Re: [Qemu-devel] [PATCH 1/3] usb-hub: wakeup on attach

[hkran <hkran@linux.vnet.ibm.com>]

On 11/01/2011 10:56 PM, Gerd Hoffmann wrote:
> When attaching a new device we must send a wakeup request to the root
> hub, otherwise the guest will not notice the new device in case the
> usb hub is suspended.
>
> Signed-off-by: Gerd Hoffmann<kraxel@redhat.com>
> ---
>   hw/usb-hub.c |    1 +
>   1 files changed, 1 insertions(+), 0 deletions(-)
>
> diff --git a/hw/usb-hub.c b/hw/usb-hub.c
> index 09c6516..7b47079 100644
> --- a/hw/usb-hub.c
> +++ b/hw/usb-hub.c
> @@ -163,6 +163,7 @@ static void usb_hub_attach(USBPort *port1)
>       } else {
>           port->wPortStatus&= ~PORT_STAT_LOW_SPEED;
>       }
> +    usb_wakeup(&s->dev);
>   }
>
>   static void usb_hub_detach(USBPort *port1)
It seems "attach" works. But the "detach" did not work.
I added over two usbdevice "tablet" and usb_del them. I found sometimes 
the guest did not know that the tablet had been deleted in host when the 
port
's status changed to "suspend".

After I add usb_wake like this in the function usb_hub_detach. the 
problem can be fixed.

static void usb_hub_detach(USBPort *port1)
{
     USBHubState *s = port1->opaque;
     USBHubPort *port = &s->ports[port1->index];

     usb_wakeup(&s->dev);                 
---------------------------------->wakeup when detach
     /* Let upstream know the device on this port is gone */
     s->dev.port->ops->child_detach(s->dev.port, port1->dev);

     port->wPortStatus &= ~PORT_STAT_CONNECTION;
     port->wPortChange |= PORT_STAT_C_CONNECTION;
     if (port->wPortStatus & PORT_STAT_ENABLE) {
         port->wPortStatus &= ~PORT_STAT_ENABLE;
         port->wPortChange |= PORT_STAT_C_ENABLE;
     }
}