media: platform: Switch to v4l2_async_notifier_add_subdev

Switch all media platform drivers to call v4l2_async_notifier_add_subdev()
to add asd's to a notifier, in place of referencing the notifier->subdevs[]
array. These drivers also must now call v4l2_async_notifier_init() before
adding asd's to their notifiers.

There may still be cases where a platform driver maintains a list of
asd's that is a duplicate of the notifier asd_list, in which case its
possible the platform driver list can be removed, and can reference the
notifier asd_list instead. One example of where a duplicate list has
been removed in this patch is xilinx-vipp.c. If there are such cases
remaining, those drivers should be optimized to remove the duplicate
platform driver asd lists.

None of the changes to the platform drivers in this patch have been
tested. Verify that the async subdevices needed by the platform are
bound at load time, and that the driver unloads and reloads correctly
with no memory leaking of asd objects.

Suggested-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

1 files changed, 25 insertions, 10 deletions

diff --git a/drivers/media/platform/soc_camera/soc_camera.c b/drivers/media/platform/soc_camera/soc_camera.c
index 44b6859d7238..0a70fb67c401 100644
--- a/drivers/media/platform/soc_camera/soc_camera.c
+++ b/drivers/media/platform/soc_camera/soc_camera.c
@@ -1442,8 +1442,14 @@ static int scan_async_group(struct soc_camera_host *ici,
 		goto eaddpdev;
 	}
 
-	sasc->notifier.subdevs = asd;
-	sasc->notifier.num_subdevs = size;
+	v4l2_async_notifier_init(&sasc->notifier);
+
+	for (i = 0; i < size; i++) {
+		ret = v4l2_async_notifier_add_subdev(&sasc->notifier, asd[i]);
+		if (ret)
+			goto eaddasd;
+	}
+
 	sasc->notifier.ops = &soc_camera_async_ops;
 
 	icd->sasc = sasc;
@@ -1466,6 +1472,8 @@ static int scan_async_group(struct soc_camera_host *ici,
 	v4l2_clk_unregister(icd->clk);
 eclkreg:
 	icd->clk = NULL;
+eaddasd:
+	v4l2_async_notifier_cleanup(&sasc->notifier);
 	platform_device_del(sasc->pdev);
 eaddpdev:
 	platform_device_put(sasc->pdev);
@@ -1540,8 +1548,14 @@ static int soc_of_bind(struct soc_camera_host *ici,
 		goto eaddpdev;
 	}
 
-	sasc->notifier.subdevs = &info->subdev;
-	sasc->notifier.num_subdevs = 1;
+	v4l2_async_notifier_init(&sasc->notifier);
+
+	ret = v4l2_async_notifier_add_subdev(&sasc->notifier, info->subdev);
+	if (ret) {
+		of_node_put(remote);
+		goto eaddasd;
+	}
+
 	sasc->notifier.ops = &soc_camera_async_ops;
 
 	icd->sasc = sasc;
@@ -1568,6 +1582,8 @@ static int soc_of_bind(struct soc_camera_host *ici,
 	v4l2_clk_unregister(icd->clk);
 eclkreg:
 	icd->clk = NULL;
+eaddasd:
+	v4l2_async_notifier_cleanup(&sasc->notifier);
 	platform_device_del(sasc->pdev);
 eaddpdev:
 	platform_device_put(sasc->pdev);
@@ -1582,7 +1598,7 @@ static void scan_of_host(struct soc_camera_host *ici)
 {
 	struct device *dev = ici->v4l2_dev.dev;
 	struct device_node *np = dev->of_node;
-	struct device_node *epn = NULL, *ren;
+	struct device_node *epn = NULL, *rem;
 	unsigned int i;
 
 	for (i = 0; ; i++) {
@@ -1590,17 +1606,15 @@ static void scan_of_host(struct soc_camera_host *ici)
 		if (!epn)
 			break;
 
-		ren = of_graph_get_remote_port(epn);
-		if (!ren) {
+		rem = of_graph_get_remote_port_parent(epn);
+		if (!rem) {
 			dev_notice(dev, "no remote for %pOF\n", epn);
 			continue;
 		}
 
 		/* so we now have a remote node to connect */
 		if (!i)
-			soc_of_bind(ici, epn, ren->parent);
-
-		of_node_put(ren);
+			soc_of_bind(ici, epn, rem);
 
 		if (i) {
 			dev_err(dev, "multiple subdevices aren't supported yet!\n");
@@ -1926,6 +1940,7 @@ void soc_camera_host_unregister(struct soc_camera_host *ici)
 	list_for_each_entry(sasc, &notifiers, list) {
 		/* Must call unlocked to avoid AB-BA dead-lock */
 		v4l2_async_notifier_unregister(&sasc->notifier);
+		v4l2_async_notifier_cleanup(&sasc->notifier);
 		put_device(&sasc->pdev->dev);
 	}