On Thu, 7 May 2015, Lu, Baolu wrote: > >> + void (*device_suspend)(struct usb_hcd *, struct usb_device *udev, > >> + pm_message_t msg); > >> + void (*device_resume)(struct usb_hcd *, struct usb_device *udev, > >> + pm_message_t msg); > >> }; > > Your callbacks don't use the msg argument. What makes you think it is > > needed? > > This msg argument is valuable. XHCI spec defines a capability named FSC > (Force Save context Capability). When this capability is implemented, the > Save State operation (do during host suspend) shall save any cached Slot, > Endpoint, Stream or other Context information to memory. xHCI hcd could > use this "msg" to determine whether it needs to issue stop endpoint with > SP (suspend) bit set.
I don't understand. What is the advantage of using FSC? How would xhci-hcd use "msg" to determine this? And why doesn't your 2/3 patch already do it? Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
