sdio_retune_hold_now(9)

💅 sdio_retune_hold_now 💅

ok so this is a page from the Kernel API Manual, and honestly bestie, it's a little two-function wonder that solves a very specific "not right now" problem 🫶

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✨ NAME ✨

sdio_retune_hold_now — start deferring retuning requests till release 🌸

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✨ SYNOPSIS ✨

void sdio_retune_hold_now (struct sdio_func *func );

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✨ ARGUMENTS ✨

• func — the SDIO function that's attached to the host 👑

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✨ DESCRIPTION ✨

okay so picture this: it is currently a bad time to do a retune of the SDIO card 💀 and if that's the case, you can call this function. Any retune requests that get made during this window will be held — like, politely waiting in the group chat — and we'll actually do the retune sometime after the release. no cap, it just queues them up 🎀

this function could be useful if an SDIO card is in a power state where it can respond to a small subset of commands that doesn't include the retuning command. iykyk 🧚

⚠️ care should be taken when using this function, since (presumably) the retuning request we might be deferring was made for a good reason. like, someone had a reason bestie. respect the reason. 🙈

this function should be called while the host is claimed. periodt ✋

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✨ SEE ALSO ✨

kernel file ./drivers/mmc/core/sdio_io.c — and like, the whole squad 💜

• sdio_claim_host(9)
• sdio_release_host(9)
• sdio_enable_func(9)
• sdio_disable_func(9)
• sdio_set_block_size(9)
• sdio_align_size(9)
• sdio_readb(9)
• sdio_writeb(9)
• sdio_writeb_readb(9)
• sdio_memcpy_fromio(9)
• sdio_memcpy_toio(9)
• sdio_readsb(9)
• sdio_writesb(9)
• sdio_readw(9)
• sdio_writew(9)
• sdio_readl(9)
• sdio_writel(9)
• sdio_f0_readb(9)
• sdio_f0_writeb(9)
• sdio_get_host_pm_caps(9)
• sdio_set_host_pm_flags(9)
• sdio_retune_crc_disable(9)
• sdio_retune_crc_enable(9)
• sdio_retune_release(9)

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okay that's the whole page!! 💖 it lives in ./drivers/mmc/core, it's dated October 2026, and yeah — sdio_retune_hold_now(9), that's her, that's the icon 👑✨