Driver core: fix deprectated sysfs structure for nested class devices

Nested class devices used to have 'device' symlink point to a real
(physical) device instead of a parent class device.  When converting
subsystems to struct device we need to keep doing what class devices did if
CONFIG_SYSFS_DEPRECATED is Y, otherwise parts of udev break.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Acked-by: Greg KH <greg@kroah.com>
Tested-by: Anssi Hannula <anssi.hannula@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/base/core.c b/drivers/base/core.c
index e6738bcbe5a9b2da343e5d20a67b51a6b28545ee..6de33d7a29ba989194cd6fa4f0148cc702acebed 100644 (file)
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -679,14 +679,26 @@ static int device_add_class_symlinks(struct device *dev)
                        goto out_subsys;
        }
        if (dev->parent) {
-               error = sysfs_create_link(&dev->kobj, &dev->parent->kobj,
-                                         "device");
-               if (error)
-                       goto out_busid;
 #ifdef CONFIG_SYSFS_DEPRECATED
                {
-                       char * class_name = make_class_name(dev->class->name,
-                                                               &dev->kobj);
+                       struct device *parent = dev->parent;
+                       char *class_name;
+
+                       /*
+                        * In old sysfs stacked class devices had 'device'
+                        * link pointing to real device instead of parent
+                        */
+                       while (parent->class && !parent->bus && parent->parent)
+                               parent = parent->parent;
+
+                       error = sysfs_create_link(&dev->kobj,
+                                                 &parent->kobj,
+                                                 "device");
+                       if (error)
+                               goto out_busid;
+
+                       class_name = make_class_name(dev->class->name,
+                                                       &dev->kobj);
                        if (class_name)
                                error = sysfs_create_link(&dev->parent->kobj,
                                                        &dev->kobj, class_name);
@@ -694,6 +706,11 @@ static int device_add_class_symlinks(struct device *dev)
                        if (error)
                                goto out_device;
                }
+#else
+               error = sysfs_create_link(&dev->kobj, &dev->parent->kobj,
+                                         "device");
+               if (error)
+                       goto out_busid;
 #endif
        }
        return 0;