diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/base/class.c | 2 | ||||
| -rw-r--r-- | drivers/base/core.c | 82 |
2 files changed, 66 insertions, 18 deletions
diff --git a/drivers/base/class.c b/drivers/base/class.c index d5968128be2b..80bbb2074636 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -145,6 +145,7 @@ int class_register(struct class * cls) INIT_LIST_HEAD(&cls->children); INIT_LIST_HEAD(&cls->devices); INIT_LIST_HEAD(&cls->interfaces); + kset_init(&cls->class_dirs); init_MUTEX(&cls->sem); error = kobject_set_name(&cls->subsys.kset.kobj, "%s", cls->name); if (error) @@ -163,7 +164,6 @@ int class_register(struct class * cls) void class_unregister(struct class * cls) { pr_debug("device class '%s': unregistering\n", cls->name); - kobject_unregister(cls->virtual_dir); remove_class_attrs(cls); subsystem_unregister(&cls->subsys); } diff --git a/drivers/base/core.c b/drivers/base/core.c index db3a151be4a1..658eae5dacda 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -477,34 +477,58 @@ static struct kobject * get_device_parent(struct device *dev, return NULL; } #else -static struct kobject * virtual_device_parent(struct device *dev) +static struct kobject *virtual_device_parent(struct device *dev) { - if (!dev->class) - return ERR_PTR(-ENODEV); - - if (!dev->class->virtual_dir) { - static struct kobject *virtual_dir = NULL; + static struct kobject *virtual_dir = NULL; - if (!virtual_dir) - virtual_dir = kobject_add_dir(&devices_subsys.kset.kobj, "virtual"); - dev->class->virtual_dir = kobject_add_dir(virtual_dir, dev->class->name); - } + if (!virtual_dir) + virtual_dir = kobject_add_dir(&devices_subsys.kset.kobj, "virtual"); - return dev->class->virtual_dir; + return virtual_dir; } static struct kobject * get_device_parent(struct device *dev, struct device *parent) { - /* if this is a class device, and has no parent, create one */ - if ((dev->class) && (parent == NULL)) { - return virtual_device_parent(dev); - } else if (parent) + if (dev->class) { + struct kobject *kobj = NULL; + struct kobject *parent_kobj; + struct kobject *k; + + /* + * If we have no parent, we live in "virtual". + * Class-devices with a bus-device as parent, live + * in a class-directory to prevent namespace collisions. + */ + if (parent == NULL) + parent_kobj = virtual_device_parent(dev); + else if (parent->class) + return &parent->kobj; + else + parent_kobj = &parent->kobj; + + /* find our class-directory at the parent and reference it */ + spin_lock(&dev->class->class_dirs.list_lock); + list_for_each_entry(k, &dev->class->class_dirs.list, entry) + if (k->parent == parent_kobj) { + kobj = kobject_get(k); + break; + } + spin_unlock(&dev->class->class_dirs.list_lock); + if (kobj) + return kobj; + + /* or create a new class-directory at the parent device */ + return kobject_kset_add_dir(&dev->class->class_dirs, + parent_kobj, dev->class->name); + } + + if (parent) return &parent->kobj; return NULL; } - #endif + static int setup_parent(struct device *dev, struct device *parent) { struct kobject *kobj; @@ -541,7 +565,6 @@ int device_add(struct device *dev) pr_debug("DEV: registering device: ID = '%s'\n", dev->bus_id); parent = get_device(dev->parent); - error = setup_parent(dev, parent); if (error) goto Error; @@ -787,6 +810,31 @@ void device_del(struct device * dev) /* remove the device from the class list */ list_del_init(&dev->node); up(&dev->class->sem); + + /* If we live in a parent class-directory, unreference it */ + if (dev->kobj.parent->kset == &dev->class->class_dirs) { + struct device *d; + int other = 0; + + /* + * if we are the last child of our class, delete + * our class-directory at this parent + */ + down(&dev->class->sem); + list_for_each_entry(d, &dev->class->devices, node) { + if (d == dev) + continue; + if (d->kobj.parent == dev->kobj.parent) { + other = 1; + break; + } + } + if (!other) + kobject_del(dev->kobj.parent); + + kobject_put(dev->kobj.parent); + up(&dev->class->sem); + } } device_remove_file(dev, &dev->uevent_attr); device_remove_groups(dev); |