drm: hdlcd: 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>
Acked-by: Liviu Dudau <liviu.dudau@arm.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1486458995-31018-5-git-send-email-shawnguo@kernel.org
diff --git a/drivers/gpu/drm/arm/hdlcd_crtc.c b/drivers/gpu/drm/arm/hdlcd_crtc.c
index 20ebfb4..798a3cc 100644
--- a/drivers/gpu/drm/arm/hdlcd_crtc.c
+++ b/drivers/gpu/drm/arm/hdlcd_crtc.c
@@ -42,6 +42,24 @@ static void hdlcd_crtc_cleanup(struct drm_crtc *crtc)
 	drm_crtc_cleanup(crtc);
 }
 
+static int hdlcd_crtc_enable_vblank(struct drm_crtc *crtc)
+{
+	struct hdlcd_drm_private *hdlcd = crtc_to_hdlcd_priv(crtc);
+	unsigned int mask = hdlcd_read(hdlcd, HDLCD_REG_INT_MASK);
+
+	hdlcd_write(hdlcd, HDLCD_REG_INT_MASK, mask | HDLCD_INTERRUPT_VSYNC);
+
+	return 0;
+}
+
+static void hdlcd_crtc_disable_vblank(struct drm_crtc *crtc)
+{
+	struct hdlcd_drm_private *hdlcd = crtc_to_hdlcd_priv(crtc);
+	unsigned int mask = hdlcd_read(hdlcd, HDLCD_REG_INT_MASK);
+
+	hdlcd_write(hdlcd, HDLCD_REG_INT_MASK, mask & ~HDLCD_INTERRUPT_VSYNC);
+}
+
 static const struct drm_crtc_funcs hdlcd_crtc_funcs = {
 	.destroy = hdlcd_crtc_cleanup,
 	.set_config = drm_atomic_helper_set_config,
@@ -49,6 +67,8 @@ static const struct drm_crtc_funcs hdlcd_crtc_funcs = {
 	.reset = drm_atomic_helper_crtc_reset,
 	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
 	.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
+	.enable_vblank = hdlcd_crtc_enable_vblank,
+	.disable_vblank = hdlcd_crtc_disable_vblank,
 };
 
 static struct simplefb_format supported_formats[] = SIMPLEFB_FORMATS;