usb4_port_re...authenticate(9)

💅 usb4_port_retimer_nvm_authenticate — Kernel API Manual ✨

okay bestie, welcome to the usb4_port_retimer_nvm_authenticate(9) page, from the Kernel API Manual itself 🫶 this one's a little baddie that does exactly one job and does it iconically.

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🌸 NAME 🌸

usb4_port_retimer_nvm_authenticate — start the retimer NVM upgrade, no cap 💅

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🎀 SYNOPSIS 🎀

int usb4_port_retimer_nvm_authenticate (struct tb_port *port , u8 index );

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✨ ARGUMENTS ✨

• port — the USB4 port in question, your main character 🌈
• index — the retimer index. yeah. the little number that says which retimer 💫

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🦋 DESCRIPTION 🦋

so here's the vibe: once you've already written the new NVM image in with usb4_port_retimer_nvm_write, this function is what you call to actually trigger the NVM upgrade process. it's giving "the final push" 🎬

if it goes well, the retimer restarts with the new NVM — and heads up, it may not have the index set after that 🙈 so you lowkey need to call usb4_port_enumerate_retimers to force the index to get assigned. don't skip that step, fr fr.

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💖 RETURN 💖

• 0 on success 🥳
• a negative errno otherwise 💀

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🌟 SEE ALSO 🌟

kernel file ./drivers/thunderbolt/usb4.c, plus the whole friend group:

usb4_switch_check_wakes(9), usb4_switch_setup(9), usb4_switch_configuration_valid(9), usb4_switch_read_uid(9), usb4_switch_drom_read(9), usb4_switch_lane_bonding_possible(9), usb4_switch_set_wake(9), usb4_switch_set_sleep(9), usb4_switch_nvm_sector_size(9), usb4_switch_nvm_read(9), usb4_switch_nvm_set_offset(9), usb4_switch_nvm_write(9), usb4_switch_nvm_authenticate(9), usb4_switch_nvm_authenticate_status(9), usb4_switch_credits_init(9), usb4_switch_query_dp_resource(9), usb4_switch_alloc_dp_resource(9), usb4_switch_dealloc_dp_resource(9), usb4_port_index(9), usb4_switch_map_pcie_down(9), usb4_switch_map_usb3_down(9), usb4_switch_add_ports(9), usb4_switch_remove_ports(9), usb4_port_unlock(9), usb4_port_hotplug_enable(9), usb4_port_reset(9), usb4_port_configure(9), usb4_port_unconfigure(9), usb4_port_configure_xdomain(9), usb4_port_unconfigure_xdomain(9), usb4_port_sb_read(9), usb4_port_sb_write(9), usb4_port_router_offline(9), usb4_port_router_online(9), usb4_port_enumerate_retimers(9), usb4_port_clx_supported(9), usb4_port_asym_supported(9), usb4_port_asym_set_link_width(9), usb4_port_asym_start(9), usb4_port_margining_caps(9), usb4_port_hw_margin(9), usb4_port_sw_margin(9), usb4_port_sw_margin_errors(9), usb4_port_retimer_set_inbound_sbtx(9), usb4_port_retimer_unset_inbound_sbtx(9), usb4_port_retimer_is_last(9), usb4_port_retimer_is_cable(9), usb4_port_retimer_nvm_sector_size(9), usb4_port_retimer_nvm_set_offset(9), usb4_port_retimer_nvm_write(9), usb4_port_retimer_nvm_authenticate_status(9), usb4_port_retimer_nvm_read(9), usb4_usb3_port_max_link_rate(9), usb4_usb3_port_allocated_bandwidth(9), usb4_usb3_port_allocate_bandwidth(9), usb4_usb3_port_release_bandwidth(9), usb4_dp_port_set_cm_id(9), usb4_dp_port_bandwidth_mode_supported(9), usb4_dp_port_bandwidth_mode_enabled(9), usb4_dp_port_set_cm_bandwidth_mode_supported(9), usb4_dp_port_group_id(9), usb4_dp_port_set_group_id(9), usb4_dp_port_nrd(9), usb4_dp_port_set_nrd(9), usb4_dp_port_granularity(9), usb4_dp_port_set_granularity(9), usb4_dp_port_set_estimated_bandwidth(9), usb4_dp_port_allocated_bandwidth(9), usb4_dp_port_allocate_bandwidth(9), usb4_dp_port_requested_bandwidth(9), usb4_pci_port_set_ext_encapsulation(9), usb4_pci_port_ltssm_state(9)

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and that's the whole page, bestie 🧚 this lil cutie lives in ./drivers/thunderbolt, dated October 2026, and yeah — it's usb4_port_re...authenticate(9), the icon it is 💜 go forth and authenticate those NVMs, you got this 💅✨