From: Cristian Birsan <cristian.birsan@microchip.com>
Date: Thu, 12 Dec 2019 13:52:47 +0200
Subject: net: usb: lan78xx: Fix suspend/resume PHY register access error
Git-commit: 20032b63586ac6c28c936dff696981159913a13f
Patch-mainline: 5.5-rc3
References: networking-stable-19_12_28

Lan78xx driver accesses the PHY registers through MDIO bus over USB
connection. When performing a suspend/resume, the PHY registers can be
accessed before the USB connection is resumed. This will generate an
error and will prevent the device to resume correctly.
This patch adds the dependency between the MDIO bus and USB device to
allow correct handling of suspend/resume.

Fixes: ce85e13ad6ef ("lan78xx: Update to use phylib instead of mii_if_info.")
Signed-off-by: Cristian Birsan <cristian.birsan@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 drivers/net/usb/lan78xx.c |    1 +
 1 file changed, 1 insertion(+)

--- a/drivers/net/usb/lan78xx.c
+++ b/drivers/net/usb/lan78xx.c
@@ -1765,6 +1765,7 @@ static int lan78xx_mdio_init(struct lan7
 	dev->mdiobus->read = lan78xx_mdiobus_read;
 	dev->mdiobus->write = lan78xx_mdiobus_write;
 	dev->mdiobus->name = "lan78xx-mdiobus";
+	dev->mdiobus->parent = &dev->udev->dev;
 
 	snprintf(dev->mdiobus->id, MII_BUS_ID_SIZE, "usb-%03d:%03d",
 		 dev->udev->bus->busnum, dev->udev->devnum);