diff options
Diffstat (limited to 'drivers/base/core.c')
| -rw-r--r-- | drivers/base/core.c | 83 |
1 files changed, 82 insertions, 1 deletions
diff --git a/drivers/base/core.c b/drivers/base/core.c index ee0a51a3a41d..be9aba4dc2fb 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -27,6 +27,9 @@ int (*platform_notify)(struct device *dev) = NULL; int (*platform_notify_remove)(struct device *dev) = NULL; +static struct kobject *dev_kobj; +struct kobject *sysfs_dev_char_kobj; +struct kobject *sysfs_dev_block_kobj; #ifdef CONFIG_BLOCK static inline int device_is_not_partition(struct device *dev) @@ -776,6 +779,54 @@ int dev_set_name(struct device *dev, const char *fmt, ...) EXPORT_SYMBOL_GPL(dev_set_name); /** + * device_to_dev_kobj - select a /sys/dev/ directory for the device + * @dev: device + * + * By default we select char/ for new entries. Setting class->dev_obj + * to NULL prevents an entry from being created. class->dev_kobj must + * be set (or cleared) before any devices are registered to the class + * otherwise device_create_sys_dev_entry() and + * device_remove_sys_dev_entry() will disagree about the the presence + * of the link. + */ +static struct kobject *device_to_dev_kobj(struct device *dev) +{ + struct kobject *kobj; + + if (dev->class) + kobj = dev->class->dev_kobj; + else + kobj = sysfs_dev_char_kobj; + + return kobj; +} + +static int device_create_sys_dev_entry(struct device *dev) +{ + struct kobject *kobj = device_to_dev_kobj(dev); + int error = 0; + char devt_str[15]; + + if (kobj) { + format_dev_t(devt_str, dev->devt); + error = sysfs_create_link(kobj, &dev->kobj, devt_str); + } + + return error; +} + +static void device_remove_sys_dev_entry(struct device *dev) +{ + struct kobject *kobj = device_to_dev_kobj(dev); + char devt_str[15]; + + if (kobj) { + format_dev_t(devt_str, dev->devt); + sysfs_remove_link(kobj, devt_str); + } +} + +/** * device_add - add device to device hierarchy. * @dev: device. * @@ -829,6 +880,10 @@ int device_add(struct device *dev) error = device_create_file(dev, &devt_attr); if (error) goto ueventattrError; + + error = device_create_sys_dev_entry(dev); + if (error) + goto devtattrError; } error = device_add_class_symlinks(dev); @@ -873,6 +928,9 @@ int device_add(struct device *dev) device_remove_class_symlinks(dev); SymlinkError: if (MAJOR(dev->devt)) + device_remove_sys_dev_entry(dev); + devtattrError: + if (MAJOR(dev->devt)) device_remove_file(dev, &devt_attr); ueventattrError: device_remove_file(dev, &uevent_attr); @@ -948,8 +1006,10 @@ void device_del(struct device *dev) device_pm_remove(dev); if (parent) klist_del(&dev->knode_parent); - if (MAJOR(dev->devt)) + if (MAJOR(dev->devt)) { + device_remove_sys_dev_entry(dev); device_remove_file(dev, &devt_attr); + } if (dev->class) { device_remove_class_symlinks(dev); @@ -1074,7 +1134,25 @@ int __init devices_init(void) devices_kset = kset_create_and_add("devices", &device_uevent_ops, NULL); if (!devices_kset) return -ENOMEM; + dev_kobj = kobject_create_and_add("dev", NULL); + if (!dev_kobj) + goto dev_kobj_err; + sysfs_dev_block_kobj = kobject_create_and_add("block", dev_kobj); + if (!sysfs_dev_block_kobj) + goto block_kobj_err; + sysfs_dev_char_kobj = kobject_create_and_add("char", dev_kobj); + if (!sysfs_dev_char_kobj) + goto char_kobj_err; + return 0; + + char_kobj_err: + kobject_put(sysfs_dev_block_kobj); + block_kobj_err: + kobject_put(dev_kobj); + dev_kobj_err: + kset_unregister(devices_kset); + return -ENOMEM; } EXPORT_SYMBOL_GPL(device_for_each_child); @@ -1447,4 +1525,7 @@ void device_shutdown(void) dev->driver->shutdown(dev); } } + kobject_put(sysfs_dev_char_kobj); + kobject_put(sysfs_dev_block_kobj); + kobject_put(dev_kobj); } |