drm/rockchip: add function to check if endpoint is a subdriver

To be able to have both internal subdrivers and external bridge
drivers as output endpoints of vops, add a function to be able
to distinguish these.

changes in v8:
- improved function documentation
- better error handling
- put calls for node and pdev references
changes in v6:
- added function to check subdriver vs. bridge

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Sandy Huang <hjc@rock-chips.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180830211207.10480-2-heiko@sntech.de

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_drv.h b/drivers/gpu/drm/rockchip/rockchip_drm_drv.h
index d67ad0a3cf36..21a023a97bb8 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_drv.h
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_drv.h
@@ -64,6 +64,7 @@ void rockchip_drm_dma_detach_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_endpoint_is_subdriver(struct device_node *ep);
 extern struct platform_driver cdn_dp_driver;
 extern struct platform_driver dw_hdmi_rockchip_pltfm_driver;
 extern struct platform_driver dw_mipi_dsi_driver;