USB: Prepare for refactoring by adding extra udev checks.

The next patch will refactor the hub port code to rip out the recursive
call to hub_port_reset on a failed hot reset.  In preparation for that,
make sure all code paths can deal with being called with a NULL udev.
The usb_device will not be valid if warm reset was issued because a port
transitioned to the Inactive or Compliance Mode on a device connect.

This patch should have no effect on current behavior.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>

1 files changed, 13 insertions, 8 deletions

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 855bb0d6313d..c3368f978c44 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -2584,6 +2584,9 @@ static int hub_port_wait_reset(struct usb_hub *hub, int port1,
                                 return -ENOTCONN;
 
                         if ((portstatus & USB_PORT_STAT_ENABLE)) {
+                                if (!udev)
+                                        return 0;
+
                                 if (hub_is_wusb(hub))
                                         udev->speed = USB_SPEED_WIRELESS;
                                 else if (hub_is_superspeed(hub->hdev))
@@ -2627,13 +2630,15 @@ static void hub_port_finish_reset(struct usb_hub *hub, int port1,
                         struct usb_hcd *hcd;
                         /* TRSTRCY = 10 ms; plus some extra */
                         msleep(10 + 40);
-                        update_devnum(udev, 0);
-                        hcd = bus_to_hcd(udev->bus);
-                        /* The xHC may think the device is already reset,
-                         * so ignore the status.
-                         */
-                        if (hcd->driver->reset_device)
-                                hcd->driver->reset_device(hcd, udev);
+                        if (udev) {
+                                update_devnum(udev, 0);
+                                hcd = bus_to_hcd(udev->bus);
+                                /* The xHC may think the device is already
+                                 * reset, so ignore the status.
+                                 */
+                                if (hcd->driver->reset_device)
+                                        hcd->driver->reset_device(hcd, udev);
+                        }
                 }
                 /* FALL THROUGH */
         case -ENOTCONN:
@@ -2647,7 +2652,7 @@ static void hub_port_finish_reset(struct usb_hub *hub, int port1,
                         clear_port_feature(hub->hdev, port1,
                                         USB_PORT_FEAT_C_PORT_LINK_STATE);
                 }
-                if (!warm)
+                if (!warm && udev)
                         usb_set_device_state(udev, *status
                                         ? USB_STATE_NOTATTACHED
                                         : USB_STATE_DEFAULT);