[PATCH v4 7/8] of/platform: Sanity check DT bindings before creating device links
From: Saravana Kannan <hidden>
Date: 2019-07-08 22:56:55
Also in:
lkml
Subsystem:
open firmware and flattened device tree, the rest · Maintainers:
Rob Herring, Saravana Kannan, Linus Torvalds
If a common DT binding is pointing to a child DT node of a particular parent DT node, don't add device links for such DT references. This is because, by definition, a child node can't be a functional dependency for the parent node. Signed-off-by: Saravana Kannan <redacted> --- drivers/of/platform.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+)
diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index dba962a0ee50..98414ba53b1f 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c@@ -512,6 +512,19 @@ int of_platform_default_populate(struct device_node *root, } EXPORT_SYMBOL_GPL(of_platform_default_populate); +bool of_link_is_valid(struct device_node *con, struct device_node *sup) +{ + of_node_get(sup); + while (sup) { + if (sup == con) { + of_node_put(sup); + return false; + } + sup = of_get_next_parent(sup); + } + return true; +} + static int of_link_binding(struct device *dev, const char *binding, const char *cell) {
@@ -522,6 +535,10 @@ static int of_link_binding(struct device *dev, while (!of_parse_phandle_with_args(dev->of_node, binding, cell, i, &sup_args)) { + if (!of_link_is_valid(dev->of_node, sup_args.np)) { + of_node_put(sup_args.np); + continue; + } i++; sup_dev = of_find_device_by_node(sup_args.np); of_node_put(sup_args.np);
--
2.22.0.410.gd8fdbe21b5-goog