i2c: core: Add support for 'i2c-bus' subnode

If the 'i2c-bus' device-tree node is present for an I2C adapter then
parse this subnode for I2C slaves.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Thierry Reding <treding@nvidia.com>

1 files changed, 8 insertions, 2 deletions

diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index af11b658984d..ed7002dd9401 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -1411,7 +1411,7 @@ 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)
@@ -1419,11 +1419,17 @@ 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)