On Thu, Dec 09, 2010 at 12:33:22PM +1100, Michael Ellerman wrote:

On Wed, 2010-12-08 at 15:01 -0600, Scott Wood wrote:

quoted

On Wed, 8 Dec 2010 11:29:44 -0800
Deepak Saxena [off-list ref] wrote:

quoted

We only return the next child if the device is available.

Signed-off-by: Hollis Blanchard <redacted>
Signed-off-by: Deepak Saxena <redacted>
---
 drivers/of/base.c |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/drivers/of/base.c b/drivers/of/base.c
index 5d269a4..81b2601 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c

@@ -321,6 +321,8 @@ struct device_node *of_get_next_parent(struct device_node *node)
  *
  *	Returns a node pointer with refcount incremented, use
  *	of_node_put() on it when done.
+ *
+ *	Does not return nodes marked unavailable by a status property.
  */
 struct device_node *of_get_next_child(const struct device_node *node,
 	struct device_node *prev)

@@ -330,7 +332,7 @@ struct device_node *of_get_next_child(const struct device_node *node,
 	read_lock(&devtree_lock);
 	next = prev ? prev->sibling : node->child;
 	for (; next; next = next->sibling)
-		if (of_node_get(next))
+		if (of_device_is_available(next) && of_node_get(next))
 			break;
 	of_node_put(prev);
 	read_unlock(&devtree_lock);

This seems like too low-level a place to put this.  Some code may know
how to un-disable a device in certain situations, or it may be part of
debug code trying to dump the whole device tree, etc.  Looking
further[1], I see a raw version of this function, but not other things
like of_find_compatible_node.

Yeah I agree. I think we'll eventually end up with __ versions of all or
lots of them. Not to mention there might be cases you've missed where
code expects to see unavailable nodes. The right approach is to add
_new_ routines that don't return unavailable nodes, and convert code
that you know wants to use them.

Actually, I don't think we really want these status-skipping
iterators at all.  The device tree iterators should give us the device
tree, as it is.  Those old-style drivers which seach for a node rather
than using the bus probing logic can keep individual checks of the
status property until they're converted to the new scheme.


-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
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