tb_port_pat...n_downstream(9)

💅 tb_port_pat...n_downstream(9) — like, the Kernel API Manual page, bestie ✨

okay so this is one of those kernel API manual pages (yes the truncated-looking title is literally the title, tb_port_pat...n_downstream(9), no I'm not kidding, that's just how it renders 🫶) and it's honestly so niche and so specific and I'm obsessed.

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🌸 NAME 🌸

tb_port_path_direction_downstream — the little function that checks if a path is directed downstream. that's it. that's the whole vibe check 💅

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✨ SYNOPSIS ✨

bool tb_port_path_direction_downstream (const struct tb_port *src ,
       const struct tb_port *dst );

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🎀 ARGUMENTS 🎀

• src — the source adapter. literally where the path starts, bestie 🌸
• dst — the destination adapter. where the path is headed, no cap 🦋

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👑 RETURN 👑

returns true only if the specified path from the source adapter (src) to the destination adapter (dst) is directed downstream.

fr fr, only if. like it's not out here handing out true for just any direction — downstream or nothing 💀

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🔥 SEE ALSO 🔥

the whole friend group, gathered for you 🫶 (all from the kernel file ./drivers/thunderbolt/tb.h):

• 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 usb4_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_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)

like, that's a whole squad right there 🌈 go read them, iykyk 💜

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sign-off time 🎀 this iconic little page lives in ./drivers/thunderbolt, it's dated October 2026, and it's part of the Kernel API Manual — mwah, sending you all the downstream energy, bestie 💖✨🧚‍♀️