/* * sys.c - pseudo-bus for system 'devices' (cpus, PICs, timers, etc) * * Copyright (c) 2002-3 Patrick Mochel *               2002-3 Open Source Development Lab * * This file is released under the GPLv2 * * This exports a 'system' bus type. * By default, a 'sys' bus gets added to the root of the system. There will * always be core system devices. Devices can use sysdev_register() to * add themselves as children of the system bus. */ #include <linux/sysdev.h>#include <linux/err.h>#include <linux/module.h>#include <linux/kernel.h>#include <linux/init.h>#include <linux/string.h>#include <linux/pm.h>#include <linux/device.h>#include <linux/mutex.h>#include <linux/interrupt.h> #include "base.h" #define to_sysdev(k) container_of(k, struct sys_device, kobj)#define to_sysdev_attr(a) container_of(a, struct sysdev_attribute, attr)  static ssize_tsysdev_show(struct kobject *kobj, struct attribute *attr, char *buffer){	struct sys_device *sysdev = to_sysdev(kobj);	struct sysdev_attribute *sysdev_attr = to_sysdev_attr(attr); 	if (sysdev_attr->show)		return sysdev_attr->show(sysdev, sysdev_attr, buffer);	return -EIO;}  static ssize_tsysdev_store(struct kobject *kobj, struct attribute *attr,	     const char *buffer, size_t count){	struct sys_device *sysdev = to_sysdev(kobj);	struct sysdev_attribute *sysdev_attr = to_sysdev_attr(attr); 	if (sysdev_attr->store)		return sysdev_attr->store(sysdev, sysdev_attr, buffer, count);	return -EIO;} static const struct sysfs_ops sysfs_ops = {	.show	= sysdev_show,	.store	= sysdev_store,}; static struct kobj_type ktype_sysdev = {	.sysfs_ops	= &sysfs_ops,};  int sysdev_create_file(struct sys_device *s, struct sysdev_attribute *a){	return sysfs_create_file(&s->kobj, &a->attr);}  void sysdev_remove_file(struct sys_device *s, struct sysdev_attribute *a){	sysfs_remove_file(&s->kobj, &a->attr);} EXPORT_SYMBOL_GPL(sysdev_create_file);EXPORT_SYMBOL_GPL(sysdev_remove_file); #define to_sysdev_class(k) container_of(k, struct sysdev_class, kset.kobj)#define to_sysdev_class_attr(a) container_of(a, \	struct sysdev_class_attribute, attr) static ssize_t sysdev_class_show(struct kobject *kobj, struct attribute *attr,				 char *buffer){	struct sysdev_class *class = to_sysdev_class(kobj);	struct sysdev_class_attribute *class_attr = to_sysdev_class_attr(attr); 	if (class_attr->show)		return class_attr->show(class, class_attr, buffer);	return -EIO;} static ssize_t sysdev_class_store(struct kobject *kobj, struct attribute *attr,				  const char *buffer, size_t count){	struct sysdev_class *class = to_sysdev_class(kobj);	struct sysdev_class_attribute *class_attr = to_sysdev_class_attr(attr); 	if (class_attr->store)		return class_attr->store(class, class_attr, buffer, count);	return -EIO;} static const struct sysfs_ops sysfs_class_ops = {	.show	= sysdev_class_show,	.store	= sysdev_class_store,}; static struct kobj_type ktype_sysdev_class = {	.sysfs_ops	= &sysfs_class_ops,}; int sysdev_class_create_file(struct sysdev_class *c,			     struct sysdev_class_attribute *a){	return sysfs_create_file(&c->kset.kobj, &a->attr);}EXPORT_SYMBOL_GPL(sysdev_class_create_file); void sysdev_class_remove_file(struct sysdev_class *c,			      struct sysdev_class_attribute *a){	