On Thu, Aug 25, 2011 at 12:11:32PM -0400, Alan Stern wrote:
> On Thu, 25 Aug 2011, Andiry Xu wrote:
>
> > Current waiting time for warm(BH) reset in hub_port_warm_reset() is too
> > short for xHC host to complete the warm reset and report a BH reset
> > change.
> >
> > This patch extends the waiting time for warm reset and merges the function
> > into hub_port_reset(), so it can handle both cold reset and warm reset.
> >
> > This fixes the issue that driver fails to clear BH reset change and port is
> > "dead".
>
> This code looks a little odd.
>
> > @@ -2046,28 +2047,43 @@ static int hub_port_wait_reset(struct usb_hub *hub, int port1,
> > if (ret < 0)
> > return ret;
> >
> > - /* Device went away? */
> > - if (!(portstatus & USB_PORT_STAT_CONNECTION))
> > - return -ENOTCONN;
> > -
> > - /* bomb out completely if the connection bounced */
> > - if ((portchange & USB_PORT_STAT_C_CONNECTION))
> > - return -ENOTCONN;
> > -
> > - /* if we`ve finished resetting, then break out of the loop */
> > - if (!(portstatus & USB_PORT_STAT_RESET) &&
> > - (portstatus & USB_PORT_STAT_ENABLE)) {
> > - if (hub_is_wusb(hub))
> > - udev->speed = USB_SPEED_WIRELESS;
> > - else if (hub_is_superspeed(hub->hdev))
> > - udev->speed = USB_SPEED_SUPER;
> > - else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
> > - udev->speed = USB_SPEED_HIGH;
> > - else if (portstatus & USB_PORT_STAT_LOW_SPEED)
> > - udev->speed = USB_SPEED_LOW;
> > - else
> > - udev->speed = USB_SPEED_FULL;
> > - return 0;
> > + if (!warm) {
>
> What's wrong with running all the code above for a warm reset?
I think the device won't show up as connected when a warm reset
completes until the host controller driver clears the warm reset change
bit. I'd have to look at my logs to verify this though.
> > + } else {
> > + if (portchange & USB_PORT_STAT_C_BH_RESET) {
> > + clear_port_feature(hub->hdev, port1,
> > + USB_PORT_FEAT_C_BH_PORT_RESET);
> > +
> > + if (portchange & USB_PORT_STAT_C_LINK_STATE)
> > + clear_port_feature(hub->hdev, port1,
> > + USB_PORT_FEAT_C_PORT_LINK_STATE);
> > +
>
> Why do you need to clear these features specially for a warm reset?
> Can't they be cleared the same way as USB_PORT_FEAT_C_RESET?
I don't understand your question. Are you trying to say that the xHCI
host controller should clear the BH reset connect change when the USB
core asks it to clear the RESET change? Or are you suggesting something
else?
Sarah Sharp
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