2021-03-15 07:44:55

by taehyun cho

[permalink] [raw]
Subject: [PATCH] usb: dwc3: remove 'pm_runtime_set_active' in resume callback

'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.

Signed-off-by: taehyun cho <[email protected]>
---
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


2021-03-15 14:50:24

by Alan Stern

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

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

> Signed-off-by: taehyun cho <[email protected]>
> ---
> 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

2021-03-17 15:50:09

by Alan Stern

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

On Wed, Mar 17, 2021 at 05:25:20PM +0900, taehyun cho wrote:
> 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.

Ah, good. Does the platform driver set the active flag in its probe
routine?

> Thank you for the help and sorry for
> disturbing you.

No problem at all.

Alan Stern