# \[PATCH 15/21\] backlight: Probe backlight devices on demand

- From: Tomeu Vizoso \<hidden\>
- Date: 2015-05-25 15:01:12 
- List: linux-fbdev
- Page: https://ratatoskr.run/linux-fbdev/2015/05/4501601
- Thread: https://ratatoskr.run/linux-arm-kernel/2015/05/4501586/t.md

```text
When looking up a backlight device through its DT node, ensure that the
corresponding device has been registered.

Signed-off-by: Tomeu Vizoso <redacted>
---
 drivers/video/backlight/backlight.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c
index bddc8b1..fe7833b 100644
--- a/drivers/video/backlight/backlight.c
+++ b/drivers/video/backlight/backlight.c
@@ -12,6 +12,7 @@
 #include <linux/device.h>
 #include <linux/backlight.h>
 #include <linux/notifier.h>
+#include <linux/of_platform.h>
 #include <linux/ctype.h>
 #include <linux/err.h>
 #include <linux/fb.h>
@@ -559,6 +560,8 @@ struct backlight_device *of_find_backlight_by_node(struct device_node *node)
 {
 	struct device *dev;
 
+	of_platform_device_ensure(node);
+
 	dev = class_find_device(backlight_class, NULL, node, of_parent_match);
 
 	return dev ? to_backlight_device(dev) : NULL;
-- 
2.4.1

```