On Monday 19 January 2015 11:12:50 Yijing Wang wrote: > On 2015/1/16 17:18, Arnd Bergmann wrote: > > On Friday 16 January 2015 09:44:08 Yijing Wang wrote: > >> @@ -2066,11 +2064,11 @@ struct pci_bus *pci_scan_root_bus(struct device *parent, u32 db, > >> { > >> struct pci_host_bridge *host; > >> > >> - host = pci_create_host_bridge(parent, db, resources); > >> + host = pci_create_host_bridge(parent, db, resources, sysdata); > >> if (!host) > >> return NULL; > >> > >> - return __pci_scan_root_bus(host, ops, sysdata); > >> + return __pci_scan_root_bus(host, ops); > >> } > >> EXPORT_SYMBOL(pci_scan_root_bus); > >> > > > > How about keeping the sysdata out of the pci_create_host_bridge interface, and > > refactoring it so that the call sequence becomes > > > > host = pci_create_host_bridge(parent, db, resources); > > host->sysdata = sysdata; > > __pci_scan_root_bus(host, ops); > > > > This way, we can make sysdata completely option. I assume that more of the > > fields we have in sysdata today can get moved into pci_host_bridge > > over time, so a host bridge driver can just assign those members individually > > between pci_create_host_bridge and __pci_scan_root_bus. > > I put the sysdata in pci_host_bridge, because some platforms x86/ia64 > need to call pcibios_root_bridge_prepare() before pci_host_bridge registration > in pci_create_host_bridge(), and pcibios_root_bridge_prepare() need the companion > acpi device pointer which is stored in sysdata. > > I like you idea, but I haven't find a better way yet. Ok, fair enough. We can always try to find ways for getting rid of pcibios_root_bridge_prepare() later, though I suspect as soon as we have the callback, it will get used for other things as well ;-) Arnd -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html