[PATCH 3.16 216/254] i2c: core: decrease reference count of device node in i2c_unregister_device

[Ben Hutchings]

3.16.55-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Lixin Wang <alan.1.wang@xxxxxxxxxxxxxxx>

commit e0638fa400eaccf9fa8060f67140264c4e276552 upstream.

Reference count of device node was increased in of_i2c_register_device,
but without decreasing it in i2c_unregister_device. Then the added
device node will never be released. Fix this by adding the of_node_put.

Signed-off-by: Lixin Wang <alan.1.wang@xxxxxxxxxxxxxxx>
Tested-by: Wolfram Sang <wsa@xxxxxxxxxxxxx>
Signed-off-by: Wolfram Sang <wsa@xxxxxxxxxxxxx>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 drivers/i2c/i2c-core.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -740,6 +740,10 @@ EXPORT_SYMBOL_GPL(i2c_new_device);
  */
 void i2c_unregister_device(struct i2c_client *client)
 {
+	if (client->dev.of_node) {
+		of_node_put(client->dev.of_node);
+	}
+
 	device_unregister(&client->dev);
 }
 EXPORT_SYMBOL_GPL(i2c_unregister_device);