On Fri, 13 Dec 2013, Dan Williams wrote: > > I'm actually leaning towards enabling the check for warm reset broadly. > > It seems like it wouldn't hurt to issue a warm reset on the USB 3.0 > > ports if they're in compliance, poll, or rx.detect. So, let's enable > > this broadly in xhci_resume, mark the patch for stable, but ask for the > > backport to be delayed until 3.13.3 is out, to allow for more testing. > > If anyone complains of xHCI behavior changes, we'll change the code to > > add a quirk. > > Is there a clean way to make this per-port rather than globally at > xhci_resume()? I am looking to hook into this for port power recovery > as Tianyu's testing encountered "warm reset required" conditions at > runtime_resume. I'm still on the hunt for a solid reproducer, but it > indicates this is a more general quirk with power session recovery. There's no reason you can't do per-port testing inside xhci_resume (assuming you know what to test for) as well as putting a warm reset in the port-power handler of xhci_hub_control. Of course, doing simultaneous warm resets on multiple ports will use less time than resetting each port individually, in sequence. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
