dmub_srv_wai...r_inbox_free(9)

📦 version 7.3.1, in nixpkgs unstable

💅 dmub_srv_wait_for_inbox_free — the Kernel API Manual tea 🫖

okay so bestie, welcome to the <pink>Kernel API Manual</pink> page for dmub_srv_wait_for_inbox_free (yeah the header abbreviates it as dmub_srv_wai...r_inbox_free(9) because apparently even manpage headers need to keep it cute and short ✨). Anyway, pull up a chair, this one's literally just "wait for the DMUB inbox to have room" and it's lowkey iconic for it 💅

🌸 NAME 🌸

dmub_srv_wait_for_inbox_free — it waits for space in the DMUB inbox to free up. That's it, that's the whole vibe. The way that function just sits there until there's room 😭 queen behavior fr fr.

✨ SYNOPSIS ✨

enum dmub_status dmub_srv_wait_for_inbox_free (struct dmub_srv *dmub ,
uint32_t timeout_us , uint32_t num_free_required );

periodt. that's the signature, copy it exactly, no cap 🎀

🦋 ARGUMENTS 🦋

  • dmub — the dmub service 💖 like, the whole service struct, your main character here.
  • timeout_us — the maximum number of microseconds to wait ⏳ because we are not about to spin forever, bestie, that's giving toxic loop energy.
  • num_free_required — number of free entries required 🧚 how much room we need before we can chill.

💜 DESCRIPTION 💜

So the function waits until the DMUB buffer is freed to the specified number. That's num_free_required, in case you were wondering 👀 And the maximum wait time is given in microseconds — that's timeout_us — specifically to prevent spinning forever. Not me spinning forever waiting for my crush to text back, but this function is smarter than me, it has a timeout 🙈

That's genuinely the entire description, bestie. It waits, it has a limit, it does not spin into the void. Slay.

🔥 RETURN 🔥

Here's the vibe check on what you get back:

  • DMUB_STATUS_OK — success 🎉 you ate, there was room.
  • DMUB_STATUS_TIMEOUT — the wait for buffer to flush timed out 💀 literally ran out of microseconds, no room found in time.
  • DMUB_STATUS_INVALID — unspecified error 😭 something went wrong but nobody's saying what. mysterious. main character energy.

👑 SEE ALSO 👑

Okay this is the long part and ngl it's a whole friend group, so buckle up 🎀

Kernel file ./drivers/gpu/drm/amd/display/dmub/dmub_srv.h — that's the home base 🏠

Then the whole squad:

like, the whole roster 💅 iykyk.

⭐ friendly reminder: every single one of those is (9), which means kernel API section. don't come for me if you skip one, the group chat will notice 🫶

🎀 sign-off 🎀

this iconic little page lives at ./drivers/gpu/drm/amd/display/... (yes, the source path is abbreviated with ..., it's mysterious like that 💀), dated October 2026, and it answers to dmub_srv_wai...r_inbox_free(9) — same abbreviated name as the top, full circle, we love consistency 🌈

bye bestie, go wait for your inbox to free up responsibly 💖✨

📦 where this page comes from