net: dsa: mt7530: call port 6 setup from mt7530_mac_config()

mt7530_pad_clk_setup() is called if port 6 is enabled. It used to do more
things than setting up port 6. That part was moved to more appropriate
locations, mt7530_setup() and mt7530_pll_setup().

Now that all it does is set up port 6, rename it to mt7530_setup_port6(),
and move it to a more appropriate location, under mt7530_mac_config().

Change mt7530_setup_port6() to void as there're no error cases.

Leave an empty mt7530_pad_clk_setup() to satisfy the pad_setup function
pointer.

This is the code path for setting up the ports before:

dsa_switch_ops :: phylink_mac_config() -> mt753x_phylink_mac_config()
-> mt753x_mac_config()
   -> mt753x_info :: mac_port_config() -> mt7530_mac_config()
      -> mt7530_setup_port5()
-> mt753x_pad_setup()
   -> mt753x_info :: pad_setup() -> mt7530_pad_clk_setup()

This is after:

dsa_switch_ops :: phylink_mac_config() -> mt753x_phylink_mac_config()
-> mt753x_mac_config()
   -> mt753x_info :: mac_port_config() -> mt7530_mac_config()
      -> mt7530_setup_port5()
      -> mt7530_setup_port6()
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Arınç ÜNAL <arinc.unal@arinc9.com>
Link: https://lore.kernel.org/r/20240206-for-netnext-mt7530-improvements-2-v5-4-d7d92a185cb1@arinc9.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/dsa/mt7530.c

@@ -414,8 +414,8 @@ mt753x_preferred_default_local_cpu_port(struct dsa_switch *ds)
 }
 
 /* Setup port 6 interface mode and TRGMII TX circuit */
-static int
-mt7530_pad_clk_setup(struct dsa_switch *ds, phy_interface_t interface)
+static void
+mt7530_setup_port6(struct dsa_switch *ds, phy_interface_t interface)
 {
 	struct mt7530_priv *priv = ds->priv;
 	u32 ncpo1, ssc_delta, xtal;
@@ -426,7 +426,7 @@ mt7530_pad_clk_setup(struct dsa_switch *ds, phy_interface_t interface)
 	if (interface == PHY_INTERFACE_MODE_RGMII) {
 		mt7530_rmw(priv, MT7530_P6ECR, P6_INTF_MODE_MASK,
 			   P6_INTF_MODE(0));
-		return 0;
+		return;
 	}
 
 	mt7530_rmw(priv, MT7530_P6ECR, P6_INTF_MODE_MASK, P6_INTF_MODE(1));
@@ -465,7 +465,11 @@ mt7530_pad_clk_setup(struct dsa_switch *ds, phy_interface_t interface)
 
 	/* Enable the MT7530 TRGMII clocks */
 	core_set(priv, CORE_TRGMII_GSW_CLK_CG, REG_TRGMIICK_EN);
+}
 
+static int
+mt7530_pad_clk_setup(struct dsa_switch *ds, phy_interface_t interface)
+{
 	return 0;
 }
 
@@ -2613,11 +2617,10 @@ mt7530_mac_config(struct dsa_switch *ds, int port, unsigned int mode,
 {
 	struct mt7530_priv *priv = ds->priv;
 
-	/* Only need to setup port5. */
-	if (port != 5)
-		return 0;
-
-	mt7530_setup_port5(priv->ds, interface);
+	if (port == 5)
+		mt7530_setup_port5(priv->ds, interface);
+	else if (port == 6)
+		mt7530_setup_port6(priv->ds, interface);
 
 	return 0;
 }