[PATCH net-next 15/16] net: stmmac: Add dedicated XPCS cleanup method

[Serge Semin]

Currently the XPCS handler destruction is performed in the
stmmac_mdio_unregister() method. It doesn't look well because the handler
isn't originally created in the corresponding protagonist
stmmac_mdio_unregister(), but in the stmmac_xpcs_setup() function. In
order to have a bit more coherent MDIO and XPCS setup/cleanup procedures
let's move the DW XPCS destruction to the dedicated stmmac_xpcs_clean()
method.

Note besides of that this change is a preparation to adding the PCS device
supplied by means of the "pcs-handle" property. It's required since DW
XPCS IP-core can be synthesized embedded into the chip with directly
accessible CSRs. In that case the SMA interface can be absent so no
corresponding MDIO bus will be registered.

Signed-off-by: Serge Semin <fancer.lancer@xxxxxxxxx>
---
 drivers/net/ethernet/stmicro/stmmac/stmmac.h      |  1 +
 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c |  6 +++++-
 drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c | 14 +++++++++++---
 3 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac.h b/drivers/net/ethernet/stmicro/stmmac/stmmac.h
index d8a1c84880c5..1709de519813 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac.h
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac.h
@@ -344,6 +344,7 @@ int stmmac_mdio_unregister(struct net_device *ndev);
 int stmmac_mdio_register(struct net_device *ndev);
 int stmmac_mdio_reset(struct mii_bus *mii);
 int stmmac_xpcs_setup(struct net_device *ndev);
+void stmmac_xpcs_clean(struct net_device *ndev);
 void stmmac_set_ethtool_ops(struct net_device *netdev);
 
 int stmmac_init_tstamp_counter(struct stmmac_priv *priv, u32 systime_flags);
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index c3641db00f96..379552240ac9 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -7639,8 +7639,9 @@ int stmmac_dvr_probe(struct device *device,
 
 error_netdev_register:
 	phylink_destroy(priv->phylink);
-error_xpcs_setup:
 error_phy_setup:
+	stmmac_xpcs_clean(ndev);
+error_xpcs_setup:
 	if (priv->hw->pcs != STMMAC_PCS_TBI &&
 	    priv->hw->pcs != STMMAC_PCS_RTBI)
 		stmmac_mdio_unregister(ndev);
@@ -7682,6 +7683,9 @@ void stmmac_dvr_remove(struct device *dev)
 	if (priv->plat->stmmac_rst)
 		reset_control_assert(priv->plat->stmmac_rst);
 	reset_control_assert(priv->plat->stmmac_ahb_rst);
+
+	stmmac_xpcs_clean(ndev);
+
 	if (priv->hw->pcs != STMMAC_PCS_TBI &&
 	    priv->hw->pcs != STMMAC_PCS_RTBI)
 		stmmac_mdio_unregister(ndev);
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c
index e6133510e28d..101fa50c3c96 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c
@@ -522,6 +522,17 @@ int stmmac_xpcs_setup(struct net_device *ndev)
 	return 0;
 }
 
+void stmmac_xpcs_clean(struct net_device *ndev)
+{
+	struct stmmac_priv *priv = netdev_priv(ndev);
+
+	if (!priv->hw->xpcs)
+		return;
+
+	xpcs_destroy(priv->hw->xpcs);
+	priv->hw->xpcs = NULL;
+}
+
 /**
  * stmmac_mdio_register
  * @ndev: net device structure
@@ -674,9 +685,6 @@ int stmmac_mdio_unregister(struct net_device *ndev)
 	if (!priv->mii)
 		return 0;
 
-	if (priv->hw->xpcs)
-		xpcs_destroy(priv->hw->xpcs);
-
 	mdiobus_unregister(priv->mii);
 	priv->mii->priv = NULL;
 	mdiobus_free(priv->mii);
-- 
2.42.1