Hi Greg,
> > >
> > > How do you know that the disconnect will not have already been
> > > triggered at this point, when the status changes?
> >
> > The status change of connection is before port reset.
> > In this stage, the device is not port enable, and it will not trigger
> disconnection.
>
> Ok, then say that here please :)
Okay. I will add it.
> > > > diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index
> > > > a739403a9e45..8433ff89dea6 100644
> > > > --- a/drivers/usb/core/hub.c
> > > > +++ b/drivers/usb/core/hub.c
> > > > @@ -614,6 +614,19 @@ static int hub_ext_port_status(struct usb_hub
> > > > *hub,
> > > int port1, int type,
> > > > ret = 0;
> > > > }
> > > > mutex_unlock(&hub->status_mutex);
> > > > +
> > > > + if (!ret) {
> > > > + struct usb_device *hdev = hub->hdev;
> > > > +
> > > > + if (hdev && !hdev->parent) {
> > >
> > > Why the check for no parent? Please document that here in a comment.
> >
> > I will add a comment :
> > /* Only notify roothub. That is, when hdev->parent is empty. */
>
> Also document this that this will only happen for root hub status changes, that's
> not obvious in the callback name or documentation or anywhere else here.
All usb phy notifications (connection, disconnection) are only for roothub.
So I don't special to doc this.
> > > > + struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
> > > > +
> > > > + if (hcd->usb_phy)
> > > > +
> > > usb_phy_notify_port_status(hcd->usb_phy,
> > > > +
> port1 -
> > > 1, *status, *change);
> > > > + }
> > > > + }
> > > > +
> > >
> > > This is safe to notify with the hub mutex unlocked? Again, a
> > > comment would be helpful to future people explaining why that is so.
> > >
> >
> > I will add a comment:
> > /*
> > * There is no need to lock status_mutex here, because status_mutex
> > * protects hub->status, and the phy driver only checks the port
> > * status without changing the status.
> > */
>
> Looks good, if you do it without the trailing whitespace :)
>
Okay
Thanks,
Stanley
