ksz_mdio_register(9)

💅 ksz_mdio_register(9) — the kernel API manual, but make it make sense

okay so bestie, welcome to ksz_mdio_register(9), straight out of the Kernel API Manual. this is the one that gets your KSZ device's MDIO bus living its best life ✨

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✨ NAME ✨

ksz_mdio_register — register and configure the MDIO bus for the KSZ device. that's it, that's the whole vibe 🎀

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🌸 SYNOPSIS 🌸

int ksz_mdio_register (struct ksz_device *dev );

yeah, one argument. one. we love a low-effort signature 👑

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🦋 ARGUMENTS 🦋

• dev — pointer to the struct ksz_device structure. this is the KSZ device in question, the main character of the function, hand it over and let it cook 🫶

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💖 DESCRIPTION 💖

so what does this actually do? it sets up and registers an MDIO bus for the KSZ switch device, which is the whole point — that bus is how you get access to the device's internal PHYs. no bus, no PHY access, no slay. 😭

here's the tea though: the behaviour forks depending on your hardware. if the device supports side MDIO, the function configures the external MDIO controller — the one specified by the "mdio-parent-bus" device tree property — so it directly manages the internal PHYs. iconic delegation, honestly. 💅

otherwise? if side MDIO isn't a thing for your device, it sets up SPI or I2C access for PHY access instead. different route, same destination. lowkey flexible of it 🌈

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🔥 RETURN 🔥

• 0 on success 🎉
• a negative error code on failure 💀 (yes it's negative, no we're not elaborating, that's the deal)

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👑 SEE ALSO 👑

the kernel file, in case you wanna go read the source like the academic weapon you are:

./drivers/net/dsa/microchip/ksz_common.c

and the whole friend group of related calls, fr fr:

• ksz_phylink_mac_disable_tx_lpi(9)
• ksz_phylink_mac_enable_tx_lpi(9)
• ksz_update_port_member(9)
• ksz_parent_mdio_read(9)
• ksz_parent_mdio_write(9)
• ksz_phy_addr_to_port(9)
• ksz_irq_phy_setup(9)
• ksz_irq_phy_free(9)
• ksz_parse_dt_phy_config(9)
• ksz_handle_wake_reason(9)
• ksz_is_port_mac_global_usable(9)
• ksz_get_wol(9)
• ksz_set_wol(9)
• ksz_wol_pre_shutdown(9)
• ksz_switch_macaddr_get(9)
• ksz_switch_shutdown(9)
• ksz_drive_strength_to_reg(9)
• ksz_drive_strength_error(9)
• ksz_drive_strength_write(9)

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no cap, that's a lot of see-alsos. read them all or don't, but they're there for you bestie 🍓

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and that's the page!! 💜 this gem came out of ./drivers/net/dsa/microchip, dated October 2026 — so yeah, mark your calendar, the future is already here. stay hydrated, go register a bus, mwah 💋