSTS_SOFFN_LIMIT) {
 		hs_ep->frame_overrun = 1;
 		hs_ep->target_frame &= DSTS_SOFFN_LIMIT;
-	} else {
+	} else if (current_frame <= hs_ep->target_frame) {
 		hs_ep->frame_overrun = 0;
 	}
 }
@@ -524,23 +544,6 @@ static unsigned get_ep_limit(struct dwc2_hsotg_ep *hs_ep)
 	return maxsize;
 }
 
-/**
-* dwc2_hsotg_read_frameno - read current frame number
-* @hsotg: The device instance
-*
-* Return the current frame number
-*/
-static u32 dwc2_hsotg_read_frameno(struct dwc2_hsotg *hsotg)
-{
-	u32 dsts;
-
-	dsts = dwc2_readl(hsotg->regs + DSTS);
-	dsts &= DSTS_SOFFN_MASK;
-	dsts >>= DSTS_SOFFN_SHIFT;
-
-	return dsts;
-}
-
 /**
  * dwc2_hsotg_start_req - start a USB request from an endpoint's queue
  * @hsotg: The controller state.