i2c: core: add managed function for adding i2c adapters

Some I2C controller drivers will only unregister the I2C
adapter in their .remove() callback, which can be done
by simply using a managed variant to add the I2C adapter.

So add the managed functions for adding the I2C adapter.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

drivers/i2c/i2c-core-base.c

@@ -1693,6 +1693,32 @@ void i2c_del_adapter(struct i2c_adapter *adap)
 }
 EXPORT_SYMBOL(i2c_del_adapter);
 
+static void devm_i2c_del_adapter(void *adapter)
+{
+	i2c_del_adapter(adapter);
+}
+
+/**
+ * devm_i2c_add_adapter - device-managed variant of i2c_add_adapter()
+ * @dev: managing device for adding this I2C adapter
+ * @adapter: the adapter to add
+ * Context: can sleep
+ *
+ * Add adapter with dynamic bus number, same with i2c_add_adapter()
+ * but the adapter will be auto deleted on driver detach.
+ */
+int devm_i2c_add_adapter(struct device *dev, struct i2c_adapter *adapter)
+{
+	int ret;
+
+	ret = i2c_add_adapter(adapter);
+	if (ret)
+		return ret;
+
+	return devm_add_action_or_reset(dev, devm_i2c_del_adapter, adapter);
+}
+EXPORT_SYMBOL_GPL(devm_i2c_add_adapter);
+
 static void i2c_parse_timing(struct device *dev, char *prop_name, u32 *cur_val_p,
 			    u32 def_val, bool use_def)
 {

include/linux/i2c.h

@@ -846,6 +846,7 @@ static inline void i2c_mark_adapter_resumed(struct i2c_adapter *adap)
  */
 #if IS_ENABLED(CONFIG_I2C)
 int i2c_add_adapter(struct i2c_adapter *adap);
+int devm_i2c_add_adapter(struct device *dev, struct i2c_adapter *adapter);
 void i2c_del_adapter(struct i2c_adapter *adap);
 int i2c_add_numbered_adapter(struct i2c_adapter *adap);