usb4_port_asym_start(9)

📦 version 7.3.1, in nixpkgs unstable

💅 usb4_port_asym_start ✨

okay so bestie, you found the kernel API manual page for usb4_port_asym_start — this is a function from the Thunderbolt kernel API docs, and honestly? she's a little diva who makes the link change its whole vibe and then waits around for it to finish. icon behaviour, no cap 🎀

🌸 NAME 🌸

usb4_port_asym_start — start the symmetry change and wait for it to complete 💖

🦋 SYNOPSIS 🦋

int usb4_port_asym_start (struct tb_port *port );

✨ ARGUMENTS ✨

  • port — the USB4 port, aka the main character we're doing all this for 🫶

👑 DESCRIPTION 👑

So here's the tea ☕ — usb4_port_asym_start starts the symmetry change of the link, flipping it to asymmetric or symmetric according to whatever you previously set in tb_port_set_link_width. Then it waits for the change to complete. That's it, that's the whole job. She sets the vibe, then she sits there patiently until the link actually commits to it 💅

ngl bestie, "waits for completion" means this call can actually take a hot minute — the -ETIMEDOUT in RETURN is not decorative 😭

🔥 RETURN 🔥

  • 0 — symmetry change was successful, slay 🎉
  • -ETIMEDOUT — timeout occurred, the change did not finish in time 💀
  • Negative errno — some other failure occurred 🙈

🌈 SEE ALSO 🌈

Kernel file: ./drivers/thunderbolt/usb4.c — go read the source, it's giving homework but make it fun 📚✨

okay that's the whole page, you ate that 🍓 this one lives in ./drivers/thunderbolt, dated October 2026 — so mark your calendar bestie, she's from the future 💜💫 go forth and change some link symmetry, iykyk 🧚‍♀️

📦 where this page comes from