@@ -52,6 +52,7 @@
* endpoint rings; it generates events on the event ring for these.
*/
+#include <linux/jiffies.h>
#include <linux/scatterlist.h>
#include <linux/slab.h>
#include <linux/dma-mapping.h>
@@ -1158,16 +1159,35 @@ static void xhci_handle_cmd_stop_ep(struct xhci_hcd *xhci, int slot_id,
return;
case EP_STATE_STOPPED:
/*
- * NEC uPD720200 sometimes sets this state and fails with
- * Context Error while continuing to process TRBs.
- * Be conservative and trust EP_CTX_STATE on other chips.
+ * Per xHCI 4.6.9, Stop Endpoint command on a Stopped
+ * EP is a Context State Error, and EP stays Stopped.
+ *
+ * But maybe it failed on Halted, and somebody ran Reset
+ * Endpoint later. EP state is now Stopped and EP_HALTED
+ * still set because Reset EP handler will run after us.
+ */
+ if (ep->ep_state & EP_HALTED)
+ break;
+ /*
+ * On some HCs EP state remains Stopped for some tens of
+ * us to a few ms or more after a doorbell ring, and any
+ * new Stop Endpoint fails without aborting the restart.
+ * This handler may run quickly enough to still see this
+ * Stopped state, but it will soon change to Running.
+ *
+ * Assume this bug on unexpected Stop Endpoint failures.
+ * Keep retrying until the EP starts and stops again, on
+ * chips where this is known to help. Wait for 100ms.
*/
if (!(xhci->quirks & XHCI_NEC_HOST))
break;
+ if (time_is_before_jiffies(ep->stop_time + msecs_to_jiffies(100)))
+ break;
fallthrough;
case EP_STATE_RUNNING:
/* Race, HW handled stop ep cmd before ep was running */
- xhci_dbg(xhci, "Stop ep completion ctx error, ep is running\n");
+ xhci_dbg(xhci, "Stop ep completion ctx error, ctx_state %d\n",
+ GET_EP_CTX_STATE(ep_ctx));
command = xhci_alloc_command(xhci, false, GFP_ATOMIC);
if (!command) {
@@ -8,6 +8,7 @@
* Some code borrowed from the Linux EHCI driver.
*/
+#include <linux/jiffies.h>
#include <linux/pci.h>
#include <linux/iommu.h>
#include <linux/iopoll.h>
@@ -1764,6 +1765,7 @@ static int xhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
ret = -ENOMEM;
goto done;
}
+ ep->stop_time = jiffies;
ep->ep_state |= EP_STOP_CMD_PENDING;
xhci_queue_stop_endpoint(xhci, command, urb->dev->slot_id,
ep_index, 0);
@@ -691,6 +691,7 @@ struct xhci_virt_ep {
/* Bandwidth checking storage */
struct xhci_bw_info bw_info;
struct list_head bw_endpoint_list;
+ unsigned long stop_time;
/* Isoch Frame ID checking storage */
int next_frame_id;
/* Use new Isoch TRB layout needed for extended TBC support */