net: stmmac: Support a generic PCS field in mac_device_info

Global stmmac support for early initialization of PCS devices requires a
generic PCS reference that can be passed to phylink_pcs_pre_init().
Currently, the mac_device_info struct contains only one PCS field, which is
specific to the Lynx model.

As PCS models are hardware-specific, it is more appropriate to have a
generic PCS field in the mac_device_info struct.

Refactor the lynx_pcs field into a generic phylink_pcs field.
Signed-off-by: Romain Gantois <romain.gantois@bootlin.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20240326-rxc_bugfix-v6-4-24a74e5c761f@bootlin.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/stmicro/stmmac/common.h

@@ -593,7 +593,7 @@ struct mac_device_info {
 	const struct stmmac_mmc_ops *mmc;
 	const struct stmmac_est_ops *est;
 	struct dw_xpcs *xpcs;
-	struct phylink_pcs *lynx_pcs; /* Lynx external PCS */
+	struct phylink_pcs *phylink_pcs;
 	struct mii_regs mii;	/* MII register Addresses */
 	struct mac_link link;
 	void __iomem *pcsr;     /* vpointer to device CSRs */

drivers/net/ethernet/stmicro/stmmac/dwmac-socfpga.c

@@ -479,9 +479,9 @@ static int socfpga_dwmac_probe(struct platform_device *pdev)
 			goto err_dvr_remove;
 		}
 
-		stpriv->hw->lynx_pcs = lynx_pcs_create_mdiodev(pcs_bus, 0);
-		if (IS_ERR(stpriv->hw->lynx_pcs)) {
-			ret = PTR_ERR(stpriv->hw->lynx_pcs);
+		stpriv->hw->phylink_pcs = lynx_pcs_create_mdiodev(pcs_bus, 0);
+		if (IS_ERR(stpriv->hw->phylink_pcs)) {
+			ret = PTR_ERR(stpriv->hw->phylink_pcs);
 			goto err_dvr_remove;
 		}
 	}
@@ -498,7 +498,7 @@ static void socfpga_dwmac_remove(struct platform_device *pdev)
 {
 	struct net_device *ndev = platform_get_drvdata(pdev);
 	struct stmmac_priv *priv = netdev_priv(ndev);
-	struct phylink_pcs *pcs = priv->hw->lynx_pcs;
+	struct phylink_pcs *pcs = priv->hw->phylink_pcs;
 
 	stmmac_pltfr_remove(pdev);
 

drivers/net/ethernet/stmicro/stmmac/stmmac_main.c

@@ -944,10 +944,7 @@ static struct phylink_pcs *stmmac_mac_select_pcs(struct phylink_config *config,
 	if (priv->hw->xpcs)
 		return &priv->hw->xpcs->pcs;
 
-	if (priv->hw->lynx_pcs)
-		return priv->hw->lynx_pcs;
-
-	return NULL;
+	return priv->hw->phylink_pcs;
 }
 
 static void stmmac_mac_config(struct phylink_config *config, unsigned int mode,