On Thu, 2 Aug 2012, Lan Tianyu wrote: > A summary about what we should do now after such long discussion. If I > lost something or miss something, please correct me. > > 1) Add "auto" option to each port's power policy sysfs attribute. When > set to "auto", those ports which have never been attached with devices > will be power off immediately.
No. Ports will be powered down only if it's impossible to attach a device, that is, if PortIsConnectable is clear. As a safety check, you should also verify that no device is currently attached. > 2)Expose the ACPI PortIsConnectable, UserVisible (If it was on the ACPI > platfrom) and usb DeviceRemovable flag via sysfs attributes. > > 3)Root-hub set port's DeviceRemovable flag where PortIsConnectable and > UserVisible are clear. Set DeviceRemovable whenever UserVisible is set. Right now ehci-hcd and uhci-hcd always set DeviceRemovable to 0. > 4)Add QUIRK_POWEROFF_MORPHS flags for those devices which retain > important settings across a reset but lose them when power is removed. This flag doesn't care about resets. It applies to any device which loses important settings when bus power is removed. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
