[PATCH v3 1/4] gpiolib: Check "gpio-ranges" before calling ->add_pin_ranges()

[Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>]

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 <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
 drivers/gpio/gpiolib.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 16858ef4dac1..49cfcc7510e1 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -533,6 +533,14 @@ 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);
 
-- 
2.39.0