gpio: gpio-mm-lantiq: Use of_mm_gpiochip_remove

Since d621e8bae5 (Create of_mm_gpiochip_remove), there is a
counterpart for of_mm_gpiochip_add.

This patch implements the remove function of the driver making use of
it.

Cc: Alexandre Courbot <gnurou@gmail.com>
Cc: John Crispin <blogic@openwrt.org>
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpio-mm-lantiq.c

@@ -111,6 +111,8 @@ static int ltq_mm_probe(struct platform_device *pdev)
 	if (!chip)
 		return -ENOMEM;
 
+	platform_set_drvdata(pdev, chip);
+
 	chip->mmchip.gc.ngpio = 16;
 	chip->mmchip.gc.direction_output = ltq_mm_dir_out;
 	chip->mmchip.gc.set = ltq_mm_set;
@@ -123,6 +125,15 @@ static int ltq_mm_probe(struct platform_device *pdev)
 	return of_mm_gpiochip_add(pdev->dev.of_node, &chip->mmchip);
 }
 
+static int ltq_mm_remove(struct platform_device *pdev)
+{
+	struct ltq_mm *chip = platform_get_drvdata(pdev);
+
+	of_mm_gpiochip_remove(&chip->mmchip);
+
+	return 0;
+}
+
 static const struct of_device_id ltq_mm_match[] = {
 	{ .compatible = "lantiq,gpio-mm" },
 	{},
@@ -131,6 +142,7 @@ MODULE_DEVICE_TABLE(of, ltq_mm_match);
 
 static struct platform_driver ltq_mm_driver = {
 	.probe = ltq_mm_probe,
+	.remove = ltq_mm_remove,
 	.driver = {
 		.name = "gpio-mm-ltq",
 		.of_match_table = ltq_mm_match,
@@ -143,3 +155,9 @@ static int __init ltq_mm_init(void)
 }
 
 subsys_initcall(ltq_mm_init);
+
+static void __exit ltq_mm_exit(void)
+{
+	platform_driver_unregister(&ltq_mm_driver);
+}
+module_exit(ltq_mm_exit);