From 66004381661386d14183a436c5e0caeb19f4b415 Mon Sep 17 00:00:00 2001
From: Patrick Delaunay <patrick.delaunay@st.com>
Date: Mon, 27 Apr 2020 15:30:00 +0200
Subject: [PATCH] usb: host: dwc2: force reset assert

Assert reset before deassert in dwc2_reset;
this patch solve issues when the DWC2 registers are already
initialized with value incompatible with host mode.

Force a hardware reset of the IP reset all the DWC2 registers at
default value, the host driver start with a clean state
(Core Soft reset doen in dwc_otg_core_reset is not enought
 to reset all register).

The error can occurs in U-Boot when DWC2 device gadget driver
force device mode (called by ums or dfu command, before to execute
the usb start command).

Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
---
 drivers/usb/host/dwc2.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/usb/host/dwc2.c b/drivers/usb/host/dwc2.c
index b1b79d0a18..640ae3e730 100644
--- a/drivers/usb/host/dwc2.c
+++ b/drivers/usb/host/dwc2.c
@@ -1151,6 +1151,8 @@ static int dwc2_reset(struct udevice *dev)
 			return ret;
 	}
 
+	/* force reset to clear all IP register */
+	reset_assert_bulk(&priv->resets);
 	ret = reset_deassert_bulk(&priv->resets);
 	if (ret) {
 		reset_release_bulk(&priv->resets);
-- 
2.39.5