2 files changed, 11 insertions, 6 deletions

diff --git a/drivers/mailbox/mailbox.c b/drivers/mailbox/mailbox.c
index 19b491d2964f..c3c42d42d017 100644
--- a/drivers/mailbox/mailbox.c
+++ b/drivers/mailbox/mailbox.c
@@ -318,7 +318,7 @@ struct mbox_chan *mbox_request_channel(struct mbox_client *cl, int index)
                 return ERR_PTR(-ENODEV);
         }
 
-        chan = NULL;
+        chan = ERR_PTR(-EPROBE_DEFER);
         list_for_each_entry(mbox, &mbox_cons, node)
                 if (mbox->dev->of_node == spec.np) {
                         chan = mbox->of_xlate(mbox, &spec);
@@ -327,7 +327,12 @@ struct mbox_chan *mbox_request_channel(struct mbox_client *cl, int index)
 
         of_node_put(spec.np);
 
-        if (!chan || chan->cl || !try_module_get(mbox->dev->driver->owner)) {
+        if (IS_ERR(chan)) {
+                mutex_unlock(&con_mutex);
+                return chan;
+        }
+
+        if (chan->cl || !try_module_get(mbox->dev->driver->owner)) {
                 dev_dbg(dev, "%s: mailbox not free\n", __func__);
                 mutex_unlock(&con_mutex);
                 return ERR_PTR(-EBUSY);
@@ -390,7 +395,7 @@ of_mbox_index_xlate(struct mbox_controller *mbox,
         int ind = sp->args[0];
 
         if (ind >= mbox->num_chans)
-                return NULL;
+                return ERR_PTR(-EINVAL);
 
         return &mbox->chans[ind];
 }
diff --git a/drivers/mailbox/omap-mailbox.c b/drivers/mailbox/omap-mailbox.c
index 03f8545ba037..a3dbfd9c6479 100644
--- a/drivers/mailbox/omap-mailbox.c
+++ b/drivers/mailbox/omap-mailbox.c
@@ -639,18 +639,18 @@ static struct mbox_chan *omap_mbox_of_xlate(struct mbox_controller *controller,
 
         mdev = container_of(controller, struct omap_mbox_device, controller);
         if (WARN_ON(!mdev))
-                return NULL;
+                return ERR_PTR(-EINVAL);
 
         node = of_find_node_by_phandle(phandle);
         if (!node) {
                 pr_err("%s: could not find node phandle 0x%x\n",
                        __func__, phandle);
-                return NULL;
+                return ERR_PTR(-ENODEV);
         }
 
         mbox = omap_mbox_device_find(mdev, node->name);
         of_node_put(node);
-        return mbox ? mbox->chan : NULL;
+        return mbox ? mbox->chan : ERR_PTR(-ENOENT);
 }
 
 static int omap_mbox_probe(struct platform_device *pdev)