tb_dp_port_set_hops(9)

📦 version 7.3.1, in nixpkgs unstable

💅 tb_dp_port_set_hops(9)

okay so bestie, welcome to the Kernel API Manual — this one is an entry in section 9 (that's the kernel-functions corner of the man pages, iykyk). Buckle up, we're setting hop IDs on a DisplayPort thingy and honestly? kinda iconic.

✨ NAME ✨

tb_dp_port_set_hops — Set video/aux Hop IDs for DP port

Like, that's the whole vibe. You give it a DP port, you give it hop IDs, it sets them. Slay.

🌸 SYNOPSIS 🌸

int tb_dp_port_set_hops (struct tb_port *port , unsigned int video ,
       unsigned int aux_tx , unsigned int aux_rx );

🎀 ARGUMENTS 🎀

  • port — the DP IN/OUT port we're setting hops on. the main character, fr.
  • video — the Video Hop ID. yes bestie, that's the one for the pixels 🖥️
  • aux_tx — the AUX TX Hop ID. the sending-side AUX sidekick.
  • aux_rx — the AUX RX Hop ID. its receiving counterpart. they're a duo, we don't split them.

🦋 DESCRIPTION 🦋

So what does it actually do? It programs the specified Hop IDs for a DP IN/OUT port. That's it, that's the whole job, and it eats every time 💅

But here's the lowkey important bit: it can be called for USB4 router DP adapters too — but it doesn't actually program the values in that case, because the fields are read-only there. So like… the call goes through, it just doesn't write anything. Not me showing up to a function call that's just vibes 🙈

⚠️ heads up bestie: don't expect hop IDs to change on USB4 router DP adapters, because those fields are read-only. no cap.

🔥 RETURN 🔥

  • 0 on success 🎉
  • negative errno otherwise 😭

👑 SEE ALSO 👑

The kernel file lives at ./drivers/thunderbolt/switch.c, and here's the whole friend group — every single one of them, in order, no gatekeeping:

okay that's the page!! 💖 it comes from the ./drivers/thunderbolt source, dated October 2026, and it's filed under section 9 of the Kernel API Manual. go forth and set those hops, bestie — you're gonna do amazing 🫶✨

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