RE: [PATCH] usb:solve resume usb device identification problem

From: Lipengcheng
Date: Mon Jul 11 2016 - 21:50:15 EST


Hi,

> -----Original Message-----
> From: Lu Baolu [mailto:baolu.lu@xxxxxxxxxxxxxxx]
> Sent: Tuesday, July 12, 2016 8:42 AM
> To: Lipengcheng; gregkh@xxxxxxxxxxxxxxxxxxx; stern@xxxxxxxxxxxxxxxxxxx; chasemetzger15@xxxxxxxxx; mathias.nyman@xxxxxxxxxxxxxxx;
> oneukum@xxxxxxxx; jun.li@xxxxxxxxxxxxx
> Cc: linux-usb@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH] usb:solve resume usb device identification problem
>
> Hi,
>
> On 07/11/2016 08:57 PM, Pengcheng Li wrote:
> > A usb device in the connection state. Then host is suspend and resume.
> > But the usb device could not be at the right speed. We should be reset
> > the reset.
>
> Have you tried applying XHCI_RESET_ON_RESUME quirk to your host controller driver? Is your usb device self powered?
>
I do not apply XHCI_RESET_ON_RESUME quir to my host controller driver. I select no pci platform. Our usb device is not self powered.
> Best regards,
> Lu Baolu
>
> >
> > Signed-off-by: Pengcheng Li <lpc.li@xxxxxxxxxxxxx>
> > ---
> > drivers/usb/core/hub.c | 6 +++++-
> > 1 file changed, 5 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index
> > bee1351..cd71bb3 100644
> > --- a/drivers/usb/core/hub.c
> > +++ b/drivers/usb/core/hub.c
> > @@ -3455,7 +3455,7 @@ int usb_port_resume(struct usb_device *udev, pm_message_t msg)
> > struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
> > struct usb_port *port_dev = hub->ports[udev->portnum - 1];
> > int port1 = udev->portnum;
> > - int status;
> > + int status, retval;
> > u16 portchange, portstatus;
> >
> > if (!test_and_set_bit(port1, hub->child_usage_bits)) { @@ -3512,6
> > +3512,10 @@ int usb_port_resume(struct usb_device *udev, pm_message_t msg)
> > }
> > }
> >
> > + retval = hub_port_reset(hub, port1, udev, HUB_ROOT_RESET_TIME, false);
> > + if (retval < 0)
> > + hub_port_disable(hub, port1, 0);
> > +
> > if (udev->persist_enabled)
> > status = wait_for_connected(udev, hub, &port1, &portchange,
> > &portstatus);
Best regards
Pengcheng Li