Re: [PATCH] usb: dwc3: remove 'pm_runtime_set_active' in resume callback

taehyun cho
2021-03-17T08:25:22Z

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On Mon, Mar 15, 2021 at 10:13:35AM -0400, Alan Stern wrote:
> On Mon, Mar 15, 2021 at 04:43:17PM +0900, taehyun cho wrote:
> > 'pm_runtime_set_active' sets a flag to describe rumtime status.
> > This flag is automatically set in pm_runtime_get_sync/put_sync API.
> > 'pm_runtime_set_active' checks the runtime status of parent device.
> > As a result, the below error message is printed.
> > dwc3 11110000.dwc3: runtime PM trying to activate child device
> > 11110000.dwc3 but parent (11110000.usb) is not active.
>
> This is very suspicious. That error message indicates a real error is
> present; removing these pm_runtime_set_active calls won't fix the error.
>
> You need to determine why the parent platform device 11110000.usb isn't
> active when the dwc3 probe and resume routines are called. It seems
> likely that there is a bug in the platform device's driver.
>
> Alan Stern
>

Alan,

Thanks to your comments, I checked our platform device driver and found
the problem. Our parent platform device didn't set active in resume
callback. This made a problem. Thank you for the help and sorry for
disturbing you.

Taehyun Cho

> > Signed-off-by: taehyun cho <taehyun.cho@samsung.com>
> > ---
> > drivers/usb/dwc3/core.c | 2 --
> > 1 file changed, 2 deletions(-)
> >
> > diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> > index 94fdbe502ce9..e7c0e390f885 100644
> > --- a/drivers/usb/dwc3/core.c
> > +++ b/drivers/usb/dwc3/core.c
> > @@ -1553,7 +1553,6 @@ static int dwc3_probe(struct platform_device *pdev)
> >
> > spin_lock_init(&dwc->lock);
> >
> > - pm_runtime_set_active(dev);
> > pm_runtime_use_autosuspend(dev);
> > pm_runtime_set_autosuspend_delay(dev, DWC3_DEFAULT_AUTOSUSPEND_DELAY);
> > pm_runtime_enable(dev);
> > @@ -1920,7 +1919,6 @@ static int dwc3_resume(struct device *dev)
> > return ret;
> >
> > pm_runtime_disable(dev);
> > - pm_runtime_set_active(dev);
> > pm_runtime_enable(dev);
> >
> > return 0;
> > --
> > 2.26.0