comedi_8254_io_alloc(9)

📦 version 7.3.1, in nixpkgs unstable

💅 comedi_8254_io_alloc — it's giving "kernel API manual" energy

okay so bestie, welcome to the Kernel API Manual page for comedi_8254_io_alloc(9) — the function that literally allocates and initializes the 8254 device for pio access. that's the whole vibe. pio. port I/O. we love a low-level moment ✨

🎀 NAME 🎀

comedi_8254_io_alloc — allocate and initialize the 8254 device for pio access 🫶

so like, it sets up your 8254 chip so you can poke at it through port I/O. that's it, that's the function, and honestly? iconic.

✨ SYNOPSIS ✨

struct comedi_8254 * comedi_8254_io_alloc (unsigned long iobase ,
       unsigned int osc_base , unsigned int iosize , unsigned int regshift );

yes queen, four arguments, one pointer back, no cap. keep the signature exactly like that 💅

🌸 ARGUMENTS 🌸

  • iobase — the port I/O base address. this is where your chip actually lives, address-wise. main character location fr fr 📍
  • osc_base — base time of the counter, in ns. OPTIONAL! and lowkey only used by comedi_8254_cascade_ns_to_timer. so if you're not doing the cascade thing, she's just vibing there unused 🦋
  • iosize — the I/O register size. how much space we're working with, size-wise.
  • regshift — the register gap shift. the gap between registers, shifted. that's the whole explanation and we're not adding lore that isn't there 💀

👑 RETURN 👑

you get back a pointer to a struct comedi_8254 — or an ERR_PTR value. so, real object or a little error in pointer's clothing. check it before you use it, bestie, please 😭

💖 SEE ALSO 💖

kernel file: ./drivers/comedi/drivers/comedi_8254.c — that's the source, go read it, she's right there 🍓

and the whole 8254 friend group, all of them, no skipping:

the squad. the whole squad. memorise them 🧚

ngl go read the other pages too — this one is just the alloc, the rest is where the actual poking happens 💜

and that's the page!! sign-off time: this cutie comes from ./drivers/comedi/drivers, dated October 2026, and it's filed under comedi_8254_io_alloc(9). periodt 💅🌈⭐

📦 where this page comes from