media: davinci: vpif_display: Mix memory leak on probe error path

If vpif_probe() fails on v4l2_device_register() then memory allocated
at initialize_vpif() for global vpif_obj.dev[i] become unreleased.

The patch adds deallocation of vpif_obj.dev[i] on the error path and
removes duplicated check on platform_data presence.

Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: Anton Vasilyev <vasilyev@ispras.ru>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

drivers/media/platform/davinci/vpif_display.c

@@ -1114,6 +1114,14 @@ static int initialize_vpif(void)
 	return err;
 }
 
+static void free_vpif_objs(void)
+{
+	int i;
+
+	for (i = 0; i < VPIF_DISPLAY_MAX_DEVICES; i++)
+		kfree(vpif_obj.dev[i]);
+}
+
 static int vpif_async_bound(struct v4l2_async_notifier *notifier,
 			    struct v4l2_subdev *subdev,
 			    struct v4l2_async_subdev *asd)
@@ -1255,11 +1263,6 @@ static __init int vpif_probe(struct platform_device *pdev)
 		return -EINVAL;
 	}
 
-	if (!pdev->dev.platform_data) {
-		dev_warn(&pdev->dev, "Missing platform data.  Giving up.\n");
-		return -EINVAL;
-	}
-
 	vpif_dev = &pdev->dev;
 	err = initialize_vpif();
 
@@ -1271,7 +1274,7 @@ static __init int vpif_probe(struct platform_device *pdev)
 	err = v4l2_device_register(vpif_dev, &vpif_obj.v4l2_dev);
 	if (err) {
 		v4l2_err(vpif_dev->driver, "Error registering v4l2 device\n");
-		return err;
+		goto vpif_free;
 	}
 
 	while ((res = platform_get_resource(pdev, IORESOURCE_IRQ, res_idx))) {
@@ -1314,7 +1317,10 @@ static __init int vpif_probe(struct platform_device *pdev)
 			if (vpif_obj.sd[i])
 				vpif_obj.sd[i]->grp_id = 1 << i;
 		}
-		vpif_probe_complete();
+		err = vpif_probe_complete();
+		if (err) {
+			goto probe_subdev_out;
+		}
 	} else {
 		vpif_obj.notifier.subdevs = vpif_obj.config->asd;
 		vpif_obj.notifier.num_subdevs = vpif_obj.config->asd_sizes[0];
@@ -1334,6 +1340,8 @@ static __init int vpif_probe(struct platform_device *pdev)
 	kfree(vpif_obj.sd);
 vpif_unregister:
 	v4l2_device_unregister(&vpif_obj.v4l2_dev);
+vpif_free:
+	free_vpif_objs();
 
 	return err;
 }
@@ -1355,8 +1363,8 @@ static int vpif_remove(struct platform_device *device)
 		ch = vpif_obj.dev[i];
 		/* Unregister video device */
 		video_unregister_device(&ch->video_dev);
-		kfree(vpif_obj.dev[i]);
 	}
+	free_vpif_objs();
 
 	return 0;
 }