net: phy: adin1100: Add SQI support

Determine the SQI from MSE using a predefined table
for the 10BASE-T1L.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Alexandru Tachici <alexandru.tachici@analog.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/phy/adin1100.c

@@ -33,6 +33,26 @@
 #define   ADIN_CRSM_SFT_PD_RDY			BIT(1)
 #define   ADIN_CRSM_SYS_RDY			BIT(0)
 
+#define ADIN_MSE_VAL				0x830B
+
+#define ADIN_SQI_MAX	7
+
+struct adin_mse_sqi_range {
+	u16 start;
+	u16 end;
+};
+
+static const struct adin_mse_sqi_range adin_mse_sqi_map[] = {
+	{ 0x0A74, 0xFFFF },
+	{ 0x084E, 0x0A74 },
+	{ 0x0698, 0x084E },
+	{ 0x053D, 0x0698 },
+	{ 0x0429, 0x053D },
+	{ 0x034E, 0x0429 },
+	{ 0x02A0, 0x034E },
+	{ 0x0000, 0x02A0 },
+};
+
 /**
  * struct adin_priv - ADIN PHY driver private data
  * @tx_level_2v4_able:		set if the PHY supports 2.4V TX levels (10BASE-T1L)
@@ -199,6 +219,36 @@ static int adin_get_features(struct phy_device *phydev)
 	return genphy_c45_pma_read_abilities(phydev);
 }
 
+static int adin_get_sqi(struct phy_device *phydev)
+{
+	u16 mse_val;
+	int sqi;
+	int ret;
+
+	ret = phy_read_mmd(phydev, MDIO_MMD_PMAPMD, MDIO_STAT1);
+	if (ret < 0)
+		return ret;
+	else if (!(ret & MDIO_STAT1_LSTATUS))
+		return 0;
+
+	ret = phy_read_mmd(phydev, MDIO_STAT1, ADIN_MSE_VAL);
+	if (ret < 0)
+		return ret;
+
+	mse_val = 0xFFFF & ret;
+	for (sqi = 0; sqi < ARRAY_SIZE(adin_mse_sqi_map); sqi++) {
+		if (mse_val >= adin_mse_sqi_map[sqi].start && mse_val <= adin_mse_sqi_map[sqi].end)
+			return sqi;
+	}
+
+	return -EINVAL;
+}
+
+static int adin_get_sqi_max(struct phy_device *phydev)
+{
+	return ADIN_SQI_MAX;
+}
+
 static int adin_probe(struct phy_device *phydev)
 {
 	struct device *dev = &phydev->mdio.dev;
@@ -225,6 +275,8 @@ static struct phy_driver adin_driver[] = {
 		.set_loopback		= adin_set_loopback,
 		.suspend		= adin_suspend,
 		.resume			= adin_resume,
+		.get_sqi		= adin_get_sqi,
+		.get_sqi_max		= adin_get_sqi_max,
 	},
 };