sysfs_remove_file(&c->kset.kobj, &a->attr);}EXPORT_SYMBOL_GPL(sysdev_class_remove_file); static struct kset *system_kset; int sysdev_class_register(struct sysdev_class *cls){	int retval; 	pr_debug("Registering sysdev class '%s'\n", cls->name); 	INIT_LIST_HEAD(&cls->drivers);	memset(&cls->kset.kobj, 0x00, sizeof(struct kobject));	cls->kset.kobj.parent = &system_kset->kobj;	cls->kset.kobj.ktype = &ktype_sysdev_class;	cls->kset.kobj.kset = system_kset; 	retval = kobject_set_name(&cls->kset.kobj, "%s", cls->name);	if (retval)		return retval; 	retval = kset_register(&cls->kset);	if (!retval && cls->attrs)		retval = sysfs_create_files(&cls->kset.kobj,					    (const struct attribute **)cls->attrs);	return retval;} void sysdev_class_unregister(struct sysdev_class *cls){	pr_debug("Unregistering sysdev class '%s'\n",		 kobject_name(&cls->kset.kobj));	if (cls->attrs)		sysfs_remove_files(&cls->kset.kobj,				   (const struct attribute **)cls->attrs);	kset_unregister(&cls->kset);} EXPORT_SYMBOL_GPL(sysdev_class_register);EXPORT_SYMBOL_GPL(sysdev_class_unregister); static DEFINE_MUTEX(sysdev_drivers_lock); /* * @dev != NULL means that we're unwinding because some drv->add() * failed for some reason. You need to grab sysdev_drivers_lock before * calling this. */static void __sysdev_driver_remove(struct sysdev_class *cls,				   struct sysdev_driver *drv,				   struct sys_device *from_dev){	struct sys_device *dev = from_dev; 	list_del_init(&drv->entry);	if (!cls)		return; 	if (!drv->remove)		goto kset_put; 	if (dev)		list_for_each_entry_continue_reverse(dev, &cls->kset.list,						     kobj.entry)			drv->remove(dev);	else		list_for_each_entry(dev, &cls->kset.list, kobj.entry)			drv->remove(dev); kset_put:	kset_put(&cls->kset);} /** *	sysdev_driver_register - Register auxiliary driver *	@cls:	Device class driver belongs to. *	@drv:	Driver. * *	@drv is inserted into @cls->drivers to be *	called on each operation on devices of that class. The refcount *	of @cls is incremented. */int sysdev_driver_register(struct sysdev_class *cls, struct sysdev_driver *drv){	struct sys_device *dev = NULL;	int err = 0; 	if (!cls) {		WARN(1, KERN_WARNING "sysdev: invalid class passed to %s!\n",			__func__);		return -EINVAL;	} 	/* Check whether this driver has already been added to a class. */	if (drv->entry.next && !list_empty(&drv->entry))		WARN(1, KERN_WARNING "sysdev: class %s: driver (%p) has already"			" been registered to a class, something is wrong, but "			"will forge on!\n", cls->name, drv); 	mutex_lock(&sysdev_drivers_lock);	if (cls && kset_get(&cls->kset)) {		list_add_tail(&drv->entry, &cls->drivers); 		/* If devices of this class already exist, tell the driver */		if (drv->add) {			list_for_each_entry(dev, &cls->kset.list, kobj.entry) {				err = drv->add(dev);				if (err)					goto unwind;			}		}	} else {		err = -EINVAL;		WARN(1, KERN_ERR "%s: invalid device class\n", __func__);	} 	goto unlock; unwind:	__sysdev_driver_remove(cls, drv, dev); unlock:	mutex_unlock(&sysdev_drivers_lock);	return err;} /** *	sysdev_driver_unregister - Remove an auxiliary driver. *	@cls:	Class driver belongs to. *	@drv:	Driver. */void sysdev_driver_unregister(struct sysdev_class *cls,			      struct sysdev_driver *drv){	mutex_lock(&sysdev_drivers_lock);	