gpiolib: Add GPIOCHIP_NAME definition

The string literal "gpiochip" is used in several places.
Add a definition for it, and use it everywhere, to make sure everything
stays in sync.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20191127084253.16356-2-geert+renesas@glider.beReviewed-by: Ulrich Hecht <uli+renesas@fpond.eu>
Reviewed-by: Eugeniu Rosca <erosca@de.adit-jv.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpiolib-sysfs.c

@@ -762,10 +762,9 @@ int gpiochip_sysfs_register(struct gpio_device *gdev)
 		parent = &gdev->dev;
 
 	/* use chip->base for the ID; it's already known to be unique */
-	dev = device_create_with_groups(&gpio_class, parent,
-					MKDEV(0, 0),
-					chip, gpiochip_groups,
-					"gpiochip%d", chip->base);
+	dev = device_create_with_groups(&gpio_class, parent, MKDEV(0, 0), chip,
+					gpiochip_groups, GPIOCHIP_NAME "%d",
+					chip->base);
 	if (IS_ERR(dev))
 		return PTR_ERR(dev);
 

drivers/gpio/gpiolib.c

@@ -1419,7 +1419,7 @@ int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
 		ret = gdev->id;
 		goto err_free_gdev;
 	}
-	dev_set_name(&gdev->dev, "gpiochip%d", gdev->id);
+	dev_set_name(&gdev->dev, GPIOCHIP_NAME "%d", gdev->id);
 	device_initialize(&gdev->dev);
 	dev_set_drvdata(&gdev->dev, gdev);
 	if (chip->parent && chip->parent->driver)
@@ -5104,7 +5104,7 @@ static int __init gpiolib_dev_init(void)
 		return ret;
 	}
 
-	ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, "gpiochip");
+	ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, GPIOCHIP_NAME);
 	if (ret < 0) {
 		pr_err("gpiolib: failed to allocate char dev region\n");
 		bus_unregister(&gpio_bus_type);

drivers/gpio/gpiolib.h

@@ -16,6 +16,8 @@
 #include <linux/module.h>
 #include <linux/cdev.h>
 
+#define GPIOCHIP_NAME	"gpiochip"
+
 /**
  * struct gpio_device - internal state container for GPIO devices
  * @id: numerical ID number for the GPIO chip