[PATCH] drm/mediatek: Keep the mutex node reference across deferred binds

[Yige Jiang]

mtk_drm_probe() acquires private->mutex_node and releases that reference
on probe failure or in mtk_drm_remove(). The component bind callback does
not acquire another reference, so it must not put the node when the mutex
platform device is not available.

If this bind failure propagates through component_master_add_with_match(),
the probe error path puts the same reference again. A bind attempted after
probe has returned can also leave the stored node without its reference
for a later bind or remove.

Remove the bind-time put and leave the node reference with its probe/remove
owner.

Fixes: 119f5173628a ("drm/mediatek: Add DRM Driver for Mediatek SoC MT8173.")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Yige Jiang <yigejiang86@xxxxxxxxx>
---
AI assistance was used for analysis and patch preparation.

Based on next-20261104 (8b7179210b22).
Compile-tested: arm64, GCC 14.2.0, W=1, drivers/gpu/drm/mediatek/mtk_drm_drv.o;
baseline and patched objects built with no warnings.
Static source review; no hardware, boot, or KASAN test was performed.

 drivers/gpu/drm/mediatek/mtk_drm_drv.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.c b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
index dc8e3e917dd771b950167d04c1ab87c14dbabf72..64c912ba95899128bfb1a41765579d9d70979a27 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_drv.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
@@ -630,7 +630,6 @@ static int mtk_drm_bind(struct device *dev)
 	if (!pdev) {
 		dev_err(dev, "Waiting for disp-mutex device %pOF\n",
 			private->mutex_node);
-		of_node_put(private->mutex_node);
 		return -EPROBE_DEFER;
 	}

base-commit: 8b7179210b22f8e48a82c5ceacb9d56a9c4cfec4