disp: msm: sde: add line insertion support for sspp

Add line insertion support for sspp, this is used to support
display with external splitter. Line insertion logic checks
the difference between screen logical height and physical
height. If any difference is observed adds dummy and active
lines on screen.

Change-Id: Ieec322273df000a53fb39e05174c2d67c3c2da81
Signed-off-by: Rajesh kv <quic_kvrajesh@quicinc.com>

msm/sde/sde_encoder.c

@@ -1069,6 +1069,32 @@ static int _sde_encoder_atomic_check_reserve(struct drm_encoder *drm_enc,
 	return ret;
 }
 
+bool sde_encoder_is_line_insertion_supported(struct drm_encoder *drm_enc)
+{
+	struct sde_connector *sde_conn = NULL;
+	struct sde_kms *sde_kms = NULL;
+	struct drm_connector *conn = NULL;
+
+	if (!drm_enc) {
+		SDE_ERROR("invalid drm encoder\n");
+		return false;
+	}
+
+	sde_kms = sde_encoder_get_kms(drm_enc);
+	if (!sde_kms)
+		return false;
+
+	conn = sde_encoder_get_connector(sde_kms->dev, drm_enc);
+	if (!conn || !conn->state)
+		return false;
+
+	sde_conn = to_sde_connector(conn);
+	if (!sde_conn)
+		return false;
+
+	return sde_connector_is_line_insertion_supported(sde_conn);
+}
+
 static void _sde_encoder_get_qsync_fps_callback(struct drm_encoder *drm_enc,
 			u32 *qsync_fps, struct drm_connector_state *conn_state)
 {