Driver core: Fix device_move() vs. dpm list ordering, v2

dpm_list currently relies on the fact that child devices will
be registered after their parents to get a correct suspend
order. Using device_move() however destroys this assumption, as
an already registered device may be moved under a newly registered
one.

This patch adds a new argument to device_move(), allowing callers
to specify how dpm_list should be adapted.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 18 insertions, 1 deletions

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 95c67ffd71da..e73c92d13a23 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -1561,8 +1561,10 @@ out:
  * device_move - moves a device to a new parent
  * @dev: the pointer to the struct device to be moved
  * @new_parent: the new parent of the device (can by NULL)
+ * @dpm_order: how to reorder the dpm_list
  */
-int device_move(struct device *dev, struct device *new_parent)
+int device_move(struct device *dev, struct device *new_parent,
+                enum dpm_order dpm_order)
 {
         int error;
         struct device *old_parent;
@@ -1572,6 +1574,7 @@ int device_move(struct device *dev, struct device *new_parent)
         if (!dev)
                 return -EINVAL;
 
+        device_pm_lock();
         new_parent = get_device(new_parent);
         new_parent_kobj = get_device_parent(dev, new_parent);
 
@@ -1613,9 +1616,23 @@ int device_move(struct device *dev, struct device *new_parent)
                 put_device(new_parent);
                 goto out;
         }
+        switch (dpm_order) {
+        case DPM_ORDER_NONE:
+                break;
+        case DPM_ORDER_DEV_AFTER_PARENT:
+                device_pm_move_after(dev, new_parent);
+                break;
+        case DPM_ORDER_PARENT_BEFORE_DEV:
+                device_pm_move_before(new_parent, dev);
+                break;
+        case DPM_ORDER_DEV_LAST:
+                device_pm_move_last(dev);
+                break;
+        }
 out_put:
         put_device(old_parent);
 out:
+        device_pm_unlock();
         put_device(dev);
         return error;
 }