phy: rockchip: naneng-combphy: Add ssc enable option from firmware

Change-Id: I0f620b6ff000ff4e7b9bc997ca2c30c14d3f8cde
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>

drivers/phy/rockchip/phy-rockchip-naneng-combphy.c

@@ -537,6 +537,12 @@ static int rk3568_combphy_cfg(struct rockchip_combphy_priv *priv)
 		}
 	}
 
+	if (device_property_read_bool(priv->dev, "rockchip,enable-ssc")) {
+		val = readl(priv->mmio + (0x7 << 2));
+		val |= BIT(4);
+		writel(val, priv->mmio + (0x7 << 2));
+	}
+
 	return 0;
 }