Then, now that your structure is ready, add it to the system:
int cdev_add(
struct cdev *p, /* Character device structure */
dev_t dev, /* Starting device major / minor number */
unsigned count); /* Number of devices */
After this function call, the kernel knows the association between the major/minor numbers and the file operations. Your device is ready to be used!
Example (continued):
if (cdev_add(&acme_cdev, acme_dev, acme_count)) {
printk (KERN_ERR “Char driver registration failed\n”);
...