cdns_i2c_master_xfer_atomic(9)

📦 version 7.3.1, in nixpkgs unstable

💅 cdns_i2c_master_xfer_atomic — Kernel API Manual ✨

okay so bestie, you know how the kernel sometimes needs to do i2c stuff but like… it's already in atomic context and can't go to sleep? 😴🚫 this is That Function. it's the atomic-mode transfer girlie, and honestly she ate. let's get into it 🫶

🌸 NAME 🌸

cdns_i2c_master_xfer_atomic — the i2c transfer function, but in atomic mode ⚡ (no sleeping on the job, we simply do not nap here)

✨ SYNOPSIS ✨

int cdns_i2c_master_xfer_atomic (struct i2c_adapter *adap , struct
i2c_msg *msgs , int num );

it returns an int, and it takes three things: an adapter pointer, a message pointer, and a count. that's it. that's the whole vibe check 💅

🎀 ARGUMENTS 🎀

  • adap — pointer to the i2c adapter driver instance 🌈 like, the actual adapter you're talking through, the main character of the hardware situation
  • msgs — pointer to the i2c message structure 💌 the message(s) you wanna send, chillin' in a struct
  • num — the number of messages to transfer 🔢 literally just count them, girl

🔥 RETURN 🔥

  • number of msgs processed on success ✅ slay, it worked
  • negative error otherwise 😭 something went wrong, and it's telling you in negative numbers (as is tradition)

🦋 SEE ALSO 🦋

the kernel file that's serving the whole time: ./drivers/i2c/busses/i2c-cadence.c

and like, the whole friend group 👑:

ngl bestie, if you're calling the non-atomic version while you're already in atomic context, that's a 💀 moment. this one's here for exactly that reason. iykyk ✨

okay that's the whole page, go be iconic with it 🧚‍♀️💜 this gem lives under ./drivers/i2c/busses and the manual's dated October 2026 — fr fr, marking my calendar already 🎀🫶 ✨ bye bestie, go process those msgs ✨

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