[PATCH] usb_interface power state

This updates the handling of power state for USB interfaces.

  - Formalizes an existing invariant:  interface "power state" is a boolean:
    ON when I/O is allowed, and FREEZE otherwise.  It does so by defining
    some inlined helpers, then using them.

  - Adds a useful invariant:  the only interfaces marked active are those
    bound to non-suspended drivers.  Later patches build on this invariant.

  - Simplifies the interface driver API (and removes some error paths) by
    removing the requirement that they record power state changes during
    suspend and resume callbacks.  Now usbcore does that.

A few drivers were simplified to address that last change.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

 drivers/usb/core/hub.c       |   33 +++++++++------------
 drivers/usb/core/message.c   |    1
 drivers/usb/core/usb.c       |   65 +++++++++++++++++++++++++++++++++----------
 drivers/usb/core/usb.h       |   18 +++++++++++
 drivers/usb/input/hid-core.c |    2 -
 drivers/usb/misc/usbtest.c   |   10 ------
 drivers/usb/net/pegasus.c    |    2 -
 drivers/usb/net/usbnet.c     |    2 -
 8 files changed, 85 insertions(+), 48 deletions(-)

1 files changed, 0 insertions, 2 deletions

diff --git a/drivers/usb/input/hid-core.c b/drivers/usb/input/hid-core.c
index 411a0645a7a3..f7fcce731f54 100644
--- a/drivers/usb/input/hid-core.c
+++ b/drivers/usb/input/hid-core.c
@@ -1887,7 +1887,6 @@ static int hid_suspend(struct usb_interface *intf, pm_message_t message)
         struct hid_device *hid = usb_get_intfdata (intf);
 
         usb_kill_urb(hid->urbin);
-        intf->dev.power.power_state = PMSG_SUSPEND;
         dev_dbg(&intf->dev, "suspend\n");
         return 0;
 }
@@ -1897,7 +1896,6 @@ static int hid_resume(struct usb_interface *intf)
         struct hid_device *hid = usb_get_intfdata (intf);
         int status;
 
-        intf->dev.power.power_state = PMSG_ON;
         if (hid->open)
                 status = usb_submit_urb(hid->urbin, GFP_NOIO);
         else