diff mbox series

[RFC,net-next] net: dsa: mt7530: support OF-based registration of switch MDIO bus

Message ID 20240113093216.42391-1-arinc.unal@arinc9.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series [RFC,net-next] net: dsa: mt7530: support OF-based registration of switch MDIO bus | expand

Checks

Context Check Description
netdev/series_format success Single patches do not need cover letters
netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 1092 this patch: 1092
netdev/cc_maintainers success CCed 0 of 0 maintainers
netdev/build_clang success Errors and warnings before: 1107 this patch: 1107
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 1107 this patch: 1107
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 66 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Arınç ÜNAL Jan. 13, 2024, 9:32 a.m. UTC
Currently the MDIO bus of the switches the MT7530 DSA subdriver controls
can only be registered as non-OF-based. Bring support for registering the
bus OF-based.

The subdrivers that control switches [with MDIO bus] probed on OF must
follow this logic to support all cases properly:

No switch MDIO bus defined: Populate ds->user_mii_bus, register the MDIO
bus, set the interrupts for PHYs if "interrupt-controller" is defined at
the switch node. This case should only be covered for the switches which
their dt-bindings documentation didn't document the MDIO bus from the
start. This is to keep supporting the device trees that do not describe the
MDIO bus on the device tree but the MDIO bus is being used nonetheless.

Switch MDIO bus defined: Don't populate ds->user_mii_bus, register the MDIO
bus, set the interrupts for PHYs if ["interrupt-controller" is defined at
the switch node and "interrupts" is defined at the PHY nodes under the
switch MDIO bus node].

Switch MDIO bus defined but explicitly disabled: If the device tree says
status = "disabled" for the MDIO bus, we shouldn't need an MDIO bus at all.
Instead, just exit as early as possible and do not call any MDIO API.

The use of ds->user_mii_bus is inappropriate when the MDIO bus of the
switch is described on the device tree [1], which is why we don't populate
ds->user_mii_bus in that case.

Link: https://lore.kernel.org/netdev/20231213120656.x46fyad6ls7sqyzv@skbuf/ [1]
Suggested-by: David Bauer <mail@david-bauer.net>
Signed-off-by: Arınç ÜNAL <arinc.unal@arinc9.com>
---
 drivers/net/dsa/mt7530.c | 34 ++++++++++++++++++++++++++--------
 1 file changed, 26 insertions(+), 8 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/dsa/mt7530.c b/drivers/net/dsa/mt7530.c
index 391c4dbdff42..cf2ff7680c15 100644
--- a/drivers/net/dsa/mt7530.c
+++ b/drivers/net/dsa/mt7530.c
@@ -2146,24 +2146,40 @@  mt7530_free_irq_common(struct mt7530_priv *priv)
 static void
 mt7530_free_irq(struct mt7530_priv *priv)
 {
-	mt7530_free_mdio_irq(priv);
+	struct device_node *mnp, *np = priv->dev->of_node;
+
+	mnp = of_get_child_by_name(np, "mdio");
+	if (!mnp)
+		mt7530_free_mdio_irq(priv);
+	of_node_put(mnp);
+
 	mt7530_free_irq_common(priv);
 }
 
 static int
 mt7530_setup_mdio(struct mt7530_priv *priv)
 {
+	struct device_node *mnp, *np = priv->dev->of_node;
 	struct dsa_switch *ds = priv->ds;
 	struct device *dev = priv->dev;
 	struct mii_bus *bus;
 	static int idx;
-	int ret;
+	int ret = 0;
+
+	mnp = of_get_child_by_name(np, "mdio");
+
+	if (mnp && !of_device_is_available(mnp))
+		goto out;
 
 	bus = devm_mdiobus_alloc(dev);
-	if (!bus)
-		return -ENOMEM;
+	if (!bus) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	if (!mnp)
+		ds->user_mii_bus = bus;
 
-	ds->user_mii_bus = bus;
 	bus->priv = priv;
 	bus->name = KBUILD_MODNAME "-mii";
 	snprintf(bus->id, MII_BUS_ID_SIZE, KBUILD_MODNAME "-%d", idx++);
@@ -2174,16 +2190,18 @@  mt7530_setup_mdio(struct mt7530_priv *priv)
 	bus->parent = dev;
 	bus->phy_mask = ~ds->phys_mii_mask;
 
-	if (priv->irq)
+	if (priv->irq && !mnp)
 		mt7530_setup_mdio_irq(priv);
 
-	ret = devm_mdiobus_register(dev, bus);
+	ret = devm_of_mdiobus_register(dev, bus, mnp);
 	if (ret) {
 		dev_err(dev, "failed to register MDIO bus: %d\n", ret);
-		if (priv->irq)
+		if (priv->irq && !mnp)
 			mt7530_free_mdio_irq(priv);
 	}
 
+out:
+	of_node_put(mnp);
 	return ret;
 }