comedi_8254_mm_alloc(9)

📦 version 7.3.1, in nixpkgs unstable

✨ comedi_8254_mm_alloc(9) ✨

okay so bestie, welcome to the Kernel API Manual entry for comedi_8254_mm_alloc — yes that's the whole name, yes it's a mouthful, no we're not renaming it 💅

🎀 NAME 🎀

comedi_8254_mm_alloc — the function that allocates and initializes the 8254 device so it can do mmio access. that's it, that's the whole gig. iconic behaviour honestly 🫶

🌸 SYNOPSIS 🌸

struct comedi_8254 * comedi_8254_mm_alloc (void __iomem *mmio , unsigned
int osc_base , unsigned int iosize , unsigned int regshift );

like, look at her. four args, one struct pointer coming back. she's got range 💖

🦋 ARGUMENTS 🦋

  • mmio — the memory mapped I/O base address. this is the whole starting point of the vibe, the address everything else hangs off of ✨
  • osc_base — the base time of the counter in ns. and listen — this one is OPTIONAL. she's only used by comedi_8254_cascade_ns_to_timer, so if that's not your situation you can literally leave her be 🙈
  • iosize — the I/O register size. how big the registers are, no cap 📏
  • regshift — the register gap shift. the gap between registers, shifted. yes that's the actual description, she's mysterious like that 🧚

🔥 RETURN 🔥

you get back either:

  • a pointer to a struct comedi_8254 — slay, we love a success story 👑
  • or an ERR_PTR value — the "something went sideways" option 😭 check it, fr fr, don't just raw-dog the pointer

💜 SEE ALSO 💜

go read the actual source if you want the full lore, it lives right here:

Kernel file ./drivers/comedi/drivers/comedi_8254.c

and the whole 8254 friend group, all of them, not skipping a single one:

ngl comedi_8254_io_alloc(9) is giving sibling energy to this exact page — if you're not doing mmio, go check her out 💅

and that's the page bestie!! 🍓 before you go — shoutout to the source and version, which live over at ./drivers/comedi/drivers, and the date on this one is October 2026. write that down, put it on the fridge, periodt ⭐🎀

📦 where this page comes from