[PATCH 1/3] video: Introduce video_sync call

[Michal Simek]

Some drivers like LCD connected via SPI requires explicit sync function
which copy framebuffer content over SPI to controller to display.
This hook doesn't exist yet that's why introduce it via video operations.

Signed-off-by: Michal Simek <michal.simek at xilinx.com>
---

Simon: Please review this. I didn't find existing way how this can be done
that's why I am introducing this hook. Also maybe name can be named a
little bit differently. That's why waiting for better suggestion.
---
 drivers/video/video-uclass.c |  5 +++++
 include/video.h              | 13 +++++++++++++
 2 files changed, 18 insertions(+)

diff --git a/drivers/video/video-uclass.c b/drivers/video/video-uclass.c
index 650891e49dd0..ba52a6c7125b 100644
--- a/drivers/video/video-uclass.c
+++ b/drivers/video/video-uclass.c
@@ -174,6 +174,11 @@ void video_set_default_colors(struct udevice *dev, bool invert)
 /* Flush video activity to the caches */
 void video_sync(struct udevice *vid, bool force)
 {
+	struct video_ops *ops = video_get_ops(vid);
+
+	if (ops && ops->video_sync)
+		(void)ops->video_sync(vid);
+
 	/*
 	 * flush_dcache_range() is declared in common.h but it seems that some
 	 * architectures do not actually implement it. Is there a way to find
diff --git a/include/video.h b/include/video.h
index 9d09d2409af6..acac3f6b3c8d 100644
--- a/include/video.h
+++ b/include/video.h
@@ -115,7 +115,20 @@ struct video_priv {
 };
 
 /* Placeholder - there are no video operations at present */
+/**
+ * struct video_ops - structure for keeping video operations
+ */
 struct video_ops {
+	/**
+	 * video_sync - Synchronize FB with device
+	 *
+	 * Some device like SPI based LCD displays needs synchronization when
+	 * data in an FB is available. For these devices implement video_sync
+	 * hook to call a sync function
+	 *
+	 * @vid:	Video device udevice structure
+	 */
+	int (*video_sync)(struct udevice *vid);
 };
 
 #define video_get_ops(dev)        ((struct video_ops *)(dev)->driver->ops)
-- 
2.29.2