linux-kernel - [PATCH v3 17/22] drm/bridge: imx8qxp-pxl2dpi: get/put the companion bridge

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Message-Id: <20251216-drm-bridge-alloc-getput-drm_of_find_bridge-v3-17-b5165fab8058@bootlin.com>
Date: Tue, 16 Dec 2025 18:58:50 +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 17/22] drm/bridge: imx8qxp-pxl2dpi: get/put the
 companion 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 the destroy hook to put the reference on deallocation.

Signed-off-by: Luca Ceresoli <luca.ceresoli@...tlin.com>
---
 drivers/gpu/drm/bridge/imx/imx8qxp-pxl2dpi.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/bridge/imx/imx8qxp-pxl2dpi.c b/drivers/gpu/drm/bridge/imx/imx8qxp-pxl2dpi.c
index 556aec3b3734..2c40ca86e319 100644
--- a/drivers/gpu/drm/bridge/imx/imx8qxp-pxl2dpi.c
+++ b/drivers/gpu/drm/bridge/imx/imx8qxp-pxl2dpi.c
@@ -63,6 +63,13 @@ static int imx8qxp_pxl2dpi_bridge_attach(struct drm_bridge *bridge,
 				 DRM_BRIDGE_ATTACH_NO_CONNECTOR);
 }
 
+static void imx8qxp_pxl2dpi_bridge_destroy(struct drm_bridge *bridge)
+{
+	struct imx8qxp_pxl2dpi *p2d = bridge->driver_private;
+
+	drm_bridge_put(p2d->companion);
+}
+
 static int
 imx8qxp_pxl2dpi_bridge_atomic_check(struct drm_bridge *bridge,
 				    struct drm_bridge_state *bridge_state,
@@ -205,6 +212,7 @@ static const struct drm_bridge_funcs imx8qxp_pxl2dpi_bridge_funcs = {
 	.atomic_destroy_state	= drm_atomic_helper_bridge_destroy_state,
 	.atomic_reset		= drm_atomic_helper_bridge_reset,
 	.attach			= imx8qxp_pxl2dpi_bridge_attach,
+	.destroy		= imx8qxp_pxl2dpi_bridge_destroy,
 	.atomic_check		= imx8qxp_pxl2dpi_bridge_atomic_check,
 	.mode_set		= imx8qxp_pxl2dpi_bridge_mode_set,
 	.atomic_disable		= imx8qxp_pxl2dpi_bridge_atomic_disable,
@@ -333,7 +341,7 @@ static int imx8qxp_pxl2dpi_parse_dt_companion(struct imx8qxp_pxl2dpi *p2d)
 		goto out;
 	}
 
-	p2d->companion = of_drm_find_bridge(companion);
+	p2d->companion = of_drm_find_and_get_bridge(companion);
 	if (!p2d->companion) {
 		ret = -EPROBE_DEFER;
 		DRM_DEV_DEBUG_DRIVER(p2d->dev,

-- 
2.52.0