linux-kernel - [PATCH v3 08/22] drm/bridge: imx8qxp-pixel-combiner: get/put the next bridge

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20251216-drm-bridge-alloc-getput-drm_of_find_bridge-v3-8-b5165fab8058@bootlin.com>
Date: Tue, 16 Dec 2025 18:58:41 +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>, Kevin Hilman <khilman@...libre.com>, 
 Jerome Brunet <jbrunet@...libre.com>, 
 Martin Blumenstingl <martin.blumenstingl@...glemail.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-amlogic@...ts.infradead.org, 
 Luca Ceresoli <luca.ceresoli@...tlin.com>
Subject: [PATCH v3 08/22] drm/bridge: imx8qxp-pixel-combiner: get/put the
 next bridge

This driver obtains a bridge pointer from of_drm_find_bridge() in the probe
function and stores it until driver removal. of_drm_find_bridge() is
deprecated. Move to of_drm_find_and_get_bridge() for the bridge to be
refcounted and use bridge->next_bridge to put the reference on
deallocation.

Signed-off-by: Luca Ceresoli <luca.ceresoli@...tlin.com>
---
 drivers/gpu/drm/bridge/imx/imx8qxp-pixel-combiner.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-combiner.c b/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-combiner.c
index 8517b1c953d4..74eda8b54023 100644
--- a/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-combiner.c
+++ b/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-combiner.c
@@ -60,7 +60,6 @@ enum imx8qxp_pc_pix_data_format {
 
 struct imx8qxp_pc_channel {
 	struct drm_bridge bridge;
-	struct drm_bridge *next_bridge;
 	struct imx8qxp_pc *pc;
 	unsigned int stream_id;
 };
@@ -120,7 +119,7 @@ static int imx8qxp_pc_bridge_attach(struct drm_bridge *bridge,
 	}
 
 	return drm_bridge_attach(encoder,
-				 ch->next_bridge, bridge,
+				 ch->bridge.next_bridge, bridge,
 				 DRM_BRIDGE_ATTACH_NO_CONNECTOR);
 }
 
@@ -326,8 +325,8 @@ static int imx8qxp_pc_bridge_probe(struct platform_device *pdev)
 			goto free_child;
 		}
 
-		ch->next_bridge = of_drm_find_bridge(remote);
-		if (!ch->next_bridge) {
+		ch->bridge.next_bridge = of_drm_find_and_get_bridge(remote);
+		if (!ch->bridge.next_bridge) {
 			of_node_put(remote);
 			ret = -EPROBE_DEFER;
 			DRM_DEV_DEBUG_DRIVER(dev,
@@ -349,7 +348,7 @@ static int imx8qxp_pc_bridge_probe(struct platform_device *pdev)
 free_child:
 	of_node_put(child);
 
-	if (i == 1 && pc->ch[0]->next_bridge)
+	if (i == 1 && pc->ch[0]->bridge.next_bridge)
 		drm_bridge_remove(&pc->ch[0]->bridge);
 
 	pm_runtime_disable(dev);

-- 
2.52.0