[PATCH v8 21/23] drm/mediatek: Fix underrun in VDO1 when switches off the layer

Hsiao Chien Sung
2023-10-16T10:42:07Z

Do not reset Merge while using CMDQ because reset API doesn't
wait for frame done event as CMDQ does and could lead to
underrun when the layer is switching off.

Fixes: aaf94f7c3ae6 ("drm/mediatek: Add display merge async reset control")

Signed-off-by: Hsiao Chien Sung <shawn.sung@mediatek.com>
---
drivers/gpu/drm/mediatek/mtk_disp_merge.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_disp_merge.c b/drivers/gpu/drm/mediatek/mtk_disp_merge.c
index fd14a59bc951..c19fb1836034 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_merge.c
+++ b/drivers/gpu/drm/mediatek/mtk_disp_merge.c
@@ -104,7 +104,7 @@ void mtk_merge_stop_cmdq(struct device *dev, struct cmdq_pkt *cmdq_pkt)
mtk_ddp_write(cmdq_pkt, 0, &priv->cmdq_reg, priv->regs,
DISP_REG_MERGE_CTRL);

- if (priv->async_clk)
+ if (!cmdq_pkt && priv->async_clk)
reset_control_reset(priv->reset_ctl);
}

--
2.18.0