devfs_register_chrdev -- Optionally register a conventional character driver.
(unsigned int major, const char * name, struct file_operations * fops);
The major number for the driver.
The name of the driver (as seen in /proc/devices).
The &file_operations structure pointer.
This function will register a character driver provided the "devfs=only"
option was not provided at boot time.
Returns 0 on success, else a negative error code on failure.