+/**
+ * usb_autopm_put_interface_async - decrement a USB interface's PM-usage counter
+ * @intf: the usb_interface whose counter should be decremented
+ *
+ * This routine does essentially the same thing as
+ * usb_autopm_put_interface(): it decrements @intf's usage counter and
+ * queues a delayed autosuspend request if the counter is <= 0. The
+ * difference is that it does not acquire the device's pm_mutex;
+ * callers must handle all synchronization issues themselves.
+ *
+ * Typically a driver would call this routine during an URB's completion
+ * handler, if no more URBs were pending.
+ *
+ * This routine can run in atomic context.
+ */
+void usb_autopm_put_interface_async(struct usb_interface *intf)
+{
+ struct usb_device *udev = interface_to_usbdev(intf);
+ int status = 0;
+
+ if (intf->condition == USB_INTERFACE_UNBOUND) {
+ status = -ENODEV;
+ } else {
+ udev->last_busy = jiffies;
+ --intf->pm_usage_cnt;
+ if (udev->autosuspend_disabled || udev->autosuspend_delay < 0)
+ status = -EPERM;
+ else if (intf->pm_usage_cnt <= 0 &&
+ !timer_pending(&udev->autosuspend.timer)) {
+ queue_delayed_work(ksuspend_usb_wq, &udev->autosuspend,
+ round_jiffies_relative(
+ udev->autosuspend_delay));
+ }
+ }
+ dev_vdbg(&intf->dev, "%s: status %d cnt %d\n",
+ __func__, status, intf->pm_usage_cnt);
+}
+EXPORT_SYMBOL_GPL(usb_autopm_put_interface_async);
+