From: Joel Stanley <j...@jms.id.au>

We can't halt the host controller immediately when first HCD is removed as
it will cause problems if we have devices attached to the second (primary)
HCD, like a keyboard.

We've been carrying this in our Linux-as-a-bootloader environment for a
little while now. The machines all have the same TI TUSB73x0 part,
and when we kexec the devices don't come back until a system power cycle.

[minor adjustments, code comments and remove HALT check  -Mathias]
Signed-off-by: Joel Stanley <j...@jms.id.au>
Signed-off-by: Mathias Nyman <mathias.ny...@linux.intel.com>
---
 drivers/usb/host/xhci.c | 20 ++++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index e523dbd..5ecba7c 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -692,21 +692,21 @@ void xhci_stop(struct usb_hcd *hcd)
 
        mutex_lock(&xhci->mutex);
 
-       if (!(xhci->xhc_state & XHCI_STATE_HALTED)) {
-               spin_lock_irq(&xhci->lock);
-
-               xhci->xhc_state |= XHCI_STATE_HALTED;
-               xhci->cmd_ring_state = CMD_RING_STATE_STOPPED;
-               xhci_halt(xhci);
-               xhci_reset(xhci);
-               spin_unlock_irq(&xhci->lock);
-       }
-
+       /* Only halt host and free memory after both hcds are removed */
        if (!usb_hcd_is_primary_hcd(hcd)) {
+               /* usb core will free this hcd shortly, unset pointer */
+               xhci->shared_hcd = NULL;
                mutex_unlock(&xhci->mutex);
                return;
        }
 
+       spin_lock_irq(&xhci->lock);
+       xhci->xhc_state |= XHCI_STATE_HALTED;
+       xhci->cmd_ring_state = CMD_RING_STATE_STOPPED;
+       xhci_halt(xhci);
+       xhci_reset(xhci);
+       spin_unlock_irq(&xhci->lock);
+
        xhci_cleanup_msix(xhci);
 
        /* Deleting Compliance Mode Recovery Timer */
-- 
1.9.1

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