STRUCT MHUV3_PROTOCOL_OPS(9)

💅 struct mhuv3_protocol_ops

okay bestie so this is from the Kernel API Manual, and it's literally the page for struct mhuv3_protocol_ops — the MHUv3 operations vtable. iykyk, it's the little bundle of function pointers that makes the mailbox magic happen ✨

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✨ SYNOPSIS ✨

lowkey just look at it, it's giving function-pointer buffet:

struct mhuv3_protocol_ops {
    int (*rx_startup)(struct mhuv3 *mhu, struct mbox_chan *chan);
    void (*rx_shutdown)(struct mhuv3 *mhu, struct mbox_chan *chan);
    void *(*read_data)(struct mhuv3 *mhu, struct mbox_chan *chan);
    void (*rx_complete)(struct mhuv3 *mhu, struct mbox_chan *chan);
    void (*tx_startup)(struct mhuv3 *mhu, struct mbox_chan *chan);
    void (*tx_shutdown)(struct mhuv3 *mhu, struct mbox_chan *chan);
    int (*last_tx_done)(struct mhuv3 *mhu, struct mbox_chan *chan);
    int (*send_data)(struct mhuv3 *mhu, struct mbox_chan *chan, void
*arg);
 };

no cap, copy it exactly or the compiler will absolutely drag you 🫶

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🎀 Members 🎀

the whole squad, in order

• rx_startup — the Receiver startup callback. when the receiving era begins, this gets the call 📞
• rx_shutdown — the Receiver shutdown callback. wrapping it up on the rx side, periodt.
• read_data — reads whatever available Sender in-band LE data there is (if any!). returns void *, and yes the "(if any)" is doing a lot of heavy lifting there 😭
• rx_complete — acknowledge data reception to the Sender. and here's the important part bestie: any out-of-band data has to have already been retrieved before you call this. like, do not call it early, that's the rule 🙈
• tx_startup — the Sender startup callback. sender girlies rise 🌅
• tx_shutdown — the Sender shutdown callback. bye bye sending era 💀
• last_tx_done — reports back to the Sender whether the last transfer has completed. yes/no energy, very main character 👑
• send_data — sends data to the receiver. takes (struct mhuv3 *mhu, struct mbox_chan *chan, void *arg) and returns an int. that's the whole job, slay 💅

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🌸 Description 🌸

so the vibe here is: every supported transport protocol brings its own implementation of these operations. that's it, that's the whole point — this struct is the plug-and-play contract, and each protocol fills it in with its own flavor 🧚

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🦋 SEE ALSO 🦋

• the kernel file ./drivers/mailbox/arm_mhuv3.c — go read it, it's iconic ⭐
• struct mhuv3_mbox_chan_priv(9)
• struct mhuv3_extension(9)
• struct mhuv3(9)

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and that's the page!! 🍓 found in ./drivers/mailbox, dated October 2026, all about struct mhuv3_protocol_ops(9) — mwah, go forth and implement your protocols bestie 💖🎀