[PATCH v2] drm: mediatek: Fix display vblank timeout when disable dsi

[Allen-KH Cheng]

From: Xinlei Lee <xinlei.lee at mediatek.com>

Dsi is turned off at bridge.disable, causing crtc to wait for vblank
timeout. It is necessary to add count protection to turn off dsi and
turn off at post_disable.

Fixes: cde7e2e35c28 ("drm/mediatek: Separate poweron/poweroff from enable/disable and define new funcs")
Signed-off-by: Xinlei Lee <xinlei.lee at mediatek.com>
Co-developed-by: Allen-KH Cheng <allen-kh.cheng at mediatek.com>
Signed-off-by: Allen-KH Cheng <allen-kh.cheng at mediatek.com>
---
Change in v1:
  * Rebase to kernel/git/chunkuang.hu/linux.git, mediatek-drm-fixes
    [Allen-KH Cheng <allen-kh.cheng at mediatek.com>]
---
---
 drivers/gpu/drm/mediatek/mtk_dsi.c | 15 ++++++---------
 1 file changed, 6 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c b/drivers/gpu/drm/mediatek/mtk_dsi.c
index 5b624e0f5b0a..e30f4244c001 100644
--- a/drivers/gpu/drm/mediatek/mtk_dsi.c
+++ b/drivers/gpu/drm/mediatek/mtk_dsi.c
@@ -768,14 +768,6 @@ static void mtk_dsi_bridge_mode_set(struct drm_bridge *bridge,
 	drm_display_mode_to_videomode(adjusted, &dsi->vm);
 }
 
-static void mtk_dsi_bridge_atomic_disable(struct drm_bridge *bridge,
-					  struct drm_bridge_state *old_bridge_state)
-{
-	struct mtk_dsi *dsi = bridge_to_dsi(bridge);
-
-	mtk_output_dsi_disable(dsi);
-}
-
 static void mtk_dsi_bridge_atomic_enable(struct drm_bridge *bridge,
 					 struct drm_bridge_state *old_bridge_state)
 {
@@ -803,13 +795,15 @@ static void mtk_dsi_bridge_atomic_post_disable(struct drm_bridge *bridge,
 {
 	struct mtk_dsi *dsi = bridge_to_dsi(bridge);
 
+	if (dsi->refcount == 1)
+		mtk_output_dsi_disable(dsi);
+
 	mtk_dsi_poweroff(dsi);
 }
 
 static const struct drm_bridge_funcs mtk_dsi_bridge_funcs = {
 	.attach = mtk_dsi_bridge_attach,
 	.atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
-	.atomic_disable = mtk_dsi_bridge_atomic_disable,
 	.atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
 	.atomic_enable = mtk_dsi_bridge_atomic_enable,
 	.atomic_pre_enable = mtk_dsi_bridge_atomic_pre_enable,
@@ -829,6 +823,9 @@ void mtk_dsi_ddp_stop(struct device *dev)
 {
 	struct mtk_dsi *dsi = dev_get_drvdata(dev);
 
+	if (dsi->refcount == 1)
+		mtk_output_dsi_disable(dsi);
+
 	mtk_dsi_poweroff(dsi);
 }
 
-- 
2.18.0