net: dsa: microchip: implement lan937x-specific MDIO registration

All the switches use a common mdio_register() function that uses two
ksz_dev_ops callbacks (.mdio_bus_preinit() and .create_phy_addr_map())
to handle the lan937x specific case. These two callbacks are used only
at this place in the code.

Implement a new lan937x-specific MDIO registration functions that uses
these two lan937x-specific functions. The lan937x bindings don't
have any 'interrupts' property so this lan937x_mdio_register() doesn't
call ksz_irq_phy_setup().
Expose the common ksz_*_mdio_{read/write} functions so they can be used
in lan937x.c
Remove the callbacks from ksz_dev_ops.

Signed-off-by: Bastien Curutchet (Schneider Electric) <bastien.curutchet@bootlin.com>
Link: https://patch.msgid.link/20260608-clean-ksz-3rd-v2-9-6e61b7be23c4@bootlin.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c
index 7dc8e4ffacddaeb2c93d4837f7a656ae26273439..d08659ffa4427adc23069be86632a5090ffe68ee 100644 (file)
--- a/drivers/net/dsa/microchip/ksz_common.c
+++ b/drivers/net/dsa/microchip/ksz_common.c
@@ -2256,7 +2256,7 @@ static void ksz_update_port_member(struct ksz_device *dev, int port)
        dev->dev_ops->cfg_port_member(dev, port, port_member | cpu_port);
 }
 
-static int ksz_sw_mdio_read(struct mii_bus *bus, int addr, int regnum)
+int ksz_sw_mdio_read(struct mii_bus *bus, int addr, int regnum)
 {
        struct ksz_device *dev = bus->priv;
        struct dsa_switch *ds = dev->ds;
@@ -2264,8 +2264,7 @@ static int ksz_sw_mdio_read(struct mii_bus *bus, int addr, int regnum)
        return ds->ops->phy_read(ds, addr, regnum);
 }
 
-static int ksz_sw_mdio_write(struct mii_bus *bus, int addr, int regnum,
-                            u16 val)
+int ksz_sw_mdio_write(struct mii_bus *bus, int addr, int regnum, u16 val)
 {
        struct ksz_device *dev = bus->priv;
        struct dsa_switch *ds = dev->ds;
@@ -2286,7 +2285,7 @@ static int ksz_sw_mdio_write(struct mii_bus *bus, int addr, int regnum,
  *
  * Return: Value of the PHY register, or a negative error code on failure.
  */
-static int ksz_parent_mdio_read(struct mii_bus *bus, int addr, int regnum)
+int ksz_parent_mdio_read(struct mii_bus *bus, int addr, int regnum)
 {
        struct ksz_device *dev = bus->priv;
 
@@ -2306,8 +2305,7 @@ static int ksz_parent_mdio_read(struct mii_bus *bus, int addr, int regnum)
  *
  * Return: 0 on success, or a negative error code on failure.
  */
-static int ksz_parent_mdio_write(struct mii_bus *bus, int addr, int regnum,
-                                u16 val)
+int ksz_parent_mdio_write(struct mii_bus *bus, int addr, int regnum, u16 val)
 {
        struct ksz_device *dev = bus->priv;
 
@@ -2415,8 +2413,8 @@ static void ksz_irq_phy_free(struct ksz_device *dev)
  *
  * Return: 0 on success, or a negative error code on failure.
  */
-static int ksz_parse_dt_phy_config(struct ksz_device *dev, struct mii_bus *bus,
-                                  struct device_node *mdio_np)
+int ksz_parse_dt_phy_config(struct ksz_device *dev, struct mii_bus *bus,
+                           struct device_node *mdio_np)
 {
        struct device_node *phy_node, *phy_parent_node;
        bool phys_are_valid = true;
@@ -2519,20 +2517,8 @@ int ksz_mdio_register(struct ksz_device *dev)
                goto put_mdio_node;
        }
 
