Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752727AbaB1V4F (ORCPT ); Fri, 28 Feb 2014 16:56:05 -0500 Received: from out3-smtp.messagingengine.com ([66.111.4.27]:44893 "EHLO out3-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752115AbaB1V4C (ORCPT ); Fri, 28 Feb 2014 16:56:02 -0500 X-Sasl-enc: LCGF+zZkLHAa6bHHhaRrexBFn0sEbH5TROU6HGpcAV9o 1393624561 Date: Fri, 28 Feb 2014 13:57:39 -0800 From: Greg KH To: Dan Williams Cc: Sarah Sharp , Alan Stern , Mathias Nyman , USB list , david.a.cohen@linux.intel.com, Jianqiang Tang , "linux-kernel@vger.kernel.org" Subject: Re: [RFC PATCH v2] xhci: Prevent runtime pm from autosuspending during initialization Message-ID: <20140228215739.GA14992@kroah.com> References: <1393259343-825-1-git-send-email-mathias.nyman@linux.intel.com> <20140228203200.GE3405@xanatos> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.22 (2013-10-16) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Feb 28, 2014 at 12:41:31PM -0800, Dan Williams wrote: > On Fri, Feb 28, 2014 at 12:32 PM, Sarah Sharp > wrote: > > On Mon, Feb 24, 2014 at 12:44:46PM -0500, Alan Stern wrote: > >> On Mon, 24 Feb 2014, Mathias Nyman wrote: > >> > >> > xHCI driver has its own pci probe function that will call usb_hcd_pci_probe > >> > to register its usb-2 bus, and then continue to manually register the > >> > usb-3 bus. usb_hcd_pci_probe does a pm_runtime_put_noidle at the end and > >> > might thus trigger a runtime suspend before the usb-3 bus is ready. > >> > > >> > Prevent the runtime suspend by increasing the usage count in the > >> > beginning of xhci_pci_probe, and decrease it once the usb-3 bus is > >> > ready. > >> > > >> > xhci-platform driver is not using usb_hcd_pci_probe to set up > >> > busses and should not need to have it's usage count increased during probe. > >> > > >> > Signed-off-by: Mathias Nyman > >> > --- > >> > drivers/usb/host/xhci-pci.c | 11 ++++++++++- > >> > 1 file changed, 10 insertions(+), 1 deletion(-) > >> > > >> > diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c > >> > index 04f986d..ea7158b 100644 > >> > --- a/drivers/usb/host/xhci-pci.c > >> > +++ b/drivers/usb/host/xhci-pci.c > >> > @@ -190,6 +190,10 @@ static int xhci_pci_probe(struct pci_dev *dev, const struct pci_device_id *id) > >> > struct usb_hcd *hcd; > >> > > >> > driver = (struct hc_driver *)id->driver_data; > >> > + > >> > + /* Prevent USB-2 roothub runtime suspend until USB-3 is initialized. */ > >> > + pm_runtime_get_noresume(&dev->dev); > >> > >> Strictly speaking, this prevents the _controller_ from going into > >> runtime suspend -- not the root hub. > > > > Signed-off-by: Sarah Sharp > > Pardon the nitpick, but this is an acked-by if Mathias is submitting. No, it's a "chain of signed-off-by's" and this is allowed just fine (it used to be the default-thing before we came up with the "acked-by" line...) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/