gpiolib: of: Correct error handling in of_get_named_gpiod_flags

commit 7b8792bbdffdff3abda704f89c6a45ea97afdc62 upstream.

of_get_named_gpiod_flags fails with -EPROBE_DEFER in cases
where the gpio chip is available and the GPIO translation fails.

This causes drivers to be re-probed erroneusly, and hides the
real problem(i.e. the GPIO number being out of range).

Signed-off-by: Hans Holmberg <hans.holmberg@intel.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>

diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c
index af7e25c9a9ae6d56d5765870f233830c7b4a9e5a..8f9f0ad91445a0efec0199d6babb42e321ae9b03 100644 (file)
--- a/drivers/gpio/gpiolib-of.c
+++ b/drivers/gpio/gpiolib-of.c
@@ -45,8 +45,14 @@ static int of_gpiochip_find_and_xlate(struct gpio_chip *gc, void *data)
                return false;
 
        ret = gc->of_xlate(gc, &gg_data->gpiospec, gg_data->flags);
-       if (ret < 0)
-               return false;
+       if (ret < 0) {
+               /* We've found the gpio chip, but the translation failed.
+                * Return true to stop looking and return the translation
+                * error via out_gpio
+                */
+               gg_data->out_gpio = ERR_PTR(ret);
+               return true;
+        }
 
        gg_data->out_gpio = gpiochip_get_desc(gc, ret);
        return true;