video: Add a function to control cache flushing

Allow the cache-flushing function of a video device to be controlled.
Signed-off-by: NSimon Glass <sjg@chromium.org>

drivers/video/video-uclass.c

@@ -42,6 +42,13 @@
  */
 DECLARE_GLOBAL_DATA_PTR;
 
+void video_set_flush_dcache(struct udevice *dev, bool flush)
+{
+	struct video_priv *priv = dev_get_uclass_priv(dev);
+
+	priv->flush_dcache = flush;
+}
+
 static ulong alloc_fb(struct udevice *dev, ulong *addrp)
 {
 	struct video_uc_platdata *plat = dev_get_uclass_platdata(dev);

include/video.h

@@ -158,6 +158,14 @@ int video_get_xsize(struct udevice *dev);
  */
 int video_get_ysize(struct udevice *dev);
 
+/**
+ * Set whether we need to flush the dcache when changing the image. This
+ * defaults to off.
+ *
+ * @param flush		non-zero to flush cache after update, 0 to skip
+ */
+void video_set_flush_dcache(struct udevice *dev, bool flush);
+
 #endif /* CONFIG_DM_VIDEO */
 
 #ifndef CONFIG_DM_VIDEO