[RFC PATCH net-next v4 25/28] net: dsa: qca8k: add support for internal phy

[Ansuel Smith]

Add support to setup_mdio_bus for internal phy declaration. Introduce a
flag to use the legacy port phy mapping by default and use the direct
mapping if a mdio node is detected in the switch node.

Signed-off-by: Ansuel Smith <ansuelsmth@xxxxxxxxx>
---
 drivers/net/dsa/qca8k.c | 46 +++++++++++++++++++++++++++--------------
 drivers/net/dsa/qca8k.h |  1 +
 2 files changed, 32 insertions(+), 15 deletions(-)

diff --git a/drivers/net/dsa/qca8k.c b/drivers/net/dsa/qca8k.c
index f96579c0bd46..3d195fdd7ed5 100644
--- a/drivers/net/dsa/qca8k.c
+++ b/drivers/net/dsa/qca8k.c
@@ -663,19 +663,15 @@ qca8k_mdio_busy_wait(struct qca8k_priv *priv, u32 reg, u32 mask)
 }
 
 static int
-qca8k_mdio_write(struct qca8k_priv *priv, int port, u32 regnum, u16 data)
+qca8k_mdio_write(struct qca8k_priv *priv, int phy, u32 regnum, u16 data)
 {
 	u16 r1, r2, page;
-	u32 phy, val;
+	u32 val;
 	int ret;
 
 	if (regnum >= QCA8K_MDIO_MASTER_MAX_REG)
 		return -EINVAL;
 
-	/* callee is responsible for not passing bad ports,
-	 * but we still would like to make spills impossible.
-	 */
-	phy = qca8k_port_to_phy(port) % PHY_MAX_ADDR;
 	val = QCA8K_MDIO_MASTER_BUSY | QCA8K_MDIO_MASTER_EN |
 	      QCA8K_MDIO_MASTER_WRITE | QCA8K_MDIO_MASTER_PHY_ADDR(phy) |
 	      QCA8K_MDIO_MASTER_REG_ADDR(regnum) |
@@ -705,19 +701,15 @@ qca8k_mdio_write(struct qca8k_priv *priv, int port, u32 regnum, u16 data)
 }
 
 static int
-qca8k_mdio_read(struct qca8k_priv *priv, int port, u32 regnum)
+qca8k_mdio_read(struct qca8k_priv *priv, int phy, u32 regnum)
 {
 	u16 r1, r2, page;
-	u32 phy, val;
+	u32 val;
 	int ret;
 
 	if (regnum >= QCA8K_MDIO_MASTER_MAX_REG)
 		return -EINVAL;
 
-	/* callee is responsible for not passing bad ports,
-	 * but we still would like to make spills impossible.
-	 */
-	phy = qca8k_port_to_phy(port) % PHY_MAX_ADDR;
 	val = QCA8K_MDIO_MASTER_BUSY | QCA8K_MDIO_MASTER_EN |
 	      QCA8K_MDIO_MASTER_READ | QCA8K_MDIO_MASTER_PHY_ADDR(phy) |
 	      QCA8K_MDIO_MASTER_REG_ADDR(regnum);
@@ -758,6 +750,13 @@ qca8k_phy_write(struct dsa_switch *ds, int port, int regnum, u16 data)
 {
 	struct qca8k_priv *priv = ds->priv;
 
+	/* Check if the legacy mapping should be used and the
+	 * port is not correctly mapped to the right PHY in the
+	 * devicetree
+	 */
+	if (priv->legacy_phy_port_mapping)
+		port = qca8k_port_to_phy(port) % PHY_MAX_ADDR;
+
 	return qca8k_mdio_write(priv, port, regnum, data);
 }
 
@@ -767,6 +766,13 @@ qca8k_phy_read(struct dsa_switch *ds, int port, int regnum)
 	struct qca8k_priv *priv = ds->priv;
 	int ret;
 
+	/* Check if the legacy mapping should be used and the
+	 * port is not correctly mapped to the right PHY in the
+	 * devicetree
+	 */
+	if (priv->legacy_phy_port_mapping)
+		port = qca8k_port_to_phy(port) % PHY_MAX_ADDR;
+
 	ret = qca8k_mdio_read(priv, port, regnum);
 
 	if (ret < 0)
@@ -779,7 +785,7 @@ static int
 qca8k_setup_mdio_bus(struct qca8k_priv *priv)
 {
 	u32 internal_mdio_mask = 0, external_mdio_mask = 0, reg;
-	struct device_node *ports, *port;
+	struct device_node *ports, *port, *mdio;
 	int err;
 
 	ports = of_get_child_by_name(priv->dev->of_node, "ports");
@@ -800,7 +806,8 @@ qca8k_setup_mdio_bus(struct qca8k_priv *priv)
 		if (!dsa_is_user_port(priv->ds, reg))
 			continue;
 
-		if (of_property_read_bool(port, "phy-handle"))
+		if (of_property_read_bool(port, "phy-handle") &&
+		    of_property_match_string(port, "phy-mode", "internal") < 0)
 			external_mdio_mask |= BIT(reg);
 		else
 			internal_mdio_mask |= BIT(reg);
@@ -837,6 +844,14 @@ qca8k_setup_mdio_bus(struct qca8k_priv *priv)
 				       QCA8K_MDIO_MASTER_EN);
 	}
 
+	/* Check if the devicetree declare the port:phy mapping
+	 * If a mapping can't be found the legacy mapping is used,
+	 * using the qca8k_port_to_phy function
+	 */
+	mdio = of_get_child_by_name(priv->dev->of_node, "mdio");
+	if (!mdio)
+		priv->legacy_phy_port_mapping = true;
+
 	priv->ops.phy_read = qca8k_phy_read;
 	priv->ops.phy_write = qca8k_phy_write;
 	return 0;
@@ -1198,7 +1213,8 @@ qca8k_phylink_validate(struct dsa_switch *ds, int port,
 	case 5:
 		/* Internal PHY */
 		if (state->interface != PHY_INTERFACE_MODE_NA &&
-		    state->interface != PHY_INTERFACE_MODE_GMII)
+		    state->interface != PHY_INTERFACE_MODE_GMII &&
+		    state->interface != PHY_INTERFACE_MODE_INTERNAL)
 			goto unsupported;
 		break;
 	case 6: /* 2nd CPU port / external PHY */
diff --git a/drivers/net/dsa/qca8k.h b/drivers/net/dsa/qca8k.h
index d365f85ab34f..ed3b05ad6745 100644
--- a/drivers/net/dsa/qca8k.h
+++ b/drivers/net/dsa/qca8k.h
@@ -255,6 +255,7 @@ struct qca8k_priv {
 	u8 switch_revision;
 	u8 rgmii_tx_delay;
 	u8 rgmii_rx_delay;
+	bool legacy_phy_port_mapping;
 	struct regmap *regmap;
 	struct mii_bus *bus;
 	struct ar8xxx_port_status port_sts[QCA8K_NUM_PORTS];
-- 
2.30.2