From 5e0552018c2e8a0ef04417ee99095ebe43506e4b Mon Sep 17 00:00:00 2001
From: Hans Petter Selasky <hselasky@FreeBSD.org>
Date: Thu, 28 May 2020 08:05:46 +0000
Subject: [PATCH] Don't allow USB device drivers to parent own interface. It
 will prevent proper USB device detach.

MFC after:	3 days
Sponsored by:	Mellanox Technologies
---
 sys/dev/usb/usb_device.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sys/dev/usb/usb_device.c b/sys/dev/usb/usb_device.c
index 275914ed033..e4ed447b813 100644
--- a/sys/dev/usb/usb_device.c
+++ b/sys/dev/usb/usb_device.c
@@ -1402,7 +1402,7 @@ usbd_set_parent_iface(struct usb_device *udev, uint8_t iface_index,
 {
 	struct usb_interface *iface;
 
-	if (udev == NULL) {
+	if (udev == NULL || iface_index == parent_index) {
 		/* nothing to do */
 		return;
 	}