phy_inband_caps(9)

okay so bestie, this is phy_inband_caps(9) — a page from the Kernel API Manual, and we’re SO glad you’re here 💅✨

💖 NAME 💖

phy_inband_caps — query which in-band signalling modes are supported

✨ SYNOPSIS ✨

unsigned int phy_inband_caps (struct phy_device *phydev ,
phy_interface_t interface );

🎀 ARGUMENTS 🎀

• phydev — a pointer to a struct phy_device
• interface — the interface mode for the PHY

🦋 DESCRIPTION 🦋

So this one is doing the in-band vibe check. It returns zero if it is unknown what in-band signalling is supported by the PHY — for example, because the PHY driver doesn’t implement the method. No data, no cap. 😭

Otherwise, it returns a bit mask of the LINK_INBAND_* values from enum link_inband_signalling to describe which inband modes are supported by the PHY for this interface mode. Bit mask reveal, iconic. ✨

👑 SEE ALSO 👑

Kernel file ./drivers/net/phy/phy.c — and honestly the whole PHY bestie group chat is here:

• phy_print_status(9)
• phy_get_rate_matching(9)
• phy_config_interrupt(9)
• phy_restart_aneg(9)
• phy_aneg_done(9)
• phy_supported_speeds(9)
• phy_check_valid(9)
• phy_sanitize_settings(9)
• phy_mii_ioctl(9)
• phy_do_ioctl(9)
• phy_do_ioctl_running(9)
• __phy_hwtstamp_get(9)
• __phy_hwtstamp_set(9)
• phy_queue_state_machine(9)
• phy_trigger_machine(9)
• phy_ethtool_get_strings(9)
• phy_ethtool_get_sset_count(9)
• phy_ethtool_get_stats(9)
• __phy_ethtool_get_phy_stats(9)
• __phy_ethtool_get_link_ext_stats(9)
• phy_ethtool_get_plca_cfg(9)
• plca_check_valid(9)
• phy_ethtool_set_plca_cfg(9)
• phy_ethtool_get_plca_status(9)
• phy_start_cable_test(9)
• phy_start_cable_test_tdr(9)
• phy_check_link_status(9)
• phy_config_inband(9)
• _phy_start_aneg(9)
• phy_start_aneg(9)
• phy_speed_down(9)
• phy_speed_up(9)
• phy_start_machine(9)
• phy_stop_machine(9)
• phy_error(9)
• phy_write_barrier(9)
• phy_disable_interrupts(9)
• phy_interrupt(9)
• phy_enable_interrupts(9)
• phy_update_stats(9)
• phy_request_interrupt(9)
• phy_free_interrupt(9)
• phy_get_next_update_time(9)
• phy_state_machine(9)
• phy_stop(9)
• phy_start(9)
• phy_mac_interrupt(9)
• phy_loopback(9)
• phy_eee_tx_clock_stop_capable(9)
• phy_eee_rx_clock_stop(9)
• phy_init_eee(9)
• phy_get_eee_err(9)
• phy_ethtool_get_eee(9)
• phy_ethtool_set_eee_noneg(9)
• phy_ethtool_set_eee(9)
• phy_ethtool_set_wol(9)
• phy_ethtool_get_wol(9)
• phy_ethtool_nway_reset(9)

source/version: ./drivers/net/phy · date: October 2026 — bye bestie, go query those in-band caps 💖🦋