sdio_claim_host(9)

💖 sdio_claim_host — the manual, but make it make sense 💖

okay so this is a page from the Kernel API Manual, and it's about sdio_claim_host — no cap, it's actually the moment where one single SDIO function gets to say "this bus is MINE" and nobody else can touch it. main character energy fr fr 👑

✨ NAME ✨

sdio_claim_host — exclusively claim a bus for a certain SDIO function 🎀

🌸 SYNOPSIS 🌸

void sdio_claim_host (struct sdio_func *func );

🦋 ARGUMENTS 🦋

• func — the SDIO function that will be accessed. like, the one doing the accessing. that's your girl 💅

⭐ DESCRIPTION ⭐

So here's the vibe: you call this to claim a bus for a set of operations. 🫶

The SDIO function you hand in is literally just there so the kernel can figure out which bus is the relevant one — you don't gotta point at the bus yourself, the function does the pointing for you. iykyk ✨

🔥 SEE ALSO 🔥

• Kernel file ./drivers/mmc/core/sdio_io.c — that's where all this lives, go read it bestie 📖
• sdio_release_host(9) — the one you must pair this with, the "okay i'm done, it's yours again" 💀
• 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_hold_now(9)
• sdio_retune_release(9)

and that's the whole page, bestie 🌈

this lil fairy tale lives in ./drivers/mmc/core, stamped October 2026, and it's sdio_claim_host(9) all the way down 🧚💜 slay, go claim your bus (and remember to release it 🙈).