drm/bridge: imx: Use of_node_put(remote) call only once in imx8qxp_pc_bridge_probe()

[PATCH] drm/bridge: imx: Use of_node_put(remote) call only once in imx8qxp_pc_bridge_probe()

Posted by Markus Elfring 2 months, 1 week ago

From: Markus Elfring <elfring@users.sourceforge.net>
Date: Tue, 17 Sep 2024 16:40:18 +0200

A of_node_put(remote) call was immediately used after a null pointer check
for the data structure member “next_bridge” in this
function implementation.
Thus use such a function call only once instead directly before the check.

This issue was transformed by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
---
 drivers/gpu/drm/bridge/imx/imx8qxp-pixel-combiner.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-combiner.c b/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-combiner.c
index e6dbbdc87ce2..0064d37ad8f6 100644
--- a/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-combiner.c
+++ b/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-combiner.c
@@ -321,8 +321,8 @@ static int imx8qxp_pc_bridge_probe(struct platform_device *pdev)
 		}

 		ch->next_bridge = of_drm_find_bridge(remote);
+		of_node_put(remote);
 		if (!ch->next_bridge) {
-			of_node_put(remote);
 			ret = -EPROBE_DEFER;
 			DRM_DEV_DEBUG_DRIVER(dev,
 					     "channel%u failed to find next bridge: %d\n",
@@ -330,8 +330,6 @@ static int imx8qxp_pc_bridge_probe(struct platform_device *pdev)
 			goto free_child;
 		}

-		of_node_put(remote);
-
 		ch->bridge.driver_private = ch;
 		ch->bridge.funcs = &imx8qxp_pc_bridge_funcs;
 		ch->bridge.of_node = child;
--
2.46.0

Re: [PATCH] drm/bridge: imx: Use of_node_put(remote) call only once in imx8qxp_pc_bridge_probe()

Posted by Liu Ying 2 months, 1 week ago

On 09/17/2024, Markus Elfring wrote:
> From: Markus Elfring <elfring@users.sourceforge.net>
> Date: Tue, 17 Sep 2024 16:40:18 +0200
> 
> A of_node_put(remote) call was immediately used after a null pointer check
> for the data structure member “next_bridge” in this
> function implementation.
> Thus use such a function call only once instead directly before the check.
> 
> This issue was transformed by using the Coccinelle software.
> 
> Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
> ---
>  drivers/gpu/drm/bridge/imx/imx8qxp-pixel-combiner.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)

The patch subject should be something like

drm/bridge: imx8qxp-pixel-combiner: Call of_node_put(remote) only once in probe function

so that the prefixes may tell the driver the patch touches,
just like some other previous patches did for this driver
shown by 'git log'.

Not sure if it is worth a v2 just for that.
Maybe, a patch committer can fix it before pushing.

With the patch subject fixed:
Reviewed-by: Liu Ying <victor.liu@nxp.com>

> 
> diff --git a/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-combiner.c b/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-combiner.c
> index e6dbbdc87ce2..0064d37ad8f6 100644
> --- a/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-combiner.c
> +++ b/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-combiner.c
> @@ -321,8 +321,8 @@ static int imx8qxp_pc_bridge_probe(struct platform_device *pdev)
>  		}
> 
>  		ch->next_bridge = of_drm_find_bridge(remote);
> +		of_node_put(remote);
>  		if (!ch->next_bridge) {
> -			of_node_put(remote);
>  			ret = -EPROBE_DEFER;
>  			DRM_DEV_DEBUG_DRIVER(dev,
>  					     "channel%u failed to find next bridge: %d\n",
> @@ -330,8 +330,6 @@ static int imx8qxp_pc_bridge_probe(struct platform_device *pdev)
>  			goto free_child;
>  		}
> 
> -		of_node_put(remote);
> -
>  		ch->bridge.driver_private = ch;
>  		ch->bridge.funcs = &imx8qxp_pc_bridge_funcs;
>  		ch->bridge.of_node = child;
> --
> 2.46.0
> 

-- 
Regards,
Liu Ying