[PATCH] drm/kmb: Replace of_node_put() with automatic cleanup handler

From: Javier Carrasco
Date: Wed Apr 10 2024 - 16:46:03 EST


Make use of the __free() cleanup handler to automatically free nodes
when they get out of scope.

Suggested-by: Julia Lawall <julia.lawall@xxxxxxxx>
Signed-off-by: Javier Carrasco <javier.carrasco.cruz@xxxxxxxxx>
---
The patch is based on the latest linux-next tag (next-20240410).
---
drivers/gpu/drm/kmb/kmb_drv.c | 13 ++++---------
drivers/gpu/drm/kmb/kmb_dsi.c | 11 ++++-------
2 files changed, 8 insertions(+), 16 deletions(-)

diff --git a/drivers/gpu/drm/kmb/kmb_drv.c b/drivers/gpu/drm/kmb/kmb_drv.c
index 169b83987ce2..1a743840688a 100644
--- a/drivers/gpu/drm/kmb/kmb_drv.c
+++ b/drivers/gpu/drm/kmb/kmb_drv.c
@@ -480,8 +480,8 @@ static int kmb_probe(struct platform_device *pdev)
struct device *dev = get_device(&pdev->dev);
struct kmb_drm_private *kmb;
int ret = 0;
- struct device_node *dsi_in;
- struct device_node *dsi_node;
+ struct device_node *dsi_in __free(device_node) =
+ of_graph_get_endpoint_by_regs(dev->of_node, 0, 0);
struct platform_device *dsi_pdev;

/* The bridge (ADV 7535) will return -EPROBE_DEFER until it
@@ -491,28 +491,23 @@ static int kmb_probe(struct platform_device *pdev)
* and then the rest of the driver initialization can proceed
* afterwards and the bridge can be successfully attached.
*/
- dsi_in = of_graph_get_endpoint_by_regs(dev->of_node, 0, 0);
if (!dsi_in) {
DRM_ERROR("Failed to get dsi_in node info from DT");
return -EINVAL;
}
- dsi_node = of_graph_get_remote_port_parent(dsi_in);
+ struct device_node *dsi_node __free(device_node) =
+ of_graph_get_remote_port_parent(dsi_in);
if (!dsi_node) {
- of_node_put(dsi_in);
DRM_ERROR("Failed to get dsi node from DT\n");
return -EINVAL;
}

dsi_pdev = of_find_device_by_node(dsi_node);
if (!dsi_pdev) {
- of_node_put(dsi_in);
- of_node_put(dsi_node);
DRM_ERROR("Failed to get dsi platform device\n");
return -EINVAL;
}

- of_node_put(dsi_in);
- of_node_put(dsi_node);
ret = kmb_dsi_host_bridge_init(get_device(&dsi_pdev->dev));

if (ret == -EPROBE_DEFER) {
diff --git a/drivers/gpu/drm/kmb/kmb_dsi.c b/drivers/gpu/drm/kmb/kmb_dsi.c
index cf7cf0b07541..61f02462b778 100644
--- a/drivers/gpu/drm/kmb/kmb_dsi.c
+++ b/drivers/gpu/drm/kmb/kmb_dsi.c
@@ -216,8 +216,6 @@ static const struct mipi_dsi_host_ops kmb_dsi_host_ops = {

int kmb_dsi_host_bridge_init(struct device *dev)
{
- struct device_node *encoder_node, *dsi_out;
-
/* Create and register MIPI DSI host */
if (!dsi_host) {
dsi_host = kzalloc(sizeof(*dsi_host), GFP_KERNEL);
@@ -239,21 +237,20 @@ int kmb_dsi_host_bridge_init(struct device *dev)
}

/* Find ADV7535 node and initialize it */
- dsi_out = of_graph_get_endpoint_by_regs(dev->of_node, 0, 1);
+ struct device_node *dsi_out __free(device_node) =
+ of_graph_get_endpoint_by_regs(dev->of_node, 0, 1);
if (!dsi_out) {
DRM_ERROR("Failed to get dsi_out node info from DT\n");
return -EINVAL;
}
- encoder_node = of_graph_get_remote_port_parent(dsi_out);
+ struct device_node *encoder_node __free(device_node) =
+ of_graph_get_remote_port_parent(dsi_out);
if (!encoder_node) {
- of_node_put(dsi_out);
DRM_ERROR("Failed to get bridge info from DT\n");
return -EINVAL;
}
/* Locate drm bridge from the hdmi encoder DT node */
adv_bridge = of_drm_find_bridge(encoder_node);
- of_node_put(dsi_out);
- of_node_put(encoder_node);
if (!adv_bridge) {
DRM_DEBUG("Wait for external bridge driver DT\n");
return -EPROBE_DEFER;

---
base-commit: 6ebf211bb11dfc004a2ff73a9de5386fa309c430
change-id: 20240410-kmb_of_node_put-aaf1c77d9610

Best regards,
--
Javier Carrasco <javier.carrasco.cruz@xxxxxxxxx>