pinctrl: core: Warn about NULL gpio_chip in pinctrl_ready_for_gpio_range()

If the gpio driver is confused about the numbers for gpio-ranges,
pinctrl_ready_for_gpio_range() may get called with invalid GPIO
causing a NULL pointer exception. Let's instead provide a warning
that allows fixing the problem and return with error.

Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c
index 69723e07036bafbd29c6d6deb66e2f7bd7f0133e..9638a00c67c2bd9a3735a632c99d01e9c2625e5d 100644 (file)
--- a/drivers/pinctrl/core.c
+++ b/drivers/pinctrl/core.c
@@ -349,6 +349,9 @@ static bool pinctrl_ready_for_gpio_range(unsigned gpio)
        struct pinctrl_gpio_range *range = NULL;
        struct gpio_chip *chip = gpio_to_chip(gpio);
 
+       if (WARN(!chip, "no gpio_chip for gpio%i?", gpio))
+               return false;
+
        mutex_lock(&pinctrldev_list_mutex);
 
        /* Loop over the pin controllers */