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

From: Allen-KH Cheng
Date: Wed Sep 14 2022 - 10:02:09 EST


From: Xinlei Lee <xinlei.lee@xxxxxxxxxxxx>

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@xxxxxxxxxxxx>
Co-developed-by: Allen-KH Cheng <allen-kh.cheng@xxxxxxxxxxxx>
Signed-off-by: Allen-KH Cheng <allen-kh.cheng@xxxxxxxxxxxx>
---
Change in v1:
* Rebase to kernel/git/chunkuang.hu/linux.git, mediatek-drm-fixes
[Allen-KH Cheng <allen-kh.cheng@xxxxxxxxxxxx>]
---
---
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