pci_is_thunderbolt_attached(9)

💖 pci_is_thunderbolt_attached — the Kernel API Manual ✨

okay so bestie, gather round, because we're about to find out whether your PCI device is living its little life on a Thunderbolt daisy chain or whether it's literally soldered to the motherboard with no escape. 🦋 this one's a bool-returning king and honestly it ate. 💅

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🌸 SYNOPSIS 🌸

bool pci_is_thunderbolt_attached (struct pci_dev *pdev );

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🎀 ARGUMENTS 🎀

• pdev — the PCI device we're vibe-checking. that's it, that's the whole input. 🫶

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✨ DESCRIPTION ✨

so the way this works is iconic: it walks upwards from pdev and checks, for each bridge it encounters, whether that bridge is part of a Thunderbolt controller. 🌈

and if it reaches the host bridge? that means pdev is not Thunderbolt-attached. nope, not even a little. and tbh it's probably just soldered straight to the mainboard — like, permanently. no cap. 😭

lowkey the important thing to remember: reaching the host bridge is the "nope, not Thunderbolt" signal, and it usually means the device is physically stuck to the motherboard. 💀

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👑 SEE ALSO 👑

• Kernel file ./include/linux/pci.h
• enum pci_interrupt_pin(9)
• pci_channel_state_t(9)
• pci_is_bridge(9)
• pci_is_vga(9)
• pci_is_display(9)
• struct pci_driver(9)
• PCI_DEVICE(9)
• PCI_DEVICE_DRIVER_OVERRIDE(9)
• PCI_DRIVER_OVERRIDE_DEVICE_VFIO(9)
• PCI_DEVICE_SUB(9)
• PCI_DEVICE_CLASS(9)
• PCI_VDEVICE(9)
• PCI_VDEVICE_SUB(9)
• PCI_DEVICE_DATA(9)
• pcie_capability_clear_and_set_word(9)
• pci_bus_for_each_resource(9)
• module_pci_driver(9)
• builtin_pci_driver(9)
• pci_irq_type(9)
• pci_irqd_intx_xlate(9)
• pci_resource_is_io(9)
• pci_resource_is_mem(9)
• pci_pcie_cap(9)
• pci_is_pcie(9)
• pcie_caps_reg(9)
• pci_pcie_type(9)
• pcie_find_root_port(9)
• pci_vpd_alloc(9)
• pci_vpd_find_id_string(9)
• pci_vpd_find_ro_info_keyword(9)
• pci_vpd_check_csum(9)
• pci_ari_enabled(9)

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that's the whole page, bestie — go forth and check those bridges 💖

and before you close the tab: this little icon lives in ./include/linux, dated October 2026, and it's the pci_is_thunderbolt_attached(9) page. slay. 🎀✨