Hi Robert, On 14 December 2016 at 14:43, Robert Foss <robert.f...@collabora.com> wrote: > Hey Baolin, > > On 2016-12-12 12:21 AM, Baolin Wang wrote: >> >> Hi Robert, >> >> On 2 December 2016 at 05:46, Robert Foss <robert.f...@collabora.com> >> wrote: >>> >>> Enable runtime PM for the xhci-plat device so that the parent device >>> may implement runtime PM. >>> >>> Signed-off-by: Robert Foss <robert.f...@collabora.com> >>> >>> Tested-by: Robert Foss <robert.f...@collabora.com> >>> --- >>> 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