[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, 10 deletions

diff --git a/drivers/usb/misc/usbtest.c b/drivers/usb/misc/usbtest.c
index 54799eb..d055196 100644
--- a/drivers/usb/misc/usbtest.c
+++ b/drivers/usb/misc/usbtest.c
@@ -1948,21 +1948,11 @@ usbtest_probe (struct usb_interface *intf, const struct usb_device_id *id)
 
 static int usbtest_suspend (struct usb_interface *intf, pm_message_t message)
 {
-	struct usbtest_dev	*dev = usb_get_intfdata (intf);
-
-	down (&dev->sem);
-	intf->dev.power.power_state = PMSG_SUSPEND;
-	up (&dev->sem);
 	return 0;
 }
 
 static int usbtest_resume (struct usb_interface *intf)
 {
-	struct usbtest_dev	*dev = usb_get_intfdata (intf);
-
-	down (&dev->sem);
-	intf->dev.power.power_state = PMSG_ON;
-	up (&dev->sem);
 	return 0;
 }