fsl_rio_doorbell_send(9)

✨ fsl_rio_doorbell_send ✨

Okay bestie, so this is a page straight out of the Kernel API Manual (Kernel API Manual, yeah, that one 💅) and it's all about fsl_rio_doorbell_send — a little function that rings a doorbell. Not your doorbell. A RapidIO doorbell. Hang on, I got you 🫶

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🌸 SYNOPSIS 🌸

int fsl_rio_doorbell_send (struct rio_mport *mport , int index , u16
destid , u16 data );

That's the whole vibe — it's an int-returning function taking four things. Lil function, big job. ⭐

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🎀 ARGUMENTS 🎀

• mport — the RapidIO master port info, like the portal's whole personality ✨
• index — the ID of the RapidIO interface, i.e. which one, bestie
• destid — destination ID of the target device 🎯
• data — the 16-bit info field of the RapidIO doorbell message, aka the actual little payload you're sending 💌

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🦋 DESCRIPTION 🦋

So what does it do?? It sends an MPC85xx doorbell message. That's it, that's the whole arc of the story 🧚

And the return value? Returns 0 on success or -EINVAL on failure. Two outcomes, no in-between, no cap. 🔥

Ngl if you see that -EINVAL bestie, something about your args was NOT it 💀

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🌈 SEE ALSO 🌈

The kernel file lives at ./arch/powerpc/sysdev/fsl_rmu.c and honestly there's a whole friend group over there — go say hi to all of them:

• fsl_rio_tx_handler(9)
• fsl_rio_rx_handler(9)
• fsl_rio_dbell_handler(9)
• fsl_rio_port_write_handler(9)
• fsl_rio_pw_enable(9)
• fsl_rio_port_write_init(9)
• fsl_add_outb_message(9)
• fsl_open_outb_mbox(9)
• fsl_close_outb_mbox(9)
• fsl_open_inb_mbox(9)
• fsl_close_inb_mbox(9)
• fsl_add_inb_buffer(9)
• fsl_get_inb_message(9)
• fsl_rio_doorbell_init(9)

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💖 And that's the page!! This cutie lives under ./arch/powerpc/sysdev and was stamped October 2026 — so like, future iconic behavior. Bye bestie, go ring that doorbell 🎀🦋✨