__sysdev_driver_remove(cls, drv, NULL);	mutex_unlock(&sysdev_drivers_lock);}EXPORT_SYMBOL_GPL(sysdev_driver_register);EXPORT_SYMBOL_GPL(sysdev_driver_unregister); /** *	sysdev_register - add a system device to the tree *	@sysdev:	device in question * */int sysdev_register(struct sys_device *sysdev){	int error;	struct sysdev_class *cls = sysdev->cls; 	if (!cls)		return -EINVAL; 	pr_debug("Registering sys device of class '%s'\n",		 kobject_name(&cls->kset.kobj)); 	/* initialize the kobject to 0, in case it had previously been used */	memset(&sysdev->kobj, 0x00, sizeof(struct kobject)); 	/* Make sure the kset is set */	sysdev->kobj.kset = &cls->kset; 	/* Register the object */	error = kobject_init_and_add(&sysdev->kobj, &ktype_sysdev, NULL,				     "%s%d", kobject_name(&cls->kset.kobj),				     sysdev->id); 	if (!error) {		struct sysdev_driver *drv; 		pr_debug("Registering sys device '%s'\n",			 kobject_name(&sysdev->kobj)); 		mutex_lock(&sysdev_drivers_lock);		/* Generic notification is implicit, because it's that		 * code that should have called us.		 */ 		/* Notify class auxiliary drivers */		list_for_each_entry(drv, &cls->drivers, entry) {			if (drv->add)				drv->add(sysdev);		}		mutex_unlock(&sysdev_drivers_lock);		kobject_uevent(&sysdev->kobj, KOBJ_ADD);	} 	return error;} void sysdev_unregister(struct sys_device *sysdev){	struct sysdev_driver *drv; 	mutex_lock(&sysdev_drivers_lock);	list_for_each_entry(drv, &sysdev->cls->drivers, entry) {		if (drv->remove)			drv->remove(sysdev);	}	mutex_unlock(&sysdev_drivers_lock); 	kobject_put(&sysdev->kobj);} EXPORT_SYMBOL_GPL(sysdev_register);EXPORT_SYMBOL_GPL(sysdev_unregister); int __init system_bus_init(void){	system_kset = kset_create_and_add("system", NULL, &devices_kset->kobj);	if (!system_kset)		return -ENOMEM;	return 0;} #define to_ext_attr(x) container_of(x, struct sysdev_ext_attribute, attr) ssize_t sysdev_store_ulong(struct sys_device *sysdev,			   struct sysdev_attribute *attr,			   const char *buf, size_t size){	struct sysdev_ext_attribute *ea = to_ext_attr(attr);	char *end;	unsigned long new = simple_strtoul(buf, &end, 0);	if (end == buf)		return -EINVAL;	*(unsigned long *)(ea->var) = new;	/* Always return full write size even if we didn't consume all */	return size;}EXPORT_SYMBOL_GPL(sysdev_store_ulong); ssize_t sysdev_show_ulong(struct sys_device *sysdev,			  struct sysdev_attribute *attr,			  char *buf){	struct sysdev_ext_attribute *ea = to_ext_attr(attr);	return snprintf(buf, PAGE_SIZE, "%lx\n", *(unsigned long *)(ea->var));}EXPORT_SYMBOL_GPL(sysdev_show_ulong); ssize_t sysdev_store_int(struct sys_device *sysdev,			   struct sysdev_attribute *attr,			   const char *buf, size_t size){	struct sysdev_ext_attribute *ea = to_ext_attr(attr);	char *end;	long new = simple_strtol(buf, &end, 0);	if (end == buf || new > INT_MAX || new < INT_MIN)		return -EINVAL;	*(int *)(ea->var) = new;	/* Always return full write size even if we didn't consume all */	return size;}EXPORT_SYMBOL_GPL(sysdev_store_int); ssize_t sysdev_show_int(struct sys_device *sysdev,			  struct sysdev_attribute *attr,			  char *buf){	struct sysdev_ext_attribute *ea = to_ext_attr(attr);	return snprintf(buf, PAGE_SIZE, "%d\n", *(int *)(ea->var));}EXPORT_SYMBOL_GPL(sysdev_show_int);