HID mouse: Don't include NAKs in error count. From Leo

ChangeLog

@@ -7196,3 +7196,5 @@
 	  keyboard and mouse classes if so configured.  From Leo (2014-4-17).
 	* include/nuttx/usb/usbhost:  Fix some USB HID-related conditional
 	  compilation.  From Leo (2014-4-17).
+	* drivers/usbhost/usbhost_hidmouse.c: Don't include NAKs from the device
+	  in the error count.  From Leo (2014-4-17).

drivers/usbhost/usbhost_hidmouse.c

@@ -1082,10 +1082,17 @@ static int usbhost_mouse_poll(int argc, char *argv[])
        */
 
       if (ret != OK)
+        {
+          /* If DRVR_TRANSFER() returns EAGAIN, that simply means that
+           * the devices was not ready and has NAK'ed the transfer.  That
+           * no be treated as an error (unless it persists for a long
+           * time).
+           */
+
+          udbg("ERROR: DRVR_TRANSFER returned: %d/%d\n", ret, nerrors);
+          if (ret != -EAGAIN)
             {
               nerrors++;
-          udbg("ERROR: DRVR_TRANSFER returned: %d/%d\n",
-               ret, nerrors);
 
               if (nerrors > 200)
                 {
@@ -1093,6 +1100,7 @@ static int usbhost_mouse_poll(int argc, char *argv[])
                   break;
                 }
             }
+        }
 
       /* The report was received correctly.  But ignore the mouse data if no
        * task has opened the driver.

include/nuttx/usb/usbhost.h

@@ -1,7 +1,7 @@
 /************************************************************************************
  * include/nuttx/usb/usbhost.h
  *
- *   Copyright (C) 2010-2013 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2010-2014 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * References: