stmmac_mdio_write_c22(9)

💅 NAME

stmmac_mdio_write_c22 — bestie, this is the c22 (clause 22, the O.G. MDIO vibe) write hook for the stmmac driver. The manpage gives us literally zero extra prose here, so we're just gonna say it with our chest: it's the function that pushes data into an MII register. Slay. ✨

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🎀 SYNOPSIS

int stmmac_mdio_write_c22 (struct mii_bus *bus , int phyaddr , int
phyreg , u16 phydata );

That's the whole signature, no cap. Four args, one int coming back atcha. 🫶

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🌸 ARGUMENTS

• bus — points to the mii_bus structure 💖 like, this is the bus we're doing the writing on, periodt.
• phyaddr — MII addr 🌈 the address of the PHY we're talking to. Lowkey important.
• phyreg — MII reg 🎀 which register inside that PHY is getting the goods.
• phydata — phy data ✨ the actual u16 payload. This is the moment. The main character.

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🦋 DESCRIPTION

okay so, real talk: it writes the data into the MII register from within the device. 💅 That's it, that's the whole description, and honestly the source said it best so we're keeping it exactly. The data goes in, the register gets it, the device does its thing. Iconic behaviour, fr fr. 🔥

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👑 SEE ALSO

• Kernel file ./drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c — the actual home of all this magic, go read it iykyk 📖
• stmmac_mdio_format_addr(9)
• stmmac_mdio_read_c22(9)
• stmmac_mdio_read_c45(9)
• stmmac_mdio_write_c45(9)
• stmmac_mdio_reset(9)
• stmmac_clk_csr_set(9)
• stmmac_mdio_register(9)
• stmmac_mdio_unregister(9)

like the whole stmmac_mdio friend group, we love a supportive squad 🫶💜

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ngl, if you came here looking for a 40-flag options list, this page is not that girl — the original had no options section and neither do we. Facts only, bestie. 💀

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that's a wrap! 🌸 brought to you by ./drivers/net/ethernet/stmicro... vibes, dated October 2026, and yes we're still serving stmmac_mdio_write_c22(9) energy. mwah 💋✨