linux-kernel - [PATCH 25/26] drm/bridge: imx8qxp-pixel-link: simplify freeing of the remote device

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Message-Id: <20251119-drm-bridge-alloc-getput-drm_of_find_bridge-v1-25-0db98a7fe474@bootlin.com>
Date: Wed, 19 Nov 2025 14:05:56 +0100
From: Luca Ceresoli <luca.ceresoli@...tlin.com>
To: Andrzej Hajda <andrzej.hajda@...el.com>, 
 Neil Armstrong <neil.armstrong@...aro.org>, Robert Foss <rfoss@...nel.org>, 
 Laurent Pinchart <Laurent.pinchart@...asonboard.com>, 
 Jonas Karlman <jonas@...boo.se>, Jernej Skrabec <jernej.skrabec@...il.com>, 
 Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>, 
 Maxime Ripard <mripard@...nel.org>, Thomas Zimmermann <tzimmermann@...e.de>, 
 David Airlie <airlied@...il.com>, Simona Vetter <simona@...ll.ch>, 
 Jonathan Corbet <corbet@....net>, Alexey Brodkin <abrodkin@...opsys.com>, 
 Phong LE <ple@...libre.com>, Liu Ying <victor.liu@....com>, 
 Shawn Guo <shawnguo@...nel.org>, Sascha Hauer <s.hauer@...gutronix.de>, 
 Pengutronix Kernel Team <kernel@...gutronix.de>, 
 Fabio Estevam <festevam@...il.com>, 
 Adrien Grassein <adrien.grassein@...il.com>, 
 Laurent Pinchart <laurent.pinchart+renesas@...asonboard.com>, 
 Tomi Valkeinen <tomi.valkeinen+renesas@...asonboard.com>, 
 Kieran Bingham <kieran.bingham+renesas@...asonboard.com>, 
 Geert Uytterhoeven <geert+renesas@...der.be>, 
 Magnus Damm <magnus.damm@...il.com>, Kevin Hilman <khilman@...libre.com>, 
 Jerome Brunet <jbrunet@...libre.com>, 
 Martin Blumenstingl <martin.blumenstingl@...glemail.com>, 
 Chun-Kuang Hu <chunkuang.hu@...nel.org>, 
 Philipp Zabel <p.zabel@...gutronix.de>, 
 Matthias Brugger <matthias.bgg@...il.com>, 
 AngeloGioacchino Del Regno <angelogioacchino.delregno@...labora.com>, 
 Anitha Chrisanthus <anitha.chrisanthus@...el.com>, 
 Edmund Dea <edmund.j.dea@...el.com>, Inki Dae <inki.dae@...sung.com>, 
 Seung-Woo Kim <sw0312.kim@...sung.com>, 
 Kyungmin Park <kyungmin.park@...sung.com>, 
 Krzysztof Kozlowski <krzk@...nel.org>, 
 Alim Akhtar <alim.akhtar@...sung.com>
Cc: Hui Pu <Hui.Pu@...ealthcare.com>, 
 Thomas Petazzoni <thomas.petazzoni@...tlin.com>, 
 dri-devel@...ts.freedesktop.org, linux-kernel@...r.kernel.org, 
 linux-doc@...r.kernel.org, imx@...ts.linux.dev, 
 linux-arm-kernel@...ts.infradead.org, linux-renesas-soc@...r.kernel.org, 
 linux-amlogic@...ts.infradead.org, linux-mediatek@...ts.infradead.org, 
 linux-samsung-soc@...r.kernel.org, 
 Luca Ceresoli <luca.ceresoli@...tlin.com>
Subject: [PATCH 25/26] drm/bridge: imx8qxp-pixel-link: simplify freeing of
 the remote device_node

The main loop in imx8qxp_pixel_link_find_next_bridge() requires calling
of_node_put() in multiple places, complicating code flow. Simplify it by
using a cleanup action and making the 'remote' variable scope local to the
loop.

Signed-off-by: Luca Ceresoli <luca.ceresoli@...tlin.com>

---

Cc: Liu Ying <victor.liu@....com>
---
 drivers/gpu/drm/bridge/imx/imx8qxp-pixel-link.c | 12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-link.c b/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-link.c
index 53016f0d53a0..2ecc3c1051e5 100644
--- a/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-link.c
+++ b/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-link.c
@@ -260,7 +260,7 @@ static struct drm_bridge *
 imx8qxp_pixel_link_find_next_bridge(struct imx8qxp_pixel_link *pl)
 {
 	struct device_node *np = pl->dev->of_node;
-	struct device_node *port, *remote;
+	struct device_node *port;
 	struct drm_bridge *selected_bridge = NULL;
 	u32 port_id;
 	bool found_port = false;
@@ -286,7 +286,8 @@ imx8qxp_pixel_link_find_next_bridge(struct imx8qxp_pixel_link *pl)
 	}
 
 	for (reg = 0; reg < PL_MAX_NEXT_BRIDGES; reg++) {
-		remote = of_graph_get_remote_node(np, port_id, reg);
+		struct device_node *remote __free(device_node) =
+			of_graph_get_remote_node(np, port_id, reg);
 		if (!remote)
 			continue;
 
@@ -294,15 +295,12 @@ imx8qxp_pixel_link_find_next_bridge(struct imx8qxp_pixel_link *pl)
 			DRM_DEV_DEBUG(pl->dev,
 				      "port%u endpoint%u remote parent is not available\n",
 				      port_id, reg);
-			of_node_put(remote);
 			continue;
 		}
 
 		struct drm_bridge *next_bridge = of_drm_find_bridge(remote);
-		if (!next_bridge) {
-			of_node_put(remote);
+		if (!next_bridge)
 			return ERR_PTR(-EPROBE_DEFER);
-		}
 
 		/*
 		 * Select the next bridge with companion PXL2DPI if
@@ -310,8 +308,6 @@ imx8qxp_pixel_link_find_next_bridge(struct imx8qxp_pixel_link *pl)
 		 */
 		if (!selected_bridge || of_property_present(remote, "fsl,companion-pxl2dpi"))
 			selected_bridge = next_bridge;
-
-		of_node_put(remote);
 	}
 
 	pl->mst_addr = port_id - 1;

-- 
2.51.1