net: stmmac: Disable PTP reference clock on error

If an error occurs while opening the device, make sure to disable the
PTP reference clock.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 7c38c9b..6060410 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -1754,6 +1754,13 @@ static int stmmac_hw_setup(struct net_device *dev, bool init_ptp)
 	return 0;
 }
 
+static void stmmac_hw_teardown(struct net_device *dev)
+{
+	struct stmmac_priv *priv = netdev_priv(dev);
+
+	clk_disable_unprepare(priv->plat->clk_ptp_ref);
+}
+
 /**
  *  stmmac_open - open entry point of the driver
  *  @dev : pointer to the device structure.
@@ -1863,6 +1870,7 @@ static int stmmac_open(struct net_device *dev)
 		phy_stop(dev->phydev);
 
 	del_timer_sync(&priv->txtimer);
+	stmmac_hw_teardown(dev);
 init_error:
 	free_dma_desc_resources(priv);
 dma_desc_error: