aboutsummaryrefslogtreecommitdiff
path: root/drivers/usb/host/ehci-hcd.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/usb/host/ehci-hcd.c')
-rw-r--r--drivers/usb/host/ehci-hcd.c45
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);