diff options
| -rw-r--r-- | drivers/usb/core/driver.c | 17 |
1 files changed, 12 insertions, 5 deletions
diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c index 631f30582481..b9f7f90aef82 100644 --- a/drivers/usb/core/driver.c +++ b/drivers/usb/core/driver.c @@ -932,7 +932,7 @@ static int autosuspend_check(struct usb_device *udev) { int i; struct usb_interface *intf; - long suspend_time; + unsigned long suspend_time; /* For autosuspend, fail fast if anything is in use or autosuspend * is disabled. Also fail if any interfaces require remote wakeup @@ -964,11 +964,18 @@ static int autosuspend_check(struct usb_device *udev) /* If everything is okay but the device hasn't been idle for long * enough, queue a delayed autosuspend request. */ - suspend_time -= jiffies; - if (suspend_time > 0) { - if (!timer_pending(&udev->autosuspend.timer)) + if (time_after(suspend_time, jiffies)) { + if (!timer_pending(&udev->autosuspend.timer)) { + + /* The value of jiffies may change between the + * time_after() comparison above and the subtraction + * below. That's okay; the system behaves sanely + * when a timer is registered for the present moment + * or for the past. + */ queue_delayed_work(ksuspend_usb_wq, &udev->autosuspend, - suspend_time); + suspend_time - jiffies); + } return -EAGAIN; } return 0; |