mdiobus_modify(9)

📦 version 7.3.1, in nixpkgs unstable

🦋 mdiobus_modify(9) — the Kernel API Manual, but make it make sense 💅

okay so bestie, this is mdiobus_modify from the Kernel API Manual, and honestly? it's giving "little helper function that does exactly what it says on the tin" ✨

🌸 NAME 🌸

mdiobus_modify — a convenience function for modifying a given mdio device register 🎀

like, it's literally right there in the name. modify. mdio. bus. slay.

✨ SYNOPSIS ✨

int mdiobus_modify (struct mii_bus *bus , int addr , u32 regnum , u16
mask , u16 set );

that's the whole vibe check 👑 five args, one int back. no cap.

💖 ARGUMENTS 💖

  • bus — the mii_bus struct 🚌 like, the actual bus you're messing with
  • addr — the phy address 📍
  • regnum — register number to write ✍️ the one you're targeting
  • mask — bit mask of bits to clear 🧹 these bits get wiped
  • set — bit mask of bits to set 🌟 these bits get lit up

so it's mask-then-set, clear-then-set, classic read-modify-write energy fr fr 💅

🔥 RETURN 🔥

0 on success, negative on any error condition 😭

bestie pls check the return value. negative means something went wrong. do NOT ignore it, i'm begging 🙈

🌈 SEE ALSO 🌈

Kernel file ./drivers/net/phy/mdio_bus.c — and the whole friend group:

yeah that's a lot of siblings. it's giving big family energy 🫶 iykyk.

anyway that's the page!! go forth and modify your registers responsibly 💜

okay and before i go — this lil masterpiece lives in ./drivers/net/phy, dated October 2026, straight out of the Kernel API Manual. mwah 💋 see u in the next manpage bestie ⭐🧚‍♀️

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