[PATCH v2, 1/2] drm/mediatek: Fix gamma correction issue

[Yongqiang Niu <yongqiang.niu@mediatek.com>]

if there is no gamma function in the crtc
display path, don't add gamma property
for crtc

Signed-off-by: Yongqiang Niu <yongqiang.niu@mediatek.com>
---
 drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
index ca4fc47..9a8e1d4 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
@@ -734,6 +734,7 @@ int mtk_drm_crtc_create(struct drm_device *drm_dev,
 	int pipe = priv->num_pipes;
 	int ret;
 	int i;
+	uint gamma_lut_size = 0;
 
 	if (!path)
 		return 0;
@@ -785,6 +786,9 @@ int mtk_drm_crtc_create(struct drm_device *drm_dev,
 		}
 
 		mtk_crtc->ddp_comp[i] = comp;
+
+		if (comp->funcs->gamma_set)
+			gamma_lut_size = MTK_LUT_SIZE;
 	}
 
 	for (i = 0; i < mtk_crtc->ddp_comp_nr; i++)
@@ -805,8 +809,10 @@ int mtk_drm_crtc_create(struct drm_device *drm_dev,
 				NULL, pipe);
 	if (ret < 0)
 		return ret;
-	drm_mode_crtc_set_gamma_size(&mtk_crtc->base, MTK_LUT_SIZE);
-	drm_crtc_enable_color_mgmt(&mtk_crtc->base, 0, false, MTK_LUT_SIZE);
+
+	if (gamma_lut_size)
+		drm_mode_crtc_set_gamma_size(&mtk_crtc->base, gamma_lut_size);
+	drm_crtc_enable_color_mgmt(&mtk_crtc->base, 0, false, gamma_lut_size);
 	priv->num_pipes++;
 	mutex_init(&mtk_crtc->hw_lock);
 
-- 
1.8.1.1.dirty