pci_acpi_cle..._lookup_hook(9)

💅 pci_acpi_clear_companion_lookup_hook — like, the kernel API manual edition 🎀

okay so bestie, welcome to the pci_acpi_clear_companion_lookup_hook(9) page, straight out of the Kernel API Manual. yes that's a whole mouthful, we're getting through it together 🫶

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✨ NAME ✨

pci_acpi_clear_companion_lookup_hook — clears the ACPI companion lookup callback. that's it, that's the vibe 💅

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🦋 SYNOPSIS 🦋

void pci_acpi_clear_companion_lookup_hook (void );

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🌸 ARGUMENTS 🌸

• void — no arguments. literally none. nothing to pass, nothing to panic about 😌 zero things, iconic behaviour.

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🔥 DESCRIPTION 🔥

so what does it actually do? it clears the special ACPI companion lookup callback that was, at some point, set by pci_acpi_set_companion_lookup_hook 👀 like, it's the undo button for that hook, no cap.

and here's the part you gotta respect: it blocks until the last running instance of the callback returns, and then it clears it. so it's not out here yanking the callback out from under somebody mid-run — it waits, patiently, main character energy but polite 🧚

⚠️ the caller is responsible for the appropriate ordering of the invocations of this function with respect to the enumeration of the PCI devices needing the callback cleared by it. no pressure bestie, but that ordering? that's on you, fr fr. don't come for this function when the sequencing was your idea 💀

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👑 SEE ALSO 👑

• Kernel file: ./drivers/pci/pci-acpi.c
• pciehp_is_native(9)
• shpchp_is_native(9)
• pci_acpi_wake_bus(9)
• pci_acpi_wake_dev(9)
• pci_acpi_add_root_pm_notifier(9)
• pci_acpi_add_pm_notifier(9)
• pci_dev_acpi_reset(9)
• pci_acpi_set_companion_lookup_hook(9)
• pci_acpi_optimize_delay(9)
• pci_msi_register_fwnode_provider(9)
• pci_host_bridge_acpi_msi_domain(9)

like, read the whole little family, they're all connected, iykyk 🌈

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anyway, that's the page! 🎀 this one comes to you from the source path ./drivers/pci, dated October 2026 — so yeah, she's from the future, slay ✨💜