Re: [PATCH 6/6] USB / PM: Allow USB devices to remain runtime-suspended when sleeping

From: Alan Stern
Date: Wed Apr 01 2015 - 10:01:39 EST


On Wed, 1 Apr 2015, Oliver Neukum wrote:

> On Tue, 2015-03-31 at 13:09 -0400, Alan Stern wrote:
> > In other words, if the device is currently in runtime suspend with
> > remote wakeup enabled, but device_may_wakeup() returns 0 (so that the
> > device should be disabled for wakeup when the system goes into
> > suspend), then the prepare callback has to return 0.
> >
> > Therefore what you need to do here is something like this:
> >
> > struct usb_device *udev = to_usb_device(dev);
> >
> > /* Return 0 if the current wakeup setting is wrong, otherwise
> > 1 */
>
> And the other way round?

Your meaning isn't clear. Are you asking what should happen if the
device is in runtime suspend with remote wakeup disabled, but
device_may_wakeup() returns 1? That case should never happen -- but
if it does then the prepare callback should return 0.

Alan Stern

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