net: mdio: realtek-rtl9300: reorder controller setup

After the former refactoring the existing otto_emdio_9300_mdiobus_init()
contains only the c22/c45 bus mode setup. Like the topology setup this
must run before bus registration. Otherwise the bus does not "speak" the
right protocol for PHY setup.

This setup is device-specific and other SoCs will need to set up other
register bits in the controller in the future. Therefore

- Relocate c22/c45 device tree readout to the very beginning of the probing
- Add a new device-specific setup_controller() into the info structure.
- Relocate otto_emdio_priv to satisfy the new info structure dependency.
- Rename otto_emdio_9300_mdiobus_init accordingly and add it to the
  RTL9300 info structure. At the same time, adapt register naming
  for the function to make it clear that it only applies to this SoC.
- Call setup_controller() prior to bus registration.

Signed-off-by: Markus Stockhausen <markus.stockhausen@gmx.de>
Link: https://patch.msgid.link/20260603175924.123019-7-markus.stockhausen@gmx.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 24 insertions, 20 deletions

diff --git a/drivers/net/mdio/mdio-realtek-rtl9300.c b/drivers/net/mdio/mdio-realtek-rtl9300.c
index e626dd7fb4b8..bd361aa19739 100644
--- a/drivers/net/mdio/mdio-realtek-rtl9300.c
+++ b/drivers/net/mdio/mdio-realtek-rtl9300.c
@@ -54,8 +54,8 @@
 #define RTL9300_NUM_BUSES			4
 #define RTL9300_NUM_PAGES			4096
 #define RTL9300_NUM_PORTS			28
-#define SMI_GLB_CTRL				0xca00
-#define   GLB_CTRL_INTF_SEL(intf)		BIT(16 + (intf))
+#define RTL9300_SMI_GLB_CTRL			0xca00
+#define   RTL9300_GLB_CTRL_INTF_SEL(intf)	BIT(16 + (intf))
 #define RTL9300_SMI_PORT0_15_POLLING_SEL	0xca08
 #define RTL9300_SMI_ACCESS_PHY_CTRL_0		0xcb70
 #define RTL9300_SMI_ACCESS_PHY_CTRL_1		0xcb74
@@ -92,6 +92,17 @@ struct otto_emdio_cmd_regs {
 	u32 port_mask_low;
 };
 
+struct otto_emdio_priv {
+	const struct otto_emdio_info *info;
+	struct regmap *regmap;
+	struct mutex lock; /* protect HW access */
+	DECLARE_BITMAP(valid_ports, MAX_PORTS);
+	u8 smi_bus[MAX_PORTS];
+	u8 smi_addr[MAX_PORTS];
+	bool smi_bus_is_c45[MAX_SMI_BUSSES];
+	struct mii_bus *bus[MAX_SMI_BUSSES];
+};
+
 struct otto_emdio_info {
 	u32 addr_map_base;
 	u32 bus_map_base;
@@ -102,23 +113,13 @@ struct otto_emdio_info {
 	u8 num_buses;
 	u8 num_ports;
 	u16 num_pages;
+	int (*setup_controller)(struct otto_emdio_priv *priv);
 	int (*read_c22)(struct mii_bus *bus, int port, int regnum, u32 *value);
 	int (*read_c45)(struct mii_bus *bus, int port, int dev_addr, int regnum, u32 *value);
 	int (*write_c22)(struct mii_bus *bus, int port, int regnum, u16 value);
 	int (*write_c45)(struct mii_bus *bus, int port, int dev_addr, int regnum, u16 value);
 };
 
-struct otto_emdio_priv {
-	const struct otto_emdio_info *info;
-	struct regmap *regmap;
-	struct mutex lock; /* protect HW access */
-	DECLARE_BITMAP(valid_ports, MAX_PORTS);
-	u8 smi_bus[MAX_PORTS];
-	u8 smi_addr[MAX_PORTS];
-	bool smi_bus_is_c45[MAX_SMI_BUSSES];
-	struct mii_bus *bus[MAX_SMI_BUSSES];
-};
-
 struct otto_emdio_chan {
 	struct otto_emdio_priv *priv;
 	u8 mdio_bus;
@@ -369,7 +370,7 @@ static int otto_emdio_setup_topology(struct otto_emdio_priv *priv)
 	return 0;
 }
 
-static int otto_emdio_9300_mdiobus_init(struct otto_emdio_priv *priv)
+static int otto_emdio_9300_setup_controller(struct otto_emdio_priv *priv)
 {
 	u32 glb_ctrl_mask = 0, glb_ctrl_val = 0;
 	struct regmap *regmap = priv->regmap;
@@ -379,9 +380,9 @@ static int otto_emdio_9300_mdiobus_init(struct otto_emdio_priv *priv)
 	glb_ctrl_mask = GENMASK(19, 16);
 	for (i = 0; i < priv->info->num_buses; i++)
 		if (priv->smi_bus_is_c45[i])
-			glb_ctrl_val |= GLB_CTRL_INTF_SEL(i);
+			glb_ctrl_val |= RTL9300_GLB_CTRL_INTF_SEL(i);
 
-	err = regmap_update_bits(regmap, SMI_GLB_CTRL,
+	err = regmap_update_bits(regmap, RTL9300_SMI_GLB_CTRL,
 				 glb_ctrl_mask, glb_ctrl_val);
 	if (err)
 		return err;
@@ -548,16 +549,18 @@ static int otto_emdio_probe(struct platform_device *pdev)
 	if (err)
 		return err;
 
+	if (priv->info->setup_controller) {
+		err = priv->info->setup_controller(priv);
+		if (err)
+			return dev_err_probe(dev, err, "failed to setup MDIO bus controller\n");
+	}
+
 	device_for_each_child_node_scoped(dev, child) {
 		err = otto_emdio_probe_one(dev, priv, child);
 		if (err)
 			return err;
 	}
 
-	err = otto_emdio_9300_mdiobus_init(priv);
-	if (err)
-		return dev_err_probe(dev, err, "failed to initialise MDIO bus controller\n");
-
 	return 0;
 }
 
@@ -576,6 +579,7 @@ static const struct otto_emdio_info otto_emdio_9300_info = {
 	.num_buses = RTL9300_NUM_BUSES,
 	.num_ports = RTL9300_NUM_PORTS,
 	.num_pages = RTL9300_NUM_PAGES,
+	.setup_controller = otto_emdio_9300_setup_controller,
 	.read_c22 = otto_emdio_9300_read_c22,
 	.read_c45 = otto_emdio_9300_read_c45,
 	.write_c22 = otto_emdio_9300_write_c22,