gpiolib: Introduce acpi_gpio_dev_init() and call it from core

In the ACPI case we may use the firmware node in the similar way
as it's done for OF case. We may use that fwnode for other purposes
in the future.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>

drivers/gpio/gpiolib-acpi.c

@@ -1291,6 +1291,13 @@ void acpi_gpiochip_remove(struct gpio_chip *chip)
 	kfree(acpi_gpio);
 }
 
+void acpi_gpio_dev_init(struct gpio_chip *gc, struct gpio_device *gdev)
+{
+	/* Set default fwnode to parent's one if present */
+	if (gc->parent)
+		ACPI_COMPANION_SET(&gdev->dev, ACPI_COMPANION(gc->parent));
+}
+
 static int acpi_gpio_package_count(const union acpi_object *obj)
 {
 	const union acpi_object *element = obj->package.elements;

drivers/gpio/gpiolib-acpi.h

@@ -36,6 +36,8 @@ struct acpi_gpio_info {
 void acpi_gpiochip_add(struct gpio_chip *chip);
 void acpi_gpiochip_remove(struct gpio_chip *chip);
 
+void acpi_gpio_dev_init(struct gpio_chip *gc, struct gpio_device *gdev);
+
 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip);
 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip);
 
@@ -58,6 +60,8 @@ int acpi_gpio_count(struct device *dev, const char *con_id);
 static inline void acpi_gpiochip_add(struct gpio_chip *chip) { }
 static inline void acpi_gpiochip_remove(struct gpio_chip *chip) { }
 
+static inline void acpi_gpio_dev_init(struct gpio_chip *gc, struct gpio_device *gdev) { }
+
 static inline void
 acpi_gpiochip_request_interrupts(struct gpio_chip *chip) { }
 

drivers/gpio/gpiolib.c

@@ -591,6 +591,7 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
 	gc->gpiodev = gdev;
 
 	of_gpio_dev_init(gc, gdev);
+	acpi_gpio_dev_init(gc, gdev);
 
 	/*
 	 * Assign fwnode depending on the result of the previous calls,