dm: backlight: Add a backlight uclass

LCD panels normally have a backlight which can be controlled to illuminate
the LCD contents. Add a uclass to support this. Initially it only has a
method to enable the backlight.

Signed-off-by: Simon Glass <sjg@chromium.org>

2 files changed, 26 insertions, 0 deletions

diff --git a/drivers/video/Makefile b/drivers/video/Makefile
index ee046296e6..fa907210cf 100644
--- a/drivers/video/Makefile
+++ b/drivers/video/Makefile
@@ -7,6 +7,7 @@
 
 ifdef CONFIG_DM
 obj-$(CONFIG_DISPLAY_PORT) += dp-uclass.o
+obj-$(CONFIG_DM_VIDEO) += backlight-uclass.o
 obj-$(CONFIG_DM_VIDEO) += video-uclass.o vidconsole-uclass.o console_normal.o
 obj-$(CONFIG_DM_VIDEO) += video_bmp.o
 obj-$(CONFIG_VIDEO_ROTATION) += console_rotate.o
diff --git a/drivers/video/backlight-uclass.c b/drivers/video/backlight-uclass.c
new file mode 100644
index 0000000000..0238289d1b
--- /dev/null
+++ b/drivers/video/backlight-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 <backlight.h>
+
+int backlight_enable(struct udevice *dev)
+{
+	const struct backlight_ops *ops = backlight_get_ops(dev);
+
+	if (!ops->enable)
+		return -ENOSYS;
+
+	return ops->enable(dev);
+}
+
+UCLASS_DRIVER(backlight) = {
+	.id		= UCLASS_PANEL_BACKLIGHT,
+	.name		= "backlight",
+};