STRUCT USB4_PORT(9)

✨ NAME ✨

okay so bestie, gather round — this is the manual page for struct usb4_port, which is literally the USB4 port device representation. no cap, it's giving main character energy in the thunderbolt subsystem. 💅

🌈 SYNOPSIS 🌈

here's the exact struct definition, copied character for character because we do not mess with facts:

struct usb4_port {
    struct device dev;
    struct tb_port *port;
    bool can_offline;
    bool offline;
  #ifdef CONFIG_USB4_DEBUGFS_MARGINING;
    struct tb_margining *margining;
  #endif;
};

💅 Members 💅

okay so here's the tea on each member, bestie — don't skip any:

• dev — the device for the port. it's the whole reason this struct exists, honestly. 🫶
• port — pointer to the lane 0 adapter. lowkey important. 🦋
• can_offline — does the port have the necessary platform support to move it into offline mode and back? it's a yes/no vibe check. ⭐
• offline — the port is currently in offline mode. periodt. 💀
• margining — pointer to the margining structure if enabled.

note: this field only exists if CONFIG_USB4_DEBUGFS_MARGINING is defined, so it's conditional, bestie. don't come for me if it's not there. 🙈

🦋 SEE ALSO 🦋

so many references, omg. they're all in the kernel file ./drivers/thunderbolt/tb.h, and here's the full list — iykyk:

• struct tb_nvm(9)
• enum tb_switch_tmu_mode(9)
• struct tb_switch_tmu(9)
• struct tb_switch(9)
• struct tb_bandwidth_group(9)
• struct tb_port(9)
• struct tb_retimer(9)
• struct tb_path_hop(9)
• enum tb_path_port(9)
• struct tb_path(9)
• struct tb_cm_ops(9)
• tb_upstream_port(9)
• tb_is_upstream_port(9)
• tb_port_has_remote(9)
• tb_domain_event(9)
• tb_switch_for_each_port(9)
• tb_switch_downstream_port(9)
• tb_switch_depth(9)
• tb_switch_is_icm(9)
• tb_switch_tmu_is_configured(9)
• tb_switch_tmu_is_enabled(9)
• tb_switch_clx_is_enabled(9)
• tb_port_path_direction_downstream(9)
• tb_for_each_port_on_path(9)
• tb_for_each_upstream_port_on_path(9)
• tb_path_for_each_hop(9)
• tb_downstream_route(9)
• tb_xdomain_downstream_port(9)
• usb4_switch_version(9)
• tb_switch_is_usb4(9)
• enum usb4_sb_target(9)
• enum usb4_margin_sw_error_counter(9)
• struct usb4_port_margining_params(9)

this whole thing lives in ./drivers/thunderbolt, version October 2026, and the manual page is literally called struct usb4_port(9). go off, bestie. 💅✨🎀