[PATCH net-next 3/6] net: stmmac: add get_interfaces() platform method

["Russell King (Oracle)" <rmk+kernel@armlinux.org.uk>]

Add a get_interfaces() platform method to allow platforms to indicate
to phylink which interface modes they support - which then allows
phylink to validate on initialisation that the configured PHY interface
mode is actually supported.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
---
 .../net/ethernet/stmicro/stmmac/stmmac_main.c    | 16 +++++++++++++---
 include/linux/stmmac.h                           |  2 ++
 2 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index ac6ab121eb33..5f66f816a249 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -1283,10 +1283,20 @@ static int stmmac_phy_setup(struct stmmac_priv *priv)
 	if (mdio_bus_data)
 		config->default_an_inband = mdio_bus_data->default_an_inband;
 
-	/* Set the platform/firmware specified interface mode. Note, phylink
-	 * deals with the PHY interface mode, not the MAC interface mode.
+	/* Get the PHY interface modes (at the PHY end of the link) that
+	 * are supported by the platform.
 	 */
-	__set_bit(priv->plat->phy_interface, config->supported_interfaces);
+	if (priv->plat->get_interfaces)
+		priv->plat->get_interfaces(priv, priv->plat->bsp_priv,
+					   config->supported_interfaces);
+
+	/* Set the platform/firmware specified interface mode if the
+	 * supported interfaces have not already been provided using
+	 * phy_interface as a last resort.
+	 */
+	if (phy_interface_empty(config->supported_interfaces))
+		__set_bit(priv->plat->phy_interface,
+			  config->supported_interfaces);
 
 	/* If we have an xpcs, it defines which PHY interfaces are supported. */
 	if (priv->hw->xpcs)
diff --git a/include/linux/stmmac.h b/include/linux/stmmac.h
index 8aed09d65b4a..537bced69c46 100644
--- a/include/linux/stmmac.h
+++ b/include/linux/stmmac.h
@@ -233,6 +233,8 @@ struct plat_stmmacenet_data {
 	u8 tx_sched_algorithm;
 	struct stmmac_rxq_cfg rx_queues_cfg[MTL_MAX_RX_QUEUES];
 	struct stmmac_txq_cfg tx_queues_cfg[MTL_MAX_TX_QUEUES];
+	void (*get_interfaces)(struct stmmac_priv *priv, void *bsp_priv,
+			       unsigned long *interfaces);
 	int (*set_clk_tx_rate)(void *priv, struct clk *clk_tx_i,
 			       phy_interface_t interface, int speed);
 	void (*fix_mac_speed)(void *priv, int speed, unsigned int mode);
-- 
2.30.2