USB: ehci-dbgp: errata for EHCI debug controller initialization

On some EHCI usb debug controllers, the EHCI debug device will fail to
be seen after a port reset, after a warm reset.  Two options exist to
get the device to initialize correctly.

Option 1 is to unplug and plug in the device.

Option 2 is to use the EHCI port test to get the usb debug device to
start talking again.  At that point the debug controller port reset
will succeed.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
CC: dbrownell@users.sourceforge.net
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/include/linux/usb/ehci_def.h b/include/linux/usb/ehci_def.h
index 1909d92..af4b86f 100644
--- a/include/linux/usb/ehci_def.h
+++ b/include/linux/usb/ehci_def.h
@@ -105,6 +105,7 @@
 #define PORT_WKDISC_E	(1<<21)		/* wake on disconnect (enable) */
 #define PORT_WKCONN_E	(1<<20)		/* wake on connect (enable) */
 /* 19:16 for port testing */
+#define PORT_TEST_PKT	(0x4<<16)	/* Port Test Control - packet test */
 #define PORT_LED_OFF	(0<<14)
 #define PORT_LED_AMBER	(1<<14)
 #define PORT_LED_GREEN	(2<<14)