tb_for_each_port_on_path(9)

🌈 tb_for_each_port_on_path(9) — like, the actual Kernel API Manual, bestie ✨

okay so picture this: you're deep in the Thunderbolt driver, you're in ./drivers/thunderbolt/tb.h, and you need to look at every single port along a path. That's this. This is the one. This is tb_for_each_port_on_path(9) from the Kernel API Manual and honestly? iconic. 💅

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✨ NAME ✨

tb_for_each_port_on_path — iterate over each port on path 🦋

like, one port at a time, all the way down the path. no cap.

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🎀 SYNOPSIS 🎀

tb_for_each_port_on_path (src , dst , p );

three things go in, the walking happens, you get your ports. periodt. 💖

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🌸 ARGUMENTS 🌸

• src — the source port, aka where the path starts. our beginning. main character energy. 👑
• dst — the destination port, aka where the path ends up. the whole point of the journey. ⭐
• p — the port that gets used as the iterator. it's the little guy that moves along while you loop, so don't go messing with it mid-iteration, iykyk. 🔥

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💜 DESCRIPTION 💜

It walks over each port on the path from src to dst. 🚶‍♀️

That's it. That's the whole vibe. You give it a start, you give it an end, you give it an iterator, and it hands you the ports along the way one by one. lowkey perfect.

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🫶 SEE ALSO 🫶

the whole friend group showed up, fr fr. everything below lives in 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_port_path_direction_downstream(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)

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ok that's the whole page bestie, go iterate some ports responsibly 💀

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and that's a wrap!! 🎀 this little gem comes from ./drivers/thunderbolt, dated October 2026, and it's tb_for_each_port_on_path(9) forever and always. mwah. 💖✨