xudc_write32(9)

📦 version 7.3.1, in nixpkgs unstable

💅 xudc_write32 — little endian write to device registers

okay so bestie, you're in the Kernel API Manual (section 9, the kernel-API girlies ✨) and today's main character is xudc_write32. it does exactly one thing and it does it iconically: a little endian write to device registers. no cap, that's the whole vibe. 🎀

🦋 SYNOPSIS

void xudc_write32 (void __iomem *addr , u32 offset , u32 val );

like, three little args and you're done. it returns void — nothing comes back, it's giving "I don't do follow-ups" energy 💅

🌸 ARGUMENTS

  • addr — the base addr of the device registers 🏠 this is your home base, your main character address, the __iomem pointer where all the register goodness lives.
  • offset — the register offset 📍 like, which register inside that base you're sliding into. it's a u32.
  • val — the data to be written ✍️ the actual u32 payload. the thing you're putting out into the world. slay.
fr fr, that's the whole contract: base + offset + value, write it out little endian, and dip. 🙈

👑 SEE ALSO

bestie. buckle up. the whole Xilinx UDC family is here and honestly it's a lot of people at this party 🫶 — the kernel file lives at ./drivers/usb/gadget/udc/udc-xilinx.c (go read her, she's the source of truth 🍓) and she links out to:

like yes, that's 47 functions, we counted, we're not okay about it 😭 but honestly? every single one of them is worth a lil scroll. iykyk. 🔥

and that's the whole page, babe 💖 you understood it, you're basically a kernel dev now, periodt. 🌈

from the ./drivers/usb/gadget/udc source (dated October 2026), with love, shipped straight from the Kernel API Manual 🧚⭐ — go write some registers, bestie, go be iconic 💜

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