genphy_c37_config_advert(9)

💅 genphy_c37_config_advert

okay bestie, real talk: this one is a lil kernel function from the Kernel API Manual, and honestly? it's giving "quietly doing the most." ✨

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🎀 NAME

genphy_c37_config_advert — sanitize and advertise auto-negotiation parameters 🫶

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✨ SYNOPSIS

int genphy_c37_config_advert (struct phy_device *phydev );

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🌸 ARGUMENTS

• phydev — target phy_device struct. that's the PHY you're doing this to, no cap 💖

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🦋 DESCRIPTION

So here's the tea ☕: this function writes MII_ADVERTISE with the appropriate values — but first it sanitizes those values so you only ever advertise what's actually supported. like, it does a lil vibe check on your advertisement before letting it out the door 💅

it returns:

• < 0 on error 😭
• 0 if the PHY's advertisement hasn't changed
• > 0 if it has changed 🔥

✨ important detail, bestie: this function is intended for Clause 37 1000Base-X mode. not your average everyday mode, iykyk.

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👑 SEE ALSO

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

• phy_uses_state_machine(9)
• phy_register_fixup(9)
• genphy_match_phy_device(9)
• get_phy_c45_ids(9)
• get_phy_c22_id(9)
• get_phy_device(9)
• phy_device_register(9)
• phy_device_remove(9)
• phy_get_c45_ids(9)
• phy_find_next(9)
• phy_prepare_link(9)
• phy_connect_direct(9)
• phy_connect(9)
• phy_disconnect(9)
• phy_poll_reset(9)
• phy_sfp_connect_phy(9)
• phy_sfp_disconnect_phy(9)
• phy_sfp_attach(9)
• phy_sfp_detach(9)
• phy_sfp_probe(9)
• phy_attach_direct(9)
• phy_detach(9)
• phy_reset_after_clk_enable(9)
• genphy_config_advert(9)
• genphy_setup_forced(9)
• genphy_restart_aneg(9)
• genphy_check_and_restart_aneg(9)
• __genphy_config_aneg(9)
• genphy_c37_config_aneg(9)
• genphy_aneg_done(9)
• genphy_update_link(9)
• genphy_read_status_fixed(9)
• genphy_read_status(9)
• genphy_c37_read_status(9)
• genphy_soft_reset(9)
• genphy_read_abilities(9)
• phy_remove_link_mode(9)
• phy_advertise_supported(9)
• phy_advertise_eee_all(9)
• phy_support_eee(9)
• phy_disable_eee(9)
• phy_support_sym_pause(9)
• phy_support_asym_pause(9)
• phy_set_sym_pause(9)
• phy_set_asym_pause(9)
• phy_validate_pause(9)
• phy_get_pause(9)
• phy_get_internal_delay(9)
• phy_get_tx_amplitude_gain(9)
• phy_get_mac_termination(9)
• phy_get_sfp_port(9)
• fwnode_mdio_find_device(9)
• fwnode_phy_find_device(9)
• fwnode_get_phy_node(9)
• phy_probe(9)
• phy_driver_register(9)

like okay, go off, entire subsystem 🌈

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and that's the whole page, bestie 💜 it lives over in ./drivers/net/phy, the Kernel API Manual version is dated October 2026, and the page title is genphy_c37_config_advert(9) — periodt. 🍓🧚💫