ytphy_utp_config_aneg(9)

✨ ytphy_utp_config_aneg(9) ✨

okay so bestie, this is a page from the Kernel API Manual — yes, that Kernel API Manual — and honestly it's giving "small function, big responsibilities" energy 💅

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🌸 NAME 🌸

ytphy_utp_config_aneg — restart auto-negotiation or write BMCR 🎀

🦋 SYNOPSIS 🦋

int ytphy_utp_config_aneg (struct phy_device *phydev , bool changed );

💖 ARGUMENTS 💖

• phydev — the target phy_device struct, aka the whole reason we're here 💫
• changed — a bool, literally just "whether autoneg is requested" 👑

🔥 NOTE 🔥

okay so listen up, because this part is the actual tea ☕

If auto-negotiation is enabled, we configure the advertising, and then we restart auto-negotiation. Iconic. If it is not enabled, then we write the BMCR. That's it, that's the branch 🌈

⚠️ no cap: the caller must have taken the MDIO bus lock. Like, must. This isn't a suggestion, it's a vibe check you cannot skip 😭

And what does it give you back? It returns 0 or negative errno code. Slay 🫶

👑 SEE ALSO 👑

Kernel file ./drivers/net/phy/motorcomm.c — and honestly the whole friend group 🧚

The ytphy_*_ext girlies (and their lock-free twins):

• ytphy_read_ext(9)
• ytphy_read_ext_with_lock(9)
• ytphy_write_ext(9)
• ytphy_write_ext_with_lock(9)
• ytphy_modify_ext(9)
• ytphy_modify_ext_with_lock(9)

WOL + page stuff:

• ytphy_get_wol(9)
• ytphy_set_wol(9)
• yt8521_read_page(9)
• yt8521_write_page(9)

The structs (yes they get their own (9) and yes that's iconic):

• struct ytphy_cfg_reg_map(9)
• struct ytphy_ldo_vol_map(9)

The yt8521 crew, part 1:

• yt8521_probe(9)
• ytphy_utp_read_lpa(9)
• yt8521_adjust_status(9)
• yt8521_read_status_paged(9)
• yt8521_read_status(9)
• yt8521_modify_bmcr_paged(9)
• yt8521_modify_utp_fiber_bmcr(9)
• yt8521_soft_reset(9)
• yt8521_suspend(9)
• yt8521_resume(9)
• yt8521_config_init(9)

The yt8521 crew, part 2 (fiber era):

• yt8531_link_change_notify(9)
• yt8521_prepare_fiber_features(9)
• yt8521_fiber_setup_forced(9)
• ytphy_check_and_restart_aneg(9)
• yt8521_fiber_config_aneg(9)
• ytphy_setup_master_slave(9)
• ytphy_utp_config_advert(9)

The yt8521 crew, part 3 (aneg & features):

• yt8521_config_aneg_paged(9)
• yt8521_config_aneg(9)
• yt8521_aneg_done_paged(9)
• yt8521_aneg_done(9)
• ytphy_utp_read_abilities(9)
• yt8521_get_features_paged(9)
• yt8521_get_features(9)

The yt8821 crew — main character energy, all of them:

• yt8821_get_features(9)
• yt8821_get_rate_matching(9)
• yt8821_aneg_done(9)
• yt8821_serdes_init(9)
• yt8821_utp_init(9)
• yt8821_auto_sleep_config(9)
• yt8821_soft_reset(9)
• yt8821_config_init(9)
• yt8821_adjust_status(9)
• yt8821_update_interface(9)
• yt8821_read_status(9)
• yt8821_modify_utp_fiber_bmcr(9)
• yt8821_suspend(9)
• yt8821_resume(9)

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okay that's the whole page, you ate that 💅✨

cute lil sign-off: this one lives in ./drivers/net/phy, it's dated October 2026, and it's still answering to the name ytphy_utp_config_aneg(9) — periodt 🎀🦋💜