On Thu, Sep 11, 2025 at 3:57 PM ryan zhou <ryanzhou54@xxxxxxxxx> wrote: > > Rafael J. Wysocki <rafael@xxxxxxxxxx> 于2025年9月11日周四 19:36写道： > > > > On Thu, Sep 11, 2025 at 12:58 PM Xu Yang <xu.yang_2@xxxxxxx> wrote: > > > > > > Hi Ryan, > > > > > > On Thu, Sep 11, 2025 at 01:32:47AM +0000, Thinh Nguyen wrote: > > > > On Wed, Sep 10, 2025, Ryan Zhou wrote: > > > > > Issue description:During the wake-up sequence, if the system invokes > > > > > dwc3->resume and detects that the parent device of dwc3 is in a > > > > > runtime suspend state, the system will generate an error: runtime PM > > > > > trying to activate child device xxx.dwc3 but parent is not active. > > > > > > > > > > Solution:At the dwc3->resume entry point, if the dwc3 controller > > > > > is detected in a suspended state, the function shall return > > > > > immediately without executing any further operations. > > > > > > > > > > Signed-off-by: Ryan Zhou <ryanzhou54@xxxxxxxxx> > > > > > --- > > > > > drivers/usb/dwc3/core.c | 3 +++ > > > > > 1 file changed, 3 insertions(+) > > > > > > > > > > diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c > > > > > index 370fc524a468..06a6f8a67129 100644 > > > > > --- a/drivers/usb/dwc3/core.c > > > > > +++ b/drivers/usb/dwc3/core.c > > > > > @@ -2687,6 +2687,9 @@ int dwc3_pm_resume(struct dwc3 *dwc) > > > > > struct device *dev = dwc->dev; > > > > > int ret = 0; > > > > > > > > > > + if (pm_runtime_suspended(dev)) > > > > > + return ret; > > > > > + > > > > > > > > Is this a documented behavior where the device should remain runtime > > > > suspend on system resume? I feel that that this should be configurable > > > > by the user or defined the PM core. I don't think we should change > > > > default behavior here just to workaround the issue that we're facing. > > > > > > > > What if the user wants to keep the old behavior and resume up the device > > > > on system resume? > > > > > > What about resume the device firstly if it's already runtime suspended when > > > call dwc3_pm_suspend(). Therefor, the old behavior can be kept and the issue > > > can be avoided. > > > > > > diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c > > > index 370fc524a468..1b8dbb260017 100644 > > > --- a/drivers/usb/dwc3/core.c > > > +++ b/drivers/usb/dwc3/core.c > > > @@ -2672,6 +2672,9 @@ int dwc3_pm_suspend(struct dwc3 *dwc) > > > struct device *dev = dwc->dev; > > > int ret; > > > > > > + if (pm_runtime_suspended(dev)) > > > + pm_runtime_resume(dev); > > > > You can just call pm_runtime_resume() here without the preliminary check. > > If the device is active before sleep, skip runtime_resume after wakeup > and just call dwc3->suspend. But pm_runtime_resume() will not resume an active device, will it?
