2 files changed, 36 insertions, 1 deletions

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
index 7efd12312354..0dc09d92d92d 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
@@ -245,6 +245,39 @@ static struct platform_driver *rockchip_sub_drivers[MAX_ROCKCHIP_SUB_DRIVERS];
 static int num_rockchip_sub_drivers;
 
 /*
+ * Get the endpoint id of the remote endpoint of the given encoder. This
+ * information is used by the VOP2 driver to identify the encoder.
+ *
+ * @rkencoder: The encoder to get the remote endpoint id from
+ * @np: The encoder device node
+ * @port: The number of the port leading to the VOP2
+ * @reg: The endpoint number leading to the VOP2
+ */
+int rockchip_drm_encoder_set_crtc_endpoint_id(struct rockchip_encoder *rkencoder,
+					      struct device_node *np, int port, int reg)
+{
+	struct of_endpoint ep;
+	struct device_node *en, *ren;
+	int ret;
+
+	en = of_graph_get_endpoint_by_regs(np, port, reg);
+	if (!en)
+		return -ENOENT;
+
+	ren = of_graph_get_remote_endpoint(en);
+	if (!ren)
+		return -ENOENT;
+
+	ret = of_graph_parse_endpoint(ren, &ep);
+	if (ret)
+		return ret;
+
+	rkencoder->crtc_endpoint_id = ep.id;
+
+	return 0;
+}
+
+/*
  * Check if a vop endpoint is leading to a rockchip subdriver or bridge.
  * Should be called from the component bind stage of the drivers
  * to ensure that all subdrivers are probed.
diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_drv.h b/drivers/gpu/drm/rockchip/rockchip_drm_drv.h
index 048ab277de65..a27ab928e1d2 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_drv.h
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_drv.h
@@ -50,6 +50,7 @@ struct rockchip_drm_private {
 };
 
 struct rockchip_encoder {
+	int crtc_endpoint_id;
 	struct drm_encoder encoder;
 };
 
@@ -60,7 +61,8 @@ void rockchip_drm_dma_detach_device(struct drm_device *drm_dev,
 void rockchip_drm_dma_init_device(struct drm_device *drm_dev,
 				  struct device *dev);
 int rockchip_drm_wait_vact_end(struct drm_crtc *crtc, unsigned int mstimeout);
-
+int rockchip_drm_encoder_set_crtc_endpoint_id(struct rockchip_encoder *rencoder,
+					      struct device_node *np, int port, int reg);
 int rockchip_drm_endpoint_is_subdriver(struct device_node *ep);
 extern struct platform_driver cdn_dp_driver;
 extern struct platform_driver dw_hdmi_rockchip_pltfm_driver;