[PATCH 3.8 025/166] usb: hub: Use correct reset for wedged USB3 devices that are NOTATTACHED

[Kamal Mostafa]

3.8.13.16 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Julius Werner <jwerner at chromium.org>

commit 2d51f3cd11f414c56a87dc018196b85fd50b04a4 upstream.

This patch adds a check for USB_STATE_NOTATTACHED to the
hub_port_warm_reset_required() workaround for ports that end up in
Compliance Mode in hub_events() when trying to decide which reset
function to use. Trying to call usb_reset_device() with a NOTATTACHED
device will just fail and leave the port broken.

Signed-off-by: Julius Werner <jwerner at chromium.org>
Acked-by: Alan Stern <stern at rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
[ kamal: backport to 3.8 (context) ]
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/usb/core/hub.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 1ac190b..edbf39f 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -4764,7 +4764,9 @@ static void hub_events(void)
 					hub->ports[i - 1]->child;
 
 				dev_dbg(hub_dev, "warm reset port %d\n", i);
-				if (!udev) {
+				if (!udev ||
+				    !(portstatus & USB_PORT_STAT_CONNECTION) ||
+				    udev->state == USB_STATE_NOTATTACHED) {
 					status = hub_port_reset(hub, i,
 							NULL, HUB_BH_RESET_TIME,
 							true);
-- 
1.8.3.2