snd_hdac_ext_stream_assign(9)

📦 version 7.3.1, in nixpkgs unstable

💅 snd_hdac_ext_stream_assign(9) — the Kernel API Manual, bestie edition 🎀

okay so this is a page from the Kernel API Manual and it's all about snd_hdac_ext_stream_assign(9) — the little function that hands your PCM a stream. literally the matchmaker of HD-audio 💖

✨ NAME ✨

snd_hdac_ext_stream_assign — assign a stream for the PCM 🎧

🦋 SYNOPSIS 🦋

struct hdac_ext_stream * snd_hdac_ext_stream_assign (struct hdac_bus
*bus , struct snd_pcm_substream *substream , int type );

it's giving "three args and a dream" ngl ✨

🌸 ARGUMENTS 🌸

  • bus — the HD-audio core bus, aka the whole vibe headquarters 🏠
  • substream — the PCM substream you want to assign, the main character of this operation 👑
  • type — the type of stream (coupled, host or link stream) — pick your fighter 💅

⭐ DESCRIPTION ⭐

so here's the tea ☕: this function assigns the stream based on the type (coupled/host/link), for the given PCM substream, assigns it, and returns the stream object. yes, it said "assigns" twice, that's just how committed it is 🫶

here's how each type gets matched up:

  • coupled: looks for an unused stream
  • host: looks for an unused decoupled host stream
  • link: looks for an unused decoupled link stream

if no stream is free, it returns NULL 😭 — no stream, no vibes.

the function tries to keep using the same stream object when it's used beforehand — lowkey loyal fr fr 💖. and when a stream is decoupled, it becomes a host stream and a link stream. it's giving "two jobs, one icon" ✨

🌈 SEE ALSO 🌈

the kernel file lives right here, bestie:

  • ./sound/hda/core/ext/stream.c

and the whole friend group 👯:

🫶 that's the whole page, no cap. go assign some streams, you're gonna slay.

mwah 💋 this came from ./sound/hda/core/ext, dated October 2026, and it's snd_hdac_ext_stream_assign(9) — periodt. 🎀

📦 where this page comes from