usb: core: hub: fix race condition about TRSMRCY of resume

This may happen if the port becomes resume status exactly
when usb_port_resume() gets port status, it still need provide
a TRSMCRY time before access the device.

CC: <stable@vger.kernel.org>
Reported-by: Tianping Fang <tianping.fang@mediatek.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/20210512020738.52961-1-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index b2bc4b7..fc7d6cd 100644 (file)
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -3642,9 +3642,6 @@ int usb_port_resume(struct usb_device *udev, pm_message_t msg)
                 * sequence.
                 */
                status = hub_port_status(hub, port1, &portstatus, &portchange);
-
-               /* TRSMRCY = 10 msec */
-               msleep(10);
        }
 
  SuspendCleared:
@@ -3659,6 +3656,9 @@ int usb_port_resume(struct usb_device *udev, pm_message_t msg)
                                usb_clear_port_feature(hub->hdev, port1,
                                                USB_PORT_FEAT_C_SUSPEND);
                }
+
+               /* TRSMRCY = 10 msec */
+               msleep(10);
        }
 
        if (udev->persist_enabled)