diff options
Diffstat (limited to 'drivers/usb/host/ehci-hcd.c')
| -rw-r--r-- | drivers/usb/host/ehci-hcd.c | 45 |
1 files changed, 45 insertions, 0 deletions
diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c index a2ca9cbf280..2b72473544d 100644 --- a/drivers/usb/host/ehci-hcd.c +++ b/drivers/usb/host/ehci-hcd.c @@ -1024,6 +1024,51 @@ done: return; } +static void +ehci_endpoint_reset(struct usb_hcd *hcd, struct usb_host_endpoint *ep) +{ + struct ehci_hcd *ehci = hcd_to_ehci(hcd); + struct ehci_qh *qh; + int eptype = usb_endpoint_type(&ep->desc); + + if (eptype != USB_ENDPOINT_XFER_BULK && eptype != USB_ENDPOINT_XFER_INT) + return; + + rescan: + spin_lock_irq(&ehci->lock); + qh = ep->hcpriv; + + /* For Bulk and Interrupt endpoints we maintain the toggle state + * in the hardware; the toggle bits in udev aren't used at all. + * When an endpoint is reset by usb_clear_halt() we must reset + * the toggle bit in the QH. + */ + if (qh) { + if (!list_empty(&qh->qtd_list)) { + WARN_ONCE(1, "clear_halt for a busy endpoint\n"); + } else if (qh->qh_state == QH_STATE_IDLE) { + qh->hw_token &= ~cpu_to_hc32(ehci, QTD_TOGGLE); + } else { + /* It's not safe to write into the overlay area + * while the QH is active. Unlink it first and + * wait for the unlink to complete. + */ + if (qh->qh_state == QH_STATE_LINKED) { + if (eptype == USB_ENDPOINT_XFER_BULK) { + unlink_async(ehci, qh); + } else { + intr_deschedule(ehci, qh); + (void) qh_schedule(ehci, qh); + } + } + spin_unlock_irq(&ehci->lock); + schedule_timeout_uninterruptible(1); + goto rescan; + } + } + spin_unlock_irq(&ehci->lock); +} + static int ehci_get_frame (struct usb_hcd *hcd) { struct ehci_hcd *ehci = hcd_to_ehci (hcd); |