gpiolib: cleanup chained handler and data

Clean up chained handler and handler data if they were set by
gpiochip_set_chained_irqchip().

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpiolib.c

@@ -443,6 +443,8 @@ void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip,
 		 */
 		irq_set_handler_data(parent_irq, gpiochip);
 		irq_set_chained_handler(parent_irq, parent_handler);
+
+		gpiochip->irq_parent = parent_irq;
 	}
 
 	/* Set the parent IRQ for all affected IRQs */
@@ -551,6 +553,11 @@ static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip)
 
 	acpi_gpiochip_free_interrupts(gpiochip);
 
+	if (gpiochip->irq_parent) {
+		irq_set_chained_handler(gpiochip->irq_parent, NULL);
+		irq_set_handler_data(gpiochip->irq_parent, NULL);
+	}
+
 	/* Remove all IRQ mappings and delete the domain */
 	if (gpiochip->irqdomain) {
 		for (offset = 0; offset < gpiochip->ngpio; offset++)

include/linux/gpio/driver.h

@@ -121,6 +121,7 @@ struct gpio_chip {
 	unsigned int		irq_base;
 	irq_flow_handler_t	irq_handler;
 	unsigned int		irq_default_type;
+	int			irq_parent;
 #endif
 
 #if defined(CONFIG_OF_GPIO)