USB: xhci: Handle stalled control endpoints.

When a control endpoint stalls, the next control transfer will clear the
stall.  The USB core doesn't call down to the host controller driver's
endpoint_reset() method when control endpoints stall, so the xHCI driver
has to do all its stall handling for internal state in its interrupt handler.

When the host stalls on a control endpoint, it may stop on the data phase
or status phase of the control transfer.  Like other stalled endpoints,
the xHCI driver needs to queue a Reset Endpoint command and move the
hardware's control endpoint ring dequeue pointer past the failed control
transfer (with a Set TR Dequeue Pointer or a Configure Endpoint command).

Since the USB core doesn't call usb_hcd_reset_endpoint() for control
endpoints, we need to do this in interrupt context when we get notified of
the stalled transfer.  URBs may be queued to the hardware before these two
commands complete.  The endpoint queue will be restarted once both
commands complete.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 4 insertions, 0 deletions

diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 6aecede77ff6..b1abaeb62b4c 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -589,6 +589,7 @@ struct xhci_ep_ctx {
  */
 #define FORCE_EVENT     (0x1)
 #define ERROR_COUNT(p)  (((p) & 0x3) << 1)
+#define CTX_TO_EP_TYPE(p)       (((p) >> 3) & 0x7)
 #define EP_TYPE(p)      ((p) << 3)
 #define ISOC_OUT_EP     1
 #define BULK_OUT_EP     2
@@ -1231,6 +1232,9 @@ void xhci_find_new_dequeue_state(struct xhci_hcd *xhci,
 void xhci_queue_new_dequeue_state(struct xhci_hcd *xhci,
                 struct xhci_ring *ep_ring, unsigned int slot_id,
                 unsigned int ep_index, struct xhci_dequeue_state *deq_state);
+void xhci_cleanup_stalled_ring(struct xhci_hcd *xhci,
+                struct usb_device *udev, struct usb_host_endpoint *ep,
+                unsigned int ep_index, struct xhci_ring *ep_ring);
 
 /* xHCI roothub code */
 int xhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue, u16 wIndex,