linux-kernel - [PATCH v3 16/22] drm/bridge: imx8qxp-pxl2dpi: get/put the next bridge

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Message-Id: <20251216-drm-bridge-alloc-getput-drm_of_find_bridge-v3-16-b5165fab8058@bootlin.com>
Date: Tue, 16 Dec 2025 18:58:49 +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 16/22] drm/bridge: imx8qxp-pxl2dpi: 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-pxl2dpi.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/bridge/imx/imx8qxp-pxl2dpi.c b/drivers/gpu/drm/bridge/imx/imx8qxp-pxl2dpi.c
index 2e66b003386e..556aec3b3734 100644
--- a/drivers/gpu/drm/bridge/imx/imx8qxp-pxl2dpi.c
+++ b/drivers/gpu/drm/bridge/imx/imx8qxp-pxl2dpi.c
@@ -35,7 +35,6 @@
 struct imx8qxp_pxl2dpi {
 	struct regmap *regmap;
 	struct drm_bridge bridge;
-	struct drm_bridge *next_bridge;
 	struct drm_bridge *companion;
 	struct device *dev;
 	struct imx_sc_ipc *ipc_handle;
@@ -60,7 +59,7 @@ static int imx8qxp_pxl2dpi_bridge_attach(struct drm_bridge *bridge,
 	}
 
 	return drm_bridge_attach(encoder,
-				 p2d->next_bridge, bridge,
+				 p2d->bridge.next_bridge, bridge,
 				 DRM_BRIDGE_ATTACH_NO_CONNECTOR);
 }
 
@@ -271,8 +270,8 @@ static int imx8qxp_pxl2dpi_find_next_bridge(struct imx8qxp_pxl2dpi *p2d)
 		return -ENODEV;
 	}
 
-	p2d->next_bridge = of_drm_find_bridge(remote);
-	if (!p2d->next_bridge)
+	p2d->bridge.next_bridge = of_drm_find_and_get_bridge(remote);
+	if (!p2d->bridge.next_bridge)
 		return -EPROBE_DEFER;
 
 	return 0;
@@ -351,8 +350,8 @@ static int imx8qxp_pxl2dpi_parse_dt_companion(struct imx8qxp_pxl2dpi *p2d)
 	 * the next bridges are connected to.  If they are marked as expecting
 	 * even pixels and odd pixels than we need to use the companion PXL2DPI.
 	 */
-	port1 = of_graph_get_port_by_id(p2d->next_bridge->of_node, 1);
-	port2 = of_graph_get_port_by_id(companion_p2d->next_bridge->of_node, 1);
+	port1 = of_graph_get_port_by_id(p2d->bridge.next_bridge->of_node, 1);
+	port2 = of_graph_get_port_by_id(companion_p2d->bridge.next_bridge->of_node, 1);
 	dual_link = drm_of_lvds_get_dual_link_pixel_order(port1, port2);
 	of_node_put(port1);
 	of_node_put(port2);

-- 
2.52.0