ksz_parent_mdio_write(9)

💅 ksz_parent_mdio_write(9) — like, the Kernel API Manual bestie ✨

okay so bestie, welcome to the Kernel API Manual page for ksz_parent_mdio_write — yes that whole name, we're saying it with our chest 🫶

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🌸 NAME 🌸

ksz_parent_mdio_write — literally just writes data to a PHY register on the parent MDIO bus. that's the whole vibe, no cap 💅

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✨ SYNOPSIS ✨

int ksz_parent_mdio_write (struct mii_bus *bus , int addr , int regnum ,
u16 val );

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🎀 ARGUMENTS 🎀

• bus — the MDIO bus structure. the actual bus, the main character 🌈
• addr — PHY address on the parent MDIO bus. where we're headed, iykyk
• regnum — the register number you're writing to. pick your fave 🔥
• val — the value going into that PHY register. the payload, the moment 💖

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🦋 DESCRIPTION 🦋

so this function is giving direct write operation on the parent MDIO bus for accessing PHY registers. and the way it does it? it bypasses SPI or I2C entirely — not me skipping the whole middleman 😭 — and uses the parent MDIO bus to modify the PHY register values at the specified address. lowkey iconic, highkey efficient ✨

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⭐ RETURN ⭐

0 on success, or a negative error code on failure. slay when it works, and when it doesn't... well, negative error code. we move 🥲

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👑 SEE ALSO 👑

bestie go look at the Kernel file ./drivers/net/dsa/microchip/ksz_common.c — that's the source, the origin story 🫶

and then the whole friend group of related functions, in order, because we do not skip anyone:

• 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_phy_addr_to_port(9)
• ksz_irq_phy_setup(9)
• ksz_irq_phy_free(9)
• ksz_parse_dt_phy_config(9)
• ksz_mdio_register(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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ngl, that's a long SEE ALSO and every single one of them ate 💀💅

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and that's the page, bestie!! 🎀 sourced from ./drivers/net/dsa/microchip, stamped October 2026 — so go forth, write that PHY register at that address, and remember: SPI and I2C did not get an invite 🦋✨💖 periodt.