phy_poll_reset(9)

📦 version 7.3.1, in nixpkgs unstable

okay so bestie, welcome to phy_poll_reset(9) from the Kernel API Manual 🫶✨ this one is literally about waiting for a PHY reset to finish properly instead of rushing in and causing chaos. 💅

💖 NAME 💖

phy_poll_reset — safely wait until a PHY reset has properly completed 🎀

✨ SYNOPSIS ✨

int phy_poll_reset (struct phy_device *phydev );

🎀 ARGUMENTS 🎀

  • phydev — the PHY device to poll. that’s the cutie we’re checking on, no cap 💖

🦋 DESCRIPTION 🦋

okay so according to IEEE 802.3, Section 2, Subsection 22.2.4.1.1, as published in 2008, a PHY reset may take up to 0.5 seconds. the MII BMCR register must be polled until the BMCR_RESET bit clears. periodt. ⏳

also? any attempts to write to PHY registers may have no effect or even generate MDIO bus errors until this is complete. so like… do not rush her, bestie 😭

some PHYs (such as the Marvell 88E1111) don’t entirely conform to the standard and do not fully reset after the BMCR_RESET bit is set, and may even REQUIRE a soft-reset to properly restart autonegotiation. yes, REQUIRE in all caps, she’s dramatic but valid 💅

in an effort to support such broken PHYs, this function is separate from the standard phy_init_hw which will zero all the other bits in the BMCR and reapply all driver-specific and board-specific fixups. so phy_poll_reset is doing its own little waiting ritual, not the whole phy_init_hw reset-and-reapply-everything situation. fr fr 🌸

🌈 SEE ALSO 🌈

Kernel file: ./drivers/net/phy/phy_device.c

💖 cute sign-off: this page lives in ./drivers/net/phy, is dated October 2026, and answers to phy_poll_reset(9) — mwah 💋✨

📦 where this page comes from