From 7ff4bdd45448936363dc6dc6c851112b5c08e209 Mon Sep 17 00:00:00 2001
From: Alexander Usyskin <alexander.usyskin@intel.com>
Date: Wed, 20 Apr 2016 11:03:55 -0400
Subject: mei: fix waiting for wr_ctrl for corner cases.

A control message reply may not be received if either a link reset has
occurred or disconnection is initiated by the FW.
In the both cases the client state will be set straight to DISCONNECTED
and the driver will wait till timeout.
Adding DISCONNECTED state in the waiting condition will release the
client from the stall.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/misc/mei/client.c b/drivers/misc/mei/client.c
index 85ae11d..eed254d 100644
--- a/drivers/misc/mei/client.c
+++ b/drivers/misc/mei/client.c
@@ -727,6 +727,11 @@ static void mei_cl_wake_all(struct mei_cl *cl)
 		cl_dbg(dev, cl, "Waking up waiting for event clients!\n");
 		wake_up_interruptible(&cl->ev_wait);
 	}
+	/* synchronized under device mutex */
+	if (waitqueue_active(&cl->wait)) {
+		cl_dbg(dev, cl, "Waking up ctrl write clients!\n");
+		wake_up_interruptible(&cl->wait);
+	}
 }
 
 /**
@@ -879,12 +884,15 @@ static int __mei_cl_disconnect(struct mei_cl *cl)
 	}
 
 	mutex_unlock(&dev->device_lock);
-	wait_event_timeout(cl->wait, cl->state == MEI_FILE_DISCONNECT_REPLY,
+	wait_event_timeout(cl->wait,
+			   cl->state == MEI_FILE_DISCONNECT_REPLY ||
+			   cl->state == MEI_FILE_DISCONNECTED,
 			   mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
 	mutex_lock(&dev->device_lock);
 
 	rets = cl->status;
-	if (cl->state != MEI_FILE_DISCONNECT_REPLY) {
+	if (cl->state != MEI_FILE_DISCONNECT_REPLY &&
+	    cl->state != MEI_FILE_DISCONNECTED) {
 		cl_dbg(dev, cl, "timeout on disconnect from FW client.\n");
 		rets = -ETIME;
 	}
@@ -1085,6 +1093,7 @@ int mei_cl_connect(struct mei_cl *cl, struct mei_me_client *me_cl,
 	mutex_unlock(&dev->device_lock);
 	wait_event_timeout(cl->wait,
 			(cl->state == MEI_FILE_CONNECTED ||
+			 cl->state == MEI_FILE_DISCONNECTED ||
 			 cl->state == MEI_FILE_DISCONNECT_REQUIRED ||
 			 cl->state == MEI_FILE_DISCONNECT_REPLY),
 			mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
@@ -1333,8 +1342,9 @@ int mei_cl_notify_request(struct mei_cl *cl,
 	}
 
 	mutex_unlock(&dev->device_lock);
-	wait_event_timeout(cl->wait, cl->notify_en == request,
-			mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
+	wait_event_timeout(cl->wait,
+			   cl->notify_en == request || !mei_cl_is_connected(cl),
+			   mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
 	mutex_lock(&dev->device_lock);
 
 	if (cl->notify_en != request && !cl->status)
-- 
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