[media] V4L2: mt9m111: switch to asynchronous subdevice probing

Convert the mt9m111 driver to asynchronous subdevice probing. Synchronous
probing is also still possible.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

drivers/media/i2c/soc_camera/mt9m111.c

@@ -946,6 +946,10 @@ static int mt9m111_probe(struct i2c_client *client,
 	if (!mt9m111)
 		return -ENOMEM;
 
+	mt9m111->clk = v4l2_clk_get(&client->dev, "mclk");
+	if (IS_ERR(mt9m111->clk))
+		return -EPROBE_DEFER;
+
 	/* Default HIGHPOWER context */
 	mt9m111->ctx = &context_b;
 
@@ -963,8 +967,10 @@ static int mt9m111_probe(struct i2c_client *client,
 			&mt9m111_ctrl_ops, V4L2_CID_EXPOSURE_AUTO, 1, 0,
 			V4L2_EXPOSURE_AUTO);
 	mt9m111->subdev.ctrl_handler = &mt9m111->hdl;
-	if (mt9m111->hdl.error)
-		return mt9m111->hdl.error;
+	if (mt9m111->hdl.error) {
+		ret = mt9m111->hdl.error;
+		goto out_clkput;
+	}
 
 	/* Second stage probe - when a capture adapter is there */
 	mt9m111->rect.left	= MT9M111_MIN_DARK_COLS;
@@ -975,18 +981,25 @@ static int mt9m111_probe(struct i2c_client *client,
 	mt9m111->lastpage	= -1;
 	mutex_init(&mt9m111->power_lock);
 
-	mt9m111->clk = v4l2_clk_get(&client->dev, "mclk");
-	if (IS_ERR(mt9m111->clk)) {
-		ret = PTR_ERR(mt9m111->clk);
-		goto eclkget;
-	}
+	ret = soc_camera_power_init(&client->dev, ssdd);
+	if (ret < 0)
+		goto out_hdlfree;
 
 	ret = mt9m111_video_probe(client);
-	if (ret) {
-		v4l2_clk_put(mt9m111->clk);
-eclkget:
+	if (ret < 0)
+		goto out_hdlfree;
+
+	mt9m111->subdev.dev = &client->dev;
+	ret = v4l2_async_register_subdev(&mt9m111->subdev);
+	if (ret < 0)
+		goto out_hdlfree;
+
+	return 0;
+
+out_hdlfree:
 	v4l2_ctrl_handler_free(&mt9m111->hdl);
-	}
+out_clkput:
+	v4l2_clk_put(mt9m111->clk);
 
 	return ret;
 }
@@ -995,6 +1008,7 @@ static int mt9m111_remove(struct i2c_client *client)
 {
 	struct mt9m111 *mt9m111 = to_mt9m111(client);
 
+	v4l2_async_unregister_subdev(&mt9m111->subdev);
 	v4l2_clk_put(mt9m111->clk);
 	v4l2_device_unregister_subdev(&mt9m111->subdev);
 	v4l2_ctrl_handler_free(&mt9m111->hdl);