mailbox: handle failed named mailbox channel request

[ Upstream commit 25777e5784a7b417967460d4fcf9660d05a0c320 ]

Previously, if mbox_request_channel_byname was used with a name
which did not exist in the "mbox-names" property of a mailbox
client, the mailbox corresponding to the last entry in the
"mbox-names" list would be incorrectly selected.
With this patch, -EINVAL is returned if the named mailbox is
not found.

Signed-off-by: Morten Borup Petersen <morten_bp@live.dk>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/mailbox/mailbox.c b/drivers/mailbox/mailbox.c
index 537f4f6d009b2d0dbd1eeac62dd20212eef3fb02..44b49a2676f03fca40931710f292ede904c86c44 100644 (file)
--- a/drivers/mailbox/mailbox.c
+++ b/drivers/mailbox/mailbox.c
@@ -391,11 +391,13 @@ struct mbox_chan *mbox_request_channel_byname(struct mbox_client *cl,
 
        of_property_for_each_string(np, "mbox-names", prop, mbox_name) {
                if (!strncmp(name, mbox_name, strlen(name)))
-                       break;
+                       return mbox_request_channel(cl, index);
                index++;
        }
 
-       return mbox_request_channel(cl, index);
+       dev_err(cl->dev, "%s() could not locate channel named \"%s\"\n",
+               __func__, name);
+       return ERR_PTR(-EINVAL);
 }
 EXPORT_SYMBOL_GPL(mbox_request_channel_byname);