mei: reduce flow control only for completed messages

This fixes bug when only first chunk of a large message split
by hbuf_max_len is written to the hardware.
All the consequent chunks will not get a new credit.

A regression introduced by the commit
0ef319c93cebff9f82bdd0cdbb298f2dd00acda8
mei: streamline write complete flow function

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

1 files changed, 4 insertions, 3 deletions

diff --git a/drivers/misc/mei/interrupt.c b/drivers/misc/mei/interrupt.c
index 74730713a8d3..5ee2f07c929d 100644
--- a/drivers/misc/mei/interrupt.c
+++ b/drivers/misc/mei/interrupt.c
@@ -356,13 +356,14 @@ static int mei_irq_thread_write_complete(struct mei_device *dev, s32 *slots,
                 return -ENODEV;
         }
 
-        if (mei_cl_flow_ctrl_reduce(cl))
-                return -ENODEV;
 
         cl->status = 0;
         cb->buf_idx += mei_hdr.length;
-        if (mei_hdr.msg_complete)
+        if (mei_hdr.msg_complete) {
+                if (mei_cl_flow_ctrl_reduce(cl))
+                        return -ENODEV;
                 list_move_tail(&cb->list, &dev->write_waiting_list.list);
+        }
 
         return 0;
 }