Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755241AbcLNJ1B (ORCPT ); Wed, 14 Dec 2016 04:27:01 -0500 Received: from mail-oi0-f51.google.com ([209.85.218.51]:34852 "EHLO mail-oi0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754877AbcLNJ07 (ORCPT ); Wed, 14 Dec 2016 04:26:59 -0500 MIME-Version: 1.0 In-Reply-To: References: <20161201214604.20717-1-robert.foss@collabora.com> <20161201214604.20717-2-robert.foss@collabora.com> From: Baolin Wang Date: Wed, 14 Dec 2016 17:26:58 +0800 Message-ID: Subject: Re: [PATCH v7 1/2] usb: xhci: plat: Enable runtime PM To: Robert Foss Cc: mathias.nyman@intel.com, Greg KH , Julius Werner , Andrew Bresticker , Felipe Balbi , Brian Norris , LKML Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3539 Lines: 126 Hi Robert, On 14 December 2016 at 14:43, Robert Foss wrote: > Hey Baolin, > > On 2016-12-12 12:21 AM, Baolin Wang wrote: >> >> Hi Robert, >> >> On 2 December 2016 at 05:46, Robert Foss >> wrote: >>> >>> Enable runtime PM for the xhci-plat device so that the parent device >>> may implement runtime PM. >>> >>> Signed-off-by: Robert Foss >>> >>> Tested-by: Robert Foss >>> --- >>> drivers/usb/host/xhci-plat.c | 29 +++++++++++++++++++++++++++-- >>> 1 file changed, 27 insertions(+), 2 deletions(-) >>> >>> diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c >>> index ed56bf9ed885..ba4efe74f537 100644 >>> --- a/drivers/usb/host/xhci-plat.c >>> +++ b/drivers/usb/host/xhci-plat.c >>> @@ -246,6 +246,9 @@ static int xhci_plat_probe(struct platform_device >>> *pdev) >>> if (ret) >>> goto dealloc_usb2_hcd; >>> >>> + pm_runtime_set_active(&pdev->dev); >>> + pm_runtime_enable(&pdev->dev); >> >> >> You did not implement the runtime callbacks of xHCI device, then how >> can the parent device control the resume/suspend of xHCI device by >> runtime PM mechanism? Could you see my previous patch which implement >> the runtime callbacks for xHCI device? >> https://lkml.org/lkml/2016/11/28/25 >> > > Pardon my ignorance, but which exact functions need to be implemented? > Also, does the lkml link you provided contain an example implementation of > those functions? Please check below link: https://lkml.org/lkml/2016/12/13/32 https://lkml.org/lkml/2016/12/13/34 > > >>> + >>> return 0; >>> >>> >>> @@ -274,6 +277,8 @@ static int xhci_plat_remove(struct platform_device >>> *dev) >>> struct xhci_hcd *xhci = hcd_to_xhci(hcd); >>> struct clk *clk = xhci->clk; >>> >>> + pm_runtime_disable(&dev->dev); >>> + >>> usb_remove_hcd(xhci->shared_hcd); >>> usb_phy_shutdown(hcd->usb_phy); >>> >>> @@ -292,6 +297,13 @@ static int xhci_plat_suspend(struct device *dev) >>> { >>> struct usb_hcd *hcd = dev_get_drvdata(dev); >>> struct xhci_hcd *xhci = hcd_to_xhci(hcd); >>> + int ret; >>> + >>> + ret = pm_runtime_get_sync(dev); >>> + if (ret < 0) { >>> + pm_runtime_put(dev); >>> + return ret; >>> + } >>> >>> /* >>> * xhci_suspend() needs `do_wakeup` to know whether host is >>> allowed >>> @@ -301,15 +313,28 @@ static int xhci_plat_suspend(struct device *dev) >>> * reconsider this when xhci_plat_suspend enlarges its scope, >>> e.g., >>> * also applies to runtime suspend. >>> */ >>> - return xhci_suspend(xhci, device_may_wakeup(dev)); >>> + ret = xhci_suspend(xhci, device_may_wakeup(dev)); >>> + pm_runtime_put(dev); >>> + >>> + return ret; >>> } >>> >>> static int xhci_plat_resume(struct device *dev) >>> { >>> struct usb_hcd *hcd = dev_get_drvdata(dev); >>> struct xhci_hcd *xhci = hcd_to_xhci(hcd); >>> + int ret; >>> >>> - return xhci_resume(xhci, 0); >>> + ret = pm_runtime_get_sync(dev); >>> + if (ret < 0) { >>> + pm_runtime_put(dev); >>> + return ret; >>> + } >>> + >>> + ret = xhci_resume(xhci, 0); >>> + pm_runtime_put(dev); >>> + >>> + return ret; >>> } >>> >>> static const struct dev_pm_ops xhci_plat_pm_ops = { >>> -- >>> 2.11.0 >>> >> >> >> > -- Baolin.wang Best Regards