misc: hpilo: make ilo_class a static const structure

Now that the driver core allows for struct class to be in read-only
memory, move the ilo_class structure to be declared at build time
placing it into read-only memory, instead of having to be dynamically
allocated at boot time.

Suggested-by: Greg Kroah-Hartman <[e-mail]>
Signed-off-by: Ivan Orlov <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/misc/hpilo.c

···
 #include <linux/slab.h>
 #include "hpilo.h"
 
-static struct class *ilo_class;
+static const struct class ilo_class = {
+	.name = "iLO",
+};
 static unsigned int ilo_major;
 static unsigned int max_ccb = 16;
 static char ilo_hwdev[MAX_ILO_DEV];
···
 
 	minor = MINOR(ilo_hw->cdev.dev);
 	for (i = minor; i < minor + max_ccb; i++)
-		device_destroy(ilo_class, MKDEV(ilo_major, i));
+		device_destroy(&ilo_class, MKDEV(ilo_major, i));
 
 	cdev_del(&ilo_hw->cdev);
 	ilo_disable_interrupts(ilo_hw);
···
 
 	for (minor = 0 ; minor < max_ccb; minor++) {
 		struct device *dev;
-		dev = device_create(ilo_class, &pdev->dev,
+		dev = device_create(&ilo_class, &pdev->dev,
 				    MKDEV(ilo_major, minor), NULL,
 				    "hpilo!d%dccb%d", devnum, minor);
 		if (IS_ERR(dev))
···
 	int error;
 	dev_t dev;
 
-	ilo_class = class_create("iLO");
-	if (IS_ERR(ilo_class)) {
-		error = PTR_ERR(ilo_class);
+	error = class_register(&ilo_class);
+	if (error)
 		goto out;
-	}
 
 	error = alloc_chrdev_region(&dev, 0, MAX_OPEN, ILO_NAME);
 	if (error)
···
 chr_remove:
 	unregister_chrdev_region(dev, MAX_OPEN);
 class_destroy:
-	class_destroy(ilo_class);
+	class_unregister(&ilo_class);
 out:
 	return error;
 }
···
 {
 	pci_unregister_driver(&ilo_driver);
 	unregister_chrdev_region(MKDEV(ilo_major, 0), MAX_OPEN);
-	class_destroy(ilo_class);
+	class_unregister(&ilo_class);
 }
 
 MODULE_VERSION("1.5.0");