From: Jack Leigh <jack.leigh@collabora.com>
Date: Tue, 30 Sep 2014 14:36:00 +0100
Subject: Export acpi_video_verify_backlight_support as in 3.16

---
 drivers/acpi/video.c | 3 ++-
 include/acpi/video.h | 2 ++
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index e858463..8125e98 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -241,13 +241,14 @@ static bool acpi_video_use_native_backlight(void)
 		return use_native_backlight_dmi;
 }
 
-static bool acpi_video_verify_backlight_support(void)
+bool acpi_video_verify_backlight_support(void)
 {
 	if (acpi_osi_is_win8() && acpi_video_use_native_backlight() &&
 	    backlight_device_registered(BACKLIGHT_RAW))
 		return false;
 	return acpi_video_backlight_support();
 }
+EXPORT_SYMBOL_GPL(acpi_video_verify_backlight_support);
 
 /* backlight device sysfs support */
 static int acpi_video_get_brightness(struct backlight_device *bd)
diff --git a/include/acpi/video.h b/include/acpi/video.h
index 61109f2..93af207 100644
--- a/include/acpi/video.h
+++ b/include/acpi/video.h
@@ -21,6 +21,7 @@ extern int acpi_video_register(void);
 extern void acpi_video_unregister(void);
 extern int acpi_video_get_edid(struct acpi_device *device, int type,
 			       int device_id, void **edid);
+extern bool acpi_video_verify_backlight_support(void);
 #else
 static inline int acpi_video_register(void) { return 0; }
 static inline void acpi_video_unregister(void) { return; }
@@ -29,6 +30,7 @@ static inline int acpi_video_get_edid(struct acpi_device *device, int type,
 {
 	return -ENODEV;
 }
+static inline bool acpi_video_verify_backlight_support(void) { return false; }
 #endif
 
 #endif
