diff options
| author | Johan Hovold <johan@kernel.org> | 2018-08-27 10:21:45 +0200 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2019-02-11 17:53:40 +0000 |
| commit | 6c4c6f8946efaafb2f3840c045eccfdfdff1a0fa (patch) | |
| tree | 9dd535677153bfa55890add36985fbf5cebfb17b /include | |
| parent | 400a7bc7c9218305737ca4d411a8cdc339d94f15 (diff) | |
of: add helper to lookup compatible child node
commit 36156f9241cb0f9e37d998052873ca7501ad4b36 upstream.
Add of_get_compatible_child() helper that can be used to lookup
compatible child nodes.
Several drivers currently use of_find_compatible_node() to lookup child
nodes while failing to notice that the of_find_ functions search the
entire tree depth-first (from a given start node) and therefore can
match unrelated nodes. The fact that these functions also drop a
reference to the node they start searching from (e.g. the parent node)
is typically also overlooked, something which can lead to use-after-free
bugs.
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/of.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/include/linux/of.h b/include/linux/of.h index 0c220cf91e92..15e6a340c1bd 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -237,6 +237,8 @@ extern struct device_node *of_get_next_child(const struct device_node *node, extern struct device_node *of_get_next_available_child( const struct device_node *node, struct device_node *prev); +extern struct device_node *of_get_compatible_child(const struct device_node *parent, + const char *compatible); extern struct device_node *of_get_child_by_name(const struct device_node *node, const char *name); @@ -412,6 +414,12 @@ static inline bool of_have_populated_dt(void) return false; } +static inline struct device_node *of_get_compatible_child(const struct device_node *parent, + const char *compatible) +{ + return NULL; +} + static inline struct device_node *of_get_child_by_name( const struct device_node *node, const char *name) |