On Thu, Jul 16, 2009 at 01:12:28AM +0000, James Bottomley wrote: > On Thu, 2009-07-16 at 00:43 +0100, Matthew Garrett wrote: > > Userspace may wish to make policy decisions based on whether a host > > supports device hotplug or not - for example, AHCI link power management > > disables hotplug, so may only be desirable on hotplug ports. Add > > support for marking hosts as hotpluggable in order to allow userspace to > > treat them appropriately. > > OK, so I don't really understand what the hotplug flag means. > > You seem to be setting it unconditionally on most sata HBAs. If it just > means "bus is hotpluggable", it should be set to 1 at initialisation and > the few non hot plug busses (like SPI) get to reset it. It's a tossup. PATA's not hotpluggable (in the general case), so I just picked a default and went with it. Inverting it would be easy enough, I guess. > However, by definition SATA (like SAS) is a hotplug bus ... why isn't it > set for some SATA controllers ... is it because the HBA itself does > something wrong when a hotplug event comes in? Some older controllers don't provide direct access to the phy registers, so there's no way to interpret hotplug events correctly. -- Matthew Garrett | mjg59@xxxxxxxxxxxxx -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
