usb4_switch_read_uid(9)

📦 version 7.3.1, in nixpkgs unstable

💅 usb4_switch_read_uid — the kernel API manual, bestie edition ✨

okay so this is a page from the Kernel API Manual, and it's about usb4_switch_read_uid — literally the tiniest little function and yet she has the whole friend group in SEE ALSO. we love a social butterfly 🦋

🌸 NAME 🌸

usb4_switch_read_uid — reads the UID from a USB4 router, no cap 💖

✨ SYNOPSIS ✨

int usb4_switch_read_uid (struct tb_switch *sw , u64 *uid );

that's it. that's the whole vibe. two args, one int coming back at you 🎀

🫶 ARGUMENTS 🫶

  • sw — the USB4 router in question 👑 this is the one you're reading from
  • uid — the UID gets stored here 🍓 like, you hand her a pointer and she fills it in, that's the whole deal

💜 DESCRIPTION 💜

Reads the 64-bit UID from USB4 router config space. that's the tea ☕ — config space, 64 whole bits of UID, straight off the router. she's not doing anything fancy, she's just fetching the goods and dropping them where you told her to 🌈

⭐ RETURN ⭐

  • 0 on success — slay 💅
  • negative errno otherwise — not slay 😭

🧚 SEE ALSO 🧚

okay bestie, buckle up, because this list is long — she knows everyone. the kernel file lives at ./drivers/thunderbolt/usb4.c, and here's the whole squad:

like I said. everyone. 🔥

ngl, if you're poking at USB4 router config space you're already kind of a main character 🎀

and that's the whole page, bestie!! this one comes out of ./drivers/thunderbolt, dated October 2026, and it's part of the Kernel API Manual — usb4_switch_read_uid(9) fr fr 💖✨🫶

📦 where this page comes from