[PATCH] Driver core: add generic "subsystem" link to all devices
Like the SUBSYTEM= key we find in the environment of the uevent, this
creates a generic "subsystem" link in sysfs for every device. Userspace
usually doesn't care at all if its a "class" or a "bus" device. This
provides an unified way to determine the subsytem of a device, regardless
of the way the driver core has created it.
Signed-off-by: Kay Sievers <kay.sievers@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/base/core.c b/drivers/base/core.c
index 252cf40..cc8bb97 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -319,9 +319,12 @@
dev->devt_attr = attr;
}
- if (dev->class)
+ if (dev->class) {
+ sysfs_create_link(&dev->kobj, &dev->class->subsys.kset.kobj,
+ "subsystem");
sysfs_create_link(&dev->class->subsys.kset.kobj, &dev->kobj,
dev->bus_id);
+ }
if ((error = device_pm_add(dev)))
goto PMError;
@@ -422,8 +425,10 @@
klist_del(&dev->knode_parent);
if (dev->devt_attr)
device_remove_file(dev, dev->devt_attr);
- if (dev->class)
+ if (dev->class) {
+ sysfs_remove_link(&dev->kobj, "subsystem");
sysfs_remove_link(&dev->class->subsys.kset.kobj, dev->bus_id);
+ }
device_remove_file(dev, &dev->uevent_attr);
/* Notify the platform of the removal, in case they