15 #include <linux/major.h>
37 	unsigned int major;  member
45 static inline int major_to_index(unsigned major)  in major_to_index()  argument
47 	return major % CHRDEV_MAJOR_HASH_SIZE;  in major_to_index()
58 		if (cd->major == offset)  in chrdev_show()
59 			seq_printf(f, "%3d %s\n", cd->major, cd->name);  in chrdev_show()
79 			if (cd->major == i)  in find_dynamic_major()
90  * Register a single major with a specified minor range.
92  * If major == 0 this function will dynamically allocate an unused major.
93  * If major > 0 this function will attempt to reserve the range of minors
94  * with given major.
98 __register_chrdev_region(unsigned int major, unsigned int baseminor,  in __register_chrdev_region()  argument
106 	if (major >= CHRDEV_MAJOR_MAX) {  in __register_chrdev_region()
107 		pr_err("CHRDEV \"%s\" major requested (%u) is greater than the maximum (%u)\n",  in __register_chrdev_region()
108 		       name, major, CHRDEV_MAJOR_MAX-1);  in __register_chrdev_region()
113 …"%s\" minor range requested (%u-%u) is out of range of maximum range (%u-%u) for a single major\n",  in __register_chrdev_region()
124 	if (major == 0) {  in __register_chrdev_region()
131 		major = ret;  in __register_chrdev_region()
135 	i = major_to_index(major);  in __register_chrdev_region()
137 		if (curr->major < major)  in __register_chrdev_region()
140 		if (curr->major > major)  in __register_chrdev_region()
152 	cd->major = major;  in __register_chrdev_region()
169 __unregister_chrdev_region(unsigned major, unsigned baseminor, int minorct)  in __unregister_chrdev_region()  argument
172 	int i = major_to_index(major);  in __unregister_chrdev_region()
176 		if ((*cp)->major == major &&  in __unregister_chrdev_region()
191  *        the major number.
204 		next = MKDEV(MAJOR(n)+1, 0);  in register_chrdev_region()
207 		cd = __register_chrdev_region(MAJOR(n), MINOR(n),  in register_chrdev_region()
216 		next = MKDEV(MAJOR(n)+1, 0);  in register_chrdev_region()
217 		kfree(__unregister_chrdev_region(MAJOR(n), MINOR(n), next - n));  in register_chrdev_region()
229  * Allocates a range of char device numbers.  The major number will be
240 	*dev = MKDEV(cd->major, cd->baseminor);  in alloc_chrdev_region()
246  * @major: major device number or 0 for dynamic allocation
252  * If @major == 0 this functions will dynamically allocate a major and return
255  * If @major > 0 this function will attempt to reserve a device with the given
256  * major number and will return zero on success.
265 int __register_chrdev(unsigned int major, unsigned int baseminor,  in __register_chrdev()  argument
273 	cd = __register_chrdev_region(major, baseminor, count, name);  in __register_chrdev()
285 	err = cdev_add(cdev, MKDEV(cd->major, baseminor), count);  in __register_chrdev()
291 	return major ? 0 : cd->major;  in __register_chrdev()
295 	kfree(__unregister_chrdev_region(cd->major, baseminor, count));  in __register_chrdev()
314 		next = MKDEV(MAJOR(n)+1, 0);  in unregister_chrdev_region()
317 		kfree(__unregister_chrdev_region(MAJOR(n), MINOR(n), next - n));  in unregister_chrdev_region()
323  * @major: major device number
329  * @major, @baseminor and @count.  This function undoes what
332 void __unregister_chrdev(unsigned int major, unsigned int baseminor,  in __unregister_chrdev()  argument
337 	cd = __unregister_chrdev_region(major, baseminor, count);  in __unregister_chrdev()
665 	if (request_module("char-major-%d-%d", MAJOR(dev), MINOR(dev)) > 0)  in base_probe()
667 		request_module("char-major-%d", MAJOR(dev));  in base_probe()