drm: meson: use vblank hooks in struct drm_crtc_funcs

The vblank hooks in struct drm_driver are deprecated and only meant for
legacy drivers.  For modern drivers with DRIVER_MODESET flag, the hooks
in struct drm_crtc_funcs should be used instead.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1486458995-31018-15-git-send-email-shawnguo@kernel.org
diff --git a/drivers/gpu/drm/meson/meson_crtc.c b/drivers/gpu/drm/meson/meson_crtc.c
index 749770e..0fe49ec 100644
--- a/drivers/gpu/drm/meson/meson_crtc.c
+++ b/drivers/gpu/drm/meson/meson_crtc.c
@@ -33,6 +33,7 @@
 
 #include "meson_crtc.h"
 #include "meson_plane.h"
+#include "meson_venc.h"
 #include "meson_vpp.h"
 #include "meson_viu.h"
 #include "meson_registers.h"
@@ -48,6 +49,24 @@ struct meson_crtc {
 
 /* CRTC */
 
+static int meson_crtc_enable_vblank(struct drm_crtc *crtc)
+{
+	struct meson_crtc *meson_crtc = to_meson_crtc(crtc);
+	struct meson_drm *priv = meson_crtc->priv;
+
+	meson_venc_enable_vsync(priv);
+
+	return 0;
+}
+
+static void meson_crtc_disable_vblank(struct drm_crtc *crtc)
+{
+	struct meson_crtc *meson_crtc = to_meson_crtc(crtc);
+	struct meson_drm *priv = meson_crtc->priv;
+
+	meson_venc_disable_vsync(priv);
+}
+
 static const struct drm_crtc_funcs meson_crtc_funcs = {
 	.atomic_destroy_state	= drm_atomic_helper_crtc_destroy_state,
 	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
@@ -55,6 +74,9 @@ static const struct drm_crtc_funcs meson_crtc_funcs = {
 	.page_flip		= drm_atomic_helper_page_flip,
 	.reset			= drm_atomic_helper_crtc_reset,
 	.set_config             = drm_atomic_helper_set_config,
+	.enable_vblank		= meson_crtc_enable_vblank,
+	.disable_vblank		= meson_crtc_disable_vblank,
+
 };
 
 static void meson_crtc_enable(struct drm_crtc *crtc)