[PATCH 5.8 067/118] drm/mediatek: Use CPU when fail to get cmdq event

[Greg Kroah-Hartman]

From: Chun-Kuang Hu <chunkuang.hu@xxxxxxxxxx>

[ Upstream commit f85acdad07fe36b91f2244263a890bf372528326 ]

Even though cmdq client is created successfully, without the cmdq event,
cmdq could not work correctly, so use CPU when fail to get cmdq event.

Fixes: 60fa8c13ab1a ("drm/mediatek: Move gce event property to mutex device node")
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 20 +++++++++++++-------
 1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
index 7cd8f415fd029..d8b43500f12d1 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
@@ -834,13 +834,19 @@ int mtk_drm_crtc_create(struct drm_device *drm_dev,
 			drm_crtc_index(&mtk_crtc->base));
 		mtk_crtc->cmdq_client = NULL;
 	}
-	ret = of_property_read_u32_index(priv->mutex_node,
-					 "mediatek,gce-events",
-					 drm_crtc_index(&mtk_crtc->base),
-					 &mtk_crtc->cmdq_event);
-	if (ret)
-		dev_dbg(dev, "mtk_crtc %d failed to get mediatek,gce-events property\n",
-			drm_crtc_index(&mtk_crtc->base));
+
+	if (mtk_crtc->cmdq_client) {
+		ret = of_property_read_u32_index(priv->mutex_node,
+						 "mediatek,gce-events",
+						 drm_crtc_index(&mtk_crtc->base),
+						 &mtk_crtc->cmdq_event);
+		if (ret) {
+			dev_dbg(dev, "mtk_crtc %d failed to get mediatek,gce-events property\n",
+				drm_crtc_index(&mtk_crtc->base));
+			cmdq_mbox_destroy(mtk_crtc->cmdq_client);
+			mtk_crtc->cmdq_client = NULL;
+		}
+	}
 #endif
 	return 0;
 }
-- 
2.25.1