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>

2 files changed, 23 insertions, 10 deletions

diff --git a/drivers/media/platform/exynos4-is/media-dev.c b/drivers/media/platform/exynos4-is/media-dev.c
index 18a393f51a26..fbad0635c6b5 100644
--- a/drivers/media/platform/exynos4-is/media-dev.c
+++ b/drivers/media/platform/exynos4-is/media-dev.c
@@ -457,11 +457,16 @@ static int fimc_md_parse_port_node(struct fimc_md *fmd,
 
 	fmd->sensor[index].asd.match_type = V4L2_ASYNC_MATCH_FWNODE;
 	fmd->sensor[index].asd.match.fwnode = of_fwnode_handle(rem);
-	fmd->async_subdevs[index] = &fmd->sensor[index].asd;
+
+	ret = v4l2_async_notifier_add_subdev(&fmd->subdev_notifier,
+					     &fmd->sensor[index].asd);
+	if (ret) {
+		of_node_put(rem);
+		return ret;
+	}
 
 	fmd->num_sensors++;
 
-	of_node_put(rem);
 	return 0;
 }
 
@@ -500,7 +505,7 @@ static int fimc_md_register_sensor_entities(struct fimc_md *fmd)
 		ret = fimc_md_parse_port_node(fmd, port, index);
 		if (ret < 0) {
 			of_node_put(node);
-			goto rpm_put;
+			goto cleanup;
 		}
 		index++;
 	}
@@ -514,12 +519,18 @@ static int fimc_md_register_sensor_entities(struct fimc_md *fmd)
 		ret = fimc_md_parse_port_node(fmd, node, index);
 		if (ret < 0) {
 			of_node_put(node);
-			break;
+			goto cleanup;
 		}
 		index++;
 	}
+
 rpm_put:
 	pm_runtime_put(fmd->pmf);
+	return 0;
+
+cleanup:
+	v4l2_async_notifier_cleanup(&fmd->subdev_notifier);
+	pm_runtime_put(fmd->pmf);
 	return ret;
 }
 
@@ -1460,6 +1471,8 @@ static int fimc_md_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, fmd);
 
+	v4l2_async_notifier_init(&fmd->subdev_notifier);
+
 	ret = fimc_md_register_platform_entities(fmd, dev->of_node);
 	if (ret)
 		goto err_clk;
@@ -1470,7 +1483,7 @@ static int fimc_md_probe(struct platform_device *pdev)
 
 	ret = device_create_file(&pdev->dev, &dev_attr_subdev_conf_mode);
 	if (ret)
-		goto err_m_ent;
+		goto err_cleanup;
 	/*
 	 * FIMC platform devices need to be registered before the sclk_cam
 	 * clocks provider, as one of these devices needs to be activated
@@ -1483,8 +1496,6 @@ static int fimc_md_probe(struct platform_device *pdev)
 	}
 
 	if (fmd->num_sensors > 0) {
-		fmd->subdev_notifier.subdevs = fmd->async_subdevs;
-		fmd->subdev_notifier.num_subdevs = fmd->num_sensors;
 		fmd->subdev_notifier.ops = &subdev_notifier_ops;
 		fmd->num_sensors = 0;
 
@@ -1500,10 +1511,12 @@ err_clk_p:
 	fimc_md_unregister_clk_provider(fmd);
 err_attr:
 	device_remove_file(&pdev->dev, &dev_attr_subdev_conf_mode);
-err_clk:
-	fimc_md_put_clocks(fmd);
+err_cleanup:
+	v4l2_async_notifier_cleanup(&fmd->subdev_notifier);
 err_m_ent:
 	fimc_md_unregister_entities(fmd);
+err_clk:
+	fimc_md_put_clocks(fmd);
 err_md:
 	media_device_cleanup(&fmd->media_dev);
 	v4l2_device_unregister(&fmd->v4l2_dev);
@@ -1519,6 +1532,7 @@ static int fimc_md_remove(struct platform_device *pdev)
 
 	fimc_md_unregister_clk_provider(fmd);
 	v4l2_async_notifier_unregister(&fmd->subdev_notifier);
+	v4l2_async_notifier_cleanup(&fmd->subdev_notifier);
 
 	v4l2_device_unregister(&fmd->v4l2_dev);
 	device_remove_file(&pdev->dev, &dev_attr_subdev_conf_mode);
diff --git a/drivers/media/platform/exynos4-is/media-dev.h b/drivers/media/platform/exynos4-is/media-dev.h
index 957787a2f480..9f527670395a 100644
--- a/drivers/media/platform/exynos4-is/media-dev.h
+++ b/drivers/media/platform/exynos4-is/media-dev.h
@@ -149,7 +149,6 @@ struct fimc_md {
 	} clk_provider;
 
 	struct v4l2_async_notifier subdev_notifier;
-	struct v4l2_async_subdev *async_subdevs[FIMC_MAX_SENSORS];
 
 	bool user_subdev_api;
 	spinlock_t slock;