Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752143AbaB1Ule (ORCPT ); Fri, 28 Feb 2014 15:41:34 -0500 Received: from mail-vc0-f172.google.com ([209.85.220.172]:44249 "EHLO mail-vc0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752028AbaB1Ulc (ORCPT ); Fri, 28 Feb 2014 15:41:32 -0500 MIME-Version: 1.0 In-Reply-To: <20140228203200.GE3405@xanatos> References: <1393259343-825-1-git-send-email-mathias.nyman@linux.intel.com> <20140228203200.GE3405@xanatos> Date: Fri, 28 Feb 2014 12:41:31 -0800 Message-ID: Subject: Re: [RFC PATCH v2] xhci: Prevent runtime pm from autosuspending during initialization From: Dan Williams To: Sarah Sharp Cc: Alan Stern , Mathias Nyman , USB list , david.a.cohen@linux.intel.com, Jianqiang Tang , "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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. -- 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/