usb4_port_router_online(9)

💅 usb4_port_router_online — the Kernel API Manual, bestie edition 🎀

okay so like, this page lives in the Kernel API Manual, and honestly? it's a short one. she's lowkey a one-liner icon and we respect her for it. ✨

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🌸 NAME 🌸

usb4_port_router_online — put the USB4 port back online, no cap 🫶

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⭐ SYNOPSIS ⭐

int usb4_port_router_online (struct tb_port *port );

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🦋 ARGUMENTS 🦋

• port — the USB4 port in question, bestie. that's the one we're bringing back to life 💖

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👑 DESCRIPTION 👑

so the whole vibe here is: this function makes the USB4 port functional again. that's it. that's the plot. she's back online, she's serving, she's literally doing her job again 🔥

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🌈 RETURN 🌈

• 0 on success — slay 💅
• a negative errno otherwise — not slay, but at least you know what happened 😭

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🧚 SEE ALSO 🧚

the kernel file is ./drivers/thunderbolt/usb4.c and omg there are so many friends in this group chat. go say hi to all of them:

• 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) ← the other one, the prequel 💀
• 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(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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fr fr that's the whole page. it's giving "short and sweet and knows exactly what it's about." iykyk 💜

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and that's a wrap bestie!! this one came from the source dir ./drivers/thunderbolt, dated October 2026, and the manual page is usb4_port_router_online(9). mwah, go touch some USB4 hardware 🍓✨💖