mei: fix mei_poll operation

mei_poll returned with POLLIN w/o checking whether the operation
has really completed.
remove redundant check and locking in amthif specific handler

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

3 files changed, 27 insertions, 24 deletions

diff --git a/drivers/misc/mei/amthif.c b/drivers/misc/mei/amthif.c
index 7b6ed0bbfc9c..3c1fd87ee10b 100644
--- a/drivers/misc/mei/amthif.c
+++ b/drivers/misc/mei/amthif.c
@@ -362,6 +362,18 @@ int mei_amthif_write(struct mei_cl *cl, struct mei_cl_cb *cb)
         return mei_amthif_run_next_cmd(dev);
 }
 
+/**
+ * mei_amthif_poll - the amthif poll function
+ *
+ * @dev: the device structure
+ * @file: pointer to file structure
+ * @wait: pointer to poll_table structure
+ *
+ * Return: poll mask
+ *
+ * Locking: called under "dev->device_lock" lock
+ */
+
 unsigned int mei_amthif_poll(struct mei_device *dev,
                 struct file *file, poll_table *wait)
 {
@@ -369,19 +381,12 @@ unsigned int mei_amthif_poll(struct mei_device *dev,
 
         poll_wait(file, &dev->iamthif_cl.wait, wait);
 
-        mutex_lock(&dev->device_lock);
-        if (!mei_cl_is_connected(&dev->iamthif_cl)) {
-
-                mask = POLLERR;
-
-        } else if (dev->iamthif_state == MEI_IAMTHIF_READ_COMPLETE &&
-                   dev->iamthif_file_object == file) {
+        if (dev->iamthif_state == MEI_IAMTHIF_READ_COMPLETE &&
+            dev->iamthif_file_object == file) {
 
-                mask |= (POLLIN | POLLRDNORM);
-                dev_dbg(dev->dev, "run next amthif cb\n");
+                mask |= POLLIN | POLLRDNORM;
                 mei_amthif_run_next_cmd(dev);
         }
-        mutex_unlock(&dev->device_lock);
 
         return mask;
 }
diff --git a/drivers/misc/mei/client.c b/drivers/misc/mei/client.c
index b6fec4d15307..e5aeb6fd1ba4 100644
--- a/drivers/misc/mei/client.c
+++ b/drivers/misc/mei/client.c
@@ -1299,7 +1299,7 @@ void mei_cl_complete(struct mei_cl *cl, struct mei_cl_cb *cb)
         } else if (cb->fop_type == MEI_FOP_READ) {
                 list_add_tail(&cb->list, &cl->rd_completed);
                 if (waitqueue_active(&cl->rx_wait))
-                        wake_up_interruptible(&cl->rx_wait);
+                        wake_up_interruptible_all(&cl->rx_wait);
                 else
                         mei_cl_bus_rx_event(cl);
 
diff --git a/drivers/misc/mei/main.c b/drivers/misc/mei/main.c
index d80867e0d803..a1ec45054988 100644
--- a/drivers/misc/mei/main.c
+++ b/drivers/misc/mei/main.c
@@ -542,6 +542,7 @@ static long mei_compat_ioctl(struct file *file,
  */
 static unsigned int mei_poll(struct file *file, poll_table *wait)
 {
+        unsigned long req_events = poll_requested_events(wait);
         struct mei_cl *cl = file->private_data;
         struct mei_device *dev;
         unsigned int mask = 0;
@@ -558,22 +559,19 @@ static unsigned int mei_poll(struct file *file, poll_table *wait)
                 goto out;
         }
 
-        mutex_unlock(&dev->device_lock);
-
-
-        if (cl == &dev->iamthif_cl)
-                return mei_amthif_poll(dev, file, wait);
-
-        poll_wait(file, &cl->tx_wait, wait);
-
-        mutex_lock(&dev->device_lock);
-
-        if (!mei_cl_is_connected(cl)) {
-                mask = POLLERR;
+        if (cl == &dev->iamthif_cl) {
+                mask = mei_amthif_poll(dev, file, wait);
                 goto out;
         }
 
-        mask |= (POLLIN | POLLRDNORM);
+        if (req_events & (POLLIN | POLLRDNORM)) {
+                poll_wait(file, &cl->rx_wait, wait);
+
+                if (!list_empty(&cl->rd_completed))
+                        mask |= POLLIN | POLLRDNORM;
+                else
+                        mei_cl_read_start(cl, 0, file);
+        }
 
 out:
         mutex_unlock(&dev->device_lock);