[PATCH 3/4] drm/fsl-dcu: update all registers on flush

[Stefan Agner]

Use the UPDATE_MODE READREG bit to initiate a register transfer
on flush. This makes sure that we flush all registers only once
for all planes.

Signed-off-by: Stefan Agner <stefan at agner.ch>
---
 drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_crtc.c  | 3 +++
 drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_plane.c | 5 -----
 2 files changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_crtc.c 
b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_crtc.c
index d30b61e..62eb284 100644
--- a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_crtc.c
+++ b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_crtc.c
@@ -27,6 +27,9 @@ static void fsl_dcu_drm_crtc_atomic_flush(struct drm_crtc 
*crtc,
 {
        struct drm_pending_vblank_event *event = crtc->state->event;

+       regmap_write(fsl_dev->regmap,
+                    DCU_UPDATE_MODE, DCU_UPDATE_MODE_READREG);
+
        if (event) {
                crtc->state->event = NULL;

diff --git a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_plane.c 
b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_plane.c
index a6af3d9..d7412ff 100644
--- a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_plane.c
+++ b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_plane.c
@@ -160,11 +160,6 @@ static void fsl_dcu_drm_plane_atomic_update(struct 
drm_plane *plane,
                             DCU_LAYER_POST_SKIP(0) |
                             DCU_LAYER_PRE_SKIP(0));
        }
-       regmap_update_bits(fsl_dev->regmap, DCU_DCU_MODE,
-                          DCU_MODE_DCU_MODE_MASK,
-                          DCU_MODE_DCU_MODE(DCU_MODE_NORMAL));
-       regmap_write(fsl_dev->regmap,
-                    DCU_UPDATE_MODE, DCU_UPDATE_MODE_READREG);

        return;
 }
-- 
2.9.3