media: v4l2-async: Clean v4l2_async_notifier_add_fwnode_remote_subdev

Change v4l2_async_notifier_add_fwnode_remote_subdev semantics
so it allocates the struct v4l2_async_subdev pointer.

This makes the API consistent: the v4l2-async subdevice addition
functions have now a unified usage model. This model is simpler,
as it makes v4l2-async responsible for the allocation and release
of the subdevice descriptor, and no longer something the driver
has to worry about.

On the user side, the change makes the API simpler for the drivers
to use and less error-prone.

Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Helen Koike <helen.koike@collabora.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

4 files changed, 20 insertions, 44 deletions

diff --git a/drivers/staging/media/imx/imx-media-csi.c b/drivers/staging/media/imx/imx-media-csi.c
index db77fef07654..6344389e6afa 100644
--- a/drivers/staging/media/imx/imx-media-csi.c
+++ b/drivers/staging/media/imx/imx-media-csi.c
@@ -1922,19 +1922,13 @@ static int imx_csi_async_register(struct csi_priv *priv)
 					     port, 0,
 					     FWNODE_GRAPH_ENDPOINT_NEXT);
 	if (ep) {
-		asd = kzalloc(sizeof(*asd), GFP_KERNEL);
-		if (!asd) {
-			fwnode_handle_put(ep);
-			return -ENOMEM;
-		}
-
-		ret = v4l2_async_notifier_add_fwnode_remote_subdev(
-			&priv->notifier, ep, asd);
+		asd = v4l2_async_notifier_add_fwnode_remote_subdev(
+			&priv->notifier, ep, sizeof(*asd));
 
 		fwnode_handle_put(ep);
 
-		if (ret) {
-			kfree(asd);
+		if (IS_ERR(asd)) {
+			ret = PTR_ERR(asd);
 			/* OK if asd already exists */
 			if (ret != -EEXIST)
 				return ret;
diff --git a/drivers/staging/media/imx/imx6-mipi-csi2.c b/drivers/staging/media/imx/imx6-mipi-csi2.c
index 6b58899dcefe..a79ab38158e2 100644
--- a/drivers/staging/media/imx/imx6-mipi-csi2.c
+++ b/drivers/staging/media/imx/imx6-mipi-csi2.c
@@ -641,7 +641,7 @@ static int csi2_async_register(struct csi2_dev *csi2)
 	struct v4l2_fwnode_endpoint vep = {
 		.bus_type = V4L2_MBUS_CSI2_DPHY,
 	};
-	struct v4l2_async_subdev *asd = NULL;
+	struct v4l2_async_subdev *asd;
 	struct fwnode_handle *ep;
 	int ret;
 
@@ -661,19 +661,13 @@ static int csi2_async_register(struct csi2_dev *csi2)
 	dev_dbg(csi2->dev, "data lanes: %d\n", vep.bus.mipi_csi2.num_data_lanes);
 	dev_dbg(csi2->dev, "flags: 0x%08x\n", vep.bus.mipi_csi2.flags);
 
-	asd = kzalloc(sizeof(*asd), GFP_KERNEL);
-	if (!asd) {
-		ret = -ENOMEM;
-		goto err_parse;
-	}
-
-	ret = v4l2_async_notifier_add_fwnode_remote_subdev(
-		&csi2->notifier, ep, asd);
-	if (ret)
-		goto err_parse;
-
+	asd = v4l2_async_notifier_add_fwnode_remote_subdev(
+		&csi2->notifier, ep, sizeof(*asd));
 	fwnode_handle_put(ep);
 
+	if (IS_ERR(asd))
+		return PTR_ERR(asd);
+
 	csi2->notifier.ops = &csi2_notify_ops;
 
 	ret = v4l2_async_subdev_notifier_register(&csi2->sd,
@@ -685,7 +679,6 @@ static int csi2_async_register(struct csi2_dev *csi2)
 
 err_parse:
 	fwnode_handle_put(ep);
-	kfree(asd);
 	return ret;
 }
 
diff --git a/drivers/staging/media/imx/imx7-media-csi.c b/drivers/staging/media/imx/imx7-media-csi.c
index ac52b1daf991..6c59485291ca 100644
--- a/drivers/staging/media/imx/imx7-media-csi.c
+++ b/drivers/staging/media/imx/imx7-media-csi.c
@@ -1191,7 +1191,7 @@ static const struct v4l2_async_notifier_operations imx7_csi_notify_ops = {
 
 static int imx7_csi_async_register(struct imx7_csi *csi)
 {
-	struct v4l2_async_subdev *asd = NULL;
+	struct v4l2_async_subdev *asd;
 	struct fwnode_handle *ep;
 	int ret;
 
@@ -1200,19 +1200,13 @@ static int imx7_csi_async_register(struct imx7_csi *csi)
 	ep = fwnode_graph_get_endpoint_by_id(dev_fwnode(csi->dev), 0, 0,
 					     FWNODE_GRAPH_ENDPOINT_NEXT);
 	if (ep) {
-		asd = kzalloc(sizeof(*asd), GFP_KERNEL);
-		if (!asd) {
-			fwnode_handle_put(ep);
-			return -ENOMEM;
-		}
-
-		ret = v4l2_async_notifier_add_fwnode_remote_subdev(
-			&csi->notifier, ep, asd);
+		asd = v4l2_async_notifier_add_fwnode_remote_subdev(
+			&csi->notifier, ep, sizeof(*asd));
 
 		fwnode_handle_put(ep);
 
-		if (ret) {
-			kfree(asd);
+		if (IS_ERR(asd)) {
+			ret = PTR_ERR(asd);
 			/* OK if asd already exists */
 			if (ret != -EEXIST)
 				return ret;
diff --git a/drivers/staging/media/imx/imx7-mipi-csis.c b/drivers/staging/media/imx/imx7-mipi-csis.c
index 7612993cc1d6..1ba77e629e5b 100644
--- a/drivers/staging/media/imx/imx7-mipi-csis.c
+++ b/drivers/staging/media/imx/imx7-mipi-csis.c
@@ -1004,7 +1004,7 @@ static int mipi_csis_async_register(struct csi_state *state)
 	struct v4l2_fwnode_endpoint vep = {
 		.bus_type = V4L2_MBUS_CSI2_DPHY,
 	};
-	struct v4l2_async_subdev *asd = NULL;
+	struct v4l2_async_subdev *asd;
 	struct fwnode_handle *ep;
 	int ret;
 
@@ -1024,17 +1024,13 @@ static int mipi_csis_async_register(struct csi_state *state)
 	dev_dbg(state->dev, "data lanes: %d\n", state->bus.num_data_lanes);
 	dev_dbg(state->dev, "flags: 0x%08x\n", state->bus.flags);
 
-	asd = kzalloc(sizeof(*asd), GFP_KERNEL);
-	if (!asd) {
-		ret = -ENOMEM;
+	asd = v4l2_async_notifier_add_fwnode_remote_subdev(
+		&state->notifier, ep, sizeof(*asd));
+	if (IS_ERR(asd)) {
+		ret = PTR_ERR(asd);
 		goto err_parse;
 	}
 
-	ret = v4l2_async_notifier_add_fwnode_remote_subdev(
-		&state->notifier, ep, asd);
-	if (ret)
-		goto err_parse;
-
 	fwnode_handle_put(ep);
 
 	state->notifier.ops = &mipi_csis_notify_ops;
@@ -1048,7 +1044,6 @@ static int mipi_csis_async_register(struct csi_state *state)
 
 err_parse:
 	fwnode_handle_put(ep);
-	kfree(asd);
 
 	return ret;
 }