__phy_package_read_mmd(9)

💅 __phy_package_read_mmd

ok so real talk, this is a page from the Kernel API Manual and honestly? it's a little guy that does one job and does it cute. bestie, let's get into it 🫶

---

✨ NAME ✨

__phy_package_read_mmd — read an MMD reg, but like... relative to the PHY package base addr 💫

---

🌸 SYNOPSIS 🌸

int __phy_package_read_mmd (struct phy_device *phydev , unsigned int
addr_offset , int devad , u32 regnum );

like, it takes four things and gives you back an int. no cap. 🎀

---

🦋 ARGUMENTS 🦋

• phydev — the phy_device struct 💖 the main character of this whole situation, honestly.
• addr_offset — the offset that gets added onto the PHY package base_addr. yes, added. math is happening. iykyk 🔥
• devad — which MMD you're reading from. pick your fighter ✨
• regnum — the register on that MMD you wanna read. this is u32, respect the width 💅

---

🌈 DESCRIPTION 🌈

okay so picture this: it's a convenience helper for reading a register of an MMD on a given PHY, and it does it using the PHY package base address. iconic behaviour, truly. 🌟

the base address gets added to the addr_offset value — so base_addr + addr_offset, every single time, that's the whole vibe. 🧚

and here's the part where i need you to pay attention bestie: same calling rules as for __phy_read — literally fr fr, don't get creative with it 🙈

---

⭐ NOTE ⭐

it's assumed that the entire PHY package is either C22 or C45. one or the other, queen. don't be messy about it 💀

no cap, this is an assumption — so if your package is some cursed mix, that's on you, not on the helper 🍓

---

🔥 SEE ALSO 🔥

kernel file ./drivers/net/phy/phy_package.c (yes, the struct lives there, go look 🎀), plus the whole squad:

• phy_package_shared(9)
• phy_package_lock(9)
• phy_package_unlock(9)
• __phy_package_write_mmd(9) — the write-flavoured sibling, obsessed with her 💜
• phy_package_join(9)
• of_phy_package_join(9)
• phy_package_leave(9)
• devm_phy_package_join(9)
• devm_of_phy_package_join(9)

---

and that's the page!! sourced from ./drivers/net/phy, dated October 2026, and honestly this doc ate and left no crumbs 👑 mwah 💋