[RFC PATCH v2 15/20] drm/drm_ioctl: guard DRM_CLIENT_CAP_CRTC_COLOR_PIPELINE

If the driver doesn't support post-blend colorop, refuse attempts from
usersapce to set it. Same approach is taken for pre-blend colorop.

Signed-off-by: Melissa Wen <[email protected]>
---
 drivers/gpu/drm/drm_ioctl.c | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c
index ae374733e154..82d4f1bfc557 100644
--- a/drivers/gpu/drm/drm_ioctl.c
+++ b/drivers/gpu/drm/drm_ioctl.c
@@ -380,13 +380,26 @@ drm_setclientcap(struct drm_device *dev, void *data, struct drm_file *file_priv)
 			return -EINVAL;
 		file_priv->plane_color_pipeline = req->value;
 		break;
-	case DRM_CLIENT_CAP_CRTC_COLOR_PIPELINE:
+	case DRM_CLIENT_CAP_CRTC_COLOR_PIPELINE: {
+		struct drm_crtc *crtc;
+		bool has_crtc_with_color_pipeline = false;
+
 		if (!file_priv->atomic)
 			return -EINVAL;
 		if (req->value > 1)
 			return -EINVAL;
+		drm_for_each_crtc(crtc, dev) {
+			if (crtc->color_pipeline_property) {
+				has_crtc_with_color_pipeline = true;
+				break;
+			}
+		}
+		if (req->value == 1 && !has_crtc_with_color_pipeline)
+			return -EOPNOTSUPP;
+
 		file_priv->crtc_color_pipeline = req->value;
 		break;
+	}
 	default:
 		return -EINVAL;
 	}
-- 
2.53.0