USB: more autosuspend timer stuff

This patch (as879) ties up some loose ends from an earlier patch.
These are things I didn't think to include at the time but which
clearly belonged there.

	If an autosuspend fails because driver activity races with
	the autosuspend call, restart the autosuspend timer.

	When a device is resumed by an external request, it counts
	as device activity and should update the last_busy time so
	that the next autoresume won't occur immediately.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
index b9f7f90..2619986 100644 (file)
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -983,7 +983,10 @@ static int autosuspend_check(struct usb_device *udev)
 
 #else
 
-#define autosuspend_check(udev)                0
+static inline int autosuspend_check(struct usb_device *udev)
+{
+       return 0;
+}
 
 #endif /* CONFIG_USB_SUSPEND */
 
@@ -1041,7 +1044,6 @@ static int usb_suspend_both(struct usb_device *udev, pm_message_t msg)
                if (status < 0)
                        goto done;
        }
-       cancel_delayed_work(&udev->autosuspend);
 
        /* Suspend all the interfaces and then udev itself */
        if (udev->actconfig) {
@@ -1062,9 +1064,16 @@ static int usb_suspend_both(struct usb_device *udev, pm_message_t msg)
                        usb_resume_interface(intf);
                }
 
+               /* Try another autosuspend when the interfaces aren't busy */
+               if (udev->auto_pm)
+                       autosuspend_check(udev);
+
        /* If the suspend succeeded, propagate it up the tree */
-       } else if (parent)
-               usb_autosuspend_device(parent);
+       } else {
+               cancel_delayed_work(&udev->autosuspend);
+               if (parent)
+                       usb_autosuspend_device(parent);
+       }
 
  done:
        // dev_dbg(&udev->dev, "%s: status %d\n", __FUNCTION__, status);
@@ -1475,6 +1484,7 @@ int usb_external_resume_device(struct usb_device *udev)
        usb_pm_lock(udev);
        udev->auto_pm = 0;
        status = usb_resume_both(udev);
+       udev->last_busy = jiffies;
        usb_pm_unlock(udev);
 
        /* Now that the device is awake, we can start trying to autosuspend