Unregister and destroy a cdev
void __unregister_chrdev(unsigned int major, unsigned int baseminor, unsigned int count, const char * name);
major
major device number
baseminor
first of the range of minor numbers
count
the number of minor numbers this cdev is occupying
name
name of this range of devices
Unregister and destroy the cdev occupying the region described by major, baseminor and count. This function undoes what __register_chrdev did.