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-rw-r--r--drivers/gpio/gpio-pca953x.c16
-rw-r--r--drivers/i2c/i2c-core.c10
2 files changed, 24 insertions, 2 deletions
diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c
index 45c8817d068c..e422568e14ad 100644
--- a/drivers/gpio/gpio-pca953x.c
+++ b/drivers/gpio/gpio-pca953x.c
@@ -794,6 +794,22 @@ static int pca953x_probe(struct i2c_client *client,
}
mutex_init(&chip->i2c_lock);
+ /*
+ * In case we have an i2c-mux controlled by a GPIO provided by an
+ * expander using the same driver higher on the device tree, read the
+ * i2c adapter nesting depth and use the retrieved value as lockdep
+ * subclass for chip->i2c_lock.
+ *
+ * REVISIT: This solution is not complete. It protects us from lockdep
+ * false positives when the expander controlling the i2c-mux is on
+ * a different level on the device tree, but not when it's on the same
+ * level on a different branch (in which case the subclass number
+ * would be the same).
+ *
+ * TODO: Once a correct solution is developed, a similar fix should be
+ * applied to all other i2c-controlled GPIO expanders (and potentially
+ * regmap-i2c).
+ */
lockdep_set_subclass(&chip->i2c_lock,
i2c_adapter_depth(client->adapter));
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 98fffa3a09f7..5ab67219f71e 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -1680,7 +1680,7 @@ static struct i2c_client *of_i2c_register_device(struct i2c_adapter *adap,
static void of_i2c_register_devices(struct i2c_adapter *adap)
{
- struct device_node *node;
+ struct device_node *bus, *node;
/* Only register child devices if the adapter has a node pointer set */
if (!adap->dev.of_node)
@@ -1688,11 +1688,17 @@ static void of_i2c_register_devices(struct i2c_adapter *adap)
dev_dbg(&adap->dev, "of_i2c: walking child nodes\n");
- for_each_available_child_of_node(adap->dev.of_node, node) {
+ bus = of_get_child_by_name(adap->dev.of_node, "i2c-bus");
+ if (!bus)
+ bus = of_node_get(adap->dev.of_node);
+
+ for_each_available_child_of_node(bus, node) {
if (of_node_test_and_set_flag(node, OF_POPULATED))
continue;
of_i2c_register_device(adap, node);
}
+
+ of_node_put(bus);
}
static int of_dev_node_match(struct device *dev, void *data)