gpiolib: Check "gpio-ranges" before calling ->add_pin_ranges()

The ->add_pin_ranges() is supposed to be called for the backward
compatiblity on Device Tree platforms or non-DT ones. Ensure that
by checking presense of the "gpio-ranges" property.

This allows to clean up a few existing drivers to avoid duplication
of the check.

Signed-off-by: Andy Shevchenko <[email protected]>
Tested-by: Stefan Wahren <[email protected]>
Tested-by: Florian Fainelli <[email protected]>
Reviewed-by: Florian Fainelli <[email protected]>
Acked-by: Bartosz Golaszewski <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Linus Walleij <[email protected]>

Author: andy-shev

drivers/gpio/gpiolib.c

@@ -531,6 +531,14 @@ static void gpiochip_free_valid_mask(struct gpio_chip *gc)
 
 static int gpiochip_add_pin_ranges(struct gpio_chip *gc)
 {
+	/*
+	 * Device Tree platforms are supposed to use "gpio-ranges"
+	 * property. This check ensures that the ->add_pin_ranges()
+	 * won't be called for them.
+	 */
+	if (device_property_present(&gc->gpiodev->dev, "gpio-ranges"))
+		return 0;
+
 	if (gc->add_pin_ranges)
 		return gc->add_pin_ranges(gc);