USB: Export URB statistics for powertop

powertop currently tracks interrupts generated by uhci, ehci, and ohci,
but it has no way of telling which USB device to blame USB bus activity on.
This patch exports the number of URBs that are submitted for a given device.
Cat the file 'urbnum' in /sys/bus/usb/devices/.../

Signed-off-by: Sarah Sharp <sarah.a.sharp@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/linux/usb.h b/include/linux/usb.h
index e5b35e0dca23..c10935fdc03a 100644
--- a/include/linux/usb.h
+++ b/include/linux/usb.h
@@ -415,6 +415,7 @@ struct usb_device {
 
         int pm_usage_cnt;               /* usage counter for autosuspend */
         u32 quirks;                     /* quirks of the whole device */
+        atomic_t urbnum;                /* number of URBs submitted for the whole device */
 
 #ifdef CONFIG_PM
         struct delayed_work autosuspend; /* for delayed autosuspends */