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From 7cc73feb57f6d8f4b06c238608db265cc610c483 Mon Sep 17 00:00:00 2001
From: Trevor Woerner <twoerner@gmail.com>
Date: Sun, 24 Oct 2021 13:50:02 -0400
Subject: [PATCH] net: nxp: lpc_eth.c: avoid hang when bringing interface down
Git-commit: ace19b992436a257d9a793672e57abc28fe83e2e
Patch-mainline: v5.15
References: stable-5.14.16

commit ace19b992436a257d9a793672e57abc28fe83e2e upstream.

A hard hang is observed whenever the ethernet interface is brought
down. If the PHY is stopped before the LPC core block is reset,
the SoC will hang. Comparing lpc_eth_close() and lpc_eth_open() I
re-arranged the ordering of the functions calls in lpc_eth_close() to
reset the hardware before stopping the PHY.

Fixes: b7370112f519 ("lpc32xx: Added ethernet driver")
Signed-off-by: Trevor Woerner <twoerner@gmail.com>
Acked-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/net/ethernet/nxp/lpc_eth.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/nxp/lpc_eth.c b/drivers/net/ethernet/nxp/lpc_eth.c
index 64c6842bd452..6d8406cfd38a 100644
--- a/drivers/net/ethernet/nxp/lpc_eth.c
+++ b/drivers/net/ethernet/nxp/lpc_eth.c
@@ -1015,9 +1015,6 @@ static int lpc_eth_close(struct net_device *ndev)
 	napi_disable(&pldat->napi);
 	netif_stop_queue(ndev);
 
-	if (ndev->phydev)
-		phy_stop(ndev->phydev);
-
 	spin_lock_irqsave(&pldat->lock, flags);
 	__lpc_eth_reset(pldat);
 	netif_carrier_off(ndev);
@@ -1025,6 +1022,8 @@ static int lpc_eth_close(struct net_device *ndev)
 	writel(0, LPC_ENET_MAC2(pldat->net_base));
 	spin_unlock_irqrestore(&pldat->lock, flags);
 
+	if (ndev->phydev)
+		phy_stop(ndev->phydev);
 	clk_disable_unprepare(pldat->clk);
 
 	return 0;
-- 
2.26.2