Subject: [PATCH v2 2/2] net: phy: realtek: Change TX-delay setting for RGMII modes only

From: Serge Semin <[email-masked]>
Date: Sat, 27 Apr 2019 00:21:12 +0300

It's prone to problems if delay is cleared out for other than RGMII
modes. So lets set/clear the TX-delay in the config register only
if actually RGMII-like interface mode is requested.

Signed-off-by: Serge Semin <[email-masked]>

---
 drivers/net/phy/realtek.c | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/drivers/net/phy/realtek.c b/drivers/net/phy/realtek.c
index ab567a1923ad..a18cb01158f9 100644
--- a/drivers/net/phy/realtek.c
+++ b/drivers/net/phy/realtek.c
@@ -163,16 +163,24 @@ static int rtl8211c_config_init(struct phy_device *phydev)
 static int rtl8211f_config_init(struct phy_device *phydev)
 {
 	int ret;
-	u16 val = 0;
+	u16 val;
 
 	ret = genphy_config_init(phydev);
 	if (ret < 0)
 		return ret;
 
-	/* enable TX-delay for rgmii-id and rgmii-txid, otherwise disable it */
-	if (phydev->interface == PHY_INTERFACE_MODE_RGMII_ID ||
-	    phydev->interface == PHY_INTERFACE_MODE_RGMII_TXID)
+	/* enable TX-delay for rgmii-id/rgmii-txid, and disable it for rgmii */
+	switch (phydev->interface) {
+	case PHY_INTERFACE_MODE_RGMII:
+		val = 0;
+		break;
+	case PHY_INTERFACE_MODE_RGMII_ID:
+	case PHY_INTERFACE_MODE_RGMII_TXID:
 		val = RTL8211F_TX_DELAY;
+		break;
+	default: /* the rest of the modes imply leaving delay as is. */
+		return 0;
+	}
 
 	return phy_modify_paged(phydev, 0xd08, 0x11, RTL8211F_TX_DELAY, val);
 }
-- 
2.21.0