3  * class.c - basic device class management
11 #include <linux/device/class.h>
23 /* /sys/class */
29  * class_to_subsys - Turn a struct class into a struct subsys_private
31  * @class: pointer to the struct bus_type to look up
34  * the external struct class pointer.  This function walks the list of
36  * internal struct subsys_private that relates to that class.
42 struct subsys_private *class_to_subsys(const struct class *class)  in class_to_subsys()  argument
47 	if (!class || !class_kset)  in class_to_subsys()
59 		if (sp->class == class)  in class_to_subsys()
77 		ret = class_attr->show(cp->class, class_attr, buf);  in class_attr_show()
89 		ret = class_attr->store(cp->class, class_attr, buf, count);  in class_attr_store()
96 	const struct class *class = cp->class;  in class_release()  local
98 	pr_debug("class '%s': release.\n", class->name);  in class_release()
100 	if (class->class_release)  in class_release()
101 		class->class_release(class);  in class_release()
103 		pr_debug("class '%s' does not have a release() function, "  in class_release()
104 			 "be careful\n", class->name);  in class_release()
113 	const struct class *class = cp->class;  in class_child_ns_type()  local
115 	return class->ns_type;  in class_child_ns_type()
129 int class_create_file_ns(const struct class *cls, const struct class_attribute *attr,  in class_create_file_ns()
145 void class_remove_file_ns(const struct class *cls, const struct class_attribute *attr,  in class_remove_file_ns()
178 int class_register(const struct class *cls)  in class_register()
184 	pr_debug("device class '%s': registering\n", cls->name);  in class_register()
187 		pr_err("%s: class '%s' does not have namespace\n",  in class_register()
192 		pr_err("%s: class '%s' does not have ns_type\n",  in class_register()
212 	cp->class = cls;  in class_register()
233 void class_unregister(const struct class *cls)  in class_unregister()
240 	pr_debug("device class '%s': unregistering\n", cls->name);  in class_unregister()
248 static void class_create_release(const struct class *cls)  in class_create_release()
255  * class_create - create a struct class structure
256  * @name: pointer to a string for the name of this class.
258  * This is used to create a struct class pointer that can then be used
261  * Returns &struct class pointer on success, or ERR_PTR() on error.
266 struct class *class_create(const char *name)  in class_create()
268 	struct class *cls;  in class_create()
293  * class_destroy - destroys a struct class structure
294  * @cls: pointer to the struct class that is to be destroyed
299 void class_destroy(const struct class *cls)  in class_destroy()
309  * class_dev_iter_init - initialize class device iterator
310  * @iter: class iterator to initialize
311  * @class: the class we wanna iterate over
315  * Initialize class iterator @iter such that it iterates over devices
316  * of @class.  If @start is set, the list iteration will start there,
320 void class_dev_iter_init(struct class_dev_iter *iter, const struct class *class,  in class_dev_iter_init()  argument
323 	struct subsys_private *sp = class_to_subsys(class);  in class_dev_iter_init()
328 		pr_crit("%s: class %p was not registered yet\n",  in class_dev_iter_init()
329 			__func__, class);  in class_dev_iter_init()
343  * @iter: class iterator to proceed
351  * calling back into class code.
374  * @iter: class iterator to finish
388  * @class: the class we're iterating
393  * Iterate over @class's list of devices, and call @fn for each,
401  * @fn is allowed to do anything including calling back into class
404 int class_for_each_device(const struct class *class, const struct device *start,  in class_for_each_device()  argument
407 	struct subsys_private *sp = class_to_subsys(class);  in class_for_each_device()
412 	if (!class)  in class_for_each_device()
415 		WARN(1, "%s called for class '%s' before it was registered",  in class_for_each_device()
416 		     __func__, class->name);  in class_for_each_device()
420 	class_dev_iter_init(&iter, class, start, NULL);  in class_for_each_device()
435  * @class: the class we're iterating
450  * @match is allowed to do anything including calling back into class
453 struct device *class_find_device(const struct class *class, const struct device *start,  in class_find_device()  argument
456 	struct subsys_private *sp = class_to_subsys(class);  in class_find_device()
460 	if (!class)  in class_find_device()
463 		WARN(1, "%s called for class '%s' before it was registered",  in class_find_device()
464 		     __func__, class->name);  in class_find_device()
468 	class_dev_iter_init(&iter, class, start, NULL);  in class_find_device()
485 	const struct class *parent;  in class_interface_register()
489 	if (!class_intf || !class_intf->class)  in class_interface_register()
492 	parent = class_intf->class;  in class_interface_register()
519 	const struct class *parent = class_intf->class;  in class_interface_unregister()
550 ssize_t show_class_attr_string(const struct class *class,  in show_class_attr_string()  argument
566  * class_compat_register - register a compatibility class
567  * @name: the name of the class
569  * Compatibility class are meant as a temporary user-space compatibility
570  * workaround when converting a family of class devices to a bus devices.
589  * class_compat_unregister - unregister a compatibility class
590  * @cls: the class to unregister
600  * class_compat_create_link - create a compatibility class device link to
602  * @cls: the compatibility class
612  * class_compat_remove_link - remove a compatibility class device link to
614  * @cls: the compatibility class
624  * class_is_registered - determine if at this moment in time, a class is
626  * @class: the class to check
628  * Returns a boolean to state if the class is registered in the driver core
631  * to determine if the specific class has been registered yet or not).
635 bool class_is_registered(const struct class *class)  in class_is_registered()  argument
637 	struct subsys_private *sp = class_to_subsys(class);  in class_is_registered()
650 	class_kset = kset_create_and_add("class", NULL, NULL);  in classes_init()