-       if (dev->dev_ops->mdio_bus_preinit) {
-               ret = dev->dev_ops->mdio_bus_preinit(dev, !!parent_bus);
-               if (ret)
-                       goto put_mdio_node;
-       }
-
-       if (dev->dev_ops->create_phy_addr_map) {
-               ret = dev->dev_ops->create_phy_addr_map(dev, !!parent_bus);
-               if (ret)
-                       goto put_mdio_node;
-       } else {
-               for (i = 0; i < dev->info->port_cnt; i++)
-                       dev->phy_addr_map[i] = i;
-       }
+       for (i = 0; i < dev->info->port_cnt; i++)
+               dev->phy_addr_map[i] = i;
 
        bus->priv = dev;
        if (parent_bus) {

diff --git a/drivers/net/dsa/microchip/ksz_common.h b/drivers/net/dsa/microchip/ksz_common.h
index bdc93f2855c71c9c5a44e039ac40ddb77943da5a..0c10cd5775bc314b4a6f7767ec6a992b76a0617e 100644 (file)
--- a/drivers/net/dsa/microchip/ksz_common.h
+++ b/drivers/net/dsa/microchip/ksz_common.h
@@ -366,42 +366,6 @@ struct ksz_dev_ops {
        u32 (*get_port_addr)(int port, int offset);
        void (*cfg_port_member)(struct ksz_device *dev, int port, u8 member);
 
-       /**
-        * @mdio_bus_preinit: Function pointer to pre-initialize the MDIO bus
-        *                    for accessing PHYs.
-        * @dev: Pointer to device structure.
-        * @side_mdio: Boolean indicating if the PHYs are accessed over a side
-        *             MDIO bus.
-        *
-        * This function pointer is used to configure the MDIO bus for PHY
-        * access before initiating regular PHY operations. It enables either
-        * SPI/I2C or side MDIO access modes by unlocking necessary registers
-        * and setting up access permissions for the selected mode.
-        *
-        * Return:
-        *  - 0 on success.
-        *  - Negative error code on failure.
-        */
-       int (*mdio_bus_preinit)(struct ksz_device *dev, bool side_mdio);
-
-       /**
-        * @create_phy_addr_map: Function pointer to create a port-to-PHY
-        *                       address map.
-        * @dev: Pointer to device structure.
-        * @side_mdio: Boolean indicating if the PHYs are accessed over a side
-        *             MDIO bus.
-        *
-        * This function pointer is responsible for mapping switch ports to PHY
-        * addresses according to the configured access mode (SPI or side MDIO)
-        * and the device’s strap configuration. The mapping setup may vary
-        * depending on the chip variant and configuration. Ensures the correct
-        * address mapping for PHY communication.
-        *
-        * Return:
-        *  - 0 on success.
-        *  - Negative error code on failure (e.g., invalid configuration).
-        */
-       int (*create_phy_addr_map)(struct ksz_device *dev, bool side_mdio);
        void (*r_mib_cnt)(struct ksz_device *dev, int port, u16 addr,
                          u64 *cnt);
        void (*r_mib_pkt)(struct ksz_device *dev, int port, u16 addr,
@@ -498,6 +462,12 @@ int ksz_port_set_mac_address(struct dsa_switch *ds, int port,
 int ksz_suspend(struct dsa_switch *ds);
 int ksz_resume(struct dsa_switch *ds);
 
+int ksz_parse_dt_phy_config(struct ksz_device *dev, struct mii_bus *bus,
+                           struct device_node *mdio_np);
+int ksz_sw_mdio_read(struct mii_bus *bus, int addr, int regnum);
+int ksz_sw_mdio_write(struct mii_bus *bus, int addr, int regnum, u16 val);
+int ksz_parent_mdio_read(struct mii_bus *bus, int addr, int regnum);
+int ksz_parent_mdio_write(struct mii_bus *bus, int addr, int regnum, u16 val);
 int ksz_mdio_register(struct ksz_device *dev);
 int ksz_pirq_setup(struct ksz_device *dev, u8 p);
 int ksz_girq_setup(struct ksz_device *dev);

diff --git a/drivers/net/dsa/microchip/lan937x_main.c b/drivers/net/dsa/microchip/lan937x_main.c
index d45798de4ce9d57bf20a972e86f1088c7168302e..48cd367455c3caf5926aebb56bfbec25296b5f9a 100644 (file)
--- a/drivers/net/dsa/microchip/lan937x_main.c
+++ b/drivers/net/dsa/microchip/lan937x_main.c
@@ -7,6 +7,7 @@
 #include <linux/module.h>
 #include <linux/iopoll.h>
 #include <linux/phy.h>
+#include <linux/of_mdio.h>
 #include <linux/of_net.h>
 #include <linux/if_bridge.h>
 #include <linux/if_vlan.h>
@@ -669,6 +670,101 @@ static int lan937x_switch_init(struct ksz_device *dev)
        return 0;
 }
 
