i2c: add a warning to i2c_adapter_depth()

[cascardo/linux.git] / drivers / i2c / i2c-core.c

diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 981de21..98fffa3 100644 (file)
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -1433,6 +1433,9 @@ unsigned int i2c_adapter_depth(struct i2c_adapter *adapter)
        while ((adapter = i2c_parent_is_i2c_adapter(adapter)))
                depth++;
 
+       WARN_ONCE(depth >= MAX_LOCKDEP_SUBCLASSES,
+                 "adapter depth exceeds lockdep subclass limit\n");
+
        return depth;
 }
 EXPORT_SYMBOL_GPL(i2c_adapter_depth);