usb: mtu3: fix uncontinuous SeqN issue after disable EP

Reset EP when disable it to reset data toggle for U2 EP, and
SeqN, flow control status etc for U3 EP, this can avoid
issue of uncontinuous SeqN

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/mtu3/mtu3_core.c

@@ -195,6 +195,16 @@ static void mtu3_intr_enable(struct mtu3 *mtu)
 	mtu3_writel(mbase, U3D_DEV_LINK_INTR_ENABLE, SSUSB_DEV_SPEED_CHG_INTR);
 }
 
+/* reset: u2 - data toggle, u3 - SeqN, flow control status etc */
+static void mtu3_ep_reset(struct mtu3_ep *mep)
+{
+	struct mtu3 *mtu = mep->mtu;
+	u32 rst_bit = EP_RST(mep->is_in, mep->epnum);
+
+	mtu3_setbits(mtu->mac_base, U3D_EP_RST, rst_bit);
+	mtu3_clrbits(mtu->mac_base, U3D_EP_RST, rst_bit);
+}
+
 /* set/clear the stall and toggle bits for non-ep0 */
 void mtu3_ep_stall_set(struct mtu3_ep *mep, bool set)
 {
@@ -220,8 +230,7 @@ void mtu3_ep_stall_set(struct mtu3_ep *mep, bool set)
 	}
 
 	if (!set) {
-		mtu3_setbits(mbase, U3D_EP_RST, EP_RST(mep->is_in, epnum));
-		mtu3_clrbits(mbase, U3D_EP_RST, EP_RST(mep->is_in, epnum));
+		mtu3_ep_reset(mep);
 		mep->flags &= ~MTU3_EP_STALL;
 	} else {
 		mep->flags |= MTU3_EP_STALL;
@@ -400,6 +409,7 @@ void mtu3_deconfig_ep(struct mtu3 *mtu, struct mtu3_ep *mep)
 		mtu3_setbits(mbase, U3D_QIECR0, QMU_RX_DONE_INT(epnum));
 	}
 
+	mtu3_ep_reset(mep);
 	ep_fifo_free(mep);
 
 	dev_dbg(mtu->dev, "%s: %s\n", __func__, mep->name);