+/**
+ * lan937x_mdio_register - Register and configure the MDIO bus for the LAN937x.
+ * @dev: Pointer to the KSZ device structure.
+ *
+ * This function sets up and registers an MDIO bus for a LAN937x switch,
+ * allowing access to its internal PHYs. If the device supports side MDIO,
+ * the function will configure the external MDIO controller specified by the
+ * "mdio-parent-bus" device tree property to directly manage internal PHYs.
+ * Otherwise, SPI or I2C access is set up for PHY access.
+ *
+ * Return: 0 on success, or a negative error code on failure.
+ */
+static int lan937x_mdio_register(struct ksz_device *dev)
+{
+       struct device_node *parent_bus_node;
+       struct mii_bus *parent_bus = NULL;
+       struct dsa_switch *ds = dev->ds;
+       struct device_node *mdio_np;
+       struct mii_bus *bus;
+       int ret;
+
+       mdio_np = of_get_child_by_name(dev->dev->of_node, "mdio");
+       if (!mdio_np)
+               return 0;
+
+       parent_bus_node = of_parse_phandle(mdio_np, "mdio-parent-bus", 0);
+       if (parent_bus_node && !dev->info->phy_side_mdio_supported) {
+               dev_err(dev->dev, "Side MDIO bus is not supported for this HW, ignoring 'mdio-parent-bus' property.\n");
+               ret = -EINVAL;
+
+               goto put_mdio_node;
+       } else if (parent_bus_node) {
+               parent_bus = of_mdio_find_bus(parent_bus_node);
+               if (!parent_bus) {
+                       ret = -EPROBE_DEFER;
+
+                       goto put_mdio_node;
+               }
+
+               dev->parent_mdio_bus = parent_bus;
+       }
+
+       bus = devm_mdiobus_alloc(ds->dev);
+       if (!bus) {
+               ret = -ENOMEM;
+               goto put_mdio_node;
+       }
+
+       ret = lan937x_mdio_bus_preinit(dev, !!parent_bus);
+       if (ret)
+               goto put_mdio_node;
+
+       ret = lan937x_create_phy_addr_map(dev, !!parent_bus);
+       if (ret)
+               goto put_mdio_node;
+
+       bus->priv = dev;
+       if (parent_bus) {
+               bus->read = ksz_parent_mdio_read;
+               bus->write = ksz_parent_mdio_write;
+               bus->name = "KSZ side MDIO";
+               snprintf(bus->id, MII_BUS_ID_SIZE, "ksz-side-mdio-%d",
+                        ds->index);
+       } else {
+               bus->read = ksz_sw_mdio_read;
+               bus->write = ksz_sw_mdio_write;
+               bus->name = "ksz user smi";
+               if (ds->dst->index != 0)
+                       snprintf(bus->id, MII_BUS_ID_SIZE, "SMI-%d-%d",
+                                ds->dst->index, ds->index);
+               else
+                       snprintf(bus->id, MII_BUS_ID_SIZE, "SMI-%d", ds->index);
+       }
+
+       ret = ksz_parse_dt_phy_config(dev, bus, mdio_np);
+       if (ret)
+               goto put_mdio_node;
+
+       ds->phys_mii_mask = bus->phy_mask;
+       bus->parent = ds->dev;
+
+       ds->user_mii_bus = bus;
+
+       ret = devm_of_mdiobus_register(ds->dev, bus, mdio_np);
+       if (ret)
+               dev_err(ds->dev, "unable to register MDIO bus %s\n",
+                       bus->id);
+
+put_mdio_node:
+       of_node_put(mdio_np);
+       of_node_put(parent_bus_node);
+
+       return ret;
+}
+
 static int lan937x_setup(struct dsa_switch *ds)
 {
        struct ksz_device *dev = ds->priv;
@@ -782,7 +878,7 @@ static int lan937x_setup(struct dsa_switch *ds)
                goto port_release;
        }
 
-       ret = ksz_mdio_register(dev);
+       ret = lan937x_mdio_register(dev);
        if (ret < 0) {
                dev_err(dev->dev, "failed to register the mdio");
                goto out_ptp_clock_unregister;
@@ -845,8 +941,6 @@ const struct phylink_mac_ops lan937x_phylink_mac_ops = {
 const struct ksz_dev_ops lan937x_dev_ops = {
        .get_port_addr = ksz9477_get_port_addr,
        .cfg_port_member = ksz9477_cfg_port_member,
-       .mdio_bus_preinit = lan937x_mdio_bus_preinit,
-       .create_phy_addr_map = lan937x_create_phy_addr_map,
        .r_mib_cnt = ksz9477_r_mib_cnt,
        .r_mib_pkt = ksz9477_r_mib_pkt,
        .r_mib_stat64 = ksz_r_mib_stats64,