xhci: fix 10 second timeout on removal of PCI hotpluggable xhci controllers

BugLink: http://bugs.launchpad.net/bugs/1578798
commit 98d74f9ceaefc2b6c4a6440050163a83be0abede upstream.

PCI hotpluggable xhci controllers such as some Alpine Ridge solutions will
remove the xhci controller from the PCI bus when the last USB device is
disconnected.

Add a flag to indicate that the host is being removed to avoid queueing
configure_endpoint commands for the dropped endpoints.
For PCI hotplugged controllers this will prevent 5 second command timeouts
For static xhci controllers the configure_endpoint command is not needed
in the removal case as everything will be returned, freed, and the
controller is reset.

For now the flag is only set for PCI connected host controllers.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>

diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index 6a120a71ca3d2d8bc36641d47c7009bca146a11c..ea4fb4b0cd44da050192e23b5522e8e6f95295dd 100644 (file)
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -301,6 +301,7 @@ static void xhci_pci_remove(struct pci_dev *dev)
        struct xhci_hcd *xhci;
 
        xhci = hcd_to_xhci(pci_get_drvdata(dev));
+       xhci->xhc_state |= XHCI_STATE_REMOVING;
        if (xhci->shared_hcd) {
                usb_remove_hcd(xhci->shared_hcd);
                usb_put_hcd(xhci->shared_hcd);

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 007f182f874344b877a550b09fcf24b7925f0a75..d7e7329c50d881786267c1d8ea2e1181ccca92cc 100644 (file)
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -3998,7 +3998,8 @@ static int queue_command(struct xhci_hcd *xhci, struct xhci_command *cmd,
        int reserved_trbs = xhci->cmd_ring_reserved_trbs;
        int ret;
 
-       if (xhci->xhc_state) {
+       if ((xhci->xhc_state & XHCI_STATE_DYING) ||
+               (xhci->xhc_state & XHCI_STATE_HALTED)) {
                xhci_dbg(xhci, "xHCI dying or halted, can't queue_command\n");
                return -ESHUTDOWN;
        }

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index c6f9375199df3c21dae432902a1f199d358f7ba4..e4f5d1d78285d2b5511fd3d1b1acb718ee041fae 100644 (file)
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -146,7 +146,8 @@ static int xhci_start(struct xhci_hcd *xhci)
                                "waited %u microseconds.\n",
                                XHCI_MAX_HALT_USEC);
        if (!ret)
-               xhci->xhc_state &= ~(XHCI_STATE_HALTED | XHCI_STATE_DYING);
+               /* clear state flags. Including dying, halted or removing */
+               xhci->xhc_state = 0;
 
        return ret;
 }
@@ -2756,7 +2757,8 @@ int xhci_check_bandwidth(struct usb_hcd *hcd, struct usb_device *udev)
        if (ret <= 0)
                return ret;
        xhci = hcd_to_xhci(hcd);
-       if (xhci->xhc_state & XHCI_STATE_DYING)
+       if ((xhci->xhc_state & XHCI_STATE_DYING) ||
+               (xhci->xhc_state & XHCI_STATE_REMOVING))
                return -ENODEV;
 
        xhci_dbg(xhci, "%s called for udev %p\n", __func__, udev);
@@ -3803,7 +3805,7 @@ static int xhci_setup_device(struct usb_hcd *hcd, struct usb_device *udev,
 
        mutex_lock(&xhci->mutex);
 
-       if (xhci->xhc_state)    /* dying or halted */
+       if (xhci->xhc_state)    /* dying, removing or halted */
                goto out;
 
        if (!udev->slot_id) {

diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index e285be075b3129d9edbc8ef85299b68568f18740..6474663db69318972eae65ead63b8364c562a8c0 100644 (file)
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1605,6 +1605,7 @@ struct xhci_hcd {
  */
 #define XHCI_STATE_DYING       (1 << 0)
 #define XHCI_STATE_HALTED      (1 << 1)
+#define XHCI_STATE_REMOVING    (1 << 2)
        /* Statistics */
        int                     error_bitmask;
        unsigned int            quirks;