sound_class = class_simple_create(THIS_MODULE, "sound");
sound_class = class_create(THIS_MODULE, "sound");
static int __init init_soundcore(void){	if (register_chrdev(SOUND_MAJOR, "sound", &soundcore_fops)==-1) {		printk(KERN_ERR "soundcore: sound device already in use.\n");		return -EBUSY;	}	devfs_mk_dir ("sound");	sound_class = class_simple_create(THIS_MODULE, "sound");	if (IS_ERR(sound_class))		return PTR_ERR(sound_class);	return 0;}