usbcore: resume device resume recursion

This patch (as717b) removes the existing recursion in hub resume code:
Resuming a hub will no longer automatically resume the devices attached
to the hub.

At the same time, it adds one level of recursion: Suspending a USB
device will automatically suspend all the device's interfaces.  Failure
at an intermediate stage will cause all the already-suspended interfaces
to be resumed. Attempts to suspend or resume an interface by itself will
do nothing, although they won't return an error.  Thus the regular
system-suspend and system-resume procedures should continue to work as
before; only runtime PM will be affected.

The patch also removes the code that tests state of the interfaces
before suspending a device.  It's no longer needed, since everything
gets suspended together.


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

1 files changed, 0 insertions, 14 deletions

diff --git a/drivers/usb/core/generic.c b/drivers/usb/core/generic.c
index 1522195de715..b6dacd7551d2 100644
--- a/drivers/usb/core/generic.c
+++ b/drivers/usb/core/generic.c
@@ -184,22 +184,8 @@ static void generic_disconnect(struct usb_device *udev)
 
 #ifdef  CONFIG_PM
 
-static int verify_suspended(struct device *dev, void *unused)
-{
-        if (dev->driver == NULL)
-                return 0;
-        return (dev->power.power_state.event == PM_EVENT_ON) ? -EBUSY : 0;
-}
-
 static int generic_suspend(struct usb_device *udev, pm_message_t msg)
 {
-        int     status;
-
-        /* rule out bogus requests through sysfs */
-        status = device_for_each_child(&udev->dev, NULL, verify_suspended);
-        if (status)
-                return status;
-
         /* USB devices enter SUSPEND state through their hubs, but can be
          * marked for FREEZE as soon as their children are already idled.
          * But those semantics are useless, so we equate the two (sigh).