[PATCH] mfd: add null check before pointer dereference

[Gustavo A. R. Silva]

Add NULL check before dereferencing pointer of_id in order to avoid
a potential NULL pointer dereference.

Addresses-Coverity-ID: 1408829
Cc: Charles Keepax <ckee...@opensource.wolfsonmicro.com>
Signed-off-by: Gustavo A. R. Silva <garsi...@embeddedor.com>
---
 drivers/mfd/wm831x-i2c.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/mfd/wm831x-i2c.c b/drivers/mfd/wm831x-i2c.c
index 781af06..2d48f41 100644
--- a/drivers/mfd/wm831x-i2c.c
+++ b/drivers/mfd/wm831x-i2c.c
@@ -37,6 +37,10 @@ static int wm831x_i2c_probe(struct i2c_client *i2c,
 
        if (i2c->dev.of_node) {
                of_id = of_match_device(wm831x_of_match, &i2c->dev);
+               if (!of_id) {
+                       dev_err(&i2c->dev, "Failed to find matching id\n");
+                       return -EINVAL;
+               }
                type = (enum wm831x_parent)of_id->data;
        } else {
                type = (enum wm831x_parent)id->driver_data;
-- 
2.5.0