musb: make initial HNP roleswitch work (v2)

Minor HNP bugfixes, so the initial role switch works:

 - A-Device:
     * disconnect-during-suspend enters A_PERIPHERAL state
     * kill OTG timer after reset as A_PERIPHERAL ...
     * ... and also pass that reset to the gadget
     * once HNP succeeds, clear the "ignore_disconnect" flag
     * from A_PERIPHERAL, disconnect transitions to A_WAIT_BCON

 - B-Device:
     * kill OTG timer on entry to B_HOST state (HNP succeeded)
     * once HNP succeeds, clear "ignore_disconnect" flag
     * kick the root hub only _after_ the state is adjusted

Other state transitions are left alone.  Notably, exit paths from
the "roles have switched" state ... A_PERIPHERAL handling of that
stays seriously broken.

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

drivers/usb/musb/musb_virthub.c

@@ -187,8 +187,17 @@ void musb_root_disconnect(struct musb *musb)
 	musb->is_active = 0;
 
 	switch (musb->xceiv->state) {
-	case OTG_STATE_A_HOST:
 	case OTG_STATE_A_SUSPEND:
+#ifdef	CONFIG_USB_MUSB_OTG
+		if (is_otg_enabled(musb)
+				&& musb->xceiv->host->b_hnp_enable) {
+			musb->xceiv->state = OTG_STATE_A_PERIPHERAL;
+			musb->g.is_a_peripheral = 1;
+			break;
+		}
+#endif
+		/* FALLTHROUGH */
+	case OTG_STATE_A_HOST:
 		musb->xceiv->state = OTG_STATE_A_WAIT_BCON;
 		musb->is_active = 0;
 		break;