gpio: gpiolib-devprop: Check chip->parent pointer before dereferencing

Confirm the chip->parent is valid before dereferencing because
the parent parameter is optional.

Signed-off-by: Thor Thayer <tthayer@opensource.altera.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 5 insertions, 0 deletions

diff --git a/drivers/gpio/gpiolib-devprop.c b/drivers/gpio/gpiolib-devprop.c
index 17bfc41692ef..27f383bda7d9 100644
--- a/drivers/gpio/gpiolib-devprop.c
+++ b/drivers/gpio/gpiolib-devprop.c
@@ -31,6 +31,11 @@ void devprop_gpiochip_set_names(struct gpio_chip *chip)
         const char **names;
         int ret, i;
 
+        if (!chip->parent) {
+                dev_warn(&gdev->dev, "GPIO chip parent is NULL\n");
+                return;
+        }
+
         ret = device_property_read_string_array(chip->parent, "gpio-line-names",
                                                 NULL, 0);
         if (ret < 0)