Hi Oliver, thanks for the review!
On Tue, 2019-03-19 at 12:01 +0100, Oliver Neukum wrote:
> On Mo, 2019-03-18 at 18:00 +0100, Nicolas Saenz Julienne wrote:
> > This patch clears "port_remote_wakeup" upon detecting a device
> > disconnection. Making sure the above mentioned situation doesn't trigger
> > a PM busyloop.
>
> Hi,
>
> that is an interesting race condition.
>
> > Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@xxxxxxx>
> > ---
> > drivers/usb/host/xhci-hub.c | 3 +++
> > 1 file changed, 3 insertions(+)
> >
> > diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c
> > index e2eece693655..bea853f45aec 100644
> > --- a/drivers/usb/host/xhci-hub.c
> > +++ b/drivers/usb/host/xhci-hub.c
> > @@ -942,6 +942,9 @@ static void xhci_get_usb3_port_status(struct xhci_port
> > *port, u32 *status,
> > bus_state->suspended_ports &= ~(1 << portnum);
> > }
> >
> > + if (!(portsc & PORT_CONNECT))
> > + bus_state->port_remote_wakeup &= ~(1 << portnum);
> > +
> > xhci_hub_report_usb3_link_state(xhci, status, portsc);
> > xhci_del_comp_mod_timer(xhci, portsc, portnum);
> > }
>
> Why are you putting that logic into xhci_get_usb3_port_status()?
> It looks to me like there is already something related in the caller
>
> /* USB2 and USB3 specific bits, including Port Link State */
> if (hcd->speed >= HCD_USB3)
> xhci_get_usb3_port_status(port, &status, raw_port_status);
> else
> xhci_get_usb2_port_status(port, &status, raw_port_status,
> flags);
> /*
> * Clear stale usb2 resume signalling variables in case port changed
> * state during resume signalling. For example on error
> */
> if ((bus_state->resume_done[wIndex] ||
> test_bit(wIndex, &bus_state->resuming_ports)) &&
> (raw_port_status & PORT_PLS_MASK) != XDEV_U3 &&
> (raw_port_status & PORT_PLS_MASK) != XDEV_RESUME) {
> bus_state->resume_done[wIndex] = 0;
> clear_bit(wIndex, &bus_state->resuming_ports);
> usb_hcd_end_port_resume(&hcd->self, wIndex);
> }
You're right, xhci_get_usb3_port_status() is not the ideal spot I'll move the
code there.
>
> Otherwise very good catch!
>
> Regards
> Oliver
>
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