net: freescale: ucc_geth: Introduce a helper to check Reduced modes

A number of parallel MII interfaces also exist in a "Reduced" mode,
usually with higher clock rates and fewer data lines, to ease the
hardware design. This is what the 'R' stands for in RGMII, RMII, RTBI,
RXAUI, etc.

The UCC Geth controller has a special configuration bit that needs to be
set when the MII mode is one of the supported reduced modes.

Add a local helper for that.

Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/freescale/ucc_geth.c

@@ -1258,6 +1258,13 @@ static int init_min_frame_len(u16 min_frame_length,
 	return 0;
 }
 
+static bool phy_interface_mode_is_reduced(phy_interface_t interface)
+{
+	return phy_interface_mode_is_rgmii(interface) ||
+	       interface == PHY_INTERFACE_MODE_RMII ||
+	       interface == PHY_INTERFACE_MODE_RTBI;
+}
+
 static int adjust_enet_interface(struct ucc_geth_private *ugeth)
 {
 	struct ucc_geth_info *ug_info;
@@ -1290,12 +1297,7 @@ static int adjust_enet_interface(struct ucc_geth_private *ugeth)
 	upsmr = in_be32(&uf_regs->upsmr);
 	upsmr &= ~(UCC_GETH_UPSMR_RPM | UCC_GETH_UPSMR_R10M |
 		   UCC_GETH_UPSMR_TBIM | UCC_GETH_UPSMR_RMM);
-	if ((ugeth->phy_interface == PHY_INTERFACE_MODE_RMII) ||
-	    (ugeth->phy_interface == PHY_INTERFACE_MODE_RGMII) ||
-	    (ugeth->phy_interface == PHY_INTERFACE_MODE_RGMII_ID) ||
-	    (ugeth->phy_interface == PHY_INTERFACE_MODE_RGMII_RXID) ||
-	    (ugeth->phy_interface == PHY_INTERFACE_MODE_RGMII_TXID) ||
-	    (ugeth->phy_interface == PHY_INTERFACE_MODE_RTBI)) {
+	if (phy_interface_mode_is_reduced(ugeth->phy_interface)) {
 		if (ugeth->phy_interface != PHY_INTERFACE_MODE_RMII)
 			upsmr |= UCC_GETH_UPSMR_RPM;
 		switch (ugeth->max_speed) {
@@ -1594,9 +1596,7 @@ static void ugeth_link_up(struct ucc_geth_private *ugeth,
 				    ~(MACCFG2_INTERFACE_MODE_MASK)) |
 				    MACCFG2_INTERFACE_MODE_NIBBLE);
 			/* if reduced mode, re-set UPSMR.R10M */
-			if (interface == PHY_INTERFACE_MODE_RMII ||
-			    phy_interface_mode_is_rgmii(interface) ||
-			    interface == PHY_INTERFACE_MODE_RTBI) {
+			if (phy_interface_mode_is_reduced(interface)) {
 				if (speed == SPEED_10)
 					upsmr |= UCC_GETH_UPSMR_R10M;
 				else