diff options
| author |   Johan Hovold <johan@kernel.org> | 2018-08-27 10:21:45 +0200 |
|---|---|---|
| committer |   Rob Herring <robh@kernel.org> | 2018-08-29 08:06:46 -0500 |
| commit | 36156f9241cb0f9e37d998052873ca7501ad4b36 (patch) | |
| tree | 203d1e52a9e5a942a2b99ae0ecb984fa87453df8 /include | |
| parent | Linux 4.19-rc1 (diff) | |
| download | linux-dev-36156f9241cb0f9e37d998052873ca7501ad4b36.tar.xz linux-dev-36156f9241cb0f9e37d998052873ca7501ad4b36.zip | |
of: add helper to lookup compatible child node
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>
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 4d25e4f952d9..b99a1a8c2952 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -290,6 +290,8 @@ 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); @@ -632,6 +634,12 @@ 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) |