gpio: of: Allow -gpio suffix for property names

Many bindings use the -gpio suffix in property names. Support this in
addition to the -gpios suffix when requesting GPIOs using the new
descriptor-based API.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpiolib.c

@@ -2600,17 +2600,23 @@ static struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id,
 				      unsigned int idx,
 				      enum gpio_lookup_flags *flags)
 {
+	static const char *suffixes[] = { "gpios", "gpio" };
 	char prop_name[32]; /* 32 is max size of property name */
 	enum of_gpio_flags of_flags;
 	struct gpio_desc *desc;
+	unsigned int i;
 
+	for (i = 0; i < ARRAY_SIZE(suffixes); i++) {
 		if (con_id)
-		snprintf(prop_name, 32, "%s-gpios", con_id);
+			snprintf(prop_name, 32, "%s-%s", con_id, suffixes[i]);
 		else
-		snprintf(prop_name, 32, "gpios");
+			snprintf(prop_name, 32, "%s", suffixes[i]);
 
 		desc = of_get_named_gpiod_flags(dev->of_node, prop_name, idx,
 						&of_flags);
+		if (!IS_ERR(desc))
+			break;
+	}
 
 	if (IS_ERR(desc))
 		return desc;