xhci: Return canceled URBs immediately when host is halted.

When the xHCI host controller is halted, it won't respond to commands
placed on the command ring.  So if an URB is cancelled after the first
roothub is deallocated, it will try to place a stop endpoint command on
the command ring, which will fail.  The command watchdog timer will fire
after five seconds, and the host controller will be marked as dying, and
all URBs will be completed.

Add a flag to the xHCI's internal state variable for when the host
controller is halted.  Immediately return the canceled URB if the host
controller is halted.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 238ebe158b8317df4e0b0361a39b3ba4b41a0fa1..2c11411ca5f5f2f413dbc5f31582d44a0534bb27 100644 (file)
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -98,11 +98,15 @@ void xhci_quiesce(struct xhci_hcd *xhci)
  */
 int xhci_halt(struct xhci_hcd *xhci)
 {
+       int ret;
        xhci_dbg(xhci, "// Halt the HC\n");
        xhci_quiesce(xhci);
 
-       return handshake(xhci, &xhci->op_regs->status,
+       ret = handshake(xhci, &xhci->op_regs->status,
                        STS_HALT, STS_HALT, XHCI_MAX_HALT_USEC);
+       if (!ret)
+               xhci->xhc_state |= XHCI_STATE_HALTED;
+       return ret;
 }
 
 /*
@@ -129,6 +133,8 @@ int xhci_start(struct xhci_hcd *xhci)
                xhci_err(xhci, "Host took too long to start, "
                                "waited %u microseconds.\n",
                                XHCI_MAX_HALT_USEC);
+       if (!ret)
+               xhci->xhc_state &= ~XHCI_STATE_HALTED;
        return ret;
 }
 
@@ -1212,7 +1218,7 @@ int xhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
        if (ret || !urb->hcpriv)
                goto done;
        temp = xhci_readl(xhci, &xhci->op_regs->status);
-       if (temp == 0xffffffff) {
+       if (temp == 0xffffffff || (xhci->xhc_state & XHCI_STATE_HALTED)) {
                xhci_dbg(xhci, "HW died, freeing TD.\n");
                urb_priv = urb->hcpriv;
 

diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index e9217bb288ad44affc859d1f9e1ad599a9d31c64..e69f1cdf4b5bb8b05b8f8942a443afc3dbfa1f01 100644 (file)
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1260,6 +1260,7 @@ struct xhci_hcd {
  * There are no reports of xHCI host controllers that display this issue.
  */
 #define XHCI_STATE_DYING       (1 << 0)
+#define XHCI_STATE_HALTED      (1 << 1)
        /* Statistics */
        int                     error_bitmask;
        unsigned int            quirks;