sof_ipc_send_msg(9)

💅 sof_ipc_send_msg(9) 💅

okay so bestie, we're in the Kernel API Manual section today and the star of the show is sof_ipc_send_msg — literally the generic function that preps and sends one (1) IPC message. that's it, that's the whole vibe. 🎀

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✨ SYNOPSIS ✨

int sof_ipc_send_msg (struct snd_sof_dev *sdev , void *msg_data , size_t
msg_bytes , size_t reply_bytes );

yes she takes four args and returns an int, no cap. 🫶

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🌸 ARGUMENTS 🌸

• sdev — pointer to the SOF core device struct. like, the whole device. the main character. 👑
• msg_data — pointer to a message to send. this is the actual message going out the door. ✨
• msg_bytes — number of bytes in the message. how big is she? 🔥
• reply_bytes — number of bytes available for the reply. important lore: the buffer for the reply data is not passed to this function — the available size is just, like, information for the reply handling functions. iykyk. 💅

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🦋 DESCRIPTION 🦋

on success the function returns 0. otherwise it returns a negative error number. 😭 that's the whole description fr fr, she's short and to the point.

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⭐ NOTE ⭐

higher level sdev->ipc->tx_mutex must be held to make sure that transfers are synchronized. do not skip this, bestie — it's giving "i forgot the mutex" and that's not the energy we want. 💀

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🌈 SEE ALSO 🌈

• Kernel file ./sound/soc/sof/ipc.c — go read her, she has the receipts. 🍓

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that's the page!! 🧚 sign-off time: this one lives in ./sound/soc/sof, dated October 2026, and it was iconic of her honestly. periodt. 💜🎀