dm: panel: Add a panel uclass

LCD panels can usefully be modelled as their own uclass. They can be probed
(which powers them up ready for use). If they have a backlight, this can be
enabled.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/video/panel-uclass.c b/drivers/video/panel-uclass.c
new file mode 100644
index 0000000..3f4c41b
--- /dev/null
+++ b/drivers/video/panel-uclass.c
@@ -0,0 +1,25 @@
+/*
+ * Copyright (c) 2016 Google, Inc
+ * Written by Simon Glass <sjg@chromium.org>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <panel.h>
+
+int panel_enable_backlight(struct udevice *dev)
+{
+	struct panel_ops *ops = panel_get_ops(dev);
+
+	if (!ops->enable_backlight)
+		return -ENOSYS;
+
+	return ops->enable_backlight(dev);
+}
+
+UCLASS_DRIVER(panel) = {
+	.id		= UCLASS_PANEL,
+	.name		= "panel",
+};