mei: fix waiting for wr_ctrl for corner cases.
authorAlexander Usyskin <alexander.usyskin@intel.com>
Wed, 20 Apr 2016 15:03:55 +0000 (11:03 -0400)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sat, 30 Apr 2016 21:08:08 +0000 (14:08 -0700)
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>
drivers/misc/mei/client.c

index 85ae11d410cc90d10c8390a224aff2b3dca666c6..eed254da63a8c79ebb95ff711aef5b4e8926f0d9 100644 (file)
@@ -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)