gpiolib: of: Correct error handling in of_get_named_gpiod_flags

Hans Holmberg · linusw · commit 7b8792bbdffd · 2015-01-15T18:31:47.000+01:00
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).

Cc: Stable &lt;stable@vger.kernel.org&gt;
Signed-off-by: Hans Holmberg &lt;hans.holmberg@intel.com&gt;
Reviewed-by: Alexandre Courbot &lt;acourbot@nvidia.com&gt;
Signed-off-by: Linus Walleij &lt;linus.walleij@linaro.org&gt;
diff --git 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;
