---

yaml --- r: 308470 b: refs/heads/master c: 643dd09 h: refs/heads/master v: v3
git-mirror · May 12, 2012 · ea2a5a8 · ea2a5a8
1 parent 7c4fd76
commit ea2a5a8
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Showing 3 changed files with 19 additions and 1 deletion.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: ec39ef83eb9b22cc732329e85fc4ec03e76d9dda
+refs/heads/master: 643dd09eb27b40ced671564edbe2640935fe37c2
diff --git a/trunk/drivers/i2c/i2c-core.c b/trunk/drivers/i2c/i2c-core.c
@@ -772,6 +772,23 @@ struct device_type i2c_adapter_type = {
 };
 EXPORT_SYMBOL_GPL(i2c_adapter_type);
 
+/**
+ * i2c_verify_adapter - return parameter as i2c_adapter or NULL
+ * @dev: device, probably from some driver model iterator
+ *
+ * When traversing the driver model tree, perhaps using driver model
+ * iterators like @device_for_each_child(), you can't assume very much
+ * about the nodes you find.  Use this function to avoid oopses caused
+ * by wrongly treating some non-I2C device as an i2c_adapter.
+ */
+struct i2c_adapter *i2c_verify_adapter(struct device *dev)
+{
+	return (dev->type == &i2c_adapter_type)
+			? to_i2c_adapter(dev)
+			: NULL;
+}
+EXPORT_SYMBOL(i2c_verify_adapter);
+
 #ifdef CONFIG_I2C_COMPAT
 static struct class_compat *i2c_adapter_compat_class;
 #endif

diff --git a/trunk/include/linux/i2c.h b/trunk/include/linux/i2c.h
@@ -232,6 +232,7 @@ struct i2c_client {
 #define to_i2c_client(d) container_of(d, struct i2c_client, dev)
 
 extern struct i2c_client *i2c_verify_client(struct device *dev);
+extern struct i2c_adapter *i2c_verify_adapter(struct device *dev);
 
 static inline struct i2c_client *kobj_to_i2c_client(struct kobject *kobj)
 {