ich_set_dmamode(9)

✨ NAME ✨

ich_set_dmamode — initialize host controller PATA DMA timings 💅

(also hi, this page lives in the Kernel API Manual 🫶)

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🌸 SYNOPSIS 🌸

void ich_set_dmamode (struct ata_port *ap , struct ata_device *adev );

ok so it returns nothing (void, iconic, no notes) and it takes these two:

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🎀 ARGUMENTS 🎀

• ap — the port whose timings we're configuring. like, this is the port we're doing a little makeover on 💖
• adev — um

ngl bestie the original manpage literally just says um for adev 😭 i'm not making that up and i'm not gonna invent a meaning for it either. that's what it says. um. we respect the source text in this house 🫡

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🦋 DESCRIPTION 🦋

It sets the MW/UDMA mode for the device — and it does that in the host controller PCI config space ✨ so yes, it's poking the actual hardware config registers, main character energy fr fr.

LOCKING: None (inherited from caller).

🚨 read that again: locking is inherited from the caller. this function does zero locking of its own, so whatever lock situation you had going in is the one you've got. it is not out here protecting you. you gotta bring your own. no cap 💀

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🔥 SEE ALSO 🔥

Kernel file ./drivers/ata/ata_piix.c, plus these besties who are all in the same friend group:

• ich_pata_cable_detect(9)
• piix_pata_prereset(9)
• piix_set_piomode(9)
• do_pata_set_dmamode(9)
• piix_set_dmamode(9)
• piix_check_450nx_errata(9)
• piix_init_one(9)

iykyk — that's the whole ata_piix squad 🧚

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ok that's the page!! huge shoutout to the source ./drivers/ata and this whole thing is dated October 2026 — ich_set_dmamode(9), that's a wrap, slay, periodt 💜🎀🦋