On Tue, Dec 04, 2018 at 09:40:49PM +0100, Lukas Wunner wrote: > > I wonder if our pci_bridge_d3_possible() heuristics would need to be > > refined somehow? At least if this blacklist starts growing. > > We do blacklist such non-native hotplug ports, but of course only if > the Hot-Plug Capable bit is set: > > /* > * Hotplug ports handled by firmware in System Management Mode > * may not be put into D3 by the OS (Thunderbolt on non-Macs). > */ > if (bridge->is_hotplug_bridge && !pciehp_is_native(bridge)) > return false; > > I guess your question boils down to, is there any better way to recognize > ports which are handled by the platform firmware? Exactly :) Gigabyte makes lots of motherboards and many of them have USB-C ports so it may be that they use the same BIOS accross them. > Does acpiphp bind to this port? It does, yes but AFAIK it binds to any PCI bus (bridge) if it has an ACPI companion.